xref: /openbmc/linux/net/ipv6/addrconf.c (revision dd2934a95701576203b2f61e8ded4e4a2f9183ea)
1 /*
2  *	IPv6 Address [auto]configuration
3  *	Linux INET6 implementation
4  *
5  *	Authors:
6  *	Pedro Roque		<roque@di.fc.ul.pt>
7  *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
8  *
9  *	This program is free software; you can redistribute it and/or
10  *      modify it under the terms of the GNU General Public License
11  *      as published by the Free Software Foundation; either version
12  *      2 of the License, or (at your option) any later version.
13  */
14 
15 /*
16  *	Changes:
17  *
18  *	Janos Farkas			:	delete timer on ifdown
19  *	<chexum@bankinf.banki.hu>
20  *	Andi Kleen			:	kill double kfree on module
21  *						unload.
22  *	Maciej W. Rozycki		:	FDDI support
23  *	sekiya@USAGI			:	Don't send too many RS
24  *						packets.
25  *	yoshfuji@USAGI			:       Fixed interval between DAD
26  *						packets.
27  *	YOSHIFUJI Hideaki @USAGI	:	improved accuracy of
28  *						address validation timer.
29  *	YOSHIFUJI Hideaki @USAGI	:	Privacy Extensions (RFC3041)
30  *						support.
31  *	Yuji SEKIYA @USAGI		:	Don't assign a same IPv6
32  *						address on a same interface.
33  *	YOSHIFUJI Hideaki @USAGI	:	ARCnet support
34  *	YOSHIFUJI Hideaki @USAGI	:	convert /proc/net/if_inet6 to
35  *						seq_file.
36  *	YOSHIFUJI Hideaki @USAGI	:	improved source address
37  *						selection; consider scope,
38  *						status etc.
39  */
40 
41 #define pr_fmt(fmt) "IPv6: " fmt
42 
43 #include <linux/errno.h>
44 #include <linux/types.h>
45 #include <linux/kernel.h>
46 #include <linux/sched/signal.h>
47 #include <linux/socket.h>
48 #include <linux/sockios.h>
49 #include <linux/net.h>
50 #include <linux/inet.h>
51 #include <linux/in6.h>
52 #include <linux/netdevice.h>
53 #include <linux/if_addr.h>
54 #include <linux/if_arp.h>
55 #include <linux/if_arcnet.h>
56 #include <linux/if_infiniband.h>
57 #include <linux/route.h>
58 #include <linux/inetdevice.h>
59 #include <linux/init.h>
60 #include <linux/slab.h>
61 #ifdef CONFIG_SYSCTL
62 #include <linux/sysctl.h>
63 #endif
64 #include <linux/capability.h>
65 #include <linux/delay.h>
66 #include <linux/notifier.h>
67 #include <linux/string.h>
68 #include <linux/hash.h>
69 
70 #include <net/net_namespace.h>
71 #include <net/sock.h>
72 #include <net/snmp.h>
73 
74 #include <net/6lowpan.h>
75 #include <net/firewire.h>
76 #include <net/ipv6.h>
77 #include <net/protocol.h>
78 #include <net/ndisc.h>
79 #include <net/ip6_route.h>
80 #include <net/addrconf.h>
81 #include <net/tcp.h>
82 #include <net/ip.h>
83 #include <net/netlink.h>
84 #include <net/pkt_sched.h>
85 #include <net/l3mdev.h>
86 #include <linux/if_tunnel.h>
87 #include <linux/rtnetlink.h>
88 #include <linux/netconf.h>
89 #include <linux/random.h>
90 #include <linux/uaccess.h>
91 #include <asm/unaligned.h>
92 
93 #include <linux/proc_fs.h>
94 #include <linux/seq_file.h>
95 #include <linux/export.h>
96 
97 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
98 
99 #define IPV6_MAX_STRLEN \
100 	sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")
101 
102 static inline u32 cstamp_delta(unsigned long cstamp)
103 {
104 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
105 }
106 
107 static inline s32 rfc3315_s14_backoff_init(s32 irt)
108 {
109 	/* multiply 'initial retransmission time' by 0.9 .. 1.1 */
110 	u64 tmp = (900000 + prandom_u32() % 200001) * (u64)irt;
111 	do_div(tmp, 1000000);
112 	return (s32)tmp;
113 }
114 
115 static inline s32 rfc3315_s14_backoff_update(s32 rt, s32 mrt)
116 {
117 	/* multiply 'retransmission timeout' by 1.9 .. 2.1 */
118 	u64 tmp = (1900000 + prandom_u32() % 200001) * (u64)rt;
119 	do_div(tmp, 1000000);
120 	if ((s32)tmp > mrt) {
121 		/* multiply 'maximum retransmission time' by 0.9 .. 1.1 */
122 		tmp = (900000 + prandom_u32() % 200001) * (u64)mrt;
123 		do_div(tmp, 1000000);
124 	}
125 	return (s32)tmp;
126 }
127 
128 #ifdef CONFIG_SYSCTL
129 static int addrconf_sysctl_register(struct inet6_dev *idev);
130 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
131 #else
132 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
133 {
134 	return 0;
135 }
136 
137 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
138 {
139 }
140 #endif
141 
142 static void ipv6_regen_rndid(struct inet6_dev *idev);
143 static void ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
144 
145 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
146 static int ipv6_count_addresses(const struct inet6_dev *idev);
147 static int ipv6_generate_stable_address(struct in6_addr *addr,
148 					u8 dad_count,
149 					const struct inet6_dev *idev);
150 
151 #define IN6_ADDR_HSIZE_SHIFT	8
152 #define IN6_ADDR_HSIZE		(1 << IN6_ADDR_HSIZE_SHIFT)
153 /*
154  *	Configured unicast address hash table
155  */
156 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
157 static DEFINE_SPINLOCK(addrconf_hash_lock);
158 
159 static void addrconf_verify(void);
160 static void addrconf_verify_rtnl(void);
161 static void addrconf_verify_work(struct work_struct *);
162 
163 static struct workqueue_struct *addrconf_wq;
164 static DECLARE_DELAYED_WORK(addr_chk_work, addrconf_verify_work);
165 
166 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
167 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
168 
169 static void addrconf_type_change(struct net_device *dev,
170 				 unsigned long event);
171 static int addrconf_ifdown(struct net_device *dev, int how);
172 
173 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
174 						  int plen,
175 						  const struct net_device *dev,
176 						  u32 flags, u32 noflags);
177 
178 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
179 static void addrconf_dad_work(struct work_struct *w);
180 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
181 				   bool send_na);
182 static void addrconf_dad_run(struct inet6_dev *idev);
183 static void addrconf_rs_timer(struct timer_list *t);
184 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
185 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
186 
187 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
188 				struct prefix_info *pinfo);
189 
190 static struct ipv6_devconf ipv6_devconf __read_mostly = {
191 	.forwarding		= 0,
192 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
193 	.mtu6			= IPV6_MIN_MTU,
194 	.accept_ra		= 1,
195 	.accept_redirects	= 1,
196 	.autoconf		= 1,
197 	.force_mld_version	= 0,
198 	.mldv1_unsolicited_report_interval = 10 * HZ,
199 	.mldv2_unsolicited_report_interval = HZ,
200 	.dad_transmits		= 1,
201 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
202 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
203 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
204 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
205 	.use_tempaddr		= 0,
206 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
207 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
208 	.regen_max_retry	= REGEN_MAX_RETRY,
209 	.max_desync_factor	= MAX_DESYNC_FACTOR,
210 	.max_addresses		= IPV6_MAX_ADDRESSES,
211 	.accept_ra_defrtr	= 1,
212 	.accept_ra_from_local	= 0,
213 	.accept_ra_min_hop_limit= 1,
214 	.accept_ra_pinfo	= 1,
215 #ifdef CONFIG_IPV6_ROUTER_PREF
216 	.accept_ra_rtr_pref	= 1,
217 	.rtr_probe_interval	= 60 * HZ,
218 #ifdef CONFIG_IPV6_ROUTE_INFO
219 	.accept_ra_rt_info_min_plen = 0,
220 	.accept_ra_rt_info_max_plen = 0,
221 #endif
222 #endif
223 	.proxy_ndp		= 0,
224 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
225 	.disable_ipv6		= 0,
226 	.accept_dad		= 0,
227 	.suppress_frag_ndisc	= 1,
228 	.accept_ra_mtu		= 1,
229 	.stable_secret		= {
230 		.initialized = false,
231 	},
232 	.use_oif_addrs_only	= 0,
233 	.ignore_routes_with_linkdown = 0,
234 	.keep_addr_on_down	= 0,
235 	.seg6_enabled		= 0,
236 #ifdef CONFIG_IPV6_SEG6_HMAC
237 	.seg6_require_hmac	= 0,
238 #endif
239 	.enhanced_dad           = 1,
240 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
241 	.disable_policy		= 0,
242 };
243 
244 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
245 	.forwarding		= 0,
246 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
247 	.mtu6			= IPV6_MIN_MTU,
248 	.accept_ra		= 1,
249 	.accept_redirects	= 1,
250 	.autoconf		= 1,
251 	.force_mld_version	= 0,
252 	.mldv1_unsolicited_report_interval = 10 * HZ,
253 	.mldv2_unsolicited_report_interval = HZ,
254 	.dad_transmits		= 1,
255 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
256 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
257 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
258 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
259 	.use_tempaddr		= 0,
260 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
261 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
262 	.regen_max_retry	= REGEN_MAX_RETRY,
263 	.max_desync_factor	= MAX_DESYNC_FACTOR,
264 	.max_addresses		= IPV6_MAX_ADDRESSES,
265 	.accept_ra_defrtr	= 1,
266 	.accept_ra_from_local	= 0,
267 	.accept_ra_min_hop_limit= 1,
268 	.accept_ra_pinfo	= 1,
269 #ifdef CONFIG_IPV6_ROUTER_PREF
270 	.accept_ra_rtr_pref	= 1,
271 	.rtr_probe_interval	= 60 * HZ,
272 #ifdef CONFIG_IPV6_ROUTE_INFO
273 	.accept_ra_rt_info_min_plen = 0,
274 	.accept_ra_rt_info_max_plen = 0,
275 #endif
276 #endif
277 	.proxy_ndp		= 0,
278 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
279 	.disable_ipv6		= 0,
280 	.accept_dad		= 1,
281 	.suppress_frag_ndisc	= 1,
282 	.accept_ra_mtu		= 1,
283 	.stable_secret		= {
284 		.initialized = false,
285 	},
286 	.use_oif_addrs_only	= 0,
287 	.ignore_routes_with_linkdown = 0,
288 	.keep_addr_on_down	= 0,
289 	.seg6_enabled		= 0,
290 #ifdef CONFIG_IPV6_SEG6_HMAC
291 	.seg6_require_hmac	= 0,
292 #endif
293 	.enhanced_dad           = 1,
294 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
295 	.disable_policy		= 0,
296 };
297 
298 /* Check if link is ready: is it up and is a valid qdisc available */
299 static inline bool addrconf_link_ready(const struct net_device *dev)
300 {
301 	return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
302 }
303 
304 static void addrconf_del_rs_timer(struct inet6_dev *idev)
305 {
306 	if (del_timer(&idev->rs_timer))
307 		__in6_dev_put(idev);
308 }
309 
310 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
311 {
312 	if (cancel_delayed_work(&ifp->dad_work))
313 		__in6_ifa_put(ifp);
314 }
315 
316 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
317 				  unsigned long when)
318 {
319 	if (!timer_pending(&idev->rs_timer))
320 		in6_dev_hold(idev);
321 	mod_timer(&idev->rs_timer, jiffies + when);
322 }
323 
324 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
325 				   unsigned long delay)
326 {
327 	in6_ifa_hold(ifp);
328 	if (mod_delayed_work(addrconf_wq, &ifp->dad_work, delay))
329 		in6_ifa_put(ifp);
330 }
331 
332 static int snmp6_alloc_dev(struct inet6_dev *idev)
333 {
334 	int i;
335 
336 	idev->stats.ipv6 = alloc_percpu(struct ipstats_mib);
337 	if (!idev->stats.ipv6)
338 		goto err_ip;
339 
340 	for_each_possible_cpu(i) {
341 		struct ipstats_mib *addrconf_stats;
342 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
343 		u64_stats_init(&addrconf_stats->syncp);
344 	}
345 
346 
347 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
348 					GFP_KERNEL);
349 	if (!idev->stats.icmpv6dev)
350 		goto err_icmp;
351 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
352 					   GFP_KERNEL);
353 	if (!idev->stats.icmpv6msgdev)
354 		goto err_icmpmsg;
355 
356 	return 0;
357 
358 err_icmpmsg:
359 	kfree(idev->stats.icmpv6dev);
360 err_icmp:
361 	free_percpu(idev->stats.ipv6);
362 err_ip:
363 	return -ENOMEM;
364 }
365 
366 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
367 {
368 	struct inet6_dev *ndev;
369 	int err = -ENOMEM;
370 
371 	ASSERT_RTNL();
372 
373 	if (dev->mtu < IPV6_MIN_MTU)
374 		return ERR_PTR(-EINVAL);
375 
376 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
377 	if (!ndev)
378 		return ERR_PTR(err);
379 
380 	rwlock_init(&ndev->lock);
381 	ndev->dev = dev;
382 	INIT_LIST_HEAD(&ndev->addr_list);
383 	timer_setup(&ndev->rs_timer, addrconf_rs_timer, 0);
384 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
385 
386 	if (ndev->cnf.stable_secret.initialized)
387 		ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
388 
389 	ndev->cnf.mtu6 = dev->mtu;
390 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
391 	if (!ndev->nd_parms) {
392 		kfree(ndev);
393 		return ERR_PTR(err);
394 	}
395 	if (ndev->cnf.forwarding)
396 		dev_disable_lro(dev);
397 	/* We refer to the device */
398 	dev_hold(dev);
399 
400 	if (snmp6_alloc_dev(ndev) < 0) {
401 		netdev_dbg(dev, "%s: cannot allocate memory for statistics\n",
402 			   __func__);
403 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
404 		dev_put(dev);
405 		kfree(ndev);
406 		return ERR_PTR(err);
407 	}
408 
409 	if (snmp6_register_dev(ndev) < 0) {
410 		netdev_dbg(dev, "%s: cannot create /proc/net/dev_snmp6/%s\n",
411 			   __func__, dev->name);
412 		goto err_release;
413 	}
414 
415 	/* One reference from device. */
416 	refcount_set(&ndev->refcnt, 1);
417 
418 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
419 		ndev->cnf.accept_dad = -1;
420 
421 #if IS_ENABLED(CONFIG_IPV6_SIT)
422 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
423 		pr_info("%s: Disabled Multicast RS\n", dev->name);
424 		ndev->cnf.rtr_solicits = 0;
425 	}
426 #endif
427 
428 	INIT_LIST_HEAD(&ndev->tempaddr_list);
429 	ndev->desync_factor = U32_MAX;
430 	if ((dev->flags&IFF_LOOPBACK) ||
431 	    dev->type == ARPHRD_TUNNEL ||
432 	    dev->type == ARPHRD_TUNNEL6 ||
433 	    dev->type == ARPHRD_SIT ||
434 	    dev->type == ARPHRD_NONE) {
435 		ndev->cnf.use_tempaddr = -1;
436 	} else
437 		ipv6_regen_rndid(ndev);
438 
439 	ndev->token = in6addr_any;
440 
441 	if (netif_running(dev) && addrconf_link_ready(dev))
442 		ndev->if_flags |= IF_READY;
443 
444 	ipv6_mc_init_dev(ndev);
445 	ndev->tstamp = jiffies;
446 	err = addrconf_sysctl_register(ndev);
447 	if (err) {
448 		ipv6_mc_destroy_dev(ndev);
449 		snmp6_unregister_dev(ndev);
450 		goto err_release;
451 	}
452 	/* protected by rtnl_lock */
453 	rcu_assign_pointer(dev->ip6_ptr, ndev);
454 
455 	/* Join interface-local all-node multicast group */
456 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
457 
458 	/* Join all-node multicast group */
459 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
460 
461 	/* Join all-router multicast group if forwarding is set */
462 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
463 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
464 
465 	return ndev;
466 
467 err_release:
468 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
469 	ndev->dead = 1;
470 	in6_dev_finish_destroy(ndev);
471 	return ERR_PTR(err);
472 }
473 
474 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
475 {
476 	struct inet6_dev *idev;
477 
478 	ASSERT_RTNL();
479 
480 	idev = __in6_dev_get(dev);
481 	if (!idev) {
482 		idev = ipv6_add_dev(dev);
483 		if (IS_ERR(idev))
484 			return NULL;
485 	}
486 
487 	if (dev->flags&IFF_UP)
488 		ipv6_mc_up(idev);
489 	return idev;
490 }
491 
492 static int inet6_netconf_msgsize_devconf(int type)
493 {
494 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
495 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
496 	bool all = false;
497 
498 	if (type == NETCONFA_ALL)
499 		all = true;
500 
501 	if (all || type == NETCONFA_FORWARDING)
502 		size += nla_total_size(4);
503 #ifdef CONFIG_IPV6_MROUTE
504 	if (all || type == NETCONFA_MC_FORWARDING)
505 		size += nla_total_size(4);
506 #endif
507 	if (all || type == NETCONFA_PROXY_NEIGH)
508 		size += nla_total_size(4);
509 
510 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
511 		size += nla_total_size(4);
512 
513 	return size;
514 }
515 
516 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
517 				      struct ipv6_devconf *devconf, u32 portid,
518 				      u32 seq, int event, unsigned int flags,
519 				      int type)
520 {
521 	struct nlmsghdr  *nlh;
522 	struct netconfmsg *ncm;
523 	bool all = false;
524 
525 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
526 			flags);
527 	if (!nlh)
528 		return -EMSGSIZE;
529 
530 	if (type == NETCONFA_ALL)
531 		all = true;
532 
533 	ncm = nlmsg_data(nlh);
534 	ncm->ncm_family = AF_INET6;
535 
536 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
537 		goto nla_put_failure;
538 
539 	if (!devconf)
540 		goto out;
541 
542 	if ((all || type == NETCONFA_FORWARDING) &&
543 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
544 		goto nla_put_failure;
545 #ifdef CONFIG_IPV6_MROUTE
546 	if ((all || type == NETCONFA_MC_FORWARDING) &&
547 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
548 			devconf->mc_forwarding) < 0)
549 		goto nla_put_failure;
550 #endif
551 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
552 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
553 		goto nla_put_failure;
554 
555 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
556 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
557 			devconf->ignore_routes_with_linkdown) < 0)
558 		goto nla_put_failure;
559 
560 out:
561 	nlmsg_end(skb, nlh);
562 	return 0;
563 
564 nla_put_failure:
565 	nlmsg_cancel(skb, nlh);
566 	return -EMSGSIZE;
567 }
568 
569 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
570 				  int ifindex, struct ipv6_devconf *devconf)
571 {
572 	struct sk_buff *skb;
573 	int err = -ENOBUFS;
574 
575 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
576 	if (!skb)
577 		goto errout;
578 
579 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
580 					 event, 0, type);
581 	if (err < 0) {
582 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
583 		WARN_ON(err == -EMSGSIZE);
584 		kfree_skb(skb);
585 		goto errout;
586 	}
587 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
588 	return;
589 errout:
590 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
591 }
592 
593 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
594 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
595 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
596 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
597 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
598 };
599 
600 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
601 				     struct nlmsghdr *nlh,
602 				     struct netlink_ext_ack *extack)
603 {
604 	struct net *net = sock_net(in_skb->sk);
605 	struct nlattr *tb[NETCONFA_MAX+1];
606 	struct inet6_dev *in6_dev = NULL;
607 	struct net_device *dev = NULL;
608 	struct netconfmsg *ncm;
609 	struct sk_buff *skb;
610 	struct ipv6_devconf *devconf;
611 	int ifindex;
612 	int err;
613 
614 	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
615 			  devconf_ipv6_policy, extack);
616 	if (err < 0)
617 		return err;
618 
619 	if (!tb[NETCONFA_IFINDEX])
620 		return -EINVAL;
621 
622 	err = -EINVAL;
623 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
624 	switch (ifindex) {
625 	case NETCONFA_IFINDEX_ALL:
626 		devconf = net->ipv6.devconf_all;
627 		break;
628 	case NETCONFA_IFINDEX_DEFAULT:
629 		devconf = net->ipv6.devconf_dflt;
630 		break;
631 	default:
632 		dev = dev_get_by_index(net, ifindex);
633 		if (!dev)
634 			return -EINVAL;
635 		in6_dev = in6_dev_get(dev);
636 		if (!in6_dev)
637 			goto errout;
638 		devconf = &in6_dev->cnf;
639 		break;
640 	}
641 
642 	err = -ENOBUFS;
643 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
644 	if (!skb)
645 		goto errout;
646 
647 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
648 					 NETLINK_CB(in_skb).portid,
649 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
650 					 NETCONFA_ALL);
651 	if (err < 0) {
652 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
653 		WARN_ON(err == -EMSGSIZE);
654 		kfree_skb(skb);
655 		goto errout;
656 	}
657 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
658 errout:
659 	if (in6_dev)
660 		in6_dev_put(in6_dev);
661 	if (dev)
662 		dev_put(dev);
663 	return err;
664 }
665 
666 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
667 				      struct netlink_callback *cb)
668 {
669 	struct net *net = sock_net(skb->sk);
670 	int h, s_h;
671 	int idx, s_idx;
672 	struct net_device *dev;
673 	struct inet6_dev *idev;
674 	struct hlist_head *head;
675 
676 	s_h = cb->args[0];
677 	s_idx = idx = cb->args[1];
678 
679 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
680 		idx = 0;
681 		head = &net->dev_index_head[h];
682 		rcu_read_lock();
683 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
684 			  net->dev_base_seq;
685 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
686 			if (idx < s_idx)
687 				goto cont;
688 			idev = __in6_dev_get(dev);
689 			if (!idev)
690 				goto cont;
691 
692 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
693 						       &idev->cnf,
694 						       NETLINK_CB(cb->skb).portid,
695 						       cb->nlh->nlmsg_seq,
696 						       RTM_NEWNETCONF,
697 						       NLM_F_MULTI,
698 						       NETCONFA_ALL) < 0) {
699 				rcu_read_unlock();
700 				goto done;
701 			}
702 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
703 cont:
704 			idx++;
705 		}
706 		rcu_read_unlock();
707 	}
708 	if (h == NETDEV_HASHENTRIES) {
709 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
710 					       net->ipv6.devconf_all,
711 					       NETLINK_CB(cb->skb).portid,
712 					       cb->nlh->nlmsg_seq,
713 					       RTM_NEWNETCONF, NLM_F_MULTI,
714 					       NETCONFA_ALL) < 0)
715 			goto done;
716 		else
717 			h++;
718 	}
719 	if (h == NETDEV_HASHENTRIES + 1) {
720 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
721 					       net->ipv6.devconf_dflt,
722 					       NETLINK_CB(cb->skb).portid,
723 					       cb->nlh->nlmsg_seq,
724 					       RTM_NEWNETCONF, NLM_F_MULTI,
725 					       NETCONFA_ALL) < 0)
726 			goto done;
727 		else
728 			h++;
729 	}
730 done:
731 	cb->args[0] = h;
732 	cb->args[1] = idx;
733 
734 	return skb->len;
735 }
736 
737 #ifdef CONFIG_SYSCTL
738 static void dev_forward_change(struct inet6_dev *idev)
739 {
740 	struct net_device *dev;
741 	struct inet6_ifaddr *ifa;
742 
743 	if (!idev)
744 		return;
745 	dev = idev->dev;
746 	if (idev->cnf.forwarding)
747 		dev_disable_lro(dev);
748 	if (dev->flags & IFF_MULTICAST) {
749 		if (idev->cnf.forwarding) {
750 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
751 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
752 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
753 		} else {
754 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
755 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
756 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
757 		}
758 	}
759 
760 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
761 		if (ifa->flags&IFA_F_TENTATIVE)
762 			continue;
763 		if (idev->cnf.forwarding)
764 			addrconf_join_anycast(ifa);
765 		else
766 			addrconf_leave_anycast(ifa);
767 	}
768 	inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
769 				     NETCONFA_FORWARDING,
770 				     dev->ifindex, &idev->cnf);
771 }
772 
773 
774 static void addrconf_forward_change(struct net *net, __s32 newf)
775 {
776 	struct net_device *dev;
777 	struct inet6_dev *idev;
778 
779 	for_each_netdev(net, dev) {
780 		idev = __in6_dev_get(dev);
781 		if (idev) {
782 			int changed = (!idev->cnf.forwarding) ^ (!newf);
783 			idev->cnf.forwarding = newf;
784 			if (changed)
785 				dev_forward_change(idev);
786 		}
787 	}
788 }
789 
790 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
791 {
792 	struct net *net;
793 	int old;
794 
795 	if (!rtnl_trylock())
796 		return restart_syscall();
797 
798 	net = (struct net *)table->extra2;
799 	old = *p;
800 	*p = newf;
801 
802 	if (p == &net->ipv6.devconf_dflt->forwarding) {
803 		if ((!newf) ^ (!old))
804 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
805 						     NETCONFA_FORWARDING,
806 						     NETCONFA_IFINDEX_DEFAULT,
807 						     net->ipv6.devconf_dflt);
808 		rtnl_unlock();
809 		return 0;
810 	}
811 
812 	if (p == &net->ipv6.devconf_all->forwarding) {
813 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
814 
815 		net->ipv6.devconf_dflt->forwarding = newf;
816 		if ((!newf) ^ (!old_dflt))
817 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
818 						     NETCONFA_FORWARDING,
819 						     NETCONFA_IFINDEX_DEFAULT,
820 						     net->ipv6.devconf_dflt);
821 
822 		addrconf_forward_change(net, newf);
823 		if ((!newf) ^ (!old))
824 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
825 						     NETCONFA_FORWARDING,
826 						     NETCONFA_IFINDEX_ALL,
827 						     net->ipv6.devconf_all);
828 	} else if ((!newf) ^ (!old))
829 		dev_forward_change((struct inet6_dev *)table->extra1);
830 	rtnl_unlock();
831 
832 	if (newf)
833 		rt6_purge_dflt_routers(net);
834 	return 1;
835 }
836 
837 static void addrconf_linkdown_change(struct net *net, __s32 newf)
838 {
839 	struct net_device *dev;
840 	struct inet6_dev *idev;
841 
842 	for_each_netdev(net, dev) {
843 		idev = __in6_dev_get(dev);
844 		if (idev) {
845 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
846 
847 			idev->cnf.ignore_routes_with_linkdown = newf;
848 			if (changed)
849 				inet6_netconf_notify_devconf(dev_net(dev),
850 							     RTM_NEWNETCONF,
851 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
852 							     dev->ifindex,
853 							     &idev->cnf);
854 		}
855 	}
856 }
857 
858 static int addrconf_fixup_linkdown(struct ctl_table *table, int *p, int newf)
859 {
860 	struct net *net;
861 	int old;
862 
863 	if (!rtnl_trylock())
864 		return restart_syscall();
865 
866 	net = (struct net *)table->extra2;
867 	old = *p;
868 	*p = newf;
869 
870 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
871 		if ((!newf) ^ (!old))
872 			inet6_netconf_notify_devconf(net,
873 						     RTM_NEWNETCONF,
874 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
875 						     NETCONFA_IFINDEX_DEFAULT,
876 						     net->ipv6.devconf_dflt);
877 		rtnl_unlock();
878 		return 0;
879 	}
880 
881 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
882 		net->ipv6.devconf_dflt->ignore_routes_with_linkdown = newf;
883 		addrconf_linkdown_change(net, newf);
884 		if ((!newf) ^ (!old))
885 			inet6_netconf_notify_devconf(net,
886 						     RTM_NEWNETCONF,
887 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
888 						     NETCONFA_IFINDEX_ALL,
889 						     net->ipv6.devconf_all);
890 	}
891 	rtnl_unlock();
892 
893 	return 1;
894 }
895 
896 #endif
897 
898 /* Nobody refers to this ifaddr, destroy it */
899 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
900 {
901 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
902 
903 #ifdef NET_REFCNT_DEBUG
904 	pr_debug("%s\n", __func__);
905 #endif
906 
907 	in6_dev_put(ifp->idev);
908 
909 	if (cancel_delayed_work(&ifp->dad_work))
910 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
911 			  ifp);
912 
913 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
914 		pr_warn("Freeing alive inet6 address %p\n", ifp);
915 		return;
916 	}
917 
918 	kfree_rcu(ifp, rcu);
919 }
920 
921 static void
922 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
923 {
924 	struct list_head *p;
925 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
926 
927 	/*
928 	 * Each device address list is sorted in order of scope -
929 	 * global before linklocal.
