xref: /openbmc/linux/net/ipv6/addrconf.c (revision 5cd17f0e)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *	IPv6 Address [auto]configuration
4  *	Linux INET6 implementation
5  *
6  *	Authors:
7  *	Pedro Roque		<roque@di.fc.ul.pt>
8  *	Alexey Kuznetsov	<kuznet@ms2.inr.ac.ru>
9  */
10 
11 /*
12  *	Changes:
13  *
14  *	Janos Farkas			:	delete timer on ifdown
15  *	<chexum@bankinf.banki.hu>
16  *	Andi Kleen			:	kill double kfree on module
17  *						unload.
18  *	Maciej W. Rozycki		:	FDDI support
19  *	sekiya@USAGI			:	Don't send too many RS
20  *						packets.
21  *	yoshfuji@USAGI			:       Fixed interval between DAD
22  *						packets.
23  *	YOSHIFUJI Hideaki @USAGI	:	improved accuracy of
24  *						address validation timer.
25  *	YOSHIFUJI Hideaki @USAGI	:	Privacy Extensions (RFC3041)
26  *						support.
27  *	Yuji SEKIYA @USAGI		:	Don't assign a same IPv6
28  *						address on a same interface.
29  *	YOSHIFUJI Hideaki @USAGI	:	ARCnet support
30  *	YOSHIFUJI Hideaki @USAGI	:	convert /proc/net/if_inet6 to
31  *						seq_file.
32  *	YOSHIFUJI Hideaki @USAGI	:	improved source address
33  *						selection; consider scope,
34  *						status etc.
35  */
36 
37 #define pr_fmt(fmt) "IPv6: " fmt
38 
39 #include <linux/errno.h>
40 #include <linux/types.h>
41 #include <linux/kernel.h>
42 #include <linux/sched/signal.h>
43 #include <linux/socket.h>
44 #include <linux/sockios.h>
45 #include <linux/net.h>
46 #include <linux/inet.h>
47 #include <linux/in6.h>
48 #include <linux/netdevice.h>
49 #include <linux/if_addr.h>
50 #include <linux/if_arp.h>
51 #include <linux/if_arcnet.h>
52 #include <linux/if_infiniband.h>
53 #include <linux/route.h>
54 #include <linux/inetdevice.h>
55 #include <linux/init.h>
56 #include <linux/slab.h>
57 #ifdef CONFIG_SYSCTL
58 #include <linux/sysctl.h>
59 #endif
60 #include <linux/capability.h>
61 #include <linux/delay.h>
62 #include <linux/notifier.h>
63 #include <linux/string.h>
64 #include <linux/hash.h>
65 
66 #include <net/net_namespace.h>
67 #include <net/sock.h>
68 #include <net/snmp.h>
69 
70 #include <net/6lowpan.h>
71 #include <net/firewire.h>
72 #include <net/ipv6.h>
73 #include <net/protocol.h>
74 #include <net/ndisc.h>
75 #include <net/ip6_route.h>
76 #include <net/addrconf.h>
77 #include <net/tcp.h>
78 #include <net/ip.h>
79 #include <net/netlink.h>
80 #include <net/pkt_sched.h>
81 #include <net/l3mdev.h>
82 #include <linux/if_tunnel.h>
83 #include <linux/rtnetlink.h>
84 #include <linux/netconf.h>
85 #include <linux/random.h>
86 #include <linux/uaccess.h>
87 #include <asm/unaligned.h>
88 
89 #include <linux/proc_fs.h>
90 #include <linux/seq_file.h>
91 #include <linux/export.h>
92 #include <linux/ioam6.h>
93 
94 #define	INFINITY_LIFE_TIME	0xFFFFFFFF
95 
96 #define IPV6_MAX_STRLEN \
97 	sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")
98 
99 static inline u32 cstamp_delta(unsigned long cstamp)
100 {
101 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
102 }
103 
104 static inline s32 rfc3315_s14_backoff_init(s32 irt)
105 {
106 	/* multiply 'initial retransmission time' by 0.9 .. 1.1 */
107 	u64 tmp = get_random_u32_inclusive(900000, 1100000) * (u64)irt;
108 	do_div(tmp, 1000000);
109 	return (s32)tmp;
110 }
111 
112 static inline s32 rfc3315_s14_backoff_update(s32 rt, s32 mrt)
113 {
114 	/* multiply 'retransmission timeout' by 1.9 .. 2.1 */
115 	u64 tmp = get_random_u32_inclusive(1900000, 2100000) * (u64)rt;
116 	do_div(tmp, 1000000);
117 	if ((s32)tmp > mrt) {
118 		/* multiply 'maximum retransmission time' by 0.9 .. 1.1 */
119 		tmp = get_random_u32_inclusive(900000, 1100000) * (u64)mrt;
120 		do_div(tmp, 1000000);
121 	}
122 	return (s32)tmp;
123 }
124 
125 #ifdef CONFIG_SYSCTL
126 static int addrconf_sysctl_register(struct inet6_dev *idev);
127 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
128 #else
129 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
130 {
131 	return 0;
132 }
133 
134 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
135 {
136 }
137 #endif
138 
139 static void ipv6_gen_rnd_iid(struct in6_addr *addr);
140 
141 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
142 static int ipv6_count_addresses(const struct inet6_dev *idev);
143 static int ipv6_generate_stable_address(struct in6_addr *addr,
144 					u8 dad_count,
145 					const struct inet6_dev *idev);
146 
147 #define IN6_ADDR_HSIZE_SHIFT	8
148 #define IN6_ADDR_HSIZE		(1 << IN6_ADDR_HSIZE_SHIFT)
149 
150 static void addrconf_verify(struct net *net);
151 static void addrconf_verify_rtnl(struct net *net);
152 
153 static struct workqueue_struct *addrconf_wq;
154 
155 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
156 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
157 
158 static void addrconf_type_change(struct net_device *dev,
159 				 unsigned long event);
160 static int addrconf_ifdown(struct net_device *dev, bool unregister);
161 
162 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
163 						  int plen,
164 						  const struct net_device *dev,
165 						  u32 flags, u32 noflags,
166 						  bool no_gw);
167 
168 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
169 static void addrconf_dad_work(struct work_struct *w);
170 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
171 				   bool send_na);
172 static void addrconf_dad_run(struct inet6_dev *idev, bool restart);
173 static void addrconf_rs_timer(struct timer_list *t);
174 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
175 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
176 
177 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
178 				struct prefix_info *pinfo);
179 
180 static struct ipv6_devconf ipv6_devconf __read_mostly = {
181 	.forwarding		= 0,
182 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
183 	.mtu6			= IPV6_MIN_MTU,
184 	.accept_ra		= 1,
185 	.accept_redirects	= 1,
186 	.autoconf		= 1,
187 	.force_mld_version	= 0,
188 	.mldv1_unsolicited_report_interval = 10 * HZ,
189 	.mldv2_unsolicited_report_interval = HZ,
190 	.dad_transmits		= 1,
191 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
192 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
193 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
194 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
195 	.use_tempaddr		= 0,
196 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
197 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
198 	.regen_max_retry	= REGEN_MAX_RETRY,
199 	.max_desync_factor	= MAX_DESYNC_FACTOR,
200 	.max_addresses		= IPV6_MAX_ADDRESSES,
201 	.accept_ra_defrtr	= 1,
202 	.ra_defrtr_metric	= IP6_RT_PRIO_USER,
203 	.accept_ra_from_local	= 0,
204 	.accept_ra_min_hop_limit= 1,
205 	.accept_ra_min_lft	= 0,
206 	.accept_ra_pinfo	= 1,
207 #ifdef CONFIG_IPV6_ROUTER_PREF
208 	.accept_ra_rtr_pref	= 1,
209 	.rtr_probe_interval	= 60 * HZ,
210 #ifdef CONFIG_IPV6_ROUTE_INFO
211 	.accept_ra_rt_info_min_plen = 0,
212 	.accept_ra_rt_info_max_plen = 0,
213 #endif
214 #endif
215 	.proxy_ndp		= 0,
216 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
217 	.disable_ipv6		= 0,
218 	.accept_dad		= 0,
219 	.suppress_frag_ndisc	= 1,
220 	.accept_ra_mtu		= 1,
221 	.stable_secret		= {
222 		.initialized = false,
223 	},
224 	.use_oif_addrs_only	= 0,
225 	.ignore_routes_with_linkdown = 0,
226 	.keep_addr_on_down	= 0,
227 	.seg6_enabled		= 0,
228 #ifdef CONFIG_IPV6_SEG6_HMAC
229 	.seg6_require_hmac	= 0,
230 #endif
231 	.enhanced_dad           = 1,
232 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
233 	.disable_policy		= 0,
234 	.rpl_seg_enabled	= 0,
235 	.ioam6_enabled		= 0,
236 	.ioam6_id               = IOAM6_DEFAULT_IF_ID,
237 	.ioam6_id_wide		= IOAM6_DEFAULT_IF_ID_WIDE,
238 	.ndisc_evict_nocarrier	= 1,
239 };
240 
241 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
242 	.forwarding		= 0,
243 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
244 	.mtu6			= IPV6_MIN_MTU,
245 	.accept_ra		= 1,
246 	.accept_redirects	= 1,
247 	.autoconf		= 1,
248 	.force_mld_version	= 0,
249 	.mldv1_unsolicited_report_interval = 10 * HZ,
250 	.mldv2_unsolicited_report_interval = HZ,
251 	.dad_transmits		= 1,
252 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
253 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
254 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
255 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
256 	.use_tempaddr		= 0,
257 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
258 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
259 	.regen_max_retry	= REGEN_MAX_RETRY,
260 	.max_desync_factor	= MAX_DESYNC_FACTOR,
261 	.max_addresses		= IPV6_MAX_ADDRESSES,
262 	.accept_ra_defrtr	= 1,
263 	.ra_defrtr_metric	= IP6_RT_PRIO_USER,
264 	.accept_ra_from_local	= 0,
265 	.accept_ra_min_hop_limit= 1,
266 	.accept_ra_min_lft	= 0,
267 	.accept_ra_pinfo	= 1,
268 #ifdef CONFIG_IPV6_ROUTER_PREF
269 	.accept_ra_rtr_pref	= 1,
270 	.rtr_probe_interval	= 60 * HZ,
271 #ifdef CONFIG_IPV6_ROUTE_INFO
272 	.accept_ra_rt_info_min_plen = 0,
273 	.accept_ra_rt_info_max_plen = 0,
274 #endif
275 #endif
276 	.proxy_ndp		= 0,
277 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
278 	.disable_ipv6		= 0,
279 	.accept_dad		= 1,
280 	.suppress_frag_ndisc	= 1,
281 	.accept_ra_mtu		= 1,
282 	.stable_secret		= {
283 		.initialized = false,
284 	},
285 	.use_oif_addrs_only	= 0,
286 	.ignore_routes_with_linkdown = 0,
287 	.keep_addr_on_down	= 0,
288 	.seg6_enabled		= 0,
289 #ifdef CONFIG_IPV6_SEG6_HMAC
290 	.seg6_require_hmac	= 0,
291 #endif
292 	.enhanced_dad           = 1,
293 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
294 	.disable_policy		= 0,
295 	.rpl_seg_enabled	= 0,
296 	.ioam6_enabled		= 0,
297 	.ioam6_id               = IOAM6_DEFAULT_IF_ID,
298 	.ioam6_id_wide		= IOAM6_DEFAULT_IF_ID_WIDE,
299 	.ndisc_evict_nocarrier	= 1,
300 };
301 
302 /* Check if link is ready: is it up and is a valid qdisc available */
303 static inline bool addrconf_link_ready(const struct net_device *dev)
304 {
