xref: /linux/net/ipv6/addrconf.c (revision 1553a1c48281243359a9529a10ddb551f3b967ab)
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 				result = ifp;
2095 				in6_ifa_hold(ifp);
2096 				break;
2097 			}
2098 		}
2099 	}
2100 	rcu_read_unlock();
2101 
2102 	return result;
2103 }
2104 
2105 /* Gets referenced address, destroys ifaddr */
2106 
2107 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
2108 {
2109 	if (dad_failed)
2110 		ifp->flags |= IFA_F_DADFAILED;
2111 
2112 	if (ifp->flags&IFA_F_TEMPORARY) {
2113 		struct inet6_ifaddr *ifpub;
2114 		spin_lock_bh(&ifp->lock);
2115 		ifpub = ifp->ifpub;
2116 		if (ifpub) {
2117 			in6_ifa_hold(ifpub);
2118 			spin_unlock_bh(&ifp->lock);
2119 			ipv6_create_tempaddr(ifpub, true);
2120 			in6_ifa_put(ifpub);
2121 		} else {
2122 			spin_unlock_bh(&ifp->lock);
2123 		}
2124 		ipv6_del_addr(ifp);
2125 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
2126 		spin_lock_bh(&ifp->lock);
2127 		addrconf_del_dad_work(ifp);
2128 		ifp->flags |= IFA_F_TENTATIVE;
2129 		if (dad_failed)
2130 			ifp->flags &= ~IFA_F_OPTIMISTIC;
2131 		spin_unlock_bh(&ifp->lock);
2132 		if (dad_failed)
2133 			ipv6_ifa_notify(0, ifp);
2134 		in6_ifa_put(ifp);
2135 	} else {
2136 		ipv6_del_addr(ifp);
2137 	}
2138 }
2139 
2140 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
2141 {
2142 	int err = -ENOENT;
2143 
2144 	spin_lock_bh(&ifp->lock);
2145 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
2146 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
2147 		err = 0;
2148 	}
2149 	spin_unlock_bh(&ifp->lock);
2150 
2151 	return err;
2152 }
2153 
2154 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp)
2155 {
2156 	struct inet6_dev *idev = ifp->idev;
2157 	struct net *net = dev_net(idev->dev);
2158 	int max_addresses;
2159 
2160 	if (addrconf_dad_end(ifp)) {
2161 		in6_ifa_put(ifp);
2162 		return;
2163 	}
2164 
2165 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c used by %pM detected!\n",
2166 			     ifp->idev->dev->name, &ifp->addr, eth_hdr(skb)->h_source);
2167 
2168 	spin_lock_bh(&ifp->lock);
2169 
2170 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2171 		struct in6_addr new_addr;
2172 		struct inet6_ifaddr *ifp2;
2173 		int retries = ifp->stable_privacy_retry + 1;
2174 		struct ifa6_config cfg = {
2175 			.pfx = &new_addr,
2176 			.plen = ifp->prefix_len,
2177 			.ifa_flags = ifp->flags,
2178 			.valid_lft = ifp->valid_lft,
2179 			.preferred_lft = ifp->prefered_lft,
2180 			.scope = ifp->scope,
2181 		};
2182 
2183 		if (retries > net->ipv6.sysctl.idgen_retries) {
2184 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2185 					     ifp->idev->dev->name);
2186 			goto errdad;
2187 		}
2188 
2189 		new_addr = ifp->addr;
2190 		if (ipv6_generate_stable_address(&new_addr, retries,
2191 						 idev))
2192 			goto errdad;
2193 
2194 		spin_unlock_bh(&ifp->lock);
2195 
2196 		max_addresses = READ_ONCE(idev->cnf.max_addresses);
2197 		if (max_addresses &&
2198 		    ipv6_count_addresses(idev) >= max_addresses)
2199 			goto lock_errdad;
2200 
2201 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2202 				     ifp->idev->dev->name);
2203 
2204 		ifp2 = ipv6_add_addr(idev, &cfg, false, NULL);
2205 		if (IS_ERR(ifp2))
2206 			goto lock_errdad;
2207 
2208 		spin_lock_bh(&ifp2->lock);
2209 		ifp2->stable_privacy_retry = retries;
2210 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2211 		spin_unlock_bh(&ifp2->lock);
2212 
2213 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2214 		in6_ifa_put(ifp2);
2215 lock_errdad:
2216 		spin_lock_bh(&ifp->lock);
2217 	}
2218 
2219 errdad:
2220 	/* transition from _POSTDAD to _ERRDAD */
2221 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2222 	spin_unlock_bh(&ifp->lock);
2223 
2224 	addrconf_mod_dad_work(ifp, 0);
2225 	in6_ifa_put(ifp);
2226 }
2227 
2228 /* Join to solicited addr multicast group.
2229  * caller must hold RTNL */
2230 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2231 {
2232 	struct in6_addr maddr;
2233 
2234 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2235 		return;
2236 
2237 	addrconf_addr_solict_mult(addr, &maddr);
2238 	ipv6_dev_mc_inc(dev, &maddr);
2239 }
2240 
2241 /* caller must hold RTNL */
2242 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2243 {
2244 	struct in6_addr maddr;
2245 
2246 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2247 		return;
2248 
2249 	addrconf_addr_solict_mult(addr, &maddr);
2250 	__ipv6_dev_mc_dec(idev, &maddr);
2251 }
2252 
2253 /* caller must hold RTNL */
2254 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2255 {
2256 	struct in6_addr addr;
2257 
2258 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2259 		return;
2260 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2261 	if (ipv6_addr_any(&addr))
2262 		return;
2263 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2264 }
2265 
2266 /* caller must hold RTNL */
2267 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2268 {
2269 	struct in6_addr addr;
2270 
2271 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2272 		return;
2273 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2274 	if (ipv6_addr_any(&addr))
2275 		return;
2276 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2277 }
2278 
2279 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2280 {
2281 	switch (dev->addr_len) {
2282 	case ETH_ALEN:
2283 		memcpy(eui, dev->dev_addr, 3);
2284 		eui[3] = 0xFF;
2285 		eui[4] = 0xFE;
2286 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2287 		break;
2288 	case EUI64_ADDR_LEN:
2289 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2290 		eui[0] ^= 2;
2291 		break;
2292 	default:
2293 		return -1;
2294 	}
2295 
2296 	return 0;
2297 }
2298 
2299 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2300 {
2301 	const union fwnet_hwaddr *ha;
2302 
2303 	if (dev->addr_len != FWNET_ALEN)
2304 		return -1;
2305 
2306 	ha = (const union fwnet_hwaddr *)dev->dev_addr;
2307 
2308 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2309 	eui[0] ^= 2;
2310 	return 0;
2311 }
2312 
2313 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2314 {
2315 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2316 	if (dev->addr_len != ARCNET_ALEN)
2317 		return -1;
2318 	memset(eui, 0, 7);
2319 	eui[7] = *(u8 *)dev->dev_addr;
2320 	return 0;
2321 }
2322 
2323 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2324 {
2325 	if (dev->addr_len != INFINIBAND_ALEN)
2326 		return -1;
2327 	memcpy(eui, dev->dev_addr + 12, 8);
2328 	eui[0] |= 2;
2329 	return 0;
2330 }
2331 
2332 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2333 {
2334 	if (addr == 0)
2335 		return -1;
2336 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2337 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2338 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2339 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2340 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2341 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2342 	eui[1] = 0;
2343 	eui[2] = 0x5E;
2344 	eui[3] = 0xFE;
2345 	memcpy(eui + 4, &addr, 4);
2346 	return 0;
2347 }
2348 
2349 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2350 {
2351 	if (dev->priv_flags & IFF_ISATAP)
2352 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2353 	return -1;
2354 }
2355 
2356 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2357 {
2358 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2359 }
2360 
2361 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2362 {
2363 	memcpy(eui, dev->perm_addr, 3);
2364 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2365 	eui[3] = 0xFF;
2366 	eui[4] = 0xFE;
2367 	eui[0] ^= 2;
2368 	return 0;
2369 }
2370 
2371 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2372 {
2373 	switch (dev->type) {
2374 	case ARPHRD_ETHER:
2375 	case ARPHRD_FDDI:
2376 		return addrconf_ifid_eui48(eui, dev);
2377 	case ARPHRD_ARCNET:
2378 		return addrconf_ifid_arcnet(eui, dev);
2379 	case ARPHRD_INFINIBAND:
2380 		return addrconf_ifid_infiniband(eui, dev);
2381 	case ARPHRD_SIT:
2382 		return addrconf_ifid_sit(eui, dev);
2383 	case ARPHRD_IPGRE:
2384 	case ARPHRD_TUNNEL:
2385 		return addrconf_ifid_gre(eui, dev);
2386 	case ARPHRD_6LOWPAN:
2387 		return addrconf_ifid_6lowpan(eui, dev);
2388 	case ARPHRD_IEEE1394:
2389 		return addrconf_ifid_ieee1394(eui, dev);
2390 	case ARPHRD_TUNNEL6:
2391 	case ARPHRD_IP6GRE:
2392 	case ARPHRD_RAWIP:
2393 		return addrconf_ifid_ip6tnl(eui, dev);
2394 	}
2395 	return -1;
2396 }
2397 
2398 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2399 {
2400 	int err = -1;
2401 	struct inet6_ifaddr *ifp;
2402 
2403 	read_lock_bh(&idev->lock);
2404 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2405 		if (ifp->scope > IFA_LINK)
2406 			break;
2407 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2408 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2409 			err = 0;
2410 			break;
2411 		}
2412 	}
2413 	read_unlock_bh(&idev->lock);
2414 	return err;
2415 }
2416 
2417 /* Generation of a randomized Interface Identifier
2418  * draft-ietf-6man-rfc4941bis, Section 3.3.1
2419  */
2420 
2421 static void ipv6_gen_rnd_iid(struct in6_addr *addr)
2422 {
2423 regen:
2424 	get_random_bytes(&addr->s6_addr[8], 8);
2425 
2426 	/* <draft-ietf-6man-rfc4941bis-08.txt>, Section 3.3.1:
2427 	 * check if generated address is not inappropriate:
2428 	 *
2429 	 * - Reserved IPv6 Interface Identifiers
2430 	 * - XXX: already assigned to an address on the device
2431 	 */
2432 
2433 	/* Subnet-router anycast: 0000:0000:0000:0000 */
2434 	if (!(addr->s6_addr32[2] | addr->s6_addr32[3]))
2435 		goto regen;
2436 
2437 	/* IANA Ethernet block: 0200:5EFF:FE00:0000-0200:5EFF:FE00:5212
2438 	 * Proxy Mobile IPv6:   0200:5EFF:FE00:5213
2439 	 * IANA Ethernet block: 0200:5EFF:FE00:5214-0200:5EFF:FEFF:FFFF
2440 	 */
2441 	if (ntohl(addr->s6_addr32[2]) == 0x02005eff &&
2442 	    (ntohl(addr->s6_addr32[3]) & 0Xff000000) == 0xfe000000)
2443 		goto regen;
2444 
2445 	/* Reserved subnet anycast addresses */
2446 	if (ntohl(addr->s6_addr32[2]) == 0xfdffffff &&
2447 	    ntohl(addr->s6_addr32[3]) >= 0Xffffff80)
2448 		goto regen;
2449 }
2450 
2451 /*
2452  *	Add prefix route.
2453  */
2454 
2455 static void
2456 addrconf_prefix_route(struct in6_addr *pfx, int plen, u32 metric,
2457 		      struct net_device *dev, unsigned long expires,
2458 		      u32 flags, gfp_t gfp_flags)
2459 {
2460 	struct fib6_config cfg = {
2461 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2462 		.fc_metric = metric ? : IP6_RT_PRIO_ADDRCONF,
2463 		.fc_ifindex = dev->ifindex,
2464 		.fc_expires = expires,
2465 		.fc_dst_len = plen,
2466 		.fc_flags = RTF_UP | flags,
2467 		.fc_nlinfo.nl_net = dev_net(dev),
2468 		.fc_protocol = RTPROT_KERNEL,
2469 		.fc_type = RTN_UNICAST,
2470 	};
2471 
2472 	cfg.fc_dst = *pfx;
2473 
2474 	/* Prevent useless cloning on PtP SIT.
2475 	   This thing is done here expecting that the whole
2476 	   class of non-broadcast devices need not cloning.
2477 	 */
2478 #if IS_ENABLED(CONFIG_IPV6_SIT)
2479 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2480 		cfg.fc_flags |= RTF_NONEXTHOP;
2481 #endif
2482 
2483 	ip6_route_add(&cfg, gfp_flags, NULL);
2484 }
2485 
2486 
2487 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2488 						  int plen,
2489 						  const struct net_device *dev,
2490 						  u32 flags, u32 noflags,
2491 						  bool no_gw)
2492 {
2493 	struct fib6_node *fn;
2494 	struct fib6_info *rt = NULL;
2495 	struct fib6_table *table;
2496 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2497 
2498 	table = fib6_get_table(dev_net(dev), tb_id);
2499 	if (!table)
2500 		return NULL;
2501 
2502 	rcu_read_lock();
2503 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2504 	if (!fn)
2505 		goto out;
2506 
2507 	for_each_fib6_node_rt_rcu(fn) {
2508 		/* prefix routes only use builtin fib6_nh */
2509 		if (rt->nh)
2510 			continue;
2511 
2512 		if (rt->fib6_nh->fib_nh_dev->ifindex != dev->ifindex)
2513 			continue;
2514 		if (no_gw && rt->fib6_nh->fib_nh_gw_family)
2515 			continue;
2516 		if ((rt->fib6_flags & flags) != flags)
2517 			continue;
2518 		if ((rt->fib6_flags & noflags) != 0)
2519 			continue;
2520 		if (!fib6_info_hold_safe(rt))
2521 			continue;
2522 		break;
2523 	}
2524 out:
2525 	rcu_read_unlock();
2526 	return rt;
2527 }
2528 
2529 
2530 /* Create "default" multicast route to the interface */
2531 
2532 static void addrconf_add_mroute(struct net_device *dev)
2533 {
2534 	struct fib6_config cfg = {
2535 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2536 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2537 		.fc_ifindex = dev->ifindex,
2538 		.fc_dst_len = 8,
2539 		.fc_flags = RTF_UP,
2540 		.fc_type = RTN_MULTICAST,
2541 		.fc_nlinfo.nl_net = dev_net(dev),
2542 		.fc_protocol = RTPROT_KERNEL,
2543 	};
2544 
2545 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2546 
2547 	ip6_route_add(&cfg, GFP_KERNEL, NULL);
2548 }
2549 
2550 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2551 {
2552 	struct inet6_dev *idev;
2553 
2554 	ASSERT_RTNL();
2555 
2556 	idev = ipv6_find_idev(dev);
2557 	if (IS_ERR(idev))
2558 		return idev;
2559 
2560 	if (idev->cnf.disable_ipv6)
2561 		return ERR_PTR(-EACCES);
2562 
2563 	/* Add default multicast route */
2564 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2565 		addrconf_add_mroute(dev);
2566 
2567 	return idev;
2568 }
2569 
2570 static void manage_tempaddrs(struct inet6_dev *idev,
2571 			     struct inet6_ifaddr *ifp,
2572 			     __u32 valid_lft, __u32 prefered_lft,
2573 			     bool create, unsigned long now)
2574 {
2575 	u32 flags;
2576 	struct inet6_ifaddr *ift;
2577 
2578 	read_lock_bh(&idev->lock);
2579 	/* update all temporary addresses in the list */
2580 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2581 		int age, max_valid, max_prefered;
2582 
2583 		if (ifp != ift->ifpub)
2584 			continue;
2585 
2586 		/* RFC 4941 section 3.3:
2587 		 * If a received option will extend the lifetime of a public
2588 		 * address, the lifetimes of temporary addresses should
2589 		 * be extended, subject to the overall constraint that no
2590 		 * temporary addresses should ever remain "valid" or "preferred"
2591 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2592 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2593 		 */
2594 		age = (now - ift->cstamp) / HZ;
2595 		max_valid = READ_ONCE(idev->cnf.temp_valid_lft) - age;
2596 		if (max_valid < 0)
2597 			max_valid = 0;
2598 
2599 		max_prefered = READ_ONCE(idev->cnf.temp_prefered_lft) -
2600 			       idev->desync_factor - age;
2601 		if (max_prefered < 0)
2602 			max_prefered = 0;
2603 
2604 		if (valid_lft > max_valid)
2605 			valid_lft = max_valid;
2606 
2607 		if (prefered_lft > max_prefered)
2608 			prefered_lft = max_prefered;
2609 
2610 		spin_lock(&ift->lock);
2611 		flags = ift->flags;
2612 		ift->valid_lft = valid_lft;
2613 		ift->prefered_lft = prefered_lft;
2614 		ift->tstamp = now;
2615 		if (prefered_lft > 0)
2616 			ift->flags &= ~IFA_F_DEPRECATED;
2617 
2618 		spin_unlock(&ift->lock);
2619 		if (!(flags&IFA_F_TENTATIVE))
2620 			ipv6_ifa_notify(0, ift);
2621 	}
2622 
2623 	/* Also create a temporary address if it's enabled but no temporary
2624 	 * address currently exists.
2625 	 * However, we get called with valid_lft == 0, prefered_lft == 0, create == false
2626 	 * as part of cleanup (ie. deleting the mngtmpaddr).
2627 	 * We don't want that to result in creating a new temporary ip address.
2628 	 */
2629 	if (list_empty(&idev->tempaddr_list) && (valid_lft || prefered_lft))
2630 		create = true;
2631 
2632 	if (create && READ_ONCE(idev->cnf.use_tempaddr) > 0) {
2633 		/* When a new public address is created as described
2634 		 * in [ADDRCONF], also create a new temporary address.
2635 		 */
2636 		read_unlock_bh(&idev->lock);
2637 		ipv6_create_tempaddr(ifp, false);
2638 	} else {
2639 		read_unlock_bh(&idev->lock);
2640 	}
2641 }
2642 
2643 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2644 {
2645 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2646 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2647 }
2648 
2649 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2650 				 const struct prefix_info *pinfo,
2651 				 struct inet6_dev *in6_dev,
2652 				 const struct in6_addr *addr, int addr_type,
2653 				 u32 addr_flags, bool sllao, bool tokenized,
2654 				 __u32 valid_lft, u32 prefered_lft)
2655 {
2656 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2657 	int create = 0, update_lft = 0;
2658 
2659 	if (!ifp && valid_lft) {
2660 		int max_addresses = READ_ONCE(in6_dev->cnf.max_addresses);
2661 		struct ifa6_config cfg = {
2662 			.pfx = addr,
2663 			.plen = pinfo->prefix_len,
2664 			.ifa_flags = addr_flags,
2665 			.valid_lft = valid_lft,
2666 			.preferred_lft = prefered_lft,
2667 			.scope = addr_type & IPV6_ADDR_SCOPE_MASK,
2668 			.ifa_proto = IFAPROT_KERNEL_RA
2669 		};
2670 
2671 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2672 		if ((READ_ONCE(net->ipv6.devconf_all->optimistic_dad) ||
2673 		     READ_ONCE(in6_dev->cnf.optimistic_dad)) &&
2674 		    !net->ipv6.devconf_all->forwarding && sllao)
2675 			cfg.ifa_flags |= IFA_F_OPTIMISTIC;
2676 #endif
2677 
2678 		/* Do not allow to create too much of autoconfigured
2679 		 * addresses; this would be too easy way to crash kernel.
2680 		 */
2681 		if (!max_addresses ||
2682 		    ipv6_count_addresses(in6_dev) < max_addresses)
2683 			ifp = ipv6_add_addr(in6_dev, &cfg, false, NULL);
2684 
2685 		if (IS_ERR_OR_NULL(ifp))
2686 			return -1;
2687 
2688 		create = 1;
2689 		spin_lock_bh(&ifp->lock);
2690 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2691 		ifp->cstamp = jiffies;
2692 		ifp->tokenized = tokenized;
2693 		spin_unlock_bh(&ifp->lock);
2694 		addrconf_dad_start(ifp);
2695 	}
2696 
2697 	if (ifp) {
2698 		u32 flags;
2699 		unsigned long now;
2700 		u32 stored_lft;
2701 
2702 		/* update lifetime (RFC2462 5.5.3 e) */
2703 		spin_lock_bh(&ifp->lock);
2704 		now = jiffies;
2705 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2706 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2707 		else
2708 			stored_lft = 0;
2709 
2710 		/* RFC4862 Section 5.5.3e:
2711 		 * "Note that the preferred lifetime of the
2712 		 *  corresponding address is always reset to
2713 		 *  the Preferred Lifetime in the received
2714 		 *  Prefix Information option, regardless of
2715 		 *  whether the valid lifetime is also reset or
2716 		 *  ignored."
2717 		 *
2718 		 * So we should always update prefered_lft here.
2719 		 */
2720 		update_lft = !create && stored_lft;
2721 
2722 		if (update_lft && !READ_ONCE(in6_dev->cnf.ra_honor_pio_life)) {
2723 			const u32 minimum_lft = min_t(u32,
2724 				stored_lft, MIN_VALID_LIFETIME);
2725 			valid_lft = max(valid_lft, minimum_lft);
2726 		}
2727 
2728 		if (update_lft) {
2729 			ifp->valid_lft = valid_lft;
2730 			ifp->prefered_lft = prefered_lft;
2731 			WRITE_ONCE(ifp->tstamp, now);
2732 			flags = ifp->flags;
2733 			ifp->flags &= ~IFA_F_DEPRECATED;
2734 			spin_unlock_bh(&ifp->lock);
2735 
2736 			if (!(flags&IFA_F_TENTATIVE))
2737 				ipv6_ifa_notify(0, ifp);
2738 		} else
2739 			spin_unlock_bh(&ifp->lock);
2740 
2741 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2742 				 create, now);
2743 
2744 		in6_ifa_put(ifp);
2745 		addrconf_verify(net);
2746 	}
2747 
2748 	return 0;
2749 }
2750 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2751 
2752 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2753 {
2754 	struct prefix_info *pinfo;
2755 	struct fib6_table *table;
2756 	__u32 valid_lft;
2757 	__u32 prefered_lft;
2758 	int addr_type, err;
2759 	u32 addr_flags = 0;
2760 	struct inet6_dev *in6_dev;
2761 	struct net *net = dev_net(dev);
2762 
2763 	pinfo = (struct prefix_info *) opt;
2764 
2765 	if (len < sizeof(struct prefix_info)) {
2766 		netdev_dbg(dev, "addrconf: prefix option too short\n");
2767 		return;
2768 	}
2769 
2770 	/*
2771 	 *	Validation checks ([ADDRCONF], page 19)
2772 	 */
2773 
2774 	addr_type = ipv6_addr_type(&pinfo->prefix);
2775 
2776 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2777 		return;
2778 
2779 	valid_lft = ntohl(pinfo->valid);
2780 	prefered_lft = ntohl(pinfo->prefered);
2781 
2782 	if (prefered_lft > valid_lft) {
2783 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2784 		return;
2785 	}
2786 
2787 	in6_dev = in6_dev_get(dev);
2788 
2789 	if (!in6_dev) {
2790 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2791 				    dev->name);
2792 		return;
2793 	}
2794 
2795 	if (valid_lft != 0 && valid_lft < in6_dev->cnf.accept_ra_min_lft)
2796 		goto put;
2797 
2798 	/*
2799 	 *	Two things going on here:
2800 	 *	1) Add routes for on-link prefixes
2801 	 *	2) Configure prefixes with the auto flag set
2802 	 */
2803 
2804 	if (pinfo->onlink) {
2805 		struct fib6_info *rt;
2806 		unsigned long rt_expires;
2807 
2808 		/* Avoid arithmetic overflow. Really, we could
2809 		 * save rt_expires in seconds, likely valid_lft,
2810 		 * but it would require division in fib gc, that it
2811 		 * not good.
