xref: /linux/net/ipv6/addrconf.c (revision e6a901a00822659181c93c86d8bbc2a17779fddc)
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_min_advance	= REGEN_MIN_ADVANCE,
199 	.regen_max_retry	= REGEN_MAX_RETRY,
200 	.max_desync_factor	= MAX_DESYNC_FACTOR,
201 	.max_addresses		= IPV6_MAX_ADDRESSES,
202 	.accept_ra_defrtr	= 1,
203 	.ra_defrtr_metric	= IP6_RT_PRIO_USER,
204 	.accept_ra_from_local	= 0,
205 	.accept_ra_min_hop_limit= 1,
206 	.accept_ra_min_lft	= 0,
207 	.accept_ra_pinfo	= 1,
208 #ifdef CONFIG_IPV6_ROUTER_PREF
209 	.accept_ra_rtr_pref	= 1,
210 	.rtr_probe_interval	= 60 * HZ,
211 #ifdef CONFIG_IPV6_ROUTE_INFO
212 	.accept_ra_rt_info_min_plen = 0,
213 	.accept_ra_rt_info_max_plen = 0,
214 #endif
215 #endif
216 	.proxy_ndp		= 0,
217 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
218 	.disable_ipv6		= 0,
219 	.accept_dad		= 0,
220 	.suppress_frag_ndisc	= 1,
221 	.accept_ra_mtu		= 1,
222 	.stable_secret		= {
223 		.initialized = false,
224 	},
225 	.use_oif_addrs_only	= 0,
226 	.ignore_routes_with_linkdown = 0,
227 	.keep_addr_on_down	= 0,
228 	.seg6_enabled		= 0,
229 #ifdef CONFIG_IPV6_SEG6_HMAC
230 	.seg6_require_hmac	= 0,
231 #endif
232 	.enhanced_dad           = 1,
233 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
234 	.disable_policy		= 0,
235 	.rpl_seg_enabled	= 0,
236 	.ioam6_enabled		= 0,
237 	.ioam6_id               = IOAM6_DEFAULT_IF_ID,
238 	.ioam6_id_wide		= IOAM6_DEFAULT_IF_ID_WIDE,
239 	.ndisc_evict_nocarrier	= 1,
240 	.ra_honor_pio_life	= 0,
241 };
242 
243 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
244 	.forwarding		= 0,
245 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
246 	.mtu6			= IPV6_MIN_MTU,
247 	.accept_ra		= 1,
248 	.accept_redirects	= 1,
249 	.autoconf		= 1,
250 	.force_mld_version	= 0,
251 	.mldv1_unsolicited_report_interval = 10 * HZ,
252 	.mldv2_unsolicited_report_interval = HZ,
253 	.dad_transmits		= 1,
254 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
255 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
256 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
257 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
258 	.use_tempaddr		= 0,
259 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
260 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
261 	.regen_min_advance	= REGEN_MIN_ADVANCE,
262 	.regen_max_retry	= REGEN_MAX_RETRY,
263 	.max_desync_factor	= MAX_DESYNC_FACTOR,
264 	.max_addresses		= IPV6_MAX_ADDRESSES,
265 	.accept_ra_defrtr	= 1,
266 	.ra_defrtr_metric	= IP6_RT_PRIO_USER,
267 	.accept_ra_from_local	= 0,
268 	.accept_ra_min_hop_limit= 1,
269 	.accept_ra_min_lft	= 0,
270 	.accept_ra_pinfo	= 1,
271 #ifdef CONFIG_IPV6_ROUTER_PREF
272 	.accept_ra_rtr_pref	= 1,
273 	.rtr_probe_interval	= 60 * HZ,
274 #ifdef CONFIG_IPV6_ROUTE_INFO
275 	.accept_ra_rt_info_min_plen = 0,
276 	.accept_ra_rt_info_max_plen = 0,
277 #endif
278 #endif
279 	.proxy_ndp		= 0,
280 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
281 	.disable_ipv6		= 0,
282 	.accept_dad		= 1,
283 	.suppress_frag_ndisc	= 1,
284 	.accept_ra_mtu		= 1,
285 	.stable_secret		= {
286 		.initialized = false,
287 	},
288 	.use_oif_addrs_only	= 0,
289 	.ignore_routes_with_linkdown = 0,
290 	.keep_addr_on_down	= 0,
291 	.seg6_enabled		= 0,
292 #ifdef CONFIG_IPV6_SEG6_HMAC
293 	.seg6_require_hmac	= 0,
294 #endif
295 	.enhanced_dad           = 1,
296 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
297 	.disable_policy		= 0,
298 	.rpl_seg_enabled	= 0,
299 	.ioam6_enabled		= 0,
300 	.ioam6_id               = IOAM6_DEFAULT_IF_ID,
301 	.ioam6_id_wide		= IOAM6_DEFAULT_IF_ID_WIDE,
302 	.ndisc_evict_nocarrier	= 1,
303 	.ra_honor_pio_life	= 0,
304 };
305 
306 /* Check if link is ready: is it up and is a valid qdisc available */
307 static inline bool addrconf_link_ready(const struct net_device *dev)
308 {
309 	return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
310 }
311 
312 static void addrconf_del_rs_timer(struct inet6_dev *idev)
313 {
314 	if (del_timer(&idev->rs_timer))
315 		__in6_dev_put(idev);
316 }
317 
318 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
319 {
320 	if (cancel_delayed_work(&ifp->dad_work))
321 		__in6_ifa_put(ifp);
322 }
323 
324 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
325 				  unsigned long when)
326 {
327 	if (!mod_timer(&idev->rs_timer, jiffies + when))
328 		in6_dev_hold(idev);
329 }
330 
331 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
332 				   unsigned long delay)
333 {
334 	in6_ifa_hold(ifp);
335 	if (mod_delayed_work(addrconf_wq, &ifp->dad_work, delay))
336 		in6_ifa_put(ifp);
337 }
338 
339 static int snmp6_alloc_dev(struct inet6_dev *idev)
340 {
341 	int i;
342 
343 	idev->stats.ipv6 = alloc_percpu_gfp(struct ipstats_mib, GFP_KERNEL_ACCOUNT);
344 	if (!idev->stats.ipv6)
345 		goto err_ip;
346 
347 	for_each_possible_cpu(i) {
348 		struct ipstats_mib *addrconf_stats;
349 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
350 		u64_stats_init(&addrconf_stats->syncp);
351 	}
352 
353 
354 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
355 					GFP_KERNEL);
356 	if (!idev->stats.icmpv6dev)
357 		goto err_icmp;
358 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
359 					   GFP_KERNEL_ACCOUNT);
360 	if (!idev->stats.icmpv6msgdev)
361 		goto err_icmpmsg;
362 
363 	return 0;
364 
365 err_icmpmsg:
366 	kfree(idev->stats.icmpv6dev);
367 err_icmp:
368 	free_percpu(idev->stats.ipv6);
369 err_ip:
370 	return -ENOMEM;
371 }
372 
373 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
374 {
375 	struct inet6_dev *ndev;
376 	int err = -ENOMEM;
377 
378 	ASSERT_RTNL();
379 
380 	if (dev->mtu < IPV6_MIN_MTU && dev != blackhole_netdev)
381 		return ERR_PTR(-EINVAL);
382 
383 	ndev = kzalloc(sizeof(*ndev), GFP_KERNEL_ACCOUNT);
384 	if (!ndev)
385 		return ERR_PTR(err);
386 
387 	rwlock_init(&ndev->lock);
388 	ndev->dev = dev;
389 	INIT_LIST_HEAD(&ndev->addr_list);
390 	timer_setup(&ndev->rs_timer, addrconf_rs_timer, 0);
391 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
392 
393 	if (ndev->cnf.stable_secret.initialized)
394 		ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
395 
396 	ndev->cnf.mtu6 = dev->mtu;
397 	ndev->ra_mtu = 0;
398 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
399 	if (!ndev->nd_parms) {
400 		kfree(ndev);
401 		return ERR_PTR(err);
402 	}
403 	if (ndev->cnf.forwarding)
404 		dev_disable_lro(dev);
405 	/* We refer to the device */
406 	netdev_hold(dev, &ndev->dev_tracker, GFP_KERNEL);
407 
408 	if (snmp6_alloc_dev(ndev) < 0) {
409 		netdev_dbg(dev, "%s: cannot allocate memory for statistics\n",
410 			   __func__);
411 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
412 		netdev_put(dev, &ndev->dev_tracker);
413 		kfree(ndev);
414 		return ERR_PTR(err);
415 	}
416 
417 	if (dev != blackhole_netdev) {
418 		if (snmp6_register_dev(ndev) < 0) {
419 			netdev_dbg(dev, "%s: cannot create /proc/net/dev_snmp6/%s\n",
420 				   __func__, dev->name);
421 			goto err_release;
422 		}
423 	}
424 	/* One reference from device. */
425 	refcount_set(&ndev->refcnt, 1);
426 
427 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
428 		ndev->cnf.accept_dad = -1;
429 
430 #if IS_ENABLED(CONFIG_IPV6_SIT)
431 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
432 		pr_info("%s: Disabled Multicast RS\n", dev->name);
433 		ndev->cnf.rtr_solicits = 0;
434 	}
435 #endif
436 
437 	INIT_LIST_HEAD(&ndev->tempaddr_list);
438 	ndev->desync_factor = U32_MAX;
439 	if ((dev->flags&IFF_LOOPBACK) ||
440 	    dev->type == ARPHRD_TUNNEL ||
441 	    dev->type == ARPHRD_TUNNEL6 ||
442 	    dev->type == ARPHRD_SIT ||
443 	    dev->type == ARPHRD_NONE) {
444 		ndev->cnf.use_tempaddr = -1;
445 	}
446 
447 	ndev->token = in6addr_any;
448 
449 	if (netif_running(dev) && addrconf_link_ready(dev))
450 		ndev->if_flags |= IF_READY;
451 
452 	ipv6_mc_init_dev(ndev);
453 	ndev->tstamp = jiffies;
454 	if (dev != blackhole_netdev) {
455 		err = addrconf_sysctl_register(ndev);
456 		if (err) {
457 			ipv6_mc_destroy_dev(ndev);
458 			snmp6_unregister_dev(ndev);
459 			goto err_release;
460 		}
461 	}
462 	/* protected by rtnl_lock */
463 	rcu_assign_pointer(dev->ip6_ptr, ndev);
464 
465 	if (dev != blackhole_netdev) {
466 		/* Join interface-local all-node multicast group */
467 		ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
468 
469 		/* Join all-node multicast group */
470 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
471 
472 		/* Join all-router multicast group if forwarding is set */
473 		if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
474 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
475 	}
476 	return ndev;
477 
478 err_release:
479 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
480 	ndev->dead = 1;
481 	in6_dev_finish_destroy(ndev);
482 	return ERR_PTR(err);
483 }
484 
485 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
486 {
487 	struct inet6_dev *idev;
488 
489 	ASSERT_RTNL();
490 
491 	idev = __in6_dev_get(dev);
492 	if (!idev) {
493 		idev = ipv6_add_dev(dev);
494 		if (IS_ERR(idev))
495 			return idev;
496 	}
497 
498 	if (dev->flags&IFF_UP)
499 		ipv6_mc_up(idev);
500 	return idev;
501 }
502 
503 static int inet6_netconf_msgsize_devconf(int type)
504 {
505 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
506 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
507 	bool all = false;
508 
509 	if (type == NETCONFA_ALL)
510 		all = true;
511 
512 	if (all || type == NETCONFA_FORWARDING)
513 		size += nla_total_size(4);
514 #ifdef CONFIG_IPV6_MROUTE
515 	if (all || type == NETCONFA_MC_FORWARDING)
516 		size += nla_total_size(4);
517 #endif
518 	if (all || type == NETCONFA_PROXY_NEIGH)
519 		size += nla_total_size(4);
520 
521 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
522 		size += nla_total_size(4);
523 
524 	return size;
525 }
526 
527 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
528 				      struct ipv6_devconf *devconf, u32 portid,
529 				      u32 seq, int event, unsigned int flags,
530 				      int type)
531 {
532 	struct nlmsghdr  *nlh;
533 	struct netconfmsg *ncm;
534 	bool all = false;
535 
536 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
537 			flags);
538 	if (!nlh)
539 		return -EMSGSIZE;
540 
541 	if (type == NETCONFA_ALL)
542 		all = true;
543 
544 	ncm = nlmsg_data(nlh);
545 	ncm->ncm_family = AF_INET6;
546 
547 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
548 		goto nla_put_failure;
549 
550 	if (!devconf)
551 		goto out;
552 
553 	if ((all || type == NETCONFA_FORWARDING) &&
554 	    nla_put_s32(skb, NETCONFA_FORWARDING,
555 			READ_ONCE(devconf->forwarding)) < 0)
556 		goto nla_put_failure;
557 #ifdef CONFIG_IPV6_MROUTE
558 	if ((all || type == NETCONFA_MC_FORWARDING) &&
559 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
560 			atomic_read(&devconf->mc_forwarding)) < 0)
561 		goto nla_put_failure;
562 #endif
563 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
564 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH,
565 			READ_ONCE(devconf->proxy_ndp)) < 0)
566 		goto nla_put_failure;
567 
568 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
569 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
570 			READ_ONCE(devconf->ignore_routes_with_linkdown)) < 0)
571 		goto nla_put_failure;
572 
573 out:
574 	nlmsg_end(skb, nlh);
575 	return 0;
576 
577 nla_put_failure:
578 	nlmsg_cancel(skb, nlh);
579 	return -EMSGSIZE;
580 }
581 
582 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
583 				  int ifindex, struct ipv6_devconf *devconf)
584 {
585 	struct sk_buff *skb;
586 	int err = -ENOBUFS;
587 
588 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
589 	if (!skb)
590 		goto errout;
591 
592 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
593 					 event, 0, type);
594 	if (err < 0) {
595 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
596 		WARN_ON(err == -EMSGSIZE);
597 		kfree_skb(skb);
598 		goto errout;
599 	}
600 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
601 	return;
602 errout:
603 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
604 }
605 
606 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
607 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
608 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
609 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
610 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
611 };
612 
613 static int inet6_netconf_valid_get_req(struct sk_buff *skb,
614 				       const struct nlmsghdr *nlh,
615 				       struct nlattr **tb,
616 				       struct netlink_ext_ack *extack)
617 {
618 	int i, err;
619 
620 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(struct netconfmsg))) {
621 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf get request");
622 		return -EINVAL;
623 	}
624 
625 	if (!netlink_strict_get_check(skb))
626 		return nlmsg_parse_deprecated(nlh, sizeof(struct netconfmsg),
627 					      tb, NETCONFA_MAX,
628 					      devconf_ipv6_policy, extack);
629 
630 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct netconfmsg),
631 					    tb, NETCONFA_MAX,
632 					    devconf_ipv6_policy, extack);
633 	if (err)
634 		return err;
635 
636 	for (i = 0; i <= NETCONFA_MAX; i++) {
637 		if (!tb[i])
638 			continue;
639 
640 		switch (i) {
641 		case NETCONFA_IFINDEX:
642 			break;
643 		default:
644 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in netconf get request");
645 			return -EINVAL;
646 		}
647 	}
648 
649 	return 0;
650 }
651 
652 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
653 				     struct nlmsghdr *nlh,
654 				     struct netlink_ext_ack *extack)
655 {
656 	struct net *net = sock_net(in_skb->sk);
657 	struct nlattr *tb[NETCONFA_MAX+1];
658 	struct inet6_dev *in6_dev = NULL;
659 	struct net_device *dev = NULL;
660 	struct sk_buff *skb;
661 	struct ipv6_devconf *devconf;
662 	int ifindex;
663 	int err;
664 
665 	err = inet6_netconf_valid_get_req(in_skb, nlh, tb, extack);
666 	if (err < 0)
667 		return err;
668 
669 	if (!tb[NETCONFA_IFINDEX])
670 		return -EINVAL;
671 
672 	err = -EINVAL;
673 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
674 	switch (ifindex) {
675 	case NETCONFA_IFINDEX_ALL:
676 		devconf = net->ipv6.devconf_all;
677 		break;
678 	case NETCONFA_IFINDEX_DEFAULT:
679 		devconf = net->ipv6.devconf_dflt;
680 		break;
681 	default:
682 		dev = dev_get_by_index(net, ifindex);
683 		if (!dev)
684 			return -EINVAL;
685 		in6_dev = in6_dev_get(dev);
686 		if (!in6_dev)
687 			goto errout;
688 		devconf = &in6_dev->cnf;
689 		break;
690 	}
691 
692 	err = -ENOBUFS;
693 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
694 	if (!skb)
695 		goto errout;
696 
697 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
698 					 NETLINK_CB(in_skb).portid,
699 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
700 					 NETCONFA_ALL);
701 	if (err < 0) {
702 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
703 		WARN_ON(err == -EMSGSIZE);
704 		kfree_skb(skb);
705 		goto errout;
706 	}
707 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
708 errout:
709 	if (in6_dev)
710 		in6_dev_put(in6_dev);
711 	dev_put(dev);
712 	return err;
713 }
714 
715 /* Combine dev_addr_genid and dev_base_seq to detect changes.
716  */
717 static u32 inet6_base_seq(const struct net *net)
718 {
719 	u32 res = atomic_read(&net->ipv6.dev_addr_genid) +
720 		  READ_ONCE(net->dev_base_seq);
721 
722 	/* Must not return 0 (see nl_dump_check_consistent()).
723 	 * Chose a value far away from 0.
724 	 */
725 	if (!res)
726 		res = 0x80000000;
727 	return res;
728 }
729 
730 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
731 				      struct netlink_callback *cb)
732 {
733 	const struct nlmsghdr *nlh = cb->nlh;
734 	struct net *net = sock_net(skb->sk);
735 	struct {
736 		unsigned long ifindex;
737 		unsigned int all_default;
738 	} *ctx = (void *)cb->ctx;
739 	struct net_device *dev;
740 	struct inet6_dev *idev;
741 	int err = 0;
742 
743 	if (cb->strict_check) {
744 		struct netlink_ext_ack *extack = cb->extack;
745 		struct netconfmsg *ncm;
746 
747 		if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) {
748 			NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf dump request");
749 			return -EINVAL;
750 		}
751 
752 		if (nlmsg_attrlen(nlh, sizeof(*ncm))) {
753 			NL_SET_ERR_MSG_MOD(extack, "Invalid data after header in netconf dump request");
754 			return -EINVAL;
755 		}
756 	}
757 
758 	rcu_read_lock();
759 	for_each_netdev_dump(net, dev, ctx->ifindex) {
760 		idev = __in6_dev_get(dev);
761 		if (!idev)
762 			continue;
763 		err = inet6_netconf_fill_devconf(skb, dev->ifindex,
764 					         &idev->cnf,
765 						 NETLINK_CB(cb->skb).portid,
766 						 nlh->nlmsg_seq,
767 						 RTM_NEWNETCONF,
768 						 NLM_F_MULTI,
769 						 NETCONFA_ALL);
770 		if (err < 0)
771 			goto done;
772 	}
773 	if (ctx->all_default == 0) {
774 		err = inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
775 						 net->ipv6.devconf_all,
776 						 NETLINK_CB(cb->skb).portid,
777 						 nlh->nlmsg_seq,
778 						 RTM_NEWNETCONF, NLM_F_MULTI,
779 						 NETCONFA_ALL);
780 		if (err < 0)
781 			goto done;
782 		ctx->all_default++;
783 	}
784 	if (ctx->all_default == 1) {
785 		err = inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
786 						 net->ipv6.devconf_dflt,
787 						 NETLINK_CB(cb->skb).portid,
788 						 nlh->nlmsg_seq,
789 						 RTM_NEWNETCONF, NLM_F_MULTI,
790 						 NETCONFA_ALL);
791 		if (err < 0)
792 			goto done;
793 		ctx->all_default++;
794 	}
795 done:
796 	rcu_read_unlock();
797 	return err;
798 }
799 
800 #ifdef CONFIG_SYSCTL
801 static void dev_forward_change(struct inet6_dev *idev)
802 {
803 	struct net_device *dev;
804 	struct inet6_ifaddr *ifa;
805 	LIST_HEAD(tmp_addr_list);
806 
807 	if (!idev)
808 		return;
809 	dev = idev->dev;
810 	if (idev->cnf.forwarding)
811 		dev_disable_lro(dev);
812 	if (dev->flags & IFF_MULTICAST) {
813 		if (idev->cnf.forwarding) {
814 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
815 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
816 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
817 		} else {
818 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
819 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
820 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
821 		}
822 	}
823 
824 	read_lock_bh(&idev->lock);
825 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
826 		if (ifa->flags&IFA_F_TENTATIVE)
827 			continue;
828 		list_add_tail(&ifa->if_list_aux, &tmp_addr_list);
829 	}
830 	read_unlock_bh(&idev->lock);
831 
832 	while (!list_empty(&tmp_addr_list)) {
833 		ifa = list_first_entry(&tmp_addr_list,
834 				       struct inet6_ifaddr, if_list_aux);
835 		list_del(&ifa->if_list_aux);
836 		if (idev->cnf.forwarding)
837 			addrconf_join_anycast(ifa);
838 		else
839 			addrconf_leave_anycast(ifa);
840 	}
841 
842 	inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
843 				     NETCONFA_FORWARDING,
844 				     dev->ifindex, &idev->cnf);
845 }
846 
847 
848 static void addrconf_forward_change(struct net *net, __s32 newf)
849 {
850 	struct net_device *dev;
851 	struct inet6_dev *idev;
852 
853 	for_each_netdev(net, dev) {
854 		idev = __in6_dev_get(dev);
855 		if (idev) {
856 			int changed = (!idev->cnf.forwarding) ^ (!newf);
857 
858 			WRITE_ONCE(idev->cnf.forwarding, newf);
859 			if (changed)
860 				dev_forward_change(idev);
861 		}
862 	}
863 }
864 
865 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
866 {
867 	struct net *net;
868 	int old;
869 
870 	if (!rtnl_trylock())
871 		return restart_syscall();
872 
873 	net = (struct net *)table->extra2;
874 	old = *p;
875 	WRITE_ONCE(*p, newf);
876 
877 	if (p == &net->ipv6.devconf_dflt->forwarding) {
878 		if ((!newf) ^ (!old))
879 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
880 						     NETCONFA_FORWARDING,
881 						     NETCONFA_IFINDEX_DEFAULT,
882 						     net->ipv6.devconf_dflt);
883 		rtnl_unlock();
884 		return 0;
885 	}
886 
887 	if (p == &net->ipv6.devconf_all->forwarding) {
888 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
889 
890 		WRITE_ONCE(net->ipv6.devconf_dflt->forwarding, newf);
891 		if ((!newf) ^ (!old_dflt))
892 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
893 						     NETCONFA_FORWARDING,
894 						     NETCONFA_IFINDEX_DEFAULT,
895 						     net->ipv6.devconf_dflt);
896 
897 		addrconf_forward_change(net, newf);
898 		if ((!newf) ^ (!old))
899 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
900 						     NETCONFA_FORWARDING,
901 						     NETCONFA_IFINDEX_ALL,
902 						     net->ipv6.devconf_all);
903 	} else if ((!newf) ^ (!old))
904 		dev_forward_change((struct inet6_dev *)table->extra1);
905 	rtnl_unlock();
906 
907 	if (newf)
908 		rt6_purge_dflt_routers(net);
909 	return 1;
910 }
911 
912 static void addrconf_linkdown_change(struct net *net, __s32 newf)
913 {
914 	struct net_device *dev;
915 	struct inet6_dev *idev;
916 
917 	for_each_netdev(net, dev) {
918 		idev = __in6_dev_get(dev);
919 		if (idev) {
920 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
921 
922 			WRITE_ONCE(idev->cnf.ignore_routes_with_linkdown, newf);
923 			if (changed)
924 				inet6_netconf_notify_devconf(dev_net(dev),
925 							     RTM_NEWNETCONF,
926 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
927 							     dev->ifindex,
928 							     &idev->cnf);
929 		}
930 	}
931 }
932 
933 static int addrconf_fixup_linkdown(struct ctl_table *table, int *p, int newf)
934 {
935 	struct net *net;
936 	int old;
937 
938 	if (!rtnl_trylock())
939 		return restart_syscall();
940 
941 	net = (struct net *)table->extra2;
942 	old = *p;
943 	WRITE_ONCE(*p, newf);
944 
945 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
946 		if ((!newf) ^ (!old))
947 			inet6_netconf_notify_devconf(net,
948 						     RTM_NEWNETCONF,
949 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
950 						     NETCONFA_IFINDEX_DEFAULT,
951 						     net->ipv6.devconf_dflt);
952 		rtnl_unlock();
953 		return 0;
954 	}
955 
956 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
957 		WRITE_ONCE(net->ipv6.devconf_dflt->ignore_routes_with_linkdown, newf);
958 		addrconf_linkdown_change(net, newf);
959 		if ((!newf) ^ (!old))
960 			inet6_netconf_notify_devconf(net,
961 						     RTM_NEWNETCONF,
962 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
963 						     NETCONFA_IFINDEX_ALL,
964 						     net->ipv6.devconf_all);
965 	}
966 	rtnl_unlock();
967 
968 	return 1;
969 }
970 
971 #endif
972 
973 /* Nobody refers to this ifaddr, destroy it */
974 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
975 {
976 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
977 
978 #ifdef NET_REFCNT_DEBUG
979 	pr_debug("%s\n", __func__);
980 #endif
981 
982 	in6_dev_put(ifp->idev);
983 
984 	if (cancel_delayed_work(&ifp->dad_work))
985 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
986 			  ifp);
987 
988 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
989 		pr_warn("Freeing alive inet6 address %p\n", ifp);
990 		return;
991 	}
992 
993 	kfree_rcu(ifp, rcu);
994 }
995 
996 static void
997 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
998 {
999 	struct list_head *p;
1000 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
1001 
1002 	/*
1003 	 * Each device address list is sorted in order of scope -
1004 	 * global before linklocal.
1005 	 */
1006 	list_for_each(p, &idev->addr_list) {
1007 		struct inet6_ifaddr *ifa
1008 			= list_entry(p, struct inet6_ifaddr, if_list);
1009 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
1010 			break;
1011 	}
1012 
1013 	list_add_tail_rcu(&ifp->if_list, p);
1014 }
1015 
1016 static u32 inet6_addr_hash(const struct net *net, const struct in6_addr *addr)
1017 {
1018 	u32 val = ipv6_addr_hash(addr) ^ net_hash_mix(net);
1019 
1020 	return hash_32(val, IN6_ADDR_HSIZE_SHIFT);
1021 }
1022 
1023 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1024 			       struct net_device *dev, unsigned int hash)
1025 {
1026 	struct inet6_ifaddr *ifp;
1027 
1028 	hlist_for_each_entry(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
1029 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1030 			if (!dev || ifp->idev->dev == dev)
1031 				return true;
1032 		}
1033 	}
1034 	return false;
1035 }
1036 
1037 static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
1038 {
1039 	struct net *net = dev_net(dev);
1040 	unsigned int hash = inet6_addr_hash(net, &ifa->addr);
1041 	int err = 0;
1042 
1043 	spin_lock_bh(&net->ipv6.addrconf_hash_lock);
1044 
1045 	/* Ignore adding duplicate addresses on an interface */
1046 	if (ipv6_chk_same_addr(net, &ifa->addr, dev, hash)) {
1047 		netdev_dbg(dev, "ipv6_add_addr: already assigned\n");
1048 		err = -EEXIST;
1049 	} else {
1050 		hlist_add_head_rcu(&ifa->addr_lst, &net->ipv6.inet6_addr_lst[hash]);
1051 	}
1052 
1053 	spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
1054 
1055 	return err;
1056 }
1057 
1058 /* On success it returns ifp with increased reference count */
1059 
1060 static struct inet6_ifaddr *
1061 ipv6_add_addr(struct inet6_dev *idev, struct ifa6_config *cfg,
1062 	      bool can_block, struct netlink_ext_ack *extack)
1063 {
1064 	gfp_t gfp_flags = can_block ? GFP_KERNEL : GFP_ATOMIC;
1065 	int addr_type = ipv6_addr_type(cfg->pfx);
1066 	struct net *net = dev_net(idev->dev);
1067 	struct inet6_ifaddr *ifa = NULL;
1068 	struct fib6_info *f6i = NULL;
1069 	int err = 0;
1070 
1071 	if (addr_type == IPV6_ADDR_ANY) {
1072 		NL_SET_ERR_MSG_MOD(extack, "Invalid address");
1073 		return ERR_PTR(-EADDRNOTAVAIL);
1074 	} else if (addr_type & IPV6_ADDR_MULTICAST &&
1075 		   !(cfg->ifa_flags & IFA_F_MCAUTOJOIN)) {
1076 		NL_SET_ERR_MSG_MOD(extack, "Cannot assign multicast address without \"IFA_F_MCAUTOJOIN\" flag");
1077 		return ERR_PTR(-EADDRNOTAVAIL);
1078 	} else if (!(idev->dev->flags & IFF_LOOPBACK) &&
1079 		   !netif_is_l3_master(idev->dev) &&
1080 		   addr_type & IPV6_ADDR_LOOPBACK) {
1081 		NL_SET_ERR_MSG_MOD(extack, "Cannot assign loopback address on this device");
1082 		return ERR_PTR(-EADDRNOTAVAIL);
1083 	}
1084 
1085 	if (idev->dead) {
1086 		NL_SET_ERR_MSG_MOD(extack, "device is going away");
1087 		err = -ENODEV;
1088 		goto out;
1089 	}
1090 
1091 	if (idev->cnf.disable_ipv6) {
1092 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
1093 		err = -EACCES;
1094 		goto out;
1095 	}
1096 
1097 	/* validator notifier needs to be blocking;
1098 	 * do not call in atomic context
1099 	 */
1100 	if (can_block) {
1101 		struct in6_validator_info i6vi = {
1102 			.i6vi_addr = *cfg->pfx,
1103 			.i6vi_dev = idev,
1104 			.extack = extack,
1105 		};
1106 
1107 		err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
1108 		err = notifier_to_errno(err);
1109 		if (err < 0)
1110 			goto out;
1111 	}
1112 
1113 	ifa = kzalloc(sizeof(*ifa), gfp_flags | __GFP_ACCOUNT);
1114 	if (!ifa) {
1115 		err = -ENOBUFS;
1116 		goto out;
1117 	}
1118 
1119 	f6i = addrconf_f6i_alloc(net, idev, cfg->pfx, false, gfp_flags, extack);
1120 	if (IS_ERR(f6i)) {
1121 		err = PTR_ERR(f6i);
1122 		f6i = NULL;
1123 		goto out;
1124 	}
1125 
1126 	neigh_parms_data_state_setall(idev->nd_parms);
1127 
1128 	ifa->addr = *cfg->pfx;
1129 	if (cfg->peer_pfx)
1130 		ifa->peer_addr = *cfg->peer_pfx;
1131 
1132 	spin_lock_init(&ifa->lock);
1133 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1134 	INIT_HLIST_NODE(&ifa->addr_lst);
1135 	ifa->scope = cfg->scope;
1136 	ifa->prefix_len = cfg->plen;
1137 	ifa->rt_priority = cfg->rt_priority;
1138 	ifa->flags = cfg->ifa_flags;
1139 	ifa->ifa_proto = cfg->ifa_proto;
1140 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1141 	if (!(cfg->ifa_flags & IFA_F_NODAD))
1142 		ifa->flags |= IFA_F_TENTATIVE;
1143 	ifa->valid_lft = cfg->valid_lft;
1144 	ifa->prefered_lft = cfg->preferred_lft;
1145 	ifa->cstamp = ifa->tstamp = jiffies;
1146 	ifa->tokenized = false;
1147 
1148 	ifa->rt = f6i;
1149 
1150 	ifa->idev = idev;
1151 	in6_dev_hold(idev);
1152 
1153 	/* For caller */
1154 	refcount_set(&ifa->refcnt, 1);
1155 
1156 	rcu_read_lock();
1157 
1158 	err = ipv6_add_addr_hash(idev->dev, ifa);
1159 	if (err < 0) {
1160 		rcu_read_unlock();
1161 		goto out;
1162 	}
1163 
1164 	write_lock_bh(&idev->lock);
1165 
1166 	/* Add to inet6_dev unicast addr list. */
1167 	ipv6_link_dev_addr(idev, ifa);
1168 
1169 	if (ifa->flags&IFA_F_TEMPORARY) {
1170 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1171 		in6_ifa_hold(ifa);
1172 	}
1173 
1174 	in6_ifa_hold(ifa);
1175 	write_unlock_bh(&idev->lock);
1176 
1177 	rcu_read_unlock();
1178 
1179 	inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1180 out:
1181 	if (unlikely(err < 0)) {
1182 		fib6_info_release(f6i);
1183 
1184 		if (ifa) {
1185 			if (ifa->idev)
1186 				in6_dev_put(ifa->idev);
1187 			kfree(ifa);
1188 		}
1189 		ifa = ERR_PTR(err);
1190 	}
1191 
1192 	return ifa;
1193 }
1194 
1195 enum cleanup_prefix_rt_t {
1196 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1197 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1198 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1199 };
1200 
1201 /*
1202  * Check, whether the prefix for ifp would still need a prefix route
1203  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1204  * constants.