305 	return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
306 }
307 
308 static void addrconf_del_rs_timer(struct inet6_dev *idev)
309 {
310 	if (del_timer(&idev->rs_timer))
311 		__in6_dev_put(idev);
312 }
313 
314 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
315 {
316 	if (cancel_delayed_work(&ifp->dad_work))
317 		__in6_ifa_put(ifp);
318 }
319 
320 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
321 				  unsigned long when)
322 {
323 	if (!mod_timer(&idev->rs_timer, jiffies + when))
324 		in6_dev_hold(idev);
325 }
326 
327 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
328 				   unsigned long delay)
329 {
330 	in6_ifa_hold(ifp);
331 	if (mod_delayed_work(addrconf_wq, &ifp->dad_work, delay))
332 		in6_ifa_put(ifp);
333 }
334 
335 static int snmp6_alloc_dev(struct inet6_dev *idev)
336 {
337 	int i;
338 
339 	idev->stats.ipv6 = alloc_percpu_gfp(struct ipstats_mib, GFP_KERNEL_ACCOUNT);
340 	if (!idev->stats.ipv6)
341 		goto err_ip;
342 
343 	for_each_possible_cpu(i) {
344 		struct ipstats_mib *addrconf_stats;
345 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
346 		u64_stats_init(&addrconf_stats->syncp);
347 	}
348 
349 
350 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
351 					GFP_KERNEL);
352 	if (!idev->stats.icmpv6dev)
353 		goto err_icmp;
354 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
355 					   GFP_KERNEL_ACCOUNT);
356 	if (!idev->stats.icmpv6msgdev)
357 		goto err_icmpmsg;
358 
359 	return 0;
360 
361 err_icmpmsg:
362 	kfree(idev->stats.icmpv6dev);
363 err_icmp:
364 	free_percpu(idev->stats.ipv6);
365 err_ip:
366 	return -ENOMEM;
367 }
368 
369 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
370 {
371 	struct inet6_dev *ndev;
372 	int err = -ENOMEM;
373 
374 	ASSERT_RTNL();
375 
376 	if (dev->mtu < IPV6_MIN_MTU && dev != blackhole_netdev)
377 		return ERR_PTR(-EINVAL);
378 
379 	ndev = kzalloc(sizeof(*ndev), GFP_KERNEL_ACCOUNT);
380 	if (!ndev)
381 		return ERR_PTR(err);
382 
383 	rwlock_init(&ndev->lock);
384 	ndev->dev = dev;
385 	INIT_LIST_HEAD(&ndev->addr_list);
386 	timer_setup(&ndev->rs_timer, addrconf_rs_timer, 0);
387 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
388 
389 	if (ndev->cnf.stable_secret.initialized)
390 		ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
391 
392 	ndev->cnf.mtu6 = dev->mtu;
393 	ndev->ra_mtu = 0;
394 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
395 	if (!ndev->nd_parms) {
396 		kfree(ndev);
397 		return ERR_PTR(err);
398 	}
399 	if (ndev->cnf.forwarding)
400 		dev_disable_lro(dev);
401 	/* We refer to the device */
402 	netdev_hold(dev, &ndev->dev_tracker, GFP_KERNEL);
403 
404 	if (snmp6_alloc_dev(ndev) < 0) {
405 		netdev_dbg(dev, "%s: cannot allocate memory for statistics\n",
406 			   __func__);
407 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
408 		netdev_put(dev, &ndev->dev_tracker);
409 		kfree(ndev);
410 		return ERR_PTR(err);
411 	}
412 
413 	if (dev != blackhole_netdev) {
414 		if (snmp6_register_dev(ndev) < 0) {
415 			netdev_dbg(dev, "%s: cannot create /proc/net/dev_snmp6/%s\n",
416 				   __func__, dev->name);
417 			goto err_release;
418 		}
419 	}
420 	/* One reference from device. */
421 	refcount_set(&ndev->refcnt, 1);
422 
423 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
424 		ndev->cnf.accept_dad = -1;
425 
426 #if IS_ENABLED(CONFIG_IPV6_SIT)
427 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
428 		pr_info("%s: Disabled Multicast RS\n", dev->name);
429 		ndev->cnf.rtr_solicits = 0;
430 	}
431 #endif
432 
433 	INIT_LIST_HEAD(&ndev->tempaddr_list);
434 	ndev->desync_factor = U32_MAX;
435 	if ((dev->flags&IFF_LOOPBACK) ||
436 	    dev->type == ARPHRD_TUNNEL ||
437 	    dev->type == ARPHRD_TUNNEL6 ||
438 	    dev->type == ARPHRD_SIT ||
439 	    dev->type == ARPHRD_NONE) {
440 		ndev->cnf.use_tempaddr = -1;
441 	}
442 
443 	ndev->token = in6addr_any;
444 
445 	if (netif_running(dev) && addrconf_link_ready(dev))
446 		ndev->if_flags |= IF_READY;
447 
448 	ipv6_mc_init_dev(ndev);
449 	ndev->tstamp = jiffies;
450 	if (dev != blackhole_netdev) {
451 		err = addrconf_sysctl_register(ndev);
452 		if (err) {
453 			ipv6_mc_destroy_dev(ndev);
454 			snmp6_unregister_dev(ndev);
455 			goto err_release;
456 		}
457 	}
458 	/* protected by rtnl_lock */
459 	rcu_assign_pointer(dev->ip6_ptr, ndev);
460 
461 	if (dev != blackhole_netdev) {
462 		/* Join interface-local all-node multicast group */
463 		ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
464 
465 		/* Join all-node multicast group */
466 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
467 
468 		/* Join all-router multicast group if forwarding is set */
469 		if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
470 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
471 	}
472 	return ndev;
473 
474 err_release:
475 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
476 	ndev->dead = 1;
477 	in6_dev_finish_destroy(ndev);
478 	return ERR_PTR(err);
479 }
480 
481 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
482 {
483 	struct inet6_dev *idev;
484 
485 	ASSERT_RTNL();
486 
487 	idev = __in6_dev_get(dev);
488 	if (!idev) {
489 		idev = ipv6_add_dev(dev);
490 		if (IS_ERR(idev))
491 			return idev;
492 	}
493 
494 	if (dev->flags&IFF_UP)
495 		ipv6_mc_up(idev);
496 	return idev;
497 }
498 
499 static int inet6_netconf_msgsize_devconf(int type)
500 {
501 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
502 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
503 	bool all = false;
504 
505 	if (type == NETCONFA_ALL)
506 		all = true;
507 
508 	if (all || type == NETCONFA_FORWARDING)
509 		size += nla_total_size(4);
510 #ifdef CONFIG_IPV6_MROUTE
511 	if (all || type == NETCONFA_MC_FORWARDING)
512 		size += nla_total_size(4);
513 #endif
514 	if (all || type == NETCONFA_PROXY_NEIGH)
515 		size += nla_total_size(4);
516 
517 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
518 		size += nla_total_size(4);
519 
520 	return size;
521 }
522 
523 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
524 				      struct ipv6_devconf *devconf, u32 portid,
525 				      u32 seq, int event, unsigned int flags,
526 				      int type)
527 {
528 	struct nlmsghdr  *nlh;
529 	struct netconfmsg *ncm;
530 	bool all = false;
531 
532 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
533 			flags);
534 	if (!nlh)
535 		return -EMSGSIZE;
536 
537 	if (type == NETCONFA_ALL)
538 		all = true;
539 
540 	ncm = nlmsg_data(nlh);
541 	ncm->ncm_family = AF_INET6;
542 
543 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
544 		goto nla_put_failure;
545 
546 	if (!devconf)
547 		goto out;
548 
549 	if ((all || type == NETCONFA_FORWARDING) &&
550 	    nla_put_s32(skb, NETCONFA_FORWARDING, devconf->forwarding) < 0)
551 		goto nla_put_failure;
552 #ifdef CONFIG_IPV6_MROUTE
553 	if ((all || type == NETCONFA_MC_FORWARDING) &&
554 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
555 			atomic_read(&devconf->mc_forwarding)) < 0)
556 		goto nla_put_failure;
557 #endif
558 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
559 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH, devconf->proxy_ndp) < 0)
560 		goto nla_put_failure;
561 
562 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
563 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
564 			devconf->ignore_routes_with_linkdown) < 0)
565 		goto nla_put_failure;
566 
567 out:
568 	nlmsg_end(skb, nlh);
569 	return 0;
570 
571 nla_put_failure:
572 	nlmsg_cancel(skb, nlh);
573 	return -EMSGSIZE;
574 }
575 
576 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
577 				  int ifindex, struct ipv6_devconf *devconf)
578 {
579 	struct sk_buff *skb;
580 	int err = -ENOBUFS;
581 
582 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
583 	if (!skb)
584 		goto errout;
585 
586 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
587 					 event, 0, type);
588 	if (err < 0) {
589 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
590 		WARN_ON(err == -EMSGSIZE);
591 		kfree_skb(skb);
592 		goto errout;
593 	}
594 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
595 	return;
596 errout:
597 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
598 }
599 
600 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
601 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
602 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
603 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
604 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
605 };
606 
607 static int inet6_netconf_valid_get_req(struct sk_buff *skb,
608 				       const struct nlmsghdr *nlh,
609 				       struct nlattr **tb,
610 				       struct netlink_ext_ack *extack)
611 {
612 	int i, err;
613 
614 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(struct netconfmsg))) {
615 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf get request");
616 		return -EINVAL;
617 	}
618 
619 	if (!netlink_strict_get_check(skb))
620 		return nlmsg_parse_deprecated(nlh, sizeof(struct netconfmsg),
621 					      tb, NETCONFA_MAX,
622 					      devconf_ipv6_policy, extack);
623 
624 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct netconfmsg),
625 					    tb, NETCONFA_MAX,
626 					    devconf_ipv6_policy, extack);
627 	if (err)
628 		return err;
629 
630 	for (i = 0; i <= NETCONFA_MAX; i++) {
631 		if (!tb[i])
632 			continue;
633 
634 		switch (i) {
635 		case NETCONFA_IFINDEX:
636 			break;
637 		default:
638 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in netconf get request");
639 			return -EINVAL;
640 		}
641 	}
642 
643 	return 0;
644 }
645 
646 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
647 				     struct nlmsghdr *nlh,
648 				     struct netlink_ext_ack *extack)
649 {
650 	struct net *net = sock_net(in_skb->sk);
651 	struct nlattr *tb[NETCONFA_MAX+1];
652 	struct inet6_dev *in6_dev = NULL;
653 	struct net_device *dev = NULL;
654 	struct sk_buff *skb;
655 	struct ipv6_devconf *devconf;