2812 		 */
2813 		if (HZ > USER_HZ)
2814 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2815 		else
2816 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2817 
2818 		if (addrconf_finite_timeout(rt_expires))
2819 			rt_expires *= HZ;
2820 
2821 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2822 					       pinfo->prefix_len,
2823 					       dev,
2824 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2825 					       RTF_DEFAULT, true);
2826 
2827 		if (rt) {
2828 			/* Autoconf prefix route */
2829 			if (valid_lft == 0) {
2830 				ip6_del_rt(net, rt, false);
2831 				rt = NULL;
2832 			} else {
2833 				table = rt->fib6_table;
2834 				spin_lock_bh(&table->tb6_lock);
2835 
2836 				if (addrconf_finite_timeout(rt_expires)) {
2837 					/* not infinity */
2838 					fib6_set_expires(rt, jiffies + rt_expires);
2839 					fib6_add_gc_list(rt);
2840 				} else {
2841 					fib6_clean_expires(rt);
2842 					fib6_remove_gc_list(rt);
2843 				}
2844 
2845 				spin_unlock_bh(&table->tb6_lock);
2846 			}
2847 		} else if (valid_lft) {
2848 			clock_t expires = 0;
2849 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2850 			if (addrconf_finite_timeout(rt_expires)) {
2851 				/* not infinity */
2852 				flags |= RTF_EXPIRES;
2853 				expires = jiffies_to_clock_t(rt_expires);
2854 			}
2855 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2856 					      0, dev, expires, flags,
2857 					      GFP_ATOMIC);
2858 		}
2859 		fib6_info_release(rt);
2860 	}
2861 
2862 	/* Try to figure out our local address for this prefix */
2863 
2864 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2865 		struct in6_addr addr;
2866 		bool tokenized = false, dev_addr_generated = false;
2867 
2868 		if (pinfo->prefix_len == 64) {
2869 			memcpy(&addr, &pinfo->prefix, 8);
2870 
2871 			if (!ipv6_addr_any(&in6_dev->token)) {
2872 				read_lock_bh(&in6_dev->lock);
2873 				memcpy(addr.s6_addr + 8,
2874 				       in6_dev->token.s6_addr + 8, 8);
2875 				read_unlock_bh(&in6_dev->lock);
2876 				tokenized = true;
2877 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2878 				   !ipv6_generate_stable_address(&addr, 0,
2879 								 in6_dev)) {
2880 				addr_flags |= IFA_F_STABLE_PRIVACY;
2881 				goto ok;
2882 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2883 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2884 				goto put;
2885 			} else {
2886 				dev_addr_generated = true;
2887 			}
2888 			goto ok;
2889 		}
2890 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2891 				    pinfo->prefix_len);
2892 		goto put;
2893 
2894 ok:
2895 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2896 						   &addr, addr_type,
2897 						   addr_flags, sllao,
2898 						   tokenized, valid_lft,
2899 						   prefered_lft);
2900 		if (err)
2901 			goto put;
2902 
2903 		/* Ignore error case here because previous prefix add addr was
2904 		 * successful which will be notified.
2905 		 */
2906 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2907 					      addr_type, addr_flags, sllao,
2908 					      tokenized, valid_lft,
2909 					      prefered_lft,
2910 					      dev_addr_generated);
2911 	}
2912 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2913 put:
2914 	in6_dev_put(in6_dev);
2915 }
2916 
2917 static int addrconf_set_sit_dstaddr(struct net *net, struct net_device *dev,
2918 		struct in6_ifreq *ireq)
2919 {
2920 	struct ip_tunnel_parm p = { };
2921 	int err;
2922 
2923 	if (!(ipv6_addr_type(&ireq->ifr6_addr) & IPV6_ADDR_COMPATv4))
2924 		return -EADDRNOTAVAIL;
2925 
2926 	p.iph.daddr = ireq->ifr6_addr.s6_addr32[3];
2927 	p.iph.version = 4;
2928 	p.iph.ihl = 5;
2929 	p.iph.protocol = IPPROTO_IPV6;
2930 	p.iph.ttl = 64;
2931 
2932 	if (!dev->netdev_ops->ndo_tunnel_ctl)
2933 		return -EOPNOTSUPP;
2934 	err = dev->netdev_ops->ndo_tunnel_ctl(dev, &p, SIOCADDTUNNEL);
2935 	if (err)
2936 		return err;
2937 
2938 	dev = __dev_get_by_name(net, p.name);
2939 	if (!dev)
2940 		return -ENOBUFS;
2941 	return dev_open(dev, NULL);
2942 }
2943 
2944 /*
2945  *	Set destination address.
2946  *	Special case for SIT interfaces where we create a new "virtual"
2947  *	device.
2948  */
2949 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2950 {
2951 	struct net_device *dev;
2952 	struct in6_ifreq ireq;
2953 	int err = -ENODEV;
2954 
2955 	if (!IS_ENABLED(CONFIG_IPV6_SIT))
2956 		return -ENODEV;
2957 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2958 		return -EFAULT;
2959 
2960 	rtnl_lock();
2961 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2962 	if (dev && dev->type == ARPHRD_SIT)
2963 		err = addrconf_set_sit_dstaddr(net, dev, &ireq);
2964 	rtnl_unlock();
2965 	return err;
2966 }
2967 
2968 static int ipv6_mc_config(struct sock *sk, bool join,
2969 			  const struct in6_addr *addr, int ifindex)
2970 {
2971 	int ret;
2972 
2973 	ASSERT_RTNL();
2974 
2975 	lock_sock(sk);
2976 	if (join)
2977 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2978 	else
2979 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2980 	release_sock(sk);
2981 
2982 	return ret;
2983 }
2984 
2985 /*
2986  *	Manual configuration of address on an interface
2987  */
2988 static int inet6_addr_add(struct net *net, int ifindex,
2989 			  struct ifa6_config *cfg,
2990 			  struct netlink_ext_ack *extack)
2991 {
2992 	struct inet6_ifaddr *ifp;
2993 	struct inet6_dev *idev;
2994 	struct net_device *dev;
2995 	unsigned long timeout;
2996 	clock_t expires;
2997 	u32 flags;
2998 
2999 	ASSERT_RTNL();
3000 
3001 	if (cfg->plen > 128) {
3002 		NL_SET_ERR_MSG_MOD(extack, "Invalid prefix length");
3003 		return -EINVAL;
3004 	}
3005 
3006 	/* check the lifetime */
3007 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft) {
3008 		NL_SET_ERR_MSG_MOD(extack, "address lifetime invalid");
3009 		return -EINVAL;
3010 	}
3011 
3012 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR && cfg->plen != 64) {
3013 		NL_SET_ERR_MSG_MOD(extack, "address with \"mngtmpaddr\" flag must have a prefix length of 64");
3014 		return -EINVAL;
3015 	}
3016 
3017 	dev = __dev_get_by_index(net, ifindex);
3018 	if (!dev)
3019 		return -ENODEV;
3020 
3021 	idev = addrconf_add_dev(dev);
3022 	if (IS_ERR(idev)) {
3023 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
3024 		return PTR_ERR(idev);
3025 	}
3026 
3027 	if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
3028 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3029 					 true, cfg->pfx, ifindex);
3030 
3031 		if (ret < 0) {
3032 			NL_SET_ERR_MSG_MOD(extack, "Multicast auto join failed");
3033 			return ret;
3034 		}
3035 	}
3036 
3037 	cfg->scope = ipv6_addr_scope(cfg->pfx);
3038 
3039 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
3040 	if (addrconf_finite_timeout(timeout)) {
3041 		expires = jiffies_to_clock_t(timeout * HZ);
3042 		cfg->valid_lft = timeout;
3043 		flags = RTF_EXPIRES;
3044 	} else {
3045 		expires = 0;
3046 		flags = 0;
3047 		cfg->ifa_flags |= IFA_F_PERMANENT;
3048 	}
3049 
3050 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
3051 	if (addrconf_finite_timeout(timeout)) {
3052 		if (timeout == 0)
3053 			cfg->ifa_flags |= IFA_F_DEPRECATED;
3054 		cfg->preferred_lft = timeout;
3055 	}
3056 
3057 	ifp = ipv6_add_addr(idev, cfg, true, extack);
3058 	if (!IS_ERR(ifp)) {
3059 		if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
3060 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3061 					      ifp->rt_priority, dev, expires,
3062 					      flags, GFP_KERNEL);
3063 		}
3064 
3065 		/* Send a netlink notification if DAD is enabled and
3066 		 * optimistic flag is not set
3067 		 */
3068 		if (!(ifp->flags & (IFA_F_OPTIMISTIC | IFA_F_NODAD)))
3069 			ipv6_ifa_notify(0, ifp);
3070 		/*
3071 		 * Note that section 3.1 of RFC 4429 indicates
3072 		 * that the Optimistic flag should not be set for
3073 		 * manually configured addresses
3074 		 */
3075 		addrconf_dad_start(ifp);
3076 		if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR)
3077 			manage_tempaddrs(idev, ifp, cfg->valid_lft,
3078 					 cfg->preferred_lft, true, jiffies);
3079 		in6_ifa_put(ifp);
3080 		addrconf_verify_rtnl(net);
3081 		return 0;
3082 	} else if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
3083 		ipv6_mc_config(net->ipv6.mc_autojoin_sk, false,
3084 			       cfg->pfx, ifindex);
3085 	}
3086 
3087 	return PTR_ERR(ifp);
3088 }
3089 
3090 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
3091 			  const struct in6_addr *pfx, unsigned int plen,
3092 			  struct netlink_ext_ack *extack)
3093 {
3094 	struct inet6_ifaddr *ifp;
3095 	struct inet6_dev *idev;
3096 	struct net_device *dev;
3097 
3098 	if (plen > 128) {
3099 		NL_SET_ERR_MSG_MOD(extack, "Invalid prefix length");
3100 		return -EINVAL;
3101 	}
3102 
3103 	dev = __dev_get_by_index(net, ifindex);
3104 	if (!dev) {
3105 		NL_SET_ERR_MSG_MOD(extack, "Unable to find the interface");
3106 		return -ENODEV;
3107 	}
3108 
3109 	idev = __in6_dev_get(dev);
3110 	if (!idev) {
3111 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
3112 		return -ENXIO;
3113 	}
3114 
3115 	read_lock_bh(&idev->lock);
3116 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3117 		if (ifp->prefix_len == plen &&
3118 		    ipv6_addr_equal(pfx, &ifp->addr)) {
3119 			in6_ifa_hold(ifp);
3120 			read_unlock_bh(&idev->lock);
3121 
3122 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
3123 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
3124 				manage_tempaddrs(idev, ifp, 0, 0, false,
3125 						 jiffies);
3126 			ipv6_del_addr(ifp);
3127 			addrconf_verify_rtnl(net);
3128 			if (ipv6_addr_is_multicast(pfx)) {
3129 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3130 					       false, pfx, dev->ifindex);
3131 			}
3132 			return 0;
3133 		}
3134 	}
3135 	read_unlock_bh(&idev->lock);
3136 
3137 	NL_SET_ERR_MSG_MOD(extack, "address not found");
3138 	return -EADDRNOTAVAIL;
3139 }
3140 
3141 
3142 int addrconf_add_ifaddr(struct net *net, void __user *arg)
3143 {
3144 	struct ifa6_config cfg = {
3145 		.ifa_flags = IFA_F_PERMANENT,
3146 		.preferred_lft = INFINITY_LIFE_TIME,
3147 		.valid_lft = INFINITY_LIFE_TIME,
3148 	};
3149 	struct in6_ifreq ireq;
3150 	int err;
3151 
3152 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3153 		return -EPERM;
3154 
3155 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3156 		return -EFAULT;
3157 
3158 	cfg.pfx = &ireq.ifr6_addr;
3159 	cfg.plen = ireq.ifr6_prefixlen;
3160 
3161 	rtnl_lock();
3162 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &cfg, NULL);
3163 	rtnl_unlock();
3164 	return err;
3165 }
3166 
3167 int addrconf_del_ifaddr(struct net *net, void __user *arg)
3168 {
3169 	struct in6_ifreq ireq;
3170 	int err;
3171 
3172 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3173 		return -EPERM;
3174 
3175 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3176 		return -EFAULT;
3177 
3178 	rtnl_lock();
3179 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
3180 			     ireq.ifr6_prefixlen, NULL);
3181 	rtnl_unlock();
3182 	return err;
3183 }
3184 
3185 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
3186 		     int plen, int scope, u8 proto)
3187 {
3188 	struct inet6_ifaddr *ifp;
3189 	struct ifa6_config cfg = {
3190 		.pfx = addr,
3191 		.plen = plen,
3192 		.ifa_flags = IFA_F_PERMANENT,
3193 		.valid_lft = INFINITY_LIFE_TIME,
3194 		.preferred_lft = INFINITY_LIFE_TIME,
3195 		.scope = scope,
3196 		.ifa_proto = proto
3197 	};
3198 
3199 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3200 	if (!IS_ERR(ifp)) {
3201 		spin_lock_bh(&ifp->lock);
3202 		ifp->flags &= ~IFA_F_TENTATIVE;
3203 		spin_unlock_bh(&ifp->lock);
3204 		rt_genid_bump_ipv6(dev_net(idev->dev));
3205 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3206 		in6_ifa_put(ifp);
3207 	}
3208 }
3209 
3210 #if IS_ENABLED(CONFIG_IPV6_SIT) || IS_ENABLED(CONFIG_NET_IPGRE) || IS_ENABLED(CONFIG_IPV6_GRE)
3211 static void add_v4_addrs(struct inet6_dev *idev)
3212 {
3213 	struct in6_addr addr;
3214 	struct net_device *dev;
3215 	struct net *net = dev_net(idev->dev);
3216 	int scope, plen, offset = 0;
3217 	u32 pflags = 0;
3218 
3219 	ASSERT_RTNL();
3220 
3221 	memset(&addr, 0, sizeof(struct in6_addr));
3222 	/* in case of IP6GRE the dev_addr is an IPv6 and therefore we use only the last 4 bytes */
3223 	if (idev->dev->addr_len == sizeof(struct in6_addr))
3224 		offset = sizeof(struct in6_addr) - 4;
3225 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr + offset, 4);
3226 
3227 	if (!(idev->dev->flags & IFF_POINTOPOINT) && idev->dev->type == ARPHRD_SIT) {
3228 		scope = IPV6_ADDR_COMPATv4;
3229 		plen = 96;
3230 		pflags |= RTF_NONEXTHOP;
3231 	} else {
3232 		if (idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_NONE)
3233 			return;
3234 
3235 		addr.s6_addr32[0] = htonl(0xfe800000);
3236 		scope = IFA_LINK;
3237 		plen = 64;
3238 	}
3239 
3240 	if (addr.s6_addr32[3]) {
3241 		add_addr(idev, &addr, plen, scope, IFAPROT_UNSPEC);
3242 		addrconf_prefix_route(&addr, plen, 0, idev->dev, 0, pflags,
3243 				      GFP_KERNEL);
3244 		return;
3245 	}
3246 
3247 	for_each_netdev(net, dev) {
3248 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3249 		if (in_dev && (dev->flags & IFF_UP)) {
3250 			struct in_ifaddr *ifa;
3251 			int flag = scope;
3252 
3253 			in_dev_for_each_ifa_rtnl(ifa, in_dev) {
3254 				addr.s6_addr32[3] = ifa->ifa_local;
3255 
3256 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3257 					continue;
3258 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3259 					if (idev->dev->flags&IFF_POINTOPOINT)
3260 						continue;
3261 					flag |= IFA_HOST;
3262 				}
3263 
3264 				add_addr(idev, &addr, plen, flag,
3265 					 IFAPROT_UNSPEC);
3266 				addrconf_prefix_route(&addr, plen, 0, idev->dev,
3267 						      0, pflags, GFP_KERNEL);
3268 			}
3269 		}
3270 	}
3271 }
3272 #endif
3273 
3274 static void init_loopback(struct net_device *dev)
3275 {
3276 	struct inet6_dev  *idev;
3277 
3278 	/* ::1 */
3279 
3280 	ASSERT_RTNL();
3281 
3282 	idev = ipv6_find_idev(dev);
3283 	if (IS_ERR(idev)) {
3284 		pr_debug("%s: add_dev failed\n", __func__);
3285 		return;
3286 	}
3287 
3288 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST, IFAPROT_KERNEL_LO);
3289 }
3290 
3291 void addrconf_add_linklocal(struct inet6_dev *idev,
3292 			    const struct in6_addr *addr, u32 flags)
3293 {
3294 	struct ifa6_config cfg = {
3295 		.pfx = addr,
3296 		.plen = 64,
3297 		.ifa_flags = flags | IFA_F_PERMANENT,
3298 		.valid_lft = INFINITY_LIFE_TIME,
3299 		.preferred_lft = INFINITY_LIFE_TIME,
3300 		.scope = IFA_LINK,
3301 		.ifa_proto = IFAPROT_KERNEL_LL
3302 	};
3303 	struct inet6_ifaddr *ifp;
3304 
3305 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3306 	if ((READ_ONCE(dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad) ||
3307 	     READ_ONCE(idev->cnf.optimistic_dad)) &&
3308 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3309 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
3310 #endif
3311 
3312 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3313 	if (!IS_ERR(ifp)) {
3314 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, 0, idev->dev,
3315 				      0, 0, GFP_ATOMIC);
3316 		addrconf_dad_start(ifp);
3317 		in6_ifa_put(ifp);
3318 	}
3319 }
3320 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3321 
3322 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3323 {
3324 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3325 		return true;
3326 
3327 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3328 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3329 		return true;
3330 
3331 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3332 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3333 		return true;
3334 
3335 	return false;
3336 }
3337 
3338 static int ipv6_generate_stable_address(struct in6_addr *address,
3339 					u8 dad_count,
3340 					const struct inet6_dev *idev)
3341 {
3342 	static DEFINE_SPINLOCK(lock);
3343 	static __u32 digest[SHA1_DIGEST_WORDS];
3344 	static __u32 workspace[SHA1_WORKSPACE_WORDS];
3345 
3346 	static union {
3347 		char __data[SHA1_BLOCK_SIZE];
3348 		struct {
3349 			struct in6_addr secret;
3350 			__be32 prefix[2];
3351 			unsigned char hwaddr[MAX_ADDR_LEN];
3352 			u8 dad_count;
3353 		} __packed;
3354 	} data;
3355 
3356 	struct in6_addr secret;
3357 	struct in6_addr temp;
3358 	struct net *net = dev_net(idev->dev);
3359 
3360 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3361 
3362 	if (idev->cnf.stable_secret.initialized)
3363 		secret = idev->cnf.stable_secret.secret;
3364 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3365 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3366 	else
3367 		return -1;
3368 
3369 retry:
3370 	spin_lock_bh(&lock);
3371 
3372 	sha1_init(digest);
3373 	memset(&data, 0, sizeof(data));
3374 	memset(workspace, 0, sizeof(workspace));
3375 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3376 	data.prefix[0] = address->s6_addr32[0];
3377 	data.prefix[1] = address->s6_addr32[1];
3378 	data.secret = secret;
3379 	data.dad_count = dad_count;
3380 
3381 	sha1_transform(digest, data.__data, workspace);
3382 
3383 	temp = *address;
3384 	temp.s6_addr32[2] = (__force __be32)digest[0];
3385 	temp.s6_addr32[3] = (__force __be32)digest[1];
3386 
3387 	spin_unlock_bh(&lock);
3388 
3389 	if (ipv6_reserved_interfaceid(temp)) {
3390 		dad_count++;
3391 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3392 			return -1;
3393 		goto retry;
3394 	}
3395 
3396 	*address = temp;
3397 	return 0;
3398 }
3399 
3400 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3401 {
3402 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3403 
3404 	if (s->initialized)
3405 		return;
3406 	s = &idev->cnf.stable_secret;
3407 	get_random_bytes(&s->secret, sizeof(s->secret));
3408 	s->initialized = true;
3409 }
3410 
3411 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3412 {
3413 	struct in6_addr addr;
3414 
3415 	/* no link local addresses on L3 master devices */
3416 	if (netif_is_l3_master(idev->dev))
3417 		return;
3418 
3419 	/* no link local addresses on devices flagged as slaves */
3420 	if (idev->dev->priv_flags & IFF_NO_ADDRCONF)
3421 		return;
3422 
3423 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3424 
3425 	switch (idev->cnf.addr_gen_mode) {
3426 	case IN6_ADDR_GEN_MODE_RANDOM:
3427 		ipv6_gen_mode_random_init(idev);
3428 		fallthrough;
3429 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3430 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3431 			addrconf_add_linklocal(idev, &addr,
3432 					       IFA_F_STABLE_PRIVACY);
3433 		else if (prefix_route)
3434 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3435 					      0, 0, GFP_KERNEL);
3436 		break;
3437 	case IN6_ADDR_GEN_MODE_EUI64:
3438 		/* addrconf_add_linklocal also adds a prefix_route and we
3439 		 * only need to care about prefix routes if ipv6_generate_eui64
3440 		 * couldn't generate one.