1205  *
1206  * 1) we don't purge prefix if address was not permanent.
1207  *    prefix is managed by its own lifetime.
1208  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1209  * 3) if there are no addresses, delete prefix.
1210  * 4) if there are still other permanent address(es),
1211  *    corresponding prefix is still permanent.
1212  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1213  *    don't purge the prefix, assume user space is managing it.
1214  * 6) otherwise, update prefix lifetime to the
1215  *    longest valid lifetime among the corresponding
1216  *    addresses on the device.
1217  *    Note: subsequent RA will update lifetime.
1218  **/
1219 static enum cleanup_prefix_rt_t
1220 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1221 {
1222 	struct inet6_ifaddr *ifa;
1223 	struct inet6_dev *idev = ifp->idev;
1224 	unsigned long lifetime;
1225 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1226 
1227 	*expires = jiffies;
1228 
1229 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1230 		if (ifa == ifp)
1231 			continue;
1232 		if (ifa->prefix_len != ifp->prefix_len ||
1233 		    !ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1234 				       ifp->prefix_len))
1235 			continue;
1236 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1237 			return CLEANUP_PREFIX_RT_NOP;
1238 
1239 		action = CLEANUP_PREFIX_RT_EXPIRE;
1240 
1241 		spin_lock(&ifa->lock);
1242 
1243 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1244 		/*
1245 		 * Note: Because this address is
1246 		 * not permanent, lifetime <
1247 		 * LONG_MAX / HZ here.
1248 		 */
1249 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1250 			*expires = ifa->tstamp + lifetime * HZ;
1251 		spin_unlock(&ifa->lock);
1252 	}
1253 
1254 	return action;
1255 }
1256 
1257 static void
1258 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires,
1259 		     bool del_rt, bool del_peer)
1260 {
1261 	struct fib6_table *table;
1262 	struct fib6_info *f6i;
1263 
1264 	f6i = addrconf_get_prefix_route(del_peer ? &ifp->peer_addr : &ifp->addr,
1265 					ifp->prefix_len,
1266 					ifp->idev->dev, 0, RTF_DEFAULT, true);
1267 	if (f6i) {
1268 		if (del_rt)
1269 			ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
1270 		else {
1271 			if (!(f6i->fib6_flags & RTF_EXPIRES)) {
1272 				table = f6i->fib6_table;
1273 				spin_lock_bh(&table->tb6_lock);
1274 
1275 				fib6_set_expires(f6i, expires);
1276 				fib6_add_gc_list(f6i);
1277 
1278 				spin_unlock_bh(&table->tb6_lock);
1279 			}
1280 			fib6_info_release(f6i);
1281 		}
1282 	}
1283 }
1284 
1285 
1286 /* This function wants to get referenced ifp and releases it before return */
1287 
1288 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1289 {
1290 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1291 	struct net *net = dev_net(ifp->idev->dev);
1292 	unsigned long expires;
1293 	int state;
1294 
1295 	ASSERT_RTNL();
1296 
1297 	spin_lock_bh(&ifp->lock);
1298 	state = ifp->state;
1299 	ifp->state = INET6_IFADDR_STATE_DEAD;
1300 	spin_unlock_bh(&ifp->lock);
1301 
1302 	if (state == INET6_IFADDR_STATE_DEAD)
1303 		goto out;
1304 
1305 	spin_lock_bh(&net->ipv6.addrconf_hash_lock);
1306 	hlist_del_init_rcu(&ifp->addr_lst);
1307 	spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
1308 
1309 	write_lock_bh(&ifp->idev->lock);
1310 
1311 	if (ifp->flags&IFA_F_TEMPORARY) {
1312 		list_del(&ifp->tmp_list);
1313 		if (ifp->ifpub) {
1314 			in6_ifa_put(ifp->ifpub);
1315 			ifp->ifpub = NULL;
1316 		}
1317 		__in6_ifa_put(ifp);
1318 	}
1319 
1320 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1321 		action = check_cleanup_prefix_route(ifp, &expires);
1322 
1323 	list_del_rcu(&ifp->if_list);
1324 	__in6_ifa_put(ifp);
1325 
1326 	write_unlock_bh(&ifp->idev->lock);
1327 
1328 	addrconf_del_dad_work(ifp);
1329 
1330 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1331 
1332 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1333 
1334 	if (action != CLEANUP_PREFIX_RT_NOP) {
1335 		cleanup_prefix_route(ifp, expires,
1336 			action == CLEANUP_PREFIX_RT_DEL, false);
1337 	}
1338 
1339 	/* clean up prefsrc entries */
1340 	rt6_remove_prefsrc(ifp);
1341 out:
1342 	in6_ifa_put(ifp);
1343 }
1344 
1345 static unsigned long ipv6_get_regen_advance(const struct inet6_dev *idev)
1346 {
1347 	return READ_ONCE(idev->cnf.regen_min_advance) +
1348 		READ_ONCE(idev->cnf.regen_max_retry) *
1349 		READ_ONCE(idev->cnf.dad_transmits) *
1350 		max(NEIGH_VAR(idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
1351 }
1352 
1353 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, bool block)
1354 {
1355 	struct inet6_dev *idev = ifp->idev;
1356 	unsigned long tmp_tstamp, age;
1357 	unsigned long regen_advance;
1358 	unsigned long now = jiffies;
1359 	u32 if_public_preferred_lft;
1360 	s32 cnf_temp_preferred_lft;
1361 	struct inet6_ifaddr *ift;
1362 	struct ifa6_config cfg;
1363 	long max_desync_factor;
1364 	struct in6_addr addr;
1365 	int ret = 0;
1366 
1367 	write_lock_bh(&idev->lock);
1368 
1369 retry:
1370 	in6_dev_hold(idev);
1371 	if (READ_ONCE(idev->cnf.use_tempaddr) <= 0) {
1372 		write_unlock_bh(&idev->lock);
1373 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1374 		in6_dev_put(idev);
1375 		ret = -1;
1376 		goto out;
1377 	}
1378 	spin_lock_bh(&ifp->lock);
1379 	if (ifp->regen_count++ >= READ_ONCE(idev->cnf.regen_max_retry)) {
1380 		WRITE_ONCE(idev->cnf.use_tempaddr, -1);	/*XXX*/
1381 		spin_unlock_bh(&ifp->lock);
1382 		write_unlock_bh(&idev->lock);
1383 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1384 			__func__);
1385 		in6_dev_put(idev);
1386 		ret = -1;
1387 		goto out;
1388 	}
1389 	in6_ifa_hold(ifp);
1390 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1391 	ipv6_gen_rnd_iid(&addr);
1392 
1393 	age = (now - ifp->tstamp) / HZ;
1394 
1395 	regen_advance = ipv6_get_regen_advance(idev);
1396 
1397 	/* recalculate max_desync_factor each time and update
1398 	 * idev->desync_factor if it's larger
1399 	 */
1400 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1401 	max_desync_factor = min_t(long,
1402 				  READ_ONCE(idev->cnf.max_desync_factor),
1403 				  cnf_temp_preferred_lft - regen_advance);
1404 
1405 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1406 		if (max_desync_factor > 0) {
1407 			get_random_bytes(&idev->desync_factor,
1408 					 sizeof(idev->desync_factor));
1409 			idev->desync_factor %= max_desync_factor;
1410 		} else {
1411 			idev->desync_factor = 0;
1412 		}
1413 	}
1414 
1415 	if_public_preferred_lft = ifp->prefered_lft;
1416 
1417 	memset(&cfg, 0, sizeof(cfg));
1418 	cfg.valid_lft = min_t(__u32, ifp->valid_lft,
1419 			      READ_ONCE(idev->cnf.temp_valid_lft) + age);
1420 	cfg.preferred_lft = cnf_temp_preferred_lft + age - idev->desync_factor;
1421 	cfg.preferred_lft = min_t(__u32, if_public_preferred_lft, cfg.preferred_lft);
1422 	cfg.preferred_lft = min_t(__u32, cfg.valid_lft, cfg.preferred_lft);
1423 
1424 	cfg.plen = ifp->prefix_len;
1425 	tmp_tstamp = ifp->tstamp;
1426 	spin_unlock_bh(&ifp->lock);
1427 
1428 	write_unlock_bh(&idev->lock);
1429 
1430 	/* From RFC 4941:
1431 	 *
1432 	 *     A temporary address is created only if this calculated Preferred
1433 	 *     Lifetime is greater than REGEN_ADVANCE time units.  In
1434 	 *     particular, an implementation must not create a temporary address
1435 	 *     with a zero Preferred Lifetime.
1436 	 *
1437 	 *     ...
1438 	 *
1439 	 *     When creating a temporary address, the lifetime values MUST be
1440 	 *     derived from the corresponding prefix as follows:
1441 	 *
1442 	 *     ...
1443 	 *
1444 	 *     *  Its Preferred Lifetime is the lower of the Preferred Lifetime
1445 	 *        of the public address or TEMP_PREFERRED_LIFETIME -
1446 	 *        DESYNC_FACTOR.
1447 	 *
1448 	 * To comply with the RFC's requirements, clamp the preferred lifetime
1449 	 * to a minimum of regen_advance, unless that would exceed valid_lft or
1450 	 * ifp->prefered_lft.
1451 	 *
1452 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1453 	 * temporary addresses being generated.
1454 	 */
1455 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1456 	if (cfg.preferred_lft <= regen_advance + age) {
1457 		cfg.preferred_lft = regen_advance + age + 1;
1458 		if (cfg.preferred_lft > cfg.valid_lft ||
1459 		    cfg.preferred_lft > if_public_preferred_lft) {
1460 			in6_ifa_put(ifp);
1461 			in6_dev_put(idev);
1462 			ret = -1;
1463 			goto out;
1464 		}
1465 	}
1466 
1467 	cfg.ifa_flags = IFA_F_TEMPORARY;
1468 	/* set in addrconf_prefix_rcv() */
1469 	if (ifp->flags & IFA_F_OPTIMISTIC)
1470 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
1471 
1472 	cfg.pfx = &addr;
1473 	cfg.scope = ipv6_addr_scope(cfg.pfx);
1474 
1475 	ift = ipv6_add_addr(idev, &cfg, block, NULL);
1476 	if (IS_ERR(ift)) {
1477 		in6_ifa_put(ifp);
1478 		in6_dev_put(idev);
1479 		pr_info("%s: retry temporary address regeneration\n", __func__);
1480 		write_lock_bh(&idev->lock);
1481 		goto retry;
1482 	}
1483 
1484 	spin_lock_bh(&ift->lock);
1485 	ift->ifpub = ifp;
1486 	ift->cstamp = now;
1487 	ift->tstamp = tmp_tstamp;
1488 	spin_unlock_bh(&ift->lock);
1489 
1490 	addrconf_dad_start(ift);
1491 	in6_ifa_put(ift);
1492 	in6_dev_put(idev);
1493 out:
1494 	return ret;
1495 }
1496 
1497 /*
1498  *	Choose an appropriate source address (RFC3484)
1499  */
1500 enum {
1501 	IPV6_SADDR_RULE_INIT = 0,
1502 	IPV6_SADDR_RULE_LOCAL,
1503 	IPV6_SADDR_RULE_SCOPE,
1504 	IPV6_SADDR_RULE_PREFERRED,
1505 #ifdef CONFIG_IPV6_MIP6
1506 	IPV6_SADDR_RULE_HOA,
1507 #endif
1508 	IPV6_SADDR_RULE_OIF,
1509 	IPV6_SADDR_RULE_LABEL,
1510 	IPV6_SADDR_RULE_PRIVACY,
1511 	IPV6_SADDR_RULE_ORCHID,
1512 	IPV6_SADDR_RULE_PREFIX,
1513 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1514 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1515 #endif
1516 	IPV6_SADDR_RULE_MAX
1517 };
1518 
1519 struct ipv6_saddr_score {
1520 	int			rule;
1521 	int			addr_type;
1522 	struct inet6_ifaddr	*ifa;
1523 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1524 	int			scopedist;
1525 	int			matchlen;
1526 };
1527 
1528 struct ipv6_saddr_dst {
1529 	const struct in6_addr *addr;
1530 	int ifindex;
1531 	int scope;
1532 	int label;
1533 	unsigned int prefs;
1534 };
1535 
1536 static inline int ipv6_saddr_preferred(int type)
1537 {
1538 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1539 		return 1;
1540 	return 0;
1541 }
1542 
1543 static bool ipv6_use_optimistic_addr(const struct net *net,
1544 				     const struct inet6_dev *idev)
1545 {
1546 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1547 	if (!idev)
1548 		return false;
1549 	if (!READ_ONCE(net->ipv6.devconf_all->optimistic_dad) &&
1550 	    !READ_ONCE(idev->cnf.optimistic_dad))
1551 		return false;
1552 	if (!READ_ONCE(net->ipv6.devconf_all->use_optimistic) &&
1553 	    !READ_ONCE(idev->cnf.use_optimistic))
1554 		return false;
1555 
1556 	return true;
1557 #else
1558 	return false;
1559 #endif
1560 }
1561 
1562 static bool ipv6_allow_optimistic_dad(const struct net *net,
1563 				      const struct inet6_dev *idev)
1564 {
1565 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1566 	if (!idev)
1567 		return false;
1568 	if (!READ_ONCE(net->ipv6.devconf_all->optimistic_dad) &&
1569 	    !READ_ONCE(idev->cnf.optimistic_dad))
1570 		return false;
1571 
1572 	return true;
1573 #else
1574 	return false;
1575 #endif
1576 }
1577 
1578 static int ipv6_get_saddr_eval(struct net *net,
1579 			       struct ipv6_saddr_score *score,
1580 			       struct ipv6_saddr_dst *dst,
1581 			       int i)
1582 {
1583 	int ret;
1584 
1585 	if (i <= score->rule) {
1586 		switch (i) {
1587 		case IPV6_SADDR_RULE_SCOPE:
1588 			ret = score->scopedist;
1589 			break;
1590 		case IPV6_SADDR_RULE_PREFIX:
1591 			ret = score->matchlen;
1592 			break;
1593 		default:
1594 			ret = !!test_bit(i, score->scorebits);
1595 		}
1596 		goto out;
1597 	}
1598 
1599 	switch (i) {
1600 	case IPV6_SADDR_RULE_INIT:
1601 		/* Rule 0: remember if hiscore is not ready yet */
1602 		ret = !!score->ifa;
1603 		break;
1604 	case IPV6_SADDR_RULE_LOCAL:
1605 		/* Rule 1: Prefer same address */
1606 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1607 		break;
1608 	case IPV6_SADDR_RULE_SCOPE:
1609 		/* Rule 2: Prefer appropriate scope
1610 		 *
1611 		 *      ret
1612 		 *       ^
1613 		 *    -1 |  d 15
1614 		 *    ---+--+-+---> scope
1615 		 *       |
1616 		 *       |             d is scope of the destination.
1617 		 *  B-d  |  \
1618 		 *       |   \      <- smaller scope is better if
1619 		 *  B-15 |    \        if scope is enough for destination.
1620 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1621 		 * d-C-1 | /
1622 		 *       |/         <- greater is better
1623 		 *   -C  /             if scope is not enough for destination.
1624 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1625 		 *
1626 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1627 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1628 		 * Assume B = 0 and we get C > 29.
1629 		 */
1630 		ret = __ipv6_addr_src_scope(score->addr_type);
1631 		if (ret >= dst->scope)
1632 			ret = -ret;
1633 		else
1634 			ret -= 128;	/* 30 is enough */
1635 		score->scopedist = ret;
1636 		break;
1637 	case IPV6_SADDR_RULE_PREFERRED:
1638 	    {
1639 		/* Rule 3: Avoid deprecated and optimistic addresses */
1640 		u8 avoid = IFA_F_DEPRECATED;
1641 
1642 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1643 			avoid |= IFA_F_OPTIMISTIC;
1644 		ret = ipv6_saddr_preferred(score->addr_type) ||
1645 		      !(score->ifa->flags & avoid);
1646 		break;
1647 	    }
1648 #ifdef CONFIG_IPV6_MIP6
1649 	case IPV6_SADDR_RULE_HOA:
1650 	    {
1651 		/* Rule 4: Prefer home address */
1652 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1653 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1654 		break;
1655 	    }
1656 #endif
1657 	case IPV6_SADDR_RULE_OIF:
1658 		/* Rule 5: Prefer outgoing interface */
1659 		ret = (!dst->ifindex ||
1660 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1661 		break;
1662 	case IPV6_SADDR_RULE_LABEL:
1663 		/* Rule 6: Prefer matching label */
1664 		ret = ipv6_addr_label(net,
1665 				      &score->ifa->addr, score->addr_type,
1666 				      score->ifa->idev->dev->ifindex) == dst->label;
1667 		break;
1668 	case IPV6_SADDR_RULE_PRIVACY:
1669 	    {
1670 		/* Rule 7: Prefer public address
1671 		 * Note: prefer temporary address if use_tempaddr >= 2
1672 		 */
1673 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1674 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1675 				READ_ONCE(score->ifa->idev->cnf.use_tempaddr) >= 2;
1676 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1677 		break;
1678 	    }
1679 	case IPV6_SADDR_RULE_ORCHID:
1680 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1681 		 *	    non-ORCHID vs non-ORCHID
1682 		 */
1683 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1684 			ipv6_addr_orchid(dst->addr));
1685 		break;
1686 	case IPV6_SADDR_RULE_PREFIX:
1687 		/* Rule 8: Use longest matching prefix */
1688 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1689 		if (ret > score->ifa->prefix_len)
1690 			ret = score->ifa->prefix_len;
1691 		score->matchlen = ret;
1692 		break;
1693 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1694 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1695 		/* Optimistic addresses still have lower precedence than other
1696 		 * preferred addresses.
1697 		 */
1698 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1699 		break;
1700 #endif
1701 	default:
1702 		ret = 0;
1703 	}
1704 
1705 	if (ret)
1706 		__set_bit(i, score->scorebits);
1707 	score->rule = i;
1708 out:
1709 	return ret;
1710 }
1711 
1712 static int __ipv6_dev_get_saddr(struct net *net,
1713 				struct ipv6_saddr_dst *dst,
1714 				struct inet6_dev *idev,
1715 				struct ipv6_saddr_score *scores,
1716 				int hiscore_idx)
1717 {
1718 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1719 
1720 	list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1721 		int i;
1722 
1723 		/*
1724 		 * - Tentative Address (RFC2462 section 5.4)
1725 		 *  - A tentative address is not considered
1726 		 *    "assigned to an interface" in the traditional
1727 		 *    sense, unless it is also flagged as optimistic.
1728 		 * - Candidate Source Address (section 4)
1729 		 *  - In any case, anycast addresses, multicast
1730 		 *    addresses, and the unspecified address MUST
1731 		 *    NOT be included in a candidate set.
1732 		 */
1733 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1734 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1735 			continue;
1736 
1737 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1738 
1739 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1740 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1741 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1742 					    idev->dev->name);
1743 			continue;
1744 		}
1745 
1746 		score->rule = -1;
1747 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1748 
1749 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1750 			int minihiscore, miniscore;
1751 
1752 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1753 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1754 
1755 			if (minihiscore > miniscore) {
1756 				if (i == IPV6_SADDR_RULE_SCOPE &&
1757 				    score->scopedist > 0) {
1758 					/*
1759 					 * special case:
1760 					 * each remaining entry
1761 					 * has too small (not enough)
1762 					 * scope, because ifa entries
1763 					 * are sorted by their scope
1764 					 * values.
1765 					 */
1766 					goto out;
1767 				}
1768 				break;
1769 			} else if (minihiscore < miniscore) {
1770 				swap(hiscore, score);
1771 				hiscore_idx = 1 - hiscore_idx;
1772 
1773 				/* restore our iterator */
1774 				score->ifa = hiscore->ifa;
1775 
1776 				break;
1777 			}
1778 		}
1779 	}
1780 out:
1781 	return hiscore_idx;
1782 }
1783 
1784 static int ipv6_get_saddr_master(struct net *net,
1785 				 const struct net_device *dst_dev,
1786 				 const struct net_device *master,
1787 				 struct ipv6_saddr_dst *dst,
1788 				 struct ipv6_saddr_score *scores,
1789 				 int hiscore_idx)
1790 {
1791 	struct inet6_dev *idev;
1792 
1793 	idev = __in6_dev_get(dst_dev);
1794 	if (idev)
1795 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1796 						   scores, hiscore_idx);
1797 
1798 	idev = __in6_dev_get(master);
1799 	if (idev)
1800 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1801 						   scores, hiscore_idx);
1802 
1803 	return hiscore_idx;
1804 }
1805 
1806 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1807 		       const struct in6_addr *daddr, unsigned int prefs,
1808 		       struct in6_addr *saddr)
1809 {
1810 	struct ipv6_saddr_score scores[2], *hiscore;
1811 	struct ipv6_saddr_dst dst;
1812 	struct inet6_dev *idev;
1813 	struct net_device *dev;
1814 	int dst_type;
1815 	bool use_oif_addr = false;
1816 	int hiscore_idx = 0;
1817 	int ret = 0;
1818 
1819 	dst_type = __ipv6_addr_type(daddr);
1820 	dst.addr = daddr;
1821 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1822 	dst.scope = __ipv6_addr_src_scope(dst_type);
1823 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1824 	dst.prefs = prefs;
1825 
1826 	scores[hiscore_idx].rule = -1;
1827 	scores[hiscore_idx].ifa = NULL;
1828 
1829 	rcu_read_lock();
1830 
1831 	/* Candidate Source Address (section 4)
1832 	 *  - multicast and link-local destination address,
1833 	 *    the set of candidate source address MUST only
1834 	 *    include addresses assigned to interfaces
1835 	 *    belonging to the same link as the outgoing
1836 	 *    interface.
1837 	 * (- For site-local destination addresses, the
1838 	 *    set of candidate source addresses MUST only
1839 	 *    include addresses assigned to interfaces
1840 	 *    belonging to the same site as the outgoing
1841 	 *    interface.)
1842 	 *  - "It is RECOMMENDED that the candidate source addresses
1843 	 *    be the set of unicast addresses assigned to the
1844 	 *    interface that will be used to send to the destination
1845 	 *    (the 'outgoing' interface)." (RFC 6724)
1846 	 */
1847 	if (dst_dev) {
1848 		idev = __in6_dev_get(dst_dev);
1849 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1850 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1851 		    (idev && READ_ONCE(idev->cnf.use_oif_addrs_only))) {
1852 			use_oif_addr = true;
1853 		}
1854 	}
1855 
1856 	if (use_oif_addr) {
1857 		if (idev)
1858 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1859 	} else {
1860 		const struct net_device *master;
1861 		int master_idx = 0;
1862 
1863 		/* if dst_dev exists and is enslaved to an L3 device, then
1864 		 * prefer addresses from dst_dev and then the master over
1865 		 * any other enslaved devices in the L3 domain.
1866 		 */
1867 		master = l3mdev_master_dev_rcu(dst_dev);
1868 		if (master) {
1869 			master_idx = master->ifindex;
1870 
1871 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1872 							    master, &dst,
1873 							    scores, hiscore_idx);
1874 
1875 			if (scores[hiscore_idx].ifa)
1876 				goto out;
1877 		}
1878 
1879 		for_each_netdev_rcu(net, dev) {
1880 			/* only consider addresses on devices in the
1881 			 * same L3 domain
1882 			 */
1883 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1884 				continue;
1885 			idev = __in6_dev_get(dev);
1886 			if (!idev)
1887 				continue;
1888 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1889 		}
1890 	}
1891 
1892 out:
1893 	hiscore = &scores[hiscore_idx];
1894 	if (!hiscore->ifa)
1895 		ret = -EADDRNOTAVAIL;
1896 	else
1897 		*saddr = hiscore->ifa->addr;
1898 
1899 	rcu_read_unlock();
1900 	return ret;
1901 }
1902 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1903 
1904 static int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1905 			      u32 banned_flags)
1906 {
1907 	struct inet6_ifaddr *ifp;
1908 	int err = -EADDRNOTAVAIL;
1909 
1910 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1911 		if (ifp->scope > IFA_LINK)
1912 			break;
1913 		if (ifp->scope == IFA_LINK &&
1914 		    !(ifp->flags & banned_flags)) {
1915 			*addr = ifp->addr;
1916 			err = 0;
1917 			break;
1918 		}
1919 	}
1920 	return err;
1921 }
1922 
1923 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1924 		    u32 banned_flags)
1925 {
1926 	struct inet6_dev *idev;
1927 	int err = -EADDRNOTAVAIL;
1928 
1929 	rcu_read_lock();
1930 	idev = __in6_dev_get(dev);
1931 	if (idev) {
1932 		read_lock_bh(&idev->lock);
1933 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1934 		read_unlock_bh(&idev->lock);
1935 	}
1936 	rcu_read_unlock();
1937 	return err;
1938 }
1939 
1940 static int ipv6_count_addresses(const struct inet6_dev *idev)
1941 {
1942 	const struct inet6_ifaddr *ifp;
1943 	int cnt = 0;
1944 
1945 	rcu_read_lock();
1946 	list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1947 		cnt++;
1948 	rcu_read_unlock();
1949 	return cnt;
1950 }
1951 
1952 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1953 		  const struct net_device *dev, int strict)
1954 {
1955 	return ipv6_chk_addr_and_flags(net, addr, dev, !dev,
1956 				       strict, IFA_F_TENTATIVE);
1957 }
1958 EXPORT_SYMBOL(ipv6_chk_addr);
1959 
1960 /* device argument is used to find the L3 domain of interest. If
1961  * skip_dev_check is set, then the ifp device is not checked against
1962  * the passed in dev argument. So the 2 cases for addresses checks are:
1963  *   1. does the address exist in the L3 domain that dev is part of
1964  *      (skip_dev_check = true), or
1965  *
1966  *   2. does the address exist on the specific device
1967  *      (skip_dev_check = false)
1968  */
1969 static struct net_device *
1970 __ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1971 			  const struct net_device *dev, bool skip_dev_check,
1972 			  int strict, u32 banned_flags)
1973 {
1974 	unsigned int hash = inet6_addr_hash(net, addr);
1975 	struct net_device *l3mdev, *ndev;
1976 	struct inet6_ifaddr *ifp;
1977 	u32 ifp_flags;
1978 
1979 	rcu_read_lock();
1980 
1981 	l3mdev = l3mdev_master_dev_rcu(dev);
1982 	if (skip_dev_check)
1983 		dev = NULL;
1984 
1985 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
1986 		ndev = ifp->idev->dev;
1987 
1988 		if (l3mdev_master_dev_rcu(ndev) != l3mdev)
1989 			continue;
1990 
1991 		/* Decouple optimistic from tentative for evaluation here.
1992 		 * Ban optimistic addresses explicitly, when required.
1993 		 */
1994 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1995 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1996 			    : ifp->flags;
1997 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1998 		    !(ifp_flags&banned_flags) &&
1999 		    (!dev || ndev == dev ||
2000 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
2001 			rcu_read_unlock();
2002 			return ndev;
2003 		}
2004 	}
2005 
2006 	rcu_read_unlock();
2007 	return NULL;
2008 }
2009 
2010 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
2011 			    const struct net_device *dev, bool skip_dev_check,
2012 			    int strict, u32 banned_flags)
2013 {
2014 	return __ipv6_chk_addr_and_flags(net, addr, dev, skip_dev_check,
2015 					 strict, banned_flags) ? 1 : 0;
2016 }
2017 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
2018 
2019 
2020 /* Compares an address/prefix_len with addresses on device @dev.
2021  * If one is found it returns true.
2022  */
2023 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
2024 	const unsigned int prefix_len, struct net_device *dev)
2025 {
2026 	const struct inet6_ifaddr *ifa;
2027 	const struct inet6_dev *idev;
2028 	bool ret = false;
2029 
2030 	rcu_read_lock();
2031 	idev = __in6_dev_get(dev);
2032 	if (idev) {
2033 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
2034 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
2035 			if (ret)
2036 				break;
2037 		}
2038 	}
2039 	rcu_read_unlock();
2040 
2041 	return ret;
2042 }
2043 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
2044 
2045 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
2046 {
2047 	const struct inet6_ifaddr *ifa;
2048 	const struct inet6_dev *idev;
2049 	int	onlink;
2050 
2051 	onlink = 0;
2052 	rcu_read_lock();
2053 	idev = __in6_dev_get(dev);
2054 	if (idev) {
2055 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
2056 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
2057 						   ifa->prefix_len);
2058 			if (onlink)
2059 				break;
2060 		}
2061 	}
2062 	rcu_read_unlock();
2063 	return onlink;
2064 }
2065 EXPORT_SYMBOL(ipv6_chk_prefix);
2066 
2067 /**
2068  * ipv6_dev_find - find the first device with a given source address.
2069  * @net: the net namespace
2070  * @addr: the source address
2071  * @dev: used to find the L3 domain of interest
2072  *
2073  * The caller should be protected by RCU, or RTNL.
