xref: /openbmc/linux/net/ipv6/addrconf.c (revision 2985bed6)
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 
93 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
94 
95 #define IPV6_MAX_STRLEN \
96 	sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")
97 
98 static inline u32 cstamp_delta(unsigned long cstamp)
99 {
100 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
101 }
102 
103 static inline s32 rfc3315_s14_backoff_init(s32 irt)
104 {
105 	/* multiply 'initial retransmission time' by 0.9 .. 1.1 */
106 	u64 tmp = (900000 + prandom_u32() % 200001) * (u64)irt;
107 	do_div(tmp, 1000000);
108 	return (s32)tmp;
109 }
110 
111 static inline s32 rfc3315_s14_backoff_update(s32 rt, s32 mrt)
112 {
113 	/* multiply 'retransmission timeout' by 1.9 .. 2.1 */
114 	u64 tmp = (1900000 + prandom_u32() % 200001) * (u64)rt;
115 	do_div(tmp, 1000000);
116 	if ((s32)tmp > mrt) {
117 		/* multiply 'maximum retransmission time' by 0.9 .. 1.1 */
118 		tmp = (900000 + prandom_u32() % 200001) * (u64)mrt;
119 		do_div(tmp, 1000000);
120 	}
121 	return (s32)tmp;
122 }
123 
124 #ifdef CONFIG_SYSCTL
125 static int addrconf_sysctl_register(struct inet6_dev *idev);
126 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
127 #else
128 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
129 {
130 	return 0;
131 }
132 
133 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
134 {
135 }
136 #endif
137 
138 static void ipv6_regen_rndid(struct inet6_dev *idev);
139 static void ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
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  *	Configured unicast address hash table
151  */
152 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
153 static DEFINE_SPINLOCK(addrconf_hash_lock);
154 
155 static void addrconf_verify(void);
156 static void addrconf_verify_rtnl(void);
157 static void addrconf_verify_work(struct work_struct *);
158 
159 static struct workqueue_struct *addrconf_wq;
160 static DECLARE_DELAYED_WORK(addr_chk_work, addrconf_verify_work);
161 
162 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
163 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
164 
165 static void addrconf_type_change(struct net_device *dev,
166 				 unsigned long event);
167 static int addrconf_ifdown(struct net_device *dev, int how);
168 
169 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
170 						  int plen,
171 						  const struct net_device *dev,
172 						  u32 flags, u32 noflags,
173 						  bool no_gw);
174 
175 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
176 static void addrconf_dad_work(struct work_struct *w);
177 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
178 				   bool send_na);
179 static void addrconf_dad_run(struct inet6_dev *idev, bool restart);
180 static void addrconf_rs_timer(struct timer_list *t);
181 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
182 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
183 
184 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
185 				struct prefix_info *pinfo);
186 
187 static struct ipv6_devconf ipv6_devconf __read_mostly = {
188 	.forwarding		= 0,
189 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
190 	.mtu6			= IPV6_MIN_MTU,
191 	.accept_ra		= 1,
192 	.accept_redirects	= 1,
193 	.autoconf		= 1,
194 	.force_mld_version	= 0,
195 	.mldv1_unsolicited_report_interval = 10 * HZ,
196 	.mldv2_unsolicited_report_interval = HZ,
197 	.dad_transmits		= 1,
198 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
199 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
200 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
201 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
202 	.use_tempaddr		= 0,
203 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
204 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
205 	.regen_max_retry	= REGEN_MAX_RETRY,
206 	.max_desync_factor	= MAX_DESYNC_FACTOR,
207 	.max_addresses		= IPV6_MAX_ADDRESSES,
208 	.accept_ra_defrtr	= 1,
209 	.accept_ra_from_local	= 0,
210 	.accept_ra_min_hop_limit= 1,
211 	.accept_ra_pinfo	= 1,
212 #ifdef CONFIG_IPV6_ROUTER_PREF
213 	.accept_ra_rtr_pref	= 1,
214 	.rtr_probe_interval	= 60 * HZ,
215 #ifdef CONFIG_IPV6_ROUTE_INFO
216 	.accept_ra_rt_info_min_plen = 0,
217 	.accept_ra_rt_info_max_plen = 0,
218 #endif
219 #endif
220 	.proxy_ndp		= 0,
221 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
222 	.disable_ipv6		= 0,
223 	.accept_dad		= 0,
224 	.suppress_frag_ndisc	= 1,
225 	.accept_ra_mtu		= 1,
226 	.stable_secret		= {
227 		.initialized = false,
228 	},
229 	.use_oif_addrs_only	= 0,
230 	.ignore_routes_with_linkdown = 0,
231 	.keep_addr_on_down	= 0,
232 	.seg6_enabled		= 0,
233 #ifdef CONFIG_IPV6_SEG6_HMAC
234 	.seg6_require_hmac	= 0,
235 #endif
236 	.enhanced_dad           = 1,
237 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
238 	.disable_policy		= 0,
239 };
240 
241 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
242 	.forwarding		= 0,
243 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
244 	.mtu6			= IPV6_MIN_MTU,
245 	.accept_ra		= 1,
246 	.accept_redirects	= 1,
247 	.autoconf		= 1,
248 	.force_mld_version	= 0,
249 	.mldv1_unsolicited_report_interval = 10 * HZ,
250 	.mldv2_unsolicited_report_interval = HZ,
251 	.dad_transmits		= 1,
252 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
253 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
254 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
255 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
256 	.use_tempaddr		= 0,
257 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
258 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
259 	.regen_max_retry	= REGEN_MAX_RETRY,
260 	.max_desync_factor	= MAX_DESYNC_FACTOR,
261 	.max_addresses		= IPV6_MAX_ADDRESSES,
262 	.accept_ra_defrtr	= 1,
263 	.accept_ra_from_local	= 0,
264 	.accept_ra_min_hop_limit= 1,
265 	.accept_ra_pinfo	= 1,
266 #ifdef CONFIG_IPV6_ROUTER_PREF
267 	.accept_ra_rtr_pref	= 1,
268 	.rtr_probe_interval	= 60 * HZ,
269 #ifdef CONFIG_IPV6_ROUTE_INFO
270 	.accept_ra_rt_info_min_plen = 0,
271 	.accept_ra_rt_info_max_plen = 0,
272 #endif
273 #endif
274 	.proxy_ndp		= 0,
275 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
276 	.disable_ipv6		= 0,
277 	.accept_dad		= 1,
278 	.suppress_frag_ndisc	= 1,
279 	.accept_ra_mtu		= 1,
280 	.stable_secret		= {
281 		.initialized = false,
282 	},
283 	.use_oif_addrs_only	= 0,
284 	.ignore_routes_with_linkdown = 0,
285 	.keep_addr_on_down	= 0,
286 	.seg6_enabled		= 0,
287 #ifdef CONFIG_IPV6_SEG6_HMAC
288 	.seg6_require_hmac	= 0,
289 #endif
290 	.enhanced_dad           = 1,
291 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
292 	.disable_policy		= 0,
293 };
294 
295 /* Check if link is ready: is it up and is a valid qdisc available */
296 static inline bool addrconf_link_ready(const struct net_device *dev)
297 {
298 	return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
299 }
300 
301 static void addrconf_del_rs_timer(struct inet6_dev *idev)
302 {
303 	if (del_timer(&idev->rs_timer))
304 		__in6_dev_put(idev);
305 }
306 
307 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
308 {
309 	if (cancel_delayed_work(&ifp->dad_work))
310 		__in6_ifa_put(ifp);
311 }
312 
313 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
314 				  unsigned long when)
315 {
316 	if (!timer_pending(&idev->rs_timer))
317 		in6_dev_hold(idev);
318 	mod_timer(&idev->rs_timer, jiffies + when);
319 }
320 
321 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
322 				   unsigned long delay)
323 {
324 	in6_ifa_hold(ifp);
325 	if (mod_delayed_work(addrconf_wq, &ifp->dad_work, delay))
326 		in6_ifa_put(ifp);
327 }
328 
329 static int snmp6_alloc_dev(struct inet6_dev *idev)
330 {
331 	int i;
332 
333 	idev->stats.ipv6 = alloc_percpu(struct ipstats_mib);
334 	if (!idev->stats.ipv6)
335 		goto err_ip;
336 
337 	for_each_possible_cpu(i) {
338 		struct ipstats_mib *addrconf_stats;
339 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
340 		u64_stats_init(&addrconf_stats->syncp);
341 	}
342 
343 
344 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
345 					GFP_KERNEL);
346 	if (!idev->stats.icmpv6dev)
347 		goto err_icmp;
348 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
349 					   GFP_KERNEL);
350 	if (!idev->stats.icmpv6msgdev)
351 		goto err_icmpmsg;
352 
353 	return 0;
354 
355 err_icmpmsg:
356 	kfree(idev->stats.icmpv6dev);
357 err_icmp:
358 	free_percpu(idev->stats.ipv6);
359 err_ip:
360 	return -ENOMEM;
361 }
362 
363 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
364 {
365 	struct inet6_dev *ndev;
366 	int err = -ENOMEM;
367 
368 	ASSERT_RTNL();
369 
370 	if (dev->mtu < IPV6_MIN_MTU)
371 		return ERR_PTR(-EINVAL);
372 
373 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
374 	if (!ndev)
375 		return ERR_PTR(err);
376 
377 	rwlock_init(&ndev->lock);
378 	ndev->dev = dev;
379 	INIT_LIST_HEAD(&ndev->addr_list);
380 	timer_setup(&ndev->rs_timer, addrconf_rs_timer, 0);
381 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
382 
383 	if (ndev->cnf.stable_secret.initialized)
384 		ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
385 
386 	ndev->cnf.mtu6 = dev->mtu;
387 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
388 	if (!ndev->nd_parms) {
389 		kfree(ndev);
390 		return ERR_PTR(err);
391 	}
392 	if (ndev->cnf.forwarding)
393 		dev_disable_lro(dev);
394 	/* We refer to the device */
395 	dev_hold(dev);
396 
397 	if (snmp6_alloc_dev(ndev) < 0) {
398 		netdev_dbg(dev, "%s: cannot allocate memory for statistics\n",
399 			   __func__);
400 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
401 		dev_put(dev);
402 		kfree(ndev);
403 		return ERR_PTR(err);
404 	}
405 
406 	if (snmp6_register_dev(ndev) < 0) {
407 		netdev_dbg(dev, "%s: cannot create /proc/net/dev_snmp6/%s\n",
408 			   __func__, dev->name);
409 		goto err_release;
410 	}
411 
412 	/* One reference from device. */
413 	refcount_set(&ndev->refcnt, 1);
414 
415 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
416 		ndev->cnf.accept_dad = -1;
417 
418 #if IS_ENABLED(CONFIG_IPV6_SIT)
419 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
420 		pr_info("%s: Disabled Multicast RS\n", dev->name);
421 		ndev->cnf.rtr_solicits = 0;
422 	}
423 #endif
424 
425 	INIT_LIST_HEAD(&ndev->tempaddr_list);
426 	ndev->desync_factor = U32_MAX;
427 	if ((dev->flags&IFF_LOOPBACK) ||
428 	    dev->type == ARPHRD_TUNNEL ||
429 	    dev->type == ARPHRD_TUNNEL6 ||
430 	    dev->type == ARPHRD_SIT ||
431 	    dev->type == ARPHRD_NONE) {
432 		ndev->cnf.use_tempaddr = -1;
433 	} else
434 		ipv6_regen_rndid(ndev);
435 
436 	ndev->token = in6addr_any;
437 
438 	if (netif_running(dev) && addrconf_link_ready(dev))
439 		ndev->if_flags |= IF_READY;
440 
441 	ipv6_mc_init_dev(ndev);
442 	ndev->tstamp = jiffies;
443 	err = addrconf_sysctl_register(ndev);
444 	if (err) {
445 		ipv6_mc_destroy_dev(ndev);
446 		snmp6_unregister_dev(ndev);
447 		goto err_release;
448 	}
449 	/* protected by rtnl_lock */
450 	rcu_assign_pointer(dev->ip6_ptr, ndev);
451 
452 	/* Join interface-local all-node multicast group */
453 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
454 
455 	/* Join all-node multicast group */
456 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
457 
458 	/* Join all-router multicast group if forwarding is set */
459 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
460 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
461 
462 	return ndev;
463 
464 err_release:
465 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
466 	ndev->dead = 1;
467 	in6_dev_finish_destroy(ndev);
468 	return ERR_PTR(err);
469 }
470 
471 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
472 {
473 	struct inet6_dev *idev;
474 
475 	ASSERT_RTNL();
476 
477 	idev = __in6_dev_get(dev);
478 	if (!idev) {
479 		idev = ipv6_add_dev(dev);
480 		if (IS_ERR(idev))
481 			return idev;
482 	}
483 
484 	if (dev->flags&IFF_UP)
485 		ipv6_mc_up(idev);
486 	return idev;
487 }
488 
489 static int inet6_netconf_msgsize_devconf(int type)
490 {
491 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
492 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
493 	bool all = false;
494 
495 	if (type == NETCONFA_ALL)
496 		all = true;
497 
498 	if (all || type == NETCONFA_FORWARDING)
499 		size += nla_total_size(4);
500 #ifdef CONFIG_IPV6_MROUTE
501 	if (all || type == NETCONFA_MC_FORWARDING)
502 		size += nla_total_size(4);
503 #endif
504 	if (all || type == NETCONFA_PROXY_NEIGH)
505 		size += nla_total_size(4);
506 
507 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
508 		size += nla_total_size(4);
509 
510 	return size;
511 }
512 
513 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
514 				      struct ipv6_devconf *devconf, u32 portid,
515 				      u32 seq, int event, unsigned int flags,
516 				      int type)
517 {
518 	struct nlmsghdr  *nlh;
519 	struct netconfmsg *ncm;
520 	bool all = false;
521 
522 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
523 			flags);
524 	if (!nlh)
525 		return -EMSGSIZE;
526 
527 	if (type == NETCONFA_ALL)
528 		all = true;
529 
530 	ncm = nlmsg_data(nlh);
531 	ncm->ncm_family = AF_INET6;
532 
533 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
534 		goto nla_put_failure;
535 
536 	if (!devconf)
537 		goto out;
538 
539 	if ((all || type == NETCONFA_FORWARDING) &&
540 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
541 		goto nla_put_failure;
542 #ifdef CONFIG_IPV6_MROUTE
543 	if ((all || type == NETCONFA_MC_FORWARDING) &&
544 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
545 			devconf->mc_forwarding) < 0)
546 		goto nla_put_failure;
547 #endif
548 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
549 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
550 		goto nla_put_failure;
551 
552 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
553 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
554 			devconf->ignore_routes_with_linkdown) < 0)
555 		goto nla_put_failure;
556 
557 out:
558 	nlmsg_end(skb, nlh);
559 	return 0;
560 
561 nla_put_failure:
562 	nlmsg_cancel(skb, nlh);
563 	return -EMSGSIZE;
564 }
565 
566 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
567 				  int ifindex, struct ipv6_devconf *devconf)
568 {
569 	struct sk_buff *skb;
570 	int err = -ENOBUFS;
571 
572 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
573 	if (!skb)
574 		goto errout;
575 
576 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
577 					 event, 0, type);
578 	if (err < 0) {
579 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
580 		WARN_ON(err == -EMSGSIZE);
581 		kfree_skb(skb);
582 		goto errout;
583 	}
584 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
585 	return;
586 errout:
587 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
588 }
589 
590 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
591 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
592 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
593 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
594 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
595 };
596 
597 static int inet6_netconf_valid_get_req(struct sk_buff *skb,
598 				       const struct nlmsghdr *nlh,
599 				       struct nlattr **tb,
600 				       struct netlink_ext_ack *extack)
601 {
602 	int i, err;
603 
604 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(struct netconfmsg))) {
605 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf get request");
606 		return -EINVAL;
607 	}
608 
609 	if (!netlink_strict_get_check(skb))
610 		return nlmsg_parse_deprecated(nlh, sizeof(struct netconfmsg),
611 					      tb, NETCONFA_MAX,
612 					      devconf_ipv6_policy, extack);
613 
614 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct netconfmsg),
615 					    tb, NETCONFA_MAX,
616 					    devconf_ipv6_policy, extack);
617 	if (err)
618 		return err;
619 
620 	for (i = 0; i <= NETCONFA_MAX; i++) {
621 		if (!tb[i])
622 			continue;
623 
624 		switch (i) {
625 		case NETCONFA_IFINDEX:
626 			break;
627 		default:
628 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in netconf get request");
629 			return -EINVAL;
630 		}
631 	}
632 
633 	return 0;
634 }
635 
636 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
637 				     struct nlmsghdr *nlh,
638 				     struct netlink_ext_ack *extack)
639 {
640 	struct net *net = sock_net(in_skb->sk);
641 	struct nlattr *tb[NETCONFA_MAX+1];
642 	struct inet6_dev *in6_dev = NULL;
643 	struct net_device *dev = NULL;
644 	struct sk_buff *skb;
645 	struct ipv6_devconf *devconf;
646 	int ifindex;
647 	int err;
648 
649 	err = inet6_netconf_valid_get_req(in_skb, nlh, tb, extack);
650 	if (err < 0)
651 		return err;
652 
653 	if (!tb[NETCONFA_IFINDEX])
654 		return -EINVAL;
655 
656 	err = -EINVAL;
657 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
658 	switch (ifindex) {
659 	case NETCONFA_IFINDEX_ALL:
660 		devconf = net->ipv6.devconf_all;
661 		break;
662 	case NETCONFA_IFINDEX_DEFAULT:
663 		devconf = net->ipv6.devconf_dflt;
664 		break;
665 	default:
666 		dev = dev_get_by_index(net, ifindex);
667 		if (!dev)
668 			return -EINVAL;
669 		in6_dev = in6_dev_get(dev);
670 		if (!in6_dev)
671 			goto errout;
672 		devconf = &in6_dev->cnf;
673 		break;
674 	}
675 
676 	err = -ENOBUFS;
677 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
678 	if (!skb)
679 		goto errout;
680 
681 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
682 					 NETLINK_CB(in_skb).portid,
683 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
684 					 NETCONFA_ALL);
685 	if (err < 0) {
686 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
687 		WARN_ON(err == -EMSGSIZE);
688 		kfree_skb(skb);
689 		goto errout;
690 	}
691 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
692 errout:
693 	if (in6_dev)
694 		in6_dev_put(in6_dev);
695 	if (dev)
696 		dev_put(dev);
697 	return err;
698 }
699 
700 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
701 				      struct netlink_callback *cb)
702 {
703 	const struct nlmsghdr *nlh = cb->nlh;
704 	struct net *net = sock_net(skb->sk);
705 	int h, s_h;
706 	int idx, s_idx;
707 	struct net_device *dev;
708 	struct inet6_dev *idev;
709 	struct hlist_head *head;
710 
711 	if (cb->strict_check) {
712 		struct netlink_ext_ack *extack = cb->extack;
713 		struct netconfmsg *ncm;
714 
715 		if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) {
716 			NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf dump request");
717 			return -EINVAL;
718 		}
719 
720 		if (nlmsg_attrlen(nlh, sizeof(*ncm))) {
721 			NL_SET_ERR_MSG_MOD(extack, "Invalid data after header in netconf dump request");
722 			return -EINVAL;
723 		}
724 	}
725 
726 	s_h = cb->args[0];
727 	s_idx = idx = cb->args[1];
728 
729 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
730 		idx = 0;
731 		head = &net->dev_index_head[h];
732 		rcu_read_lock();
733 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
734 			  net->dev_base_seq;
735 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
736 			if (idx < s_idx)
737 				goto cont;
738 			idev = __in6_dev_get(dev);
739 			if (!idev)
740 				goto cont;
741 
742 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
743 						       &idev->cnf,
744 						       NETLINK_CB(cb->skb).portid,
745 						       nlh->nlmsg_seq,
746 						       RTM_NEWNETCONF,
747 						       NLM_F_MULTI,
748 						       NETCONFA_ALL) < 0) {
749 				rcu_read_unlock();
750 				goto done;
751 			}
752 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
753 cont:
754 			idx++;
755 		}
756 		rcu_read_unlock();
757 	}
758 	if (h == NETDEV_HASHENTRIES) {
759 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
760 					       net->ipv6.devconf_all,
761 					       NETLINK_CB(cb->skb).portid,
762 					       nlh->nlmsg_seq,
763 					       RTM_NEWNETCONF, NLM_F_MULTI,
764 					       NETCONFA_ALL) < 0)
765 			goto done;
766 		else
767 			h++;
768 	}
769 	if (h == NETDEV_HASHENTRIES + 1) {
770 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
771 					       net->ipv6.devconf_dflt,
772 					       NETLINK_CB(cb->skb).portid,
773 					       nlh->nlmsg_seq,
774 					       RTM_NEWNETCONF, NLM_F_MULTI,
775 					       NETCONFA_ALL) < 0)
776 			goto done;
777 		else
778 			h++;
779 	}
780 done:
781 	cb->args[0] = h;
782 	cb->args[1] = idx;
783 
784 	return skb->len;
785 }
786 
787 #ifdef CONFIG_SYSCTL
788 static void dev_forward_change(struct inet6_dev *idev)
789 {
790 	struct net_device *dev;
791 	struct inet6_ifaddr *ifa;
792 
793 	if (!idev)
794 		return;
795 	dev = idev->dev;
796 	if (idev->cnf.forwarding)
797 		dev_disable_lro(dev);
798 	if (dev->flags & IFF_MULTICAST) {
799 		if (idev->cnf.forwarding) {
800 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
801 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
802 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
803 		} else {
804 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
805 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
806 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
807 		}
808 	}
809 
810 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
811 		if (ifa->flags&IFA_F_TENTATIVE)
812 			continue;
813 		if (idev->cnf.forwarding)
814 			addrconf_join_anycast(ifa);
815 		else
816 			addrconf_leave_anycast(ifa);
817 	}
818 	inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
819 				     NETCONFA_FORWARDING,
820 				     dev->ifindex, &idev->cnf);
821 }
822 
823 
824 static void addrconf_forward_change(struct net *net, __s32 newf)
825 {
826 	struct net_device *dev;
827 	struct inet6_dev *idev;
828 
829 	for_each_netdev(net, dev) {
830 		idev = __in6_dev_get(dev);
831 		if (idev) {
832 			int changed = (!idev->cnf.forwarding) ^ (!newf);
833 			idev->cnf.forwarding = newf;
834 			if (changed)
835 				dev_forward_change(idev);
836 		}
837 	}
838 }
839 
840 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
841 {
842 	struct net *net;
843 	int old;
844 
845 	if (!rtnl_trylock())
846 		return restart_syscall();
847 
848 	net = (struct net *)table->extra2;
849 	old = *p;
850 	*p = newf;
851 
852 	if (p == &net->ipv6.devconf_dflt->forwarding) {
853 		if ((!newf) ^ (!old))
854 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
855 						     NETCONFA_FORWARDING,
856 						     NETCONFA_IFINDEX_DEFAULT,
857 						     net->ipv6.devconf_dflt);
858 		rtnl_unlock();
859 		return 0;
860 	}
861 
862 	if (p == &net->ipv6.devconf_all->forwarding) {
863 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
864 
865 		net->ipv6.devconf_dflt->forwarding = newf;
866 		if ((!newf) ^ (!old_dflt))
867 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
868 						     NETCONFA_FORWARDING,
869 						     NETCONFA_IFINDEX_DEFAULT,
870 						     net->ipv6.devconf_dflt);
871 
872 		addrconf_forward_change(net, newf);
873 		if ((!newf) ^ (!old))
874 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
875 						     NETCONFA_FORWARDING,
876 						     NETCONFA_IFINDEX_ALL,
877 						     net->ipv6.devconf_all);
878 	} else if ((!newf) ^ (!old))
879 		dev_forward_change((struct inet6_dev *)table->extra1);
880 	rtnl_unlock();
881 
882 	if (newf)
883 		rt6_purge_dflt_routers(net);
884 	return 1;
885 }
886 
887 static void addrconf_linkdown_change(struct net *net, __s32 newf)
888 {
889 	struct net_device *dev;
890 	struct inet6_dev *idev;
891 
892 	for_each_netdev(net, dev) {
893 		idev = __in6_dev_get(dev);
894 		if (idev) {
895 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
896 
897 			idev->cnf.ignore_routes_with_linkdown = newf;
898 			if (changed)
899 				inet6_netconf_notify_devconf(dev_net(dev),
900 							     RTM_NEWNETCONF,
901 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
902 							     dev->ifindex,
903 							     &idev->cnf);
904 		}
905 	}
906 }
907 
908 static int addrconf_fixup_linkdown(struct ctl_table *table, int *p, int newf)
909 {
910 	struct net *net;
911 	int old;
912 
913 	if (!rtnl_trylock())
914 		return restart_syscall();
915 
916 	net = (struct net *)table->extra2;
917 	old = *p;
918 	*p = newf;
919 
920 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
921 		if ((!newf) ^ (!old))
922 			inet6_netconf_notify_devconf(net,
923 						     RTM_NEWNETCONF,
924 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
925 						     NETCONFA_IFINDEX_DEFAULT,
926 						     net->ipv6.devconf_dflt);
927 		rtnl_unlock();
928 		return 0;
929 	}
930 
931 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
932 		net->ipv6.devconf_dflt->ignore_routes_with_linkdown = newf;
933 		addrconf_linkdown_change(net, newf);
934 		if ((!newf) ^ (!old))
935 			inet6_netconf_notify_devconf(net,
936 						     RTM_NEWNETCONF,
937 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
938 						     NETCONFA_IFINDEX_ALL,
939 						     net->ipv6.devconf_all);
940 	}
941 	rtnl_unlock();
942 
943 	return 1;
944 }
945 
946 #endif
947 
948 /* Nobody refers to this ifaddr, destroy it */
949 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
950 {
951 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
952 
953 #ifdef NET_REFCNT_DEBUG
954 	pr_debug("%s\n", __func__);
955 #endif
956 
957 	in6_dev_put(ifp->idev);
958 
959 	if (cancel_delayed_work(&ifp->dad_work))
960 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
961 			  ifp);
962 
963 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
964 		pr_warn("Freeing alive inet6 address %p\n", ifp);
965 		return;
966 	}
967 
968 	kfree_rcu(ifp, rcu);
969 }
970 
971 static void
972 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
973 {
974 	struct list_head *p;
975 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
976 
977 	/*
978 	 * Each device address list is sorted in order of scope -
979 	 * global before linklocal.