930 	 */
931 	list_for_each(p, &idev->addr_list) {
932 		struct inet6_ifaddr *ifa
933 			= list_entry(p, struct inet6_ifaddr, if_list);
934 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
935 			break;
936 	}
937 
938 	list_add_tail_rcu(&ifp->if_list, p);
939 }
940 
941 static u32 inet6_addr_hash(const struct net *net, const struct in6_addr *addr)
942 {
943 	u32 val = ipv6_addr_hash(addr) ^ net_hash_mix(net);
944 
945 	return hash_32(val, IN6_ADDR_HSIZE_SHIFT);
946 }
947 
948 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
949 			       struct net_device *dev, unsigned int hash)
950 {
951 	struct inet6_ifaddr *ifp;
952 
953 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
954 		if (!net_eq(dev_net(ifp->idev->dev), net))
955 			continue;
956 		if (ipv6_addr_equal(&ifp->addr, addr)) {
957 			if (!dev || ifp->idev->dev == dev)
958 				return true;
959 		}
960 	}
961 	return false;
962 }
963 
964 static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
965 {
966 	unsigned int hash = inet6_addr_hash(dev_net(dev), &ifa->addr);
967 	int err = 0;
968 
969 	spin_lock(&addrconf_hash_lock);
970 
971 	/* Ignore adding duplicate addresses on an interface */
972 	if (ipv6_chk_same_addr(dev_net(dev), &ifa->addr, dev, hash)) {
973 		netdev_dbg(dev, "ipv6_add_addr: already assigned\n");
974 		err = -EEXIST;
975 	} else {
976 		hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
977 	}
978 
979 	spin_unlock(&addrconf_hash_lock);
980 
981 	return err;
982 }
983 
984 /* On success it returns ifp with increased reference count */
985 
986 static struct inet6_ifaddr *
987 ipv6_add_addr(struct inet6_dev *idev, struct ifa6_config *cfg,
988 	      bool can_block, struct netlink_ext_ack *extack)
989 {
990 	gfp_t gfp_flags = can_block ? GFP_KERNEL : GFP_ATOMIC;
991 	int addr_type = ipv6_addr_type(cfg->pfx);
992 	struct net *net = dev_net(idev->dev);
993 	struct inet6_ifaddr *ifa = NULL;
994 	struct fib6_info *f6i = NULL;
995 	int err = 0;
996 
997 	if (addr_type == IPV6_ADDR_ANY ||
998 	    addr_type & IPV6_ADDR_MULTICAST ||
999 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
1000 	     addr_type & IPV6_ADDR_LOOPBACK))
1001 		return ERR_PTR(-EADDRNOTAVAIL);
1002 
1003 	if (idev->dead) {
1004 		err = -ENODEV;			/*XXX*/
1005 		goto out;
1006 	}
1007 
1008 	if (idev->cnf.disable_ipv6) {
1009 		err = -EACCES;
1010 		goto out;
1011 	}
1012 
1013 	/* validator notifier needs to be blocking;
1014 	 * do not call in atomic context
1015 	 */
1016 	if (can_block) {
1017 		struct in6_validator_info i6vi = {
1018 			.i6vi_addr = *cfg->pfx,
1019 			.i6vi_dev = idev,
1020 			.extack = extack,
1021 		};
1022 
1023 		err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
1024 		err = notifier_to_errno(err);
1025 		if (err < 0)
1026 			goto out;
1027 	}
1028 
1029 	ifa = kzalloc(sizeof(*ifa), gfp_flags);
1030 	if (!ifa) {
1031 		err = -ENOBUFS;
1032 		goto out;
1033 	}
1034 
1035 	f6i = addrconf_f6i_alloc(net, idev, cfg->pfx, false, gfp_flags);
1036 	if (IS_ERR(f6i)) {
1037 		err = PTR_ERR(f6i);
1038 		f6i = NULL;
1039 		goto out;
1040 	}
1041 
1042 	if (net->ipv6.devconf_all->disable_policy ||
1043 	    idev->cnf.disable_policy)
1044 		f6i->dst_nopolicy = true;
1045 
1046 	neigh_parms_data_state_setall(idev->nd_parms);
1047 
1048 	ifa->addr = *cfg->pfx;
1049 	if (cfg->peer_pfx)
1050 		ifa->peer_addr = *cfg->peer_pfx;
1051 
1052 	spin_lock_init(&ifa->lock);
1053 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1054 	INIT_HLIST_NODE(&ifa->addr_lst);
1055 	ifa->scope = cfg->scope;
1056 	ifa->prefix_len = cfg->plen;
1057 	ifa->rt_priority = cfg->rt_priority;
1058 	ifa->flags = cfg->ifa_flags;
1059 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1060 	if (!(cfg->ifa_flags & IFA_F_NODAD))
1061 		ifa->flags |= IFA_F_TENTATIVE;
1062 	ifa->valid_lft = cfg->valid_lft;
1063 	ifa->prefered_lft = cfg->preferred_lft;
1064 	ifa->cstamp = ifa->tstamp = jiffies;
1065 	ifa->tokenized = false;
1066 
1067 	ifa->rt = f6i;
1068 
1069 	ifa->idev = idev;
1070 	in6_dev_hold(idev);
1071 
1072 	/* For caller */
1073 	refcount_set(&ifa->refcnt, 1);
1074 
1075 	rcu_read_lock_bh();
1076 
1077 	err = ipv6_add_addr_hash(idev->dev, ifa);
1078 	if (err < 0) {
1079 		rcu_read_unlock_bh();
1080 		goto out;
1081 	}
1082 
1083 	write_lock(&idev->lock);
1084 
1085 	/* Add to inet6_dev unicast addr list. */
1086 	ipv6_link_dev_addr(idev, ifa);
1087 
1088 	if (ifa->flags&IFA_F_TEMPORARY) {
1089 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1090 		in6_ifa_hold(ifa);
1091 	}
1092 
1093 	in6_ifa_hold(ifa);
1094 	write_unlock(&idev->lock);
1095 
1096 	rcu_read_unlock_bh();
1097 
1098 	inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1099 out:
1100 	if (unlikely(err < 0)) {
1101 		fib6_info_release(f6i);
1102 
1103 		if (ifa) {
1104 			if (ifa->idev)
1105 				in6_dev_put(ifa->idev);
1106 			kfree(ifa);
1107 		}
1108 		ifa = ERR_PTR(err);
1109 	}
1110 
1111 	return ifa;
1112 }
1113 
1114 enum cleanup_prefix_rt_t {
1115 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1116 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1117 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1118 };
1119 
1120 /*
1121  * Check, whether the prefix for ifp would still need a prefix route
1122  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1123  * constants.
1124  *
1125  * 1) we don't purge prefix if address was not permanent.
1126  *    prefix is managed by its own lifetime.
1127  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1128  * 3) if there are no addresses, delete prefix.
1129  * 4) if there are still other permanent address(es),
1130  *    corresponding prefix is still permanent.
1131  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1132  *    don't purge the prefix, assume user space is managing it.
1133  * 6) otherwise, update prefix lifetime to the
1134  *    longest valid lifetime among the corresponding
1135  *    addresses on the device.
1136  *    Note: subsequent RA will update lifetime.
1137  **/
1138 static enum cleanup_prefix_rt_t
1139 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1140 {
1141 	struct inet6_ifaddr *ifa;
1142 	struct inet6_dev *idev = ifp->idev;
1143 	unsigned long lifetime;
1144 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1145 
1146 	*expires = jiffies;
1147 
1148 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1149 		if (ifa == ifp)
1150 			continue;
1151 		if (!ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1152 				       ifp->prefix_len))
1153 			continue;
1154 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1155 			return CLEANUP_PREFIX_RT_NOP;
1156 
1157 		action = CLEANUP_PREFIX_RT_EXPIRE;
1158 
1159 		spin_lock(&ifa->lock);
1160 
1161 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1162 		/*
1163 		 * Note: Because this address is
1164 		 * not permanent, lifetime <
1165 		 * LONG_MAX / HZ here.
1166 		 */
1167 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1168 			*expires = ifa->tstamp + lifetime * HZ;
1169 		spin_unlock(&ifa->lock);
1170 	}
1171 
1172 	return action;
1173 }
1174 
1175 static void
1176 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires, bool del_rt)
1177 {
1178 	struct fib6_info *f6i;
1179 
1180 	f6i = addrconf_get_prefix_route(&ifp->addr,
1181 				       ifp->prefix_len,
1182 				       ifp->idev->dev,
1183 				       0, RTF_GATEWAY | RTF_DEFAULT);
1184 	if (f6i) {
1185 		if (del_rt)
1186 			ip6_del_rt(dev_net(ifp->idev->dev), f6i);
1187 		else {
1188 			if (!(f6i->fib6_flags & RTF_EXPIRES))
1189 				fib6_set_expires(f6i, expires);
1190 			fib6_info_release(f6i);
1191 		}
1192 	}
1193 }
1194 
1195 
1196 /* This function wants to get referenced ifp and releases it before return */
1197 
1198 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1199 {
1200 	int state;
1201 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1202 	unsigned long expires;
1203 
1204 	ASSERT_RTNL();
1205 
1206 	spin_lock_bh(&ifp->lock);
1207 	state = ifp->state;
1208 	ifp->state = INET6_IFADDR_STATE_DEAD;
1209 	spin_unlock_bh(&ifp->lock);
1210 
1211 	if (state == INET6_IFADDR_STATE_DEAD)
1212 		goto out;
1213 
1214 	spin_lock_bh(&addrconf_hash_lock);
1215 	hlist_del_init_rcu(&ifp->addr_lst);
1216 	spin_unlock_bh(&addrconf_hash_lock);
1217 
1218 	write_lock_bh(&ifp->idev->lock);
1219 
1220 	if (ifp->flags&IFA_F_TEMPORARY) {
1221 		list_del(&ifp->tmp_list);
1222 		if (ifp->ifpub) {
1223 			in6_ifa_put(ifp->ifpub);
1224 			ifp->ifpub = NULL;
1225 		}
1226 		__in6_ifa_put(ifp);
1227 	}
1228 
1229 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1230 		action = check_cleanup_prefix_route(ifp, &expires);
1231 
1232 	list_del_rcu(&ifp->if_list);
1233 	__in6_ifa_put(ifp);
1234 
1235 	write_unlock_bh(&ifp->idev->lock);
1236 
1237 	addrconf_del_dad_work(ifp);
1238 
1239 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1240 
1241 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1242 
1243 	if (action != CLEANUP_PREFIX_RT_NOP) {
1244 		cleanup_prefix_route(ifp, expires,
1245 			action == CLEANUP_PREFIX_RT_DEL);
1246 	}
1247 
1248 	/* clean up prefsrc entries */
1249 	rt6_remove_prefsrc(ifp);
1250 out:
1251 	in6_ifa_put(ifp);
1252 }
1253 
1254 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp,
1255 				struct inet6_ifaddr *ift,
1256 				bool block)
1257 {
1258 	struct inet6_dev *idev = ifp->idev;
1259 	struct in6_addr addr, *tmpaddr;
1260 	unsigned long tmp_tstamp, age;
1261 	unsigned long regen_advance;
1262 	struct ifa6_config cfg;
1263 	int ret = 0;
1264 	unsigned long now = jiffies;
1265 	long max_desync_factor;
1266 	s32 cnf_temp_preferred_lft;
1267 
1268 	write_lock_bh(&idev->lock);
1269 	if (ift) {
1270 		spin_lock_bh(&ift->lock);
1271 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
1272 		spin_unlock_bh(&ift->lock);
1273 		tmpaddr = &addr;
1274 	} else {
1275 		tmpaddr = NULL;
1276 	}
1277 retry:
1278 	in6_dev_hold(idev);
1279 	if (idev->cnf.use_tempaddr <= 0) {
1280 		write_unlock_bh(&idev->lock);
1281 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1282 		in6_dev_put(idev);
1283 		ret = -1;
1284 		goto out;
1285 	}
1286 	spin_lock_bh(&ifp->lock);
1287 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1288 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1289 		spin_unlock_bh(&ifp->lock);
1290 		write_unlock_bh(&idev->lock);
1291 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1292 			__func__);
1293 		in6_dev_put(idev);
1294 		ret = -1;
1295 		goto out;
1296 	}
1297 	in6_ifa_hold(ifp);
1298 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1299 	ipv6_try_regen_rndid(idev, tmpaddr);
1300 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1301 	age = (now - ifp->tstamp) / HZ;
1302 
1303 	regen_advance = idev->cnf.regen_max_retry *
1304 			idev->cnf.dad_transmits *
1305 			NEIGH_VAR(idev->nd_parms, RETRANS_TIME) / HZ;
1306 
1307 	/* recalculate max_desync_factor each time and update
1308 	 * idev->desync_factor if it's larger
1309 	 */
1310 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1311 	max_desync_factor = min_t(__u32,
1312 				  idev->cnf.max_desync_factor,
1313 				  cnf_temp_preferred_lft - regen_advance);
1314 
1315 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1316 		if (max_desync_factor > 0) {
1317 			get_random_bytes(&idev->desync_factor,
1318 					 sizeof(idev->desync_factor));
1319 			idev->desync_factor %= max_desync_factor;
1320 		} else {
1321 			idev->desync_factor = 0;
1322 		}
1323 	}
1324 
1325 	memset(&cfg, 0, sizeof(cfg));
1326 	cfg.valid_lft = min_t(__u32, ifp->valid_lft,
1327 			      idev->cnf.temp_valid_lft + age);
1328 	cfg.preferred_lft = cnf_temp_preferred_lft + age - idev->desync_factor;
1329 	cfg.preferred_lft = min_t(__u32, ifp->prefered_lft, cfg.preferred_lft);
1330 
1331 	cfg.plen = ifp->prefix_len;
1332 	tmp_tstamp = ifp->tstamp;
1333 	spin_unlock_bh(&ifp->lock);
1334 
1335 	write_unlock_bh(&idev->lock);
1336 
1337 	/* A temporary address is created only if this calculated Preferred
1338 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1339 	 * an implementation must not create a temporary address with a zero
1340 	 * Preferred Lifetime.
1341 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1342 	 * temporary addresses being generated.
1343 	 */
1344 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1345 	if (cfg.preferred_lft <= regen_advance + age) {
1346 		in6_ifa_put(ifp);
1347 		in6_dev_put(idev);
1348 		ret = -1;
1349 		goto out;
1350 	}
1351 
1352 	cfg.ifa_flags = IFA_F_TEMPORARY;
1353 	/* set in addrconf_prefix_rcv() */
1354 	if (ifp->flags & IFA_F_OPTIMISTIC)
1355 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
1356 
1357 	cfg.pfx = &addr;
1358 	cfg.scope = ipv6_addr_scope(cfg.pfx);
1359 
1360 	ift = ipv6_add_addr(idev, &cfg, block, NULL);
1361 	if (IS_ERR(ift)) {
1362 		in6_ifa_put(ifp);
1363 		in6_dev_put(idev);
1364 		pr_info("%s: retry temporary address regeneration\n", __func__);
1365 		tmpaddr = &addr;
1366 		write_lock_bh(&idev->lock);
1367 		goto retry;
1368 	}
1369 
1370 	spin_lock_bh(&ift->lock);
1371 	ift->ifpub = ifp;
1372 	ift->cstamp = now;
1373 	ift->tstamp = tmp_tstamp;
1374 	spin_unlock_bh(&ift->lock);
1375 
1376 	addrconf_dad_start(ift);
1377 	in6_ifa_put(ift);
1378 	in6_dev_put(idev);
1379 out:
1380 	return ret;
1381 }
1382 
1383 /*
1384  *	Choose an appropriate source address (RFC3484)
1385  */
1386 enum {
1387 	IPV6_SADDR_RULE_INIT = 0,
1388 	IPV6_SADDR_RULE_LOCAL,
1389 	IPV6_SADDR_RULE_SCOPE,
1390 	IPV6_SADDR_RULE_PREFERRED,
1391 #ifdef CONFIG_IPV6_MIP6
1392 	IPV6_SADDR_RULE_HOA,
1393 #endif
1394 	IPV6_SADDR_RULE_OIF,
1395 	IPV6_SADDR_RULE_LABEL,
1396 	IPV6_SADDR_RULE_PRIVACY,
1397 	IPV6_SADDR_RULE_ORCHID,
1398 	IPV6_SADDR_RULE_PREFIX,
1399 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1400 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1401 #endif
1402 	IPV6_SADDR_RULE_MAX
1403 };
1404 
1405 struct ipv6_saddr_score {
1406 	int			rule;
1407 	int			addr_type;
1408 	struct inet6_ifaddr	*ifa;
1409 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1410 	int			scopedist;
1411 	int			matchlen;
1412 };
1413 
1414 struct ipv6_saddr_dst {
1415 	const struct in6_addr *addr;
1416 	int ifindex;
1417 	int scope;
1418 	int label;
1419 	unsigned int prefs;
1420 };
1421 
1422 static inline int ipv6_saddr_preferred(int type)
1423 {
1424 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1425 		return 1;
1426 	return 0;
1427 }
1428 
1429 static bool ipv6_use_optimistic_addr(struct net *net,
1430 				     struct inet6_dev *idev)
1431 {
1432 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1433 	if (!idev)
1434 		return false;
1435 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1436 		return false;
1437 	if (!net->ipv6.devconf_all->use_optimistic && !idev->cnf.use_optimistic)
1438 		return false;
1439 
1440 	return true;
1441 #else
1442 	return false;
1443 #endif
1444 }
1445 
1446 static bool ipv6_allow_optimistic_dad(struct net *net,
1447 				      struct inet6_dev *idev)
1448 {
1449 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1450 	if (!idev)
1451 		return false;
1452 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1453 		return false;
1454 
1455 	return true;
1456 #else
1457 	return false;
1458 #endif
1459 }
1460 
1461 static int ipv6_get_saddr_eval(struct net *net,
1462 			       struct ipv6_saddr_score *score,
1463 			       struct ipv6_saddr_dst *dst,
1464 			       int i)
1465 {
1466 	int ret;
1467 
1468 	if (i <= score->rule) {
1469 		switch (i) {
1470 		case IPV6_SADDR_RULE_SCOPE:
1471 			ret = score->scopedist;
1472 			break;
1473 		case IPV6_SADDR_RULE_PREFIX:
1474 			ret = score->matchlen;
1475 			break;
1476 		default:
1477 			ret = !!test_bit(i, score->scorebits);
1478 		}
1479 		goto out;
1480 	}
1481 
1482 	switch (i) {
1483 	case IPV6_SADDR_RULE_INIT:
1484 		/* Rule 0: remember if hiscore is not ready yet */
1485 		ret = !!score->ifa;
1486 		break;
1487 	case IPV6_SADDR_RULE_LOCAL:
1488 		/* Rule 1: Prefer same address */
1489 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1490 		break;
1491 	case IPV6_SADDR_RULE_SCOPE:
1492 		/* Rule 2: Prefer appropriate scope
1493 		 *
1494 		 *      ret
1495 		 *       ^
1496 		 *    -1 |  d 15
1497 		 *    ---+--+-+---> scope
1498 		 *       |
1499 		 *       |             d is scope of the destination.
1500 		 *  B-d  |  \
1501 		 *       |   \      <- smaller scope is better if
1502 		 *  B-15 |    \        if scope is enough for destination.
1503 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1504 		 * d-C-1 | /
1505 		 *       |/         <- greater is better
1506 		 *   -C  /             if scope is not enough for destination.
1507 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1508 		 *
1509 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1510 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1511 		 * Assume B = 0 and we get C > 29.
1512 		 */
1513 		ret = __ipv6_addr_src_scope(score->addr_type);
1514 		if (ret >= dst->scope)
1515 			ret = -ret;
1516 		else
1517 			ret -= 128;	/* 30 is enough */
1518 		score->scopedist = ret;
1519 		break;
1520 	case IPV6_SADDR_RULE_PREFERRED:
1521 	    {
1522 		/* Rule 3: Avoid deprecated and optimistic addresses */
1523 		u8 avoid = IFA_F_DEPRECATED;
1524 
1525 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1526 			avoid |= IFA_F_OPTIMISTIC;
1527 		ret = ipv6_saddr_preferred(score->addr_type) ||
1528 		      !(score->ifa->flags & avoid);
1529 		break;
1530 	    }
1531 #ifdef CONFIG_IPV6_MIP6
1532 	case IPV6_SADDR_RULE_HOA:
1533 	    {
1534 		/* Rule 4: Prefer home address */
1535 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1536 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1537 		break;
1538 	    }
1539 #endif
1540 	case IPV6_SADDR_RULE_OIF:
1541 		/* Rule 5: Prefer outgoing interface */
1542 		ret = (!dst->ifindex ||
1543 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1544 		break;
1545 	case IPV6_SADDR_RULE_LABEL:
1546 		/* Rule 6: Prefer matching label */
1547 		ret = ipv6_addr_label(net,
1548 				      &score->ifa->addr, score->addr_type,
1549 				      score->ifa->idev->dev->ifindex) == dst->label;
1550 		break;
1551 	case IPV6_SADDR_RULE_PRIVACY:
1552 	    {
1553 		/* Rule 7: Prefer public address
1554 		 * Note: prefer temporary address if use_tempaddr >= 2
1555 		 */
1556 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1557 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1558 				score->ifa->idev->cnf.use_tempaddr >= 2;
1559 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1560 		break;
1561 	    }
1562 	case IPV6_SADDR_RULE_ORCHID:
1563 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1564 		 *	    non-ORCHID vs non-ORCHID
1565 		 */
1566 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1567 			ipv6_addr_orchid(dst->addr));
1568 		break;
1569 	case IPV6_SADDR_RULE_PREFIX:
1570 		/* Rule 8: Use longest matching prefix */
1571 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1572 		if (ret > score->ifa->prefix_len)
1573 			ret = score->ifa->prefix_len;
1574 		score->matchlen = ret;
1575 		break;
1576 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1577 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1578 		/* Optimistic addresses still have lower precedence than other
1579 		 * preferred addresses.
1580 		 */
1581 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1582 		break;
1583 #endif
1584 	default:
1585 		ret = 0;
1586 	}
1587 
1588 	if (ret)
1589 		__set_bit(i, score->scorebits);
1590 	score->rule = i;
1591 out:
1592 	return ret;
1593 }
1594 
1595 static int __ipv6_dev_get_saddr(struct net *net,
1596 				struct ipv6_saddr_dst *dst,
1597 				struct inet6_dev *idev,
1598 				struct ipv6_saddr_score *scores,
1599 				int hiscore_idx)
1600 {
1601 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1602 
1603 	list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1604 		int i;
1605 
1606 		/*
1607 		 * - Tentative Address (RFC2462 section 5.4)
1608 		 *  - A tentative address is not considered
1609 		 *    "assigned to an interface" in the traditional
1610 		 *    sense, unless it is also flagged as optimistic.
1611 		 * - Candidate Source Address (section 4)
1612 		 *  - In any case, anycast addresses, multicast
1613 		 *    addresses, and the unspecified address MUST
1614 		 *    NOT be included in a candidate set.
1615 		 */
1616 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1617 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1618 			continue;
1619 
1620 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1621 
1622 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1623 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1624 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1625 					    idev->dev->name);
1626 			continue;
1627 		}
1628 
1629 		score->rule = -1;
1630 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1631 
1632 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1633 			int minihiscore, miniscore;
1634 
1635 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1636 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1637 
1638 			if (minihiscore > miniscore) {
1639 				if (i == IPV6_SADDR_RULE_SCOPE &&
1640 				    score->scopedist > 0) {
1641 					/*
1642 					 * special case:
1643 					 * each remaining entry
1644 					 * has too small (not enough)
1645 					 * scope, because ifa entries
1646 					 * are sorted by their scope
1647 					 * values.
1648 					 */
1649 					goto out;
1650 				}
1651 				break;
1652 			} else if (minihiscore < miniscore) {
1653 				swap(hiscore, score);
1654 				hiscore_idx = 1 - hiscore_idx;
1655 
1656 				/* restore our iterator */
1657 				score->ifa = hiscore->ifa;
1658 
1659 				break;
1660 			}
1661 		}
1662 	}
1663 out:
1664 	return hiscore_idx;
1665 }
1666 
1667 static int ipv6_get_saddr_master(struct net *net,
1668 				 const struct net_device *dst_dev,
1669 				 const struct net_device *master,
1670 				 struct ipv6_saddr_dst *dst,
1671 				 struct ipv6_saddr_score *scores,
1672 				 int hiscore_idx)
1673 {
1674 	struct inet6_dev *idev;
1675 
1676 	idev = __in6_dev_get(dst_dev);
1677 	if (idev)
1678 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1679 						   scores, hiscore_idx);
1680 
1681 	idev = __in6_dev_get(master);
1682 	if (idev)
1683 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1684 						   scores, hiscore_idx);
1685 
1686 	return hiscore_idx;
1687 }
1688 
1689 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1690 		       const struct in6_addr *daddr, unsigned int prefs,
1691 		       struct in6_addr *saddr)
1692 {
1693 	struct ipv6_saddr_score scores[2], *hiscore;
1694 	struct ipv6_saddr_dst dst;
1695 	struct inet6_dev *idev;
1696 	struct net_device *dev;
1697 	int dst_type;
1698 	bool use_oif_addr = false;
1699 	int hiscore_idx = 0;
1700 	int ret = 0;
1701 
1702 	dst_type = __ipv6_addr_type(daddr);
1703 	dst.addr = daddr;
1704 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1705 	dst.scope = __ipv6_addr_src_scope(dst_type);
1706 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1707 	dst.prefs = prefs;
1708 
1709 	scores[hiscore_idx].rule = -1;
1710 	scores[hiscore_idx].ifa = NULL;
1711 
1712 	rcu_read_lock();
1713 
1714 	/* Candidate Source Address (section 4)
1715 	 *  - multicast and link-local destination address,
1716 	 *    the set of candidate source address MUST only
1717 	 *    include addresses assigned to interfaces
1718 	 *    belonging to the same link as the outgoing
1719 	 *    interface.