2074  */
2075 struct net_device *ipv6_dev_find(struct net *net, const struct in6_addr *addr,
2076 				 struct net_device *dev)
2077 {
2078 	return __ipv6_chk_addr_and_flags(net, addr, dev, !dev, 1,
2079 					 IFA_F_TENTATIVE);
2080 }
2081 EXPORT_SYMBOL(ipv6_dev_find);
2082 
2083 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
2084 				     struct net_device *dev, int strict)
2085 {
2086 	unsigned int hash = inet6_addr_hash(net, addr);
2087 	struct inet6_ifaddr *ifp, *result = NULL;
2088 
2089 	rcu_read_lock();
2090 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
2091 		if (ipv6_addr_equal(&ifp->addr, addr)) {
2092 			if (!dev || ifp->idev->dev == dev ||
2093 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
2094 				if (in6_ifa_hold_safe(ifp)) {
2095 					result = ifp;
2096 					break;
2097 				}
2098 			}
2099 		}
2100 	}
2101 	rcu_read_unlock();
2102 
2103 	return result;
2104 }
2105 
2106 /* Gets referenced address, destroys ifaddr */
2107 
2108 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
2109 {
2110 	if (dad_failed)
2111 		ifp->flags |= IFA_F_DADFAILED;
2112 
2113 	if (ifp->flags&IFA_F_TEMPORARY) {
2114 		struct inet6_ifaddr *ifpub;
2115 		spin_lock_bh(&ifp->lock);
2116 		ifpub = ifp->ifpub;
2117 		if (ifpub) {
2118 			in6_ifa_hold(ifpub);
2119 			spin_unlock_bh(&ifp->lock);
2120 			ipv6_create_tempaddr(ifpub, true);
2121 			in6_ifa_put(ifpub);
2122 		} else {
2123 			spin_unlock_bh(&ifp->lock);
2124 		}
2125 		ipv6_del_addr(ifp);
2126 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
2127 		spin_lock_bh(&ifp->lock);
2128 		addrconf_del_dad_work(ifp);
2129 		ifp->flags |= IFA_F_TENTATIVE;
2130 		if (dad_failed)
2131 			ifp->flags &= ~IFA_F_OPTIMISTIC;
2132 		spin_unlock_bh(&ifp->lock);
2133 		if (dad_failed)
2134 			ipv6_ifa_notify(0, ifp);
2135 		in6_ifa_put(ifp);
2136 	} else {
2137 		ipv6_del_addr(ifp);
2138 	}
2139 }
2140 
2141 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
2142 {
2143 	int err = -ENOENT;
2144 
2145 	spin_lock_bh(&ifp->lock);
2146 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
2147 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
2148 		err = 0;
2149 	}
2150 	spin_unlock_bh(&ifp->lock);
2151 
2152 	return err;
2153 }
2154 
2155 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp)
2156 {
2157 	struct inet6_dev *idev = ifp->idev;
2158 	struct net *net = dev_net(idev->dev);
2159 	int max_addresses;
2160 
2161 	if (addrconf_dad_end(ifp)) {
2162 		in6_ifa_put(ifp);
2163 		return;
2164 	}
2165 
2166 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c used by %pM detected!\n",
2167 			     ifp->idev->dev->name, &ifp->addr, eth_hdr(skb)->h_source);
2168 
2169 	spin_lock_bh(&ifp->lock);
2170 
2171 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2172 		struct in6_addr new_addr;
2173 		struct inet6_ifaddr *ifp2;
2174 		int retries = ifp->stable_privacy_retry + 1;
2175 		struct ifa6_config cfg = {
2176 			.pfx = &new_addr,
2177 			.plen = ifp->prefix_len,
2178 			.ifa_flags = ifp->flags,
2179 			.valid_lft = ifp->valid_lft,
2180 			.preferred_lft = ifp->prefered_lft,
2181 			.scope = ifp->scope,
2182 		};
2183 
2184 		if (retries > net->ipv6.sysctl.idgen_retries) {
2185 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2186 					     ifp->idev->dev->name);
2187 			goto errdad;
2188 		}
2189 
2190 		new_addr = ifp->addr;
2191 		if (ipv6_generate_stable_address(&new_addr, retries,
2192 						 idev))
2193 			goto errdad;
2194 
2195 		spin_unlock_bh(&ifp->lock);
2196 
2197 		max_addresses = READ_ONCE(idev->cnf.max_addresses);
2198 		if (max_addresses &&
2199 		    ipv6_count_addresses(idev) >= max_addresses)
2200 			goto lock_errdad;
2201 
2202 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2203 				     ifp->idev->dev->name);
2204 
2205 		ifp2 = ipv6_add_addr(idev, &cfg, false, NULL);
2206 		if (IS_ERR(ifp2))
2207 			goto lock_errdad;
2208 
2209 		spin_lock_bh(&ifp2->lock);
2210 		ifp2->stable_privacy_retry = retries;
2211 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2212 		spin_unlock_bh(&ifp2->lock);
2213 
2214 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2215 		in6_ifa_put(ifp2);
2216 lock_errdad:
2217 		spin_lock_bh(&ifp->lock);
2218 	}
2219 
2220 errdad:
2221 	/* transition from _POSTDAD to _ERRDAD */
2222 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2223 	spin_unlock_bh(&ifp->lock);
2224 
2225 	addrconf_mod_dad_work(ifp, 0);
2226 	in6_ifa_put(ifp);
2227 }
2228 
2229 /* Join to solicited addr multicast group.
2230  * caller must hold RTNL */
2231 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2232 {
2233 	struct in6_addr maddr;
2234 
2235 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2236 		return;
2237 
2238 	addrconf_addr_solict_mult(addr, &maddr);
2239 	ipv6_dev_mc_inc(dev, &maddr);
2240 }
2241 
2242 /* caller must hold RTNL */
2243 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2244 {
2245 	struct in6_addr maddr;
2246 
2247 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2248 		return;
2249 
2250 	addrconf_addr_solict_mult(addr, &maddr);
2251 	__ipv6_dev_mc_dec(idev, &maddr);
2252 }
2253 
2254 /* caller must hold RTNL */
2255 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2256 {
2257 	struct in6_addr addr;
2258 
2259 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2260 		return;
2261 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2262 	if (ipv6_addr_any(&addr))
2263 		return;
2264 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2265 }
2266 
2267 /* caller must hold RTNL */
2268 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2269 {
2270 	struct in6_addr addr;
2271 
2272 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2273 		return;
2274 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2275 	if (ipv6_addr_any(&addr))
2276 		return;
2277 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2278 }
2279 
2280 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2281 {
2282 	switch (dev->addr_len) {
2283 	case ETH_ALEN:
2284 		memcpy(eui, dev->dev_addr, 3);
2285 		eui[3] = 0xFF;
2286 		eui[4] = 0xFE;
2287 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2288 		break;
2289 	case EUI64_ADDR_LEN:
2290 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2291 		eui[0] ^= 2;
2292 		break;
2293 	default:
2294 		return -1;
2295 	}
2296 
2297 	return 0;
2298 }
2299 
2300 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2301 {
2302 	const union fwnet_hwaddr *ha;
2303 
2304 	if (dev->addr_len != FWNET_ALEN)
2305 		return -1;
2306 
2307 	ha = (const union fwnet_hwaddr *)dev->dev_addr;
2308 
2309 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2310 	eui[0] ^= 2;
2311 	return 0;
2312 }
2313 
2314 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2315 {
2316 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2317 	if (dev->addr_len != ARCNET_ALEN)
2318 		return -1;
2319 	memset(eui, 0, 7);
2320 	eui[7] = *(u8 *)dev->dev_addr;
2321 	return 0;
2322 }
2323 
2324 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2325 {
2326 	if (dev->addr_len != INFINIBAND_ALEN)
2327 		return -1;
2328 	memcpy(eui, dev->dev_addr + 12, 8);
2329 	eui[0] |= 2;
2330 	return 0;
2331 }
2332 
2333 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2334 {
2335 	if (addr == 0)
2336 		return -1;
2337 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2338 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2339 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2340 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2341 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2342 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2343 	eui[1] = 0;
2344 	eui[2] = 0x5E;
2345 	eui[3] = 0xFE;
2346 	memcpy(eui + 4, &addr, 4);
2347 	return 0;
2348 }
2349 
2350 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2351 {
2352 	if (dev->priv_flags & IFF_ISATAP)
2353 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2354 	return -1;
2355 }
2356 
2357 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2358 {
2359 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2360 }
2361 
2362 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2363 {
2364 	memcpy(eui, dev->perm_addr, 3);
2365 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2366 	eui[3] = 0xFF;
2367 	eui[4] = 0xFE;
2368 	eui[0] ^= 2;
2369 	return 0;
2370 }
2371 
2372 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2373 {
2374 	switch (dev->type) {
2375 	case ARPHRD_ETHER:
2376 	case ARPHRD_FDDI:
2377 		return addrconf_ifid_eui48(eui, dev);
2378 	case ARPHRD_ARCNET:
2379 		return addrconf_ifid_arcnet(eui, dev);
2380 	case ARPHRD_INFINIBAND:
2381 		return addrconf_ifid_infiniband(eui, dev);
2382 	case ARPHRD_SIT:
2383 		return addrconf_ifid_sit(eui, dev);
2384 	case ARPHRD_IPGRE:
2385 	case ARPHRD_TUNNEL:
2386 		return addrconf_ifid_gre(eui, dev);
2387 	case ARPHRD_6LOWPAN:
2388 		return addrconf_ifid_6lowpan(eui, dev);
2389 	case ARPHRD_IEEE1394:
2390 		return addrconf_ifid_ieee1394(eui, dev);
2391 	case ARPHRD_TUNNEL6:
2392 	case ARPHRD_IP6GRE:
2393 	case ARPHRD_RAWIP:
2394 		return addrconf_ifid_ip6tnl(eui, dev);
2395 	}
2396 	return -1;
2397 }
2398 
2399 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2400 {
2401 	int err = -1;
2402 	struct inet6_ifaddr *ifp;
2403 
2404 	read_lock_bh(&idev->lock);
2405 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2406 		if (ifp->scope > IFA_LINK)
2407 			break;
2408 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2409 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2410 			err = 0;
2411 			break;
2412 		}
2413 	}
2414 	read_unlock_bh(&idev->lock);
2415 	return err;
2416 }
2417 
2418 /* Generation of a randomized Interface Identifier
2419  * draft-ietf-6man-rfc4941bis, Section 3.3.1
2420  */
2421 
2422 static void ipv6_gen_rnd_iid(struct in6_addr *addr)
2423 {
2424 regen:
2425 	get_random_bytes(&addr->s6_addr[8], 8);
2426 
2427 	/* <draft-ietf-6man-rfc4941bis-08.txt>, Section 3.3.1:
2428 	 * check if generated address is not inappropriate:
2429 	 *
2430 	 * - Reserved IPv6 Interface Identifiers
2431 	 * - XXX: already assigned to an address on the device
2432 	 */
2433 
2434 	/* Subnet-router anycast: 0000:0000:0000:0000 */
2435 	if (!(addr->s6_addr32[2] | addr->s6_addr32[3]))
2436 		goto regen;
2437 
2438 	/* IANA Ethernet block: 0200:5EFF:FE00:0000-0200:5EFF:FE00:5212
2439 	 * Proxy Mobile IPv6:   0200:5EFF:FE00:5213
2440 	 * IANA Ethernet block: 0200:5EFF:FE00:5214-0200:5EFF:FEFF:FFFF
2441 	 */
2442 	if (ntohl(addr->s6_addr32[2]) == 0x02005eff &&
2443 	    (ntohl(addr->s6_addr32[3]) & 0Xff000000) == 0xfe000000)
2444 		goto regen;
2445 
2446 	/* Reserved subnet anycast addresses */
2447 	if (ntohl(addr->s6_addr32[2]) == 0xfdffffff &&
2448 	    ntohl(addr->s6_addr32[3]) >= 0Xffffff80)
2449 		goto regen;
2450 }
2451 
2452 /*
2453  *	Add prefix route.
2454  */
2455 
2456 static void
2457 addrconf_prefix_route(struct in6_addr *pfx, int plen, u32 metric,
2458 		      struct net_device *dev, unsigned long expires,
2459 		      u32 flags, gfp_t gfp_flags)
2460 {
2461 	struct fib6_config cfg = {
2462 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2463 		.fc_metric = metric ? : IP6_RT_PRIO_ADDRCONF,
2464 		.fc_ifindex = dev->ifindex,
2465 		.fc_expires = expires,
2466 		.fc_dst_len = plen,
2467 		.fc_flags = RTF_UP | flags,
2468 		.fc_nlinfo.nl_net = dev_net(dev),
2469 		.fc_protocol = RTPROT_KERNEL,
2470 		.fc_type = RTN_UNICAST,
2471 	};
2472 
2473 	cfg.fc_dst = *pfx;
2474 
2475 	/* Prevent useless cloning on PtP SIT.
2476 	   This thing is done here expecting that the whole
2477 	   class of non-broadcast devices need not cloning.
2478 	 */
2479 #if IS_ENABLED(CONFIG_IPV6_SIT)
2480 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2481 		cfg.fc_flags |= RTF_NONEXTHOP;
2482 #endif
2483 
2484 	ip6_route_add(&cfg, gfp_flags, NULL);
2485 }
2486 
2487 
2488 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2489 						  int plen,
2490 						  const struct net_device *dev,
2491 						  u32 flags, u32 noflags,
2492 						  bool no_gw)
2493 {
2494 	struct fib6_node *fn;
2495 	struct fib6_info *rt = NULL;
2496 	struct fib6_table *table;
2497 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2498 
2499 	table = fib6_get_table(dev_net(dev), tb_id);
2500 	if (!table)
2501 		return NULL;
2502 
2503 	rcu_read_lock();
2504 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2505 	if (!fn)
2506 		goto out;
2507 
2508 	for_each_fib6_node_rt_rcu(fn) {
2509 		/* prefix routes only use builtin fib6_nh */
2510 		if (rt->nh)
2511 			continue;
2512 
2513 		if (rt->fib6_nh->fib_nh_dev->ifindex != dev->ifindex)
2514 			continue;
2515 		if (no_gw && rt->fib6_nh->fib_nh_gw_family)
2516 			continue;
2517 		if ((rt->fib6_flags & flags) != flags)
2518 			continue;
2519 		if ((rt->fib6_flags & noflags) != 0)
2520 			continue;
2521 		if (!fib6_info_hold_safe(rt))
2522 			continue;
2523 		break;
2524 	}
2525 out:
2526 	rcu_read_unlock();
2527 	return rt;
2528 }
2529 
2530 
2531 /* Create "default" multicast route to the interface */
2532 
2533 static void addrconf_add_mroute(struct net_device *dev)
2534 {
2535 	struct fib6_config cfg = {
2536 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2537 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2538 		.fc_ifindex = dev->ifindex,
2539 		.fc_dst_len = 8,
2540 		.fc_flags = RTF_UP,
2541 		.fc_type = RTN_MULTICAST,
2542 		.fc_nlinfo.nl_net = dev_net(dev),
2543 		.fc_protocol = RTPROT_KERNEL,
2544 	};
2545 
2546 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2547 
2548 	ip6_route_add(&cfg, GFP_KERNEL, NULL);
2549 }
2550 
2551 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2552 {
2553 	struct inet6_dev *idev;
2554 
2555 	ASSERT_RTNL();
2556 
2557 	idev = ipv6_find_idev(dev);
2558 	if (IS_ERR(idev))
2559 		return idev;
2560 
2561 	if (idev->cnf.disable_ipv6)
2562 		return ERR_PTR(-EACCES);
2563 
2564 	/* Add default multicast route */
2565 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2566 		addrconf_add_mroute(dev);
2567 
2568 	return idev;
2569 }
2570 
2571 static void manage_tempaddrs(struct inet6_dev *idev,
2572 			     struct inet6_ifaddr *ifp,
2573 			     __u32 valid_lft, __u32 prefered_lft,
2574 			     bool create, unsigned long now)
2575 {
2576 	u32 flags;
2577 	struct inet6_ifaddr *ift;
2578 
2579 	read_lock_bh(&idev->lock);
2580 	/* update all temporary addresses in the list */
2581 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2582 		int age, max_valid, max_prefered;
2583 
2584 		if (ifp != ift->ifpub)
2585 			continue;
2586 
2587 		/* RFC 4941 section 3.3:
2588 		 * If a received option will extend the lifetime of a public
2589 		 * address, the lifetimes of temporary addresses should
2590 		 * be extended, subject to the overall constraint that no
2591 		 * temporary addresses should ever remain "valid" or "preferred"
2592 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2593 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2594 		 */
2595 		age = (now - ift->cstamp) / HZ;
2596 		max_valid = READ_ONCE(idev->cnf.temp_valid_lft) - age;
2597 		if (max_valid < 0)
2598 			max_valid = 0;
2599 
2600 		max_prefered = READ_ONCE(idev->cnf.temp_prefered_lft) -
2601 			       idev->desync_factor - age;
2602 		if (max_prefered < 0)
2603 			max_prefered = 0;
2604 
2605 		if (valid_lft > max_valid)
2606 			valid_lft = max_valid;
2607 
2608 		if (prefered_lft > max_prefered)
2609 			prefered_lft = max_prefered;
2610 
2611 		spin_lock(&ift->lock);
2612 		flags = ift->flags;
2613 		ift->valid_lft = valid_lft;
2614 		ift->prefered_lft = prefered_lft;
2615 		ift->tstamp = now;
2616 		if (prefered_lft > 0)
2617 			ift->flags &= ~IFA_F_DEPRECATED;
2618 
2619 		spin_unlock(&ift->lock);
2620 		if (!(flags&IFA_F_TENTATIVE))
2621 			ipv6_ifa_notify(0, ift);
2622 	}
2623 
2624 	/* Also create a temporary address if it's enabled but no temporary
2625 	 * address currently exists.
2626 	 * However, we get called with valid_lft == 0, prefered_lft == 0, create == false
2627 	 * as part of cleanup (ie. deleting the mngtmpaddr).
2628 	 * We don't want that to result in creating a new temporary ip address.
2629 	 */
2630 	if (list_empty(&idev->tempaddr_list) && (valid_lft || prefered_lft))
2631 		create = true;
2632 
2633 	if (create && READ_ONCE(idev->cnf.use_tempaddr) > 0) {
2634 		/* When a new public address is created as described
2635 		 * in [ADDRCONF], also create a new temporary address.
2636 		 */
2637 		read_unlock_bh(&idev->lock);
2638 		ipv6_create_tempaddr(ifp, false);
2639 	} else {
2640 		read_unlock_bh(&idev->lock);
2641 	}
2642 }
2643 
2644 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2645 {
2646 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2647 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2648 }
2649 
2650 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2651 				 const struct prefix_info *pinfo,
2652 				 struct inet6_dev *in6_dev,
2653 				 const struct in6_addr *addr, int addr_type,
2654 				 u32 addr_flags, bool sllao, bool tokenized,
2655 				 __u32 valid_lft, u32 prefered_lft)
2656 {
2657 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2658 	int create = 0, update_lft = 0;
2659 
2660 	if (!ifp && valid_lft) {
2661 		int max_addresses = READ_ONCE(in6_dev->cnf.max_addresses);
2662 		struct ifa6_config cfg = {
2663 			.pfx = addr,
2664 			.plen = pinfo->prefix_len,
2665 			.ifa_flags = addr_flags,
2666 			.valid_lft = valid_lft,
2667 			.preferred_lft = prefered_lft,
2668 			.scope = addr_type & IPV6_ADDR_SCOPE_MASK,
2669 			.ifa_proto = IFAPROT_KERNEL_RA
2670 		};
2671 
2672 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2673 		if ((READ_ONCE(net->ipv6.devconf_all->optimistic_dad) ||
2674 		     READ_ONCE(in6_dev->cnf.optimistic_dad)) &&
2675 		    !net->ipv6.devconf_all->forwarding && sllao)
2676 			cfg.ifa_flags |= IFA_F_OPTIMISTIC;
2677 #endif
2678 
2679 		/* Do not allow to create too much of autoconfigured
2680 		 * addresses; this would be too easy way to crash kernel.
2681 		 */
2682 		if (!max_addresses ||
2683 		    ipv6_count_addresses(in6_dev) < max_addresses)
2684 			ifp = ipv6_add_addr(in6_dev, &cfg, false, NULL);
2685 
2686 		if (IS_ERR_OR_NULL(ifp))
2687 			return -1;
2688 
2689 		create = 1;
2690 		spin_lock_bh(&ifp->lock);
2691 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2692 		ifp->cstamp = jiffies;
2693 		ifp->tokenized = tokenized;
2694 		spin_unlock_bh(&ifp->lock);
2695 		addrconf_dad_start(ifp);
2696 	}
2697 
2698 	if (ifp) {
2699 		u32 flags;
2700 		unsigned long now;
2701 		u32 stored_lft;
2702 
2703 		/* update lifetime (RFC2462 5.5.3 e) */
2704 		spin_lock_bh(&ifp->lock);
2705 		now = jiffies;
2706 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2707 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2708 		else
2709 			stored_lft = 0;
2710 
2711 		/* RFC4862 Section 5.5.3e:
2712 		 * "Note that the preferred lifetime of the
2713 		 *  corresponding address is always reset to
2714 		 *  the Preferred Lifetime in the received
2715 		 *  Prefix Information option, regardless of
2716 		 *  whether the valid lifetime is also reset or
2717 		 *  ignored."
2718 		 *
2719 		 * So we should always update prefered_lft here.
2720 		 */
2721 		update_lft = !create && stored_lft;
2722 
2723 		if (update_lft && !READ_ONCE(in6_dev->cnf.ra_honor_pio_life)) {
2724 			const u32 minimum_lft = min_t(u32,
2725 				stored_lft, MIN_VALID_LIFETIME);
2726 			valid_lft = max(valid_lft, minimum_lft);
2727 		}
2728 
2729 		if (update_lft) {
2730 			ifp->valid_lft = valid_lft;
2731 			ifp->prefered_lft = prefered_lft;
2732 			WRITE_ONCE(ifp->tstamp, now);
2733 			flags = ifp->flags;
2734 			ifp->flags &= ~IFA_F_DEPRECATED;
2735 			spin_unlock_bh(&ifp->lock);
2736 
2737 			if (!(flags&IFA_F_TENTATIVE))
2738 				ipv6_ifa_notify(0, ifp);
2739 		} else
2740 			spin_unlock_bh(&ifp->lock);
2741 
2742 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2743 				 create, now);
2744 
2745 		in6_ifa_put(ifp);
2746 		addrconf_verify(net);
2747 	}
2748 
2749 	return 0;
2750 }
2751 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2752 
2753 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2754 {
2755 	struct prefix_info *pinfo;
2756 	struct fib6_table *table;
2757 	__u32 valid_lft;
2758 	__u32 prefered_lft;
2759 	int addr_type, err;
2760 	u32 addr_flags = 0;
2761 	struct inet6_dev *in6_dev;
2762 	struct net *net = dev_net(dev);
2763 
2764 	pinfo = (struct prefix_info *) opt;
2765 
2766 	if (len < sizeof(struct prefix_info)) {
2767 		netdev_dbg(dev, "addrconf: prefix option too short\n");
2768 		return;
2769 	}
2770 
2771 	/*
2772 	 *	Validation checks ([ADDRCONF], page 19)
2773 	 */
2774 
2775 	addr_type = ipv6_addr_type(&pinfo->prefix);
2776 
2777 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2778 		return;
2779 
2780 	valid_lft = ntohl(pinfo->valid);
2781 	prefered_lft = ntohl(pinfo->prefered);
2782 
2783 	if (prefered_lft > valid_lft) {
2784 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2785 		return;
2786 	}
2787 
2788 	in6_dev = in6_dev_get(dev);
2789 
2790 	if (!in6_dev) {
2791 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2792 				    dev->name);
2793 		return;
2794 	}
2795 
2796 	if (valid_lft != 0 && valid_lft < in6_dev->cnf.accept_ra_min_lft)
2797 		goto put;
2798 
2799 	/*
2800 	 *	Two things going on here:
2801 	 *	1) Add routes for on-link prefixes
2802 	 *	2) Configure prefixes with the auto flag set
2803 	 */
2804 
2805 	if (pinfo->onlink) {
2806 		struct fib6_info *rt;
2807 		unsigned long rt_expires;
2808 
2809 		/* Avoid arithmetic overflow. Really, we could
2810 		 * save rt_expires in seconds, likely valid_lft,
2811 		 * but it would require division in fib gc, that it
2812 		 * not good.
2813 		 */
2814 		if (HZ > USER_HZ)
2815 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2816 		else
2817 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2818 
2819 		if (addrconf_finite_timeout(rt_expires))
2820 			rt_expires *= HZ;
2821 
2822 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2823 					       pinfo->prefix_len,
2824 					       dev,
2825 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2826 					       RTF_DEFAULT, true);
2827 
2828 		if (rt) {
2829 			/* Autoconf prefix route */
2830 			if (valid_lft == 0) {
2831 				ip6_del_rt(net, rt, false);
2832 				rt = NULL;
2833 			} else {
2834 				table = rt->fib6_table;
2835 				spin_lock_bh(&table->tb6_lock);
2836 
2837 				if (addrconf_finite_timeout(rt_expires)) {
2838 					/* not infinity */
2839 					fib6_set_expires(rt, jiffies + rt_expires);
2840 					fib6_add_gc_list(rt);
2841 				} else {
2842 					fib6_clean_expires(rt);
2843 					fib6_remove_gc_list(rt);
2844 				}
2845 
2846 				spin_unlock_bh(&table->tb6_lock);
2847 			}
2848 		} else if (valid_lft) {
2849 			clock_t expires = 0;
2850 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2851 			if (addrconf_finite_timeout(rt_expires)) {
2852 				/* not infinity */
2853 				flags |= RTF_EXPIRES;
2854 				expires = jiffies_to_clock_t(rt_expires);
2855 			}
2856 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2857 					      0, dev, expires, flags,
2858 					      GFP_ATOMIC);
2859 		}
2860 		fib6_info_release(rt);
2861 	}
2862 
2863 	/* Try to figure out our local address for this prefix */
2864 
2865 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2866 		struct in6_addr addr;
2867 		bool tokenized = false, dev_addr_generated = false;
2868 
2869 		if (pinfo->prefix_len == 64) {
2870 			memcpy(&addr, &pinfo->prefix, 8);
2871 
2872 			if (!ipv6_addr_any(&in6_dev->token)) {
2873 				read_lock_bh(&in6_dev->lock);
2874 				memcpy(addr.s6_addr + 8,
2875 				       in6_dev->token.s6_addr + 8, 8);
2876 				read_unlock_bh(&in6_dev->lock);
2877 				tokenized = true;
2878 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2879 				   !ipv6_generate_stable_address(&addr, 0,
2880 								 in6_dev)) {
2881 				addr_flags |= IFA_F_STABLE_PRIVACY;
2882 				goto ok;
2883 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2884 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2885 				goto put;
2886 			} else {
2887 				dev_addr_generated = true;
2888 			}
2889 			goto ok;
2890 		}
2891 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2892 				    pinfo->prefix_len);
2893 		goto put;
2894 
2895 ok:
2896 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2897 						   &addr, addr_type,
2898 						   addr_flags, sllao,
2899 						   tokenized, valid_lft,
2900 						   prefered_lft);
2901 		if (err)
2902 			goto put;
2903 
2904 		/* Ignore error case here because previous prefix add addr was
2905 		 * successful which will be notified.
2906 		 */
2907 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2908 					      addr_type, addr_flags, sllao,
2909 					      tokenized, valid_lft,
2910 					      prefered_lft,
2911 					      dev_addr_generated);
2912 	}
2913 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2914 put:
2915 	in6_dev_put(in6_dev);
2916 }
2917 
2918 static int addrconf_set_sit_dstaddr(struct net *net, struct net_device *dev,
2919 		struct in6_ifreq *ireq)
2920 {
2921 	struct ip_tunnel_parm p = { };
2922 	int err;
2923 
2924 	if (!(ipv6_addr_type(&ireq->ifr6_addr) & IPV6_ADDR_COMPATv4))
2925 		return -EADDRNOTAVAIL;
2926 
2927 	p.iph.daddr = ireq->ifr6_addr.s6_addr32[3];
2928 	p.iph.version = 4;
2929 	p.iph.ihl = 5;
2930 	p.iph.protocol = IPPROTO_IPV6;
2931 	p.iph.ttl = 64;
2932 
2933 	if (!dev->netdev_ops->ndo_tunnel_ctl)
2934 		return -EOPNOTSUPP;
2935 	err = dev->netdev_ops->ndo_tunnel_ctl(dev, &p, SIOCADDTUNNEL);
2936 	if (err)
2937 		return err;
2938 
2939 	dev = __dev_get_by_name(net, p.name);
2940 	if (!dev)
2941 		return -ENOBUFS;
2942 	return dev_open(dev, NULL);
2943 }
2944 
2945 /*
2946  *	Set destination address.
2947  *	Special case for SIT interfaces where we create a new "virtual"
2948  *	device.