3441 		 */
3442 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3443 			addrconf_add_linklocal(idev, &addr, 0);
3444 		else if (prefix_route)
3445 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3446 					      0, 0, GFP_KERNEL);
3447 		break;
3448 	case IN6_ADDR_GEN_MODE_NONE:
3449 	default:
3450 		/* will not add any link local address */
3451 		break;
3452 	}
3453 }
3454 
3455 static void addrconf_dev_config(struct net_device *dev)
3456 {
3457 	struct inet6_dev *idev;
3458 
3459 	ASSERT_RTNL();
3460 
3461 	if ((dev->type != ARPHRD_ETHER) &&
3462 	    (dev->type != ARPHRD_FDDI) &&
3463 	    (dev->type != ARPHRD_ARCNET) &&
3464 	    (dev->type != ARPHRD_INFINIBAND) &&
3465 	    (dev->type != ARPHRD_IEEE1394) &&
3466 	    (dev->type != ARPHRD_TUNNEL6) &&
3467 	    (dev->type != ARPHRD_6LOWPAN) &&
3468 	    (dev->type != ARPHRD_TUNNEL) &&
3469 	    (dev->type != ARPHRD_NONE) &&
3470 	    (dev->type != ARPHRD_RAWIP)) {
3471 		/* Alas, we support only Ethernet autoconfiguration. */
3472 		idev = __in6_dev_get(dev);
3473 		if (!IS_ERR_OR_NULL(idev) && dev->flags & IFF_UP &&
3474 		    dev->flags & IFF_MULTICAST)
3475 			ipv6_mc_up(idev);
3476 		return;
3477 	}
3478 
3479 	idev = addrconf_add_dev(dev);
3480 	if (IS_ERR(idev))
3481 		return;
3482 
3483 	/* this device type has no EUI support */
3484 	if (dev->type == ARPHRD_NONE &&
3485 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3486 		WRITE_ONCE(idev->cnf.addr_gen_mode,
3487 			   IN6_ADDR_GEN_MODE_RANDOM);
3488 
3489 	addrconf_addr_gen(idev, false);
3490 }
3491 
3492 #if IS_ENABLED(CONFIG_IPV6_SIT)
3493 static void addrconf_sit_config(struct net_device *dev)
3494 {
3495 	struct inet6_dev *idev;
3496 
3497 	ASSERT_RTNL();
3498 
3499 	/*
3500 	 * Configure the tunnel with one of our IPv4
3501 	 * addresses... we should configure all of
3502 	 * our v4 addrs in the tunnel
3503 	 */
3504 
3505 	idev = ipv6_find_idev(dev);
3506 	if (IS_ERR(idev)) {
3507 		pr_debug("%s: add_dev failed\n", __func__);
3508 		return;
3509 	}
3510 
3511 	if (dev->priv_flags & IFF_ISATAP) {
3512 		addrconf_addr_gen(idev, false);
3513 		return;
3514 	}
3515 
3516 	add_v4_addrs(idev);
3517 
3518 	if (dev->flags&IFF_POINTOPOINT)
3519 		addrconf_add_mroute(dev);
3520 }
3521 #endif
3522 
3523 #if IS_ENABLED(CONFIG_NET_IPGRE) || IS_ENABLED(CONFIG_IPV6_GRE)
3524 static void addrconf_gre_config(struct net_device *dev)
3525 {
3526 	struct inet6_dev *idev;
3527 
3528 	ASSERT_RTNL();
3529 
3530 	idev = ipv6_find_idev(dev);
3531 	if (IS_ERR(idev)) {
3532 		pr_debug("%s: add_dev failed\n", __func__);
3533 		return;
3534 	}
3535 
3536 	if (dev->type == ARPHRD_ETHER) {
3537 		addrconf_addr_gen(idev, true);
3538 		return;
3539 	}
3540 
3541 	add_v4_addrs(idev);
3542 
3543 	if (dev->flags & IFF_POINTOPOINT)
3544 		addrconf_add_mroute(dev);
3545 }
3546 #endif
3547 
3548 static void addrconf_init_auto_addrs(struct net_device *dev)
3549 {
3550 	switch (dev->type) {
3551 #if IS_ENABLED(CONFIG_IPV6_SIT)
3552 	case ARPHRD_SIT:
3553 		addrconf_sit_config(dev);
3554 		break;
3555 #endif
3556 #if IS_ENABLED(CONFIG_NET_IPGRE) || IS_ENABLED(CONFIG_IPV6_GRE)
3557 	case ARPHRD_IP6GRE:
3558 	case ARPHRD_IPGRE:
3559 		addrconf_gre_config(dev);
3560 		break;
3561 #endif
3562 	case ARPHRD_LOOPBACK:
3563 		init_loopback(dev);
3564 		break;
3565 
3566 	default:
3567 		addrconf_dev_config(dev);
3568 		break;
3569 	}
3570 }
3571 
3572 static int fixup_permanent_addr(struct net *net,
3573 				struct inet6_dev *idev,
3574 				struct inet6_ifaddr *ifp)
3575 {
3576 	/* !fib6_node means the host route was removed from the
3577 	 * FIB, for example, if 'lo' device is taken down. In that
3578 	 * case regenerate the host route.
3579 	 */
3580 	if (!ifp->rt || !ifp->rt->fib6_node) {
3581 		struct fib6_info *f6i, *prev;
3582 
3583 		f6i = addrconf_f6i_alloc(net, idev, &ifp->addr, false,
3584 					 GFP_ATOMIC, NULL);
3585 		if (IS_ERR(f6i))
3586 			return PTR_ERR(f6i);
3587 
3588 		/* ifp->rt can be accessed outside of rtnl */
3589 		spin_lock(&ifp->lock);
3590 		prev = ifp->rt;
3591 		ifp->rt = f6i;
3592 		spin_unlock(&ifp->lock);
3593 
3594 		fib6_info_release(prev);
3595 	}
3596 
3597 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3598 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3599 				      ifp->rt_priority, idev->dev, 0, 0,
3600 				      GFP_ATOMIC);
3601 	}
3602 
3603 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3604 		addrconf_dad_start(ifp);
3605 
3606 	return 0;
3607 }
3608 
3609 static void addrconf_permanent_addr(struct net *net, struct net_device *dev)
3610 {
3611 	struct inet6_ifaddr *ifp, *tmp;
3612 	struct inet6_dev *idev;
3613 
3614 	idev = __in6_dev_get(dev);
3615 	if (!idev)
3616 		return;
3617 
3618 	write_lock_bh(&idev->lock);
3619 
3620 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3621 		if ((ifp->flags & IFA_F_PERMANENT) &&
3622 		    fixup_permanent_addr(net, idev, ifp) < 0) {
3623 			write_unlock_bh(&idev->lock);
3624 			in6_ifa_hold(ifp);
3625 			ipv6_del_addr(ifp);
3626 			write_lock_bh(&idev->lock);
3627 
3628 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3629 					     idev->dev->name, &ifp->addr);
3630 		}
3631 	}
3632 
3633 	write_unlock_bh(&idev->lock);
3634 }
3635 
3636 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3637 			   void *ptr)
3638 {
3639 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3640 	struct netdev_notifier_change_info *change_info;
3641 	struct netdev_notifier_changeupper_info *info;
3642 	struct inet6_dev *idev = __in6_dev_get(dev);
3643 	struct net *net = dev_net(dev);
3644 	int run_pending = 0;
3645 	int err;
3646 
3647 	switch (event) {
3648 	case NETDEV_REGISTER:
3649 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3650 			idev = ipv6_add_dev(dev);
3651 			if (IS_ERR(idev))
3652 				return notifier_from_errno(PTR_ERR(idev));
3653 		}
3654 		break;
3655 
3656 	case NETDEV_CHANGEMTU:
3657 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3658 		if (dev->mtu < IPV6_MIN_MTU) {
3659 			addrconf_ifdown(dev, dev != net->loopback_dev);
3660 			break;
3661 		}
3662 
3663 		if (idev) {
3664 			rt6_mtu_change(dev, dev->mtu);
3665 			WRITE_ONCE(idev->cnf.mtu6, dev->mtu);
3666 			break;
3667 		}
3668 
3669 		/* allocate new idev */
3670 		idev = ipv6_add_dev(dev);
3671 		if (IS_ERR(idev))
3672 			break;
3673 
3674 		/* device is still not ready */
3675 		if (!(idev->if_flags & IF_READY))
3676 			break;
3677 
3678 		run_pending = 1;
3679 		fallthrough;
3680 	case NETDEV_UP:
3681 	case NETDEV_CHANGE:
3682 		if (idev && idev->cnf.disable_ipv6)
3683 			break;
3684 
3685 		if (dev->priv_flags & IFF_NO_ADDRCONF) {
3686 			if (event == NETDEV_UP && !IS_ERR_OR_NULL(idev) &&
3687 			    dev->flags & IFF_UP && dev->flags & IFF_MULTICAST)
3688 				ipv6_mc_up(idev);
3689 			break;
3690 		}
3691 
3692 		if (event == NETDEV_UP) {
3693 			/* restore routes for permanent addresses */
3694 			addrconf_permanent_addr(net, dev);
3695 
3696 			if (!addrconf_link_ready(dev)) {
3697 				/* device is not ready yet. */
3698 				pr_debug("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3699 					 dev->name);
3700 				break;
3701 			}
3702 
3703 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3704 				idev = ipv6_add_dev(dev);
3705 
3706 			if (!IS_ERR_OR_NULL(idev)) {
3707 				idev->if_flags |= IF_READY;
3708 				run_pending = 1;
3709 			}
3710 		} else if (event == NETDEV_CHANGE) {
3711 			if (!addrconf_link_ready(dev)) {
3712 				/* device is still not ready. */
3713 				rt6_sync_down_dev(dev, event);
3714 				break;
3715 			}
3716 
3717 			if (!IS_ERR_OR_NULL(idev)) {
3718 				if (idev->if_flags & IF_READY) {
3719 					/* device is already configured -
3720 					 * but resend MLD reports, we might
3721 					 * have roamed and need to update
3722 					 * multicast snooping switches
3723 					 */
3724 					ipv6_mc_up(idev);
3725 					change_info = ptr;
3726 					if (change_info->flags_changed & IFF_NOARP)
3727 						addrconf_dad_run(idev, true);
3728 					rt6_sync_up(dev, RTNH_F_LINKDOWN);
3729 					break;
3730 				}
3731 				idev->if_flags |= IF_READY;
3732 			}
3733 
3734 			pr_debug("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3735 				 dev->name);
3736 
3737 			run_pending = 1;
3738 		}
3739 
3740 		addrconf_init_auto_addrs(dev);
3741 
3742 		if (!IS_ERR_OR_NULL(idev)) {
3743 			if (run_pending)
3744 				addrconf_dad_run(idev, false);
3745 
3746 			/* Device has an address by now */
3747 			rt6_sync_up(dev, RTNH_F_DEAD);
3748 
3749 			/*
3750 			 * If the MTU changed during the interface down,
3751 			 * when the interface up, the changed MTU must be
3752 			 * reflected in the idev as well as routers.
3753 			 */
3754 			if (idev->cnf.mtu6 != dev->mtu &&
3755 			    dev->mtu >= IPV6_MIN_MTU) {
3756 				rt6_mtu_change(dev, dev->mtu);
3757 				WRITE_ONCE(idev->cnf.mtu6, dev->mtu);
3758 			}
3759 			WRITE_ONCE(idev->tstamp, jiffies);
3760 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3761 
3762 			/*
3763 			 * If the changed mtu during down is lower than
3764 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3765 			 */
3766 			if (dev->mtu < IPV6_MIN_MTU)
3767 				addrconf_ifdown(dev, dev != net->loopback_dev);
3768 		}
3769 		break;
3770 
3771 	case NETDEV_DOWN:
3772 	case NETDEV_UNREGISTER:
3773 		/*
3774 		 *	Remove all addresses from this interface.
3775 		 */
3776 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3777 		break;
3778 
3779 	case NETDEV_CHANGENAME:
3780 		if (idev) {
3781 			snmp6_unregister_dev(idev);
3782 			addrconf_sysctl_unregister(idev);
3783 			err = addrconf_sysctl_register(idev);
3784 			if (err)
3785 				return notifier_from_errno(err);
3786 			err = snmp6_register_dev(idev);
3787 			if (err) {
3788 				addrconf_sysctl_unregister(idev);
3789 				return notifier_from_errno(err);
3790 			}
3791 		}
3792 		break;
3793 
3794 	case NETDEV_PRE_TYPE_CHANGE:
3795 	case NETDEV_POST_TYPE_CHANGE:
3796 		if (idev)
3797 			addrconf_type_change(dev, event);
3798 		break;
3799 
3800 	case NETDEV_CHANGEUPPER:
3801 		info = ptr;
3802 
3803 		/* flush all routes if dev is linked to or unlinked from
3804 		 * an L3 master device (e.g., VRF)
3805 		 */
3806 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3807 			addrconf_ifdown(dev, false);
3808 	}
3809 
3810 	return NOTIFY_OK;
3811 }
3812 
3813 /*
3814  *	addrconf module should be notified of a device going up
3815  */
3816 static struct notifier_block ipv6_dev_notf = {
3817 	.notifier_call = addrconf_notify,
3818 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3819 };
3820 
3821 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3822 {
3823 	struct inet6_dev *idev;
3824 	ASSERT_RTNL();
3825 
3826 	idev = __in6_dev_get(dev);
3827 
3828 	if (event == NETDEV_POST_TYPE_CHANGE)
3829 		ipv6_mc_remap(idev);
3830 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3831 		ipv6_mc_unmap(idev);
3832 }
3833 
3834 static bool addr_is_local(const struct in6_addr *addr)
3835 {
3836 	return ipv6_addr_type(addr) &
3837 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3838 }
3839 
3840 static int addrconf_ifdown(struct net_device *dev, bool unregister)
3841 {
3842 	unsigned long event = unregister ? NETDEV_UNREGISTER : NETDEV_DOWN;
3843 	struct net *net = dev_net(dev);
3844 	struct inet6_dev *idev;
3845 	struct inet6_ifaddr *ifa;
3846 	LIST_HEAD(tmp_addr_list);
3847 	bool keep_addr = false;
3848 	bool was_ready;
3849 	int state, i;
3850 
3851 	ASSERT_RTNL();
3852 
3853 	rt6_disable_ip(dev, event);
3854 
3855 	idev = __in6_dev_get(dev);
3856 	if (!idev)
3857 		return -ENODEV;
3858 
3859 	/*
3860 	 * Step 1: remove reference to ipv6 device from parent device.
3861 	 *	   Do not dev_put!
3862 	 */
3863 	if (unregister) {
3864 		idev->dead = 1;
3865 
3866 		/* protected by rtnl_lock */
3867 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3868 
3869 		/* Step 1.5: remove snmp6 entry */
3870 		snmp6_unregister_dev(idev);
3871 
3872 	}
3873 
3874 	/* combine the user config with event to determine if permanent
3875 	 * addresses are to be removed from address hash table
3876 	 */
3877 	if (!unregister && !idev->cnf.disable_ipv6) {
3878 		/* aggregate the system setting and interface setting */
3879 		int _keep_addr = READ_ONCE(net->ipv6.devconf_all->keep_addr_on_down);
3880 
3881 		if (!_keep_addr)
3882 			_keep_addr = READ_ONCE(idev->cnf.keep_addr_on_down);
3883 
3884 		keep_addr = (_keep_addr > 0);
3885 	}
3886 
3887 	/* Step 2: clear hash table */
3888 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3889 		struct hlist_head *h = &net->ipv6.inet6_addr_lst[i];
3890 
3891 		spin_lock_bh(&net->ipv6.addrconf_hash_lock);
3892 restart:
3893 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3894 			if (ifa->idev == idev) {
3895 				addrconf_del_dad_work(ifa);
3896 				/* combined flag + permanent flag decide if
3897 				 * address is retained on a down event
3898 				 */
3899 				if (!keep_addr ||
3900 				    !(ifa->flags & IFA_F_PERMANENT) ||
3901 				    addr_is_local(&ifa->addr)) {
3902 					hlist_del_init_rcu(&ifa->addr_lst);
3903 					goto restart;
3904 				}
3905 			}
3906 		}
3907 		spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
3908 	}
3909 
3910 	write_lock_bh(&idev->lock);
3911 
3912 	addrconf_del_rs_timer(idev);
3913 
3914 	/* Step 2: clear flags for stateless addrconf, repeated down
3915 	 *         detection
3916 	 */
3917 	was_ready = idev->if_flags & IF_READY;
3918 	if (!unregister)
3919 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3920 
3921 	/* Step 3: clear tempaddr list */
3922 	while (!list_empty(&idev->tempaddr_list)) {
3923 		ifa = list_first_entry(&idev->tempaddr_list,
3924 				       struct inet6_ifaddr, tmp_list);
3925 		list_del(&ifa->tmp_list);
3926 		write_unlock_bh(&idev->lock);
3927 		spin_lock_bh(&ifa->lock);
3928 
3929 		if (ifa->ifpub) {
3930 			in6_ifa_put(ifa->ifpub);
3931 			ifa->ifpub = NULL;
3932 		}
3933 		spin_unlock_bh(&ifa->lock);
3934 		in6_ifa_put(ifa);
3935 		write_lock_bh(&idev->lock);
3936 	}
3937 
3938 	list_for_each_entry(ifa, &idev->addr_list, if_list)
3939 		list_add_tail(&ifa->if_list_aux, &tmp_addr_list);
3940 	write_unlock_bh(&idev->lock);
3941 
3942 	while (!list_empty(&tmp_addr_list)) {
3943 		struct fib6_info *rt = NULL;
3944 		bool keep;
3945 
3946 		ifa = list_first_entry(&tmp_addr_list,
3947 				       struct inet6_ifaddr, if_list_aux);
3948 		list_del(&ifa->if_list_aux);
3949 
3950 		addrconf_del_dad_work(ifa);
3951 
3952 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3953 			!addr_is_local(&ifa->addr);
3954 
3955 		spin_lock_bh(&ifa->lock);
3956 
3957 		if (keep) {
3958 			/* set state to skip the notifier below */
3959 			state = INET6_IFADDR_STATE_DEAD;
3960 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3961 			if (!(ifa->flags & IFA_F_NODAD))
3962 				ifa->flags |= IFA_F_TENTATIVE;
3963 
3964 			rt = ifa->rt;
3965 			ifa->rt = NULL;
3966 		} else {
3967 			state = ifa->state;
3968 			ifa->state = INET6_IFADDR_STATE_DEAD;
3969 		}
3970 
3971 		spin_unlock_bh(&ifa->lock);
3972 
3973 		if (rt)
3974 			ip6_del_rt(net, rt, false);
3975 
3976 		if (state != INET6_IFADDR_STATE_DEAD) {
3977 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3978 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3979 		} else {
3980 			if (idev->cnf.forwarding)
3981 				addrconf_leave_anycast(ifa);
3982 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3983 		}
3984 
3985 		if (!keep) {
3986 			write_lock_bh(&idev->lock);
3987 			list_del_rcu(&ifa->if_list);
3988 			write_unlock_bh(&idev->lock);
3989 			in6_ifa_put(ifa);
3990 		}
3991 	}
3992 
3993 	/* Step 5: Discard anycast and multicast list */
3994 	if (unregister) {
3995 		ipv6_ac_destroy_dev(idev);
3996 		ipv6_mc_destroy_dev(idev);
3997 	} else if (was_ready) {
3998 		ipv6_mc_down(idev);
3999 	}
4000 
4001 	WRITE_ONCE(idev->tstamp, jiffies);
4002 	idev->ra_mtu = 0;
4003 
4004 	/* Last: Shot the device (if unregistered) */
4005 	if (unregister) {
4006 		addrconf_sysctl_unregister(idev);
4007 		neigh_parms_release(&nd_tbl, idev->nd_parms);
4008 		neigh_ifdown(&nd_tbl, dev);
4009 		in6_dev_put(idev);
4010 	}
4011 	return 0;
4012 }
4013 
4014 static void addrconf_rs_timer(struct timer_list *t)
4015 {
4016 	struct inet6_dev *idev = from_timer(idev, t, rs_timer);
4017 	struct net_device *dev = idev->dev;
4018 	struct in6_addr lladdr;
4019 	int rtr_solicits;
4020 
4021 	write_lock(&idev->lock);
4022 	if (idev->dead || !(idev->if_flags & IF_READY))
4023 		goto out;
4024 
4025 	if (!ipv6_accept_ra(idev))
4026 		goto out;
4027 
4028 	/* Announcement received after solicitation was sent */
4029 	if (idev->if_flags & IF_RA_RCVD)
4030 		goto out;
4031 
4032 	rtr_solicits = READ_ONCE(idev->cnf.rtr_solicits);
4033 
4034 	if (idev->rs_probes++ < rtr_solicits || rtr_solicits < 0) {
4035 		write_unlock(&idev->lock);
4036 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4037 			ndisc_send_rs(dev, &lladdr,
4038 				      &in6addr_linklocal_allrouters);
4039 		else
4040 			goto put;
4041 
4042 		write_lock(&idev->lock);
4043 		idev->rs_interval = rfc3315_s14_backoff_update(
4044 				idev->rs_interval,
4045 				READ_ONCE(idev->cnf.rtr_solicit_max_interval));
4046 		/* The wait after the last probe can be shorter */
4047 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
4048 					     READ_ONCE(idev->cnf.rtr_solicits)) ?
4049 				      READ_ONCE(idev->cnf.rtr_solicit_delay) :
4050 				      idev->rs_interval);
4051 	} else {
4052 		/*
4053 		 * Note: we do not support deprecated "all on-link"
4054 		 * assumption any longer.
4055 		 */
4056 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
4057 	}
4058 
4059 out:
4060 	write_unlock(&idev->lock);
4061 put:
4062 	in6_dev_put(idev);
4063 }
4064 
4065 /*
4066  *	Duplicate Address Detection
4067  */
4068 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
4069 {
4070 	struct inet6_dev *idev = ifp->idev;
4071 	unsigned long rand_num;
4072 	u64 nonce;
4073 
4074 	if (ifp->flags & IFA_F_OPTIMISTIC)
4075 		rand_num = 0;
4076 	else
4077 		rand_num = get_random_u32_below(
4078 				READ_ONCE(idev->cnf.rtr_solicit_delay) ? : 1);
4079 
4080 	nonce = 0;
4081 	if (READ_ONCE(idev->cnf.enhanced_dad) ||
4082 	    READ_ONCE(dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad)) {
4083 		do
4084 			get_random_bytes(&nonce, 6);
4085 		while (nonce == 0);
4086 	}
4087 	ifp->dad_nonce = nonce;
4088 	ifp->dad_probes = READ_ONCE(idev->cnf.dad_transmits);
4089 	addrconf_mod_dad_work(ifp, rand_num);
4090 }
4091 
4092 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
4093 {
4094 	struct inet6_dev *idev = ifp->idev;
4095 	struct net_device *dev = idev->dev;
4096 	bool bump_id, notify = false;
4097 	struct net *net;
4098 
4099 	addrconf_join_solict(dev, &ifp->addr);
4100 
4101 	read_lock_bh(&idev->lock);
4102 	spin_lock(&ifp->lock);
4103 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
4104 		goto out;
4105 
4106 	net = dev_net(dev);
4107 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
4108 	    (READ_ONCE(net->ipv6.devconf_all->accept_dad) < 1 &&
4109 	     READ_ONCE(idev->cnf.accept_dad) < 1) ||
4110 	    !(ifp->flags&IFA_F_TENTATIVE) ||
4111 	    ifp->flags & IFA_F_NODAD) {
4112 		bool send_na = false;
4113 
4114 		if (ifp->flags & IFA_F_TENTATIVE &&
4115 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4116 			send_na = true;
4117 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4118 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4119 		spin_unlock(&ifp->lock);
4120 		read_unlock_bh(&idev->lock);
4121 
4122 		addrconf_dad_completed(ifp, bump_id, send_na);
4123 		return;
4124 	}
4125 
4126 	if (!(idev->if_flags & IF_READY)) {
4127 		spin_unlock(&ifp->lock);
4128 		read_unlock_bh(&idev->lock);
4129 		/*
4130 		 * If the device is not ready:
4131 		 * - keep it tentative if it is a permanent address.
4132 		 * - otherwise, kill it.