656 	int ifindex;
657 	int err;
658 
659 	err = inet6_netconf_valid_get_req(in_skb, nlh, tb, extack);
660 	if (err < 0)
661 		return err;
662 
663 	if (!tb[NETCONFA_IFINDEX])
664 		return -EINVAL;
665 
666 	err = -EINVAL;
667 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
668 	switch (ifindex) {
669 	case NETCONFA_IFINDEX_ALL:
670 		devconf = net->ipv6.devconf_all;
671 		break;
672 	case NETCONFA_IFINDEX_DEFAULT:
673 		devconf = net->ipv6.devconf_dflt;
674 		break;
675 	default:
676 		dev = dev_get_by_index(net, ifindex);
677 		if (!dev)
678 			return -EINVAL;
679 		in6_dev = in6_dev_get(dev);
680 		if (!in6_dev)
681 			goto errout;
682 		devconf = &in6_dev->cnf;
683 		break;
684 	}
685 
686 	err = -ENOBUFS;
687 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
688 	if (!skb)
689 		goto errout;
690 
691 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
692 					 NETLINK_CB(in_skb).portid,
693 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
694 					 NETCONFA_ALL);
695 	if (err < 0) {
696 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
697 		WARN_ON(err == -EMSGSIZE);
698 		kfree_skb(skb);
699 		goto errout;
700 	}
701 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
702 errout:
703 	if (in6_dev)
704 		in6_dev_put(in6_dev);
705 	dev_put(dev);
706 	return err;
707 }
708 
709 /* Combine dev_addr_genid and dev_base_seq to detect changes.
710  */
711 static u32 inet6_base_seq(const struct net *net)
712 {
713 	u32 res = atomic_read(&net->ipv6.dev_addr_genid) +
714 		  net->dev_base_seq;
715 
716 	/* Must not return 0 (see nl_dump_check_consistent()).
717 	 * Chose a value far away from 0.
718 	 */
719 	if (!res)
720 		res = 0x80000000;
721 	return res;
722 }
723 
724 
725 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
726 				      struct netlink_callback *cb)
727 {
728 	const struct nlmsghdr *nlh = cb->nlh;
729 	struct net *net = sock_net(skb->sk);
730 	int h, s_h;
731 	int idx, s_idx;
732 	struct net_device *dev;
733 	struct inet6_dev *idev;
734 	struct hlist_head *head;
735 
736 	if (cb->strict_check) {
737 		struct netlink_ext_ack *extack = cb->extack;
738 		struct netconfmsg *ncm;
739 
740 		if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) {
741 			NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf dump request");
742 			return -EINVAL;
743 		}
744 
745 		if (nlmsg_attrlen(nlh, sizeof(*ncm))) {
746 			NL_SET_ERR_MSG_MOD(extack, "Invalid data after header in netconf dump request");
747 			return -EINVAL;
748 		}
749 	}
750 
751 	s_h = cb->args[0];
752 	s_idx = idx = cb->args[1];
753 
754 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
755 		idx = 0;
756 		head = &net->dev_index_head[h];
757 		rcu_read_lock();
758 		cb->seq = inet6_base_seq(net);
759 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
760 			if (idx < s_idx)
761 				goto cont;
762 			idev = __in6_dev_get(dev);
763 			if (!idev)
764 				goto cont;
765 
766 			if (inet6_netconf_fill_devconf(skb, dev->ifindex,
767 						       &idev->cnf,
768 						       NETLINK_CB(cb->skb).portid,
769 						       nlh->nlmsg_seq,
770 						       RTM_NEWNETCONF,
771 						       NLM_F_MULTI,
772 						       NETCONFA_ALL) < 0) {
773 				rcu_read_unlock();
774 				goto done;
775 			}
776 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
777 cont:
778 			idx++;
779 		}
780 		rcu_read_unlock();
781 	}
782 	if (h == NETDEV_HASHENTRIES) {
783 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
784 					       net->ipv6.devconf_all,
785 					       NETLINK_CB(cb->skb).portid,
786 					       nlh->nlmsg_seq,
787 					       RTM_NEWNETCONF, NLM_F_MULTI,
788 					       NETCONFA_ALL) < 0)
789 			goto done;
790 		else
791 			h++;
792 	}
793 	if (h == NETDEV_HASHENTRIES + 1) {
794 		if (inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
795 					       net->ipv6.devconf_dflt,
796 					       NETLINK_CB(cb->skb).portid,
797 					       nlh->nlmsg_seq,
798 					       RTM_NEWNETCONF, NLM_F_MULTI,
799 					       NETCONFA_ALL) < 0)
800 			goto done;
801 		else
802 			h++;
803 	}
804 done:
805 	cb->args[0] = h;
806 	cb->args[1] = idx;
807 
808 	return skb->len;
809 }
810 
811 #ifdef CONFIG_SYSCTL
812 static void dev_forward_change(struct inet6_dev *idev)
813 {
814 	struct net_device *dev;
815 	struct inet6_ifaddr *ifa;
816 	LIST_HEAD(tmp_addr_list);
817 
818 	if (!idev)
819 		return;
820 	dev = idev->dev;
821 	if (idev->cnf.forwarding)
822 		dev_disable_lro(dev);
823 	if (dev->flags & IFF_MULTICAST) {
824 		if (idev->cnf.forwarding) {
825 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
826 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
827 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
828 		} else {
829 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
830 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
831 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
832 		}
833 	}
834 
835 	read_lock_bh(&idev->lock);
836 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
837 		if (ifa->flags&IFA_F_TENTATIVE)
838 			continue;
839 		list_add_tail(&ifa->if_list_aux, &tmp_addr_list);
840 	}
841 	read_unlock_bh(&idev->lock);
842 
843 	while (!list_empty(&tmp_addr_list)) {
844 		ifa = list_first_entry(&tmp_addr_list,
845 				       struct inet6_ifaddr, if_list_aux);
846 		list_del(&ifa->if_list_aux);
847 		if (idev->cnf.forwarding)
848 			addrconf_join_anycast(ifa);
849 		else
850 			addrconf_leave_anycast(ifa);
851 	}
852 
853 	inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
854 				     NETCONFA_FORWARDING,
855 				     dev->ifindex, &idev->cnf);
856 }
857 
858 
859 static void addrconf_forward_change(struct net *net, __s32 newf)
860 {
861 	struct net_device *dev;
862 	struct inet6_dev *idev;
863 
864 	for_each_netdev(net, dev) {
865 		idev = __in6_dev_get(dev);
866 		if (idev) {
867 			int changed = (!idev->cnf.forwarding) ^ (!newf);
868 			idev->cnf.forwarding = newf;
869 			if (changed)
870 				dev_forward_change(idev);
871 		}
872 	}
873 }
874 
875 static int addrconf_fixup_forwarding(struct ctl_table *table, int *p, int newf)
876 {
877 	struct net *net;
878 	int old;
879 
880 	if (!rtnl_trylock())
881 		return restart_syscall();
882 
883 	net = (struct net *)table->extra2;
884 	old = *p;
885 	*p = newf;
886 
887 	if (p == &net->ipv6.devconf_dflt->forwarding) {
888 		if ((!newf) ^ (!old))
889 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
890 						     NETCONFA_FORWARDING,
891 						     NETCONFA_IFINDEX_DEFAULT,
892 						     net->ipv6.devconf_dflt);
893 		rtnl_unlock();
894 		return 0;
895 	}
896 
897 	if (p == &net->ipv6.devconf_all->forwarding) {
898 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
899 
900 		net->ipv6.devconf_dflt->forwarding = newf;
901 		if ((!newf) ^ (!old_dflt))
902 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
903 						     NETCONFA_FORWARDING,
904 						     NETCONFA_IFINDEX_DEFAULT,
905 						     net->ipv6.devconf_dflt);
906 
907 		addrconf_forward_change(net, newf);
908 		if ((!newf) ^ (!old))
909 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
910 						     NETCONFA_FORWARDING,
911 						     NETCONFA_IFINDEX_ALL,
912 						     net->ipv6.devconf_all);
913 	} else if ((!newf) ^ (!old))
914 		dev_forward_change((struct inet6_dev *)table->extra1);
915 	rtnl_unlock();
916 
917 	if (newf)
918 		rt6_purge_dflt_routers(net);
919 	return 1;
920 }
921 
922 static void addrconf_linkdown_change(struct net *net, __s32 newf)
923 {
924 	struct net_device *dev;
925 	struct inet6_dev *idev;
926 
927 	for_each_netdev(net, dev) {
928 		idev = __in6_dev_get(dev);
929 		if (idev) {
930 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
931 
932 			idev->cnf.ignore_routes_with_linkdown = newf;
933 			if (changed)
934 				inet6_netconf_notify_devconf(dev_net(dev),
935 							     RTM_NEWNETCONF,
936 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
937 							     dev->ifindex,
938 							     &idev->cnf);
939 		}
940 	}
941 }
942 
943 static int addrconf_fixup_linkdown(struct ctl_table *table, int *p, int newf)
944 {
945 	struct net *net;
946 	int old;
947 
948 	if (!rtnl_trylock())
949 		return restart_syscall();
950 
951 	net = (struct net *)table->extra2;
952 	old = *p;
953 	*p = newf;
954 
955 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
956 		if ((!newf) ^ (!old))
957 			inet6_netconf_notify_devconf(net,
958 						     RTM_NEWNETCONF,
959 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
960 						     NETCONFA_IFINDEX_DEFAULT,
961 						     net->ipv6.devconf_dflt);
962 		rtnl_unlock();
963 		return 0;
964 	}
965 
966 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
967 		net->ipv6.devconf_dflt->ignore_routes_with_linkdown = newf;
968 		addrconf_linkdown_change(net, newf);
969 		if ((!newf) ^ (!old))
970 			inet6_netconf_notify_devconf(net,
971 						     RTM_NEWNETCONF,
972 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
973 						     NETCONFA_IFINDEX_ALL,
974 						     net->ipv6.devconf_all);
975 	}
976 	rtnl_unlock();
977 
978 	return 1;
979 }
980 
981 #endif
982 
983 /* Nobody refers to this ifaddr, destroy it */
984 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
985 {
986 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
987 
988 #ifdef NET_REFCNT_DEBUG
989 	pr_debug("%s\n", __func__);
990 #endif
991 
992 	in6_dev_put(ifp->idev);
993 
994 	if (cancel_delayed_work(&ifp->dad_work))
995 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
996 			  ifp);
997 
998 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
999 		pr_warn("Freeing alive inet6 address %p\n", ifp);
1000 		return;
1001 	}
1002 
1003 	kfree_rcu(ifp, rcu);
1004 }
1005 
1006 static void
1007 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
1008 {
1009 	struct list_head *p;
1010 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
1011 
1012 	/*
1013 	 * Each device address list is sorted in order of scope -
1014 	 * global before linklocal.