1720 	 * (- For site-local destination addresses, the
1721 	 *    set of candidate source addresses MUST only
1722 	 *    include addresses assigned to interfaces
1723 	 *    belonging to the same site as the outgoing
1724 	 *    interface.)
1725 	 *  - "It is RECOMMENDED that the candidate source addresses
1726 	 *    be the set of unicast addresses assigned to the
1727 	 *    interface that will be used to send to the destination
1728 	 *    (the 'outgoing' interface)." (RFC 6724)
1729 	 */
1730 	if (dst_dev) {
1731 		idev = __in6_dev_get(dst_dev);
1732 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1733 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1734 		    (idev && idev->cnf.use_oif_addrs_only)) {
1735 			use_oif_addr = true;
1736 		}
1737 	}
1738 
1739 	if (use_oif_addr) {
1740 		if (idev)
1741 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1742 	} else {
1743 		const struct net_device *master;
1744 		int master_idx = 0;
1745 
1746 		/* if dst_dev exists and is enslaved to an L3 device, then
1747 		 * prefer addresses from dst_dev and then the master over
1748 		 * any other enslaved devices in the L3 domain.
1749 		 */
1750 		master = l3mdev_master_dev_rcu(dst_dev);
1751 		if (master) {
1752 			master_idx = master->ifindex;
1753 
1754 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1755 							    master, &dst,
1756 							    scores, hiscore_idx);
1757 
1758 			if (scores[hiscore_idx].ifa)
1759 				goto out;
1760 		}
1761 
1762 		for_each_netdev_rcu(net, dev) {
1763 			/* only consider addresses on devices in the
1764 			 * same L3 domain
1765 			 */
1766 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1767 				continue;
1768 			idev = __in6_dev_get(dev);
1769 			if (!idev)
1770 				continue;
1771 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1772 		}
1773 	}
1774 
1775 out:
1776 	hiscore = &scores[hiscore_idx];
1777 	if (!hiscore->ifa)
1778 		ret = -EADDRNOTAVAIL;
1779 	else
1780 		*saddr = hiscore->ifa->addr;
1781 
1782 	rcu_read_unlock();
1783 	return ret;
1784 }
1785 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1786 
1787 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1788 		      u32 banned_flags)
1789 {
1790 	struct inet6_ifaddr *ifp;
1791 	int err = -EADDRNOTAVAIL;
1792 
1793 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1794 		if (ifp->scope > IFA_LINK)
1795 			break;
1796 		if (ifp->scope == IFA_LINK &&
1797 		    !(ifp->flags & banned_flags)) {
1798 			*addr = ifp->addr;
1799 			err = 0;
1800 			break;
1801 		}
1802 	}
1803 	return err;
1804 }
1805 
1806 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1807 		    u32 banned_flags)
1808 {
1809 	struct inet6_dev *idev;
1810 	int err = -EADDRNOTAVAIL;
1811 
1812 	rcu_read_lock();
1813 	idev = __in6_dev_get(dev);
1814 	if (idev) {
1815 		read_lock_bh(&idev->lock);
1816 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1817 		read_unlock_bh(&idev->lock);
1818 	}
1819 	rcu_read_unlock();
1820 	return err;
1821 }
1822 
1823 static int ipv6_count_addresses(const struct inet6_dev *idev)
1824 {
1825 	const struct inet6_ifaddr *ifp;
1826 	int cnt = 0;
1827 
1828 	rcu_read_lock();
1829 	list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1830 		cnt++;
1831 	rcu_read_unlock();
1832 	return cnt;
1833 }
1834 
1835 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1836 		  const struct net_device *dev, int strict)
1837 {
1838 	return ipv6_chk_addr_and_flags(net, addr, dev, !dev,
1839 				       strict, IFA_F_TENTATIVE);
1840 }
1841 EXPORT_SYMBOL(ipv6_chk_addr);
1842 
1843 /* device argument is used to find the L3 domain of interest. If
1844  * skip_dev_check is set, then the ifp device is not checked against
1845  * the passed in dev argument. So the 2 cases for addresses checks are:
1846  *   1. does the address exist in the L3 domain that dev is part of
1847  *      (skip_dev_check = true), or
1848  *
1849  *   2. does the address exist on the specific device
1850  *      (skip_dev_check = false)
1851  */
1852 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1853 			    const struct net_device *dev, bool skip_dev_check,
1854 			    int strict, u32 banned_flags)
1855 {
1856 	unsigned int hash = inet6_addr_hash(net, addr);
1857 	const struct net_device *l3mdev;
1858 	struct inet6_ifaddr *ifp;
1859 	u32 ifp_flags;
1860 
1861 	rcu_read_lock();
1862 
1863 	l3mdev = l3mdev_master_dev_rcu(dev);
1864 	if (skip_dev_check)
1865 		dev = NULL;
1866 
1867 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1868 		if (!net_eq(dev_net(ifp->idev->dev), net))
1869 			continue;
1870 
1871 		if (l3mdev_master_dev_rcu(ifp->idev->dev) != l3mdev)
1872 			continue;
1873 
1874 		/* Decouple optimistic from tentative for evaluation here.
1875 		 * Ban optimistic addresses explicitly, when required.
1876 		 */
1877 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1878 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1879 			    : ifp->flags;
1880 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1881 		    !(ifp_flags&banned_flags) &&
1882 		    (!dev || ifp->idev->dev == dev ||
1883 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1884 			rcu_read_unlock();
1885 			return 1;
1886 		}
1887 	}
1888 
1889 	rcu_read_unlock();
1890 	return 0;
1891 }
1892 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
1893 
1894 
1895 /* Compares an address/prefix_len with addresses on device @dev.
1896  * If one is found it returns true.
1897  */
1898 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1899 	const unsigned int prefix_len, struct net_device *dev)
1900 {
1901 	const struct inet6_ifaddr *ifa;
1902 	const struct inet6_dev *idev;
1903 	bool ret = false;
1904 
1905 	rcu_read_lock();
1906 	idev = __in6_dev_get(dev);
1907 	if (idev) {
1908 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1909 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1910 			if (ret)
1911 				break;
1912 		}
1913 	}
1914 	rcu_read_unlock();
1915 
1916 	return ret;
1917 }
1918 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1919 
1920 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1921 {
1922 	const struct inet6_ifaddr *ifa;
1923 	const struct inet6_dev *idev;
1924 	int	onlink;
1925 
1926 	onlink = 0;
1927 	rcu_read_lock();
1928 	idev = __in6_dev_get(dev);
1929 	if (idev) {
1930 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1931 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1932 						   ifa->prefix_len);
1933 			if (onlink)
1934 				break;
1935 		}
1936 	}
1937 	rcu_read_unlock();
1938 	return onlink;
1939 }
1940 EXPORT_SYMBOL(ipv6_chk_prefix);
1941 
1942 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1943 				     struct net_device *dev, int strict)
1944 {
1945 	unsigned int hash = inet6_addr_hash(net, addr);
1946 	struct inet6_ifaddr *ifp, *result = NULL;
1947 
1948 	rcu_read_lock();
1949 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1950 		if (!net_eq(dev_net(ifp->idev->dev), net))
1951 			continue;
1952 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1953 			if (!dev || ifp->idev->dev == dev ||
1954 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1955 				result = ifp;
1956 				in6_ifa_hold(ifp);
1957 				break;
1958 			}
1959 		}
1960 	}
1961 	rcu_read_unlock();
1962 
1963 	return result;
1964 }
1965 
1966 /* Gets referenced address, destroys ifaddr */
1967 
1968 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1969 {
1970 	if (dad_failed)
1971 		ifp->flags |= IFA_F_DADFAILED;
1972 
1973 	if (ifp->flags&IFA_F_TEMPORARY) {
1974 		struct inet6_ifaddr *ifpub;
1975 		spin_lock_bh(&ifp->lock);
1976 		ifpub = ifp->ifpub;
1977 		if (ifpub) {
1978 			in6_ifa_hold(ifpub);
1979 			spin_unlock_bh(&ifp->lock);
1980 			ipv6_create_tempaddr(ifpub, ifp, true);
1981 			in6_ifa_put(ifpub);
1982 		} else {
1983 			spin_unlock_bh(&ifp->lock);
1984 		}
1985 		ipv6_del_addr(ifp);
1986 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
1987 		spin_lock_bh(&ifp->lock);
1988 		addrconf_del_dad_work(ifp);
1989 		ifp->flags |= IFA_F_TENTATIVE;
1990 		if (dad_failed)
1991 			ifp->flags &= ~IFA_F_OPTIMISTIC;
1992 		spin_unlock_bh(&ifp->lock);
1993 		if (dad_failed)
1994 			ipv6_ifa_notify(0, ifp);
1995 		in6_ifa_put(ifp);
1996 	} else {
1997 		ipv6_del_addr(ifp);
1998 	}
1999 }
2000 
2001 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
2002 {
2003 	int err = -ENOENT;
2004 
2005 	spin_lock_bh(&ifp->lock);
2006 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
2007 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
2008 		err = 0;
2009 	}
2010 	spin_unlock_bh(&ifp->lock);
2011 
2012 	return err;
2013 }
2014 
2015 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp)
2016 {
2017 	struct inet6_dev *idev = ifp->idev;
2018 	struct net *net = dev_net(ifp->idev->dev);
2019 
2020 	if (addrconf_dad_end(ifp)) {
2021 		in6_ifa_put(ifp);
2022 		return;
2023 	}
2024 
2025 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c used by %pM detected!\n",
2026 			     ifp->idev->dev->name, &ifp->addr, eth_hdr(skb)->h_source);
2027 
2028 	spin_lock_bh(&ifp->lock);
2029 
2030 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2031 		struct in6_addr new_addr;
2032 		struct inet6_ifaddr *ifp2;
2033 		int retries = ifp->stable_privacy_retry + 1;
2034 		struct ifa6_config cfg = {
2035 			.pfx = &new_addr,
2036 			.plen = ifp->prefix_len,
2037 			.ifa_flags = ifp->flags,
2038 			.valid_lft = ifp->valid_lft,
2039 			.preferred_lft = ifp->prefered_lft,
2040 			.scope = ifp->scope,
2041 		};
2042 
2043 		if (retries > net->ipv6.sysctl.idgen_retries) {
2044 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2045 					     ifp->idev->dev->name);
2046 			goto errdad;
2047 		}
2048 
2049 		new_addr = ifp->addr;
2050 		if (ipv6_generate_stable_address(&new_addr, retries,
2051 						 idev))
2052 			goto errdad;
2053 
2054 		spin_unlock_bh(&ifp->lock);
2055 
2056 		if (idev->cnf.max_addresses &&
2057 		    ipv6_count_addresses(idev) >=
2058 		    idev->cnf.max_addresses)
2059 			goto lock_errdad;
2060 
2061 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2062 				     ifp->idev->dev->name);
2063 
2064 		ifp2 = ipv6_add_addr(idev, &cfg, false, NULL);
2065 		if (IS_ERR(ifp2))
2066 			goto lock_errdad;
2067 
2068 		spin_lock_bh(&ifp2->lock);
2069 		ifp2->stable_privacy_retry = retries;
2070 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2071 		spin_unlock_bh(&ifp2->lock);
2072 
2073 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2074 		in6_ifa_put(ifp2);
2075 lock_errdad:
2076 		spin_lock_bh(&ifp->lock);
2077 	}
2078 
2079 errdad:
2080 	/* transition from _POSTDAD to _ERRDAD */
2081 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2082 	spin_unlock_bh(&ifp->lock);
2083 
2084 	addrconf_mod_dad_work(ifp, 0);
2085 	in6_ifa_put(ifp);
2086 }
2087 
2088 /* Join to solicited addr multicast group.
2089  * caller must hold RTNL */
2090 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2091 {
2092 	struct in6_addr maddr;
2093 
2094 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2095 		return;
2096 
2097 	addrconf_addr_solict_mult(addr, &maddr);
2098 	ipv6_dev_mc_inc(dev, &maddr);
2099 }
2100 
2101 /* caller must hold RTNL */
2102 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2103 {
2104 	struct in6_addr maddr;
2105 
2106 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2107 		return;
2108 
2109 	addrconf_addr_solict_mult(addr, &maddr);
2110 	__ipv6_dev_mc_dec(idev, &maddr);
2111 }
2112 
2113 /* caller must hold RTNL */
2114 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2115 {
2116 	struct in6_addr addr;
2117 
2118 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2119 		return;
2120 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2121 	if (ipv6_addr_any(&addr))
2122 		return;
2123 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2124 }
2125 
2126 /* caller must hold RTNL */
2127 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2128 {
2129 	struct in6_addr addr;
2130 
2131 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2132 		return;
2133 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2134 	if (ipv6_addr_any(&addr))
2135 		return;
2136 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2137 }
2138 
2139 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2140 {
2141 	switch (dev->addr_len) {
2142 	case ETH_ALEN:
2143 		memcpy(eui, dev->dev_addr, 3);
2144 		eui[3] = 0xFF;
2145 		eui[4] = 0xFE;
2146 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2147 		break;
2148 	case EUI64_ADDR_LEN:
2149 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2150 		eui[0] ^= 2;
2151 		break;
2152 	default:
2153 		return -1;
2154 	}
2155 
2156 	return 0;
2157 }
2158 
2159 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2160 {
2161 	union fwnet_hwaddr *ha;
2162 
2163 	if (dev->addr_len != FWNET_ALEN)
2164 		return -1;
2165 
2166 	ha = (union fwnet_hwaddr *)dev->dev_addr;
2167 
2168 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2169 	eui[0] ^= 2;
2170 	return 0;
2171 }
2172 
2173 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2174 {
2175 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2176 	if (dev->addr_len != ARCNET_ALEN)
2177 		return -1;
2178 	memset(eui, 0, 7);
2179 	eui[7] = *(u8 *)dev->dev_addr;
2180 	return 0;
2181 }
2182 
2183 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2184 {
2185 	if (dev->addr_len != INFINIBAND_ALEN)
2186 		return -1;
2187 	memcpy(eui, dev->dev_addr + 12, 8);
2188 	eui[0] |= 2;
2189 	return 0;
2190 }
2191 
2192 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2193 {
2194 	if (addr == 0)
2195 		return -1;
2196 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2197 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2198 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2199 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2200 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2201 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2202 	eui[1] = 0;
2203 	eui[2] = 0x5E;
2204 	eui[3] = 0xFE;
2205 	memcpy(eui + 4, &addr, 4);
2206 	return 0;
2207 }
2208 
2209 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2210 {
2211 	if (dev->priv_flags & IFF_ISATAP)
2212 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2213 	return -1;
2214 }
2215 
2216 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2217 {
2218 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2219 }
2220 
2221 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2222 {
2223 	memcpy(eui, dev->perm_addr, 3);
2224 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2225 	eui[3] = 0xFF;
2226 	eui[4] = 0xFE;
2227 	eui[0] ^= 2;
2228 	return 0;
2229 }
2230 
2231 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2232 {
2233 	switch (dev->type) {
2234 	case ARPHRD_ETHER:
2235 	case ARPHRD_FDDI:
2236 		return addrconf_ifid_eui48(eui, dev);
2237 	case ARPHRD_ARCNET:
2238 		return addrconf_ifid_arcnet(eui, dev);
2239 	case ARPHRD_INFINIBAND:
2240 		return addrconf_ifid_infiniband(eui, dev);
2241 	case ARPHRD_SIT:
2242 		return addrconf_ifid_sit(eui, dev);
2243 	case ARPHRD_IPGRE:
2244 	case ARPHRD_TUNNEL:
2245 		return addrconf_ifid_gre(eui, dev);
2246 	case ARPHRD_6LOWPAN:
2247 		return addrconf_ifid_6lowpan(eui, dev);
2248 	case ARPHRD_IEEE1394:
2249 		return addrconf_ifid_ieee1394(eui, dev);
2250 	case ARPHRD_TUNNEL6:
2251 	case ARPHRD_IP6GRE:
2252 	case ARPHRD_RAWIP:
2253 		return addrconf_ifid_ip6tnl(eui, dev);
2254 	}
2255 	return -1;
2256 }
2257 
2258 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2259 {
2260 	int err = -1;
2261 	struct inet6_ifaddr *ifp;
2262 
2263 	read_lock_bh(&idev->lock);
2264 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2265 		if (ifp->scope > IFA_LINK)
2266 			break;
2267 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2268 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2269 			err = 0;
2270 			break;
2271 		}
2272 	}
2273 	read_unlock_bh(&idev->lock);
2274 	return err;
2275 }
2276 
2277 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
2278 static void ipv6_regen_rndid(struct inet6_dev *idev)
2279 {
2280 regen:
2281 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
2282 	idev->rndid[0] &= ~0x02;
2283 
2284 	/*
2285 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
2286 	 * check if generated address is not inappropriate
2287 	 *
2288 	 *  - Reserved subnet anycast (RFC 2526)
2289 	 *	11111101 11....11 1xxxxxxx
2290 	 *  - ISATAP (RFC4214) 6.1
2291 	 *	00-00-5E-FE-xx-xx-xx-xx
2292 	 *  - value 0
2293 	 *  - XXX: already assigned to an address on the device
2294 	 */
2295 	if (idev->rndid[0] == 0xfd &&
2296 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
2297 	    (idev->rndid[7]&0x80))
2298 		goto regen;
2299 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
2300 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
2301 			goto regen;
2302 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
2303 			goto regen;
2304 	}
2305 }
2306 
2307 static void  ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
2308 {
2309 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
2310 		ipv6_regen_rndid(idev);
2311 }
2312 
2313 /*
2314  *	Add prefix route.
2315  */
2316 
2317 static void
2318 addrconf_prefix_route(struct in6_addr *pfx, int plen, u32 metric,
2319 		      struct net_device *dev, unsigned long expires,
2320 		      u32 flags, gfp_t gfp_flags)
2321 {
2322 	struct fib6_config cfg = {
2323 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2324 		.fc_metric = metric ? : IP6_RT_PRIO_ADDRCONF,
2325 		.fc_ifindex = dev->ifindex,
2326 		.fc_expires = expires,
2327 		.fc_dst_len = plen,
2328 		.fc_flags = RTF_UP | flags,
2329 		.fc_nlinfo.nl_net = dev_net(dev),
2330 		.fc_protocol = RTPROT_KERNEL,
2331 		.fc_type = RTN_UNICAST,
2332 	};
2333 
2334 	cfg.fc_dst = *pfx;
2335 
2336 	/* Prevent useless cloning on PtP SIT.
2337 	   This thing is done here expecting that the whole
2338 	   class of non-broadcast devices need not cloning.
2339 	 */
2340 #if IS_ENABLED(CONFIG_IPV6_SIT)
2341 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2342 		cfg.fc_flags |= RTF_NONEXTHOP;
2343 #endif
2344 
2345 	ip6_route_add(&cfg, gfp_flags, NULL);
2346 }
2347 
2348 
2349 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2350 						  int plen,
2351 						  const struct net_device *dev,
2352 						  u32 flags, u32 noflags)
2353 {
2354 	struct fib6_node *fn;
2355 	struct fib6_info *rt = NULL;
2356 	struct fib6_table *table;
2357 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2358 
2359 	table = fib6_get_table(dev_net(dev), tb_id);
2360 	if (!table)
2361 		return NULL;
2362 
2363 	rcu_read_lock();
2364 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2365 	if (!fn)
2366 		goto out;
2367 
2368 	for_each_fib6_node_rt_rcu(fn) {
2369 		if (rt->fib6_nh.nh_dev->ifindex != dev->ifindex)
2370 			continue;
2371 		if ((rt->fib6_flags & flags) != flags)
2372 			continue;
2373 		if ((rt->fib6_flags & noflags) != 0)
2374 			continue;
2375 		if (!fib6_info_hold_safe(rt))
2376 			continue;
2377 		break;
2378 	}
2379 out:
2380 	rcu_read_unlock();
2381 	return rt;
2382 }
2383 
2384 
2385 /* Create "default" multicast route to the interface */
2386 
2387 static void addrconf_add_mroute(struct net_device *dev)
2388 {
2389 	struct fib6_config cfg = {
2390 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2391 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2392 		.fc_ifindex = dev->ifindex,
2393 		.fc_dst_len = 8,
2394 		.fc_flags = RTF_UP,
2395 		.fc_type = RTN_UNICAST,
2396 		.fc_nlinfo.nl_net = dev_net(dev),
2397 	};
2398 
2399 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2400 
2401 	ip6_route_add(&cfg, GFP_KERNEL, NULL);
2402 }
2403 
2404 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2405 {
2406 	struct inet6_dev *idev;
2407 
2408 	ASSERT_RTNL();
2409 
2410 	idev = ipv6_find_idev(dev);
2411 	if (!idev)
2412 		return ERR_PTR(-ENOBUFS);
2413 
2414 	if (idev->cnf.disable_ipv6)
2415 		return ERR_PTR(-EACCES);
2416 
2417 	/* Add default multicast route */
2418 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2419 		addrconf_add_mroute(dev);
2420 
2421 	return idev;
2422 }
2423 
2424 static void manage_tempaddrs(struct inet6_dev *idev,
2425 			     struct inet6_ifaddr *ifp,
2426 			     __u32 valid_lft, __u32 prefered_lft,
2427 			     bool create, unsigned long now)
2428 {
2429 	u32 flags;
2430 	struct inet6_ifaddr *ift;
2431 
2432 	read_lock_bh(&idev->lock);
2433 	/* update all temporary addresses in the list */
2434 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2435 		int age, max_valid, max_prefered;
2436 
2437 		if (ifp != ift->ifpub)
2438 			continue;
2439 
2440 		/* RFC 4941 section 3.3:
2441 		 * If a received option will extend the lifetime of a public
2442 		 * address, the lifetimes of temporary addresses should
2443 		 * be extended, subject to the overall constraint that no
2444 		 * temporary addresses should ever remain "valid" or "preferred"
2445 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2446 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2447 		 */
2448 		age = (now - ift->cstamp) / HZ;
2449 		max_valid = idev->cnf.temp_valid_lft - age;
2450 		if (max_valid < 0)
2451 			max_valid = 0;
2452 
2453 		max_prefered = idev->cnf.temp_prefered_lft -
2454 			       idev->desync_factor - age;
2455 		if (max_prefered < 0)
2456 			max_prefered = 0;
2457 
2458 		if (valid_lft > max_valid)
2459 			valid_lft = max_valid;
2460 
2461 		if (prefered_lft > max_prefered)
2462 			prefered_lft = max_prefered;
2463 
2464 		spin_lock(&ift->lock);
2465 		flags = ift->flags;
2466 		ift->valid_lft = valid_lft;
2467 		ift->prefered_lft = prefered_lft;
2468 		ift->tstamp = now;
2469 		if (prefered_lft > 0)
2470 			ift->flags &= ~IFA_F_DEPRECATED;
2471 
2472 		spin_unlock(&ift->lock);
2473 		if (!(flags&IFA_F_TENTATIVE))
2474 			ipv6_ifa_notify(0, ift);
2475 	}
2476 
2477 	if ((create || list_empty(&idev->tempaddr_list)) &&
2478 	    idev->cnf.use_tempaddr > 0) {
2479 		/* When a new public address is created as described
2480 		 * in [ADDRCONF], also create a new temporary address.
2481 		 * Also create a temporary address if it's enabled but
2482 		 * no temporary address currently exists.
2483 		 */
2484 		read_unlock_bh(&idev->lock);
2485 		ipv6_create_tempaddr(ifp, NULL, false);
2486 	} else {
2487 		read_unlock_bh(&idev->lock);
2488 	}
2489 }
2490 
2491 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2492 {
2493 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2494 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2495 }
2496 
2497 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2498 				 const struct prefix_info *pinfo,
2499 				 struct inet6_dev *in6_dev,
2500 				 const struct in6_addr *addr, int addr_type,
2501 				 u32 addr_flags, bool sllao, bool tokenized,
2502 				 __u32 valid_lft, u32 prefered_lft)
2503 {
2504 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2505 	int create = 0, update_lft = 0;
2506 
2507 	if (!ifp && valid_lft) {
2508 		int max_addresses = in6_dev->cnf.max_addresses;
2509 		struct ifa6_config cfg = {
2510 			.pfx = addr,
2511 			.plen = pinfo->prefix_len,
2512 			.ifa_flags = addr_flags,
2513 			.valid_lft = valid_lft,
2514 			.preferred_lft = prefered_lft,
2515 			.scope = addr_type & IPV6_ADDR_SCOPE_MASK,
2516 		};
2517 
2518 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2519 		if ((net->ipv6.devconf_all->optimistic_dad ||
2520 		     in6_dev->cnf.optimistic_dad) &&
2521 		    !net->ipv6.devconf_all->forwarding && sllao)
2522 			cfg.ifa_flags |= IFA_F_OPTIMISTIC;
2523 #endif
2524 
2525 		/* Do not allow to create too much of autoconfigured
2526 		 * addresses; this would be too easy way to crash kernel.
2527 		 */
2528 		if (!max_addresses ||
2529 		    ipv6_count_addresses(in6_dev) < max_addresses)
2530 			ifp = ipv6_add_addr(in6_dev, &cfg, false, NULL);
2531 
2532 		if (IS_ERR_OR_NULL(ifp))
2533 			return -1;
2534 
2535 		create = 1;
2536 		spin_lock_bh(&ifp->lock);
2537 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2538 		ifp->cstamp = jiffies;
2539 		ifp->tokenized = tokenized;
2540 		spin_unlock_bh(&ifp->lock);
2541 		addrconf_dad_start(ifp);
2542 	}
2543 
2544 	if (ifp) {
2545 		u32 flags;
2546 		unsigned long now;
2547 		u32 stored_lft;
2548 
2549 		/* update lifetime (RFC2462 5.5.3 e) */
2550 		spin_lock_bh(&ifp->lock);
2551 		now = jiffies;
2552 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2553 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2554 		else
2555 			stored_lft = 0;
2556 		if (!create && stored_lft) {
2557 			const u32 minimum_lft = min_t(u32,
2558 				stored_lft, MIN_VALID_LIFETIME);
2559 			valid_lft = max(valid_lft, minimum_lft);
2560 
2561 			/* RFC4862 Section 5.5.3e:
2562 			 * "Note that the preferred lifetime of the
2563 			 *  corresponding address is always reset to
2564 			 *  the Preferred Lifetime in the received
2565 			 *  Prefix Information option, regardless of
2566 			 *  whether the valid lifetime is also reset or
2567 			 *  ignored."
2568 			 *
2569 			 * So we should always update prefered_lft here.
