xref: /openbmc/linux/net/ipv6/addrconf.c (revision dd5b2498)
1 /*
2  *	IPv6 Address [auto]configuration
3  *	Linux INET6 implementation
4  *
5  *	Authors:
6  *	Pedro Roque		<roque@di.fc.ul.pt>
7  *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
8  *
9  *	This program is free software; you can redistribute it and/or
10  *      modify it under the terms of the GNU General Public License
11  *      as published by the Free Software Foundation; either version
12  *      2 of the License, or (at your option) any later version.
13  */
14 
15 /*
16  *	Changes:
17  *
18  *	Janos Farkas			:	delete timer on ifdown
19  *	<chexum@bankinf.banki.hu>
20  *	Andi Kleen			:	kill double kfree on module
21  *						unload.
22  *	Maciej W. Rozycki		:	FDDI support
23  *	sekiya@USAGI			:	Don't send too many RS
24  *						packets.
25  *	yoshfuji@USAGI			:       Fixed interval between DAD
26  *						packets.
27  *	YOSHIFUJI Hideaki @USAGI	:	improved accuracy of
28  *						address validation timer.
29  *	YOSHIFUJI Hideaki @USAGI	:	Privacy Extensions (RFC3041)
30  *						support.
31  *	Yuji SEKIYA @USAGI		:	Don't assign a same IPv6
32  *						address on a same interface.
33  *	YOSHIFUJI Hideaki @USAGI	:	ARCnet support
34  *	YOSHIFUJI Hideaki @USAGI	:	convert /proc/net/if_inet6 to
35  *						seq_file.
36  *	YOSHIFUJI Hideaki @USAGI	:	improved source address
37  *						selection; consider scope,
38  *						status etc.
39  */
40 
41 #define pr_fmt(fmt) "IPv6: " fmt
42 
43 #include <linux/errno.h>
44 #include <linux/types.h>
45 #include <linux/kernel.h>
46 #include <linux/sched/signal.h>
47 #include <linux/socket.h>
48 #include <linux/sockios.h>
49 #include <linux/net.h>
50 #include <linux/inet.h>
51 #include <linux/in6.h>
52 #include <linux/netdevice.h>
53 #include <linux/if_addr.h>
54 #include <linux/if_arp.h>
55 #include <linux/if_arcnet.h>
56 #include <linux/if_infiniband.h>
57 #include <linux/route.h>
58 #include <linux/inetdevice.h>
59 #include <linux/init.h>
60 #include <linux/slab.h>
61 #ifdef CONFIG_SYSCTL
62 #include <linux/sysctl.h>
63 #endif
64 #include <linux/capability.h>
65 #include <linux/delay.h>
66 #include <linux/notifier.h>
67 #include <linux/string.h>
68 #include <linux/hash.h>
69 
70 #include <net/net_namespace.h>
71 #include <net/sock.h>
72 #include <net/snmp.h>
73 
74 #include <net/6lowpan.h>
75 #include <net/firewire.h>
76 #include <net/ipv6.h>
77 #include <net/protocol.h>
78 #include <net/ndisc.h>
79 #include <net/ip6_route.h>
80 #include <net/addrconf.h>
81 #include <net/tcp.h>
82 #include <net/ip.h>
83 #include <net/netlink.h>
84 #include <net/pkt_sched.h>
85 #include <net/l3mdev.h>
86 #include <linux/if_tunnel.h>
87 #include <linux/rtnetlink.h>
88 #include <linux/netconf.h>
89 #include <linux/random.h>
90 #include <linux/uaccess.h>
91 #include <asm/unaligned.h>
92 
93 #include <linux/proc_fs.h>
94 #include <linux/seq_file.h>
95 #include <linux/export.h>
96 
97 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
98 
99 #define IPV6_MAX_STRLEN \
100 	sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")
101 
102 static inline u32 cstamp_delta(unsigned long cstamp)
103 {
104 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
105 }
106 
107 static inline s32 rfc3315_s14_backoff_init(s32 irt)
108 {
109 	/* multiply 'initial retransmission time' by 0.9 .. 1.1 */
110 	u64 tmp = (900000 + prandom_u32() % 200001) * (u64)irt;
111 	do_div(tmp, 1000000);
112 	return (s32)tmp;
113 }
114 
115 static inline s32 rfc3315_s14_backoff_update(s32 rt, s32 mrt)
116 {
117 	/* multiply 'retransmission timeout' by 1.9 .. 2.1 */
118 	u64 tmp = (1900000 + prandom_u32() % 200001) * (u64)rt;
119 	do_div(tmp, 1000000);
120 	if ((s32)tmp > mrt) {
121 		/* multiply 'maximum retransmission time' by 0.9 .. 1.1 */
122 		tmp = (900000 + prandom_u32() % 200001) * (u64)mrt;
123 		do_div(tmp, 1000000);
124 	}
125 	return (s32)tmp;
126 }
127 
128 #ifdef CONFIG_SYSCTL
129 static int addrconf_sysctl_register(struct inet6_dev *idev);
130 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
131 #else
132 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
133 {
134 	return 0;
135 }
136 
137 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
138 {
139 }
140 #endif
141 
142 static void ipv6_regen_rndid(struct inet6_dev *idev);
143 static void ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr);
144 
145 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
146 static int ipv6_count_addresses(const struct inet6_dev *idev);
147 static int ipv6_generate_stable_address(struct in6_addr *addr,
148 					u8 dad_count,
149 					const struct inet6_dev *idev);
150 
151 #define IN6_ADDR_HSIZE_SHIFT	8
152 #define IN6_ADDR_HSIZE		(1 << IN6_ADDR_HSIZE_SHIFT)
153 /*
154  *	Configured unicast address hash table
155  */
156 static struct hlist_head inet6_addr_lst[IN6_ADDR_HSIZE];
157 static DEFINE_SPINLOCK(addrconf_hash_lock);
158 
159 static void addrconf_verify(void);
160 static void addrconf_verify_rtnl(void);
161 static void addrconf_verify_work(struct work_struct *);
162 
163 static struct workqueue_struct *addrconf_wq;
164 static DECLARE_DELAYED_WORK(addr_chk_work, addrconf_verify_work);
165 
166 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
167 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
168 
169 static void addrconf_type_change(struct net_device *dev,
170 				 unsigned long event);
171 static int addrconf_ifdown(struct net_device *dev, int how);
172 
173 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
174 						  int plen,
175 						  const struct net_device *dev,
176 						  u32 flags, u32 noflags,
177 						  bool no_gw);
178 
179 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
180 static void addrconf_dad_work(struct work_struct *w);
181 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
182 				   bool send_na);
183 static void addrconf_dad_run(struct inet6_dev *idev, bool restart);
184 static void addrconf_rs_timer(struct timer_list *t);
185 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
186 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
187 
188 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
189 				struct prefix_info *pinfo);
190 
191 static struct ipv6_devconf ipv6_devconf __read_mostly = {
192 	.forwarding		= 0,
193 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
194 	.mtu6			= IPV6_MIN_MTU,
195 	.accept_ra		= 1,
196 	.accept_redirects	= 1,
197 	.autoconf		= 1,
198 	.force_mld_version	= 0,
199 	.mldv1_unsolicited_report_interval = 10 * HZ,
200 	.mldv2_unsolicited_report_interval = HZ,
201 	.dad_transmits		= 1,
202 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
203 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
204 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
205 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
206 	.use_tempaddr		= 0,
207 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
208 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
209 	.regen_max_retry	= REGEN_MAX_RETRY,
210 	.max_desync_factor	= MAX_DESYNC_FACTOR,
211 	.max_addresses		= IPV6_MAX_ADDRESSES,
212 	.accept_ra_defrtr	= 1,
213 	.accept_ra_from_local	= 0,
214 	.accept_ra_min_hop_limit= 1,
215 	.accept_ra_pinfo	= 1,
216 #ifdef CONFIG_IPV6_ROUTER_PREF
217 	.accept_ra_rtr_pref	= 1,
218 	.rtr_probe_interval	= 60 * HZ,
219 #ifdef CONFIG_IPV6_ROUTE_INFO
220 	.accept_ra_rt_info_min_plen = 0,
221 	.accept_ra_rt_info_max_plen = 0,
222 #endif
223 #endif
224 	.proxy_ndp		= 0,
225 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
226 	.disable_ipv6		= 0,
227 	.accept_dad		= 0,
228 	.suppress_frag_ndisc	= 1,
229 	.accept_ra_mtu		= 1,
230 	.stable_secret		= {
231 		.initialized = false,
232 	},
233 	.use_oif_addrs_only	= 0,
234 	.ignore_routes_with_linkdown = 0,
235 	.keep_addr_on_down	= 0,
236 	.seg6_enabled		= 0,
237 #ifdef CONFIG_IPV6_SEG6_HMAC
238 	.seg6_require_hmac	= 0,
239 #endif
240 	.enhanced_dad           = 1,
241 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
242 	.disable_policy		= 0,
243 };
244 
245 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
246 	.forwarding		= 0,
247 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
248 	.mtu6			= IPV6_MIN_MTU,
249 	.accept_ra		= 1,
250 	.accept_redirects	= 1,
251 	.autoconf		= 1,
252 	.force_mld_version	= 0,
253 	.mldv1_unsolicited_report_interval = 10 * HZ,
254 	.mldv2_unsolicited_report_interval = HZ,
255 	.dad_transmits		= 1,
256 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
257 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
258 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
259 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
260 	.use_tempaddr		= 0,
261 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
262 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
263 	.regen_max_retry	= REGEN_MAX_RETRY,
264 	.max_desync_factor	= MAX_DESYNC_FACTOR,
265 	.max_addresses		= IPV6_MAX_ADDRESSES,
266 	.accept_ra_defrtr	= 1,
267 	.accept_ra_from_local	= 0,
268 	.accept_ra_min_hop_limit= 1,
269 	.accept_ra_pinfo	= 1,
270 #ifdef CONFIG_IPV6_ROUTER_PREF
271 	.accept_ra_rtr_pref	= 1,
272 	.rtr_probe_interval	= 60 * HZ,
273 #ifdef CONFIG_IPV6_ROUTE_INFO
274 	.accept_ra_rt_info_min_plen = 0,
275 	.accept_ra_rt_info_max_plen = 0,
276 #endif
277 #endif
278 	.proxy_ndp		= 0,
279 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
280 	.disable_ipv6		= 0,
281 	.accept_dad		= 1,
282 	.suppress_frag_ndisc	= 1,
283 	.accept_ra_mtu		= 1,
284 	.stable_secret		= {
285 		.initialized = false,
286 	},
287 	.use_oif_addrs_only	= 0,
288 	.ignore_routes_with_linkdown = 0,
289 	.keep_addr_on_down	= 0,
290 	.seg6_enabled		= 0,
291 #ifdef CONFIG_IPV6_SEG6_HMAC
292 	.seg6_require_hmac	= 0,
293 #endif
294 	.enhanced_dad           = 1,
295 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
296 	.disable_policy		= 0,
297 };
298 
299 /* Check if link is ready: is it up and is a valid qdisc available */
300 static inline bool addrconf_link_ready(const struct net_device *dev)
301 {
302 	return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
303 }
304 
305 static void addrconf_del_rs_timer(struct inet6_dev *idev)
306 {
307 	if (del_timer(&idev->rs_timer))
308 		__in6_dev_put(idev);
309 }
310 
311 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
312 {
313 	if (cancel_delayed_work(&ifp->dad_work))
314 		__in6_ifa_put(ifp);
315 }
316 
317 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
318 				  unsigned long when)
319 {
320 	if (!timer_pending(&idev->rs_timer))
321 		in6_dev_hold(idev);
322 	mod_timer(&idev->rs_timer, jiffies + when);
323 }
324 
325 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
326 				   unsigned long delay)
327 {
328 	in6_ifa_hold(ifp);
329 	if (mod_delayed_work(addrconf_wq, &ifp->dad_work, delay))
330 		in6_ifa_put(ifp);
331 }
332 
333 static int snmp6_alloc_dev(struct inet6_dev *idev)
334 {
335 	int i;
336 
337 	idev->stats.ipv6 = alloc_percpu(struct ipstats_mib);
338 	if (!idev->stats.ipv6)
339 		goto err_ip;
340 
341 	for_each_possible_cpu(i) {
342 		struct ipstats_mib *addrconf_stats;
343 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
344 		u64_stats_init(&addrconf_stats->syncp);
345 	}
346 
347 
348 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
349 					GFP_KERNEL);
350 	if (!idev->stats.icmpv6dev)
351 		goto err_icmp;
352 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
353 					   GFP_KERNEL);
354 	if (!idev->stats.icmpv6msgdev)
355 		goto err_icmpmsg;
356 
357 	return 0;
358 
359 err_icmpmsg:
360 	kfree(idev->stats.icmpv6dev);
361 err_icmp:
362 	free_percpu(idev->stats.ipv6);
363 err_ip:
364 	return -ENOMEM;
365 }
366 
367 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
368 {
369 	struct inet6_dev *ndev;
370 	int err = -ENOMEM;
371 
372 	ASSERT_RTNL();
373 
374 	if (dev->mtu < IPV6_MIN_MTU)
375 		return ERR_PTR(-EINVAL);
376 
377 	ndev = kzalloc(sizeof(struct inet6_dev), GFP_KERNEL);
378 	if (!ndev)
379 		return ERR_PTR(err);
380 
381 	rwlock_init(&ndev->lock);
382 	ndev->dev = dev;
383 	INIT_LIST_HEAD(&ndev->addr_list);
384 	timer_setup(&ndev->rs_timer, addrconf_rs_timer, 0);
385 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
386 
387 	if (ndev->cnf.stable_secret.initialized)
388 		ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
389 
390 	ndev->cnf.mtu6 = dev->mtu;
391 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
392 	if (!ndev->nd_parms) {
393 		kfree(ndev);
394 		return ERR_PTR(err);
395 	}
396 	if (ndev->cnf.forwarding)
397 		dev_disable_lro(dev);
398 	/* We refer to the device */
399 	dev_hold(dev);
400 
401 	if (snmp6_alloc_dev(ndev) < 0) {
402 		netdev_dbg(dev, "%s: cannot allocate memory for statistics\n",
403 			   __func__);
404 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
405 		dev_put(dev);
406 		kfree(ndev);
407 		return ERR_PTR(err);
408 	}
409 
410 	if (snmp6_register_dev(ndev) < 0) {
411 		netdev_dbg(dev, "%s: cannot create /proc/net/dev_snmp6/%s\n",
412 			   __func__, dev->name);
413 		goto err_release;
414 	}
415 
416 	/* One reference from device. */
417 	refcount_set(&ndev->refcnt, 1);
418 
419 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
420 		ndev->cnf.accept_dad = -1;
421 
422 #if IS_ENABLED(CONFIG_IPV6_SIT)
423 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
424 		pr_info("%s: Disabled Multicast RS\n", dev->name);
425 		ndev->cnf.rtr_solicits = 0;
426 	}
427 #endif
428 
429 	INIT_LIST_HEAD(&ndev->tempaddr_list);
430 	ndev->desync_factor = U32_MAX;
431 	if ((dev->flags&IFF_LOOPBACK) ||
432 	    dev->type == ARPHRD_TUNNEL ||
433 	    dev->type == ARPHRD_TUNNEL6 ||
434 	    dev->type == ARPHRD_SIT ||
435 	    dev->type == ARPHRD_NONE) {
436 		ndev->cnf.use_tempaddr = -1;
437 	} else
438 		ipv6_regen_rndid(ndev);
439 
440 	ndev->token = in6addr_any;
441 
442 	if (netif_running(dev) && addrconf_link_ready(dev))
443 		ndev->if_flags |= IF_READY;
444 
445 	ipv6_mc_init_dev(ndev);
446 	ndev->tstamp = jiffies;
447 	err = addrconf_sysctl_register(ndev);
448 	if (err) {
449 		ipv6_mc_destroy_dev(ndev);
450 		snmp6_unregister_dev(ndev);
451 		goto err_release;
452 	}
453 	/* protected by rtnl_lock */
454 	rcu_assign_pointer(dev->ip6_ptr, ndev);
455 
456 	/* Join interface-local all-node multicast group */
457 	ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
458 
459 	/* Join all-node multicast group */
460 	ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
461 
462 	/* Join all-router multicast group if forwarding is set */
463 	if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
464 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
465 
466 	return ndev;
467 
468 err_release:
469 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
470 	ndev->dead = 1;
471 	in6_dev_finish_destroy(ndev);
472 	return ERR_PTR(err);
473 }
474 
475 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
476 {
477 	struct inet6_dev *idev;
478 
479 	ASSERT_RTNL();
480 
481 	idev = __in6_dev_get(dev);
482 	if (!idev) {
483 		idev = ipv6_add_dev(dev);
484 		if (IS_ERR(idev))
485 			return NULL;
486 	}
487 
488 	if (dev->flags&IFF_UP)
489 		ipv6_mc_up(idev);
490 	return idev;
491 }
492 
493 static int inet6_netconf_msgsize_devconf(int type)
494 {
495 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
496 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
497 	bool all = false;
498 
499 	if (type == NETCONFA_ALL)
500 		all = true;
501 
502 	if (all || type == NETCONFA_FORWARDING)
503 		size += nla_total_size(4);
504 #ifdef CONFIG_IPV6_MROUTE
505 	if (all || type == NETCONFA_MC_FORWARDING)
506 		size += nla_total_size(4);
507 #endif
508 	if (all || type == NETCONFA_PROXY_NEIGH)
509 		size += nla_total_size(4);
510 
511 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
512 		size += nla_total_size(4);
513 
514 	return size;
515 }
516 
517 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
518 				      struct ipv6_devconf *devconf, u32 portid,
519 				      u32 seq, int event, unsigned int flags,
520 				      int type)
521 {
522 	struct nlmsghdr  *nlh;
523 	struct netconfmsg *ncm;
524 	bool all = false;
525 
526 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
527 			flags);
528 	if (!nlh)
529 		return -EMSGSIZE;
530 
531 	if (type == NETCONFA_ALL)
532 		all = true;
533 
534 	ncm = nlmsg_data(nlh);
535 	ncm->ncm_family = AF_INET6;
536 
537 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
538 		goto nla_put_failure;
539 
540 	if (!devconf)
541 		goto out;
542 
543 	if ((all || type == NETCONFA_FORWARDING) &&
544 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
545 		goto nla_put_failure;
546 #ifdef CONFIG_IPV6_MROUTE
547 	if ((all || type == NETCONFA_MC_FORWARDING) &&
548 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
549 			devconf->mc_forwarding) < 0)
550 		goto nla_put_failure;
551 #endif
552 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
553 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
554 		goto nla_put_failure;
555 
556 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
557 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
558 			devconf->ignore_routes_with_linkdown) < 0)
559 		goto nla_put_failure;
560 
561 out:
562 	nlmsg_end(skb, nlh);
563 	return 0;
564 
565 nla_put_failure:
566 	nlmsg_cancel(skb, nlh);
567 	return -EMSGSIZE;
568 }
569 
570 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
571 				  int ifindex, struct ipv6_devconf *devconf)
572 {
573 	struct sk_buff *skb;
574 	int err = -ENOBUFS;
575 
576 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
577 	if (!skb)
578 		goto errout;
579 
580 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
581 					 event, 0, type);
582 	if (err < 0) {
583 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
584 		WARN_ON(err == -EMSGSIZE);
585 		kfree_skb(skb);
586 		goto errout;
587 	}
588 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
589 	return;
590 errout:
591 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
592 }
593 
594 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
595 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
596 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
597 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
598 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
599 };
600 
601 static int inet6_netconf_valid_get_req(struct sk_buff *skb,
602 				       const struct nlmsghdr *nlh,
603 				       struct nlattr **tb,
604 				       struct netlink_ext_ack *extack)
605 {
606 	int i, err;
607 
608 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(struct netconfmsg))) {
609 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf get request");
610 		return -EINVAL;
611 	}
612 
613 	if (!netlink_strict_get_check(skb))
614 		return nlmsg_parse(nlh, sizeof(struct netconfmsg), tb,
615 				   NETCONFA_MAX, devconf_ipv6_policy, extack);
616 
617 	err = nlmsg_parse_strict(nlh, sizeof(struct netconfmsg), tb,
618 				 NETCONFA_MAX, devconf_ipv6_policy, extack);
619 	if (err)
620 		return err;
621 
622 	for (i = 0; i <= NETCONFA_MAX; i++) {
623 		if (!tb[i])
624 			continue;
625 
626 		switch (i) {
627 		case NETCONFA_IFINDEX:
628 			break;
629 		default:
630 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in netconf get request");
631 			return -EINVAL;
632 		}
633 	}
634 
635 	return 0;
636 }
637 
638 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
639 				     struct nlmsghdr *nlh,
640 				     struct netlink_ext_ack *extack)
641 {
642 	struct net *net = sock_net(in_skb->sk);
643 	struct nlattr *tb[NETCONFA_MAX+1];
644 	struct inet6_dev *in6_dev = NULL;
645 	struct net_device *dev = NULL;
646 	struct sk_buff *skb;
647 	struct ipv6_devconf *devconf;
648 	int ifindex;
649 	int err;
650 
651 	err = inet6_netconf_valid_get_req(in_skb, nlh, tb, extack);
652 	if (err < 0)
653 		return err;
654 
655 	if (!tb[NETCONFA_IFINDEX])
656 		return -EINVAL;
657 
658 	err = -EINVAL;
659 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
660 	switch (ifindex) {
661 	case NETCONFA_IFINDEX_ALL:
662 		devconf = net->ipv6.devconf_all;
663 		break;
664 	case NETCONFA_IFINDEX_DEFAULT:
665 		devconf = net->ipv6.devconf_dflt;
666 		break;
667 	default:
668 		dev = dev_get_by_index(net, ifindex);
669 		if (!dev)
670 			return -EINVAL;
671 		in6_dev = in6_dev_get(dev);
672 		if (!in6_dev)
673 			goto errout;
674 		devconf = &in6_dev->cnf;
675 		break;
676 	}
677 
678 	err = -ENOBUFS;
679 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
680 	if (!skb)
681 		goto errout;
682 
683 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
684 					 NETLINK_CB(in_skb).portid,
685 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
686 					 NETCONFA_ALL);
687 	if (err < 0) {
688 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
689 		WARN_ON(err == -EMSGSIZE);
690 		kfree_skb(skb);
691 		goto errout;
692 	}
693 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
694 errout:
695 	if (in6_dev)
696 		in6_dev_put(in6_dev);
697 	if (dev)
698 		dev_put(dev);
699 	return err;
700 }
701 
702 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
703 				      struct netlink_callback *cb)
704 {
705 	const struct nlmsghdr *nlh = cb->nlh;
706 	struct net *net = sock_net(skb->sk);
707 	int h, s_h;
708 	int idx, s_idx;
709 	struct net_device *dev;
710 	struct inet6_dev *idev;
711 	struct hlist_head *head;
712 
713 	if (cb->strict_check) {
714 		struct netlink_ext_ack *extack = cb->extack;
715 		struct netconfmsg *ncm;
716 
717 		if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) {
718 			NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf dump request");
719 			return -EINVAL;
720 		}
721 
722 		if (nlmsg_attrlen(nlh, sizeof(*ncm))) {
723 			NL_SET_ERR_MSG_MOD(extack, "Invalid data after header in netconf dump request");
724 			return -EINVAL;
725 		}
726 	}
727 
728 	s_h = cb->args[0];
729 	s_idx = idx = cb->args[1];
730 
731 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
732 		idx = 0;
733 		head = &net->dev_index_head[h];
734 		rcu_read_lock();
735 		cb->seq = atomic_read(&net->ipv6.dev_addr_genid) ^
736 			  net->dev_base_seq;
737 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
738 			if (idx < s_idx)
739 				goto cont;
740 			idev = __in6_dev_get(dev);
741 			if (!idev)
742 				goto cont;
743 
744 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
745 						       &idev->cnf,
746 						       NETLINK_CB(cb->skb).portid,
747 						       nlh->nlmsg_seq,
748 						       RTM_NEWNETCONF,
749 						       NLM_F_MULTI,
750 						       NETCONFA_ALL) < 0) {
751 				rcu_read_unlock();
752 				goto done;
753 			}
754 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
755 cont:
756 			idx++;
757 		}
758 		rcu_read_unlock();
759 	}
760 	if (h == NETDEV_HASHENTRIES) {
761 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
762 					       net->ipv6.devconf_all,
763 					       NETLINK_CB(cb->skb).portid,
764 					       nlh->nlmsg_seq,
765 					       RTM_NEWNETCONF, NLM_F_MULTI,
766 					       NETCONFA_ALL) < 0)
767 			goto done;
768 		else
769 			h++;
770 	}
771 	if (h == NETDEV_HASHENTRIES + 1) {
772 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
773 					       net->ipv6.devconf_dflt,
774 					       NETLINK_CB(cb->skb).portid,
775 					       nlh->nlmsg_seq,
776 					       RTM_NEWNETCONF, NLM_F_MULTI,
777 					       NETCONFA_ALL) < 0)
778 			goto done;
779 		else
780 			h++;
781 	}
782 done:
783 	cb->args[0] = h;
784 	cb->args[1] = idx;
785 
786 	return skb->len;
787 }
788 
789 #ifdef CONFIG_SYSCTL
790 static void dev_forward_change(struct inet6_dev *idev)
791 {
792 	struct net_device *dev;
793 	struct inet6_ifaddr *ifa;
794 
795 	if (!idev)
796 		return;
797 	dev = idev->dev;
798 	if (idev->cnf.forwarding)
799 		dev_disable_lro(dev);
800 	if (dev->flags & IFF_MULTICAST) {
801 		if (idev->cnf.forwarding) {
802 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
803 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
804 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
805 		} else {
806 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
807 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
808 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
809 		}
810 	}
811 
812 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
813 		if (ifa->flags&IFA_F_TENTATIVE)
814 			continue;
815 		if (idev->cnf.forwarding)
816 			addrconf_join_anycast(ifa);
817 		else
818 			addrconf_leave_anycast(ifa);
819 	}
820 	inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
821 				     NETCONFA_FORWARDING,
822 				     dev->ifindex, &idev->cnf);
823 }
824 
825 
826 static void addrconf_forward_change(struct net *net, __s32 newf)
827 {
828 	struct net_device *dev;
829 	struct inet6_dev *idev;
830 
831 	for_each_netdev(net, dev) {
832 		idev = __in6_dev_get(dev);
833 		if (idev) {
834 			int changed = (!idev->cnf.forwarding) ^ (!newf);
835 			idev->cnf.forwarding = newf;
836 			if (changed)
837 				dev_forward_change(idev);
838 		}
839 	}
840 }
841 
842 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
843 {
844 	struct net *net;
845 	int old;
846 
847 	if (!rtnl_trylock())
848 		return restart_syscall();
849 
850 	net = (struct net *)table->extra2;
851 	old = *p;
852 	*p = newf;
853 
854 	if (p == &net->ipv6.devconf_dflt->forwarding) {
855 		if ((!newf) ^ (!old))
856 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
857 						     NETCONFA_FORWARDING,
858 						     NETCONFA_IFINDEX_DEFAULT,
859 						     net->ipv6.devconf_dflt);
860 		rtnl_unlock();
861 		return 0;
862 	}
863 
864 	if (p == &net->ipv6.devconf_all->forwarding) {
865 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
866 
867 		net->ipv6.devconf_dflt->forwarding = newf;
868 		if ((!newf) ^ (!old_dflt))
869 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
870 						     NETCONFA_FORWARDING,
871 						     NETCONFA_IFINDEX_DEFAULT,
872 						     net->ipv6.devconf_dflt);
873 
874 		addrconf_forward_change(net, newf);
875 		if ((!newf) ^ (!old))
876 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
877 						     NETCONFA_FORWARDING,
878 						     NETCONFA_IFINDEX_ALL,
879 						     net->ipv6.devconf_all);
880 	} else if ((!newf) ^ (!old))
881 		dev_forward_change((struct inet6_dev *)table->extra1);
882 	rtnl_unlock();
883 
884 	if (newf)
885 		rt6_purge_dflt_routers(net);
886 	return 1;
887 }
888 
889 static void addrconf_linkdown_change(struct net *net, __s32 newf)
890 {
891 	struct net_device *dev;
892 	struct inet6_dev *idev;
893 
894 	for_each_netdev(net, dev) {
895 		idev = __in6_dev_get(dev);
896 		if (idev) {
897 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
898 
899 			idev->cnf.ignore_routes_with_linkdown = newf;
900 			if (changed)
901 				inet6_netconf_notify_devconf(dev_net(dev),
902 							     RTM_NEWNETCONF,
903 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
904 							     dev->ifindex,
905 							     &idev->cnf);
906 		}
907 	}
908 }
909 
910 static int addrconf_fixup_linkdown(struct ctl_table *table, int *p, int newf)
911 {
912 	struct net *net;
913 	int old;
914 
915 	if (!rtnl_trylock())
916 		return restart_syscall();
917 
918 	net = (struct net *)table->extra2;
919 	old = *p;
920 	*p = newf;
921 
922 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
923 		if ((!newf) ^ (!old))
924 			inet6_netconf_notify_devconf(net,
925 						     RTM_NEWNETCONF,
926 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
927 						     NETCONFA_IFINDEX_DEFAULT,
928 						     net->ipv6.devconf_dflt);
929 		rtnl_unlock();
930 		return 0;
931 	}
932 
933 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
934 		net->ipv6.devconf_dflt->ignore_routes_with_linkdown = newf;
935 		addrconf_linkdown_change(net, newf);
936 		if ((!newf) ^ (!old))
937 			inet6_netconf_notify_devconf(net,
938 						     RTM_NEWNETCONF,
939 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
940 						     NETCONFA_IFINDEX_ALL,
941 						     net->ipv6.devconf_all);
942 	}
943 	rtnl_unlock();
944 
945 	return 1;
946 }
947 
948 #endif
949 
950 /* Nobody refers to this ifaddr, destroy it */
951 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
952 {
953 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
954 
955 #ifdef NET_REFCNT_DEBUG
956 	pr_debug("%s\n", __func__);
957 #endif
958 
959 	in6_dev_put(ifp->idev);
960 
961 	if (cancel_delayed_work(&ifp->dad_work))
962 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
963 			  ifp);
964 
965 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
966 		pr_warn("Freeing alive inet6 address %p\n", ifp);
967 		return;
968 	}
969 
970 	kfree_rcu(ifp, rcu);
971 }
972 
973 static void
974 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
975 {
976 	struct list_head *p;
977 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
978 
979 	/*
980 	 * Each device address list is sorted in order of scope -
981 	 * global before linklocal.