4133 		 */
4134 		in6_ifa_hold(ifp);
4135 		addrconf_dad_stop(ifp, 0);
4136 		return;
4137 	}
4138 
4139 	/*
4140 	 * Optimistic nodes can start receiving
4141 	 * Frames right away
4142 	 */
4143 	if (ifp->flags & IFA_F_OPTIMISTIC) {
4144 		ip6_ins_rt(net, ifp->rt);
4145 		if (ipv6_use_optimistic_addr(net, idev)) {
4146 			/* Because optimistic nodes can use this address,
4147 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
4148 			 */
4149 			notify = true;
4150 		}
4151 	}
4152 
4153 	addrconf_dad_kick(ifp);
4154 out:
4155 	spin_unlock(&ifp->lock);
4156 	read_unlock_bh(&idev->lock);
4157 	if (notify)
4158 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
4159 }
4160 
4161 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
4162 {
4163 	bool begin_dad = false;
4164 
4165 	spin_lock_bh(&ifp->lock);
4166 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
4167 		ifp->state = INET6_IFADDR_STATE_PREDAD;
4168 		begin_dad = true;
4169 	}
4170 	spin_unlock_bh(&ifp->lock);
4171 
4172 	if (begin_dad)
4173 		addrconf_mod_dad_work(ifp, 0);
4174 }
4175 
4176 static void addrconf_dad_work(struct work_struct *w)
4177 {
4178 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
4179 						struct inet6_ifaddr,
4180 						dad_work);
4181 	struct inet6_dev *idev = ifp->idev;
4182 	bool bump_id, disable_ipv6 = false;
4183 	struct in6_addr mcaddr;
4184 
4185 	enum {
4186 		DAD_PROCESS,
4187 		DAD_BEGIN,
4188 		DAD_ABORT,
4189 	} action = DAD_PROCESS;
4190 
4191 	rtnl_lock();
4192 
4193 	spin_lock_bh(&ifp->lock);
4194 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
4195 		action = DAD_BEGIN;
4196 		ifp->state = INET6_IFADDR_STATE_DAD;
4197 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
4198 		action = DAD_ABORT;
4199 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
4200 
4201 		if ((READ_ONCE(dev_net(idev->dev)->ipv6.devconf_all->accept_dad) > 1 ||
4202 		     READ_ONCE(idev->cnf.accept_dad) > 1) &&
4203 		    !idev->cnf.disable_ipv6 &&
4204 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
4205 			struct in6_addr addr;
4206 
4207 			addr.s6_addr32[0] = htonl(0xfe800000);
4208 			addr.s6_addr32[1] = 0;
4209 
4210 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
4211 			    ipv6_addr_equal(&ifp->addr, &addr)) {
4212 				/* DAD failed for link-local based on MAC */
4213 				WRITE_ONCE(idev->cnf.disable_ipv6, 1);
4214 
4215 				pr_info("%s: IPv6 being disabled!\n",
4216 					ifp->idev->dev->name);
4217 				disable_ipv6 = true;
4218 			}
4219 		}
4220 	}
4221 	spin_unlock_bh(&ifp->lock);
4222 
4223 	if (action == DAD_BEGIN) {
4224 		addrconf_dad_begin(ifp);
4225 		goto out;
4226 	} else if (action == DAD_ABORT) {
4227 		in6_ifa_hold(ifp);
4228 		addrconf_dad_stop(ifp, 1);
4229 		if (disable_ipv6)
4230 			addrconf_ifdown(idev->dev, false);
4231 		goto out;
4232 	}
4233 
4234 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
4235 		goto out;
4236 
4237 	write_lock_bh(&idev->lock);
4238 	if (idev->dead || !(idev->if_flags & IF_READY)) {
4239 		write_unlock_bh(&idev->lock);
4240 		goto out;
4241 	}
4242 
4243 	spin_lock(&ifp->lock);
4244 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
4245 		spin_unlock(&ifp->lock);
4246 		write_unlock_bh(&idev->lock);
4247 		goto out;
4248 	}
4249 
4250 	if (ifp->dad_probes == 0) {
4251 		bool send_na = false;
4252 
4253 		/*
4254 		 * DAD was successful
4255 		 */
4256 
4257 		if (ifp->flags & IFA_F_TENTATIVE &&
4258 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4259 			send_na = true;
4260 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4261 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4262 		spin_unlock(&ifp->lock);
4263 		write_unlock_bh(&idev->lock);
4264 
4265 		addrconf_dad_completed(ifp, bump_id, send_na);
4266 
4267 		goto out;
4268 	}
4269 
4270 	ifp->dad_probes--;
4271 	addrconf_mod_dad_work(ifp,
4272 			      max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME),
4273 				  HZ/100));
4274 	spin_unlock(&ifp->lock);
4275 	write_unlock_bh(&idev->lock);
4276 
4277 	/* send a neighbour solicitation for our addr */
4278 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4279 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4280 		      ifp->dad_nonce);
4281 out:
4282 	in6_ifa_put(ifp);
4283 	rtnl_unlock();
4284 }
4285 
4286 /* ifp->idev must be at least read locked */
4287 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4288 {
4289 	struct inet6_ifaddr *ifpiter;
4290 	struct inet6_dev *idev = ifp->idev;
4291 
4292 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4293 		if (ifpiter->scope > IFA_LINK)
4294 			break;
4295 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4296 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4297 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4298 		    IFA_F_PERMANENT)
4299 			return false;
4300 	}
4301 	return true;
4302 }
4303 
4304 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
4305 				   bool send_na)
4306 {
4307 	struct net_device *dev = ifp->idev->dev;
4308 	struct in6_addr lladdr;
4309 	bool send_rs, send_mld;
4310 
4311 	addrconf_del_dad_work(ifp);
4312 
4313 	/*
4314 	 *	Configure the address for reception. Now it is valid.
4315 	 */
4316 
4317 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4318 
4319 	/* If added prefix is link local and we are prepared to process
4320 	   router advertisements, start sending router solicitations.
4321 	 */
4322 
4323 	read_lock_bh(&ifp->idev->lock);
4324 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4325 	send_rs = send_mld &&
4326 		  ipv6_accept_ra(ifp->idev) &&
4327 		  READ_ONCE(ifp->idev->cnf.rtr_solicits) != 0 &&
4328 		  (dev->flags & IFF_LOOPBACK) == 0 &&
4329 		  (dev->type != ARPHRD_TUNNEL) &&
4330 		  !netif_is_team_port(dev);
4331 	read_unlock_bh(&ifp->idev->lock);
4332 
4333 	/* While dad is in progress mld report's source address is in6_addrany.
4334 	 * Resend with proper ll now.
4335 	 */
4336 	if (send_mld)
4337 		ipv6_mc_dad_complete(ifp->idev);
4338 
4339 	/* send unsolicited NA if enabled */
4340 	if (send_na &&
4341 	    (READ_ONCE(ifp->idev->cnf.ndisc_notify) ||
4342 	     READ_ONCE(dev_net(dev)->ipv6.devconf_all->ndisc_notify))) {
4343 		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifp->addr,
4344 			      /*router=*/ !!ifp->idev->cnf.forwarding,
4345 			      /*solicited=*/ false, /*override=*/ true,
4346 			      /*inc_opt=*/ true);
4347 	}
4348 
4349 	if (send_rs) {
4350 		/*
4351 		 *	If a host as already performed a random delay
4352 		 *	[...] as part of DAD [...] there is no need
4353 		 *	to delay again before sending the first RS
4354 		 */
4355 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4356 			return;
4357 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4358 
4359 		write_lock_bh(&ifp->idev->lock);
4360 		spin_lock(&ifp->lock);
4361 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4362 			READ_ONCE(ifp->idev->cnf.rtr_solicit_interval));
4363 		ifp->idev->rs_probes = 1;
4364 		ifp->idev->if_flags |= IF_RS_SENT;
4365 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4366 		spin_unlock(&ifp->lock);
4367 		write_unlock_bh(&ifp->idev->lock);
4368 	}
4369 
4370 	if (bump_id)
4371 		rt_genid_bump_ipv6(dev_net(dev));
4372 
4373 	/* Make sure that a new temporary address will be created
4374 	 * before this temporary address becomes deprecated.
4375 	 */
4376 	if (ifp->flags & IFA_F_TEMPORARY)
4377 		addrconf_verify_rtnl(dev_net(dev));
4378 }
4379 
4380 static void addrconf_dad_run(struct inet6_dev *idev, bool restart)
4381 {
4382 	struct inet6_ifaddr *ifp;
4383 
4384 	read_lock_bh(&idev->lock);
4385 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4386 		spin_lock(&ifp->lock);
4387 		if ((ifp->flags & IFA_F_TENTATIVE &&
4388 		     ifp->state == INET6_IFADDR_STATE_DAD) || restart) {
4389 			if (restart)
4390 				ifp->state = INET6_IFADDR_STATE_PREDAD;
4391 			addrconf_dad_kick(ifp);
4392 		}
4393 		spin_unlock(&ifp->lock);
4394 	}
4395 	read_unlock_bh(&idev->lock);
4396 }
4397 
4398 #ifdef CONFIG_PROC_FS
4399 struct if6_iter_state {
4400 	struct seq_net_private p;
4401 	int bucket;
4402 	int offset;
4403 };
4404 
4405 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4406 {
4407 	struct if6_iter_state *state = seq->private;
4408 	struct net *net = seq_file_net(seq);
4409 	struct inet6_ifaddr *ifa = NULL;
4410 	int p = 0;
4411 
4412 	/* initial bucket if pos is 0 */
4413 	if (pos == 0) {
4414 		state->bucket = 0;
4415 		state->offset = 0;
4416 	}
4417 
4418 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4419 		hlist_for_each_entry_rcu(ifa, &net->ipv6.inet6_addr_lst[state->bucket],
4420 					 addr_lst) {
4421 			/* sync with offset */
4422 			if (p < state->offset) {
4423 				p++;
4424 				continue;
4425 			}
4426 			return ifa;
4427 		}
4428 
4429 		/* prepare for next bucket */
4430 		state->offset = 0;
4431 		p = 0;
4432 	}
4433 	return NULL;
4434 }
4435 
4436 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4437 					 struct inet6_ifaddr *ifa)
4438 {
4439 	struct if6_iter_state *state = seq->private;
4440 	struct net *net = seq_file_net(seq);
4441 
4442 	hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4443 		state->offset++;
4444 		return ifa;
4445 	}
4446 
4447 	state->offset = 0;
4448 	while (++state->bucket < IN6_ADDR_HSIZE) {
4449 		hlist_for_each_entry_rcu(ifa,
4450 				     &net->ipv6.inet6_addr_lst[state->bucket], addr_lst) {
4451 			return ifa;
4452 		}
4453 	}
4454 
4455 	return NULL;
4456 }
4457 
4458 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4459 	__acquires(rcu)
4460 {
4461 	rcu_read_lock();
4462 	return if6_get_first(seq, *pos);
4463 }
4464 
4465 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4466 {
4467 	struct inet6_ifaddr *ifa;
4468 
4469 	ifa = if6_get_next(seq, v);
4470 	++*pos;
4471 	return ifa;
4472 }
4473 
4474 static void if6_seq_stop(struct seq_file *seq, void *v)
4475 	__releases(rcu)
4476 {
4477 	rcu_read_unlock();
4478 }
4479 
4480 static int if6_seq_show(struct seq_file *seq, void *v)
4481 {
4482 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4483 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4484 		   &ifp->addr,
4485 		   ifp->idev->dev->ifindex,
4486 		   ifp->prefix_len,
4487 		   ifp->scope,
4488 		   (u8) ifp->flags,
4489 		   ifp->idev->dev->name);
4490 	return 0;
4491 }
4492 
4493 static const struct seq_operations if6_seq_ops = {
4494 	.start	= if6_seq_start,
4495 	.next	= if6_seq_next,
4496 	.show	= if6_seq_show,
4497 	.stop	= if6_seq_stop,
4498 };
4499 
4500 static int __net_init if6_proc_net_init(struct net *net)
4501 {
4502 	if (!proc_create_net("if_inet6", 0444, net->proc_net, &if6_seq_ops,
4503 			sizeof(struct if6_iter_state)))
4504 		return -ENOMEM;
4505 	return 0;
4506 }
4507 
4508 static void __net_exit if6_proc_net_exit(struct net *net)
4509 {
4510 	remove_proc_entry("if_inet6", net->proc_net);
4511 }
4512 
4513 static struct pernet_operations if6_proc_net_ops = {
4514 	.init = if6_proc_net_init,
4515 	.exit = if6_proc_net_exit,
4516 };
4517 
4518 int __init if6_proc_init(void)
4519 {
4520 	return register_pernet_subsys(&if6_proc_net_ops);
4521 }
4522 
4523 void if6_proc_exit(void)
4524 {
4525 	unregister_pernet_subsys(&if6_proc_net_ops);
4526 }
4527 #endif	/* CONFIG_PROC_FS */
4528 
4529 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4530 /* Check if address is a home address configured on any interface. */
4531 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4532 {
4533 	unsigned int hash = inet6_addr_hash(net, addr);
4534 	struct inet6_ifaddr *ifp = NULL;
4535 	int ret = 0;
4536 
4537 	rcu_read_lock();
4538 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
4539 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4540 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4541 			ret = 1;
4542 			break;
4543 		}
4544 	}
4545 	rcu_read_unlock();
4546 	return ret;
4547 }
4548 #endif
4549 
4550 /* RFC6554 has some algorithm to avoid loops in segment routing by
4551  * checking if the segments contains any of a local interface address.
4552  *
4553  * Quote:
4554  *
4555  * To detect loops in the SRH, a router MUST determine if the SRH
4556  * includes multiple addresses assigned to any interface on that router.
4557  * If such addresses appear more than once and are separated by at least
4558  * one address not assigned to that router.
4559  */
4560 int ipv6_chk_rpl_srh_loop(struct net *net, const struct in6_addr *segs,
4561 			  unsigned char nsegs)
4562 {
4563 	const struct in6_addr *addr;
4564 	int i, ret = 0, found = 0;
4565 	struct inet6_ifaddr *ifp;
4566 	bool separated = false;
4567 	unsigned int hash;
4568 	bool hash_found;
4569 
4570 	rcu_read_lock();
4571 	for (i = 0; i < nsegs; i++) {
4572 		addr = &segs[i];
4573 		hash = inet6_addr_hash(net, addr);
4574 
4575 		hash_found = false;
4576 		hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
4577 
4578 			if (ipv6_addr_equal(&ifp->addr, addr)) {
4579 				hash_found = true;
4580 				break;
4581 			}
4582 		}
4583 
4584 		if (hash_found) {
4585 			if (found > 1 && separated) {
4586 				ret = 1;
4587 				break;
4588 			}
4589 
4590 			separated = false;
4591 			found++;
4592 		} else {
4593 			separated = true;
4594 		}
4595 	}
4596 	rcu_read_unlock();
4597 
4598 	return ret;
4599 }
4600 
4601 /*
4602  *	Periodic address status verification
4603  */
4604 
4605 static void addrconf_verify_rtnl(struct net *net)
4606 {
4607 	unsigned long now, next, next_sec, next_sched;
4608 	struct inet6_ifaddr *ifp;
4609 	int i;
4610 
4611 	ASSERT_RTNL();
4612 
4613 	rcu_read_lock_bh();
4614 	now = jiffies;
4615 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4616 
4617 	cancel_delayed_work(&net->ipv6.addr_chk_work);
4618 
4619 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4620 restart:
4621 		hlist_for_each_entry_rcu_bh(ifp, &net->ipv6.inet6_addr_lst[i], addr_lst) {
4622 			unsigned long age;
4623 
4624 			/* When setting preferred_lft to a value not zero or
4625 			 * infinity, while valid_lft is infinity
4626 			 * IFA_F_PERMANENT has a non-infinity life time.
4627 			 */
4628 			if ((ifp->flags & IFA_F_PERMANENT) &&
4629 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4630 				continue;
4631 
4632 			spin_lock(&ifp->lock);
4633 			/* We try to batch several events at once. */
4634 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4635 
4636 			if ((ifp->flags&IFA_F_TEMPORARY) &&
4637 			    !(ifp->flags&IFA_F_TENTATIVE) &&
4638 			    ifp->prefered_lft != INFINITY_LIFE_TIME &&
4639 			    !ifp->regen_count && ifp->ifpub) {
4640 				/* This is a non-regenerated temporary addr. */
4641 
4642 				unsigned long regen_advance = ipv6_get_regen_advance(ifp->idev);
4643 
4644 				if (age + regen_advance >= ifp->prefered_lft) {
4645 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4646 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4647 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4648 
4649 					ifp->regen_count++;
4650 					in6_ifa_hold(ifp);
4651 					in6_ifa_hold(ifpub);
4652 					spin_unlock(&ifp->lock);
4653 
4654 					spin_lock(&ifpub->lock);
4655 					ifpub->regen_count = 0;
4656 					spin_unlock(&ifpub->lock);
4657 					rcu_read_unlock_bh();
4658 					ipv6_create_tempaddr(ifpub, true);
4659 					in6_ifa_put(ifpub);
4660 					in6_ifa_put(ifp);
4661 					rcu_read_lock_bh();
4662 					goto restart;
4663 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4664 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4665 			}
4666 
4667 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4668 			    age >= ifp->valid_lft) {
4669 				spin_unlock(&ifp->lock);
4670 				in6_ifa_hold(ifp);
4671 				rcu_read_unlock_bh();
4672 				ipv6_del_addr(ifp);
4673 				rcu_read_lock_bh();
4674 				goto restart;
4675 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4676 				spin_unlock(&ifp->lock);
4677 				continue;
4678 			} else if (age >= ifp->prefered_lft) {
4679 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4680 				int deprecate = 0;
4681 
4682 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4683 					deprecate = 1;
4684 					ifp->flags |= IFA_F_DEPRECATED;
4685 				}
4686 
4687 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4688 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4689 					next = ifp->tstamp + ifp->valid_lft * HZ;
4690 
4691 				spin_unlock(&ifp->lock);
4692 
4693 				if (deprecate) {
4694 					in6_ifa_hold(ifp);
4695 
4696 					ipv6_ifa_notify(0, ifp);
4697 					in6_ifa_put(ifp);
4698 					goto restart;
4699 				}
4700 			} else {
4701 				/* ifp->prefered_lft <= ifp->valid_lft */
4702 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4703 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4704 				spin_unlock(&ifp->lock);
4705 			}
4706 		}
4707 	}
4708 
4709 	next_sec = round_jiffies_up(next);
4710 	next_sched = next;
4711 
4712 	/* If rounded timeout is accurate enough, accept it. */
4713 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4714 		next_sched = next_sec;
4715 
4716 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4717 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4718 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4719 
4720 	pr_debug("now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4721 		 now, next, next_sec, next_sched);
4722 	mod_delayed_work(addrconf_wq, &net->ipv6.addr_chk_work, next_sched - now);
4723 	rcu_read_unlock_bh();
4724 }
4725 
4726 static void addrconf_verify_work(struct work_struct *w)
4727 {
4728 	struct net *net = container_of(to_delayed_work(w), struct net,
4729 				       ipv6.addr_chk_work);
4730 
4731 	rtnl_lock();
4732 	addrconf_verify_rtnl(net);
4733 	rtnl_unlock();
4734 }
4735 
4736 static void addrconf_verify(struct net *net)
4737 {
4738 	mod_delayed_work(addrconf_wq, &net->ipv6.addr_chk_work, 0);
4739 }
4740 
4741 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4742 				     struct in6_addr **peer_pfx)
4743 {
4744 	struct in6_addr *pfx = NULL;
4745 
4746 	*peer_pfx = NULL;
4747 
4748 	if (addr)
4749 		pfx = nla_data(addr);
4750 
4751 	if (local) {
4752 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4753 			*peer_pfx = pfx;
4754 		pfx = nla_data(local);
4755 	}
4756 
4757 	return pfx;
4758 }
4759 
4760 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4761 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4762 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4763 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4764 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4765 	[IFA_RT_PRIORITY]	= { .len = sizeof(u32) },
4766 	[IFA_TARGET_NETNSID]	= { .type = NLA_S32 },
4767 	[IFA_PROTO]		= { .type = NLA_U8 },
4768 };
4769 
4770 static int
4771 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4772 		  struct netlink_ext_ack *extack)
4773 {
4774 	struct net *net = sock_net(skb->sk);
4775 	struct ifaddrmsg *ifm;
4776 	struct nlattr *tb[IFA_MAX+1];
4777 	struct in6_addr *pfx, *peer_pfx;
4778 	u32 ifa_flags;
4779 	int err;
4780 
4781 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4782 				     ifa_ipv6_policy, extack);
4783 	if (err < 0)
4784 		return err;
4785 
4786 	ifm = nlmsg_data(nlh);
4787 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4788 	if (!pfx)
4789 		return -EINVAL;
4790 
4791 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4792 
4793 	/* We ignore other flags so far. */
4794 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4795 
4796 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4797 			      ifm->ifa_prefixlen, extack);
4798 }
4799 
4800 static int modify_prefix_route(struct inet6_ifaddr *ifp,
4801 			       unsigned long expires, u32 flags,
4802 			       bool modify_peer)
4803 {
4804 	struct fib6_table *table;
4805 	struct fib6_info *f6i;
4806 	u32 prio;
4807 
4808 	f6i = addrconf_get_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4809 					ifp->prefix_len,
4810 					ifp->idev->dev, 0, RTF_DEFAULT, true);
4811 	if (!f6i)
4812 		return -ENOENT;
4813 
4814 	prio = ifp->rt_priority ? : IP6_RT_PRIO_ADDRCONF;
4815 	if (f6i->fib6_metric != prio) {
4816 		/* delete old one */
4817 		ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
4818 
4819 		/* add new one */
4820 		addrconf_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4821 				      ifp->prefix_len,
4822 				      ifp->rt_priority, ifp->idev->dev,
4823 				      expires, flags, GFP_KERNEL);
4824 	} else {
4825 		table = f6i->fib6_table;
4826 		spin_lock_bh(&table->tb6_lock);
4827 
4828 		if (!(flags & RTF_EXPIRES)) {
4829 			fib6_clean_expires(f6i);
4830 			fib6_remove_gc_list(f6i);
4831 		} else {
4832 			fib6_set_expires(f6i, expires);
4833 			fib6_add_gc_list(f6i);
4834 		}
4835 
4836 		spin_unlock_bh(&table->tb6_lock);
4837 
4838 		fib6_info_release(f6i);
4839 	}
4840 
4841 	return 0;
4842 }
4843 
4844 static int inet6_addr_modify(struct net *net, struct inet6_ifaddr *ifp,
4845 			     struct ifa6_config *cfg)
4846 {
4847 	u32 flags;
4848 	clock_t expires;
4849 	unsigned long timeout;
4850 	bool was_managetempaddr;
4851 	bool had_prefixroute;
4852 	bool new_peer = false;
4853 
4854 	ASSERT_RTNL();
4855 
4856 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
4857 		return -EINVAL;
4858 
4859 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR &&
4860 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4861 		return -EINVAL;
4862 
4863 	if (!(ifp->flags & IFA_F_TENTATIVE) || ifp->flags & IFA_F_DADFAILED)
4864 		cfg->ifa_flags &= ~IFA_F_OPTIMISTIC;
4865 
4866 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
4867 	if (addrconf_finite_timeout(timeout)) {
4868 		expires = jiffies_to_clock_t(timeout * HZ);
4869 		cfg->valid_lft = timeout;
4870 		flags = RTF_EXPIRES;
4871 	} else {
4872 		expires = 0;
4873 		flags = 0;
4874 		cfg->ifa_flags |= IFA_F_PERMANENT;
4875 	}
4876 
4877 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
4878 	if (addrconf_finite_timeout(timeout)) {
4879 		if (timeout == 0)
4880 			cfg->ifa_flags |= IFA_F_DEPRECATED;
4881 		cfg->preferred_lft = timeout;
4882 	}
4883 
4884 	if (cfg->peer_pfx &&
4885 	    memcmp(&ifp->peer_addr, cfg->peer_pfx, sizeof(struct in6_addr))) {
4886 		if (!ipv6_addr_any(&ifp->peer_addr))
4887 			cleanup_prefix_route(ifp, expires, true, true);
4888 		new_peer = true;
4889 	}
4890 
4891 	spin_lock_bh(&ifp->lock);
4892 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4893 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4894 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4895 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4896 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4897 			IFA_F_NOPREFIXROUTE);
4898 	ifp->flags |= cfg->ifa_flags;
4899 	WRITE_ONCE(ifp->tstamp, jiffies);
4900 	WRITE_ONCE(ifp->valid_lft, cfg->valid_lft);
4901 	WRITE_ONCE(ifp->prefered_lft, cfg->preferred_lft);
4902 	WRITE_ONCE(ifp->ifa_proto, cfg->ifa_proto);
4903 
4904 	if (cfg->rt_priority && cfg->rt_priority != ifp->rt_priority)
4905 		WRITE_ONCE(ifp->rt_priority, cfg->rt_priority);
4906 
4907 	if (new_peer)
4908 		ifp->peer_addr = *cfg->peer_pfx;
4909 
4910 	spin_unlock_bh(&ifp->lock);
4911 	if (!(ifp->flags&IFA_F_TENTATIVE))
4912 		ipv6_ifa_notify(0, ifp);
4913 
4914 	if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
4915 		int rc = -ENOENT;
4916 
4917 		if (had_prefixroute)
4918 			rc = modify_prefix_route(ifp, expires, flags, false);
4919 
4920 		/* prefix route could have been deleted; if so restore it */
4921 		if (rc == -ENOENT) {
4922 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4923 					      ifp->rt_priority, ifp->idev->dev,
4924 					      expires, flags, GFP_KERNEL);
4925 		}
4926 
4927 		if (had_prefixroute && !ipv6_addr_any(&ifp->peer_addr))
4928 			rc = modify_prefix_route(ifp, expires, flags, true);
4929 
4930 		if (rc == -ENOENT && !ipv6_addr_any(&ifp->peer_addr)) {
4931 			addrconf_prefix_route(&ifp->peer_addr, ifp->prefix_len,
4932 					      ifp->rt_priority, ifp->idev->dev,
4933 					      expires, flags, GFP_KERNEL);
4934 		}
4935 	} else if (had_prefixroute) {
4936 		enum cleanup_prefix_rt_t action;
4937 		unsigned long rt_expires;
4938 
4939 		write_lock_bh(&ifp->idev->lock);
4940 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4941 		write_unlock_bh(&ifp->idev->lock);
4942 
4943 		if (action != CLEANUP_PREFIX_RT_NOP) {
4944 			cleanup_prefix_route(ifp, rt_expires,
4945 				action == CLEANUP_PREFIX_RT_DEL, false);
4946 		}
4947 	}
4948 
4949 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4950 		if (was_managetempaddr &&
4951 		    !(ifp->flags & IFA_F_MANAGETEMPADDR)) {
4952 			cfg->valid_lft = 0;
4953 			cfg->preferred_lft = 0;
4954 		}
4955 		manage_tempaddrs(ifp->idev, ifp, cfg->valid_lft,
4956 				 cfg->preferred_lft, !was_managetempaddr,
4957 				 jiffies);
4958 	}
4959 
4960 	addrconf_verify_rtnl(net);
4961 
4962 	return 0;
4963 }
4964 
4965 static int
4966 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4967 		  struct netlink_ext_ack *extack)
4968 {
4969 	struct net *net = sock_net(skb->sk);
4970 	struct ifaddrmsg *ifm;
4971 	struct nlattr *tb[IFA_MAX+1];
4972 	struct in6_addr *peer_pfx;
4973 	struct inet6_ifaddr *ifa;
4974 	struct net_device *dev;
4975 	struct inet6_dev *idev;
4976 	struct ifa6_config cfg;
4977 	int err;
4978 
4979 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4980 				     ifa_ipv6_policy, extack);
4981 	if (err < 0)
4982 		return err;
4983 
4984 	memset(&cfg, 0, sizeof(cfg));
4985 
4986 	ifm = nlmsg_data(nlh);
4987 	cfg.pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4988 	if (!cfg.pfx)
4989 		return -EINVAL;
4990 
4991 	cfg.peer_pfx = peer_pfx;
4992 	cfg.plen = ifm->ifa_prefixlen;
4993 	if (tb[IFA_RT_PRIORITY])
4994 		cfg.rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
4995 
4996 	if (tb[IFA_PROTO])
4997 		cfg.ifa_proto = nla_get_u8(tb[IFA_PROTO]);
4998 
4999 	cfg.valid_lft = INFINITY_LIFE_TIME;
5000 	cfg.preferred_lft = INFINITY_LIFE_TIME;
5001 
5002 	if (tb[IFA_CACHEINFO]) {
5003 		struct ifa_cacheinfo *ci;
5004 
5005 		ci = nla_data(tb[IFA_CACHEINFO]);
5006 		cfg.valid_lft = ci->ifa_valid;
5007 		cfg.preferred_lft = ci->ifa_prefered;
5008 	}
5009 
5010 	dev =  __dev_get_by_index(net, ifm->ifa_index);
5011 	if (!dev) {
5012 		NL_SET_ERR_MSG_MOD(extack, "Unable to find the interface");
5013 		return -ENODEV;
5014 	}
5015 
5016 	if (tb[IFA_FLAGS])
5017 		cfg.ifa_flags = nla_get_u32(tb[IFA_FLAGS]);
5018 	else
5019 		cfg.ifa_flags = ifm->ifa_flags;
5020 
5021 	/* We ignore other flags so far. */
5022 	cfg.ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS |
5023 			 IFA_F_MANAGETEMPADDR | IFA_F_NOPREFIXROUTE |
5024 			 IFA_F_MCAUTOJOIN | IFA_F_OPTIMISTIC;
5025 
5026 	idev = ipv6_find_idev(dev);
5027 	if (IS_ERR(idev))
5028 		return PTR_ERR(idev);
5029 
5030 	if (!ipv6_allow_optimistic_dad(net, idev))
5031 		cfg.ifa_flags &= ~IFA_F_OPTIMISTIC;
5032 
5033 	if (cfg.ifa_flags & IFA_F_NODAD &&
5034 	    cfg.ifa_flags & IFA_F_OPTIMISTIC) {
5035 		NL_SET_ERR_MSG(extack, "IFA_F_NODAD and IFA_F_OPTIMISTIC are mutually exclusive");
5036 		return -EINVAL;
5037 	}
5038 
5039 	ifa = ipv6_get_ifaddr(net, cfg.pfx, dev, 1);
5040 	if (!ifa) {
5041 		/*
5042 		 * It would be best to check for !NLM_F_CREATE here but
5043 		 * userspace already relies on not having to provide this.