2949  */
2950 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2951 {
2952 	struct net_device *dev;
2953 	struct in6_ifreq ireq;
2954 	int err = -ENODEV;
2955 
2956 	if (!IS_ENABLED(CONFIG_IPV6_SIT))
2957 		return -ENODEV;
2958 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2959 		return -EFAULT;
2960 
2961 	rtnl_lock();
2962 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2963 	if (dev && dev->type == ARPHRD_SIT)
2964 		err = addrconf_set_sit_dstaddr(net, dev, &ireq);
2965 	rtnl_unlock();
2966 	return err;
2967 }
2968 
2969 static int ipv6_mc_config(struct sock *sk, bool join,
2970 			  const struct in6_addr *addr, int ifindex)
2971 {
2972 	int ret;
2973 
2974 	ASSERT_RTNL();
2975 
2976 	lock_sock(sk);
2977 	if (join)
2978 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2979 	else
2980 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2981 	release_sock(sk);
2982 
2983 	return ret;
2984 }
2985 
2986 /*
2987  *	Manual configuration of address on an interface
2988  */
2989 static int inet6_addr_add(struct net *net, int ifindex,
2990 			  struct ifa6_config *cfg,
2991 			  struct netlink_ext_ack *extack)
2992 {
2993 	struct inet6_ifaddr *ifp;
2994 	struct inet6_dev *idev;
2995 	struct net_device *dev;
2996 	unsigned long timeout;
2997 	clock_t expires;
2998 	u32 flags;
2999 
3000 	ASSERT_RTNL();
3001 
3002 	if (cfg->plen > 128) {
3003 		NL_SET_ERR_MSG_MOD(extack, "Invalid prefix length");
3004 		return -EINVAL;
3005 	}
3006 
3007 	/* check the lifetime */
3008 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft) {
3009 		NL_SET_ERR_MSG_MOD(extack, "address lifetime invalid");
3010 		return -EINVAL;
3011 	}
3012 
3013 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR && cfg->plen != 64) {
3014 		NL_SET_ERR_MSG_MOD(extack, "address with \"mngtmpaddr\" flag must have a prefix length of 64");
3015 		return -EINVAL;
3016 	}
3017 
3018 	dev = __dev_get_by_index(net, ifindex);
3019 	if (!dev)
3020 		return -ENODEV;
3021 
3022 	idev = addrconf_add_dev(dev);
3023 	if (IS_ERR(idev)) {
3024 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
3025 		return PTR_ERR(idev);
3026 	}
3027 
3028 	if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
3029 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3030 					 true, cfg->pfx, ifindex);
3031 
3032 		if (ret < 0) {
3033 			NL_SET_ERR_MSG_MOD(extack, "Multicast auto join failed");
3034 			return ret;
3035 		}
3036 	}
3037 
3038 	cfg->scope = ipv6_addr_scope(cfg->pfx);
3039 
3040 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
3041 	if (addrconf_finite_timeout(timeout)) {
3042 		expires = jiffies_to_clock_t(timeout * HZ);
3043 		cfg->valid_lft = timeout;
3044 		flags = RTF_EXPIRES;
3045 	} else {
3046 		expires = 0;
3047 		flags = 0;
3048 		cfg->ifa_flags |= IFA_F_PERMANENT;
3049 	}
3050 
3051 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
3052 	if (addrconf_finite_timeout(timeout)) {
3053 		if (timeout == 0)
3054 			cfg->ifa_flags |= IFA_F_DEPRECATED;
3055 		cfg->preferred_lft = timeout;
3056 	}
3057 
3058 	ifp = ipv6_add_addr(idev, cfg, true, extack);
3059 	if (!IS_ERR(ifp)) {
3060 		if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
3061 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3062 					      ifp->rt_priority, dev, expires,
3063 					      flags, GFP_KERNEL);
3064 		}
3065 
3066 		/* Send a netlink notification if DAD is enabled and
3067 		 * optimistic flag is not set
3068 		 */
3069 		if (!(ifp->flags & (IFA_F_OPTIMISTIC | IFA_F_NODAD)))
3070 			ipv6_ifa_notify(0, ifp);
3071 		/*
3072 		 * Note that section 3.1 of RFC 4429 indicates
3073 		 * that the Optimistic flag should not be set for
3074 		 * manually configured addresses
3075 		 */
3076 		addrconf_dad_start(ifp);
3077 		if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR)
3078 			manage_tempaddrs(idev, ifp, cfg->valid_lft,
3079 					 cfg->preferred_lft, true, jiffies);
3080 		in6_ifa_put(ifp);
3081 		addrconf_verify_rtnl(net);
3082 		return 0;
3083 	} else if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
3084 		ipv6_mc_config(net->ipv6.mc_autojoin_sk, false,
3085 			       cfg->pfx, ifindex);
3086 	}
3087 
3088 	return PTR_ERR(ifp);
3089 }
3090 
3091 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
3092 			  const struct in6_addr *pfx, unsigned int plen,
3093 			  struct netlink_ext_ack *extack)
3094 {
3095 	struct inet6_ifaddr *ifp;
3096 	struct inet6_dev *idev;
3097 	struct net_device *dev;
3098 
3099 	if (plen > 128) {
3100 		NL_SET_ERR_MSG_MOD(extack, "Invalid prefix length");
3101 		return -EINVAL;
3102 	}
3103 
3104 	dev = __dev_get_by_index(net, ifindex);
3105 	if (!dev) {
3106 		NL_SET_ERR_MSG_MOD(extack, "Unable to find the interface");
3107 		return -ENODEV;
3108 	}
3109 
3110 	idev = __in6_dev_get(dev);
3111 	if (!idev) {
3112 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
3113 		return -ENXIO;
3114 	}
3115 
3116 	read_lock_bh(&idev->lock);
3117 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3118 		if (ifp->prefix_len == plen &&
3119 		    ipv6_addr_equal(pfx, &ifp->addr)) {
3120 			in6_ifa_hold(ifp);
3121 			read_unlock_bh(&idev->lock);
3122 
3123 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
3124 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
3125 				manage_tempaddrs(idev, ifp, 0, 0, false,
3126 						 jiffies);
3127 			ipv6_del_addr(ifp);
3128 			addrconf_verify_rtnl(net);
3129 			if (ipv6_addr_is_multicast(pfx)) {
3130 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3131 					       false, pfx, dev->ifindex);
3132 			}
3133 			return 0;
3134 		}
3135 	}
3136 	read_unlock_bh(&idev->lock);
3137 
3138 	NL_SET_ERR_MSG_MOD(extack, "address not found");
3139 	return -EADDRNOTAVAIL;
3140 }
3141 
3142 
3143 int addrconf_add_ifaddr(struct net *net, void __user *arg)
3144 {
3145 	struct ifa6_config cfg = {
3146 		.ifa_flags = IFA_F_PERMANENT,
3147 		.preferred_lft = INFINITY_LIFE_TIME,
3148 		.valid_lft = INFINITY_LIFE_TIME,
3149 	};
3150 	struct in6_ifreq ireq;
3151 	int err;
3152 
3153 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3154 		return -EPERM;
3155 
3156 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3157 		return -EFAULT;
3158 
3159 	cfg.pfx = &ireq.ifr6_addr;
3160 	cfg.plen = ireq.ifr6_prefixlen;
3161 
3162 	rtnl_lock();
3163 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &cfg, NULL);
3164 	rtnl_unlock();
3165 	return err;
3166 }
3167 
3168 int addrconf_del_ifaddr(struct net *net, void __user *arg)
3169 {
3170 	struct in6_ifreq ireq;
3171 	int err;
3172 
3173 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3174 		return -EPERM;
3175 
3176 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3177 		return -EFAULT;
3178 
3179 	rtnl_lock();
3180 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
3181 			     ireq.ifr6_prefixlen, NULL);
3182 	rtnl_unlock();
3183 	return err;
3184 }
3185 
3186 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
3187 		     int plen, int scope, u8 proto)
3188 {
3189 	struct inet6_ifaddr *ifp;
3190 	struct ifa6_config cfg = {
3191 		.pfx = addr,
3192 		.plen = plen,
3193 		.ifa_flags = IFA_F_PERMANENT,
3194 		.valid_lft = INFINITY_LIFE_TIME,
3195 		.preferred_lft = INFINITY_LIFE_TIME,
3196 		.scope = scope,
3197 		.ifa_proto = proto
3198 	};
3199 
3200 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3201 	if (!IS_ERR(ifp)) {
3202 		spin_lock_bh(&ifp->lock);
3203 		ifp->flags &= ~IFA_F_TENTATIVE;
3204 		spin_unlock_bh(&ifp->lock);
3205 		rt_genid_bump_ipv6(dev_net(idev->dev));
3206 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3207 		in6_ifa_put(ifp);
3208 	}
3209 }
3210 
3211 #if IS_ENABLED(CONFIG_IPV6_SIT) || IS_ENABLED(CONFIG_NET_IPGRE) || IS_ENABLED(CONFIG_IPV6_GRE)
3212 static void add_v4_addrs(struct inet6_dev *idev)
3213 {
3214 	struct in6_addr addr;
3215 	struct net_device *dev;
3216 	struct net *net = dev_net(idev->dev);
3217 	int scope, plen, offset = 0;
3218 	u32 pflags = 0;
3219 
3220 	ASSERT_RTNL();
3221 
3222 	memset(&addr, 0, sizeof(struct in6_addr));
3223 	/* in case of IP6GRE the dev_addr is an IPv6 and therefore we use only the last 4 bytes */
3224 	if (idev->dev->addr_len == sizeof(struct in6_addr))
3225 		offset = sizeof(struct in6_addr) - 4;
3226 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr + offset, 4);
3227 
3228 	if (!(idev->dev->flags & IFF_POINTOPOINT) && idev->dev->type == ARPHRD_SIT) {
3229 		scope = IPV6_ADDR_COMPATv4;
3230 		plen = 96;
3231 		pflags |= RTF_NONEXTHOP;
3232 	} else {
3233 		if (idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_NONE)
3234 			return;
3235 
3236 		addr.s6_addr32[0] = htonl(0xfe800000);
3237 		scope = IFA_LINK;
3238 		plen = 64;
3239 	}
3240 
3241 	if (addr.s6_addr32[3]) {
3242 		add_addr(idev, &addr, plen, scope, IFAPROT_UNSPEC);
3243 		addrconf_prefix_route(&addr, plen, 0, idev->dev, 0, pflags,
3244 				      GFP_KERNEL);
3245 		return;
3246 	}
3247 
3248 	for_each_netdev(net, dev) {
3249 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3250 		if (in_dev && (dev->flags & IFF_UP)) {
3251 			struct in_ifaddr *ifa;
3252 			int flag = scope;
3253 
3254 			in_dev_for_each_ifa_rtnl(ifa, in_dev) {
3255 				addr.s6_addr32[3] = ifa->ifa_local;
3256 
3257 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3258 					continue;
3259 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3260 					if (idev->dev->flags&IFF_POINTOPOINT)
3261 						continue;
3262 					flag |= IFA_HOST;
3263 				}
3264 
3265 				add_addr(idev, &addr, plen, flag,
3266 					 IFAPROT_UNSPEC);
3267 				addrconf_prefix_route(&addr, plen, 0, idev->dev,
3268 						      0, pflags, GFP_KERNEL);
3269 			}
3270 		}
3271 	}
3272 }
3273 #endif
3274 
3275 static void init_loopback(struct net_device *dev)
3276 {
3277 	struct inet6_dev  *idev;
3278 
3279 	/* ::1 */
3280 
3281 	ASSERT_RTNL();
3282 
3283 	idev = ipv6_find_idev(dev);
3284 	if (IS_ERR(idev)) {
3285 		pr_debug("%s: add_dev failed\n", __func__);
3286 		return;
3287 	}
3288 
3289 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST, IFAPROT_KERNEL_LO);
3290 }
3291 
3292 void addrconf_add_linklocal(struct inet6_dev *idev,
3293 			    const struct in6_addr *addr, u32 flags)
3294 {
3295 	struct ifa6_config cfg = {
3296 		.pfx = addr,
3297 		.plen = 64,
3298 		.ifa_flags = flags | IFA_F_PERMANENT,
3299 		.valid_lft = INFINITY_LIFE_TIME,
3300 		.preferred_lft = INFINITY_LIFE_TIME,
3301 		.scope = IFA_LINK,
3302 		.ifa_proto = IFAPROT_KERNEL_LL
3303 	};
3304 	struct inet6_ifaddr *ifp;
3305 
3306 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3307 	if ((READ_ONCE(dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad) ||
3308 	     READ_ONCE(idev->cnf.optimistic_dad)) &&
3309 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3310 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
3311 #endif
3312 
3313 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3314 	if (!IS_ERR(ifp)) {
3315 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, 0, idev->dev,
3316 				      0, 0, GFP_ATOMIC);
3317 		addrconf_dad_start(ifp);
3318 		in6_ifa_put(ifp);
3319 	}
3320 }
3321 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3322 
3323 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3324 {
3325 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3326 		return true;
3327 
3328 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3329 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3330 		return true;
3331 
3332 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3333 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3334 		return true;
3335 
3336 	return false;
3337 }
3338 
3339 static int ipv6_generate_stable_address(struct in6_addr *address,
3340 					u8 dad_count,
3341 					const struct inet6_dev *idev)
3342 {
3343 	static DEFINE_SPINLOCK(lock);
3344 	static __u32 digest[SHA1_DIGEST_WORDS];
3345 	static __u32 workspace[SHA1_WORKSPACE_WORDS];
3346 
3347 	static union {
3348 		char __data[SHA1_BLOCK_SIZE];
3349 		struct {
3350 			struct in6_addr secret;
3351 			__be32 prefix[2];
3352 			unsigned char hwaddr[MAX_ADDR_LEN];
3353 			u8 dad_count;
3354 		} __packed;
3355 	} data;
3356 
3357 	struct in6_addr secret;
3358 	struct in6_addr temp;
3359 	struct net *net = dev_net(idev->dev);
3360 
3361 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3362 
3363 	if (idev->cnf.stable_secret.initialized)
3364 		secret = idev->cnf.stable_secret.secret;
3365 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3366 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3367 	else
3368 		return -1;
3369 
3370 retry:
3371 	spin_lock_bh(&lock);
3372 
3373 	sha1_init(digest);
3374 	memset(&data, 0, sizeof(data));
3375 	memset(workspace, 0, sizeof(workspace));
3376 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3377 	data.prefix[0] = address->s6_addr32[0];
3378 	data.prefix[1] = address->s6_addr32[1];
3379 	data.secret = secret;
3380 	data.dad_count = dad_count;
3381 
3382 	sha1_transform(digest, data.__data, workspace);
3383 
3384 	temp = *address;
3385 	temp.s6_addr32[2] = (__force __be32)digest[0];
3386 	temp.s6_addr32[3] = (__force __be32)digest[1];
3387 
3388 	spin_unlock_bh(&lock);
3389 
3390 	if (ipv6_reserved_interfaceid(temp)) {
3391 		dad_count++;
3392 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3393 			return -1;
3394 		goto retry;
3395 	}
3396 
3397 	*address = temp;
3398 	return 0;
3399 }
3400 
3401 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3402 {
3403 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3404 
3405 	if (s->initialized)
3406 		return;
3407 	s = &idev->cnf.stable_secret;
3408 	get_random_bytes(&s->secret, sizeof(s->secret));
3409 	s->initialized = true;
3410 }
3411 
3412 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3413 {
3414 	struct in6_addr addr;
3415 
3416 	/* no link local addresses on L3 master devices */
3417 	if (netif_is_l3_master(idev->dev))
3418 		return;
3419 
3420 	/* no link local addresses on devices flagged as slaves */
3421 	if (idev->dev->priv_flags & IFF_NO_ADDRCONF)
3422 		return;
3423 
3424 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3425 
3426 	switch (idev->cnf.addr_gen_mode) {
3427 	case IN6_ADDR_GEN_MODE_RANDOM:
3428 		ipv6_gen_mode_random_init(idev);
3429 		fallthrough;
3430 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3431 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3432 			addrconf_add_linklocal(idev, &addr,
3433 					       IFA_F_STABLE_PRIVACY);
3434 		else if (prefix_route)
3435 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3436 					      0, 0, GFP_KERNEL);
3437 		break;
3438 	case IN6_ADDR_GEN_MODE_EUI64:
3439 		/* addrconf_add_linklocal also adds a prefix_route and we
3440 		 * only need to care about prefix routes if ipv6_generate_eui64
3441 		 * couldn't generate one.
3442 		 */
3443 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3444 			addrconf_add_linklocal(idev, &addr, 0);
3445 		else if (prefix_route)
3446 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3447 					      0, 0, GFP_KERNEL);
3448 		break;
3449 	case IN6_ADDR_GEN_MODE_NONE:
3450 	default:
3451 		/* will not add any link local address */
3452 		break;
3453 	}
3454 }
3455 
3456 static void addrconf_dev_config(struct net_device *dev)
3457 {
3458 	struct inet6_dev *idev;
3459 
3460 	ASSERT_RTNL();
3461 
3462 	if ((dev->type != ARPHRD_ETHER) &&
3463 	    (dev->type != ARPHRD_FDDI) &&
3464 	    (dev->type != ARPHRD_ARCNET) &&
3465 	    (dev->type != ARPHRD_INFINIBAND) &&
3466 	    (dev->type != ARPHRD_IEEE1394) &&
3467 	    (dev->type != ARPHRD_TUNNEL6) &&
3468 	    (dev->type != ARPHRD_6LOWPAN) &&
3469 	    (dev->type != ARPHRD_TUNNEL) &&
3470 	    (dev->type != ARPHRD_NONE) &&
3471 	    (dev->type != ARPHRD_RAWIP)) {
3472 		/* Alas, we support only Ethernet autoconfiguration. */
3473 		idev = __in6_dev_get(dev);
3474 		if (!IS_ERR_OR_NULL(idev) && dev->flags & IFF_UP &&
3475 		    dev->flags & IFF_MULTICAST)
3476 			ipv6_mc_up(idev);
3477 		return;
3478 	}
3479 
3480 	idev = addrconf_add_dev(dev);
3481 	if (IS_ERR(idev))
3482 		return;
3483 
3484 	/* this device type has no EUI support */
3485 	if (dev->type == ARPHRD_NONE &&
3486 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3487 		WRITE_ONCE(idev->cnf.addr_gen_mode,
3488 			   IN6_ADDR_GEN_MODE_RANDOM);
3489 
3490 	addrconf_addr_gen(idev, false);
3491 }
3492 
3493 #if IS_ENABLED(CONFIG_IPV6_SIT)
3494 static void addrconf_sit_config(struct net_device *dev)
3495 {
3496 	struct inet6_dev *idev;
3497 
3498 	ASSERT_RTNL();
3499 
3500 	/*
3501 	 * Configure the tunnel with one of our IPv4
3502 	 * addresses... we should configure all of
3503 	 * our v4 addrs in the tunnel
3504 	 */
3505 
3506 	idev = ipv6_find_idev(dev);
3507 	if (IS_ERR(idev)) {
3508 		pr_debug("%s: add_dev failed\n", __func__);
3509 		return;
3510 	}
3511 
3512 	if (dev->priv_flags & IFF_ISATAP) {
3513 		addrconf_addr_gen(idev, false);
3514 		return;
3515 	}
3516 
3517 	add_v4_addrs(idev);
3518 
3519 	if (dev->flags&IFF_POINTOPOINT)
3520 		addrconf_add_mroute(dev);
3521 }
3522 #endif
3523 
3524 #if IS_ENABLED(CONFIG_NET_IPGRE) || IS_ENABLED(CONFIG_IPV6_GRE)
3525 static void addrconf_gre_config(struct net_device *dev)
3526 {
3527 	struct inet6_dev *idev;
3528 
3529 	ASSERT_RTNL();
3530 
3531 	idev = ipv6_find_idev(dev);
3532 	if (IS_ERR(idev)) {
3533 		pr_debug("%s: add_dev failed\n", __func__);
3534 		return;
3535 	}
3536 
3537 	if (dev->type == ARPHRD_ETHER) {
3538 		addrconf_addr_gen(idev, true);
3539 		return;
3540 	}
3541 
3542 	add_v4_addrs(idev);
3543 
3544 	if (dev->flags & IFF_POINTOPOINT)
3545 		addrconf_add_mroute(dev);
3546 }
3547 #endif
3548 
3549 static void addrconf_init_auto_addrs(struct net_device *dev)
3550 {
3551 	switch (dev->type) {
3552 #if IS_ENABLED(CONFIG_IPV6_SIT)
3553 	case ARPHRD_SIT:
3554 		addrconf_sit_config(dev);
3555 		break;
3556 #endif
3557 #if IS_ENABLED(CONFIG_NET_IPGRE) || IS_ENABLED(CONFIG_IPV6_GRE)
3558 	case ARPHRD_IP6GRE:
3559 	case ARPHRD_IPGRE:
3560 		addrconf_gre_config(dev);
3561 		break;
3562 #endif
3563 	case ARPHRD_LOOPBACK:
3564 		init_loopback(dev);
3565 		break;
3566 
3567 	default:
3568 		addrconf_dev_config(dev);
3569 		break;
3570 	}
3571 }
3572 
3573 static int fixup_permanent_addr(struct net *net,
3574 				struct inet6_dev *idev,
3575 				struct inet6_ifaddr *ifp)
3576 {
3577 	/* !fib6_node means the host route was removed from the
3578 	 * FIB, for example, if 'lo' device is taken down. In that
3579 	 * case regenerate the host route.
3580 	 */
3581 	if (!ifp->rt || !ifp->rt->fib6_node) {
3582 		struct fib6_info *f6i, *prev;
3583 
3584 		f6i = addrconf_f6i_alloc(net, idev, &ifp->addr, false,
3585 					 GFP_ATOMIC, NULL);
3586 		if (IS_ERR(f6i))
3587 			return PTR_ERR(f6i);
3588 
3589 		/* ifp->rt can be accessed outside of rtnl */
3590 		spin_lock(&ifp->lock);
3591 		prev = ifp->rt;
3592 		ifp->rt = f6i;
3593 		spin_unlock(&ifp->lock);
3594 
3595 		fib6_info_release(prev);
3596 	}
3597 
3598 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3599 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3600 				      ifp->rt_priority, idev->dev, 0, 0,
3601 				      GFP_ATOMIC);
3602 	}
3603 
3604 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3605 		addrconf_dad_start(ifp);
3606 
3607 	return 0;
3608 }
3609 
3610 static void addrconf_permanent_addr(struct net *net, struct net_device *dev)
3611 {
3612 	struct inet6_ifaddr *ifp, *tmp;
3613 	struct inet6_dev *idev;
3614 
3615 	idev = __in6_dev_get(dev);
3616 	if (!idev)
3617 		return;
3618 
3619 	write_lock_bh(&idev->lock);
3620 
3621 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3622 		if ((ifp->flags & IFA_F_PERMANENT) &&
3623 		    fixup_permanent_addr(net, idev, ifp) < 0) {
3624 			write_unlock_bh(&idev->lock);
3625 			in6_ifa_hold(ifp);
3626 			ipv6_del_addr(ifp);
3627 			write_lock_bh(&idev->lock);
3628 
3629 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3630 					     idev->dev->name, &ifp->addr);
3631 		}
3632 	}
3633 
3634 	write_unlock_bh(&idev->lock);
3635 }
3636 
3637 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3638 			   void *ptr)
3639 {
3640 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3641 	struct netdev_notifier_change_info *change_info;
3642 	struct netdev_notifier_changeupper_info *info;
3643 	struct inet6_dev *idev = __in6_dev_get(dev);
3644 	struct net *net = dev_net(dev);
3645 	int run_pending = 0;
3646 	int err;
3647 
3648 	switch (event) {
3649 	case NETDEV_REGISTER:
3650 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3651 			idev = ipv6_add_dev(dev);
3652 			if (IS_ERR(idev))
3653 				return notifier_from_errno(PTR_ERR(idev));
3654 		}
3655 		break;
3656 
3657 	case NETDEV_CHANGEMTU:
3658 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3659 		if (dev->mtu < IPV6_MIN_MTU) {
3660 			addrconf_ifdown(dev, dev != net->loopback_dev);
3661 			break;
3662 		}
3663 
3664 		if (idev) {
3665 			rt6_mtu_change(dev, dev->mtu);
3666 			WRITE_ONCE(idev->cnf.mtu6, dev->mtu);
3667 			break;
3668 		}
3669 
3670 		/* allocate new idev */
3671 		idev = ipv6_add_dev(dev);
3672 		if (IS_ERR(idev))
3673 			break;
3674 
3675 		/* device is still not ready */
3676 		if (!(idev->if_flags & IF_READY))
3677 			break;
3678 
3679 		run_pending = 1;
3680 		fallthrough;
3681 	case NETDEV_UP:
3682 	case NETDEV_CHANGE:
3683 		if (idev && idev->cnf.disable_ipv6)
3684 			break;
3685 
3686 		if (dev->priv_flags & IFF_NO_ADDRCONF) {
3687 			if (event == NETDEV_UP && !IS_ERR_OR_NULL(idev) &&
3688 			    dev->flags & IFF_UP && dev->flags & IFF_MULTICAST)
3689 				ipv6_mc_up(idev);
3690 			break;
3691 		}
3692 
3693 		if (event == NETDEV_UP) {
3694 			/* restore routes for permanent addresses */
3695 			addrconf_permanent_addr(net, dev);
3696 
3697 			if (!addrconf_link_ready(dev)) {
3698 				/* device is not ready yet. */
3699 				pr_debug("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3700 					 dev->name);
3701 				break;
3702 			}
3703 
3704 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3705 				idev = ipv6_add_dev(dev);
3706 
3707 			if (!IS_ERR_OR_NULL(idev)) {
3708 				idev->if_flags |= IF_READY;
3709 				run_pending = 1;
3710 			}
3711 		} else if (event == NETDEV_CHANGE) {
3712 			if (!addrconf_link_ready(dev)) {
3713 				/* device is still not ready. */
3714 				rt6_sync_down_dev(dev, event);
3715 				break;
3716 			}
3717 
3718 			if (!IS_ERR_OR_NULL(idev)) {
3719 				if (idev->if_flags & IF_READY) {
3720 					/* device is already configured -
3721 					 * but resend MLD reports, we might
3722 					 * have roamed and need to update
3723 					 * multicast snooping switches
3724 					 */
3725 					ipv6_mc_up(idev);
3726 					change_info = ptr;
3727 					if (change_info->flags_changed & IFF_NOARP)
3728 						addrconf_dad_run(idev, true);
3729 					rt6_sync_up(dev, RTNH_F_LINKDOWN);
3730 					break;
3731 				}
3732 				idev->if_flags |= IF_READY;
3733 			}
3734 
3735 			pr_debug("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3736 				 dev->name);
3737 
3738 			run_pending = 1;
3739 		}
3740 
3741 		addrconf_init_auto_addrs(dev);
3742 
3743 		if (!IS_ERR_OR_NULL(idev)) {
3744 			if (run_pending)
3745 				addrconf_dad_run(idev, false);
3746 
3747 			/* Device has an address by now */
3748 			rt6_sync_up(dev, RTNH_F_DEAD);
3749 
3750 			/*
3751 			 * If the MTU changed during the interface down,
3752 			 * when the interface up, the changed MTU must be
3753 			 * reflected in the idev as well as routers.
3754 			 */
3755 			if (idev->cnf.mtu6 != dev->mtu &&
3756 			    dev->mtu >= IPV6_MIN_MTU) {
3757 				rt6_mtu_change(dev, dev->mtu);
3758 				WRITE_ONCE(idev->cnf.mtu6, dev->mtu);
3759 			}
3760 			WRITE_ONCE(idev->tstamp, jiffies);
3761 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3762 
3763 			/*
3764 			 * If the changed mtu during down is lower than
3765 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3766 			 */
3767 			if (dev->mtu < IPV6_MIN_MTU)
3768 				addrconf_ifdown(dev, dev != net->loopback_dev);
3769 		}
3770 		break;
3771 
3772 	case NETDEV_DOWN:
3773 	case NETDEV_UNREGISTER:
3774 		/*
3775 		 *	Remove all addresses from this interface.
3776 		 */
3777 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3778 		break;
3779 
3780 	case NETDEV_CHANGENAME:
3781 		if (idev) {
3782 			snmp6_unregister_dev(idev);
3783 			addrconf_sysctl_unregister(idev);
3784 			err = addrconf_sysctl_register(idev);
3785 			if (err)
3786 				return notifier_from_errno(err);
3787 			err = snmp6_register_dev(idev);
3788 			if (err) {
3789 				addrconf_sysctl_unregister(idev);
3790 				return notifier_from_errno(err);
3791 			}
3792 		}
3793 		break;
3794 
3795 	case NETDEV_PRE_TYPE_CHANGE:
3796 	case NETDEV_POST_TYPE_CHANGE:
3797 		if (idev)
3798 			addrconf_type_change(dev, event);
3799 		break;
3800 
3801 	case NETDEV_CHANGEUPPER:
3802 		info = ptr;
3803 
3804 		/* flush all routes if dev is linked to or unlinked from
3805 		 * an L3 master device (e.g., VRF)
3806 		 */
3807 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3808 			addrconf_ifdown(dev, false);
3809 	}
3810 
3811 	return NOTIFY_OK;
3812 }
3813 
3814 /*
3815  *	addrconf module should be notified of a device going up
3816  */
3817 static struct notifier_block ipv6_dev_notf = {
3818 	.notifier_call = addrconf_notify,
3819 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3820 };
3821 
3822 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3823 {
3824 	struct inet6_dev *idev;
3825 	ASSERT_RTNL();
3826 
3827 	idev = __in6_dev_get(dev);
3828 
3829 	if (event == NETDEV_POST_TYPE_CHANGE)
3830 		ipv6_mc_remap(idev);
3831 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3832 		ipv6_mc_unmap(idev);
3833 }
3834 
3835 static bool addr_is_local(const struct in6_addr *addr)
3836 {
3837 	return ipv6_addr_type(addr) &
3838 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3839 }
3840 
3841 static int addrconf_ifdown(struct net_device *dev, bool unregister)
3842 {
3843 	unsigned long event = unregister ? NETDEV_UNREGISTER : NETDEV_DOWN;
3844 	struct net *net = dev_net(dev);
3845 	struct inet6_dev *idev;
3846 	struct inet6_ifaddr *ifa;
3847 	LIST_HEAD(tmp_addr_list);
3848 	bool keep_addr = false;
3849 	bool was_ready;
3850 	int state, i;
3851 
3852 	ASSERT_RTNL();
3853 
3854 	rt6_disable_ip(dev, event);
3855 
3856 	idev = __in6_dev_get(dev);
3857 	if (!idev)
3858 		return -ENODEV;
3859 
3860 	/*
3861 	 * Step 1: remove reference to ipv6 device from parent device.
3862 	 *	   Do not dev_put!
