xref: /linux/net/ipv6/addrconf.c (revision abe11ddea1d759f9995a9a4636c28c9b40856ca8)
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/socket.h>
47 #include <linux/sockios.h>
48 #include <linux/net.h>
49 #include <linux/in6.h>
50 #include <linux/netdevice.h>
51 #include <linux/if_addr.h>
52 #include <linux/if_arp.h>
53 #include <linux/if_arcnet.h>
54 #include <linux/if_infiniband.h>
55 #include <linux/route.h>
56 #include <linux/inetdevice.h>
57 #include <linux/init.h>
58 #include <linux/slab.h>
59 #ifdef CONFIG_SYSCTL
60 #include <linux/sysctl.h>
61 #endif
62 #include <linux/capability.h>
63 #include <linux/delay.h>
64 #include <linux/notifier.h>
65 #include <linux/string.h>
66 #include <linux/hash.h>
67 
68 #include <net/net_namespace.h>
69 #include <net/sock.h>
70 #include <net/snmp.h>
71 
72 #include <net/af_ieee802154.h>
73 #include <net/ipv6.h>
74 #include <net/protocol.h>
75 #include <net/ndisc.h>
76 #include <net/ip6_route.h>
77 #include <net/addrconf.h>
78 #include <net/tcp.h>
79 #include <net/ip.h>
80 #include <net/netlink.h>
81 #include <net/pkt_sched.h>
82 #include <linux/if_tunnel.h>
83 #include <linux/rtnetlink.h>
84 #include <linux/netconf.h>
85 
86 #ifdef CONFIG_IPV6_PRIVACY
87 #include <linux/random.h>
88 #endif
89 
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 /* Set to 3 to get tracing... */
98 #define ACONF_DEBUG 2
99 
100 #if ACONF_DEBUG >= 3
101 #define ADBG(x) printk x
102 #else
103 #define ADBG(x)
104 #endif
105 
106 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
107 
108 static inline u32 cstamp_delta(unsigned long cstamp)
109 {
110 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
111 }
112 
113 #define ADDRCONF_TIMER_FUZZ_MINUS	(HZ > 50 ? HZ/50 : 1)
114 #define ADDRCONF_TIMER_FUZZ		(HZ / 4)
115 #define ADDRCONF_TIMER_FUZZ_MAX		(HZ)
116 
117 #ifdef CONFIG_SYSCTL
118 static void addrconf_sysctl_register(struct inet6_dev *idev);
119 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
120 #else
121 static inline void addrconf_sysctl_register(struct inet6_dev *idev)
122 {
123 }
124 
125 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
126 {
127 }
128 #endif
129 
130 #ifdef CONFIG_IPV6_PRIVACY
131 static void __ipv6_regen_rndid(struct inet6_dev *idev);
132 static void __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
133 static void ipv6_regen_rndid(unsigned long data);
134 #endif
135 
136 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
137 static int ipv6_count_addresses(struct inet6_dev *idev);
138 
139 /*
140  *	Configured unicast address hash table
141  */
142 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
143 static DEFINE_SPINLOCK(addrconf_hash_lock);
144 
145 static void addrconf_verify(unsigned long);
146 
147 static DEFINE_TIMER(addr_chk_timer, addrconf_verify, 0, 0);
148 static DEFINE_SPINLOCK(addrconf_verify_lock);
149 
150 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
151 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
152 
153 static void addrconf_type_change(struct net_device *dev,
154 				 unsigned long event);
155 static int addrconf_ifdown(struct net_device *dev, int how);
156 
157 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
158 						  int plen,
159 						  const struct net_device *dev,
160 						  u32 flags, u32 noflags);
161 
162 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
163 static void addrconf_dad_timer(unsigned long data);
164 static void addrconf_dad_completed(struct inet6_ifaddr *ifp);
165 static void addrconf_dad_run(struct inet6_dev *idev);
166 static void addrconf_rs_timer(unsigned long data);
167 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
168 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
169 
170 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
171 				struct prefix_info *pinfo);
172 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
173 			       struct net_device *dev);
174 
175 static ATOMIC_NOTIFIER_HEAD(inet6addr_chain);
176 
177 static struct ipv6_devconf ipv6_devconf __read_mostly = {
178 	.forwarding		= 0,
179 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
180 	.mtu6			= IPV6_MIN_MTU,
181 	.accept_ra		= 1,
182 	.accept_redirects	= 1,
183 	.autoconf		= 1,
184 	.force_mld_version	= 0,
185 	.dad_transmits		= 1,
186 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
187 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
188 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
189 #ifdef CONFIG_IPV6_PRIVACY
190 	.use_tempaddr 		= 0,
191 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
192 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
193 	.regen_max_retry	= REGEN_MAX_RETRY,
194 	.max_desync_factor	= MAX_DESYNC_FACTOR,
195 #endif
196 	.max_addresses		= IPV6_MAX_ADDRESSES,
197 	.accept_ra_defrtr	= 1,
198 	.accept_ra_pinfo	= 1,
199 #ifdef CONFIG_IPV6_ROUTER_PREF
200 	.accept_ra_rtr_pref	= 1,
201 	.rtr_probe_interval	= 60 * HZ,
202 #ifdef CONFIG_IPV6_ROUTE_INFO
203 	.accept_ra_rt_info_max_plen = 0,
204 #endif
205 #endif
206 	.proxy_ndp		= 0,
207 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
208 	.disable_ipv6		= 0,
209 	.accept_dad		= 1,
210 };
211 
212 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
213 	.forwarding		= 0,
214 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
215 	.mtu6			= IPV6_MIN_MTU,
216 	.accept_ra		= 1,
217 	.accept_redirects	= 1,
218 	.autoconf		= 1,
219 	.dad_transmits		= 1,
220 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
221 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
222 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
223 #ifdef CONFIG_IPV6_PRIVACY
224 	.use_tempaddr		= 0,
225 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
226 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
227 	.regen_max_retry	= REGEN_MAX_RETRY,
228 	.max_desync_factor	= MAX_DESYNC_FACTOR,
229 #endif
230 	.max_addresses		= IPV6_MAX_ADDRESSES,
231 	.accept_ra_defrtr	= 1,
232 	.accept_ra_pinfo	= 1,
233 #ifdef CONFIG_IPV6_ROUTER_PREF
234 	.accept_ra_rtr_pref	= 1,
235 	.rtr_probe_interval	= 60 * HZ,
236 #ifdef CONFIG_IPV6_ROUTE_INFO
237 	.accept_ra_rt_info_max_plen = 0,
238 #endif
239 #endif
240 	.proxy_ndp		= 0,
241 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
242 	.disable_ipv6		= 0,
243 	.accept_dad		= 1,
244 };
245 
246 /* IPv6 Wildcard Address and Loopback Address defined by RFC2553 */
247 const struct in6_addr in6addr_any = IN6ADDR_ANY_INIT;
248 const struct in6_addr in6addr_loopback = IN6ADDR_LOOPBACK_INIT;
249 const struct in6_addr in6addr_linklocal_allnodes = IN6ADDR_LINKLOCAL_ALLNODES_INIT;
250 const struct in6_addr in6addr_linklocal_allrouters = IN6ADDR_LINKLOCAL_ALLROUTERS_INIT;
251 
252 /* Check if a valid qdisc is available */
253 static inline bool addrconf_qdisc_ok(const struct net_device *dev)
254 {
255 	return !qdisc_tx_is_noop(dev);
256 }
257 
258 static void addrconf_del_timer(struct inet6_ifaddr *ifp)
259 {
260 	if (del_timer(&ifp->timer))
261 		__in6_ifa_put(ifp);
262 }
263 
264 enum addrconf_timer_t {
265 	AC_NONE,
266 	AC_DAD,
267 	AC_RS,
268 };
269 
270 static void addrconf_mod_timer(struct inet6_ifaddr *ifp,
271 			       enum addrconf_timer_t what,
272 			       unsigned long when)
273 {
274 	if (!del_timer(&ifp->timer))
275 		in6_ifa_hold(ifp);
276 
277 	switch (what) {
278 	case AC_DAD:
279 		ifp->timer.function = addrconf_dad_timer;
280 		break;
281 	case AC_RS:
282 		ifp->timer.function = addrconf_rs_timer;
283 		break;
284 	default:
285 		break;
286 	}
287 	ifp->timer.expires = jiffies + when;
288 	add_timer(&ifp->timer);
289 }
290 
291 static int snmp6_alloc_dev(struct inet6_dev *idev)
292 {
293 	if (snmp_mib_init((void __percpu **)idev->stats.ipv6,
294 			  sizeof(struct ipstats_mib),
295 			  __alignof__(struct ipstats_mib)) < 0)
296 		goto err_ip;
297 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
298 					GFP_KERNEL);
299 	if (!idev->stats.icmpv6dev)
300 		goto err_icmp;
301 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
302 					   GFP_KERNEL);
303 	if (!idev->stats.icmpv6msgdev)
304 		goto err_icmpmsg;
305 
306 	return 0;
307 
308 err_icmpmsg:
309 	kfree(idev->stats.icmpv6dev);
310 err_icmp:
311 	snmp_mib_free((void __percpu **)idev->stats.ipv6);
312 err_ip:
313 	return -ENOMEM;
314 }
315 
316 static void snmp6_free_dev(struct inet6_dev *idev)
317 {
318 	kfree(idev->stats.icmpv6msgdev);
319 	kfree(idev->stats.icmpv6dev);
320 	snmp_mib_free((void __percpu **)idev->stats.ipv6);
321 }
322 
323 /* Nobody refers to this device, we may destroy it. */
324 
325 void in6_dev_finish_destroy(struct inet6_dev *idev)
326 {
327 	struct net_device *dev = idev->dev;
328 
329 	WARN_ON(!list_empty(&idev->addr_list));
330 	WARN_ON(idev->mc_list != NULL);
331 
332 #ifdef NET_REFCNT_DEBUG
333 	pr_debug("%s: %s\n", __func__, dev ? dev->name : "NIL");
334 #endif
335 	dev_put(dev);
336 	if (!idev->dead) {
337 		pr_warn("Freeing alive inet6 device %p\n", idev);
338 		return;
339 	}
340 	snmp6_free_dev(idev);
341 	kfree_rcu(idev, rcu);
342 }
343 EXPORT_SYMBOL(in6_dev_finish_destroy);
344 
345 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
346 {
347 	struct inet6_dev *ndev;
348 
349 	ASSERT_RTNL();
350 
351 	if (dev->mtu < IPV6_MIN_MTU)
352 		return NULL;
353 
354 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
355 
356 	if (ndev == NULL)
357 		return NULL;
358 
359 	rwlock_init(&ndev->lock);
360 	ndev->dev = dev;
361 	INIT_LIST_HEAD(&ndev->addr_list);
362 
363 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
364 	ndev->cnf.mtu6 = dev->mtu;
365 	ndev->cnf.sysctl = NULL;
366 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
367 	if (ndev->nd_parms == NULL) {
368 		kfree(ndev);
369 		return NULL;
370 	}
371 	if (ndev->cnf.forwarding)
372 		dev_disable_lro(dev);
373 	/* We refer to the device */
374 	dev_hold(dev);
375 
376 	if (snmp6_alloc_dev(ndev) < 0) {
377 		ADBG((KERN_WARNING
378 			"%s: cannot allocate memory for statistics; dev=%s.\n",
379 			__func__, dev->name));
380 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
381 		dev_put(dev);
382 		kfree(ndev);
383 		return NULL;
384 	}
385 
386 	if (snmp6_register_dev(ndev) < 0) {
387 		ADBG((KERN_WARNING
388 			"%s: cannot create /proc/net/dev_snmp6/%s\n",
389 			__func__, dev->name));
390 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
391 		ndev->dead = 1;
392 		in6_dev_finish_destroy(ndev);
393 		return NULL;
394 	}
395 
396 	/* One reference from device.  We must do this before
397 	 * we invoke __ipv6_regen_rndid().
398 	 */
399 	in6_dev_hold(ndev);
400 
401 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
402 		ndev->cnf.accept_dad = -1;
403 
404 #if IS_ENABLED(CONFIG_IPV6_SIT)
405 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
406 		pr_info("%s: Disabled Multicast RS\n", dev->name);
407 		ndev->cnf.rtr_solicits = 0;
408 	}
409 #endif
410 
411 #ifdef CONFIG_IPV6_PRIVACY
412 	INIT_LIST_HEAD(&ndev->tempaddr_list);
413 	setup_timer(&ndev->regen_timer, ipv6_regen_rndid, (unsigned long)ndev);
414 	if ((dev->flags&IFF_LOOPBACK) ||
415 	    dev->type == ARPHRD_TUNNEL ||
416 	    dev->type == ARPHRD_TUNNEL6 ||
417 	    dev->type == ARPHRD_SIT ||
418 	    dev->type == ARPHRD_NONE) {
419 		ndev->cnf.use_tempaddr = -1;
420 	} else {
421 		in6_dev_hold(ndev);
422 		ipv6_regen_rndid((unsigned long) ndev);
423 	}
424 #endif
425 
426 	if (netif_running(dev) && addrconf_qdisc_ok(dev))
427 		ndev->if_flags |= IF_READY;
428 
429 	ipv6_mc_init_dev(ndev);
430 	ndev->tstamp = jiffies;
431 	addrconf_sysctl_register(ndev);
432 	/* protected by rtnl_lock */
433 	rcu_assign_pointer(dev->ip6_ptr, ndev);
434 
435 	/* Join all-node multicast group */
436 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
437 
438 	/* Join all-router multicast group if forwarding is set */
439 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
440 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
441 
442 	return ndev;
443 }
444 
445 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
446 {
447 	struct inet6_dev *idev;
448 
449 	ASSERT_RTNL();
450 
451 	idev = __in6_dev_get(dev);
452 	if (!idev) {
453 		idev = ipv6_add_dev(dev);
454 		if (!idev)
455 			return NULL;
456 	}
457 
458 	if (dev->flags&IFF_UP)
459 		ipv6_mc_up(idev);
460 	return idev;
461 }
462 
463 static int inet6_netconf_msgsize_devconf(int type)
464 {
465 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
466 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
467 
468 	/* type -1 is used for ALL */
469 	if (type == -1 || type == NETCONFA_FORWARDING)
470 		size += nla_total_size(4);
471 #ifdef CONFIG_IPV6_MROUTE
472 	if (type == -1 || type == NETCONFA_MC_FORWARDING)
473 		size += nla_total_size(4);
474 #endif
475 
476 	return size;
477 }
478 
479 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
480 				      struct ipv6_devconf *devconf, u32 portid,
481 				      u32 seq, int event, unsigned int flags,
482 				      int type)
483 {
484 	struct nlmsghdr  *nlh;
485 	struct netconfmsg *ncm;
486 
487 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
488 			flags);
489 	if (nlh == NULL)
490 		return -EMSGSIZE;
491 
492 	ncm = nlmsg_data(nlh);
493 	ncm->ncm_family = AF_INET6;
494 
495 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
496 		goto nla_put_failure;
497 
498 	/* type -1 is used for ALL */
499 	if ((type == -1 || type == NETCONFA_FORWARDING) &&
500 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
501 		goto nla_put_failure;
502 #ifdef CONFIG_IPV6_MROUTE
503 	if ((type == -1 || type == NETCONFA_MC_FORWARDING) &&
504 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
505 			devconf->mc_forwarding) < 0)
506 		goto nla_put_failure;
507 #endif
508 	return nlmsg_end(skb, nlh);
509 
510 nla_put_failure:
511 	nlmsg_cancel(skb, nlh);
512 	return -EMSGSIZE;
513 }
514 
515 void inet6_netconf_notify_devconf(struct net *net, int type, int ifindex,
516 				  struct ipv6_devconf *devconf)
517 {
518 	struct sk_buff *skb;
519 	int err = -ENOBUFS;
520 
521 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_ATOMIC);
522 	if (skb == NULL)
523 		goto errout;
524 
525 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
526 					 RTM_NEWNETCONF, 0, type);
527 	if (err < 0) {
528 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
529 		WARN_ON(err == -EMSGSIZE);
530 		kfree_skb(skb);
531 		goto errout;
532 	}
533 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_ATOMIC);
534 	return;
535 errout:
536 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
537 }
538 
539 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
540 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
541 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
542 };
543 
544 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
545 				     struct nlmsghdr *nlh,
546 				     void *arg)
547 {
548 	struct net *net = sock_net(in_skb->sk);
549 	struct nlattr *tb[NETCONFA_MAX+1];
550 	struct netconfmsg *ncm;
551 	struct sk_buff *skb;
552 	struct ipv6_devconf *devconf;
553 	struct inet6_dev *in6_dev;
554 	struct net_device *dev;
555 	int ifindex;
556 	int err;
557 
558 	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
559 			  devconf_ipv6_policy);
560 	if (err < 0)
561 		goto errout;
562 
563 	err = EINVAL;
564 	if (!tb[NETCONFA_IFINDEX])
565 		goto errout;
566 
567 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
568 	switch (ifindex) {
569 	case NETCONFA_IFINDEX_ALL:
570 		devconf = net->ipv6.devconf_all;
571 		break;
572 	case NETCONFA_IFINDEX_DEFAULT:
573 		devconf = net->ipv6.devconf_dflt;
574 		break;
575 	default:
576 		dev = __dev_get_by_index(net, ifindex);
577 		if (dev == NULL)
578 			goto errout;
579 		in6_dev = __in6_dev_get(dev);
580 		if (in6_dev == NULL)
581 			goto errout;
582 		devconf = &in6_dev->cnf;
583 		break;
584 	}
585 
586 	err = -ENOBUFS;
587 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(-1), GFP_ATOMIC);
588 	if (skb == NULL)
589 		goto errout;
590 
591 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
592 					 NETLINK_CB(in_skb).portid,
593 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
594 					 -1);
595 	if (err < 0) {
596 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
597 		WARN_ON(err == -EMSGSIZE);
598 		kfree_skb(skb);
599 		goto errout;
600 	}
601 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
602 errout:
603 	return err;
604 }
605 
606 #ifdef CONFIG_SYSCTL
607 static void dev_forward_change(struct inet6_dev *idev)
608 {
609 	struct net_device *dev;
610 	struct inet6_ifaddr *ifa;
611 
612 	if (!idev)
613 		return;
614 	dev = idev->dev;
615 	if (idev->cnf.forwarding)
616 		dev_disable_lro(dev);
617 	if (dev->flags & IFF_MULTICAST) {
618 		if (idev->cnf.forwarding)
619 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
620 		else
621 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
622 	}
623 
624 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
625 		if (ifa->flags&IFA_F_TENTATIVE)
626 			continue;
627 		if (idev->cnf.forwarding)
628 			addrconf_join_anycast(ifa);
629 		else
630 			addrconf_leave_anycast(ifa);
631 	}
632 	inet6_netconf_notify_devconf(dev_net(dev), NETCONFA_FORWARDING,
633 				     dev->ifindex, &idev->cnf);
634 }
635 
636 
637 static void addrconf_forward_change(struct net *net, __s32 newf)
638 {
639 	struct net_device *dev;
640 	struct inet6_dev *idev;
641 
642 	for_each_netdev(net, dev) {
643 		idev = __in6_dev_get(dev);
644 		if (idev) {
645 			int changed = (!idev->cnf.forwarding) ^ (!newf);
646 			idev->cnf.forwarding = newf;
647 			if (changed)
648 				dev_forward_change(idev);
649 		}
650 	}
651 }
652 
653 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
654 {
655 	struct net *net;
656 	int old;
657 
658 	if (!rtnl_trylock())
659 		return restart_syscall();
660 
661 	net = (struct net *)table->extra2;
662 	old = *p;
663 	*p = newf;
664 
665 	if (p == &net->ipv6.devconf_dflt->forwarding) {
666 		if ((!newf) ^ (!old))
667 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
668 						     NETCONFA_IFINDEX_DEFAULT,
669 						     net->ipv6.devconf_dflt);
670 		rtnl_unlock();
671 		return 0;
672 	}
673 
674 	if (p == &net->ipv6.devconf_all->forwarding) {
675 		net->ipv6.devconf_dflt->forwarding = newf;
676 		addrconf_forward_change(net, newf);
677 		if ((!newf) ^ (!old))
678 			inet6_netconf_notify_devconf(net, NETCONFA_FORWARDING,
679 						     NETCONFA_IFINDEX_ALL,
680 						     net->ipv6.devconf_all);
681 	} else if ((!newf) ^ (!old))
682 		dev_forward_change((struct inet6_dev *)table->extra1);
683 	rtnl_unlock();
684 
685 	if (newf)
686 		rt6_purge_dflt_routers(net);
687 	return 1;
688 }
689 #endif
690 
691 /* Nobody refers to this ifaddr, destroy it */
692 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
693 {
694 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
695 
696 #ifdef NET_REFCNT_DEBUG
697 	pr_debug("%s\n", __func__);
698 #endif
699 
700 	in6_dev_put(ifp->idev);
701 
702 	if (del_timer(&ifp->timer))
703 		pr_notice("Timer is still running, when freeing ifa=%p\n", ifp);
704 
705 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
706 		pr_warn("Freeing alive inet6 address %p\n", ifp);
707 		return;
708 	}
709 	ip6_rt_put(ifp->rt);
710 
711 	kfree_rcu(ifp, rcu);
712 }
713 
714 static void
715 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
716 {
717 	struct list_head *p;
718 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
719 
720 	/*
721 	 * Each device address list is sorted in order of scope -
722 	 * global before linklocal.