2570 			 */
2571 			update_lft = 1;
2572 		}
2573 
2574 		if (update_lft) {
2575 			ifp->valid_lft = valid_lft;
2576 			ifp->prefered_lft = prefered_lft;
2577 			ifp->tstamp = now;
2578 			flags = ifp->flags;
2579 			ifp->flags &= ~IFA_F_DEPRECATED;
2580 			spin_unlock_bh(&ifp->lock);
2581 
2582 			if (!(flags&IFA_F_TENTATIVE))
2583 				ipv6_ifa_notify(0, ifp);
2584 		} else
2585 			spin_unlock_bh(&ifp->lock);
2586 
2587 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2588 				 create, now);
2589 
2590 		in6_ifa_put(ifp);
2591 		addrconf_verify();
2592 	}
2593 
2594 	return 0;
2595 }
2596 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2597 
2598 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2599 {
2600 	struct prefix_info *pinfo;
2601 	__u32 valid_lft;
2602 	__u32 prefered_lft;
2603 	int addr_type, err;
2604 	u32 addr_flags = 0;
2605 	struct inet6_dev *in6_dev;
2606 	struct net *net = dev_net(dev);
2607 
2608 	pinfo = (struct prefix_info *) opt;
2609 
2610 	if (len < sizeof(struct prefix_info)) {
2611 		netdev_dbg(dev, "addrconf: prefix option too short\n");
2612 		return;
2613 	}
2614 
2615 	/*
2616 	 *	Validation checks ([ADDRCONF], page 19)
2617 	 */
2618 
2619 	addr_type = ipv6_addr_type(&pinfo->prefix);
2620 
2621 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2622 		return;
2623 
2624 	valid_lft = ntohl(pinfo->valid);
2625 	prefered_lft = ntohl(pinfo->prefered);
2626 
2627 	if (prefered_lft > valid_lft) {
2628 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2629 		return;
2630 	}
2631 
2632 	in6_dev = in6_dev_get(dev);
2633 
2634 	if (!in6_dev) {
2635 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2636 				    dev->name);
2637 		return;
2638 	}
2639 
2640 	/*
2641 	 *	Two things going on here:
2642 	 *	1) Add routes for on-link prefixes
2643 	 *	2) Configure prefixes with the auto flag set
2644 	 */
2645 
2646 	if (pinfo->onlink) {
2647 		struct fib6_info *rt;
2648 		unsigned long rt_expires;
2649 
2650 		/* Avoid arithmetic overflow. Really, we could
2651 		 * save rt_expires in seconds, likely valid_lft,
2652 		 * but it would require division in fib gc, that it
2653 		 * not good.
2654 		 */
2655 		if (HZ > USER_HZ)
2656 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2657 		else
2658 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2659 
2660 		if (addrconf_finite_timeout(rt_expires))
2661 			rt_expires *= HZ;
2662 
2663 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2664 					       pinfo->prefix_len,
2665 					       dev,
2666 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2667 					       RTF_GATEWAY | RTF_DEFAULT);
2668 
2669 		if (rt) {
2670 			/* Autoconf prefix route */
2671 			if (valid_lft == 0) {
2672 				ip6_del_rt(net, rt);
2673 				rt = NULL;
2674 			} else if (addrconf_finite_timeout(rt_expires)) {
2675 				/* not infinity */
2676 				fib6_set_expires(rt, jiffies + rt_expires);
2677 			} else {
2678 				fib6_clean_expires(rt);
2679 			}
2680 		} else if (valid_lft) {
2681 			clock_t expires = 0;
2682 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2683 			if (addrconf_finite_timeout(rt_expires)) {
2684 				/* not infinity */
2685 				flags |= RTF_EXPIRES;
2686 				expires = jiffies_to_clock_t(rt_expires);
2687 			}
2688 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2689 					      0, dev, expires, flags,
2690 					      GFP_ATOMIC);
2691 		}
2692 		fib6_info_release(rt);
2693 	}
2694 
2695 	/* Try to figure out our local address for this prefix */
2696 
2697 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2698 		struct in6_addr addr;
2699 		bool tokenized = false, dev_addr_generated = false;
2700 
2701 		if (pinfo->prefix_len == 64) {
2702 			memcpy(&addr, &pinfo->prefix, 8);
2703 
2704 			if (!ipv6_addr_any(&in6_dev->token)) {
2705 				read_lock_bh(&in6_dev->lock);
2706 				memcpy(addr.s6_addr + 8,
2707 				       in6_dev->token.s6_addr + 8, 8);
2708 				read_unlock_bh(&in6_dev->lock);
2709 				tokenized = true;
2710 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2711 				   !ipv6_generate_stable_address(&addr, 0,
2712 								 in6_dev)) {
2713 				addr_flags |= IFA_F_STABLE_PRIVACY;
2714 				goto ok;
2715 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2716 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2717 				goto put;
2718 			} else {
2719 				dev_addr_generated = true;
2720 			}
2721 			goto ok;
2722 		}
2723 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2724 				    pinfo->prefix_len);
2725 		goto put;
2726 
2727 ok:
2728 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2729 						   &addr, addr_type,
2730 						   addr_flags, sllao,
2731 						   tokenized, valid_lft,
2732 						   prefered_lft);
2733 		if (err)
2734 			goto put;
2735 
2736 		/* Ignore error case here because previous prefix add addr was
2737 		 * successful which will be notified.
2738 		 */
2739 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2740 					      addr_type, addr_flags, sllao,
2741 					      tokenized, valid_lft,
2742 					      prefered_lft,
2743 					      dev_addr_generated);
2744 	}
2745 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2746 put:
2747 	in6_dev_put(in6_dev);
2748 }
2749 
2750 /*
2751  *	Set destination address.
2752  *	Special case for SIT interfaces where we create a new "virtual"
2753  *	device.
2754  */
2755 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2756 {
2757 	struct in6_ifreq ireq;
2758 	struct net_device *dev;
2759 	int err = -EINVAL;
2760 
2761 	rtnl_lock();
2762 
2763 	err = -EFAULT;
2764 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2765 		goto err_exit;
2766 
2767 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2768 
2769 	err = -ENODEV;
2770 	if (!dev)
2771 		goto err_exit;
2772 
2773 #if IS_ENABLED(CONFIG_IPV6_SIT)
2774 	if (dev->type == ARPHRD_SIT) {
2775 		const struct net_device_ops *ops = dev->netdev_ops;
2776 		struct ifreq ifr;
2777 		struct ip_tunnel_parm p;
2778 
2779 		err = -EADDRNOTAVAIL;
2780 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2781 			goto err_exit;
2782 
2783 		memset(&p, 0, sizeof(p));
2784 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2785 		p.iph.saddr = 0;
2786 		p.iph.version = 4;
2787 		p.iph.ihl = 5;
2788 		p.iph.protocol = IPPROTO_IPV6;
2789 		p.iph.ttl = 64;
2790 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2791 
2792 		if (ops->ndo_do_ioctl) {
2793 			mm_segment_t oldfs = get_fs();
2794 
2795 			set_fs(KERNEL_DS);
2796 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2797 			set_fs(oldfs);
2798 		} else
2799 			err = -EOPNOTSUPP;
2800 
2801 		if (err == 0) {
2802 			err = -ENOBUFS;
2803 			dev = __dev_get_by_name(net, p.name);
2804 			if (!dev)
2805 				goto err_exit;
2806 			err = dev_open(dev);
2807 		}
2808 	}
2809 #endif
2810 
2811 err_exit:
2812 	rtnl_unlock();
2813 	return err;
2814 }
2815 
2816 static int ipv6_mc_config(struct sock *sk, bool join,
2817 			  const struct in6_addr *addr, int ifindex)
2818 {
2819 	int ret;
2820 
2821 	ASSERT_RTNL();
2822 
2823 	lock_sock(sk);
2824 	if (join)
2825 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2826 	else
2827 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2828 	release_sock(sk);
2829 
2830 	return ret;
2831 }
2832 
2833 /*
2834  *	Manual configuration of address on an interface
2835  */
2836 static int inet6_addr_add(struct net *net, int ifindex,
2837 			  struct ifa6_config *cfg,
2838 			  struct netlink_ext_ack *extack)
2839 {
2840 	struct inet6_ifaddr *ifp;
2841 	struct inet6_dev *idev;
2842 	struct net_device *dev;
2843 	unsigned long timeout;
2844 	clock_t expires;
2845 	u32 flags;
2846 
2847 	ASSERT_RTNL();
2848 
2849 	if (cfg->plen > 128)
2850 		return -EINVAL;
2851 
2852 	/* check the lifetime */
2853 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
2854 		return -EINVAL;
2855 
2856 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR && cfg->plen != 64)
2857 		return -EINVAL;
2858 
2859 	dev = __dev_get_by_index(net, ifindex);
2860 	if (!dev)
2861 		return -ENODEV;
2862 
2863 	idev = addrconf_add_dev(dev);
2864 	if (IS_ERR(idev))
2865 		return PTR_ERR(idev);
2866 
2867 	if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2868 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2869 					 true, cfg->pfx, ifindex);
2870 
2871 		if (ret < 0)
2872 			return ret;
2873 	}
2874 
2875 	cfg->scope = ipv6_addr_scope(cfg->pfx);
2876 
2877 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
2878 	if (addrconf_finite_timeout(timeout)) {
2879 		expires = jiffies_to_clock_t(timeout * HZ);
2880 		cfg->valid_lft = timeout;
2881 		flags = RTF_EXPIRES;
2882 	} else {
2883 		expires = 0;
2884 		flags = 0;
2885 		cfg->ifa_flags |= IFA_F_PERMANENT;
2886 	}
2887 
2888 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
2889 	if (addrconf_finite_timeout(timeout)) {
2890 		if (timeout == 0)
2891 			cfg->ifa_flags |= IFA_F_DEPRECATED;
2892 		cfg->preferred_lft = timeout;
2893 	}
2894 
2895 	ifp = ipv6_add_addr(idev, cfg, true, extack);
2896 	if (!IS_ERR(ifp)) {
2897 		if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
2898 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
2899 					      ifp->rt_priority, dev, expires,
2900 					      flags, GFP_KERNEL);
2901 		}
2902 
2903 		/* Send a netlink notification if DAD is enabled and
2904 		 * optimistic flag is not set
2905 		 */
2906 		if (!(ifp->flags & (IFA_F_OPTIMISTIC | IFA_F_NODAD)))
2907 			ipv6_ifa_notify(0, ifp);
2908 		/*
2909 		 * Note that section 3.1 of RFC 4429 indicates
2910 		 * that the Optimistic flag should not be set for
2911 		 * manually configured addresses
2912 		 */
2913 		addrconf_dad_start(ifp);
2914 		if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR)
2915 			manage_tempaddrs(idev, ifp, cfg->valid_lft,
2916 					 cfg->preferred_lft, true, jiffies);
2917 		in6_ifa_put(ifp);
2918 		addrconf_verify_rtnl();
2919 		return 0;
2920 	} else if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2921 		ipv6_mc_config(net->ipv6.mc_autojoin_sk, false,
2922 			       cfg->pfx, ifindex);
2923 	}
2924 
2925 	return PTR_ERR(ifp);
2926 }
2927 
2928 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
2929 			  const struct in6_addr *pfx, unsigned int plen)
2930 {
2931 	struct inet6_ifaddr *ifp;
2932 	struct inet6_dev *idev;
2933 	struct net_device *dev;
2934 
2935 	if (plen > 128)
2936 		return -EINVAL;
2937 
2938 	dev = __dev_get_by_index(net, ifindex);
2939 	if (!dev)
2940 		return -ENODEV;
2941 
2942 	idev = __in6_dev_get(dev);
2943 	if (!idev)
2944 		return -ENXIO;
2945 
2946 	read_lock_bh(&idev->lock);
2947 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2948 		if (ifp->prefix_len == plen &&
2949 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2950 			in6_ifa_hold(ifp);
2951 			read_unlock_bh(&idev->lock);
2952 
2953 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
2954 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
2955 				manage_tempaddrs(idev, ifp, 0, 0, false,
2956 						 jiffies);
2957 			ipv6_del_addr(ifp);
2958 			addrconf_verify_rtnl();
2959 			if (ipv6_addr_is_multicast(pfx)) {
2960 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2961 					       false, pfx, dev->ifindex);
2962 			}
2963 			return 0;
2964 		}
2965 	}
2966 	read_unlock_bh(&idev->lock);
2967 	return -EADDRNOTAVAIL;
2968 }
2969 
2970 
2971 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2972 {
2973 	struct ifa6_config cfg = {
2974 		.ifa_flags = IFA_F_PERMANENT,
2975 		.preferred_lft = INFINITY_LIFE_TIME,
2976 		.valid_lft = INFINITY_LIFE_TIME,
2977 	};
2978 	struct in6_ifreq ireq;
2979 	int err;
2980 
2981 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2982 		return -EPERM;
2983 
2984 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2985 		return -EFAULT;
2986 
2987 	cfg.pfx = &ireq.ifr6_addr;
2988 	cfg.plen = ireq.ifr6_prefixlen;
2989 
2990 	rtnl_lock();
2991 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &cfg, NULL);
2992 	rtnl_unlock();
2993 	return err;
2994 }
2995 
2996 int addrconf_del_ifaddr(struct net *net, void __user *arg)
2997 {
2998 	struct in6_ifreq ireq;
2999 	int err;
3000 
3001 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3002 		return -EPERM;
3003 
3004 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3005 		return -EFAULT;
3006 
3007 	rtnl_lock();
3008 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
3009 			     ireq.ifr6_prefixlen);
3010 	rtnl_unlock();
3011 	return err;
3012 }
3013 
3014 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
3015 		     int plen, int scope)
3016 {
3017 	struct inet6_ifaddr *ifp;
3018 	struct ifa6_config cfg = {
3019 		.pfx = addr,
3020 		.plen = plen,
3021 		.ifa_flags = IFA_F_PERMANENT,
3022 		.valid_lft = INFINITY_LIFE_TIME,
3023 		.preferred_lft = INFINITY_LIFE_TIME,
3024 		.scope = scope
3025 	};
3026 
3027 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3028 	if (!IS_ERR(ifp)) {
3029 		spin_lock_bh(&ifp->lock);
3030 		ifp->flags &= ~IFA_F_TENTATIVE;
3031 		spin_unlock_bh(&ifp->lock);
3032 		rt_genid_bump_ipv6(dev_net(idev->dev));
3033 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3034 		in6_ifa_put(ifp);
3035 	}
3036 }
3037 
3038 #if IS_ENABLED(CONFIG_IPV6_SIT)
3039 static void sit_add_v4_addrs(struct inet6_dev *idev)
3040 {
3041 	struct in6_addr addr;
3042 	struct net_device *dev;
3043 	struct net *net = dev_net(idev->dev);
3044 	int scope, plen;
3045 	u32 pflags = 0;
3046 
3047 	ASSERT_RTNL();
3048 
3049 	memset(&addr, 0, sizeof(struct in6_addr));
3050 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
3051 
3052 	if (idev->dev->flags&IFF_POINTOPOINT) {
3053 		addr.s6_addr32[0] = htonl(0xfe800000);
3054 		scope = IFA_LINK;
3055 		plen = 64;
3056 	} else {
3057 		scope = IPV6_ADDR_COMPATv4;
3058 		plen = 96;
3059 		pflags |= RTF_NONEXTHOP;
3060 	}
3061 
3062 	if (addr.s6_addr32[3]) {
3063 		add_addr(idev, &addr, plen, scope);
3064 		addrconf_prefix_route(&addr, plen, 0, idev->dev, 0, pflags,
3065 				      GFP_KERNEL);
3066 		return;
3067 	}
3068 
3069 	for_each_netdev(net, dev) {
3070 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3071 		if (in_dev && (dev->flags & IFF_UP)) {
3072 			struct in_ifaddr *ifa;
3073 
3074 			int flag = scope;
3075 
3076 			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
3077 
3078 				addr.s6_addr32[3] = ifa->ifa_local;
3079 
3080 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3081 					continue;
3082 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3083 					if (idev->dev->flags&IFF_POINTOPOINT)
3084 						continue;
3085 					flag |= IFA_HOST;
3086 				}
3087 
3088 				add_addr(idev, &addr, plen, flag);
3089 				addrconf_prefix_route(&addr, plen, 0, idev->dev,
3090 						      0, pflags, GFP_KERNEL);
3091 			}
3092 		}
3093 	}
3094 }
3095 #endif
3096 
3097 static void init_loopback(struct net_device *dev)
3098 {
3099 	struct inet6_dev  *idev;
3100 
3101 	/* ::1 */
3102 
3103 	ASSERT_RTNL();
3104 
3105 	idev = ipv6_find_idev(dev);
3106 	if (!idev) {
3107 		pr_debug("%s: add_dev failed\n", __func__);
3108 		return;
3109 	}
3110 
3111 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
3112 }
3113 
3114 void addrconf_add_linklocal(struct inet6_dev *idev,
3115 			    const struct in6_addr *addr, u32 flags)
3116 {
3117 	struct ifa6_config cfg = {
3118 		.pfx = addr,
3119 		.plen = 64,
3120 		.ifa_flags = flags | IFA_F_PERMANENT,
3121 		.valid_lft = INFINITY_LIFE_TIME,
3122 		.preferred_lft = INFINITY_LIFE_TIME,
3123 		.scope = IFA_LINK
3124 	};
3125 	struct inet6_ifaddr *ifp;
3126 
3127 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3128 	if ((dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad ||
3129 	     idev->cnf.optimistic_dad) &&
3130 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3131 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
3132 #endif
3133 
3134 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3135 	if (!IS_ERR(ifp)) {
3136 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, 0, idev->dev,
3137 				      0, 0, GFP_ATOMIC);
3138 		addrconf_dad_start(ifp);
3139 		in6_ifa_put(ifp);
3140 	}
3141 }
3142 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3143 
3144 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3145 {
3146 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3147 		return true;
3148 
3149 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3150 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3151 		return true;
3152 
3153 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3154 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3155 		return true;
3156 
3157 	return false;
3158 }
3159 
3160 static int ipv6_generate_stable_address(struct in6_addr *address,
3161 					u8 dad_count,
3162 					const struct inet6_dev *idev)
3163 {
3164 	static DEFINE_SPINLOCK(lock);
3165 	static __u32 digest[SHA_DIGEST_WORDS];
3166 	static __u32 workspace[SHA_WORKSPACE_WORDS];
3167 
3168 	static union {
3169 		char __data[SHA_MESSAGE_BYTES];
3170 		struct {
3171 			struct in6_addr secret;
3172 			__be32 prefix[2];
3173 			unsigned char hwaddr[MAX_ADDR_LEN];
3174 			u8 dad_count;
3175 		} __packed;
3176 	} data;
3177 
3178 	struct in6_addr secret;
3179 	struct in6_addr temp;
3180 	struct net *net = dev_net(idev->dev);
3181 
3182 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3183 
3184 	if (idev->cnf.stable_secret.initialized)
3185 		secret = idev->cnf.stable_secret.secret;
3186 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3187 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3188 	else
3189 		return -1;
3190 
3191 retry:
3192 	spin_lock_bh(&lock);
3193 
3194 	sha_init(digest);
3195 	memset(&data, 0, sizeof(data));
3196 	memset(workspace, 0, sizeof(workspace));
3197 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3198 	data.prefix[0] = address->s6_addr32[0];
3199 	data.prefix[1] = address->s6_addr32[1];
3200 	data.secret = secret;
3201 	data.dad_count = dad_count;
3202 
3203 	sha_transform(digest, data.__data, workspace);
3204 
3205 	temp = *address;
3206 	temp.s6_addr32[2] = (__force __be32)digest[0];
3207 	temp.s6_addr32[3] = (__force __be32)digest[1];
3208 
3209 	spin_unlock_bh(&lock);
3210 
3211 	if (ipv6_reserved_interfaceid(temp)) {
3212 		dad_count++;
3213 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3214 			return -1;
3215 		goto retry;
3216 	}
3217 
3218 	*address = temp;
3219 	return 0;
3220 }
3221 
3222 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3223 {
3224 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3225 
3226 	if (s->initialized)
3227 		return;
3228 	s = &idev->cnf.stable_secret;
3229 	get_random_bytes(&s->secret, sizeof(s->secret));
3230 	s->initialized = true;
3231 }
3232 
3233 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3234 {
3235 	struct in6_addr addr;
3236 
3237 	/* no link local addresses on L3 master devices */
3238 	if (netif_is_l3_master(idev->dev))
3239 		return;
3240 
3241 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3242 
3243 	switch (idev->cnf.addr_gen_mode) {
3244 	case IN6_ADDR_GEN_MODE_RANDOM:
3245 		ipv6_gen_mode_random_init(idev);
3246 		/* fallthrough */
3247 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3248 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3249 			addrconf_add_linklocal(idev, &addr,
3250 					       IFA_F_STABLE_PRIVACY);
3251 		else if (prefix_route)
3252 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3253 					      0, 0, GFP_KERNEL);
3254 		break;
3255 	case IN6_ADDR_GEN_MODE_EUI64:
3256 		/* addrconf_add_linklocal also adds a prefix_route and we
3257 		 * only need to care about prefix routes if ipv6_generate_eui64
3258 		 * couldn't generate one.
3259 		 */
3260 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3261 			addrconf_add_linklocal(idev, &addr, 0);
3262 		else if (prefix_route)
3263 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3264 					      0, 0, GFP_KERNEL);
3265 		break;
3266 	case IN6_ADDR_GEN_MODE_NONE:
3267 	default:
3268 		/* will not add any link local address */
3269 		break;
3270 	}
3271 }
3272 
3273 static void addrconf_dev_config(struct net_device *dev)
3274 {
3275 	struct inet6_dev *idev;
3276 
3277 	ASSERT_RTNL();
3278 
3279 	if ((dev->type != ARPHRD_ETHER) &&
3280 	    (dev->type != ARPHRD_FDDI) &&
3281 	    (dev->type != ARPHRD_ARCNET) &&
3282 	    (dev->type != ARPHRD_INFINIBAND) &&
3283 	    (dev->type != ARPHRD_IEEE1394) &&
3284 	    (dev->type != ARPHRD_TUNNEL6) &&
3285 	    (dev->type != ARPHRD_6LOWPAN) &&
3286 	    (dev->type != ARPHRD_IP6GRE) &&
3287 	    (dev->type != ARPHRD_IPGRE) &&
3288 	    (dev->type != ARPHRD_TUNNEL) &&
3289 	    (dev->type != ARPHRD_NONE) &&
3290 	    (dev->type != ARPHRD_RAWIP)) {
3291 		/* Alas, we support only Ethernet autoconfiguration. */
3292 		return;
3293 	}
3294 
3295 	idev = addrconf_add_dev(dev);
3296 	if (IS_ERR(idev))
3297 		return;
3298 
3299 	/* this device type has no EUI support */
3300 	if (dev->type == ARPHRD_NONE &&
3301 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3302 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_RANDOM;
3303 
3304 	addrconf_addr_gen(idev, false);
3305 }
3306 
3307 #if IS_ENABLED(CONFIG_IPV6_SIT)
3308 static void addrconf_sit_config(struct net_device *dev)
3309 {
3310 	struct inet6_dev *idev;
3311 
3312 	ASSERT_RTNL();
3313 
3314 	/*
3315 	 * Configure the tunnel with one of our IPv4
3316 	 * addresses... we should configure all of
3317 	 * our v4 addrs in the tunnel
3318 	 */
3319 
3320 	idev = ipv6_find_idev(dev);
3321 	if (!idev) {
3322 		pr_debug("%s: add_dev failed\n", __func__);
3323 		return;
3324 	}
3325 
3326 	if (dev->priv_flags & IFF_ISATAP) {
3327 		addrconf_addr_gen(idev, false);
3328 		return;
3329 	}
3330 
3331 	sit_add_v4_addrs(idev);
3332 
3333 	if (dev->flags&IFF_POINTOPOINT)
3334 		addrconf_add_mroute(dev);
3335 }
3336 #endif
3337 
3338 #if IS_ENABLED(CONFIG_NET_IPGRE)
3339 static void addrconf_gre_config(struct net_device *dev)
3340 {
3341 	struct inet6_dev *idev;
3342 
3343 	ASSERT_RTNL();
3344 
3345 	idev = ipv6_find_idev(dev);
3346 	if (!idev) {
3347 		pr_debug("%s: add_dev failed\n", __func__);
3348 		return;
3349 	}
3350 
3351 	addrconf_addr_gen(idev, true);
3352 	if (dev->flags & IFF_POINTOPOINT)
3353 		addrconf_add_mroute(dev);
3354 }
3355 #endif
3356 
3357 static int fixup_permanent_addr(struct net *net,
3358 				struct inet6_dev *idev,
3359 				struct inet6_ifaddr *ifp)
3360 {
3361 	/* !fib6_node means the host route was removed from the
3362 	 * FIB, for example, if 'lo' device is taken down. In that
3363 	 * case regenerate the host route.
3364 	 */
3365 	if (!ifp->rt || !ifp->rt->fib6_node) {
3366 		struct fib6_info *f6i, *prev;
3367 
3368 		f6i = addrconf_f6i_alloc(net, idev, &ifp->addr, false,
3369 					 GFP_ATOMIC);
3370 		if (IS_ERR(f6i))
3371 			return PTR_ERR(f6i);
3372 
3373 		/* ifp->rt can be accessed outside of rtnl */
3374 		spin_lock(&ifp->lock);
3375 		prev = ifp->rt;
3376 		ifp->rt = f6i;
3377 		spin_unlock(&ifp->lock);
3378 
3379 		fib6_info_release(prev);
3380 	}
3381 
3382 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3383 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3384 				      ifp->rt_priority, idev->dev, 0, 0,
3385 				      GFP_ATOMIC);
3386 	}
3387 
3388 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3389 		addrconf_dad_start(ifp);
3390 
3391 	return 0;
3392 }
3393 
3394 static void addrconf_permanent_addr(struct net *net, struct net_device *dev)
3395 {
3396 	struct inet6_ifaddr *ifp, *tmp;
3397 	struct inet6_dev *idev;
3398 
3399 	idev = __in6_dev_get(dev);
3400 	if (!idev)
3401 		return;
3402 
3403 	write_lock_bh(&idev->lock);
3404 
3405 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3406 		if ((ifp->flags & IFA_F_PERMANENT) &&
3407 		    fixup_permanent_addr(net, idev, ifp) < 0) {
3408 			write_unlock_bh(&idev->lock);
3409 			in6_ifa_hold(ifp);
3410 			ipv6_del_addr(ifp);
3411 			write_lock_bh(&idev->lock);
3412 
3413 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3414 					     idev->dev->name, &ifp->addr);
3415 		}
3416 	}
3417 
3418 	write_unlock_bh(&idev->lock);
3419 }
3420 
3421 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3422 			   void *ptr)
3423 {
3424 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3425 	struct netdev_notifier_changeupper_info *info;
3426 	struct inet6_dev *idev = __in6_dev_get(dev);
3427 	struct net *net = dev_net(dev);
3428 	int run_pending = 0;
3429 	int err;
3430 
3431 	switch (event) {
3432 	case NETDEV_REGISTER:
3433 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3434 			idev = ipv6_add_dev(dev);
3435 			if (IS_ERR(idev))
3436 				return notifier_from_errno(PTR_ERR(idev));
3437 		}
3438 		break;
3439 
3440 	case NETDEV_CHANGEMTU:
3441 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3442 		if (dev->mtu < IPV6_MIN_MTU) {
3443 			addrconf_ifdown(dev, dev != net->loopback_dev);
3444 			break;
3445 		}
3446 
3447 		if (idev) {
3448 			rt6_mtu_change(dev, dev->mtu);
3449 			idev->cnf.mtu6 = dev->mtu;
3450 			break;
3451 		}
3452 
3453 		/* allocate new idev */
3454 		idev = ipv6_add_dev(dev);
3455 		if (IS_ERR(idev))
3456 			break;
3457 
3458 		/* device is still not ready */
3459 		if (!(idev->if_flags & IF_READY))
3460 			break;
3461 
3462 		run_pending = 1;
3463 
3464 		/* fall through */
3465 
3466 	case NETDEV_UP:
3467 	case NETDEV_CHANGE:
3468 		if (dev->flags & IFF_SLAVE)
3469 			break;
3470 
3471 		if (idev && idev->cnf.disable_ipv6)
3472 			break;
3473 
3474 		if (event == NETDEV_UP) {
3475 			/* restore routes for permanent addresses */
3476 			addrconf_permanent_addr(net, dev);
3477 
3478 			if (!addrconf_link_ready(dev)) {
3479 				/* device is not ready yet. */
3480 				pr_info("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3481 					dev->name);
3482 				break;
3483 			}
3484 
3485 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3486 				idev = ipv6_add_dev(dev);
3487 
3488 			if (!IS_ERR_OR_NULL(idev)) {
3489 				idev->if_flags |= IF_READY;
3490 				run_pending = 1;
3491 			}
3492 		} else if (event == NETDEV_CHANGE) {
3493 			if (!addrconf_link_ready(dev)) {
3494 				/* device is still not ready. */
3495 				rt6_sync_down_dev(dev, event);
3496 				break;
3497 			}
3498 
3499 			if (idev) {
3500 				if (idev->if_flags & IF_READY) {
3501 					/* device is already configured -
3502 					 * but resend MLD reports, we might
3503 					 * have roamed and need to update
3504 					 * multicast snooping switches
3505 					 */
3506 					ipv6_mc_up(idev);
3507 					rt6_sync_up(dev, RTNH_F_LINKDOWN);
3508 					break;
3509 				}
3510 				idev->if_flags |= IF_READY;
3511 			}
3512 
3513 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3514 				dev->name);
3515 
3516 			run_pending = 1;
3517 		}
3518 
3519 		switch (dev->type) {
3520 #if IS_ENABLED(CONFIG_IPV6_SIT)
3521 		case ARPHRD_SIT:
3522 			addrconf_sit_config(dev);
3523 			break;
3524 #endif
3525 #if IS_ENABLED(CONFIG_NET_IPGRE)
3526 		case ARPHRD_IPGRE:
3527 			addrconf_gre_config(dev);
3528 			break;
3529 #endif
3530 		case ARPHRD_LOOPBACK:
3531 			init_loopback(dev);
3532 			break;
3533 
3534 		default:
3535 			addrconf_dev_config(dev);
3536 			break;
3537 		}
3538 
3539 		if (!IS_ERR_OR_NULL(idev)) {
3540 			if (run_pending)
3541 				addrconf_dad_run(idev);
3542 
3543 			/* Device has an address by now */
3544 			rt6_sync_up(dev, RTNH_F_DEAD);
3545 
3546 			/*
3547 			 * If the MTU changed during the interface down,
3548 			 * when the interface up, the changed MTU must be
3549 			 * reflected in the idev as well as routers.