1015 	 */
1016 	list_for_each(p, &idev->addr_list) {
1017 		struct inet6_ifaddr *ifa
1018 			= list_entry(p, struct inet6_ifaddr, if_list);
1019 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
1020 			break;
1021 	}
1022 
1023 	list_add_tail_rcu(&ifp->if_list, p);
1024 }
1025 
1026 static u32 inet6_addr_hash(const struct net *net, const struct in6_addr *addr)
1027 {
1028 	u32 val = ipv6_addr_hash(addr) ^ net_hash_mix(net);
1029 
1030 	return hash_32(val, IN6_ADDR_HSIZE_SHIFT);
1031 }
1032 
1033 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1034 			       struct net_device *dev, unsigned int hash)
1035 {
1036 	struct inet6_ifaddr *ifp;
1037 
1038 	hlist_for_each_entry(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
1039 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1040 			if (!dev || ifp->idev->dev == dev)
1041 				return true;
1042 		}
1043 	}
1044 	return false;
1045 }
1046 
1047 static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
1048 {
1049 	struct net *net = dev_net(dev);
1050 	unsigned int hash = inet6_addr_hash(net, &ifa->addr);
1051 	int err = 0;
1052 
1053 	spin_lock_bh(&net->ipv6.addrconf_hash_lock);
1054 
1055 	/* Ignore adding duplicate addresses on an interface */
1056 	if (ipv6_chk_same_addr(net, &ifa->addr, dev, hash)) {
1057 		netdev_dbg(dev, "ipv6_add_addr: already assigned\n");
1058 		err = -EEXIST;
1059 	} else {
1060 		hlist_add_head_rcu(&ifa->addr_lst, &net->ipv6.inet6_addr_lst[hash]);
1061 	}
1062 
1063 	spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
1064 
1065 	return err;
1066 }
1067 
1068 /* On success it returns ifp with increased reference count */
1069 
1070 static struct inet6_ifaddr *
1071 ipv6_add_addr(struct inet6_dev *idev, struct ifa6_config *cfg,
1072 	      bool can_block, struct netlink_ext_ack *extack)
1073 {
1074 	gfp_t gfp_flags = can_block ? GFP_KERNEL : GFP_ATOMIC;
1075 	int addr_type = ipv6_addr_type(cfg->pfx);
1076 	struct net *net = dev_net(idev->dev);
1077 	struct inet6_ifaddr *ifa = NULL;
1078 	struct fib6_info *f6i = NULL;
1079 	int err = 0;
1080 
1081 	if (addr_type == IPV6_ADDR_ANY) {
1082 		NL_SET_ERR_MSG_MOD(extack, "Invalid address");
1083 		return ERR_PTR(-EADDRNOTAVAIL);
1084 	} else if (addr_type & IPV6_ADDR_MULTICAST &&
1085 		   !(cfg->ifa_flags & IFA_F_MCAUTOJOIN)) {
1086 		NL_SET_ERR_MSG_MOD(extack, "Cannot assign multicast address without \"IFA_F_MCAUTOJOIN\" flag");
1087 		return ERR_PTR(-EADDRNOTAVAIL);
1088 	} else if (!(idev->dev->flags & IFF_LOOPBACK) &&
1089 		   !netif_is_l3_master(idev->dev) &&
1090 		   addr_type & IPV6_ADDR_LOOPBACK) {
1091 		NL_SET_ERR_MSG_MOD(extack, "Cannot assign loopback address on this device");
1092 		return ERR_PTR(-EADDRNOTAVAIL);
1093 	}
1094 
1095 	if (idev->dead) {
1096 		NL_SET_ERR_MSG_MOD(extack, "device is going away");
1097 		err = -ENODEV;
1098 		goto out;
1099 	}
1100 
1101 	if (idev->cnf.disable_ipv6) {
1102 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
1103 		err = -EACCES;
1104 		goto out;
1105 	}
1106 
1107 	/* validator notifier needs to be blocking;
1108 	 * do not call in atomic context
1109 	 */
1110 	if (can_block) {
1111 		struct in6_validator_info i6vi = {
1112 			.i6vi_addr = *cfg->pfx,
1113 			.i6vi_dev = idev,
1114 			.extack = extack,
1115 		};
1116 
1117 		err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
1118 		err = notifier_to_errno(err);
1119 		if (err < 0)
1120 			goto out;
1121 	}
1122 
1123 	ifa = kzalloc(sizeof(*ifa), gfp_flags | __GFP_ACCOUNT);
1124 	if (!ifa) {
1125 		err = -ENOBUFS;
1126 		goto out;
1127 	}
1128 
1129 	f6i = addrconf_f6i_alloc(net, idev, cfg->pfx, false, gfp_flags, extack);
1130 	if (IS_ERR(f6i)) {
1131 		err = PTR_ERR(f6i);
1132 		f6i = NULL;
1133 		goto out;
1134 	}
1135 
1136 	neigh_parms_data_state_setall(idev->nd_parms);
1137 
1138 	ifa->addr = *cfg->pfx;
1139 	if (cfg->peer_pfx)
1140 		ifa->peer_addr = *cfg->peer_pfx;
1141 
1142 	spin_lock_init(&ifa->lock);
1143 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1144 	INIT_HLIST_NODE(&ifa->addr_lst);
1145 	ifa->scope = cfg->scope;
1146 	ifa->prefix_len = cfg->plen;
1147 	ifa->rt_priority = cfg->rt_priority;
1148 	ifa->flags = cfg->ifa_flags;
1149 	ifa->ifa_proto = cfg->ifa_proto;
1150 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1151 	if (!(cfg->ifa_flags & IFA_F_NODAD))
1152 		ifa->flags |= IFA_F_TENTATIVE;
1153 	ifa->valid_lft = cfg->valid_lft;
1154 	ifa->prefered_lft = cfg->preferred_lft;
1155 	ifa->cstamp = ifa->tstamp = jiffies;
1156 	ifa->tokenized = false;
1157 
1158 	ifa->rt = f6i;
1159 
1160 	ifa->idev = idev;
1161 	in6_dev_hold(idev);
1162 
1163 	/* For caller */
1164 	refcount_set(&ifa->refcnt, 1);
1165 
1166 	rcu_read_lock();
1167 
1168 	err = ipv6_add_addr_hash(idev->dev, ifa);
1169 	if (err < 0) {
1170 		rcu_read_unlock();
1171 		goto out;
1172 	}
1173 
1174 	write_lock_bh(&idev->lock);
1175 
1176 	/* Add to inet6_dev unicast addr list. */
1177 	ipv6_link_dev_addr(idev, ifa);
1178 
1179 	if (ifa->flags&IFA_F_TEMPORARY) {
1180 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1181 		in6_ifa_hold(ifa);
1182 	}
1183 
1184 	in6_ifa_hold(ifa);
1185 	write_unlock_bh(&idev->lock);
1186 
1187 	rcu_read_unlock();
1188 
1189 	inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1190 out:
1191 	if (unlikely(err < 0)) {
1192 		fib6_info_release(f6i);
1193 
1194 		if (ifa) {
1195 			if (ifa->idev)
1196 				in6_dev_put(ifa->idev);
1197 			kfree(ifa);
1198 		}
1199 		ifa = ERR_PTR(err);
1200 	}
1201 
1202 	return ifa;
1203 }
1204 
1205 enum cleanup_prefix_rt_t {
1206 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1207 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1208 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1209 };
1210 
1211 /*
1212  * Check, whether the prefix for ifp would still need a prefix route
1213  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1214  * constants.
1215  *
1216  * 1) we don't purge prefix if address was not permanent.
1217  *    prefix is managed by its own lifetime.
1218  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1219  * 3) if there are no addresses, delete prefix.