723 	 */
724 	list_for_each(p, &idev->addr_list) {
725 		struct inet6_ifaddr *ifa
726 			= list_entry(p, struct inet6_ifaddr, if_list);
727 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
728 			break;
729 	}
730 
731 	list_add_tail(&ifp->if_list, p);
732 }
733 
734 static u32 inet6_addr_hash(const struct in6_addr *addr)
735 {
736 	return hash_32(ipv6_addr_hash(addr), IN6_ADDR_HSIZE_SHIFT);
737 }
738 
739 /* On success it returns ifp with increased reference count */
740 
741 static struct inet6_ifaddr *
742 ipv6_add_addr(struct inet6_dev *idev, const struct in6_addr *addr, int pfxlen,
743 	      int scope, u32 flags)
744 {
745 	struct inet6_ifaddr *ifa = NULL;
746 	struct rt6_info *rt;
747 	unsigned int hash;
748 	int err = 0;
749 	int addr_type = ipv6_addr_type(addr);
750 
751 	if (addr_type == IPV6_ADDR_ANY ||
752 	    addr_type & IPV6_ADDR_MULTICAST ||
753 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
754 	     addr_type & IPV6_ADDR_LOOPBACK))
755 		return ERR_PTR(-EADDRNOTAVAIL);
756 
757 	rcu_read_lock_bh();
758 	if (idev->dead) {
759 		err = -ENODEV;			/*XXX*/
760 		goto out2;
761 	}
762 
763 	if (idev->cnf.disable_ipv6) {
764 		err = -EACCES;
765 		goto out2;
766 	}
767 
768 	spin_lock(&addrconf_hash_lock);
769 
770 	/* Ignore adding duplicate addresses on an interface */
771 	if (ipv6_chk_same_addr(dev_net(idev->dev), addr, idev->dev)) {
772 		ADBG(("ipv6_add_addr: already assigned\n"));
773 		err = -EEXIST;
774 		goto out;
775 	}
776 
777 	ifa = kzalloc(sizeof(struct inet6_ifaddr), GFP_ATOMIC);
778 
779 	if (ifa == NULL) {
780 		ADBG(("ipv6_add_addr: malloc failed\n"));
781 		err = -ENOBUFS;
782 		goto out;
783 	}
784 
785 	rt = addrconf_dst_alloc(idev, addr, false);
786 	if (IS_ERR(rt)) {
787 		err = PTR_ERR(rt);
788 		goto out;
789 	}
790 
791 	ifa->addr = *addr;
792 
793 	spin_lock_init(&ifa->lock);
794 	spin_lock_init(&ifa->state_lock);
795 	init_timer(&ifa->timer);
796 	INIT_HLIST_NODE(&ifa->addr_lst);
797 	ifa->timer.data = (unsigned long) ifa;
798 	ifa->scope = scope;
799 	ifa->prefix_len = pfxlen;
800 	ifa->flags = flags | IFA_F_TENTATIVE;
801 	ifa->cstamp = ifa->tstamp = jiffies;
802 
803 	ifa->rt = rt;
804 
805 	ifa->idev = idev;
806 	in6_dev_hold(idev);
807 	/* For caller */
808 	in6_ifa_hold(ifa);
809 
810 	/* Add to big hash table */
811 	hash = inet6_addr_hash(addr);
812 
813 	hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
814 	spin_unlock(&addrconf_hash_lock);
815 
816 	write_lock(&idev->lock);
817 	/* Add to inet6_dev unicast addr list. */
818 	ipv6_link_dev_addr(idev, ifa);
819 
820 #ifdef CONFIG_IPV6_PRIVACY
821 	if (ifa->flags&IFA_F_TEMPORARY) {
822 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
823 		in6_ifa_hold(ifa);
824 	}
825 #endif
826 
827 	in6_ifa_hold(ifa);
828 	write_unlock(&idev->lock);
829 out2:
830 	rcu_read_unlock_bh();
831 
832 	if (likely(err == 0))
833 		atomic_notifier_call_chain(&inet6addr_chain, NETDEV_UP, ifa);
834 	else {
835 		kfree(ifa);
836 		ifa = ERR_PTR(err);
837 	}
838 
839 	return ifa;
840 out:
841 	spin_unlock(&addrconf_hash_lock);
842 	goto out2;
843 }
844 
845 /* This function wants to get referenced ifp and releases it before return */
846 
847 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
848 {
849 	struct inet6_ifaddr *ifa, *ifn;
850 	struct inet6_dev *idev = ifp->idev;
851 	int state;
852 	int deleted = 0, onlink = 0;
853 	unsigned long expires = jiffies;
854 
855 	spin_lock_bh(&ifp->state_lock);
856 	state = ifp->state;
857 	ifp->state = INET6_IFADDR_STATE_DEAD;
858 	spin_unlock_bh(&ifp->state_lock);
859 
860 	if (state == INET6_IFADDR_STATE_DEAD)
861 		goto out;
862 
863 	spin_lock_bh(&addrconf_hash_lock);
864 	hlist_del_init_rcu(&ifp->addr_lst);
865 	spin_unlock_bh(&addrconf_hash_lock);
866 
867 	write_lock_bh(&idev->lock);
868 #ifdef CONFIG_IPV6_PRIVACY
869 	if (ifp->flags&IFA_F_TEMPORARY) {
870 		list_del(&ifp->tmp_list);
871 		if (ifp->ifpub) {
872 			in6_ifa_put(ifp->ifpub);
873 			ifp->ifpub = NULL;
874 		}
875 		__in6_ifa_put(ifp);
876 	}
877 #endif
878 
879 	list_for_each_entry_safe(ifa, ifn, &idev->addr_list, if_list) {
880 		if (ifa == ifp) {
881 			list_del_init(&ifp->if_list);
882 			__in6_ifa_put(ifp);
883 
884 			if (!(ifp->flags & IFA_F_PERMANENT) || onlink > 0)
885 				break;
886 			deleted = 1;
887 			continue;
888 		} else if (ifp->flags & IFA_F_PERMANENT) {
889 			if (ipv6_prefix_equal(&ifa->addr, &ifp->addr,
890 					      ifp->prefix_len)) {
891 				if (ifa->flags & IFA_F_PERMANENT) {
892 					onlink = 1;
893 					if (deleted)
894 						break;
895 				} else {
896 					unsigned long lifetime;
897 
898 					if (!onlink)
899 						onlink = -1;
900 
901 					spin_lock(&ifa->lock);
902 
903 					lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
904 					/*
905 					 * Note: Because this address is
906 					 * not permanent, lifetime <
907 					 * LONG_MAX / HZ here.
908 					 */
909 					if (time_before(expires,
910 							ifa->tstamp + lifetime * HZ))
911 						expires = ifa->tstamp + lifetime * HZ;
912 					spin_unlock(&ifa->lock);
913 				}
914 			}
915 		}
916 	}
917 	write_unlock_bh(&idev->lock);
918 
919 	addrconf_del_timer(ifp);
920 
921 	ipv6_ifa_notify(RTM_DELADDR, ifp);
922 
923 	atomic_notifier_call_chain(&inet6addr_chain, NETDEV_DOWN, ifp);
924 
925 	/*
926 	 * Purge or update corresponding prefix
927 	 *
928 	 * 1) we don't purge prefix here if address was not permanent.
929 	 *    prefix is managed by its own lifetime.
930 	 * 2) if there're no addresses, delete prefix.
931 	 * 3) if there're still other permanent address(es),
932 	 *    corresponding prefix is still permanent.
933 	 * 4) otherwise, update prefix lifetime to the
934 	 *    longest valid lifetime among the corresponding
935 	 *    addresses on the device.
936 	 *    Note: subsequent RA will update lifetime.
937 	 *
938 	 * --yoshfuji
939 	 */
940 	if ((ifp->flags & IFA_F_PERMANENT) && onlink < 1) {
941 		struct in6_addr prefix;
942 		struct rt6_info *rt;
943 
944 		ipv6_addr_prefix(&prefix, &ifp->addr, ifp->prefix_len);
945 
946 		rt = addrconf_get_prefix_route(&prefix,
947 					       ifp->prefix_len,
948 					       ifp->idev->dev,
949 					       0, RTF_GATEWAY | RTF_DEFAULT);
950 
951 		if (rt) {
952 			if (onlink == 0) {
953 				ip6_del_rt(rt);
954 				rt = NULL;
955 			} else if (!(rt->rt6i_flags & RTF_EXPIRES)) {
956 				rt6_set_expires(rt, expires);
957 			}
958 		}
959 		ip6_rt_put(rt);
960 	}
961 
962 	/* clean up prefsrc entries */
963 	rt6_remove_prefsrc(ifp);
964 out:
965 	in6_ifa_put(ifp);
966 }
967 
968 #ifdef CONFIG_IPV6_PRIVACY
969 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, struct inet6_ifaddr *ift)
970 {
971 	struct inet6_dev *idev = ifp->idev;
972 	struct in6_addr addr, *tmpaddr;
973 	unsigned long tmp_prefered_lft, tmp_valid_lft, tmp_tstamp, age;
974 	unsigned long regen_advance;
975 	int tmp_plen;
976 	int ret = 0;
977 	int max_addresses;
978 	u32 addr_flags;
979 	unsigned long now = jiffies;
980 
981 	write_lock(&idev->lock);
982 	if (ift) {
983 		spin_lock_bh(&ift->lock);
984 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
985 		spin_unlock_bh(&ift->lock);
986 		tmpaddr = &addr;
987 	} else {
988 		tmpaddr = NULL;
989 	}
990 retry:
991 	in6_dev_hold(idev);
992 	if (idev->cnf.use_tempaddr <= 0) {
993 		write_unlock(&idev->lock);
994 		pr_info("%s: use_tempaddr is disabled\n", __func__);
995 		in6_dev_put(idev);
996 		ret = -1;
997 		goto out;
998 	}
999 	spin_lock_bh(&ifp->lock);
1000 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1001 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1002 		spin_unlock_bh(&ifp->lock);
1003 		write_unlock(&idev->lock);
1004 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1005 			__func__);
1006 		in6_dev_put(idev);
1007 		ret = -1;
1008 		goto out;
1009 	}
1010 	in6_ifa_hold(ifp);
1011 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1012 	__ipv6_try_regen_rndid(idev, tmpaddr);
1013 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1014 	age = (now - ifp->tstamp) / HZ;
1015 	tmp_valid_lft = min_t(__u32,
1016 			      ifp->valid_lft,
1017 			      idev->cnf.temp_valid_lft + age);
1018 	tmp_prefered_lft = min_t(__u32,
1019 				 ifp->prefered_lft,
1020 				 idev->cnf.temp_prefered_lft + age -
1021 				 idev->cnf.max_desync_factor);
1022 	tmp_plen = ifp->prefix_len;
1023 	max_addresses = idev->cnf.max_addresses;
1024 	tmp_tstamp = ifp->tstamp;
1025 	spin_unlock_bh(&ifp->lock);
1026 
1027 	regen_advance = idev->cnf.regen_max_retry *
1028 	                idev->cnf.dad_transmits *
1029 	                idev->nd_parms->retrans_time / HZ;
1030 	write_unlock(&idev->lock);
1031 
1032 	/* A temporary address is created only if this calculated Preferred
1033 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1034 	 * an implementation must not create a temporary address with a zero
1035 	 * Preferred Lifetime.
1036 	 */
1037 	if (tmp_prefered_lft <= regen_advance) {
1038 		in6_ifa_put(ifp);
1039 		in6_dev_put(idev);
1040 		ret = -1;
1041 		goto out;
1042 	}
1043 
1044 	addr_flags = IFA_F_TEMPORARY;
1045 	/* set in addrconf_prefix_rcv() */
1046 	if (ifp->flags & IFA_F_OPTIMISTIC)
1047 		addr_flags |= IFA_F_OPTIMISTIC;
1048 
1049 	ift = !max_addresses ||
1050 	      ipv6_count_addresses(idev) < max_addresses ?
1051 		ipv6_add_addr(idev, &addr, tmp_plen,
1052 			      ipv6_addr_type(&addr)&IPV6_ADDR_SCOPE_MASK,
1053 			      addr_flags) : NULL;
1054 	if (!ift || IS_ERR(ift)) {
1055 		in6_ifa_put(ifp);
1056 		in6_dev_put(idev);
1057 		pr_info("%s: retry temporary address regeneration\n", __func__);
1058 		tmpaddr = &addr;
1059 		write_lock(&idev->lock);
1060 		goto retry;
1061 	}
1062 
1063 	spin_lock_bh(&ift->lock);
1064 	ift->ifpub = ifp;
1065 	ift->valid_lft = tmp_valid_lft;
1066 	ift->prefered_lft = tmp_prefered_lft;
1067 	ift->cstamp = now;
1068 	ift->tstamp = tmp_tstamp;
1069 	spin_unlock_bh(&ift->lock);
1070 
1071 	addrconf_dad_start(ift);
1072 	in6_ifa_put(ift);
1073 	in6_dev_put(idev);
1074 out:
1075 	return ret;
1076 }
1077 #endif
1078 
1079 /*
1080  *	Choose an appropriate source address (RFC3484)
1081  */
1082 enum {
1083 	IPV6_SADDR_RULE_INIT = 0,
1084 	IPV6_SADDR_RULE_LOCAL,
1085 	IPV6_SADDR_RULE_SCOPE,
1086 	IPV6_SADDR_RULE_PREFERRED,
1087 #ifdef CONFIG_IPV6_MIP6
1088 	IPV6_SADDR_RULE_HOA,
1089 #endif
1090 	IPV6_SADDR_RULE_OIF,
1091 	IPV6_SADDR_RULE_LABEL,
1092 #ifdef CONFIG_IPV6_PRIVACY
1093 	IPV6_SADDR_RULE_PRIVACY,
1094 #endif
1095 	IPV6_SADDR_RULE_ORCHID,
1096 	IPV6_SADDR_RULE_PREFIX,
1097 	IPV6_SADDR_RULE_MAX
1098 };
1099 
1100 struct ipv6_saddr_score {
1101 	int			rule;
1102 	int			addr_type;
1103 	struct inet6_ifaddr	*ifa;
1104 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1105 	int			scopedist;
1106 	int			matchlen;
1107 };
1108 
1109 struct ipv6_saddr_dst {
1110 	const struct in6_addr *addr;
1111 	int ifindex;
1112 	int scope;
1113 	int label;
1114 	unsigned int prefs;
1115 };
1116 
1117 static inline int ipv6_saddr_preferred(int type)
1118 {
1119 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1120 		return 1;
1121 	return 0;
1122 }
1123 
1124 static int ipv6_get_saddr_eval(struct net *net,
1125 			       struct ipv6_saddr_score *score,
1126 			       struct ipv6_saddr_dst *dst,
1127 			       int i)
1128 {
1129 	int ret;
1130 
1131 	if (i <= score->rule) {
1132 		switch (i) {
1133 		case IPV6_SADDR_RULE_SCOPE:
1134 			ret = score->scopedist;
1135 			break;
1136 		case IPV6_SADDR_RULE_PREFIX:
1137 			ret = score->matchlen;
1138 			break;
1139 		default:
1140 			ret = !!test_bit(i, score->scorebits);
1141 		}
1142 		goto out;
1143 	}
1144 
1145 	switch (i) {
1146 	case IPV6_SADDR_RULE_INIT:
1147 		/* Rule 0: remember if hiscore is not ready yet */
1148 		ret = !!score->ifa;
1149 		break;
1150 	case IPV6_SADDR_RULE_LOCAL:
1151 		/* Rule 1: Prefer same address */
1152 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1153 		break;
1154 	case IPV6_SADDR_RULE_SCOPE:
1155 		/* Rule 2: Prefer appropriate scope
1156 		 *
1157 		 *      ret
1158 		 *       ^
1159 		 *    -1 |  d 15
1160 		 *    ---+--+-+---> scope
1161 		 *       |
1162 		 *       |             d is scope of the destination.
1163 		 *  B-d  |  \
1164 		 *       |   \      <- smaller scope is better if
1165 		 *  B-15 |    \        if scope is enough for destinaion.
1166 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1167 		 * d-C-1 | /
1168 		 *       |/         <- greater is better
1169 		 *   -C  /             if scope is not enough for destination.
1170 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1171 		 *
1172 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1173 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1174 		 * Assume B = 0 and we get C > 29.
1175 		 */
1176 		ret = __ipv6_addr_src_scope(score->addr_type);
1177 		if (ret >= dst->scope)
1178 			ret = -ret;
1179 		else
1180 			ret -= 128;	/* 30 is enough */
1181 		score->scopedist = ret;
1182 		break;
1183 	case IPV6_SADDR_RULE_PREFERRED:
1184 		/* Rule 3: Avoid deprecated and optimistic addresses */
1185 		ret = ipv6_saddr_preferred(score->addr_type) ||
1186 		      !(score->ifa->flags & (IFA_F_DEPRECATED|IFA_F_OPTIMISTIC));
1187 		break;
1188 #ifdef CONFIG_IPV6_MIP6
1189 	case IPV6_SADDR_RULE_HOA:
1190 	    {
1191 		/* Rule 4: Prefer home address */
1192 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1193 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1194 		break;
1195 	    }
1196 #endif
1197 	case IPV6_SADDR_RULE_OIF:
1198 		/* Rule 5: Prefer outgoing interface */
1199 		ret = (!dst->ifindex ||
1200 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1201 		break;
1202 	case IPV6_SADDR_RULE_LABEL:
1203 		/* Rule 6: Prefer matching label */
1204 		ret = ipv6_addr_label(net,
1205 				      &score->ifa->addr, score->addr_type,
1206 				      score->ifa->idev->dev->ifindex) == dst->label;
1207 		break;
1208 #ifdef CONFIG_IPV6_PRIVACY
1209 	case IPV6_SADDR_RULE_PRIVACY:
1210 	    {
1211 		/* Rule 7: Prefer public address
1212 		 * Note: prefer temporary address if use_tempaddr >= 2
1213 		 */
1214 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1215 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1216 				score->ifa->idev->cnf.use_tempaddr >= 2;
1217 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1218 		break;
1219 	    }
1220 #endif
1221 	case IPV6_SADDR_RULE_ORCHID:
1222 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1223 		 *	    non-ORCHID vs non-ORCHID
1224 		 */
1225 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1226 			ipv6_addr_orchid(dst->addr));
1227 		break;
1228 	case IPV6_SADDR_RULE_PREFIX:
1229 		/* Rule 8: Use longest matching prefix */
1230 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1231 		if (ret > score->ifa->prefix_len)
1232 			ret = score->ifa->prefix_len;
1233 		score->matchlen = ret;
1234 		break;
1235 	default:
1236 		ret = 0;
1237 	}
1238 
1239 	if (ret)
1240 		__set_bit(i, score->scorebits);
1241 	score->rule = i;
1242 out:
1243 	return ret;
1244 }
1245 
1246 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1247 		       const struct in6_addr *daddr, unsigned int prefs,
1248 		       struct in6_addr *saddr)
1249 {
1250 	struct ipv6_saddr_score scores[2],
1251 				*score = &scores[0], *hiscore = &scores[1];
1252 	struct ipv6_saddr_dst dst;
1253 	struct net_device *dev;
1254 	int dst_type;
1255 
1256 	dst_type = __ipv6_addr_type(daddr);
1257 	dst.addr = daddr;
1258 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1259 	dst.scope = __ipv6_addr_src_scope(dst_type);
1260 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1261 	dst.prefs = prefs;
1262 
1263 	hiscore->rule = -1;
1264 	hiscore->ifa = NULL;
1265 
1266 	rcu_read_lock();
1267 
1268 	for_each_netdev_rcu(net, dev) {
1269 		struct inet6_dev *idev;
1270 
1271 		/* Candidate Source Address (section 4)
1272 		 *  - multicast and link-local destination address,
1273 		 *    the set of candidate source address MUST only
1274 		 *    include addresses assigned to interfaces
1275 		 *    belonging to the same link as the outgoing
1276 		 *    interface.
1277 		 * (- For site-local destination addresses, the
1278 		 *    set of candidate source addresses MUST only
1279 		 *    include addresses assigned to interfaces
1280 		 *    belonging to the same site as the outgoing
1281 		 *    interface.)