3863 	 */
3864 	if (unregister) {
3865 		idev->dead = 1;
3866 
3867 		/* protected by rtnl_lock */
3868 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3869 
3870 		/* Step 1.5: remove snmp6 entry */
3871 		snmp6_unregister_dev(idev);
3872 
3873 	}
3874 
3875 	/* combine the user config with event to determine if permanent
3876 	 * addresses are to be removed from address hash table
3877 	 */
3878 	if (!unregister && !idev->cnf.disable_ipv6) {
3879 		/* aggregate the system setting and interface setting */
3880 		int _keep_addr = READ_ONCE(net->ipv6.devconf_all->keep_addr_on_down);
3881 
3882 		if (!_keep_addr)
3883 			_keep_addr = READ_ONCE(idev->cnf.keep_addr_on_down);
3884 
3885 		keep_addr = (_keep_addr > 0);
3886 	}
3887 
3888 	/* Step 2: clear hash table */
3889 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3890 		struct hlist_head *h = &net->ipv6.inet6_addr_lst[i];
3891 
3892 		spin_lock_bh(&net->ipv6.addrconf_hash_lock);
3893 restart:
3894 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3895 			if (ifa->idev == idev) {
3896 				addrconf_del_dad_work(ifa);
3897 				/* combined flag + permanent flag decide if
3898 				 * address is retained on a down event
3899 				 */
3900 				if (!keep_addr ||
3901 				    !(ifa->flags & IFA_F_PERMANENT) ||
3902 				    addr_is_local(&ifa->addr)) {
3903 					hlist_del_init_rcu(&ifa->addr_lst);
3904 					goto restart;
3905 				}
3906 			}
3907 		}
3908 		spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
3909 	}
3910 
3911 	write_lock_bh(&idev->lock);
3912 
3913 	addrconf_del_rs_timer(idev);
3914 
3915 	/* Step 2: clear flags for stateless addrconf, repeated down
3916 	 *         detection
3917 	 */
3918 	was_ready = idev->if_flags & IF_READY;
3919 	if (!unregister)
3920 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3921 
3922 	/* Step 3: clear tempaddr list */
3923 	while (!list_empty(&idev->tempaddr_list)) {
3924 		ifa = list_first_entry(&idev->tempaddr_list,
3925 				       struct inet6_ifaddr, tmp_list);
3926 		list_del(&ifa->tmp_list);
3927 		write_unlock_bh(&idev->lock);
3928 		spin_lock_bh(&ifa->lock);
3929 
3930 		if (ifa->ifpub) {
3931 			in6_ifa_put(ifa->ifpub);
3932 			ifa->ifpub = NULL;
3933 		}
3934 		spin_unlock_bh(&ifa->lock);
3935 		in6_ifa_put(ifa);
3936 		write_lock_bh(&idev->lock);
3937 	}
3938 
3939 	list_for_each_entry(ifa, &idev->addr_list, if_list)
3940 		list_add_tail(&ifa->if_list_aux, &tmp_addr_list);
3941 	write_unlock_bh(&idev->lock);
3942 
3943 	while (!list_empty(&tmp_addr_list)) {
3944 		struct fib6_info *rt = NULL;
3945 		bool keep;
3946 
3947 		ifa = list_first_entry(&tmp_addr_list,
3948 				       struct inet6_ifaddr, if_list_aux);
3949 		list_del(&ifa->if_list_aux);
3950 
3951 		addrconf_del_dad_work(ifa);
3952 
3953 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3954 			!addr_is_local(&ifa->addr);
3955 
3956 		spin_lock_bh(&ifa->lock);
3957 
3958 		if (keep) {
3959 			/* set state to skip the notifier below */
3960 			state = INET6_IFADDR_STATE_DEAD;
3961 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3962 			if (!(ifa->flags & IFA_F_NODAD))
3963 				ifa->flags |= IFA_F_TENTATIVE;
3964 
3965 			rt = ifa->rt;
3966 			ifa->rt = NULL;
3967 		} else {
3968 			state = ifa->state;
3969 			ifa->state = INET6_IFADDR_STATE_DEAD;
3970 		}
3971 
3972 		spin_unlock_bh(&ifa->lock);
3973 
3974 		if (rt)
3975 			ip6_del_rt(net, rt, false);
3976 
3977 		if (state != INET6_IFADDR_STATE_DEAD) {
3978 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3979 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3980 		} else {
3981 			if (idev->cnf.forwarding)
3982 				addrconf_leave_anycast(ifa);
3983 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3984 		}
3985 
3986 		if (!keep) {
3987 			write_lock_bh(&idev->lock);
3988 			list_del_rcu(&ifa->if_list);
3989 			write_unlock_bh(&idev->lock);
3990 			in6_ifa_put(ifa);
3991 		}
3992 	}
3993 
3994 	/* Step 5: Discard anycast and multicast list */
3995 	if (unregister) {
3996 		ipv6_ac_destroy_dev(idev);
3997 		ipv6_mc_destroy_dev(idev);
3998 	} else if (was_ready) {
3999 		ipv6_mc_down(idev);
4000 	}
4001 
4002 	WRITE_ONCE(idev->tstamp, jiffies);
4003 	idev->ra_mtu = 0;
4004 
4005 	/* Last: Shot the device (if unregistered) */
4006 	if (unregister) {
4007 		addrconf_sysctl_unregister(idev);
4008 		neigh_parms_release(&nd_tbl, idev->nd_parms);
4009 		neigh_ifdown(&nd_tbl, dev);
4010 		in6_dev_put(idev);
4011 	}
4012 	return 0;
4013 }
4014 
4015 static void addrconf_rs_timer(struct timer_list *t)
4016 {
4017 	struct inet6_dev *idev = from_timer(idev, t, rs_timer);
4018 	struct net_device *dev = idev->dev;
4019 	struct in6_addr lladdr;
4020 	int rtr_solicits;
4021 
4022 	write_lock(&idev->lock);
4023 	if (idev->dead || !(idev->if_flags & IF_READY))
4024 		goto out;
4025 
4026 	if (!ipv6_accept_ra(idev))
4027 		goto out;
4028 
4029 	/* Announcement received after solicitation was sent */
4030 	if (idev->if_flags & IF_RA_RCVD)
4031 		goto out;
4032 
4033 	rtr_solicits = READ_ONCE(idev->cnf.rtr_solicits);
4034 
4035 	if (idev->rs_probes++ < rtr_solicits || rtr_solicits < 0) {
4036 		write_unlock(&idev->lock);
4037 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4038 			ndisc_send_rs(dev, &lladdr,
4039 				      &in6addr_linklocal_allrouters);
4040 		else
4041 			goto put;
4042 
4043 		write_lock(&idev->lock);
4044 		idev->rs_interval = rfc3315_s14_backoff_update(
4045 				idev->rs_interval,
4046 				READ_ONCE(idev->cnf.rtr_solicit_max_interval));
4047 		/* The wait after the last probe can be shorter */
4048 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
4049 					     READ_ONCE(idev->cnf.rtr_solicits)) ?
4050 				      READ_ONCE(idev->cnf.rtr_solicit_delay) :
4051 				      idev->rs_interval);
4052 	} else {
4053 		/*
4054 		 * Note: we do not support deprecated "all on-link"
4055 		 * assumption any longer.
4056 		 */
4057 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
4058 	}
4059 
4060 out:
4061 	write_unlock(&idev->lock);
4062 put:
4063 	in6_dev_put(idev);
4064 }
4065 
4066 /*
4067  *	Duplicate Address Detection
4068  */
4069 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
4070 {
4071 	struct inet6_dev *idev = ifp->idev;
4072 	unsigned long rand_num;
4073 	u64 nonce;
4074 
4075 	if (ifp->flags & IFA_F_OPTIMISTIC)
4076 		rand_num = 0;
4077 	else
4078 		rand_num = get_random_u32_below(
4079 				READ_ONCE(idev->cnf.rtr_solicit_delay) ? : 1);
4080 
4081 	nonce = 0;
4082 	if (READ_ONCE(idev->cnf.enhanced_dad) ||
4083 	    READ_ONCE(dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad)) {
4084 		do
4085 			get_random_bytes(&nonce, 6);
4086 		while (nonce == 0);
4087 	}
4088 	ifp->dad_nonce = nonce;
4089 	ifp->dad_probes = READ_ONCE(idev->cnf.dad_transmits);
4090 	addrconf_mod_dad_work(ifp, rand_num);
4091 }
4092 
4093 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
4094 {
4095 	struct inet6_dev *idev = ifp->idev;
4096 	struct net_device *dev = idev->dev;
4097 	bool bump_id, notify = false;
4098 	struct net *net;
4099 
4100 	addrconf_join_solict(dev, &ifp->addr);
4101 
4102 	read_lock_bh(&idev->lock);
4103 	spin_lock(&ifp->lock);
4104 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
4105 		goto out;
4106 
4107 	net = dev_net(dev);
4108 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
4109 	    (READ_ONCE(net->ipv6.devconf_all->accept_dad) < 1 &&
4110 	     READ_ONCE(idev->cnf.accept_dad) < 1) ||
4111 	    !(ifp->flags&IFA_F_TENTATIVE) ||
4112 	    ifp->flags & IFA_F_NODAD) {
4113 		bool send_na = false;
4114 
4115 		if (ifp->flags & IFA_F_TENTATIVE &&
4116 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4117 			send_na = true;
4118 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4119 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4120 		spin_unlock(&ifp->lock);
4121 		read_unlock_bh(&idev->lock);
4122 
4123 		addrconf_dad_completed(ifp, bump_id, send_na);
4124 		return;
4125 	}
4126 
4127 	if (!(idev->if_flags & IF_READY)) {
4128 		spin_unlock(&ifp->lock);
4129 		read_unlock_bh(&idev->lock);
4130 		/*
4131 		 * If the device is not ready:
4132 		 * - keep it tentative if it is a permanent address.
4133 		 * - otherwise, kill it.
4134 		 */
4135 		in6_ifa_hold(ifp);
4136 		addrconf_dad_stop(ifp, 0);
4137 		return;
4138 	}
4139 
4140 	/*
4141 	 * Optimistic nodes can start receiving
4142 	 * Frames right away
4143 	 */
4144 	if (ifp->flags & IFA_F_OPTIMISTIC) {
4145 		ip6_ins_rt(net, ifp->rt);
4146 		if (ipv6_use_optimistic_addr(net, idev)) {
4147 			/* Because optimistic nodes can use this address,
4148 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
4149 			 */
4150 			notify = true;
4151 		}
4152 	}
4153 
4154 	addrconf_dad_kick(ifp);
4155 out:
4156 	spin_unlock(&ifp->lock);
4157 	read_unlock_bh(&idev->lock);
4158 	if (notify)
4159 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
4160 }
4161 
4162 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
4163 {
4164 	bool begin_dad = false;
4165 
4166 	spin_lock_bh(&ifp->lock);
4167 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
4168 		ifp->state = INET6_IFADDR_STATE_PREDAD;
4169 		begin_dad = true;
4170 	}
4171 	spin_unlock_bh(&ifp->lock);
4172 
4173 	if (begin_dad)
4174 		addrconf_mod_dad_work(ifp, 0);
4175 }
4176 
4177 static void addrconf_dad_work(struct work_struct *w)
4178 {
4179 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
4180 						struct inet6_ifaddr,
4181 						dad_work);
4182 	struct inet6_dev *idev = ifp->idev;
4183 	bool bump_id, disable_ipv6 = false;
4184 	struct in6_addr mcaddr;
4185 
4186 	enum {
4187 		DAD_PROCESS,
4188 		DAD_BEGIN,
4189 		DAD_ABORT,
4190 	} action = DAD_PROCESS;
4191 
4192 	rtnl_lock();
4193 
4194 	spin_lock_bh(&ifp->lock);
4195 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
4196 		action = DAD_BEGIN;
4197 		ifp->state = INET6_IFADDR_STATE_DAD;
4198 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
4199 		action = DAD_ABORT;
4200 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
4201 
4202 		if ((READ_ONCE(dev_net(idev->dev)->ipv6.devconf_all->accept_dad) > 1 ||
4203 		     READ_ONCE(idev->cnf.accept_dad) > 1) &&
4204 		    !idev->cnf.disable_ipv6 &&
4205 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
4206 			struct in6_addr addr;
4207 
4208 			addr.s6_addr32[0] = htonl(0xfe800000);
4209 			addr.s6_addr32[1] = 0;
4210 
4211 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
4212 			    ipv6_addr_equal(&ifp->addr, &addr)) {
4213 				/* DAD failed for link-local based on MAC */
4214 				WRITE_ONCE(idev->cnf.disable_ipv6, 1);
4215 
4216 				pr_info("%s: IPv6 being disabled!\n",
4217 					ifp->idev->dev->name);
4218 				disable_ipv6 = true;
4219 			}
4220 		}
4221 	}
4222 	spin_unlock_bh(&ifp->lock);
4223 
4224 	if (action == DAD_BEGIN) {
4225 		addrconf_dad_begin(ifp);
4226 		goto out;
4227 	} else if (action == DAD_ABORT) {
4228 		in6_ifa_hold(ifp);
4229 		addrconf_dad_stop(ifp, 1);
4230 		if (disable_ipv6)
4231 			addrconf_ifdown(idev->dev, false);
4232 		goto out;
4233 	}
4234 
4235 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
4236 		goto out;
4237 
4238 	write_lock_bh(&idev->lock);
4239 	if (idev->dead || !(idev->if_flags & IF_READY)) {
4240 		write_unlock_bh(&idev->lock);
4241 		goto out;
4242 	}
4243 
4244 	spin_lock(&ifp->lock);
4245 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
4246 		spin_unlock(&ifp->lock);
4247 		write_unlock_bh(&idev->lock);
4248 		goto out;
4249 	}
4250 
4251 	if (ifp->dad_probes == 0) {
4252 		bool send_na = false;
4253 
4254 		/*
4255 		 * DAD was successful
4256 		 */
4257 
4258 		if (ifp->flags & IFA_F_TENTATIVE &&
4259 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4260 			send_na = true;
4261 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4262 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4263 		spin_unlock(&ifp->lock);
4264 		write_unlock_bh(&idev->lock);
4265 
4266 		addrconf_dad_completed(ifp, bump_id, send_na);
4267 
4268 		goto out;
4269 	}
4270 
4271 	ifp->dad_probes--;
4272 	addrconf_mod_dad_work(ifp,
4273 			      max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME),
4274 				  HZ/100));
4275 	spin_unlock(&ifp->lock);
4276 	write_unlock_bh(&idev->lock);
4277 
4278 	/* send a neighbour solicitation for our addr */
4279 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4280 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4281 		      ifp->dad_nonce);
4282 out:
4283 	in6_ifa_put(ifp);
4284 	rtnl_unlock();
4285 }
4286 
4287 /* ifp->idev must be at least read locked */
4288 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4289 {
4290 	struct inet6_ifaddr *ifpiter;
4291 	struct inet6_dev *idev = ifp->idev;
4292 
4293 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4294 		if (ifpiter->scope > IFA_LINK)
4295 			break;
4296 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4297 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4298 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4299 		    IFA_F_PERMANENT)
4300 			return false;
4301 	}
4302 	return true;
4303 }
4304 
4305 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
4306 				   bool send_na)
4307 {
4308 	struct net_device *dev = ifp->idev->dev;
4309 	struct in6_addr lladdr;
4310 	bool send_rs, send_mld;
4311 
4312 	addrconf_del_dad_work(ifp);
4313 
4314 	/*
4315 	 *	Configure the address for reception. Now it is valid.
4316 	 */
4317 
4318 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4319 
4320 	/* If added prefix is link local and we are prepared to process
4321 	   router advertisements, start sending router solicitations.
4322 	 */
4323 
4324 	read_lock_bh(&ifp->idev->lock);
4325 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4326 	send_rs = send_mld &&
4327 		  ipv6_accept_ra(ifp->idev) &&
4328 		  READ_ONCE(ifp->idev->cnf.rtr_solicits) != 0 &&
4329 		  (dev->flags & IFF_LOOPBACK) == 0 &&
4330 		  (dev->type != ARPHRD_TUNNEL) &&
4331 		  !netif_is_team_port(dev);
4332 	read_unlock_bh(&ifp->idev->lock);
4333 
4334 	/* While dad is in progress mld report's source address is in6_addrany.
4335 	 * Resend with proper ll now.
4336 	 */
4337 	if (send_mld)
4338 		ipv6_mc_dad_complete(ifp->idev);
4339 
4340 	/* send unsolicited NA if enabled */
4341 	if (send_na &&
4342 	    (READ_ONCE(ifp->idev->cnf.ndisc_notify) ||
4343 	     READ_ONCE(dev_net(dev)->ipv6.devconf_all->ndisc_notify))) {
4344 		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifp->addr,
4345 			      /*router=*/ !!ifp->idev->cnf.forwarding,
4346 			      /*solicited=*/ false, /*override=*/ true,
4347 			      /*inc_opt=*/ true);
4348 	}
4349 
4350 	if (send_rs) {
4351 		/*
4352 		 *	If a host as already performed a random delay
4353 		 *	[...] as part of DAD [...] there is no need
4354 		 *	to delay again before sending the first RS
4355 		 */
4356 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4357 			return;
4358 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4359 
4360 		write_lock_bh(&ifp->idev->lock);
4361 		spin_lock(&ifp->lock);
4362 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4363 			READ_ONCE(ifp->idev->cnf.rtr_solicit_interval));
4364 		ifp->idev->rs_probes = 1;
4365 		ifp->idev->if_flags |= IF_RS_SENT;
4366 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4367 		spin_unlock(&ifp->lock);
4368 		write_unlock_bh(&ifp->idev->lock);
4369 	}
4370 
4371 	if (bump_id)
4372 		rt_genid_bump_ipv6(dev_net(dev));
4373 
4374 	/* Make sure that a new temporary address will be created
4375 	 * before this temporary address becomes deprecated.
4376 	 */
4377 	if (ifp->flags & IFA_F_TEMPORARY)
4378 		addrconf_verify_rtnl(dev_net(dev));
4379 }
4380 
4381 static void addrconf_dad_run(struct inet6_dev *idev, bool restart)
4382 {
4383 	struct inet6_ifaddr *ifp;
4384 
4385 	read_lock_bh(&idev->lock);
4386 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4387 		spin_lock(&ifp->lock);
4388 		if ((ifp->flags & IFA_F_TENTATIVE &&
4389 		     ifp->state == INET6_IFADDR_STATE_DAD) || restart) {
4390 			if (restart)
4391 				ifp->state = INET6_IFADDR_STATE_PREDAD;
4392 			addrconf_dad_kick(ifp);
4393 		}
4394 		spin_unlock(&ifp->lock);
4395 	}
4396 	read_unlock_bh(&idev->lock);
4397 }
4398 
4399 #ifdef CONFIG_PROC_FS
4400 struct if6_iter_state {
4401 	struct seq_net_private p;
4402 	int bucket;
4403 	int offset;
4404 };
4405 
4406 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4407 {
4408 	struct if6_iter_state *state = seq->private;
4409 	struct net *net = seq_file_net(seq);
4410 	struct inet6_ifaddr *ifa = NULL;
4411 	int p = 0;
4412 
4413 	/* initial bucket if pos is 0 */
4414 	if (pos == 0) {
4415 		state->bucket = 0;
4416 		state->offset = 0;
4417 	}
4418 
4419 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4420 		hlist_for_each_entry_rcu(ifa, &net->ipv6.inet6_addr_lst[state->bucket],
4421 					 addr_lst) {
4422 			/* sync with offset */
4423 			if (p < state->offset) {
4424 				p++;
4425 				continue;
4426 			}
4427 			return ifa;
4428 		}
4429 
4430 		/* prepare for next bucket */
4431 		state->offset = 0;
4432 		p = 0;
4433 	}
4434 	return NULL;
4435 }
4436 
4437 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4438 					 struct inet6_ifaddr *ifa)
4439 {
4440 	struct if6_iter_state *state = seq->private;
4441 	struct net *net = seq_file_net(seq);
4442 
4443 	hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4444 		state->offset++;
4445 		return ifa;
4446 	}
4447 
4448 	state->offset = 0;
4449 	while (++state->bucket < IN6_ADDR_HSIZE) {
4450 		hlist_for_each_entry_rcu(ifa,
4451 				     &net->ipv6.inet6_addr_lst[state->bucket], addr_lst) {
4452 			return ifa;
4453 		}
4454 	}
4455 
4456 	return NULL;
4457 }
4458 
4459 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4460 	__acquires(rcu)
4461 {
4462 	rcu_read_lock();
4463 	return if6_get_first(seq, *pos);
4464 }
4465 
4466 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4467 {
4468 	struct inet6_ifaddr *ifa;
4469 
4470 	ifa = if6_get_next(seq, v);
4471 	++*pos;
4472 	return ifa;
4473 }
4474 
4475 static void if6_seq_stop(struct seq_file *seq, void *v)
4476 	__releases(rcu)
4477 {
4478 	rcu_read_unlock();
4479 }
4480 
4481 static int if6_seq_show(struct seq_file *seq, void *v)
4482 {
4483 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4484 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4485 		   &ifp->addr,
4486 		   ifp->idev->dev->ifindex,
4487 		   ifp->prefix_len,
4488 		   ifp->scope,
4489 		   (u8) ifp->flags,
4490 		   ifp->idev->dev->name);
4491 	return 0;
4492 }
4493 
4494 static const struct seq_operations if6_seq_ops = {
4495 	.start	= if6_seq_start,
4496 	.next	= if6_seq_next,
4497 	.show	= if6_seq_show,
4498 	.stop	= if6_seq_stop,
4499 };
4500 
4501 static int __net_init if6_proc_net_init(struct net *net)
4502 {
4503 	if (!proc_create_net("if_inet6", 0444, net->proc_net, &if6_seq_ops,
4504 			sizeof(struct if6_iter_state)))
4505 		return -ENOMEM;
4506 	return 0;
4507 }
4508 
4509 static void __net_exit if6_proc_net_exit(struct net *net)
4510 {
4511 	remove_proc_entry("if_inet6", net->proc_net);
4512 }
4513 
4514 static struct pernet_operations if6_proc_net_ops = {
4515 	.init = if6_proc_net_init,
4516 	.exit = if6_proc_net_exit,
4517 };
4518 
4519 int __init if6_proc_init(void)
4520 {
4521 	return register_pernet_subsys(&if6_proc_net_ops);
4522 }
4523 
4524 void if6_proc_exit(void)
4525 {
4526 	unregister_pernet_subsys(&if6_proc_net_ops);
4527 }
4528 #endif	/* CONFIG_PROC_FS */
4529 
4530 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4531 /* Check if address is a home address configured on any interface. */
4532 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4533 {
4534 	unsigned int hash = inet6_addr_hash(net, addr);
4535 	struct inet6_ifaddr *ifp = NULL;
4536 	int ret = 0;
4537 
4538 	rcu_read_lock();
4539 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
4540 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4541 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4542 			ret = 1;
4543 			break;
4544 		}
4545 	}
4546 	rcu_read_unlock();
4547 	return ret;
4548 }
4549 #endif
4550 
4551 /* RFC6554 has some algorithm to avoid loops in segment routing by
4552  * checking if the segments contains any of a local interface address.
4553  *
4554  * Quote:
4555  *
4556  * To detect loops in the SRH, a router MUST determine if the SRH
4557  * includes multiple addresses assigned to any interface on that router.
4558  * If such addresses appear more than once and are separated by at least
4559  * one address not assigned to that router.
4560  */
4561 int ipv6_chk_rpl_srh_loop(struct net *net, const struct in6_addr *segs,
4562 			  unsigned char nsegs)
4563 {
4564 	const struct in6_addr *addr;
4565 	int i, ret = 0, found = 0;
4566 	struct inet6_ifaddr *ifp;
4567 	bool separated = false;
4568 	unsigned int hash;
4569 	bool hash_found;
4570 
4571 	rcu_read_lock();
4572 	for (i = 0; i < nsegs; i++) {
4573 		addr = &segs[i];
4574 		hash = inet6_addr_hash(net, addr);
4575 
4576 		hash_found = false;
4577 		hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
4578 
4579 			if (ipv6_addr_equal(&ifp->addr, addr)) {
4580 				hash_found = true;
4581 				break;
4582 			}
4583 		}
4584 
4585 		if (hash_found) {
4586 			if (found > 1 && separated) {
4587 				ret = 1;
4588 				break;
4589 			}
4590 
4591 			separated = false;
4592 			found++;
4593 		} else {
4594 			separated = true;
4595 		}
4596 	}
4597 	rcu_read_unlock();
4598 
4599 	return ret;
4600 }
4601 
4602 /*
4603  *	Periodic address status verification
4604  */
4605 
4606 static void addrconf_verify_rtnl(struct net *net)
4607 {
4608 	unsigned long now, next, next_sec, next_sched;
4609 	struct inet6_ifaddr *ifp;
4610 	int i;
4611 
4612 	ASSERT_RTNL();
4613 
4614 	rcu_read_lock_bh();
4615 	now = jiffies;
4616 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4617 
4618 	cancel_delayed_work(&net->ipv6.addr_chk_work);
4619 
4620 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4621 restart:
4622 		hlist_for_each_entry_rcu_bh(ifp, &net->ipv6.inet6_addr_lst[i], addr_lst) {
4623 			unsigned long age;
4624 
4625 			/* When setting preferred_lft to a value not zero or
4626 			 * infinity, while valid_lft is infinity
4627 			 * IFA_F_PERMANENT has a non-infinity life time.
4628 			 */
4629 			if ((ifp->flags & IFA_F_PERMANENT) &&
4630 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4631 				continue;
4632 
4633 			spin_lock(&ifp->lock);
4634 			/* We try to batch several events at once. */
4635 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4636 
4637 			if ((ifp->flags&IFA_F_TEMPORARY) &&
4638 			    !(ifp->flags&IFA_F_TENTATIVE) &&
4639 			    ifp->prefered_lft != INFINITY_LIFE_TIME &&
4640 			    !ifp->regen_count && ifp->ifpub) {
4641 				/* This is a non-regenerated temporary addr. */
4642 
4643 				unsigned long regen_advance = ipv6_get_regen_advance(ifp->idev);
4644 
4645 				if (age + regen_advance >= ifp->prefered_lft) {
4646 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4647 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4648 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4649 
4650 					ifp->regen_count++;
4651 					in6_ifa_hold(ifp);
4652 					in6_ifa_hold(ifpub);
4653 					spin_unlock(&ifp->lock);
4654 
4655 					spin_lock(&ifpub->lock);
4656 					ifpub->regen_count = 0;
4657 					spin_unlock(&ifpub->lock);
4658 					rcu_read_unlock_bh();
4659 					ipv6_create_tempaddr(ifpub, true);
4660 					in6_ifa_put(ifpub);
4661 					in6_ifa_put(ifp);
4662 					rcu_read_lock_bh();
4663 					goto restart;
4664 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4665 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4666 			}
4667 
4668 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4669 			    age >= ifp->valid_lft) {
4670 				spin_unlock(&ifp->lock);
4671 				in6_ifa_hold(ifp);
4672 				rcu_read_unlock_bh();
4673 				ipv6_del_addr(ifp);
4674 				rcu_read_lock_bh();
4675 				goto restart;
4676 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4677 				spin_unlock(&ifp->lock);
4678 				continue;
4679 			} else if (age >= ifp->prefered_lft) {
4680 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4681 				int deprecate = 0;
4682 
4683 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4684 					deprecate = 1;
4685 					ifp->flags |= IFA_F_DEPRECATED;
4686 				}
4687 
4688 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4689 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4690 					next = ifp->tstamp + ifp->valid_lft * HZ;
4691 
4692 				spin_unlock(&ifp->lock);
4693 
4694 				if (deprecate) {
4695 					in6_ifa_hold(ifp);
4696 
4697 					ipv6_ifa_notify(0, ifp);
4698 					in6_ifa_put(ifp);
4699 					goto restart;
4700 				}
4701 			} else {
4702 				/* ifp->prefered_lft <= ifp->valid_lft */
4703 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4704 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4705 				spin_unlock(&ifp->lock);
4706 			}
4707 		}
4708 	}
4709 
4710 	next_sec = round_jiffies_up(next);
4711 	next_sched = next;
4712 
4713 	/* If rounded timeout is accurate enough, accept it. */
4714 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4715 		next_sched = next_sec;
4716 
4717 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4718 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4719 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4720 
4721 	pr_debug("now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4722 		 now, next, next_sec, next_sched);
4723 	mod_delayed_work(addrconf_wq, &net->ipv6.addr_chk_work, next_sched - now);
4724 	rcu_read_unlock_bh();
4725 }
4726 
4727 static void addrconf_verify_work(struct work_struct *w)
4728 {
4729 	struct net *net = container_of(to_delayed_work(w), struct net,
4730 				       ipv6.addr_chk_work);
4731 
4732 	rtnl_lock();
4733 	addrconf_verify_rtnl(net);
4734 	rtnl_unlock();
4735 }
4736 
4737 static void addrconf_verify(struct net *net)
4738 {
4739 	mod_delayed_work(addrconf_wq, &net->ipv6.addr_chk_work, 0);
4740 }
4741 
4742 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4743 				     struct in6_addr **peer_pfx)
4744 {
4745 	struct in6_addr *pfx = NULL;
4746 
4747 	*peer_pfx = NULL;
4748 
4749 	if (addr)
4750 		pfx = nla_data(addr);
4751 
4752 	if (local) {
4753 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4754 			*peer_pfx = pfx;
4755 		pfx = nla_data(local);
4756 	}
4757 
4758 	return pfx;
4759 }
4760 
4761 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4762 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4763 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4764 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4765 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4766 	[IFA_RT_PRIORITY]	= { .len = sizeof(u32) },
4767 	[IFA_TARGET_NETNSID]	= { .type = NLA_S32 },
4768 	[IFA_PROTO]		= { .type = NLA_U8 },
4769 };
4770 
4771 static int
4772 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4773 		  struct netlink_ext_ack *extack)
4774 {
4775 	struct net *net = sock_net(skb->sk);
4776 	struct ifaddrmsg *ifm;
4777 	struct nlattr *tb[IFA_MAX+1];
4778 	struct in6_addr *pfx, *peer_pfx;
4779 	u32 ifa_flags;
4780 	int err;
4781 
4782 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4783 				     ifa_ipv6_policy, extack);
4784 	if (err < 0)
4785 		return err;
4786 
4787 	ifm = nlmsg_data(nlh);
4788 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4789 	if (!pfx)
4790 		return -EINVAL;
4791 
4792 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4793 
4794 	/* We ignore other flags so far. */
4795 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4796 
4797 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4798 			      ifm->ifa_prefixlen, extack);
4799 }
4800 
4801 static int modify_prefix_route(struct inet6_ifaddr *ifp,
4802 			       unsigned long expires, u32 flags,
4803 			       bool modify_peer)
4804 {
4805 	struct fib6_table *table;
4806 	struct fib6_info *f6i;
4807 	u32 prio;
4808 
4809 	f6i = addrconf_get_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4810 					ifp->prefix_len,
4811 					ifp->idev->dev, 0, RTF_DEFAULT, true);
4812 	if (!f6i)
4813 		return -ENOENT;
4814 
4815 	prio = ifp->rt_priority ? : IP6_RT_PRIO_ADDRCONF;
4816 	if (f6i->fib6_metric != prio) {
4817 		/* delete old one */
4818 		ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
4819 
4820 		/* add new one */
4821 		addrconf_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4822 				      ifp->prefix_len,
4823 				      ifp->rt_priority, ifp->idev->dev,
4824 				      expires, flags, GFP_KERNEL);
4825 	} else {
4826 		table = f6i->fib6_table;
4827 		spin_lock_bh(&table->tb6_lock);
4828 
4829 		if (!(flags & RTF_EXPIRES)) {
4830 			fib6_clean_expires(f6i);
4831 			fib6_remove_gc_list(f6i);
4832 		} else {
4833 			fib6_set_expires(f6i, expires);
4834 			fib6_add_gc_list(f6i);
4835 		}
4836 
4837 		spin_unlock_bh(&table->tb6_lock);
4838 
4839 		fib6_info_release(f6i);
4840 	}
4841 
4842 	return 0;
4843 }
4844 
4845 static int inet6_addr_modify(struct net *net, struct inet6_ifaddr *ifp,
4846 			     struct ifa6_config *cfg)
4847 {
4848 	u32 flags;
4849 	clock_t expires;
4850 	unsigned long timeout;
4851 	bool was_managetempaddr;
4852 	bool had_prefixroute;
4853 	bool new_peer = false;
4854 
4855 	ASSERT_RTNL();
4856 
4857 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
4858 		return -EINVAL;
4859 
4860 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR &&
4861 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4862 		return -EINVAL;
4863 
4864 	if (!(ifp->flags & IFA_F_TENTATIVE) || ifp->flags & IFA_F_DADFAILED)
4865 		cfg->ifa_flags &= ~IFA_F_OPTIMISTIC;
4866 
4867 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
4868 	if (addrconf_finite_timeout(timeout)) {
4869 		expires = jiffies_to_clock_t(timeout * HZ);
4870 		cfg->valid_lft = timeout;
4871 		flags = RTF_EXPIRES;
4872 	} else {
4873 		expires = 0;
4874 		flags = 0;
4875 		cfg->ifa_flags |= IFA_F_PERMANENT;
4876 	}
4877 
4878 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
4879 	if (addrconf_finite_timeout(timeout)) {
4880 		if (timeout == 0)
4881 			cfg->ifa_flags |= IFA_F_DEPRECATED;
4882 		cfg->preferred_lft = timeout;
4883 	}
4884 
4885 	if (cfg->peer_pfx &&
4886 	    memcmp(&ifp->peer_addr, cfg->peer_pfx, sizeof(struct in6_addr))) {
4887 		if (!ipv6_addr_any(&ifp->peer_addr))
4888 			cleanup_prefix_route(ifp, expires, true, true);
4889 		new_peer = true;
4890 	}
4891 
4892 	spin_lock_bh(&ifp->lock);
4893 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4894 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4895 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4896 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4897 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4898 			IFA_F_NOPREFIXROUTE);
4899 	ifp->flags |= cfg->ifa_flags;
4900 	WRITE_ONCE(ifp->tstamp, jiffies);
4901 	WRITE_ONCE(ifp->valid_lft, cfg->valid_lft);
4902 	WRITE_ONCE(ifp->prefered_lft, cfg->preferred_lft);
4903 	WRITE_ONCE(ifp->ifa_proto, cfg->ifa_proto);
4904 
4905 	if (cfg->rt_priority && cfg->rt_priority != ifp->rt_priority)
4906 		WRITE_ONCE(ifp->rt_priority, cfg->rt_priority);
4907 
4908 	if (new_peer)
4909 		ifp->peer_addr = *cfg->peer_pfx;
4910 
4911 	spin_unlock_bh(&ifp->lock);
4912 	if (!(ifp->flags&IFA_F_TENTATIVE))
4913 		ipv6_ifa_notify(0, ifp);
4914 
4915 	if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
4916 		int rc = -ENOENT;
4917 
4918 		if (had_prefixroute)
4919 			rc = modify_prefix_route(ifp, expires, flags, false);
4920 
4921 		/* prefix route could have been deleted; if so restore it */
4922 		if (rc == -ENOENT) {
4923 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4924 					      ifp->rt_priority, ifp->idev->dev,
4925 					      expires, flags, GFP_KERNEL);
4926 		}
4927 
4928 		if (had_prefixroute && !ipv6_addr_any(&ifp->peer_addr))
4929 			rc = modify_prefix_route(ifp, expires, flags, true);
4930 
4931 		if (rc == -ENOENT && !ipv6_addr_any(&ifp->peer_addr)) {
4932 			addrconf_prefix_route(&ifp->peer_addr, ifp->prefix_len,
4933 					      ifp->rt_priority, ifp->idev->dev,
4934 					      expires, flags, GFP_KERNEL);
4935 		}
4936 	} else if (had_prefixroute) {
4937 		enum cleanup_prefix_rt_t action;
4938 		unsigned long rt_expires;
4939 
4940 		write_lock_bh(&ifp->idev->lock);
4941 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4942 		write_unlock_bh(&ifp->idev->lock);
4943 
4944 		if (action != CLEANUP_PREFIX_RT_NOP) {
4945 			cleanup_prefix_route(ifp, rt_expires,
4946 				action == CLEANUP_PREFIX_RT_DEL, false);
4947 		}
4948 	}
4949 
4950 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4951 		if (was_managetempaddr &&
4952 		    !(ifp->flags & IFA_F_MANAGETEMPADDR)) {
4953 			cfg->valid_lft = 0;
4954 			cfg->preferred_lft = 0;
4955 		}
4956 		manage_tempaddrs(ifp->idev, ifp, cfg->valid_lft,
4957 				 cfg->preferred_lft, !was_managetempaddr,
4958 				 jiffies);
4959 	}
4960 
4961 	addrconf_verify_rtnl(net);
4962 
4963 	return 0;
4964 }
4965 
4966 static int
4967 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4968 		  struct netlink_ext_ack *extack)
4969 {
4970 	struct net *net = sock_net(skb->sk);
4971 	struct ifaddrmsg *ifm;
4972 	struct nlattr *tb[IFA_MAX+1];
4973 	struct in6_addr *peer_pfx;
4974 	struct inet6_ifaddr *ifa;
4975 	struct net_device *dev;
4976 	struct inet6_dev *idev;
4977 	struct ifa6_config cfg;
4978 	int err;
4979 
4980 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4981 				     ifa_ipv6_policy, extack);
4982 	if (err < 0)
4983 		return err;
4984 
4985 	memset(&cfg, 0, sizeof(cfg));
4986 
4987 	ifm = nlmsg_data(nlh);
4988 	cfg.pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4989 	if (!cfg.pfx)
4990 		return -EINVAL;
4991 
4992 	cfg.peer_pfx = peer_pfx;
4993 	cfg.plen = ifm->ifa_prefixlen;
4994 	if (tb[IFA_RT_PRIORITY])
4995 		cfg.rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
4996 
4997 	if (tb[IFA_PROTO])
4998 		cfg.ifa_proto = nla_get_u8(tb[IFA_PROTO]);
4999 
5000 	cfg.valid_lft = INFINITY_LIFE_TIME;
5001 	cfg.preferred_lft = INFINITY_LIFE_TIME;
5002 
5003 	if (tb[IFA_CACHEINFO]) {
5004 		struct ifa_cacheinfo *ci;
5005 
5006 		ci = nla_data(tb[IFA_CACHEINFO]);
5007 		cfg.valid_lft = ci->ifa_valid;
5008 		cfg.preferred_lft = ci->ifa_prefered;
5009 	}
5010 
5011 	dev =  __dev_get_by_index(net, ifm->ifa_index);
5012 	if (!dev) {
5013 		NL_SET_ERR_MSG_MOD(extack, "Unable to find the interface");
5014 		return -ENODEV;
5015 	}
5016 
5017 	if (tb[IFA_FLAGS])
5018 		cfg.ifa_flags = nla_get_u32(tb[IFA_FLAGS]);
5019 	else
5020 		cfg.ifa_flags = ifm->ifa_flags;
5021 
5022 	/* We ignore other flags so far. */
5023 	cfg.ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS |
5024 			 IFA_F_MANAGETEMPADDR | IFA_F_NOPREFIXROUTE |
5025 			 IFA_F_MCAUTOJOIN | IFA_F_OPTIMISTIC;
5026 
5027 	idev = ipv6_find_idev(dev);
5028 	if (IS_ERR(idev))
5029 		return PTR_ERR(idev);
5030 
5031 	if (!ipv6_allow_optimistic_dad(net, idev))
5032 		cfg.ifa_flags &= ~IFA_F_OPTIMISTIC;
5033 
5034 	if (cfg.ifa_flags & IFA_F_NODAD &&
5035 	    cfg.ifa_flags & IFA_F_OPTIMISTIC) {
5036 		NL_SET_ERR_MSG(extack, "IFA_F_NODAD and IFA_F_OPTIMISTIC are mutually exclusive");
5037 		return -EINVAL;
5038 	}
5039 
5040 	ifa = ipv6_get_ifaddr(net, cfg.pfx, dev, 1);
5041 	if (!ifa) {
5042 		/*
5043 		 * It would be best to check for !NLM_F_CREATE here but
5044 		 * userspace already relies on not having to provide this.