1220  * 4) if there are still other permanent address(es),
1221  *    corresponding prefix is still permanent.
1222  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1223  *    don't purge the prefix, assume user space is managing it.
1224  * 6) otherwise, update prefix lifetime to the
1225  *    longest valid lifetime among the corresponding
1226  *    addresses on the device.
1227  *    Note: subsequent RA will update lifetime.
1228  **/
1229 static enum cleanup_prefix_rt_t
1230 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1231 {
1232 	struct inet6_ifaddr *ifa;
1233 	struct inet6_dev *idev = ifp->idev;
1234 	unsigned long lifetime;
1235 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1236 
1237 	*expires = jiffies;
1238 
1239 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1240 		if (ifa == ifp)
1241 			continue;
1242 		if (ifa->prefix_len != ifp->prefix_len ||
1243 		    !ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1244 				       ifp->prefix_len))
1245 			continue;
1246 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1247 			return CLEANUP_PREFIX_RT_NOP;
1248 
1249 		action = CLEANUP_PREFIX_RT_EXPIRE;
1250 
1251 		spin_lock(&ifa->lock);
1252 
1253 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1254 		/*
1255 		 * Note: Because this address is
1256 		 * not permanent, lifetime <
1257 		 * LONG_MAX / HZ here.
1258 		 */
1259 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1260 			*expires = ifa->tstamp + lifetime * HZ;
1261 		spin_unlock(&ifa->lock);
1262 	}
1263 
1264 	return action;
1265 }
1266 
1267 static void
1268 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires,
1269 		     bool del_rt, bool del_peer)
1270 {
1271 	struct fib6_info *f6i;
1272 
1273 	f6i = addrconf_get_prefix_route(del_peer ? &ifp->peer_addr : &ifp->addr,
1274 					ifp->prefix_len,
1275 					ifp->idev->dev, 0, RTF_DEFAULT, true);
1276 	if (f6i) {
1277 		if (del_rt)
1278 			ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
1279 		else {
1280 			if (!(f6i->fib6_flags & RTF_EXPIRES))
1281 				fib6_set_expires(f6i, expires);
1282 			fib6_info_release(f6i);
1283 		}
1284 	}
1285 }
1286 
1287 
1288 /* This function wants to get referenced ifp and releases it before return */
1289 
1290 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1291 {
1292 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1293 	struct net *net = dev_net(ifp->idev->dev);
1294 	unsigned long expires;
1295 	int state;
1296 
1297 	ASSERT_RTNL();
1298 
1299 	spin_lock_bh(&ifp->lock);
1300 	state = ifp->state;
1301 	ifp->state = INET6_IFADDR_STATE_DEAD;
1302 	spin_unlock_bh(&ifp->lock);
1303 
1304 	if (state == INET6_IFADDR_STATE_DEAD)
1305 		goto out;
1306 
1307 	spin_lock_bh(&net->ipv6.addrconf_hash_lock);
1308 	hlist_del_init_rcu(&ifp->addr_lst);
1309 	spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
1310 
1311 	write_lock_bh(&ifp->idev->lock);
1312 
1313 	if (ifp->flags&IFA_F_TEMPORARY) {
1314 		list_del(&ifp->tmp_list);
1315 		if (ifp->ifpub) {
1316 			in6_ifa_put(ifp->ifpub);
1317 			ifp->ifpub = NULL;
1318 		}
1319 		__in6_ifa_put(ifp);
1320 	}
1321 
1322 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1323 		action = check_cleanup_prefix_route(ifp, &expires);
1324 
1325 	list_del_rcu(&ifp->if_list);
1326 	__in6_ifa_put(ifp);
1327 
1328 	write_unlock_bh(&ifp->idev->lock);
1329 
1330 	addrconf_del_dad_work(ifp);
1331 
1332 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1333 
1334 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1335 
1336 	if (action != CLEANUP_PREFIX_RT_NOP) {
1337 		cleanup_prefix_route(ifp, expires,
1338 			action == CLEANUP_PREFIX_RT_DEL, false);
1339 	}
1340 
1341 	/* clean up prefsrc entries */
1342 	rt6_remove_prefsrc(ifp);
1343 out:
1344 	in6_ifa_put(ifp);
1345 }
1346 
1347 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, bool block)
1348 {
1349 	struct inet6_dev *idev = ifp->idev;
1350 	unsigned long tmp_tstamp, age;
1351 	unsigned long regen_advance;
1352 	unsigned long now = jiffies;
1353 	s32 cnf_temp_preferred_lft;
1354 	struct inet6_ifaddr *ift;
1355 	struct ifa6_config cfg;
1356 	long max_desync_factor;
1357 	struct in6_addr addr;
1358 	int ret = 0;
1359 
1360 	write_lock_bh(&idev->lock);
1361 
1362 retry:
1363 	in6_dev_hold(idev);
1364 	if (idev->cnf.use_tempaddr <= 0) {
1365 		write_unlock_bh(&idev->lock);
1366 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1367 		in6_dev_put(idev);
1368 		ret = -1;
1369 		goto out;
1370 	}
1371 	spin_lock_bh(&ifp->lock);
1372 	if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
1373 		idev->cnf.use_tempaddr = -1;	/*XXX*/
1374 		spin_unlock_bh(&ifp->lock);
1375 		write_unlock_bh(&idev->lock);
1376 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1377 			__func__);
1378 		in6_dev_put(idev);
1379 		ret = -1;
1380 		goto out;
1381 	}
1382 	in6_ifa_hold(ifp);
1383 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1384 	ipv6_gen_rnd_iid(&addr);
1385 
1386 	age = (now - ifp->tstamp) / HZ;
1387 
1388 	regen_advance = idev->cnf.regen_max_retry *
1389 			idev->cnf.dad_transmits *
1390 			max(NEIGH_VAR(idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
1391 
1392 	/* recalculate max_desync_factor each time and update
1393 	 * idev->desync_factor if it's larger
1394 	 */
1395 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1396 	max_desync_factor = min_t(long,
1397 				  idev->cnf.max_desync_factor,
1398 				  cnf_temp_preferred_lft - regen_advance);
1399 
1400 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1401 		if (max_desync_factor > 0) {
1402 			get_random_bytes(&idev->desync_factor,
1403 					 sizeof(idev->desync_factor));
1404 			idev->desync_factor %= max_desync_factor;
1405 		} else {
1406 			idev->desync_factor = 0;
1407 		}
1408 	}
1409 
1410 	memset(&cfg, 0, sizeof(cfg));
1411 	cfg.valid_lft = min_t(__u32, ifp->valid_lft,
1412 			      idev->cnf.temp_valid_lft + age);
1413 	cfg.preferred_lft = cnf_temp_preferred_lft + age - idev->desync_factor;
1414 	cfg.preferred_lft = min_t(__u32, ifp->prefered_lft, cfg.preferred_lft);
1415 
1416 	cfg.plen = ifp->prefix_len;
1417 	tmp_tstamp = ifp->tstamp;
1418 	spin_unlock_bh(&ifp->lock);
1419 
1420 	write_unlock_bh(&idev->lock);
1421 
1422 	/* A temporary address is created only if this calculated Preferred
1423 	 * Lifetime is greater than REGEN_ADVANCE time units.  In particular,
1424 	 * an implementation must not create a temporary address with a zero
1425 	 * Preferred Lifetime.
1426 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1427 	 * temporary addresses being generated.
1428 	 */
1429 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1430 	if (cfg.preferred_lft <= regen_advance + age) {
1431 		in6_ifa_put(ifp);
1432 		in6_dev_put(idev);
1433 		ret = -1;
1434 		goto out;
1435 	}
1436 
1437 	cfg.ifa_flags = IFA_F_TEMPORARY;
1438 	/* set in addrconf_prefix_rcv() */
1439 	if (ifp->flags & IFA_F_OPTIMISTIC)
1440 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
1441 
1442 	cfg.pfx = &addr;
1443 	cfg.scope = ipv6_addr_scope(cfg.pfx);
1444 
1445 	ift = ipv6_add_addr(idev, &cfg, block, NULL);
1446 	if (IS_ERR(ift)) {
1447 		in6_ifa_put(ifp);
1448 		in6_dev_put(idev);
1449 		pr_info("%s: retry temporary address regeneration\n", __func__);
1450 		write_lock_bh(&idev->lock);
1451 		goto retry;
1452 	}
1453 
1454 	spin_lock_bh(&ift->lock);
1455 	ift->ifpub = ifp;
1456 	ift->cstamp = now;
1457 	ift->tstamp = tmp_tstamp;
1458 	spin_unlock_bh(&ift->lock);
1459 
1460 	addrconf_dad_start(ift);
1461 	in6_ifa_put(ift);
1462 	in6_dev_put(idev);
1463 out:
1464 	return ret;
1465 }
1466 
1467 /*
1468  *	Choose an appropriate source address (RFC3484)
1469  */
1470 enum {
1471 	IPV6_SADDR_RULE_INIT = 0,
1472 	IPV6_SADDR_RULE_LOCAL,
1473 	IPV6_SADDR_RULE_SCOPE,
1474 	IPV6_SADDR_RULE_PREFERRED,
1475 #ifdef CONFIG_IPV6_MIP6
1476 	IPV6_SADDR_RULE_HOA,
1477 #endif
1478 	IPV6_SADDR_RULE_OIF,
1479 	IPV6_SADDR_RULE_LABEL,
1480 	IPV6_SADDR_RULE_PRIVACY,
1481 	IPV6_SADDR_RULE_ORCHID,
1482 	IPV6_SADDR_RULE_PREFIX,
1483 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1484 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1485 #endif
1486 	IPV6_SADDR_RULE_MAX
1487 };
1488 
1489 struct ipv6_saddr_score {
1490 	int			rule;
1491 	int			addr_type;
1492 	struct inet6_ifaddr	*ifa;
1493 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1494 	int			scopedist;
1495 	int			matchlen;
1496 };
1497 
1498 struct ipv6_saddr_dst {
1499 	const struct in6_addr *addr;
1500 	int ifindex;
1501 	int scope;
1502 	int label;
1503 	unsigned int prefs;
1504 };
1505 
1506 static inline int ipv6_saddr_preferred(int type)
1507 {
1508 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1509 		return 1;
1510 	return 0;
1511 }
1512 
1513 static bool ipv6_use_optimistic_addr(struct net *net,
1514 				     struct inet6_dev *idev)
1515 {
1516 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1517 	if (!idev)
1518 		return false;
1519 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1520 		return false;
1521 	if (!net->ipv6.devconf_all->use_optimistic && !idev->cnf.use_optimistic)
1522 		return false;
1523 
1524 	return true;
1525 #else
1526 	return false;
1527 #endif
1528 }
1529 
1530 static bool ipv6_allow_optimistic_dad(struct net *net,
1531 				      struct inet6_dev *idev)
1532 {
1533 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1534 	if (!idev)
1535 		return false;
1536 	if (!net->ipv6.devconf_all->optimistic_dad && !idev->cnf.optimistic_dad)
1537 		return false;
1538 
1539 	return true;
1540 #else
1541 	return false;
1542 #endif
1543 }
1544 
1545 static int ipv6_get_saddr_eval(struct net *net,
1546 			       struct ipv6_saddr_score *score,
1547 			       struct ipv6_saddr_dst *dst,
1548 			       int i)
1549 {
1550 	int ret;
1551 
1552 	if (i <= score->rule) {
1553 		switch (i) {
1554 		case IPV6_SADDR_RULE_SCOPE:
1555 			ret = score->scopedist;
1556 			break;
1557 		case IPV6_SADDR_RULE_PREFIX:
1558 			ret = score->matchlen;
1559 			break;
1560 		default:
1561 			ret = !!test_bit(i, score->scorebits);
1562 		}
1563 		goto out;
1564 	}
1565 
1566 	switch (i) {
1567 	case IPV6_SADDR_RULE_INIT:
1568 		/* Rule 0: remember if hiscore is not ready yet */
1569 		ret = !!score->ifa;
1570 		break;
1571 	case IPV6_SADDR_RULE_LOCAL:
1572 		/* Rule 1: Prefer same address */
1573 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1574 		break;
1575 	case IPV6_SADDR_RULE_SCOPE:
1576 		/* Rule 2: Prefer appropriate scope
1577 		 *
1578 		 *      ret
1579 		 *       ^
1580 		 *    -1 |  d 15
1581 		 *    ---+--+-+---> scope
1582 		 *       |
1583 		 *       |             d is scope of the destination.