1282 		 */
1283 		if (((dst_type & IPV6_ADDR_MULTICAST) ||
1284 		     dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL) &&
1285 		    dst.ifindex && dev->ifindex != dst.ifindex)
1286 			continue;
1287 
1288 		idev = __in6_dev_get(dev);
1289 		if (!idev)
1290 			continue;
1291 
1292 		read_lock_bh(&idev->lock);
1293 		list_for_each_entry(score->ifa, &idev->addr_list, if_list) {
1294 			int i;
1295 
1296 			/*
1297 			 * - Tentative Address (RFC2462 section 5.4)
1298 			 *  - A tentative address is not considered
1299 			 *    "assigned to an interface" in the traditional
1300 			 *    sense, unless it is also flagged as optimistic.
1301 			 * - Candidate Source Address (section 4)
1302 			 *  - In any case, anycast addresses, multicast
1303 			 *    addresses, and the unspecified address MUST
1304 			 *    NOT be included in a candidate set.
1305 			 */
1306 			if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1307 			    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1308 				continue;
1309 
1310 			score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1311 
1312 			if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1313 				     score->addr_type & IPV6_ADDR_MULTICAST)) {
1314 				LIMIT_NETDEBUG(KERN_DEBUG
1315 					       "ADDRCONF: unspecified / multicast address "
1316 					       "assigned as unicast address on %s",
1317 					       dev->name);
1318 				continue;
1319 			}
1320 
1321 			score->rule = -1;
1322 			bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1323 
1324 			for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1325 				int minihiscore, miniscore;
1326 
1327 				minihiscore = ipv6_get_saddr_eval(net, hiscore, &dst, i);
1328 				miniscore = ipv6_get_saddr_eval(net, score, &dst, i);
1329 
1330 				if (minihiscore > miniscore) {
1331 					if (i == IPV6_SADDR_RULE_SCOPE &&
1332 					    score->scopedist > 0) {
1333 						/*
1334 						 * special case:
1335 						 * each remaining entry
1336 						 * has too small (not enough)
1337 						 * scope, because ifa entries
1338 						 * are sorted by their scope
1339 						 * values.
1340 						 */
1341 						goto try_nextdev;
1342 					}
1343 					break;
1344 				} else if (minihiscore < miniscore) {
1345 					if (hiscore->ifa)
1346 						in6_ifa_put(hiscore->ifa);
1347 
1348 					in6_ifa_hold(score->ifa);
1349 
1350 					swap(hiscore, score);
1351 
1352 					/* restore our iterator */
1353 					score->ifa = hiscore->ifa;
1354 
1355 					break;
1356 				}
1357 			}
1358 		}
1359 try_nextdev:
1360 		read_unlock_bh(&idev->lock);
1361 	}
1362 	rcu_read_unlock();
1363 
1364 	if (!hiscore->ifa)
1365 		return -EADDRNOTAVAIL;
1366 
1367 	*saddr = hiscore->ifa->addr;
1368 	in6_ifa_put(hiscore->ifa);
1369 	return 0;
1370 }
1371 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1372 
1373 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1374 		    unsigned char banned_flags)
1375 {
1376 	struct inet6_dev *idev;
1377 	int err = -EADDRNOTAVAIL;
1378 
1379 	rcu_read_lock();
1380 	idev = __in6_dev_get(dev);
1381 	if (idev) {
1382 		struct inet6_ifaddr *ifp;
1383 
1384 		read_lock_bh(&idev->lock);
1385 		list_for_each_entry(ifp, &idev->addr_list, if_list) {
1386 			if (ifp->scope == IFA_LINK &&
1387 			    !(ifp->flags & banned_flags)) {
1388 				*addr = ifp->addr;
1389 				err = 0;
1390 				break;
1391 			}
1392 		}
1393 		read_unlock_bh(&idev->lock);
1394 	}
1395 	rcu_read_unlock();
1396 	return err;
1397 }
1398 
1399 static int ipv6_count_addresses(struct inet6_dev *idev)
1400 {
1401 	int cnt = 0;
1402 	struct inet6_ifaddr *ifp;
1403 
1404 	read_lock_bh(&idev->lock);
1405 	list_for_each_entry(ifp, &idev->addr_list, if_list)
1406 		cnt++;
1407 	read_unlock_bh(&idev->lock);
1408 	return cnt;
1409 }
1410 
1411 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1412 		  struct net_device *dev, int strict)
1413 {
1414 	struct inet6_ifaddr *ifp;
1415 	struct hlist_node *node;
1416 	unsigned int hash = inet6_addr_hash(addr);
1417 
1418 	rcu_read_lock_bh();
1419 	hlist_for_each_entry_rcu(ifp, node, &inet6_addr_lst[hash], addr_lst) {
1420 		if (!net_eq(dev_net(ifp->idev->dev), net))
1421 			continue;
1422 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1423 		    !(ifp->flags&IFA_F_TENTATIVE) &&
1424 		    (dev == NULL || ifp->idev->dev == dev ||
1425 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1426 			rcu_read_unlock_bh();
1427 			return 1;
1428 		}
1429 	}
1430 
1431 	rcu_read_unlock_bh();
1432 	return 0;
1433 }
1434 EXPORT_SYMBOL(ipv6_chk_addr);
1435 
1436 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1437 			       struct net_device *dev)
1438 {
1439 	unsigned int hash = inet6_addr_hash(addr);
1440 	struct inet6_ifaddr *ifp;
1441 	struct hlist_node *node;
1442 
1443 	hlist_for_each_entry(ifp, node, &inet6_addr_lst[hash], addr_lst) {
1444 		if (!net_eq(dev_net(ifp->idev->dev), net))
1445 			continue;
1446 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1447 			if (dev == NULL || ifp->idev->dev == dev)
1448 				return true;
1449 		}
1450 	}
1451 	return false;
1452 }
1453 
1454 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1455 {
1456 	struct inet6_dev *idev;
1457 	struct inet6_ifaddr *ifa;
1458 	int	onlink;
1459 
1460 	onlink = 0;
1461 	rcu_read_lock();
1462 	idev = __in6_dev_get(dev);
1463 	if (idev) {
1464 		read_lock_bh(&idev->lock);
1465 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
1466 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1467 						   ifa->prefix_len);
1468 			if (onlink)
1469 				break;
1470 		}
1471 		read_unlock_bh(&idev->lock);
1472 	}
1473 	rcu_read_unlock();
1474 	return onlink;
1475 }
1476 EXPORT_SYMBOL(ipv6_chk_prefix);
1477 
1478 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1479 				     struct net_device *dev, int strict)
1480 {
1481 	struct inet6_ifaddr *ifp, *result = NULL;
1482 	unsigned int hash = inet6_addr_hash(addr);
1483 	struct hlist_node *node;
1484 
1485 	rcu_read_lock_bh();
1486 	hlist_for_each_entry_rcu_bh(ifp, node, &inet6_addr_lst[hash], addr_lst) {
1487 		if (!net_eq(dev_net(ifp->idev->dev), net))
1488 			continue;
1489 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1490 			if (dev == NULL || ifp->idev->dev == dev ||
1491 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
1492 				result = ifp;
1493 				in6_ifa_hold(ifp);
1494 				break;
1495 			}
1496 		}
1497 	}
1498 	rcu_read_unlock_bh();
1499 
1500 	return result;
1501 }
1502 
1503 /* Gets referenced address, destroys ifaddr */
1504 
1505 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
1506 {
1507 	if (ifp->flags&IFA_F_PERMANENT) {
1508 		spin_lock_bh(&ifp->lock);
1509 		addrconf_del_timer(ifp);
1510 		ifp->flags |= IFA_F_TENTATIVE;
1511 		if (dad_failed)
1512 			ifp->flags |= IFA_F_DADFAILED;
1513 		spin_unlock_bh(&ifp->lock);
1514 		if (dad_failed)
1515 			ipv6_ifa_notify(0, ifp);
1516 		in6_ifa_put(ifp);
1517 #ifdef CONFIG_IPV6_PRIVACY
1518 	} else if (ifp->flags&IFA_F_TEMPORARY) {
1519 		struct inet6_ifaddr *ifpub;
1520 		spin_lock_bh(&ifp->lock);
1521 		ifpub = ifp->ifpub;
1522 		if (ifpub) {
1523 			in6_ifa_hold(ifpub);
1524 			spin_unlock_bh(&ifp->lock);
1525 			ipv6_create_tempaddr(ifpub, ifp);
1526 			in6_ifa_put(ifpub);
1527 		} else {
1528 			spin_unlock_bh(&ifp->lock);
1529 		}
1530 		ipv6_del_addr(ifp);
1531 #endif
1532 	} else
1533 		ipv6_del_addr(ifp);
1534 }
1535 
1536 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
1537 {
1538 	int err = -ENOENT;
1539 
1540 	spin_lock(&ifp->state_lock);
1541 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
1542 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
1543 		err = 0;
1544 	}
1545 	spin_unlock(&ifp->state_lock);
1546 
1547 	return err;
1548 }
1549 
1550 void addrconf_dad_failure(struct inet6_ifaddr *ifp)
1551 {
1552 	struct inet6_dev *idev = ifp->idev;
1553 
1554 	if (addrconf_dad_end(ifp)) {
1555 		in6_ifa_put(ifp);
1556 		return;
1557 	}
1558 
1559 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c detected!\n",
1560 			     ifp->idev->dev->name, &ifp->addr);
1561 
1562 	if (idev->cnf.accept_dad > 1 && !idev->cnf.disable_ipv6) {
1563 		struct in6_addr addr;
1564 
1565 		addr.s6_addr32[0] = htonl(0xfe800000);
1566 		addr.s6_addr32[1] = 0;
1567 
1568 		if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
1569 		    ipv6_addr_equal(&ifp->addr, &addr)) {
1570 			/* DAD failed for link-local based on MAC address */
1571 			idev->cnf.disable_ipv6 = 1;
1572 
1573 			pr_info("%s: IPv6 being disabled!\n",
1574 				ifp->idev->dev->name);
1575 		}
1576 	}
1577 
1578 	addrconf_dad_stop(ifp, 1);
1579 }
1580 
1581 /* Join to solicited addr multicast group. */
1582 
1583 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
1584 {
1585 	struct in6_addr maddr;
1586 
1587 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1588 		return;
1589 
1590 	addrconf_addr_solict_mult(addr, &maddr);
1591 	ipv6_dev_mc_inc(dev, &maddr);
1592 }
1593 
1594 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
1595 {
1596 	struct in6_addr maddr;
1597 
1598 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
1599 		return;
1600 
1601 	addrconf_addr_solict_mult(addr, &maddr);
1602 	__ipv6_dev_mc_dec(idev, &maddr);
1603 }
1604 
1605 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
1606 {
1607 	struct in6_addr addr;
1608 	if (ifp->prefix_len == 127) /* RFC 6164 */
1609 		return;
1610 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1611 	if (ipv6_addr_any(&addr))
1612 		return;
1613 	ipv6_dev_ac_inc(ifp->idev->dev, &addr);
1614 }
1615 
1616 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
1617 {
1618 	struct in6_addr addr;
1619 	if (ifp->prefix_len == 127) /* RFC 6164 */
1620 		return;
1621 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
1622 	if (ipv6_addr_any(&addr))
1623 		return;
1624 	__ipv6_dev_ac_dec(ifp->idev, &addr);
1625 }
1626 
1627 static int addrconf_ifid_eui48(u8 *eui, struct net_device *dev)
1628 {
1629 	if (dev->addr_len != ETH_ALEN)
1630 		return -1;
1631 	memcpy(eui, dev->dev_addr, 3);
1632 	memcpy(eui + 5, dev->dev_addr + 3, 3);
1633 
1634 	/*
1635 	 * The zSeries OSA network cards can be shared among various
1636 	 * OS instances, but the OSA cards have only one MAC address.
1637 	 * This leads to duplicate address conflicts in conjunction
1638 	 * with IPv6 if more than one instance uses the same card.
1639 	 *
1640 	 * The driver for these cards can deliver a unique 16-bit
1641 	 * identifier for each instance sharing the same card.  It is
1642 	 * placed instead of 0xFFFE in the interface identifier.  The
1643 	 * "u" bit of the interface identifier is not inverted in this
1644 	 * case.  Hence the resulting interface identifier has local
1645 	 * scope according to RFC2373.
1646 	 */
1647 	if (dev->dev_id) {
1648 		eui[3] = (dev->dev_id >> 8) & 0xFF;
1649 		eui[4] = dev->dev_id & 0xFF;
1650 	} else {
1651 		eui[3] = 0xFF;
1652 		eui[4] = 0xFE;
1653 		eui[0] ^= 2;
1654 	}
1655 	return 0;
1656 }
1657 
1658 static int addrconf_ifid_eui64(u8 *eui, struct net_device *dev)
1659 {
1660 	if (dev->addr_len != IEEE802154_ADDR_LEN)
1661 		return -1;
1662 	memcpy(eui, dev->dev_addr, 8);
1663 	return 0;
1664 }
1665 
1666 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
1667 {
1668 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
1669 	if (dev->addr_len != ARCNET_ALEN)
1670 		return -1;
1671 	memset(eui, 0, 7);
1672 	eui[7] = *(u8 *)dev->dev_addr;
1673 	return 0;
1674 }
1675 
1676 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
1677 {
1678 	if (dev->addr_len != INFINIBAND_ALEN)
1679 		return -1;
1680 	memcpy(eui, dev->dev_addr + 12, 8);
1681 	eui[0] |= 2;
1682 	return 0;
1683 }
1684 
1685 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
1686 {
1687 	if (addr == 0)
1688 		return -1;
1689 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
1690 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
1691 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
1692 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
1693 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
1694 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
1695 	eui[1] = 0;
1696 	eui[2] = 0x5E;
1697 	eui[3] = 0xFE;
1698 	memcpy(eui + 4, &addr, 4);
1699 	return 0;
1700 }
1701 
1702 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
1703 {
1704 	if (dev->priv_flags & IFF_ISATAP)
1705 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1706 	return -1;
1707 }
1708 
1709 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
1710 {
1711 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
1712 }
1713 
1714 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
1715 {
1716 	switch (dev->type) {
1717 	case ARPHRD_ETHER:
1718 	case ARPHRD_FDDI:
1719 		return addrconf_ifid_eui48(eui, dev);
1720 	case ARPHRD_ARCNET:
1721 		return addrconf_ifid_arcnet(eui, dev);
1722 	case ARPHRD_INFINIBAND:
1723 		return addrconf_ifid_infiniband(eui, dev);
1724 	case ARPHRD_SIT:
1725 		return addrconf_ifid_sit(eui, dev);
1726 	case ARPHRD_IPGRE:
1727 		return addrconf_ifid_gre(eui, dev);
1728 	case ARPHRD_IEEE802154:
1729 		return addrconf_ifid_eui64(eui, dev);
1730 	}
1731 	return -1;
1732 }
1733 
1734 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
1735 {
1736 	int err = -1;
1737 	struct inet6_ifaddr *ifp;
1738 
1739 	read_lock_bh(&idev->lock);
1740 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
1741 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
1742 			memcpy(eui, ifp->addr.s6_addr+8, 8);
1743 			err = 0;
1744 			break;
1745 		}
1746 	}
1747 	read_unlock_bh(&idev->lock);
1748 	return err;
1749 }
1750 
1751 #ifdef CONFIG_IPV6_PRIVACY
1752 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
1753 static void __ipv6_regen_rndid(struct inet6_dev *idev)
1754 {
1755 regen:
1756 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
1757 	idev->rndid[0] &= ~0x02;
1758 
1759 	/*
1760 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
1761 	 * check if generated address is not inappropriate
1762 	 *
1763 	 *  - Reserved subnet anycast (RFC 2526)
1764 	 *	11111101 11....11 1xxxxxxx
1765 	 *  - ISATAP (RFC4214) 6.1
1766 	 *	00-00-5E-FE-xx-xx-xx-xx
1767 	 *  - value 0
1768 	 *  - XXX: already assigned to an address on the device
1769 	 */
1770 	if (idev->rndid[0] == 0xfd &&
1771 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
1772 	    (idev->rndid[7]&0x80))
1773 		goto regen;
1774 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
1775 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
1776 			goto regen;
1777 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
1778 			goto regen;
1779 	}
1780 }
1781 
1782 static void ipv6_regen_rndid(unsigned long data)
1783 {
1784 	struct inet6_dev *idev = (struct inet6_dev *) data;
1785 	unsigned long expires;
1786 
1787 	rcu_read_lock_bh();
1788 	write_lock_bh(&idev->lock);
1789 
1790 	if (idev->dead)
1791 		goto out;
1792 
1793 	__ipv6_regen_rndid(idev);
1794 
1795 	expires = jiffies +
1796 		idev->cnf.temp_prefered_lft * HZ -
1797 		idev->cnf.regen_max_retry * idev->cnf.dad_transmits * idev->nd_parms->retrans_time -
1798 		idev->cnf.max_desync_factor * HZ;
1799 	if (time_before(expires, jiffies)) {
1800 		pr_warn("%s: too short regeneration interval; timer disabled for %s\n",
1801 			__func__, idev->dev->name);
1802 		goto out;
1803 	}
1804 
1805 	if (!mod_timer(&idev->regen_timer, expires))
1806 		in6_dev_hold(idev);
1807 
1808 out:
1809 	write_unlock_bh(&idev->lock);
1810 	rcu_read_unlock_bh();
1811 	in6_dev_put(idev);
1812 }
1813 
1814 static void  __ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
1815 {
1816 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
1817 		__ipv6_regen_rndid(idev);
1818 }
1819 #endif
1820 
1821 /*
1822  *	Add prefix route.
1823  */
1824 
1825 static void
1826 addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev,
1827 		      unsigned long expires, u32 flags)
1828 {
1829 	struct fib6_config cfg = {
1830 		.fc_table = RT6_TABLE_PREFIX,
1831 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
1832 		.fc_ifindex = dev->ifindex,
1833 		.fc_expires = expires,
1834 		.fc_dst_len = plen,
1835 		.fc_flags = RTF_UP | flags,
1836 		.fc_nlinfo.nl_net = dev_net(dev),
1837 		.fc_protocol = RTPROT_KERNEL,
1838 	};
1839 
1840 	cfg.fc_dst = *pfx;
1841 
1842 	/* Prevent useless cloning on PtP SIT.
1843 	   This thing is done here expecting that the whole
1844 	   class of non-broadcast devices need not cloning.
1845 	 */
1846 #if IS_ENABLED(CONFIG_IPV6_SIT)
1847 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
1848 		cfg.fc_flags |= RTF_NONEXTHOP;
1849 #endif
1850 
1851 	ip6_route_add(&cfg);
1852 }
1853 
1854 
1855 static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
1856 						  int plen,
1857 						  const struct net_device *dev,
1858 						  u32 flags, u32 noflags)
1859 {
1860 	struct fib6_node *fn;
1861 	struct rt6_info *rt = NULL;
1862 	struct fib6_table *table;
1863 
1864 	table = fib6_get_table(dev_net(dev), RT6_TABLE_PREFIX);
1865 	if (table == NULL)
1866 		return NULL;
1867 
1868 	read_lock_bh(&table->tb6_lock);
1869 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0);
1870 	if (!fn)
1871 		goto out;
1872 	for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) {
1873 		if (rt->dst.dev->ifindex != dev->ifindex)
1874 			continue;
1875 		if ((rt->rt6i_flags & flags) != flags)
1876 			continue;
1877 		if ((rt->rt6i_flags & noflags) != 0)
1878 			continue;
1879 		dst_hold(&rt->dst);
1880 		break;
1881 	}
1882 out:
1883 	read_unlock_bh(&table->tb6_lock);
1884 	return rt;
1885 }
1886 
1887 
1888 /* Create "default" multicast route to the interface */
1889 
1890 static void addrconf_add_mroute(struct net_device *dev)
1891 {
1892 	struct fib6_config cfg = {
1893 		.fc_table = RT6_TABLE_LOCAL,
1894 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
1895 		.fc_ifindex = dev->ifindex,
1896 		.fc_dst_len = 8,
1897 		.fc_flags = RTF_UP,
1898 		.fc_nlinfo.nl_net = dev_net(dev),
1899 	};
1900 
1901 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
1902 
1903 	ip6_route_add(&cfg);
1904 }
1905 
1906 #if IS_ENABLED(CONFIG_IPV6_SIT)
1907 static void sit_route_add(struct net_device *dev)
1908 {
1909 	struct fib6_config cfg = {
1910 		.fc_table = RT6_TABLE_MAIN,
1911 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
1912 		.fc_ifindex = dev->ifindex,
1913 		.fc_dst_len = 96,
1914 		.fc_flags = RTF_UP | RTF_NONEXTHOP,
1915 		.fc_nlinfo.nl_net = dev_net(dev),
1916 	};
1917 
1918 	/* prefix length - 96 bits "::d.d.d.d" */
1919 	ip6_route_add(&cfg);
1920 }
1921 #endif
1922 
1923 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
1924 {
1925 	struct inet6_dev *idev;
1926 
1927 	ASSERT_RTNL();
1928 
1929 	idev = ipv6_find_idev(dev);
1930 	if (!idev)
1931 		return ERR_PTR(-ENOBUFS);
1932 
1933 	if (idev->cnf.disable_ipv6)
1934 		return ERR_PTR(-EACCES);
1935 
1936 	/* Add default multicast route */
1937 	if (!(dev->flags & IFF_LOOPBACK))
1938 		addrconf_add_mroute(dev);
1939 
1940 	return idev;
1941 }
1942 
1943 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
1944 {
1945 	struct prefix_info *pinfo;
1946 	__u32 valid_lft;
1947 	__u32 prefered_lft;
1948 	int addr_type;
1949 	struct inet6_dev *in6_dev;
1950 	struct net *net = dev_net(dev);
1951 
1952 	pinfo = (struct prefix_info *) opt;
1953 
1954 	if (len < sizeof(struct prefix_info)) {
1955 		ADBG(("addrconf: prefix option too short\n"));
1956 		return;
1957 	}
1958 
1959 	/*
1960 	 *	Validation checks ([ADDRCONF], page 19)
1961 	 */
1962 
1963 	addr_type = ipv6_addr_type(&pinfo->prefix);
1964 
1965 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
1966 		return;
1967 
1968 	valid_lft = ntohl(pinfo->valid);
1969 	prefered_lft = ntohl(pinfo->prefered);
1970 
1971 	if (prefered_lft > valid_lft) {
1972 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
1973 		return;
1974 	}
1975 
1976 	in6_dev = in6_dev_get(dev);
1977 
1978 	if (in6_dev == NULL) {
1979 		net_dbg_ratelimited("addrconf: device %s not configured\n",
1980 				    dev->name);
1981 		return;
1982 	}
1983 
1984 	/*
1985 	 *	Two things going on here:
1986 	 *	1) Add routes for on-link prefixes
1987 	 *	2) Configure prefixes with the auto flag set
1988 	 */
1989 
1990 	if (pinfo->onlink) {
1991 		struct rt6_info *rt;
1992 		unsigned long rt_expires;
1993 
1994 		/* Avoid arithmetic overflow. Really, we could
1995 		 * save rt_expires in seconds, likely valid_lft,
1996 		 * but it would require division in fib gc, that it
1997 		 * not good.