5045 		 */
5046 		return inet6_addr_add(net, ifm->ifa_index, &cfg, extack);
5047 	}
5048 
5049 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
5050 	    !(nlh->nlmsg_flags & NLM_F_REPLACE)) {
5051 		NL_SET_ERR_MSG_MOD(extack, "address already assigned");
5052 		err = -EEXIST;
5053 	} else {
5054 		err = inet6_addr_modify(net, ifa, &cfg);
5055 	}
5056 
5057 	in6_ifa_put(ifa);
5058 
5059 	return err;
5060 }
5061 
5062 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
5063 			  u8 scope, int ifindex)
5064 {
5065 	struct ifaddrmsg *ifm;
5066 
5067 	ifm = nlmsg_data(nlh);
5068 	ifm->ifa_family = AF_INET6;
5069 	ifm->ifa_prefixlen = prefixlen;
5070 	ifm->ifa_flags = flags;
5071 	ifm->ifa_scope = scope;
5072 	ifm->ifa_index = ifindex;
5073 }
5074 
5075 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
5076 			 unsigned long tstamp, u32 preferred, u32 valid)
5077 {
5078 	struct ifa_cacheinfo ci;
5079 
5080 	ci.cstamp = cstamp_delta(cstamp);
5081 	ci.tstamp = cstamp_delta(tstamp);
5082 	ci.ifa_prefered = preferred;
5083 	ci.ifa_valid = valid;
5084 
5085 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
5086 }
5087 
5088 static inline int rt_scope(int ifa_scope)
5089 {
5090 	if (ifa_scope & IFA_HOST)
5091 		return RT_SCOPE_HOST;
5092 	else if (ifa_scope & IFA_LINK)
5093 		return RT_SCOPE_LINK;
5094 	else if (ifa_scope & IFA_SITE)
5095 		return RT_SCOPE_SITE;
5096 	else
5097 		return RT_SCOPE_UNIVERSE;
5098 }
5099 
5100 static inline int inet6_ifaddr_msgsize(void)
5101 {
5102 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
5103 	       + nla_total_size(16) /* IFA_LOCAL */
5104 	       + nla_total_size(16) /* IFA_ADDRESS */
5105 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
5106 	       + nla_total_size(4)  /* IFA_FLAGS */
5107 	       + nla_total_size(1)  /* IFA_PROTO */
5108 	       + nla_total_size(4)  /* IFA_RT_PRIORITY */;
5109 }
5110 
5111 enum addr_type_t {
5112 	UNICAST_ADDR,
5113 	MULTICAST_ADDR,
5114 	ANYCAST_ADDR,
5115 };
5116 
5117 struct inet6_fill_args {
5118 	u32 portid;
5119 	u32 seq;
5120 	int event;
5121 	unsigned int flags;
5122 	int netnsid;
5123 	int ifindex;
5124 	enum addr_type_t type;
5125 };
5126 
5127 static int inet6_fill_ifaddr(struct sk_buff *skb,
5128 			     const struct inet6_ifaddr *ifa,
5129 			     struct inet6_fill_args *args)
5130 {
5131 	struct nlmsghdr *nlh;
5132 	u32 preferred, valid;
5133 	u32 flags, priority;
5134 	u8 proto;
5135 
5136 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5137 			sizeof(struct ifaddrmsg), args->flags);
5138 	if (!nlh)
5139 		return -EMSGSIZE;
5140 
5141 	flags = READ_ONCE(ifa->flags);
5142 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
5143 		      ifa->idev->dev->ifindex);
5144 
5145 	if (args->netnsid >= 0 &&
5146 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
5147 		goto error;
5148 
5149 	preferred = READ_ONCE(ifa->prefered_lft);
5150 	valid = READ_ONCE(ifa->valid_lft);
5151 
5152 	if (!((flags & IFA_F_PERMANENT) &&
5153 	      (preferred == INFINITY_LIFE_TIME))) {
5154 		if (preferred != INFINITY_LIFE_TIME) {
5155 			long tval = (jiffies - READ_ONCE(ifa->tstamp)) / HZ;
5156 
5157 			if (preferred > tval)
5158 				preferred -= tval;
5159 			else
5160 				preferred = 0;
5161 			if (valid != INFINITY_LIFE_TIME) {
5162 				if (valid > tval)
5163 					valid -= tval;
5164 				else
5165 					valid = 0;
5166 			}
5167 		}
5168 	} else {
5169 		preferred = INFINITY_LIFE_TIME;
5170 		valid = INFINITY_LIFE_TIME;
5171 	}
5172 
5173 	if (!ipv6_addr_any(&ifa->peer_addr)) {
5174 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
5175 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
5176 			goto error;
5177 	} else {
5178 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
5179 			goto error;
5180 	}
5181 
5182 	priority = READ_ONCE(ifa->rt_priority);
5183 	if (priority && nla_put_u32(skb, IFA_RT_PRIORITY, priority))
5184 		goto error;
5185 
5186 	if (put_cacheinfo(skb, ifa->cstamp, READ_ONCE(ifa->tstamp),
5187 			  preferred, valid) < 0)
5188 		goto error;
5189 
5190 	if (nla_put_u32(skb, IFA_FLAGS, flags) < 0)
5191 		goto error;
5192 
5193 	proto = READ_ONCE(ifa->ifa_proto);
5194 	if (proto && nla_put_u8(skb, IFA_PROTO, proto))
5195 		goto error;
5196 
5197 	nlmsg_end(skb, nlh);
5198 	return 0;
5199 
5200 error:
5201 	nlmsg_cancel(skb, nlh);
5202 	return -EMSGSIZE;
5203 }
5204 
5205 static int inet6_fill_ifmcaddr(struct sk_buff *skb,
5206 			       const struct ifmcaddr6 *ifmca,
5207 			       struct inet6_fill_args *args)
5208 {
5209 	int ifindex = ifmca->idev->dev->ifindex;
5210 	u8 scope = RT_SCOPE_UNIVERSE;
5211 	struct nlmsghdr *nlh;
5212 
5213 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
5214 		scope = RT_SCOPE_SITE;
5215 
5216 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5217 			sizeof(struct ifaddrmsg), args->flags);
5218 	if (!nlh)
5219 		return -EMSGSIZE;
5220 
5221 	if (args->netnsid >= 0 &&
5222 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) {
5223 		nlmsg_cancel(skb, nlh);
5224 		return -EMSGSIZE;
5225 	}
5226 
5227 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5228 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
5229 	    put_cacheinfo(skb, ifmca->mca_cstamp, READ_ONCE(ifmca->mca_tstamp),
5230 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5231 		nlmsg_cancel(skb, nlh);
5232 		return -EMSGSIZE;
5233 	}
5234 
5235 	nlmsg_end(skb, nlh);
5236 	return 0;
5237 }
5238 
5239 static int inet6_fill_ifacaddr(struct sk_buff *skb,
5240 			       const struct ifacaddr6 *ifaca,
5241 			       struct inet6_fill_args *args)
5242 {
5243 	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
5244 	int ifindex = dev ? dev->ifindex : 1;
5245 	u8 scope = RT_SCOPE_UNIVERSE;
5246 	struct nlmsghdr *nlh;
5247 
5248 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
5249 		scope = RT_SCOPE_SITE;
5250 
5251 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5252 			sizeof(struct ifaddrmsg), args->flags);
5253 	if (!nlh)
5254 		return -EMSGSIZE;
5255 
5256 	if (args->netnsid >= 0 &&
5257 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) {
5258 		nlmsg_cancel(skb, nlh);
5259 		return -EMSGSIZE;
5260 	}
5261 
5262 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5263 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
5264 	    put_cacheinfo(skb, ifaca->aca_cstamp, READ_ONCE(ifaca->aca_tstamp),
5265 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5266 		nlmsg_cancel(skb, nlh);
5267 		return -EMSGSIZE;
5268 	}
5269 
5270 	nlmsg_end(skb, nlh);
5271 	return 0;
5272 }
5273 
5274 /* called with rcu_read_lock() */
5275 static int in6_dump_addrs(const struct inet6_dev *idev, struct sk_buff *skb,
5276 			  struct netlink_callback *cb, int *s_ip_idx,
5277 			  struct inet6_fill_args *fillargs)
5278 {
5279 	const struct ifmcaddr6 *ifmca;
5280 	const struct ifacaddr6 *ifaca;
5281 	int ip_idx = 0;
5282 	int err = 0;
5283 
5284 	switch (fillargs->type) {
5285 	case UNICAST_ADDR: {
5286 		const struct inet6_ifaddr *ifa;
5287 		fillargs->event = RTM_NEWADDR;
5288 
5289 		/* unicast address incl. temp addr */
5290 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
5291 			if (ip_idx < *s_ip_idx)
5292 				goto next;
5293 			err = inet6_fill_ifaddr(skb, ifa, fillargs);
5294 			if (err < 0)
5295 				break;
5296 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
5297 next:
5298 			ip_idx++;
5299 		}
5300 		break;
5301 	}
5302 	case MULTICAST_ADDR:
5303 		fillargs->event = RTM_GETMULTICAST;
5304 
5305 		/* multicast address */
5306 		for (ifmca = rcu_dereference(idev->mc_list);
5307 		     ifmca;
5308 		     ifmca = rcu_dereference(ifmca->next), ip_idx++) {
5309 			if (ip_idx < *s_ip_idx)
5310 				continue;
5311 			err = inet6_fill_ifmcaddr(skb, ifmca, fillargs);
5312 			if (err < 0)
5313 				break;
5314 		}
5315 		break;
5316 	case ANYCAST_ADDR:
5317 		fillargs->event = RTM_GETANYCAST;
5318 		/* anycast address */
5319 		for (ifaca = rcu_dereference(idev->ac_list); ifaca;
5320 		     ifaca = rcu_dereference(ifaca->aca_next), ip_idx++) {
5321 			if (ip_idx < *s_ip_idx)
5322 				continue;
5323 			err = inet6_fill_ifacaddr(skb, ifaca, fillargs);
5324 			if (err < 0)
5325 				break;
5326 		}
5327 		break;
5328 	default:
5329 		break;
5330 	}
5331 	*s_ip_idx = err ? ip_idx : 0;
5332 	return err;
5333 }
5334 
5335 static int inet6_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
5336 				       struct inet6_fill_args *fillargs,
5337 				       struct net **tgt_net, struct sock *sk,
5338 				       struct netlink_callback *cb)
5339 {
5340 	struct netlink_ext_ack *extack = cb->extack;
5341 	struct nlattr *tb[IFA_MAX+1];
5342 	struct ifaddrmsg *ifm;
5343 	int err, i;
5344 
5345 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5346 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for address dump request");
5347 		return -EINVAL;
5348 	}
5349 
5350 	ifm = nlmsg_data(nlh);
5351 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5352 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address dump request");
5353 		return -EINVAL;
5354 	}
5355 
5356 	fillargs->ifindex = ifm->ifa_index;
5357 	if (fillargs->ifindex) {
5358 		cb->answer_flags |= NLM_F_DUMP_FILTERED;
5359 		fillargs->flags |= NLM_F_DUMP_FILTERED;
5360 	}
5361 
5362 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5363 					    ifa_ipv6_policy, extack);
5364 	if (err < 0)
5365 		return err;
5366 
5367 	for (i = 0; i <= IFA_MAX; ++i) {
5368 		if (!tb[i])
5369 			continue;
5370 
5371 		if (i == IFA_TARGET_NETNSID) {
5372 			struct net *net;
5373 
5374 			fillargs->netnsid = nla_get_s32(tb[i]);
5375 			net = rtnl_get_net_ns_capable(sk, fillargs->netnsid);
5376 			if (IS_ERR(net)) {
5377 				fillargs->netnsid = -1;
5378 				NL_SET_ERR_MSG_MOD(extack, "Invalid target network namespace id");
5379 				return PTR_ERR(net);
5380 			}
5381 			*tgt_net = net;
5382 		} else {
5383 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request");
5384 			return -EINVAL;
5385 		}
5386 	}
5387 
5388 	return 0;
5389 }
5390 
5391 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
5392 			   enum addr_type_t type)
5393 {
5394 	struct net *tgt_net = sock_net(skb->sk);
5395 	const struct nlmsghdr *nlh = cb->nlh;
5396 	struct inet6_fill_args fillargs = {
5397 		.portid = NETLINK_CB(cb->skb).portid,
5398 		.seq = cb->nlh->nlmsg_seq,
5399 		.flags = NLM_F_MULTI,
5400 		.netnsid = -1,
5401 		.type = type,
5402 	};
5403 	struct {
5404 		unsigned long ifindex;
5405 		int ip_idx;
5406 	} *ctx = (void *)cb->ctx;
5407 	struct net_device *dev;
5408 	struct inet6_dev *idev;
5409 	int err = 0;
5410 
5411 	rcu_read_lock();
5412 	if (cb->strict_check) {
5413 		err = inet6_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
5414 						  skb->sk, cb);
5415 		if (err < 0)
5416 			goto done;
5417 
5418 		err = 0;
5419 		if (fillargs.ifindex) {
5420 			dev = dev_get_by_index_rcu(tgt_net, fillargs.ifindex);
5421 			if (!dev) {
5422 				err = -ENODEV;
5423 				goto done;
5424 			}
5425 			idev = __in6_dev_get(dev);
5426 			if (idev)
5427 				err = in6_dump_addrs(idev, skb, cb,
5428 						     &ctx->ip_idx,
5429 						     &fillargs);
5430 			goto done;
5431 		}
5432 	}
5433 
5434 	cb->seq = inet6_base_seq(tgt_net);
5435 	for_each_netdev_dump(tgt_net, dev, ctx->ifindex) {
5436 		idev = __in6_dev_get(dev);
5437 		if (!idev)
5438 			continue;
5439 		err = in6_dump_addrs(idev, skb, cb, &ctx->ip_idx,
5440 				     &fillargs);
5441 		if (err < 0)
5442 			goto done;
5443 	}
5444 done:
5445 	rcu_read_unlock();
5446 	if (fillargs.netnsid >= 0)
5447 		put_net(tgt_net);
5448 
5449 	return err;
5450 }
5451 
5452 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
5453 {
5454 	enum addr_type_t type = UNICAST_ADDR;
5455 
5456 	return inet6_dump_addr(skb, cb, type);
5457 }
5458 
5459 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
5460 {
5461 	enum addr_type_t type = MULTICAST_ADDR;
5462 
5463 	return inet6_dump_addr(skb, cb, type);
5464 }
5465 
5466 
5467 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
5468 {
5469 	enum addr_type_t type = ANYCAST_ADDR;
5470 
5471 	return inet6_dump_addr(skb, cb, type);
5472 }
5473 
5474 static int inet6_rtm_valid_getaddr_req(struct sk_buff *skb,
5475 				       const struct nlmsghdr *nlh,
5476 				       struct nlattr **tb,
5477 				       struct netlink_ext_ack *extack)
5478 {
5479 	struct ifaddrmsg *ifm;
5480 	int i, err;
5481 
5482 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5483 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for get address request");
5484 		return -EINVAL;
5485 	}
5486 
5487 	if (!netlink_strict_get_check(skb))
5488 		return nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
5489 					      ifa_ipv6_policy, extack);
5490 
5491 	ifm = nlmsg_data(nlh);
5492 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5493 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get address request");
5494 		return -EINVAL;
5495 	}
5496 
5497 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5498 					    ifa_ipv6_policy, extack);
5499 	if (err)
5500 		return err;
5501 
5502 	for (i = 0; i <= IFA_MAX; i++) {
5503 		if (!tb[i])
5504 			continue;
5505 
5506 		switch (i) {
5507 		case IFA_TARGET_NETNSID:
5508 		case IFA_ADDRESS:
5509 		case IFA_LOCAL:
5510 			break;
5511 		default:
5512 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get address request");
5513 			return -EINVAL;
5514 		}
5515 	}
5516 
5517 	return 0;
5518 }
5519 
5520 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5521 			     struct netlink_ext_ack *extack)
5522 {
5523 	struct net *tgt_net = sock_net(in_skb->sk);
5524 	struct inet6_fill_args fillargs = {
5525 		.portid = NETLINK_CB(in_skb).portid,
5526 		.seq = nlh->nlmsg_seq,
5527 		.event = RTM_NEWADDR,
5528 		.flags = 0,
5529 		.netnsid = -1,
5530 	};
5531 	struct ifaddrmsg *ifm;
5532 	struct nlattr *tb[IFA_MAX+1];
5533 	struct in6_addr *addr = NULL, *peer;
5534 	struct net_device *dev = NULL;
5535 	struct inet6_ifaddr *ifa;
5536 	struct sk_buff *skb;
5537 	int err;
5538 
5539 	err = inet6_rtm_valid_getaddr_req(in_skb, nlh, tb, extack);
5540 	if (err < 0)
5541 		return err;
5542 
5543 	if (tb[IFA_TARGET_NETNSID]) {
5544 		fillargs.netnsid = nla_get_s32(tb[IFA_TARGET_NETNSID]);
5545 
5546 		tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(in_skb).sk,
5547 						  fillargs.netnsid);
5548 		if (IS_ERR(tgt_net))
5549 			return PTR_ERR(tgt_net);
5550 	}
5551 
5552 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
5553 	if (!addr) {
5554 		err = -EINVAL;
5555 		goto errout;
5556 	}
5557 	ifm = nlmsg_data(nlh);
5558 	if (ifm->ifa_index)
5559 		dev = dev_get_by_index(tgt_net, ifm->ifa_index);
5560 
5561 	ifa = ipv6_get_ifaddr(tgt_net, addr, dev, 1);
5562 	if (!ifa) {
5563 		err = -EADDRNOTAVAIL;
5564 		goto errout;
5565 	}
5566 
5567 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
5568 	if (!skb) {
5569 		err = -ENOBUFS;
5570 		goto errout_ifa;
5571 	}
5572 
5573 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5574 	if (err < 0) {
5575 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5576 		WARN_ON(err == -EMSGSIZE);
5577 		kfree_skb(skb);
5578 		goto errout_ifa;
5579 	}
5580 	err = rtnl_unicast(skb, tgt_net, NETLINK_CB(in_skb).portid);
5581 errout_ifa:
5582 	in6_ifa_put(ifa);
5583 errout:
5584 	dev_put(dev);
5585 	if (fillargs.netnsid >= 0)
5586 		put_net(tgt_net);
5587 
5588 	return err;
5589 }
5590 
5591 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
5592 {
5593 	struct sk_buff *skb;
5594 	struct net *net = dev_net(ifa->idev->dev);
5595 	struct inet6_fill_args fillargs = {
5596 		.portid = 0,
5597 		.seq = 0,
5598 		.event = event,
5599 		.flags = 0,
5600 		.netnsid = -1,
5601 	};
5602 	int err = -ENOBUFS;
5603 
5604 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
5605 	if (!skb)
5606 		goto errout;
5607 
5608 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5609 	if (err < 0) {
5610 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5611 		WARN_ON(err == -EMSGSIZE);
5612 		kfree_skb(skb);
5613 		goto errout;
5614 	}
5615 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5616 	return;
5617 errout:
5618 	if (err < 0)
5619 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5620 }
5621 
5622 static void ipv6_store_devconf(const struct ipv6_devconf *cnf,
5623 			       __s32 *array, int bytes)
5624 {
5625 	BUG_ON(bytes < (DEVCONF_MAX * 4));
5626 
5627 	memset(array, 0, bytes);
5628 	array[DEVCONF_FORWARDING] = READ_ONCE(cnf->forwarding);
5629 	array[DEVCONF_HOPLIMIT] = READ_ONCE(cnf->hop_limit);
5630 	array[DEVCONF_MTU6] = READ_ONCE(cnf->mtu6);
5631 	array[DEVCONF_ACCEPT_RA] = READ_ONCE(cnf->accept_ra);
5632 	array[DEVCONF_ACCEPT_REDIRECTS] = READ_ONCE(cnf->accept_redirects);
5633 	array[DEVCONF_AUTOCONF] = READ_ONCE(cnf->autoconf);
5634 	array[DEVCONF_DAD_TRANSMITS] = READ_ONCE(cnf->dad_transmits);
5635 	array[DEVCONF_RTR_SOLICITS] = READ_ONCE(cnf->rtr_solicits);
5636 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5637 		jiffies_to_msecs(READ_ONCE(cnf->rtr_solicit_interval));
5638 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5639 		jiffies_to_msecs(READ_ONCE(cnf->rtr_solicit_max_interval));
5640 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5641 		jiffies_to_msecs(READ_ONCE(cnf->rtr_solicit_delay));
5642 	array[DEVCONF_FORCE_MLD_VERSION] = READ_ONCE(cnf->force_mld_version);
5643 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5644 		jiffies_to_msecs(READ_ONCE(cnf->mldv1_unsolicited_report_interval));
5645 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5646 		jiffies_to_msecs(READ_ONCE(cnf->mldv2_unsolicited_report_interval));
5647 	array[DEVCONF_USE_TEMPADDR] = READ_ONCE(cnf->use_tempaddr);
5648 	array[DEVCONF_TEMP_VALID_LFT] = READ_ONCE(cnf->temp_valid_lft);
5649 	array[DEVCONF_TEMP_PREFERED_LFT] = READ_ONCE(cnf->temp_prefered_lft);
5650 	array[DEVCONF_REGEN_MAX_RETRY] = READ_ONCE(cnf->regen_max_retry);
5651 	array[DEVCONF_MAX_DESYNC_FACTOR] = READ_ONCE(cnf->max_desync_factor);
5652 	array[DEVCONF_MAX_ADDRESSES] = READ_ONCE(cnf->max_addresses);
5653 	array[DEVCONF_ACCEPT_RA_DEFRTR] = READ_ONCE(cnf->accept_ra_defrtr);
5654 	array[DEVCONF_RA_DEFRTR_METRIC] = READ_ONCE(cnf->ra_defrtr_metric);
5655 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] =
5656 		READ_ONCE(cnf->accept_ra_min_hop_limit);
5657 	array[DEVCONF_ACCEPT_RA_PINFO] = READ_ONCE(cnf->accept_ra_pinfo);
5658 #ifdef CONFIG_IPV6_ROUTER_PREF
5659 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = READ_ONCE(cnf->accept_ra_rtr_pref);
5660 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5661 		jiffies_to_msecs(READ_ONCE(cnf->rtr_probe_interval));
5662 #ifdef CONFIG_IPV6_ROUTE_INFO
5663 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] =
5664 		READ_ONCE(cnf->accept_ra_rt_info_min_plen);
5665 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] =
5666 		READ_ONCE(cnf->accept_ra_rt_info_max_plen);
5667 #endif
5668 #endif
5669 	array[DEVCONF_PROXY_NDP] = READ_ONCE(cnf->proxy_ndp);
5670 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] =
5671 		READ_ONCE(cnf->accept_source_route);
5672 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5673 	array[DEVCONF_OPTIMISTIC_DAD] = READ_ONCE(cnf->optimistic_dad);
5674 	array[DEVCONF_USE_OPTIMISTIC] = READ_ONCE(cnf->use_optimistic);
5675 #endif
5676 #ifdef CONFIG_IPV6_MROUTE
5677 	array[DEVCONF_MC_FORWARDING] = atomic_read(&cnf->mc_forwarding);
5678 #endif
5679 	array[DEVCONF_DISABLE_IPV6] = READ_ONCE(cnf->disable_ipv6);
5680 	array[DEVCONF_ACCEPT_DAD] = READ_ONCE(cnf->accept_dad);
5681 	array[DEVCONF_FORCE_TLLAO] = READ_ONCE(cnf->force_tllao);
5682 	array[DEVCONF_NDISC_NOTIFY] = READ_ONCE(cnf->ndisc_notify);
5683 	array[DEVCONF_SUPPRESS_FRAG_NDISC] =
5684 		READ_ONCE(cnf->suppress_frag_ndisc);
5685 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] =
5686 		READ_ONCE(cnf->accept_ra_from_local);
5687 	array[DEVCONF_ACCEPT_RA_MTU] = READ_ONCE(cnf->accept_ra_mtu);
5688 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] =
5689 		READ_ONCE(cnf->ignore_routes_with_linkdown);
5690 	/* we omit DEVCONF_STABLE_SECRET for now */
5691 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = READ_ONCE(cnf->use_oif_addrs_only);
5692 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] =
5693 		READ_ONCE(cnf->drop_unicast_in_l2_multicast);
5694 	array[DEVCONF_DROP_UNSOLICITED_NA] = READ_ONCE(cnf->drop_unsolicited_na);
5695 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = READ_ONCE(cnf->keep_addr_on_down);
5696 	array[DEVCONF_SEG6_ENABLED] = READ_ONCE(cnf->seg6_enabled);
5697 #ifdef CONFIG_IPV6_SEG6_HMAC
5698 	array[DEVCONF_SEG6_REQUIRE_HMAC] = READ_ONCE(cnf->seg6_require_hmac);
5699 #endif
5700 	array[DEVCONF_ENHANCED_DAD] = READ_ONCE(cnf->enhanced_dad);
5701 	array[DEVCONF_ADDR_GEN_MODE] = READ_ONCE(cnf->addr_gen_mode);
5702 	array[DEVCONF_DISABLE_POLICY] = READ_ONCE(cnf->disable_policy);
5703 	array[DEVCONF_NDISC_TCLASS] = READ_ONCE(cnf->ndisc_tclass);
5704 	array[DEVCONF_RPL_SEG_ENABLED] = READ_ONCE(cnf->rpl_seg_enabled);
5705 	array[DEVCONF_IOAM6_ENABLED] = READ_ONCE(cnf->ioam6_enabled);
5706 	array[DEVCONF_IOAM6_ID] = READ_ONCE(cnf->ioam6_id);
5707 	array[DEVCONF_IOAM6_ID_WIDE] = READ_ONCE(cnf->ioam6_id_wide);
5708 	array[DEVCONF_NDISC_EVICT_NOCARRIER] =
5709 		READ_ONCE(cnf->ndisc_evict_nocarrier);
5710 	array[DEVCONF_ACCEPT_UNTRACKED_NA] =
5711 		READ_ONCE(cnf->accept_untracked_na);
5712 	array[DEVCONF_ACCEPT_RA_MIN_LFT] = READ_ONCE(cnf->accept_ra_min_lft);
5713 }
5714 
5715 static inline size_t inet6_ifla6_size(void)
5716 {
5717 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5718 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5719 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5720 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5721 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5722 	     + nla_total_size(sizeof(struct in6_addr)) /* IFLA_INET6_TOKEN */
5723 	     + nla_total_size(1) /* IFLA_INET6_ADDR_GEN_MODE */
5724 	     + nla_total_size(4) /* IFLA_INET6_RA_MTU */
5725 	     + 0;
5726 }
5727 
5728 static inline size_t inet6_if_nlmsg_size(void)
5729 {
5730 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5731 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5732 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5733 	       + nla_total_size(4) /* IFLA_MTU */
5734 	       + nla_total_size(4) /* IFLA_LINK */
5735 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5736 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5737 }
5738 
5739 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5740 					int bytes)
5741 {
5742 	int i;
5743 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5744 	BUG_ON(pad < 0);
5745 
5746 	/* Use put_unaligned() because stats may not be aligned for u64. */
5747 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5748 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5749 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5750 
5751 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5752 }
5753 
5754 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5755 					int bytes, size_t syncpoff)
5756 {
5757 	int i, c;
5758 	u64 buff[IPSTATS_MIB_MAX];
5759 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5760 
5761 	BUG_ON(pad < 0);
5762 
5763 	memset(buff, 0, sizeof(buff));
5764 	buff[0] = IPSTATS_MIB_MAX;
5765 
5766 	for_each_possible_cpu(c) {
5767 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5768 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5769 	}
5770 
5771 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5772 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5773 }
5774 
5775 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5776 			     int bytes)
5777 {
5778 	switch (attrtype) {
5779 	case IFLA_INET6_STATS:
5780 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5781 				     offsetof(struct ipstats_mib, syncp));
5782 		break;
5783 	case IFLA_INET6_ICMP6STATS:
5784 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5785 		break;
5786 	}
5787 }
5788 
5789 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5790 				  u32 ext_filter_mask)
5791 {
5792 	struct ifla_cacheinfo ci;
5793 	struct nlattr *nla;
5794 	u32 ra_mtu;
5795 
5796 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, READ_ONCE(idev->if_flags)))
5797 		goto nla_put_failure;
5798 	ci.max_reasm_len = IPV6_MAXPLEN;
5799 	ci.tstamp = cstamp_delta(READ_ONCE(idev->tstamp));
5800 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5801 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5802 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5803 		goto nla_put_failure;
5804 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5805 	if (!nla)
5806 		goto nla_put_failure;
5807 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5808 
5809 	/* XXX - MC not implemented */
5810 
5811 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5812 		return 0;
5813 
5814 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5815 	if (!nla)
5816 		goto nla_put_failure;
5817 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5818 
5819 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5820 	if (!nla)
5821 		goto nla_put_failure;
5822 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5823 
5824 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5825 	if (!nla)
5826 		goto nla_put_failure;
5827 	read_lock_bh(&idev->lock);
5828 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5829 	read_unlock_bh(&idev->lock);
5830 
5831 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE,
5832 		       READ_ONCE(idev->cnf.addr_gen_mode)))
5833 		goto nla_put_failure;
5834 
5835 	ra_mtu = READ_ONCE(idev->ra_mtu);
5836 	if (ra_mtu && nla_put_u32(skb, IFLA_INET6_RA_MTU, ra_mtu))
5837 		goto nla_put_failure;
5838 
5839 	return 0;
5840 
5841 nla_put_failure:
5842 	return -EMSGSIZE;
5843 }
5844 
5845 static size_t inet6_get_link_af_size(const struct net_device *dev,
5846 				     u32 ext_filter_mask)
5847 {
5848 	if (!__in6_dev_get(dev))
5849 		return 0;
5850 
5851 	return inet6_ifla6_size();
5852 }
5853 
5854 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5855 			      u32 ext_filter_mask)
5856 {
5857 	struct inet6_dev *idev = __in6_dev_get(dev);
5858 
5859 	if (!idev)
5860 		return -ENODATA;
5861 
5862 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5863 		return -EMSGSIZE;
5864 
5865 	return 0;
5866 }
5867 
5868 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token,
5869 			     struct netlink_ext_ack *extack)
5870 {
5871 	struct inet6_ifaddr *ifp;
5872 	struct net_device *dev = idev->dev;
5873 	bool clear_token, update_rs = false;
5874 	struct in6_addr ll_addr;
5875 
5876 	ASSERT_RTNL();
5877 
5878 	if (!token)
5879 		return -EINVAL;
5880 
5881 	if (dev->flags & IFF_LOOPBACK) {
5882 		NL_SET_ERR_MSG_MOD(extack, "Device is loopback");
5883 		return -EINVAL;
5884 	}
5885 
5886 	if (dev->flags & IFF_NOARP) {
5887 		NL_SET_ERR_MSG_MOD(extack,
5888 				   "Device does not do neighbour discovery");
5889 		return -EINVAL;
5890 	}
5891 
5892 	if (!ipv6_accept_ra(idev)) {
5893 		NL_SET_ERR_MSG_MOD(extack,
5894 				   "Router advertisement is disabled on device");
5895 		return -EINVAL;
5896 	}
5897 
5898 	if (READ_ONCE(idev->cnf.rtr_solicits) == 0) {
5899 		NL_SET_ERR_MSG(extack,
5900 			       "Router solicitation is disabled on device");
5901 		return -EINVAL;
5902 	}
5903 
5904 	write_lock_bh(&idev->lock);
5905 
5906 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5907 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5908 
5909 	write_unlock_bh(&idev->lock);
5910 
5911 	clear_token = ipv6_addr_any(token);
5912 	if (clear_token)
5913 		goto update_lft;
5914 
5915 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5916 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5917 			     IFA_F_OPTIMISTIC)) {
5918 		/* If we're not ready, then normal ifup will take care
5919 		 * of this. Otherwise, we need to request our rs here.