982 	 */
983 	list_for_each(p, &idev->addr_list) {
984 		struct inet6_ifaddr *ifa
985 			= list_entry(p, struct inet6_ifaddr, if_list);
986 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
987 			break;
988 	}
989 
990 	list_add_tail_rcu(&ifp->if_list, p);
991 }
992 
993 static u32 inet6_addr_hash(const struct net *net, const struct in6_addr *addr)
994 {
995 	u32 val = ipv6_addr_hash(addr) ^ net_hash_mix(net);
996 
997 	return hash_32(val, IN6_ADDR_HSIZE_SHIFT);
998 }
999 
1000 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1001 			       struct net_device *dev, unsigned int hash)
1002 {
1003 	struct inet6_ifaddr *ifp;
1004 
1005 	hlist_for_each_entry(ifp, &inet6_addr_lst[hash], addr_lst) {
1006 		if (!net_eq(dev_net(ifp->idev->dev), net))
1007 			continue;
1008 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1009 			if (!dev || ifp->idev->dev == dev)
1010 				return true;
1011 		}
1012 	}
1013 	return false;
1014 }
1015 
1016 static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
1017 {
1018 	unsigned int hash = inet6_addr_hash(dev_net(dev), &ifa->addr);
1019 	int err = 0;
1020 
1021 	spin_lock(&addrconf_hash_lock);
1022 
1023 	/* Ignore adding duplicate addresses on an interface */
1024 	if (ipv6_chk_same_addr(dev_net(dev), &ifa->addr, dev, hash)) {
1025 		netdev_dbg(dev, "ipv6_add_addr: already assigned\n");
1026 		err = -EEXIST;
1027 	} else {
1028 		hlist_add_head_rcu(&ifa->addr_lst, &inet6_addr_lst[hash]);
1029 	}
1030 
1031 	spin_unlock(&addrconf_hash_lock);
1032 
1033 	return err;
1034 }
1035 
1036 /* On success it returns ifp with increased reference count */
1037 
1038 static struct inet6_ifaddr *
1039 ipv6_add_addr(struct inet6_dev *idev, struct ifa6_config *cfg,
1040 	      bool can_block, struct netlink_ext_ack *extack)
1041 {
1042 	gfp_t gfp_flags = can_block ? GFP_KERNEL : GFP_ATOMIC;
1043 	int addr_type = ipv6_addr_type(cfg->pfx);
1044 	struct net *net = dev_net(idev->dev);
1045 	struct inet6_ifaddr *ifa = NULL;
1046 	struct fib6_info *f6i = NULL;
1047 	int err = 0;
1048 
1049 	if (addr_type == IPV6_ADDR_ANY ||
1050 	    addr_type & IPV6_ADDR_MULTICAST ||
1051 	    (!(idev->dev->flags & IFF_LOOPBACK) &&
1052 	     !netif_is_l3_master(idev->dev) &&
1053 	     addr_type & IPV6_ADDR_LOOPBACK))
1054 		return ERR_PTR(-EADDRNOTAVAIL);
1055 
1056 	if (idev->dead) {
1057 		err = -ENODEV;			/*XXX*/
1058 		goto out;
1059 	}
1060 
1061 	if (idev->cnf.disable_ipv6) {
1062 		err = -EACCES;
1063 		goto out;
1064 	}
1065 
1066 	/* validator notifier needs to be blocking;
1067 	 * do not call in atomic context
1068 	 */
1069 	if (can_block) {
1070 		struct in6_validator_info i6vi = {
1071 			.i6vi_addr = *cfg->pfx,
1072 			.i6vi_dev = idev,
1073 			.extack = extack,
1074 		};
1075 
1076 		err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
1077 		err = notifier_to_errno(err);
1078 		if (err < 0)
1079 			goto out;
1080 	}
1081 
1082 	ifa = kzalloc(sizeof(*ifa), gfp_flags);
1083 	if (!ifa) {
1084 		err = -ENOBUFS;
1085 		goto out;
1086 	}
1087 
1088 	f6i = addrconf_f6i_alloc(net, idev, cfg->pfx, false, gfp_flags);
1089 	if (IS_ERR(f6i)) {
1090 		err = PTR_ERR(f6i);
1091 		f6i = NULL;
1092 		goto out;
1093 	}
1094 
1095 	if (net->ipv6.devconf_all->disable_policy ||
1096 	    idev->cnf.disable_policy)
1097 		f6i->dst_nopolicy = true;
1098 
1099 	neigh_parms_data_state_setall(idev->nd_parms);
1100 
1101 	ifa->addr = *cfg->pfx;
1102 	if (cfg->peer_pfx)
1103 		ifa->peer_addr = *cfg->peer_pfx;
1104 
1105 	spin_lock_init(&ifa->lock);
1106 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1107 	INIT_HLIST_NODE(&ifa->addr_lst);
1108 	ifa->scope = cfg->scope;
1109 	ifa->prefix_len = cfg->plen;
1110 	ifa->rt_priority = cfg->rt_priority;
1111 	ifa->flags = cfg->ifa_flags;
1112 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1113 	if (!(cfg->ifa_flags & IFA_F_NODAD))
1114 		ifa->flags |= IFA_F_TENTATIVE;
1115 	ifa->valid_lft = cfg->valid_lft;
1116 	ifa->prefered_lft = cfg->preferred_lft;
1117 	ifa->cstamp = ifa->tstamp = jiffies;
1118 	ifa->tokenized = false;
1119 
1120 	ifa->rt = f6i;
1121 
1122 	ifa->idev = idev;
1123 	in6_dev_hold(idev);
1124 
1125 	/* For caller */
1126 	refcount_set(&ifa->refcnt, 1);
1127 
1128 	rcu_read_lock_bh();
1129 
1130 	err = ipv6_add_addr_hash(idev->dev, ifa);
1131 	if (err < 0) {
1132 		rcu_read_unlock_bh();
1133 		goto out;
1134 	}
1135 
1136 	write_lock(&idev->lock);
1137 
1138 	/* Add to inet6_dev unicast addr list. */
1139 	ipv6_link_dev_addr(idev, ifa);
1140 
1141 	if (ifa->flags&IFA_F_TEMPORARY) {
1142 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1143 		in6_ifa_hold(ifa);
1144 	}
1145 
1146 	in6_ifa_hold(ifa);
1147 	write_unlock(&idev->lock);
1148 
1149 	rcu_read_unlock_bh();
1150 
1151 	inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1152 out:
1153 	if (unlikely(err < 0)) {
1154 		fib6_info_release(f6i);
1155 
1156 		if (ifa) {
1157 			if (ifa->idev)
1158 				in6_dev_put(ifa->idev);
1159 			kfree(ifa);
1160 		}
1161 		ifa = ERR_PTR(err);
1162 	}
1163 
1164 	return ifa;
1165 }
1166 
1167 enum cleanup_prefix_rt_t {
1168 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1169 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1170 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1171 };
1172 
1173 /*
1174  * Check, whether the prefix for ifp would still need a prefix route
1175  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1176  * constants.
1177  *
1178  * 1) we don't purge prefix if address was not permanent.
1179  *    prefix is managed by its own lifetime.
1180  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1181  * 3) if there are no addresses, delete prefix.
1182  * 4) if there are still other permanent address(es),
1183  *    corresponding prefix is still permanent.
1184  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1185  *    don't purge the prefix, assume user space is managing it.
1186  * 6) otherwise, update prefix lifetime to the
1187  *    longest valid lifetime among the corresponding
1188  *    addresses on the device.
1189  *    Note: subsequent RA will update lifetime.
1190  **/
1191 static enum cleanup_prefix_rt_t
1192 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1193 {
1194 	struct inet6_ifaddr *ifa;
1195 	struct inet6_dev *idev = ifp->idev;
1196 	unsigned long lifetime;
1197 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1198 
1199 	*expires = jiffies;
1200 
1201 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1202 		if (ifa == ifp)
1203 			continue;
1204 		if (ifa->prefix_len != ifp->prefix_len ||
1205 		    !ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1206 				       ifp->prefix_len))
1207 			continue;
1208 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1209 			return CLEANUP_PREFIX_RT_NOP;
1210 
1211 		action = CLEANUP_PREFIX_RT_EXPIRE;
1212 
1213 		spin_lock(&ifa->lock);
1214 
1215 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1216 		/*
1217 		 * Note: Because this address is
1218 		 * not permanent, lifetime <
1219 		 * LONG_MAX / HZ here.
1220 		 */
1221 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1222 			*expires = ifa->tstamp + lifetime * HZ;
1223 		spin_unlock(&ifa->lock);
1224 	}
1225 
1226 	return action;
1227 }
1228 
1229 static void
1230 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires, bool del_rt)
1231 {
1232 	struct fib6_info *f6i;
1233 
1234 	f6i = addrconf_get_prefix_route(&ifp->addr, ifp->prefix_len,
1235 					ifp->idev->dev, 0, RTF_DEFAULT, true);
1236 	if (f6i) {
1237 		if (del_rt)
1238 			ip6_del_rt(dev_net(ifp->idev->dev), f6i);
1239 		else {
1240 			if (!(f6i->fib6_flags & RTF_EXPIRES))
1241 				fib6_set_expires(f6i, expires);
1242 			fib6_info_release(f6i);
1243 		}
1244 	}
1245 }
1246 
1247 
1248 /* This function wants to get referenced ifp and releases it before return */
1249 
1250 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1251 {
1252 	int state;
1253 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1254 	unsigned long expires;
1255 
1256 	ASSERT_RTNL();
1257 
1258 	spin_lock_bh(&ifp->lock);
1259 	state = ifp->state;
1260 	ifp->state = INET6_IFADDR_STATE_DEAD;
1261 	spin_unlock_bh(&ifp->lock);
1262 
1263 	if (state == INET6_IFADDR_STATE_DEAD)
1264 		goto out;
1265 
1266 	spin_lock_bh(&addrconf_hash_lock);
1267 	hlist_del_init_rcu(&ifp->addr_lst);
1268 	spin_unlock_bh(&addrconf_hash_lock);
1269 
1270 	write_lock_bh(&ifp->idev->lock);
1271 
1272 	if (ifp->flags&IFA_F_TEMPORARY) {
1273 		list_del(&ifp->tmp_list);
1274 		if (ifp->ifpub) {
1275 			in6_ifa_put(ifp->ifpub);
1276 			ifp->ifpub = NULL;
1277 		}
1278 		__in6_ifa_put(ifp);
1279 	}
1280 
1281 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1282 		action = check_cleanup_prefix_route(ifp, &expires);
1283 
1284 	list_del_rcu(&ifp->if_list);
1285 	__in6_ifa_put(ifp);
1286 
1287 	write_unlock_bh(&ifp->idev->lock);
1288 
1289 	addrconf_del_dad_work(ifp);
1290 
1291 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1292 
1293 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1294 
1295 	if (action != CLEANUP_PREFIX_RT_NOP) {
1296 		cleanup_prefix_route(ifp, expires,
1297 			action == CLEANUP_PREFIX_RT_DEL);
1298 	}
1299 
1300 	/* clean up prefsrc entries */
1301 	rt6_remove_prefsrc(ifp);
1302 out:
1303 	in6_ifa_put(ifp);
1304 }
1305 
1306 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp,
1307 				struct inet6_ifaddr *ift,
1308 				bool block)
1309 {
1310 	struct inet6_dev *idev = ifp->idev;
1311 	struct in6_addr addr, *tmpaddr;
1312 	unsigned long tmp_tstamp, age;
1313 	unsigned long regen_advance;
1314 	struct ifa6_config cfg;
1315 	int ret = 0;
1316 	unsigned long now = jiffies;
1317 	long max_desync_factor;
1318 	s32 cnf_temp_preferred_lft;
1319 
1320 	write_lock_bh(&idev->lock);
1321 	if (ift) {
1322 		spin_lock_bh(&ift->lock);
1323 		memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
1324 		spin_unlock_bh(&ift->lock);
1325 		tmpaddr = &addr;
1326 	} else {
1327 		tmpaddr = NULL;
1328 	}
1329 retry:
1330 	in6_dev_hold(idev);
1331 	if (idev->cnf.use_tempaddr <= 0) {
1332 		write_unlock_bh(&idev->lock);
1333 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1334 		in6_dev_put(idev);
1335 		ret = -1;
1336 		goto out;
1337 	}
1338 	spin_lock_bh(&ifp->lock);
1339 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1340 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1341 		spin_unlock_bh(&ifp->lock);
1342 		write_unlock_bh(&idev->lock);
1343 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1344 			__func__);
1345 		in6_dev_put(idev);
1346 		ret = -1;
1347 		goto out;
1348 	}
1349 	in6_ifa_hold(ifp);
1350 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1351 	ipv6_try_regen_rndid(idev, tmpaddr);
1352 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
1353 	age = (now - ifp->tstamp) / HZ;
1354 
1355 	regen_advance = idev->cnf.regen_max_retry *
1356 			idev->cnf.dad_transmits *
1357 			NEIGH_VAR(idev->nd_parms, RETRANS_TIME) / HZ;
1358 
1359 	/* recalculate max_desync_factor each time and update
1360 	 * idev->desync_factor if it's larger
1361 	 */
1362 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1363 	max_desync_factor = min_t(__u32,
1364 				  idev->cnf.max_desync_factor,
1365 				  cnf_temp_preferred_lft - regen_advance);
1366 
1367 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1368 		if (max_desync_factor > 0) {
1369 			get_random_bytes(&idev->desync_factor,
1370 					 sizeof(idev->desync_factor));
1371 			idev->desync_factor %= max_desync_factor;
1372 		} else {
1373 			idev->desync_factor = 0;
1374 		}
1375 	}
1376 
1377 	memset(&cfg, 0, sizeof(cfg));
1378 	cfg.valid_lft = min_t(__u32, ifp->valid_lft,
1379 			      idev->cnf.temp_valid_lft + age);
1380 	cfg.preferred_lft = cnf_temp_preferred_lft + age - idev->desync_factor;
1381 	cfg.preferred_lft = min_t(__u32, ifp->prefered_lft, cfg.preferred_lft);
1382 
1383 	cfg.plen = ifp->prefix_len;
1384 	tmp_tstamp = ifp->tstamp;
1385 	spin_unlock_bh(&ifp->lock);
1386 
1387 	write_unlock_bh(&idev->lock);
1388 
1389 	/* A temporary address is created only if this calculated Preferred
1390 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1391 	 * an implementation must not create a temporary address with a zero
1392 	 * Preferred Lifetime.
1393 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1394 	 * temporary addresses being generated.
1395 	 */
1396 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1397 	if (cfg.preferred_lft <= regen_advance + age) {
1398 		in6_ifa_put(ifp);
1399 		in6_dev_put(idev);
1400 		ret = -1;
1401 		goto out;
1402 	}
1403 
1404 	cfg.ifa_flags = IFA_F_TEMPORARY;
1405 	/* set in addrconf_prefix_rcv() */
1406 	if (ifp->flags & IFA_F_OPTIMISTIC)
1407 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
1408 
1409 	cfg.pfx = &addr;
1410 	cfg.scope = ipv6_addr_scope(cfg.pfx);
1411 
1412 	ift = ipv6_add_addr(idev, &cfg, block, NULL);
1413 	if (IS_ERR(ift)) {
1414 		in6_ifa_put(ifp);
1415 		in6_dev_put(idev);
1416 		pr_info("%s: retry temporary address regeneration\n", __func__);
1417 		tmpaddr = &addr;
1418 		write_lock_bh(&idev->lock);
1419 		goto retry;
1420 	}
1421 
1422 	spin_lock_bh(&ift->lock);
1423 	ift->ifpub = ifp;
1424 	ift->cstamp = now;
1425 	ift->tstamp = tmp_tstamp;
1426 	spin_unlock_bh(&ift->lock);
1427 
1428 	addrconf_dad_start(ift);
1429 	in6_ifa_put(ift);
1430 	in6_dev_put(idev);
1431 out:
1432 	return ret;
1433 }
1434 
1435 /*
1436  *	Choose an appropriate source address (RFC3484)
1437  */
1438 enum {
1439 	IPV6_SADDR_RULE_INIT = 0,
1440 	IPV6_SADDR_RULE_LOCAL,
1441 	IPV6_SADDR_RULE_SCOPE,
1442 	IPV6_SADDR_RULE_PREFERRED,
1443 #ifdef CONFIG_IPV6_MIP6
1444 	IPV6_SADDR_RULE_HOA,
1445 #endif
1446 	IPV6_SADDR_RULE_OIF,
1447 	IPV6_SADDR_RULE_LABEL,
1448 	IPV6_SADDR_RULE_PRIVACY,
1449 	IPV6_SADDR_RULE_ORCHID,
1450 	IPV6_SADDR_RULE_PREFIX,
1451 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1452 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1453 #endif
1454 	IPV6_SADDR_RULE_MAX
1455 };
1456 
1457 struct ipv6_saddr_score {
1458 	int			rule;
1459 	int			addr_type;
1460 	struct inet6_ifaddr	*ifa;
1461 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1462 	int			scopedist;
1463 	int			matchlen;
1464 };
1465 
1466 struct ipv6_saddr_dst {
1467 	const struct in6_addr *addr;
1468 	int ifindex;
1469 	int scope;
1470 	int label;
1471 	unsigned int prefs;
1472 };
1473 
1474 static inline int ipv6_saddr_preferred(int type)
1475 {
1476 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1477 		return 1;
1478 	return 0;
1479 }
1480 
1481 static bool ipv6_use_optimistic_addr(struct net *net,
1482 				     struct inet6_dev *idev)
1483 {
1484 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1485 	if (!idev)
1486 		return false;
1487 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1488 		return false;
1489 	if (!net->ipv6.devconf_all->use_optimistic && !idev->cnf.use_optimistic)
1490 		return false;
1491 
1492 	return true;
1493 #else
1494 	return false;
1495 #endif
1496 }
1497 
1498 static bool ipv6_allow_optimistic_dad(struct net *net,
1499 				      struct inet6_dev *idev)
1500 {
1501 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1502 	if (!idev)
1503 		return false;
1504 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1505 		return false;
1506 
1507 	return true;
1508 #else
1509 	return false;
1510 #endif
1511 }
1512 
1513 static int ipv6_get_saddr_eval(struct net *net,
1514 			       struct ipv6_saddr_score *score,
1515 			       struct ipv6_saddr_dst *dst,
1516 			       int i)
1517 {
1518 	int ret;
1519 
1520 	if (i <= score->rule) {
1521 		switch (i) {
1522 		case IPV6_SADDR_RULE_SCOPE:
1523 			ret = score->scopedist;
1524 			break;
1525 		case IPV6_SADDR_RULE_PREFIX:
1526 			ret = score->matchlen;
1527 			break;
1528 		default:
1529 			ret = !!test_bit(i, score->scorebits);
1530 		}
1531 		goto out;
1532 	}
1533 
1534 	switch (i) {
1535 	case IPV6_SADDR_RULE_INIT:
1536 		/* Rule 0: remember if hiscore is not ready yet */
1537 		ret = !!score->ifa;
1538 		break;
1539 	case IPV6_SADDR_RULE_LOCAL:
1540 		/* Rule 1: Prefer same address */
1541 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1542 		break;
1543 	case IPV6_SADDR_RULE_SCOPE:
1544 		/* Rule 2: Prefer appropriate scope
1545 		 *
1546 		 *      ret
1547 		 *       ^
1548 		 *    -1 |  d 15
1549 		 *    ---+--+-+---> scope
1550 		 *       |
1551 		 *       |             d is scope of the destination.
1552 		 *  B-d  |  \
1553 		 *       |   \      <- smaller scope is better if
1554 		 *  B-15 |    \        if scope is enough for destination.
1555 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1556 		 * d-C-1 | /
1557 		 *       |/         <- greater is better
1558 		 *   -C  /             if scope is not enough for destination.
1559 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1560 		 *
1561 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1562 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1563 		 * Assume B = 0 and we get C > 29.
1564 		 */
1565 		ret = __ipv6_addr_src_scope(score->addr_type);
1566 		if (ret >= dst->scope)
1567 			ret = -ret;
1568 		else
1569 			ret -= 128;	/* 30 is enough */
1570 		score->scopedist = ret;
1571 		break;
1572 	case IPV6_SADDR_RULE_PREFERRED:
1573 	    {
1574 		/* Rule 3: Avoid deprecated and optimistic addresses */
1575 		u8 avoid = IFA_F_DEPRECATED;
1576 
1577 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1578 			avoid |= IFA_F_OPTIMISTIC;
1579 		ret = ipv6_saddr_preferred(score->addr_type) ||
1580 		      !(score->ifa->flags & avoid);
1581 		break;
1582 	    }
1583 #ifdef CONFIG_IPV6_MIP6
1584 	case IPV6_SADDR_RULE_HOA:
1585 	    {
1586 		/* Rule 4: Prefer home address */
1587 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1588 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1589 		break;
1590 	    }
1591 #endif
1592 	case IPV6_SADDR_RULE_OIF:
1593 		/* Rule 5: Prefer outgoing interface */
1594 		ret = (!dst->ifindex ||
1595 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1596 		break;
1597 	case IPV6_SADDR_RULE_LABEL:
1598 		/* Rule 6: Prefer matching label */
1599 		ret = ipv6_addr_label(net,
1600 				      &score->ifa->addr, score->addr_type,
1601 				      score->ifa->idev->dev->ifindex) == dst->label;
1602 		break;
1603 	case IPV6_SADDR_RULE_PRIVACY:
1604 	    {
1605 		/* Rule 7: Prefer public address
1606 		 * Note: prefer temporary address if use_tempaddr >= 2
1607 		 */
1608 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1609 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1610 				score->ifa->idev->cnf.use_tempaddr >= 2;
1611 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1612 		break;
1613 	    }
1614 	case IPV6_SADDR_RULE_ORCHID:
1615 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1616 		 *	    non-ORCHID vs non-ORCHID
1617 		 */
1618 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1619 			ipv6_addr_orchid(dst->addr));
1620 		break;
1621 	case IPV6_SADDR_RULE_PREFIX:
1622 		/* Rule 8: Use longest matching prefix */
1623 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1624 		if (ret > score->ifa->prefix_len)
1625 			ret = score->ifa->prefix_len;
1626 		score->matchlen = ret;
1627 		break;
1628 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1629 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1630 		/* Optimistic addresses still have lower precedence than other
1631 		 * preferred addresses.
1632 		 */
1633 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1634 		break;
1635 #endif
1636 	default:
1637 		ret = 0;
1638 	}
1639 
1640 	if (ret)
1641 		__set_bit(i, score->scorebits);
1642 	score->rule = i;
1643 out:
1644 	return ret;
1645 }
1646 
1647 static int __ipv6_dev_get_saddr(struct net *net,
1648 				struct ipv6_saddr_dst *dst,
1649 				struct inet6_dev *idev,
1650 				struct ipv6_saddr_score *scores,
1651 				int hiscore_idx)
1652 {
1653 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1654 
1655 	list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1656 		int i;
1657 
1658 		/*
1659 		 * - Tentative Address (RFC2462 section 5.4)
1660 		 *  - A tentative address is not considered
1661 		 *    "assigned to an interface" in the traditional
1662 		 *    sense, unless it is also flagged as optimistic.
1663 		 * - Candidate Source Address (section 4)
1664 		 *  - In any case, anycast addresses, multicast
1665 		 *    addresses, and the unspecified address MUST
1666 		 *    NOT be included in a candidate set.
1667 		 */
1668 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1669 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1670 			continue;
1671 
1672 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1673 
1674 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1675 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1676 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1677 					    idev->dev->name);
1678 			continue;
1679 		}
1680 
1681 		score->rule = -1;
1682 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1683 
1684 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1685 			int minihiscore, miniscore;
1686 
1687 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1688 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1689 
1690 			if (minihiscore > miniscore) {
1691 				if (i == IPV6_SADDR_RULE_SCOPE &&
1692 				    score->scopedist > 0) {
1693 					/*
1694 					 * special case:
1695 					 * each remaining entry
1696 					 * has too small (not enough)
1697 					 * scope, because ifa entries
1698 					 * are sorted by their scope
1699 					 * values.
1700 					 */
1701 					goto out;
1702 				}
1703 				break;
1704 			} else if (minihiscore < miniscore) {
1705 				swap(hiscore, score);
1706 				hiscore_idx = 1 - hiscore_idx;
1707 
1708 				/* restore our iterator */
1709 				score->ifa = hiscore->ifa;
1710 
1711 				break;
1712 			}
1713 		}
1714 	}
1715 out:
1716 	return hiscore_idx;
1717 }
1718 
1719 static int ipv6_get_saddr_master(struct net *net,
1720 				 const struct net_device *dst_dev,
1721 				 const struct net_device *master,
1722 				 struct ipv6_saddr_dst *dst,
1723 				 struct ipv6_saddr_score *scores,
1724 				 int hiscore_idx)
1725 {
1726 	struct inet6_dev *idev;
1727 
1728 	idev = __in6_dev_get(dst_dev);
1729 	if (idev)
1730 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1731 						   scores, hiscore_idx);
1732 
1733 	idev = __in6_dev_get(master);
1734 	if (idev)
1735 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1736 						   scores, hiscore_idx);
1737 
1738 	return hiscore_idx;
1739 }
1740 
1741 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1742 		       const struct in6_addr *daddr, unsigned int prefs,
1743 		       struct in6_addr *saddr)
1744 {
1745 	struct ipv6_saddr_score scores[2], *hiscore;
1746 	struct ipv6_saddr_dst dst;
1747 	struct inet6_dev *idev;
1748 	struct net_device *dev;
1749 	int dst_type;
1750 	bool use_oif_addr = false;
1751 	int hiscore_idx = 0;
1752 	int ret = 0;
1753 
1754 	dst_type = __ipv6_addr_type(daddr);
1755 	dst.addr = daddr;
1756 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1757 	dst.scope = __ipv6_addr_src_scope(dst_type);
1758 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1759 	dst.prefs = prefs;
1760 
1761 	scores[hiscore_idx].rule = -1;
1762 	scores[hiscore_idx].ifa = NULL;
1763 
1764 	rcu_read_lock();
1765 
1766 	/* Candidate Source Address (section 4)
1767 	 *  - multicast and link-local destination address,
1768 	 *    the set of candidate source address MUST only
1769 	 *    include addresses assigned to interfaces
1770 	 *    belonging to the same link as the outgoing
1771 	 *    interface.
1772 	 * (- For site-local destination addresses, the
1773 	 *    set of candidate source addresses MUST only
1774 	 *    include addresses assigned to interfaces
1775 	 *    belonging to the same site as the outgoing
1776 	 *    interface.)