1998 		 */
1999 		if (HZ > USER_HZ)
2000 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2001 		else
2002 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2003 
2004 		if (addrconf_finite_timeout(rt_expires))
2005 			rt_expires *= HZ;
2006 
2007 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2008 					       pinfo->prefix_len,
2009 					       dev,
2010 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2011 					       RTF_GATEWAY | RTF_DEFAULT);
2012 
2013 		if (rt) {
2014 			/* Autoconf prefix route */
2015 			if (valid_lft == 0) {
2016 				ip6_del_rt(rt);
2017 				rt = NULL;
2018 			} else if (addrconf_finite_timeout(rt_expires)) {
2019 				/* not infinity */
2020 				rt6_set_expires(rt, jiffies + rt_expires);
2021 			} else {
2022 				rt6_clean_expires(rt);
2023 			}
2024 		} else if (valid_lft) {
2025 			clock_t expires = 0;
2026 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2027 			if (addrconf_finite_timeout(rt_expires)) {
2028 				/* not infinity */
2029 				flags |= RTF_EXPIRES;
2030 				expires = jiffies_to_clock_t(rt_expires);
2031 			}
2032 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2033 					      dev, expires, flags);
2034 		}
2035 		ip6_rt_put(rt);
2036 	}
2037 
2038 	/* Try to figure out our local address for this prefix */
2039 
2040 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2041 		struct inet6_ifaddr *ifp;
2042 		struct in6_addr addr;
2043 		int create = 0, update_lft = 0;
2044 
2045 		if (pinfo->prefix_len == 64) {
2046 			memcpy(&addr, &pinfo->prefix, 8);
2047 			if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2048 			    ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2049 				in6_dev_put(in6_dev);
2050 				return;
2051 			}
2052 			goto ok;
2053 		}
2054 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2055 				    pinfo->prefix_len);
2056 		in6_dev_put(in6_dev);
2057 		return;
2058 
2059 ok:
2060 
2061 		ifp = ipv6_get_ifaddr(net, &addr, dev, 1);
2062 
2063 		if (ifp == NULL && valid_lft) {
2064 			int max_addresses = in6_dev->cnf.max_addresses;
2065 			u32 addr_flags = 0;
2066 
2067 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2068 			if (in6_dev->cnf.optimistic_dad &&
2069 			    !net->ipv6.devconf_all->forwarding && sllao)
2070 				addr_flags = IFA_F_OPTIMISTIC;
2071 #endif
2072 
2073 			/* Do not allow to create too much of autoconfigured
2074 			 * addresses; this would be too easy way to crash kernel.
2075 			 */
2076 			if (!max_addresses ||
2077 			    ipv6_count_addresses(in6_dev) < max_addresses)
2078 				ifp = ipv6_add_addr(in6_dev, &addr, pinfo->prefix_len,
2079 						    addr_type&IPV6_ADDR_SCOPE_MASK,
2080 						    addr_flags);
2081 
2082 			if (!ifp || IS_ERR(ifp)) {
2083 				in6_dev_put(in6_dev);
2084 				return;
2085 			}
2086 
2087 			update_lft = create = 1;
2088 			ifp->cstamp = jiffies;
2089 			addrconf_dad_start(ifp);
2090 		}
2091 
2092 		if (ifp) {
2093 			int flags;
2094 			unsigned long now;
2095 #ifdef CONFIG_IPV6_PRIVACY
2096 			struct inet6_ifaddr *ift;
2097 #endif
2098 			u32 stored_lft;
2099 
2100 			/* update lifetime (RFC2462 5.5.3 e) */
2101 			spin_lock(&ifp->lock);
2102 			now = jiffies;
2103 			if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2104 				stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2105 			else
2106 				stored_lft = 0;
2107 			if (!update_lft && stored_lft) {
2108 				if (valid_lft > MIN_VALID_LIFETIME ||
2109 				    valid_lft > stored_lft)
2110 					update_lft = 1;
2111 				else if (stored_lft <= MIN_VALID_LIFETIME) {
2112 					/* valid_lft <= stored_lft is always true */
2113 					/*
2114 					 * RFC 4862 Section 5.5.3e:
2115 					 * "Note that the preferred lifetime of
2116 					 *  the corresponding address is always
2117 					 *  reset to the Preferred Lifetime in
2118 					 *  the received Prefix Information
2119 					 *  option, regardless of whether the
2120 					 *  valid lifetime is also reset or
2121 					 *  ignored."
2122 					 *
2123 					 *  So if the preferred lifetime in
2124 					 *  this advertisement is different
2125 					 *  than what we have stored, but the
2126 					 *  valid lifetime is invalid, just
2127 					 *  reset prefered_lft.
2128 					 *
2129 					 *  We must set the valid lifetime
2130 					 *  to the stored lifetime since we'll
2131 					 *  be updating the timestamp below,
2132 					 *  else we'll set it back to the
2133 					 *  minimum.
2134 					 */
2135 					if (prefered_lft != ifp->prefered_lft) {
2136 						valid_lft = stored_lft;
2137 						update_lft = 1;
2138 					}
2139 				} else {
2140 					valid_lft = MIN_VALID_LIFETIME;
2141 					if (valid_lft < prefered_lft)
2142 						prefered_lft = valid_lft;
2143 					update_lft = 1;
2144 				}
2145 			}
2146 
2147 			if (update_lft) {
2148 				ifp->valid_lft = valid_lft;
2149 				ifp->prefered_lft = prefered_lft;
2150 				ifp->tstamp = now;
2151 				flags = ifp->flags;
2152 				ifp->flags &= ~IFA_F_DEPRECATED;
2153 				spin_unlock(&ifp->lock);
2154 
2155 				if (!(flags&IFA_F_TENTATIVE))
2156 					ipv6_ifa_notify(0, ifp);
2157 			} else
2158 				spin_unlock(&ifp->lock);
2159 
2160 #ifdef CONFIG_IPV6_PRIVACY
2161 			read_lock_bh(&in6_dev->lock);
2162 			/* update all temporary addresses in the list */
2163 			list_for_each_entry(ift, &in6_dev->tempaddr_list,
2164 					    tmp_list) {
2165 				int age, max_valid, max_prefered;
2166 
2167 				if (ifp != ift->ifpub)
2168 					continue;
2169 
2170 				/*
2171 				 * RFC 4941 section 3.3:
2172 				 * If a received option will extend the lifetime
2173 				 * of a public address, the lifetimes of
2174 				 * temporary addresses should be extended,
2175 				 * subject to the overall constraint that no
2176 				 * temporary addresses should ever remain
2177 				 * "valid" or "preferred" for a time longer than
2178 				 * (TEMP_VALID_LIFETIME) or
2179 				 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR),
2180 				 * respectively.
2181 				 */
2182 				age = (now - ift->cstamp) / HZ;
2183 				max_valid = in6_dev->cnf.temp_valid_lft - age;
2184 				if (max_valid < 0)
2185 					max_valid = 0;
2186 
2187 				max_prefered = in6_dev->cnf.temp_prefered_lft -
2188 					       in6_dev->cnf.max_desync_factor -
2189 					       age;
2190 				if (max_prefered < 0)
2191 					max_prefered = 0;
2192 
2193 				if (valid_lft > max_valid)
2194 					valid_lft = max_valid;
2195 
2196 				if (prefered_lft > max_prefered)
2197 					prefered_lft = max_prefered;
2198 
2199 				spin_lock(&ift->lock);
2200 				flags = ift->flags;
2201 				ift->valid_lft = valid_lft;
2202 				ift->prefered_lft = prefered_lft;
2203 				ift->tstamp = now;
2204 				if (prefered_lft > 0)
2205 					ift->flags &= ~IFA_F_DEPRECATED;
2206 
2207 				spin_unlock(&ift->lock);
2208 				if (!(flags&IFA_F_TENTATIVE))
2209 					ipv6_ifa_notify(0, ift);
2210 			}
2211 
2212 			if ((create || list_empty(&in6_dev->tempaddr_list)) && in6_dev->cnf.use_tempaddr > 0) {
2213 				/*
2214 				 * When a new public address is created as
2215 				 * described in [ADDRCONF], also create a new
2216 				 * temporary address. Also create a temporary
2217 				 * address if it's enabled but no temporary
2218 				 * address currently exists.
2219 				 */
2220 				read_unlock_bh(&in6_dev->lock);
2221 				ipv6_create_tempaddr(ifp, NULL);
2222 			} else {
2223 				read_unlock_bh(&in6_dev->lock);
2224 			}
2225 #endif
2226 			in6_ifa_put(ifp);
2227 			addrconf_verify(0);
2228 		}
2229 	}
2230 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2231 	in6_dev_put(in6_dev);
2232 }
2233 
2234 /*
2235  *	Set destination address.
2236  *	Special case for SIT interfaces where we create a new "virtual"
2237  *	device.
2238  */
2239 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2240 {
2241 	struct in6_ifreq ireq;
2242 	struct net_device *dev;
2243 	int err = -EINVAL;
2244 
2245 	rtnl_lock();
2246 
2247 	err = -EFAULT;
2248 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2249 		goto err_exit;
2250 
2251 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2252 
2253 	err = -ENODEV;
2254 	if (dev == NULL)
2255 		goto err_exit;
2256 
2257 #if IS_ENABLED(CONFIG_IPV6_SIT)
2258 	if (dev->type == ARPHRD_SIT) {
2259 		const struct net_device_ops *ops = dev->netdev_ops;
2260 		struct ifreq ifr;
2261 		struct ip_tunnel_parm p;
2262 
2263 		err = -EADDRNOTAVAIL;
2264 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2265 			goto err_exit;
2266 
2267 		memset(&p, 0, sizeof(p));
2268 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2269 		p.iph.saddr = 0;
2270 		p.iph.version = 4;
2271 		p.iph.ihl = 5;
2272 		p.iph.protocol = IPPROTO_IPV6;
2273 		p.iph.ttl = 64;
2274 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2275 
2276 		if (ops->ndo_do_ioctl) {
2277 			mm_segment_t oldfs = get_fs();
2278 
2279 			set_fs(KERNEL_DS);
2280 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2281 			set_fs(oldfs);
2282 		} else
2283 			err = -EOPNOTSUPP;
2284 
2285 		if (err == 0) {
2286 			err = -ENOBUFS;
2287 			dev = __dev_get_by_name(net, p.name);
2288 			if (!dev)
2289 				goto err_exit;
2290 			err = dev_open(dev);
2291 		}
2292 	}
2293 #endif
2294 
2295 err_exit:
2296 	rtnl_unlock();
2297 	return err;
2298 }
2299 
2300 /*
2301  *	Manual configuration of address on an interface
2302  */
2303 static int inet6_addr_add(struct net *net, int ifindex, const struct in6_addr *pfx,
2304 			  unsigned int plen, __u8 ifa_flags, __u32 prefered_lft,
2305 			  __u32 valid_lft)
2306 {
2307 	struct inet6_ifaddr *ifp;
2308 	struct inet6_dev *idev;
2309 	struct net_device *dev;
2310 	int scope;
2311 	u32 flags;
2312 	clock_t expires;
2313 	unsigned long timeout;
2314 
2315 	ASSERT_RTNL();
2316 
2317 	if (plen > 128)
2318 		return -EINVAL;
2319 
2320 	/* check the lifetime */
2321 	if (!valid_lft || prefered_lft > valid_lft)
2322 		return -EINVAL;
2323 
2324 	dev = __dev_get_by_index(net, ifindex);
2325 	if (!dev)
2326 		return -ENODEV;
2327 
2328 	idev = addrconf_add_dev(dev);
2329 	if (IS_ERR(idev))
2330 		return PTR_ERR(idev);
2331 
2332 	scope = ipv6_addr_scope(pfx);
2333 
2334 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
2335 	if (addrconf_finite_timeout(timeout)) {
2336 		expires = jiffies_to_clock_t(timeout * HZ);
2337 		valid_lft = timeout;
2338 		flags = RTF_EXPIRES;
2339 	} else {
2340 		expires = 0;
2341 		flags = 0;
2342 		ifa_flags |= IFA_F_PERMANENT;
2343 	}
2344 
2345 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
2346 	if (addrconf_finite_timeout(timeout)) {
2347 		if (timeout == 0)
2348 			ifa_flags |= IFA_F_DEPRECATED;
2349 		prefered_lft = timeout;
2350 	}
2351 
2352 	ifp = ipv6_add_addr(idev, pfx, plen, scope, ifa_flags);
2353 
2354 	if (!IS_ERR(ifp)) {
2355 		spin_lock_bh(&ifp->lock);
2356 		ifp->valid_lft = valid_lft;
2357 		ifp->prefered_lft = prefered_lft;
2358 		ifp->tstamp = jiffies;
2359 		spin_unlock_bh(&ifp->lock);
2360 
2361 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev,
2362 				      expires, flags);
2363 		/*
2364 		 * Note that section 3.1 of RFC 4429 indicates
2365 		 * that the Optimistic flag should not be set for
2366 		 * manually configured addresses
2367 		 */
2368 		addrconf_dad_start(ifp);
2369 		in6_ifa_put(ifp);
2370 		addrconf_verify(0);
2371 		return 0;
2372 	}
2373 
2374 	return PTR_ERR(ifp);
2375 }
2376 
2377 static int inet6_addr_del(struct net *net, int ifindex, const struct in6_addr *pfx,
2378 			  unsigned int plen)
2379 {
2380 	struct inet6_ifaddr *ifp;
2381 	struct inet6_dev *idev;
2382 	struct net_device *dev;
2383 
2384 	if (plen > 128)
2385 		return -EINVAL;
2386 
2387 	dev = __dev_get_by_index(net, ifindex);
2388 	if (!dev)
2389 		return -ENODEV;
2390 
2391 	if ((idev = __in6_dev_get(dev)) == NULL)
2392 		return -ENXIO;
2393 
2394 	read_lock_bh(&idev->lock);
2395 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
2396 		if (ifp->prefix_len == plen &&
2397 		    ipv6_addr_equal(pfx, &ifp->addr)) {
2398 			in6_ifa_hold(ifp);
2399 			read_unlock_bh(&idev->lock);
2400 
2401 			ipv6_del_addr(ifp);
2402 
2403 			/* If the last address is deleted administratively,
2404 			   disable IPv6 on this interface.