980 	 */
981 	list_for_each(p, &idev->addr_list) {
982 		struct inet6_ifaddr *ifa
983 			= list_entry(p, struct inet6_ifaddr, if_list);
984 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
985 			break;
986 	}
987 
988 	list_add_tail_rcu(&ifp->if_list, p);
989 }
990 
991 static u32 inet6_addr_hash(const struct net *net, const struct in6_addr *addr)
992 {
993 	u32 val = ipv6_addr_hash(addr) ^ net_hash_mix(net);
994 
995 	return hash_32(val, IN6_ADDR_HSIZE_SHIFT);
996 }
997 
998 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
999 			       struct net_device *dev, unsigned int hash)
1000 {
1001 	struct inet6_ifaddr *ifp;
1002 
1003 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
1004 		if (!net_eq(dev_net(ifp->idev->dev), net))
1005 			continue;
1006 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1007 			if (!dev || ifp->idev->dev == dev)
1008 				return true;
1009 		}
1010 	}
1011 	return false;
1012 }
1013 
1014 static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
1015 {
1016 	unsigned int hash = inet6_addr_hash(dev_net(dev), &ifa->addr);
1017 	int err = 0;
1018 
1019 	spin_lock(&addrconf_hash_lock);
1020 
1021 	/* Ignore adding duplicate addresses on an interface */
1022 	if (ipv6_chk_same_addr(dev_net(dev), &ifa->addr, dev, hash)) {
1023 		netdev_dbg(dev, "ipv6_add_addr: already assigned\n");
1024 		err = -EEXIST;
1025 	} else {
1026 		hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
1027 	}
1028 
1029 	spin_unlock(&addrconf_hash_lock);
1030 
1031 	return err;
1032 }
1033 
1034 /* On success it returns ifp with increased reference count */
1035 
1036 static struct inet6_ifaddr *
1037 ipv6_add_addr(struct inet6_dev *idev, struct ifa6_config *cfg,
1038 	      bool can_block, struct netlink_ext_ack *extack)
1039 {
1040 	gfp_t gfp_flags = can_block ? GFP_KERNEL : GFP_ATOMIC;
1041 	int addr_type = ipv6_addr_type(cfg->pfx);
1042 	struct net *net = dev_net(idev->dev);
1043 	struct inet6_ifaddr *ifa = NULL;
1044 	struct fib6_info *f6i = NULL;
1045 	int err = 0;
1046 
1047 	if (addr_type == IPV6_ADDR_ANY ||
1048 	    (addr_type & IPV6_ADDR_MULTICAST &&
1049 	     !(cfg->ifa_flags & IFA_F_MCAUTOJOIN)) ||
1050 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
1051 	     !netif_is_l3_master(idev->dev) &&
1052 	     addr_type & IPV6_ADDR_LOOPBACK))
1053 		return ERR_PTR(-EADDRNOTAVAIL);
1054 
1055 	if (idev->dead) {
1056 		err = -ENODEV;			/*XXX*/
1057 		goto out;
1058 	}
1059 
1060 	if (idev->cnf.disable_ipv6) {
1061 		err = -EACCES;
1062 		goto out;
1063 	}
1064 
1065 	/* validator notifier needs to be blocking;
1066 	 * do not call in atomic context
1067 	 */
1068 	if (can_block) {
1069 		struct in6_validator_info i6vi = {
1070 			.i6vi_addr = *cfg->pfx,
1071 			.i6vi_dev = idev,
1072 			.extack = extack,
1073 		};
1074 
1075 		err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
1076 		err = notifier_to_errno(err);
1077 		if (err < 0)
1078 			goto out;
1079 	}
1080 
1081 	ifa = kzalloc(sizeof(*ifa), gfp_flags);
1082 	if (!ifa) {
1083 		err = -ENOBUFS;
1084 		goto out;
1085 	}
1086 
1087 	f6i = addrconf_f6i_alloc(net, idev, cfg->pfx, false, gfp_flags);
1088 	if (IS_ERR(f6i)) {
1089 		err = PTR_ERR(f6i);
1090 		f6i = NULL;
1091 		goto out;
1092 	}
1093 
1094 	if (net->ipv6.devconf_all->disable_policy ||
1095 	    idev->cnf.disable_policy)
1096 		f6i->dst_nopolicy = true;
1097 
1098 	neigh_parms_data_state_setall(idev->nd_parms);
1099 
1100 	ifa->addr = *cfg->pfx;
1101 	if (cfg->peer_pfx)
1102 		ifa->peer_addr = *cfg->peer_pfx;
1103 
1104 	spin_lock_init(&ifa->lock);
1105 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1106 	INIT_HLIST_NODE(&ifa->addr_lst);
1107 	ifa->scope = cfg->scope;
1108 	ifa->prefix_len = cfg->plen;
1109 	ifa->rt_priority = cfg->rt_priority;
1110 	ifa->flags = cfg->ifa_flags;
1111 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1112 	if (!(cfg->ifa_flags & IFA_F_NODAD))
1113 		ifa->flags |= IFA_F_TENTATIVE;
1114 	ifa->valid_lft = cfg->valid_lft;
1115 	ifa->prefered_lft = cfg->preferred_lft;
1116 	ifa->cstamp = ifa->tstamp = jiffies;
1117 	ifa->tokenized = false;
1118 
1119 	ifa->rt = f6i;
1120 
1121 	ifa->idev = idev;
1122 	in6_dev_hold(idev);
1123 
1124 	/* For caller */
1125 	refcount_set(&ifa->refcnt, 1);
1126 
1127 	rcu_read_lock_bh();
1128 
1129 	err = ipv6_add_addr_hash(idev->dev, ifa);
1130 	if (err < 0) {
1131 		rcu_read_unlock_bh();
1132 		goto out;
1133 	}
1134 
1135 	write_lock(&idev->lock);
1136 
1137 	/* Add to inet6_dev unicast addr list. */
1138 	ipv6_link_dev_addr(idev, ifa);
1139 
1140 	if (ifa->flags&IFA_F_TEMPORARY) {
1141 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1142 		in6_ifa_hold(ifa);
1143 	}
1144 
1145 	in6_ifa_hold(ifa);
1146 	write_unlock(&idev->lock);
1147 
1148 	rcu_read_unlock_bh();
1149 
1150 	inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1151 out:
1152 	if (unlikely(err < 0)) {
1153 		fib6_info_release(f6i);
1154 
1155 		if (ifa) {
1156 			if (ifa->idev)
1157 				in6_dev_put(ifa->idev);
1158 			kfree(ifa);
1159 		}
1160 		ifa = ERR_PTR(err);
1161 	}
1162 
1163 	return ifa;
1164 }
1165 
1166 enum cleanup_prefix_rt_t {
1167 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1168 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1169 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1170 };
1171 
1172 /*
1173  * Check, whether the prefix for ifp would still need a prefix route
1174  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1175  * constants.
1176  *
1177  * 1) we don't purge prefix if address was not permanent.
1178  *    prefix is managed by its own lifetime.
1179  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1180  * 3) if there are no addresses, delete prefix.
1181  * 4) if there are still other permanent address(es),
1182  *    corresponding prefix is still permanent.
1183  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1184  *    don't purge the prefix, assume user space is managing it.
1185  * 6) otherwise, update prefix lifetime to the
1186  *    longest valid lifetime among the corresponding
1187  *    addresses on the device.
1188  *    Note: subsequent RA will update lifetime.
1189  **/
1190 static enum cleanup_prefix_rt_t
1191 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1192 {
1193 	struct inet6_ifaddr *ifa;
1194 	struct inet6_dev *idev = ifp->idev;
1195 	unsigned long lifetime;
1196 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1197 
1198 	*expires = jiffies;
1199 
1200 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1201 		if (ifa == ifp)
1202 			continue;
1203 		if (ifa->prefix_len != ifp->prefix_len ||
1204 		    !ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1205 				       ifp->prefix_len))
1206 			continue;
1207 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1208 			return CLEANUP_PREFIX_RT_NOP;
1209 
1210 		action = CLEANUP_PREFIX_RT_EXPIRE;
1211 
1212 		spin_lock(&ifa->lock);
1213 
1214 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1215 		/*
1216 		 * Note: Because this address is
1217 		 * not permanent, lifetime <
1218 		 * LONG_MAX / HZ here.
1219 		 */
1220 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1221 			*expires = ifa->tstamp + lifetime * HZ;
1222 		spin_unlock(&ifa->lock);
1223 	}
1224 
1225 	return action;
1226 }
1227 
1228 static void
1229 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires,
1230 		     bool del_rt, bool del_peer)
1231 {
1232 	struct fib6_info *f6i;
1233 
1234 	f6i = addrconf_get_prefix_route(del_peer ? &ifp->peer_addr : &ifp->addr,
1235 					ifp->prefix_len,
1236 					ifp->idev->dev, 0, RTF_DEFAULT, true);
1237 	if (f6i) {
1238 		if (del_rt)
1239 			ip6_del_rt(dev_net(ifp->idev->dev), f6i);
1240 		else {
1241 			if (!(f6i->fib6_flags & RTF_EXPIRES))
1242 				fib6_set_expires(f6i, expires);
1243 			fib6_info_release(f6i);
1244 		}
1245 	}
1246 }
1247 
1248 
1249 /* This function wants to get referenced ifp and releases it before return */
1250 
1251 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1252 {
1253 	int state;
1254 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1255 	unsigned long expires;
1256 
1257 	ASSERT_RTNL();
1258 
1259 	spin_lock_bh(&ifp->lock);
1260 	state = ifp->state;
1261 	ifp->state = INET6_IFADDR_STATE_DEAD;
1262 	spin_unlock_bh(&ifp->lock);
1263 
1264 	if (state == INET6_IFADDR_STATE_DEAD)
1265 		goto out;
1266 
1267 	spin_lock_bh(&addrconf_hash_lock);
1268 	hlist_del_init_rcu(&ifp->addr_lst);
1269 	spin_unlock_bh(&addrconf_hash_lock);
1270 
1271 	write_lock_bh(&ifp->idev->lock);
1272 
1273 	if (ifp->flags&IFA_F_TEMPORARY) {
1274 		list_del(&ifp->tmp_list);
1275 		if (ifp->ifpub) {
1276 			in6_ifa_put(ifp->ifpub);
1277 			ifp->ifpub = NULL;
1278 		}
1279 		__in6_ifa_put(ifp);
1280 	}
1281 
1282 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1283 		action = check_cleanup_prefix_route(ifp, &expires);
1284 
1285 	list_del_rcu(&ifp->if_list);
1286 	__in6_ifa_put(ifp);
1287 
1288 	write_unlock_bh(&ifp->idev->lock);
1289 
1290 	addrconf_del_dad_work(ifp);
1291 
1292 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1293 
1294 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1295 
1296 	if (action != CLEANUP_PREFIX_RT_NOP) {
1297 		cleanup_prefix_route(ifp, expires,
1298 			action == CLEANUP_PREFIX_RT_DEL, false);
1299 	}
1300 
1301 	/* clean up prefsrc entries */
1302 	rt6_remove_prefsrc(ifp);
1303 out:
1304 	in6_ifa_put(ifp);
1305 }
1306 
1307 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp,
1308 				struct inet6_ifaddr *ift,
1309 				bool block)
1310 {
1311 	struct inet6_dev *idev = ifp->idev;
1312 	struct in6_addr addr, *tmpaddr;
1313 	unsigned long tmp_tstamp, age;
1314 	unsigned long regen_advance;
1315 	struct ifa6_config cfg;
1316 	int ret = 0;
1317 	unsigned long now = jiffies;
1318 	long max_desync_factor;
1319 	s32 cnf_temp_preferred_lft;
1320 
1321 	write_lock_bh(&idev->lock);
1322 	if (ift) {
1323 		spin_lock_bh(&ift->lock);
1324 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
1325 		spin_unlock_bh(&ift->lock);
1326 		tmpaddr = &addr;
1327 	} else {
1328 		tmpaddr = NULL;
1329 	}
1330 retry:
1331 	in6_dev_hold(idev);
1332 	if (idev->cnf.use_tempaddr <= 0) {
1333 		write_unlock_bh(&idev->lock);
1334 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1335 		in6_dev_put(idev);
1336 		ret = -1;
1337 		goto out;
1338 	}
1339 	spin_lock_bh(&ifp->lock);
1340 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1341 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1342 		spin_unlock_bh(&ifp->lock);
1343 		write_unlock_bh(&idev->lock);
1344 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1345 			__func__);
1346 		in6_dev_put(idev);
1347 		ret = -1;
1348 		goto out;
1349 	}
1350 	in6_ifa_hold(ifp);
1351 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1352 	ipv6_try_regen_rndid(idev, tmpaddr);
1353 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1354 	age = (now - ifp->tstamp) / HZ;
1355 
1356 	regen_advance = idev->cnf.regen_max_retry *
1357 			idev->cnf.dad_transmits *
1358 			NEIGH_VAR(idev->nd_parms, RETRANS_TIME) / HZ;
1359 
1360 	/* recalculate max_desync_factor each time and update
1361 	 * idev->desync_factor if it's larger
1362 	 */
1363 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1364 	max_desync_factor = min_t(__u32,
1365 				  idev->cnf.max_desync_factor,
1366 				  cnf_temp_preferred_lft - regen_advance);
1367 
1368 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1369 		if (max_desync_factor > 0) {
1370 			get_random_bytes(&idev->desync_factor,
1371 					 sizeof(idev->desync_factor));
1372 			idev->desync_factor %= max_desync_factor;
1373 		} else {
1374 			idev->desync_factor = 0;
1375 		}
1376 	}
1377 
1378 	memset(&cfg, 0, sizeof(cfg));
1379 	cfg.valid_lft = min_t(__u32, ifp->valid_lft,
1380 			      idev->cnf.temp_valid_lft + age);
1381 	cfg.preferred_lft = cnf_temp_preferred_lft + age - idev->desync_factor;
1382 	cfg.preferred_lft = min_t(__u32, ifp->prefered_lft, cfg.preferred_lft);
1383 
1384 	cfg.plen = ifp->prefix_len;
1385 	tmp_tstamp = ifp->tstamp;
1386 	spin_unlock_bh(&ifp->lock);
1387 
1388 	write_unlock_bh(&idev->lock);
1389 
1390 	/* A temporary address is created only if this calculated Preferred
1391 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1392 	 * an implementation must not create a temporary address with a zero
1393 	 * Preferred Lifetime.
1394 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1395 	 * temporary addresses being generated.
1396 	 */
1397 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1398 	if (cfg.preferred_lft <= regen_advance + age) {
1399 		in6_ifa_put(ifp);
1400 		in6_dev_put(idev);
1401 		ret = -1;
1402 		goto out;
1403 	}
1404 
1405 	cfg.ifa_flags = IFA_F_TEMPORARY;
1406 	/* set in addrconf_prefix_rcv() */
1407 	if (ifp->flags & IFA_F_OPTIMISTIC)
1408 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
1409 
1410 	cfg.pfx = &addr;
1411 	cfg.scope = ipv6_addr_scope(cfg.pfx);
1412 
1413 	ift = ipv6_add_addr(idev, &cfg, block, NULL);
1414 	if (IS_ERR(ift)) {
1415 		in6_ifa_put(ifp);
1416 		in6_dev_put(idev);
1417 		pr_info("%s: retry temporary address regeneration\n", __func__);
1418 		tmpaddr = &addr;
1419 		write_lock_bh(&idev->lock);
1420 		goto retry;
1421 	}
1422 
1423 	spin_lock_bh(&ift->lock);
1424 	ift->ifpub = ifp;
1425 	ift->cstamp = now;
1426 	ift->tstamp = tmp_tstamp;
1427 	spin_unlock_bh(&ift->lock);
1428 
1429 	addrconf_dad_start(ift);
1430 	in6_ifa_put(ift);
1431 	in6_dev_put(idev);
1432 out:
1433 	return ret;
1434 }
1435 
1436 /*
1437  *	Choose an appropriate source address (RFC3484)
1438  */
1439 enum {
1440 	IPV6_SADDR_RULE_INIT = 0,
1441 	IPV6_SADDR_RULE_LOCAL,
1442 	IPV6_SADDR_RULE_SCOPE,
1443 	IPV6_SADDR_RULE_PREFERRED,
1444 #ifdef CONFIG_IPV6_MIP6
1445 	IPV6_SADDR_RULE_HOA,
1446 #endif
1447 	IPV6_SADDR_RULE_OIF,
1448 	IPV6_SADDR_RULE_LABEL,
1449 	IPV6_SADDR_RULE_PRIVACY,
1450 	IPV6_SADDR_RULE_ORCHID,
1451 	IPV6_SADDR_RULE_PREFIX,
1452 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1453 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1454 #endif
1455 	IPV6_SADDR_RULE_MAX
1456 };
1457 
1458 struct ipv6_saddr_score {
1459 	int			rule;
1460 	int			addr_type;
1461 	struct inet6_ifaddr	*ifa;
1462 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1463 	int			scopedist;
1464 	int			matchlen;
1465 };
1466 
1467 struct ipv6_saddr_dst {
1468 	const struct in6_addr *addr;
1469 	int ifindex;
1470 	int scope;
1471 	int label;
1472 	unsigned int prefs;
1473 };
1474 
1475 static inline int ipv6_saddr_preferred(int type)
1476 {
1477 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1478 		return 1;
1479 	return 0;
1480 }
1481 
1482 static bool ipv6_use_optimistic_addr(struct net *net,
1483 				     struct inet6_dev *idev)
1484 {
1485 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1486 	if (!idev)
1487 		return false;
1488 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1489 		return false;
1490 	if (!net->ipv6.devconf_all->use_optimistic && !idev->cnf.use_optimistic)
1491 		return false;
1492 
1493 	return true;
1494 #else
1495 	return false;
1496 #endif
1497 }
1498 
1499 static bool ipv6_allow_optimistic_dad(struct net *net,
1500 				      struct inet6_dev *idev)
1501 {
1502 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1503 	if (!idev)
1504 		return false;
1505 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1506 		return false;
1507 
1508 	return true;
1509 #else
1510 	return false;
1511 #endif
1512 }
1513 
1514 static int ipv6_get_saddr_eval(struct net *net,
1515 			       struct ipv6_saddr_score *score,
1516 			       struct ipv6_saddr_dst *dst,
1517 			       int i)
1518 {
1519 	int ret;
1520 
1521 	if (i <= score->rule) {
1522 		switch (i) {
1523 		case IPV6_SADDR_RULE_SCOPE:
1524 			ret = score->scopedist;
1525 			break;
1526 		case IPV6_SADDR_RULE_PREFIX:
1527 			ret = score->matchlen;
1528 			break;
1529 		default:
1530 			ret = !!test_bit(i, score->scorebits);
1531 		}
1532 		goto out;
1533 	}
1534 
1535 	switch (i) {
1536 	case IPV6_SADDR_RULE_INIT:
1537 		/* Rule 0: remember if hiscore is not ready yet */
1538 		ret = !!score->ifa;
1539 		break;
1540 	case IPV6_SADDR_RULE_LOCAL:
1541 		/* Rule 1: Prefer same address */
1542 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1543 		break;
1544 	case IPV6_SADDR_RULE_SCOPE:
1545 		/* Rule 2: Prefer appropriate scope
1546 		 *
1547 		 *      ret
1548 		 *       ^
1549 		 *    -1 |  d 15
1550 		 *    ---+--+-+---> scope
1551 		 *       |
1552 		 *       |             d is scope of the destination.
1553 		 *  B-d  |  \
1554 		 *       |   \      <- smaller scope is better if
1555 		 *  B-15 |    \        if scope is enough for destination.
1556 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1557 		 * d-C-1 | /
1558 		 *       |/         <- greater is better
1559 		 *   -C  /             if scope is not enough for destination.
1560 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1561 		 *
1562 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1563 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1564 		 * Assume B = 0 and we get C > 29.
1565 		 */
1566 		ret = __ipv6_addr_src_scope(score->addr_type);
1567 		if (ret >= dst->scope)
1568 			ret = -ret;
1569 		else
1570 			ret -= 128;	/* 30 is enough */
1571 		score->scopedist = ret;
1572 		break;
1573 	case IPV6_SADDR_RULE_PREFERRED:
1574 	    {
1575 		/* Rule 3: Avoid deprecated and optimistic addresses */
1576 		u8 avoid = IFA_F_DEPRECATED;
1577 
1578 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1579 			avoid |= IFA_F_OPTIMISTIC;
1580 		ret = ipv6_saddr_preferred(score->addr_type) ||
1581 		      !(score->ifa->flags & avoid);
1582 		break;
1583 	    }
1584 #ifdef CONFIG_IPV6_MIP6
1585 	case IPV6_SADDR_RULE_HOA:
1586 	    {
1587 		/* Rule 4: Prefer home address */
1588 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1589 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1590 		break;
1591 	    }
1592 #endif
1593 	case IPV6_SADDR_RULE_OIF:
1594 		/* Rule 5: Prefer outgoing interface */
1595 		ret = (!dst->ifindex ||
1596 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1597 		break;
1598 	case IPV6_SADDR_RULE_LABEL:
1599 		/* Rule 6: Prefer matching label */
1600 		ret = ipv6_addr_label(net,
1601 				      &score->ifa->addr, score->addr_type,
1602 				      score->ifa->idev->dev->ifindex) == dst->label;
1603 		break;
1604 	case IPV6_SADDR_RULE_PRIVACY:
1605 	    {
1606 		/* Rule 7: Prefer public address
1607 		 * Note: prefer temporary address if use_tempaddr >= 2
1608 		 */
1609 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1610 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1611 				score->ifa->idev->cnf.use_tempaddr >= 2;
1612 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1613 		break;
1614 	    }
1615 	case IPV6_SADDR_RULE_ORCHID:
1616 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1617 		 *	    non-ORCHID vs non-ORCHID
1618 		 */
1619 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1620 			ipv6_addr_orchid(dst->addr));
1621 		break;
1622 	case IPV6_SADDR_RULE_PREFIX:
1623 		/* Rule 8: Use longest matching prefix */
1624 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1625 		if (ret > score->ifa->prefix_len)
1626 			ret = score->ifa->prefix_len;
1627 		score->matchlen = ret;
1628 		break;
1629 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1630 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1631 		/* Optimistic addresses still have lower precedence than other
1632 		 * preferred addresses.
1633 		 */
1634 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1635 		break;
1636 #endif
1637 	default:
1638 		ret = 0;
1639 	}
1640 
1641 	if (ret)
1642 		__set_bit(i, score->scorebits);
1643 	score->rule = i;
1644 out:
1645 	return ret;
1646 }
1647 
1648 static int __ipv6_dev_get_saddr(struct net *net,
1649 				struct ipv6_saddr_dst *dst,
1650 				struct inet6_dev *idev,
1651 				struct ipv6_saddr_score *scores,
1652 				int hiscore_idx)
1653 {
1654 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1655 
1656 	list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1657 		int i;
1658 
1659 		/*
1660 		 * - Tentative Address (RFC2462 section 5.4)
1661 		 *  - A tentative address is not considered
1662 		 *    "assigned to an interface" in the traditional
1663 		 *    sense, unless it is also flagged as optimistic.
1664 		 * - Candidate Source Address (section 4)
1665 		 *  - In any case, anycast addresses, multicast
1666 		 *    addresses, and the unspecified address MUST
1667 		 *    NOT be included in a candidate set.
1668 		 */
1669 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1670 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1671 			continue;
1672 
1673 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1674 
1675 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1676 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1677 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1678 					    idev->dev->name);
1679 			continue;
1680 		}
1681 
1682 		score->rule = -1;
1683 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1684 
1685 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1686 			int minihiscore, miniscore;
1687 
1688 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1689 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1690 
1691 			if (minihiscore > miniscore) {
1692 				if (i == IPV6_SADDR_RULE_SCOPE &&
1693 				    score->scopedist > 0) {
1694 					/*
1695 					 * special case:
1696 					 * each remaining entry
1697 					 * has too small (not enough)
1698 					 * scope, because ifa entries
1699 					 * are sorted by their scope
1700 					 * values.
1701 					 */
1702 					goto out;
1703 				}
1704 				break;
1705 			} else if (minihiscore < miniscore) {
1706 				swap(hiscore, score);
1707 				hiscore_idx = 1 - hiscore_idx;
1708 
1709 				/* restore our iterator */
1710 				score->ifa = hiscore->ifa;
1711 
1712 				break;
1713 			}
1714 		}
1715 	}
1716 out:
1717 	return hiscore_idx;
1718 }
1719 
1720 static int ipv6_get_saddr_master(struct net *net,
1721 				 const struct net_device *dst_dev,
1722 				 const struct net_device *master,
1723 				 struct ipv6_saddr_dst *dst,
1724 				 struct ipv6_saddr_score *scores,
1725 				 int hiscore_idx)
1726 {
1727 	struct inet6_dev *idev;
1728 
1729 	idev = __in6_dev_get(dst_dev);
1730 	if (idev)
1731 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1732 						   scores, hiscore_idx);
1733 
1734 	idev = __in6_dev_get(master);
1735 	if (idev)
1736 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1737 						   scores, hiscore_idx);
1738 
1739 	return hiscore_idx;
1740 }
1741 
1742 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1743 		       const struct in6_addr *daddr, unsigned int prefs,
1744 		       struct in6_addr *saddr)
1745 {
1746 	struct ipv6_saddr_score scores[2], *hiscore;
1747 	struct ipv6_saddr_dst dst;
1748 	struct inet6_dev *idev;
1749 	struct net_device *dev;
1750 	int dst_type;
1751 	bool use_oif_addr = false;
1752 	int hiscore_idx = 0;
1753 	int ret = 0;
1754 
1755 	dst_type = __ipv6_addr_type(daddr);
1756 	dst.addr = daddr;
1757 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1758 	dst.scope = __ipv6_addr_src_scope(dst_type);
1759 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1760 	dst.prefs = prefs;
1761 
1762 	scores[hiscore_idx].rule = -1;
1763 	scores[hiscore_idx].ifa = NULL;
1764 
1765 	rcu_read_lock();
1766 
1767 	/* Candidate Source Address (section 4)
1768 	 *  - multicast and link-local destination address,
1769 	 *    the set of candidate source address MUST only
1770 	 *    include addresses assigned to interfaces
1771 	 *    belonging to the same link as the outgoing
1772 	 *    interface.
1773 	 * (- For site-local destination addresses, the
1774 	 *    set of candidate source addresses MUST only
1775 	 *    include addresses assigned to interfaces
1776 	 *    belonging to the same site as the outgoing
1777 	 *    interface.)
1778 	 *  - "It is RECOMMENDED that the candidate source addresses
1779 	 *    be the set of unicast addresses assigned to the
1780 	 *    interface that will be used to send to the destination
1781 	 *    (the 'outgoing' interface)." (RFC 6724)
1782 	 */
1783 	if (dst_dev) {
1784 		idev = __in6_dev_get(dst_dev);
1785 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1786 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1787 		    (idev && idev->cnf.use_oif_addrs_only)) {
1788 			use_oif_addr = true;
1789 		}
1790 	}
1791 
1792 	if (use_oif_addr) {
1793 		if (idev)
1794 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1795 	} else {
1796 		const struct net_device *master;
1797 		int master_idx = 0;
1798 
1799 		/* if dst_dev exists and is enslaved to an L3 device, then
1800 		 * prefer addresses from dst_dev and then the master over
1801 		 * any other enslaved devices in the L3 domain.
1802 		 */
1803 		master = l3mdev_master_dev_rcu(dst_dev);
1804 		if (master) {
1805 			master_idx = master->ifindex;
1806 
1807 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1808 							    master, &dst,
1809 							    scores, hiscore_idx);
1810 
1811 			if (scores[hiscore_idx].ifa)
1812 				goto out;
1813 		}
1814 
1815 		for_each_netdev_rcu(net, dev) {
1816 			/* only consider addresses on devices in the
1817 			 * same L3 domain
1818 			 */
1819 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1820 				continue;
1821 			idev = __in6_dev_get(dev);
1822 			if (!idev)
1823 				continue;
1824 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1825 		}
1826 	}
1827 
1828 out:
1829 	hiscore = &scores[hiscore_idx];
1830 	if (!hiscore->ifa)
1831 		ret = -EADDRNOTAVAIL;
1832 	else
1833 		*saddr = hiscore->ifa->addr;
1834 
1835 	rcu_read_unlock();
1836 	return ret;
1837 }
1838 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1839 
1840 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1841 		      u32 banned_flags)
1842 {
1843 	struct inet6_ifaddr *ifp;
1844 	int err = -EADDRNOTAVAIL;
1845 
1846 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1847 		if (ifp->scope > IFA_LINK)
1848 			break;
1849 		if (ifp->scope == IFA_LINK &&
1850 		    !(ifp->flags & banned_flags)) {
1851 			*addr = ifp->addr;
1852 			err = 0;
1853 			break;
1854 		}
1855 	}
1856 	return err;
1857 }
1858 
1859 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1860 		    u32 banned_flags)
1861 {
1862 	struct inet6_dev *idev;
1863 	int err = -EADDRNOTAVAIL;
1864 
1865 	rcu_read_lock();
1866 	idev = __in6_dev_get(dev);
1867 	if (idev) {
1868 		read_lock_bh(&idev->lock);
1869 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1870 		read_unlock_bh(&idev->lock);
1871 	}
1872 	rcu_read_unlock();
1873 	return err;
1874 }
1875 
1876 static int ipv6_count_addresses(const struct inet6_dev *idev)
1877 {
1878 	const struct inet6_ifaddr *ifp;
1879 	int cnt = 0;
1880 
1881 	rcu_read_lock();
1882 	list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1883 		cnt++;
1884 	rcu_read_unlock();
1885 	return cnt;
1886 }
1887 
1888 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1889 		  const struct net_device *dev, int strict)
1890 {
1891 	return ipv6_chk_addr_and_flags(net, addr, dev, !dev,
1892 				       strict, IFA_F_TENTATIVE);
1893 }
1894 EXPORT_SYMBOL(ipv6_chk_addr);
1895 
1896 /* device argument is used to find the L3 domain of interest. If
1897  * skip_dev_check is set, then the ifp device is not checked against
1898  * the passed in dev argument. So the 2 cases for addresses checks are:
1899  *   1. does the address exist in the L3 domain that dev is part of
1900  *      (skip_dev_check = true), or
1901  *
1902  *   2. does the address exist on the specific device
1903  *      (skip_dev_check = false)
1904  */
1905 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1906 			    const struct net_device *dev, bool skip_dev_check,
1907 			    int strict, u32 banned_flags)
1908 {
1909 	unsigned int hash = inet6_addr_hash(net, addr);
1910 	const struct net_device *l3mdev;
1911 	struct inet6_ifaddr *ifp;
1912 	u32 ifp_flags;
1913 
1914 	rcu_read_lock();
1915 
1916 	l3mdev = l3mdev_master_dev_rcu(dev);
1917 	if (skip_dev_check)
1918 		dev = NULL;
1919 
1920 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1921 		if (!net_eq(dev_net(ifp->idev->dev), net))
1922 			continue;
1923 
1924 		if (l3mdev_master_dev_rcu(ifp->idev->dev) != l3mdev)
1925 			continue;
1926 
1927 		/* Decouple optimistic from tentative for evaluation here.