1777 	 *  - "It is RECOMMENDED that the candidate source addresses
1778 	 *    be the set of unicast addresses assigned to the
1779 	 *    interface that will be used to send to the destination
1780 	 *    (the 'outgoing' interface)." (RFC 6724)
1781 	 */
1782 	if (dst_dev) {
1783 		idev = __in6_dev_get(dst_dev);
1784 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1785 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1786 		    (idev && idev->cnf.use_oif_addrs_only)) {
1787 			use_oif_addr = true;
1788 		}
1789 	}
1790 
1791 	if (use_oif_addr) {
1792 		if (idev)
1793 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1794 	} else {
1795 		const struct net_device *master;
1796 		int master_idx = 0;
1797 
1798 		/* if dst_dev exists and is enslaved to an L3 device, then
1799 		 * prefer addresses from dst_dev and then the master over
1800 		 * any other enslaved devices in the L3 domain.
1801 		 */
1802 		master = l3mdev_master_dev_rcu(dst_dev);
1803 		if (master) {
1804 			master_idx = master->ifindex;
1805 
1806 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1807 							    master, &dst,
1808 							    scores, hiscore_idx);
1809 
1810 			if (scores[hiscore_idx].ifa)
1811 				goto out;
1812 		}
1813 
1814 		for_each_netdev_rcu(net, dev) {
1815 			/* only consider addresses on devices in the
1816 			 * same L3 domain
1817 			 */
1818 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1819 				continue;
1820 			idev = __in6_dev_get(dev);
1821 			if (!idev)
1822 				continue;
1823 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1824 		}
1825 	}
1826 
1827 out:
1828 	hiscore = &scores[hiscore_idx];
1829 	if (!hiscore->ifa)
1830 		ret = -EADDRNOTAVAIL;
1831 	else
1832 		*saddr = hiscore->ifa->addr;
1833 
1834 	rcu_read_unlock();
1835 	return ret;
1836 }
1837 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1838 
1839 int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1840 		      u32 banned_flags)
1841 {
1842 	struct inet6_ifaddr *ifp;
1843 	int err = -EADDRNOTAVAIL;
1844 
1845 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1846 		if (ifp->scope > IFA_LINK)
1847 			break;
1848 		if (ifp->scope == IFA_LINK &&
1849 		    !(ifp->flags & banned_flags)) {
1850 			*addr = ifp->addr;
1851 			err = 0;
1852 			break;
1853 		}
1854 	}
1855 	return err;
1856 }
1857 
1858 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1859 		    u32 banned_flags)
1860 {
1861 	struct inet6_dev *idev;
1862 	int err = -EADDRNOTAVAIL;
1863 
1864 	rcu_read_lock();
1865 	idev = __in6_dev_get(dev);
1866 	if (idev) {
1867 		read_lock_bh(&idev->lock);
1868 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1869 		read_unlock_bh(&idev->lock);
1870 	}
1871 	rcu_read_unlock();
1872 	return err;
1873 }
1874 
1875 static int ipv6_count_addresses(const struct inet6_dev *idev)
1876 {
1877 	const struct inet6_ifaddr *ifp;
1878 	int cnt = 0;
1879 
1880 	rcu_read_lock();
1881 	list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1882 		cnt++;
1883 	rcu_read_unlock();
1884 	return cnt;
1885 }
1886 
1887 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1888 		  const struct net_device *dev, int strict)
1889 {
1890 	return ipv6_chk_addr_and_flags(net, addr, dev, !dev,
1891 				       strict, IFA_F_TENTATIVE);
1892 }
1893 EXPORT_SYMBOL(ipv6_chk_addr);
1894 
1895 /* device argument is used to find the L3 domain of interest. If
1896  * skip_dev_check is set, then the ifp device is not checked against
1897  * the passed in dev argument. So the 2 cases for addresses checks are:
1898  *   1. does the address exist in the L3 domain that dev is part of
1899  *      (skip_dev_check = true), or
1900  *
1901  *   2. does the address exist on the specific device
1902  *      (skip_dev_check = false)
1903  */
1904 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1905 			    const struct net_device *dev, bool skip_dev_check,
1906 			    int strict, u32 banned_flags)
1907 {
1908 	unsigned int hash = inet6_addr_hash(net, addr);
1909 	const struct net_device *l3mdev;
1910 	struct inet6_ifaddr *ifp;
1911 	u32 ifp_flags;
1912 
1913 	rcu_read_lock();
1914 
1915 	l3mdev = l3mdev_master_dev_rcu(dev);
1916 	if (skip_dev_check)
1917 		dev = NULL;
1918 
1919 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
1920 		if (!net_eq(dev_net(ifp->idev->dev), net))
1921 			continue;
1922 
1923 		if (l3mdev_master_dev_rcu(ifp->idev->dev) != l3mdev)
1924 			continue;
1925 
1926 		/* Decouple optimistic from tentative for evaluation here.
1927 		 * Ban optimistic addresses explicitly, when required.
1928 		 */
1929 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1930 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1931 			    : ifp->flags;
1932 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1933 		    !(ifp_flags&banned_flags) &&
1934 		    (!dev || ifp->idev->dev == dev ||
1935 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1936 			rcu_read_unlock();
1937 			return 1;
1938 		}
1939 	}
1940 
1941 	rcu_read_unlock();
1942 	return 0;
1943 }
1944 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
1945 
1946 
1947 /* Compares an address/prefix_len with addresses on device @dev.
1948  * If one is found it returns true.
1949  */
1950 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1951 	const unsigned int prefix_len, struct net_device *dev)
1952 {
1953 	const struct inet6_ifaddr *ifa;
1954 	const struct inet6_dev *idev;
1955 	bool ret = false;
1956 
1957 	rcu_read_lock();
1958 	idev = __in6_dev_get(dev);
1959 	if (idev) {
1960 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1961 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
1962 			if (ret)
1963 				break;
1964 		}
1965 	}
1966 	rcu_read_unlock();
1967 
1968 	return ret;
1969 }
1970 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
1971 
1972 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
1973 {
1974 	const struct inet6_ifaddr *ifa;
1975 	const struct inet6_dev *idev;
1976 	int	onlink;
1977 
1978 	onlink = 0;
1979 	rcu_read_lock();
1980 	idev = __in6_dev_get(dev);
1981 	if (idev) {
1982 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
1983 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
1984 						   ifa->prefix_len);
1985 			if (onlink)
1986 				break;
1987 		}
1988 	}
1989 	rcu_read_unlock();
1990 	return onlink;
1991 }
1992 EXPORT_SYMBOL(ipv6_chk_prefix);
1993 
1994 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
1995 				     struct net_device *dev, int strict)
1996 {
1997 	unsigned int hash = inet6_addr_hash(net, addr);
1998 	struct inet6_ifaddr *ifp, *result = NULL;
1999 
2000 	rcu_read_lock();
2001 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
2002 		if (!net_eq(dev_net(ifp->idev->dev), net))
2003 			continue;
2004 		if (ipv6_addr_equal(&ifp->addr, addr)) {
2005 			if (!dev || ifp->idev->dev == dev ||
2006 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
2007 				result = ifp;
2008 				in6_ifa_hold(ifp);
2009 				break;
2010 			}
2011 		}
2012 	}
2013 	rcu_read_unlock();
2014 
2015 	return result;
2016 }
2017 
2018 /* Gets referenced address, destroys ifaddr */
2019 
2020 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
2021 {
2022 	if (dad_failed)
2023 		ifp->flags |= IFA_F_DADFAILED;
2024 
2025 	if (ifp->flags&IFA_F_TEMPORARY) {
2026 		struct inet6_ifaddr *ifpub;
2027 		spin_lock_bh(&ifp->lock);
2028 		ifpub = ifp->ifpub;
2029 		if (ifpub) {
2030 			in6_ifa_hold(ifpub);
2031 			spin_unlock_bh(&ifp->lock);
2032 			ipv6_create_tempaddr(ifpub, ifp, true);
2033 			in6_ifa_put(ifpub);
2034 		} else {
2035 			spin_unlock_bh(&ifp->lock);
2036 		}
2037 		ipv6_del_addr(ifp);
2038 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
2039 		spin_lock_bh(&ifp->lock);
2040 		addrconf_del_dad_work(ifp);
2041 		ifp->flags |= IFA_F_TENTATIVE;
2042 		if (dad_failed)
2043 			ifp->flags &= ~IFA_F_OPTIMISTIC;
2044 		spin_unlock_bh(&ifp->lock);
2045 		if (dad_failed)
2046 			ipv6_ifa_notify(0, ifp);
2047 		in6_ifa_put(ifp);
2048 	} else {
2049 		ipv6_del_addr(ifp);
2050 	}
2051 }
2052 
2053 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
2054 {
2055 	int err = -ENOENT;
2056 
2057 	spin_lock_bh(&ifp->lock);
2058 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
2059 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
2060 		err = 0;
2061 	}
2062 	spin_unlock_bh(&ifp->lock);
2063 
2064 	return err;
2065 }
2066 
2067 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp)
2068 {
2069 	struct inet6_dev *idev = ifp->idev;
2070 	struct net *net = dev_net(ifp->idev->dev);
2071 
2072 	if (addrconf_dad_end(ifp)) {
2073 		in6_ifa_put(ifp);
2074 		return;
2075 	}
2076 
2077 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c used by %pM detected!\n",
2078 			     ifp->idev->dev->name, &ifp->addr, eth_hdr(skb)->h_source);
2079 
2080 	spin_lock_bh(&ifp->lock);
2081 
2082 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2083 		struct in6_addr new_addr;
2084 		struct inet6_ifaddr *ifp2;
2085 		int retries = ifp->stable_privacy_retry + 1;
2086 		struct ifa6_config cfg = {
2087 			.pfx = &new_addr,
2088 			.plen = ifp->prefix_len,
2089 			.ifa_flags = ifp->flags,
2090 			.valid_lft = ifp->valid_lft,
2091 			.preferred_lft = ifp->prefered_lft,
2092 			.scope = ifp->scope,
2093 		};
2094 
2095 		if (retries > net->ipv6.sysctl.idgen_retries) {
2096 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2097 					     ifp->idev->dev->name);
2098 			goto errdad;
2099 		}
2100 
2101 		new_addr = ifp->addr;
2102 		if (ipv6_generate_stable_address(&new_addr, retries,
2103 						 idev))
2104 			goto errdad;
2105 
2106 		spin_unlock_bh(&ifp->lock);
2107 
2108 		if (idev->cnf.max_addresses &&
2109 		    ipv6_count_addresses(idev) >=
2110 		    idev->cnf.max_addresses)
2111 			goto lock_errdad;
2112 
2113 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2114 				     ifp->idev->dev->name);
2115 
2116 		ifp2 = ipv6_add_addr(idev, &cfg, false, NULL);
2117 		if (IS_ERR(ifp2))
2118 			goto lock_errdad;
2119 
2120 		spin_lock_bh(&ifp2->lock);
2121 		ifp2->stable_privacy_retry = retries;
2122 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2123 		spin_unlock_bh(&ifp2->lock);
2124 
2125 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2126 		in6_ifa_put(ifp2);
2127 lock_errdad:
2128 		spin_lock_bh(&ifp->lock);
2129 	}
2130 
2131 errdad:
2132 	/* transition from _POSTDAD to _ERRDAD */
2133 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2134 	spin_unlock_bh(&ifp->lock);
2135 
2136 	addrconf_mod_dad_work(ifp, 0);
2137 	in6_ifa_put(ifp);
2138 }
2139 
2140 /* Join to solicited addr multicast group.
2141  * caller must hold RTNL */
2142 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2143 {
2144 	struct in6_addr maddr;
2145 
2146 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2147 		return;
2148 
2149 	addrconf_addr_solict_mult(addr, &maddr);
2150 	ipv6_dev_mc_inc(dev, &maddr);
2151 }
2152 
2153 /* caller must hold RTNL */
2154 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2155 {
2156 	struct in6_addr maddr;
2157 
2158 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2159 		return;
2160 
2161 	addrconf_addr_solict_mult(addr, &maddr);
2162 	__ipv6_dev_mc_dec(idev, &maddr);
2163 }
2164 
2165 /* caller must hold RTNL */
2166 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2167 {
2168 	struct in6_addr addr;
2169 
2170 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2171 		return;
2172 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2173 	if (ipv6_addr_any(&addr))
2174 		return;
2175 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2176 }
2177 
2178 /* caller must hold RTNL */
2179 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2180 {
2181 	struct in6_addr addr;
2182 
2183 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2184 		return;
2185 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2186 	if (ipv6_addr_any(&addr))
2187 		return;
2188 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2189 }
2190 
2191 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2192 {
2193 	switch (dev->addr_len) {
2194 	case ETH_ALEN:
2195 		memcpy(eui, dev->dev_addr, 3);
2196 		eui[3] = 0xFF;
2197 		eui[4] = 0xFE;
2198 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2199 		break;
2200 	case EUI64_ADDR_LEN:
2201 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2202 		eui[0] ^= 2;
2203 		break;
2204 	default:
2205 		return -1;
2206 	}
2207 
2208 	return 0;
2209 }
2210 
2211 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2212 {
2213 	union fwnet_hwaddr *ha;
2214 
2215 	if (dev->addr_len != FWNET_ALEN)
2216 		return -1;
2217 
2218 	ha = (union fwnet_hwaddr *)dev->dev_addr;
2219 
2220 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2221 	eui[0] ^= 2;
2222 	return 0;
2223 }
2224 
2225 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2226 {
2227 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2228 	if (dev->addr_len != ARCNET_ALEN)
2229 		return -1;
2230 	memset(eui, 0, 7);
2231 	eui[7] = *(u8 *)dev->dev_addr;
2232 	return 0;
2233 }
2234 
2235 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2236 {
2237 	if (dev->addr_len != INFINIBAND_ALEN)
2238 		return -1;
2239 	memcpy(eui, dev->dev_addr + 12, 8);
2240 	eui[0] |= 2;
2241 	return 0;
2242 }
2243 
2244 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2245 {
2246 	if (addr == 0)
2247 		return -1;
2248 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2249 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2250 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2251 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2252 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2253 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2254 	eui[1] = 0;
2255 	eui[2] = 0x5E;
2256 	eui[3] = 0xFE;
2257 	memcpy(eui + 4, &addr, 4);
2258 	return 0;
2259 }
2260 
2261 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2262 {
2263 	if (dev->priv_flags & IFF_ISATAP)
2264 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2265 	return -1;
2266 }
2267 
2268 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2269 {
2270 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2271 }
2272 
2273 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2274 {
2275 	memcpy(eui, dev->perm_addr, 3);
2276 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2277 	eui[3] = 0xFF;
2278 	eui[4] = 0xFE;
2279 	eui[0] ^= 2;
2280 	return 0;
2281 }
2282 
2283 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2284 {
2285 	switch (dev->type) {
2286 	case ARPHRD_ETHER:
2287 	case ARPHRD_FDDI:
2288 		return addrconf_ifid_eui48(eui, dev);
2289 	case ARPHRD_ARCNET:
2290 		return addrconf_ifid_arcnet(eui, dev);
2291 	case ARPHRD_INFINIBAND:
2292 		return addrconf_ifid_infiniband(eui, dev);
2293 	case ARPHRD_SIT:
2294 		return addrconf_ifid_sit(eui, dev);
2295 	case ARPHRD_IPGRE:
2296 	case ARPHRD_TUNNEL:
2297 		return addrconf_ifid_gre(eui, dev);
2298 	case ARPHRD_6LOWPAN:
2299 		return addrconf_ifid_6lowpan(eui, dev);
2300 	case ARPHRD_IEEE1394:
2301 		return addrconf_ifid_ieee1394(eui, dev);
2302 	case ARPHRD_TUNNEL6:
2303 	case ARPHRD_IP6GRE:
2304 	case ARPHRD_RAWIP:
2305 		return addrconf_ifid_ip6tnl(eui, dev);
2306 	}
2307 	return -1;
2308 }
2309 
2310 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2311 {
2312 	int err = -1;
2313 	struct inet6_ifaddr *ifp;
2314 
2315 	read_lock_bh(&idev->lock);
2316 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2317 		if (ifp->scope > IFA_LINK)
2318 			break;
2319 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2320 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2321 			err = 0;
2322 			break;
2323 		}
2324 	}
2325 	read_unlock_bh(&idev->lock);
2326 	return err;
2327 }
2328 
2329 /* (re)generation of randomized interface identifier (RFC 3041 3.2, 3.5) */
2330 static void ipv6_regen_rndid(struct inet6_dev *idev)
2331 {
2332 regen:
2333 	get_random_bytes(idev->rndid, sizeof(idev->rndid));
2334 	idev->rndid[0] &= ~0x02;
2335 
2336 	/*
2337 	 * <draft-ietf-ipngwg-temp-addresses-v2-00.txt>:
2338 	 * check if generated address is not inappropriate
2339 	 *
2340 	 *  - Reserved subnet anycast (RFC 2526)
2341 	 *	11111101 11....11 1xxxxxxx
2342 	 *  - ISATAP (RFC4214) 6.1
2343 	 *	00-00-5E-FE-xx-xx-xx-xx
2344 	 *  - value 0
2345 	 *  - XXX: already assigned to an address on the device
2346 	 */
2347 	if (idev->rndid[0] == 0xfd &&
2348 	    (idev->rndid[1]&idev->rndid[2]&idev->rndid[3]&idev->rndid[4]&idev->rndid[5]&idev->rndid[6]) == 0xff &&
2349 	    (idev->rndid[7]&0x80))
2350 		goto regen;
2351 	if ((idev->rndid[0]|idev->rndid[1]) == 0) {
2352 		if (idev->rndid[2] == 0x5e && idev->rndid[3] == 0xfe)
2353 			goto regen;
2354 		if ((idev->rndid[2]|idev->rndid[3]|idev->rndid[4]|idev->rndid[5]|idev->rndid[6]|idev->rndid[7]) == 0x00)
2355 			goto regen;
2356 	}
2357 }
2358 
2359 static void  ipv6_try_regen_rndid(struct inet6_dev *idev, struct in6_addr *tmpaddr)
2360 {
2361 	if (tmpaddr && memcmp(idev->rndid, &tmpaddr->s6_addr[8], 8) == 0)
2362 		ipv6_regen_rndid(idev);
2363 }
2364 
2365 /*
2366  *	Add prefix route.
2367  */
2368 
2369 static void
2370 addrconf_prefix_route(struct in6_addr *pfx, int plen, u32 metric,
2371 		      struct net_device *dev, unsigned long expires,
2372 		      u32 flags, gfp_t gfp_flags)
2373 {
2374 	struct fib6_config cfg = {
2375 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2376 		.fc_metric = metric ? : IP6_RT_PRIO_ADDRCONF,
2377 		.fc_ifindex = dev->ifindex,
2378 		.fc_expires = expires,
2379 		.fc_dst_len = plen,
2380 		.fc_flags = RTF_UP | flags,
2381 		.fc_nlinfo.nl_net = dev_net(dev),
2382 		.fc_protocol = RTPROT_KERNEL,
2383 		.fc_type = RTN_UNICAST,
2384 	};
2385 
2386 	cfg.fc_dst = *pfx;
2387 
2388 	/* Prevent useless cloning on PtP SIT.
2389 	   This thing is done here expecting that the whole
2390 	   class of non-broadcast devices need not cloning.
2391 	 */
2392 #if IS_ENABLED(CONFIG_IPV6_SIT)
2393 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2394 		cfg.fc_flags |= RTF_NONEXTHOP;
2395 #endif
2396 
2397 	ip6_route_add(&cfg, gfp_flags, NULL);
2398 }
2399 
2400 
2401 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2402 						  int plen,
2403 						  const struct net_device *dev,
2404 						  u32 flags, u32 noflags,
2405 						  bool no_gw)
2406 {
2407 	struct fib6_node *fn;
2408 	struct fib6_info *rt = NULL;
2409 	struct fib6_table *table;
2410 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2411 
2412 	table = fib6_get_table(dev_net(dev), tb_id);
2413 	if (!table)
2414 		return NULL;
2415 
2416 	rcu_read_lock();
2417 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2418 	if (!fn)
2419 		goto out;
2420 
2421 	for_each_fib6_node_rt_rcu(fn) {
2422 		if (rt->fib6_nh.fib_nh_dev->ifindex != dev->ifindex)
2423 			continue;
2424 		if (no_gw && rt->fib6_nh.fib_nh_gw_family)
2425 			continue;
2426 		if ((rt->fib6_flags & flags) != flags)
2427 			continue;
2428 		if ((rt->fib6_flags & noflags) != 0)
2429 			continue;
2430 		if (!fib6_info_hold_safe(rt))
2431 			continue;
2432 		break;
2433 	}
2434 out:
2435 	rcu_read_unlock();
2436 	return rt;
2437 }
2438 
2439 
2440 /* Create "default" multicast route to the interface */
2441 
2442 static void addrconf_add_mroute(struct net_device *dev)
2443 {
2444 	struct fib6_config cfg = {
2445 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2446 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2447 		.fc_ifindex = dev->ifindex,
2448 		.fc_dst_len = 8,
2449 		.fc_flags = RTF_UP,
2450 		.fc_type = RTN_UNICAST,
2451 		.fc_nlinfo.nl_net = dev_net(dev),
2452 	};
2453 
2454 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2455 
2456 	ip6_route_add(&cfg, GFP_KERNEL, NULL);
2457 }
2458 
2459 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2460 {
2461 	struct inet6_dev *idev;
2462 
2463 	ASSERT_RTNL();
2464 
2465 	idev = ipv6_find_idev(dev);
2466 	if (!idev)
2467 		return ERR_PTR(-ENOBUFS);
2468 
2469 	if (idev->cnf.disable_ipv6)
2470 		return ERR_PTR(-EACCES);
2471 
2472 	/* Add default multicast route */
2473 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2474 		addrconf_add_mroute(dev);
2475 
2476 	return idev;
2477 }
2478 
2479 static void manage_tempaddrs(struct inet6_dev *idev,
2480 			     struct inet6_ifaddr *ifp,
2481 			     __u32 valid_lft, __u32 prefered_lft,
2482 			     bool create, unsigned long now)
2483 {
2484 	u32 flags;
2485 	struct inet6_ifaddr *ift;
2486 
2487 	read_lock_bh(&idev->lock);
2488 	/* update all temporary addresses in the list */
2489 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2490 		int age, max_valid, max_prefered;
2491 
2492 		if (ifp != ift->ifpub)
2493 			continue;
2494 
2495 		/* RFC 4941 section 3.3:
2496 		 * If a received option will extend the lifetime of a public
2497 		 * address, the lifetimes of temporary addresses should
2498 		 * be extended, subject to the overall constraint that no
2499 		 * temporary addresses should ever remain "valid" or "preferred"
2500 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2501 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2502 		 */
2503 		age = (now - ift->cstamp) / HZ;
2504 		max_valid = idev->cnf.temp_valid_lft - age;
2505 		if (max_valid < 0)
2506 			max_valid = 0;
2507 
2508 		max_prefered = idev->cnf.temp_prefered_lft -
2509 			       idev->desync_factor - age;
2510 		if (max_prefered < 0)
2511 			max_prefered = 0;
2512 
2513 		if (valid_lft > max_valid)
2514 			valid_lft = max_valid;
2515 
2516 		if (prefered_lft > max_prefered)
2517 			prefered_lft = max_prefered;
2518 
2519 		spin_lock(&ift->lock);
2520 		flags = ift->flags;
2521 		ift->valid_lft = valid_lft;
2522 		ift->prefered_lft = prefered_lft;
2523 		ift->tstamp = now;
2524 		if (prefered_lft > 0)
2525 			ift->flags &= ~IFA_F_DEPRECATED;
2526 
2527 		spin_unlock(&ift->lock);
2528 		if (!(flags&IFA_F_TENTATIVE))
2529 			ipv6_ifa_notify(0, ift);
2530 	}
2531 
2532 	if ((create || list_empty(&idev->tempaddr_list)) &&
2533 	    idev->cnf.use_tempaddr > 0) {
2534 		/* When a new public address is created as described
2535 		 * in [ADDRCONF], also create a new temporary address.
2536 		 * Also create a temporary address if it's enabled but
2537 		 * no temporary address currently exists.
2538 		 */
2539 		read_unlock_bh(&idev->lock);
2540 		ipv6_create_tempaddr(ifp, NULL, false);
2541 	} else {
2542 		read_unlock_bh(&idev->lock);
2543 	}
2544 }
2545 
2546 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2547 {
2548 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2549 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2550 }
2551 
2552 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2553 				 const struct prefix_info *pinfo,
2554 				 struct inet6_dev *in6_dev,
2555 				 const struct in6_addr *addr, int addr_type,
2556 				 u32 addr_flags, bool sllao, bool tokenized,
2557 				 __u32 valid_lft, u32 prefered_lft)
2558 {
2559 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2560 	int create = 0, update_lft = 0;
2561 
2562 	if (!ifp && valid_lft) {
2563 		int max_addresses = in6_dev->cnf.max_addresses;
2564 		struct ifa6_config cfg = {
2565 			.pfx = addr,
2566 			.plen = pinfo->prefix_len,
2567 			.ifa_flags = addr_flags,
2568 			.valid_lft = valid_lft,
2569 			.preferred_lft = prefered_lft,
2570 			.scope = addr_type & IPV6_ADDR_SCOPE_MASK,
2571 		};
2572 
2573 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2574 		if ((net->ipv6.devconf_all->optimistic_dad ||
2575 		     in6_dev->cnf.optimistic_dad) &&
2576 		    !net->ipv6.devconf_all->forwarding && sllao)
2577 			cfg.ifa_flags |= IFA_F_OPTIMISTIC;
2578 #endif
2579 
2580 		/* Do not allow to create too much of autoconfigured
2581 		 * addresses; this would be too easy way to crash kernel.
2582 		 */
2583 		if (!max_addresses ||
2584 		    ipv6_count_addresses(in6_dev) < max_addresses)
2585 			ifp = ipv6_add_addr(in6_dev, &cfg, false, NULL);
2586 
2587 		if (IS_ERR_OR_NULL(ifp))
2588 			return -1;
2589 
2590 		create = 1;
2591 		spin_lock_bh(&ifp->lock);
2592 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2593 		ifp->cstamp = jiffies;
2594 		ifp->tokenized = tokenized;
2595 		spin_unlock_bh(&ifp->lock);
2596 		addrconf_dad_start(ifp);
2597 	}
2598 
2599 	if (ifp) {
2600 		u32 flags;
2601 		unsigned long now;
2602 		u32 stored_lft;
2603 
2604 		/* update lifetime (RFC2462 5.5.3 e) */
2605 		spin_lock_bh(&ifp->lock);
2606 		now = jiffies;
2607 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2608 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2609 		else
2610 			stored_lft = 0;
2611 		if (!create && stored_lft) {
2612 			const u32 minimum_lft = min_t(u32,
2613 				stored_lft, MIN_VALID_LIFETIME);
2614 			valid_lft = max(valid_lft, minimum_lft);
2615 
2616 			/* RFC4862 Section 5.5.3e:
2617 			 * "Note that the preferred lifetime of the
2618 			 *  corresponding address is always reset to
2619 			 *  the Preferred Lifetime in the received
2620 			 *  Prefix Information option, regardless of
2621 			 *  whether the valid lifetime is also reset or
2622 			 *  ignored."
2623 			 *
2624 			 * So we should always update prefered_lft here.
2625 			 */
2626 			update_lft = 1;
2627 		}
2628 
2629 		if (update_lft) {
2630 			ifp->valid_lft = valid_lft;
2631 			ifp->prefered_lft = prefered_lft;
2632 			ifp->tstamp = now;
2633 			flags = ifp->flags;
2634 			ifp->flags &= ~IFA_F_DEPRECATED;
2635 			spin_unlock_bh(&ifp->lock);
2636 
2637 			if (!(flags&IFA_F_TENTATIVE))
2638 				ipv6_ifa_notify(0, ifp);
2639 		} else
2640 			spin_unlock_bh(&ifp->lock);
2641 
2642 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2643 				 create, now);
2644 
2645 		in6_ifa_put(ifp);
2646 		addrconf_verify();
2647 	}
2648 
2649 	return 0;
2650 }
2651 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2652 
2653 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2654 {
2655 	struct prefix_info *pinfo;
2656 	__u32 valid_lft;
2657 	__u32 prefered_lft;
2658 	int addr_type, err;
2659 	u32 addr_flags = 0;
2660 	struct inet6_dev *in6_dev;
2661 	struct net *net = dev_net(dev);
2662 
2663 	pinfo = (struct prefix_info *) opt;
2664 
2665 	if (len < sizeof(struct prefix_info)) {
2666 		netdev_dbg(dev, "addrconf: prefix option too short\n");
2667 		return;
2668 	}
2669 
2670 	/*
2671 	 *	Validation checks ([ADDRCONF], page 19)
2672 	 */
2673 
2674 	addr_type = ipv6_addr_type(&pinfo->prefix);
2675 
2676 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2677 		return;
2678 
2679 	valid_lft = ntohl(pinfo->valid);
2680 	prefered_lft = ntohl(pinfo->prefered);
2681 
2682 	if (prefered_lft > valid_lft) {
2683 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2684 		return;
2685 	}
2686 
2687 	in6_dev = in6_dev_get(dev);
2688 
2689 	if (!in6_dev) {
2690 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2691 				    dev->name);
2692 		return;
2693 	}
2694 
2695 	/*
2696 	 *	Two things going on here:
2697 	 *	1) Add routes for on-link prefixes
2698 	 *	2) Configure prefixes with the auto flag set
2699 	 */
2700 
2701 	if (pinfo->onlink) {
2702 		struct fib6_info *rt;
2703 		unsigned long rt_expires;
2704 
2705 		/* Avoid arithmetic overflow. Really, we could
2706 		 * save rt_expires in seconds, likely valid_lft,
2707 		 * but it would require division in fib gc, that it
2708 		 * not good.