2405 			 */
2406 			if (list_empty(&idev->addr_list))
2407 				addrconf_ifdown(idev->dev, 1);
2408 			return 0;
2409 		}
2410 	}
2411 	read_unlock_bh(&idev->lock);
2412 	return -EADDRNOTAVAIL;
2413 }
2414 
2415 
2416 int addrconf_add_ifaddr(struct net *net, void __user *arg)
2417 {
2418 	struct in6_ifreq ireq;
2419 	int err;
2420 
2421 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2422 		return -EPERM;
2423 
2424 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2425 		return -EFAULT;
2426 
2427 	rtnl_lock();
2428 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &ireq.ifr6_addr,
2429 			     ireq.ifr6_prefixlen, IFA_F_PERMANENT,
2430 			     INFINITY_LIFE_TIME, INFINITY_LIFE_TIME);
2431 	rtnl_unlock();
2432 	return err;
2433 }
2434 
2435 int addrconf_del_ifaddr(struct net *net, void __user *arg)
2436 {
2437 	struct in6_ifreq ireq;
2438 	int err;
2439 
2440 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
2441 		return -EPERM;
2442 
2443 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2444 		return -EFAULT;
2445 
2446 	rtnl_lock();
2447 	err = inet6_addr_del(net, ireq.ifr6_ifindex, &ireq.ifr6_addr,
2448 			     ireq.ifr6_prefixlen);
2449 	rtnl_unlock();
2450 	return err;
2451 }
2452 
2453 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
2454 		     int plen, int scope)
2455 {
2456 	struct inet6_ifaddr *ifp;
2457 
2458 	ifp = ipv6_add_addr(idev, addr, plen, scope, IFA_F_PERMANENT);
2459 	if (!IS_ERR(ifp)) {
2460 		spin_lock_bh(&ifp->lock);
2461 		ifp->flags &= ~IFA_F_TENTATIVE;
2462 		spin_unlock_bh(&ifp->lock);
2463 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
2464 		in6_ifa_put(ifp);
2465 	}
2466 }
2467 
2468 #if IS_ENABLED(CONFIG_IPV6_SIT)
2469 static void sit_add_v4_addrs(struct inet6_dev *idev)
2470 {
2471 	struct in6_addr addr;
2472 	struct net_device *dev;
2473 	struct net *net = dev_net(idev->dev);
2474 	int scope;
2475 
2476 	ASSERT_RTNL();
2477 
2478 	memset(&addr, 0, sizeof(struct in6_addr));
2479 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
2480 
2481 	if (idev->dev->flags&IFF_POINTOPOINT) {
2482 		addr.s6_addr32[0] = htonl(0xfe800000);
2483 		scope = IFA_LINK;
2484 	} else {
2485 		scope = IPV6_ADDR_COMPATv4;
2486 	}
2487 
2488 	if (addr.s6_addr32[3]) {
2489 		add_addr(idev, &addr, 128, scope);
2490 		return;
2491 	}
2492 
2493 	for_each_netdev(net, dev) {
2494 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
2495 		if (in_dev && (dev->flags & IFF_UP)) {
2496 			struct in_ifaddr *ifa;
2497 
2498 			int flag = scope;
2499 
2500 			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
2501 				int plen;
2502 
2503 				addr.s6_addr32[3] = ifa->ifa_local;
2504 
2505 				if (ifa->ifa_scope == RT_SCOPE_LINK)
2506 					continue;
2507 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
2508 					if (idev->dev->flags&IFF_POINTOPOINT)
2509 						continue;
2510 					flag |= IFA_HOST;
2511 				}
2512 				if (idev->dev->flags&IFF_POINTOPOINT)
2513 					plen = 64;
2514 				else
2515 					plen = 96;
2516 
2517 				add_addr(idev, &addr, plen, flag);
2518 			}
2519 		}
2520 	}
2521 }
2522 #endif
2523 
2524 static void init_loopback(struct net_device *dev)
2525 {
2526 	struct inet6_dev  *idev;
2527 
2528 	/* ::1 */
2529 
2530 	ASSERT_RTNL();
2531 
2532 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2533 		pr_debug("%s: add_dev failed\n", __func__);
2534 		return;
2535 	}
2536 
2537 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
2538 }
2539 
2540 static void addrconf_add_linklocal(struct inet6_dev *idev, const struct in6_addr *addr)
2541 {
2542 	struct inet6_ifaddr *ifp;
2543 	u32 addr_flags = IFA_F_PERMANENT;
2544 
2545 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2546 	if (idev->cnf.optimistic_dad &&
2547 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
2548 		addr_flags |= IFA_F_OPTIMISTIC;
2549 #endif
2550 
2551 
2552 	ifp = ipv6_add_addr(idev, addr, 64, IFA_LINK, addr_flags);
2553 	if (!IS_ERR(ifp)) {
2554 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, idev->dev, 0, 0);
2555 		addrconf_dad_start(ifp);
2556 		in6_ifa_put(ifp);
2557 	}
2558 }
2559 
2560 static void addrconf_dev_config(struct net_device *dev)
2561 {
2562 	struct in6_addr addr;
2563 	struct inet6_dev *idev;
2564 
2565 	ASSERT_RTNL();
2566 
2567 	if ((dev->type != ARPHRD_ETHER) &&
2568 	    (dev->type != ARPHRD_FDDI) &&
2569 	    (dev->type != ARPHRD_ARCNET) &&
2570 	    (dev->type != ARPHRD_INFINIBAND) &&
2571 	    (dev->type != ARPHRD_IEEE802154)) {
2572 		/* Alas, we support only Ethernet autoconfiguration. */
2573 		return;
2574 	}
2575 
2576 	idev = addrconf_add_dev(dev);
2577 	if (IS_ERR(idev))
2578 		return;
2579 
2580 	memset(&addr, 0, sizeof(struct in6_addr));
2581 	addr.s6_addr32[0] = htonl(0xFE800000);
2582 
2583 	if (ipv6_generate_eui64(addr.s6_addr + 8, dev) == 0)
2584 		addrconf_add_linklocal(idev, &addr);
2585 }
2586 
2587 #if IS_ENABLED(CONFIG_IPV6_SIT)
2588 static void addrconf_sit_config(struct net_device *dev)
2589 {
2590 	struct inet6_dev *idev;
2591 
2592 	ASSERT_RTNL();
2593 
2594 	/*
2595 	 * Configure the tunnel with one of our IPv4
2596 	 * addresses... we should configure all of
2597 	 * our v4 addrs in the tunnel
2598 	 */
2599 
2600 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2601 		pr_debug("%s: add_dev failed\n", __func__);
2602 		return;
2603 	}
2604 
2605 	if (dev->priv_flags & IFF_ISATAP) {
2606 		struct in6_addr addr;
2607 
2608 		ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
2609 		addrconf_prefix_route(&addr, 64, dev, 0, 0);
2610 		if (!ipv6_generate_eui64(addr.s6_addr + 8, dev))
2611 			addrconf_add_linklocal(idev, &addr);
2612 		return;
2613 	}
2614 
2615 	sit_add_v4_addrs(idev);
2616 
2617 	if (dev->flags&IFF_POINTOPOINT)
2618 		addrconf_add_mroute(dev);
2619 	else
2620 		sit_route_add(dev);
2621 }
2622 #endif
2623 
2624 #if IS_ENABLED(CONFIG_NET_IPGRE)
2625 static void addrconf_gre_config(struct net_device *dev)
2626 {
2627 	struct inet6_dev *idev;
2628 	struct in6_addr addr;
2629 
2630 	pr_info("%s(%s)\n", __func__, dev->name);
2631 
2632 	ASSERT_RTNL();
2633 
2634 	if ((idev = ipv6_find_idev(dev)) == NULL) {
2635 		pr_debug("%s: add_dev failed\n", __func__);
2636 		return;
2637 	}
2638 
2639 	ipv6_addr_set(&addr,  htonl(0xFE800000), 0, 0, 0);
2640 	addrconf_prefix_route(&addr, 64, dev, 0, 0);
2641 
2642 	if (!ipv6_generate_eui64(addr.s6_addr + 8, dev))
2643 		addrconf_add_linklocal(idev, &addr);
2644 }
2645 #endif
2646 
2647 static inline int
2648 ipv6_inherit_linklocal(struct inet6_dev *idev, struct net_device *link_dev)
2649 {
2650 	struct in6_addr lladdr;
2651 
2652 	if (!ipv6_get_lladdr(link_dev, &lladdr, IFA_F_TENTATIVE)) {
2653 		addrconf_add_linklocal(idev, &lladdr);
2654 		return 0;
2655 	}
2656 	return -1;
2657 }
2658 
2659 static void ip6_tnl_add_linklocal(struct inet6_dev *idev)
2660 {
2661 	struct net_device *link_dev;
2662 	struct net *net = dev_net(idev->dev);
2663 
2664 	/* first try to inherit the link-local address from the link device */
2665 	if (idev->dev->iflink &&
2666 	    (link_dev = __dev_get_by_index(net, idev->dev->iflink))) {
2667 		if (!ipv6_inherit_linklocal(idev, link_dev))
2668 			return;
2669 	}
2670 	/* then try to inherit it from any device */
2671 	for_each_netdev(net, link_dev) {
2672 		if (!ipv6_inherit_linklocal(idev, link_dev))
2673 			return;
2674 	}
2675 	pr_debug("init ip6-ip6: add_linklocal failed\n");
2676 }
2677 
2678 /*
2679  * Autoconfigure tunnel with a link-local address so routing protocols,
2680  * DHCPv6, MLD etc. can be run over the virtual link
2681  */
2682 
2683 static void addrconf_ip6_tnl_config(struct net_device *dev)
2684 {
2685 	struct inet6_dev *idev;
2686 
2687 	ASSERT_RTNL();
2688 
2689 	idev = addrconf_add_dev(dev);
2690 	if (IS_ERR(idev)) {
2691 		pr_debug("init ip6-ip6: add_dev failed\n");
2692 		return;
2693 	}
2694 	ip6_tnl_add_linklocal(idev);
2695 }
2696 
2697 static int addrconf_notify(struct notifier_block *this, unsigned long event,
2698 			   void *data)
2699 {
2700 	struct net_device *dev = (struct net_device *) data;
2701 	struct inet6_dev *idev = __in6_dev_get(dev);
2702 	int run_pending = 0;
2703 	int err;
2704 
2705 	switch (event) {
2706 	case NETDEV_REGISTER:
2707 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2708 			idev = ipv6_add_dev(dev);
2709 			if (!idev)
2710 				return notifier_from_errno(-ENOMEM);
2711 		}
2712 		break;
2713 
2714 	case NETDEV_UP:
2715 	case NETDEV_CHANGE:
2716 		if (dev->flags & IFF_SLAVE)
2717 			break;
2718 
2719 		if (event == NETDEV_UP) {
2720 			if (!addrconf_qdisc_ok(dev)) {
2721 				/* device is not ready yet. */
2722 				pr_info("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
2723 					dev->name);
2724 				break;
2725 			}
2726 
2727 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
2728 				idev = ipv6_add_dev(dev);
2729 
2730 			if (idev) {
2731 				idev->if_flags |= IF_READY;
2732 				run_pending = 1;
2733 			}
2734 		} else {
2735 			if (!addrconf_qdisc_ok(dev)) {
2736 				/* device is still not ready. */
2737 				break;
2738 			}
2739 
2740 			if (idev) {
2741 				if (idev->if_flags & IF_READY)
2742 					/* device is already configured. */
2743 					break;
2744 				idev->if_flags |= IF_READY;
2745 			}
2746 
2747 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
2748 				dev->name);
2749 
2750 			run_pending = 1;
2751 		}
2752 
2753 		switch (dev->type) {
2754 #if IS_ENABLED(CONFIG_IPV6_SIT)
2755 		case ARPHRD_SIT:
2756 			addrconf_sit_config(dev);
2757 			break;
2758 #endif
2759 #if IS_ENABLED(CONFIG_NET_IPGRE)
2760 		case ARPHRD_IPGRE:
2761 			addrconf_gre_config(dev);
2762 			break;
2763 #endif
2764 		case ARPHRD_TUNNEL6:
2765 			addrconf_ip6_tnl_config(dev);
2766 			break;
2767 		case ARPHRD_LOOPBACK:
2768 			init_loopback(dev);
2769 			break;
2770 
2771 		default:
2772 			addrconf_dev_config(dev);
2773 			break;
2774 		}
2775 
2776 		if (idev) {
2777 			if (run_pending)
2778 				addrconf_dad_run(idev);
2779 
2780 			/*
2781 			 * If the MTU changed during the interface down,
2782 			 * when the interface up, the changed MTU must be
2783 			 * reflected in the idev as well as routers.
2784 			 */
2785 			if (idev->cnf.mtu6 != dev->mtu &&
2786 			    dev->mtu >= IPV6_MIN_MTU) {
2787 				rt6_mtu_change(dev, dev->mtu);
2788 				idev->cnf.mtu6 = dev->mtu;
2789 			}
2790 			idev->tstamp = jiffies;
2791 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
2792 
2793 			/*
2794 			 * If the changed mtu during down is lower than
2795 			 * IPV6_MIN_MTU stop IPv6 on this interface.
2796 			 */
2797 			if (dev->mtu < IPV6_MIN_MTU)
2798 				addrconf_ifdown(dev, 1);
2799 		}
2800 		break;
2801 
2802 	case NETDEV_CHANGEMTU:
2803 		if (idev && dev->mtu >= IPV6_MIN_MTU) {
2804 			rt6_mtu_change(dev, dev->mtu);
2805 			idev->cnf.mtu6 = dev->mtu;
2806 			break;
2807 		}
2808 
2809 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
2810 			idev = ipv6_add_dev(dev);
2811 			if (idev)
2812 				break;
2813 		}
2814 
2815 		/*
2816 		 * MTU falled under IPV6_MIN_MTU.
2817 		 * Stop IPv6 on this interface.
2818 		 */
2819 
2820 	case NETDEV_DOWN:
2821 	case NETDEV_UNREGISTER:
2822 		/*
2823 		 *	Remove all addresses from this interface.
2824 		 */
2825 		addrconf_ifdown(dev, event != NETDEV_DOWN);
2826 		break;
2827 
2828 	case NETDEV_CHANGENAME:
2829 		if (idev) {
2830 			snmp6_unregister_dev(idev);
2831 			addrconf_sysctl_unregister(idev);
2832 			addrconf_sysctl_register(idev);
2833 			err = snmp6_register_dev(idev);
2834 			if (err)
2835 				return notifier_from_errno(err);
2836 		}
2837 		break;
2838 
2839 	case NETDEV_PRE_TYPE_CHANGE:
2840 	case NETDEV_POST_TYPE_CHANGE:
2841 		addrconf_type_change(dev, event);
2842 		break;
2843 	}
2844 
2845 	return NOTIFY_OK;
2846 }
2847 
2848 /*
2849  *	addrconf module should be notified of a device going up
2850  */
2851 static struct notifier_block ipv6_dev_notf = {
2852 	.notifier_call = addrconf_notify,
2853 };
2854 
2855 static void addrconf_type_change(struct net_device *dev, unsigned long event)
2856 {
2857 	struct inet6_dev *idev;
2858 	ASSERT_RTNL();
2859 
2860 	idev = __in6_dev_get(dev);
2861 
2862 	if (event == NETDEV_POST_TYPE_CHANGE)
2863 		ipv6_mc_remap(idev);
2864 	else if (event == NETDEV_PRE_TYPE_CHANGE)
2865 		ipv6_mc_unmap(idev);
2866 }
2867 
2868 static int addrconf_ifdown(struct net_device *dev, int how)
2869 {
2870 	struct net *net = dev_net(dev);
2871 	struct inet6_dev *idev;
2872 	struct inet6_ifaddr *ifa;
2873 	int state, i;
2874 
2875 	ASSERT_RTNL();
2876 
2877 	rt6_ifdown(net, dev);
2878 	neigh_ifdown(&nd_tbl, dev);
2879 
2880 	idev = __in6_dev_get(dev);
2881 	if (idev == NULL)
2882 		return -ENODEV;
2883 
2884 	/*
2885 	 * Step 1: remove reference to ipv6 device from parent device.
2886 	 *	   Do not dev_put!
2887 	 */
2888 	if (how) {
2889 		idev->dead = 1;
2890 
2891 		/* protected by rtnl_lock */
2892 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
2893 
2894 		/* Step 1.5: remove snmp6 entry */
2895 		snmp6_unregister_dev(idev);
2896 
2897 	}
2898 
2899 	/* Step 2: clear hash table */
2900 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
2901 		struct hlist_head *h = &inet6_addr_lst[i];
2902 		struct hlist_node *n;
2903 
2904 		spin_lock_bh(&addrconf_hash_lock);
2905 	restart:
2906 		hlist_for_each_entry_rcu(ifa, n, h, addr_lst) {
2907 			if (ifa->idev == idev) {
2908 				hlist_del_init_rcu(&ifa->addr_lst);
2909 				addrconf_del_timer(ifa);
2910 				goto restart;
2911 			}
2912 		}
2913 		spin_unlock_bh(&addrconf_hash_lock);
2914 	}
2915 
2916 	write_lock_bh(&idev->lock);
2917 
2918 	/* Step 2: clear flags for stateless addrconf */
2919 	if (!how)
2920 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
2921 
2922 #ifdef CONFIG_IPV6_PRIVACY
2923 	if (how && del_timer(&idev->regen_timer))
2924 		in6_dev_put(idev);
2925 
2926 	/* Step 3: clear tempaddr list */
2927 	while (!list_empty(&idev->tempaddr_list)) {
2928 		ifa = list_first_entry(&idev->tempaddr_list,
2929 				       struct inet6_ifaddr, tmp_list);
2930 		list_del(&ifa->tmp_list);
2931 		write_unlock_bh(&idev->lock);
2932 		spin_lock_bh(&ifa->lock);
2933 
2934 		if (ifa->ifpub) {
2935 			in6_ifa_put(ifa->ifpub);
2936 			ifa->ifpub = NULL;
2937 		}
2938 		spin_unlock_bh(&ifa->lock);
2939 		in6_ifa_put(ifa);
2940 		write_lock_bh(&idev->lock);
2941 	}
2942 #endif
2943 
2944 	while (!list_empty(&idev->addr_list)) {
2945 		ifa = list_first_entry(&idev->addr_list,
2946 				       struct inet6_ifaddr, if_list);
2947 		addrconf_del_timer(ifa);
2948 
2949 		list_del(&ifa->if_list);
2950 
2951 		write_unlock_bh(&idev->lock);
2952 
2953 		spin_lock_bh(&ifa->state_lock);
2954 		state = ifa->state;
2955 		ifa->state = INET6_IFADDR_STATE_DEAD;
2956 		spin_unlock_bh(&ifa->state_lock);
2957 
2958 		if (state != INET6_IFADDR_STATE_DEAD) {
2959 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
2960 			atomic_notifier_call_chain(&inet6addr_chain, NETDEV_DOWN, ifa);
2961 		}
2962 		in6_ifa_put(ifa);
2963 
2964 		write_lock_bh(&idev->lock);
2965 	}
2966 
2967 	write_unlock_bh(&idev->lock);
2968 
2969 	/* Step 5: Discard multicast list */
2970 	if (how)
2971 		ipv6_mc_destroy_dev(idev);
2972 	else
2973 		ipv6_mc_down(idev);
2974 
2975 	idev->tstamp = jiffies;
2976 
2977 	/* Last: Shot the device (if unregistered) */
2978 	if (how) {
2979 		addrconf_sysctl_unregister(idev);
2980 		neigh_parms_release(&nd_tbl, idev->nd_parms);
2981 		neigh_ifdown(&nd_tbl, dev);
2982 		in6_dev_put(idev);
2983 	}
2984 	return 0;
2985 }
2986 
2987 static void addrconf_rs_timer(unsigned long data)
2988 {
2989 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *) data;
2990 	struct inet6_dev *idev = ifp->idev;
2991 
2992 	read_lock(&idev->lock);
2993 	if (idev->dead || !(idev->if_flags & IF_READY))
2994 		goto out;
2995 
2996 	if (!ipv6_accept_ra(idev))
2997 		goto out;
2998 
2999 	/* Announcement received after solicitation was sent */
3000 	if (idev->if_flags & IF_RA_RCVD)
3001 		goto out;
3002 
3003 	spin_lock(&ifp->lock);
3004 	if (ifp->probes++ < idev->cnf.rtr_solicits) {
3005 		/* The wait after the last probe can be shorter */
3006 		addrconf_mod_timer(ifp, AC_RS,
3007 				   (ifp->probes == idev->cnf.rtr_solicits) ?
3008 				   idev->cnf.rtr_solicit_delay :
3009 				   idev->cnf.rtr_solicit_interval);
3010 		spin_unlock(&ifp->lock);
3011 
3012 		ndisc_send_rs(idev->dev, &ifp->addr, &in6addr_linklocal_allrouters);
3013 	} else {
3014 		spin_unlock(&ifp->lock);
3015 		/*
3016 		 * Note: we do not support deprecated "all on-link"
3017 		 * assumption any longer.
3018 		 */
3019 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3020 	}
3021 
3022 out:
3023 	read_unlock(&idev->lock);
3024 	in6_ifa_put(ifp);
3025 }
3026 
3027 /*
3028  *	Duplicate Address Detection
3029  */
3030 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3031 {
3032 	unsigned long rand_num;
3033 	struct inet6_dev *idev = ifp->idev;
3034 
3035 	if (ifp->flags & IFA_F_OPTIMISTIC)
3036 		rand_num = 0;
3037 	else
3038 		rand_num = net_random() % (idev->cnf.rtr_solicit_delay ? : 1);
3039 
3040 	ifp->probes = idev->cnf.dad_transmits;
3041 	addrconf_mod_timer(ifp, AC_DAD, rand_num);
3042 }
3043 
3044 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
3045 {
3046 	struct inet6_dev *idev = ifp->idev;
3047 	struct net_device *dev = idev->dev;
3048 
3049 	addrconf_join_solict(dev, &ifp->addr);
3050 
3051 	net_srandom(ifp->addr.s6_addr32[3]);
3052 
3053 	read_lock_bh(&idev->lock);
3054 	spin_lock(&ifp->lock);
3055 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3056 		goto out;
3057 
3058 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3059 	    idev->cnf.accept_dad < 1 ||
3060 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3061 	    ifp->flags & IFA_F_NODAD) {
3062 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3063 		spin_unlock(&ifp->lock);
3064 		read_unlock_bh(&idev->lock);
3065 
3066 		addrconf_dad_completed(ifp);
3067 		return;
3068 	}
3069 
3070 	if (!(idev->if_flags & IF_READY)) {
3071 		spin_unlock(&ifp->lock);
3072 		read_unlock_bh(&idev->lock);
3073 		/*
3074 		 * If the device is not ready:
3075 		 * - keep it tentative if it is a permanent address.
3076 		 * - otherwise, kill it.
3077 		 */
3078 		in6_ifa_hold(ifp);
3079 		addrconf_dad_stop(ifp, 0);
3080 		return;
3081 	}
3082 
3083 	/*
3084 	 * Optimistic nodes can start receiving
3085 	 * Frames right away
3086 	 */
3087 	if (ifp->flags & IFA_F_OPTIMISTIC)
3088 		ip6_ins_rt(ifp->rt);
3089 
3090 	addrconf_dad_kick(ifp);
3091 out:
3092 	spin_unlock(&ifp->lock);
3093 	read_unlock_bh(&idev->lock);
3094 }
3095 
3096 static void addrconf_dad_timer(unsigned long data)
3097 {
3098 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *) data;
3099 	struct inet6_dev *idev = ifp->idev;
3100 	struct in6_addr mcaddr;
3101 
3102 	if (!ifp->probes && addrconf_dad_end(ifp))
3103 		goto out;
3104 
3105 	read_lock(&idev->lock);
3106 	if (idev->dead || !(idev->if_flags & IF_READY)) {
3107 		read_unlock(&idev->lock);
3108 		goto out;
3109 	}
3110 
3111 	spin_lock(&ifp->lock);
3112 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
3113 		spin_unlock(&ifp->lock);
3114 		read_unlock(&idev->lock);
3115 		goto out;
3116 	}
3117 
3118 	if (ifp->probes == 0) {
3119 		/*
3120 		 * DAD was successful
3121 		 */
3122 
3123 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3124 		spin_unlock(&ifp->lock);
3125 		read_unlock(&idev->lock);
3126 
3127 		addrconf_dad_completed(ifp);
3128 
3129 		goto out;
3130 	}
3131 
3132 	ifp->probes--;
3133 	addrconf_mod_timer(ifp, AC_DAD, ifp->idev->nd_parms->retrans_time);
3134 	spin_unlock(&ifp->lock);
3135 	read_unlock(&idev->lock);
3136 
3137 	/* send a neighbour solicitation for our addr */
3138 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
3139 	ndisc_send_ns(ifp->idev->dev, NULL, &ifp->addr, &mcaddr, &in6addr_any);
3140 out:
3141 	in6_ifa_put(ifp);
3142 }
3143 
3144 static void addrconf_dad_completed(struct inet6_ifaddr *ifp)
3145 {
3146 	struct net_device *dev = ifp->idev->dev;
3147 
3148 	/*
3149 	 *	Configure the address for reception. Now it is valid.