1928 		 * Ban optimistic addresses explicitly, when required.
1929 		 */
1930 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1931 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1932 			    : ifp->flags;
1933 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1934 		    !(ifp_flags&banned_flags) &&
1935 		    (!dev || ifp->idev->dev == dev ||
1936 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1937 			rcu_read_unlock();
1938 			return 1;
1939 		}
1940 	}
1941 
1942 	rcu_read_unlock();
1943 	return 0;
1944 }
1945 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
1946 
1947 
1948 /* Compares an address/prefix_len with addresses on device @dev.
1949  * If one is found it returns true.
1950  */
1951 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1952 	const unsigned int prefix_len, struct net_device *dev)
1953 {
1954 	const struct inet6_ifaddr *ifa;
1955 	const struct inet6_dev *idev;
1956 	bool ret = false;
1957 
1958 	rcu_read_lock();
1959 	idev = __in6_dev_get(dev);
1960 	if (idev) {
1961 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1962 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1963 			if (ret)
1964 				break;
1965 		}
1966 	}
1967 	rcu_read_unlock();
1968 
1969 	return ret;
1970 }
1971 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1972 
1973 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1974 {
1975 	const struct inet6_ifaddr *ifa;
1976 	const struct inet6_dev *idev;
1977 	int	onlink;
1978 
1979 	onlink = 0;
1980 	rcu_read_lock();
1981 	idev = __in6_dev_get(dev);
1982 	if (idev) {
1983 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1984 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1985 						   ifa->prefix_len);
1986 			if (onlink)
1987 				break;
1988 		}
1989 	}
1990 	rcu_read_unlock();
1991 	return onlink;
1992 }
1993 EXPORT_SYMBOL(ipv6_chk_prefix);
1994 
1995 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1996 				     struct net_device *dev, int strict)
1997 {
1998 	unsigned int hash = inet6_addr_hash(net, addr);
1999 	struct inet6_ifaddr *ifp, *result = NULL;
2000 
2001 	rcu_read_lock();
2002 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
2003 		if (!net_eq(dev_net(ifp->idev->dev), net))
2004 			continue;
2005 		if (ipv6_addr_equal(&ifp->addr, addr)) {
2006 			if (!dev || ifp->idev->dev == dev ||
2007 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
2008 				result = ifp;
2009 				in6_ifa_hold(ifp);
2010 				break;
2011 			}
2012 		}
2013 	}
2014 	rcu_read_unlock();
2015 
2016 	return result;
2017 }
2018 
2019 /* Gets referenced address, destroys ifaddr */
2020 
2021 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
2022 {
2023 	if (dad_failed)
2024 		ifp->flags |= IFA_F_DADFAILED;
2025 
2026 	if (ifp->flags&IFA_F_TEMPORARY) {
2027 		struct inet6_ifaddr *ifpub;
2028 		spin_lock_bh(&ifp->lock);
2029 		ifpub = ifp->ifpub;
2030 		if (ifpub) {
2031 			in6_ifa_hold(ifpub);
2032 			spin_unlock_bh(&ifp->lock);
2033 			ipv6_create_tempaddr(ifpub, ifp, true);
2034 			in6_ifa_put(ifpub);
2035 		} else {
2036 			spin_unlock_bh(&ifp->lock);
2037 		}
2038 		ipv6_del_addr(ifp);
2039 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
2040 		spin_lock_bh(&ifp->lock);
2041 		addrconf_del_dad_work(ifp);
2042 		ifp->flags |= IFA_F_TENTATIVE;
2043 		if (dad_failed)
2044 			ifp->flags &= ~IFA_F_OPTIMISTIC;
2045 		spin_unlock_bh(&ifp->lock);
2046 		if (dad_failed)
2047 			ipv6_ifa_notify(0, ifp);
2048 		in6_ifa_put(ifp);
2049 	} else {
2050 		ipv6_del_addr(ifp);
2051 	}
2052 }
2053 
2054 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
2055 {
2056 	int err = -ENOENT;
2057 
2058 	spin_lock_bh(&ifp->lock);
2059 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
2060 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
2061 		err = 0;
2062 	}
2063 	spin_unlock_bh(&ifp->lock);
2064 
2065 	return err;
2066 }
2067 
2068 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp)
2069 {
2070 	struct inet6_dev *idev = ifp->idev;
2071 	struct net *net = dev_net(ifp->idev->dev);
2072 
2073 	if (addrconf_dad_end(ifp)) {
2074 		in6_ifa_put(ifp);
2075 		return;
2076 	}
2077 
2078 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c used by %pM detected!\n",
2079 			     ifp->idev->dev->name, &ifp->addr, eth_hdr(skb)->h_source);
2080 
2081 	spin_lock_bh(&ifp->lock);
2082 
2083 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2084 		struct in6_addr new_addr;
2085 		struct inet6_ifaddr *ifp2;
2086 		int retries = ifp->stable_privacy_retry + 1;
2087 		struct ifa6_config cfg = {
2088 			.pfx = &new_addr,
2089 			.plen = ifp->prefix_len,
2090 			.ifa_flags = ifp->flags,
2091 			.valid_lft = ifp->valid_lft,
2092 			.preferred_lft = ifp->prefered_lft,
2093 			.scope = ifp->scope,
2094 		};
2095 
2096 		if (retries > net->ipv6.sysctl.idgen_retries) {
2097 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2098 					     ifp->idev->dev->name);
2099 			goto errdad;
2100 		}
2101 
2102 		new_addr = ifp->addr;
2103 		if (ipv6_generate_stable_address(&new_addr, retries,
2104 						 idev))
2105 			goto errdad;
2106 
2107 		spin_unlock_bh(&ifp->lock);
2108 
2109 		if (idev->cnf.max_addresses &&
2110 		    ipv6_count_addresses(idev) >=
2111 		    idev->cnf.max_addresses)
2112 			goto lock_errdad;
2113 
2114 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2115 				     ifp->idev->dev->name);
2116 
2117 		ifp2 = ipv6_add_addr(idev, &cfg, false, NULL);
2118 		if (IS_ERR(ifp2))
2119 			goto lock_errdad;
2120 
2121 		spin_lock_bh(&ifp2->lock);
2122 		ifp2->stable_privacy_retry = retries;
2123 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2124 		spin_unlock_bh(&ifp2->lock);
2125 
2126 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2127 		in6_ifa_put(ifp2);
2128 lock_errdad:
2129 		spin_lock_bh(&ifp->lock);
2130 	}
2131 
2132 errdad:
2133 	/* transition from _POSTDAD to _ERRDAD */
2134 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2135 	spin_unlock_bh(&ifp->lock);
2136 
2137 	addrconf_mod_dad_work(ifp, 0);
2138 	in6_ifa_put(ifp);
2139 }
2140 
2141 /* Join to solicited addr multicast group.
2142  * caller must hold RTNL */
2143 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2144 {
2145 	struct in6_addr maddr;
2146 
2147 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2148 		return;
2149 
2150 	addrconf_addr_solict_mult(addr, &maddr);
2151 	ipv6_dev_mc_inc(dev, &maddr);
2152 }
2153 
2154 /* caller must hold RTNL */
2155 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2156 {
2157 	struct in6_addr maddr;
2158 
2159 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2160 		return;
2161 
2162 	addrconf_addr_solict_mult(addr, &maddr);
2163 	__ipv6_dev_mc_dec(idev, &maddr);
2164 }
2165 
2166 /* caller must hold RTNL */
2167 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2168 {
2169 	struct in6_addr addr;
2170 
2171 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2172 		return;
2173 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2174 	if (ipv6_addr_any(&addr))
2175 		return;
2176 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2177 }
2178 
2179 /* caller must hold RTNL */
2180 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2181 {
2182 	struct in6_addr addr;
2183 
2184 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2185 		return;
2186 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2187 	if (ipv6_addr_any(&addr))
2188 		return;
2189 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2190 }
2191 
2192 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2193 {
2194 	switch (dev->addr_len) {
2195 	case ETH_ALEN:
2196 		memcpy(eui, dev->dev_addr, 3);
2197 		eui[3] = 0xFF;
2198 		eui[4] = 0xFE;
2199 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2200 		break;
2201 	case EUI64_ADDR_LEN:
2202 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2203 		eui[0] ^= 2;
2204 		break;
2205 	default:
2206 		return -1;
2207 	}
2208 
2209 	return 0;
2210 }
2211 
2212 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2213 {
2214 	union fwnet_hwaddr *ha;
2215 
2216 	if (dev->addr_len != FWNET_ALEN)
2217 		return -1;
2218 
2219 	ha = (union fwnet_hwaddr *)dev->dev_addr;
2220 
2221 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2222 	eui[0] ^= 2;
2223 	return 0;
2224 }
2225 
2226 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2227 {
2228 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2229 	if (dev->addr_len != ARCNET_ALEN)
2230 		return -1;
2231 	memset(eui, 0, 7);
2232 	eui[7] = *(u8 *)dev->dev_addr;
2233 	return 0;
2234 }
2235 
2236 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2237 {
2238 	if (dev->addr_len != INFINIBAND_ALEN)
2239 		return -1;
2240 	memcpy(eui, dev->dev_addr + 12, 8);
2241 	eui[0] |= 2;
2242 	return 0;
2243 }
2244 
2245 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2246 {
2247 	if (addr == 0)
2248 		return -1;
2249 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2250 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2251 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2252 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2253 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2254 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2255 	eui[1] = 0;
2256 	eui[2] = 0x5E;
2257 	eui[3] = 0xFE;
2258 	memcpy(eui + 4, &addr, 4);
2259 	return 0;
2260 }
2261 
2262 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2263 {
2264 	if (dev->priv_flags & IFF_ISATAP)
2265 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2266 	return -1;
2267 }
2268 
2269 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2270 {
2271 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2272 }
2273 
2274 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2275 {
2276 	memcpy(eui, dev->perm_addr, 3);
2277 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2278 	eui[3] = 0xFF;
2279 	eui[4] = 0xFE;
2280 	eui[0] ^= 2;
2281 	return 0;
2282 }
2283 
2284 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2285 {
2286 	switch (dev->type) {
2287 	case ARPHRD_ETHER:
2288 	case ARPHRD_FDDI:
2289 		return addrconf_ifid_eui48(eui, dev);
2290 	case ARPHRD_ARCNET:
2291 		return addrconf_ifid_arcnet(eui, dev);
2292 	case ARPHRD_INFINIBAND:
2293 		return addrconf_ifid_infiniband(eui, dev);
2294 	case ARPHRD_SIT:
2295 		return addrconf_ifid_sit(eui, dev);
2296 	case ARPHRD_IPGRE:
2297 	case ARPHRD_TUNNEL:
2298 		return addrconf_ifid_gre(eui, dev);
2299 	case ARPHRD_6LOWPAN:
2300 		return addrconf_ifid_6lowpan(eui, dev);
2301 	case ARPHRD_IEEE1394:
2302 		return addrconf_ifid_ieee1394(eui, dev);
2303 	case ARPHRD_TUNNEL6:
2304 	case ARPHRD_IP6GRE:
2305 	case ARPHRD_RAWIP:
2306 		return addrconf_ifid_ip6tnl(eui, dev);
2307 	}
2308 	return -1;
2309 }
2310 
2311 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2312 {
2313 	int err = -1;
2314 	struct inet6_ifaddr *ifp;
2315 
2316 	read_lock_bh(&idev->lock);
2317 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2318 		if (ifp->scope > IFA_LINK)
2319 			break;
2320 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2321 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2322 			err = 0;
2323 			break;
2324 		}
2325 	}
2326 	read_unlock_bh(&idev->lock);
2327 	return err;
2328 }
2329 
2330 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
2331 static void ipv6_regen_rndid(struct inet6_dev *idev)
2332 {
2333 regen:
2334 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
2335 	idev->rndid[0] &= ~0x02;
2336 
2337 	/*
2338 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
2339 	 * check if generated address is not inappropriate
2340 	 *
2341 	 *  - Reserved subnet anycast (RFC 2526)
2342 	 *	11111101 11....11 1xxxxxxx
2343 	 *  - ISATAP (RFC4214) 6.1
2344 	 *	00-00-5E-FE-xx-xx-xx-xx
2345 	 *  - value 0
2346 	 *  - XXX: already assigned to an address on the device
2347 	 */
2348 	if (idev->rndid[0] == 0xfd &&
2349 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
2350 	    (idev->rndid[7]&0x80))
2351 		goto regen;
2352 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
2353 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
2354 			goto regen;
2355 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
2356 			goto regen;
2357 	}
2358 }
2359 
2360 static void  ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
2361 {
2362 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
2363 		ipv6_regen_rndid(idev);
2364 }
2365 
2366 /*
2367  *	Add prefix route.
2368  */
2369 
2370 static void
2371 addrconf_prefix_route(struct in6_addr *pfx, int plen, u32 metric,
2372 		      struct net_device *dev, unsigned long expires,
2373 		      u32 flags, gfp_t gfp_flags)
2374 {
2375 	struct fib6_config cfg = {
2376 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2377 		.fc_metric = metric ? : IP6_RT_PRIO_ADDRCONF,
2378 		.fc_ifindex = dev->ifindex,
2379 		.fc_expires = expires,
2380 		.fc_dst_len = plen,
2381 		.fc_flags = RTF_UP | flags,
2382 		.fc_nlinfo.nl_net = dev_net(dev),
2383 		.fc_protocol = RTPROT_KERNEL,
2384 		.fc_type = RTN_UNICAST,
2385 	};
2386 
2387 	cfg.fc_dst = *pfx;
2388 
2389 	/* Prevent useless cloning on PtP SIT.
2390 	   This thing is done here expecting that the whole
2391 	   class of non-broadcast devices need not cloning.
2392 	 */
2393 #if IS_ENABLED(CONFIG_IPV6_SIT)
2394 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2395 		cfg.fc_flags |= RTF_NONEXTHOP;
2396 #endif
2397 
2398 	ip6_route_add(&cfg, gfp_flags, NULL);
2399 }
2400 
2401 
2402 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2403 						  int plen,
2404 						  const struct net_device *dev,
2405 						  u32 flags, u32 noflags,
2406 						  bool no_gw)
2407 {
2408 	struct fib6_node *fn;
2409 	struct fib6_info *rt = NULL;
2410 	struct fib6_table *table;
2411 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2412 
2413 	table = fib6_get_table(dev_net(dev), tb_id);
2414 	if (!table)
2415 		return NULL;
2416 
2417 	rcu_read_lock();
2418 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2419 	if (!fn)
2420 		goto out;
2421 
2422 	for_each_fib6_node_rt_rcu(fn) {
2423 		/* prefix routes only use builtin fib6_nh */
2424 		if (rt->nh)
2425 			continue;
2426 
2427 		if (rt->fib6_nh->fib_nh_dev->ifindex != dev->ifindex)
2428 			continue;
2429 		if (no_gw && rt->fib6_nh->fib_nh_gw_family)
2430 			continue;
2431 		if ((rt->fib6_flags & flags) != flags)
2432 			continue;
2433 		if ((rt->fib6_flags & noflags) != 0)
2434 			continue;
2435 		if (!fib6_info_hold_safe(rt))
2436 			continue;
2437 		break;
2438 	}
2439 out:
2440 	rcu_read_unlock();
2441 	return rt;
2442 }
2443 
2444 
2445 /* Create "default" multicast route to the interface */
2446 
2447 static void addrconf_add_mroute(struct net_device *dev)
2448 {
2449 	struct fib6_config cfg = {
2450 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2451 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2452 		.fc_ifindex = dev->ifindex,
2453 		.fc_dst_len = 8,
2454 		.fc_flags = RTF_UP,
2455 		.fc_type = RTN_UNICAST,
2456 		.fc_nlinfo.nl_net = dev_net(dev),
2457 	};
2458 
2459 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2460 
2461 	ip6_route_add(&cfg, GFP_KERNEL, NULL);
2462 }
2463 
2464 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2465 {
2466 	struct inet6_dev *idev;
2467 
2468 	ASSERT_RTNL();
2469 
2470 	idev = ipv6_find_idev(dev);
2471 	if (IS_ERR(idev))
2472 		return idev;
2473 
2474 	if (idev->cnf.disable_ipv6)
2475 		return ERR_PTR(-EACCES);
2476 
2477 	/* Add default multicast route */
2478 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2479 		addrconf_add_mroute(dev);
2480 
2481 	return idev;
2482 }
2483 
2484 static void manage_tempaddrs(struct inet6_dev *idev,
2485 			     struct inet6_ifaddr *ifp,
2486 			     __u32 valid_lft, __u32 prefered_lft,
2487 			     bool create, unsigned long now)
2488 {
2489 	u32 flags;
2490 	struct inet6_ifaddr *ift;
2491 
2492 	read_lock_bh(&idev->lock);
2493 	/* update all temporary addresses in the list */
2494 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2495 		int age, max_valid, max_prefered;
2496 
2497 		if (ifp != ift->ifpub)
2498 			continue;
2499 
2500 		/* RFC 4941 section 3.3:
2501 		 * If a received option will extend the lifetime of a public
2502 		 * address, the lifetimes of temporary addresses should
2503 		 * be extended, subject to the overall constraint that no
2504 		 * temporary addresses should ever remain "valid" or "preferred"
2505 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2506 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2507 		 */
2508 		age = (now - ift->cstamp) / HZ;
2509 		max_valid = idev->cnf.temp_valid_lft - age;
2510 		if (max_valid < 0)
2511 			max_valid = 0;
2512 
2513 		max_prefered = idev->cnf.temp_prefered_lft -
2514 			       idev->desync_factor - age;
2515 		if (max_prefered < 0)
2516 			max_prefered = 0;
2517 
2518 		if (valid_lft > max_valid)
2519 			valid_lft = max_valid;
2520 
2521 		if (prefered_lft > max_prefered)
2522 			prefered_lft = max_prefered;
2523 
2524 		spin_lock(&ift->lock);
2525 		flags = ift->flags;
2526 		ift->valid_lft = valid_lft;
2527 		ift->prefered_lft = prefered_lft;
2528 		ift->tstamp = now;
2529 		if (prefered_lft > 0)
2530 			ift->flags &= ~IFA_F_DEPRECATED;
2531 
2532 		spin_unlock(&ift->lock);
2533 		if (!(flags&IFA_F_TENTATIVE))
2534 			ipv6_ifa_notify(0, ift);
2535 	}
2536 
2537 	if ((create || list_empty(&idev->tempaddr_list)) &&
2538 	    idev->cnf.use_tempaddr > 0) {
2539 		/* When a new public address is created as described
2540 		 * in [ADDRCONF], also create a new temporary address.
2541 		 * Also create a temporary address if it's enabled but
2542 		 * no temporary address currently exists.
2543 		 */
2544 		read_unlock_bh(&idev->lock);
2545 		ipv6_create_tempaddr(ifp, NULL, false);
2546 	} else {
2547 		read_unlock_bh(&idev->lock);
2548 	}
2549 }
2550 
2551 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2552 {
2553 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2554 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2555 }
2556 
2557 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2558 				 const struct prefix_info *pinfo,
2559 				 struct inet6_dev *in6_dev,
2560 				 const struct in6_addr *addr, int addr_type,
2561 				 u32 addr_flags, bool sllao, bool tokenized,
2562 				 __u32 valid_lft, u32 prefered_lft)
2563 {
2564 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2565 	int create = 0, update_lft = 0;
2566 
2567 	if (!ifp && valid_lft) {
2568 		int max_addresses = in6_dev->cnf.max_addresses;
2569 		struct ifa6_config cfg = {
2570 			.pfx = addr,
2571 			.plen = pinfo->prefix_len,
2572 			.ifa_flags = addr_flags,
2573 			.valid_lft = valid_lft,
2574 			.preferred_lft = prefered_lft,
2575 			.scope = addr_type & IPV6_ADDR_SCOPE_MASK,
2576 		};
2577 
2578 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2579 		if ((net->ipv6.devconf_all->optimistic_dad ||
2580 		     in6_dev->cnf.optimistic_dad) &&
2581 		    !net->ipv6.devconf_all->forwarding && sllao)
2582 			cfg.ifa_flags |= IFA_F_OPTIMISTIC;
2583 #endif
2584 
2585 		/* Do not allow to create too much of autoconfigured
2586 		 * addresses; this would be too easy way to crash kernel.
2587 		 */
2588 		if (!max_addresses ||
2589 		    ipv6_count_addresses(in6_dev) < max_addresses)
2590 			ifp = ipv6_add_addr(in6_dev, &cfg, false, NULL);
2591 
2592 		if (IS_ERR_OR_NULL(ifp))
2593 			return -1;
2594 
2595 		create = 1;
2596 		spin_lock_bh(&ifp->lock);
2597 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2598 		ifp->cstamp = jiffies;
2599 		ifp->tokenized = tokenized;
2600 		spin_unlock_bh(&ifp->lock);
2601 		addrconf_dad_start(ifp);
2602 	}
2603 
2604 	if (ifp) {
2605 		u32 flags;
2606 		unsigned long now;
2607 		u32 stored_lft;
2608 
2609 		/* update lifetime (RFC2462 5.5.3 e) */
2610 		spin_lock_bh(&ifp->lock);
2611 		now = jiffies;
2612 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2613 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2614 		else
2615 			stored_lft = 0;
2616 		if (!create && stored_lft) {
2617 			const u32 minimum_lft = min_t(u32,
2618 				stored_lft, MIN_VALID_LIFETIME);
2619 			valid_lft = max(valid_lft, minimum_lft);
2620 
2621 			/* RFC4862 Section 5.5.3e:
2622 			 * "Note that the preferred lifetime of the
2623 			 *  corresponding address is always reset to
2624 			 *  the Preferred Lifetime in the received
2625 			 *  Prefix Information option, regardless of
2626 			 *  whether the valid lifetime is also reset or
2627 			 *  ignored."
2628 			 *
2629 			 * So we should always update prefered_lft here.
2630 			 */
2631 			update_lft = 1;
2632 		}
2633 
2634 		if (update_lft) {
2635 			ifp->valid_lft = valid_lft;
2636 			ifp->prefered_lft = prefered_lft;
2637 			ifp->tstamp = now;
2638 			flags = ifp->flags;
2639 			ifp->flags &= ~IFA_F_DEPRECATED;
2640 			spin_unlock_bh(&ifp->lock);
2641 
2642 			if (!(flags&IFA_F_TENTATIVE))
2643 				ipv6_ifa_notify(0, ifp);
2644 		} else
2645 			spin_unlock_bh(&ifp->lock);
2646 
2647 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2648 				 create, now);
2649 
2650 		in6_ifa_put(ifp);
2651 		addrconf_verify();
2652 	}
2653 
2654 	return 0;
2655 }
2656 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2657 
2658 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2659 {
2660 	struct prefix_info *pinfo;
2661 	__u32 valid_lft;
2662 	__u32 prefered_lft;
2663 	int addr_type, err;
2664 	u32 addr_flags = 0;
2665 	struct inet6_dev *in6_dev;
2666 	struct net *net = dev_net(dev);
2667 
2668 	pinfo = (struct prefix_info *) opt;
2669 
2670 	if (len < sizeof(struct prefix_info)) {
2671 		netdev_dbg(dev, "addrconf: prefix option too short\n");
2672 		return;
2673 	}
2674 
2675 	/*
2676 	 *	Validation checks ([ADDRCONF], page 19)
2677 	 */
2678 
2679 	addr_type = ipv6_addr_type(&pinfo->prefix);
2680 
2681 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2682 		return;
2683 
2684 	valid_lft = ntohl(pinfo->valid);
2685 	prefered_lft = ntohl(pinfo->prefered);
2686 
2687 	if (prefered_lft > valid_lft) {
2688 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2689 		return;
2690 	}
2691 
2692 	in6_dev = in6_dev_get(dev);
2693 
2694 	if (!in6_dev) {
2695 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2696 				    dev->name);
2697 		return;
2698 	}
2699 
2700 	/*
2701 	 *	Two things going on here:
2702 	 *	1) Add routes for on-link prefixes
2703 	 *	2) Configure prefixes with the auto flag set
2704 	 */
2705 
2706 	if (pinfo->onlink) {
2707 		struct fib6_info *rt;
2708 		unsigned long rt_expires;
2709 
2710 		/* Avoid arithmetic overflow. Really, we could
2711 		 * save rt_expires in seconds, likely valid_lft,
2712 		 * but it would require division in fib gc, that it
2713 		 * not good.
2714 		 */
2715 		if (HZ > USER_HZ)
2716 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2717 		else
2718 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2719 
2720 		if (addrconf_finite_timeout(rt_expires))
2721 			rt_expires *= HZ;
2722 
2723 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2724 					       pinfo->prefix_len,
2725 					       dev,
2726 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2727 					       RTF_DEFAULT, true);
2728 
2729 		if (rt) {
2730 			/* Autoconf prefix route */
2731 			if (valid_lft == 0) {
2732 				ip6_del_rt(net, rt);
2733 				rt = NULL;
2734 			} else if (addrconf_finite_timeout(rt_expires)) {
2735 				/* not infinity */
2736 				fib6_set_expires(rt, jiffies + rt_expires);
2737 			} else {
2738 				fib6_clean_expires(rt);
2739 			}
2740 		} else if (valid_lft) {
2741 			clock_t expires = 0;
2742 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2743 			if (addrconf_finite_timeout(rt_expires)) {
2744 				/* not infinity */
2745 				flags |= RTF_EXPIRES;
2746 				expires = jiffies_to_clock_t(rt_expires);
2747 			}
2748 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2749 					      0, dev, expires, flags,
2750 					      GFP_ATOMIC);
2751 		}
2752 		fib6_info_release(rt);
2753 	}
2754 
2755 	/* Try to figure out our local address for this prefix */
2756 
2757 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2758 		struct in6_addr addr;
2759 		bool tokenized = false, dev_addr_generated = false;
2760 
2761 		if (pinfo->prefix_len == 64) {
2762 			memcpy(&addr, &pinfo->prefix, 8);
2763 
2764 			if (!ipv6_addr_any(&in6_dev->token)) {
2765 				read_lock_bh(&in6_dev->lock);
2766 				memcpy(addr.s6_addr + 8,
2767 				       in6_dev->token.s6_addr + 8, 8);
2768 				read_unlock_bh(&in6_dev->lock);
2769 				tokenized = true;
2770 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2771 				   !ipv6_generate_stable_address(&addr, 0,
2772 								 in6_dev)) {
2773 				addr_flags |= IFA_F_STABLE_PRIVACY;
2774 				goto ok;
2775 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2776 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2777 				goto put;
2778 			} else {
2779 				dev_addr_generated = true;
2780 			}
2781 			goto ok;
2782 		}
2783 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2784 				    pinfo->prefix_len);
2785 		goto put;
2786 
2787 ok:
2788 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2789 						   &addr, addr_type,
2790 						   addr_flags, sllao,
2791 						   tokenized, valid_lft,
2792 						   prefered_lft);
2793 		if (err)
2794 			goto put;
2795 
2796 		/* Ignore error case here because previous prefix add addr was
2797 		 * successful which will be notified.