3550 			 */
3551 			if (idev->cnf.mtu6 != dev->mtu &&
3552 			    dev->mtu >= IPV6_MIN_MTU) {
3553 				rt6_mtu_change(dev, dev->mtu);
3554 				idev->cnf.mtu6 = dev->mtu;
3555 			}
3556 			idev->tstamp = jiffies;
3557 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3558 
3559 			/*
3560 			 * If the changed mtu during down is lower than
3561 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3562 			 */
3563 			if (dev->mtu < IPV6_MIN_MTU)
3564 				addrconf_ifdown(dev, dev != net->loopback_dev);
3565 		}
3566 		break;
3567 
3568 	case NETDEV_DOWN:
3569 	case NETDEV_UNREGISTER:
3570 		/*
3571 		 *	Remove all addresses from this interface.
3572 		 */
3573 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3574 		break;
3575 
3576 	case NETDEV_CHANGENAME:
3577 		if (idev) {
3578 			snmp6_unregister_dev(idev);
3579 			addrconf_sysctl_unregister(idev);
3580 			err = addrconf_sysctl_register(idev);
3581 			if (err)
3582 				return notifier_from_errno(err);
3583 			err = snmp6_register_dev(idev);
3584 			if (err) {
3585 				addrconf_sysctl_unregister(idev);
3586 				return notifier_from_errno(err);
3587 			}
3588 		}
3589 		break;
3590 
3591 	case NETDEV_PRE_TYPE_CHANGE:
3592 	case NETDEV_POST_TYPE_CHANGE:
3593 		if (idev)
3594 			addrconf_type_change(dev, event);
3595 		break;
3596 
3597 	case NETDEV_CHANGEUPPER:
3598 		info = ptr;
3599 
3600 		/* flush all routes if dev is linked to or unlinked from
3601 		 * an L3 master device (e.g., VRF)
3602 		 */
3603 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3604 			addrconf_ifdown(dev, 0);
3605 	}
3606 
3607 	return NOTIFY_OK;
3608 }
3609 
3610 /*
3611  *	addrconf module should be notified of a device going up
3612  */
3613 static struct notifier_block ipv6_dev_notf = {
3614 	.notifier_call = addrconf_notify,
3615 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3616 };
3617 
3618 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3619 {
3620 	struct inet6_dev *idev;
3621 	ASSERT_RTNL();
3622 
3623 	idev = __in6_dev_get(dev);
3624 
3625 	if (event == NETDEV_POST_TYPE_CHANGE)
3626 		ipv6_mc_remap(idev);
3627 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3628 		ipv6_mc_unmap(idev);
3629 }
3630 
3631 static bool addr_is_local(const struct in6_addr *addr)
3632 {
3633 	return ipv6_addr_type(addr) &
3634 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3635 }
3636 
3637 static int addrconf_ifdown(struct net_device *dev, int how)
3638 {
3639 	unsigned long event = how ? NETDEV_UNREGISTER : NETDEV_DOWN;
3640 	struct net *net = dev_net(dev);
3641 	struct inet6_dev *idev;
3642 	struct inet6_ifaddr *ifa, *tmp;
3643 	bool keep_addr = false;
3644 	int state, i;
3645 
3646 	ASSERT_RTNL();
3647 
3648 	rt6_disable_ip(dev, event);
3649 
3650 	idev = __in6_dev_get(dev);
3651 	if (!idev)
3652 		return -ENODEV;
3653 
3654 	/*
3655 	 * Step 1: remove reference to ipv6 device from parent device.
3656 	 *	   Do not dev_put!
3657 	 */
3658 	if (how) {
3659 		idev->dead = 1;
3660 
3661 		/* protected by rtnl_lock */
3662 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3663 
3664 		/* Step 1.5: remove snmp6 entry */
3665 		snmp6_unregister_dev(idev);
3666 
3667 	}
3668 
3669 	/* combine the user config with event to determine if permanent
3670 	 * addresses are to be removed from address hash table
3671 	 */
3672 	if (!how && !idev->cnf.disable_ipv6) {
3673 		/* aggregate the system setting and interface setting */
3674 		int _keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
3675 
3676 		if (!_keep_addr)
3677 			_keep_addr = idev->cnf.keep_addr_on_down;
3678 
3679 		keep_addr = (_keep_addr > 0);
3680 	}
3681 
3682 	/* Step 2: clear hash table */
3683 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3684 		struct hlist_head *h = &inet6_addr_lst[i];
3685 
3686 		spin_lock_bh(&addrconf_hash_lock);
3687 restart:
3688 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3689 			if (ifa->idev == idev) {
3690 				addrconf_del_dad_work(ifa);
3691 				/* combined flag + permanent flag decide if
3692 				 * address is retained on a down event
3693 				 */
3694 				if (!keep_addr ||
3695 				    !(ifa->flags & IFA_F_PERMANENT) ||
3696 				    addr_is_local(&ifa->addr)) {
3697 					hlist_del_init_rcu(&ifa->addr_lst);
3698 					goto restart;
3699 				}
3700 			}
3701 		}
3702 		spin_unlock_bh(&addrconf_hash_lock);
3703 	}
3704 
3705 	write_lock_bh(&idev->lock);
3706 
3707 	addrconf_del_rs_timer(idev);
3708 
3709 	/* Step 2: clear flags for stateless addrconf */
3710 	if (!how)
3711 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3712 
3713 	/* Step 3: clear tempaddr list */
3714 	while (!list_empty(&idev->tempaddr_list)) {
3715 		ifa = list_first_entry(&idev->tempaddr_list,
3716 				       struct inet6_ifaddr, tmp_list);
3717 		list_del(&ifa->tmp_list);
3718 		write_unlock_bh(&idev->lock);
3719 		spin_lock_bh(&ifa->lock);
3720 
3721 		if (ifa->ifpub) {
3722 			in6_ifa_put(ifa->ifpub);
3723 			ifa->ifpub = NULL;
3724 		}
3725 		spin_unlock_bh(&ifa->lock);
3726 		in6_ifa_put(ifa);
3727 		write_lock_bh(&idev->lock);
3728 	}
3729 
3730 	list_for_each_entry_safe(ifa, tmp, &idev->addr_list, if_list) {
3731 		struct fib6_info *rt = NULL;
3732 		bool keep;
3733 
3734 		addrconf_del_dad_work(ifa);
3735 
3736 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3737 			!addr_is_local(&ifa->addr);
3738 
3739 		write_unlock_bh(&idev->lock);
3740 		spin_lock_bh(&ifa->lock);
3741 
3742 		if (keep) {
3743 			/* set state to skip the notifier below */
3744 			state = INET6_IFADDR_STATE_DEAD;
3745 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3746 			if (!(ifa->flags & IFA_F_NODAD))
3747 				ifa->flags |= IFA_F_TENTATIVE;
3748 
3749 			rt = ifa->rt;
3750 			ifa->rt = NULL;
3751 		} else {
3752 			state = ifa->state;
3753 			ifa->state = INET6_IFADDR_STATE_DEAD;
3754 		}
3755 
3756 		spin_unlock_bh(&ifa->lock);
3757 
3758 		if (rt)
3759 			ip6_del_rt(net, rt);
3760 
3761 		if (state != INET6_IFADDR_STATE_DEAD) {
3762 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3763 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3764 		} else {
3765 			if (idev->cnf.forwarding)
3766 				addrconf_leave_anycast(ifa);
3767 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3768 		}
3769 
3770 		write_lock_bh(&idev->lock);
3771 		if (!keep) {
3772 			list_del_rcu(&ifa->if_list);
3773 			in6_ifa_put(ifa);
3774 		}
3775 	}
3776 
3777 	write_unlock_bh(&idev->lock);
3778 
3779 	/* Step 5: Discard anycast and multicast list */
3780 	if (how) {
3781 		ipv6_ac_destroy_dev(idev);
3782 		ipv6_mc_destroy_dev(idev);
3783 	} else {
3784 		ipv6_mc_down(idev);
3785 	}
3786 
3787 	idev->tstamp = jiffies;
3788 
3789 	/* Last: Shot the device (if unregistered) */
3790 	if (how) {
3791 		addrconf_sysctl_unregister(idev);
3792 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3793 		neigh_ifdown(&nd_tbl, dev);
3794 		in6_dev_put(idev);
3795 	}
3796 	return 0;
3797 }
3798 
3799 static void addrconf_rs_timer(struct timer_list *t)
3800 {
3801 	struct inet6_dev *idev = from_timer(idev, t, rs_timer);
3802 	struct net_device *dev = idev->dev;
3803 	struct in6_addr lladdr;
3804 
3805 	write_lock(&idev->lock);
3806 	if (idev->dead || !(idev->if_flags & IF_READY))
3807 		goto out;
3808 
3809 	if (!ipv6_accept_ra(idev))
3810 		goto out;
3811 
3812 	/* Announcement received after solicitation was sent */
3813 	if (idev->if_flags & IF_RA_RCVD)
3814 		goto out;
3815 
3816 	if (idev->rs_probes++ < idev->cnf.rtr_solicits || idev->cnf.rtr_solicits < 0) {
3817 		write_unlock(&idev->lock);
3818 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3819 			ndisc_send_rs(dev, &lladdr,
3820 				      &in6addr_linklocal_allrouters);
3821 		else
3822 			goto put;
3823 
3824 		write_lock(&idev->lock);
3825 		idev->rs_interval = rfc3315_s14_backoff_update(
3826 			idev->rs_interval, idev->cnf.rtr_solicit_max_interval);
3827 		/* The wait after the last probe can be shorter */
3828 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3829 					     idev->cnf.rtr_solicits) ?
3830 				      idev->cnf.rtr_solicit_delay :
3831 				      idev->rs_interval);
3832 	} else {
3833 		/*
3834 		 * Note: we do not support deprecated "all on-link"
3835 		 * assumption any longer.
3836 		 */
3837 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3838 	}
3839 
3840 out:
3841 	write_unlock(&idev->lock);
3842 put:
3843 	in6_dev_put(idev);
3844 }
3845 
3846 /*
3847  *	Duplicate Address Detection
3848  */
3849 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3850 {
3851 	unsigned long rand_num;
3852 	struct inet6_dev *idev = ifp->idev;
3853 	u64 nonce;
3854 
3855 	if (ifp->flags & IFA_F_OPTIMISTIC)
3856 		rand_num = 0;
3857 	else
3858 		rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3859 
3860 	nonce = 0;
3861 	if (idev->cnf.enhanced_dad ||
3862 	    dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad) {
3863 		do
3864 			get_random_bytes(&nonce, 6);
3865 		while (nonce == 0);
3866 	}
3867 	ifp->dad_nonce = nonce;
3868 	ifp->dad_probes = idev->cnf.dad_transmits;
3869 	addrconf_mod_dad_work(ifp, rand_num);
3870 }
3871 
3872 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3873 {
3874 	struct inet6_dev *idev = ifp->idev;
3875 	struct net_device *dev = idev->dev;
3876 	bool bump_id, notify = false;
3877 	struct net *net;
3878 
3879 	addrconf_join_solict(dev, &ifp->addr);
3880 
3881 	prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3882 
3883 	read_lock_bh(&idev->lock);
3884 	spin_lock(&ifp->lock);
3885 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3886 		goto out;
3887 
3888 	net = dev_net(dev);
3889 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3890 	    (net->ipv6.devconf_all->accept_dad < 1 &&
3891 	     idev->cnf.accept_dad < 1) ||
3892 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3893 	    ifp->flags & IFA_F_NODAD) {
3894 		bool send_na = false;
3895 
3896 		if (ifp->flags & IFA_F_TENTATIVE &&
3897 		    !(ifp->flags & IFA_F_OPTIMISTIC))
3898 			send_na = true;
3899 		bump_id = ifp->flags & IFA_F_TENTATIVE;
3900 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3901 		spin_unlock(&ifp->lock);
3902 		read_unlock_bh(&idev->lock);
3903 
3904 		addrconf_dad_completed(ifp, bump_id, send_na);
3905 		return;
3906 	}
3907 
3908 	if (!(idev->if_flags & IF_READY)) {
3909 		spin_unlock(&ifp->lock);
3910 		read_unlock_bh(&idev->lock);
3911 		/*
3912 		 * If the device is not ready:
3913 		 * - keep it tentative if it is a permanent address.
3914 		 * - otherwise, kill it.
3915 		 */
3916 		in6_ifa_hold(ifp);
3917 		addrconf_dad_stop(ifp, 0);
3918 		return;
3919 	}
3920 
3921 	/*
3922 	 * Optimistic nodes can start receiving
3923 	 * Frames right away
3924 	 */
3925 	if (ifp->flags & IFA_F_OPTIMISTIC) {
3926 		ip6_ins_rt(net, ifp->rt);
3927 		if (ipv6_use_optimistic_addr(net, idev)) {
3928 			/* Because optimistic nodes can use this address,
3929 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
3930 			 */
3931 			notify = true;
3932 		}
3933 	}
3934 
3935 	addrconf_dad_kick(ifp);
3936 out:
3937 	spin_unlock(&ifp->lock);
3938 	read_unlock_bh(&idev->lock);
3939 	if (notify)
3940 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3941 }
3942 
3943 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
3944 {
3945 	bool begin_dad = false;
3946 
3947 	spin_lock_bh(&ifp->lock);
3948 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
3949 		ifp->state = INET6_IFADDR_STATE_PREDAD;
3950 		begin_dad = true;
3951 	}
3952 	spin_unlock_bh(&ifp->lock);
3953 
3954 	if (begin_dad)
3955 		addrconf_mod_dad_work(ifp, 0);
3956 }
3957 
3958 static void addrconf_dad_work(struct work_struct *w)
3959 {
3960 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
3961 						struct inet6_ifaddr,
3962 						dad_work);
3963 	struct inet6_dev *idev = ifp->idev;
3964 	bool bump_id, disable_ipv6 = false;
3965 	struct in6_addr mcaddr;
3966 
3967 	enum {
3968 		DAD_PROCESS,
3969 		DAD_BEGIN,
3970 		DAD_ABORT,
3971 	} action = DAD_PROCESS;
3972 
3973 	rtnl_lock();
3974 
3975 	spin_lock_bh(&ifp->lock);
3976 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
3977 		action = DAD_BEGIN;
3978 		ifp->state = INET6_IFADDR_STATE_DAD;
3979 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
3980 		action = DAD_ABORT;
3981 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
3982 
3983 		if ((dev_net(idev->dev)->ipv6.devconf_all->accept_dad > 1 ||
3984 		     idev->cnf.accept_dad > 1) &&
3985 		    !idev->cnf.disable_ipv6 &&
3986 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
3987 			struct in6_addr addr;
3988 
3989 			addr.s6_addr32[0] = htonl(0xfe800000);
3990 			addr.s6_addr32[1] = 0;
3991 
3992 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
3993 			    ipv6_addr_equal(&ifp->addr, &addr)) {
3994 				/* DAD failed for link-local based on MAC */
3995 				idev->cnf.disable_ipv6 = 1;
3996 
3997 				pr_info("%s: IPv6 being disabled!\n",
3998 					ifp->idev->dev->name);
3999 				disable_ipv6 = true;
4000 			}
4001 		}
4002 	}
4003 	spin_unlock_bh(&ifp->lock);
4004 
4005 	if (action == DAD_BEGIN) {
4006 		addrconf_dad_begin(ifp);
4007 		goto out;
4008 	} else if (action == DAD_ABORT) {
4009 		in6_ifa_hold(ifp);
4010 		addrconf_dad_stop(ifp, 1);
4011 		if (disable_ipv6)
4012 			addrconf_ifdown(idev->dev, 0);
4013 		goto out;
4014 	}
4015 
4016 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
4017 		goto out;
4018 
4019 	write_lock_bh(&idev->lock);
4020 	if (idev->dead || !(idev->if_flags & IF_READY)) {
4021 		write_unlock_bh(&idev->lock);
4022 		goto out;
4023 	}
4024 
4025 	spin_lock(&ifp->lock);
4026 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
4027 		spin_unlock(&ifp->lock);
4028 		write_unlock_bh(&idev->lock);
4029 		goto out;
4030 	}
4031 
4032 	if (ifp->dad_probes == 0) {
4033 		bool send_na = false;
4034 
4035 		/*
4036 		 * DAD was successful
4037 		 */
4038 
4039 		if (ifp->flags & IFA_F_TENTATIVE &&
4040 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4041 			send_na = true;
4042 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4043 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4044 		spin_unlock(&ifp->lock);
4045 		write_unlock_bh(&idev->lock);
4046 
4047 		addrconf_dad_completed(ifp, bump_id, send_na);
4048 
4049 		goto out;
4050 	}
4051 
4052 	ifp->dad_probes--;
4053 	addrconf_mod_dad_work(ifp,
4054 			      NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME));
4055 	spin_unlock(&ifp->lock);
4056 	write_unlock_bh(&idev->lock);
4057 
4058 	/* send a neighbour solicitation for our addr */
4059 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4060 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4061 		      ifp->dad_nonce);
4062 out:
4063 	in6_ifa_put(ifp);
4064 	rtnl_unlock();
4065 }
4066 
4067 /* ifp->idev must be at least read locked */
4068 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4069 {
4070 	struct inet6_ifaddr *ifpiter;
4071 	struct inet6_dev *idev = ifp->idev;
4072 
4073 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4074 		if (ifpiter->scope > IFA_LINK)
4075 			break;
4076 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4077 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4078 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4079 		    IFA_F_PERMANENT)
4080 			return false;
4081 	}
4082 	return true;
4083 }
4084 
4085 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
4086 				   bool send_na)
4087 {
4088 	struct net_device *dev = ifp->idev->dev;
4089 	struct in6_addr lladdr;
4090 	bool send_rs, send_mld;
4091 
4092 	addrconf_del_dad_work(ifp);
4093 
4094 	/*
4095 	 *	Configure the address for reception. Now it is valid.
4096 	 */
4097 
4098 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4099 
4100 	/* If added prefix is link local and we are prepared to process
4101 	   router advertisements, start sending router solicitations.
4102 	 */
4103 
4104 	read_lock_bh(&ifp->idev->lock);
4105 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4106 	send_rs = send_mld &&
4107 		  ipv6_accept_ra(ifp->idev) &&
4108 		  ifp->idev->cnf.rtr_solicits != 0 &&
4109 		  (dev->flags&IFF_LOOPBACK) == 0;
4110 	read_unlock_bh(&ifp->idev->lock);
4111 
4112 	/* While dad is in progress mld report's source address is in6_addrany.
4113 	 * Resend with proper ll now.
4114 	 */
4115 	if (send_mld)
4116 		ipv6_mc_dad_complete(ifp->idev);
4117 
4118 	/* send unsolicited NA if enabled */
4119 	if (send_na &&
4120 	    (ifp->idev->cnf.ndisc_notify ||
4121 	     dev_net(dev)->ipv6.devconf_all->ndisc_notify)) {
4122 		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifp->addr,
4123 			      /*router=*/ !!ifp->idev->cnf.forwarding,
4124 			      /*solicited=*/ false, /*override=*/ true,
4125 			      /*inc_opt=*/ true);
4126 	}
4127 
4128 	if (send_rs) {
4129 		/*
4130 		 *	If a host as already performed a random delay
4131 		 *	[...] as part of DAD [...] there is no need
4132 		 *	to delay again before sending the first RS
4133 		 */
4134 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4135 			return;
4136 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4137 
4138 		write_lock_bh(&ifp->idev->lock);
4139 		spin_lock(&ifp->lock);
4140 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4141 			ifp->idev->cnf.rtr_solicit_interval);
4142 		ifp->idev->rs_probes = 1;
4143 		ifp->idev->if_flags |= IF_RS_SENT;
4144 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4145 		spin_unlock(&ifp->lock);
4146 		write_unlock_bh(&ifp->idev->lock);
4147 	}
4148 
4149 	if (bump_id)
4150 		rt_genid_bump_ipv6(dev_net(dev));
4151 
4152 	/* Make sure that a new temporary address will be created
4153 	 * before this temporary address becomes deprecated.
4154 	 */
4155 	if (ifp->flags & IFA_F_TEMPORARY)
4156 		addrconf_verify_rtnl();
4157 }
4158 
4159 static void addrconf_dad_run(struct inet6_dev *idev)
4160 {
4161 	struct inet6_ifaddr *ifp;
4162 
4163 	read_lock_bh(&idev->lock);
4164 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4165 		spin_lock(&ifp->lock);
4166 		if (ifp->flags & IFA_F_TENTATIVE &&
4167 		    ifp->state == INET6_IFADDR_STATE_DAD)
4168 			addrconf_dad_kick(ifp);
4169 		spin_unlock(&ifp->lock);
4170 	}
4171 	read_unlock_bh(&idev->lock);
4172 }
4173 
4174 #ifdef CONFIG_PROC_FS
4175 struct if6_iter_state {
4176 	struct seq_net_private p;
4177 	int bucket;
4178 	int offset;
4179 };
4180 
4181 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4182 {
4183 	struct if6_iter_state *state = seq->private;
4184 	struct net *net = seq_file_net(seq);
4185 	struct inet6_ifaddr *ifa = NULL;
4186 	int p = 0;
4187 
4188 	/* initial bucket if pos is 0 */
4189 	if (pos == 0) {
4190 		state->bucket = 0;
4191 		state->offset = 0;
4192 	}
4193 
4194 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4195 		hlist_for_each_entry_rcu(ifa, &inet6_addr_lst[state->bucket],
4196 					 addr_lst) {
4197 			if (!net_eq(dev_net(ifa->idev->dev), net))
4198 				continue;
4199 			/* sync with offset */
4200 			if (p < state->offset) {
4201 				p++;
4202 				continue;
4203 			}
4204 			state->offset++;
4205 			return ifa;
4206 		}
4207 
4208 		/* prepare for next bucket */
4209 		state->offset = 0;
4210 		p = 0;
4211 	}
4212 	return NULL;
4213 }
4214 
4215 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4216 					 struct inet6_ifaddr *ifa)
4217 {
4218 	struct if6_iter_state *state = seq->private;
4219 	struct net *net = seq_file_net(seq);
4220 
4221 	hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4222 		if (!net_eq(dev_net(ifa->idev->dev), net))
4223 			continue;
4224 		state->offset++;
4225 		return ifa;
4226 	}
4227 
4228 	while (++state->bucket < IN6_ADDR_HSIZE) {
4229 		state->offset = 0;
4230 		hlist_for_each_entry_rcu(ifa,
4231 				     &inet6_addr_lst[state->bucket], addr_lst) {
4232 			if (!net_eq(dev_net(ifa->idev->dev), net))
4233 				continue;
4234 			state->offset++;
4235 			return ifa;
4236 		}
4237 	}
4238 
4239 	return NULL;
4240 }
4241 
4242 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4243 	__acquires(rcu)
4244 {
4245 	rcu_read_lock();
4246 	return if6_get_first(seq, *pos);
4247 }
4248 
4249 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4250 {
4251 	struct inet6_ifaddr *ifa;
4252 
4253 	ifa = if6_get_next(seq, v);
4254 	++*pos;
4255 	return ifa;
4256 }
4257 
4258 static void if6_seq_stop(struct seq_file *seq, void *v)
4259 	__releases(rcu)
4260 {
4261 	rcu_read_unlock();
4262 }
4263 
4264 static int if6_seq_show(struct seq_file *seq, void *v)
4265 {
4266 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4267 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4268 		   &ifp->addr,
4269 		   ifp->idev->dev->ifindex,
4270 		   ifp->prefix_len,
4271 		   ifp->scope,
4272 		   (u8) ifp->flags,
4273 		   ifp->idev->dev->name);
4274 	return 0;
4275 }
4276 
4277 static const struct seq_operations if6_seq_ops = {
4278 	.start	= if6_seq_start,
4279 	.next	= if6_seq_next,
4280 	.show	= if6_seq_show,
4281 	.stop	= if6_seq_stop,
4282 };
4283 
4284 static int __net_init if6_proc_net_init(struct net *net)
4285 {
4286 	if (!proc_create_net("if_inet6", 0444, net->proc_net, &if6_seq_ops,
4287 			sizeof(struct if6_iter_state)))
4288 		return -ENOMEM;
4289 	return 0;
4290 }
4291 
4292 static void __net_exit if6_proc_net_exit(struct net *net)
4293 {
4294 	remove_proc_entry("if_inet6", net->proc_net);
4295 }
4296 
4297 static struct pernet_operations if6_proc_net_ops = {
4298 	.init = if6_proc_net_init,
4299 	.exit = if6_proc_net_exit,
4300 };
4301 
4302 int __init if6_proc_init(void)
4303 {
4304 	return register_pernet_subsys(&if6_proc_net_ops);
4305 }
4306 
4307 void if6_proc_exit(void)
4308 {
4309 	unregister_pernet_subsys(&if6_proc_net_ops);
4310 }
4311 #endif	/* CONFIG_PROC_FS */
4312 
4313 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4314 /* Check if address is a home address configured on any interface. */
4315 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4316 {
4317 	unsigned int hash = inet6_addr_hash(net, addr);
4318 	struct inet6_ifaddr *ifp = NULL;
4319 	int ret = 0;
4320 
4321 	rcu_read_lock();
4322 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
4323 		if (!net_eq(dev_net(ifp->idev->dev), net))
4324 			continue;
4325 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4326 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4327 			ret = 1;
4328 			break;
4329 		}
4330 	}
4331 	rcu_read_unlock();
4332 	return ret;
4333 }
4334 #endif
4335 
4336 /*
4337  *	Periodic address status verification
4338  */
4339 
4340 static void addrconf_verify_rtnl(void)
4341 {
4342 	unsigned long now, next, next_sec, next_sched;
4343 	struct inet6_ifaddr *ifp;
4344 	int i;
4345 
4346 	ASSERT_RTNL();
4347 
4348 	rcu_read_lock_bh();
4349 	now = jiffies;
4350 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4351 
4352 	cancel_delayed_work(&addr_chk_work);
4353 
4354 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4355 restart:
4356 		hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
4357 			unsigned long age;
4358 
4359 			/* When setting preferred_lft to a value not zero or
4360 			 * infinity, while valid_lft is infinity
4361 			 * IFA_F_PERMANENT has a non-infinity life time.