1584 		 *  B-d  |  \
1585 		 *       |   \      <- smaller scope is better if
1586 		 *  B-15 |    \        if scope is enough for destination.
1587 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1588 		 * d-C-1 | /
1589 		 *       |/         <- greater is better
1590 		 *   -C  /             if scope is not enough for destination.
1591 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1592 		 *
1593 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1594 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1595 		 * Assume B = 0 and we get C > 29.
1596 		 */
1597 		ret = __ipv6_addr_src_scope(score->addr_type);
1598 		if (ret >= dst->scope)
1599 			ret = -ret;
1600 		else
1601 			ret -= 128;	/* 30 is enough */
1602 		score->scopedist = ret;
1603 		break;
1604 	case IPV6_SADDR_RULE_PREFERRED:
1605 	    {
1606 		/* Rule 3: Avoid deprecated and optimistic addresses */
1607 		u8 avoid = IFA_F_DEPRECATED;
1608 
1609 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1610 			avoid |= IFA_F_OPTIMISTIC;
1611 		ret = ipv6_saddr_preferred(score->addr_type) ||
1612 		      !(score->ifa->flags & avoid);
1613 		break;
1614 	    }
1615 #ifdef CONFIG_IPV6_MIP6
1616 	case IPV6_SADDR_RULE_HOA:
1617 	    {
1618 		/* Rule 4: Prefer home address */
1619 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1620 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1621 		break;
1622 	    }
1623 #endif
1624 	case IPV6_SADDR_RULE_OIF:
1625 		/* Rule 5: Prefer outgoing interface */
1626 		ret = (!dst->ifindex ||
1627 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1628 		break;
1629 	case IPV6_SADDR_RULE_LABEL:
1630 		/* Rule 6: Prefer matching label */
1631 		ret = ipv6_addr_label(net,
1632 				      &score->ifa->addr, score->addr_type,
1633 				      score->ifa->idev->dev->ifindex) == dst->label;
1634 		break;
1635 	case IPV6_SADDR_RULE_PRIVACY:
1636 	    {
1637 		/* Rule 7: Prefer public address
1638 		 * Note: prefer temporary address if use_tempaddr >= 2
1639 		 */
1640 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1641 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1642 				score->ifa->idev->cnf.use_tempaddr >= 2;
1643 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1644 		break;
1645 	    }
1646 	case IPV6_SADDR_RULE_ORCHID:
1647 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1648 		 *	    non-ORCHID vs non-ORCHID
1649 		 */
1650 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1651 			ipv6_addr_orchid(dst->addr));
1652 		break;
1653 	case IPV6_SADDR_RULE_PREFIX:
1654 		/* Rule 8: Use longest matching prefix */
1655 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1656 		if (ret > score->ifa->prefix_len)
1657 			ret = score->ifa->prefix_len;
1658 		score->matchlen = ret;
1659 		break;
1660 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1661 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1662 		/* Optimistic addresses still have lower precedence than other
1663 		 * preferred addresses.
1664 		 */
1665 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1666 		break;
1667 #endif
1668 	default:
1669 		ret = 0;
1670 	}
1671 
1672 	if (ret)
1673 		__set_bit(i, score->scorebits);
1674 	score->rule = i;
1675 out:
1676 	return ret;
1677 }
1678 
1679 static int __ipv6_dev_get_saddr(struct net *net,
1680 				struct ipv6_saddr_dst *dst,
1681 				struct inet6_dev *idev,
1682 				struct ipv6_saddr_score *scores,
1683 				int hiscore_idx)
1684 {
1685 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1686 
1687 	list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1688 		int i;
1689 
1690 		/*
1691 		 * - Tentative Address (RFC2462 section 5.4)
1692 		 *  - A tentative address is not considered
1693 		 *    "assigned to an interface" in the traditional
1694 		 *    sense, unless it is also flagged as optimistic.
1695 		 * - Candidate Source Address (section 4)
1696 		 *  - In any case, anycast addresses, multicast
1697 		 *    addresses, and the unspecified address MUST
1698 		 *    NOT be included in a candidate set.
1699 		 */
1700 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1701 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1702 			continue;
1703 
1704 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1705 
1706 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1707 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1708 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1709 					    idev->dev->name);
1710 			continue;
1711 		}
1712 
1713 		score->rule = -1;
1714 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1715 
1716 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1717 			int minihiscore, miniscore;
1718 
1719 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1720 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1721 
1722 			if (minihiscore > miniscore) {
1723 				if (i == IPV6_SADDR_RULE_SCOPE &&
1724 				    score->scopedist > 0) {
1725 					/*
1726 					 * special case:
1727 					 * each remaining entry
1728 					 * has too small (not enough)
1729 					 * scope, because ifa entries
1730 					 * are sorted by their scope
1731 					 * values.
1732 					 */
1733 					goto out;
1734 				}
1735 				break;
1736 			} else if (minihiscore < miniscore) {
1737 				swap(hiscore, score);
1738 				hiscore_idx = 1 - hiscore_idx;
1739 
1740 				/* restore our iterator */
1741 				score->ifa = hiscore->ifa;
1742 
1743 				break;
1744 			}
1745 		}
1746 	}
1747 out:
1748 	return hiscore_idx;
1749 }
1750 
1751 static int ipv6_get_saddr_master(struct net *net,
1752 				 const struct net_device *dst_dev,
1753 				 const struct net_device *master,
1754 				 struct ipv6_saddr_dst *dst,
1755 				 struct ipv6_saddr_score *scores,
1756 				 int hiscore_idx)
1757 {
1758 	struct inet6_dev *idev;
1759 
1760 	idev = __in6_dev_get(dst_dev);
1761 	if (idev)
1762 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1763 						   scores, hiscore_idx);
1764 
1765 	idev = __in6_dev_get(master);
1766 	if (idev)
1767 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1768 						   scores, hiscore_idx);
1769 
1770 	return hiscore_idx;
1771 }
1772 
1773 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1774 		       const struct in6_addr *daddr, unsigned int prefs,
1775 		       struct in6_addr *saddr)
1776 {
1777 	struct ipv6_saddr_score scores[2], *hiscore;
1778 	struct ipv6_saddr_dst dst;
1779 	struct inet6_dev *idev;
1780 	struct net_device *dev;
1781 	int dst_type;
1782 	bool use_oif_addr = false;
1783 	int hiscore_idx = 0;
1784 	int ret = 0;
1785 
1786 	dst_type = __ipv6_addr_type(daddr);
1787 	dst.addr = daddr;
1788 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1789 	dst.scope = __ipv6_addr_src_scope(dst_type);
1790 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1791 	dst.prefs = prefs;
1792 
1793 	scores[hiscore_idx].rule = -1;
1794 	scores[hiscore_idx].ifa = NULL;
1795 
1796 	rcu_read_lock();
1797 
1798 	/* Candidate Source Address (section 4)
1799 	 *  - multicast and link-local destination address,
1800 	 *    the set of candidate source address MUST only
1801 	 *    include addresses assigned to interfaces
1802 	 *    belonging to the same link as the outgoing
1803 	 *    interface.
1804 	 * (- For site-local destination addresses, the
1805 	 *    set of candidate source addresses MUST only
1806 	 *    include addresses assigned to interfaces
1807 	 *    belonging to the same site as the outgoing
1808 	 *    interface.)
1809 	 *  - "It is RECOMMENDED that the candidate source addresses
1810 	 *    be the set of unicast addresses assigned to the
1811 	 *    interface that will be used to send to the destination
1812 	 *    (the 'outgoing' interface)." (RFC 6724)
1813 	 */
1814 	if (dst_dev) {
1815 		idev = __in6_dev_get(dst_dev);
1816 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1817 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1818 		    (idev && idev->cnf.use_oif_addrs_only)) {
1819 			use_oif_addr = true;
1820 		}
1821 	}
1822 
1823 	if (use_oif_addr) {
1824 		if (idev)
1825 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1826 	} else {
1827 		const struct net_device *master;
1828 		int master_idx = 0;
1829 
1830 		/* if dst_dev exists and is enslaved to an L3 device, then
1831 		 * prefer addresses from dst_dev and then the master over
1832 		 * any other enslaved devices in the L3 domain.