2798 		 */
2799 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2800 					      addr_type, addr_flags, sllao,
2801 					      tokenized, valid_lft,
2802 					      prefered_lft,
2803 					      dev_addr_generated);
2804 	}
2805 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2806 put:
2807 	in6_dev_put(in6_dev);
2808 }
2809 
2810 /*
2811  *	Set destination address.
2812  *	Special case for SIT interfaces where we create a new "virtual"
2813  *	device.
2814  */
2815 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2816 {
2817 	struct in6_ifreq ireq;
2818 	struct net_device *dev;
2819 	int err = -EINVAL;
2820 
2821 	rtnl_lock();
2822 
2823 	err = -EFAULT;
2824 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2825 		goto err_exit;
2826 
2827 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2828 
2829 	err = -ENODEV;
2830 	if (!dev)
2831 		goto err_exit;
2832 
2833 #if IS_ENABLED(CONFIG_IPV6_SIT)
2834 	if (dev->type == ARPHRD_SIT) {
2835 		const struct net_device_ops *ops = dev->netdev_ops;
2836 		struct ifreq ifr;
2837 		struct ip_tunnel_parm p;
2838 
2839 		err = -EADDRNOTAVAIL;
2840 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2841 			goto err_exit;
2842 
2843 		memset(&p, 0, sizeof(p));
2844 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2845 		p.iph.saddr = 0;
2846 		p.iph.version = 4;
2847 		p.iph.ihl = 5;
2848 		p.iph.protocol = IPPROTO_IPV6;
2849 		p.iph.ttl = 64;
2850 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2851 
2852 		if (ops->ndo_do_ioctl) {
2853 			mm_segment_t oldfs = get_fs();
2854 
2855 			set_fs(KERNEL_DS);
2856 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2857 			set_fs(oldfs);
2858 		} else
2859 			err = -EOPNOTSUPP;
2860 
2861 		if (err == 0) {
2862 			err = -ENOBUFS;
2863 			dev = __dev_get_by_name(net, p.name);
2864 			if (!dev)
2865 				goto err_exit;
2866 			err = dev_open(dev, NULL);
2867 		}
2868 	}
2869 #endif
2870 
2871 err_exit:
2872 	rtnl_unlock();
2873 	return err;
2874 }
2875 
2876 static int ipv6_mc_config(struct sock *sk, bool join,
2877 			  const struct in6_addr *addr, int ifindex)
2878 {
2879 	int ret;
2880 
2881 	ASSERT_RTNL();
2882 
2883 	lock_sock(sk);
2884 	if (join)
2885 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2886 	else
2887 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2888 	release_sock(sk);
2889 
2890 	return ret;
2891 }
2892 
2893 /*
2894  *	Manual configuration of address on an interface
2895  */
2896 static int inet6_addr_add(struct net *net, int ifindex,
2897 			  struct ifa6_config *cfg,
2898 			  struct netlink_ext_ack *extack)
2899 {
2900 	struct inet6_ifaddr *ifp;
2901 	struct inet6_dev *idev;
2902 	struct net_device *dev;
2903 	unsigned long timeout;
2904 	clock_t expires;
2905 	u32 flags;
2906 
2907 	ASSERT_RTNL();
2908 
2909 	if (cfg->plen > 128)
2910 		return -EINVAL;
2911 
2912 	/* check the lifetime */
2913 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
2914 		return -EINVAL;
2915 
2916 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR && cfg->plen != 64)
2917 		return -EINVAL;
2918 
2919 	dev = __dev_get_by_index(net, ifindex);
2920 	if (!dev)
2921 		return -ENODEV;
2922 
2923 	idev = addrconf_add_dev(dev);
2924 	if (IS_ERR(idev))
2925 		return PTR_ERR(idev);
2926 
2927 	if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2928 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2929 					 true, cfg->pfx, ifindex);
2930 
2931 		if (ret < 0)
2932 			return ret;
2933 	}
2934 
2935 	cfg->scope = ipv6_addr_scope(cfg->pfx);
2936 
2937 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
2938 	if (addrconf_finite_timeout(timeout)) {
2939 		expires = jiffies_to_clock_t(timeout * HZ);
2940 		cfg->valid_lft = timeout;
2941 		flags = RTF_EXPIRES;
2942 	} else {
2943 		expires = 0;
2944 		flags = 0;
2945 		cfg->ifa_flags |= IFA_F_PERMANENT;
2946 	}
2947 
2948 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
2949 	if (addrconf_finite_timeout(timeout)) {
2950 		if (timeout == 0)
2951 			cfg->ifa_flags |= IFA_F_DEPRECATED;
2952 		cfg->preferred_lft = timeout;
2953 	}
2954 
2955 	ifp = ipv6_add_addr(idev, cfg, true, extack);
2956 	if (!IS_ERR(ifp)) {
2957 		if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
2958 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
2959 					      ifp->rt_priority, dev, expires,
2960 					      flags, GFP_KERNEL);
2961 		}
2962 
2963 		/* Send a netlink notification if DAD is enabled and
2964 		 * optimistic flag is not set
2965 		 */
2966 		if (!(ifp->flags & (IFA_F_OPTIMISTIC | IFA_F_NODAD)))
2967 			ipv6_ifa_notify(0, ifp);
2968 		/*
2969 		 * Note that section 3.1 of RFC 4429 indicates
2970 		 * that the Optimistic flag should not be set for
2971 		 * manually configured addresses
2972 		 */
2973 		addrconf_dad_start(ifp);
2974 		if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR)
2975 			manage_tempaddrs(idev, ifp, cfg->valid_lft,
2976 					 cfg->preferred_lft, true, jiffies);
2977 		in6_ifa_put(ifp);
2978 		addrconf_verify_rtnl();
2979 		return 0;
2980 	} else if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2981 		ipv6_mc_config(net->ipv6.mc_autojoin_sk, false,
2982 			       cfg->pfx, ifindex);
2983 	}
2984 
2985 	return PTR_ERR(ifp);
2986 }
2987 
2988 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
2989 			  const struct in6_addr *pfx, unsigned int plen)
2990 {
2991 	struct inet6_ifaddr *ifp;
2992 	struct inet6_dev *idev;
2993 	struct net_device *dev;
2994 
2995 	if (plen > 128)
2996 		return -EINVAL;
2997 
2998 	dev = __dev_get_by_index(net, ifindex);
2999 	if (!dev)
3000 		return -ENODEV;
3001 
3002 	idev = __in6_dev_get(dev);
3003 	if (!idev)
3004 		return -ENXIO;
3005 
3006 	read_lock_bh(&idev->lock);
3007 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3008 		if (ifp->prefix_len == plen &&
3009 		    ipv6_addr_equal(pfx, &ifp->addr)) {
3010 			in6_ifa_hold(ifp);
3011 			read_unlock_bh(&idev->lock);
3012 
3013 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
3014 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
3015 				manage_tempaddrs(idev, ifp, 0, 0, false,
3016 						 jiffies);
3017 			ipv6_del_addr(ifp);
3018 			addrconf_verify_rtnl();
3019 			if (ipv6_addr_is_multicast(pfx)) {
3020 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3021 					       false, pfx, dev->ifindex);
3022 			}
3023 			return 0;
3024 		}
3025 	}
3026 	read_unlock_bh(&idev->lock);
3027 	return -EADDRNOTAVAIL;
3028 }
3029 
3030 
3031 int addrconf_add_ifaddr(struct net *net, void __user *arg)
3032 {
3033 	struct ifa6_config cfg = {
3034 		.ifa_flags = IFA_F_PERMANENT,
3035 		.preferred_lft = INFINITY_LIFE_TIME,
3036 		.valid_lft = INFINITY_LIFE_TIME,
3037 	};
3038 	struct in6_ifreq ireq;
3039 	int err;
3040 
3041 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3042 		return -EPERM;
3043 
3044 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3045 		return -EFAULT;
3046 
3047 	cfg.pfx = &ireq.ifr6_addr;
3048 	cfg.plen = ireq.ifr6_prefixlen;
3049 
3050 	rtnl_lock();
3051 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &cfg, NULL);
3052 	rtnl_unlock();
3053 	return err;
3054 }
3055 
3056 int addrconf_del_ifaddr(struct net *net, void __user *arg)
3057 {
3058 	struct in6_ifreq ireq;
3059 	int err;
3060 
3061 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3062 		return -EPERM;
3063 
3064 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3065 		return -EFAULT;
3066 
3067 	rtnl_lock();
3068 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
3069 			     ireq.ifr6_prefixlen);
3070 	rtnl_unlock();
3071 	return err;
3072 }
3073 
3074 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
3075 		     int plen, int scope)
3076 {
3077 	struct inet6_ifaddr *ifp;
3078 	struct ifa6_config cfg = {
3079 		.pfx = addr,
3080 		.plen = plen,
3081 		.ifa_flags = IFA_F_PERMANENT,
3082 		.valid_lft = INFINITY_LIFE_TIME,
3083 		.preferred_lft = INFINITY_LIFE_TIME,
3084 		.scope = scope
3085 	};
3086 
3087 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3088 	if (!IS_ERR(ifp)) {
3089 		spin_lock_bh(&ifp->lock);
3090 		ifp->flags &= ~IFA_F_TENTATIVE;
3091 		spin_unlock_bh(&ifp->lock);
3092 		rt_genid_bump_ipv6(dev_net(idev->dev));
3093 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3094 		in6_ifa_put(ifp);
3095 	}
3096 }
3097 
3098 #if IS_ENABLED(CONFIG_IPV6_SIT)
3099 static void sit_add_v4_addrs(struct inet6_dev *idev)
3100 {
3101 	struct in6_addr addr;
3102 	struct net_device *dev;
3103 	struct net *net = dev_net(idev->dev);
3104 	int scope, plen;
3105 	u32 pflags = 0;
3106 
3107 	ASSERT_RTNL();
3108 
3109 	memset(&addr, 0, sizeof(struct in6_addr));
3110 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
3111 
3112 	if (idev->dev->flags&IFF_POINTOPOINT) {
3113 		addr.s6_addr32[0] = htonl(0xfe800000);
3114 		scope = IFA_LINK;
3115 		plen = 64;
3116 	} else {
3117 		scope = IPV6_ADDR_COMPATv4;
3118 		plen = 96;
3119 		pflags |= RTF_NONEXTHOP;
3120 	}
3121 
3122 	if (addr.s6_addr32[3]) {
3123 		add_addr(idev, &addr, plen, scope);
3124 		addrconf_prefix_route(&addr, plen, 0, idev->dev, 0, pflags,
3125 				      GFP_KERNEL);
3126 		return;
3127 	}
3128 
3129 	for_each_netdev(net, dev) {
3130 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3131 		if (in_dev && (dev->flags & IFF_UP)) {
3132 			struct in_ifaddr *ifa;
3133 			int flag = scope;
3134 
3135 			in_dev_for_each_ifa_rtnl(ifa, in_dev) {
3136 				addr.s6_addr32[3] = ifa->ifa_local;
3137 
3138 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3139 					continue;
3140 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3141 					if (idev->dev->flags&IFF_POINTOPOINT)
3142 						continue;
3143 					flag |= IFA_HOST;
3144 				}
3145 
3146 				add_addr(idev, &addr, plen, flag);
3147 				addrconf_prefix_route(&addr, plen, 0, idev->dev,
3148 						      0, pflags, GFP_KERNEL);
3149 			}
3150 		}
3151 	}
3152 }
3153 #endif
3154 
3155 static void init_loopback(struct net_device *dev)
3156 {
3157 	struct inet6_dev  *idev;
3158 
3159 	/* ::1 */
3160 
3161 	ASSERT_RTNL();
3162 
3163 	idev = ipv6_find_idev(dev);
3164 	if (IS_ERR(idev)) {
3165 		pr_debug("%s: add_dev failed\n", __func__);
3166 		return;
3167 	}
3168 
3169 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
3170 }
3171 
3172 void addrconf_add_linklocal(struct inet6_dev *idev,
3173 			    const struct in6_addr *addr, u32 flags)
3174 {
3175 	struct ifa6_config cfg = {
3176 		.pfx = addr,
3177 		.plen = 64,
3178 		.ifa_flags = flags | IFA_F_PERMANENT,
3179 		.valid_lft = INFINITY_LIFE_TIME,
3180 		.preferred_lft = INFINITY_LIFE_TIME,
3181 		.scope = IFA_LINK
3182 	};
3183 	struct inet6_ifaddr *ifp;
3184 
3185 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3186 	if ((dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad ||
3187 	     idev->cnf.optimistic_dad) &&
3188 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3189 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
3190 #endif
3191 
3192 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3193 	if (!IS_ERR(ifp)) {
3194 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, 0, idev->dev,
3195 				      0, 0, GFP_ATOMIC);
3196 		addrconf_dad_start(ifp);
3197 		in6_ifa_put(ifp);
3198 	}
3199 }
3200 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3201 
3202 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3203 {
3204 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3205 		return true;
3206 
3207 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3208 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3209 		return true;
3210 
3211 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3212 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3213 		return true;
3214 
3215 	return false;
3216 }
3217 
3218 static int ipv6_generate_stable_address(struct in6_addr *address,
3219 					u8 dad_count,
3220 					const struct inet6_dev *idev)
3221 {
3222 	static DEFINE_SPINLOCK(lock);
3223 	static __u32 digest[SHA_DIGEST_WORDS];
3224 	static __u32 workspace[SHA_WORKSPACE_WORDS];
3225 
3226 	static union {
3227 		char __data[SHA_MESSAGE_BYTES];
3228 		struct {
3229 			struct in6_addr secret;
3230 			__be32 prefix[2];
3231 			unsigned char hwaddr[MAX_ADDR_LEN];
3232 			u8 dad_count;
3233 		} __packed;
3234 	} data;
3235 
3236 	struct in6_addr secret;
3237 	struct in6_addr temp;
3238 	struct net *net = dev_net(idev->dev);
3239 
3240 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3241 
3242 	if (idev->cnf.stable_secret.initialized)
3243 		secret = idev->cnf.stable_secret.secret;
3244 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3245 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3246 	else
3247 		return -1;
3248 
3249 retry:
3250 	spin_lock_bh(&lock);
3251 
3252 	sha_init(digest);
3253 	memset(&data, 0, sizeof(data));
3254 	memset(workspace, 0, sizeof(workspace));
3255 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3256 	data.prefix[0] = address->s6_addr32[0];
3257 	data.prefix[1] = address->s6_addr32[1];
3258 	data.secret = secret;
3259 	data.dad_count = dad_count;
3260 
3261 	sha_transform(digest, data.__data, workspace);
3262 
3263 	temp = *address;
3264 	temp.s6_addr32[2] = (__force __be32)digest[0];
3265 	temp.s6_addr32[3] = (__force __be32)digest[1];
3266 
3267 	spin_unlock_bh(&lock);
3268 
3269 	if (ipv6_reserved_interfaceid(temp)) {
3270 		dad_count++;
3271 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3272 			return -1;
3273 		goto retry;
3274 	}
3275 
3276 	*address = temp;
3277 	return 0;
3278 }
3279 
3280 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3281 {
3282 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3283 
3284 	if (s->initialized)
3285 		return;
3286 	s = &idev->cnf.stable_secret;
3287 	get_random_bytes(&s->secret, sizeof(s->secret));
3288 	s->initialized = true;
3289 }
3290 
3291 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3292 {
3293 	struct in6_addr addr;
3294 
3295 	/* no link local addresses on L3 master devices */
3296 	if (netif_is_l3_master(idev->dev))
3297 		return;
3298 
3299 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3300 
3301 	switch (idev->cnf.addr_gen_mode) {
3302 	case IN6_ADDR_GEN_MODE_RANDOM:
3303 		ipv6_gen_mode_random_init(idev);
3304 		/* fallthrough */
3305 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3306 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3307 			addrconf_add_linklocal(idev, &addr,
3308 					       IFA_F_STABLE_PRIVACY);
3309 		else if (prefix_route)
3310 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3311 					      0, 0, GFP_KERNEL);
3312 		break;
3313 	case IN6_ADDR_GEN_MODE_EUI64:
3314 		/* addrconf_add_linklocal also adds a prefix_route and we
3315 		 * only need to care about prefix routes if ipv6_generate_eui64
3316 		 * couldn't generate one.
3317 		 */
3318 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3319 			addrconf_add_linklocal(idev, &addr, 0);
3320 		else if (prefix_route)
3321 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3322 					      0, 0, GFP_KERNEL);
3323 		break;
3324 	case IN6_ADDR_GEN_MODE_NONE:
3325 	default:
3326 		/* will not add any link local address */
3327 		break;
3328 	}
3329 }
3330 
3331 static void addrconf_dev_config(struct net_device *dev)
3332 {
3333 	struct inet6_dev *idev;
3334 
3335 	ASSERT_RTNL();
3336 
3337 	if ((dev->type != ARPHRD_ETHER) &&
3338 	    (dev->type != ARPHRD_FDDI) &&
3339 	    (dev->type != ARPHRD_ARCNET) &&
3340 	    (dev->type != ARPHRD_INFINIBAND) &&
3341 	    (dev->type != ARPHRD_IEEE1394) &&
3342 	    (dev->type != ARPHRD_TUNNEL6) &&
3343 	    (dev->type != ARPHRD_6LOWPAN) &&
3344 	    (dev->type != ARPHRD_IP6GRE) &&
3345 	    (dev->type != ARPHRD_IPGRE) &&
3346 	    (dev->type != ARPHRD_TUNNEL) &&
3347 	    (dev->type != ARPHRD_NONE) &&
3348 	    (dev->type != ARPHRD_RAWIP)) {
3349 		/* Alas, we support only Ethernet autoconfiguration. */
3350 		idev = __in6_dev_get(dev);
3351 		if (!IS_ERR_OR_NULL(idev) && dev->flags & IFF_UP &&
3352 		    dev->flags & IFF_MULTICAST)
3353 			ipv6_mc_up(idev);
3354 		return;
3355 	}
3356 
3357 	idev = addrconf_add_dev(dev);
3358 	if (IS_ERR(idev))
3359 		return;
3360 
3361 	/* this device type has no EUI support */
3362 	if (dev->type == ARPHRD_NONE &&
3363 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3364 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_RANDOM;
3365 
3366 	addrconf_addr_gen(idev, false);
3367 }
3368 
3369 #if IS_ENABLED(CONFIG_IPV6_SIT)
3370 static void addrconf_sit_config(struct net_device *dev)
3371 {
3372 	struct inet6_dev *idev;
3373 
3374 	ASSERT_RTNL();
3375 
3376 	/*
3377 	 * Configure the tunnel with one of our IPv4
3378 	 * addresses... we should configure all of
3379 	 * our v4 addrs in the tunnel
3380 	 */
3381 
3382 	idev = ipv6_find_idev(dev);
3383 	if (IS_ERR(idev)) {
3384 		pr_debug("%s: add_dev failed\n", __func__);
3385 		return;
3386 	}
3387 
3388 	if (dev->priv_flags & IFF_ISATAP) {
3389 		addrconf_addr_gen(idev, false);
3390 		return;
3391 	}
3392 
3393 	sit_add_v4_addrs(idev);
3394 
3395 	if (dev->flags&IFF_POINTOPOINT)
3396 		addrconf_add_mroute(dev);
3397 }
3398 #endif
3399 
3400 #if IS_ENABLED(CONFIG_NET_IPGRE)
3401 static void addrconf_gre_config(struct net_device *dev)
3402 {
3403 	struct inet6_dev *idev;
3404 
3405 	ASSERT_RTNL();
3406 
3407 	idev = ipv6_find_idev(dev);
3408 	if (IS_ERR(idev)) {
3409 		pr_debug("%s: add_dev failed\n", __func__);
3410 		return;
3411 	}
3412 
3413 	addrconf_addr_gen(idev, true);
3414 	if (dev->flags & IFF_POINTOPOINT)
3415 		addrconf_add_mroute(dev);
3416 }
3417 #endif
3418 
3419 static int fixup_permanent_addr(struct net *net,
3420 				struct inet6_dev *idev,
3421 				struct inet6_ifaddr *ifp)
3422 {
3423 	/* !fib6_node means the host route was removed from the
3424 	 * FIB, for example, if 'lo' device is taken down. In that
3425 	 * case regenerate the host route.
3426 	 */
3427 	if (!ifp->rt || !ifp->rt->fib6_node) {
3428 		struct fib6_info *f6i, *prev;
3429 
3430 		f6i = addrconf_f6i_alloc(net, idev, &ifp->addr, false,
3431 					 GFP_ATOMIC);
3432 		if (IS_ERR(f6i))
3433 			return PTR_ERR(f6i);
3434 
3435 		/* ifp->rt can be accessed outside of rtnl */
3436 		spin_lock(&ifp->lock);
3437 		prev = ifp->rt;
3438 		ifp->rt = f6i;
3439 		spin_unlock(&ifp->lock);
3440 
3441 		fib6_info_release(prev);
3442 	}
3443 
3444 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3445 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3446 				      ifp->rt_priority, idev->dev, 0, 0,
3447 				      GFP_ATOMIC);
3448 	}
3449 
3450 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3451 		addrconf_dad_start(ifp);
3452 
3453 	return 0;
3454 }
3455 
3456 static void addrconf_permanent_addr(struct net *net, struct net_device *dev)
3457 {
3458 	struct inet6_ifaddr *ifp, *tmp;
3459 	struct inet6_dev *idev;
3460 
3461 	idev = __in6_dev_get(dev);
3462 	if (!idev)
3463 		return;
3464 
3465 	write_lock_bh(&idev->lock);
3466 
3467 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3468 		if ((ifp->flags & IFA_F_PERMANENT) &&
3469 		    fixup_permanent_addr(net, idev, ifp) < 0) {
3470 			write_unlock_bh(&idev->lock);
3471 			in6_ifa_hold(ifp);
3472 			ipv6_del_addr(ifp);
3473 			write_lock_bh(&idev->lock);
3474 
3475 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3476 					     idev->dev->name, &ifp->addr);
3477 		}
3478 	}
3479 
3480 	write_unlock_bh(&idev->lock);
3481 }
3482 
3483 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3484 			   void *ptr)
3485 {
3486 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3487 	struct netdev_notifier_change_info *change_info;
3488 	struct netdev_notifier_changeupper_info *info;
3489 	struct inet6_dev *idev = __in6_dev_get(dev);
3490 	struct net *net = dev_net(dev);
3491 	int run_pending = 0;
3492 	int err;
3493 
3494 	switch (event) {
3495 	case NETDEV_REGISTER:
3496 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3497 			idev = ipv6_add_dev(dev);
3498 			if (IS_ERR(idev))
3499 				return notifier_from_errno(PTR_ERR(idev));
3500 		}
3501 		break;
3502 
3503 	case NETDEV_CHANGEMTU:
3504 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3505 		if (dev->mtu < IPV6_MIN_MTU) {
3506 			addrconf_ifdown(dev, dev != net->loopback_dev);
3507 			break;
3508 		}
3509 
3510 		if (idev) {
3511 			rt6_mtu_change(dev, dev->mtu);
3512 			idev->cnf.mtu6 = dev->mtu;
3513 			break;
3514 		}
3515 
3516 		/* allocate new idev */
3517 		idev = ipv6_add_dev(dev);
3518 		if (IS_ERR(idev))
3519 			break;
3520 
3521 		/* device is still not ready */
3522 		if (!(idev->if_flags & IF_READY))
3523 			break;
3524 
3525 		run_pending = 1;
3526 
3527 		/* fall through */
3528 
3529 	case NETDEV_UP:
3530 	case NETDEV_CHANGE:
3531 		if (dev->flags & IFF_SLAVE)
3532 			break;
3533 
3534 		if (idev && idev->cnf.disable_ipv6)
3535 			break;
3536 
3537 		if (event == NETDEV_UP) {
3538 			/* restore routes for permanent addresses */
3539 			addrconf_permanent_addr(net, dev);
3540 
3541 			if (!addrconf_link_ready(dev)) {
3542 				/* device is not ready yet. */
3543 				pr_debug("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3544 					 dev->name);
3545 				break;
3546 			}
3547 
3548 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3549 				idev = ipv6_add_dev(dev);
3550 
3551 			if (!IS_ERR_OR_NULL(idev)) {
3552 				idev->if_flags |= IF_READY;
3553 				run_pending = 1;
3554 			}
3555 		} else if (event == NETDEV_CHANGE) {
3556 			if (!addrconf_link_ready(dev)) {
3557 				/* device is still not ready. */
3558 				rt6_sync_down_dev(dev, event);
3559 				break;
3560 			}
3561 
3562 			if (!IS_ERR_OR_NULL(idev)) {
3563 				if (idev->if_flags & IF_READY) {
3564 					/* device is already configured -
3565 					 * but resend MLD reports, we might
3566 					 * have roamed and need to update
3567 					 * multicast snooping switches
3568 					 */
3569 					ipv6_mc_up(idev);
3570 					change_info = ptr;
3571 					if (change_info->flags_changed & IFF_NOARP)
3572 						addrconf_dad_run(idev, true);
3573 					rt6_sync_up(dev, RTNH_F_LINKDOWN);
3574 					break;
3575 				}
3576 				idev->if_flags |= IF_READY;
3577 			}
3578 
3579 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3580 				dev->name);
3581 
3582 			run_pending = 1;
3583 		}
3584 
3585 		switch (dev->type) {
3586 #if IS_ENABLED(CONFIG_IPV6_SIT)
3587 		case ARPHRD_SIT:
3588 			addrconf_sit_config(dev);
3589 			break;
3590 #endif
3591 #if IS_ENABLED(CONFIG_NET_IPGRE)
3592 		case ARPHRD_IPGRE:
3593 			addrconf_gre_config(dev);
3594 			break;
3595 #endif
3596 		case ARPHRD_LOOPBACK:
3597 			init_loopback(dev);
3598 			break;
3599 
3600 		default:
3601 			addrconf_dev_config(dev);
3602 			break;
3603 		}
3604 
3605 		if (!IS_ERR_OR_NULL(idev)) {
3606 			if (run_pending)
3607 				addrconf_dad_run(idev, false);
3608 
3609 			/* Device has an address by now */
3610 			rt6_sync_up(dev, RTNH_F_DEAD);
3611 
3612 			/*
3613 			 * If the MTU changed during the interface down,
3614 			 * when the interface up, the changed MTU must be
3615 			 * reflected in the idev as well as routers.
3616 			 */
3617 			if (idev->cnf.mtu6 != dev->mtu &&
3618 			    dev->mtu >= IPV6_MIN_MTU) {
3619 				rt6_mtu_change(dev, dev->mtu);
3620 				idev->cnf.mtu6 = dev->mtu;
3621 			}
3622 			idev->tstamp = jiffies;
3623 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3624 
3625 			/*
3626 			 * If the changed mtu during down is lower than
3627 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3628 			 */
3629 			if (dev->mtu < IPV6_MIN_MTU)
3630 				addrconf_ifdown(dev, dev != net->loopback_dev);
3631 		}
3632 		break;
3633 
3634 	case NETDEV_DOWN:
3635 	case NETDEV_UNREGISTER:
3636 		/*
3637 		 *	Remove all addresses from this interface.