5044 		 */
5045 		return inet6_addr_add(net, ifm->ifa_index, &cfg, extack);
5046 	}
5047 
5048 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
5049 	    !(nlh->nlmsg_flags & NLM_F_REPLACE)) {
5050 		NL_SET_ERR_MSG_MOD(extack, "address already assigned");
5051 		err = -EEXIST;
5052 	} else {
5053 		err = inet6_addr_modify(net, ifa, &cfg);
5054 	}
5055 
5056 	in6_ifa_put(ifa);
5057 
5058 	return err;
5059 }
5060 
5061 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
5062 			  u8 scope, int ifindex)
5063 {
5064 	struct ifaddrmsg *ifm;
5065 
5066 	ifm = nlmsg_data(nlh);
5067 	ifm->ifa_family = AF_INET6;
5068 	ifm->ifa_prefixlen = prefixlen;
5069 	ifm->ifa_flags = flags;
5070 	ifm->ifa_scope = scope;
5071 	ifm->ifa_index = ifindex;
5072 }
5073 
5074 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
5075 			 unsigned long tstamp, u32 preferred, u32 valid)
5076 {
5077 	struct ifa_cacheinfo ci;
5078 
5079 	ci.cstamp = cstamp_delta(cstamp);
5080 	ci.tstamp = cstamp_delta(tstamp);
5081 	ci.ifa_prefered = preferred;
5082 	ci.ifa_valid = valid;
5083 
5084 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
5085 }
5086 
5087 static inline int rt_scope(int ifa_scope)
5088 {
5089 	if (ifa_scope & IFA_HOST)
5090 		return RT_SCOPE_HOST;
5091 	else if (ifa_scope & IFA_LINK)
5092 		return RT_SCOPE_LINK;
5093 	else if (ifa_scope & IFA_SITE)
5094 		return RT_SCOPE_SITE;
5095 	else
5096 		return RT_SCOPE_UNIVERSE;
5097 }
5098 
5099 static inline int inet6_ifaddr_msgsize(void)
5100 {
5101 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
5102 	       + nla_total_size(16) /* IFA_LOCAL */
5103 	       + nla_total_size(16) /* IFA_ADDRESS */
5104 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
5105 	       + nla_total_size(4)  /* IFA_FLAGS */
5106 	       + nla_total_size(1)  /* IFA_PROTO */
5107 	       + nla_total_size(4)  /* IFA_RT_PRIORITY */;
5108 }
5109 
5110 enum addr_type_t {
5111 	UNICAST_ADDR,
5112 	MULTICAST_ADDR,
5113 	ANYCAST_ADDR,
5114 };
5115 
5116 struct inet6_fill_args {
5117 	u32 portid;
5118 	u32 seq;
5119 	int event;
5120 	unsigned int flags;
5121 	int netnsid;
5122 	int ifindex;
5123 	enum addr_type_t type;
5124 };
5125 
5126 static int inet6_fill_ifaddr(struct sk_buff *skb,
5127 			     const struct inet6_ifaddr *ifa,
5128 			     struct inet6_fill_args *args)
5129 {
5130 	struct nlmsghdr *nlh;
5131 	u32 preferred, valid;
5132 	u32 flags, priority;
5133 	u8 proto;
5134 
5135 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5136 			sizeof(struct ifaddrmsg), args->flags);
5137 	if (!nlh)
5138 		return -EMSGSIZE;
5139 
5140 	flags = READ_ONCE(ifa->flags);
5141 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
5142 		      ifa->idev->dev->ifindex);
5143 
5144 	if (args->netnsid >= 0 &&
5145 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
5146 		goto error;
5147 
5148 	preferred = READ_ONCE(ifa->prefered_lft);
5149 	valid = READ_ONCE(ifa->valid_lft);
5150 
5151 	if (!((flags & IFA_F_PERMANENT) &&
5152 	      (preferred == INFINITY_LIFE_TIME))) {
5153 		if (preferred != INFINITY_LIFE_TIME) {
5154 			long tval = (jiffies - READ_ONCE(ifa->tstamp)) / HZ;
5155 
5156 			if (preferred > tval)
5157 				preferred -= tval;
5158 			else
5159 				preferred = 0;
5160 			if (valid != INFINITY_LIFE_TIME) {
5161 				if (valid > tval)
5162 					valid -= tval;
5163 				else
5164 					valid = 0;
5165 			}
5166 		}
5167 	} else {
5168 		preferred = INFINITY_LIFE_TIME;
5169 		valid = INFINITY_LIFE_TIME;
5170 	}
5171 
5172 	if (!ipv6_addr_any(&ifa->peer_addr)) {
5173 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
5174 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
5175 			goto error;
5176 	} else {
5177 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
5178 			goto error;
5179 	}
5180 
5181 	priority = READ_ONCE(ifa->rt_priority);
5182 	if (priority && nla_put_u32(skb, IFA_RT_PRIORITY, priority))
5183 		goto error;
5184 
5185 	if (put_cacheinfo(skb, ifa->cstamp, READ_ONCE(ifa->tstamp),
5186 			  preferred, valid) < 0)
5187 		goto error;
5188 
5189 	if (nla_put_u32(skb, IFA_FLAGS, flags) < 0)
5190 		goto error;
5191 
5192 	proto = READ_ONCE(ifa->ifa_proto);
5193 	if (proto && nla_put_u8(skb, IFA_PROTO, proto))
5194 		goto error;
5195 
5196 	nlmsg_end(skb, nlh);
5197 	return 0;
5198 
5199 error:
5200 	nlmsg_cancel(skb, nlh);
5201 	return -EMSGSIZE;
5202 }
5203 
5204 static int inet6_fill_ifmcaddr(struct sk_buff *skb,
5205 			       const struct ifmcaddr6 *ifmca,
5206 			       struct inet6_fill_args *args)
5207 {
5208 	int ifindex = ifmca->idev->dev->ifindex;
5209 	u8 scope = RT_SCOPE_UNIVERSE;
5210 	struct nlmsghdr *nlh;
5211 
5212 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
5213 		scope = RT_SCOPE_SITE;
5214 
5215 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5216 			sizeof(struct ifaddrmsg), args->flags);
5217 	if (!nlh)
5218 		return -EMSGSIZE;
5219 
5220 	if (args->netnsid >= 0 &&
5221 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) {
5222 		nlmsg_cancel(skb, nlh);
5223 		return -EMSGSIZE;
5224 	}
5225 
5226 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5227 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
5228 	    put_cacheinfo(skb, ifmca->mca_cstamp, READ_ONCE(ifmca->mca_tstamp),
5229 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5230 		nlmsg_cancel(skb, nlh);
5231 		return -EMSGSIZE;
5232 	}
5233 
5234 	nlmsg_end(skb, nlh);
5235 	return 0;
5236 }
5237 
5238 static int inet6_fill_ifacaddr(struct sk_buff *skb,
5239 			       const struct ifacaddr6 *ifaca,
5240 			       struct inet6_fill_args *args)
5241 {
5242 	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
5243 	int ifindex = dev ? dev->ifindex : 1;
5244 	u8 scope = RT_SCOPE_UNIVERSE;
5245 	struct nlmsghdr *nlh;
5246 
5247 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
5248 		scope = RT_SCOPE_SITE;
5249 
5250 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5251 			sizeof(struct ifaddrmsg), args->flags);
5252 	if (!nlh)
5253 		return -EMSGSIZE;
5254 
5255 	if (args->netnsid >= 0 &&
5256 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) {
5257 		nlmsg_cancel(skb, nlh);
5258 		return -EMSGSIZE;
5259 	}
5260 
5261 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5262 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
5263 	    put_cacheinfo(skb, ifaca->aca_cstamp, READ_ONCE(ifaca->aca_tstamp),
5264 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5265 		nlmsg_cancel(skb, nlh);
5266 		return -EMSGSIZE;
5267 	}
5268 
5269 	nlmsg_end(skb, nlh);
5270 	return 0;
5271 }
5272 
5273 /* called with rcu_read_lock() */
5274 static int in6_dump_addrs(const struct inet6_dev *idev, struct sk_buff *skb,
5275 			  struct netlink_callback *cb, int *s_ip_idx,
5276 			  struct inet6_fill_args *fillargs)
5277 {
5278 	const struct ifmcaddr6 *ifmca;
5279 	const struct ifacaddr6 *ifaca;
5280 	int ip_idx = 0;
5281 	int err = 0;
5282 
5283 	switch (fillargs->type) {
5284 	case UNICAST_ADDR: {
5285 		const struct inet6_ifaddr *ifa;
5286 		fillargs->event = RTM_NEWADDR;
5287 
5288 		/* unicast address incl. temp addr */
5289 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
5290 			if (ip_idx < *s_ip_idx)
5291 				goto next;
5292 			err = inet6_fill_ifaddr(skb, ifa, fillargs);
5293 			if (err < 0)
5294 				break;
5295 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
5296 next:
5297 			ip_idx++;
5298 		}
5299 		break;
5300 	}
5301 	case MULTICAST_ADDR:
5302 		fillargs->event = RTM_GETMULTICAST;
5303 
5304 		/* multicast address */
5305 		for (ifmca = rcu_dereference(idev->mc_list);
5306 		     ifmca;
5307 		     ifmca = rcu_dereference(ifmca->next), ip_idx++) {
5308 			if (ip_idx < *s_ip_idx)
5309 				continue;
5310 			err = inet6_fill_ifmcaddr(skb, ifmca, fillargs);
5311 			if (err < 0)
5312 				break;
5313 		}
5314 		break;
5315 	case ANYCAST_ADDR:
5316 		fillargs->event = RTM_GETANYCAST;
5317 		/* anycast address */
5318 		for (ifaca = rcu_dereference(idev->ac_list); ifaca;
5319 		     ifaca = rcu_dereference(ifaca->aca_next), ip_idx++) {
5320 			if (ip_idx < *s_ip_idx)
5321 				continue;
5322 			err = inet6_fill_ifacaddr(skb, ifaca, fillargs);
5323 			if (err < 0)
5324 				break;
5325 		}
5326 		break;
5327 	default:
5328 		break;
5329 	}
5330 	*s_ip_idx = err ? ip_idx : 0;
5331 	return err;
5332 }
5333 
5334 static int inet6_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
5335 				       struct inet6_fill_args *fillargs,
5336 				       struct net **tgt_net, struct sock *sk,
5337 				       struct netlink_callback *cb)
5338 {
5339 	struct netlink_ext_ack *extack = cb->extack;
5340 	struct nlattr *tb[IFA_MAX+1];
5341 	struct ifaddrmsg *ifm;
5342 	int err, i;
5343 
5344 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5345 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for address dump request");
5346 		return -EINVAL;
5347 	}
5348 
5349 	ifm = nlmsg_data(nlh);
5350 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5351 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address dump request");
5352 		return -EINVAL;
5353 	}
5354 
5355 	fillargs->ifindex = ifm->ifa_index;
5356 	if (fillargs->ifindex) {
5357 		cb->answer_flags |= NLM_F_DUMP_FILTERED;
5358 		fillargs->flags |= NLM_F_DUMP_FILTERED;
5359 	}
5360 
5361 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5362 					    ifa_ipv6_policy, extack);
5363 	if (err < 0)
5364 		return err;
5365 
5366 	for (i = 0; i <= IFA_MAX; ++i) {
5367 		if (!tb[i])
5368 			continue;
5369 
5370 		if (i == IFA_TARGET_NETNSID) {
5371 			struct net *net;
5372 
5373 			fillargs->netnsid = nla_get_s32(tb[i]);
5374 			net = rtnl_get_net_ns_capable(sk, fillargs->netnsid);
5375 			if (IS_ERR(net)) {
5376 				fillargs->netnsid = -1;
5377 				NL_SET_ERR_MSG_MOD(extack, "Invalid target network namespace id");
5378 				return PTR_ERR(net);
5379 			}
5380 			*tgt_net = net;
5381 		} else {
5382 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request");
5383 			return -EINVAL;
5384 		}
5385 	}
5386 
5387 	return 0;
5388 }
5389 
5390 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
5391 			   enum addr_type_t type)
5392 {
5393 	struct net *tgt_net = sock_net(skb->sk);
5394 	const struct nlmsghdr *nlh = cb->nlh;
5395 	struct inet6_fill_args fillargs = {
5396 		.portid = NETLINK_CB(cb->skb).portid,
5397 		.seq = cb->nlh->nlmsg_seq,
5398 		.flags = NLM_F_MULTI,
5399 		.netnsid = -1,
5400 		.type = type,
5401 	};
5402 	struct {
5403 		unsigned long ifindex;
5404 		int ip_idx;
5405 	} *ctx = (void *)cb->ctx;
5406 	struct net_device *dev;
5407 	struct inet6_dev *idev;
5408 	int err = 0;
5409 
5410 	rcu_read_lock();
5411 	if (cb->strict_check) {
5412 		err = inet6_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
5413 						  skb->sk, cb);
5414 		if (err < 0)
5415 			goto done;
5416 
5417 		err = 0;
5418 		if (fillargs.ifindex) {
5419 			err = -ENODEV;
5420 			dev = dev_get_by_index_rcu(tgt_net, fillargs.ifindex);
5421 			if (!dev)
5422 				goto done;
5423 			idev = __in6_dev_get(dev);
5424 			if (idev)
5425 				err = in6_dump_addrs(idev, skb, cb,
5426 						     &ctx->ip_idx,
5427 						     &fillargs);
5428 			goto done;
5429 		}
5430 	}
5431 
5432 	cb->seq = inet6_base_seq(tgt_net);
5433 	for_each_netdev_dump(tgt_net, dev, ctx->ifindex) {
5434 		idev = __in6_dev_get(dev);
5435 		if (!idev)
5436 			continue;
5437 		err = in6_dump_addrs(idev, skb, cb, &ctx->ip_idx,
5438 				     &fillargs);
5439 		if (err < 0)
5440 			goto done;
5441 	}
5442 done:
5443 	rcu_read_unlock();
5444 	if (fillargs.netnsid >= 0)
5445 		put_net(tgt_net);
5446 
5447 	return err;
5448 }
5449 
5450 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
5451 {
5452 	enum addr_type_t type = UNICAST_ADDR;
5453 
5454 	return inet6_dump_addr(skb, cb, type);
5455 }
5456 
5457 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
5458 {
5459 	enum addr_type_t type = MULTICAST_ADDR;
5460 
5461 	return inet6_dump_addr(skb, cb, type);
5462 }
5463 
5464 
5465 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
5466 {
5467 	enum addr_type_t type = ANYCAST_ADDR;
5468 
5469 	return inet6_dump_addr(skb, cb, type);
5470 }
5471 
5472 static int inet6_rtm_valid_getaddr_req(struct sk_buff *skb,
5473 				       const struct nlmsghdr *nlh,
5474 				       struct nlattr **tb,
5475 				       struct netlink_ext_ack *extack)
5476 {
5477 	struct ifaddrmsg *ifm;
5478 	int i, err;
5479 
5480 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5481 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for get address request");
5482 		return -EINVAL;
5483 	}
5484 
5485 	if (!netlink_strict_get_check(skb))
5486 		return nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
5487 					      ifa_ipv6_policy, extack);
5488 
5489 	ifm = nlmsg_data(nlh);
5490 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5491 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get address request");
5492 		return -EINVAL;
5493 	}
5494 
5495 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5496 					    ifa_ipv6_policy, extack);
5497 	if (err)
5498 		return err;
5499 
5500 	for (i = 0; i <= IFA_MAX; i++) {
5501 		if (!tb[i])
5502 			continue;
5503 
5504 		switch (i) {
5505 		case IFA_TARGET_NETNSID:
5506 		case IFA_ADDRESS:
5507 		case IFA_LOCAL:
5508 			break;
5509 		default:
5510 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get address request");
5511 			return -EINVAL;
5512 		}
5513 	}
5514 
5515 	return 0;
5516 }
5517 
5518 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5519 			     struct netlink_ext_ack *extack)
5520 {
5521 	struct net *tgt_net = sock_net(in_skb->sk);
5522 	struct inet6_fill_args fillargs = {
5523 		.portid = NETLINK_CB(in_skb).portid,
5524 		.seq = nlh->nlmsg_seq,
5525 		.event = RTM_NEWADDR,
5526 		.flags = 0,
5527 		.netnsid = -1,
5528 	};
5529 	struct ifaddrmsg *ifm;
5530 	struct nlattr *tb[IFA_MAX+1];
5531 	struct in6_addr *addr = NULL, *peer;
5532 	struct net_device *dev = NULL;
5533 	struct inet6_ifaddr *ifa;
5534 	struct sk_buff *skb;
5535 	int err;
5536 
5537 	err = inet6_rtm_valid_getaddr_req(in_skb, nlh, tb, extack);
5538 	if (err < 0)
5539 		return err;
5540 
5541 	if (tb[IFA_TARGET_NETNSID]) {
5542 		fillargs.netnsid = nla_get_s32(tb[IFA_TARGET_NETNSID]);
5543 
5544 		tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(in_skb).sk,
5545 						  fillargs.netnsid);
5546 		if (IS_ERR(tgt_net))
5547 			return PTR_ERR(tgt_net);
5548 	}
5549 
5550 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
5551 	if (!addr) {
5552 		err = -EINVAL;
5553 		goto errout;
5554 	}
5555 	ifm = nlmsg_data(nlh);
5556 	if (ifm->ifa_index)
5557 		dev = dev_get_by_index(tgt_net, ifm->ifa_index);
5558 
5559 	ifa = ipv6_get_ifaddr(tgt_net, addr, dev, 1);
5560 	if (!ifa) {
5561 		err = -EADDRNOTAVAIL;
5562 		goto errout;
5563 	}
5564 
5565 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
5566 	if (!skb) {
5567 		err = -ENOBUFS;
5568 		goto errout_ifa;
5569 	}
5570 
5571 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5572 	if (err < 0) {
5573 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5574 		WARN_ON(err == -EMSGSIZE);
5575 		kfree_skb(skb);
5576 		goto errout_ifa;
5577 	}
5578 	err = rtnl_unicast(skb, tgt_net, NETLINK_CB(in_skb).portid);
5579 errout_ifa:
5580 	in6_ifa_put(ifa);
5581 errout:
5582 	dev_put(dev);
5583 	if (fillargs.netnsid >= 0)
5584 		put_net(tgt_net);
5585 
5586 	return err;
5587 }
5588 
5589 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
5590 {
5591 	struct sk_buff *skb;
5592 	struct net *net = dev_net(ifa->idev->dev);
5593 	struct inet6_fill_args fillargs = {
5594 		.portid = 0,
5595 		.seq = 0,
5596 		.event = event,
5597 		.flags = 0,
5598 		.netnsid = -1,
5599 	};
5600 	int err = -ENOBUFS;
5601 
5602 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
5603 	if (!skb)
5604 		goto errout;
5605 
5606 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5607 	if (err < 0) {
5608 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5609 		WARN_ON(err == -EMSGSIZE);
5610 		kfree_skb(skb);
5611 		goto errout;
5612 	}
5613 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5614 	return;
5615 errout:
5616 	if (err < 0)
5617 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5618 }
5619 
5620 static void ipv6_store_devconf(const struct ipv6_devconf *cnf,
5621 			       __s32 *array, int bytes)
5622 {
5623 	BUG_ON(bytes < (DEVCONF_MAX * 4));
5624 
5625 	memset(array, 0, bytes);
5626 	array[DEVCONF_FORWARDING] = READ_ONCE(cnf->forwarding);
5627 	array[DEVCONF_HOPLIMIT] = READ_ONCE(cnf->hop_limit);
5628 	array[DEVCONF_MTU6] = READ_ONCE(cnf->mtu6);
5629 	array[DEVCONF_ACCEPT_RA] = READ_ONCE(cnf->accept_ra);
5630 	array[DEVCONF_ACCEPT_REDIRECTS] = READ_ONCE(cnf->accept_redirects);
5631 	array[DEVCONF_AUTOCONF] = READ_ONCE(cnf->autoconf);
5632 	array[DEVCONF_DAD_TRANSMITS] = READ_ONCE(cnf->dad_transmits);
5633 	array[DEVCONF_RTR_SOLICITS] = READ_ONCE(cnf->rtr_solicits);
5634 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5635 		jiffies_to_msecs(READ_ONCE(cnf->rtr_solicit_interval));
5636 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5637 		jiffies_to_msecs(READ_ONCE(cnf->rtr_solicit_max_interval));
5638 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5639 		jiffies_to_msecs(READ_ONCE(cnf->rtr_solicit_delay));
5640 	array[DEVCONF_FORCE_MLD_VERSION] = READ_ONCE(cnf->force_mld_version);
5641 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5642 		jiffies_to_msecs(READ_ONCE(cnf->mldv1_unsolicited_report_interval));
5643 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5644 		jiffies_to_msecs(READ_ONCE(cnf->mldv2_unsolicited_report_interval));
5645 	array[DEVCONF_USE_TEMPADDR] = READ_ONCE(cnf->use_tempaddr);
5646 	array[DEVCONF_TEMP_VALID_LFT] = READ_ONCE(cnf->temp_valid_lft);
5647 	array[DEVCONF_TEMP_PREFERED_LFT] = READ_ONCE(cnf->temp_prefered_lft);
5648 	array[DEVCONF_REGEN_MAX_RETRY] = READ_ONCE(cnf->regen_max_retry);
5649 	array[DEVCONF_MAX_DESYNC_FACTOR] = READ_ONCE(cnf->max_desync_factor);
5650 	array[DEVCONF_MAX_ADDRESSES] = READ_ONCE(cnf->max_addresses);
5651 	array[DEVCONF_ACCEPT_RA_DEFRTR] = READ_ONCE(cnf->accept_ra_defrtr);
5652 	array[DEVCONF_RA_DEFRTR_METRIC] = READ_ONCE(cnf->ra_defrtr_metric);
5653 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] =
5654 		READ_ONCE(cnf->accept_ra_min_hop_limit);
5655 	array[DEVCONF_ACCEPT_RA_PINFO] = READ_ONCE(cnf->accept_ra_pinfo);
5656 #ifdef CONFIG_IPV6_ROUTER_PREF
5657 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = READ_ONCE(cnf->accept_ra_rtr_pref);
5658 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5659 		jiffies_to_msecs(READ_ONCE(cnf->rtr_probe_interval));
5660 #ifdef CONFIG_IPV6_ROUTE_INFO
5661 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] =
5662 		READ_ONCE(cnf->accept_ra_rt_info_min_plen);
5663 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] =
5664 		READ_ONCE(cnf->accept_ra_rt_info_max_plen);
5665 #endif
5666 #endif
5667 	array[DEVCONF_PROXY_NDP] = READ_ONCE(cnf->proxy_ndp);