4362 			 */
4363 			if ((ifp->flags & IFA_F_PERMANENT) &&
4364 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4365 				continue;
4366 
4367 			spin_lock(&ifp->lock);
4368 			/* We try to batch several events at once. */
4369 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4370 
4371 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4372 			    age >= ifp->valid_lft) {
4373 				spin_unlock(&ifp->lock);
4374 				in6_ifa_hold(ifp);
4375 				ipv6_del_addr(ifp);
4376 				goto restart;
4377 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4378 				spin_unlock(&ifp->lock);
4379 				continue;
4380 			} else if (age >= ifp->prefered_lft) {
4381 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4382 				int deprecate = 0;
4383 
4384 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4385 					deprecate = 1;
4386 					ifp->flags |= IFA_F_DEPRECATED;
4387 				}
4388 
4389 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4390 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4391 					next = ifp->tstamp + ifp->valid_lft * HZ;
4392 
4393 				spin_unlock(&ifp->lock);
4394 
4395 				if (deprecate) {
4396 					in6_ifa_hold(ifp);
4397 
4398 					ipv6_ifa_notify(0, ifp);
4399 					in6_ifa_put(ifp);
4400 					goto restart;
4401 				}
4402 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
4403 				   !(ifp->flags&IFA_F_TENTATIVE)) {
4404 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
4405 					ifp->idev->cnf.dad_transmits *
4406 					NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME) / HZ;
4407 
4408 				if (age >= ifp->prefered_lft - regen_advance) {
4409 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4410 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4411 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4412 					if (!ifp->regen_count && ifpub) {
4413 						ifp->regen_count++;
4414 						in6_ifa_hold(ifp);
4415 						in6_ifa_hold(ifpub);
4416 						spin_unlock(&ifp->lock);
4417 
4418 						spin_lock(&ifpub->lock);
4419 						ifpub->regen_count = 0;
4420 						spin_unlock(&ifpub->lock);
4421 						rcu_read_unlock_bh();
4422 						ipv6_create_tempaddr(ifpub, ifp, true);
4423 						in6_ifa_put(ifpub);
4424 						in6_ifa_put(ifp);
4425 						rcu_read_lock_bh();
4426 						goto restart;
4427 					}
4428 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4429 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4430 				spin_unlock(&ifp->lock);
4431 			} else {
4432 				/* ifp->prefered_lft <= ifp->valid_lft */
4433 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4434 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4435 				spin_unlock(&ifp->lock);
4436 			}
4437 		}
4438 	}
4439 
4440 	next_sec = round_jiffies_up(next);
4441 	next_sched = next;
4442 
4443 	/* If rounded timeout is accurate enough, accept it. */
4444 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4445 		next_sched = next_sec;
4446 
4447 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4448 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4449 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4450 
4451 	pr_debug("now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4452 		 now, next, next_sec, next_sched);
4453 	mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
4454 	rcu_read_unlock_bh();
4455 }
4456 
4457 static void addrconf_verify_work(struct work_struct *w)
4458 {
4459 	rtnl_lock();
4460 	addrconf_verify_rtnl();
4461 	rtnl_unlock();
4462 }
4463 
4464 static void addrconf_verify(void)
4465 {
4466 	mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
4467 }
4468 
4469 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4470 				     struct in6_addr **peer_pfx)
4471 {
4472 	struct in6_addr *pfx = NULL;
4473 
4474 	*peer_pfx = NULL;
4475 
4476 	if (addr)
4477 		pfx = nla_data(addr);
4478 
4479 	if (local) {
4480 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4481 			*peer_pfx = pfx;
4482 		pfx = nla_data(local);
4483 	}
4484 
4485 	return pfx;
4486 }
4487 
4488 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4489 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4490 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4491 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4492 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4493 	[IFA_RT_PRIORITY]	= { .len = sizeof(u32) },
4494 	[IFA_TARGET_NETNSID]	= { .type = NLA_S32 },
4495 };
4496 
4497 static int
4498 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4499 		  struct netlink_ext_ack *extack)
4500 {
4501 	struct net *net = sock_net(skb->sk);
4502 	struct ifaddrmsg *ifm;
4503 	struct nlattr *tb[IFA_MAX+1];
4504 	struct in6_addr *pfx, *peer_pfx;
4505 	u32 ifa_flags;
4506 	int err;
4507 
4508 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4509 			  extack);
4510 	if (err < 0)
4511 		return err;
4512 
4513 	ifm = nlmsg_data(nlh);
4514 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4515 	if (!pfx)
4516 		return -EINVAL;
4517 
4518 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4519 
4520 	/* We ignore other flags so far. */
4521 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4522 
4523 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4524 			      ifm->ifa_prefixlen);
4525 }
4526 
4527 static int modify_prefix_route(struct inet6_ifaddr *ifp,
4528 			       unsigned long expires, u32 flags)
4529 {
4530 	struct fib6_info *f6i;
4531 	u32 prio;
4532 
4533 	f6i = addrconf_get_prefix_route(&ifp->addr,
4534 					ifp->prefix_len,
4535 					ifp->idev->dev,
4536 					0, RTF_GATEWAY | RTF_DEFAULT);
4537 	if (!f6i)
4538 		return -ENOENT;
4539 
4540 	prio = ifp->rt_priority ? : IP6_RT_PRIO_ADDRCONF;
4541 	if (f6i->fib6_metric != prio) {
4542 		/* delete old one */
4543 		ip6_del_rt(dev_net(ifp->idev->dev), f6i);
4544 
4545 		/* add new one */
4546 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4547 				      ifp->rt_priority, ifp->idev->dev,
4548 				      expires, flags, GFP_KERNEL);
4549 	} else {
4550 		if (!expires)
4551 			fib6_clean_expires(f6i);
4552 		else
4553 			fib6_set_expires(f6i, expires);
4554 
4555 		fib6_info_release(f6i);
4556 	}
4557 
4558 	return 0;
4559 }
4560 
4561 static int inet6_addr_modify(struct inet6_ifaddr *ifp, struct ifa6_config *cfg)
4562 {
4563 	u32 flags;
4564 	clock_t expires;
4565 	unsigned long timeout;
4566 	bool was_managetempaddr;
4567 	bool had_prefixroute;
4568 
4569 	ASSERT_RTNL();
4570 
4571 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
4572 		return -EINVAL;
4573 
4574 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR &&
4575 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4576 		return -EINVAL;
4577 
4578 	if (!(ifp->flags & IFA_F_TENTATIVE) || ifp->flags & IFA_F_DADFAILED)
4579 		cfg->ifa_flags &= ~IFA_F_OPTIMISTIC;
4580 
4581 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
4582 	if (addrconf_finite_timeout(timeout)) {
4583 		expires = jiffies_to_clock_t(timeout * HZ);
4584 		cfg->valid_lft = timeout;
4585 		flags = RTF_EXPIRES;
4586 	} else {
4587 		expires = 0;
4588 		flags = 0;
4589 		cfg->ifa_flags |= IFA_F_PERMANENT;
4590 	}
4591 
4592 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
4593 	if (addrconf_finite_timeout(timeout)) {
4594 		if (timeout == 0)
4595 			cfg->ifa_flags |= IFA_F_DEPRECATED;
4596 		cfg->preferred_lft = timeout;
4597 	}
4598 
4599 	spin_lock_bh(&ifp->lock);
4600 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4601 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4602 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4603 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4604 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4605 			IFA_F_NOPREFIXROUTE);
4606 	ifp->flags |= cfg->ifa_flags;
4607 	ifp->tstamp = jiffies;
4608 	ifp->valid_lft = cfg->valid_lft;
4609 	ifp->prefered_lft = cfg->preferred_lft;
4610 
4611 	if (cfg->rt_priority && cfg->rt_priority != ifp->rt_priority)
4612 		ifp->rt_priority = cfg->rt_priority;
4613 
4614 	spin_unlock_bh(&ifp->lock);
4615 	if (!(ifp->flags&IFA_F_TENTATIVE))
4616 		ipv6_ifa_notify(0, ifp);
4617 
4618 	if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
4619 		int rc = -ENOENT;
4620 
4621 		if (had_prefixroute)
4622 			rc = modify_prefix_route(ifp, expires, flags);
4623 
4624 		/* prefix route could have been deleted; if so restore it */
4625 		if (rc == -ENOENT) {
4626 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4627 					      ifp->rt_priority, ifp->idev->dev,
4628 					      expires, flags, GFP_KERNEL);
4629 		}
4630 	} else if (had_prefixroute) {
4631 		enum cleanup_prefix_rt_t action;
4632 		unsigned long rt_expires;
4633 
4634 		write_lock_bh(&ifp->idev->lock);
4635 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4636 		write_unlock_bh(&ifp->idev->lock);
4637 
4638 		if (action != CLEANUP_PREFIX_RT_NOP) {
4639 			cleanup_prefix_route(ifp, rt_expires,
4640 				action == CLEANUP_PREFIX_RT_DEL);
4641 		}
4642 	}
4643 
4644 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4645 		if (was_managetempaddr &&
4646 		    !(ifp->flags & IFA_F_MANAGETEMPADDR)) {
4647 			cfg->valid_lft = 0;
4648 			cfg->preferred_lft = 0;
4649 		}
4650 		manage_tempaddrs(ifp->idev, ifp, cfg->valid_lft,
4651 				 cfg->preferred_lft, !was_managetempaddr,
4652 				 jiffies);
4653 	}
4654 
4655 	addrconf_verify_rtnl();
4656 
4657 	return 0;
4658 }
4659 
4660 static int
4661 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4662 		  struct netlink_ext_ack *extack)
4663 {
4664 	struct net *net = sock_net(skb->sk);
4665 	struct ifaddrmsg *ifm;
4666 	struct nlattr *tb[IFA_MAX+1];
4667 	struct in6_addr *peer_pfx;
4668 	struct inet6_ifaddr *ifa;
4669 	struct net_device *dev;
4670 	struct inet6_dev *idev;
4671 	struct ifa6_config cfg;
4672 	int err;
4673 
4674 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4675 			  extack);
4676 	if (err < 0)
4677 		return err;
4678 
4679 	memset(&cfg, 0, sizeof(cfg));
4680 
4681 	ifm = nlmsg_data(nlh);
4682 	cfg.pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4683 	if (!cfg.pfx)
4684 		return -EINVAL;
4685 
4686 	cfg.peer_pfx = peer_pfx;
4687 	cfg.plen = ifm->ifa_prefixlen;
4688 	if (tb[IFA_RT_PRIORITY])
4689 		cfg.rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
4690 
4691 	cfg.valid_lft = INFINITY_LIFE_TIME;
4692 	cfg.preferred_lft = INFINITY_LIFE_TIME;
4693 
4694 	if (tb[IFA_CACHEINFO]) {
4695 		struct ifa_cacheinfo *ci;
4696 
4697 		ci = nla_data(tb[IFA_CACHEINFO]);
4698 		cfg.valid_lft = ci->ifa_valid;
4699 		cfg.preferred_lft = ci->ifa_prefered;
4700 	}
4701 
4702 	dev =  __dev_get_by_index(net, ifm->ifa_index);
4703 	if (!dev)
4704 		return -ENODEV;
4705 
4706 	if (tb[IFA_FLAGS])
4707 		cfg.ifa_flags = nla_get_u32(tb[IFA_FLAGS]);
4708 	else
4709 		cfg.ifa_flags = ifm->ifa_flags;
4710 
4711 	/* We ignore other flags so far. */
4712 	cfg.ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS |
4713 			 IFA_F_MANAGETEMPADDR | IFA_F_NOPREFIXROUTE |
4714 			 IFA_F_MCAUTOJOIN | IFA_F_OPTIMISTIC;
4715 
4716 	idev = ipv6_find_idev(dev);
4717 	if (IS_ERR(idev))
4718 		return PTR_ERR(idev);
4719 
4720 	if (!ipv6_allow_optimistic_dad(net, idev))
4721 		cfg.ifa_flags &= ~IFA_F_OPTIMISTIC;
4722 
4723 	if (cfg.ifa_flags & IFA_F_NODAD &&
4724 	    cfg.ifa_flags & IFA_F_OPTIMISTIC) {
4725 		NL_SET_ERR_MSG(extack, "IFA_F_NODAD and IFA_F_OPTIMISTIC are mutually exclusive");
4726 		return -EINVAL;
4727 	}
4728 
4729 	ifa = ipv6_get_ifaddr(net, cfg.pfx, dev, 1);
4730 	if (!ifa) {
4731 		/*
4732 		 * It would be best to check for !NLM_F_CREATE here but
4733 		 * userspace already relies on not having to provide this.
4734 		 */
4735 		return inet6_addr_add(net, ifm->ifa_index, &cfg, extack);
4736 	}
4737 
4738 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
4739 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
4740 		err = -EEXIST;
4741 	else
4742 		err = inet6_addr_modify(ifa, &cfg);
4743 
4744 	in6_ifa_put(ifa);
4745 
4746 	return err;
4747 }
4748 
4749 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
4750 			  u8 scope, int ifindex)
4751 {
4752 	struct ifaddrmsg *ifm;
4753 
4754 	ifm = nlmsg_data(nlh);
4755 	ifm->ifa_family = AF_INET6;
4756 	ifm->ifa_prefixlen = prefixlen;
4757 	ifm->ifa_flags = flags;
4758 	ifm->ifa_scope = scope;
4759 	ifm->ifa_index = ifindex;
4760 }
4761 
4762 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
4763 			 unsigned long tstamp, u32 preferred, u32 valid)
4764 {
4765 	struct ifa_cacheinfo ci;
4766 
4767 	ci.cstamp = cstamp_delta(cstamp);
4768 	ci.tstamp = cstamp_delta(tstamp);
4769 	ci.ifa_prefered = preferred;
4770 	ci.ifa_valid = valid;
4771 
4772 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
4773 }
4774 
4775 static inline int rt_scope(int ifa_scope)
4776 {
4777 	if (ifa_scope & IFA_HOST)
4778 		return RT_SCOPE_HOST;
4779 	else if (ifa_scope & IFA_LINK)
4780 		return RT_SCOPE_LINK;
4781 	else if (ifa_scope & IFA_SITE)
4782 		return RT_SCOPE_SITE;
4783 	else
4784 		return RT_SCOPE_UNIVERSE;
4785 }
4786 
4787 static inline int inet6_ifaddr_msgsize(void)
4788 {
4789 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
4790 	       + nla_total_size(16) /* IFA_LOCAL */
4791 	       + nla_total_size(16) /* IFA_ADDRESS */
4792 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
4793 	       + nla_total_size(4)  /* IFA_FLAGS */
4794 	       + nla_total_size(4)  /* IFA_RT_PRIORITY */;
4795 }
4796 
4797 struct inet6_fill_args {
4798 	u32 portid;
4799 	u32 seq;
4800 	int event;
4801 	unsigned int flags;
4802 	int netnsid;
4803 };
4804 
4805 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
4806 			     struct inet6_fill_args *args)
4807 {
4808 	struct nlmsghdr  *nlh;
4809 	u32 preferred, valid;
4810 
4811 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
4812 			sizeof(struct ifaddrmsg), args->flags);
4813 	if (!nlh)
4814 		return -EMSGSIZE;
4815 
4816 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
4817 		      ifa->idev->dev->ifindex);
4818 
4819 	if (args->netnsid >= 0 &&
4820 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
4821 		goto error;
4822 
4823 	if (!((ifa->flags&IFA_F_PERMANENT) &&
4824 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
4825 		preferred = ifa->prefered_lft;
4826 		valid = ifa->valid_lft;
4827 		if (preferred != INFINITY_LIFE_TIME) {
4828 			long tval = (jiffies - ifa->tstamp)/HZ;
4829 			if (preferred > tval)
4830 				preferred -= tval;
4831 			else
4832 				preferred = 0;
4833 			if (valid != INFINITY_LIFE_TIME) {
4834 				if (valid > tval)
4835 					valid -= tval;
4836 				else
4837 					valid = 0;
4838 			}
4839 		}
4840 	} else {
4841 		preferred = INFINITY_LIFE_TIME;
4842 		valid = INFINITY_LIFE_TIME;
4843 	}
4844 
4845 	if (!ipv6_addr_any(&ifa->peer_addr)) {
4846 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
4847 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
4848 			goto error;
4849 	} else
4850 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
4851 			goto error;
4852 
4853 	if (ifa->rt_priority &&
4854 	    nla_put_u32(skb, IFA_RT_PRIORITY, ifa->rt_priority))
4855 		goto error;
4856 
4857 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
4858 		goto error;
4859 
4860 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
4861 		goto error;
4862 
4863 	nlmsg_end(skb, nlh);
4864 	return 0;
4865 
4866 error:
4867 	nlmsg_cancel(skb, nlh);
4868 	return -EMSGSIZE;
4869 }
4870 
4871 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
4872 			       struct inet6_fill_args *args)
4873 {
4874 	struct nlmsghdr  *nlh;
4875 	u8 scope = RT_SCOPE_UNIVERSE;
4876 	int ifindex = ifmca->idev->dev->ifindex;
4877 
4878 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
4879 		scope = RT_SCOPE_SITE;
4880 
4881 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
4882 			sizeof(struct ifaddrmsg), args->flags);
4883 	if (!nlh)
4884 		return -EMSGSIZE;
4885 
4886 	if (args->netnsid >= 0 &&
4887 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
4888 		return -EMSGSIZE;
4889 
4890 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4891 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
4892 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
4893 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4894 		nlmsg_cancel(skb, nlh);
4895 		return -EMSGSIZE;
4896 	}
4897 
4898 	nlmsg_end(skb, nlh);
4899 	return 0;
4900 }
4901 
4902 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
4903 			       struct inet6_fill_args *args)
4904 {
4905 	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
4906 	int ifindex = dev ? dev->ifindex : 1;
4907 	struct nlmsghdr  *nlh;
4908 	u8 scope = RT_SCOPE_UNIVERSE;
4909 
4910 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
4911 		scope = RT_SCOPE_SITE;
4912 
4913 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
4914 			sizeof(struct ifaddrmsg), args->flags);
4915 	if (!nlh)
4916 		return -EMSGSIZE;
4917 
4918 	if (args->netnsid >= 0 &&
4919 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
4920 		return -EMSGSIZE;
4921 
4922 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4923 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
4924 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
4925 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4926 		nlmsg_cancel(skb, nlh);
4927 		return -EMSGSIZE;
4928 	}
4929 
4930 	nlmsg_end(skb, nlh);
4931 	return 0;
4932 }
4933 
4934 enum addr_type_t {
4935 	UNICAST_ADDR,
4936 	MULTICAST_ADDR,
4937 	ANYCAST_ADDR,
4938 };
4939 
4940 /* called with rcu_read_lock() */
4941 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
4942 			  struct netlink_callback *cb, enum addr_type_t type,
4943 			  int s_ip_idx, int *p_ip_idx, int netnsid)
4944 {
4945 	struct inet6_fill_args fillargs = {
4946 		.portid = NETLINK_CB(cb->skb).portid,
4947 		.seq = cb->nlh->nlmsg_seq,
4948 		.flags = NLM_F_MULTI,
4949 		.netnsid = netnsid,
4950 	};
4951 	struct ifmcaddr6 *ifmca;
4952 	struct ifacaddr6 *ifaca;
4953 	int err = 1;
4954 	int ip_idx = *p_ip_idx;
4955 
4956 	read_lock_bh(&idev->lock);
4957 	switch (type) {
4958 	case UNICAST_ADDR: {
4959 		struct inet6_ifaddr *ifa;
4960 		fillargs.event = RTM_NEWADDR;
4961 
4962 		/* unicast address incl. temp addr */
4963 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
4964 			if (++ip_idx < s_ip_idx)
4965 				continue;
4966 			err = inet6_fill_ifaddr(skb, ifa, &fillargs);
4967 			if (err < 0)
4968 				break;
4969 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
4970 		}
4971 		break;
4972 	}
4973 	case MULTICAST_ADDR:
4974 		fillargs.event = RTM_GETMULTICAST;
4975 
4976 		/* multicast address */
4977 		for (ifmca = idev->mc_list; ifmca;
4978 		     ifmca = ifmca->next, ip_idx++) {
4979 			if (ip_idx < s_ip_idx)
4980 				continue;
4981 			err = inet6_fill_ifmcaddr(skb, ifmca, &fillargs);
4982 			if (err < 0)
4983 				break;
4984 		}
4985 		break;
4986 	case ANYCAST_ADDR:
4987 		fillargs.event = RTM_GETANYCAST;
4988 		/* anycast address */
4989 		for (ifaca = idev->ac_list; ifaca;
4990 		     ifaca = ifaca->aca_next, ip_idx++) {
4991 			if (ip_idx < s_ip_idx)
4992 				continue;
4993 			err = inet6_fill_ifacaddr(skb, ifaca, &fillargs);
4994 			if (err < 0)
4995 				break;
4996 		}
4997 		break;
4998 	default:
4999 		break;
5000 	}
5001 	read_unlock_bh(&idev->lock);
5002 	*p_ip_idx = ip_idx;
5003 	return err;
5004 }
5005 
5006 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
5007 			   enum addr_type_t type)
5008 {
5009 	struct net *net = sock_net(skb->sk);
5010 	struct nlattr *tb[IFA_MAX+1];
5011 	struct net *tgt_net = net;
5012 	int netnsid = -1;
5013 	int h, s_h;
5014 	int idx, ip_idx;
5015 	int s_idx, s_ip_idx;
5016 	struct net_device *dev;
5017 	struct inet6_dev *idev;
5018 	struct hlist_head *head;
5019 
5020 	s_h = cb->args[0];
5021 	s_idx = idx = cb->args[1];
5022 	s_ip_idx = ip_idx = cb->args[2];
5023 
5024 	if (nlmsg_parse(cb->nlh, sizeof(struct ifaddrmsg), tb, IFA_MAX,
5025 			ifa_ipv6_policy, NULL) >= 0) {
5026 		if (tb[IFA_TARGET_NETNSID]) {
5027 			netnsid = nla_get_s32(tb[IFA_TARGET_NETNSID]);
5028 
5029 			tgt_net = rtnl_get_net_ns_capable(skb->sk, netnsid);
5030 			if (IS_ERR(tgt_net))
5031 				return PTR_ERR(tgt_net);
5032 		}
5033 	}
5034 
5035 	rcu_read_lock();
5036 	cb->seq = atomic_read(&tgt_net->ipv6.dev_addr_genid) ^ tgt_net->dev_base_seq;
5037 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5038 		idx = 0;
5039 		head = &tgt_net->dev_index_head[h];
5040 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5041 			if (idx < s_idx)
5042 				goto cont;
5043 			if (h > s_h || idx > s_idx)
5044 				s_ip_idx = 0;
5045 			ip_idx = 0;
5046 			idev = __in6_dev_get(dev);
5047 			if (!idev)
5048 				goto cont;
5049 
5050 			if (in6_dump_addrs(idev, skb, cb, type,
5051 					   s_ip_idx, &ip_idx, netnsid) < 0)
5052 				goto done;
5053 cont:
5054 			idx++;
5055 		}
5056 	}
5057 done:
5058 	rcu_read_unlock();
5059 	cb->args[0] = h;
5060 	cb->args[1] = idx;
5061 	cb->args[2] = ip_idx;
5062 	if (netnsid >= 0)
5063 		put_net(tgt_net);
5064 
5065 	return skb->len;
5066 }
5067 
5068 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
5069 {
5070 	enum addr_type_t type = UNICAST_ADDR;
5071 
5072 	return inet6_dump_addr(skb, cb, type);
5073 }
5074 
5075 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
5076 {
5077 	enum addr_type_t type = MULTICAST_ADDR;
5078 
5079 	return inet6_dump_addr(skb, cb, type);
5080 }
5081 
5082 
5083 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
5084 {
5085 	enum addr_type_t type = ANYCAST_ADDR;
5086 
5087 	return inet6_dump_addr(skb, cb, type);
5088 }
5089 
5090 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5091 			     struct netlink_ext_ack *extack)
5092 {
5093 	struct net *net = sock_net(in_skb->sk);
5094 	struct inet6_fill_args fillargs = {
5095 		.portid = NETLINK_CB(in_skb).portid,
5096 		.seq = nlh->nlmsg_seq,
5097 		.event = RTM_NEWADDR,
5098 		.flags = 0,
5099 		.netnsid = -1,
5100 	};
5101 	struct net *tgt_net = net;
5102 	struct ifaddrmsg *ifm;
5103 	struct nlattr *tb[IFA_MAX+1];
5104 	struct in6_addr *addr = NULL, *peer;
5105 	struct net_device *dev = NULL;
5106 	struct inet6_ifaddr *ifa;
5107 	struct sk_buff *skb;
5108 	int err;
5109 
5110 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
5111 			  extack);
5112 	if (err < 0)
5113 		return err;
5114 
5115 	if (tb[IFA_TARGET_NETNSID]) {
5116 		fillargs.netnsid = nla_get_s32(tb[IFA_TARGET_NETNSID]);
5117 
5118 		tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(in_skb).sk,
5119 						  fillargs.netnsid);
5120 		if (IS_ERR(tgt_net))
5121 			return PTR_ERR(tgt_net);
5122 	}
5123 
5124 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
5125 	if (!addr)
5126 		return -EINVAL;
5127 
5128 	ifm = nlmsg_data(nlh);
5129 	if (ifm->ifa_index)
5130 		dev = dev_get_by_index(tgt_net, ifm->ifa_index);
5131 
5132 	ifa = ipv6_get_ifaddr(tgt_net, addr, dev, 1);
5133 	if (!ifa) {
5134 		err = -EADDRNOTAVAIL;
5135 		goto errout;
5136 	}
5137 
5138 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
5139 	if (!skb) {
5140 		err = -ENOBUFS;
5141 		goto errout_ifa;
5142 	}
5143 
5144 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5145 	if (err < 0) {
5146 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5147 		WARN_ON(err == -EMSGSIZE);
5148 		kfree_skb(skb);
5149 		goto errout_ifa;
5150 	}
5151 	err = rtnl_unicast(skb, tgt_net, NETLINK_CB(in_skb).portid);
5152 errout_ifa:
5153 	in6_ifa_put(ifa);
5154 errout:
5155 	if (dev)
5156 		dev_put(dev);
5157 	if (fillargs.netnsid >= 0)
5158 		put_net(tgt_net);
5159 
5160 	return err;
5161 }
5162 
5163 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
5164 {
5165 	struct sk_buff *skb;
5166 	struct net *net = dev_net(ifa->idev->dev);
5167 	struct inet6_fill_args fillargs = {
5168 		.portid = 0,
5169 		.seq = 0,
5170 		.event = event,
5171 		.flags = 0,
5172 		.netnsid = -1,
5173 	};
5174 	int err = -ENOBUFS;
5175 
5176 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
5177 	if (!skb)
5178 		goto errout;
5179 
5180 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5181 	if (err < 0) {
5182 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5183 		WARN_ON(err == -EMSGSIZE);
5184 		kfree_skb(skb);
5185 		goto errout;
5186 	}
5187 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5188 	return;
5189 errout:
5190 	if (err < 0)
5191 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5192 }
5193 
5194 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
5195 				__s32 *array, int bytes)
5196 {
5197 	BUG_ON(bytes < (DEVCONF_MAX * 4));
5198 
5199 	memset(array, 0, bytes);
5200 	array[DEVCONF_FORWARDING] = cnf->forwarding;
5201 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
5202 	array[DEVCONF_MTU6] = cnf->mtu6;
5203 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
5204 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
5205 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
5206 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
5207 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
5208 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5209 		jiffies_to_msecs(cnf->rtr_solicit_interval);
5210 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5211 		jiffies_to_msecs(cnf->rtr_solicit_max_interval);
5212 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5213 		jiffies_to_msecs(cnf->rtr_solicit_delay);
5214 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
5215 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5216 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
5217 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5218 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
5219 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
5220 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
5221 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
5222 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
5223 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
5224 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
5225 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
5226 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] = cnf->accept_ra_min_hop_limit;
5227 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
5228 #ifdef CONFIG_IPV6_ROUTER_PREF
5229 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
5230 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5231 		jiffies_to_msecs(cnf->rtr_probe_interval);
5232 #ifdef CONFIG_IPV6_ROUTE_INFO
5233 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] = cnf->accept_ra_rt_info_min_plen;
5234 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
5235 #endif
5236 #endif
5237 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
5238 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
5239 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5240 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
5241 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
5242 #endif
5243 #ifdef CONFIG_IPV6_MROUTE
5244 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
5245 #endif
5246 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
5247 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
5248 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
5249 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
5250 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
5251 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
5252 	array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
5253 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] = cnf->ignore_routes_with_linkdown;
5254 	/* we omit DEVCONF_STABLE_SECRET for now */
5255 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
5256 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
5257 	array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
5258 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
5259 	array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
5260 #ifdef CONFIG_IPV6_SEG6_HMAC
5261 	array[DEVCONF_SEG6_REQUIRE_HMAC] = cnf->seg6_require_hmac;
5262 #endif
5263 	array[DEVCONF_ENHANCED_DAD] = cnf->enhanced_dad;
5264 	array[DEVCONF_ADDR_GEN_MODE] = cnf->addr_gen_mode;
5265 	array[DEVCONF_DISABLE_POLICY] = cnf->disable_policy;
5266 	array[DEVCONF_NDISC_TCLASS] = cnf->ndisc_tclass;
5267 }
5268 
5269 static inline size_t inet6_ifla6_size(void)
5270 {
5271 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5272 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5273 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5274 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5275 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5276 	     + nla_total_size(sizeof(struct in6_addr)) /* IFLA_INET6_TOKEN */
5277 	     + nla_total_size(1) /* IFLA_INET6_ADDR_GEN_MODE */
5278 	     + 0;
5279 }
5280 
5281 static inline size_t inet6_if_nlmsg_size(void)
5282 {
5283 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5284 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5285 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5286 	       + nla_total_size(4) /* IFLA_MTU */
5287 	       + nla_total_size(4) /* IFLA_LINK */
5288 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5289 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5290 }
5291 
5292 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5293 					int bytes)
5294 {
5295 	int i;
5296 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5297 	BUG_ON(pad < 0);
5298 
5299 	/* Use put_unaligned() because stats may not be aligned for u64. */
5300 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5301 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5302 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5303 
5304 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5305 }
5306 
5307 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5308 					int bytes, size_t syncpoff)
5309 {
5310 	int i, c;
5311 	u64 buff[IPSTATS_MIB_MAX];
5312 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5313 
5314 	BUG_ON(pad < 0);
5315 
5316 	memset(buff, 0, sizeof(buff));
5317 	buff[0] = IPSTATS_MIB_MAX;
5318 
5319 	for_each_possible_cpu(c) {
5320 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5321 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5322 	}
5323 
5324 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5325 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5326 }
5327 
5328 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5329 			     int bytes)
5330 {
5331 	switch (attrtype) {
5332 	case IFLA_INET6_STATS:
5333 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5334 				     offsetof(struct ipstats_mib, syncp));
5335 		break;
5336 	case IFLA_INET6_ICMP6STATS:
5337 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5338 		break;
5339 	}
5340 }
5341 
5342 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5343 				  u32 ext_filter_mask)
5344 {
5345 	struct nlattr *nla;
5346 	struct ifla_cacheinfo ci;
5347 
5348 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
5349 		goto nla_put_failure;
5350 	ci.max_reasm_len = IPV6_MAXPLEN;
5351 	ci.tstamp = cstamp_delta(idev->tstamp);
5352 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5353 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5354 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5355 		goto nla_put_failure;
5356 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5357 	if (!nla)
5358 		goto nla_put_failure;
5359 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5360 
5361 	/* XXX - MC not implemented */
5362 
5363 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5364 		return 0;
5365 
5366 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5367 	if (!nla)
5368 		goto nla_put_failure;
5369 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5370 
5371 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5372 	if (!nla)
5373 		goto nla_put_failure;
5374 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5375 
5376 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5377 	if (!nla)
5378 		goto nla_put_failure;
5379 
5380 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->cnf.addr_gen_mode))
5381 		goto nla_put_failure;
5382 
5383 	read_lock_bh(&idev->lock);
5384 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5385 	read_unlock_bh(&idev->lock);
5386 
5387 	return 0;
5388 
5389 nla_put_failure:
5390 	return -EMSGSIZE;
5391 }
5392 
5393 static size_t inet6_get_link_af_size(const struct net_device *dev,
5394 				     u32 ext_filter_mask)
5395 {
5396 	if (!__in6_dev_get(dev))
5397 		return 0;
5398 
5399 	return inet6_ifla6_size();
5400 }
5401 
5402 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5403 			      u32 ext_filter_mask)
5404 {
5405 	struct inet6_dev *idev = __in6_dev_get(dev);
5406 
5407 	if (!idev)
5408 		return -ENODATA;
5409 
5410 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5411 		return -EMSGSIZE;
5412 
5413 	return 0;
5414 }
5415 
5416 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
5417 {
5418 	struct inet6_ifaddr *ifp;
5419 	struct net_device *dev = idev->dev;
5420 	bool clear_token, update_rs = false;
5421 	struct in6_addr ll_addr;
5422 
5423 	ASSERT_RTNL();
5424 
5425 	if (!token)
5426 		return -EINVAL;
5427 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
5428 		return -EINVAL;
5429 	if (!ipv6_accept_ra(idev))
5430 		return -EINVAL;
5431 	if (idev->cnf.rtr_solicits == 0)
5432 		return -EINVAL;
5433 
5434 	write_lock_bh(&idev->lock);
5435 
5436 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5437 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5438 
5439 	write_unlock_bh(&idev->lock);
5440 
5441 	clear_token = ipv6_addr_any(token);
5442 	if (clear_token)
5443 		goto update_lft;
5444 
5445 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5446 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5447 			     IFA_F_OPTIMISTIC)) {
5448 		/* If we're not ready, then normal ifup will take care
5449 		 * of this. Otherwise, we need to request our rs here.