3638 		 */
3639 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3640 		break;
3641 
3642 	case NETDEV_CHANGENAME:
3643 		if (idev) {
3644 			snmp6_unregister_dev(idev);
3645 			addrconf_sysctl_unregister(idev);
3646 			err = addrconf_sysctl_register(idev);
3647 			if (err)
3648 				return notifier_from_errno(err);
3649 			err = snmp6_register_dev(idev);
3650 			if (err) {
3651 				addrconf_sysctl_unregister(idev);
3652 				return notifier_from_errno(err);
3653 			}
3654 		}
3655 		break;
3656 
3657 	case NETDEV_PRE_TYPE_CHANGE:
3658 	case NETDEV_POST_TYPE_CHANGE:
3659 		if (idev)
3660 			addrconf_type_change(dev, event);
3661 		break;
3662 
3663 	case NETDEV_CHANGEUPPER:
3664 		info = ptr;
3665 
3666 		/* flush all routes if dev is linked to or unlinked from
3667 		 * an L3 master device (e.g., VRF)
3668 		 */
3669 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3670 			addrconf_ifdown(dev, 0);
3671 	}
3672 
3673 	return NOTIFY_OK;
3674 }
3675 
3676 /*
3677  *	addrconf module should be notified of a device going up
3678  */
3679 static struct notifier_block ipv6_dev_notf = {
3680 	.notifier_call = addrconf_notify,
3681 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3682 };
3683 
3684 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3685 {
3686 	struct inet6_dev *idev;
3687 	ASSERT_RTNL();
3688 
3689 	idev = __in6_dev_get(dev);
3690 
3691 	if (event == NETDEV_POST_TYPE_CHANGE)
3692 		ipv6_mc_remap(idev);
3693 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3694 		ipv6_mc_unmap(idev);
3695 }
3696 
3697 static bool addr_is_local(const struct in6_addr *addr)
3698 {
3699 	return ipv6_addr_type(addr) &
3700 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3701 }
3702 
3703 static int addrconf_ifdown(struct net_device *dev, int how)
3704 {
3705 	unsigned long event = how ? NETDEV_UNREGISTER : NETDEV_DOWN;
3706 	struct net *net = dev_net(dev);
3707 	struct inet6_dev *idev;
3708 	struct inet6_ifaddr *ifa, *tmp;
3709 	bool keep_addr = false;
3710 	int state, i;
3711 
3712 	ASSERT_RTNL();
3713 
3714 	rt6_disable_ip(dev, event);
3715 
3716 	idev = __in6_dev_get(dev);
3717 	if (!idev)
3718 		return -ENODEV;
3719 
3720 	/*
3721 	 * Step 1: remove reference to ipv6 device from parent device.
3722 	 *	   Do not dev_put!
3723 	 */
3724 	if (how) {
3725 		idev->dead = 1;
3726 
3727 		/* protected by rtnl_lock */
3728 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3729 
3730 		/* Step 1.5: remove snmp6 entry */
3731 		snmp6_unregister_dev(idev);
3732 
3733 	}
3734 
3735 	/* combine the user config with event to determine if permanent
3736 	 * addresses are to be removed from address hash table
3737 	 */
3738 	if (!how && !idev->cnf.disable_ipv6) {
3739 		/* aggregate the system setting and interface setting */
3740 		int _keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
3741 
3742 		if (!_keep_addr)
3743 			_keep_addr = idev->cnf.keep_addr_on_down;
3744 
3745 		keep_addr = (_keep_addr > 0);
3746 	}
3747 
3748 	/* Step 2: clear hash table */
3749 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3750 		struct hlist_head *h = &inet6_addr_lst[i];
3751 
3752 		spin_lock_bh(&addrconf_hash_lock);
3753 restart:
3754 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3755 			if (ifa->idev == idev) {
3756 				addrconf_del_dad_work(ifa);
3757 				/* combined flag + permanent flag decide if
3758 				 * address is retained on a down event
3759 				 */
3760 				if (!keep_addr ||
3761 				    !(ifa->flags & IFA_F_PERMANENT) ||
3762 				    addr_is_local(&ifa->addr)) {
3763 					hlist_del_init_rcu(&ifa->addr_lst);
3764 					goto restart;
3765 				}
3766 			}
3767 		}
3768 		spin_unlock_bh(&addrconf_hash_lock);
3769 	}
3770 
3771 	write_lock_bh(&idev->lock);
3772 
3773 	addrconf_del_rs_timer(idev);
3774 
3775 	/* Step 2: clear flags for stateless addrconf */
3776 	if (!how)
3777 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3778 
3779 	/* Step 3: clear tempaddr list */
3780 	while (!list_empty(&idev->tempaddr_list)) {
3781 		ifa = list_first_entry(&idev->tempaddr_list,
3782 				       struct inet6_ifaddr, tmp_list);
3783 		list_del(&ifa->tmp_list);
3784 		write_unlock_bh(&idev->lock);
3785 		spin_lock_bh(&ifa->lock);
3786 
3787 		if (ifa->ifpub) {
3788 			in6_ifa_put(ifa->ifpub);
3789 			ifa->ifpub = NULL;
3790 		}
3791 		spin_unlock_bh(&ifa->lock);
3792 		in6_ifa_put(ifa);
3793 		write_lock_bh(&idev->lock);
3794 	}
3795 
3796 	list_for_each_entry_safe(ifa, tmp, &idev->addr_list, if_list) {
3797 		struct fib6_info *rt = NULL;
3798 		bool keep;
3799 
3800 		addrconf_del_dad_work(ifa);
3801 
3802 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3803 			!addr_is_local(&ifa->addr);
3804 
3805 		write_unlock_bh(&idev->lock);
3806 		spin_lock_bh(&ifa->lock);
3807 
3808 		if (keep) {
3809 			/* set state to skip the notifier below */
3810 			state = INET6_IFADDR_STATE_DEAD;
3811 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3812 			if (!(ifa->flags & IFA_F_NODAD))
3813 				ifa->flags |= IFA_F_TENTATIVE;
3814 
3815 			rt = ifa->rt;
3816 			ifa->rt = NULL;
3817 		} else {
3818 			state = ifa->state;
3819 			ifa->state = INET6_IFADDR_STATE_DEAD;
3820 		}
3821 
3822 		spin_unlock_bh(&ifa->lock);
3823 
3824 		if (rt)
3825 			ip6_del_rt(net, rt);
3826 
3827 		if (state != INET6_IFADDR_STATE_DEAD) {
3828 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3829 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3830 		} else {
3831 			if (idev->cnf.forwarding)
3832 				addrconf_leave_anycast(ifa);
3833 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3834 		}
3835 
3836 		write_lock_bh(&idev->lock);
3837 		if (!keep) {
3838 			list_del_rcu(&ifa->if_list);
3839 			in6_ifa_put(ifa);
3840 		}
3841 	}
3842 
3843 	write_unlock_bh(&idev->lock);
3844 
3845 	/* Step 5: Discard anycast and multicast list */
3846 	if (how) {
3847 		ipv6_ac_destroy_dev(idev);
3848 		ipv6_mc_destroy_dev(idev);
3849 	} else {
3850 		ipv6_mc_down(idev);
3851 	}
3852 
3853 	idev->tstamp = jiffies;
3854 
3855 	/* Last: Shot the device (if unregistered) */
3856 	if (how) {
3857 		addrconf_sysctl_unregister(idev);
3858 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3859 		neigh_ifdown(&nd_tbl, dev);
3860 		in6_dev_put(idev);
3861 	}
3862 	return 0;
3863 }
3864 
3865 static void addrconf_rs_timer(struct timer_list *t)
3866 {
3867 	struct inet6_dev *idev = from_timer(idev, t, rs_timer);
3868 	struct net_device *dev = idev->dev;
3869 	struct in6_addr lladdr;
3870 
3871 	write_lock(&idev->lock);
3872 	if (idev->dead || !(idev->if_flags & IF_READY))
3873 		goto out;
3874 
3875 	if (!ipv6_accept_ra(idev))
3876 		goto out;
3877 
3878 	/* Announcement received after solicitation was sent */
3879 	if (idev->if_flags & IF_RA_RCVD)
3880 		goto out;
3881 
3882 	if (idev->rs_probes++ < idev->cnf.rtr_solicits || idev->cnf.rtr_solicits < 0) {
3883 		write_unlock(&idev->lock);
3884 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3885 			ndisc_send_rs(dev, &lladdr,
3886 				      &in6addr_linklocal_allrouters);
3887 		else
3888 			goto put;
3889 
3890 		write_lock(&idev->lock);
3891 		idev->rs_interval = rfc3315_s14_backoff_update(
3892 			idev->rs_interval, idev->cnf.rtr_solicit_max_interval);
3893 		/* The wait after the last probe can be shorter */
3894 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3895 					     idev->cnf.rtr_solicits) ?
3896 				      idev->cnf.rtr_solicit_delay :
3897 				      idev->rs_interval);
3898 	} else {
3899 		/*
3900 		 * Note: we do not support deprecated "all on-link"
3901 		 * assumption any longer.
3902 		 */
3903 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3904 	}
3905 
3906 out:
3907 	write_unlock(&idev->lock);
3908 put:
3909 	in6_dev_put(idev);
3910 }
3911 
3912 /*
3913  *	Duplicate Address Detection
3914  */
3915 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3916 {
3917 	unsigned long rand_num;
3918 	struct inet6_dev *idev = ifp->idev;
3919 	u64 nonce;
3920 
3921 	if (ifp->flags & IFA_F_OPTIMISTIC)
3922 		rand_num = 0;
3923 	else
3924 		rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3925 
3926 	nonce = 0;
3927 	if (idev->cnf.enhanced_dad ||
3928 	    dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad) {
3929 		do
3930 			get_random_bytes(&nonce, 6);
3931 		while (nonce == 0);
3932 	}
3933 	ifp->dad_nonce = nonce;
3934 	ifp->dad_probes = idev->cnf.dad_transmits;
3935 	addrconf_mod_dad_work(ifp, rand_num);
3936 }
3937 
3938 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3939 {
3940 	struct inet6_dev *idev = ifp->idev;
3941 	struct net_device *dev = idev->dev;
3942 	bool bump_id, notify = false;
3943 	struct net *net;
3944 
3945 	addrconf_join_solict(dev, &ifp->addr);
3946 
3947 	prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3948 
3949 	read_lock_bh(&idev->lock);
3950 	spin_lock(&ifp->lock);
3951 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3952 		goto out;
3953 
3954 	net = dev_net(dev);
3955 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3956 	    (net->ipv6.devconf_all->accept_dad < 1 &&
3957 	     idev->cnf.accept_dad < 1) ||
3958 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3959 	    ifp->flags & IFA_F_NODAD) {
3960 		bool send_na = false;
3961 
3962 		if (ifp->flags & IFA_F_TENTATIVE &&
3963 		    !(ifp->flags & IFA_F_OPTIMISTIC))
3964 			send_na = true;
3965 		bump_id = ifp->flags & IFA_F_TENTATIVE;
3966 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3967 		spin_unlock(&ifp->lock);
3968 		read_unlock_bh(&idev->lock);
3969 
3970 		addrconf_dad_completed(ifp, bump_id, send_na);
3971 		return;
3972 	}
3973 
3974 	if (!(idev->if_flags & IF_READY)) {
3975 		spin_unlock(&ifp->lock);
3976 		read_unlock_bh(&idev->lock);
3977 		/*
3978 		 * If the device is not ready:
3979 		 * - keep it tentative if it is a permanent address.
3980 		 * - otherwise, kill it.
3981 		 */
3982 		in6_ifa_hold(ifp);
3983 		addrconf_dad_stop(ifp, 0);
3984 		return;
3985 	}
3986 
3987 	/*
3988 	 * Optimistic nodes can start receiving
3989 	 * Frames right away
3990 	 */
3991 	if (ifp->flags & IFA_F_OPTIMISTIC) {
3992 		ip6_ins_rt(net, ifp->rt);
3993 		if (ipv6_use_optimistic_addr(net, idev)) {
3994 			/* Because optimistic nodes can use this address,
3995 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
3996 			 */
3997 			notify = true;
3998 		}
3999 	}
4000 
4001 	addrconf_dad_kick(ifp);
4002 out:
4003 	spin_unlock(&ifp->lock);
4004 	read_unlock_bh(&idev->lock);
4005 	if (notify)
4006 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
4007 }
4008 
4009 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
4010 {
4011 	bool begin_dad = false;
4012 
4013 	spin_lock_bh(&ifp->lock);
4014 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
4015 		ifp->state = INET6_IFADDR_STATE_PREDAD;
4016 		begin_dad = true;
4017 	}
4018 	spin_unlock_bh(&ifp->lock);
4019 
4020 	if (begin_dad)
4021 		addrconf_mod_dad_work(ifp, 0);
4022 }
4023 
4024 static void addrconf_dad_work(struct work_struct *w)
4025 {
4026 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
4027 						struct inet6_ifaddr,
4028 						dad_work);
4029 	struct inet6_dev *idev = ifp->idev;
4030 	bool bump_id, disable_ipv6 = false;
4031 	struct in6_addr mcaddr;
4032 
4033 	enum {
4034 		DAD_PROCESS,
4035 		DAD_BEGIN,
4036 		DAD_ABORT,
4037 	} action = DAD_PROCESS;
4038 
4039 	rtnl_lock();
4040 
4041 	spin_lock_bh(&ifp->lock);
4042 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
4043 		action = DAD_BEGIN;
4044 		ifp->state = INET6_IFADDR_STATE_DAD;
4045 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
4046 		action = DAD_ABORT;
4047 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
4048 
4049 		if ((dev_net(idev->dev)->ipv6.devconf_all->accept_dad > 1 ||
4050 		     idev->cnf.accept_dad > 1) &&
4051 		    !idev->cnf.disable_ipv6 &&
4052 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
4053 			struct in6_addr addr;
4054 
4055 			addr.s6_addr32[0] = htonl(0xfe800000);
4056 			addr.s6_addr32[1] = 0;
4057 
4058 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
4059 			    ipv6_addr_equal(&ifp->addr, &addr)) {
4060 				/* DAD failed for link-local based on MAC */
4061 				idev->cnf.disable_ipv6 = 1;
4062 
4063 				pr_info("%s: IPv6 being disabled!\n",
4064 					ifp->idev->dev->name);
4065 				disable_ipv6 = true;
4066 			}
4067 		}
4068 	}
4069 	spin_unlock_bh(&ifp->lock);
4070 
4071 	if (action == DAD_BEGIN) {
4072 		addrconf_dad_begin(ifp);
4073 		goto out;
4074 	} else if (action == DAD_ABORT) {
4075 		in6_ifa_hold(ifp);
4076 		addrconf_dad_stop(ifp, 1);
4077 		if (disable_ipv6)
4078 			addrconf_ifdown(idev->dev, 0);
4079 		goto out;
4080 	}
4081 
4082 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
4083 		goto out;
4084 
4085 	write_lock_bh(&idev->lock);
4086 	if (idev->dead || !(idev->if_flags & IF_READY)) {
4087 		write_unlock_bh(&idev->lock);
4088 		goto out;
4089 	}
4090 
4091 	spin_lock(&ifp->lock);
4092 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
4093 		spin_unlock(&ifp->lock);
4094 		write_unlock_bh(&idev->lock);
4095 		goto out;
4096 	}
4097 
4098 	if (ifp->dad_probes == 0) {
4099 		bool send_na = false;
4100 
4101 		/*
4102 		 * DAD was successful
4103 		 */
4104 
4105 		if (ifp->flags & IFA_F_TENTATIVE &&
4106 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4107 			send_na = true;
4108 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4109 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4110 		spin_unlock(&ifp->lock);
4111 		write_unlock_bh(&idev->lock);
4112 
4113 		addrconf_dad_completed(ifp, bump_id, send_na);
4114 
4115 		goto out;
4116 	}
4117 
4118 	ifp->dad_probes--;
4119 	addrconf_mod_dad_work(ifp,
4120 			      NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME));
4121 	spin_unlock(&ifp->lock);
4122 	write_unlock_bh(&idev->lock);
4123 
4124 	/* send a neighbour solicitation for our addr */
4125 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4126 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4127 		      ifp->dad_nonce);
4128 out:
4129 	in6_ifa_put(ifp);
4130 	rtnl_unlock();
4131 }
4132 
4133 /* ifp->idev must be at least read locked */
4134 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4135 {
4136 	struct inet6_ifaddr *ifpiter;
4137 	struct inet6_dev *idev = ifp->idev;
4138 
4139 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4140 		if (ifpiter->scope > IFA_LINK)
4141 			break;
4142 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4143 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4144 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4145 		    IFA_F_PERMANENT)
4146 			return false;
4147 	}
4148 	return true;
4149 }
4150 
4151 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
4152 				   bool send_na)
4153 {
4154 	struct net_device *dev = ifp->idev->dev;
4155 	struct in6_addr lladdr;
4156 	bool send_rs, send_mld;
4157 
4158 	addrconf_del_dad_work(ifp);
4159 
4160 	/*
4161 	 *	Configure the address for reception. Now it is valid.
4162 	 */
4163 
4164 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4165 
4166 	/* If added prefix is link local and we are prepared to process
4167 	   router advertisements, start sending router solicitations.
4168 	 */
4169 
4170 	read_lock_bh(&ifp->idev->lock);
4171 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4172 	send_rs = send_mld &&
4173 		  ipv6_accept_ra(ifp->idev) &&
4174 		  ifp->idev->cnf.rtr_solicits != 0 &&
4175 		  (dev->flags&IFF_LOOPBACK) == 0;
4176 	read_unlock_bh(&ifp->idev->lock);
4177 
4178 	/* While dad is in progress mld report's source address is in6_addrany.
4179 	 * Resend with proper ll now.
4180 	 */
4181 	if (send_mld)
4182 		ipv6_mc_dad_complete(ifp->idev);
4183 
4184 	/* send unsolicited NA if enabled */
4185 	if (send_na &&
4186 	    (ifp->idev->cnf.ndisc_notify ||
4187 	     dev_net(dev)->ipv6.devconf_all->ndisc_notify)) {
4188 		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifp->addr,
4189 			      /*router=*/ !!ifp->idev->cnf.forwarding,
4190 			      /*solicited=*/ false, /*override=*/ true,
4191 			      /*inc_opt=*/ true);
4192 	}
4193 
4194 	if (send_rs) {
4195 		/*
4196 		 *	If a host as already performed a random delay
4197 		 *	[...] as part of DAD [...] there is no need
4198 		 *	to delay again before sending the first RS
4199 		 */
4200 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4201 			return;
4202 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4203 
4204 		write_lock_bh(&ifp->idev->lock);
4205 		spin_lock(&ifp->lock);
4206 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4207 			ifp->idev->cnf.rtr_solicit_interval);
4208 		ifp->idev->rs_probes = 1;
4209 		ifp->idev->if_flags |= IF_RS_SENT;
4210 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4211 		spin_unlock(&ifp->lock);
4212 		write_unlock_bh(&ifp->idev->lock);
4213 	}
4214 
4215 	if (bump_id)
4216 		rt_genid_bump_ipv6(dev_net(dev));
4217 
4218 	/* Make sure that a new temporary address will be created
4219 	 * before this temporary address becomes deprecated.
4220 	 */
4221 	if (ifp->flags & IFA_F_TEMPORARY)
4222 		addrconf_verify_rtnl();
4223 }
4224 
4225 static void addrconf_dad_run(struct inet6_dev *idev, bool restart)
4226 {
4227 	struct inet6_ifaddr *ifp;
4228 
4229 	read_lock_bh(&idev->lock);
4230 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4231 		spin_lock(&ifp->lock);
4232 		if ((ifp->flags & IFA_F_TENTATIVE &&
4233 		     ifp->state == INET6_IFADDR_STATE_DAD) || restart) {
4234 			if (restart)
4235 				ifp->state = INET6_IFADDR_STATE_PREDAD;
4236 			addrconf_dad_kick(ifp);
4237 		}
4238 		spin_unlock(&ifp->lock);
4239 	}
4240 	read_unlock_bh(&idev->lock);
4241 }
4242 
4243 #ifdef CONFIG_PROC_FS
4244 struct if6_iter_state {
4245 	struct seq_net_private p;
4246 	int bucket;
4247 	int offset;
4248 };
4249 
4250 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4251 {
4252 	struct if6_iter_state *state = seq->private;
4253 	struct net *net = seq_file_net(seq);
4254 	struct inet6_ifaddr *ifa = NULL;
4255 	int p = 0;
4256 
4257 	/* initial bucket if pos is 0 */
4258 	if (pos == 0) {
4259 		state->bucket = 0;
4260 		state->offset = 0;
4261 	}
4262 
4263 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4264 		hlist_for_each_entry_rcu(ifa, &inet6_addr_lst[state->bucket],
4265 					 addr_lst) {
4266 			if (!net_eq(dev_net(ifa->idev->dev), net))
4267 				continue;
4268 			/* sync with offset */
4269 			if (p < state->offset) {
4270 				p++;
4271 				continue;
4272 			}
4273 			return ifa;
4274 		}
4275 
4276 		/* prepare for next bucket */
4277 		state->offset = 0;
4278 		p = 0;
4279 	}
4280 	return NULL;
4281 }
4282 
4283 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4284 					 struct inet6_ifaddr *ifa)
4285 {
4286 	struct if6_iter_state *state = seq->private;
4287 	struct net *net = seq_file_net(seq);
4288 
4289 	hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4290 		if (!net_eq(dev_net(ifa->idev->dev), net))
4291 			continue;
4292 		state->offset++;
4293 		return ifa;
4294 	}
4295 
4296 	state->offset = 0;
4297 	while (++state->bucket < IN6_ADDR_HSIZE) {
4298 		hlist_for_each_entry_rcu(ifa,
4299 				     &inet6_addr_lst[state->bucket], addr_lst) {
4300 			if (!net_eq(dev_net(ifa->idev->dev), net))
4301 				continue;
4302 			return ifa;
4303 		}
4304 	}
4305 
4306 	return NULL;
4307 }
4308 
4309 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4310 	__acquires(rcu)
4311 {
4312 	rcu_read_lock();
4313 	return if6_get_first(seq, *pos);
4314 }
4315 
4316 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4317 {
4318 	struct inet6_ifaddr *ifa;
4319 
4320 	ifa = if6_get_next(seq, v);
4321 	++*pos;
4322 	return ifa;
4323 }
4324 
4325 static void if6_seq_stop(struct seq_file *seq, void *v)
4326 	__releases(rcu)
4327 {
4328 	rcu_read_unlock();
4329 }
4330 
4331 static int if6_seq_show(struct seq_file *seq, void *v)
4332 {
4333 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4334 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4335 		   &ifp->addr,
4336 		   ifp->idev->dev->ifindex,
4337 		   ifp->prefix_len,
4338 		   ifp->scope,
4339 		   (u8) ifp->flags,
4340 		   ifp->idev->dev->name);
4341 	return 0;
4342 }
4343 
4344 static const struct seq_operations if6_seq_ops = {
4345 	.start	= if6_seq_start,
4346 	.next	= if6_seq_next,
4347 	.show	= if6_seq_show,
4348 	.stop	= if6_seq_stop,
4349 };
4350 
4351 static int __net_init if6_proc_net_init(struct net *net)
4352 {
4353 	if (!proc_create_net("if_inet6", 0444, net->proc_net, &if6_seq_ops,
4354 			sizeof(struct if6_iter_state)))
4355 		return -ENOMEM;
4356 	return 0;
4357 }
4358 
4359 static void __net_exit if6_proc_net_exit(struct net *net)
4360 {
4361 	remove_proc_entry("if_inet6", net->proc_net);
4362 }
4363 
4364 static struct pernet_operations if6_proc_net_ops = {
4365 	.init = if6_proc_net_init,
4366 	.exit = if6_proc_net_exit,
4367 };
4368 
4369 int __init if6_proc_init(void)
4370 {
4371 	return register_pernet_subsys(&if6_proc_net_ops);
4372 }
4373 
4374 void if6_proc_exit(void)
4375 {
4376 	unregister_pernet_subsys(&if6_proc_net_ops);
4377 }
4378 #endif	/* CONFIG_PROC_FS */
4379 
4380 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4381 /* Check if address is a home address configured on any interface. */
4382 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4383 {
4384 	unsigned int hash = inet6_addr_hash(net, addr);
4385 	struct inet6_ifaddr *ifp = NULL;
4386 	int ret = 0;
4387 
4388 	rcu_read_lock();
4389 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
4390 		if (!net_eq(dev_net(ifp->idev->dev), net))
4391 			continue;
4392 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4393 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4394 			ret = 1;
4395 			break;
4396 		}
4397 	}
4398 	rcu_read_unlock();
4399 	return ret;
4400 }
4401 #endif
4402 
4403 /*
4404  *	Periodic address status verification
4405  */
4406 
4407 static void addrconf_verify_rtnl(void)
4408 {
4409 	unsigned long now, next, next_sec, next_sched;
4410 	struct inet6_ifaddr *ifp;
4411 	int i;
4412 
4413 	ASSERT_RTNL();
4414 
4415 	rcu_read_lock_bh();
4416 	now = jiffies;
4417 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4418 
4419 	cancel_delayed_work(&addr_chk_work);
4420 
4421 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4422 restart:
4423 		hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
4424 			unsigned long age;
4425 
4426 			/* When setting preferred_lft to a value not zero or
4427 			 * infinity, while valid_lft is infinity
4428 			 * IFA_F_PERMANENT has a non-infinity life time.