3150 	 */
3151 
3152 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
3153 
3154 	/* If added prefix is link local and we are prepared to process
3155 	   router advertisements, start sending router solicitations.
3156 	 */
3157 
3158 	if (ipv6_accept_ra(ifp->idev) &&
3159 	    ifp->idev->cnf.rtr_solicits > 0 &&
3160 	    (dev->flags&IFF_LOOPBACK) == 0 &&
3161 	    (ipv6_addr_type(&ifp->addr) & IPV6_ADDR_LINKLOCAL)) {
3162 		/*
3163 		 *	If a host as already performed a random delay
3164 		 *	[...] as part of DAD [...] there is no need
3165 		 *	to delay again before sending the first RS
3166 		 */
3167 		ndisc_send_rs(ifp->idev->dev, &ifp->addr, &in6addr_linklocal_allrouters);
3168 
3169 		spin_lock_bh(&ifp->lock);
3170 		ifp->probes = 1;
3171 		ifp->idev->if_flags |= IF_RS_SENT;
3172 		addrconf_mod_timer(ifp, AC_RS, ifp->idev->cnf.rtr_solicit_interval);
3173 		spin_unlock_bh(&ifp->lock);
3174 	}
3175 }
3176 
3177 static void addrconf_dad_run(struct inet6_dev *idev)
3178 {
3179 	struct inet6_ifaddr *ifp;
3180 
3181 	read_lock_bh(&idev->lock);
3182 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3183 		spin_lock(&ifp->lock);
3184 		if (ifp->flags & IFA_F_TENTATIVE &&
3185 		    ifp->state == INET6_IFADDR_STATE_DAD)
3186 			addrconf_dad_kick(ifp);
3187 		spin_unlock(&ifp->lock);
3188 	}
3189 	read_unlock_bh(&idev->lock);
3190 }
3191 
3192 #ifdef CONFIG_PROC_FS
3193 struct if6_iter_state {
3194 	struct seq_net_private p;
3195 	int bucket;
3196 	int offset;
3197 };
3198 
3199 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
3200 {
3201 	struct inet6_ifaddr *ifa = NULL;
3202 	struct if6_iter_state *state = seq->private;
3203 	struct net *net = seq_file_net(seq);
3204 	int p = 0;
3205 
3206 	/* initial bucket if pos is 0 */
3207 	if (pos == 0) {
3208 		state->bucket = 0;
3209 		state->offset = 0;
3210 	}
3211 
3212 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
3213 		struct hlist_node *n;
3214 		hlist_for_each_entry_rcu_bh(ifa, n, &inet6_addr_lst[state->bucket],
3215 					 addr_lst) {
3216 			if (!net_eq(dev_net(ifa->idev->dev), net))
3217 				continue;
3218 			/* sync with offset */
3219 			if (p < state->offset) {
3220 				p++;
3221 				continue;
3222 			}
3223 			state->offset++;
3224 			return ifa;
3225 		}
3226 
3227 		/* prepare for next bucket */
3228 		state->offset = 0;
3229 		p = 0;
3230 	}
3231 	return NULL;
3232 }
3233 
3234 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
3235 					 struct inet6_ifaddr *ifa)
3236 {
3237 	struct if6_iter_state *state = seq->private;
3238 	struct net *net = seq_file_net(seq);
3239 	struct hlist_node *n = &ifa->addr_lst;
3240 
3241 	hlist_for_each_entry_continue_rcu_bh(ifa, n, addr_lst) {
3242 		if (!net_eq(dev_net(ifa->idev->dev), net))
3243 			continue;
3244 		state->offset++;
3245 		return ifa;
3246 	}
3247 
3248 	while (++state->bucket < IN6_ADDR_HSIZE) {
3249 		state->offset = 0;
3250 		hlist_for_each_entry_rcu_bh(ifa, n,
3251 				     &inet6_addr_lst[state->bucket], addr_lst) {
3252 			if (!net_eq(dev_net(ifa->idev->dev), net))
3253 				continue;
3254 			state->offset++;
3255 			return ifa;
3256 		}
3257 	}
3258 
3259 	return NULL;
3260 }
3261 
3262 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
3263 	__acquires(rcu_bh)
3264 {
3265 	rcu_read_lock_bh();
3266 	return if6_get_first(seq, *pos);
3267 }
3268 
3269 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3270 {
3271 	struct inet6_ifaddr *ifa;
3272 
3273 	ifa = if6_get_next(seq, v);
3274 	++*pos;
3275 	return ifa;
3276 }
3277 
3278 static void if6_seq_stop(struct seq_file *seq, void *v)
3279 	__releases(rcu_bh)
3280 {
3281 	rcu_read_unlock_bh();
3282 }
3283 
3284 static int if6_seq_show(struct seq_file *seq, void *v)
3285 {
3286 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
3287 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
3288 		   &ifp->addr,
3289 		   ifp->idev->dev->ifindex,
3290 		   ifp->prefix_len,
3291 		   ifp->scope,
3292 		   ifp->flags,
3293 		   ifp->idev->dev->name);
3294 	return 0;
3295 }
3296 
3297 static const struct seq_operations if6_seq_ops = {
3298 	.start	= if6_seq_start,
3299 	.next	= if6_seq_next,
3300 	.show	= if6_seq_show,
3301 	.stop	= if6_seq_stop,
3302 };
3303 
3304 static int if6_seq_open(struct inode *inode, struct file *file)
3305 {
3306 	return seq_open_net(inode, file, &if6_seq_ops,
3307 			    sizeof(struct if6_iter_state));
3308 }
3309 
3310 static const struct file_operations if6_fops = {
3311 	.owner		= THIS_MODULE,
3312 	.open		= if6_seq_open,
3313 	.read		= seq_read,
3314 	.llseek		= seq_lseek,
3315 	.release	= seq_release_net,
3316 };
3317 
3318 static int __net_init if6_proc_net_init(struct net *net)
3319 {
3320 	if (!proc_net_fops_create(net, "if_inet6", S_IRUGO, &if6_fops))
3321 		return -ENOMEM;
3322 	return 0;
3323 }
3324 
3325 static void __net_exit if6_proc_net_exit(struct net *net)
3326 {
3327        proc_net_remove(net, "if_inet6");
3328 }
3329 
3330 static struct pernet_operations if6_proc_net_ops = {
3331        .init = if6_proc_net_init,
3332        .exit = if6_proc_net_exit,
3333 };
3334 
3335 int __init if6_proc_init(void)
3336 {
3337 	return register_pernet_subsys(&if6_proc_net_ops);
3338 }
3339 
3340 void if6_proc_exit(void)
3341 {
3342 	unregister_pernet_subsys(&if6_proc_net_ops);
3343 }
3344 #endif	/* CONFIG_PROC_FS */
3345 
3346 #if IS_ENABLED(CONFIG_IPV6_MIP6)
3347 /* Check if address is a home address configured on any interface. */
3348 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
3349 {
3350 	int ret = 0;
3351 	struct inet6_ifaddr *ifp = NULL;
3352 	struct hlist_node *n;
3353 	unsigned int hash = inet6_addr_hash(addr);
3354 
3355 	rcu_read_lock_bh();
3356 	hlist_for_each_entry_rcu_bh(ifp, n, &inet6_addr_lst[hash], addr_lst) {
3357 		if (!net_eq(dev_net(ifp->idev->dev), net))
3358 			continue;
3359 		if (ipv6_addr_equal(&ifp->addr, addr) &&
3360 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
3361 			ret = 1;
3362 			break;
3363 		}
3364 	}
3365 	rcu_read_unlock_bh();
3366 	return ret;
3367 }
3368 #endif
3369 
3370 /*
3371  *	Periodic address status verification
3372  */
3373 
3374 static void addrconf_verify(unsigned long foo)
3375 {
3376 	unsigned long now, next, next_sec, next_sched;
3377 	struct inet6_ifaddr *ifp;
3378 	struct hlist_node *node;
3379 	int i;
3380 
3381 	rcu_read_lock_bh();
3382 	spin_lock(&addrconf_verify_lock);
3383 	now = jiffies;
3384 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
3385 
3386 	del_timer(&addr_chk_timer);
3387 
3388 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3389 restart:
3390 		hlist_for_each_entry_rcu_bh(ifp, node,
3391 					 &inet6_addr_lst[i], addr_lst) {
3392 			unsigned long age;
3393 
3394 			if (ifp->flags & IFA_F_PERMANENT)
3395 				continue;
3396 
3397 			spin_lock(&ifp->lock);
3398 			/* We try to batch several events at once. */
3399 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
3400 
3401 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
3402 			    age >= ifp->valid_lft) {
3403 				spin_unlock(&ifp->lock);
3404 				in6_ifa_hold(ifp);
3405 				ipv6_del_addr(ifp);
3406 				goto restart;
3407 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
3408 				spin_unlock(&ifp->lock);
3409 				continue;
3410 			} else if (age >= ifp->prefered_lft) {
3411 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
3412 				int deprecate = 0;
3413 
3414 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
3415 					deprecate = 1;
3416 					ifp->flags |= IFA_F_DEPRECATED;
3417 				}
3418 
3419 				if (time_before(ifp->tstamp + ifp->valid_lft * HZ, next))
3420 					next = ifp->tstamp + ifp->valid_lft * HZ;
3421 
3422 				spin_unlock(&ifp->lock);
3423 
3424 				if (deprecate) {
3425 					in6_ifa_hold(ifp);
3426 
3427 					ipv6_ifa_notify(0, ifp);
3428 					in6_ifa_put(ifp);
3429 					goto restart;
3430 				}
3431 #ifdef CONFIG_IPV6_PRIVACY
3432 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
3433 				   !(ifp->flags&IFA_F_TENTATIVE)) {
3434 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
3435 					ifp->idev->cnf.dad_transmits *
3436 					ifp->idev->nd_parms->retrans_time / HZ;
3437 
3438 				if (age >= ifp->prefered_lft - regen_advance) {
3439 					struct inet6_ifaddr *ifpub = ifp->ifpub;
3440 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3441 						next = ifp->tstamp + ifp->prefered_lft * HZ;
3442 					if (!ifp->regen_count && ifpub) {
3443 						ifp->regen_count++;
3444 						in6_ifa_hold(ifp);
3445 						in6_ifa_hold(ifpub);
3446 						spin_unlock(&ifp->lock);
3447 
3448 						spin_lock(&ifpub->lock);
3449 						ifpub->regen_count = 0;
3450 						spin_unlock(&ifpub->lock);
3451 						ipv6_create_tempaddr(ifpub, ifp);
3452 						in6_ifa_put(ifpub);
3453 						in6_ifa_put(ifp);
3454 						goto restart;
3455 					}
3456 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
3457 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
3458 				spin_unlock(&ifp->lock);
3459 #endif
3460 			} else {
3461 				/* ifp->prefered_lft <= ifp->valid_lft */
3462 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
3463 					next = ifp->tstamp + ifp->prefered_lft * HZ;
3464 				spin_unlock(&ifp->lock);
3465 			}
3466 		}
3467 	}
3468 
3469 	next_sec = round_jiffies_up(next);
3470 	next_sched = next;
3471 
3472 	/* If rounded timeout is accurate enough, accept it. */
3473 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
3474 		next_sched = next_sec;
3475 
3476 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
3477 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
3478 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
3479 
3480 	ADBG((KERN_DEBUG "now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
3481 	      now, next, next_sec, next_sched));
3482 
3483 	addr_chk_timer.expires = next_sched;
3484 	add_timer(&addr_chk_timer);
3485 	spin_unlock(&addrconf_verify_lock);
3486 	rcu_read_unlock_bh();
3487 }
3488 
3489 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local)
3490 {
3491 	struct in6_addr *pfx = NULL;
3492 
3493 	if (addr)
3494 		pfx = nla_data(addr);
3495 
3496 	if (local) {
3497 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
3498 			pfx = NULL;
3499 		else
3500 			pfx = nla_data(local);
3501 	}
3502 
3503 	return pfx;
3504 }
3505 
3506 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
3507 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
3508 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
3509 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
3510 };
3511 
3512 static int
3513 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
3514 {
3515 	struct net *net = sock_net(skb->sk);
3516 	struct ifaddrmsg *ifm;
3517 	struct nlattr *tb[IFA_MAX+1];
3518 	struct in6_addr *pfx;
3519 	int err;
3520 
3521 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3522 	if (err < 0)
3523 		return err;
3524 
3525 	ifm = nlmsg_data(nlh);
3526 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL]);
3527 	if (pfx == NULL)
3528 		return -EINVAL;
3529 
3530 	return inet6_addr_del(net, ifm->ifa_index, pfx, ifm->ifa_prefixlen);
3531 }
3532 
3533 static int inet6_addr_modify(struct inet6_ifaddr *ifp, u8 ifa_flags,
3534 			     u32 prefered_lft, u32 valid_lft)
3535 {
3536 	u32 flags;
3537 	clock_t expires;
3538 	unsigned long timeout;
3539 
3540 	if (!valid_lft || (prefered_lft > valid_lft))
3541 		return -EINVAL;
3542 
3543 	timeout = addrconf_timeout_fixup(valid_lft, HZ);
3544 	if (addrconf_finite_timeout(timeout)) {
3545 		expires = jiffies_to_clock_t(timeout * HZ);
3546 		valid_lft = timeout;
3547 		flags = RTF_EXPIRES;
3548 	} else {
3549 		expires = 0;
3550 		flags = 0;
3551 		ifa_flags |= IFA_F_PERMANENT;
3552 	}
3553 
3554 	timeout = addrconf_timeout_fixup(prefered_lft, HZ);
3555 	if (addrconf_finite_timeout(timeout)) {
3556 		if (timeout == 0)
3557 			ifa_flags |= IFA_F_DEPRECATED;
3558 		prefered_lft = timeout;
3559 	}
3560 
3561 	spin_lock_bh(&ifp->lock);
3562 	ifp->flags = (ifp->flags & ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD | IFA_F_HOMEADDRESS)) | ifa_flags;
3563 	ifp->tstamp = jiffies;
3564 	ifp->valid_lft = valid_lft;
3565 	ifp->prefered_lft = prefered_lft;
3566 
3567 	spin_unlock_bh(&ifp->lock);
3568 	if (!(ifp->flags&IFA_F_TENTATIVE))
3569 		ipv6_ifa_notify(0, ifp);
3570 
3571 	addrconf_prefix_route(&ifp->addr, ifp->prefix_len, ifp->idev->dev,
3572 			      expires, flags);
3573 	addrconf_verify(0);
3574 
3575 	return 0;
3576 }
3577 
3578 static int
3579 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
3580 {
3581 	struct net *net = sock_net(skb->sk);
3582 	struct ifaddrmsg *ifm;
3583 	struct nlattr *tb[IFA_MAX+1];
3584 	struct in6_addr *pfx;
3585 	struct inet6_ifaddr *ifa;
3586 	struct net_device *dev;
3587 	u32 valid_lft = INFINITY_LIFE_TIME, preferred_lft = INFINITY_LIFE_TIME;
3588 	u8 ifa_flags;
3589 	int err;
3590 
3591 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3592 	if (err < 0)
3593 		return err;
3594 
3595 	ifm = nlmsg_data(nlh);
3596 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL]);
3597 	if (pfx == NULL)
3598 		return -EINVAL;
3599 
3600 	if (tb[IFA_CACHEINFO]) {
3601 		struct ifa_cacheinfo *ci;
3602 
3603 		ci = nla_data(tb[IFA_CACHEINFO]);
3604 		valid_lft = ci->ifa_valid;
3605 		preferred_lft = ci->ifa_prefered;
3606 	} else {
3607 		preferred_lft = INFINITY_LIFE_TIME;
3608 		valid_lft = INFINITY_LIFE_TIME;
3609 	}
3610 
3611 	dev =  __dev_get_by_index(net, ifm->ifa_index);
3612 	if (dev == NULL)
3613 		return -ENODEV;
3614 
3615 	/* We ignore other flags so far. */
3616 	ifa_flags = ifm->ifa_flags & (IFA_F_NODAD | IFA_F_HOMEADDRESS);
3617 
3618 	ifa = ipv6_get_ifaddr(net, pfx, dev, 1);
3619 	if (ifa == NULL) {
3620 		/*
3621 		 * It would be best to check for !NLM_F_CREATE here but
3622 		 * userspace alreay relies on not having to provide this.