2709 		 */
2710 		if (HZ > USER_HZ)
2711 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2712 		else
2713 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2714 
2715 		if (addrconf_finite_timeout(rt_expires))
2716 			rt_expires *= HZ;
2717 
2718 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2719 					       pinfo->prefix_len,
2720 					       dev,
2721 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2722 					       RTF_DEFAULT, true);
2723 
2724 		if (rt) {
2725 			/* Autoconf prefix route */
2726 			if (valid_lft == 0) {
2727 				ip6_del_rt(net, rt);
2728 				rt = NULL;
2729 			} else if (addrconf_finite_timeout(rt_expires)) {
2730 				/* not infinity */
2731 				fib6_set_expires(rt, jiffies + rt_expires);
2732 			} else {
2733 				fib6_clean_expires(rt);
2734 			}
2735 		} else if (valid_lft) {
2736 			clock_t expires = 0;
2737 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2738 			if (addrconf_finite_timeout(rt_expires)) {
2739 				/* not infinity */
2740 				flags |= RTF_EXPIRES;
2741 				expires = jiffies_to_clock_t(rt_expires);
2742 			}
2743 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2744 					      0, dev, expires, flags,
2745 					      GFP_ATOMIC);
2746 		}
2747 		fib6_info_release(rt);
2748 	}
2749 
2750 	/* Try to figure out our local address for this prefix */
2751 
2752 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2753 		struct in6_addr addr;
2754 		bool tokenized = false, dev_addr_generated = false;
2755 
2756 		if (pinfo->prefix_len == 64) {
2757 			memcpy(&addr, &pinfo->prefix, 8);
2758 
2759 			if (!ipv6_addr_any(&in6_dev->token)) {
2760 				read_lock_bh(&in6_dev->lock);
2761 				memcpy(addr.s6_addr + 8,
2762 				       in6_dev->token.s6_addr + 8, 8);
2763 				read_unlock_bh(&in6_dev->lock);
2764 				tokenized = true;
2765 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2766 				   !ipv6_generate_stable_address(&addr, 0,
2767 								 in6_dev)) {
2768 				addr_flags |= IFA_F_STABLE_PRIVACY;
2769 				goto ok;
2770 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2771 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2772 				goto put;
2773 			} else {
2774 				dev_addr_generated = true;
2775 			}
2776 			goto ok;
2777 		}
2778 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2779 				    pinfo->prefix_len);
2780 		goto put;
2781 
2782 ok:
2783 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2784 						   &addr, addr_type,
2785 						   addr_flags, sllao,
2786 						   tokenized, valid_lft,
2787 						   prefered_lft);
2788 		if (err)
2789 			goto put;
2790 
2791 		/* Ignore error case here because previous prefix add addr was
2792 		 * successful which will be notified.
2793 		 */
2794 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2795 					      addr_type, addr_flags, sllao,
2796 					      tokenized, valid_lft,
2797 					      prefered_lft,
2798 					      dev_addr_generated);
2799 	}
2800 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2801 put:
2802 	in6_dev_put(in6_dev);
2803 }
2804 
2805 /*
2806  *	Set destination address.
2807  *	Special case for SIT interfaces where we create a new "virtual"
2808  *	device.
2809  */
2810 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2811 {
2812 	struct in6_ifreq ireq;
2813 	struct net_device *dev;
2814 	int err = -EINVAL;
2815 
2816 	rtnl_lock();
2817 
2818 	err = -EFAULT;
2819 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2820 		goto err_exit;
2821 
2822 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2823 
2824 	err = -ENODEV;
2825 	if (!dev)
2826 		goto err_exit;
2827 
2828 #if IS_ENABLED(CONFIG_IPV6_SIT)
2829 	if (dev->type == ARPHRD_SIT) {
2830 		const struct net_device_ops *ops = dev->netdev_ops;
2831 		struct ifreq ifr;
2832 		struct ip_tunnel_parm p;
2833 
2834 		err = -EADDRNOTAVAIL;
2835 		if (!(ipv6_addr_type(&ireq.ifr6_addr) & IPV6_ADDR_COMPATv4))
2836 			goto err_exit;
2837 
2838 		memset(&p, 0, sizeof(p));
2839 		p.iph.daddr = ireq.ifr6_addr.s6_addr32[3];
2840 		p.iph.saddr = 0;
2841 		p.iph.version = 4;
2842 		p.iph.ihl = 5;
2843 		p.iph.protocol = IPPROTO_IPV6;
2844 		p.iph.ttl = 64;
2845 		ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
2846 
2847 		if (ops->ndo_do_ioctl) {
2848 			mm_segment_t oldfs = get_fs();
2849 
2850 			set_fs(KERNEL_DS);
2851 			err = ops->ndo_do_ioctl(dev, &ifr, SIOCADDTUNNEL);
2852 			set_fs(oldfs);
2853 		} else
2854 			err = -EOPNOTSUPP;
2855 
2856 		if (err == 0) {
2857 			err = -ENOBUFS;
2858 			dev = __dev_get_by_name(net, p.name);
2859 			if (!dev)
2860 				goto err_exit;
2861 			err = dev_open(dev, NULL);
2862 		}
2863 	}
2864 #endif
2865 
2866 err_exit:
2867 	rtnl_unlock();
2868 	return err;
2869 }
2870 
2871 static int ipv6_mc_config(struct sock *sk, bool join,
2872 			  const struct in6_addr *addr, int ifindex)
2873 {
2874 	int ret;
2875 
2876 	ASSERT_RTNL();
2877 
2878 	lock_sock(sk);
2879 	if (join)
2880 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2881 	else
2882 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2883 	release_sock(sk);
2884 
2885 	return ret;
2886 }
2887 
2888 /*
2889  *	Manual configuration of address on an interface
2890  */
2891 static int inet6_addr_add(struct net *net, int ifindex,
2892 			  struct ifa6_config *cfg,
2893 			  struct netlink_ext_ack *extack)
2894 {
2895 	struct inet6_ifaddr *ifp;
2896 	struct inet6_dev *idev;
2897 	struct net_device *dev;
2898 	unsigned long timeout;
2899 	clock_t expires;
2900 	u32 flags;
2901 
2902 	ASSERT_RTNL();
2903 
2904 	if (cfg->plen > 128)
2905 		return -EINVAL;
2906 
2907 	/* check the lifetime */
2908 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
2909 		return -EINVAL;
2910 
2911 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR && cfg->plen != 64)
2912 		return -EINVAL;
2913 
2914 	dev = __dev_get_by_index(net, ifindex);
2915 	if (!dev)
2916 		return -ENODEV;
2917 
2918 	idev = addrconf_add_dev(dev);
2919 	if (IS_ERR(idev))
2920 		return PTR_ERR(idev);
2921 
2922 	if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2923 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2924 					 true, cfg->pfx, ifindex);
2925 
2926 		if (ret < 0)
2927 			return ret;
2928 	}
2929 
2930 	cfg->scope = ipv6_addr_scope(cfg->pfx);
2931 
2932 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
2933 	if (addrconf_finite_timeout(timeout)) {
2934 		expires = jiffies_to_clock_t(timeout * HZ);
2935 		cfg->valid_lft = timeout;
2936 		flags = RTF_EXPIRES;
2937 	} else {
2938 		expires = 0;
2939 		flags = 0;
2940 		cfg->ifa_flags |= IFA_F_PERMANENT;
2941 	}
2942 
2943 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
2944 	if (addrconf_finite_timeout(timeout)) {
2945 		if (timeout == 0)
2946 			cfg->ifa_flags |= IFA_F_DEPRECATED;
2947 		cfg->preferred_lft = timeout;
2948 	}
2949 
2950 	ifp = ipv6_add_addr(idev, cfg, true, extack);
2951 	if (!IS_ERR(ifp)) {
2952 		if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
2953 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
2954 					      ifp->rt_priority, dev, expires,
2955 					      flags, GFP_KERNEL);
2956 		}
2957 
2958 		/* Send a netlink notification if DAD is enabled and
2959 		 * optimistic flag is not set
2960 		 */
2961 		if (!(ifp->flags & (IFA_F_OPTIMISTIC | IFA_F_NODAD)))
2962 			ipv6_ifa_notify(0, ifp);
2963 		/*
2964 		 * Note that section 3.1 of RFC 4429 indicates
2965 		 * that the Optimistic flag should not be set for
2966 		 * manually configured addresses
2967 		 */
2968 		addrconf_dad_start(ifp);
2969 		if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR)
2970 			manage_tempaddrs(idev, ifp, cfg->valid_lft,
2971 					 cfg->preferred_lft, true, jiffies);
2972 		in6_ifa_put(ifp);
2973 		addrconf_verify_rtnl();
2974 		return 0;
2975 	} else if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2976 		ipv6_mc_config(net->ipv6.mc_autojoin_sk, false,
2977 			       cfg->pfx, ifindex);
2978 	}
2979 
2980 	return PTR_ERR(ifp);
2981 }
2982 
2983 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
2984 			  const struct in6_addr *pfx, unsigned int plen)
2985 {
2986 	struct inet6_ifaddr *ifp;
2987 	struct inet6_dev *idev;
2988 	struct net_device *dev;
2989 
2990 	if (plen > 128)
2991 		return -EINVAL;
2992 
2993 	dev = __dev_get_by_index(net, ifindex);
2994 	if (!dev)
2995 		return -ENODEV;
2996 
2997 	idev = __in6_dev_get(dev);
2998 	if (!idev)
2999 		return -ENXIO;
3000 
3001 	read_lock_bh(&idev->lock);
3002 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3003 		if (ifp->prefix_len == plen &&
3004 		    ipv6_addr_equal(pfx, &ifp->addr)) {
3005 			in6_ifa_hold(ifp);
3006 			read_unlock_bh(&idev->lock);
3007 
3008 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
3009 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
3010 				manage_tempaddrs(idev, ifp, 0, 0, false,
3011 						 jiffies);
3012 			ipv6_del_addr(ifp);
3013 			addrconf_verify_rtnl();
3014 			if (ipv6_addr_is_multicast(pfx)) {
3015 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3016 					       false, pfx, dev->ifindex);
3017 			}
3018 			return 0;
3019 		}
3020 	}
3021 	read_unlock_bh(&idev->lock);
3022 	return -EADDRNOTAVAIL;
3023 }
3024 
3025 
3026 int addrconf_add_ifaddr(struct net *net, void __user *arg)
3027 {
3028 	struct ifa6_config cfg = {
3029 		.ifa_flags = IFA_F_PERMANENT,
3030 		.preferred_lft = INFINITY_LIFE_TIME,
3031 		.valid_lft = INFINITY_LIFE_TIME,
3032 	};
3033 	struct in6_ifreq ireq;
3034 	int err;
3035 
3036 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3037 		return -EPERM;
3038 
3039 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3040 		return -EFAULT;
3041 
3042 	cfg.pfx = &ireq.ifr6_addr;
3043 	cfg.plen = ireq.ifr6_prefixlen;
3044 
3045 	rtnl_lock();
3046 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &cfg, NULL);
3047 	rtnl_unlock();
3048 	return err;
3049 }
3050 
3051 int addrconf_del_ifaddr(struct net *net, void __user *arg)
3052 {
3053 	struct in6_ifreq ireq;
3054 	int err;
3055 
3056 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3057 		return -EPERM;
3058 
3059 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3060 		return -EFAULT;
3061 
3062 	rtnl_lock();
3063 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
3064 			     ireq.ifr6_prefixlen);
3065 	rtnl_unlock();
3066 	return err;
3067 }
3068 
3069 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
3070 		     int plen, int scope)
3071 {
3072 	struct inet6_ifaddr *ifp;
3073 	struct ifa6_config cfg = {
3074 		.pfx = addr,
3075 		.plen = plen,
3076 		.ifa_flags = IFA_F_PERMANENT,
3077 		.valid_lft = INFINITY_LIFE_TIME,
3078 		.preferred_lft = INFINITY_LIFE_TIME,
3079 		.scope = scope
3080 	};
3081 
3082 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3083 	if (!IS_ERR(ifp)) {
3084 		spin_lock_bh(&ifp->lock);
3085 		ifp->flags &= ~IFA_F_TENTATIVE;
3086 		spin_unlock_bh(&ifp->lock);
3087 		rt_genid_bump_ipv6(dev_net(idev->dev));
3088 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3089 		in6_ifa_put(ifp);
3090 	}
3091 }
3092 
3093 #if IS_ENABLED(CONFIG_IPV6_SIT)
3094 static void sit_add_v4_addrs(struct inet6_dev *idev)
3095 {
3096 	struct in6_addr addr;
3097 	struct net_device *dev;
3098 	struct net *net = dev_net(idev->dev);
3099 	int scope, plen;
3100 	u32 pflags = 0;
3101 
3102 	ASSERT_RTNL();
3103 
3104 	memset(&addr, 0, sizeof(struct in6_addr));
3105 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr, 4);
3106 
3107 	if (idev->dev->flags&IFF_POINTOPOINT) {
3108 		addr.s6_addr32[0] = htonl(0xfe800000);
3109 		scope = IFA_LINK;
3110 		plen = 64;
3111 	} else {
3112 		scope = IPV6_ADDR_COMPATv4;
3113 		plen = 96;
3114 		pflags |= RTF_NONEXTHOP;
3115 	}
3116 
3117 	if (addr.s6_addr32[3]) {
3118 		add_addr(idev, &addr, plen, scope);
3119 		addrconf_prefix_route(&addr, plen, 0, idev->dev, 0, pflags,
3120 				      GFP_KERNEL);
3121 		return;
3122 	}
3123 
3124 	for_each_netdev(net, dev) {
3125 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3126 		if (in_dev && (dev->flags & IFF_UP)) {
3127 			struct in_ifaddr *ifa;
3128 
3129 			int flag = scope;
3130 
3131 			for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
3132 
3133 				addr.s6_addr32[3] = ifa->ifa_local;
3134 
3135 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3136 					continue;
3137 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3138 					if (idev->dev->flags&IFF_POINTOPOINT)
3139 						continue;
3140 					flag |= IFA_HOST;
3141 				}
3142 
3143 				add_addr(idev, &addr, plen, flag);
3144 				addrconf_prefix_route(&addr, plen, 0, idev->dev,
3145 						      0, pflags, GFP_KERNEL);
3146 			}
3147 		}
3148 	}
3149 }
3150 #endif
3151 
3152 static void init_loopback(struct net_device *dev)
3153 {
3154 	struct inet6_dev  *idev;
3155 
3156 	/* ::1 */
3157 
3158 	ASSERT_RTNL();
3159 
3160 	idev = ipv6_find_idev(dev);
3161 	if (!idev) {
3162 		pr_debug("%s: add_dev failed\n", __func__);
3163 		return;
3164 	}
3165 
3166 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST);
3167 }
3168 
3169 void addrconf_add_linklocal(struct inet6_dev *idev,
3170 			    const struct in6_addr *addr, u32 flags)
3171 {
3172 	struct ifa6_config cfg = {
3173 		.pfx = addr,
3174 		.plen = 64,
3175 		.ifa_flags = flags | IFA_F_PERMANENT,
3176 		.valid_lft = INFINITY_LIFE_TIME,
3177 		.preferred_lft = INFINITY_LIFE_TIME,
3178 		.scope = IFA_LINK
3179 	};
3180 	struct inet6_ifaddr *ifp;
3181 
3182 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3183 	if ((dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad ||
3184 	     idev->cnf.optimistic_dad) &&
3185 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3186 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
3187 #endif
3188 
3189 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3190 	if (!IS_ERR(ifp)) {
3191 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, 0, idev->dev,
3192 				      0, 0, GFP_ATOMIC);
3193 		addrconf_dad_start(ifp);
3194 		in6_ifa_put(ifp);
3195 	}
3196 }
3197 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3198 
3199 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3200 {
3201 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3202 		return true;
3203 
3204 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3205 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3206 		return true;
3207 
3208 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3209 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3210 		return true;
3211 
3212 	return false;
3213 }
3214 
3215 static int ipv6_generate_stable_address(struct in6_addr *address,
3216 					u8 dad_count,
3217 					const struct inet6_dev *idev)
3218 {
3219 	static DEFINE_SPINLOCK(lock);
3220 	static __u32 digest[SHA_DIGEST_WORDS];
3221 	static __u32 workspace[SHA_WORKSPACE_WORDS];
3222 
3223 	static union {
3224 		char __data[SHA_MESSAGE_BYTES];
3225 		struct {
3226 			struct in6_addr secret;
3227 			__be32 prefix[2];
3228 			unsigned char hwaddr[MAX_ADDR_LEN];
3229 			u8 dad_count;
3230 		} __packed;
3231 	} data;
3232 
3233 	struct in6_addr secret;
3234 	struct in6_addr temp;
3235 	struct net *net = dev_net(idev->dev);
3236 
3237 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3238 
3239 	if (idev->cnf.stable_secret.initialized)
3240 		secret = idev->cnf.stable_secret.secret;
3241 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3242 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3243 	else
3244 		return -1;
3245 
3246 retry:
3247 	spin_lock_bh(&lock);
3248 
3249 	sha_init(digest);
3250 	memset(&data, 0, sizeof(data));
3251 	memset(workspace, 0, sizeof(workspace));
3252 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3253 	data.prefix[0] = address->s6_addr32[0];
3254 	data.prefix[1] = address->s6_addr32[1];
3255 	data.secret = secret;
3256 	data.dad_count = dad_count;
3257 
3258 	sha_transform(digest, data.__data, workspace);
3259 
3260 	temp = *address;
3261 	temp.s6_addr32[2] = (__force __be32)digest[0];
3262 	temp.s6_addr32[3] = (__force __be32)digest[1];
3263 
3264 	spin_unlock_bh(&lock);
3265 
3266 	if (ipv6_reserved_interfaceid(temp)) {
3267 		dad_count++;
3268 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3269 			return -1;
3270 		goto retry;
3271 	}
3272 
3273 	*address = temp;
3274 	return 0;
3275 }
3276 
3277 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3278 {
3279 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3280 
3281 	if (s->initialized)
3282 		return;
3283 	s = &idev->cnf.stable_secret;
3284 	get_random_bytes(&s->secret, sizeof(s->secret));
3285 	s->initialized = true;
3286 }
3287 
3288 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3289 {
3290 	struct in6_addr addr;
3291 
3292 	/* no link local addresses on L3 master devices */
3293 	if (netif_is_l3_master(idev->dev))
3294 		return;
3295 
3296 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3297 
3298 	switch (idev->cnf.addr_gen_mode) {
3299 	case IN6_ADDR_GEN_MODE_RANDOM:
3300 		ipv6_gen_mode_random_init(idev);
3301 		/* fallthrough */
3302 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3303 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3304 			addrconf_add_linklocal(idev, &addr,
3305 					       IFA_F_STABLE_PRIVACY);
3306 		else if (prefix_route)
3307 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3308 					      0, 0, GFP_KERNEL);
3309 		break;
3310 	case IN6_ADDR_GEN_MODE_EUI64:
3311 		/* addrconf_add_linklocal also adds a prefix_route and we
3312 		 * only need to care about prefix routes if ipv6_generate_eui64
3313 		 * couldn't generate one.
3314 		 */
3315 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3316 			addrconf_add_linklocal(idev, &addr, 0);
3317 		else if (prefix_route)
3318 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3319 					      0, 0, GFP_KERNEL);
3320 		break;
3321 	case IN6_ADDR_GEN_MODE_NONE:
3322 	default:
3323 		/* will not add any link local address */
3324 		break;
3325 	}
3326 }
3327 
3328 static void addrconf_dev_config(struct net_device *dev)
3329 {
3330 	struct inet6_dev *idev;
3331 
3332 	ASSERT_RTNL();
3333 
3334 	if ((dev->type != ARPHRD_ETHER) &&
3335 	    (dev->type != ARPHRD_FDDI) &&
3336 	    (dev->type != ARPHRD_ARCNET) &&
3337 	    (dev->type != ARPHRD_INFINIBAND) &&
3338 	    (dev->type != ARPHRD_IEEE1394) &&
3339 	    (dev->type != ARPHRD_TUNNEL6) &&
3340 	    (dev->type != ARPHRD_6LOWPAN) &&
3341 	    (dev->type != ARPHRD_IP6GRE) &&
3342 	    (dev->type != ARPHRD_IPGRE) &&
3343 	    (dev->type != ARPHRD_TUNNEL) &&
3344 	    (dev->type != ARPHRD_NONE) &&
3345 	    (dev->type != ARPHRD_RAWIP)) {
3346 		/* Alas, we support only Ethernet autoconfiguration. */
3347 		return;
3348 	}
3349 
3350 	idev = addrconf_add_dev(dev);
3351 	if (IS_ERR(idev))
3352 		return;
3353 
3354 	/* this device type has no EUI support */
3355 	if (dev->type == ARPHRD_NONE &&
3356 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3357 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_RANDOM;
3358 
3359 	addrconf_addr_gen(idev, false);
3360 }
3361 
3362 #if IS_ENABLED(CONFIG_IPV6_SIT)
3363 static void addrconf_sit_config(struct net_device *dev)
3364 {
3365 	struct inet6_dev *idev;
3366 
3367 	ASSERT_RTNL();
3368 
3369 	/*
3370 	 * Configure the tunnel with one of our IPv4
3371 	 * addresses... we should configure all of
3372 	 * our v4 addrs in the tunnel
3373 	 */
3374 
3375 	idev = ipv6_find_idev(dev);
3376 	if (!idev) {
3377 		pr_debug("%s: add_dev failed\n", __func__);
3378 		return;
3379 	}
3380 
3381 	if (dev->priv_flags & IFF_ISATAP) {
3382 		addrconf_addr_gen(idev, false);
3383 		return;
3384 	}
3385 
3386 	sit_add_v4_addrs(idev);
3387 
3388 	if (dev->flags&IFF_POINTOPOINT)
3389 		addrconf_add_mroute(dev);
3390 }
3391 #endif
3392 
3393 #if IS_ENABLED(CONFIG_NET_IPGRE)
3394 static void addrconf_gre_config(struct net_device *dev)
3395 {
3396 	struct inet6_dev *idev;
3397 
3398 	ASSERT_RTNL();
3399 
3400 	idev = ipv6_find_idev(dev);
3401 	if (!idev) {
3402 		pr_debug("%s: add_dev failed\n", __func__);
3403 		return;
3404 	}
3405 
3406 	addrconf_addr_gen(idev, true);
3407 	if (dev->flags & IFF_POINTOPOINT)
3408 		addrconf_add_mroute(dev);
3409 }
3410 #endif
3411 
3412 static int fixup_permanent_addr(struct net *net,
3413 				struct inet6_dev *idev,
3414 				struct inet6_ifaddr *ifp)
3415 {
3416 	/* !fib6_node means the host route was removed from the
3417 	 * FIB, for example, if 'lo' device is taken down. In that
3418 	 * case regenerate the host route.
3419 	 */
3420 	if (!ifp->rt || !ifp->rt->fib6_node) {
3421 		struct fib6_info *f6i, *prev;
3422 
3423 		f6i = addrconf_f6i_alloc(net, idev, &ifp->addr, false,
3424 					 GFP_ATOMIC);
3425 		if (IS_ERR(f6i))
3426 			return PTR_ERR(f6i);
3427 
3428 		/* ifp->rt can be accessed outside of rtnl */
3429 		spin_lock(&ifp->lock);
3430 		prev = ifp->rt;
3431 		ifp->rt = f6i;
3432 		spin_unlock(&ifp->lock);
3433 
3434 		fib6_info_release(prev);
3435 	}
3436 
3437 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3438 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3439 				      ifp->rt_priority, idev->dev, 0, 0,
3440 				      GFP_ATOMIC);
3441 	}
3442 
3443 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3444 		addrconf_dad_start(ifp);
3445 
3446 	return 0;
3447 }
3448 
3449 static void addrconf_permanent_addr(struct net *net, struct net_device *dev)
3450 {
3451 	struct inet6_ifaddr *ifp, *tmp;
3452 	struct inet6_dev *idev;
3453 
3454 	idev = __in6_dev_get(dev);
3455 	if (!idev)
3456 		return;
3457 
3458 	write_lock_bh(&idev->lock);
3459 
3460 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3461 		if ((ifp->flags & IFA_F_PERMANENT) &&
3462 		    fixup_permanent_addr(net, idev, ifp) < 0) {
3463 			write_unlock_bh(&idev->lock);
3464 			in6_ifa_hold(ifp);
3465 			ipv6_del_addr(ifp);
3466 			write_lock_bh(&idev->lock);
3467 
3468 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3469 					     idev->dev->name, &ifp->addr);
3470 		}
3471 	}
3472 
3473 	write_unlock_bh(&idev->lock);
3474 }
3475 
3476 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3477 			   void *ptr)
3478 {
3479 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3480 	struct netdev_notifier_change_info *change_info;
3481 	struct netdev_notifier_changeupper_info *info;
3482 	struct inet6_dev *idev = __in6_dev_get(dev);
3483 	struct net *net = dev_net(dev);
3484 	int run_pending = 0;
3485 	int err;
3486 
3487 	switch (event) {
3488 	case NETDEV_REGISTER:
3489 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3490 			idev = ipv6_add_dev(dev);
3491 			if (IS_ERR(idev))
3492 				return notifier_from_errno(PTR_ERR(idev));
3493 		}
3494 		break;
3495 
3496 	case NETDEV_CHANGEMTU:
3497 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3498 		if (dev->mtu < IPV6_MIN_MTU) {
3499 			addrconf_ifdown(dev, dev != net->loopback_dev);
3500 			break;
3501 		}
3502 
3503 		if (idev) {
3504 			rt6_mtu_change(dev, dev->mtu);
3505 			idev->cnf.mtu6 = dev->mtu;
3506 			break;
3507 		}
3508 
3509 		/* allocate new idev */
3510 		idev = ipv6_add_dev(dev);
3511 		if (IS_ERR(idev))
3512 			break;
3513 
3514 		/* device is still not ready */
3515 		if (!(idev->if_flags & IF_READY))
3516 			break;
3517 
3518 		run_pending = 1;
3519 
3520 		/* fall through */
3521 
3522 	case NETDEV_UP:
3523 	case NETDEV_CHANGE:
3524 		if (dev->flags & IFF_SLAVE)
3525 			break;
3526 
3527 		if (idev && idev->cnf.disable_ipv6)
3528 			break;
3529 
3530 		if (event == NETDEV_UP) {
3531 			/* restore routes for permanent addresses */
3532 			addrconf_permanent_addr(net, dev);
3533 
3534 			if (!addrconf_link_ready(dev)) {
3535 				/* device is not ready yet. */
3536 				pr_debug("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3537 					 dev->name);
3538 				break;
3539 			}
3540 
3541 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3542 				idev = ipv6_add_dev(dev);
3543 
3544 			if (!IS_ERR_OR_NULL(idev)) {
3545 				idev->if_flags |= IF_READY;
3546 				run_pending = 1;
3547 			}
3548 		} else if (event == NETDEV_CHANGE) {
3549 			if (!addrconf_link_ready(dev)) {
3550 				/* device is still not ready. */
3551 				rt6_sync_down_dev(dev, event);
3552 				break;
3553 			}
3554 
3555 			if (!IS_ERR_OR_NULL(idev)) {
3556 				if (idev->if_flags & IF_READY) {
3557 					/* device is already configured -
3558 					 * but resend MLD reports, we might
3559 					 * have roamed and need to update
3560 					 * multicast snooping switches
3561 					 */
3562 					ipv6_mc_up(idev);
3563 					change_info = ptr;
3564 					if (change_info->flags_changed & IFF_NOARP)
3565 						addrconf_dad_run(idev, true);
3566 					rt6_sync_up(dev, RTNH_F_LINKDOWN);
3567 					break;
3568 				}
3569 				idev->if_flags |= IF_READY;
3570 			}
3571 
3572 			pr_info("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3573 				dev->name);
3574 
3575 			run_pending = 1;
3576 		}
3577 
3578 		switch (dev->type) {
3579 #if IS_ENABLED(CONFIG_IPV6_SIT)
3580 		case ARPHRD_SIT:
3581 			addrconf_sit_config(dev);
3582 			break;
3583 #endif
3584 #if IS_ENABLED(CONFIG_NET_IPGRE)
3585 		case ARPHRD_IPGRE:
3586 			addrconf_gre_config(dev);
3587 			break;
3588 #endif
3589 		case ARPHRD_LOOPBACK:
3590 			init_loopback(dev);
3591 			break;
3592 
3593 		default:
3594 			addrconf_dev_config(dev);
3595 			break;
3596 		}
3597 
3598 		if (!IS_ERR_OR_NULL(idev)) {
3599 			if (run_pending)
3600 				addrconf_dad_run(idev, false);
3601 
3602 			/* Device has an address by now */
3603 			rt6_sync_up(dev, RTNH_F_DEAD);
3604 
3605 			/*
3606 			 * If the MTU changed during the interface down,
3607 			 * when the interface up, the changed MTU must be
3608 			 * reflected in the idev as well as routers.