4429 			 */
4430 			if ((ifp->flags & IFA_F_PERMANENT) &&
4431 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4432 				continue;
4433 
4434 			spin_lock(&ifp->lock);
4435 			/* We try to batch several events at once. */
4436 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4437 
4438 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4439 			    age >= ifp->valid_lft) {
4440 				spin_unlock(&ifp->lock);
4441 				in6_ifa_hold(ifp);
4442 				ipv6_del_addr(ifp);
4443 				goto restart;
4444 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4445 				spin_unlock(&ifp->lock);
4446 				continue;
4447 			} else if (age >= ifp->prefered_lft) {
4448 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4449 				int deprecate = 0;
4450 
4451 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4452 					deprecate = 1;
4453 					ifp->flags |= IFA_F_DEPRECATED;
4454 				}
4455 
4456 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4457 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4458 					next = ifp->tstamp + ifp->valid_lft * HZ;
4459 
4460 				spin_unlock(&ifp->lock);
4461 
4462 				if (deprecate) {
4463 					in6_ifa_hold(ifp);
4464 
4465 					ipv6_ifa_notify(0, ifp);
4466 					in6_ifa_put(ifp);
4467 					goto restart;
4468 				}
4469 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
4470 				   !(ifp->flags&IFA_F_TENTATIVE)) {
4471 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
4472 					ifp->idev->cnf.dad_transmits *
4473 					NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME) / HZ;
4474 
4475 				if (age >= ifp->prefered_lft - regen_advance) {
4476 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4477 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4478 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4479 					if (!ifp->regen_count && ifpub) {
4480 						ifp->regen_count++;
4481 						in6_ifa_hold(ifp);
4482 						in6_ifa_hold(ifpub);
4483 						spin_unlock(&ifp->lock);
4484 
4485 						spin_lock(&ifpub->lock);
4486 						ifpub->regen_count = 0;
4487 						spin_unlock(&ifpub->lock);
4488 						rcu_read_unlock_bh();
4489 						ipv6_create_tempaddr(ifpub, ifp, true);
4490 						in6_ifa_put(ifpub);
4491 						in6_ifa_put(ifp);
4492 						rcu_read_lock_bh();
4493 						goto restart;
4494 					}
4495 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4496 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4497 				spin_unlock(&ifp->lock);
4498 			} else {
4499 				/* ifp->prefered_lft <= ifp->valid_lft */
4500 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4501 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4502 				spin_unlock(&ifp->lock);
4503 			}
4504 		}
4505 	}
4506 
4507 	next_sec = round_jiffies_up(next);
4508 	next_sched = next;
4509 
4510 	/* If rounded timeout is accurate enough, accept it. */
4511 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4512 		next_sched = next_sec;
4513 
4514 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4515 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4516 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4517 
4518 	pr_debug("now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4519 		 now, next, next_sec, next_sched);
4520 	mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
4521 	rcu_read_unlock_bh();
4522 }
4523 
4524 static void addrconf_verify_work(struct work_struct *w)
4525 {
4526 	rtnl_lock();
4527 	addrconf_verify_rtnl();
4528 	rtnl_unlock();
4529 }
4530 
4531 static void addrconf_verify(void)
4532 {
4533 	mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
4534 }
4535 
4536 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4537 				     struct in6_addr **peer_pfx)
4538 {
4539 	struct in6_addr *pfx = NULL;
4540 
4541 	*peer_pfx = NULL;
4542 
4543 	if (addr)
4544 		pfx = nla_data(addr);
4545 
4546 	if (local) {
4547 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4548 			*peer_pfx = pfx;
4549 		pfx = nla_data(local);
4550 	}
4551 
4552 	return pfx;
4553 }
4554 
4555 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4556 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4557 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4558 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4559 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4560 	[IFA_RT_PRIORITY]	= { .len = sizeof(u32) },
4561 	[IFA_TARGET_NETNSID]	= { .type = NLA_S32 },
4562 };
4563 
4564 static int
4565 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4566 		  struct netlink_ext_ack *extack)
4567 {
4568 	struct net *net = sock_net(skb->sk);
4569 	struct ifaddrmsg *ifm;
4570 	struct nlattr *tb[IFA_MAX+1];
4571 	struct in6_addr *pfx, *peer_pfx;
4572 	u32 ifa_flags;
4573 	int err;
4574 
4575 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4576 				     ifa_ipv6_policy, extack);
4577 	if (err < 0)
4578 		return err;
4579 
4580 	ifm = nlmsg_data(nlh);
4581 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4582 	if (!pfx)
4583 		return -EINVAL;
4584 
4585 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4586 
4587 	/* We ignore other flags so far. */
4588 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4589 
4590 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4591 			      ifm->ifa_prefixlen);
4592 }
4593 
4594 static int modify_prefix_route(struct inet6_ifaddr *ifp,
4595 			       unsigned long expires, u32 flags,
4596 			       bool modify_peer)
4597 {
4598 	struct fib6_info *f6i;
4599 	u32 prio;
4600 
4601 	f6i = addrconf_get_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4602 					ifp->prefix_len,
4603 					ifp->idev->dev, 0, RTF_DEFAULT, true);
4604 	if (!f6i)
4605 		return -ENOENT;
4606 
4607 	prio = ifp->rt_priority ? : IP6_RT_PRIO_ADDRCONF;
4608 	if (f6i->fib6_metric != prio) {
4609 		/* delete old one */
4610 		ip6_del_rt(dev_net(ifp->idev->dev), f6i);
4611 
4612 		/* add new one */
4613 		addrconf_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4614 				      ifp->prefix_len,
4615 				      ifp->rt_priority, ifp->idev->dev,
4616 				      expires, flags, GFP_KERNEL);
4617 	} else {
4618 		if (!expires)
4619 			fib6_clean_expires(f6i);
4620 		else
4621 			fib6_set_expires(f6i, expires);
4622 
4623 		fib6_info_release(f6i);
4624 	}
4625 
4626 	return 0;
4627 }
4628 
4629 static int inet6_addr_modify(struct inet6_ifaddr *ifp, struct ifa6_config *cfg)
4630 {
4631 	u32 flags;
4632 	clock_t expires;
4633 	unsigned long timeout;
4634 	bool was_managetempaddr;
4635 	bool had_prefixroute;
4636 	bool new_peer = false;
4637 
4638 	ASSERT_RTNL();
4639 
4640 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
4641 		return -EINVAL;
4642 
4643 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR &&
4644 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4645 		return -EINVAL;
4646 
4647 	if (!(ifp->flags & IFA_F_TENTATIVE) || ifp->flags & IFA_F_DADFAILED)
4648 		cfg->ifa_flags &= ~IFA_F_OPTIMISTIC;
4649 
4650 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
4651 	if (addrconf_finite_timeout(timeout)) {
4652 		expires = jiffies_to_clock_t(timeout * HZ);
4653 		cfg->valid_lft = timeout;
4654 		flags = RTF_EXPIRES;
4655 	} else {
4656 		expires = 0;
4657 		flags = 0;
4658 		cfg->ifa_flags |= IFA_F_PERMANENT;
4659 	}
4660 
4661 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
4662 	if (addrconf_finite_timeout(timeout)) {
4663 		if (timeout == 0)
4664 			cfg->ifa_flags |= IFA_F_DEPRECATED;
4665 		cfg->preferred_lft = timeout;
4666 	}
4667 
4668 	if (cfg->peer_pfx &&
4669 	    memcmp(&ifp->peer_addr, cfg->peer_pfx, sizeof(struct in6_addr))) {
4670 		if (!ipv6_addr_any(&ifp->peer_addr))
4671 			cleanup_prefix_route(ifp, expires, true, true);
4672 		new_peer = true;
4673 	}
4674 
4675 	spin_lock_bh(&ifp->lock);
4676 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4677 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4678 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4679 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4680 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4681 			IFA_F_NOPREFIXROUTE);
4682 	ifp->flags |= cfg->ifa_flags;
4683 	ifp->tstamp = jiffies;
4684 	ifp->valid_lft = cfg->valid_lft;
4685 	ifp->prefered_lft = cfg->preferred_lft;
4686 
4687 	if (cfg->rt_priority && cfg->rt_priority != ifp->rt_priority)
4688 		ifp->rt_priority = cfg->rt_priority;
4689 
4690 	if (new_peer)
4691 		ifp->peer_addr = *cfg->peer_pfx;
4692 
4693 	spin_unlock_bh(&ifp->lock);
4694 	if (!(ifp->flags&IFA_F_TENTATIVE))
4695 		ipv6_ifa_notify(0, ifp);
4696 
4697 	if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
4698 		int rc = -ENOENT;
4699 
4700 		if (had_prefixroute)
4701 			rc = modify_prefix_route(ifp, expires, flags, false);
4702 
4703 		/* prefix route could have been deleted; if so restore it */
4704 		if (rc == -ENOENT) {
4705 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4706 					      ifp->rt_priority, ifp->idev->dev,
4707 					      expires, flags, GFP_KERNEL);
4708 		}
4709 
4710 		if (had_prefixroute && !ipv6_addr_any(&ifp->peer_addr))
4711 			rc = modify_prefix_route(ifp, expires, flags, true);
4712 
4713 		if (rc == -ENOENT && !ipv6_addr_any(&ifp->peer_addr)) {
4714 			addrconf_prefix_route(&ifp->peer_addr, ifp->prefix_len,
4715 					      ifp->rt_priority, ifp->idev->dev,
4716 					      expires, flags, GFP_KERNEL);
4717 		}
4718 	} else if (had_prefixroute) {
4719 		enum cleanup_prefix_rt_t action;
4720 		unsigned long rt_expires;
4721 
4722 		write_lock_bh(&ifp->idev->lock);
4723 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4724 		write_unlock_bh(&ifp->idev->lock);
4725 
4726 		if (action != CLEANUP_PREFIX_RT_NOP) {
4727 			cleanup_prefix_route(ifp, rt_expires,
4728 				action == CLEANUP_PREFIX_RT_DEL, false);
4729 		}
4730 	}
4731 
4732 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4733 		if (was_managetempaddr &&
4734 		    !(ifp->flags & IFA_F_MANAGETEMPADDR)) {
4735 			cfg->valid_lft = 0;
4736 			cfg->preferred_lft = 0;
4737 		}
4738 		manage_tempaddrs(ifp->idev, ifp, cfg->valid_lft,
4739 				 cfg->preferred_lft, !was_managetempaddr,
4740 				 jiffies);
4741 	}
4742 
4743 	addrconf_verify_rtnl();
4744 
4745 	return 0;
4746 }
4747 
4748 static int
4749 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4750 		  struct netlink_ext_ack *extack)
4751 {
4752 	struct net *net = sock_net(skb->sk);
4753 	struct ifaddrmsg *ifm;
4754 	struct nlattr *tb[IFA_MAX+1];
4755 	struct in6_addr *peer_pfx;
4756 	struct inet6_ifaddr *ifa;
4757 	struct net_device *dev;
4758 	struct inet6_dev *idev;
4759 	struct ifa6_config cfg;
4760 	int err;
4761 
4762 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4763 				     ifa_ipv6_policy, extack);
4764 	if (err < 0)
4765 		return err;
4766 
4767 	memset(&cfg, 0, sizeof(cfg));
4768 
4769 	ifm = nlmsg_data(nlh);
4770 	cfg.pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4771 	if (!cfg.pfx)
4772 		return -EINVAL;
4773 
4774 	cfg.peer_pfx = peer_pfx;
4775 	cfg.plen = ifm->ifa_prefixlen;
4776 	if (tb[IFA_RT_PRIORITY])
4777 		cfg.rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
4778 
4779 	cfg.valid_lft = INFINITY_LIFE_TIME;
4780 	cfg.preferred_lft = INFINITY_LIFE_TIME;
4781 
4782 	if (tb[IFA_CACHEINFO]) {
4783 		struct ifa_cacheinfo *ci;
4784 
4785 		ci = nla_data(tb[IFA_CACHEINFO]);
4786 		cfg.valid_lft = ci->ifa_valid;
4787 		cfg.preferred_lft = ci->ifa_prefered;
4788 	}
4789 
4790 	dev =  __dev_get_by_index(net, ifm->ifa_index);
4791 	if (!dev)
4792 		return -ENODEV;
4793 
4794 	if (tb[IFA_FLAGS])
4795 		cfg.ifa_flags = nla_get_u32(tb[IFA_FLAGS]);
4796 	else
4797 		cfg.ifa_flags = ifm->ifa_flags;
4798 
4799 	/* We ignore other flags so far. */
4800 	cfg.ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS |
4801 			 IFA_F_MANAGETEMPADDR | IFA_F_NOPREFIXROUTE |
4802 			 IFA_F_MCAUTOJOIN | IFA_F_OPTIMISTIC;
4803 
4804 	idev = ipv6_find_idev(dev);
4805 	if (IS_ERR(idev))
4806 		return PTR_ERR(idev);
4807 
4808 	if (!ipv6_allow_optimistic_dad(net, idev))
4809 		cfg.ifa_flags &= ~IFA_F_OPTIMISTIC;
4810 
4811 	if (cfg.ifa_flags & IFA_F_NODAD &&
4812 	    cfg.ifa_flags & IFA_F_OPTIMISTIC) {
4813 		NL_SET_ERR_MSG(extack, "IFA_F_NODAD and IFA_F_OPTIMISTIC are mutually exclusive");
4814 		return -EINVAL;
4815 	}
4816 
4817 	ifa = ipv6_get_ifaddr(net, cfg.pfx, dev, 1);
4818 	if (!ifa) {
4819 		/*
4820 		 * It would be best to check for !NLM_F_CREATE here but
4821 		 * userspace already relies on not having to provide this.
4822 		 */
4823 		return inet6_addr_add(net, ifm->ifa_index, &cfg, extack);
4824 	}
4825 
4826 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
4827 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
4828 		err = -EEXIST;
4829 	else
4830 		err = inet6_addr_modify(ifa, &cfg);
4831 
4832 	in6_ifa_put(ifa);
4833 
4834 	return err;
4835 }
4836 
4837 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
4838 			  u8 scope, int ifindex)
4839 {
4840 	struct ifaddrmsg *ifm;
4841 
4842 	ifm = nlmsg_data(nlh);
4843 	ifm->ifa_family = AF_INET6;
4844 	ifm->ifa_prefixlen = prefixlen;
4845 	ifm->ifa_flags = flags;
4846 	ifm->ifa_scope = scope;
4847 	ifm->ifa_index = ifindex;
4848 }
4849 
4850 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
4851 			 unsigned long tstamp, u32 preferred, u32 valid)
4852 {
4853 	struct ifa_cacheinfo ci;
4854 
4855 	ci.cstamp = cstamp_delta(cstamp);
4856 	ci.tstamp = cstamp_delta(tstamp);
4857 	ci.ifa_prefered = preferred;
4858 	ci.ifa_valid = valid;
4859 
4860 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
4861 }
4862 
4863 static inline int rt_scope(int ifa_scope)
4864 {
4865 	if (ifa_scope & IFA_HOST)
4866 		return RT_SCOPE_HOST;
4867 	else if (ifa_scope & IFA_LINK)
4868 		return RT_SCOPE_LINK;
4869 	else if (ifa_scope & IFA_SITE)
4870 		return RT_SCOPE_SITE;
4871 	else
4872 		return RT_SCOPE_UNIVERSE;
4873 }
4874 
4875 static inline int inet6_ifaddr_msgsize(void)
4876 {
4877 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
4878 	       + nla_total_size(16) /* IFA_LOCAL */
4879 	       + nla_total_size(16) /* IFA_ADDRESS */
4880 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
4881 	       + nla_total_size(4)  /* IFA_FLAGS */
4882 	       + nla_total_size(4)  /* IFA_RT_PRIORITY */;
4883 }
4884 
4885 enum addr_type_t {
4886 	UNICAST_ADDR,
4887 	MULTICAST_ADDR,
4888 	ANYCAST_ADDR,
4889 };
4890 
4891 struct inet6_fill_args {
4892 	u32 portid;
4893 	u32 seq;
4894 	int event;
4895 	unsigned int flags;
4896 	int netnsid;
4897 	int ifindex;
4898 	enum addr_type_t type;
4899 };
4900 
4901 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
4902 			     struct inet6_fill_args *args)
4903 {
4904 	struct nlmsghdr  *nlh;
4905 	u32 preferred, valid;
4906 
4907 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
4908 			sizeof(struct ifaddrmsg), args->flags);
4909 	if (!nlh)
4910 		return -EMSGSIZE;
4911 
4912 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
4913 		      ifa->idev->dev->ifindex);
4914 
4915 	if (args->netnsid >= 0 &&
4916 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
4917 		goto error;
4918 
4919 	if (!((ifa->flags&IFA_F_PERMANENT) &&
4920 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
4921 		preferred = ifa->prefered_lft;
4922 		valid = ifa->valid_lft;
4923 		if (preferred != INFINITY_LIFE_TIME) {
4924 			long tval = (jiffies - ifa->tstamp)/HZ;
4925 			if (preferred > tval)
4926 				preferred -= tval;
4927 			else
4928 				preferred = 0;
4929 			if (valid != INFINITY_LIFE_TIME) {
4930 				if (valid > tval)
4931 					valid -= tval;
4932 				else
4933 					valid = 0;
4934 			}
4935 		}
4936 	} else {
4937 		preferred = INFINITY_LIFE_TIME;
4938 		valid = INFINITY_LIFE_TIME;
4939 	}
4940 
4941 	if (!ipv6_addr_any(&ifa->peer_addr)) {
4942 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
4943 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
4944 			goto error;
4945 	} else
4946 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
4947 			goto error;
4948 
4949 	if (ifa->rt_priority &&
4950 	    nla_put_u32(skb, IFA_RT_PRIORITY, ifa->rt_priority))
4951 		goto error;
4952 
4953 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
4954 		goto error;
4955 
4956 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
4957 		goto error;
4958 
4959 	nlmsg_end(skb, nlh);
4960 	return 0;
4961 
4962 error:
4963 	nlmsg_cancel(skb, nlh);
4964 	return -EMSGSIZE;
4965 }
4966 
4967 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
4968 			       struct inet6_fill_args *args)
4969 {
4970 	struct nlmsghdr  *nlh;
4971 	u8 scope = RT_SCOPE_UNIVERSE;
4972 	int ifindex = ifmca->idev->dev->ifindex;
4973 
4974 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
4975 		scope = RT_SCOPE_SITE;
4976 
4977 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
4978 			sizeof(struct ifaddrmsg), args->flags);
4979 	if (!nlh)
4980 		return -EMSGSIZE;
4981 
4982 	if (args->netnsid >= 0 &&
4983 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
4984 		return -EMSGSIZE;
4985 
4986 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4987 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
4988 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
4989 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4990 		nlmsg_cancel(skb, nlh);
4991 		return -EMSGSIZE;
4992 	}
4993 
4994 	nlmsg_end(skb, nlh);
4995 	return 0;
4996 }
4997 
4998 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
4999 			       struct inet6_fill_args *args)
5000 {
5001 	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
5002 	int ifindex = dev ? dev->ifindex : 1;
5003 	struct nlmsghdr  *nlh;
5004 	u8 scope = RT_SCOPE_UNIVERSE;
5005 
5006 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
5007 		scope = RT_SCOPE_SITE;
5008 
5009 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5010 			sizeof(struct ifaddrmsg), args->flags);
5011 	if (!nlh)
5012 		return -EMSGSIZE;
5013 
5014 	if (args->netnsid >= 0 &&
5015 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
5016 		return -EMSGSIZE;
5017 
5018 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5019 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
5020 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
5021 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5022 		nlmsg_cancel(skb, nlh);
5023 		return -EMSGSIZE;
5024 	}
5025 
5026 	nlmsg_end(skb, nlh);
5027 	return 0;
5028 }
5029 
5030 /* called with rcu_read_lock() */
5031 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
5032 			  struct netlink_callback *cb, int s_ip_idx,
5033 			  struct inet6_fill_args *fillargs)
5034 {
5035 	struct ifmcaddr6 *ifmca;
5036 	struct ifacaddr6 *ifaca;
5037 	int ip_idx = 0;
5038 	int err = 1;
5039 
5040 	read_lock_bh(&idev->lock);
5041 	switch (fillargs->type) {
5042 	case UNICAST_ADDR: {
5043 		struct inet6_ifaddr *ifa;
5044 		fillargs->event = RTM_NEWADDR;
5045 
5046 		/* unicast address incl. temp addr */
5047 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
5048 			if (ip_idx < s_ip_idx)
5049 				goto next;
5050 			err = inet6_fill_ifaddr(skb, ifa, fillargs);
5051 			if (err < 0)
5052 				break;
5053 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
5054 next:
5055 			ip_idx++;
5056 		}
5057 		break;
5058 	}
5059 	case MULTICAST_ADDR:
5060 		fillargs->event = RTM_GETMULTICAST;
5061 
5062 		/* multicast address */
5063 		for (ifmca = idev->mc_list; ifmca;
5064 		     ifmca = ifmca->next, ip_idx++) {
5065 			if (ip_idx < s_ip_idx)
5066 				continue;
5067 			err = inet6_fill_ifmcaddr(skb, ifmca, fillargs);
5068 			if (err < 0)
5069 				break;
5070 		}
5071 		break;
5072 	case ANYCAST_ADDR:
5073 		fillargs->event = RTM_GETANYCAST;
5074 		/* anycast address */
5075 		for (ifaca = idev->ac_list; ifaca;
5076 		     ifaca = ifaca->aca_next, ip_idx++) {
5077 			if (ip_idx < s_ip_idx)
5078 				continue;
5079 			err = inet6_fill_ifacaddr(skb, ifaca, fillargs);
5080 			if (err < 0)
5081 				break;
5082 		}
5083 		break;
5084 	default:
5085 		break;
5086 	}
5087 	read_unlock_bh(&idev->lock);
5088 	cb->args[2] = ip_idx;
5089 	return err;
5090 }
5091 
5092 static int inet6_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
5093 				       struct inet6_fill_args *fillargs,
5094 				       struct net **tgt_net, struct sock *sk,
5095 				       struct netlink_callback *cb)
5096 {
5097 	struct netlink_ext_ack *extack = cb->extack;
5098 	struct nlattr *tb[IFA_MAX+1];
5099 	struct ifaddrmsg *ifm;
5100 	int err, i;
5101 
5102 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5103 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for address dump request");
5104 		return -EINVAL;
5105 	}
5106 
5107 	ifm = nlmsg_data(nlh);
5108 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5109 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address dump request");
5110 		return -EINVAL;
5111 	}
5112 
5113 	fillargs->ifindex = ifm->ifa_index;
5114 	if (fillargs->ifindex) {
5115 		cb->answer_flags |= NLM_F_DUMP_FILTERED;
5116 		fillargs->flags |= NLM_F_DUMP_FILTERED;
5117 	}
5118 
5119 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5120 					    ifa_ipv6_policy, extack);
5121 	if (err < 0)
5122 		return err;
5123 
5124 	for (i = 0; i <= IFA_MAX; ++i) {
5125 		if (!tb[i])
5126 			continue;
5127 
5128 		if (i == IFA_TARGET_NETNSID) {
5129 			struct net *net;
5130 
5131 			fillargs->netnsid = nla_get_s32(tb[i]);
5132 			net = rtnl_get_net_ns_capable(sk, fillargs->netnsid);
5133 			if (IS_ERR(net)) {
5134 				fillargs->netnsid = -1;
5135 				NL_SET_ERR_MSG_MOD(extack, "Invalid target network namespace id");
5136 				return PTR_ERR(net);
5137 			}
5138 			*tgt_net = net;
5139 		} else {
5140 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request");
5141 			return -EINVAL;
5142 		}
5143 	}
5144 
5145 	return 0;
5146 }
5147 
5148 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
5149 			   enum addr_type_t type)
5150 {
5151 	const struct nlmsghdr *nlh = cb->nlh;
5152 	struct inet6_fill_args fillargs = {
5153 		.portid = NETLINK_CB(cb->skb).portid,
5154 		.seq = cb->nlh->nlmsg_seq,
5155 		.flags = NLM_F_MULTI,
5156 		.netnsid = -1,
5157 		.type = type,
5158 	};
5159 	struct net *net = sock_net(skb->sk);
5160 	struct net *tgt_net = net;
5161 	int idx, s_idx, s_ip_idx;
5162 	int h, s_h;
5163 	struct net_device *dev;
5164 	struct inet6_dev *idev;
5165 	struct hlist_head *head;
5166 	int err = 0;
5167 
5168 	s_h = cb->args[0];
5169 	s_idx = idx = cb->args[1];
5170 	s_ip_idx = cb->args[2];
5171 
5172 	if (cb->strict_check) {
5173 		err = inet6_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
5174 						  skb->sk, cb);
5175 		if (err < 0)
5176 			goto put_tgt_net;
5177 
5178 		err = 0;
5179 		if (fillargs.ifindex) {
5180 			dev = __dev_get_by_index(tgt_net, fillargs.ifindex);
5181 			if (!dev) {
5182 				err = -ENODEV;
5183 				goto put_tgt_net;
5184 			}
5185 			idev = __in6_dev_get(dev);
5186 			if (idev) {
5187 				err = in6_dump_addrs(idev, skb, cb, s_ip_idx,
5188 						     &fillargs);
5189 				if (err > 0)
5190 					err = 0;
5191 			}
5192 			goto put_tgt_net;
5193 		}
5194 	}
5195 
5196 	rcu_read_lock();
5197 	cb->seq = atomic_read(&tgt_net->ipv6.dev_addr_genid) ^ tgt_net->dev_base_seq;
5198 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5199 		idx = 0;
5200 		head = &tgt_net->dev_index_head[h];
5201 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5202 			if (idx < s_idx)
5203 				goto cont;
5204 			if (h > s_h || idx > s_idx)
5205 				s_ip_idx = 0;
5206 			idev = __in6_dev_get(dev);
5207 			if (!idev)
5208 				goto cont;
5209 
5210 			if (in6_dump_addrs(idev, skb, cb, s_ip_idx,
5211 					   &fillargs) < 0)
5212 				goto done;
5213 cont:
5214 			idx++;
5215 		}
5216 	}
5217 done:
5218 	rcu_read_unlock();
5219 	cb->args[0] = h;
5220 	cb->args[1] = idx;
5221 put_tgt_net:
5222 	if (fillargs.netnsid >= 0)
5223 		put_net(tgt_net);
5224 
5225 	return skb->len ? : err;
5226 }
5227 
5228 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
5229 {
5230 	enum addr_type_t type = UNICAST_ADDR;
5231 
5232 	return inet6_dump_addr(skb, cb, type);
5233 }
5234 
5235 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
5236 {
5237 	enum addr_type_t type = MULTICAST_ADDR;
5238 
5239 	return inet6_dump_addr(skb, cb, type);
5240 }
5241 
5242 
5243 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
5244 {
5245 	enum addr_type_t type = ANYCAST_ADDR;
5246 
5247 	return inet6_dump_addr(skb, cb, type);
5248 }
5249 
5250 static int inet6_rtm_valid_getaddr_req(struct sk_buff *skb,
5251 				       const struct nlmsghdr *nlh,
5252 				       struct nlattr **tb,
5253 				       struct netlink_ext_ack *extack)
5254 {
5255 	struct ifaddrmsg *ifm;
5256 	int i, err;
5257 
5258 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5259 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for get address request");
5260 		return -EINVAL;
5261 	}
5262 
5263 	if (!netlink_strict_get_check(skb))
5264 		return nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
5265 					      ifa_ipv6_policy, extack);
5266 
5267 	ifm = nlmsg_data(nlh);
5268 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5269 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get address request");
5270 		return -EINVAL;
5271 	}
5272 
5273 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5274 					    ifa_ipv6_policy, extack);
5275 	if (err)
5276 		return err;
5277 
5278 	for (i = 0; i <= IFA_MAX; i++) {
5279 		if (!tb[i])
5280 			continue;
5281 
5282 		switch (i) {
5283 		case IFA_TARGET_NETNSID:
5284 		case IFA_ADDRESS:
5285 		case IFA_LOCAL:
5286 			break;
5287 		default:
5288 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get address request");
5289 			return -EINVAL;
5290 		}
5291 	}
5292 
5293 	return 0;
5294 }
5295 
5296 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5297 			     struct netlink_ext_ack *extack)
5298 {
5299 	struct net *net = sock_net(in_skb->sk);
5300 	struct inet6_fill_args fillargs = {
5301 		.portid = NETLINK_CB(in_skb).portid,
5302 		.seq = nlh->nlmsg_seq,
5303 		.event = RTM_NEWADDR,
5304 		.flags = 0,
5305 		.netnsid = -1,
5306 	};
5307 	struct net *tgt_net = net;
5308 	struct ifaddrmsg *ifm;
5309 	struct nlattr *tb[IFA_MAX+1];
5310 	struct in6_addr *addr = NULL, *peer;
5311 	struct net_device *dev = NULL;
5312 	struct inet6_ifaddr *ifa;
5313 	struct sk_buff *skb;
5314 	int err;
5315 
5316 	err = inet6_rtm_valid_getaddr_req(in_skb, nlh, tb, extack);
5317 	if (err < 0)
5318 		return err;
5319 
5320 	if (tb[IFA_TARGET_NETNSID]) {
5321 		fillargs.netnsid = nla_get_s32(tb[IFA_TARGET_NETNSID]);
5322 
5323 		tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(in_skb).sk,
5324 						  fillargs.netnsid);
5325 		if (IS_ERR(tgt_net))
5326 			return PTR_ERR(tgt_net);
5327 	}
5328 
5329 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
5330 	if (!addr)
5331 		return -EINVAL;
5332 
5333 	ifm = nlmsg_data(nlh);
5334 	if (ifm->ifa_index)
5335 		dev = dev_get_by_index(tgt_net, ifm->ifa_index);
5336 
5337 	ifa = ipv6_get_ifaddr(tgt_net, addr, dev, 1);
5338 	if (!ifa) {
5339 		err = -EADDRNOTAVAIL;
5340 		goto errout;
5341 	}
5342 
5343 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
5344 	if (!skb) {
5345 		err = -ENOBUFS;
5346 		goto errout_ifa;
5347 	}
5348 
5349 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5350 	if (err < 0) {
5351 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5352 		WARN_ON(err == -EMSGSIZE);
5353 		kfree_skb(skb);
5354 		goto errout_ifa;
5355 	}
5356 	err = rtnl_unicast(skb, tgt_net, NETLINK_CB(in_skb).portid);
5357 errout_ifa:
5358 	in6_ifa_put(ifa);
5359 errout:
5360 	if (dev)
5361 		dev_put(dev);
5362 	if (fillargs.netnsid >= 0)
5363 		put_net(tgt_net);
5364 
5365 	return err;
5366 }
5367 
5368 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
5369 {
5370 	struct sk_buff *skb;
5371 	struct net *net = dev_net(ifa->idev->dev);
5372 	struct inet6_fill_args fillargs = {
5373 		.portid = 0,
5374 		.seq = 0,
5375 		.event = event,
5376 		.flags = 0,
5377 		.netnsid = -1,
5378 	};
5379 	int err = -ENOBUFS;
5380 
5381 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
5382 	if (!skb)
5383 		goto errout;
5384 
5385 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5386 	if (err < 0) {
5387 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5388 		WARN_ON(err == -EMSGSIZE);
5389 		kfree_skb(skb);
5390 		goto errout;
5391 	}
5392 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5393 	return;
5394 errout:
5395 	if (err < 0)
5396 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5397 }
5398 
5399 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
5400 				__s32 *array, int bytes)
5401 {
5402 	BUG_ON(bytes < (DEVCONF_MAX * 4));
5403 
5404 	memset(array, 0, bytes);
5405 	array[DEVCONF_FORWARDING] = cnf->forwarding;
5406 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
5407 	array[DEVCONF_MTU6] = cnf->mtu6;
5408 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
5409 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
5410 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
5411 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
5412 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
5413 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5414 		jiffies_to_msecs(cnf->rtr_solicit_interval);
5415 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5416 		jiffies_to_msecs(cnf->rtr_solicit_max_interval);
5417 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5418 		jiffies_to_msecs(cnf->rtr_solicit_delay);
5419 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
5420 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5421 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
5422 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5423 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
5424 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
5425 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
5426 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
5427 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
5428 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
5429 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
5430 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
5431 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] = cnf->accept_ra_min_hop_limit;
5432 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
5433 #ifdef CONFIG_IPV6_ROUTER_PREF
5434 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
5435 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5436 		jiffies_to_msecs(cnf->rtr_probe_interval);
5437 #ifdef CONFIG_IPV6_ROUTE_INFO
5438 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] = cnf->accept_ra_rt_info_min_plen;
5439 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
5440 #endif
5441 #endif
5442 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
5443 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
5444 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5445 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
5446 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
5447 #endif
5448 #ifdef CONFIG_IPV6_MROUTE
5449 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
5450 #endif
5451 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
5452 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
5453 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
5454 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
5455 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
5456 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
5457 	array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
5458 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] = cnf->ignore_routes_with_linkdown;
5459 	/* we omit DEVCONF_STABLE_SECRET for now */
5460 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
5461 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
5462 	array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
5463 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
5464 	array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
5465 #ifdef CONFIG_IPV6_SEG6_HMAC
5466 	array[DEVCONF_SEG6_REQUIRE_HMAC] = cnf->seg6_require_hmac;
5467 #endif
5468 	array[DEVCONF_ENHANCED_DAD] = cnf->enhanced_dad;
5469 	array[DEVCONF_ADDR_GEN_MODE] = cnf->addr_gen_mode;
5470 	array[DEVCONF_DISABLE_POLICY] = cnf->disable_policy;
5471 	array[DEVCONF_NDISC_TCLASS] = cnf->ndisc_tclass;
5472 }
5473 
5474 static inline size_t inet6_ifla6_size(void)
5475 {
5476 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5477 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5478 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5479 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5480 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5481 	     + nla_total_size(sizeof(struct in6_addr)) /* IFLA_INET6_TOKEN */
5482 	     + nla_total_size(1) /* IFLA_INET6_ADDR_GEN_MODE */
5483 	     + 0;
5484 }
5485 
5486 static inline size_t inet6_if_nlmsg_size(void)
5487 {
5488 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5489 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5490 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5491 	       + nla_total_size(4) /* IFLA_MTU */
5492 	       + nla_total_size(4) /* IFLA_LINK */
5493 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5494 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5495 }
5496 
5497 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5498 					int bytes)
5499 {
5500 	int i;
5501 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5502 	BUG_ON(pad < 0);
5503 
5504 	/* Use put_unaligned() because stats may not be aligned for u64. */
5505 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5506 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5507 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5508 
5509 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5510 }
5511 
5512 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5513 					int bytes, size_t syncpoff)
5514 {
5515 	int i, c;
5516 	u64 buff[IPSTATS_MIB_MAX];
5517 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5518 
5519 	BUG_ON(pad < 0);
5520 
5521 	memset(buff, 0, sizeof(buff));
5522 	buff[0] = IPSTATS_MIB_MAX;
5523 
5524 	for_each_possible_cpu(c) {
5525 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5526 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5527 	}
5528 
5529 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5530 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5531 }
5532 
5533 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5534 			     int bytes)
5535 {
5536 	switch (attrtype) {
5537 	case IFLA_INET6_STATS:
5538 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5539 				     offsetof(struct ipstats_mib, syncp));
5540 		break;
5541 	case IFLA_INET6_ICMP6STATS:
5542 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5543 		break;
5544 	}
5545 }
5546 
5547 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5548 				  u32 ext_filter_mask)
5549 {
5550 	struct nlattr *nla;
5551 	struct ifla_cacheinfo ci;
5552 
5553 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
5554 		goto nla_put_failure;
5555 	ci.max_reasm_len = IPV6_MAXPLEN;
5556 	ci.tstamp = cstamp_delta(idev->tstamp);
5557 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5558 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5559 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5560 		goto nla_put_failure;
5561 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5562 	if (!nla)
5563 		goto nla_put_failure;
5564 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5565 
5566 	/* XXX - MC not implemented */
5567 
5568 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5569 		return 0;
5570 
5571 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5572 	if (!nla)
5573 		goto nla_put_failure;
5574 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5575 
5576 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5577 	if (!nla)
5578 		goto nla_put_failure;
5579 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5580 
5581 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5582 	if (!nla)
5583 		goto nla_put_failure;
5584 	read_lock_bh(&idev->lock);
5585 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5586 	read_unlock_bh(&idev->lock);
5587 
5588 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->cnf.addr_gen_mode))
5589 		goto nla_put_failure;
5590 
5591 	return 0;
5592 
5593 nla_put_failure:
5594 	return -EMSGSIZE;
5595 }
5596 
5597 static size_t inet6_get_link_af_size(const struct net_device *dev,
5598 				     u32 ext_filter_mask)
5599 {
5600 	if (!__in6_dev_get(dev))
5601 		return 0;
5602 
5603 	return inet6_ifla6_size();
5604 }
5605 
5606 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5607 			      u32 ext_filter_mask)
5608 {
5609 	struct inet6_dev *idev = __in6_dev_get(dev);
5610 
5611 	if (!idev)
5612 		return -ENODATA;
5613 
5614 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5615 		return -EMSGSIZE;
5616 
5617 	return 0;
5618 }
5619 
5620 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
5621 {
5622 	struct inet6_ifaddr *ifp;
5623 	struct net_device *dev = idev->dev;
5624 	bool clear_token, update_rs = false;
5625 	struct in6_addr ll_addr;
5626 
5627 	ASSERT_RTNL();
5628 
5629 	if (!token)
5630 		return -EINVAL;
5631 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
5632 		return -EINVAL;
5633 	if (!ipv6_accept_ra(idev))
5634 		return -EINVAL;
5635 	if (idev->cnf.rtr_solicits == 0)
5636 		return -EINVAL;
5637 
5638 	write_lock_bh(&idev->lock);
5639 
5640 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5641 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5642 
5643 	write_unlock_bh(&idev->lock);
5644 
5645 	clear_token = ipv6_addr_any(token);
5646 	if (clear_token)
5647 		goto update_lft;
5648 
5649 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5650 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5651 			     IFA_F_OPTIMISTIC)) {
5652 		/* If we're not ready, then normal ifup will take care
5653 		 * of this. Otherwise, we need to request our rs here.