5668 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] =
5669 		READ_ONCE(cnf->accept_source_route);
5670 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5671 	array[DEVCONF_OPTIMISTIC_DAD] = READ_ONCE(cnf->optimistic_dad);
5672 	array[DEVCONF_USE_OPTIMISTIC] = READ_ONCE(cnf->use_optimistic);
5673 #endif
5674 #ifdef CONFIG_IPV6_MROUTE
5675 	array[DEVCONF_MC_FORWARDING] = atomic_read(&cnf->mc_forwarding);
5676 #endif
5677 	array[DEVCONF_DISABLE_IPV6] = READ_ONCE(cnf->disable_ipv6);
5678 	array[DEVCONF_ACCEPT_DAD] = READ_ONCE(cnf->accept_dad);
5679 	array[DEVCONF_FORCE_TLLAO] = READ_ONCE(cnf->force_tllao);
5680 	array[DEVCONF_NDISC_NOTIFY] = READ_ONCE(cnf->ndisc_notify);
5681 	array[DEVCONF_SUPPRESS_FRAG_NDISC] =
5682 		READ_ONCE(cnf->suppress_frag_ndisc);
5683 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] =
5684 		READ_ONCE(cnf->accept_ra_from_local);
5685 	array[DEVCONF_ACCEPT_RA_MTU] = READ_ONCE(cnf->accept_ra_mtu);
5686 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] =
5687 		READ_ONCE(cnf->ignore_routes_with_linkdown);
5688 	/* we omit DEVCONF_STABLE_SECRET for now */
5689 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = READ_ONCE(cnf->use_oif_addrs_only);
5690 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] =
5691 		READ_ONCE(cnf->drop_unicast_in_l2_multicast);
5692 	array[DEVCONF_DROP_UNSOLICITED_NA] = READ_ONCE(cnf->drop_unsolicited_na);
5693 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = READ_ONCE(cnf->keep_addr_on_down);
5694 	array[DEVCONF_SEG6_ENABLED] = READ_ONCE(cnf->seg6_enabled);
5695 #ifdef CONFIG_IPV6_SEG6_HMAC
5696 	array[DEVCONF_SEG6_REQUIRE_HMAC] = READ_ONCE(cnf->seg6_require_hmac);
5697 #endif
5698 	array[DEVCONF_ENHANCED_DAD] = READ_ONCE(cnf->enhanced_dad);
5699 	array[DEVCONF_ADDR_GEN_MODE] = READ_ONCE(cnf->addr_gen_mode);
5700 	array[DEVCONF_DISABLE_POLICY] = READ_ONCE(cnf->disable_policy);
5701 	array[DEVCONF_NDISC_TCLASS] = READ_ONCE(cnf->ndisc_tclass);
5702 	array[DEVCONF_RPL_SEG_ENABLED] = READ_ONCE(cnf->rpl_seg_enabled);
5703 	array[DEVCONF_IOAM6_ENABLED] = READ_ONCE(cnf->ioam6_enabled);
5704 	array[DEVCONF_IOAM6_ID] = READ_ONCE(cnf->ioam6_id);
5705 	array[DEVCONF_IOAM6_ID_WIDE] = READ_ONCE(cnf->ioam6_id_wide);
5706 	array[DEVCONF_NDISC_EVICT_NOCARRIER] =
5707 		READ_ONCE(cnf->ndisc_evict_nocarrier);
5708 	array[DEVCONF_ACCEPT_UNTRACKED_NA] =
5709 		READ_ONCE(cnf->accept_untracked_na);
5710 	array[DEVCONF_ACCEPT_RA_MIN_LFT] = READ_ONCE(cnf->accept_ra_min_lft);
5711 }
5712 
5713 static inline size_t inet6_ifla6_size(void)
5714 {
5715 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5716 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5717 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5718 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5719 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5720 	     + nla_total_size(sizeof(struct in6_addr)) /* IFLA_INET6_TOKEN */
5721 	     + nla_total_size(1) /* IFLA_INET6_ADDR_GEN_MODE */
5722 	     + nla_total_size(4) /* IFLA_INET6_RA_MTU */
5723 	     + 0;
5724 }
5725 
5726 static inline size_t inet6_if_nlmsg_size(void)
5727 {
5728 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5729 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5730 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5731 	       + nla_total_size(4) /* IFLA_MTU */
5732 	       + nla_total_size(4) /* IFLA_LINK */
5733 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5734 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5735 }
5736 
5737 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5738 					int bytes)
5739 {
5740 	int i;
5741 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5742 	BUG_ON(pad < 0);
5743 
5744 	/* Use put_unaligned() because stats may not be aligned for u64. */
5745 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5746 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5747 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5748 
5749 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5750 }
5751 
5752 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5753 					int bytes, size_t syncpoff)
5754 {
5755 	int i, c;
5756 	u64 buff[IPSTATS_MIB_MAX];
5757 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5758 
5759 	BUG_ON(pad < 0);
5760 
5761 	memset(buff, 0, sizeof(buff));
5762 	buff[0] = IPSTATS_MIB_MAX;
5763 
5764 	for_each_possible_cpu(c) {
5765 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5766 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5767 	}
5768 
5769 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5770 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5771 }
5772 
5773 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5774 			     int bytes)
5775 {
5776 	switch (attrtype) {
5777 	case IFLA_INET6_STATS:
5778 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5779 				     offsetof(struct ipstats_mib, syncp));
5780 		break;
5781 	case IFLA_INET6_ICMP6STATS:
5782 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5783 		break;
5784 	}
5785 }
5786 
5787 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5788 				  u32 ext_filter_mask)
5789 {
5790 	struct ifla_cacheinfo ci;
5791 	struct nlattr *nla;
5792 	u32 ra_mtu;
5793 
5794 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, READ_ONCE(idev->if_flags)))
5795 		goto nla_put_failure;
5796 	ci.max_reasm_len = IPV6_MAXPLEN;
5797 	ci.tstamp = cstamp_delta(READ_ONCE(idev->tstamp));
5798 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5799 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5800 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5801 		goto nla_put_failure;
5802 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5803 	if (!nla)
5804 		goto nla_put_failure;
5805 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5806 
5807 	/* XXX - MC not implemented */
5808 
5809 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5810 		return 0;
5811 
5812 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5813 	if (!nla)
5814 		goto nla_put_failure;
5815 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5816 
5817 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5818 	if (!nla)
5819 		goto nla_put_failure;
5820 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5821 
5822 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5823 	if (!nla)
5824 		goto nla_put_failure;
5825 	read_lock_bh(&idev->lock);
5826 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5827 	read_unlock_bh(&idev->lock);
5828 
5829 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE,
5830 		       READ_ONCE(idev->cnf.addr_gen_mode)))
5831 		goto nla_put_failure;
5832 
5833 	ra_mtu = READ_ONCE(idev->ra_mtu);
5834 	if (ra_mtu && nla_put_u32(skb, IFLA_INET6_RA_MTU, ra_mtu))
5835 		goto nla_put_failure;
5836 
5837 	return 0;
5838 
5839 nla_put_failure:
5840 	return -EMSGSIZE;
5841 }
5842 
5843 static size_t inet6_get_link_af_size(const struct net_device *dev,
5844 				     u32 ext_filter_mask)
5845 {
5846 	if (!__in6_dev_get(dev))
5847 		return 0;
5848 
5849 	return inet6_ifla6_size();
5850 }
5851 
5852 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5853 			      u32 ext_filter_mask)
5854 {
5855 	struct inet6_dev *idev = __in6_dev_get(dev);
5856 
5857 	if (!idev)
5858 		return -ENODATA;
5859 
5860 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5861 		return -EMSGSIZE;
5862 
5863 	return 0;
5864 }
5865 
5866 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token,
5867 			     struct netlink_ext_ack *extack)
5868 {
5869 	struct inet6_ifaddr *ifp;
5870 	struct net_device *dev = idev->dev;
5871 	bool clear_token, update_rs = false;
5872 	struct in6_addr ll_addr;
5873 
5874 	ASSERT_RTNL();
5875 
5876 	if (!token)
5877 		return -EINVAL;
5878 
5879 	if (dev->flags & IFF_LOOPBACK) {
5880 		NL_SET_ERR_MSG_MOD(extack, "Device is loopback");
5881 		return -EINVAL;
5882 	}
5883 
5884 	if (dev->flags & IFF_NOARP) {
5885 		NL_SET_ERR_MSG_MOD(extack,
5886 				   "Device does not do neighbour discovery");
5887 		return -EINVAL;
5888 	}
5889 
5890 	if (!ipv6_accept_ra(idev)) {
5891 		NL_SET_ERR_MSG_MOD(extack,
5892 				   "Router advertisement is disabled on device");
5893 		return -EINVAL;
5894 	}
5895 
5896 	if (READ_ONCE(idev->cnf.rtr_solicits) == 0) {
5897 		NL_SET_ERR_MSG(extack,
5898 			       "Router solicitation is disabled on device");
5899 		return -EINVAL;
5900 	}
5901 
5902 	write_lock_bh(&idev->lock);
5903 
5904 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5905 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5906 
5907 	write_unlock_bh(&idev->lock);
5908 
5909 	clear_token = ipv6_addr_any(token);
5910 	if (clear_token)
5911 		goto update_lft;
5912 
5913 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5914 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5915 			     IFA_F_OPTIMISTIC)) {
5916 		/* If we're not ready, then normal ifup will take care
5917 		 * of this. Otherwise, we need to request our rs here.
5918 		 */
5919 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5920 		update_rs = true;
5921 	}
5922 
5923 update_lft:
5924 	write_lock_bh(&idev->lock);
5925 
5926 	if (update_rs) {
5927 		idev->if_flags |= IF_RS_SENT;
5928 		idev->rs_interval = rfc3315_s14_backoff_init(
5929 			READ_ONCE(idev->cnf.rtr_solicit_interval));
5930 		idev->rs_probes = 1;
5931 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5932 	}
5933 
5934 	/* Well, that's kinda nasty ... */
5935 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5936 		spin_lock(&ifp->lock);
5937 		if (ifp->tokenized) {
5938 			ifp->valid_lft = 0;
5939 			ifp->prefered_lft = 0;
5940 		}
5941 		spin_unlock(&ifp->lock);
5942 	}
5943 
5944 	write_unlock_bh(&idev->lock);
5945 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5946 	addrconf_verify_rtnl(dev_net(dev));
5947 	return 0;
5948 }
5949 
5950 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5951 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5952 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5953 	[IFLA_INET6_RA_MTU]		= { .type = NLA_REJECT,
5954 					    .reject_message =
5955 						"IFLA_INET6_RA_MTU can not be set" },
5956 };
5957 
5958 static int check_addr_gen_mode(int mode)
5959 {
5960 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5961 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5962 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5963 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5964 		return -EINVAL;
5965 	return 1;
5966 }
5967 
5968 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5969 				int mode)
5970 {
5971 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5972 	    !idev->cnf.stable_secret.initialized &&
5973 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5974 		return -EINVAL;
5975 	return 1;
5976 }
5977 
5978 static int inet6_validate_link_af(const struct net_device *dev,
5979 				  const struct nlattr *nla,
5980 				  struct netlink_ext_ack *extack)
5981 {
5982 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5983 	struct inet6_dev *idev = NULL;
5984 	int err;
5985 
5986 	if (dev) {
5987 		idev = __in6_dev_get(dev);
5988 		if (!idev)
5989 			return -EAFNOSUPPORT;
5990 	}
5991 
5992 	err = nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla,
5993 					  inet6_af_policy, extack);
5994 	if (err)
5995 		return err;
5996 
5997 	if (!tb[IFLA_INET6_TOKEN] && !tb[IFLA_INET6_ADDR_GEN_MODE])
5998 		return -EINVAL;
5999 
6000 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
6001 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
6002 
6003 		if (check_addr_gen_mode(mode) < 0)
6004 			return -EINVAL;
6005 		if (dev && check_stable_privacy(idev, dev_net(dev), mode) < 0)
6006 			return -EINVAL;
6007 	}
6008 
6009 	return 0;
6010 }
6011 
6012 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla,
6013 			     struct netlink_ext_ack *extack)
6014 {
6015 	struct inet6_dev *idev = __in6_dev_get(dev);
6016 	struct nlattr *tb[IFLA_INET6_MAX + 1];
6017 	int err;
6018 
6019 	if (!idev)
6020 		return -EAFNOSUPPORT;
6021 
6022 	if (nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
6023 		return -EINVAL;
6024 
6025 	if (tb[IFLA_INET6_TOKEN]) {
6026 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]),
6027 					extack);
6028 		if (err)
6029 			return err;
6030 	}
6031 
6032 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
6033 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
6034 
6035 		WRITE_ONCE(idev->cnf.addr_gen_mode, mode);
6036 	}
6037 
6038 	return 0;
6039 }
6040 
6041 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
6042 			     u32 portid, u32 seq, int event, unsigned int flags)
6043 {
6044 	struct net_device *dev = idev->dev;
6045 	struct ifinfomsg *hdr;
6046 	struct nlmsghdr *nlh;
6047 	int ifindex, iflink;
6048 	void *protoinfo;
6049 
6050 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
6051 	if (!nlh)
6052 		return -EMSGSIZE;
6053 
6054 	hdr = nlmsg_data(nlh);
6055 	hdr->ifi_family = AF_INET6;
6056 	hdr->__ifi_pad = 0;
6057 	hdr->ifi_type = dev->type;
6058 	ifindex = READ_ONCE(dev->ifindex);
6059 	hdr->ifi_index = ifindex;
6060 	hdr->ifi_flags = dev_get_flags(dev);
6061 	hdr->ifi_change = 0;
6062 
6063 	iflink = dev_get_iflink(dev);
6064 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
6065 	    (dev->addr_len &&
6066 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
6067 	    nla_put_u32(skb, IFLA_MTU, READ_ONCE(dev->mtu)) ||
6068 	    (ifindex != iflink &&
6069 	     nla_put_u32(skb, IFLA_LINK, iflink)) ||
6070 	    nla_put_u8(skb, IFLA_OPERSTATE,
6071 		       netif_running(dev) ? READ_ONCE(dev->operstate) : IF_OPER_DOWN))
6072 		goto nla_put_failure;
6073 	protoinfo = nla_nest_start_noflag(skb, IFLA_PROTINFO);
6074 	if (!protoinfo)
6075 		goto nla_put_failure;
6076 
6077 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
6078 		goto nla_put_failure;
6079 
6080 	nla_nest_end(skb, protoinfo);
6081 	nlmsg_end(skb, nlh);
6082 	return 0;
6083 
6084 nla_put_failure:
6085 	nlmsg_cancel(skb, nlh);
6086 	return -EMSGSIZE;
6087 }
6088 
6089 static int inet6_valid_dump_ifinfo(const struct nlmsghdr *nlh,
6090 				   struct netlink_ext_ack *extack)
6091 {
6092 	struct ifinfomsg *ifm;
6093 
6094 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
6095 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for link dump request");
6096 		return -EINVAL;
6097 	}
6098 
6099 	if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
6100 		NL_SET_ERR_MSG_MOD(extack, "Invalid data after header");
6101 		return -EINVAL;
6102 	}
6103 
6104 	ifm = nlmsg_data(nlh);
6105 	if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
6106 	    ifm->ifi_change || ifm->ifi_index) {
6107 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for dump request");
6108 		return -EINVAL;
6109 	}
6110 
6111 	return 0;
6112 }
6113 
6114 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
6115 {
6116 	struct net *net = sock_net(skb->sk);
6117 	struct {
6118 		unsigned long ifindex;
6119 	} *ctx = (void *)cb->ctx;
6120 	struct net_device *dev;
6121 	struct inet6_dev *idev;
6122 	int err;
6123 
6124 	/* only requests using strict checking can pass data to
6125 	 * influence the dump
6126 	 */
6127 	if (cb->strict_check) {
6128 		err = inet6_valid_dump_ifinfo(cb->nlh, cb->extack);
6129 
6130 		if (err < 0)
6131 			return err;
6132 	}
6133 
6134 	err = 0;
6135 	rcu_read_lock();
6136 	for_each_netdev_dump(net, dev, ctx->ifindex) {
6137 		idev = __in6_dev_get(dev);
6138 		if (!idev)
6139 			continue;
6140 		err = inet6_fill_ifinfo(skb, idev,
6141 					NETLINK_CB(cb->skb).portid,
6142 					cb->nlh->nlmsg_seq,
6143 					RTM_NEWLINK, NLM_F_MULTI);
6144 		if (err < 0)
6145 			break;
6146 	}
6147 	rcu_read_unlock();
6148 
6149 	return err;
6150 }
6151 
6152 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
6153 {
6154 	struct sk_buff *skb;
6155 	struct net *net = dev_net(idev->dev);
6156 	int err = -ENOBUFS;
6157 
6158 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
6159 	if (!skb)
6160 		goto errout;
6161 
6162 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
6163 	if (err < 0) {
6164 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
6165 		WARN_ON(err == -EMSGSIZE);
6166 		kfree_skb(skb);
6167 		goto errout;
6168 	}
6169 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
6170 	return;
6171 errout:
6172 	if (err < 0)
6173 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
6174 }
6175 
6176 static inline size_t inet6_prefix_nlmsg_size(void)
6177 {
6178 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
6179 	       + nla_total_size(sizeof(struct in6_addr))
6180 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
6181 }
6182 
6183 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
6184 			     struct prefix_info *pinfo, u32 portid, u32 seq,
6185 			     int event, unsigned int flags)
6186 {
6187 	struct prefixmsg *pmsg;
6188 	struct nlmsghdr *nlh;
6189 	struct prefix_cacheinfo	ci;
6190 
6191 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
6192 	if (!nlh)
6193 		return -EMSGSIZE;
6194 
6195 	pmsg = nlmsg_data(nlh);
6196 	pmsg->prefix_family = AF_INET6;
6197 	pmsg->prefix_pad1 = 0;
6198 	pmsg->prefix_pad2 = 0;
6199 	pmsg->prefix_ifindex = idev->dev->ifindex;
6200 	pmsg->prefix_len = pinfo->prefix_len;
6201 	pmsg->prefix_type = pinfo->type;
6202 	pmsg->prefix_pad3 = 0;
6203 	pmsg->prefix_flags = pinfo->flags;
6204 
6205 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
6206 		goto nla_put_failure;
6207 	ci.preferred_time = ntohl(pinfo->prefered);
6208 	ci.valid_time = ntohl(pinfo->valid);
6209 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
6210 		goto nla_put_failure;
6211 	nlmsg_end(skb, nlh);
6212 	return 0;
6213 
6214 nla_put_failure:
6215 	nlmsg_cancel(skb, nlh);
6216 	return -EMSGSIZE;
6217 }
6218 
6219 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
6220 			 struct prefix_info *pinfo)
6221 {
6222 	struct sk_buff *skb;
6223 	struct net *net = dev_net(idev->dev);
6224 	int err = -ENOBUFS;
6225 
6226 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
6227 	if (!skb)
6228 		goto errout;
6229 
6230 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
6231 	if (err < 0) {
6232 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
6233 		WARN_ON(err == -EMSGSIZE);
6234 		kfree_skb(skb);
6235 		goto errout;
6236 	}
6237 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
6238 	return;
6239 errout:
6240 	if (err < 0)
6241 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
6242 }
6243 
6244 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6245 {
6246 	struct net *net = dev_net(ifp->idev->dev);
6247 
6248 	if (event)
6249 		ASSERT_RTNL();
6250 
6251 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
6252 
6253 	switch (event) {
6254 	case RTM_NEWADDR:
6255 		/*
6256 		 * If the address was optimistic we inserted the route at the
6257 		 * start of our DAD process, so we don't need to do it again.