3609 			 */
3610 			if (idev->cnf.mtu6 != dev->mtu &&
3611 			    dev->mtu >= IPV6_MIN_MTU) {
3612 				rt6_mtu_change(dev, dev->mtu);
3613 				idev->cnf.mtu6 = dev->mtu;
3614 			}
3615 			idev->tstamp = jiffies;
3616 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3617 
3618 			/*
3619 			 * If the changed mtu during down is lower than
3620 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3621 			 */
3622 			if (dev->mtu < IPV6_MIN_MTU)
3623 				addrconf_ifdown(dev, dev != net->loopback_dev);
3624 		}
3625 		break;
3626 
3627 	case NETDEV_DOWN:
3628 	case NETDEV_UNREGISTER:
3629 		/*
3630 		 *	Remove all addresses from this interface.
3631 		 */
3632 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3633 		break;
3634 
3635 	case NETDEV_CHANGENAME:
3636 		if (idev) {
3637 			snmp6_unregister_dev(idev);
3638 			addrconf_sysctl_unregister(idev);
3639 			err = addrconf_sysctl_register(idev);
3640 			if (err)
3641 				return notifier_from_errno(err);
3642 			err = snmp6_register_dev(idev);
3643 			if (err) {
3644 				addrconf_sysctl_unregister(idev);
3645 				return notifier_from_errno(err);
3646 			}
3647 		}
3648 		break;
3649 
3650 	case NETDEV_PRE_TYPE_CHANGE:
3651 	case NETDEV_POST_TYPE_CHANGE:
3652 		if (idev)
3653 			addrconf_type_change(dev, event);
3654 		break;
3655 
3656 	case NETDEV_CHANGEUPPER:
3657 		info = ptr;
3658 
3659 		/* flush all routes if dev is linked to or unlinked from
3660 		 * an L3 master device (e.g., VRF)
3661 		 */
3662 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3663 			addrconf_ifdown(dev, 0);
3664 	}
3665 
3666 	return NOTIFY_OK;
3667 }
3668 
3669 /*
3670  *	addrconf module should be notified of a device going up
3671  */
3672 static struct notifier_block ipv6_dev_notf = {
3673 	.notifier_call = addrconf_notify,
3674 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3675 };
3676 
3677 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3678 {
3679 	struct inet6_dev *idev;
3680 	ASSERT_RTNL();
3681 
3682 	idev = __in6_dev_get(dev);
3683 
3684 	if (event == NETDEV_POST_TYPE_CHANGE)
3685 		ipv6_mc_remap(idev);
3686 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3687 		ipv6_mc_unmap(idev);
3688 }
3689 
3690 static bool addr_is_local(const struct in6_addr *addr)
3691 {
3692 	return ipv6_addr_type(addr) &
3693 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3694 }
3695 
3696 static int addrconf_ifdown(struct net_device *dev, int how)
3697 {
3698 	unsigned long event = how ? NETDEV_UNREGISTER : NETDEV_DOWN;
3699 	struct net *net = dev_net(dev);
3700 	struct inet6_dev *idev;
3701 	struct inet6_ifaddr *ifa, *tmp;
3702 	bool keep_addr = false;
3703 	int state, i;
3704 
3705 	ASSERT_RTNL();
3706 
3707 	rt6_disable_ip(dev, event);
3708 
3709 	idev = __in6_dev_get(dev);
3710 	if (!idev)
3711 		return -ENODEV;
3712 
3713 	/*
3714 	 * Step 1: remove reference to ipv6 device from parent device.
3715 	 *	   Do not dev_put!
3716 	 */
3717 	if (how) {
3718 		idev->dead = 1;
3719 
3720 		/* protected by rtnl_lock */
3721 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3722 
3723 		/* Step 1.5: remove snmp6 entry */
3724 		snmp6_unregister_dev(idev);
3725 
3726 	}
3727 
3728 	/* combine the user config with event to determine if permanent
3729 	 * addresses are to be removed from address hash table
3730 	 */
3731 	if (!how && !idev->cnf.disable_ipv6) {
3732 		/* aggregate the system setting and interface setting */
3733 		int _keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
3734 
3735 		if (!_keep_addr)
3736 			_keep_addr = idev->cnf.keep_addr_on_down;
3737 
3738 		keep_addr = (_keep_addr > 0);
3739 	}
3740 
3741 	/* Step 2: clear hash table */
3742 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3743 		struct hlist_head *h = &inet6_addr_lst[i];
3744 
3745 		spin_lock_bh(&addrconf_hash_lock);
3746 restart:
3747 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3748 			if (ifa->idev == idev) {
3749 				addrconf_del_dad_work(ifa);
3750 				/* combined flag + permanent flag decide if
3751 				 * address is retained on a down event
3752 				 */
3753 				if (!keep_addr ||
3754 				    !(ifa->flags & IFA_F_PERMANENT) ||
3755 				    addr_is_local(&ifa->addr)) {
3756 					hlist_del_init_rcu(&ifa->addr_lst);
3757 					goto restart;
3758 				}
3759 			}
3760 		}
3761 		spin_unlock_bh(&addrconf_hash_lock);
3762 	}
3763 
3764 	write_lock_bh(&idev->lock);
3765 
3766 	addrconf_del_rs_timer(idev);
3767 
3768 	/* Step 2: clear flags for stateless addrconf */
3769 	if (!how)
3770 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3771 
3772 	/* Step 3: clear tempaddr list */
3773 	while (!list_empty(&idev->tempaddr_list)) {
3774 		ifa = list_first_entry(&idev->tempaddr_list,
3775 				       struct inet6_ifaddr, tmp_list);
3776 		list_del(&ifa->tmp_list);
3777 		write_unlock_bh(&idev->lock);
3778 		spin_lock_bh(&ifa->lock);
3779 
3780 		if (ifa->ifpub) {
3781 			in6_ifa_put(ifa->ifpub);
3782 			ifa->ifpub = NULL;
3783 		}
3784 		spin_unlock_bh(&ifa->lock);
3785 		in6_ifa_put(ifa);
3786 		write_lock_bh(&idev->lock);
3787 	}
3788 
3789 	list_for_each_entry_safe(ifa, tmp, &idev->addr_list, if_list) {
3790 		struct fib6_info *rt = NULL;
3791 		bool keep;
3792 
3793 		addrconf_del_dad_work(ifa);
3794 
3795 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3796 			!addr_is_local(&ifa->addr);
3797 
3798 		write_unlock_bh(&idev->lock);
3799 		spin_lock_bh(&ifa->lock);
3800 
3801 		if (keep) {
3802 			/* set state to skip the notifier below */
3803 			state = INET6_IFADDR_STATE_DEAD;
3804 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3805 			if (!(ifa->flags & IFA_F_NODAD))
3806 				ifa->flags |= IFA_F_TENTATIVE;
3807 
3808 			rt = ifa->rt;
3809 			ifa->rt = NULL;
3810 		} else {
3811 			state = ifa->state;
3812 			ifa->state = INET6_IFADDR_STATE_DEAD;
3813 		}
3814 
3815 		spin_unlock_bh(&ifa->lock);
3816 
3817 		if (rt)
3818 			ip6_del_rt(net, rt);
3819 
3820 		if (state != INET6_IFADDR_STATE_DEAD) {
3821 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3822 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3823 		} else {
3824 			if (idev->cnf.forwarding)
3825 				addrconf_leave_anycast(ifa);
3826 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3827 		}
3828 
3829 		write_lock_bh(&idev->lock);
3830 		if (!keep) {
3831 			list_del_rcu(&ifa->if_list);
3832 			in6_ifa_put(ifa);
3833 		}
3834 	}
3835 
3836 	write_unlock_bh(&idev->lock);
3837 
3838 	/* Step 5: Discard anycast and multicast list */
3839 	if (how) {
3840 		ipv6_ac_destroy_dev(idev);
3841 		ipv6_mc_destroy_dev(idev);
3842 	} else {
3843 		ipv6_mc_down(idev);
3844 	}
3845 
3846 	idev->tstamp = jiffies;
3847 
3848 	/* Last: Shot the device (if unregistered) */
3849 	if (how) {
3850 		addrconf_sysctl_unregister(idev);
3851 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3852 		neigh_ifdown(&nd_tbl, dev);
3853 		in6_dev_put(idev);
3854 	}
3855 	return 0;
3856 }
3857 
3858 static void addrconf_rs_timer(struct timer_list *t)
3859 {
3860 	struct inet6_dev *idev = from_timer(idev, t, rs_timer);
3861 	struct net_device *dev = idev->dev;
3862 	struct in6_addr lladdr;
3863 
3864 	write_lock(&idev->lock);
3865 	if (idev->dead || !(idev->if_flags & IF_READY))
3866 		goto out;
3867 
3868 	if (!ipv6_accept_ra(idev))
3869 		goto out;
3870 
3871 	/* Announcement received after solicitation was sent */
3872 	if (idev->if_flags & IF_RA_RCVD)
3873 		goto out;
3874 
3875 	if (idev->rs_probes++ < idev->cnf.rtr_solicits || idev->cnf.rtr_solicits < 0) {
3876 		write_unlock(&idev->lock);
3877 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3878 			ndisc_send_rs(dev, &lladdr,
3879 				      &in6addr_linklocal_allrouters);
3880 		else
3881 			goto put;
3882 
3883 		write_lock(&idev->lock);
3884 		idev->rs_interval = rfc3315_s14_backoff_update(
3885 			idev->rs_interval, idev->cnf.rtr_solicit_max_interval);
3886 		/* The wait after the last probe can be shorter */
3887 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3888 					     idev->cnf.rtr_solicits) ?
3889 				      idev->cnf.rtr_solicit_delay :
3890 				      idev->rs_interval);
3891 	} else {
3892 		/*
3893 		 * Note: we do not support deprecated "all on-link"
3894 		 * assumption any longer.
3895 		 */
3896 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
3897 	}
3898 
3899 out:
3900 	write_unlock(&idev->lock);
3901 put:
3902 	in6_dev_put(idev);
3903 }
3904 
3905 /*
3906  *	Duplicate Address Detection
3907  */
3908 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
3909 {
3910 	unsigned long rand_num;
3911 	struct inet6_dev *idev = ifp->idev;
3912 	u64 nonce;
3913 
3914 	if (ifp->flags & IFA_F_OPTIMISTIC)
3915 		rand_num = 0;
3916 	else
3917 		rand_num = prandom_u32() % (idev->cnf.rtr_solicit_delay ? : 1);
3918 
3919 	nonce = 0;
3920 	if (idev->cnf.enhanced_dad ||
3921 	    dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad) {
3922 		do
3923 			get_random_bytes(&nonce, 6);
3924 		while (nonce == 0);
3925 	}
3926 	ifp->dad_nonce = nonce;
3927 	ifp->dad_probes = idev->cnf.dad_transmits;
3928 	addrconf_mod_dad_work(ifp, rand_num);
3929 }
3930 
3931 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
3932 {
3933 	struct inet6_dev *idev = ifp->idev;
3934 	struct net_device *dev = idev->dev;
3935 	bool bump_id, notify = false;
3936 	struct net *net;
3937 
3938 	addrconf_join_solict(dev, &ifp->addr);
3939 
3940 	prandom_seed((__force u32) ifp->addr.s6_addr32[3]);
3941 
3942 	read_lock_bh(&idev->lock);
3943 	spin_lock(&ifp->lock);
3944 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
3945 		goto out;
3946 
3947 	net = dev_net(dev);
3948 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
3949 	    (net->ipv6.devconf_all->accept_dad < 1 &&
3950 	     idev->cnf.accept_dad < 1) ||
3951 	    !(ifp->flags&IFA_F_TENTATIVE) ||
3952 	    ifp->flags & IFA_F_NODAD) {
3953 		bool send_na = false;
3954 
3955 		if (ifp->flags & IFA_F_TENTATIVE &&
3956 		    !(ifp->flags & IFA_F_OPTIMISTIC))
3957 			send_na = true;
3958 		bump_id = ifp->flags & IFA_F_TENTATIVE;
3959 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
3960 		spin_unlock(&ifp->lock);
3961 		read_unlock_bh(&idev->lock);
3962 
3963 		addrconf_dad_completed(ifp, bump_id, send_na);
3964 		return;
3965 	}
3966 
3967 	if (!(idev->if_flags & IF_READY)) {
3968 		spin_unlock(&ifp->lock);
3969 		read_unlock_bh(&idev->lock);
3970 		/*
3971 		 * If the device is not ready:
3972 		 * - keep it tentative if it is a permanent address.
3973 		 * - otherwise, kill it.
3974 		 */
3975 		in6_ifa_hold(ifp);
3976 		addrconf_dad_stop(ifp, 0);
3977 		return;
3978 	}
3979 
3980 	/*
3981 	 * Optimistic nodes can start receiving
3982 	 * Frames right away
3983 	 */
3984 	if (ifp->flags & IFA_F_OPTIMISTIC) {
3985 		ip6_ins_rt(net, ifp->rt);
3986 		if (ipv6_use_optimistic_addr(net, idev)) {
3987 			/* Because optimistic nodes can use this address,
3988 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
3989 			 */
3990 			notify = true;
3991 		}
3992 	}
3993 
3994 	addrconf_dad_kick(ifp);
3995 out:
3996 	spin_unlock(&ifp->lock);
3997 	read_unlock_bh(&idev->lock);
3998 	if (notify)
3999 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
4000 }
4001 
4002 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
4003 {
4004 	bool begin_dad = false;
4005 
4006 	spin_lock_bh(&ifp->lock);
4007 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
4008 		ifp->state = INET6_IFADDR_STATE_PREDAD;
4009 		begin_dad = true;
4010 	}
4011 	spin_unlock_bh(&ifp->lock);
4012 
4013 	if (begin_dad)
4014 		addrconf_mod_dad_work(ifp, 0);
4015 }
4016 
4017 static void addrconf_dad_work(struct work_struct *w)
4018 {
4019 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
4020 						struct inet6_ifaddr,
4021 						dad_work);
4022 	struct inet6_dev *idev = ifp->idev;
4023 	bool bump_id, disable_ipv6 = false;
4024 	struct in6_addr mcaddr;
4025 
4026 	enum {
4027 		DAD_PROCESS,
4028 		DAD_BEGIN,
4029 		DAD_ABORT,
4030 	} action = DAD_PROCESS;
4031 
4032 	rtnl_lock();
4033 
4034 	spin_lock_bh(&ifp->lock);
4035 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
4036 		action = DAD_BEGIN;
4037 		ifp->state = INET6_IFADDR_STATE_DAD;
4038 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
4039 		action = DAD_ABORT;
4040 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
4041 
4042 		if ((dev_net(idev->dev)->ipv6.devconf_all->accept_dad > 1 ||
4043 		     idev->cnf.accept_dad > 1) &&
4044 		    !idev->cnf.disable_ipv6 &&
4045 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
4046 			struct in6_addr addr;
4047 
4048 			addr.s6_addr32[0] = htonl(0xfe800000);
4049 			addr.s6_addr32[1] = 0;
4050 
4051 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
4052 			    ipv6_addr_equal(&ifp->addr, &addr)) {
4053 				/* DAD failed for link-local based on MAC */
4054 				idev->cnf.disable_ipv6 = 1;
4055 
4056 				pr_info("%s: IPv6 being disabled!\n",
4057 					ifp->idev->dev->name);
4058 				disable_ipv6 = true;
4059 			}
4060 		}
4061 	}
4062 	spin_unlock_bh(&ifp->lock);
4063 
4064 	if (action == DAD_BEGIN) {
4065 		addrconf_dad_begin(ifp);
4066 		goto out;
4067 	} else if (action == DAD_ABORT) {
4068 		in6_ifa_hold(ifp);
4069 		addrconf_dad_stop(ifp, 1);
4070 		if (disable_ipv6)
4071 			addrconf_ifdown(idev->dev, 0);
4072 		goto out;
4073 	}
4074 
4075 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
4076 		goto out;
4077 
4078 	write_lock_bh(&idev->lock);
4079 	if (idev->dead || !(idev->if_flags & IF_READY)) {
4080 		write_unlock_bh(&idev->lock);
4081 		goto out;
4082 	}
4083 
4084 	spin_lock(&ifp->lock);
4085 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
4086 		spin_unlock(&ifp->lock);
4087 		write_unlock_bh(&idev->lock);
4088 		goto out;
4089 	}
4090 
4091 	if (ifp->dad_probes == 0) {
4092 		bool send_na = false;
4093 
4094 		/*
4095 		 * DAD was successful
4096 		 */
4097 
4098 		if (ifp->flags & IFA_F_TENTATIVE &&
4099 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4100 			send_na = true;
4101 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4102 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4103 		spin_unlock(&ifp->lock);
4104 		write_unlock_bh(&idev->lock);
4105 
4106 		addrconf_dad_completed(ifp, bump_id, send_na);
4107 
4108 		goto out;
4109 	}
4110 
4111 	ifp->dad_probes--;
4112 	addrconf_mod_dad_work(ifp,
4113 			      NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME));
4114 	spin_unlock(&ifp->lock);
4115 	write_unlock_bh(&idev->lock);
4116 
4117 	/* send a neighbour solicitation for our addr */
4118 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4119 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4120 		      ifp->dad_nonce);
4121 out:
4122 	in6_ifa_put(ifp);
4123 	rtnl_unlock();
4124 }
4125 
4126 /* ifp->idev must be at least read locked */
4127 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4128 {
4129 	struct inet6_ifaddr *ifpiter;
4130 	struct inet6_dev *idev = ifp->idev;
4131 
4132 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4133 		if (ifpiter->scope > IFA_LINK)
4134 			break;
4135 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4136 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4137 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4138 		    IFA_F_PERMANENT)
4139 			return false;
4140 	}
4141 	return true;
4142 }
4143 
4144 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
4145 				   bool send_na)
4146 {
4147 	struct net_device *dev = ifp->idev->dev;
4148 	struct in6_addr lladdr;
4149 	bool send_rs, send_mld;
4150 
4151 	addrconf_del_dad_work(ifp);
4152 
4153 	/*
4154 	 *	Configure the address for reception. Now it is valid.
4155 	 */
4156 
4157 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4158 
4159 	/* If added prefix is link local and we are prepared to process
4160 	   router advertisements, start sending router solicitations.
4161 	 */
4162 
4163 	read_lock_bh(&ifp->idev->lock);
4164 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4165 	send_rs = send_mld &&
4166 		  ipv6_accept_ra(ifp->idev) &&
4167 		  ifp->idev->cnf.rtr_solicits != 0 &&
4168 		  (dev->flags&IFF_LOOPBACK) == 0;
4169 	read_unlock_bh(&ifp->idev->lock);
4170 
4171 	/* While dad is in progress mld report's source address is in6_addrany.
4172 	 * Resend with proper ll now.
4173 	 */
4174 	if (send_mld)
4175 		ipv6_mc_dad_complete(ifp->idev);
4176 
4177 	/* send unsolicited NA if enabled */
4178 	if (send_na &&
4179 	    (ifp->idev->cnf.ndisc_notify ||
4180 	     dev_net(dev)->ipv6.devconf_all->ndisc_notify)) {
4181 		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifp->addr,
4182 			      /*router=*/ !!ifp->idev->cnf.forwarding,
4183 			      /*solicited=*/ false, /*override=*/ true,
4184 			      /*inc_opt=*/ true);
4185 	}
4186 
4187 	if (send_rs) {
4188 		/*
4189 		 *	If a host as already performed a random delay
4190 		 *	[...] as part of DAD [...] there is no need
4191 		 *	to delay again before sending the first RS
4192 		 */
4193 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4194 			return;
4195 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4196 
4197 		write_lock_bh(&ifp->idev->lock);
4198 		spin_lock(&ifp->lock);
4199 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4200 			ifp->idev->cnf.rtr_solicit_interval);
4201 		ifp->idev->rs_probes = 1;
4202 		ifp->idev->if_flags |= IF_RS_SENT;
4203 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4204 		spin_unlock(&ifp->lock);
4205 		write_unlock_bh(&ifp->idev->lock);
4206 	}
4207 
4208 	if (bump_id)
4209 		rt_genid_bump_ipv6(dev_net(dev));
4210 
4211 	/* Make sure that a new temporary address will be created
4212 	 * before this temporary address becomes deprecated.
4213 	 */
4214 	if (ifp->flags & IFA_F_TEMPORARY)
4215 		addrconf_verify_rtnl();
4216 }
4217 
4218 static void addrconf_dad_run(struct inet6_dev *idev, bool restart)
4219 {
4220 	struct inet6_ifaddr *ifp;
4221 
4222 	read_lock_bh(&idev->lock);
4223 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4224 		spin_lock(&ifp->lock);
4225 		if ((ifp->flags & IFA_F_TENTATIVE &&
4226 		     ifp->state == INET6_IFADDR_STATE_DAD) || restart) {
4227 			if (restart)
4228 				ifp->state = INET6_IFADDR_STATE_PREDAD;
4229 			addrconf_dad_kick(ifp);
4230 		}
4231 		spin_unlock(&ifp->lock);
4232 	}
4233 	read_unlock_bh(&idev->lock);
4234 }
4235 
4236 #ifdef CONFIG_PROC_FS
4237 struct if6_iter_state {
4238 	struct seq_net_private p;
4239 	int bucket;
4240 	int offset;
4241 };
4242 
4243 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4244 {
4245 	struct if6_iter_state *state = seq->private;
4246 	struct net *net = seq_file_net(seq);
4247 	struct inet6_ifaddr *ifa = NULL;
4248 	int p = 0;
4249 
4250 	/* initial bucket if pos is 0 */
4251 	if (pos == 0) {
4252 		state->bucket = 0;
4253 		state->offset = 0;
4254 	}
4255 
4256 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4257 		hlist_for_each_entry_rcu(ifa, &inet6_addr_lst[state->bucket],
4258 					 addr_lst) {
4259 			if (!net_eq(dev_net(ifa->idev->dev), net))
4260 				continue;
4261 			/* sync with offset */
4262 			if (p < state->offset) {
4263 				p++;
4264 				continue;
4265 			}
4266 			return ifa;
4267 		}
4268 
4269 		/* prepare for next bucket */
4270 		state->offset = 0;
4271 		p = 0;
4272 	}
4273 	return NULL;
4274 }
4275 
4276 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4277 					 struct inet6_ifaddr *ifa)
4278 {
4279 	struct if6_iter_state *state = seq->private;
4280 	struct net *net = seq_file_net(seq);
4281 
4282 	hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4283 		if (!net_eq(dev_net(ifa->idev->dev), net))
4284 			continue;
4285 		state->offset++;
4286 		return ifa;
4287 	}
4288 
4289 	state->offset = 0;
4290 	while (++state->bucket < IN6_ADDR_HSIZE) {
4291 		hlist_for_each_entry_rcu(ifa,
4292 				     &inet6_addr_lst[state->bucket], addr_lst) {
4293 			if (!net_eq(dev_net(ifa->idev->dev), net))
4294 				continue;
4295 			return ifa;
4296 		}
4297 	}
4298 
4299 	return NULL;
4300 }
4301 
4302 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4303 	__acquires(rcu)
4304 {
4305 	rcu_read_lock();
4306 	return if6_get_first(seq, *pos);
4307 }
4308 
4309 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4310 {
4311 	struct inet6_ifaddr *ifa;
4312 
4313 	ifa = if6_get_next(seq, v);
4314 	++*pos;
4315 	return ifa;
4316 }
4317 
4318 static void if6_seq_stop(struct seq_file *seq, void *v)
4319 	__releases(rcu)
4320 {
4321 	rcu_read_unlock();
4322 }
4323 
4324 static int if6_seq_show(struct seq_file *seq, void *v)
4325 {
4326 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4327 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4328 		   &ifp->addr,
4329 		   ifp->idev->dev->ifindex,
4330 		   ifp->prefix_len,
4331 		   ifp->scope,
4332 		   (u8) ifp->flags,
4333 		   ifp->idev->dev->name);
4334 	return 0;
4335 }
4336 
4337 static const struct seq_operations if6_seq_ops = {
4338 	.start	= if6_seq_start,
4339 	.next	= if6_seq_next,
4340 	.show	= if6_seq_show,
4341 	.stop	= if6_seq_stop,
4342 };
4343 
4344 static int __net_init if6_proc_net_init(struct net *net)
4345 {
4346 	if (!proc_create_net("if_inet6", 0444, net->proc_net, &if6_seq_ops,
4347 			sizeof(struct if6_iter_state)))
4348 		return -ENOMEM;
4349 	return 0;
4350 }
4351 
4352 static void __net_exit if6_proc_net_exit(struct net *net)
4353 {
4354 	remove_proc_entry("if_inet6", net->proc_net);
4355 }
4356 
4357 static struct pernet_operations if6_proc_net_ops = {
4358 	.init = if6_proc_net_init,
4359 	.exit = if6_proc_net_exit,
4360 };
4361 
4362 int __init if6_proc_init(void)
4363 {
4364 	return register_pernet_subsys(&if6_proc_net_ops);
4365 }
4366 
4367 void if6_proc_exit(void)
4368 {
4369 	unregister_pernet_subsys(&if6_proc_net_ops);
4370 }
4371 #endif	/* CONFIG_PROC_FS */
4372 
4373 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4374 /* Check if address is a home address configured on any interface. */
4375 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4376 {
4377 	unsigned int hash = inet6_addr_hash(net, addr);
4378 	struct inet6_ifaddr *ifp = NULL;
4379 	int ret = 0;
4380 
4381 	rcu_read_lock();
4382 	hlist_for_each_entry_rcu(ifp, &inet6_addr_lst[hash], addr_lst) {
4383 		if (!net_eq(dev_net(ifp->idev->dev), net))
4384 			continue;
4385 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4386 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4387 			ret = 1;
4388 			break;
4389 		}
4390 	}
4391 	rcu_read_unlock();
4392 	return ret;
4393 }
4394 #endif
4395 
4396 /*
4397  *	Periodic address status verification
4398  */
4399 
4400 static void addrconf_verify_rtnl(void)
4401 {
4402 	unsigned long now, next, next_sec, next_sched;
4403 	struct inet6_ifaddr *ifp;
4404 	int i;
4405 
4406 	ASSERT_RTNL();
4407 
4408 	rcu_read_lock_bh();
4409 	now = jiffies;
4410 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4411 
4412 	cancel_delayed_work(&addr_chk_work);
4413 
4414 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4415 restart:
4416 		hlist_for_each_entry_rcu_bh(ifp, &inet6_addr_lst[i], addr_lst) {
4417 			unsigned long age;
4418 
4419 			/* When setting preferred_lft to a value not zero or
4420 			 * infinity, while valid_lft is infinity
4421 			 * IFA_F_PERMANENT has a non-infinity life time.