5654 		 */
5655 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5656 		update_rs = true;
5657 	}
5658 
5659 update_lft:
5660 	write_lock_bh(&idev->lock);
5661 
5662 	if (update_rs) {
5663 		idev->if_flags |= IF_RS_SENT;
5664 		idev->rs_interval = rfc3315_s14_backoff_init(
5665 			idev->cnf.rtr_solicit_interval);
5666 		idev->rs_probes = 1;
5667 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5668 	}
5669 
5670 	/* Well, that's kinda nasty ... */
5671 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5672 		spin_lock(&ifp->lock);
5673 		if (ifp->tokenized) {
5674 			ifp->valid_lft = 0;
5675 			ifp->prefered_lft = 0;
5676 		}
5677 		spin_unlock(&ifp->lock);
5678 	}
5679 
5680 	write_unlock_bh(&idev->lock);
5681 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5682 	addrconf_verify_rtnl();
5683 	return 0;
5684 }
5685 
5686 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5687 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5688 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5689 };
5690 
5691 static int check_addr_gen_mode(int mode)
5692 {
5693 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5694 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5695 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5696 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5697 		return -EINVAL;
5698 	return 1;
5699 }
5700 
5701 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5702 				int mode)
5703 {
5704 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5705 	    !idev->cnf.stable_secret.initialized &&
5706 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5707 		return -EINVAL;
5708 	return 1;
5709 }
5710 
5711 static int inet6_validate_link_af(const struct net_device *dev,
5712 				  const struct nlattr *nla)
5713 {
5714 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5715 	struct inet6_dev *idev = NULL;
5716 	int err;
5717 
5718 	if (dev) {
5719 		idev = __in6_dev_get(dev);
5720 		if (!idev)
5721 			return -EAFNOSUPPORT;
5722 	}
5723 
5724 	err = nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla,
5725 					  inet6_af_policy, NULL);
5726 	if (err)
5727 		return err;
5728 
5729 	if (!tb[IFLA_INET6_TOKEN] && !tb[IFLA_INET6_ADDR_GEN_MODE])
5730 		return -EINVAL;
5731 
5732 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5733 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5734 
5735 		if (check_addr_gen_mode(mode) < 0)
5736 			return -EINVAL;
5737 		if (dev && check_stable_privacy(idev, dev_net(dev), mode) < 0)
5738 			return -EINVAL;
5739 	}
5740 
5741 	return 0;
5742 }
5743 
5744 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
5745 {
5746 	struct inet6_dev *idev = __in6_dev_get(dev);
5747 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5748 	int err;
5749 
5750 	if (!idev)
5751 		return -EAFNOSUPPORT;
5752 
5753 	if (nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
5754 		BUG();
5755 
5756 	if (tb[IFLA_INET6_TOKEN]) {
5757 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
5758 		if (err)
5759 			return err;
5760 	}
5761 
5762 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5763 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5764 
5765 		idev->cnf.addr_gen_mode = mode;
5766 	}
5767 
5768 	return 0;
5769 }
5770 
5771 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
5772 			     u32 portid, u32 seq, int event, unsigned int flags)
5773 {
5774 	struct net_device *dev = idev->dev;
5775 	struct ifinfomsg *hdr;
5776 	struct nlmsghdr *nlh;
5777 	void *protoinfo;
5778 
5779 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
5780 	if (!nlh)
5781 		return -EMSGSIZE;
5782 
5783 	hdr = nlmsg_data(nlh);
5784 	hdr->ifi_family = AF_INET6;
5785 	hdr->__ifi_pad = 0;
5786 	hdr->ifi_type = dev->type;
5787 	hdr->ifi_index = dev->ifindex;
5788 	hdr->ifi_flags = dev_get_flags(dev);
5789 	hdr->ifi_change = 0;
5790 
5791 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
5792 	    (dev->addr_len &&
5793 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
5794 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
5795 	    (dev->ifindex != dev_get_iflink(dev) &&
5796 	     nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))) ||
5797 	    nla_put_u8(skb, IFLA_OPERSTATE,
5798 		       netif_running(dev) ? dev->operstate : IF_OPER_DOWN))
5799 		goto nla_put_failure;
5800 	protoinfo = nla_nest_start_noflag(skb, IFLA_PROTINFO);
5801 	if (!protoinfo)
5802 		goto nla_put_failure;
5803 
5804 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
5805 		goto nla_put_failure;
5806 
5807 	nla_nest_end(skb, protoinfo);
5808 	nlmsg_end(skb, nlh);
5809 	return 0;
5810 
5811 nla_put_failure:
5812 	nlmsg_cancel(skb, nlh);
5813 	return -EMSGSIZE;
5814 }
5815 
5816 static int inet6_valid_dump_ifinfo(const struct nlmsghdr *nlh,
5817 				   struct netlink_ext_ack *extack)
5818 {
5819 	struct ifinfomsg *ifm;
5820 
5821 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5822 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for link dump request");
5823 		return -EINVAL;
5824 	}
5825 
5826 	if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
5827 		NL_SET_ERR_MSG_MOD(extack, "Invalid data after header");
5828 		return -EINVAL;
5829 	}
5830 
5831 	ifm = nlmsg_data(nlh);
5832 	if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
5833 	    ifm->ifi_change || ifm->ifi_index) {
5834 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for dump request");
5835 		return -EINVAL;
5836 	}
5837 
5838 	return 0;
5839 }
5840 
5841 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
5842 {
5843 	struct net *net = sock_net(skb->sk);
5844 	int h, s_h;
5845 	int idx = 0, s_idx;
5846 	struct net_device *dev;
5847 	struct inet6_dev *idev;
5848 	struct hlist_head *head;
5849 
5850 	/* only requests using strict checking can pass data to
5851 	 * influence the dump
5852 	 */
5853 	if (cb->strict_check) {
5854 		int err = inet6_valid_dump_ifinfo(cb->nlh, cb->extack);
5855 
5856 		if (err < 0)
5857 			return err;
5858 	}
5859 
5860 	s_h = cb->args[0];
5861 	s_idx = cb->args[1];
5862 
5863 	rcu_read_lock();
5864 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5865 		idx = 0;
5866 		head = &net->dev_index_head[h];
5867 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5868 			if (idx < s_idx)
5869 				goto cont;
5870 			idev = __in6_dev_get(dev);
5871 			if (!idev)
5872 				goto cont;
5873 			if (inet6_fill_ifinfo(skb, idev,
5874 					      NETLINK_CB(cb->skb).portid,
5875 					      cb->nlh->nlmsg_seq,
5876 					      RTM_NEWLINK, NLM_F_MULTI) < 0)
5877 				goto out;
5878 cont:
5879 			idx++;
5880 		}
5881 	}
5882 out:
5883 	rcu_read_unlock();
5884 	cb->args[1] = idx;
5885 	cb->args[0] = h;
5886 
5887 	return skb->len;
5888 }
5889 
5890 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
5891 {
5892 	struct sk_buff *skb;
5893 	struct net *net = dev_net(idev->dev);
5894 	int err = -ENOBUFS;
5895 
5896 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
5897 	if (!skb)
5898 		goto errout;
5899 
5900 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
5901 	if (err < 0) {
5902 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
5903 		WARN_ON(err == -EMSGSIZE);
5904 		kfree_skb(skb);
5905 		goto errout;
5906 	}
5907 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
5908 	return;
5909 errout:
5910 	if (err < 0)
5911 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
5912 }
5913 
5914 static inline size_t inet6_prefix_nlmsg_size(void)
5915 {
5916 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
5917 	       + nla_total_size(sizeof(struct in6_addr))
5918 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
5919 }
5920 
5921 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
5922 			     struct prefix_info *pinfo, u32 portid, u32 seq,
5923 			     int event, unsigned int flags)
5924 {
5925 	struct prefixmsg *pmsg;
5926 	struct nlmsghdr *nlh;
5927 	struct prefix_cacheinfo	ci;
5928 
5929 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
5930 	if (!nlh)
5931 		return -EMSGSIZE;
5932 
5933 	pmsg = nlmsg_data(nlh);
5934 	pmsg->prefix_family = AF_INET6;
5935 	pmsg->prefix_pad1 = 0;
5936 	pmsg->prefix_pad2 = 0;
5937 	pmsg->prefix_ifindex = idev->dev->ifindex;
5938 	pmsg->prefix_len = pinfo->prefix_len;
5939 	pmsg->prefix_type = pinfo->type;
5940 	pmsg->prefix_pad3 = 0;
5941 	pmsg->prefix_flags = 0;
5942 	if (pinfo->onlink)
5943 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
5944 	if (pinfo->autoconf)
5945 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
5946 
5947 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
5948 		goto nla_put_failure;
5949 	ci.preferred_time = ntohl(pinfo->prefered);
5950 	ci.valid_time = ntohl(pinfo->valid);
5951 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
5952 		goto nla_put_failure;
5953 	nlmsg_end(skb, nlh);
5954 	return 0;
5955 
5956 nla_put_failure:
5957 	nlmsg_cancel(skb, nlh);
5958 	return -EMSGSIZE;
5959 }
5960 
5961 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
5962 			 struct prefix_info *pinfo)
5963 {
5964 	struct sk_buff *skb;
5965 	struct net *net = dev_net(idev->dev);
5966 	int err = -ENOBUFS;
5967 
5968 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
5969 	if (!skb)
5970 		goto errout;
5971 
5972 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
5973 	if (err < 0) {
5974 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
5975 		WARN_ON(err == -EMSGSIZE);
5976 		kfree_skb(skb);
5977 		goto errout;
5978 	}
5979 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
5980 	return;
5981 errout:
5982 	if (err < 0)
5983 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
5984 }
5985 
5986 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5987 {
5988 	struct net *net = dev_net(ifp->idev->dev);
5989 
5990 	if (event)
5991 		ASSERT_RTNL();
5992 
5993 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
5994 
5995 	switch (event) {
5996 	case RTM_NEWADDR:
5997 		/*
5998 		 * If the address was optimistic we inserted the route at the
5999 		 * start of our DAD process, so we don't need to do it again.
6000 		 * If the device was taken down in the middle of the DAD
6001 		 * cycle there is a race where we could get here without a
6002 		 * host route, so nothing to insert. That will be fixed when
6003 		 * the device is brought up.
6004 		 */
6005 		if (ifp->rt && !rcu_access_pointer(ifp->rt->fib6_node)) {
6006 			ip6_ins_rt(net, ifp->rt);
6007 		} else if (!ifp->rt && (ifp->idev->dev->flags & IFF_UP)) {
6008 			pr_warn("BUG: Address %pI6c on device %s is missing its host route.\n",
6009 				&ifp->addr, ifp->idev->dev->name);
6010 		}
6011 
6012 		if (ifp->idev->cnf.forwarding)
6013 			addrconf_join_anycast(ifp);
6014 		if (!ipv6_addr_any(&ifp->peer_addr))
6015 			addrconf_prefix_route(&ifp->peer_addr, 128,
6016 					      ifp->rt_priority, ifp->idev->dev,
6017 					      0, 0, GFP_ATOMIC);
6018 		break;
6019 	case RTM_DELADDR:
6020 		if (ifp->idev->cnf.forwarding)
6021 			addrconf_leave_anycast(ifp);
6022 		addrconf_leave_solict(ifp->idev, &ifp->addr);
6023 		if (!ipv6_addr_any(&ifp->peer_addr)) {
6024 			struct fib6_info *rt;
6025 
6026 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
6027 						       ifp->idev->dev, 0, 0,
6028 						       false);
6029 			if (rt)
6030 				ip6_del_rt(net, rt);
6031 		}
6032 		if (ifp->rt) {
6033 			ip6_del_rt(net, ifp->rt);
6034 			ifp->rt = NULL;
6035 		}
6036 		rt_genid_bump_ipv6(net);
6037 		break;
6038 	}
6039 	atomic_inc(&net->ipv6.dev_addr_genid);
6040 }
6041 
6042 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6043 {
6044 	rcu_read_lock_bh();
6045 	if (likely(ifp->idev->dead == 0))
6046 		__ipv6_ifa_notify(event, ifp);
6047 	rcu_read_unlock_bh();
6048 }
6049 
6050 #ifdef CONFIG_SYSCTL
6051 
6052 static
6053 int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
6054 			   void __user *buffer, size_t *lenp, loff_t *ppos)
6055 {
6056 	int *valp = ctl->data;
6057 	int val = *valp;
6058 	loff_t pos = *ppos;
6059 	struct ctl_table lctl;
6060 	int ret;
6061 
6062 	/*
6063 	 * ctl->data points to idev->cnf.forwarding, we should
6064 	 * not modify it until we get the rtnl lock.
6065 	 */
6066 	lctl = *ctl;
6067 	lctl.data = &val;
6068 
6069 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6070 
6071 	if (write)
6072 		ret = addrconf_fixup_forwarding(ctl, valp, val);
6073 	if (ret)
6074 		*ppos = pos;
6075 	return ret;
6076 }
6077 
6078 static
6079 int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
6080 			void __user *buffer, size_t *lenp, loff_t *ppos)
6081 {
6082 	struct inet6_dev *idev = ctl->extra1;
6083 	int min_mtu = IPV6_MIN_MTU;
6084 	struct ctl_table lctl;
6085 
6086 	lctl = *ctl;
6087 	lctl.extra1 = &min_mtu;
6088 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
6089 
6090 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
6091 }
6092 
6093 static void dev_disable_change(struct inet6_dev *idev)
6094 {
6095 	struct netdev_notifier_info info;
6096 
6097 	if (!idev || !idev->dev)
6098 		return;
6099 
6100 	netdev_notifier_info_init(&info, idev->dev);
6101 	if (idev->cnf.disable_ipv6)
6102 		addrconf_notify(NULL, NETDEV_DOWN, &info);
6103 	else
6104 		addrconf_notify(NULL, NETDEV_UP, &info);
6105 }
6106 
6107 static void addrconf_disable_change(struct net *net, __s32 newf)
6108 {
6109 	struct net_device *dev;
6110 	struct inet6_dev *idev;
6111 
6112 	for_each_netdev(net, dev) {
6113 		idev = __in6_dev_get(dev);
6114 		if (idev) {
6115 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
6116 			idev->cnf.disable_ipv6 = newf;
6117 			if (changed)
6118 				dev_disable_change(idev);
6119 		}
6120 	}
6121 }
6122 
6123 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
6124 {
6125 	struct net *net;
6126 	int old;
6127 
6128 	if (!rtnl_trylock())
6129 		return restart_syscall();
6130 
6131 	net = (struct net *)table->extra2;
6132 	old = *p;
6133 	*p = newf;
6134 
6135 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
6136 		rtnl_unlock();
6137 		return 0;
6138 	}
6139 
6140 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
6141 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
6142 		addrconf_disable_change(net, newf);
6143 	} else if ((!newf) ^ (!old))
6144 		dev_disable_change((struct inet6_dev *)table->extra1);
6145 
6146 	rtnl_unlock();
6147 	return 0;
6148 }
6149 
6150 static
6151 int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
6152 			    void __user *buffer, size_t *lenp, loff_t *ppos)
6153 {
6154 	int *valp = ctl->data;
6155 	int val = *valp;
6156 	loff_t pos = *ppos;
6157 	struct ctl_table lctl;
6158 	int ret;
6159 
6160 	/*
6161 	 * ctl->data points to idev->cnf.disable_ipv6, we should
6162 	 * not modify it until we get the rtnl lock.
6163 	 */
6164 	lctl = *ctl;
6165 	lctl.data = &val;
6166 
6167 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6168 
6169 	if (write)
6170 		ret = addrconf_disable_ipv6(ctl, valp, val);
6171 	if (ret)
6172 		*ppos = pos;
6173 	return ret;
6174 }
6175 
6176 static
6177 int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
6178 			      void __user *buffer, size_t *lenp, loff_t *ppos)
6179 {
6180 	int *valp = ctl->data;
6181 	int ret;
6182 	int old, new;
6183 
6184 	old = *valp;
6185 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
6186 	new = *valp;
6187 
6188 	if (write && old != new) {
6189 		struct net *net = ctl->extra2;
6190 
6191 		if (!rtnl_trylock())
6192 			return restart_syscall();
6193 
6194 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
6195 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6196 						     NETCONFA_PROXY_NEIGH,
6197 						     NETCONFA_IFINDEX_DEFAULT,
6198 						     net->ipv6.devconf_dflt);
6199 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
6200 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6201 						     NETCONFA_PROXY_NEIGH,
6202 						     NETCONFA_IFINDEX_ALL,
6203 						     net->ipv6.devconf_all);
6204 		else {
6205 			struct inet6_dev *idev = ctl->extra1;
6206 
6207 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6208 						     NETCONFA_PROXY_NEIGH,
6209 						     idev->dev->ifindex,
6210 						     &idev->cnf);
6211 		}
6212 		rtnl_unlock();
6213 	}
6214 
6215 	return ret;
6216 }
6217 
6218 static int addrconf_sysctl_addr_gen_mode(struct ctl_table *ctl, int write,
6219 					 void __user *buffer, size_t *lenp,
6220 					 loff_t *ppos)
6221 {
6222 	int ret = 0;
6223 	u32 new_val;
6224 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
6225 	struct net *net = (struct net *)ctl->extra2;
6226 	struct ctl_table tmp = {
6227 		.data = &new_val,
6228 		.maxlen = sizeof(new_val),
6229 		.mode = ctl->mode,
6230 	};
6231 
6232 	if (!rtnl_trylock())
6233 		return restart_syscall();
6234 
6235 	new_val = *((u32 *)ctl->data);
6236 
6237 	ret = proc_douintvec(&tmp, write, buffer, lenp, ppos);
6238 	if (ret != 0)
6239 		goto out;
6240 
6241 	if (write) {
6242 		if (check_addr_gen_mode(new_val) < 0) {
6243 			ret = -EINVAL;
6244 			goto out;
6245 		}
6246 
6247 		if (idev) {
6248 			if (check_stable_privacy(idev, net, new_val) < 0) {
6249 				ret = -EINVAL;
6250 				goto out;
6251 			}
6252 
6253 			if (idev->cnf.addr_gen_mode != new_val) {
6254 				idev->cnf.addr_gen_mode = new_val;
6255 				addrconf_dev_config(idev->dev);
6256 			}
6257 		} else if (&net->ipv6.devconf_all->addr_gen_mode == ctl->data) {
6258 			struct net_device *dev;
6259 
6260 			net->ipv6.devconf_dflt->addr_gen_mode = new_val;
6261 			for_each_netdev(net, dev) {
6262 				idev = __in6_dev_get(dev);
6263 				if (idev &&
6264 				    idev->cnf.addr_gen_mode != new_val) {
6265 					idev->cnf.addr_gen_mode = new_val;
6266 					addrconf_dev_config(idev->dev);
6267 				}
6268 			}
6269 		}
6270 
6271 		*((u32 *)ctl->data) = new_val;
6272 	}
6273 
6274 out:
6275 	rtnl_unlock();
6276 
6277 	return ret;
6278 }
6279 
6280 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
6281 					 void __user *buffer, size_t *lenp,
6282 					 loff_t *ppos)
6283 {
6284 	int err;
6285 	struct in6_addr addr;
6286 	char str[IPV6_MAX_STRLEN];
6287 	struct ctl_table lctl = *ctl;
6288 	struct net *net = ctl->extra2;
6289 	struct ipv6_stable_secret *secret = ctl->data;
6290 
6291 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
6292 		return -EIO;
6293 
6294 	lctl.maxlen = IPV6_MAX_STRLEN;
6295 	lctl.data = str;
6296 
6297 	if (!rtnl_trylock())
6298 		return restart_syscall();
6299 
6300 	if (!write && !secret->initialized) {
6301 		err = -EIO;
6302 		goto out;
6303 	}
6304 
6305 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
6306 	if (err >= sizeof(str)) {
6307 		err = -EIO;
6308 		goto out;
6309 	}
6310 
6311 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
6312 	if (err || !write)
6313 		goto out;
6314 
6315 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
6316 		err = -EIO;
6317 		goto out;
6318 	}
6319 
6320 	secret->initialized = true;
6321 	secret->secret = addr;
6322 
6323 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
6324 		struct net_device *dev;
6325 
6326 		for_each_netdev(net, dev) {
6327 			struct inet6_dev *idev = __in6_dev_get(dev);
6328 
6329 			if (idev) {
6330 				idev->cnf.addr_gen_mode =
6331 					IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6332 			}
6333 		}
6334 	} else {
6335 		struct inet6_dev *idev = ctl->extra1;
6336 
6337 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6338 	}
6339 
6340 out:
6341 	rtnl_unlock();
6342 
6343 	return err;
6344 }
6345 
6346 static
6347 int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
6348 						int write,
6349 						void __user *buffer,
6350 						size_t *lenp,
6351 						loff_t *ppos)
6352 {
6353 	int *valp = ctl->data;
6354 	int val = *valp;
6355 	loff_t pos = *ppos;
6356 	struct ctl_table lctl;
6357 	int ret;
6358 
6359 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
6360 	 * we should not modify it until we get the rtnl lock.