6258 		 * If the device was taken down in the middle of the DAD
6259 		 * cycle there is a race where we could get here without a
6260 		 * host route, so nothing to insert. That will be fixed when
6261 		 * the device is brought up.
6262 		 */
6263 		if (ifp->rt && !rcu_access_pointer(ifp->rt->fib6_node)) {
6264 			ip6_ins_rt(net, ifp->rt);
6265 		} else if (!ifp->rt && (ifp->idev->dev->flags & IFF_UP)) {
6266 			pr_warn("BUG: Address %pI6c on device %s is missing its host route.\n",
6267 				&ifp->addr, ifp->idev->dev->name);
6268 		}
6269 
6270 		if (ifp->idev->cnf.forwarding)
6271 			addrconf_join_anycast(ifp);
6272 		if (!ipv6_addr_any(&ifp->peer_addr))
6273 			addrconf_prefix_route(&ifp->peer_addr, 128,
6274 					      ifp->rt_priority, ifp->idev->dev,
6275 					      0, 0, GFP_ATOMIC);
6276 		break;
6277 	case RTM_DELADDR:
6278 		if (ifp->idev->cnf.forwarding)
6279 			addrconf_leave_anycast(ifp);
6280 		addrconf_leave_solict(ifp->idev, &ifp->addr);
6281 		if (!ipv6_addr_any(&ifp->peer_addr)) {
6282 			struct fib6_info *rt;
6283 
6284 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
6285 						       ifp->idev->dev, 0, 0,
6286 						       false);
6287 			if (rt)
6288 				ip6_del_rt(net, rt, false);
6289 		}
6290 		if (ifp->rt) {
6291 			ip6_del_rt(net, ifp->rt, false);
6292 			ifp->rt = NULL;
6293 		}
6294 		rt_genid_bump_ipv6(net);
6295 		break;
6296 	}
6297 	atomic_inc(&net->ipv6.dev_addr_genid);
6298 }
6299 
6300 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6301 {
6302 	if (likely(ifp->idev->dead == 0))
6303 		__ipv6_ifa_notify(event, ifp);
6304 }
6305 
6306 #ifdef CONFIG_SYSCTL
6307 
6308 static int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
6309 		void *buffer, size_t *lenp, loff_t *ppos)
6310 {
6311 	int *valp = ctl->data;
6312 	int val = *valp;
6313 	loff_t pos = *ppos;
6314 	struct ctl_table lctl;
6315 	int ret;
6316 
6317 	/*
6318 	 * ctl->data points to idev->cnf.forwarding, we should
6319 	 * not modify it until we get the rtnl lock.
6320 	 */
6321 	lctl = *ctl;
6322 	lctl.data = &val;
6323 
6324 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6325 
6326 	if (write)
6327 		ret = addrconf_fixup_forwarding(ctl, valp, val);
6328 	if (ret)
6329 		*ppos = pos;
6330 	return ret;
6331 }
6332 
6333 static int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
6334 		void *buffer, size_t *lenp, loff_t *ppos)
6335 {
6336 	struct inet6_dev *idev = ctl->extra1;
6337 	int min_mtu = IPV6_MIN_MTU;
6338 	struct ctl_table lctl;
6339 
6340 	lctl = *ctl;
6341 	lctl.extra1 = &min_mtu;
6342 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
6343 
6344 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
6345 }
6346 
6347 static void dev_disable_change(struct inet6_dev *idev)
6348 {
6349 	struct netdev_notifier_info info;
6350 
6351 	if (!idev || !idev->dev)
6352 		return;
6353 
6354 	netdev_notifier_info_init(&info, idev->dev);
6355 	if (idev->cnf.disable_ipv6)
6356 		addrconf_notify(NULL, NETDEV_DOWN, &info);
6357 	else
6358 		addrconf_notify(NULL, NETDEV_UP, &info);
6359 }
6360 
6361 static void addrconf_disable_change(struct net *net, __s32 newf)
6362 {
6363 	struct net_device *dev;
6364 	struct inet6_dev *idev;
6365 
6366 	for_each_netdev(net, dev) {
6367 		idev = __in6_dev_get(dev);
6368 		if (idev) {
6369 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
6370 
6371 			WRITE_ONCE(idev->cnf.disable_ipv6, newf);
6372 			if (changed)
6373 				dev_disable_change(idev);
6374 		}
6375 	}
6376 }
6377 
6378 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
6379 {
6380 	struct net *net = (struct net *)table->extra2;
6381 	int old;
6382 
6383 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
6384 		WRITE_ONCE(*p, newf);
6385 		return 0;
6386 	}
6387 
6388 	if (!rtnl_trylock())
6389 		return restart_syscall();
6390 
6391 	old = *p;
6392 	WRITE_ONCE(*p, newf);
6393 
6394 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
6395 		WRITE_ONCE(net->ipv6.devconf_dflt->disable_ipv6, newf);
6396 		addrconf_disable_change(net, newf);
6397 	} else if ((!newf) ^ (!old))
6398 		dev_disable_change((struct inet6_dev *)table->extra1);
6399 
6400 	rtnl_unlock();
6401 	return 0;
6402 }
6403 
6404 static int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
6405 		void *buffer, size_t *lenp, loff_t *ppos)
6406 {
6407 	int *valp = ctl->data;
6408 	int val = *valp;
6409 	loff_t pos = *ppos;
6410 	struct ctl_table lctl;
6411 	int ret;
6412 
6413 	/*
6414 	 * ctl->data points to idev->cnf.disable_ipv6, we should
6415 	 * not modify it until we get the rtnl lock.
6416 	 */
6417 	lctl = *ctl;
6418 	lctl.data = &val;
6419 
6420 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6421 
6422 	if (write)
6423 		ret = addrconf_disable_ipv6(ctl, valp, val);
6424 	if (ret)
6425 		*ppos = pos;
6426 	return ret;
6427 }
6428 
6429 static int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
6430 		void *buffer, size_t *lenp, loff_t *ppos)
6431 {
6432 	int *valp = ctl->data;
6433 	int ret;
6434 	int old, new;
6435 
6436 	old = *valp;
6437 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
6438 	new = *valp;
6439 
6440 	if (write && old != new) {
6441 		struct net *net = ctl->extra2;
6442 
6443 		if (!rtnl_trylock())
6444 			return restart_syscall();
6445 
6446 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
6447 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6448 						     NETCONFA_PROXY_NEIGH,
6449 						     NETCONFA_IFINDEX_DEFAULT,
6450 						     net->ipv6.devconf_dflt);
6451 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
6452 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6453 						     NETCONFA_PROXY_NEIGH,
6454 						     NETCONFA_IFINDEX_ALL,
6455 						     net->ipv6.devconf_all);
6456 		else {
6457 			struct inet6_dev *idev = ctl->extra1;
6458 
6459 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6460 						     NETCONFA_PROXY_NEIGH,
6461 						     idev->dev->ifindex,
6462 						     &idev->cnf);
6463 		}
6464 		rtnl_unlock();
6465 	}
6466 
6467 	return ret;
6468 }
6469 
6470 static int addrconf_sysctl_addr_gen_mode(struct ctl_table *ctl, int write,
6471 					 void *buffer, size_t *lenp,
6472 					 loff_t *ppos)
6473 {
6474 	int ret = 0;
6475 	u32 new_val;
6476 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
6477 	struct net *net = (struct net *)ctl->extra2;
6478 	struct ctl_table tmp = {
6479 		.data = &new_val,
6480 		.maxlen = sizeof(new_val),
6481 		.mode = ctl->mode,
6482 	};
6483 
6484 	if (!rtnl_trylock())
6485 		return restart_syscall();
6486 
6487 	new_val = *((u32 *)ctl->data);
6488 
6489 	ret = proc_douintvec(&tmp, write, buffer, lenp, ppos);
6490 	if (ret != 0)
6491 		goto out;
6492 
6493 	if (write) {
6494 		if (check_addr_gen_mode(new_val) < 0) {
6495 			ret = -EINVAL;
6496 			goto out;
6497 		}
6498 
6499 		if (idev) {
6500 			if (check_stable_privacy(idev, net, new_val) < 0) {
6501 				ret = -EINVAL;
6502 				goto out;
6503 			}
6504 
6505 			if (idev->cnf.addr_gen_mode != new_val) {
6506 				WRITE_ONCE(idev->cnf.addr_gen_mode, new_val);
6507 				addrconf_init_auto_addrs(idev->dev);
6508 			}
6509 		} else if (&net->ipv6.devconf_all->addr_gen_mode == ctl->data) {
6510 			struct net_device *dev;
6511 
6512 			WRITE_ONCE(net->ipv6.devconf_dflt->addr_gen_mode, new_val);
6513 			for_each_netdev(net, dev) {
6514 				idev = __in6_dev_get(dev);
6515 				if (idev &&
6516 				    idev->cnf.addr_gen_mode != new_val) {
6517 					WRITE_ONCE(idev->cnf.addr_gen_mode,
6518 						  new_val);
6519 					addrconf_init_auto_addrs(idev->dev);
6520 				}
6521 			}
6522 		}
6523 
6524 		WRITE_ONCE(*((u32 *)ctl->data), new_val);
6525 	}
6526 
6527 out:
6528 	rtnl_unlock();
6529 
6530 	return ret;
6531 }
6532 
6533 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
6534 					 void *buffer, size_t *lenp,
6535 					 loff_t *ppos)
6536 {
6537 	int err;
6538 	struct in6_addr addr;
6539 	char str[IPV6_MAX_STRLEN];
6540 	struct ctl_table lctl = *ctl;
6541 	struct net *net = ctl->extra2;
6542 	struct ipv6_stable_secret *secret = ctl->data;
6543 
6544 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
6545 		return -EIO;
6546 
6547 	lctl.maxlen = IPV6_MAX_STRLEN;
6548 	lctl.data = str;
6549 
6550 	if (!rtnl_trylock())
6551 		return restart_syscall();
6552 
6553 	if (!write && !secret->initialized) {
6554 		err = -EIO;
6555 		goto out;
6556 	}
6557 
6558 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
6559 	if (err >= sizeof(str)) {
6560 		err = -EIO;
6561 		goto out;
6562 	}
6563 
6564 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
6565 	if (err || !write)
6566 		goto out;
6567 
6568 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
6569 		err = -EIO;
6570 		goto out;
6571 	}
6572 
6573 	secret->initialized = true;
6574 	secret->secret = addr;
6575 
6576 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
6577 		struct net_device *dev;
6578 
6579 		for_each_netdev(net, dev) {
6580 			struct inet6_dev *idev = __in6_dev_get(dev);
6581 
6582 			if (idev) {
6583 				WRITE_ONCE(idev->cnf.addr_gen_mode,
6584 					   IN6_ADDR_GEN_MODE_STABLE_PRIVACY);
6585 			}
6586 		}
6587 	} else {
6588 		struct inet6_dev *idev = ctl->extra1;
6589 
6590 		WRITE_ONCE(idev->cnf.addr_gen_mode,
6591 			   IN6_ADDR_GEN_MODE_STABLE_PRIVACY);
6592 	}
6593 
6594 out:
6595 	rtnl_unlock();
6596 
6597 	return err;
6598 }
6599 
6600 static
6601 int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
6602 						int write, void *buffer,
6603 						size_t *lenp,
6604 						loff_t *ppos)
6605 {
6606 	int *valp = ctl->data;
6607 	int val = *valp;
6608 	loff_t pos = *ppos;
6609 	struct ctl_table lctl;
6610 	int ret;
6611 
6612 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
6613 	 * we should not modify it until we get the rtnl lock.
6614 	 */
6615 	lctl = *ctl;
6616 	lctl.data = &val;
6617 
6618 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6619 
6620 	if (write)
6621 		ret = addrconf_fixup_linkdown(ctl, valp, val);
6622 	if (ret)
6623 		*ppos = pos;
6624 	return ret;
6625 }
6626 
6627 static
6628 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
6629 {
6630 	if (rt) {
6631 		if (action)
6632 			rt->dst.flags |= DST_NOPOLICY;
6633 		else
6634 			rt->dst.flags &= ~DST_NOPOLICY;
6635 	}
6636 }
6637 
6638 static
6639 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
6640 {
6641 	struct inet6_ifaddr *ifa;
6642 
6643 	read_lock_bh(&idev->lock);
6644 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
6645 		spin_lock(&ifa->lock);
6646 		if (ifa->rt) {
6647 			/* host routes only use builtin fib6_nh */
6648 			struct fib6_nh *nh = ifa->rt->fib6_nh;
6649 			int cpu;
6650 
6651 			rcu_read_lock();
6652 			ifa->rt->dst_nopolicy = val ? true : false;
6653 			if (nh->rt6i_pcpu) {
6654 				for_each_possible_cpu(cpu) {
6655 					struct rt6_info **rtp;
6656 
6657 					rtp = per_cpu_ptr(nh->rt6i_pcpu, cpu);
6658 					addrconf_set_nopolicy(*rtp, val);
6659 				}
6660 			}
6661 			rcu_read_unlock();
6662 		}
6663 		spin_unlock(&ifa->lock);
6664 	}
6665 	read_unlock_bh(&idev->lock);
6666 }
6667 
6668 static
6669 int addrconf_disable_policy(struct ctl_table *ctl, int *valp, int val)
6670 {
6671 	struct net *net = (struct net *)ctl->extra2;
6672 	struct inet6_dev *idev;
6673 
6674 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
6675 		WRITE_ONCE(*valp, val);
6676 		return 0;
6677 	}
6678 
6679 	if (!rtnl_trylock())
6680 		return restart_syscall();
6681 
6682 	WRITE_ONCE(*valp, val);
6683 
6684 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
6685 		struct net_device *dev;
6686 
6687 		for_each_netdev(net, dev) {
6688 			idev = __in6_dev_get(dev);
6689 			if (idev)
6690 				addrconf_disable_policy_idev(idev, val);
6691 		}
6692 	} else {
6693 		idev = (struct inet6_dev *)ctl->extra1;
6694 		addrconf_disable_policy_idev(idev, val);
6695 	}
6696 
6697 	rtnl_unlock();
6698 	return 0;
6699 }
6700 
6701 static int addrconf_sysctl_disable_policy(struct ctl_table *ctl, int write,
6702 				   void *buffer, size_t *lenp, loff_t *ppos)
6703 {
6704 	int *valp = ctl->data;
6705 	int val = *valp;
6706 	loff_t pos = *ppos;
6707 	struct ctl_table lctl;
6708 	int ret;
6709 
6710 	lctl = *ctl;
6711 	lctl.data = &val;
6712 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6713 
6714 	if (write && (*valp != val))
6715 		ret = addrconf_disable_policy(ctl, valp, val);
6716 
6717 	if (ret)
6718 		*ppos = pos;
6719 
6720 	return ret;
6721 }
6722 
6723 static int minus_one = -1;
6724 static const int two_five_five = 255;
6725 static u32 ioam6_if_id_max = U16_MAX;
6726 
6727 static const struct ctl_table addrconf_sysctl[] = {
6728 	{
6729 		.procname	= "forwarding",
6730 		.data		= &ipv6_devconf.forwarding,
6731 		.maxlen		= sizeof(int),
6732 		.mode		= 0644,
6733 		.proc_handler	= addrconf_sysctl_forward,
6734 	},
6735 	{
6736 		.procname	= "hop_limit",
6737 		.data		= &ipv6_devconf.hop_limit,
6738 		.maxlen		= sizeof(int),
6739 		.mode		= 0644,
6740 		.proc_handler	= proc_dointvec_minmax,
6741 		.extra1		= (void *)SYSCTL_ONE,
6742 		.extra2		= (void *)&two_five_five,
6743 	},
6744 	{
6745 		.procname	= "mtu",
6746 		.data		= &ipv6_devconf.mtu6,
6747 		.maxlen		= sizeof(int),
6748 		.mode		= 0644,
6749 		.proc_handler	= addrconf_sysctl_mtu,
6750 	},
6751 	{
6752 		.procname	= "accept_ra",
6753 		.data		= &ipv6_devconf.accept_ra,
6754 		.maxlen		= sizeof(int),
6755 		.mode		= 0644,
6756 		.proc_handler	= proc_dointvec,
6757 	},
6758 	{
6759 		.procname	= "accept_redirects",
6760 		.data		= &ipv6_devconf.accept_redirects,
6761 		.maxlen		= sizeof(int),
6762 		.mode		= 0644,
6763 		.proc_handler	= proc_dointvec,
6764 	},
6765 	{
6766 		.procname	= "autoconf",
6767 		.data		= &ipv6_devconf.autoconf,
6768 		.maxlen		= sizeof(int),
6769 		.mode		= 0644,
6770 		.proc_handler	= proc_dointvec,
6771 	},
6772 	{
6773 		.procname	= "dad_transmits",
6774 		.data		= &ipv6_devconf.dad_transmits,
6775 		.maxlen		= sizeof(int),
6776 		.mode		= 0644,
6777 		.proc_handler	= proc_dointvec,
6778 	},
6779 	{
6780 		.procname	= "router_solicitations",
6781 		.data		= &ipv6_devconf.rtr_solicits,
6782 		.maxlen		= sizeof(int),
6783 		.mode		= 0644,
6784 		.proc_handler	= proc_dointvec_minmax,
6785 		.extra1		= &minus_one,
6786 	},
6787 	{
6788 		.procname	= "router_solicitation_interval",
6789 		.data		= &ipv6_devconf.rtr_solicit_interval,
6790 		.maxlen		= sizeof(int),
6791 		.mode		= 0644,
6792 		.proc_handler	= proc_dointvec_jiffies,
6793 	},
6794 	{
6795 		.procname	= "router_solicitation_max_interval",
6796 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6797 		.maxlen		= sizeof(int),
6798 		.mode		= 0644,
6799 		.proc_handler	= proc_dointvec_jiffies,
6800 	},
6801 	{
6802 		.procname	= "router_solicitation_delay",
6803 		.data		= &ipv6_devconf.rtr_solicit_delay,
6804 		.maxlen		= sizeof(int),
6805 		.mode		= 0644,
6806 		.proc_handler	= proc_dointvec_jiffies,
6807 	},
6808 	{
6809 		.procname	= "force_mld_version",
6810 		.data		= &ipv6_devconf.force_mld_version,
6811 		.maxlen		= sizeof(int),
6812 		.mode		= 0644,
6813 		.proc_handler	= proc_dointvec,
6814 	},
6815 	{
6816 		.procname	= "mldv1_unsolicited_report_interval",
6817 		.data		=
6818 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6819 		.maxlen		= sizeof(int),
6820 		.mode		= 0644,
6821 		.proc_handler	= proc_dointvec_ms_jiffies,
6822 	},
6823 	{
6824 		.procname	= "mldv2_unsolicited_report_interval",
6825 		.data		=
6826 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6827 		.maxlen		= sizeof(int),
6828 		.mode		= 0644,
6829 		.proc_handler	= proc_dointvec_ms_jiffies,
6830 	},
6831 	{
6832 		.procname	= "use_tempaddr",
6833 		.data		= &ipv6_devconf.use_tempaddr,
6834 		.maxlen		= sizeof(int),
6835 		.mode		= 0644,
6836 		.proc_handler	= proc_dointvec,
6837 	},
6838 	{
6839 		.procname	= "temp_valid_lft",
6840 		.data		= &ipv6_devconf.temp_valid_lft,
6841 		.maxlen		= sizeof(int),
6842 		.mode		= 0644,
6843 		.proc_handler	= proc_dointvec,
6844 	},
6845 	{
6846 		.procname	= "temp_prefered_lft",
6847 		.data		= &ipv6_devconf.temp_prefered_lft,
6848 		.maxlen		= sizeof(int),
6849 		.mode		= 0644,
6850 		.proc_handler	= proc_dointvec,
6851 	},
6852 	{
6853 		.procname       = "regen_min_advance",
6854 		.data           = &ipv6_devconf.regen_min_advance,
6855 		.maxlen         = sizeof(int),
6856 		.mode           = 0644,
6857 		.proc_handler   = proc_dointvec,
6858 	},
6859 	{
6860 		.procname	= "regen_max_retry",
6861 		.data		= &ipv6_devconf.regen_max_retry,
6862 		.maxlen		= sizeof(int),
6863 		.mode		= 0644,
6864 		.proc_handler	= proc_dointvec,
6865 	},
6866 	{
6867 		.procname	= "max_desync_factor",
6868 		.data		= &ipv6_devconf.max_desync_factor,
6869 		.maxlen		= sizeof(int),
6870 		.mode		= 0644,
6871 		.proc_handler	= proc_dointvec,
6872 	},
6873 	{
6874 		.procname	= "max_addresses",
6875 		.data		= &ipv6_devconf.max_addresses,
6876 		.maxlen		= sizeof(int),
6877 		.mode		= 0644,
6878 		.proc_handler	= proc_dointvec,
6879 	},
6880 	{
6881 		.procname	= "accept_ra_defrtr",
6882 		.data		= &ipv6_devconf.accept_ra_defrtr,
6883 		.maxlen		= sizeof(int),
6884 		.mode		= 0644,
6885 		.proc_handler	= proc_dointvec,
6886 	},
6887 	{
6888 		.procname	= "ra_defrtr_metric",
6889 		.data		= &ipv6_devconf.ra_defrtr_metric,
6890 		.maxlen		= sizeof(u32),
6891 		.mode		= 0644,
6892 		.proc_handler	= proc_douintvec_minmax,
6893 		.extra1		= (void *)SYSCTL_ONE,
6894 	},
6895 	{
6896 		.procname	= "accept_ra_min_hop_limit",
6897 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6898 		.maxlen		= sizeof(int),
6899 		.mode		= 0644,
6900 		.proc_handler	= proc_dointvec,
6901 	},
6902 	{
6903 		.procname	= "accept_ra_min_lft",
6904 		.data		= &ipv6_devconf.accept_ra_min_lft,