4422 			 */
4423 			if ((ifp->flags & IFA_F_PERMANENT) &&
4424 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4425 				continue;
4426 
4427 			spin_lock(&ifp->lock);
4428 			/* We try to batch several events at once. */
4429 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4430 
4431 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4432 			    age >= ifp->valid_lft) {
4433 				spin_unlock(&ifp->lock);
4434 				in6_ifa_hold(ifp);
4435 				ipv6_del_addr(ifp);
4436 				goto restart;
4437 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4438 				spin_unlock(&ifp->lock);
4439 				continue;
4440 			} else if (age >= ifp->prefered_lft) {
4441 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4442 				int deprecate = 0;
4443 
4444 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4445 					deprecate = 1;
4446 					ifp->flags |= IFA_F_DEPRECATED;
4447 				}
4448 
4449 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4450 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4451 					next = ifp->tstamp + ifp->valid_lft * HZ;
4452 
4453 				spin_unlock(&ifp->lock);
4454 
4455 				if (deprecate) {
4456 					in6_ifa_hold(ifp);
4457 
4458 					ipv6_ifa_notify(0, ifp);
4459 					in6_ifa_put(ifp);
4460 					goto restart;
4461 				}
4462 			} else if ((ifp->flags&IFA_F_TEMPORARY) &&
4463 				   !(ifp->flags&IFA_F_TENTATIVE)) {
4464 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
4465 					ifp->idev->cnf.dad_transmits *
4466 					NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME) / HZ;
4467 
4468 				if (age >= ifp->prefered_lft - regen_advance) {
4469 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4470 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4471 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4472 					if (!ifp->regen_count && ifpub) {
4473 						ifp->regen_count++;
4474 						in6_ifa_hold(ifp);
4475 						in6_ifa_hold(ifpub);
4476 						spin_unlock(&ifp->lock);
4477 
4478 						spin_lock(&ifpub->lock);
4479 						ifpub->regen_count = 0;
4480 						spin_unlock(&ifpub->lock);
4481 						rcu_read_unlock_bh();
4482 						ipv6_create_tempaddr(ifpub, ifp, true);
4483 						in6_ifa_put(ifpub);
4484 						in6_ifa_put(ifp);
4485 						rcu_read_lock_bh();
4486 						goto restart;
4487 					}
4488 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4489 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4490 				spin_unlock(&ifp->lock);
4491 			} else {
4492 				/* ifp->prefered_lft <= ifp->valid_lft */
4493 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4494 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4495 				spin_unlock(&ifp->lock);
4496 			}
4497 		}
4498 	}
4499 
4500 	next_sec = round_jiffies_up(next);
4501 	next_sched = next;
4502 
4503 	/* If rounded timeout is accurate enough, accept it. */
4504 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4505 		next_sched = next_sec;
4506 
4507 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4508 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4509 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4510 
4511 	pr_debug("now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4512 		 now, next, next_sec, next_sched);
4513 	mod_delayed_work(addrconf_wq, &addr_chk_work, next_sched - now);
4514 	rcu_read_unlock_bh();
4515 }
4516 
4517 static void addrconf_verify_work(struct work_struct *w)
4518 {
4519 	rtnl_lock();
4520 	addrconf_verify_rtnl();
4521 	rtnl_unlock();
4522 }
4523 
4524 static void addrconf_verify(void)
4525 {
4526 	mod_delayed_work(addrconf_wq, &addr_chk_work, 0);
4527 }
4528 
4529 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4530 				     struct in6_addr **peer_pfx)
4531 {
4532 	struct in6_addr *pfx = NULL;
4533 
4534 	*peer_pfx = NULL;
4535 
4536 	if (addr)
4537 		pfx = nla_data(addr);
4538 
4539 	if (local) {
4540 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4541 			*peer_pfx = pfx;
4542 		pfx = nla_data(local);
4543 	}
4544 
4545 	return pfx;
4546 }
4547 
4548 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4549 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4550 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4551 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4552 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4553 	[IFA_RT_PRIORITY]	= { .len = sizeof(u32) },
4554 	[IFA_TARGET_NETNSID]	= { .type = NLA_S32 },
4555 };
4556 
4557 static int
4558 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4559 		  struct netlink_ext_ack *extack)
4560 {
4561 	struct net *net = sock_net(skb->sk);
4562 	struct ifaddrmsg *ifm;
4563 	struct nlattr *tb[IFA_MAX+1];
4564 	struct in6_addr *pfx, *peer_pfx;
4565 	u32 ifa_flags;
4566 	int err;
4567 
4568 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4569 			  extack);
4570 	if (err < 0)
4571 		return err;
4572 
4573 	ifm = nlmsg_data(nlh);
4574 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4575 	if (!pfx)
4576 		return -EINVAL;
4577 
4578 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4579 
4580 	/* We ignore other flags so far. */
4581 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4582 
4583 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4584 			      ifm->ifa_prefixlen);
4585 }
4586 
4587 static int modify_prefix_route(struct inet6_ifaddr *ifp,
4588 			       unsigned long expires, u32 flags)
4589 {
4590 	struct fib6_info *f6i;
4591 	u32 prio;
4592 
4593 	f6i = addrconf_get_prefix_route(&ifp->addr, ifp->prefix_len,
4594 					ifp->idev->dev, 0, RTF_DEFAULT, true);
4595 	if (!f6i)
4596 		return -ENOENT;
4597 
4598 	prio = ifp->rt_priority ? : IP6_RT_PRIO_ADDRCONF;
4599 	if (f6i->fib6_metric != prio) {
4600 		/* delete old one */
4601 		ip6_del_rt(dev_net(ifp->idev->dev), f6i);
4602 
4603 		/* add new one */
4604 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4605 				      ifp->rt_priority, ifp->idev->dev,
4606 				      expires, flags, GFP_KERNEL);
4607 	} else {
4608 		if (!expires)
4609 			fib6_clean_expires(f6i);
4610 		else
4611 			fib6_set_expires(f6i, expires);
4612 
4613 		fib6_info_release(f6i);
4614 	}
4615 
4616 	return 0;
4617 }
4618 
4619 static int inet6_addr_modify(struct inet6_ifaddr *ifp, struct ifa6_config *cfg)
4620 {
4621 	u32 flags;
4622 	clock_t expires;
4623 	unsigned long timeout;
4624 	bool was_managetempaddr;
4625 	bool had_prefixroute;
4626 
4627 	ASSERT_RTNL();
4628 
4629 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
4630 		return -EINVAL;
4631 
4632 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR &&
4633 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4634 		return -EINVAL;
4635 
4636 	if (!(ifp->flags & IFA_F_TENTATIVE) || ifp->flags & IFA_F_DADFAILED)
4637 		cfg->ifa_flags &= ~IFA_F_OPTIMISTIC;
4638 
4639 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
4640 	if (addrconf_finite_timeout(timeout)) {
4641 		expires = jiffies_to_clock_t(timeout * HZ);
4642 		cfg->valid_lft = timeout;
4643 		flags = RTF_EXPIRES;
4644 	} else {
4645 		expires = 0;
4646 		flags = 0;
4647 		cfg->ifa_flags |= IFA_F_PERMANENT;
4648 	}
4649 
4650 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
4651 	if (addrconf_finite_timeout(timeout)) {
4652 		if (timeout == 0)
4653 			cfg->ifa_flags |= IFA_F_DEPRECATED;
4654 		cfg->preferred_lft = timeout;
4655 	}
4656 
4657 	spin_lock_bh(&ifp->lock);
4658 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4659 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4660 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4661 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4662 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4663 			IFA_F_NOPREFIXROUTE);
4664 	ifp->flags |= cfg->ifa_flags;
4665 	ifp->tstamp = jiffies;
4666 	ifp->valid_lft = cfg->valid_lft;
4667 	ifp->prefered_lft = cfg->preferred_lft;
4668 
4669 	if (cfg->rt_priority && cfg->rt_priority != ifp->rt_priority)
4670 		ifp->rt_priority = cfg->rt_priority;
4671 
4672 	spin_unlock_bh(&ifp->lock);
4673 	if (!(ifp->flags&IFA_F_TENTATIVE))
4674 		ipv6_ifa_notify(0, ifp);
4675 
4676 	if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
4677 		int rc = -ENOENT;
4678 
4679 		if (had_prefixroute)
4680 			rc = modify_prefix_route(ifp, expires, flags);
4681 
4682 		/* prefix route could have been deleted; if so restore it */
4683 		if (rc == -ENOENT) {
4684 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4685 					      ifp->rt_priority, ifp->idev->dev,
4686 					      expires, flags, GFP_KERNEL);
4687 		}
4688 	} else if (had_prefixroute) {
4689 		enum cleanup_prefix_rt_t action;
4690 		unsigned long rt_expires;
4691 
4692 		write_lock_bh(&ifp->idev->lock);
4693 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4694 		write_unlock_bh(&ifp->idev->lock);
4695 
4696 		if (action != CLEANUP_PREFIX_RT_NOP) {
4697 			cleanup_prefix_route(ifp, rt_expires,
4698 				action == CLEANUP_PREFIX_RT_DEL);
4699 		}
4700 	}
4701 
4702 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4703 		if (was_managetempaddr &&
4704 		    !(ifp->flags & IFA_F_MANAGETEMPADDR)) {
4705 			cfg->valid_lft = 0;
4706 			cfg->preferred_lft = 0;
4707 		}
4708 		manage_tempaddrs(ifp->idev, ifp, cfg->valid_lft,
4709 				 cfg->preferred_lft, !was_managetempaddr,
4710 				 jiffies);
4711 	}
4712 
4713 	addrconf_verify_rtnl();
4714 
4715 	return 0;
4716 }
4717 
4718 static int
4719 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4720 		  struct netlink_ext_ack *extack)
4721 {
4722 	struct net *net = sock_net(skb->sk);
4723 	struct ifaddrmsg *ifm;
4724 	struct nlattr *tb[IFA_MAX+1];
4725 	struct in6_addr *peer_pfx;
4726 	struct inet6_ifaddr *ifa;
4727 	struct net_device *dev;
4728 	struct inet6_dev *idev;
4729 	struct ifa6_config cfg;
4730 	int err;
4731 
4732 	err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_ipv6_policy,
4733 			  extack);
4734 	if (err < 0)
4735 		return err;
4736 
4737 	memset(&cfg, 0, sizeof(cfg));
4738 
4739 	ifm = nlmsg_data(nlh);
4740 	cfg.pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4741 	if (!cfg.pfx)
4742 		return -EINVAL;
4743 
4744 	cfg.peer_pfx = peer_pfx;
4745 	cfg.plen = ifm->ifa_prefixlen;
4746 	if (tb[IFA_RT_PRIORITY])
4747 		cfg.rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
4748 
4749 	cfg.valid_lft = INFINITY_LIFE_TIME;
4750 	cfg.preferred_lft = INFINITY_LIFE_TIME;
4751 
4752 	if (tb[IFA_CACHEINFO]) {
4753 		struct ifa_cacheinfo *ci;
4754 
4755 		ci = nla_data(tb[IFA_CACHEINFO]);
4756 		cfg.valid_lft = ci->ifa_valid;
4757 		cfg.preferred_lft = ci->ifa_prefered;
4758 	}
4759 
4760 	dev =  __dev_get_by_index(net, ifm->ifa_index);
4761 	if (!dev)
4762 		return -ENODEV;
4763 
4764 	if (tb[IFA_FLAGS])
4765 		cfg.ifa_flags = nla_get_u32(tb[IFA_FLAGS]);
4766 	else
4767 		cfg.ifa_flags = ifm->ifa_flags;
4768 
4769 	/* We ignore other flags so far. */
4770 	cfg.ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS |
4771 			 IFA_F_MANAGETEMPADDR | IFA_F_NOPREFIXROUTE |
4772 			 IFA_F_MCAUTOJOIN | IFA_F_OPTIMISTIC;
4773 
4774 	idev = ipv6_find_idev(dev);
4775 	if (!idev)
4776 		return -ENOBUFS;
4777 
4778 	if (!ipv6_allow_optimistic_dad(net, idev))
4779 		cfg.ifa_flags &= ~IFA_F_OPTIMISTIC;
4780 
4781 	if (cfg.ifa_flags & IFA_F_NODAD &&
4782 	    cfg.ifa_flags & IFA_F_OPTIMISTIC) {
4783 		NL_SET_ERR_MSG(extack, "IFA_F_NODAD and IFA_F_OPTIMISTIC are mutually exclusive");
4784 		return -EINVAL;
4785 	}
4786 
4787 	ifa = ipv6_get_ifaddr(net, cfg.pfx, dev, 1);
4788 	if (!ifa) {
4789 		/*
4790 		 * It would be best to check for !NLM_F_CREATE here but
4791 		 * userspace already relies on not having to provide this.
4792 		 */
4793 		return inet6_addr_add(net, ifm->ifa_index, &cfg, extack);
4794 	}
4795 
4796 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
4797 	    !(nlh->nlmsg_flags & NLM_F_REPLACE))
4798 		err = -EEXIST;
4799 	else
4800 		err = inet6_addr_modify(ifa, &cfg);
4801 
4802 	in6_ifa_put(ifa);
4803 
4804 	return err;
4805 }
4806 
4807 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
4808 			  u8 scope, int ifindex)
4809 {
4810 	struct ifaddrmsg *ifm;
4811 
4812 	ifm = nlmsg_data(nlh);
4813 	ifm->ifa_family = AF_INET6;
4814 	ifm->ifa_prefixlen = prefixlen;
4815 	ifm->ifa_flags = flags;
4816 	ifm->ifa_scope = scope;
4817 	ifm->ifa_index = ifindex;
4818 }
4819 
4820 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
4821 			 unsigned long tstamp, u32 preferred, u32 valid)
4822 {
4823 	struct ifa_cacheinfo ci;
4824 
4825 	ci.cstamp = cstamp_delta(cstamp);
4826 	ci.tstamp = cstamp_delta(tstamp);
4827 	ci.ifa_prefered = preferred;
4828 	ci.ifa_valid = valid;
4829 
4830 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
4831 }
4832 
4833 static inline int rt_scope(int ifa_scope)
4834 {
4835 	if (ifa_scope & IFA_HOST)
4836 		return RT_SCOPE_HOST;
4837 	else if (ifa_scope & IFA_LINK)
4838 		return RT_SCOPE_LINK;
4839 	else if (ifa_scope & IFA_SITE)
4840 		return RT_SCOPE_SITE;
4841 	else
4842 		return RT_SCOPE_UNIVERSE;
4843 }
4844 
4845 static inline int inet6_ifaddr_msgsize(void)
4846 {
4847 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
4848 	       + nla_total_size(16) /* IFA_LOCAL */
4849 	       + nla_total_size(16) /* IFA_ADDRESS */
4850 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
4851 	       + nla_total_size(4)  /* IFA_FLAGS */
4852 	       + nla_total_size(4)  /* IFA_RT_PRIORITY */;
4853 }
4854 
4855 enum addr_type_t {
4856 	UNICAST_ADDR,
4857 	MULTICAST_ADDR,
4858 	ANYCAST_ADDR,
4859 };
4860 
4861 struct inet6_fill_args {
4862 	u32 portid;
4863 	u32 seq;
4864 	int event;
4865 	unsigned int flags;
4866 	int netnsid;
4867 	int ifindex;
4868 	enum addr_type_t type;
4869 };
4870 
4871 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
4872 			     struct inet6_fill_args *args)
4873 {
4874 	struct nlmsghdr  *nlh;
4875 	u32 preferred, valid;
4876 
4877 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
4878 			sizeof(struct ifaddrmsg), args->flags);
4879 	if (!nlh)
4880 		return -EMSGSIZE;
4881 
4882 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
4883 		      ifa->idev->dev->ifindex);
4884 
4885 	if (args->netnsid >= 0 &&
4886 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
4887 		goto error;
4888 
4889 	if (!((ifa->flags&IFA_F_PERMANENT) &&
4890 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
4891 		preferred = ifa->prefered_lft;
4892 		valid = ifa->valid_lft;
4893 		if (preferred != INFINITY_LIFE_TIME) {
4894 			long tval = (jiffies - ifa->tstamp)/HZ;
4895 			if (preferred > tval)
4896 				preferred -= tval;
4897 			else
4898 				preferred = 0;
4899 			if (valid != INFINITY_LIFE_TIME) {
4900 				if (valid > tval)
4901 					valid -= tval;
4902 				else
4903 					valid = 0;
4904 			}
4905 		}
4906 	} else {
4907 		preferred = INFINITY_LIFE_TIME;
4908 		valid = INFINITY_LIFE_TIME;
4909 	}
4910 
4911 	if (!ipv6_addr_any(&ifa->peer_addr)) {
4912 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
4913 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
4914 			goto error;
4915 	} else
4916 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
4917 			goto error;
4918 
4919 	if (ifa->rt_priority &&
4920 	    nla_put_u32(skb, IFA_RT_PRIORITY, ifa->rt_priority))
4921 		goto error;
4922 
4923 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
4924 		goto error;
4925 
4926 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
4927 		goto error;
4928 
4929 	nlmsg_end(skb, nlh);
4930 	return 0;
4931 
4932 error:
4933 	nlmsg_cancel(skb, nlh);
4934 	return -EMSGSIZE;
4935 }
4936 
4937 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
4938 			       struct inet6_fill_args *args)
4939 {
4940 	struct nlmsghdr  *nlh;
4941 	u8 scope = RT_SCOPE_UNIVERSE;
4942 	int ifindex = ifmca->idev->dev->ifindex;
4943 
4944 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
4945 		scope = RT_SCOPE_SITE;
4946 
4947 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
4948 			sizeof(struct ifaddrmsg), args->flags);
4949 	if (!nlh)
4950 		return -EMSGSIZE;
4951 
4952 	if (args->netnsid >= 0 &&
4953 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
4954 		return -EMSGSIZE;
4955 
4956 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4957 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
4958 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
4959 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4960 		nlmsg_cancel(skb, nlh);
4961 		return -EMSGSIZE;
4962 	}
4963 
4964 	nlmsg_end(skb, nlh);
4965 	return 0;
4966 }
4967 
4968 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
4969 			       struct inet6_fill_args *args)
4970 {
4971 	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
4972 	int ifindex = dev ? dev->ifindex : 1;
4973 	struct nlmsghdr  *nlh;
4974 	u8 scope = RT_SCOPE_UNIVERSE;
4975 
4976 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
4977 		scope = RT_SCOPE_SITE;
4978 
4979 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
4980 			sizeof(struct ifaddrmsg), args->flags);
4981 	if (!nlh)
4982 		return -EMSGSIZE;
4983 
4984 	if (args->netnsid >= 0 &&
4985 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
4986 		return -EMSGSIZE;
4987 
4988 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
4989 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
4990 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
4991 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
4992 		nlmsg_cancel(skb, nlh);
4993 		return -EMSGSIZE;
4994 	}
4995 
4996 	nlmsg_end(skb, nlh);
4997 	return 0;
4998 }
4999 
5000 /* called with rcu_read_lock() */
5001 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
5002 			  struct netlink_callback *cb, int s_ip_idx,
5003 			  struct inet6_fill_args *fillargs)
5004 {
5005 	struct ifmcaddr6 *ifmca;
5006 	struct ifacaddr6 *ifaca;
5007 	int ip_idx = 0;
5008 	int err = 1;
5009 
5010 	read_lock_bh(&idev->lock);
5011 	switch (fillargs->type) {
5012 	case UNICAST_ADDR: {
5013 		struct inet6_ifaddr *ifa;
5014 		fillargs->event = RTM_NEWADDR;
5015 
5016 		/* unicast address incl. temp addr */
5017 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
5018 			if (ip_idx < s_ip_idx)
5019 				goto next;
5020 			err = inet6_fill_ifaddr(skb, ifa, fillargs);
5021 			if (err < 0)
5022 				break;
5023 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
5024 next:
5025 			ip_idx++;
5026 		}
5027 		break;
5028 	}
5029 	case MULTICAST_ADDR:
5030 		fillargs->event = RTM_GETMULTICAST;
5031 
5032 		/* multicast address */
5033 		for (ifmca = idev->mc_list; ifmca;
5034 		     ifmca = ifmca->next, ip_idx++) {
5035 			if (ip_idx < s_ip_idx)
5036 				continue;
5037 			err = inet6_fill_ifmcaddr(skb, ifmca, fillargs);
5038 			if (err < 0)
5039 				break;
5040 		}
5041 		break;
5042 	case ANYCAST_ADDR:
5043 		fillargs->event = RTM_GETANYCAST;
5044 		/* anycast address */
5045 		for (ifaca = idev->ac_list; ifaca;
5046 		     ifaca = ifaca->aca_next, ip_idx++) {
5047 			if (ip_idx < s_ip_idx)
5048 				continue;
5049 			err = inet6_fill_ifacaddr(skb, ifaca, fillargs);
5050 			if (err < 0)
5051 				break;
5052 		}
5053 		break;
5054 	default:
5055 		break;
5056 	}
5057 	read_unlock_bh(&idev->lock);
5058 	cb->args[2] = ip_idx;
5059 	return err;
5060 }
5061 
5062 static int inet6_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
5063 				       struct inet6_fill_args *fillargs,
5064 				       struct net **tgt_net, struct sock *sk,
5065 				       struct netlink_callback *cb)
5066 {
5067 	struct netlink_ext_ack *extack = cb->extack;
5068 	struct nlattr *tb[IFA_MAX+1];
5069 	struct ifaddrmsg *ifm;
5070 	int err, i;
5071 
5072 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5073 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for address dump request");
5074 		return -EINVAL;
5075 	}
5076 
5077 	ifm = nlmsg_data(nlh);
5078 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5079 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address dump request");
5080 		return -EINVAL;
5081 	}
5082 
5083 	fillargs->ifindex = ifm->ifa_index;
5084 	if (fillargs->ifindex) {
5085 		cb->answer_flags |= NLM_F_DUMP_FILTERED;
5086 		fillargs->flags |= NLM_F_DUMP_FILTERED;
5087 	}
5088 
5089 	err = nlmsg_parse_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5090 				 ifa_ipv6_policy, extack);
5091 	if (err < 0)
5092 		return err;
5093 
5094 	for (i = 0; i <= IFA_MAX; ++i) {
5095 		if (!tb[i])
5096 			continue;
5097 
5098 		if (i == IFA_TARGET_NETNSID) {
5099 			struct net *net;
5100 
5101 			fillargs->netnsid = nla_get_s32(tb[i]);
5102 			net = rtnl_get_net_ns_capable(sk, fillargs->netnsid);
5103 			if (IS_ERR(net)) {
5104 				fillargs->netnsid = -1;
5105 				NL_SET_ERR_MSG_MOD(extack, "Invalid target network namespace id");
5106 				return PTR_ERR(net);
5107 			}
5108 			*tgt_net = net;
5109 		} else {
5110 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request");
5111 			return -EINVAL;
5112 		}
5113 	}
5114 
5115 	return 0;
5116 }
5117 
5118 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
5119 			   enum addr_type_t type)
5120 {
5121 	const struct nlmsghdr *nlh = cb->nlh;
5122 	struct inet6_fill_args fillargs = {
5123 		.portid = NETLINK_CB(cb->skb).portid,
5124 		.seq = cb->nlh->nlmsg_seq,
5125 		.flags = NLM_F_MULTI,
5126 		.netnsid = -1,
5127 		.type = type,
5128 	};
5129 	struct net *net = sock_net(skb->sk);
5130 	struct net *tgt_net = net;
5131 	int idx, s_idx, s_ip_idx;
5132 	int h, s_h;
5133 	struct net_device *dev;
5134 	struct inet6_dev *idev;
5135 	struct hlist_head *head;
5136 	int err = 0;
5137 
5138 	s_h = cb->args[0];
5139 	s_idx = idx = cb->args[1];
5140 	s_ip_idx = cb->args[2];
5141 
5142 	if (cb->strict_check) {
5143 		err = inet6_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
5144 						  skb->sk, cb);
5145 		if (err < 0)
5146 			goto put_tgt_net;
5147 
5148 		err = 0;
5149 		if (fillargs.ifindex) {
5150 			dev = __dev_get_by_index(tgt_net, fillargs.ifindex);
5151 			if (!dev) {
5152 				err = -ENODEV;
5153 				goto put_tgt_net;
5154 			}
5155 			idev = __in6_dev_get(dev);
5156 			if (idev) {
5157 				err = in6_dump_addrs(idev, skb, cb, s_ip_idx,
5158 						     &fillargs);
5159 				if (err > 0)
5160 					err = 0;
5161 			}
5162 			goto put_tgt_net;
5163 		}
5164 	}
5165 
5166 	rcu_read_lock();
5167 	cb->seq = atomic_read(&tgt_net->ipv6.dev_addr_genid) ^ tgt_net->dev_base_seq;
5168 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5169 		idx = 0;
5170 		head = &tgt_net->dev_index_head[h];
5171 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5172 			if (idx < s_idx)
5173 				goto cont;
5174 			if (h > s_h || idx > s_idx)
5175 				s_ip_idx = 0;
5176 			idev = __in6_dev_get(dev);
5177 			if (!idev)
5178 				goto cont;
5179 
5180 			if (in6_dump_addrs(idev, skb, cb, s_ip_idx,
5181 					   &fillargs) < 0)
5182 				goto done;
5183 cont:
5184 			idx++;
5185 		}
5186 	}
5187 done:
5188 	rcu_read_unlock();
5189 	cb->args[0] = h;
5190 	cb->args[1] = idx;
5191 put_tgt_net:
5192 	if (fillargs.netnsid >= 0)
5193 		put_net(tgt_net);
5194 
5195 	return skb->len ? : err;
5196 }
5197 
5198 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
5199 {
5200 	enum addr_type_t type = UNICAST_ADDR;
5201 
5202 	return inet6_dump_addr(skb, cb, type);
5203 }
5204 
5205 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
5206 {
5207 	enum addr_type_t type = MULTICAST_ADDR;
5208 
5209 	return inet6_dump_addr(skb, cb, type);
5210 }
5211 
5212 
5213 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
5214 {
5215 	enum addr_type_t type = ANYCAST_ADDR;
5216 
5217 	return inet6_dump_addr(skb, cb, type);
5218 }
5219 
5220 static int inet6_rtm_valid_getaddr_req(struct sk_buff *skb,
5221 				       const struct nlmsghdr *nlh,
5222 				       struct nlattr **tb,
5223 				       struct netlink_ext_ack *extack)
5224 {
5225 	struct ifaddrmsg *ifm;
5226 	int i, err;
5227 
5228 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5229 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for get address request");
5230 		return -EINVAL;
5231 	}
5232 
5233 	ifm = nlmsg_data(nlh);
5234 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5235 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get address request");
5236 		return -EINVAL;
5237 	}
5238 
5239 	if (!netlink_strict_get_check(skb))
5240 		return nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX,
5241 				   ifa_ipv6_policy, extack);
5242 
5243 	err = nlmsg_parse_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5244 				 ifa_ipv6_policy, extack);
5245 	if (err)
5246 		return err;
5247 
5248 	for (i = 0; i <= IFA_MAX; i++) {
5249 		if (!tb[i])
5250 			continue;
5251 
5252 		switch (i) {
5253 		case IFA_TARGET_NETNSID:
5254 		case IFA_ADDRESS:
5255 		case IFA_LOCAL:
5256 			break;
5257 		default:
5258 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get address request");
5259 			return -EINVAL;
5260 		}
5261 	}
5262 
5263 	return 0;
5264 }
5265 
5266 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5267 			     struct netlink_ext_ack *extack)
5268 {
5269 	struct net *net = sock_net(in_skb->sk);
5270 	struct inet6_fill_args fillargs = {
5271 		.portid = NETLINK_CB(in_skb).portid,
5272 		.seq = nlh->nlmsg_seq,
5273 		.event = RTM_NEWADDR,
5274 		.flags = 0,
5275 		.netnsid = -1,
5276 	};
5277 	struct net *tgt_net = net;
5278 	struct ifaddrmsg *ifm;
5279 	struct nlattr *tb[IFA_MAX+1];
5280 	struct in6_addr *addr = NULL, *peer;
5281 	struct net_device *dev = NULL;
5282 	struct inet6_ifaddr *ifa;
5283 	struct sk_buff *skb;
5284 	int err;
5285 
5286 	err = inet6_rtm_valid_getaddr_req(in_skb, nlh, tb, extack);
5287 	if (err < 0)
5288 		return err;
5289 
5290 	if (tb[IFA_TARGET_NETNSID]) {
5291 		fillargs.netnsid = nla_get_s32(tb[IFA_TARGET_NETNSID]);
5292 
5293 		tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(in_skb).sk,
5294 						  fillargs.netnsid);
5295 		if (IS_ERR(tgt_net))
5296 			return PTR_ERR(tgt_net);
5297 	}
5298 
5299 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
5300 	if (!addr)
5301 		return -EINVAL;
5302 
5303 	ifm = nlmsg_data(nlh);
5304 	if (ifm->ifa_index)
5305 		dev = dev_get_by_index(tgt_net, ifm->ifa_index);
5306 
5307 	ifa = ipv6_get_ifaddr(tgt_net, addr, dev, 1);
5308 	if (!ifa) {
5309 		err = -EADDRNOTAVAIL;
5310 		goto errout;
5311 	}
5312 
5313 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
5314 	if (!skb) {
5315 		err = -ENOBUFS;
5316 		goto errout_ifa;
5317 	}
5318 
5319 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5320 	if (err < 0) {
5321 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5322 		WARN_ON(err == -EMSGSIZE);
5323 		kfree_skb(skb);
5324 		goto errout_ifa;
5325 	}
5326 	err = rtnl_unicast(skb, tgt_net, NETLINK_CB(in_skb).portid);
5327 errout_ifa:
5328 	in6_ifa_put(ifa);
5329 errout:
5330 	if (dev)
5331 		dev_put(dev);
5332 	if (fillargs.netnsid >= 0)
5333 		put_net(tgt_net);
5334 
5335 	return err;
5336 }
5337 
5338 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
5339 {
5340 	struct sk_buff *skb;
5341 	struct net *net = dev_net(ifa->idev->dev);
5342 	struct inet6_fill_args fillargs = {
5343 		.portid = 0,
5344 		.seq = 0,
5345 		.event = event,
5346 		.flags = 0,
5347 		.netnsid = -1,
5348 	};
5349 	int err = -ENOBUFS;
5350 
5351 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
5352 	if (!skb)
5353 		goto errout;
5354 
5355 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5356 	if (err < 0) {
5357 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5358 		WARN_ON(err == -EMSGSIZE);
5359 		kfree_skb(skb);
5360 		goto errout;
5361 	}
5362 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5363 	return;
5364 errout:
5365 	if (err < 0)
5366 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5367 }
5368 
5369 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
5370 				__s32 *array, int bytes)
5371 {
5372 	BUG_ON(bytes < (DEVCONF_MAX * 4));
5373 
5374 	memset(array, 0, bytes);
5375 	array[DEVCONF_FORWARDING] = cnf->forwarding;
5376 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
5377 	array[DEVCONF_MTU6] = cnf->mtu6;
5378 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
5379 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
5380 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
5381 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
5382 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
5383 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5384 		jiffies_to_msecs(cnf->rtr_solicit_interval);
5385 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5386 		jiffies_to_msecs(cnf->rtr_solicit_max_interval);
5387 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5388 		jiffies_to_msecs(cnf->rtr_solicit_delay);
5389 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
5390 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5391 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
5392 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5393 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
5394 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
5395 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
5396 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
5397 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
5398 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
5399 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
5400 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
5401 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] = cnf->accept_ra_min_hop_limit;
5402 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
5403 #ifdef CONFIG_IPV6_ROUTER_PREF
5404 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
5405 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5406 		jiffies_to_msecs(cnf->rtr_probe_interval);
5407 #ifdef CONFIG_IPV6_ROUTE_INFO
5408 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] = cnf->accept_ra_rt_info_min_plen;
5409 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
5410 #endif
5411 #endif
5412 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
5413 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
5414 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5415 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
5416 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
5417 #endif
5418 #ifdef CONFIG_IPV6_MROUTE
5419 	array[DEVCONF_MC_FORWARDING] = cnf->mc_forwarding;
5420 #endif
5421 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
5422 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
5423 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
5424 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
5425 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
5426 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
5427 	array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
5428 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] = cnf->ignore_routes_with_linkdown;
5429 	/* we omit DEVCONF_STABLE_SECRET for now */
5430 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
5431 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
5432 	array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
5433 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
5434 	array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
5435 #ifdef CONFIG_IPV6_SEG6_HMAC
5436 	array[DEVCONF_SEG6_REQUIRE_HMAC] = cnf->seg6_require_hmac;
5437 #endif
5438 	array[DEVCONF_ENHANCED_DAD] = cnf->enhanced_dad;
5439 	array[DEVCONF_ADDR_GEN_MODE] = cnf->addr_gen_mode;
5440 	array[DEVCONF_DISABLE_POLICY] = cnf->disable_policy;
5441 	array[DEVCONF_NDISC_TCLASS] = cnf->ndisc_tclass;
5442 }
5443 
5444 static inline size_t inet6_ifla6_size(void)
5445 {
5446 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5447 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5448 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5449 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5450 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5451 	     + nla_total_size(sizeof(struct in6_addr)) /* IFLA_INET6_TOKEN */
5452 	     + nla_total_size(1) /* IFLA_INET6_ADDR_GEN_MODE */
5453 	     + 0;
5454 }
5455 
5456 static inline size_t inet6_if_nlmsg_size(void)
5457 {
5458 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5459 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5460 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5461 	       + nla_total_size(4) /* IFLA_MTU */
5462 	       + nla_total_size(4) /* IFLA_LINK */
5463 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5464 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5465 }
5466 
5467 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5468 					int bytes)
5469 {
5470 	int i;
5471 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5472 	BUG_ON(pad < 0);
5473 
5474 	/* Use put_unaligned() because stats may not be aligned for u64. */
5475 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5476 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5477 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5478 
5479 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5480 }
5481 
5482 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5483 					int bytes, size_t syncpoff)
5484 {
5485 	int i, c;
5486 	u64 buff[IPSTATS_MIB_MAX];
5487 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5488 
5489 	BUG_ON(pad < 0);
5490 
5491 	memset(buff, 0, sizeof(buff));
5492 	buff[0] = IPSTATS_MIB_MAX;
5493 
5494 	for_each_possible_cpu(c) {
5495 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5496 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5497 	}
5498 
5499 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5500 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5501 }
5502 
5503 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5504 			     int bytes)
5505 {
5506 	switch (attrtype) {
5507 	case IFLA_INET6_STATS:
5508 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5509 				     offsetof(struct ipstats_mib, syncp));
5510 		break;
5511 	case IFLA_INET6_ICMP6STATS:
5512 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5513 		break;
5514 	}
5515 }
5516 
5517 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5518 				  u32 ext_filter_mask)
5519 {
5520 	struct nlattr *nla;
5521 	struct ifla_cacheinfo ci;
5522 
5523 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
5524 		goto nla_put_failure;
5525 	ci.max_reasm_len = IPV6_MAXPLEN;
5526 	ci.tstamp = cstamp_delta(idev->tstamp);
5527 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5528 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5529 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5530 		goto nla_put_failure;
5531 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5532 	if (!nla)
5533 		goto nla_put_failure;
5534 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5535 
5536 	/* XXX - MC not implemented */
5537 
5538 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5539 		return 0;
5540 
5541 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5542 	if (!nla)
5543 		goto nla_put_failure;
5544 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5545 
5546 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5547 	if (!nla)
5548 		goto nla_put_failure;
5549 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5550 
5551 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5552 	if (!nla)
5553 		goto nla_put_failure;
5554 
5555 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->cnf.addr_gen_mode))
5556 		goto nla_put_failure;
5557 
5558 	read_lock_bh(&idev->lock);
5559 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5560 	read_unlock_bh(&idev->lock);
5561 
5562 	return 0;
5563 
5564 nla_put_failure:
5565 	return -EMSGSIZE;
5566 }
5567 
5568 static size_t inet6_get_link_af_size(const struct net_device *dev,
5569 				     u32 ext_filter_mask)
5570 {
5571 	if (!__in6_dev_get(dev))
5572 		return 0;
5573 
5574 	return inet6_ifla6_size();
5575 }
5576 
5577 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5578 			      u32 ext_filter_mask)
5579 {
5580 	struct inet6_dev *idev = __in6_dev_get(dev);
5581 
5582 	if (!idev)
5583 		return -ENODATA;
5584 
5585 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5586 		return -EMSGSIZE;
5587 
5588 	return 0;
5589 }
5590 
5591 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token)
5592 {
5593 	struct inet6_ifaddr *ifp;
5594 	struct net_device *dev = idev->dev;
5595 	bool clear_token, update_rs = false;
5596 	struct in6_addr ll_addr;
5597 
5598 	ASSERT_RTNL();
5599 
5600 	if (!token)
5601 		return -EINVAL;
5602 	if (dev->flags & (IFF_LOOPBACK | IFF_NOARP))
5603 		return -EINVAL;
5604 	if (!ipv6_accept_ra(idev))
5605 		return -EINVAL;
5606 	if (idev->cnf.rtr_solicits == 0)
5607 		return -EINVAL;
5608 
5609 	write_lock_bh(&idev->lock);
5610 
5611 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5612 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5613 
5614 	write_unlock_bh(&idev->lock);
5615 
5616 	clear_token = ipv6_addr_any(token);
5617 	if (clear_token)
5618 		goto update_lft;
5619 
5620 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5621 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5622 			     IFA_F_OPTIMISTIC)) {
5623 		/* If we're not ready, then normal ifup will take care
5624 		 * of this. Otherwise, we need to request our rs here.