5450 		 */
5451 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5452 		update_rs = true;
5453 	}
5454 
5455 update_lft:
5456 	write_lock_bh(&idev->lock);
5457 
5458 	if (update_rs) {
5459 		idev->if_flags |= IF_RS_SENT;
5460 		idev->rs_interval = rfc3315_s14_backoff_init(
5461 			idev->cnf.rtr_solicit_interval);
5462 		idev->rs_probes = 1;
5463 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5464 	}
5465 
5466 	/* Well, that's kinda nasty ... */
5467 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5468 		spin_lock(&ifp->lock);
5469 		if (ifp->tokenized) {
5470 			ifp->valid_lft = 0;
5471 			ifp->prefered_lft = 0;
5472 		}
5473 		spin_unlock(&ifp->lock);
5474 	}
5475 
5476 	write_unlock_bh(&idev->lock);
5477 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5478 	addrconf_verify_rtnl();
5479 	return 0;
5480 }
5481 
5482 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5483 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5484 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5485 };
5486 
5487 static int inet6_validate_link_af(const struct net_device *dev,
5488 				  const struct nlattr *nla)
5489 {
5490 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5491 
5492 	if (dev && !__in6_dev_get(dev))
5493 		return -EAFNOSUPPORT;
5494 
5495 	return nla_parse_nested(tb, IFLA_INET6_MAX, nla, inet6_af_policy,
5496 				NULL);
5497 }
5498 
5499 static int check_addr_gen_mode(int mode)
5500 {
5501 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5502 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5503 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5504 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5505 		return -EINVAL;
5506 	return 1;
5507 }
5508 
5509 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5510 				int mode)
5511 {
5512 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5513 	    !idev->cnf.stable_secret.initialized &&
5514 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5515 		return -EINVAL;
5516 	return 1;
5517 }
5518 
5519 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
5520 {
5521 	int err = -EINVAL;
5522 	struct inet6_dev *idev = __in6_dev_get(dev);
5523 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5524 
5525 	if (!idev)
5526 		return -EAFNOSUPPORT;
5527 
5528 	if (nla_parse_nested(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
5529 		BUG();
5530 
5531 	if (tb[IFLA_INET6_TOKEN]) {
5532 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
5533 		if (err)
5534 			return err;
5535 	}
5536 
5537 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5538 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5539 
5540 		if (check_addr_gen_mode(mode) < 0 ||
5541 		    check_stable_privacy(idev, dev_net(dev), mode) < 0)
5542 			return -EINVAL;
5543 
5544 		idev->cnf.addr_gen_mode = mode;
5545 		err = 0;
5546 	}
5547 
5548 	return err;
5549 }
5550 
5551 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
5552 			     u32 portid, u32 seq, int event, unsigned int flags)
5553 {
5554 	struct net_device *dev = idev->dev;
5555 	struct ifinfomsg *hdr;
5556 	struct nlmsghdr *nlh;
5557 	void *protoinfo;
5558 
5559 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
5560 	if (!nlh)
5561 		return -EMSGSIZE;
5562 
5563 	hdr = nlmsg_data(nlh);
5564 	hdr->ifi_family = AF_INET6;
5565 	hdr->__ifi_pad = 0;
5566 	hdr->ifi_type = dev->type;
5567 	hdr->ifi_index = dev->ifindex;
5568 	hdr->ifi_flags = dev_get_flags(dev);
5569 	hdr->ifi_change = 0;
5570 
5571 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
5572 	    (dev->addr_len &&
5573 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
5574 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
5575 	    (dev->ifindex != dev_get_iflink(dev) &&
5576 	     nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))) ||
5577 	    nla_put_u8(skb, IFLA_OPERSTATE,
5578 		       netif_running(dev) ? dev->operstate : IF_OPER_DOWN))
5579 		goto nla_put_failure;
5580 	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
5581 	if (!protoinfo)
5582 		goto nla_put_failure;
5583 
5584 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
5585 		goto nla_put_failure;
5586 
5587 	nla_nest_end(skb, protoinfo);
5588 	nlmsg_end(skb, nlh);
5589 	return 0;
5590 
5591 nla_put_failure:
5592 	nlmsg_cancel(skb, nlh);
5593 	return -EMSGSIZE;
5594 }
5595 
5596 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
5597 {
5598 	struct net *net = sock_net(skb->sk);
5599 	int h, s_h;
5600 	int idx = 0, s_idx;
5601 	struct net_device *dev;
5602 	struct inet6_dev *idev;
5603 	struct hlist_head *head;
5604 
5605 	s_h = cb->args[0];
5606 	s_idx = cb->args[1];
5607 
5608 	rcu_read_lock();
5609 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5610 		idx = 0;
5611 		head = &net->dev_index_head[h];
5612 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5613 			if (idx < s_idx)
5614 				goto cont;
5615 			idev = __in6_dev_get(dev);
5616 			if (!idev)
5617 				goto cont;
5618 			if (inet6_fill_ifinfo(skb, idev,
5619 					      NETLINK_CB(cb->skb).portid,
5620 					      cb->nlh->nlmsg_seq,
5621 					      RTM_NEWLINK, NLM_F_MULTI) < 0)
5622 				goto out;
5623 cont:
5624 			idx++;
5625 		}
5626 	}
5627 out:
5628 	rcu_read_unlock();
5629 	cb->args[1] = idx;
5630 	cb->args[0] = h;
5631 
5632 	return skb->len;
5633 }
5634 
5635 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
5636 {
5637 	struct sk_buff *skb;
5638 	struct net *net = dev_net(idev->dev);
5639 	int err = -ENOBUFS;
5640 
5641 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
5642 	if (!skb)
5643 		goto errout;
5644 
5645 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
5646 	if (err < 0) {
5647 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
5648 		WARN_ON(err == -EMSGSIZE);
5649 		kfree_skb(skb);
5650 		goto errout;
5651 	}
5652 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
5653 	return;
5654 errout:
5655 	if (err < 0)
5656 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
5657 }
5658 
5659 static inline size_t inet6_prefix_nlmsg_size(void)
5660 {
5661 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
5662 	       + nla_total_size(sizeof(struct in6_addr))
5663 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
5664 }
5665 
5666 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
5667 			     struct prefix_info *pinfo, u32 portid, u32 seq,
5668 			     int event, unsigned int flags)
5669 {
5670 	struct prefixmsg *pmsg;
5671 	struct nlmsghdr *nlh;
5672 	struct prefix_cacheinfo	ci;
5673 
5674 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
5675 	if (!nlh)
5676 		return -EMSGSIZE;
5677 
5678 	pmsg = nlmsg_data(nlh);
5679 	pmsg->prefix_family = AF_INET6;
5680 	pmsg->prefix_pad1 = 0;
5681 	pmsg->prefix_pad2 = 0;
5682 	pmsg->prefix_ifindex = idev->dev->ifindex;
5683 	pmsg->prefix_len = pinfo->prefix_len;
5684 	pmsg->prefix_type = pinfo->type;
5685 	pmsg->prefix_pad3 = 0;
5686 	pmsg->prefix_flags = 0;
5687 	if (pinfo->onlink)
5688 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
5689 	if (pinfo->autoconf)
5690 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
5691 
5692 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
5693 		goto nla_put_failure;
5694 	ci.preferred_time = ntohl(pinfo->prefered);
5695 	ci.valid_time = ntohl(pinfo->valid);
5696 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
5697 		goto nla_put_failure;
5698 	nlmsg_end(skb, nlh);
5699 	return 0;
5700 
5701 nla_put_failure:
5702 	nlmsg_cancel(skb, nlh);
5703 	return -EMSGSIZE;
5704 }
5705 
5706 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
5707 			 struct prefix_info *pinfo)
5708 {
5709 	struct sk_buff *skb;
5710 	struct net *net = dev_net(idev->dev);
5711 	int err = -ENOBUFS;
5712 
5713 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
5714 	if (!skb)
5715 		goto errout;
5716 
5717 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
5718 	if (err < 0) {
5719 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
5720 		WARN_ON(err == -EMSGSIZE);
5721 		kfree_skb(skb);
5722 		goto errout;
5723 	}
5724 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
5725 	return;
5726 errout:
5727 	if (err < 0)
5728 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
5729 }
5730 
5731 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5732 {
5733 	struct net *net = dev_net(ifp->idev->dev);
5734 
5735 	if (event)
5736 		ASSERT_RTNL();
5737 
5738 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
5739 
5740 	switch (event) {
5741 	case RTM_NEWADDR:
5742 		/*
5743 		 * If the address was optimistic
5744 		 * we inserted the route at the start of
5745 		 * our DAD process, so we don't need
5746 		 * to do it again
5747 		 */
5748 		if (!rcu_access_pointer(ifp->rt->fib6_node))
5749 			ip6_ins_rt(net, ifp->rt);
5750 		if (ifp->idev->cnf.forwarding)
5751 			addrconf_join_anycast(ifp);
5752 		if (!ipv6_addr_any(&ifp->peer_addr))
5753 			addrconf_prefix_route(&ifp->peer_addr, 128, 0,
5754 					      ifp->idev->dev, 0, 0,
5755 					      GFP_ATOMIC);
5756 		break;
5757 	case RTM_DELADDR:
5758 		if (ifp->idev->cnf.forwarding)
5759 			addrconf_leave_anycast(ifp);
5760 		addrconf_leave_solict(ifp->idev, &ifp->addr);
5761 		if (!ipv6_addr_any(&ifp->peer_addr)) {
5762 			struct fib6_info *rt;
5763 
5764 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
5765 						       ifp->idev->dev, 0, 0);
5766 			if (rt)
5767 				ip6_del_rt(net, rt);
5768 		}
5769 		if (ifp->rt) {
5770 			ip6_del_rt(net, ifp->rt);
5771 			ifp->rt = NULL;
5772 		}
5773 		rt_genid_bump_ipv6(net);
5774 		break;
5775 	}
5776 	atomic_inc(&net->ipv6.dev_addr_genid);
5777 }
5778 
5779 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5780 {
5781 	rcu_read_lock_bh();
5782 	if (likely(ifp->idev->dead == 0))
5783 		__ipv6_ifa_notify(event, ifp);
5784 	rcu_read_unlock_bh();
5785 }
5786 
5787 #ifdef CONFIG_SYSCTL
5788 
5789 static
5790 int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
5791 			   void __user *buffer, size_t *lenp, loff_t *ppos)
5792 {
5793 	int *valp = ctl->data;
5794 	int val = *valp;
5795 	loff_t pos = *ppos;
5796 	struct ctl_table lctl;
5797 	int ret;
5798 
5799 	/*
5800 	 * ctl->data points to idev->cnf.forwarding, we should
5801 	 * not modify it until we get the rtnl lock.
5802 	 */
5803 	lctl = *ctl;
5804 	lctl.data = &val;
5805 
5806 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5807 
5808 	if (write)
5809 		ret = addrconf_fixup_forwarding(ctl, valp, val);
5810 	if (ret)
5811 		*ppos = pos;
5812 	return ret;
5813 }
5814 
5815 static
5816 int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
5817 			void __user *buffer, size_t *lenp, loff_t *ppos)
5818 {
5819 	struct inet6_dev *idev = ctl->extra1;
5820 	int min_mtu = IPV6_MIN_MTU;
5821 	struct ctl_table lctl;
5822 
5823 	lctl = *ctl;
5824 	lctl.extra1 = &min_mtu;
5825 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
5826 
5827 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
5828 }
5829 
5830 static void dev_disable_change(struct inet6_dev *idev)
5831 {
5832 	struct netdev_notifier_info info;
5833 
5834 	if (!idev || !idev->dev)
5835 		return;
5836 
5837 	netdev_notifier_info_init(&info, idev->dev);
5838 	if (idev->cnf.disable_ipv6)
5839 		addrconf_notify(NULL, NETDEV_DOWN, &info);
5840 	else
5841 		addrconf_notify(NULL, NETDEV_UP, &info);
5842 }
5843 
5844 static void addrconf_disable_change(struct net *net, __s32 newf)
5845 {
5846 	struct net_device *dev;
5847 	struct inet6_dev *idev;
5848 
5849 	for_each_netdev(net, dev) {
5850 		idev = __in6_dev_get(dev);
5851 		if (idev) {
5852 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
5853 			idev->cnf.disable_ipv6 = newf;
5854 			if (changed)
5855 				dev_disable_change(idev);
5856 		}
5857 	}
5858 }
5859 
5860 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
5861 {
5862 	struct net *net;
5863 	int old;
5864 
5865 	if (!rtnl_trylock())
5866 		return restart_syscall();
5867 
5868 	net = (struct net *)table->extra2;
5869 	old = *p;
5870 	*p = newf;
5871 
5872 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
5873 		rtnl_unlock();
5874 		return 0;
5875 	}
5876 
5877 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
5878 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
5879 		addrconf_disable_change(net, newf);
5880 	} else if ((!newf) ^ (!old))
5881 		dev_disable_change((struct inet6_dev *)table->extra1);
5882 
5883 	rtnl_unlock();
5884 	return 0;
5885 }
5886 
5887 static
5888 int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
5889 			    void __user *buffer, size_t *lenp, loff_t *ppos)
5890 {
5891 	int *valp = ctl->data;
5892 	int val = *valp;
5893 	loff_t pos = *ppos;
5894 	struct ctl_table lctl;
5895 	int ret;
5896 
5897 	/*
5898 	 * ctl->data points to idev->cnf.disable_ipv6, we should
5899 	 * not modify it until we get the rtnl lock.
5900 	 */
5901 	lctl = *ctl;
5902 	lctl.data = &val;
5903 
5904 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
5905 
5906 	if (write)
5907 		ret = addrconf_disable_ipv6(ctl, valp, val);
5908 	if (ret)
5909 		*ppos = pos;
5910 	return ret;
5911 }
5912 
5913 static
5914 int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
5915 			      void __user *buffer, size_t *lenp, loff_t *ppos)
5916 {
5917 	int *valp = ctl->data;
5918 	int ret;
5919 	int old, new;
5920 
5921 	old = *valp;
5922 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
5923 	new = *valp;
5924 
5925 	if (write && old != new) {
5926 		struct net *net = ctl->extra2;
5927 
5928 		if (!rtnl_trylock())
5929 			return restart_syscall();
5930 
5931 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
5932 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
5933 						     NETCONFA_PROXY_NEIGH,
5934 						     NETCONFA_IFINDEX_DEFAULT,
5935 						     net->ipv6.devconf_dflt);
5936 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
5937 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
5938 						     NETCONFA_PROXY_NEIGH,
5939 						     NETCONFA_IFINDEX_ALL,
5940 						     net->ipv6.devconf_all);
5941 		else {
5942 			struct inet6_dev *idev = ctl->extra1;
5943 
5944 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
5945 						     NETCONFA_PROXY_NEIGH,
5946 						     idev->dev->ifindex,
5947 						     &idev->cnf);
5948 		}
5949 		rtnl_unlock();
5950 	}
5951 
5952 	return ret;
5953 }
5954 
5955 static int addrconf_sysctl_addr_gen_mode(struct ctl_table *ctl, int write,
5956 					 void __user *buffer, size_t *lenp,
5957 					 loff_t *ppos)
5958 {
5959 	int ret = 0;
5960 	u32 new_val;
5961 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
5962 	struct net *net = (struct net *)ctl->extra2;
5963 	struct ctl_table tmp = {
5964 		.data = &new_val,
5965 		.maxlen = sizeof(new_val),
5966 		.mode = ctl->mode,
5967 	};
5968 
5969 	if (!rtnl_trylock())
5970 		return restart_syscall();
5971 
5972 	new_val = *((u32 *)ctl->data);
5973 
5974 	ret = proc_douintvec(&tmp, write, buffer, lenp, ppos);
5975 	if (ret != 0)
5976 		goto out;
5977 
5978 	if (write) {
5979 		if (check_addr_gen_mode(new_val) < 0) {
5980 			ret = -EINVAL;
5981 			goto out;
5982 		}
5983 
5984 		if (idev) {
5985 			if (check_stable_privacy(idev, net, new_val) < 0) {
5986 				ret = -EINVAL;
5987 				goto out;
5988 			}
5989 
5990 			if (idev->cnf.addr_gen_mode != new_val) {
5991 				idev->cnf.addr_gen_mode = new_val;
5992 				addrconf_dev_config(idev->dev);
5993 			}
5994 		} else if (&net->ipv6.devconf_all->addr_gen_mode == ctl->data) {
5995 			struct net_device *dev;
5996 
5997 			net->ipv6.devconf_dflt->addr_gen_mode = new_val;
5998 			for_each_netdev(net, dev) {
5999 				idev = __in6_dev_get(dev);
6000 				if (idev &&
6001 				    idev->cnf.addr_gen_mode != new_val) {
6002 					idev->cnf.addr_gen_mode = new_val;
6003 					addrconf_dev_config(idev->dev);
6004 				}
6005 			}
6006 		}
6007 
6008 		*((u32 *)ctl->data) = new_val;
6009 	}
6010 
6011 out:
6012 	rtnl_unlock();
6013 
6014 	return ret;
6015 }
6016 
6017 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
6018 					 void __user *buffer, size_t *lenp,
6019 					 loff_t *ppos)
6020 {
6021 	int err;
6022 	struct in6_addr addr;
6023 	char str[IPV6_MAX_STRLEN];
6024 	struct ctl_table lctl = *ctl;
6025 	struct net *net = ctl->extra2;
6026 	struct ipv6_stable_secret *secret = ctl->data;
6027 
6028 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
6029 		return -EIO;
6030 
6031 	lctl.maxlen = IPV6_MAX_STRLEN;
6032 	lctl.data = str;
6033 
6034 	if (!rtnl_trylock())
6035 		return restart_syscall();
6036 
6037 	if (!write && !secret->initialized) {
6038 		err = -EIO;
6039 		goto out;
6040 	}
6041 
6042 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
6043 	if (err >= sizeof(str)) {
6044 		err = -EIO;
6045 		goto out;
6046 	}
6047 
6048 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
6049 	if (err || !write)
6050 		goto out;
6051 
6052 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
6053 		err = -EIO;
6054 		goto out;
6055 	}
6056 
6057 	secret->initialized = true;
6058 	secret->secret = addr;
6059 
6060 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
6061 		struct net_device *dev;
6062 
6063 		for_each_netdev(net, dev) {
6064 			struct inet6_dev *idev = __in6_dev_get(dev);
6065 
6066 			if (idev) {
6067 				idev->cnf.addr_gen_mode =
6068 					IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6069 			}
6070 		}
6071 	} else {
6072 		struct inet6_dev *idev = ctl->extra1;
6073 
6074 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6075 	}
6076 
6077 out:
6078 	rtnl_unlock();
6079 
6080 	return err;
6081 }
6082 
6083 static
6084 int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
6085 						int write,
6086 						void __user *buffer,
6087 						size_t *lenp,
6088 						loff_t *ppos)
6089 {
6090 	int *valp = ctl->data;
6091 	int val = *valp;
6092 	loff_t pos = *ppos;
6093 	struct ctl_table lctl;
6094 	int ret;
6095 
6096 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
6097 	 * we should not modify it until we get the rtnl lock.