6905 		.maxlen		= sizeof(int),
6906 		.mode		= 0644,
6907 		.proc_handler	= proc_dointvec,
6908 	},
6909 	{
6910 		.procname	= "accept_ra_pinfo",
6911 		.data		= &ipv6_devconf.accept_ra_pinfo,
6912 		.maxlen		= sizeof(int),
6913 		.mode		= 0644,
6914 		.proc_handler	= proc_dointvec,
6915 	},
6916 	{
6917 		.procname	= "ra_honor_pio_life",
6918 		.data		= &ipv6_devconf.ra_honor_pio_life,
6919 		.maxlen		= sizeof(u8),
6920 		.mode		= 0644,
6921 		.proc_handler	= proc_dou8vec_minmax,
6922 		.extra1		= SYSCTL_ZERO,
6923 		.extra2		= SYSCTL_ONE,
6924 	},
6925 #ifdef CONFIG_IPV6_ROUTER_PREF
6926 	{
6927 		.procname	= "accept_ra_rtr_pref",
6928 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6929 		.maxlen		= sizeof(int),
6930 		.mode		= 0644,
6931 		.proc_handler	= proc_dointvec,
6932 	},
6933 	{
6934 		.procname	= "router_probe_interval",
6935 		.data		= &ipv6_devconf.rtr_probe_interval,
6936 		.maxlen		= sizeof(int),
6937 		.mode		= 0644,
6938 		.proc_handler	= proc_dointvec_jiffies,
6939 	},
6940 #ifdef CONFIG_IPV6_ROUTE_INFO
6941 	{
6942 		.procname	= "accept_ra_rt_info_min_plen",
6943 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6944 		.maxlen		= sizeof(int),
6945 		.mode		= 0644,
6946 		.proc_handler	= proc_dointvec,
6947 	},
6948 	{
6949 		.procname	= "accept_ra_rt_info_max_plen",
6950 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6951 		.maxlen		= sizeof(int),
6952 		.mode		= 0644,
6953 		.proc_handler	= proc_dointvec,
6954 	},
6955 #endif
6956 #endif
6957 	{
6958 		.procname	= "proxy_ndp",
6959 		.data		= &ipv6_devconf.proxy_ndp,
6960 		.maxlen		= sizeof(int),
6961 		.mode		= 0644,
6962 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6963 	},
6964 	{
6965 		.procname	= "accept_source_route",
6966 		.data		= &ipv6_devconf.accept_source_route,
6967 		.maxlen		= sizeof(int),
6968 		.mode		= 0644,
6969 		.proc_handler	= proc_dointvec,
6970 	},
6971 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
6972 	{
6973 		.procname	= "optimistic_dad",
6974 		.data		= &ipv6_devconf.optimistic_dad,
6975 		.maxlen		= sizeof(int),
6976 		.mode		= 0644,
6977 		.proc_handler   = proc_dointvec,
6978 	},
6979 	{
6980 		.procname	= "use_optimistic",
6981 		.data		= &ipv6_devconf.use_optimistic,
6982 		.maxlen		= sizeof(int),
6983 		.mode		= 0644,
6984 		.proc_handler	= proc_dointvec,
6985 	},
6986 #endif
6987 #ifdef CONFIG_IPV6_MROUTE
6988 	{
6989 		.procname	= "mc_forwarding",
6990 		.data		= &ipv6_devconf.mc_forwarding,
6991 		.maxlen		= sizeof(int),
6992 		.mode		= 0444,
6993 		.proc_handler	= proc_dointvec,
6994 	},
6995 #endif
6996 	{
6997 		.procname	= "disable_ipv6",
6998 		.data		= &ipv6_devconf.disable_ipv6,
6999 		.maxlen		= sizeof(int),
7000 		.mode		= 0644,
7001 		.proc_handler	= addrconf_sysctl_disable,
7002 	},
7003 	{
7004 		.procname	= "accept_dad",
7005 		.data		= &ipv6_devconf.accept_dad,
7006 		.maxlen		= sizeof(int),
7007 		.mode		= 0644,
7008 		.proc_handler	= proc_dointvec,
7009 	},
7010 	{
7011 		.procname	= "force_tllao",
7012 		.data		= &ipv6_devconf.force_tllao,
7013 		.maxlen		= sizeof(int),
7014 		.mode		= 0644,
7015 		.proc_handler	= proc_dointvec
7016 	},
7017 	{
7018 		.procname	= "ndisc_notify",
7019 		.data		= &ipv6_devconf.ndisc_notify,
7020 		.maxlen		= sizeof(int),
7021 		.mode		= 0644,
7022 		.proc_handler	= proc_dointvec
7023 	},
7024 	{
7025 		.procname	= "suppress_frag_ndisc",
7026 		.data		= &ipv6_devconf.suppress_frag_ndisc,
7027 		.maxlen		= sizeof(int),
7028 		.mode		= 0644,
7029 		.proc_handler	= proc_dointvec
7030 	},
7031 	{
7032 		.procname	= "accept_ra_from_local",
7033 		.data		= &ipv6_devconf.accept_ra_from_local,
7034 		.maxlen		= sizeof(int),
7035 		.mode		= 0644,
7036 		.proc_handler	= proc_dointvec,
7037 	},
7038 	{
7039 		.procname	= "accept_ra_mtu",
7040 		.data		= &ipv6_devconf.accept_ra_mtu,
7041 		.maxlen		= sizeof(int),
7042 		.mode		= 0644,
7043 		.proc_handler	= proc_dointvec,
7044 	},
7045 	{
7046 		.procname	= "stable_secret",
7047 		.data		= &ipv6_devconf.stable_secret,
7048 		.maxlen		= IPV6_MAX_STRLEN,
7049 		.mode		= 0600,
7050 		.proc_handler	= addrconf_sysctl_stable_secret,
7051 	},
7052 	{
7053 		.procname	= "use_oif_addrs_only",
7054 		.data		= &ipv6_devconf.use_oif_addrs_only,
7055 		.maxlen		= sizeof(int),
7056 		.mode		= 0644,
7057 		.proc_handler	= proc_dointvec,
7058 	},
7059 	{
7060 		.procname	= "ignore_routes_with_linkdown",
7061 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
7062 		.maxlen		= sizeof(int),
7063 		.mode		= 0644,
7064 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
7065 	},
7066 	{
7067 		.procname	= "drop_unicast_in_l2_multicast",
7068 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
7069 		.maxlen		= sizeof(int),
7070 		.mode		= 0644,
7071 		.proc_handler	= proc_dointvec,
7072 	},
7073 	{
7074 		.procname	= "drop_unsolicited_na",
7075 		.data		= &ipv6_devconf.drop_unsolicited_na,
7076 		.maxlen		= sizeof(int),
7077 		.mode		= 0644,
7078 		.proc_handler	= proc_dointvec,
7079 	},
7080 	{
7081 		.procname	= "keep_addr_on_down",
7082 		.data		= &ipv6_devconf.keep_addr_on_down,
7083 		.maxlen		= sizeof(int),
7084 		.mode		= 0644,
7085 		.proc_handler	= proc_dointvec,
7086 
7087 	},
7088 	{
7089 		.procname	= "seg6_enabled",
7090 		.data		= &ipv6_devconf.seg6_enabled,
7091 		.maxlen		= sizeof(int),
7092 		.mode		= 0644,
7093 		.proc_handler	= proc_dointvec,
7094 	},
7095 #ifdef CONFIG_IPV6_SEG6_HMAC
7096 	{
7097 		.procname	= "seg6_require_hmac",
7098 		.data		= &ipv6_devconf.seg6_require_hmac,
7099 		.maxlen		= sizeof(int),
7100 		.mode		= 0644,
7101 		.proc_handler	= proc_dointvec,
7102 	},
7103 #endif
7104 	{
7105 		.procname       = "enhanced_dad",
7106 		.data           = &ipv6_devconf.enhanced_dad,
7107 		.maxlen         = sizeof(int),
7108 		.mode           = 0644,
7109 		.proc_handler   = proc_dointvec,
7110 	},
7111 	{
7112 		.procname	= "addr_gen_mode",
7113 		.data		= &ipv6_devconf.addr_gen_mode,
7114 		.maxlen		= sizeof(int),
7115 		.mode		= 0644,
7116 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
7117 	},
7118 	{
7119 		.procname       = "disable_policy",
7120 		.data           = &ipv6_devconf.disable_policy,
7121 		.maxlen         = sizeof(int),
7122 		.mode           = 0644,
7123 		.proc_handler   = addrconf_sysctl_disable_policy,
7124 	},
7125 	{
7126 		.procname	= "ndisc_tclass",
7127 		.data		= &ipv6_devconf.ndisc_tclass,
7128 		.maxlen		= sizeof(int),
7129 		.mode		= 0644,
7130 		.proc_handler	= proc_dointvec_minmax,
7131 		.extra1		= (void *)SYSCTL_ZERO,
7132 		.extra2		= (void *)&two_five_five,
7133 	},
7134 	{
7135 		.procname	= "rpl_seg_enabled",
7136 		.data		= &ipv6_devconf.rpl_seg_enabled,
7137 		.maxlen		= sizeof(int),
7138 		.mode		= 0644,
7139 		.proc_handler	= proc_dointvec,
7140 	},
7141 	{
7142 		.procname	= "ioam6_enabled",
7143 		.data		= &ipv6_devconf.ioam6_enabled,
7144 		.maxlen		= sizeof(u8),
7145 		.mode		= 0644,
7146 		.proc_handler	= proc_dou8vec_minmax,
7147 		.extra1		= (void *)SYSCTL_ZERO,
7148 		.extra2		= (void *)SYSCTL_ONE,
7149 	},
7150 	{
7151 		.procname	= "ioam6_id",
7152 		.data		= &ipv6_devconf.ioam6_id,
7153 		.maxlen		= sizeof(u32),
7154 		.mode		= 0644,
7155 		.proc_handler	= proc_douintvec_minmax,
7156 		.extra1		= (void *)SYSCTL_ZERO,
7157 		.extra2		= (void *)&ioam6_if_id_max,
7158 	},
7159 	{
7160 		.procname	= "ioam6_id_wide",
7161 		.data		= &ipv6_devconf.ioam6_id_wide,
7162 		.maxlen		= sizeof(u32),
7163 		.mode		= 0644,
7164 		.proc_handler	= proc_douintvec,
7165 	},
7166 	{
7167 		.procname	= "ndisc_evict_nocarrier",
7168 		.data		= &ipv6_devconf.ndisc_evict_nocarrier,
7169 		.maxlen		= sizeof(u8),
7170 		.mode		= 0644,
7171 		.proc_handler	= proc_dou8vec_minmax,
7172 		.extra1		= (void *)SYSCTL_ZERO,
7173 		.extra2		= (void *)SYSCTL_ONE,
7174 	},
7175 	{
7176 		.procname	= "accept_untracked_na",
7177 		.data		= &ipv6_devconf.accept_untracked_na,
7178 		.maxlen		= sizeof(int),
7179 		.mode		= 0644,
7180 		.proc_handler	= proc_dointvec_minmax,
7181 		.extra1		= SYSCTL_ZERO,
7182 		.extra2		= SYSCTL_TWO,
7183 	},
7184 	{
7185 		/* sentinel */
7186 	}
7187 };
7188 
7189 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
7190 		struct inet6_dev *idev, struct ipv6_devconf *p)
7191 {
7192 	int i, ifindex;
7193 	struct ctl_table *table;
7194 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
7195 
7196 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL_ACCOUNT);
7197 	if (!table)
7198 		goto out;
7199 
7200 	for (i = 0; table[i].data; i++) {
7201 		table[i].data += (char *)p - (char *)&ipv6_devconf;
7202 		/* If one of these is already set, then it is not safe to
7203 		 * overwrite either of them: this makes proc_dointvec_minmax
7204 		 * usable.
7205 		 */
7206 		if (!table[i].extra1 && !table[i].extra2) {
7207 			table[i].extra1 = idev; /* embedded; no ref */
7208 			table[i].extra2 = net;
7209 		}
7210 	}
7211 
7212 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
7213 
7214 	p->sysctl_header = register_net_sysctl_sz(net, path, table,
7215 						  ARRAY_SIZE(addrconf_sysctl));
7216 	if (!p->sysctl_header)
7217 		goto free;
7218 
7219 	if (!strcmp(dev_name, "all"))
7220 		ifindex = NETCONFA_IFINDEX_ALL;
7221 	else if (!strcmp(dev_name, "default"))
7222 		ifindex = NETCONFA_IFINDEX_DEFAULT;
7223 	else
7224 		ifindex = idev->dev->ifindex;
7225 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
7226 				     ifindex, p);
7227 	return 0;
7228 
7229 free:
7230 	kfree(table);
7231 out:
7232 	return -ENOBUFS;
7233 }
7234 
7235 static void __addrconf_sysctl_unregister(struct net *net,
7236 					 struct ipv6_devconf *p, int ifindex)
7237 {
7238 	struct ctl_table *table;
7239 
7240 	if (!p->sysctl_header)
7241 		return;
7242 
7243 	table = p->sysctl_header->ctl_table_arg;
7244 	unregister_net_sysctl_table(p->sysctl_header);
7245 	p->sysctl_header = NULL;
7246 	kfree(table);
7247 
7248 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
7249 }
7250 
7251 static int addrconf_sysctl_register(struct inet6_dev *idev)
7252 {
7253 	int err;
7254 
7255 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
7256 		return -EINVAL;
7257 
7258 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
7259 				    &ndisc_ifinfo_sysctl_change);
7260 	if (err)
7261 		return err;
7262 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
7263 					 idev, &idev->cnf);
7264 	if (err)
7265 		neigh_sysctl_unregister(idev->nd_parms);
7266 
7267 	return err;
7268 }
7269 
7270 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
7271 {
7272 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
7273 				     idev->dev->ifindex);
7274 	neigh_sysctl_unregister(idev->nd_parms);
7275 }
7276 
7277 
7278 #endif
7279 
7280 static int __net_init addrconf_init_net(struct net *net)
7281 {
7282 	int err = -ENOMEM;
7283 	struct ipv6_devconf *all, *dflt;
7284 
7285 	spin_lock_init(&net->ipv6.addrconf_hash_lock);
7286 	INIT_DEFERRABLE_WORK(&net->ipv6.addr_chk_work, addrconf_verify_work);
7287 	net->ipv6.inet6_addr_lst = kcalloc(IN6_ADDR_HSIZE,
7288 					   sizeof(struct hlist_head),
7289 					   GFP_KERNEL);
7290 	if (!net->ipv6.inet6_addr_lst)
7291 		goto err_alloc_addr;
7292 
7293 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
7294 	if (!all)
7295 		goto err_alloc_all;
7296 
7297 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
7298 	if (!dflt)
7299 		goto err_alloc_dflt;
7300 
7301 	if (!net_eq(net, &init_net)) {
7302 		switch (net_inherit_devconf()) {
7303 		case 1:  /* copy from init_net */
7304 			memcpy(all, init_net.ipv6.devconf_all,
7305 			       sizeof(ipv6_devconf));
7306 			memcpy(dflt, init_net.ipv6.devconf_dflt,
7307 			       sizeof(ipv6_devconf_dflt));
7308 			break;
7309 		case 3: /* copy from the current netns */
7310 			memcpy(all, current->nsproxy->net_ns->ipv6.devconf_all,
7311 			       sizeof(ipv6_devconf));
7312 			memcpy(dflt,
7313 			       current->nsproxy->net_ns->ipv6.devconf_dflt,
7314 			       sizeof(ipv6_devconf_dflt));
7315 			break;
7316 		case 0:
7317 		case 2:
7318 			/* use compiled values */
7319 			break;
7320 		}
7321 	}
7322 
7323 	/* these will be inherited by all namespaces */
7324 	dflt->autoconf = ipv6_defaults.autoconf;
7325 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
7326 
7327 	dflt->stable_secret.initialized = false;
7328 	all->stable_secret.initialized = false;
7329 
7330 	net->ipv6.devconf_all = all;
7331 	net->ipv6.devconf_dflt = dflt;
7332 
7333 #ifdef CONFIG_SYSCTL
7334 	err = __addrconf_sysctl_register(net, "all", NULL, all);
7335 	if (err < 0)
7336 		goto err_reg_all;
7337 
7338 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
7339 	if (err < 0)
7340 		goto err_reg_dflt;
7341 #endif
7342 	return 0;
7343 
7344 #ifdef CONFIG_SYSCTL
7345 err_reg_dflt:
7346 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
7347 err_reg_all:
7348 	kfree(dflt);
7349 	net->ipv6.devconf_dflt = NULL;
7350 #endif
7351 err_alloc_dflt:
7352 	kfree(all);
7353 	net->ipv6.devconf_all = NULL;
7354 err_alloc_all:
7355 	kfree(net->ipv6.inet6_addr_lst);
7356 err_alloc_addr:
7357 	return err;
7358 }
7359 
7360 static void __net_exit addrconf_exit_net(struct net *net)
7361 {
7362 	int i;
7363 
7364 #ifdef CONFIG_SYSCTL
7365 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
7366 				     NETCONFA_IFINDEX_DEFAULT);
7367 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
7368 				     NETCONFA_IFINDEX_ALL);
7369 #endif
7370 	kfree(net->ipv6.devconf_dflt);
7371 	net->ipv6.devconf_dflt = NULL;
7372 	kfree(net->ipv6.devconf_all);
7373 	net->ipv6.devconf_all = NULL;
7374 
7375 	cancel_delayed_work_sync(&net->ipv6.addr_chk_work);
7376 	/*
7377 	 *	Check hash table, then free it.
7378 	 */
7379 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7380 		WARN_ON_ONCE(!hlist_empty(&net->ipv6.inet6_addr_lst[i]));
7381 
7382 	kfree(net->ipv6.inet6_addr_lst);
7383 	net->ipv6.inet6_addr_lst = NULL;
7384 }
7385 
7386 static struct pernet_operations addrconf_ops = {
7387 	.init = addrconf_init_net,
7388 	.exit = addrconf_exit_net,
7389 };
7390 
7391 static struct rtnl_af_ops inet6_ops __read_mostly = {
7392 	.family		  = AF_INET6,
7393 	.fill_link_af	  = inet6_fill_link_af,
7394 	.get_link_af_size = inet6_get_link_af_size,
7395 	.validate_link_af = inet6_validate_link_af,
7396 	.set_link_af	  = inet6_set_link_af,
7397 };
7398 
7399 /*
7400  *	Init / cleanup code
7401  */
7402 
7403 int __init addrconf_init(void)
7404 {
7405 	struct inet6_dev *idev;
7406 	int err;
7407 
7408 	err = ipv6_addr_label_init();
7409 	if (err < 0) {
7410 		pr_crit("%s: cannot initialize default policy table: %d\n",
7411 			__func__, err);
7412 		goto out;
7413 	}
7414 
7415 	err = register_pernet_subsys(&addrconf_ops);
7416 	if (err < 0)
7417 		goto out_addrlabel;
7418 
7419 	/* All works using addrconf_wq need to lock rtnl. */
7420 	addrconf_wq = create_singlethread_workqueue("ipv6_addrconf");
7421 	if (!addrconf_wq) {
7422 		err = -ENOMEM;
7423 		goto out_nowq;
7424 	}
7425 
7426 	rtnl_lock();
7427 	idev = ipv6_add_dev(blackhole_netdev);
7428 	rtnl_unlock();
7429 	if (IS_ERR(idev)) {
7430 		err = PTR_ERR(idev);
7431 		goto errlo;
7432 	}
7433 
7434 	ip6_route_init_special_entries();
7435 
7436 	register_netdevice_notifier(&ipv6_dev_notf);
7437 
7438 	addrconf_verify(&init_net);
7439 
7440 	rtnl_af_register(&inet6_ops);
7441 
7442 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETLINK,
7443 				   NULL, inet6_dump_ifinfo, RTNL_FLAG_DUMP_UNLOCKED);
7444 	if (err < 0)
7445 		goto errout;
7446 
7447 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWADDR,
7448 				   inet6_rtm_newaddr, NULL, 0);
7449 	if (err < 0)
7450 		goto errout;
7451 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELADDR,
7452 				   inet6_rtm_deladdr, NULL, 0);
7453 	if (err < 0)
7454 		goto errout;
7455 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDR,
7456 				   inet6_rtm_getaddr, inet6_dump_ifaddr,
7457 				   RTNL_FLAG_DOIT_UNLOCKED |
7458 				   RTNL_FLAG_DUMP_UNLOCKED);
7459 	if (err < 0)
7460 		goto errout;
7461 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETMULTICAST,
7462 				   NULL, inet6_dump_ifmcaddr,
7463 				   RTNL_FLAG_DUMP_UNLOCKED);
7464 	if (err < 0)
7465 		goto errout;
7466 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETANYCAST,
7467 				   NULL, inet6_dump_ifacaddr,
7468 				   RTNL_FLAG_DUMP_UNLOCKED);
7469 	if (err < 0)
7470 		goto errout;
7471 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETNETCONF,
7472 				   inet6_netconf_get_devconf,
7473 				   inet6_netconf_dump_devconf,
7474 				   RTNL_FLAG_DOIT_UNLOCKED |
7475 				   RTNL_FLAG_DUMP_UNLOCKED);
7476 	if (err < 0)
7477 		goto errout;
7478 	err = ipv6_addr_label_rtnl_register();
7479 	if (err < 0)
7480 		goto errout;
7481 
7482 	return 0;
7483 errout:
7484 	rtnl_unregister_all(PF_INET6);
7485 	rtnl_af_unregister(&inet6_ops);
7486 	unregister_netdevice_notifier(&ipv6_dev_notf);
7487 errlo:
7488 	destroy_workqueue(addrconf_wq);
7489 out_nowq:
7490 	unregister_pernet_subsys(&addrconf_ops);
7491 out_addrlabel:
7492 	ipv6_addr_label_cleanup();
7493 out:
7494 	return err;
7495 }
7496 
7497 void addrconf_cleanup(void)
7498 {
7499 	struct net_device *dev;
7500 
7501 	unregister_netdevice_notifier(&ipv6_dev_notf);
7502 	unregister_pernet_subsys(&addrconf_ops);
7503 	ipv6_addr_label_cleanup();
7504 
7505 	rtnl_af_unregister(&inet6_ops);
7506 
7507 	rtnl_lock();
7508 
7509 	/* clean dev list */
7510 	for_each_netdev(&init_net, dev) {
7511 		if (__in6_dev_get(dev) == NULL)
7512 			continue;
7513 		addrconf_ifdown(dev, true);
7514 	}
7515 	addrconf_ifdown(init_net.loopback_dev, true);
7516 
7517 	rtnl_unlock();
7518 
7519 	destroy_workqueue(addrconf_wq);
7520 }
7521