1833 		 */
1834 		master = l3mdev_master_dev_rcu(dst_dev);
1835 		if (master) {
1836 			master_idx = master->ifindex;
1837 
1838 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1839 							    master, &dst,
1840 							    scores, hiscore_idx);
1841 
1842 			if (scores[hiscore_idx].ifa)
1843 				goto out;
1844 		}
1845 
1846 		for_each_netdev_rcu(net, dev) {
1847 			/* only consider addresses on devices in the
1848 			 * same L3 domain
1849 			 */
1850 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1851 				continue;
1852 			idev = __in6_dev_get(dev);
1853 			if (!idev)
1854 				continue;
1855 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1856 		}
1857 	}
1858 
1859 out:
1860 	hiscore = &scores[hiscore_idx];
1861 	if (!hiscore->ifa)
1862 		ret = -EADDRNOTAVAIL;
1863 	else
1864 		*saddr = hiscore->ifa->addr;
1865 
1866 	rcu_read_unlock();
1867 	return ret;
1868 }
1869 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1870 
1871 static int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1872 			      u32 banned_flags)
1873 {
1874 	struct inet6_ifaddr *ifp;
1875 	int err = -EADDRNOTAVAIL;
1876 
1877 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1878 		if (ifp->scope > IFA_LINK)
1879 			break;
1880 		if (ifp->scope == IFA_LINK &&
1881 		    !(ifp->flags & banned_flags)) {
1882 			*addr = ifp->addr;
1883 			err = 0;
1884 			break;
1885 		}
1886 	}
1887 	return err;
1888 }
1889 
1890 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1891 		    u32 banned_flags)
1892 {
1893 	struct inet6_dev *idev;
1894 	int err = -EADDRNOTAVAIL;
1895 
1896 	rcu_read_lock();
1897 	idev = __in6_dev_get(dev);
1898 	if (idev) {
1899 		read_lock_bh(&idev->lock);
1900 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1901 		read_unlock_bh(&idev->lock);
1902 	}
1903 	rcu_read_unlock();
1904 	return err;
1905 }
1906 
1907 static int ipv6_count_addresses(const struct inet6_dev *idev)
1908 {
1909 	const struct inet6_ifaddr *ifp;
1910 	int cnt = 0;
1911 
1912 	rcu_read_lock();
1913 	list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1914 		cnt++;
1915 	rcu_read_unlock();
1916 	return cnt;
1917 }
1918 
1919 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1920 		  const struct net_device *dev, int strict)
1921 {
1922 	return ipv6_chk_addr_and_flags(net, addr, dev, !dev,
1923 				       strict, IFA_F_TENTATIVE);
1924 }
1925 EXPORT_SYMBOL(ipv6_chk_addr);
1926 
1927 /* device argument is used to find the L3 domain of interest. If
1928  * skip_dev_check is set, then the ifp device is not checked against
1929  * the passed in dev argument. So the 2 cases for addresses checks are:
1930  *   1. does the address exist in the L3 domain that dev is part of
1931  *      (skip_dev_check = true), or
1932  *
1933  *   2. does the address exist on the specific device
1934  *      (skip_dev_check = false)
1935  */
1936 static struct net_device *
1937 __ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1938 			  const struct net_device *dev, bool skip_dev_check,
1939 			  int strict, u32 banned_flags)
1940 {
1941 	unsigned int hash = inet6_addr_hash(net, addr);
1942 	struct net_device *l3mdev, *ndev;
1943 	struct inet6_ifaddr *ifp;
1944 	u32 ifp_flags;
1945 
1946 	rcu_read_lock();
1947 
1948 	l3mdev = l3mdev_master_dev_rcu(dev);
1949 	if (skip_dev_check)
1950 		dev = NULL;
1951 
1952 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
1953 		ndev = ifp->idev->dev;
1954 
1955 		if (l3mdev_master_dev_rcu(ndev) != l3mdev)
1956 			continue;
1957 
1958 		/* Decouple optimistic from tentative for evaluation here.
1959 		 * Ban optimistic addresses explicitly, when required.
1960 		 */
1961 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1962 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1963 			    : ifp->flags;
1964 		if (ipv6_addr_equal(&ifp->addr, addr) &&
1965 		    !(ifp_flags&banned_flags) &&
1966 		    (!dev || ndev == dev ||
1967 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
1968 			rcu_read_unlock();
1969 			return ndev;
1970 		}
1971 	}
1972 
1973 	rcu_read_unlock();
1974 	return NULL;
1975 }
1976 
1977 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1978 			    const struct net_device *dev, bool skip_dev_check,
1979 			    int strict, u32 banned_flags)
1980 {
1981 	return __ipv6_chk_addr_and_flags(net, addr, dev, skip_dev_check,
1982 					 strict, banned_flags) ? 1 : 0;
1983 }
1984 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
1985 
1986 
1987 /* Compares an address/prefix_len with addresses on device @dev.
1988  * If one is found it returns true.
1989  */
1990 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
1991 	const unsigned int prefix_len, struct net_device *dev)
1992 {
1993 	const struct inet6_ifaddr *ifa;
1994 	const struct inet6_dev *idev;
1995 	bool ret = false;
1996 
1997 	rcu_read_lock();
1998 	idev = __in6_dev_get(dev);
1999 	if (idev) {
2000 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
2001 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
2002 			if (ret)
2003 				break;
2004 		}
2005 	}
2006 	rcu_read_unlock();
2007 
2008 	return ret;
2009 }
2010 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
2011 
2012 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
2013 {
2014 	const struct inet6_ifaddr *ifa;
2015 	const struct inet6_dev *idev;
2016 	int	onlink;
2017 
2018 	onlink = 0;
2019 	rcu_read_lock();
2020 	idev = __in6_dev_get(dev);
2021 	if (idev) {
2022 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
2023 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
2024 						   ifa->prefix_len);
2025 			if (onlink)
2026 				break;
2027 		}
2028 	}
2029 	rcu_read_unlock();
2030 	return onlink;
2031 }
2032 EXPORT_SYMBOL(ipv6_chk_prefix);
2033 
2034 /**
2035  * ipv6_dev_find - find the first device with a given source address.
2036  * @net: the net namespace
2037  * @addr: the source address
2038  * @dev: used to find the L3 domain of interest
2039  *
2040  * The caller should be protected by RCU, or RTNL.
2041  */
2042 struct net_device *ipv6_dev_find(struct net *net, const struct in6_addr *addr,
2043 				 struct net_device *dev)
2044 {
2045 	return __ipv6_chk_addr_and_flags(net, addr, dev, !dev, 1,
2046 					 IFA_F_TENTATIVE);
2047 }
2048 EXPORT_SYMBOL(ipv6_dev_find);
2049 
2050 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
2051 				     struct net_device *dev, int strict)
2052 {
2053 	unsigned int hash = inet6_addr_hash(net, addr);
2054 	struct inet6_ifaddr *ifp, *result = NULL;
2055 
2056 	rcu_read_lock();
2057 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
2058 		if (ipv6_addr_equal(&ifp->addr, addr)) {
2059 			if (!dev || ifp->idev->dev == dev ||
2060 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
2061 				if (in6_ifa_hold_safe(ifp)) {
2062 					result = ifp;
2063 					break;
2064 				}
2065 			}
2066 		}
2067 	}
2068 	rcu_read_unlock();
2069 
2070 	return result;
2071 }
2072 
2073 /* Gets referenced address, destroys ifaddr */
2074 
2075 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
2076 {
2077 	if (dad_failed)
2078 		ifp->flags |= IFA_F_DADFAILED;
2079 
2080 	if (ifp->flags&IFA_F_TEMPORARY) {
2081 		struct inet6_ifaddr *ifpub;
2082 		spin_lock_bh(&ifp->lock);
2083 		ifpub = ifp->ifpub;
2084 		if (ifpub) {
2085 			in6_ifa_hold(ifpub);
2086 			spin_unlock_bh(&ifp->lock);
2087 			ipv6_create_tempaddr(ifpub, true);
2088 			in6_ifa_put(ifpub);
2089 		} else {
2090 			spin_unlock_bh(&ifp->lock);
2091 		}
2092 		ipv6_del_addr(ifp);
2093 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
2094 		spin_lock_bh(&ifp->lock);
2095 		addrconf_del_dad_work(ifp);
2096 		ifp->flags |= IFA_F_TENTATIVE;
2097 		if (dad_failed)
2098 			ifp->flags &= ~IFA_F_OPTIMISTIC;
2099 		spin_unlock_bh(&ifp->lock);
2100 		if (dad_failed)
2101 			ipv6_ifa_notify(0, ifp);
2102 		in6_ifa_put(ifp);
2103 	} else {
2104 		ipv6_del_addr(ifp);
2105 	}
2106 }
2107 
2108 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
2109 {
2110 	int err = -ENOENT;
2111 
2112 	spin_lock_bh(&ifp->lock);
2113 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
2114 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
2115 		err = 0;
2116 	}
2117 	spin_unlock_bh(&ifp->lock);
2118 
2119 	return err;
2120 }
2121 
2122 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp)
2123 {
2124 	struct inet6_dev *idev = ifp->idev;
2125 	struct net *net = dev_net(idev->dev);
2126 
2127 	if (addrconf_dad_end(ifp)) {
2128 		in6_ifa_put(ifp);
2129 		return;
2130 	}
2131 
2132 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c used by %pM detected!\n",
2133 			     ifp->idev->dev->name, &ifp->addr, eth_hdr(skb)->h_source);
2134 
2135 	spin_lock_bh(&ifp->lock);
2136 
2137 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2138 		struct in6_addr new_addr;
2139 		struct inet6_ifaddr *ifp2;
2140 		int retries = ifp->stable_privacy_retry + 1;
2141 		struct ifa6_config cfg = {
2142 			.pfx = &new_addr,
2143 			.plen = ifp->prefix_len,
2144 			.ifa_flags = ifp->flags,
2145 			.valid_lft = ifp->valid_lft,
2146 			.preferred_lft = ifp->prefered_lft,
2147 			.scope = ifp->scope,
2148 		};
2149 
2150 		if (retries > net->ipv6.sysctl.idgen_retries) {
2151 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2152 					     ifp->idev->dev->name);
2153 			goto errdad;
2154 		}
2155 
2156 		new_addr = ifp->addr;
2157 		if (ipv6_generate_stable_address(&new_addr, retries,
2158 						 idev))
2159 			goto errdad;
2160 
2161 		spin_unlock_bh(&ifp->lock);
2162 
2163 		if (idev->cnf.max_addresses &&
2164 		    ipv6_count_addresses(idev) >=
2165 		    idev->cnf.max_addresses)
2166 			goto lock_errdad;
2167 
2168 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2169 				     ifp->idev->dev->name);
2170 
2171 		ifp2 = ipv6_add_addr(idev, &cfg, false, NULL);
2172 		if (IS_ERR(ifp2))
2173 			goto lock_errdad;
2174 
2175 		spin_lock_bh(&ifp2->lock);
2176 		ifp2->stable_privacy_retry = retries;
2177 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2178 		spin_unlock_bh(&ifp2->lock);
2179 
2180 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2181 		in6_ifa_put(ifp2);
2182 lock_errdad:
2183 		spin_lock_bh(&ifp->lock);
2184 	}
2185 
2186 errdad:
2187 	/* transition from _POSTDAD to _ERRDAD */
2188 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2189 	spin_unlock_bh(&ifp->lock);
2190 
2191 	addrconf_mod_dad_work(ifp, 0);
2192 	in6_ifa_put(ifp);
2193 }
2194 
2195 /* Join to solicited addr multicast group.