5625 		 */
5626 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5627 		update_rs = true;
5628 	}
5629 
5630 update_lft:
5631 	write_lock_bh(&idev->lock);
5632 
5633 	if (update_rs) {
5634 		idev->if_flags |= IF_RS_SENT;
5635 		idev->rs_interval = rfc3315_s14_backoff_init(
5636 			idev->cnf.rtr_solicit_interval);
5637 		idev->rs_probes = 1;
5638 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5639 	}
5640 
5641 	/* Well, that's kinda nasty ... */
5642 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5643 		spin_lock(&ifp->lock);
5644 		if (ifp->tokenized) {
5645 			ifp->valid_lft = 0;
5646 			ifp->prefered_lft = 0;
5647 		}
5648 		spin_unlock(&ifp->lock);
5649 	}
5650 
5651 	write_unlock_bh(&idev->lock);
5652 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5653 	addrconf_verify_rtnl();
5654 	return 0;
5655 }
5656 
5657 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5658 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5659 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5660 };
5661 
5662 static int inet6_validate_link_af(const struct net_device *dev,
5663 				  const struct nlattr *nla)
5664 {
5665 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5666 
5667 	if (dev && !__in6_dev_get(dev))
5668 		return -EAFNOSUPPORT;
5669 
5670 	return nla_parse_nested(tb, IFLA_INET6_MAX, nla, inet6_af_policy,
5671 				NULL);
5672 }
5673 
5674 static int check_addr_gen_mode(int mode)
5675 {
5676 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5677 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5678 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5679 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5680 		return -EINVAL;
5681 	return 1;
5682 }
5683 
5684 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5685 				int mode)
5686 {
5687 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5688 	    !idev->cnf.stable_secret.initialized &&
5689 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5690 		return -EINVAL;
5691 	return 1;
5692 }
5693 
5694 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla)
5695 {
5696 	int err = -EINVAL;
5697 	struct inet6_dev *idev = __in6_dev_get(dev);
5698 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5699 
5700 	if (!idev)
5701 		return -EAFNOSUPPORT;
5702 
5703 	if (nla_parse_nested(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
5704 		BUG();
5705 
5706 	if (tb[IFLA_INET6_TOKEN]) {
5707 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]));
5708 		if (err)
5709 			return err;
5710 	}
5711 
5712 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5713 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5714 
5715 		if (check_addr_gen_mode(mode) < 0 ||
5716 		    check_stable_privacy(idev, dev_net(dev), mode) < 0)
5717 			return -EINVAL;
5718 
5719 		idev->cnf.addr_gen_mode = mode;
5720 		err = 0;
5721 	}
5722 
5723 	return err;
5724 }
5725 
5726 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
5727 			     u32 portid, u32 seq, int event, unsigned int flags)
5728 {
5729 	struct net_device *dev = idev->dev;
5730 	struct ifinfomsg *hdr;
5731 	struct nlmsghdr *nlh;
5732 	void *protoinfo;
5733 
5734 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
5735 	if (!nlh)
5736 		return -EMSGSIZE;
5737 
5738 	hdr = nlmsg_data(nlh);
5739 	hdr->ifi_family = AF_INET6;
5740 	hdr->__ifi_pad = 0;
5741 	hdr->ifi_type = dev->type;
5742 	hdr->ifi_index = dev->ifindex;
5743 	hdr->ifi_flags = dev_get_flags(dev);
5744 	hdr->ifi_change = 0;
5745 
5746 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
5747 	    (dev->addr_len &&
5748 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
5749 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
5750 	    (dev->ifindex != dev_get_iflink(dev) &&
5751 	     nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))) ||
5752 	    nla_put_u8(skb, IFLA_OPERSTATE,
5753 		       netif_running(dev) ? dev->operstate : IF_OPER_DOWN))
5754 		goto nla_put_failure;
5755 	protoinfo = nla_nest_start(skb, IFLA_PROTINFO);
5756 	if (!protoinfo)
5757 		goto nla_put_failure;
5758 
5759 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
5760 		goto nla_put_failure;
5761 
5762 	nla_nest_end(skb, protoinfo);
5763 	nlmsg_end(skb, nlh);
5764 	return 0;
5765 
5766 nla_put_failure:
5767 	nlmsg_cancel(skb, nlh);
5768 	return -EMSGSIZE;
5769 }
5770 
5771 static int inet6_valid_dump_ifinfo(const struct nlmsghdr *nlh,
5772 				   struct netlink_ext_ack *extack)
5773 {
5774 	struct ifinfomsg *ifm;
5775 
5776 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5777 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for link dump request");
5778 		return -EINVAL;
5779 	}
5780 
5781 	if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
5782 		NL_SET_ERR_MSG_MOD(extack, "Invalid data after header");
5783 		return -EINVAL;
5784 	}
5785 
5786 	ifm = nlmsg_data(nlh);
5787 	if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
5788 	    ifm->ifi_change || ifm->ifi_index) {
5789 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for dump request");
5790 		return -EINVAL;
5791 	}
5792 
5793 	return 0;
5794 }
5795 
5796 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
5797 {
5798 	struct net *net = sock_net(skb->sk);
5799 	int h, s_h;
5800 	int idx = 0, s_idx;
5801 	struct net_device *dev;
5802 	struct inet6_dev *idev;
5803 	struct hlist_head *head;
5804 
5805 	/* only requests using strict checking can pass data to
5806 	 * influence the dump
5807 	 */
5808 	if (cb->strict_check) {
5809 		int err = inet6_valid_dump_ifinfo(cb->nlh, cb->extack);
5810 
5811 		if (err < 0)
5812 			return err;
5813 	}
5814 
5815 	s_h = cb->args[0];
5816 	s_idx = cb->args[1];
5817 
5818 	rcu_read_lock();
5819 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5820 		idx = 0;
5821 		head = &net->dev_index_head[h];
5822 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5823 			if (idx < s_idx)
5824 				goto cont;
5825 			idev = __in6_dev_get(dev);
5826 			if (!idev)
5827 				goto cont;
5828 			if (inet6_fill_ifinfo(skb, idev,
5829 					      NETLINK_CB(cb->skb).portid,
5830 					      cb->nlh->nlmsg_seq,
5831 					      RTM_NEWLINK, NLM_F_MULTI) < 0)
5832 				goto out;
5833 cont:
5834 			idx++;
5835 		}
5836 	}
5837 out:
5838 	rcu_read_unlock();
5839 	cb->args[1] = idx;
5840 	cb->args[0] = h;
5841 
5842 	return skb->len;
5843 }
5844 
5845 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
5846 {
5847 	struct sk_buff *skb;
5848 	struct net *net = dev_net(idev->dev);
5849 	int err = -ENOBUFS;
5850 
5851 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
5852 	if (!skb)
5853 		goto errout;
5854 
5855 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
5856 	if (err < 0) {
5857 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
5858 		WARN_ON(err == -EMSGSIZE);
5859 		kfree_skb(skb);
5860 		goto errout;
5861 	}
5862 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
5863 	return;
5864 errout:
5865 	if (err < 0)
5866 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
5867 }
5868 
5869 static inline size_t inet6_prefix_nlmsg_size(void)
5870 {
5871 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
5872 	       + nla_total_size(sizeof(struct in6_addr))
5873 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
5874 }
5875 
5876 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
5877 			     struct prefix_info *pinfo, u32 portid, u32 seq,
5878 			     int event, unsigned int flags)
5879 {
5880 	struct prefixmsg *pmsg;
5881 	struct nlmsghdr *nlh;
5882 	struct prefix_cacheinfo	ci;
5883 
5884 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
5885 	if (!nlh)
5886 		return -EMSGSIZE;
5887 
5888 	pmsg = nlmsg_data(nlh);
5889 	pmsg->prefix_family = AF_INET6;
5890 	pmsg->prefix_pad1 = 0;
5891 	pmsg->prefix_pad2 = 0;
5892 	pmsg->prefix_ifindex = idev->dev->ifindex;
5893 	pmsg->prefix_len = pinfo->prefix_len;
5894 	pmsg->prefix_type = pinfo->type;
5895 	pmsg->prefix_pad3 = 0;
5896 	pmsg->prefix_flags = 0;
5897 	if (pinfo->onlink)
5898 		pmsg->prefix_flags |= IF_PREFIX_ONLINK;
5899 	if (pinfo->autoconf)
5900 		pmsg->prefix_flags |= IF_PREFIX_AUTOCONF;
5901 
5902 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
5903 		goto nla_put_failure;
5904 	ci.preferred_time = ntohl(pinfo->prefered);
5905 	ci.valid_time = ntohl(pinfo->valid);
5906 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
5907 		goto nla_put_failure;
5908 	nlmsg_end(skb, nlh);
5909 	return 0;
5910 
5911 nla_put_failure:
5912 	nlmsg_cancel(skb, nlh);
5913 	return -EMSGSIZE;
5914 }
5915 
5916 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
5917 			 struct prefix_info *pinfo)
5918 {
5919 	struct sk_buff *skb;
5920 	struct net *net = dev_net(idev->dev);
5921 	int err = -ENOBUFS;
5922 
5923 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
5924 	if (!skb)
5925 		goto errout;
5926 
5927 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
5928 	if (err < 0) {
5929 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
5930 		WARN_ON(err == -EMSGSIZE);
5931 		kfree_skb(skb);
5932 		goto errout;
5933 	}
5934 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
5935 	return;
5936 errout:
5937 	if (err < 0)
5938 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
5939 }
5940 
5941 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5942 {
5943 	struct net *net = dev_net(ifp->idev->dev);
5944 
5945 	if (event)
5946 		ASSERT_RTNL();
5947 
5948 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
5949 
5950 	switch (event) {
5951 	case RTM_NEWADDR:
5952 		/*
5953 		 * If the address was optimistic
5954 		 * we inserted the route at the start of
5955 		 * our DAD process, so we don't need
5956 		 * to do it again
5957 		 */
5958 		if (!rcu_access_pointer(ifp->rt->fib6_node))
5959 			ip6_ins_rt(net, ifp->rt);
5960 		if (ifp->idev->cnf.forwarding)
5961 			addrconf_join_anycast(ifp);
5962 		if (!ipv6_addr_any(&ifp->peer_addr))
5963 			addrconf_prefix_route(&ifp->peer_addr, 128, 0,
5964 					      ifp->idev->dev, 0, 0,
5965 					      GFP_ATOMIC);
5966 		break;
5967 	case RTM_DELADDR:
5968 		if (ifp->idev->cnf.forwarding)
5969 			addrconf_leave_anycast(ifp);
5970 		addrconf_leave_solict(ifp->idev, &ifp->addr);
5971 		if (!ipv6_addr_any(&ifp->peer_addr)) {
5972 			struct fib6_info *rt;
5973 
5974 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
5975 						       ifp->idev->dev, 0, 0,
5976 						       false);
5977 			if (rt)
5978 				ip6_del_rt(net, rt);
5979 		}
5980 		if (ifp->rt) {
5981 			ip6_del_rt(net, ifp->rt);
5982 			ifp->rt = NULL;
5983 		}
5984 		rt_genid_bump_ipv6(net);
5985 		break;
5986 	}
5987 	atomic_inc(&net->ipv6.dev_addr_genid);
5988 }
5989 
5990 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
5991 {
5992 	rcu_read_lock_bh();
5993 	if (likely(ifp->idev->dead == 0))
5994 		__ipv6_ifa_notify(event, ifp);
5995 	rcu_read_unlock_bh();
5996 }
5997 
5998 #ifdef CONFIG_SYSCTL
5999 
6000 static
6001 int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
6002 			   void __user *buffer, size_t *lenp, loff_t *ppos)
6003 {
6004 	int *valp = ctl->data;
6005 	int val = *valp;
6006 	loff_t pos = *ppos;
6007 	struct ctl_table lctl;
6008 	int ret;
6009 
6010 	/*
6011 	 * ctl->data points to idev->cnf.forwarding, we should
6012 	 * not modify it until we get the rtnl lock.
6013 	 */
6014 	lctl = *ctl;
6015 	lctl.data = &val;
6016 
6017 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6018 
6019 	if (write)
6020 		ret = addrconf_fixup_forwarding(ctl, valp, val);
6021 	if (ret)
6022 		*ppos = pos;
6023 	return ret;
6024 }
6025 
6026 static
6027 int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
6028 			void __user *buffer, size_t *lenp, loff_t *ppos)
6029 {
6030 	struct inet6_dev *idev = ctl->extra1;
6031 	int min_mtu = IPV6_MIN_MTU;
6032 	struct ctl_table lctl;
6033 
6034 	lctl = *ctl;
6035 	lctl.extra1 = &min_mtu;
6036 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
6037 
6038 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
6039 }
6040 
6041 static void dev_disable_change(struct inet6_dev *idev)
6042 {
6043 	struct netdev_notifier_info info;
6044 
6045 	if (!idev || !idev->dev)
6046 		return;
6047 
6048 	netdev_notifier_info_init(&info, idev->dev);
6049 	if (idev->cnf.disable_ipv6)
6050 		addrconf_notify(NULL, NETDEV_DOWN, &info);
6051 	else
6052 		addrconf_notify(NULL, NETDEV_UP, &info);
6053 }
6054 
6055 static void addrconf_disable_change(struct net *net, __s32 newf)
6056 {
6057 	struct net_device *dev;
6058 	struct inet6_dev *idev;
6059 
6060 	for_each_netdev(net, dev) {
6061 		idev = __in6_dev_get(dev);
6062 		if (idev) {
6063 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
6064 			idev->cnf.disable_ipv6 = newf;
6065 			if (changed)
6066 				dev_disable_change(idev);
6067 		}
6068 	}
6069 }
6070 
6071 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
6072 {
6073 	struct net *net;
6074 	int old;
6075 
6076 	if (!rtnl_trylock())
6077 		return restart_syscall();
6078 
6079 	net = (struct net *)table->extra2;
6080 	old = *p;
6081 	*p = newf;
6082 
6083 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
6084 		rtnl_unlock();
6085 		return 0;
6086 	}
6087 
6088 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
6089 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
6090 		addrconf_disable_change(net, newf);
6091 	} else if ((!newf) ^ (!old))
6092 		dev_disable_change((struct inet6_dev *)table->extra1);
6093 
6094 	rtnl_unlock();
6095 	return 0;
6096 }
6097 
6098 static
6099 int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
6100 			    void __user *buffer, size_t *lenp, loff_t *ppos)
6101 {
6102 	int *valp = ctl->data;
6103 	int val = *valp;
6104 	loff_t pos = *ppos;
6105 	struct ctl_table lctl;
6106 	int ret;
6107 
6108 	/*
6109 	 * ctl->data points to idev->cnf.disable_ipv6, we should
6110 	 * not modify it until we get the rtnl lock.
6111 	 */
6112 	lctl = *ctl;
6113 	lctl.data = &val;
6114 
6115 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6116 
6117 	if (write)
6118 		ret = addrconf_disable_ipv6(ctl, valp, val);
6119 	if (ret)
6120 		*ppos = pos;
6121 	return ret;
6122 }
6123 
6124 static
6125 int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
6126 			      void __user *buffer, size_t *lenp, loff_t *ppos)
6127 {
6128 	int *valp = ctl->data;
6129 	int ret;
6130 	int old, new;
6131 
6132 	old = *valp;
6133 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
6134 	new = *valp;
6135 
6136 	if (write && old != new) {
6137 		struct net *net = ctl->extra2;
6138 
6139 		if (!rtnl_trylock())
6140 			return restart_syscall();
6141 
6142 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
6143 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6144 						     NETCONFA_PROXY_NEIGH,
6145 						     NETCONFA_IFINDEX_DEFAULT,
6146 						     net->ipv6.devconf_dflt);
6147 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
6148 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6149 						     NETCONFA_PROXY_NEIGH,
6150 						     NETCONFA_IFINDEX_ALL,
6151 						     net->ipv6.devconf_all);
6152 		else {
6153 			struct inet6_dev *idev = ctl->extra1;
6154 
6155 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6156 						     NETCONFA_PROXY_NEIGH,
6157 						     idev->dev->ifindex,
6158 						     &idev->cnf);
6159 		}
6160 		rtnl_unlock();
6161 	}
6162 
6163 	return ret;
6164 }
6165 
6166 static int addrconf_sysctl_addr_gen_mode(struct ctl_table *ctl, int write,
6167 					 void __user *buffer, size_t *lenp,
6168 					 loff_t *ppos)
6169 {
6170 	int ret = 0;
6171 	u32 new_val;
6172 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
6173 	struct net *net = (struct net *)ctl->extra2;
6174 	struct ctl_table tmp = {
6175 		.data = &new_val,
6176 		.maxlen = sizeof(new_val),
6177 		.mode = ctl->mode,
6178 	};
6179 
6180 	if (!rtnl_trylock())
6181 		return restart_syscall();
6182 
6183 	new_val = *((u32 *)ctl->data);
6184 
6185 	ret = proc_douintvec(&tmp, write, buffer, lenp, ppos);
6186 	if (ret != 0)
6187 		goto out;
6188 
6189 	if (write) {
6190 		if (check_addr_gen_mode(new_val) < 0) {
6191 			ret = -EINVAL;
6192 			goto out;
6193 		}
6194 
6195 		if (idev) {
6196 			if (check_stable_privacy(idev, net, new_val) < 0) {
6197 				ret = -EINVAL;
6198 				goto out;
6199 			}
6200 
6201 			if (idev->cnf.addr_gen_mode != new_val) {
6202 				idev->cnf.addr_gen_mode = new_val;
6203 				addrconf_dev_config(idev->dev);
6204 			}
6205 		} else if (&net->ipv6.devconf_all->addr_gen_mode == ctl->data) {
6206 			struct net_device *dev;
6207 
6208 			net->ipv6.devconf_dflt->addr_gen_mode = new_val;
6209 			for_each_netdev(net, dev) {
6210 				idev = __in6_dev_get(dev);
6211 				if (idev &&
6212 				    idev->cnf.addr_gen_mode != new_val) {
6213 					idev->cnf.addr_gen_mode = new_val;
6214 					addrconf_dev_config(idev->dev);
6215 				}
6216 			}
6217 		}
6218 
6219 		*((u32 *)ctl->data) = new_val;
6220 	}
6221 
6222 out:
6223 	rtnl_unlock();
6224 
6225 	return ret;
6226 }
6227 
6228 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
6229 					 void __user *buffer, size_t *lenp,
6230 					 loff_t *ppos)
6231 {
6232 	int err;
6233 	struct in6_addr addr;
6234 	char str[IPV6_MAX_STRLEN];
6235 	struct ctl_table lctl = *ctl;
6236 	struct net *net = ctl->extra2;
6237 	struct ipv6_stable_secret *secret = ctl->data;
6238 
6239 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
6240 		return -EIO;
6241 
6242 	lctl.maxlen = IPV6_MAX_STRLEN;
6243 	lctl.data = str;
6244 
6245 	if (!rtnl_trylock())
6246 		return restart_syscall();
6247 
6248 	if (!write && !secret->initialized) {
6249 		err = -EIO;
6250 		goto out;
6251 	}
6252 
6253 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
6254 	if (err >= sizeof(str)) {
6255 		err = -EIO;
6256 		goto out;
6257 	}
6258 
6259 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
6260 	if (err || !write)
6261 		goto out;
6262 
6263 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
6264 		err = -EIO;
6265 		goto out;
6266 	}
6267 
6268 	secret->initialized = true;
6269 	secret->secret = addr;
6270 
6271 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
6272 		struct net_device *dev;
6273 
6274 		for_each_netdev(net, dev) {
6275 			struct inet6_dev *idev = __in6_dev_get(dev);
6276 
6277 			if (idev) {
6278 				idev->cnf.addr_gen_mode =
6279 					IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6280 			}
6281 		}
6282 	} else {
6283 		struct inet6_dev *idev = ctl->extra1;
6284 
6285 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6286 	}
6287 
6288 out:
6289 	rtnl_unlock();
6290 
6291 	return err;
6292 }
6293 
6294 static
6295 int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
6296 						int write,
6297 						void __user *buffer,
6298 						size_t *lenp,
6299 						loff_t *ppos)
6300 {
6301 	int *valp = ctl->data;
6302 	int val = *valp;
6303 	loff_t pos = *ppos;
6304 	struct ctl_table lctl;
6305 	int ret;
6306 
6307 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
6308 	 * we should not modify it until we get the rtnl lock.