6098 	 */
6099 	lctl = *ctl;
6100 	lctl.data = &val;
6101 
6102 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6103 
6104 	if (write)
6105 		ret = addrconf_fixup_linkdown(ctl, valp, val);
6106 	if (ret)
6107 		*ppos = pos;
6108 	return ret;
6109 }
6110 
6111 static
6112 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
6113 {
6114 	if (rt) {
6115 		if (action)
6116 			rt->dst.flags |= DST_NOPOLICY;
6117 		else
6118 			rt->dst.flags &= ~DST_NOPOLICY;
6119 	}
6120 }
6121 
6122 static
6123 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
6124 {
6125 	struct inet6_ifaddr *ifa;
6126 
6127 	read_lock_bh(&idev->lock);
6128 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
6129 		spin_lock(&ifa->lock);
6130 		if (ifa->rt) {
6131 			struct fib6_info *rt = ifa->rt;
6132 			int cpu;
6133 
6134 			rcu_read_lock();
6135 			ifa->rt->dst_nopolicy = val ? true : false;
6136 			if (rt->rt6i_pcpu) {
6137 				for_each_possible_cpu(cpu) {
6138 					struct rt6_info **rtp;
6139 
6140 					rtp = per_cpu_ptr(rt->rt6i_pcpu, cpu);
6141 					addrconf_set_nopolicy(*rtp, val);
6142 				}
6143 			}
6144 			rcu_read_unlock();
6145 		}
6146 		spin_unlock(&ifa->lock);
6147 	}
6148 	read_unlock_bh(&idev->lock);
6149 }
6150 
6151 static
6152 int addrconf_disable_policy(struct ctl_table *ctl, int *valp, int val)
6153 {
6154 	struct inet6_dev *idev;
6155 	struct net *net;
6156 
6157 	if (!rtnl_trylock())
6158 		return restart_syscall();
6159 
6160 	*valp = val;
6161 
6162 	net = (struct net *)ctl->extra2;
6163 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
6164 		rtnl_unlock();
6165 		return 0;
6166 	}
6167 
6168 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
6169 		struct net_device *dev;
6170 
6171 		for_each_netdev(net, dev) {
6172 			idev = __in6_dev_get(dev);
6173 			if (idev)
6174 				addrconf_disable_policy_idev(idev, val);
6175 		}
6176 	} else {
6177 		idev = (struct inet6_dev *)ctl->extra1;
6178 		addrconf_disable_policy_idev(idev, val);
6179 	}
6180 
6181 	rtnl_unlock();
6182 	return 0;
6183 }
6184 
6185 static
6186 int addrconf_sysctl_disable_policy(struct ctl_table *ctl, int write,
6187 				   void __user *buffer, size_t *lenp,
6188 				   loff_t *ppos)
6189 {
6190 	int *valp = ctl->data;
6191 	int val = *valp;
6192 	loff_t pos = *ppos;
6193 	struct ctl_table lctl;
6194 	int ret;
6195 
6196 	lctl = *ctl;
6197 	lctl.data = &val;
6198 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6199 
6200 	if (write && (*valp != val))
6201 		ret = addrconf_disable_policy(ctl, valp, val);
6202 
6203 	if (ret)
6204 		*ppos = pos;
6205 
6206 	return ret;
6207 }
6208 
6209 static int minus_one = -1;
6210 static const int zero = 0;
6211 static const int one = 1;
6212 static const int two_five_five = 255;
6213 
6214 static const struct ctl_table addrconf_sysctl[] = {
6215 	{
6216 		.procname	= "forwarding",
6217 		.data		= &ipv6_devconf.forwarding,
6218 		.maxlen		= sizeof(int),
6219 		.mode		= 0644,
6220 		.proc_handler	= addrconf_sysctl_forward,
6221 	},
6222 	{
6223 		.procname	= "hop_limit",
6224 		.data		= &ipv6_devconf.hop_limit,
6225 		.maxlen		= sizeof(int),
6226 		.mode		= 0644,
6227 		.proc_handler	= proc_dointvec_minmax,
6228 		.extra1		= (void *)&one,
6229 		.extra2		= (void *)&two_five_five,
6230 	},
6231 	{
6232 		.procname	= "mtu",
6233 		.data		= &ipv6_devconf.mtu6,
6234 		.maxlen		= sizeof(int),
6235 		.mode		= 0644,
6236 		.proc_handler	= addrconf_sysctl_mtu,
6237 	},
6238 	{
6239 		.procname	= "accept_ra",
6240 		.data		= &ipv6_devconf.accept_ra,
6241 		.maxlen		= sizeof(int),
6242 		.mode		= 0644,
6243 		.proc_handler	= proc_dointvec,
6244 	},
6245 	{
6246 		.procname	= "accept_redirects",
6247 		.data		= &ipv6_devconf.accept_redirects,
6248 		.maxlen		= sizeof(int),
6249 		.mode		= 0644,
6250 		.proc_handler	= proc_dointvec,
6251 	},
6252 	{
6253 		.procname	= "autoconf",
6254 		.data		= &ipv6_devconf.autoconf,
6255 		.maxlen		= sizeof(int),
6256 		.mode		= 0644,
6257 		.proc_handler	= proc_dointvec,
6258 	},
6259 	{
6260 		.procname	= "dad_transmits",
6261 		.data		= &ipv6_devconf.dad_transmits,
6262 		.maxlen		= sizeof(int),
6263 		.mode		= 0644,
6264 		.proc_handler	= proc_dointvec,
6265 	},
6266 	{
6267 		.procname	= "router_solicitations",
6268 		.data		= &ipv6_devconf.rtr_solicits,
6269 		.maxlen		= sizeof(int),
6270 		.mode		= 0644,
6271 		.proc_handler	= proc_dointvec_minmax,
6272 		.extra1		= &minus_one,
6273 	},
6274 	{
6275 		.procname	= "router_solicitation_interval",
6276 		.data		= &ipv6_devconf.rtr_solicit_interval,
6277 		.maxlen		= sizeof(int),
6278 		.mode		= 0644,
6279 		.proc_handler	= proc_dointvec_jiffies,
6280 	},
6281 	{
6282 		.procname	= "router_solicitation_max_interval",
6283 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6284 		.maxlen		= sizeof(int),
6285 		.mode		= 0644,
6286 		.proc_handler	= proc_dointvec_jiffies,
6287 	},
6288 	{
6289 		.procname	= "router_solicitation_delay",
6290 		.data		= &ipv6_devconf.rtr_solicit_delay,
6291 		.maxlen		= sizeof(int),
6292 		.mode		= 0644,
6293 		.proc_handler	= proc_dointvec_jiffies,
6294 	},
6295 	{
6296 		.procname	= "force_mld_version",
6297 		.data		= &ipv6_devconf.force_mld_version,
6298 		.maxlen		= sizeof(int),
6299 		.mode		= 0644,
6300 		.proc_handler	= proc_dointvec,
6301 	},
6302 	{
6303 		.procname	= "mldv1_unsolicited_report_interval",
6304 		.data		=
6305 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6306 		.maxlen		= sizeof(int),
6307 		.mode		= 0644,
6308 		.proc_handler	= proc_dointvec_ms_jiffies,
6309 	},
6310 	{
6311 		.procname	= "mldv2_unsolicited_report_interval",
6312 		.data		=
6313 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6314 		.maxlen		= sizeof(int),
6315 		.mode		= 0644,
6316 		.proc_handler	= proc_dointvec_ms_jiffies,
6317 	},
6318 	{
6319 		.procname	= "use_tempaddr",
6320 		.data		= &ipv6_devconf.use_tempaddr,
6321 		.maxlen		= sizeof(int),
6322 		.mode		= 0644,
6323 		.proc_handler	= proc_dointvec,
6324 	},
6325 	{
6326 		.procname	= "temp_valid_lft",
6327 		.data		= &ipv6_devconf.temp_valid_lft,
6328 		.maxlen		= sizeof(int),
6329 		.mode		= 0644,
6330 		.proc_handler	= proc_dointvec,
6331 	},
6332 	{
6333 		.procname	= "temp_prefered_lft",
6334 		.data		= &ipv6_devconf.temp_prefered_lft,
6335 		.maxlen		= sizeof(int),
6336 		.mode		= 0644,
6337 		.proc_handler	= proc_dointvec,
6338 	},
6339 	{
6340 		.procname	= "regen_max_retry",
6341 		.data		= &ipv6_devconf.regen_max_retry,
6342 		.maxlen		= sizeof(int),
6343 		.mode		= 0644,
6344 		.proc_handler	= proc_dointvec,
6345 	},
6346 	{
6347 		.procname	= "max_desync_factor",
6348 		.data		= &ipv6_devconf.max_desync_factor,
6349 		.maxlen		= sizeof(int),
6350 		.mode		= 0644,
6351 		.proc_handler	= proc_dointvec,
6352 	},
6353 	{
6354 		.procname	= "max_addresses",
6355 		.data		= &ipv6_devconf.max_addresses,
6356 		.maxlen		= sizeof(int),
6357 		.mode		= 0644,
6358 		.proc_handler	= proc_dointvec,
6359 	},
6360 	{
6361 		.procname	= "accept_ra_defrtr",
6362 		.data		= &ipv6_devconf.accept_ra_defrtr,
6363 		.maxlen		= sizeof(int),
6364 		.mode		= 0644,
6365 		.proc_handler	= proc_dointvec,
6366 	},
6367 	{
6368 		.procname	= "accept_ra_min_hop_limit",
6369 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6370 		.maxlen		= sizeof(int),
6371 		.mode		= 0644,
6372 		.proc_handler	= proc_dointvec,
6373 	},
6374 	{
6375 		.procname	= "accept_ra_pinfo",
6376 		.data		= &ipv6_devconf.accept_ra_pinfo,
6377 		.maxlen		= sizeof(int),
6378 		.mode		= 0644,
6379 		.proc_handler	= proc_dointvec,
6380 	},
6381 #ifdef CONFIG_IPV6_ROUTER_PREF
6382 	{
6383 		.procname	= "accept_ra_rtr_pref",
6384 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6385 		.maxlen		= sizeof(int),
6386 		.mode		= 0644,
6387 		.proc_handler	= proc_dointvec,
6388 	},
6389 	{
6390 		.procname	= "router_probe_interval",
6391 		.data		= &ipv6_devconf.rtr_probe_interval,
6392 		.maxlen		= sizeof(int),
6393 		.mode		= 0644,
6394 		.proc_handler	= proc_dointvec_jiffies,
6395 	},
6396 #ifdef CONFIG_IPV6_ROUTE_INFO
6397 	{
6398 		.procname	= "accept_ra_rt_info_min_plen",
6399 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6400 		.maxlen		= sizeof(int),
6401 		.mode		= 0644,
6402 		.proc_handler	= proc_dointvec,
6403 	},
6404 	{
6405 		.procname	= "accept_ra_rt_info_max_plen",
6406 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6407 		.maxlen		= sizeof(int),
6408 		.mode		= 0644,
6409 		.proc_handler	= proc_dointvec,
6410 	},
6411 #endif
6412 #endif
6413 	{
6414 		.procname	= "proxy_ndp",
6415 		.data		= &ipv6_devconf.proxy_ndp,
6416 		.maxlen		= sizeof(int),
6417 		.mode		= 0644,
6418 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6419 	},
6420 	{
6421 		.procname	= "accept_source_route",
6422 		.data		= &ipv6_devconf.accept_source_route,
6423 		.maxlen		= sizeof(int),
6424 		.mode		= 0644,
6425 		.proc_handler	= proc_dointvec,
6426 	},
6427 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
6428 	{
6429 		.procname	= "optimistic_dad",
6430 		.data		= &ipv6_devconf.optimistic_dad,
6431 		.maxlen		= sizeof(int),
6432 		.mode		= 0644,
6433 		.proc_handler   = proc_dointvec,
6434 	},
6435 	{
6436 		.procname	= "use_optimistic",
6437 		.data		= &ipv6_devconf.use_optimistic,
6438 		.maxlen		= sizeof(int),
6439 		.mode		= 0644,
6440 		.proc_handler	= proc_dointvec,
6441 	},
6442 #endif
6443 #ifdef CONFIG_IPV6_MROUTE
6444 	{
6445 		.procname	= "mc_forwarding",
6446 		.data		= &ipv6_devconf.mc_forwarding,
6447 		.maxlen		= sizeof(int),
6448 		.mode		= 0444,
6449 		.proc_handler	= proc_dointvec,
6450 	},
6451 #endif
6452 	{
6453 		.procname	= "disable_ipv6",
6454 		.data		= &ipv6_devconf.disable_ipv6,
6455 		.maxlen		= sizeof(int),
6456 		.mode		= 0644,
6457 		.proc_handler	= addrconf_sysctl_disable,
6458 	},
6459 	{
6460 		.procname	= "accept_dad",
6461 		.data		= &ipv6_devconf.accept_dad,
6462 		.maxlen		= sizeof(int),
6463 		.mode		= 0644,
6464 		.proc_handler	= proc_dointvec,
6465 	},
6466 	{
6467 		.procname	= "force_tllao",
6468 		.data		= &ipv6_devconf.force_tllao,
6469 		.maxlen		= sizeof(int),
6470 		.mode		= 0644,
6471 		.proc_handler	= proc_dointvec
6472 	},
6473 	{
6474 		.procname	= "ndisc_notify",
6475 		.data		= &ipv6_devconf.ndisc_notify,
6476 		.maxlen		= sizeof(int),
6477 		.mode		= 0644,
6478 		.proc_handler	= proc_dointvec
6479 	},
6480 	{
6481 		.procname	= "suppress_frag_ndisc",
6482 		.data		= &ipv6_devconf.suppress_frag_ndisc,
6483 		.maxlen		= sizeof(int),
6484 		.mode		= 0644,
6485 		.proc_handler	= proc_dointvec
6486 	},
6487 	{
6488 		.procname	= "accept_ra_from_local",
6489 		.data		= &ipv6_devconf.accept_ra_from_local,
6490 		.maxlen		= sizeof(int),
6491 		.mode		= 0644,
6492 		.proc_handler	= proc_dointvec,
6493 	},
6494 	{
6495 		.procname	= "accept_ra_mtu",
6496 		.data		= &ipv6_devconf.accept_ra_mtu,
6497 		.maxlen		= sizeof(int),
6498 		.mode		= 0644,
6499 		.proc_handler	= proc_dointvec,
6500 	},
6501 	{
6502 		.procname	= "stable_secret",
6503 		.data		= &ipv6_devconf.stable_secret,
6504 		.maxlen		= IPV6_MAX_STRLEN,
6505 		.mode		= 0600,
6506 		.proc_handler	= addrconf_sysctl_stable_secret,
6507 	},
6508 	{
6509 		.procname	= "use_oif_addrs_only",
6510 		.data		= &ipv6_devconf.use_oif_addrs_only,
6511 		.maxlen		= sizeof(int),
6512 		.mode		= 0644,
6513 		.proc_handler	= proc_dointvec,
6514 	},
6515 	{
6516 		.procname	= "ignore_routes_with_linkdown",
6517 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
6518 		.maxlen		= sizeof(int),
6519 		.mode		= 0644,
6520 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
6521 	},
6522 	{
6523 		.procname	= "drop_unicast_in_l2_multicast",
6524 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
6525 		.maxlen		= sizeof(int),
6526 		.mode		= 0644,
6527 		.proc_handler	= proc_dointvec,
6528 	},
6529 	{
6530 		.procname	= "drop_unsolicited_na",
6531 		.data		= &ipv6_devconf.drop_unsolicited_na,
6532 		.maxlen		= sizeof(int),
6533 		.mode		= 0644,
6534 		.proc_handler	= proc_dointvec,
6535 	},
6536 	{
6537 		.procname	= "keep_addr_on_down",
6538 		.data		= &ipv6_devconf.keep_addr_on_down,
6539 		.maxlen		= sizeof(int),
6540 		.mode		= 0644,
6541 		.proc_handler	= proc_dointvec,
6542 
6543 	},
6544 	{
6545 		.procname	= "seg6_enabled",
6546 		.data		= &ipv6_devconf.seg6_enabled,
6547 		.maxlen		= sizeof(int),
6548 		.mode		= 0644,
6549 		.proc_handler	= proc_dointvec,
6550 	},
6551 #ifdef CONFIG_IPV6_SEG6_HMAC
6552 	{
6553 		.procname	= "seg6_require_hmac",
6554 		.data		= &ipv6_devconf.seg6_require_hmac,
6555 		.maxlen		= sizeof(int),
6556 		.mode		= 0644,
6557 		.proc_handler	= proc_dointvec,
6558 	},
6559 #endif
6560 	{
6561 		.procname       = "enhanced_dad",
6562 		.data           = &ipv6_devconf.enhanced_dad,
6563 		.maxlen         = sizeof(int),
6564 		.mode           = 0644,
6565 		.proc_handler   = proc_dointvec,
6566 	},
6567 	{
6568 		.procname		= "addr_gen_mode",
6569 		.data			= &ipv6_devconf.addr_gen_mode,
6570 		.maxlen			= sizeof(int),
6571 		.mode			= 0644,
6572 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
6573 	},
6574 	{
6575 		.procname       = "disable_policy",
6576 		.data           = &ipv6_devconf.disable_policy,
6577 		.maxlen         = sizeof(int),
6578 		.mode           = 0644,
6579 		.proc_handler   = addrconf_sysctl_disable_policy,
6580 	},
6581 	{
6582 		.procname	= "ndisc_tclass",
6583 		.data		= &ipv6_devconf.ndisc_tclass,
6584 		.maxlen		= sizeof(int),
6585 		.mode		= 0644,
6586 		.proc_handler	= proc_dointvec_minmax,
6587 		.extra1		= (void *)&zero,
6588 		.extra2		= (void *)&two_five_five,
6589 	},
6590 	{
6591 		/* sentinel */
6592 	}
6593 };
6594 
6595 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
6596 		struct inet6_dev *idev, struct ipv6_devconf *p)
6597 {
6598 	int i, ifindex;
6599 	struct ctl_table *table;
6600 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
6601 
6602 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL);
6603 	if (!table)
6604 		goto out;
6605 
6606 	for (i = 0; table[i].data; i++) {
6607 		table[i].data += (char *)p - (char *)&ipv6_devconf;
6608 		/* If one of these is already set, then it is not safe to
6609 		 * overwrite either of them: this makes proc_dointvec_minmax
6610 		 * usable.
6611 		 */
6612 		if (!table[i].extra1 && !table[i].extra2) {
6613 			table[i].extra1 = idev; /* embedded; no ref */
6614 			table[i].extra2 = net;
6615 		}
6616 	}
6617 
6618 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
6619 
6620 	p->sysctl_header = register_net_sysctl(net, path, table);
6621 	if (!p->sysctl_header)
6622 		goto free;
6623 
6624 	if (!strcmp(dev_name, "all"))
6625 		ifindex = NETCONFA_IFINDEX_ALL;
6626 	else if (!strcmp(dev_name, "default"))
6627 		ifindex = NETCONFA_IFINDEX_DEFAULT;
6628 	else
6629 		ifindex = idev->dev->ifindex;
6630 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
6631 				     ifindex, p);
6632 	return 0;
6633 
6634 free:
6635 	kfree(table);
6636 out:
6637 	return -ENOBUFS;
6638 }
6639 
6640 static void __addrconf_sysctl_unregister(struct net *net,
6641 					 struct ipv6_devconf *p, int ifindex)
6642 {
6643 	struct ctl_table *table;
6644 
6645 	if (!p->sysctl_header)
6646 		return;
6647 
6648 	table = p->sysctl_header->ctl_table_arg;
6649 	unregister_net_sysctl_table(p->sysctl_header);
6650 	p->sysctl_header = NULL;
6651 	kfree(table);
6652 
6653 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
6654 }
6655 
6656 static int addrconf_sysctl_register(struct inet6_dev *idev)
6657 {
6658 	int err;
6659 
6660 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
6661 		return -EINVAL;
6662 
6663 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
6664 				    &ndisc_ifinfo_sysctl_change);
6665 	if (err)
6666 		return err;
6667 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
6668 					 idev, &idev->cnf);
6669 	if (err)
6670 		neigh_sysctl_unregister(idev->nd_parms);
6671 
6672 	return err;
6673 }
6674 
6675 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
6676 {
6677 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
6678 				     idev->dev->ifindex);
6679 	neigh_sysctl_unregister(idev->nd_parms);
6680 }
6681 
6682 
6683 #endif
6684 
6685 static int __net_init addrconf_init_net(struct net *net)
6686 {
6687 	int err = -ENOMEM;
6688 	struct ipv6_devconf *all, *dflt;
6689 
6690 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
6691 	if (!all)
6692 		goto err_alloc_all;
6693 
6694 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
6695 	if (!dflt)
6696 		goto err_alloc_dflt;
6697 
6698 	/* these will be inherited by all namespaces */
6699 	dflt->autoconf = ipv6_defaults.autoconf;
6700 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
6701 
6702 	dflt->stable_secret.initialized = false;
6703 	all->stable_secret.initialized = false;
6704 
6705 	net->ipv6.devconf_all = all;
6706 	net->ipv6.devconf_dflt = dflt;
6707 
6708 #ifdef CONFIG_SYSCTL
6709 	err = __addrconf_sysctl_register(net, "all", NULL, all);
6710 	if (err < 0)
6711 		goto err_reg_all;
6712 
6713 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
6714 	if (err < 0)
6715 		goto err_reg_dflt;
6716 #endif
6717 	return 0;
6718 
6719 #ifdef CONFIG_SYSCTL
6720 err_reg_dflt:
6721 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
6722 err_reg_all:
6723 	kfree(dflt);
6724 #endif
6725 err_alloc_dflt:
6726 	kfree(all);
6727 err_alloc_all:
6728 	return err;
6729 }
6730 
6731 static void __net_exit addrconf_exit_net(struct net *net)
6732 {
6733 #ifdef CONFIG_SYSCTL
6734 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
6735 				     NETCONFA_IFINDEX_DEFAULT);
6736 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
6737 				     NETCONFA_IFINDEX_ALL);
6738 #endif
6739 	kfree(net->ipv6.devconf_dflt);
6740 	kfree(net->ipv6.devconf_all);
6741 }
6742 
6743 static struct pernet_operations addrconf_ops = {
6744 	.init = addrconf_init_net,
6745 	.exit = addrconf_exit_net,
6746 };
6747 
6748 static struct rtnl_af_ops inet6_ops __read_mostly = {
6749 	.family		  = AF_INET6,
6750 	.fill_link_af	  = inet6_fill_link_af,
6751 	.get_link_af_size = inet6_get_link_af_size,
6752 	.validate_link_af = inet6_validate_link_af,
6753 	.set_link_af	  = inet6_set_link_af,
6754 };
6755 
6756 /*
6757  *	Init / cleanup code
6758  */
6759 
6760 int __init addrconf_init(void)
6761 {
6762 	struct inet6_dev *idev;
6763 	int i, err;
6764 
6765 	err = ipv6_addr_label_init();
6766 	if (err < 0) {
6767 		pr_crit("%s: cannot initialize default policy table: %d\n",
6768 			__func__, err);
6769 		goto out;
6770 	}
6771 
6772 	err = register_pernet_subsys(&addrconf_ops);
6773 	if (err < 0)
6774 		goto out_addrlabel;
6775 
6776 	addrconf_wq = create_workqueue("ipv6_addrconf");
6777 	if (!addrconf_wq) {
6778 		err = -ENOMEM;
6779 		goto out_nowq;
6780 	}
6781 
6782 	/* The addrconf netdev notifier requires that loopback_dev
6783 	 * has it's ipv6 private information allocated and setup
6784 	 * before it can bring up and give link-local addresses
6785 	 * to other devices which are up.
6786 	 *
6787 	 * Unfortunately, loopback_dev is not necessarily the first
6788 	 * entry in the global dev_base list of net devices.  In fact,
6789 	 * it is likely to be the very last entry on that list.
6790 	 * So this causes the notifier registry below to try and
6791 	 * give link-local addresses to all devices besides loopback_dev
6792 	 * first, then loopback_dev, which cases all the non-loopback_dev
6793 	 * devices to fail to get a link-local address.
6794 	 *
6795 	 * So, as a temporary fix, allocate the ipv6 structure for
6796 	 * loopback_dev first by hand.
6797 	 * Longer term, all of the dependencies ipv6 has upon the loopback
6798 	 * device and it being up should be removed.
6799 	 */
6800 	rtnl_lock();
6801 	idev = ipv6_add_dev(init_net.loopback_dev);
6802 	rtnl_unlock();
6803 	if (IS_ERR(idev)) {
6804 		err = PTR_ERR(idev);
6805 		goto errlo;
6806 	}
6807 
6808 	ip6_route_init_special_entries();
6809 
6810 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
6811 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
6812 
6813 	register_netdevice_notifier(&ipv6_dev_notf);
6814 
6815 	addrconf_verify();
6816 
6817 	rtnl_af_register(&inet6_ops);
6818 
6819 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETLINK,
6820 				   NULL, inet6_dump_ifinfo, 0);
6821 	if (err < 0)
6822 		goto errout;
6823 
6824 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWADDR,
6825 				   inet6_rtm_newaddr, NULL, 0);
6826 	if (err < 0)
6827 		goto errout;
6828 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELADDR,
6829 				   inet6_rtm_deladdr, NULL, 0);
6830 	if (err < 0)
6831 		goto errout;
6832 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDR,
6833 				   inet6_rtm_getaddr, inet6_dump_ifaddr,
6834 				   RTNL_FLAG_DOIT_UNLOCKED);
6835 	if (err < 0)
6836 		goto errout;
6837 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETMULTICAST,
6838 				   NULL, inet6_dump_ifmcaddr, 0);
6839 	if (err < 0)
6840 		goto errout;
6841 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETANYCAST,
6842 				   NULL, inet6_dump_ifacaddr, 0);
6843 	if (err < 0)
6844 		goto errout;
6845 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETNETCONF,
6846 				   inet6_netconf_get_devconf,
6847 				   inet6_netconf_dump_devconf,
6848 				   RTNL_FLAG_DOIT_UNLOCKED);
6849 	if (err < 0)
6850 		goto errout;
6851 	err = ipv6_addr_label_rtnl_register();
6852 	if (err < 0)
6853 		goto errout;
6854 
6855 	return 0;
6856 errout:
6857 	rtnl_unregister_all(PF_INET6);
6858 	rtnl_af_unregister(&inet6_ops);
6859 	unregister_netdevice_notifier(&ipv6_dev_notf);
6860 errlo:
6861 	destroy_workqueue(addrconf_wq);
6862 out_nowq:
6863 	unregister_pernet_subsys(&addrconf_ops);
6864 out_addrlabel:
6865 	ipv6_addr_label_cleanup();
6866 out:
6867 	return err;
6868 }
6869 
6870 void addrconf_cleanup(void)
6871 {
6872 	struct net_device *dev;
6873 	int i;
6874 
6875 	unregister_netdevice_notifier(&ipv6_dev_notf);
6876 	unregister_pernet_subsys(&addrconf_ops);
6877 	ipv6_addr_label_cleanup();
6878 
6879 	rtnl_af_unregister(&inet6_ops);
6880 
6881 	rtnl_lock();
6882 
6883 	/* clean dev list */
6884 	for_each_netdev(&init_net, dev) {
6885 		if (__in6_dev_get(dev) == NULL)
6886 			continue;
6887 		addrconf_ifdown(dev, 1);
6888 	}
6889 	addrconf_ifdown(init_net.loopback_dev, 2);
6890 
6891 	/*
6892 	 *	Check hash table.
6893 	 */
6894 	spin_lock_bh(&addrconf_hash_lock);
6895 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
6896 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
6897 	spin_unlock_bh(&addrconf_hash_lock);
6898 	cancel_delayed_work(&addr_chk_work);
6899 	rtnl_unlock();
6900 
6901 	destroy_workqueue(addrconf_wq);
6902 }
6903