3623 		 */
3624 		return inet6_addr_add(net, ifm->ifa_index, pfx,
3625 				      ifm->ifa_prefixlen, ifa_flags,
3626 				      preferred_lft, valid_lft);
3627 	}
3628 
3629 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
3630 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
3631 		err = -EEXIST;
3632 	else
3633 		err = inet6_addr_modify(ifa, ifa_flags, preferred_lft, valid_lft);
3634 
3635 	in6_ifa_put(ifa);
3636 
3637 	return err;
3638 }
3639 
3640 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u8 flags,
3641 			  u8 scope, int ifindex)
3642 {
3643 	struct ifaddrmsg *ifm;
3644 
3645 	ifm = nlmsg_data(nlh);
3646 	ifm->ifa_family = AF_INET6;
3647 	ifm->ifa_prefixlen = prefixlen;
3648 	ifm->ifa_flags = flags;
3649 	ifm->ifa_scope = scope;
3650 	ifm->ifa_index = ifindex;
3651 }
3652 
3653 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
3654 			 unsigned long tstamp, u32 preferred, u32 valid)
3655 {
3656 	struct ifa_cacheinfo ci;
3657 
3658 	ci.cstamp = cstamp_delta(cstamp);
3659 	ci.tstamp = cstamp_delta(tstamp);
3660 	ci.ifa_prefered = preferred;
3661 	ci.ifa_valid = valid;
3662 
3663 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
3664 }
3665 
3666 static inline int rt_scope(int ifa_scope)
3667 {
3668 	if (ifa_scope & IFA_HOST)
3669 		return RT_SCOPE_HOST;
3670 	else if (ifa_scope & IFA_LINK)
3671 		return RT_SCOPE_LINK;
3672 	else if (ifa_scope & IFA_SITE)
3673 		return RT_SCOPE_SITE;
3674 	else
3675 		return RT_SCOPE_UNIVERSE;
3676 }
3677 
3678 static inline int inet6_ifaddr_msgsize(void)
3679 {
3680 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
3681 	       + nla_total_size(16) /* IFA_ADDRESS */
3682 	       + nla_total_size(sizeof(struct ifa_cacheinfo));
3683 }
3684 
3685 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
3686 			     u32 portid, u32 seq, int event, unsigned int flags)
3687 {
3688 	struct nlmsghdr  *nlh;
3689 	u32 preferred, valid;
3690 
3691 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
3692 	if (nlh == NULL)
3693 		return -EMSGSIZE;
3694 
3695 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
3696 		      ifa->idev->dev->ifindex);
3697 
3698 	if (!(ifa->flags&IFA_F_PERMANENT)) {
3699 		preferred = ifa->prefered_lft;
3700 		valid = ifa->valid_lft;
3701 		if (preferred != INFINITY_LIFE_TIME) {
3702 			long tval = (jiffies - ifa->tstamp)/HZ;
3703 			if (preferred > tval)
3704 				preferred -= tval;
3705 			else
3706 				preferred = 0;
3707 			if (valid != INFINITY_LIFE_TIME) {
3708 				if (valid > tval)
3709 					valid -= tval;
3710 				else
3711 					valid = 0;
3712 			}
3713 		}
3714 	} else {
3715 		preferred = INFINITY_LIFE_TIME;
3716 		valid = INFINITY_LIFE_TIME;
3717 	}
3718 
3719 	if (nla_put(skb, IFA_ADDRESS, 16, &ifa->addr) < 0 ||
3720 	    put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0) {
3721 		nlmsg_cancel(skb, nlh);
3722 		return -EMSGSIZE;
3723 	}
3724 
3725 	return nlmsg_end(skb, nlh);
3726 }
3727 
3728 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
3729 				u32 portid, u32 seq, int event, u16 flags)
3730 {
3731 	struct nlmsghdr  *nlh;
3732 	u8 scope = RT_SCOPE_UNIVERSE;
3733 	int ifindex = ifmca->idev->dev->ifindex;
3734 
3735 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
3736 		scope = RT_SCOPE_SITE;
3737 
3738 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
3739 	if (nlh == NULL)
3740 		return -EMSGSIZE;
3741 
3742 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
3743 	if (nla_put(skb, IFA_MULTICAST, 16, &ifmca->mca_addr) < 0 ||
3744 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
3745 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
3746 		nlmsg_cancel(skb, nlh);
3747 		return -EMSGSIZE;
3748 	}
3749 
3750 	return nlmsg_end(skb, nlh);
3751 }
3752 
3753 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
3754 				u32 portid, u32 seq, int event, unsigned int flags)
3755 {
3756 	struct nlmsghdr  *nlh;
3757 	u8 scope = RT_SCOPE_UNIVERSE;
3758 	int ifindex = ifaca->aca_idev->dev->ifindex;
3759 
3760 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
3761 		scope = RT_SCOPE_SITE;
3762 
3763 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct ifaddrmsg), flags);
3764 	if (nlh == NULL)
3765 		return -EMSGSIZE;
3766 
3767 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
3768 	if (nla_put(skb, IFA_ANYCAST, 16, &ifaca->aca_addr) < 0 ||
3769 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
3770 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
3771 		nlmsg_cancel(skb, nlh);
3772 		return -EMSGSIZE;
3773 	}
3774 
3775 	return nlmsg_end(skb, nlh);
3776 }
3777 
3778 enum addr_type_t {
3779 	UNICAST_ADDR,
3780 	MULTICAST_ADDR,
3781 	ANYCAST_ADDR,
3782 };
3783 
3784 /* called with rcu_read_lock() */
3785 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
3786 			  struct netlink_callback *cb, enum addr_type_t type,
3787 			  int s_ip_idx, int *p_ip_idx)
3788 {
3789 	struct ifmcaddr6 *ifmca;
3790 	struct ifacaddr6 *ifaca;
3791 	int err = 1;
3792 	int ip_idx = *p_ip_idx;
3793 
3794 	read_lock_bh(&idev->lock);
3795 	switch (type) {
3796 	case UNICAST_ADDR: {
3797 		struct inet6_ifaddr *ifa;
3798 
3799 		/* unicast address incl. temp addr */
3800 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
3801 			if (++ip_idx < s_ip_idx)
3802 				continue;
3803 			err = inet6_fill_ifaddr(skb, ifa,
3804 						NETLINK_CB(cb->skb).portid,
3805 						cb->nlh->nlmsg_seq,
3806 						RTM_NEWADDR,
3807 						NLM_F_MULTI);
3808 			if (err <= 0)
3809 				break;
3810 		}
3811 		break;
3812 	}
3813 	case MULTICAST_ADDR:
3814 		/* multicast address */
3815 		for (ifmca = idev->mc_list; ifmca;
3816 		     ifmca = ifmca->next, ip_idx++) {
3817 			if (ip_idx < s_ip_idx)
3818 				continue;
3819 			err = inet6_fill_ifmcaddr(skb, ifmca,
3820 						  NETLINK_CB(cb->skb).portid,
3821 						  cb->nlh->nlmsg_seq,
3822 						  RTM_GETMULTICAST,
3823 						  NLM_F_MULTI);
3824 			if (err <= 0)
3825 				break;
3826 		}
3827 		break;
3828 	case ANYCAST_ADDR:
3829 		/* anycast address */
3830 		for (ifaca = idev->ac_list; ifaca;
3831 		     ifaca = ifaca->aca_next, ip_idx++) {
3832 			if (ip_idx < s_ip_idx)
3833 				continue;
3834 			err = inet6_fill_ifacaddr(skb, ifaca,
3835 						  NETLINK_CB(cb->skb).portid,
3836 						  cb->nlh->nlmsg_seq,
3837 						  RTM_GETANYCAST,
3838 						  NLM_F_MULTI);
3839 			if (err <= 0)
3840 				break;
3841 		}
3842 		break;
3843 	default:
3844 		break;
3845 	}
3846 	read_unlock_bh(&idev->lock);
3847 	*p_ip_idx = ip_idx;
3848 	return err;
3849 }
3850 
3851 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
3852 			   enum addr_type_t type)
3853 {
3854 	struct net *net = sock_net(skb->sk);
3855 	int h, s_h;
3856 	int idx, ip_idx;
3857 	int s_idx, s_ip_idx;
3858 	struct net_device *dev;
3859 	struct inet6_dev *idev;
3860 	struct hlist_head *head;
3861 	struct hlist_node *node;
3862 
3863 	s_h = cb->args[0];
3864 	s_idx = idx = cb->args[1];
3865 	s_ip_idx = ip_idx = cb->args[2];
3866 
3867 	rcu_read_lock();
3868 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
3869 		idx = 0;
3870 		head = &net->dev_index_head[h];
3871 		hlist_for_each_entry_rcu(dev, node, head, index_hlist) {
3872 			if (idx < s_idx)
3873 				goto cont;
3874 			if (h > s_h || idx > s_idx)
3875 				s_ip_idx = 0;
3876 			ip_idx = 0;
3877 			idev = __in6_dev_get(dev);
3878 			if (!idev)
3879 				goto cont;
3880 
3881 			if (in6_dump_addrs(idev, skb, cb, type,
3882 					   s_ip_idx, &ip_idx) <= 0)
3883 				goto done;
3884 cont:
3885 			idx++;
3886 		}
3887 	}
3888 done:
3889 	rcu_read_unlock();
3890 	cb->args[0] = h;
3891 	cb->args[1] = idx;
3892 	cb->args[2] = ip_idx;
3893 
3894 	return skb->len;
3895 }
3896 
3897 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
3898 {
3899 	enum addr_type_t type = UNICAST_ADDR;
3900 
3901 	return inet6_dump_addr(skb, cb, type);
3902 }
3903 
3904 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
3905 {
3906 	enum addr_type_t type = MULTICAST_ADDR;
3907 
3908 	return inet6_dump_addr(skb, cb, type);
3909 }
3910 
3911 
3912 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
3913 {
3914 	enum addr_type_t type = ANYCAST_ADDR;
3915 
3916 	return inet6_dump_addr(skb, cb, type);
3917 }
3918 
3919 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
3920 			     void *arg)
3921 {
3922 	struct net *net = sock_net(in_skb->sk);
3923 	struct ifaddrmsg *ifm;
3924 	struct nlattr *tb[IFA_MAX+1];
3925 	struct in6_addr *addr = NULL;
3926 	struct net_device *dev = NULL;
3927 	struct inet6_ifaddr *ifa;
3928 	struct sk_buff *skb;
3929 	int err;
3930 
3931 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy);
3932 	if (err < 0)
3933 		goto errout;
3934 
3935 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL]);
3936 	if (addr == NULL) {
3937 		err = -EINVAL;
3938 		goto errout;
3939 	}
3940 
3941 	ifm = nlmsg_data(nlh);
3942 	if (ifm->ifa_index)
3943 		dev = __dev_get_by_index(net, ifm->ifa_index);
3944 
3945 	ifa = ipv6_get_ifaddr(net, addr, dev, 1);
3946 	if (!ifa) {
3947 		err = -EADDRNOTAVAIL;
3948 		goto errout;
3949 	}
3950 
3951 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
3952 	if (!skb) {
3953 		err = -ENOBUFS;
3954 		goto errout_ifa;
3955 	}
3956 
3957 	err = inet6_fill_ifaddr(skb, ifa, NETLINK_CB(in_skb).portid,
3958 				nlh->nlmsg_seq, RTM_NEWADDR, 0);
3959 	if (err < 0) {
3960 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
3961 		WARN_ON(err == -EMSGSIZE);
3962 		kfree_skb(skb);
3963 		goto errout_ifa;
3964 	}
3965 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
3966 errout_ifa:
3967 	in6_ifa_put(ifa);
3968 errout:
3969 	return err;
3970 }
3971 
3972 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
3973 {
3974 	struct sk_buff *skb;
3975 	struct net *net = dev_net(ifa->idev->dev);
3976 	int err = -ENOBUFS;
3977 
3978 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
3979 	if (skb == NULL)
3980 		goto errout;
3981 
3982 	err = inet6_fill_ifaddr(skb, ifa, 0, 0, event, 0);
3983 	if (err < 0) {
3984 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
3985 		WARN_ON(err == -EMSGSIZE);
3986 		kfree_skb(skb);
3987 		goto errout;
3988 	}
3989 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
3990 	return;
3991 errout:
3992 	if (err < 0)
3993 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
3994 }
3995 
3996 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
3997 				__s32 *array, int bytes)
3998 {
3999 	BUG_ON(bytes < (DEVCONF_MAX * 4));
4000 
4001 	memset(array, 0, bytes);
4002 	array[DEVCONF_FORWARDING] = cnf->forwarding;
4003 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
4004 	array[DEVCONF_MTU6] = cnf->mtu6;
4005 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
4006 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
4007 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
4008 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
4009 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
4010 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
4011 		jiffies_to_msecs(cnf->rtr_solicit_interval);
4012 	array[DEVCONF_RTR_SOLICIT_DELAY] =
4013 		jiffies_to_msecs(cnf->rtr_solicit_delay);
4014 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
4015 #ifdef CONFIG_IPV6_PRIVACY
4016 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
4017 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
4018 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
4019 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
4020 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
4021 #endif
4022 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
4023 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
4024 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
4025 #ifdef CONFIG_IPV6_ROUTER_PREF
4026 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
4027 	array[DEVCONF_RTR_PROBE_INTERVAL] =
4028 		jiffies_to_msecs(cnf->rtr_probe_interval);
4029 #ifdef CONFIG_IPV6_ROUTE_INFO
4030 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
4031 #endif
4032 #endif
4033 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
4034 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
4035 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
4036 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
4037 #endif
4038 #ifdef CONFIG_IPV6_MROUTE
4039 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
4040 #endif
4041 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
4042 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
4043 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
4044 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
4045 }
4046 
4047 static inline size_t inet6_ifla6_size(void)
4048 {
4049 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
4050 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
4051 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
4052 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
4053 	     + nla_total_size(ICMP6_MIB_MAX * 8); /* IFLA_INET6_ICMP6STATS */
4054 }
4055 
4056 static inline size_t inet6_if_nlmsg_size(void)
4057 {
4058 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
4059 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
4060 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
4061 	       + nla_total_size(4) /* IFLA_MTU */
4062 	       + nla_total_size(4) /* IFLA_LINK */
4063 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
4064 }
4065 
4066 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
4067 				      int items, int bytes)
4068 {
4069 	int i;
4070 	int pad = bytes - sizeof(u64) * items;
4071 	BUG_ON(pad < 0);
4072 
4073 	/* Use put_unaligned() because stats may not be aligned for u64. */
4074 	put_unaligned(items, &stats[0]);
4075 	for (i = 1; i < items; i++)
4076 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
4077 
4078 	memset(&stats[items], 0, pad);
4079 }
4080 
4081 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu **mib,
4082 				      int items, int bytes, size_t syncpoff)
4083 {
4084 	int i;
4085 	int pad = bytes - sizeof(u64) * items;
4086 	BUG_ON(pad < 0);
4087 
4088 	/* Use put_unaligned() because stats may not be aligned for u64. */
4089 	put_unaligned(items, &stats[0]);
4090 	for (i = 1; i < items; i++)
4091 		put_unaligned(snmp_fold_field64(mib, i, syncpoff), &stats[i]);
4092 
4093 	memset(&stats[items], 0, pad);
4094 }
4095 
4096 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
4097 			     int bytes)
4098 {
4099 	switch (attrtype) {
4100 	case IFLA_INET6_STATS:
4101 		__snmp6_fill_stats64(stats, (void __percpu **)idev->stats.ipv6,
4102 				     IPSTATS_MIB_MAX, bytes, offsetof(struct ipstats_mib, syncp));
4103 		break;
4104 	case IFLA_INET6_ICMP6STATS:
4105 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, ICMP6_MIB_MAX, bytes);
4106 		break;
4107 	}
4108 }
4109 
4110 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev)
4111 {
4112 	struct nlattr *nla;
4113 	struct ifla_cacheinfo ci;
4114 
4115 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
4116 		goto nla_put_failure;
4117 	ci.max_reasm_len = IPV6_MAXPLEN;
4118 	ci.tstamp = cstamp_delta(idev->tstamp);
4119 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
4120 	ci.retrans_time = jiffies_to_msecs(idev->nd_parms->retrans_time);
4121 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
4122 		goto nla_put_failure;
4123 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
4124 	if (nla == NULL)
4125 		goto nla_put_failure;
4126 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
4127 
4128 	/* XXX - MC not implemented */
4129 
4130 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
4131 	if (nla == NULL)
4132 		goto nla_put_failure;
4133 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
4134 
4135 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
4136 	if (nla == NULL)
4137 		goto nla_put_failure;
4138 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
4139 
4140 	return 0;
4141 
4142 nla_put_failure:
4143 	return -EMSGSIZE;
4144 }
4145 
4146 static size_t inet6_get_link_af_size(const struct net_device *dev)
4147 {
4148 	if (!__in6_dev_get(dev))
4149 		return 0;
4150 
4151 	return inet6_ifla6_size();
4152 }
4153 
4154 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev)
4155 {
4156 	struct inet6_dev *idev = __in6_dev_get(dev);
4157 
4158 	if (!idev)
4159 		return -ENODATA;
4160 
4161 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
4162 		return -EMSGSIZE;
4163 
4164 	return 0;
4165 }
4166 
4167 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
4168 			     u32 portid, u32 seq, int event, unsigned int flags)
4169 {
4170 	struct net_device *dev = idev->dev;
4171 	struct ifinfomsg *hdr;
4172 	struct nlmsghdr *nlh;
4173 	void *protoinfo;
4174 
4175 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
4176 	if (nlh == NULL)
4177 		return -EMSGSIZE;
4178 
4179 	hdr = nlmsg_data(nlh);
4180 	hdr->ifi_family = AF_INET6;
4181 	hdr->__ifi_pad = 0;
4182 	hdr->ifi_type = dev->type;
4183 	hdr->ifi_index = dev->ifindex;
4184 	hdr->ifi_flags = dev_get_flags(dev);
4185 	hdr->ifi_change = 0;
4186 
4187 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
4188 	    (dev->addr_len &&
4189 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
4190 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
4191 	    (dev->ifindex != dev->iflink &&
4192 	     nla_put_u32(skb, IFLA_LINK, dev->iflink)))
4193 		goto nla_put_failure;
4194 	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
4195 	if (protoinfo == NULL)
4196 		goto nla_put_failure;
4197 
4198 	if (inet6_fill_ifla6_attrs(skb, idev) < 0)
4199 		goto nla_put_failure;
4200 
4201 	nla_nest_end(skb, protoinfo);
4202 	return nlmsg_end(skb, nlh);
4203 
4204 nla_put_failure:
4205 	nlmsg_cancel(skb, nlh);
4206 	return -EMSGSIZE;
4207 }
4208 
4209 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
4210 {
4211 	struct net *net = sock_net(skb->sk);
4212 	int h, s_h;
4213 	int idx = 0, s_idx;
4214 	struct net_device *dev;
4215 	struct inet6_dev *idev;
4216 	struct hlist_head *head;
4217 	struct hlist_node *node;
4218 
4219 	s_h = cb->args[0];
4220 	s_idx = cb->args[1];
4221 
4222 	rcu_read_lock();
4223 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
4224 		idx = 0;
4225 		head = &net->dev_index_head[h];
4226 		hlist_for_each_entry_rcu(dev, node, head, index_hlist) {
4227 			if (idx < s_idx)
4228 				goto cont;
4229 			idev = __in6_dev_get(dev);
4230 			if (!idev)
4231 				goto cont;
4232 			if (inet6_fill_ifinfo(skb, idev,
4233 					      NETLINK_CB(cb->skb).portid,
4234 					      cb->nlh->nlmsg_seq,
4235 					      RTM_NEWLINK, NLM_F_MULTI) <= 0)
4236 				goto out;
4237 cont:
4238 			idx++;
4239 		}
4240 	}
4241 out:
4242 	rcu_read_unlock();
4243 	cb->args[1] = idx;
4244 	cb->args[0] = h;
4245 
4246 	return skb->len;
4247 }
4248 
4249 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
4250 {
4251 	struct sk_buff *skb;
4252 	struct net *net = dev_net(idev->dev);
4253 	int err = -ENOBUFS;
4254 
4255 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
4256 	if (skb == NULL)
4257 		goto errout;
4258 
4259 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
4260 	if (err < 0) {
4261 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
4262 		WARN_ON(err == -EMSGSIZE);
4263 		kfree_skb(skb);
4264 		goto errout;
4265 	}
4266 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
4267 	return;
4268 errout:
4269 	if (err < 0)
4270 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
4271 }
4272 
4273 static inline size_t inet6_prefix_nlmsg_size(void)
4274 {
4275 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
4276 	       + nla_total_size(sizeof(struct in6_addr))
4277 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
4278 }
4279 
4280 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
4281 			     struct prefix_info *pinfo, u32 portid, u32 seq,
4282 			     int event, unsigned int flags)
4283 {
4284 	struct prefixmsg *pmsg;
4285 	struct nlmsghdr *nlh;
4286 	struct prefix_cacheinfo	ci;
4287 
4288 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
4289 	if (nlh == NULL)
4290 		return -EMSGSIZE;
4291 
4292 	pmsg = nlmsg_data(nlh);
4293 	pmsg->prefix_family = AF_INET6;
4294 	pmsg->prefix_pad1 = 0;
4295 	pmsg->prefix_pad2 = 0;
4296 	pmsg->prefix_ifindex = idev->dev->ifindex;
4297 	pmsg->prefix_len = pinfo->prefix_len;
4298 	pmsg->prefix_type = pinfo->type;
4299 	pmsg->prefix_pad3 = 0;
4300 	pmsg->prefix_flags = 0;
4301 	if (pinfo->onlink)
4302 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
4303 	if (pinfo->autoconf)
4304 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
4305 
4306 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
4307 		goto nla_put_failure;
4308 	ci.preferred_time = ntohl(pinfo->prefered);
4309 	ci.valid_time = ntohl(pinfo->valid);
4310 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
4311 		goto nla_put_failure;
4312 	return nlmsg_end(skb, nlh);
4313 
4314 nla_put_failure:
4315 	nlmsg_cancel(skb, nlh);
4316 	return -EMSGSIZE;
4317 }
4318 
4319 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
4320 			 struct prefix_info *pinfo)
4321 {
4322 	struct sk_buff *skb;
4323 	struct net *net = dev_net(idev->dev);
4324 	int err = -ENOBUFS;
4325 
4326 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
4327 	if (skb == NULL)
4328 		goto errout;
4329 
4330 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
4331 	if (err < 0) {
4332 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
4333 		WARN_ON(err == -EMSGSIZE);
4334 		kfree_skb(skb);
4335 		goto errout;
4336 	}
4337 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
4338 	return;
4339 errout:
4340 	if (err < 0)
4341 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
4342 }
4343 
4344 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
4345 {
4346 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
4347 
4348 	switch (event) {
4349 	case RTM_NEWADDR:
4350 		/*
4351 		 * If the address was optimistic
4352 		 * we inserted the route at the start of
4353 		 * our DAD process, so we don't need
4354 		 * to do it again
4355 		 */
4356 		if (!(ifp->rt->rt6i_node))
4357 			ip6_ins_rt(ifp->rt);
4358 		if (ifp->idev->cnf.forwarding)
4359 			addrconf_join_anycast(ifp);
4360 		break;
4361 	case RTM_DELADDR:
4362 		if (ifp->idev->cnf.forwarding)
4363 			addrconf_leave_anycast(ifp);
4364 		addrconf_leave_solict(ifp->idev, &ifp->addr);
4365 		dst_hold(&ifp->rt->dst);
4366 
4367 		if (ip6_del_rt(ifp->rt))
4368 			dst_free(&ifp->rt->dst);
4369 		break;
4370 	}
4371 }
4372 
4373 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
4374 {
4375 	rcu_read_lock_bh();
4376 	if (likely(ifp->idev->dead == 0))
4377 		__ipv6_ifa_notify(event, ifp);
4378 	rcu_read_unlock_bh();
4379 }
4380 
4381 #ifdef CONFIG_SYSCTL
4382 
4383 static
4384 int addrconf_sysctl_forward(ctl_table *ctl, int write,
4385 			   void __user *buffer, size_t *lenp, loff_t *ppos)
4386 {
4387 	int *valp = ctl->data;
4388 	int val = *valp;
4389 	loff_t pos = *ppos;
4390 	ctl_table lctl;
4391 	int ret;
4392 
4393 	/*
4394 	 * ctl->data points to idev->cnf.forwarding, we should
4395 	 * not modify it until we get the rtnl lock.