5920 		 */
5921 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5922 		update_rs = true;
5923 	}
5924 
5925 update_lft:
5926 	write_lock_bh(&idev->lock);
5927 
5928 	if (update_rs) {
5929 		idev->if_flags |= IF_RS_SENT;
5930 		idev->rs_interval = rfc3315_s14_backoff_init(
5931 			READ_ONCE(idev->cnf.rtr_solicit_interval));
5932 		idev->rs_probes = 1;
5933 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5934 	}
5935 
5936 	/* Well, that's kinda nasty ... */
5937 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5938 		spin_lock(&ifp->lock);
5939 		if (ifp->tokenized) {
5940 			ifp->valid_lft = 0;
5941 			ifp->prefered_lft = 0;
5942 		}
5943 		spin_unlock(&ifp->lock);
5944 	}
5945 
5946 	write_unlock_bh(&idev->lock);
5947 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5948 	addrconf_verify_rtnl(dev_net(dev));
5949 	return 0;
5950 }
5951 
5952 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5953 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5954 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5955 	[IFLA_INET6_RA_MTU]		= { .type = NLA_REJECT,
5956 					    .reject_message =
5957 						"IFLA_INET6_RA_MTU can not be set" },
5958 };
5959 
5960 static int check_addr_gen_mode(int mode)
5961 {
5962 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5963 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5964 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5965 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5966 		return -EINVAL;
5967 	return 1;
5968 }
5969 
5970 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5971 				int mode)
5972 {
5973 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5974 	    !idev->cnf.stable_secret.initialized &&
5975 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5976 		return -EINVAL;
5977 	return 1;
5978 }
5979 
5980 static int inet6_validate_link_af(const struct net_device *dev,
5981 				  const struct nlattr *nla,
5982 				  struct netlink_ext_ack *extack)
5983 {
5984 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5985 	struct inet6_dev *idev = NULL;
5986 	int err;
5987 
5988 	if (dev) {
5989 		idev = __in6_dev_get(dev);
5990 		if (!idev)
5991 			return -EAFNOSUPPORT;
5992 	}
5993 
5994 	err = nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla,
5995 					  inet6_af_policy, extack);
5996 	if (err)
5997 		return err;
5998 
5999 	if (!tb[IFLA_INET6_TOKEN] && !tb[IFLA_INET6_ADDR_GEN_MODE])
6000 		return -EINVAL;
6001 
6002 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
6003 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
6004 
6005 		if (check_addr_gen_mode(mode) < 0)
6006 			return -EINVAL;
6007 		if (dev && check_stable_privacy(idev, dev_net(dev), mode) < 0)
6008 			return -EINVAL;
6009 	}
6010 
6011 	return 0;
6012 }
6013 
6014 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla,
6015 			     struct netlink_ext_ack *extack)
6016 {
6017 	struct inet6_dev *idev = __in6_dev_get(dev);
6018 	struct nlattr *tb[IFLA_INET6_MAX + 1];
6019 	int err;
6020 
6021 	if (!idev)
6022 		return -EAFNOSUPPORT;
6023 
6024 	if (nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
6025 		return -EINVAL;
6026 
6027 	if (tb[IFLA_INET6_TOKEN]) {
6028 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]),
6029 					extack);
6030 		if (err)
6031 			return err;
6032 	}
6033 
6034 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
6035 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
6036 
6037 		WRITE_ONCE(idev->cnf.addr_gen_mode, mode);
6038 	}
6039 
6040 	return 0;
6041 }
6042 
6043 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
6044 			     u32 portid, u32 seq, int event, unsigned int flags)
6045 {
6046 	struct net_device *dev = idev->dev;
6047 	struct ifinfomsg *hdr;
6048 	struct nlmsghdr *nlh;
6049 	int ifindex, iflink;
6050 	void *protoinfo;
6051 
6052 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
6053 	if (!nlh)
6054 		return -EMSGSIZE;
6055 
6056 	hdr = nlmsg_data(nlh);
6057 	hdr->ifi_family = AF_INET6;
6058 	hdr->__ifi_pad = 0;
6059 	hdr->ifi_type = dev->type;
6060 	ifindex = READ_ONCE(dev->ifindex);
6061 	hdr->ifi_index = ifindex;
6062 	hdr->ifi_flags = dev_get_flags(dev);
6063 	hdr->ifi_change = 0;
6064 
6065 	iflink = dev_get_iflink(dev);
6066 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
6067 	    (dev->addr_len &&
6068 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
6069 	    nla_put_u32(skb, IFLA_MTU, READ_ONCE(dev->mtu)) ||
6070 	    (ifindex != iflink &&
6071 	     nla_put_u32(skb, IFLA_LINK, iflink)) ||
6072 	    nla_put_u8(skb, IFLA_OPERSTATE,
6073 		       netif_running(dev) ? READ_ONCE(dev->operstate) : IF_OPER_DOWN))
6074 		goto nla_put_failure;
6075 	protoinfo = nla_nest_start_noflag(skb, IFLA_PROTINFO);
6076 	if (!protoinfo)
6077 		goto nla_put_failure;
6078 
6079 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
6080 		goto nla_put_failure;
6081 
6082 	nla_nest_end(skb, protoinfo);
6083 	nlmsg_end(skb, nlh);
6084 	return 0;
6085 
6086 nla_put_failure:
6087 	nlmsg_cancel(skb, nlh);
6088 	return -EMSGSIZE;
6089 }
6090 
6091 static int inet6_valid_dump_ifinfo(const struct nlmsghdr *nlh,
6092 				   struct netlink_ext_ack *extack)
6093 {
6094 	struct ifinfomsg *ifm;
6095 
6096 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
6097 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for link dump request");
6098 		return -EINVAL;
6099 	}
6100 
6101 	if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
6102 		NL_SET_ERR_MSG_MOD(extack, "Invalid data after header");
6103 		return -EINVAL;
6104 	}
6105 
6106 	ifm = nlmsg_data(nlh);
6107 	if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
6108 	    ifm->ifi_change || ifm->ifi_index) {
6109 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for dump request");
6110 		return -EINVAL;
6111 	}
6112 
6113 	return 0;
6114 }
6115 
6116 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
6117 {
6118 	struct net *net = sock_net(skb->sk);
6119 	struct {
6120 		unsigned long ifindex;
6121 	} *ctx = (void *)cb->ctx;
6122 	struct net_device *dev;
6123 	struct inet6_dev *idev;
6124 	int err;
6125 
6126 	/* only requests using strict checking can pass data to
6127 	 * influence the dump
6128 	 */
6129 	if (cb->strict_check) {
6130 		err = inet6_valid_dump_ifinfo(cb->nlh, cb->extack);
6131 
6132 		if (err < 0)
6133 			return err;
6134 	}
6135 
6136 	err = 0;
6137 	rcu_read_lock();
6138 	for_each_netdev_dump(net, dev, ctx->ifindex) {
6139 		idev = __in6_dev_get(dev);
6140 		if (!idev)
6141 			continue;
6142 		err = inet6_fill_ifinfo(skb, idev,
6143 					NETLINK_CB(cb->skb).portid,
6144 					cb->nlh->nlmsg_seq,
6145 					RTM_NEWLINK, NLM_F_MULTI);
6146 		if (err < 0)
6147 			break;
6148 	}
6149 	rcu_read_unlock();
6150 
6151 	return err;
6152 }
6153 
6154 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
6155 {
6156 	struct sk_buff *skb;
6157 	struct net *net = dev_net(idev->dev);
6158 	int err = -ENOBUFS;
6159 
6160 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
6161 	if (!skb)
6162 		goto errout;
6163 
6164 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
6165 	if (err < 0) {
6166 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
6167 		WARN_ON(err == -EMSGSIZE);
6168 		kfree_skb(skb);
6169 		goto errout;
6170 	}
6171 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
6172 	return;
6173 errout:
6174 	if (err < 0)
6175 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
6176 }
6177 
6178 static inline size_t inet6_prefix_nlmsg_size(void)
6179 {
6180 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
6181 	       + nla_total_size(sizeof(struct in6_addr))
6182 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
6183 }
6184 
6185 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
6186 			     struct prefix_info *pinfo, u32 portid, u32 seq,
6187 			     int event, unsigned int flags)
6188 {
6189 	struct prefixmsg *pmsg;
6190 	struct nlmsghdr *nlh;
6191 	struct prefix_cacheinfo	ci;
6192 
6193 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
6194 	if (!nlh)
6195 		return -EMSGSIZE;
6196 
6197 	pmsg = nlmsg_data(nlh);
6198 	pmsg->prefix_family = AF_INET6;
6199 	pmsg->prefix_pad1 = 0;
6200 	pmsg->prefix_pad2 = 0;
6201 	pmsg->prefix_ifindex = idev->dev->ifindex;
6202 	pmsg->prefix_len = pinfo->prefix_len;
6203 	pmsg->prefix_type = pinfo->type;
6204 	pmsg->prefix_pad3 = 0;
6205 	pmsg->prefix_flags = pinfo->flags;
6206 
6207 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
6208 		goto nla_put_failure;
6209 	ci.preferred_time = ntohl(pinfo->prefered);
6210 	ci.valid_time = ntohl(pinfo->valid);
6211 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
6212 		goto nla_put_failure;
6213 	nlmsg_end(skb, nlh);
6214 	return 0;
6215 
6216 nla_put_failure:
6217 	nlmsg_cancel(skb, nlh);
6218 	return -EMSGSIZE;
6219 }
6220 
6221 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
6222 			 struct prefix_info *pinfo)
6223 {
6224 	struct sk_buff *skb;
6225 	struct net *net = dev_net(idev->dev);
6226 	int err = -ENOBUFS;
6227 
6228 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
6229 	if (!skb)
6230 		goto errout;
6231 
6232 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
6233 	if (err < 0) {
6234 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
6235 		WARN_ON(err == -EMSGSIZE);
6236 		kfree_skb(skb);
6237 		goto errout;
6238 	}
6239 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
6240 	return;
6241 errout:
6242 	if (err < 0)
6243 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
6244 }
6245 
6246 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6247 {
6248 	struct net *net = dev_net(ifp->idev->dev);
6249 
6250 	if (event)
6251 		ASSERT_RTNL();
6252 
6253 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
6254 
6255 	switch (event) {
6256 	case RTM_NEWADDR:
6257 		/*
6258 		 * If the address was optimistic we inserted the route at the
6259 		 * start of our DAD process, so we don't need to do it again.
6260 		 * If the device was taken down in the middle of the DAD
6261 		 * cycle there is a race where we could get here without a
6262 		 * host route, so nothing to insert. That will be fixed when
6263 		 * the device is brought up.
6264 		 */
6265 		if (ifp->rt && !rcu_access_pointer(ifp->rt->fib6_node)) {
6266 			ip6_ins_rt(net, ifp->rt);
6267 		} else if (!ifp->rt && (ifp->idev->dev->flags & IFF_UP)) {
6268 			pr_warn("BUG: Address %pI6c on device %s is missing its host route.\n",
6269 				&ifp->addr, ifp->idev->dev->name);
6270 		}
6271 
6272 		if (ifp->idev->cnf.forwarding)
6273 			addrconf_join_anycast(ifp);
6274 		if (!ipv6_addr_any(&ifp->peer_addr))
6275 			addrconf_prefix_route(&ifp->peer_addr, 128,
6276 					      ifp->rt_priority, ifp->idev->dev,
6277 					      0, 0, GFP_ATOMIC);
6278 		break;
6279 	case RTM_DELADDR:
6280 		if (ifp->idev->cnf.forwarding)
6281 			addrconf_leave_anycast(ifp);
6282 		addrconf_leave_solict(ifp->idev, &ifp->addr);
6283 		if (!ipv6_addr_any(&ifp->peer_addr)) {
6284 			struct fib6_info *rt;
6285 
6286 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
6287 						       ifp->idev->dev, 0, 0,
6288 						       false);
6289 			if (rt)
6290 				ip6_del_rt(net, rt, false);
6291 		}
6292 		if (ifp->rt) {
6293 			ip6_del_rt(net, ifp->rt, false);
6294 			ifp->rt = NULL;
6295 		}
6296 		rt_genid_bump_ipv6(net);
6297 		break;
6298 	}
6299 	atomic_inc(&net->ipv6.dev_addr_genid);
6300 }
6301 
6302 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6303 {
6304 	if (likely(ifp->idev->dead == 0))
6305 		__ipv6_ifa_notify(event, ifp);
6306 }
6307 
6308 #ifdef CONFIG_SYSCTL
6309 
6310 static int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
6311 		void *buffer, size_t *lenp, loff_t *ppos)
6312 {
6313 	int *valp = ctl->data;
6314 	int val = *valp;
6315 	loff_t pos = *ppos;
6316 	struct ctl_table lctl;
6317 	int ret;
6318 
6319 	/*
6320 	 * ctl->data points to idev->cnf.forwarding, we should
6321 	 * not modify it until we get the rtnl lock.
6322 	 */
6323 	lctl = *ctl;
6324 	lctl.data = &val;
6325 
6326 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6327 
6328 	if (write)
6329 		ret = addrconf_fixup_forwarding(ctl, valp, val);
6330 	if (ret)
6331 		*ppos = pos;
6332 	return ret;
6333 }
6334 
6335 static int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
6336 		void *buffer, size_t *lenp, loff_t *ppos)
6337 {
6338 	struct inet6_dev *idev = ctl->extra1;
6339 	int min_mtu = IPV6_MIN_MTU;
6340 	struct ctl_table lctl;
6341 
6342 	lctl = *ctl;
6343 	lctl.extra1 = &min_mtu;
6344 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
6345 
6346 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
6347 }
6348 
6349 static void dev_disable_change(struct inet6_dev *idev)
6350 {
6351 	struct netdev_notifier_info info;
6352 
6353 	if (!idev || !idev->dev)
6354 		return;
6355 
6356 	netdev_notifier_info_init(&info, idev->dev);
6357 	if (idev->cnf.disable_ipv6)
6358 		addrconf_notify(NULL, NETDEV_DOWN, &info);
6359 	else
6360 		addrconf_notify(NULL, NETDEV_UP, &info);
6361 }
6362 
6363 static void addrconf_disable_change(struct net *net, __s32 newf)
6364 {
6365 	struct net_device *dev;
6366 	struct inet6_dev *idev;
6367 
6368 	for_each_netdev(net, dev) {
6369 		idev = __in6_dev_get(dev);
6370 		if (idev) {
6371 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
6372 
6373 			WRITE_ONCE(idev->cnf.disable_ipv6, newf);
6374 			if (changed)
6375 				dev_disable_change(idev);
6376 		}
6377 	}
6378 }
6379 
6380 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
6381 {
6382 	struct net *net = (struct net *)table->extra2;
6383 	int old;
6384 
6385 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
6386 		WRITE_ONCE(*p, newf);
6387 		return 0;
6388 	}
6389 
6390 	if (!rtnl_trylock())
6391 		return restart_syscall();
6392 
6393 	old = *p;
6394 	WRITE_ONCE(*p, newf);
6395 
6396 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
6397 		WRITE_ONCE(net->ipv6.devconf_dflt->disable_ipv6, newf);
6398 		addrconf_disable_change(net, newf);
6399 	} else if ((!newf) ^ (!old))
6400 		dev_disable_change((struct inet6_dev *)table->extra1);
6401 
6402 	rtnl_unlock();
6403 	return 0;
6404 }
6405 
6406 static int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
6407 		void *buffer, size_t *lenp, loff_t *ppos)
6408 {
6409 	int *valp = ctl->data;
6410 	int val = *valp;
6411 	loff_t pos = *ppos;
6412 	struct ctl_table lctl;
6413 	int ret;
6414 
6415 	/*
6416 	 * ctl->data points to idev->cnf.disable_ipv6, we should
6417 	 * not modify it until we get the rtnl lock.
6418 	 */
6419 	lctl = *ctl;
6420 	lctl.data = &val;
6421 
6422 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6423 
6424 	if (write)
6425 		ret = addrconf_disable_ipv6(ctl, valp, val);
6426 	if (ret)
6427 		*ppos = pos;
6428 	return ret;
6429 }
6430 
6431 static int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
6432 		void *buffer, size_t *lenp, loff_t *ppos)
6433 {
6434 	int *valp = ctl->data;
6435 	int ret;
6436 	int old, new;
6437 
6438 	old = *valp;
6439 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
6440 	new = *valp;
6441 
6442 	if (write && old != new) {
6443 		struct net *net = ctl->extra2;
6444 
6445 		if (!rtnl_trylock())
6446 			return restart_syscall();
6447 
6448 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
6449 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6450 						     NETCONFA_PROXY_NEIGH,
6451 						     NETCONFA_IFINDEX_DEFAULT,
6452 						     net->ipv6.devconf_dflt);
6453 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
6454 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6455 						     NETCONFA_PROXY_NEIGH,
6456 						     NETCONFA_IFINDEX_ALL,
6457 						     net->ipv6.devconf_all);
6458 		else {
6459 			struct inet6_dev *idev = ctl->extra1;
6460 
6461 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6462 						     NETCONFA_PROXY_NEIGH,
6463 						     idev->dev->ifindex,
6464 						     &idev->cnf);
6465 		}
6466 		rtnl_unlock();
6467 	}
6468 
6469 	return ret;
6470 }
6471 
6472 static int addrconf_sysctl_addr_gen_mode(struct ctl_table *ctl, int write,
6473 					 void *buffer, size_t *lenp,
6474 					 loff_t *ppos)
6475 {
6476 	int ret = 0;
6477 	u32 new_val;
6478 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
6479 	struct net *net = (struct net *)ctl->extra2;
6480 	struct ctl_table tmp = {
6481 		.data = &new_val,
6482 		.maxlen = sizeof(new_val),
6483 		.mode = ctl->mode,
6484 	};
6485 
6486 	if (!rtnl_trylock())
6487 		return restart_syscall();
6488 
6489 	new_val = *((u32 *)ctl->data);
6490 
6491 	ret = proc_douintvec(&tmp, write, buffer, lenp, ppos);
6492 	if (ret != 0)
6493 		goto out;
6494 
6495 	if (write) {
6496 		if (check_addr_gen_mode(new_val) < 0) {
6497 			ret = -EINVAL;
6498 			goto out;
6499 		}
6500 
6501 		if (idev) {
6502 			if (check_stable_privacy(idev, net, new_val) < 0) {
6503 				ret = -EINVAL;
6504 				goto out;
6505 			}
6506 
6507 			if (idev->cnf.addr_gen_mode != new_val) {
6508 				WRITE_ONCE(idev->cnf.addr_gen_mode, new_val);
6509 				addrconf_init_auto_addrs(idev->dev);
6510 			}
6511 		} else if (&net->ipv6.devconf_all->addr_gen_mode == ctl->data) {
6512 			struct net_device *dev;
6513 
6514 			WRITE_ONCE(net->ipv6.devconf_dflt->addr_gen_mode, new_val);
6515 			for_each_netdev(net, dev) {
6516 				idev = __in6_dev_get(dev);
6517 				if (idev &&
6518 				    idev->cnf.addr_gen_mode != new_val) {
6519 					WRITE_ONCE(idev->cnf.addr_gen_mode,
6520 						  new_val);
6521 					addrconf_init_auto_addrs(idev->dev);
6522 				}
6523 			}
6524 		}
6525 
6526 		WRITE_ONCE(*((u32 *)ctl->data), new_val);
6527 	}
6528 
6529 out:
6530 	rtnl_unlock();
6531 
6532 	return ret;
6533 }
6534 
6535 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
6536 					 void *buffer, size_t *lenp,
6537 					 loff_t *ppos)
6538 {
6539 	int err;
6540 	struct in6_addr addr;
6541 	char str[IPV6_MAX_STRLEN];
6542 	struct ctl_table lctl = *ctl;
6543 	struct net *net = ctl->extra2;
6544 	struct ipv6_stable_secret *secret = ctl->data;
6545 
6546 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
6547 		return -EIO;
6548 
6549 	lctl.maxlen = IPV6_MAX_STRLEN;
6550 	lctl.data = str;
6551 
6552 	if (!rtnl_trylock())
6553 		return restart_syscall();
6554 
6555 	if (!write && !secret->initialized) {
6556 		err = -EIO;
6557 		goto out;
6558 	}
6559 
6560 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
6561 	if (err >= sizeof(str)) {
6562 		err = -EIO;
6563 		goto out;
6564 	}
6565 
6566 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
6567 	if (err || !write)
6568 		goto out;
6569 
6570 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
6571 		err = -EIO;
6572 		goto out;
6573 	}
6574 
6575 	secret->initialized = true;
6576 	secret->secret = addr;
6577 
6578 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
6579 		struct net_device *dev;
6580 
6581 		for_each_netdev(net, dev) {
6582 			struct inet6_dev *idev = __in6_dev_get(dev);
6583 
6584 			if (idev) {
6585 				WRITE_ONCE(idev->cnf.addr_gen_mode,
6586 					   IN6_ADDR_GEN_MODE_STABLE_PRIVACY);
6587 			}
6588 		}
6589 	} else {
6590 		struct inet6_dev *idev = ctl->extra1;
6591 
6592 		WRITE_ONCE(idev->cnf.addr_gen_mode,
6593 			   IN6_ADDR_GEN_MODE_STABLE_PRIVACY);
6594 	}
6595 
6596 out:
6597 	rtnl_unlock();
6598 
6599 	return err;
6600 }
6601 
6602 static
6603 int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
6604 						int write, void *buffer,
6605 						size_t *lenp,
6606 						loff_t *ppos)
6607 {
6608 	int *valp = ctl->data;
6609 	int val = *valp;
6610 	loff_t pos = *ppos;
6611 	struct ctl_table lctl;
6612 	int ret;
6613 
6614 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
6615 	 * we should not modify it until we get the rtnl lock.