6361 	 */
6362 	lctl = *ctl;
6363 	lctl.data = &val;
6364 
6365 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6366 
6367 	if (write)
6368 		ret = addrconf_fixup_linkdown(ctl, valp, val);
6369 	if (ret)
6370 		*ppos = pos;
6371 	return ret;
6372 }
6373 
6374 static
6375 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
6376 {
6377 	if (rt) {
6378 		if (action)
6379 			rt->dst.flags |= DST_NOPOLICY;
6380 		else
6381 			rt->dst.flags &= ~DST_NOPOLICY;
6382 	}
6383 }
6384 
6385 static
6386 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
6387 {
6388 	struct inet6_ifaddr *ifa;
6389 
6390 	read_lock_bh(&idev->lock);
6391 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
6392 		spin_lock(&ifa->lock);
6393 		if (ifa->rt) {
6394 			/* host routes only use builtin fib6_nh */
6395 			struct fib6_nh *nh = ifa->rt->fib6_nh;
6396 			int cpu;
6397 
6398 			rcu_read_lock();
6399 			ifa->rt->dst_nopolicy = val ? true : false;
6400 			if (nh->rt6i_pcpu) {
6401 				for_each_possible_cpu(cpu) {
6402 					struct rt6_info **rtp;
6403 
6404 					rtp = per_cpu_ptr(nh->rt6i_pcpu, cpu);
6405 					addrconf_set_nopolicy(*rtp, val);
6406 				}
6407 			}
6408 			rcu_read_unlock();
6409 		}
6410 		spin_unlock(&ifa->lock);
6411 	}
6412 	read_unlock_bh(&idev->lock);
6413 }
6414 
6415 static
6416 int addrconf_disable_policy(struct ctl_table *ctl, int *valp, int val)
6417 {
6418 	struct inet6_dev *idev;
6419 	struct net *net;
6420 
6421 	if (!rtnl_trylock())
6422 		return restart_syscall();
6423 
6424 	*valp = val;
6425 
6426 	net = (struct net *)ctl->extra2;
6427 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
6428 		rtnl_unlock();
6429 		return 0;
6430 	}
6431 
6432 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
6433 		struct net_device *dev;
6434 
6435 		for_each_netdev(net, dev) {
6436 			idev = __in6_dev_get(dev);
6437 			if (idev)
6438 				addrconf_disable_policy_idev(idev, val);
6439 		}
6440 	} else {
6441 		idev = (struct inet6_dev *)ctl->extra1;
6442 		addrconf_disable_policy_idev(idev, val);
6443 	}
6444 
6445 	rtnl_unlock();
6446 	return 0;
6447 }
6448 
6449 static
6450 int addrconf_sysctl_disable_policy(struct ctl_table *ctl, int write,
6451 				   void __user *buffer, size_t *lenp,
6452 				   loff_t *ppos)
6453 {
6454 	int *valp = ctl->data;
6455 	int val = *valp;
6456 	loff_t pos = *ppos;
6457 	struct ctl_table lctl;
6458 	int ret;
6459 
6460 	lctl = *ctl;
6461 	lctl.data = &val;
6462 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6463 
6464 	if (write && (*valp != val))
6465 		ret = addrconf_disable_policy(ctl, valp, val);
6466 
6467 	if (ret)
6468 		*ppos = pos;
6469 
6470 	return ret;
6471 }
6472 
6473 static int minus_one = -1;
6474 static const int two_five_five = 255;
6475 
6476 static const struct ctl_table addrconf_sysctl[] = {
6477 	{
6478 		.procname	= "forwarding",
6479 		.data		= &ipv6_devconf.forwarding,
6480 		.maxlen		= sizeof(int),
6481 		.mode		= 0644,
6482 		.proc_handler	= addrconf_sysctl_forward,
6483 	},
6484 	{
6485 		.procname	= "hop_limit",
6486 		.data		= &ipv6_devconf.hop_limit,
6487 		.maxlen		= sizeof(int),
6488 		.mode		= 0644,
6489 		.proc_handler	= proc_dointvec_minmax,
6490 		.extra1		= (void *)SYSCTL_ONE,
6491 		.extra2		= (void *)&two_five_five,
6492 	},
6493 	{
6494 		.procname	= "mtu",
6495 		.data		= &ipv6_devconf.mtu6,
6496 		.maxlen		= sizeof(int),
6497 		.mode		= 0644,
6498 		.proc_handler	= addrconf_sysctl_mtu,
6499 	},
6500 	{
6501 		.procname	= "accept_ra",
6502 		.data		= &ipv6_devconf.accept_ra,
6503 		.maxlen		= sizeof(int),
6504 		.mode		= 0644,
6505 		.proc_handler	= proc_dointvec,
6506 	},
6507 	{
6508 		.procname	= "accept_redirects",
6509 		.data		= &ipv6_devconf.accept_redirects,
6510 		.maxlen		= sizeof(int),
6511 		.mode		= 0644,
6512 		.proc_handler	= proc_dointvec,
6513 	},
6514 	{
6515 		.procname	= "autoconf",
6516 		.data		= &ipv6_devconf.autoconf,
6517 		.maxlen		= sizeof(int),
6518 		.mode		= 0644,
6519 		.proc_handler	= proc_dointvec,
6520 	},
6521 	{
6522 		.procname	= "dad_transmits",
6523 		.data		= &ipv6_devconf.dad_transmits,
6524 		.maxlen		= sizeof(int),
6525 		.mode		= 0644,
6526 		.proc_handler	= proc_dointvec,
6527 	},
6528 	{
6529 		.procname	= "router_solicitations",
6530 		.data		= &ipv6_devconf.rtr_solicits,
6531 		.maxlen		= sizeof(int),
6532 		.mode		= 0644,
6533 		.proc_handler	= proc_dointvec_minmax,
6534 		.extra1		= &minus_one,
6535 	},
6536 	{
6537 		.procname	= "router_solicitation_interval",
6538 		.data		= &ipv6_devconf.rtr_solicit_interval,
6539 		.maxlen		= sizeof(int),
6540 		.mode		= 0644,
6541 		.proc_handler	= proc_dointvec_jiffies,
6542 	},
6543 	{
6544 		.procname	= "router_solicitation_max_interval",
6545 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6546 		.maxlen		= sizeof(int),
6547 		.mode		= 0644,
6548 		.proc_handler	= proc_dointvec_jiffies,
6549 	},
6550 	{
6551 		.procname	= "router_solicitation_delay",
6552 		.data		= &ipv6_devconf.rtr_solicit_delay,
6553 		.maxlen		= sizeof(int),
6554 		.mode		= 0644,
6555 		.proc_handler	= proc_dointvec_jiffies,
6556 	},
6557 	{
6558 		.procname	= "force_mld_version",
6559 		.data		= &ipv6_devconf.force_mld_version,
6560 		.maxlen		= sizeof(int),
6561 		.mode		= 0644,
6562 		.proc_handler	= proc_dointvec,
6563 	},
6564 	{
6565 		.procname	= "mldv1_unsolicited_report_interval",
6566 		.data		=
6567 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6568 		.maxlen		= sizeof(int),
6569 		.mode		= 0644,
6570 		.proc_handler	= proc_dointvec_ms_jiffies,
6571 	},
6572 	{
6573 		.procname	= "mldv2_unsolicited_report_interval",
6574 		.data		=
6575 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6576 		.maxlen		= sizeof(int),
6577 		.mode		= 0644,
6578 		.proc_handler	= proc_dointvec_ms_jiffies,
6579 	},
6580 	{
6581 		.procname	= "use_tempaddr",
6582 		.data		= &ipv6_devconf.use_tempaddr,
6583 		.maxlen		= sizeof(int),
6584 		.mode		= 0644,
6585 		.proc_handler	= proc_dointvec,
6586 	},
6587 	{
6588 		.procname	= "temp_valid_lft",
6589 		.data		= &ipv6_devconf.temp_valid_lft,
6590 		.maxlen		= sizeof(int),
6591 		.mode		= 0644,
6592 		.proc_handler	= proc_dointvec,
6593 	},
6594 	{
6595 		.procname	= "temp_prefered_lft",
6596 		.data		= &ipv6_devconf.temp_prefered_lft,
6597 		.maxlen		= sizeof(int),
6598 		.mode		= 0644,
6599 		.proc_handler	= proc_dointvec,
6600 	},
6601 	{
6602 		.procname	= "regen_max_retry",
6603 		.data		= &ipv6_devconf.regen_max_retry,
6604 		.maxlen		= sizeof(int),
6605 		.mode		= 0644,
6606 		.proc_handler	= proc_dointvec,
6607 	},
6608 	{
6609 		.procname	= "max_desync_factor",
6610 		.data		= &ipv6_devconf.max_desync_factor,
6611 		.maxlen		= sizeof(int),
6612 		.mode		= 0644,
6613 		.proc_handler	= proc_dointvec,
6614 	},
6615 	{
6616 		.procname	= "max_addresses",
6617 		.data		= &ipv6_devconf.max_addresses,
6618 		.maxlen		= sizeof(int),
6619 		.mode		= 0644,
6620 		.proc_handler	= proc_dointvec,
6621 	},
6622 	{
6623 		.procname	= "accept_ra_defrtr",
6624 		.data		= &ipv6_devconf.accept_ra_defrtr,
6625 		.maxlen		= sizeof(int),
6626 		.mode		= 0644,
6627 		.proc_handler	= proc_dointvec,
6628 	},
6629 	{
6630 		.procname	= "accept_ra_min_hop_limit",
6631 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6632 		.maxlen		= sizeof(int),
6633 		.mode		= 0644,
6634 		.proc_handler	= proc_dointvec,
6635 	},
6636 	{
6637 		.procname	= "accept_ra_pinfo",
6638 		.data		= &ipv6_devconf.accept_ra_pinfo,
6639 		.maxlen		= sizeof(int),
6640 		.mode		= 0644,
6641 		.proc_handler	= proc_dointvec,
6642 	},
6643 #ifdef CONFIG_IPV6_ROUTER_PREF
6644 	{
6645 		.procname	= "accept_ra_rtr_pref",
6646 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6647 		.maxlen		= sizeof(int),
6648 		.mode		= 0644,
6649 		.proc_handler	= proc_dointvec,
6650 	},
6651 	{
6652 		.procname	= "router_probe_interval",
6653 		.data		= &ipv6_devconf.rtr_probe_interval,
6654 		.maxlen		= sizeof(int),
6655 		.mode		= 0644,
6656 		.proc_handler	= proc_dointvec_jiffies,
6657 	},
6658 #ifdef CONFIG_IPV6_ROUTE_INFO
6659 	{
6660 		.procname	= "accept_ra_rt_info_min_plen",
6661 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6662 		.maxlen		= sizeof(int),
6663 		.mode		= 0644,
6664 		.proc_handler	= proc_dointvec,
6665 	},
6666 	{
6667 		.procname	= "accept_ra_rt_info_max_plen",
6668 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6669 		.maxlen		= sizeof(int),
6670 		.mode		= 0644,
6671 		.proc_handler	= proc_dointvec,
6672 	},
6673 #endif
6674 #endif
6675 	{
6676 		.procname	= "proxy_ndp",
6677 		.data		= &ipv6_devconf.proxy_ndp,
6678 		.maxlen		= sizeof(int),
6679 		.mode		= 0644,
6680 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6681 	},
6682 	{
6683 		.procname	= "accept_source_route",
6684 		.data		= &ipv6_devconf.accept_source_route,
6685 		.maxlen		= sizeof(int),
6686 		.mode		= 0644,
6687 		.proc_handler	= proc_dointvec,
6688 	},
6689 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
6690 	{
6691 		.procname	= "optimistic_dad",
6692 		.data		= &ipv6_devconf.optimistic_dad,
6693 		.maxlen		= sizeof(int),
6694 		.mode		= 0644,
6695 		.proc_handler   = proc_dointvec,
6696 	},
6697 	{
6698 		.procname	= "use_optimistic",
6699 		.data		= &ipv6_devconf.use_optimistic,
6700 		.maxlen		= sizeof(int),
6701 		.mode		= 0644,
6702 		.proc_handler	= proc_dointvec,
6703 	},
6704 #endif
6705 #ifdef CONFIG_IPV6_MROUTE
6706 	{
6707 		.procname	= "mc_forwarding",
6708 		.data		= &ipv6_devconf.mc_forwarding,
6709 		.maxlen		= sizeof(int),
6710 		.mode		= 0444,
6711 		.proc_handler	= proc_dointvec,
6712 	},
6713 #endif
6714 	{
6715 		.procname	= "disable_ipv6",
6716 		.data		= &ipv6_devconf.disable_ipv6,
6717 		.maxlen		= sizeof(int),
6718 		.mode		= 0644,
6719 		.proc_handler	= addrconf_sysctl_disable,
6720 	},
6721 	{
6722 		.procname	= "accept_dad",
6723 		.data		= &ipv6_devconf.accept_dad,
6724 		.maxlen		= sizeof(int),
6725 		.mode		= 0644,
6726 		.proc_handler	= proc_dointvec,
6727 	},
6728 	{
6729 		.procname	= "force_tllao",
6730 		.data		= &ipv6_devconf.force_tllao,
6731 		.maxlen		= sizeof(int),
6732 		.mode		= 0644,
6733 		.proc_handler	= proc_dointvec
6734 	},
6735 	{
6736 		.procname	= "ndisc_notify",
6737 		.data		= &ipv6_devconf.ndisc_notify,
6738 		.maxlen		= sizeof(int),
6739 		.mode		= 0644,
6740 		.proc_handler	= proc_dointvec
6741 	},
6742 	{
6743 		.procname	= "suppress_frag_ndisc",
6744 		.data		= &ipv6_devconf.suppress_frag_ndisc,
6745 		.maxlen		= sizeof(int),
6746 		.mode		= 0644,
6747 		.proc_handler	= proc_dointvec
6748 	},
6749 	{
6750 		.procname	= "accept_ra_from_local",
6751 		.data		= &ipv6_devconf.accept_ra_from_local,
6752 		.maxlen		= sizeof(int),
6753 		.mode		= 0644,
6754 		.proc_handler	= proc_dointvec,
6755 	},
6756 	{
6757 		.procname	= "accept_ra_mtu",
6758 		.data		= &ipv6_devconf.accept_ra_mtu,
6759 		.maxlen		= sizeof(int),
6760 		.mode		= 0644,
6761 		.proc_handler	= proc_dointvec,
6762 	},
6763 	{
6764 		.procname	= "stable_secret",
6765 		.data		= &ipv6_devconf.stable_secret,
6766 		.maxlen		= IPV6_MAX_STRLEN,
6767 		.mode		= 0600,
6768 		.proc_handler	= addrconf_sysctl_stable_secret,
6769 	},
6770 	{
6771 		.procname	= "use_oif_addrs_only",
6772 		.data		= &ipv6_devconf.use_oif_addrs_only,
6773 		.maxlen		= sizeof(int),
6774 		.mode		= 0644,
6775 		.proc_handler	= proc_dointvec,
6776 	},
6777 	{
6778 		.procname	= "ignore_routes_with_linkdown",
6779 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
6780 		.maxlen		= sizeof(int),
6781 		.mode		= 0644,
6782 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
6783 	},
6784 	{
6785 		.procname	= "drop_unicast_in_l2_multicast",
6786 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
6787 		.maxlen		= sizeof(int),
6788 		.mode		= 0644,
6789 		.proc_handler	= proc_dointvec,
6790 	},
6791 	{
6792 		.procname	= "drop_unsolicited_na",
6793 		.data		= &ipv6_devconf.drop_unsolicited_na,
6794 		.maxlen		= sizeof(int),
6795 		.mode		= 0644,
6796 		.proc_handler	= proc_dointvec,
6797 	},
6798 	{
6799 		.procname	= "keep_addr_on_down",
6800 		.data		= &ipv6_devconf.keep_addr_on_down,
6801 		.maxlen		= sizeof(int),
6802 		.mode		= 0644,
6803 		.proc_handler	= proc_dointvec,
6804 
6805 	},
6806 	{
6807 		.procname	= "seg6_enabled",
6808 		.data		= &ipv6_devconf.seg6_enabled,
6809 		.maxlen		= sizeof(int),
6810 		.mode		= 0644,
6811 		.proc_handler	= proc_dointvec,
6812 	},
6813 #ifdef CONFIG_IPV6_SEG6_HMAC
6814 	{
6815 		.procname	= "seg6_require_hmac",
6816 		.data		= &ipv6_devconf.seg6_require_hmac,
6817 		.maxlen		= sizeof(int),
6818 		.mode		= 0644,
6819 		.proc_handler	= proc_dointvec,
6820 	},
6821 #endif
6822 	{
6823 		.procname       = "enhanced_dad",
6824 		.data           = &ipv6_devconf.enhanced_dad,
6825 		.maxlen         = sizeof(int),
6826 		.mode           = 0644,
6827 		.proc_handler   = proc_dointvec,
6828 	},
6829 	{
6830 		.procname		= "addr_gen_mode",
6831 		.data			= &ipv6_devconf.addr_gen_mode,
6832 		.maxlen			= sizeof(int),
6833 		.mode			= 0644,
6834 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
6835 	},
6836 	{
6837 		.procname       = "disable_policy",
6838 		.data           = &ipv6_devconf.disable_policy,
6839 		.maxlen         = sizeof(int),
6840 		.mode           = 0644,
6841 		.proc_handler   = addrconf_sysctl_disable_policy,
6842 	},
6843 	{
6844 		.procname	= "ndisc_tclass",
6845 		.data		= &ipv6_devconf.ndisc_tclass,
6846 		.maxlen		= sizeof(int),
6847 		.mode		= 0644,
6848 		.proc_handler	= proc_dointvec_minmax,
6849 		.extra1		= (void *)SYSCTL_ZERO,
6850 		.extra2		= (void *)&two_five_five,
6851 	},
6852 	{
6853 		/* sentinel */
6854 	}
6855 };
6856 
6857 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
6858 		struct inet6_dev *idev, struct ipv6_devconf *p)
6859 {
6860 	int i, ifindex;
6861 	struct ctl_table *table;
6862 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
6863 
6864 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL);
6865 	if (!table)
6866 		goto out;
6867 
6868 	for (i = 0; table[i].data; i++) {
6869 		table[i].data += (char *)p - (char *)&ipv6_devconf;
6870 		/* If one of these is already set, then it is not safe to
6871 		 * overwrite either of them: this makes proc_dointvec_minmax
6872 		 * usable.
6873 		 */
6874 		if (!table[i].extra1 && !table[i].extra2) {
6875 			table[i].extra1 = idev; /* embedded; no ref */
6876 			table[i].extra2 = net;
6877 		}
6878 	}
6879 
6880 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
6881 
6882 	p->sysctl_header = register_net_sysctl(net, path, table);
6883 	if (!p->sysctl_header)
6884 		goto free;
6885 
6886 	if (!strcmp(dev_name, "all"))
6887 		ifindex = NETCONFA_IFINDEX_ALL;
6888 	else if (!strcmp(dev_name, "default"))
6889 		ifindex = NETCONFA_IFINDEX_DEFAULT;
6890 	else
6891 		ifindex = idev->dev->ifindex;
6892 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
6893 				     ifindex, p);
6894 	return 0;
6895 
6896 free:
6897 	kfree(table);
6898 out:
6899 	return -ENOBUFS;
6900 }
6901 
6902 static void __addrconf_sysctl_unregister(struct net *net,
6903 					 struct ipv6_devconf *p, int ifindex)
6904 {
6905 	struct ctl_table *table;
6906 
6907 	if (!p->sysctl_header)
6908 		return;
6909 
6910 	table = p->sysctl_header->ctl_table_arg;
6911 	unregister_net_sysctl_table(p->sysctl_header);
6912 	p->sysctl_header = NULL;
6913 	kfree(table);
6914 
6915 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
6916 }
6917 
6918 static int addrconf_sysctl_register(struct inet6_dev *idev)
6919 {
6920 	int err;
6921 
6922 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
6923 		return -EINVAL;
6924 
6925 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
6926 				    &ndisc_ifinfo_sysctl_change);
6927 	if (err)
6928 		return err;
6929 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
6930 					 idev, &idev->cnf);
6931 	if (err)
6932 		neigh_sysctl_unregister(idev->nd_parms);
6933 
6934 	return err;
6935 }
6936 
6937 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
6938 {
6939 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
6940 				     idev->dev->ifindex);
6941 	neigh_sysctl_unregister(idev->nd_parms);
6942 }
6943 
6944 
6945 #endif
6946 
6947 static int __net_init addrconf_init_net(struct net *net)
6948 {
6949 	int err = -ENOMEM;
6950 	struct ipv6_devconf *all, *dflt;
6951 
6952 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
6953 	if (!all)
6954 		goto err_alloc_all;
6955 
6956 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
6957 	if (!dflt)
6958 		goto err_alloc_dflt;
6959 
6960 	if (IS_ENABLED(CONFIG_SYSCTL) &&
6961 	    sysctl_devconf_inherit_init_net == 1 && !net_eq(net, &init_net)) {
6962 		memcpy(all, init_net.ipv6.devconf_all, sizeof(ipv6_devconf));
6963 		memcpy(dflt, init_net.ipv6.devconf_dflt, sizeof(ipv6_devconf_dflt));
6964 	}
6965 
6966 	/* these will be inherited by all namespaces */
6967 	dflt->autoconf = ipv6_defaults.autoconf;
6968 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
6969 
6970 	dflt->stable_secret.initialized = false;
6971 	all->stable_secret.initialized = false;
6972 
6973 	net->ipv6.devconf_all = all;
6974 	net->ipv6.devconf_dflt = dflt;
6975 
6976 #ifdef CONFIG_SYSCTL
6977 	err = __addrconf_sysctl_register(net, "all", NULL, all);
6978 	if (err < 0)
6979 		goto err_reg_all;
6980 
6981 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
6982 	if (err < 0)
6983 		goto err_reg_dflt;
6984 #endif
6985 	return 0;
6986 
6987 #ifdef CONFIG_SYSCTL
6988 err_reg_dflt:
6989 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
6990 err_reg_all:
6991 	kfree(dflt);
6992 #endif
6993 err_alloc_dflt:
6994 	kfree(all);
6995 err_alloc_all:
6996 	return err;
6997 }
6998 
6999 static void __net_exit addrconf_exit_net(struct net *net)
7000 {
7001 #ifdef CONFIG_SYSCTL
7002 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
7003 				     NETCONFA_IFINDEX_DEFAULT);
7004 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
7005 				     NETCONFA_IFINDEX_ALL);
7006 #endif
7007 	kfree(net->ipv6.devconf_dflt);
7008 	kfree(net->ipv6.devconf_all);
7009 }
7010 
7011 static struct pernet_operations addrconf_ops = {
7012 	.init = addrconf_init_net,
7013 	.exit = addrconf_exit_net,
7014 };
7015 
7016 static struct rtnl_af_ops inet6_ops __read_mostly = {
7017 	.family		  = AF_INET6,
7018 	.fill_link_af	  = inet6_fill_link_af,
7019 	.get_link_af_size = inet6_get_link_af_size,
7020 	.validate_link_af = inet6_validate_link_af,
7021 	.set_link_af	  = inet6_set_link_af,
7022 };
7023 
7024 /*
7025  *	Init / cleanup code
7026  */
7027 
7028 int __init addrconf_init(void)
7029 {
7030 	struct inet6_dev *idev;
7031 	int i, err;
7032 
7033 	err = ipv6_addr_label_init();
7034 	if (err < 0) {
7035 		pr_crit("%s: cannot initialize default policy table: %d\n",
7036 			__func__, err);
7037 		goto out;
7038 	}
7039 
7040 	err = register_pernet_subsys(&addrconf_ops);
7041 	if (err < 0)
7042 		goto out_addrlabel;
7043 
7044 	addrconf_wq = create_workqueue("ipv6_addrconf");
7045 	if (!addrconf_wq) {
7046 		err = -ENOMEM;
7047 		goto out_nowq;
7048 	}
7049 
7050 	/* The addrconf netdev notifier requires that loopback_dev
7051 	 * has it's ipv6 private information allocated and setup
7052 	 * before it can bring up and give link-local addresses
7053 	 * to other devices which are up.
7054 	 *
7055 	 * Unfortunately, loopback_dev is not necessarily the first
7056 	 * entry in the global dev_base list of net devices.  In fact,
7057 	 * it is likely to be the very last entry on that list.
7058 	 * So this causes the notifier registry below to try and
7059 	 * give link-local addresses to all devices besides loopback_dev
7060 	 * first, then loopback_dev, which cases all the non-loopback_dev
7061 	 * devices to fail to get a link-local address.
7062 	 *
7063 	 * So, as a temporary fix, allocate the ipv6 structure for
7064 	 * loopback_dev first by hand.
7065 	 * Longer term, all of the dependencies ipv6 has upon the loopback
7066 	 * device and it being up should be removed.
7067 	 */
7068 	rtnl_lock();
7069 	idev = ipv6_add_dev(init_net.loopback_dev);
7070 	rtnl_unlock();
7071 	if (IS_ERR(idev)) {
7072 		err = PTR_ERR(idev);
7073 		goto errlo;
7074 	}
7075 
7076 	ip6_route_init_special_entries();
7077 
7078 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7079 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
7080 
7081 	register_netdevice_notifier(&ipv6_dev_notf);
7082 
7083 	addrconf_verify();
7084 
7085 	rtnl_af_register(&inet6_ops);
7086 
7087 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETLINK,
7088 				   NULL, inet6_dump_ifinfo, 0);
7089 	if (err < 0)
7090 		goto errout;
7091 
7092 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWADDR,
7093 				   inet6_rtm_newaddr, NULL, 0);
7094 	if (err < 0)
7095 		goto errout;
7096 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELADDR,
7097 				   inet6_rtm_deladdr, NULL, 0);
7098 	if (err < 0)
7099 		goto errout;
7100 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDR,
7101 				   inet6_rtm_getaddr, inet6_dump_ifaddr,
7102 				   RTNL_FLAG_DOIT_UNLOCKED);
7103 	if (err < 0)
7104 		goto errout;
7105 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETMULTICAST,
7106 				   NULL, inet6_dump_ifmcaddr, 0);
7107 	if (err < 0)
7108 		goto errout;
7109 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETANYCAST,
7110 				   NULL, inet6_dump_ifacaddr, 0);
7111 	if (err < 0)
7112 		goto errout;
7113 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETNETCONF,
7114 				   inet6_netconf_get_devconf,
7115 				   inet6_netconf_dump_devconf,
7116 				   RTNL_FLAG_DOIT_UNLOCKED);
7117 	if (err < 0)
7118 		goto errout;
7119 	err = ipv6_addr_label_rtnl_register();
7120 	if (err < 0)
7121 		goto errout;
7122 
7123 	return 0;
7124 errout:
7125 	rtnl_unregister_all(PF_INET6);
7126 	rtnl_af_unregister(&inet6_ops);
7127 	unregister_netdevice_notifier(&ipv6_dev_notf);
7128 errlo:
7129 	destroy_workqueue(addrconf_wq);
7130 out_nowq:
7131 	unregister_pernet_subsys(&addrconf_ops);
7132 out_addrlabel:
7133 	ipv6_addr_label_cleanup();
7134 out:
7135 	return err;
7136 }
7137 
7138 void addrconf_cleanup(void)
7139 {
7140 	struct net_device *dev;
7141 	int i;
7142 
7143 	unregister_netdevice_notifier(&ipv6_dev_notf);
7144 	unregister_pernet_subsys(&addrconf_ops);
7145 	ipv6_addr_label_cleanup();
7146 
7147 	rtnl_af_unregister(&inet6_ops);
7148 
7149 	rtnl_lock();
7150 
7151 	/* clean dev list */
7152 	for_each_netdev(&init_net, dev) {
7153 		if (__in6_dev_get(dev) == NULL)
7154 			continue;
7155 		addrconf_ifdown(dev, 1);
7156 	}
7157 	addrconf_ifdown(init_net.loopback_dev, 2);
7158 
7159 	/*
7160 	 *	Check hash table.
7161 	 */
7162 	spin_lock_bh(&addrconf_hash_lock);
7163 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7164 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
7165 	spin_unlock_bh(&addrconf_hash_lock);
7166 	cancel_delayed_work(&addr_chk_work);
7167 	rtnl_unlock();
7168 
7169 	destroy_workqueue(addrconf_wq);
7170 }
7171