6309 	 */
6310 	lctl = *ctl;
6311 	lctl.data = &val;
6312 
6313 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6314 
6315 	if (write)
6316 		ret = addrconf_fixup_linkdown(ctl, valp, val);
6317 	if (ret)
6318 		*ppos = pos;
6319 	return ret;
6320 }
6321 
6322 static
6323 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
6324 {
6325 	if (rt) {
6326 		if (action)
6327 			rt->dst.flags |= DST_NOPOLICY;
6328 		else
6329 			rt->dst.flags &= ~DST_NOPOLICY;
6330 	}
6331 }
6332 
6333 static
6334 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
6335 {
6336 	struct inet6_ifaddr *ifa;
6337 
6338 	read_lock_bh(&idev->lock);
6339 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
6340 		spin_lock(&ifa->lock);
6341 		if (ifa->rt) {
6342 			struct fib6_info *rt = ifa->rt;
6343 			int cpu;
6344 
6345 			rcu_read_lock();
6346 			ifa->rt->dst_nopolicy = val ? true : false;
6347 			if (rt->rt6i_pcpu) {
6348 				for_each_possible_cpu(cpu) {
6349 					struct rt6_info **rtp;
6350 
6351 					rtp = per_cpu_ptr(rt->rt6i_pcpu, cpu);
6352 					addrconf_set_nopolicy(*rtp, val);
6353 				}
6354 			}
6355 			rcu_read_unlock();
6356 		}
6357 		spin_unlock(&ifa->lock);
6358 	}
6359 	read_unlock_bh(&idev->lock);
6360 }
6361 
6362 static
6363 int addrconf_disable_policy(struct ctl_table *ctl, int *valp, int val)
6364 {
6365 	struct inet6_dev *idev;
6366 	struct net *net;
6367 
6368 	if (!rtnl_trylock())
6369 		return restart_syscall();
6370 
6371 	*valp = val;
6372 
6373 	net = (struct net *)ctl->extra2;
6374 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
6375 		rtnl_unlock();
6376 		return 0;
6377 	}
6378 
6379 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
6380 		struct net_device *dev;
6381 
6382 		for_each_netdev(net, dev) {
6383 			idev = __in6_dev_get(dev);
6384 			if (idev)
6385 				addrconf_disable_policy_idev(idev, val);
6386 		}
6387 	} else {
6388 		idev = (struct inet6_dev *)ctl->extra1;
6389 		addrconf_disable_policy_idev(idev, val);
6390 	}
6391 
6392 	rtnl_unlock();
6393 	return 0;
6394 }
6395 
6396 static
6397 int addrconf_sysctl_disable_policy(struct ctl_table *ctl, int write,
6398 				   void __user *buffer, size_t *lenp,
6399 				   loff_t *ppos)
6400 {
6401 	int *valp = ctl->data;
6402 	int val = *valp;
6403 	loff_t pos = *ppos;
6404 	struct ctl_table lctl;
6405 	int ret;
6406 
6407 	lctl = *ctl;
6408 	lctl.data = &val;
6409 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6410 
6411 	if (write && (*valp != val))
6412 		ret = addrconf_disable_policy(ctl, valp, val);
6413 
6414 	if (ret)
6415 		*ppos = pos;
6416 
6417 	return ret;
6418 }
6419 
6420 static int minus_one = -1;
6421 static const int zero = 0;
6422 static const int one = 1;
6423 static const int two_five_five = 255;
6424 
6425 static const struct ctl_table addrconf_sysctl[] = {
6426 	{
6427 		.procname	= "forwarding",
6428 		.data		= &ipv6_devconf.forwarding,
6429 		.maxlen		= sizeof(int),
6430 		.mode		= 0644,
6431 		.proc_handler	= addrconf_sysctl_forward,
6432 	},
6433 	{
6434 		.procname	= "hop_limit",
6435 		.data		= &ipv6_devconf.hop_limit,
6436 		.maxlen		= sizeof(int),
6437 		.mode		= 0644,
6438 		.proc_handler	= proc_dointvec_minmax,
6439 		.extra1		= (void *)&one,
6440 		.extra2		= (void *)&two_five_five,
6441 	},
6442 	{
6443 		.procname	= "mtu",
6444 		.data		= &ipv6_devconf.mtu6,
6445 		.maxlen		= sizeof(int),
6446 		.mode		= 0644,
6447 		.proc_handler	= addrconf_sysctl_mtu,
6448 	},
6449 	{
6450 		.procname	= "accept_ra",
6451 		.data		= &ipv6_devconf.accept_ra,
6452 		.maxlen		= sizeof(int),
6453 		.mode		= 0644,
6454 		.proc_handler	= proc_dointvec,
6455 	},
6456 	{
6457 		.procname	= "accept_redirects",
6458 		.data		= &ipv6_devconf.accept_redirects,
6459 		.maxlen		= sizeof(int),
6460 		.mode		= 0644,
6461 		.proc_handler	= proc_dointvec,
6462 	},
6463 	{
6464 		.procname	= "autoconf",
6465 		.data		= &ipv6_devconf.autoconf,
6466 		.maxlen		= sizeof(int),
6467 		.mode		= 0644,
6468 		.proc_handler	= proc_dointvec,
6469 	},
6470 	{
6471 		.procname	= "dad_transmits",
6472 		.data		= &ipv6_devconf.dad_transmits,
6473 		.maxlen		= sizeof(int),
6474 		.mode		= 0644,
6475 		.proc_handler	= proc_dointvec,
6476 	},
6477 	{
6478 		.procname	= "router_solicitations",
6479 		.data		= &ipv6_devconf.rtr_solicits,
6480 		.maxlen		= sizeof(int),
6481 		.mode		= 0644,
6482 		.proc_handler	= proc_dointvec_minmax,
6483 		.extra1		= &minus_one,
6484 	},
6485 	{
6486 		.procname	= "router_solicitation_interval",
6487 		.data		= &ipv6_devconf.rtr_solicit_interval,
6488 		.maxlen		= sizeof(int),
6489 		.mode		= 0644,
6490 		.proc_handler	= proc_dointvec_jiffies,
6491 	},
6492 	{
6493 		.procname	= "router_solicitation_max_interval",
6494 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6495 		.maxlen		= sizeof(int),
6496 		.mode		= 0644,
6497 		.proc_handler	= proc_dointvec_jiffies,
6498 	},
6499 	{
6500 		.procname	= "router_solicitation_delay",
6501 		.data		= &ipv6_devconf.rtr_solicit_delay,
6502 		.maxlen		= sizeof(int),
6503 		.mode		= 0644,
6504 		.proc_handler	= proc_dointvec_jiffies,
6505 	},
6506 	{
6507 		.procname	= "force_mld_version",
6508 		.data		= &ipv6_devconf.force_mld_version,
6509 		.maxlen		= sizeof(int),
6510 		.mode		= 0644,
6511 		.proc_handler	= proc_dointvec,
6512 	},
6513 	{
6514 		.procname	= "mldv1_unsolicited_report_interval",
6515 		.data		=
6516 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6517 		.maxlen		= sizeof(int),
6518 		.mode		= 0644,
6519 		.proc_handler	= proc_dointvec_ms_jiffies,
6520 	},
6521 	{
6522 		.procname	= "mldv2_unsolicited_report_interval",
6523 		.data		=
6524 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6525 		.maxlen		= sizeof(int),
6526 		.mode		= 0644,
6527 		.proc_handler	= proc_dointvec_ms_jiffies,
6528 	},
6529 	{
6530 		.procname	= "use_tempaddr",
6531 		.data		= &ipv6_devconf.use_tempaddr,
6532 		.maxlen		= sizeof(int),
6533 		.mode		= 0644,
6534 		.proc_handler	= proc_dointvec,
6535 	},
6536 	{
6537 		.procname	= "temp_valid_lft",
6538 		.data		= &ipv6_devconf.temp_valid_lft,
6539 		.maxlen		= sizeof(int),
6540 		.mode		= 0644,
6541 		.proc_handler	= proc_dointvec,
6542 	},
6543 	{
6544 		.procname	= "temp_prefered_lft",
6545 		.data		= &ipv6_devconf.temp_prefered_lft,
6546 		.maxlen		= sizeof(int),
6547 		.mode		= 0644,
6548 		.proc_handler	= proc_dointvec,
6549 	},
6550 	{
6551 		.procname	= "regen_max_retry",
6552 		.data		= &ipv6_devconf.regen_max_retry,
6553 		.maxlen		= sizeof(int),
6554 		.mode		= 0644,
6555 		.proc_handler	= proc_dointvec,
6556 	},
6557 	{
6558 		.procname	= "max_desync_factor",
6559 		.data		= &ipv6_devconf.max_desync_factor,
6560 		.maxlen		= sizeof(int),
6561 		.mode		= 0644,
6562 		.proc_handler	= proc_dointvec,
6563 	},
6564 	{
6565 		.procname	= "max_addresses",
6566 		.data		= &ipv6_devconf.max_addresses,
6567 		.maxlen		= sizeof(int),
6568 		.mode		= 0644,
6569 		.proc_handler	= proc_dointvec,
6570 	},
6571 	{
6572 		.procname	= "accept_ra_defrtr",
6573 		.data		= &ipv6_devconf.accept_ra_defrtr,
6574 		.maxlen		= sizeof(int),
6575 		.mode		= 0644,
6576 		.proc_handler	= proc_dointvec,
6577 	},
6578 	{
6579 		.procname	= "accept_ra_min_hop_limit",
6580 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6581 		.maxlen		= sizeof(int),
6582 		.mode		= 0644,
6583 		.proc_handler	= proc_dointvec,
6584 	},
6585 	{
6586 		.procname	= "accept_ra_pinfo",
6587 		.data		= &ipv6_devconf.accept_ra_pinfo,
6588 		.maxlen		= sizeof(int),
6589 		.mode		= 0644,
6590 		.proc_handler	= proc_dointvec,
6591 	},
6592 #ifdef CONFIG_IPV6_ROUTER_PREF
6593 	{
6594 		.procname	= "accept_ra_rtr_pref",
6595 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6596 		.maxlen		= sizeof(int),
6597 		.mode		= 0644,
6598 		.proc_handler	= proc_dointvec,
6599 	},
6600 	{
6601 		.procname	= "router_probe_interval",
6602 		.data		= &ipv6_devconf.rtr_probe_interval,
6603 		.maxlen		= sizeof(int),
6604 		.mode		= 0644,
6605 		.proc_handler	= proc_dointvec_jiffies,
6606 	},
6607 #ifdef CONFIG_IPV6_ROUTE_INFO
6608 	{
6609 		.procname	= "accept_ra_rt_info_min_plen",
6610 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6611 		.maxlen		= sizeof(int),
6612 		.mode		= 0644,
6613 		.proc_handler	= proc_dointvec,
6614 	},
6615 	{
6616 		.procname	= "accept_ra_rt_info_max_plen",
6617 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6618 		.maxlen		= sizeof(int),
6619 		.mode		= 0644,
6620 		.proc_handler	= proc_dointvec,
6621 	},
6622 #endif
6623 #endif
6624 	{
6625 		.procname	= "proxy_ndp",
6626 		.data		= &ipv6_devconf.proxy_ndp,
6627 		.maxlen		= sizeof(int),
6628 		.mode		= 0644,
6629 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6630 	},
6631 	{
6632 		.procname	= "accept_source_route",
6633 		.data		= &ipv6_devconf.accept_source_route,
6634 		.maxlen		= sizeof(int),
6635 		.mode		= 0644,
6636 		.proc_handler	= proc_dointvec,
6637 	},
6638 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
6639 	{
6640 		.procname	= "optimistic_dad",
6641 		.data		= &ipv6_devconf.optimistic_dad,
6642 		.maxlen		= sizeof(int),
6643 		.mode		= 0644,
6644 		.proc_handler   = proc_dointvec,
6645 	},
6646 	{
6647 		.procname	= "use_optimistic",
6648 		.data		= &ipv6_devconf.use_optimistic,
6649 		.maxlen		= sizeof(int),
6650 		.mode		= 0644,
6651 		.proc_handler	= proc_dointvec,
6652 	},
6653 #endif
6654 #ifdef CONFIG_IPV6_MROUTE
6655 	{
6656 		.procname	= "mc_forwarding",
6657 		.data		= &ipv6_devconf.mc_forwarding,
6658 		.maxlen		= sizeof(int),
6659 		.mode		= 0444,
6660 		.proc_handler	= proc_dointvec,
6661 	},
6662 #endif
6663 	{
6664 		.procname	= "disable_ipv6",
6665 		.data		= &ipv6_devconf.disable_ipv6,
6666 		.maxlen		= sizeof(int),
6667 		.mode		= 0644,
6668 		.proc_handler	= addrconf_sysctl_disable,
6669 	},
6670 	{
6671 		.procname	= "accept_dad",
6672 		.data		= &ipv6_devconf.accept_dad,
6673 		.maxlen		= sizeof(int),
6674 		.mode		= 0644,
6675 		.proc_handler	= proc_dointvec,
6676 	},
6677 	{
6678 		.procname	= "force_tllao",
6679 		.data		= &ipv6_devconf.force_tllao,
6680 		.maxlen		= sizeof(int),
6681 		.mode		= 0644,
6682 		.proc_handler	= proc_dointvec
6683 	},
6684 	{
6685 		.procname	= "ndisc_notify",
6686 		.data		= &ipv6_devconf.ndisc_notify,
6687 		.maxlen		= sizeof(int),
6688 		.mode		= 0644,
6689 		.proc_handler	= proc_dointvec
6690 	},
6691 	{
6692 		.procname	= "suppress_frag_ndisc",
6693 		.data		= &ipv6_devconf.suppress_frag_ndisc,
6694 		.maxlen		= sizeof(int),
6695 		.mode		= 0644,
6696 		.proc_handler	= proc_dointvec
6697 	},
6698 	{
6699 		.procname	= "accept_ra_from_local",
6700 		.data		= &ipv6_devconf.accept_ra_from_local,
6701 		.maxlen		= sizeof(int),
6702 		.mode		= 0644,
6703 		.proc_handler	= proc_dointvec,
6704 	},
6705 	{
6706 		.procname	= "accept_ra_mtu",
6707 		.data		= &ipv6_devconf.accept_ra_mtu,
6708 		.maxlen		= sizeof(int),
6709 		.mode		= 0644,
6710 		.proc_handler	= proc_dointvec,
6711 	},
6712 	{
6713 		.procname	= "stable_secret",
6714 		.data		= &ipv6_devconf.stable_secret,
6715 		.maxlen		= IPV6_MAX_STRLEN,
6716 		.mode		= 0600,
6717 		.proc_handler	= addrconf_sysctl_stable_secret,
6718 	},
6719 	{
6720 		.procname	= "use_oif_addrs_only",
6721 		.data		= &ipv6_devconf.use_oif_addrs_only,
6722 		.maxlen		= sizeof(int),
6723 		.mode		= 0644,
6724 		.proc_handler	= proc_dointvec,
6725 	},
6726 	{
6727 		.procname	= "ignore_routes_with_linkdown",
6728 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
6729 		.maxlen		= sizeof(int),
6730 		.mode		= 0644,
6731 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
6732 	},
6733 	{
6734 		.procname	= "drop_unicast_in_l2_multicast",
6735 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
6736 		.maxlen		= sizeof(int),
6737 		.mode		= 0644,
6738 		.proc_handler	= proc_dointvec,
6739 	},
6740 	{
6741 		.procname	= "drop_unsolicited_na",
6742 		.data		= &ipv6_devconf.drop_unsolicited_na,
6743 		.maxlen		= sizeof(int),
6744 		.mode		= 0644,
6745 		.proc_handler	= proc_dointvec,
6746 	},
6747 	{
6748 		.procname	= "keep_addr_on_down",
6749 		.data		= &ipv6_devconf.keep_addr_on_down,
6750 		.maxlen		= sizeof(int),
6751 		.mode		= 0644,
6752 		.proc_handler	= proc_dointvec,
6753 
6754 	},
6755 	{
6756 		.procname	= "seg6_enabled",
6757 		.data		= &ipv6_devconf.seg6_enabled,
6758 		.maxlen		= sizeof(int),
6759 		.mode		= 0644,
6760 		.proc_handler	= proc_dointvec,
6761 	},
6762 #ifdef CONFIG_IPV6_SEG6_HMAC
6763 	{
6764 		.procname	= "seg6_require_hmac",
6765 		.data		= &ipv6_devconf.seg6_require_hmac,
6766 		.maxlen		= sizeof(int),
6767 		.mode		= 0644,
6768 		.proc_handler	= proc_dointvec,
6769 	},
6770 #endif
6771 	{
6772 		.procname       = "enhanced_dad",
6773 		.data           = &ipv6_devconf.enhanced_dad,
6774 		.maxlen         = sizeof(int),
6775 		.mode           = 0644,
6776 		.proc_handler   = proc_dointvec,
6777 	},
6778 	{
6779 		.procname		= "addr_gen_mode",
6780 		.data			= &ipv6_devconf.addr_gen_mode,
6781 		.maxlen			= sizeof(int),
6782 		.mode			= 0644,
6783 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
6784 	},
6785 	{
6786 		.procname       = "disable_policy",
6787 		.data           = &ipv6_devconf.disable_policy,
6788 		.maxlen         = sizeof(int),
6789 		.mode           = 0644,
6790 		.proc_handler   = addrconf_sysctl_disable_policy,
6791 	},
6792 	{
6793 		.procname	= "ndisc_tclass",
6794 		.data		= &ipv6_devconf.ndisc_tclass,
6795 		.maxlen		= sizeof(int),
6796 		.mode		= 0644,
6797 		.proc_handler	= proc_dointvec_minmax,
6798 		.extra1		= (void *)&zero,
6799 		.extra2		= (void *)&two_five_five,
6800 	},
6801 	{
6802 		/* sentinel */
6803 	}
6804 };
6805 
6806 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
6807 		struct inet6_dev *idev, struct ipv6_devconf *p)
6808 {
6809 	int i, ifindex;
6810 	struct ctl_table *table;
6811 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
6812 
6813 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL);
6814 	if (!table)
6815 		goto out;
6816 
6817 	for (i = 0; table[i].data; i++) {
6818 		table[i].data += (char *)p - (char *)&ipv6_devconf;
6819 		/* If one of these is already set, then it is not safe to
6820 		 * overwrite either of them: this makes proc_dointvec_minmax
6821 		 * usable.
6822 		 */
6823 		if (!table[i].extra1 && !table[i].extra2) {
6824 			table[i].extra1 = idev; /* embedded; no ref */
6825 			table[i].extra2 = net;
6826 		}
6827 	}
6828 
6829 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
6830 
6831 	p->sysctl_header = register_net_sysctl(net, path, table);
6832 	if (!p->sysctl_header)
6833 		goto free;
6834 
6835 	if (!strcmp(dev_name, "all"))
6836 		ifindex = NETCONFA_IFINDEX_ALL;
6837 	else if (!strcmp(dev_name, "default"))
6838 		ifindex = NETCONFA_IFINDEX_DEFAULT;
6839 	else
6840 		ifindex = idev->dev->ifindex;
6841 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
6842 				     ifindex, p);
6843 	return 0;
6844 
6845 free:
6846 	kfree(table);
6847 out:
6848 	return -ENOBUFS;
6849 }
6850 
6851 static void __addrconf_sysctl_unregister(struct net *net,
6852 					 struct ipv6_devconf *p, int ifindex)
6853 {
6854 	struct ctl_table *table;
6855 
6856 	if (!p->sysctl_header)
6857 		return;
6858 
6859 	table = p->sysctl_header->ctl_table_arg;
6860 	unregister_net_sysctl_table(p->sysctl_header);
6861 	p->sysctl_header = NULL;
6862 	kfree(table);
6863 
6864 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
6865 }
6866 
6867 static int addrconf_sysctl_register(struct inet6_dev *idev)
6868 {
6869 	int err;
6870 
6871 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
6872 		return -EINVAL;
6873 
6874 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
6875 				    &ndisc_ifinfo_sysctl_change);
6876 	if (err)
6877 		return err;
6878 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
6879 					 idev, &idev->cnf);
6880 	if (err)
6881 		neigh_sysctl_unregister(idev->nd_parms);
6882 
6883 	return err;
6884 }
6885 
6886 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
6887 {
6888 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
6889 				     idev->dev->ifindex);
6890 	neigh_sysctl_unregister(idev->nd_parms);
6891 }
6892 
6893 
6894 #endif
6895 
6896 static int __net_init addrconf_init_net(struct net *net)
6897 {
6898 	int err = -ENOMEM;
6899 	struct ipv6_devconf *all, *dflt;
6900 
6901 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
6902 	if (!all)
6903 		goto err_alloc_all;
6904 
6905 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
6906 	if (!dflt)
6907 		goto err_alloc_dflt;
6908 
6909 	if (IS_ENABLED(CONFIG_SYSCTL) &&
6910 	    sysctl_devconf_inherit_init_net == 1 && !net_eq(net, &init_net)) {
6911 		memcpy(all, init_net.ipv6.devconf_all, sizeof(ipv6_devconf));
6912 		memcpy(dflt, init_net.ipv6.devconf_dflt, sizeof(ipv6_devconf_dflt));
6913 	}
6914 
6915 	/* these will be inherited by all namespaces */
6916 	dflt->autoconf = ipv6_defaults.autoconf;
6917 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
6918 
6919 	dflt->stable_secret.initialized = false;
6920 	all->stable_secret.initialized = false;
6921 
6922 	net->ipv6.devconf_all = all;
6923 	net->ipv6.devconf_dflt = dflt;
6924 
6925 #ifdef CONFIG_SYSCTL
6926 	err = __addrconf_sysctl_register(net, "all", NULL, all);
6927 	if (err < 0)
6928 		goto err_reg_all;
6929 
6930 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
6931 	if (err < 0)
6932 		goto err_reg_dflt;
6933 #endif
6934 	return 0;
6935 
6936 #ifdef CONFIG_SYSCTL
6937 err_reg_dflt:
6938 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
6939 err_reg_all:
6940 	kfree(dflt);
6941 #endif
6942 err_alloc_dflt:
6943 	kfree(all);
6944 err_alloc_all:
6945 	return err;
6946 }
6947 
6948 static void __net_exit addrconf_exit_net(struct net *net)
6949 {
6950 #ifdef CONFIG_SYSCTL
6951 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
6952 				     NETCONFA_IFINDEX_DEFAULT);
6953 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
6954 				     NETCONFA_IFINDEX_ALL);
6955 #endif
6956 	kfree(net->ipv6.devconf_dflt);
6957 	kfree(net->ipv6.devconf_all);
6958 }
6959 
6960 static struct pernet_operations addrconf_ops = {
6961 	.init = addrconf_init_net,
6962 	.exit = addrconf_exit_net,
6963 };
6964 
6965 static struct rtnl_af_ops inet6_ops __read_mostly = {
6966 	.family		  = AF_INET6,
6967 	.fill_link_af	  = inet6_fill_link_af,
6968 	.get_link_af_size = inet6_get_link_af_size,
6969 	.validate_link_af = inet6_validate_link_af,
6970 	.set_link_af	  = inet6_set_link_af,
6971 };
6972 
6973 /*
6974  *	Init / cleanup code
6975  */
6976 
6977 int __init addrconf_init(void)
6978 {
6979 	struct inet6_dev *idev;
6980 	int i, err;
6981 
6982 	err = ipv6_addr_label_init();
6983 	if (err < 0) {
6984 		pr_crit("%s: cannot initialize default policy table: %d\n",
6985 			__func__, err);
6986 		goto out;
6987 	}
6988 
6989 	err = register_pernet_subsys(&addrconf_ops);
6990 	if (err < 0)
6991 		goto out_addrlabel;
6992 
6993 	addrconf_wq = create_workqueue("ipv6_addrconf");
6994 	if (!addrconf_wq) {
6995 		err = -ENOMEM;
6996 		goto out_nowq;
6997 	}
6998 
6999 	/* The addrconf netdev notifier requires that loopback_dev
7000 	 * has it's ipv6 private information allocated and setup
7001 	 * before it can bring up and give link-local addresses
7002 	 * to other devices which are up.
7003 	 *
7004 	 * Unfortunately, loopback_dev is not necessarily the first
7005 	 * entry in the global dev_base list of net devices.  In fact,
7006 	 * it is likely to be the very last entry on that list.
7007 	 * So this causes the notifier registry below to try and
7008 	 * give link-local addresses to all devices besides loopback_dev
7009 	 * first, then loopback_dev, which cases all the non-loopback_dev
7010 	 * devices to fail to get a link-local address.
7011 	 *
7012 	 * So, as a temporary fix, allocate the ipv6 structure for
7013 	 * loopback_dev first by hand.
7014 	 * Longer term, all of the dependencies ipv6 has upon the loopback
7015 	 * device and it being up should be removed.
7016 	 */
7017 	rtnl_lock();
7018 	idev = ipv6_add_dev(init_net.loopback_dev);
7019 	rtnl_unlock();
7020 	if (IS_ERR(idev)) {
7021 		err = PTR_ERR(idev);
7022 		goto errlo;
7023 	}
7024 
7025 	ip6_route_init_special_entries();
7026 
7027 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7028 		INIT_HLIST_HEAD(&inet6_addr_lst[i]);
7029 
7030 	register_netdevice_notifier(&ipv6_dev_notf);
7031 
7032 	addrconf_verify();
7033 
7034 	rtnl_af_register(&inet6_ops);
7035 
7036 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETLINK,
7037 				   NULL, inet6_dump_ifinfo, 0);
7038 	if (err < 0)
7039 		goto errout;
7040 
7041 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWADDR,
7042 				   inet6_rtm_newaddr, NULL, 0);
7043 	if (err < 0)
7044 		goto errout;
7045 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELADDR,
7046 				   inet6_rtm_deladdr, NULL, 0);
7047 	if (err < 0)
7048 		goto errout;
7049 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDR,
7050 				   inet6_rtm_getaddr, inet6_dump_ifaddr,
7051 				   RTNL_FLAG_DOIT_UNLOCKED);
7052 	if (err < 0)
7053 		goto errout;
7054 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETMULTICAST,
7055 				   NULL, inet6_dump_ifmcaddr, 0);
7056 	if (err < 0)
7057 		goto errout;
7058 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETANYCAST,
7059 				   NULL, inet6_dump_ifacaddr, 0);
7060 	if (err < 0)
7061 		goto errout;
7062 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETNETCONF,
7063 				   inet6_netconf_get_devconf,
7064 				   inet6_netconf_dump_devconf,
7065 				   RTNL_FLAG_DOIT_UNLOCKED);
7066 	if (err < 0)
7067 		goto errout;
7068 	err = ipv6_addr_label_rtnl_register();
7069 	if (err < 0)
7070 		goto errout;
7071 
7072 	return 0;
7073 errout:
7074 	rtnl_unregister_all(PF_INET6);
7075 	rtnl_af_unregister(&inet6_ops);
7076 	unregister_netdevice_notifier(&ipv6_dev_notf);
7077 errlo:
7078 	destroy_workqueue(addrconf_wq);
7079 out_nowq:
7080 	unregister_pernet_subsys(&addrconf_ops);
7081 out_addrlabel:
7082 	ipv6_addr_label_cleanup();
7083 out:
7084 	return err;
7085 }
7086 
7087 void addrconf_cleanup(void)
7088 {
7089 	struct net_device *dev;
7090 	int i;
7091 
7092 	unregister_netdevice_notifier(&ipv6_dev_notf);
7093 	unregister_pernet_subsys(&addrconf_ops);
7094 	ipv6_addr_label_cleanup();
7095 
7096 	rtnl_af_unregister(&inet6_ops);
7097 
7098 	rtnl_lock();
7099 
7100 	/* clean dev list */
7101 	for_each_netdev(&init_net, dev) {
7102 		if (__in6_dev_get(dev) == NULL)
7103 			continue;
7104 		addrconf_ifdown(dev, 1);
7105 	}
7106 	addrconf_ifdown(init_net.loopback_dev, 2);
7107 
7108 	/*
7109 	 *	Check hash table.
7110 	 */
7111 	spin_lock_bh(&addrconf_hash_lock);
7112 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7113 		WARN_ON(!hlist_empty(&inet6_addr_lst[i]));
7114 	spin_unlock_bh(&addrconf_hash_lock);
7115 	cancel_delayed_work(&addr_chk_work);
7116 	rtnl_unlock();
7117 
7118 	destroy_workqueue(addrconf_wq);
7119 }
7120