6616 	 */
6617 	lctl = *ctl;
6618 	lctl.data = &val;
6619 
6620 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6621 
6622 	if (write)
6623 		ret = addrconf_fixup_linkdown(ctl, valp, val);
6624 	if (ret)
6625 		*ppos = pos;
6626 	return ret;
6627 }
6628 
6629 static
6630 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
6631 {
6632 	if (rt) {
6633 		if (action)
6634 			rt->dst.flags |= DST_NOPOLICY;
6635 		else
6636 			rt->dst.flags &= ~DST_NOPOLICY;
6637 	}
6638 }
6639 
6640 static
6641 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
6642 {
6643 	struct inet6_ifaddr *ifa;
6644 
6645 	read_lock_bh(&idev->lock);
6646 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
6647 		spin_lock(&ifa->lock);
6648 		if (ifa->rt) {
6649 			/* host routes only use builtin fib6_nh */
6650 			struct fib6_nh *nh = ifa->rt->fib6_nh;
6651 			int cpu;
6652 
6653 			rcu_read_lock();
6654 			ifa->rt->dst_nopolicy = val ? true : false;
6655 			if (nh->rt6i_pcpu) {
6656 				for_each_possible_cpu(cpu) {
6657 					struct rt6_info **rtp;
6658 
6659 					rtp = per_cpu_ptr(nh->rt6i_pcpu, cpu);
6660 					addrconf_set_nopolicy(*rtp, val);
6661 				}
6662 			}
6663 			rcu_read_unlock();
6664 		}
6665 		spin_unlock(&ifa->lock);
6666 	}
6667 	read_unlock_bh(&idev->lock);
6668 }
6669 
6670 static
6671 int addrconf_disable_policy(struct ctl_table *ctl, int *valp, int val)
6672 {
6673 	struct net *net = (struct net *)ctl->extra2;
6674 	struct inet6_dev *idev;
6675 
6676 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
6677 		WRITE_ONCE(*valp, val);
6678 		return 0;
6679 	}
6680 
6681 	if (!rtnl_trylock())
6682 		return restart_syscall();
6683 
6684 	WRITE_ONCE(*valp, val);
6685 
6686 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
6687 		struct net_device *dev;
6688 
6689 		for_each_netdev(net, dev) {
6690 			idev = __in6_dev_get(dev);
6691 			if (idev)
6692 				addrconf_disable_policy_idev(idev, val);
6693 		}
6694 	} else {
6695 		idev = (struct inet6_dev *)ctl->extra1;
6696 		addrconf_disable_policy_idev(idev, val);
6697 	}
6698 
6699 	rtnl_unlock();
6700 	return 0;
6701 }
6702 
6703 static int addrconf_sysctl_disable_policy(struct ctl_table *ctl, int write,
6704 				   void *buffer, size_t *lenp, loff_t *ppos)
6705 {
6706 	int *valp = ctl->data;
6707 	int val = *valp;
6708 	loff_t pos = *ppos;
6709 	struct ctl_table lctl;
6710 	int ret;
6711 
6712 	lctl = *ctl;
6713 	lctl.data = &val;
6714 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6715 
6716 	if (write && (*valp != val))
6717 		ret = addrconf_disable_policy(ctl, valp, val);
6718 
6719 	if (ret)
6720 		*ppos = pos;
6721 
6722 	return ret;
6723 }
6724 
6725 static int minus_one = -1;
6726 static const int two_five_five = 255;
6727 static u32 ioam6_if_id_max = U16_MAX;
6728 
6729 static const struct ctl_table addrconf_sysctl[] = {
6730 	{
6731 		.procname	= "forwarding",
6732 		.data		= &ipv6_devconf.forwarding,
6733 		.maxlen		= sizeof(int),
6734 		.mode		= 0644,
6735 		.proc_handler	= addrconf_sysctl_forward,
6736 	},
6737 	{
6738 		.procname	= "hop_limit",
6739 		.data		= &ipv6_devconf.hop_limit,
6740 		.maxlen		= sizeof(int),
6741 		.mode		= 0644,
6742 		.proc_handler	= proc_dointvec_minmax,
6743 		.extra1		= (void *)SYSCTL_ONE,
6744 		.extra2		= (void *)&two_five_five,
6745 	},
6746 	{
6747 		.procname	= "mtu",
6748 		.data		= &ipv6_devconf.mtu6,
6749 		.maxlen		= sizeof(int),
6750 		.mode		= 0644,
6751 		.proc_handler	= addrconf_sysctl_mtu,
6752 	},
6753 	{
6754 		.procname	= "accept_ra",
6755 		.data		= &ipv6_devconf.accept_ra,
6756 		.maxlen		= sizeof(int),
6757 		.mode		= 0644,
6758 		.proc_handler	= proc_dointvec,
6759 	},
6760 	{
6761 		.procname	= "accept_redirects",
6762 		.data		= &ipv6_devconf.accept_redirects,
6763 		.maxlen		= sizeof(int),
6764 		.mode		= 0644,
6765 		.proc_handler	= proc_dointvec,
6766 	},
6767 	{
6768 		.procname	= "autoconf",
6769 		.data		= &ipv6_devconf.autoconf,
6770 		.maxlen		= sizeof(int),
6771 		.mode		= 0644,
6772 		.proc_handler	= proc_dointvec,
6773 	},
6774 	{
6775 		.procname	= "dad_transmits",
6776 		.data		= &ipv6_devconf.dad_transmits,
6777 		.maxlen		= sizeof(int),
6778 		.mode		= 0644,
6779 		.proc_handler	= proc_dointvec,
6780 	},
6781 	{
6782 		.procname	= "router_solicitations",
6783 		.data		= &ipv6_devconf.rtr_solicits,
6784 		.maxlen		= sizeof(int),
6785 		.mode		= 0644,
6786 		.proc_handler	= proc_dointvec_minmax,
6787 		.extra1		= &minus_one,
6788 	},
6789 	{
6790 		.procname	= "router_solicitation_interval",
6791 		.data		= &ipv6_devconf.rtr_solicit_interval,
6792 		.maxlen		= sizeof(int),
6793 		.mode		= 0644,
6794 		.proc_handler	= proc_dointvec_jiffies,
6795 	},
6796 	{
6797 		.procname	= "router_solicitation_max_interval",
6798 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6799 		.maxlen		= sizeof(int),
6800 		.mode		= 0644,
6801 		.proc_handler	= proc_dointvec_jiffies,
6802 	},
6803 	{
6804 		.procname	= "router_solicitation_delay",
6805 		.data		= &ipv6_devconf.rtr_solicit_delay,
6806 		.maxlen		= sizeof(int),
6807 		.mode		= 0644,
6808 		.proc_handler	= proc_dointvec_jiffies,
6809 	},
6810 	{
6811 		.procname	= "force_mld_version",
6812 		.data		= &ipv6_devconf.force_mld_version,
6813 		.maxlen		= sizeof(int),
6814 		.mode		= 0644,
6815 		.proc_handler	= proc_dointvec,
6816 	},
6817 	{
6818 		.procname	= "mldv1_unsolicited_report_interval",
6819 		.data		=
6820 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6821 		.maxlen		= sizeof(int),
6822 		.mode		= 0644,
6823 		.proc_handler	= proc_dointvec_ms_jiffies,
6824 	},
6825 	{
6826 		.procname	= "mldv2_unsolicited_report_interval",
6827 		.data		=
6828 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6829 		.maxlen		= sizeof(int),
6830 		.mode		= 0644,
6831 		.proc_handler	= proc_dointvec_ms_jiffies,
6832 	},
6833 	{
6834 		.procname	= "use_tempaddr",
6835 		.data		= &ipv6_devconf.use_tempaddr,
6836 		.maxlen		= sizeof(int),
6837 		.mode		= 0644,
6838 		.proc_handler	= proc_dointvec,
6839 	},
6840 	{
6841 		.procname	= "temp_valid_lft",
6842 		.data		= &ipv6_devconf.temp_valid_lft,
6843 		.maxlen		= sizeof(int),
6844 		.mode		= 0644,
6845 		.proc_handler	= proc_dointvec,
6846 	},
6847 	{
6848 		.procname	= "temp_prefered_lft",
6849 		.data		= &ipv6_devconf.temp_prefered_lft,
6850 		.maxlen		= sizeof(int),
6851 		.mode		= 0644,
6852 		.proc_handler	= proc_dointvec,
6853 	},
6854 	{
6855 		.procname       = "regen_min_advance",
6856 		.data           = &ipv6_devconf.regen_min_advance,
6857 		.maxlen         = sizeof(int),
6858 		.mode           = 0644,
6859 		.proc_handler   = proc_dointvec,
6860 	},
6861 	{
6862 		.procname	= "regen_max_retry",
6863 		.data		= &ipv6_devconf.regen_max_retry,
6864 		.maxlen		= sizeof(int),
6865 		.mode		= 0644,
6866 		.proc_handler	= proc_dointvec,
6867 	},
6868 	{
6869 		.procname	= "max_desync_factor",
6870 		.data		= &ipv6_devconf.max_desync_factor,
6871 		.maxlen		= sizeof(int),
6872 		.mode		= 0644,
6873 		.proc_handler	= proc_dointvec,
6874 	},
6875 	{
6876 		.procname	= "max_addresses",
6877 		.data		= &ipv6_devconf.max_addresses,
6878 		.maxlen		= sizeof(int),
6879 		.mode		= 0644,
6880 		.proc_handler	= proc_dointvec,
6881 	},
6882 	{
6883 		.procname	= "accept_ra_defrtr",
6884 		.data		= &ipv6_devconf.accept_ra_defrtr,
6885 		.maxlen		= sizeof(int),
6886 		.mode		= 0644,
6887 		.proc_handler	= proc_dointvec,
6888 	},
6889 	{
6890 		.procname	= "ra_defrtr_metric",
6891 		.data		= &ipv6_devconf.ra_defrtr_metric,
6892 		.maxlen		= sizeof(u32),
6893 		.mode		= 0644,
6894 		.proc_handler	= proc_douintvec_minmax,
6895 		.extra1		= (void *)SYSCTL_ONE,
6896 	},
6897 	{
6898 		.procname	= "accept_ra_min_hop_limit",
6899 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6900 		.maxlen		= sizeof(int),
6901 		.mode		= 0644,
6902 		.proc_handler	= proc_dointvec,
6903 	},
6904 	{
6905 		.procname	= "accept_ra_min_lft",
6906 		.data		= &ipv6_devconf.accept_ra_min_lft,
6907 		.maxlen		= sizeof(int),
6908 		.mode		= 0644,
6909 		.proc_handler	= proc_dointvec,
6910 	},
6911 	{
6912 		.procname	= "accept_ra_pinfo",
6913 		.data		= &ipv6_devconf.accept_ra_pinfo,
6914 		.maxlen		= sizeof(int),
6915 		.mode		= 0644,
6916 		.proc_handler	= proc_dointvec,
6917 	},
6918 	{
6919 		.procname	= "ra_honor_pio_life",
6920 		.data		= &ipv6_devconf.ra_honor_pio_life,
6921 		.maxlen		= sizeof(u8),
6922 		.mode		= 0644,
6923 		.proc_handler	= proc_dou8vec_minmax,
6924 		.extra1		= SYSCTL_ZERO,
6925 		.extra2		= SYSCTL_ONE,
6926 	},
6927 #ifdef CONFIG_IPV6_ROUTER_PREF
6928 	{
6929 		.procname	= "accept_ra_rtr_pref",
6930 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6931 		.maxlen		= sizeof(int),
6932 		.mode		= 0644,
6933 		.proc_handler	= proc_dointvec,
6934 	},
6935 	{
6936 		.procname	= "router_probe_interval",
6937 		.data		= &ipv6_devconf.rtr_probe_interval,
6938 		.maxlen		= sizeof(int),
6939 		.mode		= 0644,
6940 		.proc_handler	= proc_dointvec_jiffies,
6941 	},
6942 #ifdef CONFIG_IPV6_ROUTE_INFO
6943 	{
6944 		.procname	= "accept_ra_rt_info_min_plen",
6945 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6946 		.maxlen		= sizeof(int),
6947 		.mode		= 0644,
6948 		.proc_handler	= proc_dointvec,
6949 	},
6950 	{
6951 		.procname	= "accept_ra_rt_info_max_plen",
6952 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6953 		.maxlen		= sizeof(int),
6954 		.mode		= 0644,
6955 		.proc_handler	= proc_dointvec,
6956 	},
6957 #endif
6958 #endif
6959 	{
6960 		.procname	= "proxy_ndp",
6961 		.data		= &ipv6_devconf.proxy_ndp,
6962 		.maxlen		= sizeof(int),
6963 		.mode		= 0644,
6964 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6965 	},
6966 	{
6967 		.procname	= "accept_source_route",
6968 		.data		= &ipv6_devconf.accept_source_route,
6969 		.maxlen		= sizeof(int),
6970 		.mode		= 0644,
6971 		.proc_handler	= proc_dointvec,
6972 	},
6973 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
6974 	{
6975 		.procname	= "optimistic_dad",
6976 		.data		= &ipv6_devconf.optimistic_dad,
6977 		.maxlen		= sizeof(int),
6978 		.mode		= 0644,
6979 		.proc_handler   = proc_dointvec,
6980 	},
6981 	{
6982 		.procname	= "use_optimistic",
6983 		.data		= &ipv6_devconf.use_optimistic,
6984 		.maxlen		= sizeof(int),
6985 		.mode		= 0644,
6986 		.proc_handler	= proc_dointvec,
6987 	},
6988 #endif
6989 #ifdef CONFIG_IPV6_MROUTE
6990 	{
6991 		.procname	= "mc_forwarding",
6992 		.data		= &ipv6_devconf.mc_forwarding,
6993 		.maxlen		= sizeof(int),
6994 		.mode		= 0444,
6995 		.proc_handler	= proc_dointvec,
6996 	},
6997 #endif
6998 	{
6999 		.procname	= "disable_ipv6",
7000 		.data		= &ipv6_devconf.disable_ipv6,
7001 		.maxlen		= sizeof(int),
7002 		.mode		= 0644,
7003 		.proc_handler	= addrconf_sysctl_disable,
7004 	},
7005 	{
7006 		.procname	= "accept_dad",
7007 		.data		= &ipv6_devconf.accept_dad,
7008 		.maxlen		= sizeof(int),
7009 		.mode		= 0644,
7010 		.proc_handler	= proc_dointvec,
7011 	},
7012 	{
7013 		.procname	= "force_tllao",
7014 		.data		= &ipv6_devconf.force_tllao,
7015 		.maxlen		= sizeof(int),
7016 		.mode		= 0644,
7017 		.proc_handler	= proc_dointvec
7018 	},
7019 	{
7020 		.procname	= "ndisc_notify",
7021 		.data		= &ipv6_devconf.ndisc_notify,
7022 		.maxlen		= sizeof(int),
7023 		.mode		= 0644,
7024 		.proc_handler	= proc_dointvec
7025 	},
7026 	{
7027 		.procname	= "suppress_frag_ndisc",
7028 		.data		= &ipv6_devconf.suppress_frag_ndisc,
7029 		.maxlen		= sizeof(int),
7030 		.mode		= 0644,
7031 		.proc_handler	= proc_dointvec
7032 	},
7033 	{
7034 		.procname	= "accept_ra_from_local",
7035 		.data		= &ipv6_devconf.accept_ra_from_local,
7036 		.maxlen		= sizeof(int),
7037 		.mode		= 0644,
7038 		.proc_handler	= proc_dointvec,
7039 	},
7040 	{
7041 		.procname	= "accept_ra_mtu",
7042 		.data		= &ipv6_devconf.accept_ra_mtu,
7043 		.maxlen		= sizeof(int),
7044 		.mode		= 0644,
7045 		.proc_handler	= proc_dointvec,
7046 	},
7047 	{
7048 		.procname	= "stable_secret",
7049 		.data		= &ipv6_devconf.stable_secret,
7050 		.maxlen		= IPV6_MAX_STRLEN,
7051 		.mode		= 0600,
7052 		.proc_handler	= addrconf_sysctl_stable_secret,
7053 	},
7054 	{
7055 		.procname	= "use_oif_addrs_only",
7056 		.data		= &ipv6_devconf.use_oif_addrs_only,
7057 		.maxlen		= sizeof(int),
7058 		.mode		= 0644,
7059 		.proc_handler	= proc_dointvec,
7060 	},
7061 	{
7062 		.procname	= "ignore_routes_with_linkdown",
7063 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
7064 		.maxlen		= sizeof(int),
7065 		.mode		= 0644,
7066 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
7067 	},
7068 	{
7069 		.procname	= "drop_unicast_in_l2_multicast",
7070 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
7071 		.maxlen		= sizeof(int),
7072 		.mode		= 0644,
7073 		.proc_handler	= proc_dointvec,
7074 	},
7075 	{
7076 		.procname	= "drop_unsolicited_na",
7077 		.data		= &ipv6_devconf.drop_unsolicited_na,
7078 		.maxlen		= sizeof(int),
7079 		.mode		= 0644,
7080 		.proc_handler	= proc_dointvec,
7081 	},
7082 	{
7083 		.procname	= "keep_addr_on_down",
7084 		.data		= &ipv6_devconf.keep_addr_on_down,
7085 		.maxlen		= sizeof(int),
7086 		.mode		= 0644,
7087 		.proc_handler	= proc_dointvec,
7088 
7089 	},
7090 	{
7091 		.procname	= "seg6_enabled",
7092 		.data		= &ipv6_devconf.seg6_enabled,
7093 		.maxlen		= sizeof(int),
7094 		.mode		= 0644,
7095 		.proc_handler	= proc_dointvec,
7096 	},
7097 #ifdef CONFIG_IPV6_SEG6_HMAC
7098 	{
7099 		.procname	= "seg6_require_hmac",
7100 		.data		= &ipv6_devconf.seg6_require_hmac,
7101 		.maxlen		= sizeof(int),
7102 		.mode		= 0644,
7103 		.proc_handler	= proc_dointvec,
7104 	},
7105 #endif
7106 	{
7107 		.procname       = "enhanced_dad",
7108 		.data           = &ipv6_devconf.enhanced_dad,
7109 		.maxlen         = sizeof(int),
7110 		.mode           = 0644,
7111 		.proc_handler   = proc_dointvec,
7112 	},
7113 	{
7114 		.procname	= "addr_gen_mode",
7115 		.data		= &ipv6_devconf.addr_gen_mode,
7116 		.maxlen		= sizeof(int),
7117 		.mode		= 0644,
7118 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
7119 	},
7120 	{
7121 		.procname       = "disable_policy",
7122 		.data           = &ipv6_devconf.disable_policy,
7123 		.maxlen         = sizeof(int),
7124 		.mode           = 0644,
7125 		.proc_handler   = addrconf_sysctl_disable_policy,
7126 	},
7127 	{
7128 		.procname	= "ndisc_tclass",
7129 		.data		= &ipv6_devconf.ndisc_tclass,
7130 		.maxlen		= sizeof(int),
7131 		.mode		= 0644,
7132 		.proc_handler	= proc_dointvec_minmax,
7133 		.extra1		= (void *)SYSCTL_ZERO,
7134 		.extra2		= (void *)&two_five_five,
7135 	},
7136 	{
7137 		.procname	= "rpl_seg_enabled",
7138 		.data		= &ipv6_devconf.rpl_seg_enabled,
7139 		.maxlen		= sizeof(int),
7140 		.mode		= 0644,
7141 		.proc_handler	= proc_dointvec,
7142 	},
7143 	{
7144 		.procname	= "ioam6_enabled",
7145 		.data		= &ipv6_devconf.ioam6_enabled,
7146 		.maxlen		= sizeof(u8),
7147 		.mode		= 0644,
7148 		.proc_handler	= proc_dou8vec_minmax,
7149 		.extra1		= (void *)SYSCTL_ZERO,
7150 		.extra2		= (void *)SYSCTL_ONE,
7151 	},
7152 	{
7153 		.procname	= "ioam6_id",
7154 		.data		= &ipv6_devconf.ioam6_id,
7155 		.maxlen		= sizeof(u32),
7156 		.mode		= 0644,
7157 		.proc_handler	= proc_douintvec_minmax,
7158 		.extra1		= (void *)SYSCTL_ZERO,
7159 		.extra2		= (void *)&ioam6_if_id_max,
7160 	},
7161 	{
7162 		.procname	= "ioam6_id_wide",
7163 		.data		= &ipv6_devconf.ioam6_id_wide,
7164 		.maxlen		= sizeof(u32),
7165 		.mode		= 0644,
7166 		.proc_handler	= proc_douintvec,
7167 	},
7168 	{
7169 		.procname	= "ndisc_evict_nocarrier",
7170 		.data		= &ipv6_devconf.ndisc_evict_nocarrier,
7171 		.maxlen		= sizeof(u8),
7172 		.mode		= 0644,
7173 		.proc_handler	= proc_dou8vec_minmax,
7174 		.extra1		= (void *)SYSCTL_ZERO,
7175 		.extra2		= (void *)SYSCTL_ONE,
7176 	},
7177 	{
7178 		.procname	= "accept_untracked_na",
7179 		.data		= &ipv6_devconf.accept_untracked_na,
7180 		.maxlen		= sizeof(int),
7181 		.mode		= 0644,
7182 		.proc_handler	= proc_dointvec_minmax,
7183 		.extra1		= SYSCTL_ZERO,
7184 		.extra2		= SYSCTL_TWO,
7185 	},
7186 	{
7187 		/* sentinel */
7188 	}
7189 };
7190 
7191 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
7192 		struct inet6_dev *idev, struct ipv6_devconf *p)
7193 {
7194 	int i, ifindex;
7195 	struct ctl_table *table;
7196 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
7197 
7198 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL_ACCOUNT);
7199 	if (!table)
7200 		goto out;
7201 
7202 	for (i = 0; table[i].data; i++) {
7203 		table[i].data += (char *)p - (char *)&ipv6_devconf;
7204 		/* If one of these is already set, then it is not safe to
7205 		 * overwrite either of them: this makes proc_dointvec_minmax
7206 		 * usable.
7207 		 */
7208 		if (!table[i].extra1 && !table[i].extra2) {
7209 			table[i].extra1 = idev; /* embedded; no ref */
7210 			table[i].extra2 = net;
7211 		}
7212 	}
7213 
7214 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
7215 
7216 	p->sysctl_header = register_net_sysctl_sz(net, path, table,
7217 						  ARRAY_SIZE(addrconf_sysctl));
7218 	if (!p->sysctl_header)
7219 		goto free;
7220 
7221 	if (!strcmp(dev_name, "all"))
7222 		ifindex = NETCONFA_IFINDEX_ALL;
7223 	else if (!strcmp(dev_name, "default"))
7224 		ifindex = NETCONFA_IFINDEX_DEFAULT;
7225 	else
7226 		ifindex = idev->dev->ifindex;
7227 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
7228 				     ifindex, p);
7229 	return 0;
7230 
7231 free:
7232 	kfree(table);
7233 out:
7234 	return -ENOBUFS;
7235 }
7236 
7237 static void __addrconf_sysctl_unregister(struct net *net,
7238 					 struct ipv6_devconf *p, int ifindex)
7239 {
7240 	struct ctl_table *table;
7241 
7242 	if (!p->sysctl_header)
7243 		return;
7244 
7245 	table = p->sysctl_header->ctl_table_arg;
7246 	unregister_net_sysctl_table(p->sysctl_header);
7247 	p->sysctl_header = NULL;
7248 	kfree(table);
7249 
7250 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
7251 }
7252 
7253 static int addrconf_sysctl_register(struct inet6_dev *idev)
7254 {
7255 	int err;
7256 
7257 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
7258 		return -EINVAL;
7259 
7260 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
7261 				    &ndisc_ifinfo_sysctl_change);
7262 	if (err)
7263 		return err;
7264 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
7265 					 idev, &idev->cnf);
7266 	if (err)
7267 		neigh_sysctl_unregister(idev->nd_parms);
7268 
7269 	return err;
7270 }
7271 
7272 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
7273 {
7274 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
7275 				     idev->dev->ifindex);
7276 	neigh_sysctl_unregister(idev->nd_parms);
7277 }
7278 
7279 
7280 #endif
7281 
7282 static int __net_init addrconf_init_net(struct net *net)
7283 {
7284 	int err = -ENOMEM;
7285 	struct ipv6_devconf *all, *dflt;
7286 
7287 	spin_lock_init(&net->ipv6.addrconf_hash_lock);
7288 	INIT_DEFERRABLE_WORK(&net->ipv6.addr_chk_work, addrconf_verify_work);
7289 	net->ipv6.inet6_addr_lst = kcalloc(IN6_ADDR_HSIZE,
7290 					   sizeof(struct hlist_head),
7291 					   GFP_KERNEL);
7292 	if (!net->ipv6.inet6_addr_lst)
7293 		goto err_alloc_addr;
7294 
7295 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
7296 	if (!all)
7297 		goto err_alloc_all;
7298 
7299 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
7300 	if (!dflt)
7301 		goto err_alloc_dflt;
7302 
7303 	if (!net_eq(net, &init_net)) {
7304 		switch (net_inherit_devconf()) {
7305 		case 1:  /* copy from init_net */
7306 			memcpy(all, init_net.ipv6.devconf_all,
7307 			       sizeof(ipv6_devconf));
7308 			memcpy(dflt, init_net.ipv6.devconf_dflt,
7309 			       sizeof(ipv6_devconf_dflt));
7310 			break;
7311 		case 3: /* copy from the current netns */
7312 			memcpy(all, current->nsproxy->net_ns->ipv6.devconf_all,
7313 			       sizeof(ipv6_devconf));
7314 			memcpy(dflt,
7315 			       current->nsproxy->net_ns->ipv6.devconf_dflt,
7316 			       sizeof(ipv6_devconf_dflt));
7317 			break;
7318 		case 0:
7319 		case 2:
7320 			/* use compiled values */
7321 			break;
7322 		}
7323 	}
7324 
7325 	/* these will be inherited by all namespaces */
7326 	dflt->autoconf = ipv6_defaults.autoconf;
7327 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
7328 
7329 	dflt->stable_secret.initialized = false;
7330 	all->stable_secret.initialized = false;
7331 
7332 	net->ipv6.devconf_all = all;
7333 	net->ipv6.devconf_dflt = dflt;
7334 
7335 #ifdef CONFIG_SYSCTL
7336 	err = __addrconf_sysctl_register(net, "all", NULL, all);
7337 	if (err < 0)
7338 		goto err_reg_all;
7339 
7340 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
7341 	if (err < 0)
7342 		goto err_reg_dflt;
7343 #endif
7344 	return 0;
7345 
7346 #ifdef CONFIG_SYSCTL
7347 err_reg_dflt:
7348 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
7349 err_reg_all:
7350 	kfree(dflt);
7351 	net->ipv6.devconf_dflt = NULL;
7352 #endif
7353 err_alloc_dflt:
7354 	kfree(all);
7355 	net->ipv6.devconf_all = NULL;
7356 err_alloc_all:
7357 	kfree(net->ipv6.inet6_addr_lst);
7358 err_alloc_addr:
7359 	return err;
7360 }
7361 
7362 static void __net_exit addrconf_exit_net(struct net *net)
7363 {
7364 	int i;
7365 
7366 #ifdef CONFIG_SYSCTL
7367 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
7368 				     NETCONFA_IFINDEX_DEFAULT);
7369 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
7370 				     NETCONFA_IFINDEX_ALL);
7371 #endif
7372 	kfree(net->ipv6.devconf_dflt);
7373 	net->ipv6.devconf_dflt = NULL;
7374 	kfree(net->ipv6.devconf_all);
7375 	net->ipv6.devconf_all = NULL;
7376 
7377 	cancel_delayed_work_sync(&net->ipv6.addr_chk_work);
7378 	/*
7379 	 *	Check hash table, then free it.
7380 	 */
7381 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7382 		WARN_ON_ONCE(!hlist_empty(&net->ipv6.inet6_addr_lst[i]));
7383 
7384 	kfree(net->ipv6.inet6_addr_lst);
7385 	net->ipv6.inet6_addr_lst = NULL;
7386 }
7387 
7388 static struct pernet_operations addrconf_ops = {
7389 	.init = addrconf_init_net,
7390 	.exit = addrconf_exit_net,
7391 };
7392 
7393 static struct rtnl_af_ops inet6_ops __read_mostly = {
7394 	.family		  = AF_INET6,
7395 	.fill_link_af	  = inet6_fill_link_af,
7396 	.get_link_af_size = inet6_get_link_af_size,
7397 	.validate_link_af = inet6_validate_link_af,
7398 	.set_link_af	  = inet6_set_link_af,
7399 };
7400 
7401 /*
7402  *	Init / cleanup code
7403  */
7404 
7405 int __init addrconf_init(void)
7406 {
7407 	struct inet6_dev *idev;
7408 	int err;
7409 
7410 	err = ipv6_addr_label_init();
7411 	if (err < 0) {
7412 		pr_crit("%s: cannot initialize default policy table: %d\n",
7413 			__func__, err);
7414 		goto out;
7415 	}
7416 
7417 	err = register_pernet_subsys(&addrconf_ops);
7418 	if (err < 0)
7419 		goto out_addrlabel;
7420 
7421 	/* All works using addrconf_wq need to lock rtnl. */
7422 	addrconf_wq = create_singlethread_workqueue("ipv6_addrconf");
7423 	if (!addrconf_wq) {
7424 		err = -ENOMEM;
7425 		goto out_nowq;
7426 	}
7427 
7428 	rtnl_lock();
7429 	idev = ipv6_add_dev(blackhole_netdev);
7430 	rtnl_unlock();
7431 	if (IS_ERR(idev)) {
7432 		err = PTR_ERR(idev);
7433 		goto errlo;
7434 	}
7435 
7436 	ip6_route_init_special_entries();
7437 
7438 	register_netdevice_notifier(&ipv6_dev_notf);
7439 
7440 	addrconf_verify(&init_net);
7441 
7442 	rtnl_af_register(&inet6_ops);
7443 
7444 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETLINK,
7445 				   NULL, inet6_dump_ifinfo, RTNL_FLAG_DUMP_UNLOCKED);
7446 	if (err < 0)
7447 		goto errout;
7448 
7449 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWADDR,
7450 				   inet6_rtm_newaddr, NULL, 0);
7451 	if (err < 0)
7452 		goto errout;
7453 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELADDR,
7454 				   inet6_rtm_deladdr, NULL, 0);
7455 	if (err < 0)
7456 		goto errout;
7457 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDR,
7458 				   inet6_rtm_getaddr, inet6_dump_ifaddr,
7459 				   RTNL_FLAG_DOIT_UNLOCKED |
7460 				   RTNL_FLAG_DUMP_UNLOCKED);
7461 	if (err < 0)
7462 		goto errout;
7463 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETMULTICAST,
7464 				   NULL, inet6_dump_ifmcaddr,
7465 				   RTNL_FLAG_DUMP_UNLOCKED);
7466 	if (err < 0)
7467 		goto errout;
7468 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETANYCAST,
7469 				   NULL, inet6_dump_ifacaddr,
7470 				   RTNL_FLAG_DUMP_UNLOCKED);
7471 	if (err < 0)
7472 		goto errout;
7473 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETNETCONF,
7474 				   inet6_netconf_get_devconf,
7475 				   inet6_netconf_dump_devconf,
7476 				   RTNL_FLAG_DOIT_UNLOCKED |
7477 				   RTNL_FLAG_DUMP_UNLOCKED);
7478 	if (err < 0)
7479 		goto errout;
7480 	err = ipv6_addr_label_rtnl_register();
7481 	if (err < 0)
7482 		goto errout;
7483 
7484 	return 0;
7485 errout:
7486 	rtnl_unregister_all(PF_INET6);
7487 	rtnl_af_unregister(&inet6_ops);
7488 	unregister_netdevice_notifier(&ipv6_dev_notf);
7489 errlo:
7490 	destroy_workqueue(addrconf_wq);
7491 out_nowq:
7492 	unregister_pernet_subsys(&addrconf_ops);
7493 out_addrlabel:
7494 	ipv6_addr_label_cleanup();
7495 out:
7496 	return err;
7497 }
7498 
7499 void addrconf_cleanup(void)
7500 {
7501 	struct net_device *dev;
7502 
7503 	unregister_netdevice_notifier(&ipv6_dev_notf);
7504 	unregister_pernet_subsys(&addrconf_ops);
7505 	ipv6_addr_label_cleanup();
7506 
7507 	rtnl_af_unregister(&inet6_ops);
7508 
7509 	rtnl_lock();
7510 
7511 	/* clean dev list */
7512 	for_each_netdev(&init_net, dev) {
7513 		if (__in6_dev_get(dev) == NULL)
7514 			continue;
7515 		addrconf_ifdown(dev, true);
7516 	}
7517 	addrconf_ifdown(init_net.loopback_dev, true);
7518 
7519 	rtnl_unlock();
7520 
7521 	destroy_workqueue(addrconf_wq);
7522 }
7523