4396 	 */
4397 	lctl = *ctl;
4398 	lctl.data = &val;
4399 
4400 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
4401 
4402 	if (write)
4403 		ret = addrconf_fixup_forwarding(ctl, valp, val);
4404 	if (ret)
4405 		*ppos = pos;
4406 	return ret;
4407 }
4408 
4409 static void dev_disable_change(struct inet6_dev *idev)
4410 {
4411 	if (!idev || !idev->dev)
4412 		return;
4413 
4414 	if (idev->cnf.disable_ipv6)
4415 		addrconf_notify(NULL, NETDEV_DOWN, idev->dev);
4416 	else
4417 		addrconf_notify(NULL, NETDEV_UP, idev->dev);
4418 }
4419 
4420 static void addrconf_disable_change(struct net *net, __s32 newf)
4421 {
4422 	struct net_device *dev;
4423 	struct inet6_dev *idev;
4424 
4425 	rcu_read_lock();
4426 	for_each_netdev_rcu(net, dev) {
4427 		idev = __in6_dev_get(dev);
4428 		if (idev) {
4429 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
4430 			idev->cnf.disable_ipv6 = newf;
4431 			if (changed)
4432 				dev_disable_change(idev);
4433 		}
4434 	}
4435 	rcu_read_unlock();
4436 }
4437 
4438 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
4439 {
4440 	struct net *net;
4441 	int old;
4442 
4443 	if (!rtnl_trylock())
4444 		return restart_syscall();
4445 
4446 	net = (struct net *)table->extra2;
4447 	old = *p;
4448 	*p = newf;
4449 
4450 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
4451 		rtnl_unlock();
4452 		return 0;
4453 	}
4454 
4455 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
4456 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
4457 		addrconf_disable_change(net, newf);
4458 	} else if ((!newf) ^ (!old))
4459 		dev_disable_change((struct inet6_dev *)table->extra1);
4460 
4461 	rtnl_unlock();
4462 	return 0;
4463 }
4464 
4465 static
4466 int addrconf_sysctl_disable(ctl_table *ctl, int write,
4467 			    void __user *buffer, size_t *lenp, loff_t *ppos)
4468 {
4469 	int *valp = ctl->data;
4470 	int val = *valp;
4471 	loff_t pos = *ppos;
4472 	ctl_table lctl;
4473 	int ret;
4474 
4475 	/*
4476 	 * ctl->data points to idev->cnf.disable_ipv6, we should
4477 	 * not modify it until we get the rtnl lock.
4478 	 */
4479 	lctl = *ctl;
4480 	lctl.data = &val;
4481 
4482 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
4483 
4484 	if (write)
4485 		ret = addrconf_disable_ipv6(ctl, valp, val);
4486 	if (ret)
4487 		*ppos = pos;
4488 	return ret;
4489 }
4490 
4491 static struct addrconf_sysctl_table
4492 {
4493 	struct ctl_table_header *sysctl_header;
4494 	ctl_table addrconf_vars[DEVCONF_MAX+1];
4495 } addrconf_sysctl __read_mostly = {
4496 	.sysctl_header = NULL,
4497 	.addrconf_vars = {
4498 		{
4499 			.procname	= "forwarding",
4500 			.data		= &ipv6_devconf.forwarding,
4501 			.maxlen		= sizeof(int),
4502 			.mode		= 0644,
4503 			.proc_handler	= addrconf_sysctl_forward,
4504 		},
4505 		{
4506 			.procname	= "hop_limit",
4507 			.data		= &ipv6_devconf.hop_limit,
4508 			.maxlen		= sizeof(int),
4509 			.mode		= 0644,
4510 			.proc_handler	= proc_dointvec,
4511 		},
4512 		{
4513 			.procname	= "mtu",
4514 			.data		= &ipv6_devconf.mtu6,
4515 			.maxlen		= sizeof(int),
4516 			.mode		= 0644,
4517 			.proc_handler	= proc_dointvec,
4518 		},
4519 		{
4520 			.procname	= "accept_ra",
4521 			.data		= &ipv6_devconf.accept_ra,
4522 			.maxlen		= sizeof(int),
4523 			.mode		= 0644,
4524 			.proc_handler	= proc_dointvec,
4525 		},
4526 		{
4527 			.procname	= "accept_redirects",
4528 			.data		= &ipv6_devconf.accept_redirects,
4529 			.maxlen		= sizeof(int),
4530 			.mode		= 0644,
4531 			.proc_handler	= proc_dointvec,
4532 		},
4533 		{
4534 			.procname	= "autoconf",
4535 			.data		= &ipv6_devconf.autoconf,
4536 			.maxlen		= sizeof(int),
4537 			.mode		= 0644,
4538 			.proc_handler	= proc_dointvec,
4539 		},
4540 		{
4541 			.procname	= "dad_transmits",
4542 			.data		= &ipv6_devconf.dad_transmits,
4543 			.maxlen		= sizeof(int),
4544 			.mode		= 0644,
4545 			.proc_handler	= proc_dointvec,
4546 		},
4547 		{
4548 			.procname	= "router_solicitations",
4549 			.data		= &ipv6_devconf.rtr_solicits,
4550 			.maxlen		= sizeof(int),
4551 			.mode		= 0644,
4552 			.proc_handler	= proc_dointvec,
4553 		},
4554 		{
4555 			.procname	= "router_solicitation_interval",
4556 			.data		= &ipv6_devconf.rtr_solicit_interval,
4557 			.maxlen		= sizeof(int),
4558 			.mode		= 0644,
4559 			.proc_handler	= proc_dointvec_jiffies,
4560 		},
4561 		{
4562 			.procname	= "router_solicitation_delay",
4563 			.data		= &ipv6_devconf.rtr_solicit_delay,
4564 			.maxlen		= sizeof(int),
4565 			.mode		= 0644,
4566 			.proc_handler	= proc_dointvec_jiffies,
4567 		},
4568 		{
4569 			.procname	= "force_mld_version",
4570 			.data		= &ipv6_devconf.force_mld_version,
4571 			.maxlen		= sizeof(int),
4572 			.mode		= 0644,
4573 			.proc_handler	= proc_dointvec,
4574 		},
4575 #ifdef CONFIG_IPV6_PRIVACY
4576 		{
4577 			.procname	= "use_tempaddr",
4578 			.data		= &ipv6_devconf.use_tempaddr,
4579 			.maxlen		= sizeof(int),
4580 			.mode		= 0644,
4581 			.proc_handler	= proc_dointvec,
4582 		},
4583 		{
4584 			.procname	= "temp_valid_lft",
4585 			.data		= &ipv6_devconf.temp_valid_lft,
4586 			.maxlen		= sizeof(int),
4587 			.mode		= 0644,
4588 			.proc_handler	= proc_dointvec,
4589 		},
4590 		{
4591 			.procname	= "temp_prefered_lft",
4592 			.data		= &ipv6_devconf.temp_prefered_lft,
4593 			.maxlen		= sizeof(int),
4594 			.mode		= 0644,
4595 			.proc_handler	= proc_dointvec,
4596 		},
4597 		{
4598 			.procname	= "regen_max_retry",
4599 			.data		= &ipv6_devconf.regen_max_retry,
4600 			.maxlen		= sizeof(int),
4601 			.mode		= 0644,
4602 			.proc_handler	= proc_dointvec,
4603 		},
4604 		{
4605 			.procname	= "max_desync_factor",
4606 			.data		= &ipv6_devconf.max_desync_factor,
4607 			.maxlen		= sizeof(int),
4608 			.mode		= 0644,
4609 			.proc_handler	= proc_dointvec,
4610 		},
4611 #endif
4612 		{
4613 			.procname	= "max_addresses",
4614 			.data		= &ipv6_devconf.max_addresses,
4615 			.maxlen		= sizeof(int),
4616 			.mode		= 0644,
4617 			.proc_handler	= proc_dointvec,
4618 		},
4619 		{
4620 			.procname	= "accept_ra_defrtr",
4621 			.data		= &ipv6_devconf.accept_ra_defrtr,
4622 			.maxlen		= sizeof(int),
4623 			.mode		= 0644,
4624 			.proc_handler	= proc_dointvec,
4625 		},
4626 		{
4627 			.procname	= "accept_ra_pinfo",
4628 			.data		= &ipv6_devconf.accept_ra_pinfo,
4629 			.maxlen		= sizeof(int),
4630 			.mode		= 0644,
4631 			.proc_handler	= proc_dointvec,
4632 		},
4633 #ifdef CONFIG_IPV6_ROUTER_PREF
4634 		{
4635 			.procname	= "accept_ra_rtr_pref",
4636 			.data		= &ipv6_devconf.accept_ra_rtr_pref,
4637 			.maxlen		= sizeof(int),
4638 			.mode		= 0644,
4639 			.proc_handler	= proc_dointvec,
4640 		},
4641 		{
4642 			.procname	= "router_probe_interval",
4643 			.data		= &ipv6_devconf.rtr_probe_interval,
4644 			.maxlen		= sizeof(int),
4645 			.mode		= 0644,
4646 			.proc_handler	= proc_dointvec_jiffies,
4647 		},
4648 #ifdef CONFIG_IPV6_ROUTE_INFO
4649 		{
4650 			.procname	= "accept_ra_rt_info_max_plen",
4651 			.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
4652 			.maxlen		= sizeof(int),
4653 			.mode		= 0644,
4654 			.proc_handler	= proc_dointvec,
4655 		},
4656 #endif
4657 #endif
4658 		{
4659 			.procname	= "proxy_ndp",
4660 			.data		= &ipv6_devconf.proxy_ndp,
4661 			.maxlen		= sizeof(int),
4662 			.mode		= 0644,
4663 			.proc_handler	= proc_dointvec,
4664 		},
4665 		{
4666 			.procname	= "accept_source_route",
4667 			.data		= &ipv6_devconf.accept_source_route,
4668 			.maxlen		= sizeof(int),
4669 			.mode		= 0644,
4670 			.proc_handler	= proc_dointvec,
4671 		},
4672 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
4673 		{
4674 			.procname       = "optimistic_dad",
4675 			.data           = &ipv6_devconf.optimistic_dad,
4676 			.maxlen         = sizeof(int),
4677 			.mode           = 0644,
4678 			.proc_handler   = proc_dointvec,
4679 
4680 		},
4681 #endif
4682 #ifdef CONFIG_IPV6_MROUTE
4683 		{
4684 			.procname	= "mc_forwarding",
4685 			.data		= &ipv6_devconf.mc_forwarding,
4686 			.maxlen		= sizeof(int),
4687 			.mode		= 0444,
4688 			.proc_handler	= proc_dointvec,
4689 		},
4690 #endif
4691 		{
4692 			.procname	= "disable_ipv6",
4693 			.data		= &ipv6_devconf.disable_ipv6,
4694 			.maxlen		= sizeof(int),
4695 			.mode		= 0644,
4696 			.proc_handler	= addrconf_sysctl_disable,
4697 		},
4698 		{
4699 			.procname	= "accept_dad",
4700 			.data		= &ipv6_devconf.accept_dad,
4701 			.maxlen		= sizeof(int),
4702 			.mode		= 0644,
4703 			.proc_handler	= proc_dointvec,
4704 		},
4705 		{
4706 			.procname       = "force_tllao",
4707 			.data           = &ipv6_devconf.force_tllao,
4708 			.maxlen         = sizeof(int),
4709 			.mode           = 0644,
4710 			.proc_handler   = proc_dointvec
4711 		},
4712 		{
4713 			.procname       = "ndisc_notify",
4714 			.data           = &ipv6_devconf.ndisc_notify,
4715 			.maxlen         = sizeof(int),
4716 			.mode           = 0644,
4717 			.proc_handler   = proc_dointvec
4718 		},
4719 		{
4720 			/* sentinel */
4721 		}
4722 	},
4723 };
4724 
4725 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
4726 		struct inet6_dev *idev, struct ipv6_devconf *p)
4727 {
4728 	int i;
4729 	struct addrconf_sysctl_table *t;
4730 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
4731 
4732 	t = kmemdup(&addrconf_sysctl, sizeof(*t), GFP_KERNEL);
4733 	if (t == NULL)
4734 		goto out;
4735 
4736 	for (i = 0; t->addrconf_vars[i].data; i++) {
4737 		t->addrconf_vars[i].data += (char *)p - (char *)&ipv6_devconf;
4738 		t->addrconf_vars[i].extra1 = idev; /* embedded; no ref */
4739 		t->addrconf_vars[i].extra2 = net;
4740 	}
4741 
4742 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
4743 
4744 	t->sysctl_header = register_net_sysctl(net, path, t->addrconf_vars);
4745 	if (t->sysctl_header == NULL)
4746 		goto free;
4747 
4748 	p->sysctl = t;
4749 	return 0;
4750 
4751 free:
4752 	kfree(t);
4753 out:
4754 	return -ENOBUFS;
4755 }
4756 
4757 static void __addrconf_sysctl_unregister(struct ipv6_devconf *p)
4758 {
4759 	struct addrconf_sysctl_table *t;
4760 
4761 	if (p->sysctl == NULL)
4762 		return;
4763 
4764 	t = p->sysctl;
4765 	p->sysctl = NULL;
4766 	unregister_net_sysctl_table(t->sysctl_header);
4767 	kfree(t);
4768 }
4769 
4770 static void addrconf_sysctl_register(struct inet6_dev *idev)
4771 {
4772 	neigh_sysctl_register(idev->dev, idev->nd_parms, "ipv6",
4773 			      &ndisc_ifinfo_sysctl_change);
4774 	__addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
4775 					idev, &idev->cnf);
4776 }
4777 
4778 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
4779 {
4780 	__addrconf_sysctl_unregister(&idev->cnf);
4781 	neigh_sysctl_unregister(idev->nd_parms);
4782 }
4783 
4784 
4785 #endif
4786 
4787 static int __net_init addrconf_init_net(struct net *net)
4788 {
4789 	int err;
4790 	struct ipv6_devconf *all, *dflt;
4791 
4792 	err = -ENOMEM;
4793 	all = &ipv6_devconf;
4794 	dflt = &ipv6_devconf_dflt;
4795 
4796 	if (!net_eq(net, &init_net)) {
4797 		all = kmemdup(all, sizeof(ipv6_devconf), GFP_KERNEL);
4798 		if (all == NULL)
4799 			goto err_alloc_all;
4800 
4801 		dflt = kmemdup(dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
4802 		if (dflt == NULL)
4803 			goto err_alloc_dflt;
4804 	} else {
4805 		/* these will be inherited by all namespaces */
4806 		dflt->autoconf = ipv6_defaults.autoconf;
4807 		dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
4808 	}
4809 
4810 	net->ipv6.devconf_all = all;
4811 	net->ipv6.devconf_dflt = dflt;
4812 
4813 #ifdef CONFIG_SYSCTL
4814 	err = __addrconf_sysctl_register(net, "all", NULL, all);
4815 	if (err < 0)
4816 		goto err_reg_all;
4817 
4818 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
4819 	if (err < 0)
4820 		goto err_reg_dflt;
4821 #endif
4822 	return 0;
4823 
4824 #ifdef CONFIG_SYSCTL
4825 err_reg_dflt:
4826 	__addrconf_sysctl_unregister(all);
4827 err_reg_all:
4828 	kfree(dflt);
4829 #endif
4830 err_alloc_dflt:
4831 	kfree(all);
4832 err_alloc_all:
4833 	return err;
4834 }
4835 
4836 static void __net_exit addrconf_exit_net(struct net *net)
4837 {
4838 #ifdef CONFIG_SYSCTL
4839 	__addrconf_sysctl_unregister(net->ipv6.devconf_dflt);
4840 	__addrconf_sysctl_unregister(net->ipv6.devconf_all);
4841 #endif
4842 	if (!net_eq(net, &init_net)) {
4843 		kfree(net->ipv6.devconf_dflt);
4844 		kfree(net->ipv6.devconf_all);
4845 	}
4846 }
4847 
4848 static struct pernet_operations addrconf_ops = {
4849 	.init = addrconf_init_net,
4850 	.exit = addrconf_exit_net,
4851 };
4852 
4853 /*
4854  *      Device notifier
4855  */
4856 
4857 int register_inet6addr_notifier(struct notifier_block *nb)
4858 {
4859 	return atomic_notifier_chain_register(&inet6addr_chain, nb);
4860 }
4861 EXPORT_SYMBOL(register_inet6addr_notifier);
4862 
4863 int unregister_inet6addr_notifier(struct notifier_block *nb)
4864 {
4865 	return atomic_notifier_chain_unregister(&inet6addr_chain, nb);
4866 }
4867 EXPORT_SYMBOL(unregister_inet6addr_notifier);
4868 
4869 static struct rtnl_af_ops inet6_ops = {
4870 	.family		  = AF_INET6,
4871 	.fill_link_af	  = inet6_fill_link_af,
4872 	.get_link_af_size = inet6_get_link_af_size,
4873 };
4874 
4875 /*
4876  *	Init / cleanup code
4877  */
4878 
4879 int __init addrconf_init(void)
4880 {
4881 	int i, err;
4882 
4883 	err = ipv6_addr_label_init();
4884 	if (err < 0) {
4885 		pr_crit("%s: cannot initialize default policy table: %d\n",
4886 			__func__, err);
4887 		goto out;
4888 	}
4889 
4890 	err = register_pernet_subsys(&addrconf_ops);
4891 	if (err < 0)
4892 		goto out_addrlabel;
4893 
4894 	/* The addrconf netdev notifier requires that loopback_dev
4895 	 * has it's ipv6 private information allocated and setup
4896 	 * before it can bring up and give link-local addresses
4897 	 * to other devices which are up.
4898 	 *
4899 	 * Unfortunately, loopback_dev is not necessarily the first
4900 	 * entry in the global dev_base list of net devices.  In fact,
4901 	 * it is likely to be the very last entry on that list.
4902 	 * So this causes the notifier registry below to try and
4903 	 * give link-local addresses to all devices besides loopback_dev
4904 	 * first, then loopback_dev, which cases all the non-loopback_dev
4905 	 * devices to fail to get a link-local address.
4906 	 *
4907 	 * So, as a temporary fix, allocate the ipv6 structure for
4908 	 * loopback_dev first by hand.
4909 	 * Longer term, all of the dependencies ipv6 has upon the loopback
4910 	 * device and it being up should be removed.
4911 	 */
4912 	rtnl_lock();
4913 	if (!ipv6_add_dev(init_net.loopback_dev))
4914 		err = -ENOMEM;
4915 	rtnl_unlock();
4916 	if (err)
4917 		goto errlo;
4918 
4919 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
4920 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
4921 
4922 	register_netdevice_notifier(&ipv6_dev_notf);
4923 
4924 	addrconf_verify(0);
4925 
4926 	err = rtnl_af_register(&inet6_ops);
4927 	if (err < 0)
4928 		goto errout_af;
4929 
4930 	err = __rtnl_register(PF_INET6, RTM_GETLINK, NULL, inet6_dump_ifinfo,
4931 			      NULL);
4932 	if (err < 0)
4933 		goto errout;
4934 
4935 	/* Only the first call to __rtnl_register can fail */
4936 	__rtnl_register(PF_INET6, RTM_NEWADDR, inet6_rtm_newaddr, NULL, NULL);
4937 	__rtnl_register(PF_INET6, RTM_DELADDR, inet6_rtm_deladdr, NULL, NULL);
4938 	__rtnl_register(PF_INET6, RTM_GETADDR, inet6_rtm_getaddr,
4939 			inet6_dump_ifaddr, NULL);
4940 	__rtnl_register(PF_INET6, RTM_GETMULTICAST, NULL,
4941 			inet6_dump_ifmcaddr, NULL);
4942 	__rtnl_register(PF_INET6, RTM_GETANYCAST, NULL,
4943 			inet6_dump_ifacaddr, NULL);
4944 	__rtnl_register(PF_INET6, RTM_GETNETCONF, inet6_netconf_get_devconf,
4945 			NULL, NULL);
4946 
4947 	ipv6_addr_label_rtnl_register();
4948 
4949 	return 0;
4950 errout:
4951 	rtnl_af_unregister(&inet6_ops);
4952 errout_af:
4953 	unregister_netdevice_notifier(&ipv6_dev_notf);
4954 errlo:
4955 	unregister_pernet_subsys(&addrconf_ops);
4956 out_addrlabel:
4957 	ipv6_addr_label_cleanup();
4958 out:
4959 	return err;
4960 }
4961 
4962 void addrconf_cleanup(void)
4963 {
4964 	struct net_device *dev;
4965 	int i;
4966 
4967 	unregister_netdevice_notifier(&ipv6_dev_notf);
4968 	unregister_pernet_subsys(&addrconf_ops);
4969 	ipv6_addr_label_cleanup();
4970 
4971 	rtnl_lock();
4972 
4973 	__rtnl_af_unregister(&inet6_ops);
4974 
4975 	/* clean dev list */
4976 	for_each_netdev(&init_net, dev) {
4977 		if (__in6_dev_get(dev) == NULL)
4978 			continue;
4979 		addrconf_ifdown(dev, 1);
4980 	}
4981 	addrconf_ifdown(init_net.loopback_dev, 2);
4982 
4983 	/*
4984 	 *	Check hash table.
4985 	 */
4986 	spin_lock_bh(&addrconf_hash_lock);
4987 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
4988 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
4989 	spin_unlock_bh(&addrconf_hash_lock);
4990 
4991 	del_timer(&addr_chk_timer);
4992 	rtnl_unlock();
4993 }
4994