2196  * caller must hold RTNL */
2197 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2198 {
2199 	struct in6_addr maddr;
2200 
2201 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2202 		return;
2203 
2204 	addrconf_addr_solict_mult(addr, &maddr);
2205 	ipv6_dev_mc_inc(dev, &maddr);
2206 }
2207 
2208 /* caller must hold RTNL */
2209 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2210 {
2211 	struct in6_addr maddr;
2212 
2213 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2214 		return;
2215 
2216 	addrconf_addr_solict_mult(addr, &maddr);
2217 	__ipv6_dev_mc_dec(idev, &maddr);
2218 }
2219 
2220 /* caller must hold RTNL */
2221 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2222 {
2223 	struct in6_addr addr;
2224 
2225 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2226 		return;
2227 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2228 	if (ipv6_addr_any(&addr))
2229 		return;
2230 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2231 }
2232 
2233 /* caller must hold RTNL */
2234 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2235 {
2236 	struct in6_addr addr;
2237 
2238 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2239 		return;
2240 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2241 	if (ipv6_addr_any(&addr))
2242 		return;
2243 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2244 }
2245 
2246 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2247 {
2248 	switch (dev->addr_len) {
2249 	case ETH_ALEN:
2250 		memcpy(eui, dev->dev_addr, 3);
2251 		eui[3] = 0xFF;
2252 		eui[4] = 0xFE;
2253 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2254 		break;
2255 	case EUI64_ADDR_LEN:
2256 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2257 		eui[0] ^= 2;
2258 		break;
2259 	default:
2260 		return -1;
2261 	}
2262 
2263 	return 0;
2264 }
2265 
2266 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2267 {
2268 	const union fwnet_hwaddr *ha;
2269 
2270 	if (dev->addr_len != FWNET_ALEN)
2271 		return -1;
2272 
2273 	ha = (const union fwnet_hwaddr *)dev->dev_addr;
2274 
2275 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2276 	eui[0] ^= 2;
2277 	return 0;
2278 }
2279 
2280 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2281 {
2282 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2283 	if (dev->addr_len != ARCNET_ALEN)
2284 		return -1;
2285 	memset(eui, 0, 7);
2286 	eui[7] = *(u8 *)dev->dev_addr;
2287 	return 0;
2288 }
2289 
2290 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2291 {
2292 	if (dev->addr_len != INFINIBAND_ALEN)
2293 		return -1;
2294 	memcpy(eui, dev->dev_addr + 12, 8);
2295 	eui[0] |= 2;
2296 	return 0;
2297 }
2298 
2299 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2300 {
2301 	if (addr == 0)
2302 		return -1;
2303 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2304 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2305 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2306 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2307 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2308 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2309 	eui[1] = 0;
2310 	eui[2] = 0x5E;
2311 	eui[3] = 0xFE;
2312 	memcpy(eui + 4, &addr, 4);
2313 	return 0;
2314 }
2315 
2316 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2317 {
2318 	if (dev->priv_flags & IFF_ISATAP)
2319 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2320 	return -1;
2321 }
2322 
2323 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2324 {
2325 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2326 }
2327 
2328 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2329 {
2330 	memcpy(eui, dev->perm_addr, 3);
2331 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2332 	eui[3] = 0xFF;
2333 	eui[4] = 0xFE;
2334 	eui[0] ^= 2;
2335 	return 0;
2336 }
2337 
2338 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2339 {
2340 	switch (dev->type) {
2341 	case ARPHRD_ETHER:
2342 	case ARPHRD_FDDI:
2343 		return addrconf_ifid_eui48(eui, dev);
2344 	case ARPHRD_ARCNET:
2345 		return addrconf_ifid_arcnet(eui, dev);
2346 	case ARPHRD_INFINIBAND:
2347 		return addrconf_ifid_infiniband(eui, dev);
2348 	case ARPHRD_SIT:
2349 		return addrconf_ifid_sit(eui, dev);
2350 	case ARPHRD_IPGRE:
2351 	case ARPHRD_TUNNEL:
2352 		return addrconf_ifid_gre(eui, dev);
2353 	case ARPHRD_6LOWPAN:
2354 		return addrconf_ifid_6lowpan(eui, dev);
2355 	case ARPHRD_IEEE1394:
2356 		return addrconf_ifid_ieee1394(eui, dev);
2357 	case ARPHRD_TUNNEL6:
2358 	case ARPHRD_IP6GRE:
2359 	case ARPHRD_RAWIP:
2360 		return addrconf_ifid_ip6tnl(eui, dev);
2361 	}
2362 	return -1;
2363 }
2364 
2365 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2366 {
2367 	int err = -1;
2368 	struct inet6_ifaddr *ifp;
2369 
2370 	read_lock_bh(&idev->lock);
2371 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2372 		if (ifp->scope > IFA_LINK)
2373 			break;
2374 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2375 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2376 			err = 0;
2377 			break;
2378 		}
2379 	}
2380 	read_unlock_bh(&idev->lock);
2381 	return err;
2382 }
2383 
2384 /* Generation of a randomized Interface Identifier
2385  * draft-ietf-6man-rfc4941bis, Section 3.3.1
2386  */
2387 
2388 static void ipv6_gen_rnd_iid(struct in6_addr *addr)
2389 {
2390 regen:
2391 	get_random_bytes(&addr->s6_addr[8], 8);
2392 
2393 	/* <draft-ietf-6man-rfc4941bis-08.txt>, Section 3.3.1:
2394 	 * check if generated address is not inappropriate:
2395 	 *
2396 	 * - Reserved IPv6 Interface Identifiers
2397 	 * - XXX: already assigned to an address on the device
2398 	 */
2399 
2400 	/* Subnet-router anycast: 0000:0000:0000:0000 */
2401 	if (!(addr->s6_addr32[2] | addr->s6_addr32[3]))
2402 		goto regen;
2403 
2404 	/* IANA Ethernet block: 0200:5EFF:FE00:0000-0200:5EFF:FE00:5212
2405 	 * Proxy Mobile IPv6:   0200:5EFF:FE00:5213
2406 	 * IANA Ethernet block: 0200:5EFF:FE00:5214-0200:5EFF:FEFF:FFFF
2407 	 */
2408 	if (ntohl(addr->s6_addr32[2]) == 0x02005eff &&
2409 	    (ntohl(addr->s6_addr32[3]) & 0Xff000000) == 0xfe000000)
2410 		goto regen;
2411 
2412 	/* Reserved subnet anycast addresses */
2413 	if (ntohl(addr->s6_addr32[2]) == 0xfdffffff &&
2414 	    ntohl(addr->s6_addr32[3]) >= 0Xffffff80)
2415 		goto regen;
2416 }
2417 
2418 /*
2419  *	Add prefix route.
2420  */
2421 
2422 static void
2423 addrconf_prefix_route(struct in6_addr *pfx, int plen, u32 metric,
2424 		      struct net_device *dev, unsigned long expires,
2425 		      u32 flags, gfp_t gfp_flags)
2426 {
2427 	struct fib6_config cfg = {
2428 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2429 		.fc_metric = metric ? : IP6_RT_PRIO_ADDRCONF,
2430 		.fc_ifindex = dev->ifindex,
2431 		.fc_expires = expires,
2432 		.fc_dst_len = plen,
2433 		.fc_flags = RTF_UP | flags,
2434 		.fc_nlinfo.nl_net = dev_net(dev),
2435 		.fc_protocol = RTPROT_KERNEL,
2436 		.fc_type = RTN_UNICAST,
2437 	};
2438 
2439 	cfg.fc_dst = *pfx;
2440 
2441 	/* Prevent useless cloning on PtP SIT.
2442 	   This thing is done here expecting that the whole
2443 	   class of non-broadcast devices need not cloning.
2444 	 */
2445 #if IS_ENABLED(CONFIG_IPV6_SIT)
2446 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2447 		cfg.fc_flags |= RTF_NONEXTHOP;
2448 #endif
2449 
2450 	ip6_route_add(&cfg, gfp_flags, NULL);
2451 }
2452 
2453 
2454 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2455 						  int plen,
2456 						  const struct net_device *dev,
2457 						  u32 flags, u32 noflags,
2458 						  bool no_gw)
2459 {
2460 	struct fib6_node *fn;
2461 	struct fib6_info *rt = NULL;
2462 	struct fib6_table *table;
2463 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2464 
2465 	table = fib6_get_table(dev_net(dev), tb_id);
2466 	if (!table)
2467 		return NULL;
2468 
2469 	rcu_read_lock();
2470 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2471 	if (!fn)
2472 		goto out;
2473 
2474 	for_each_fib6_node_rt_rcu(fn) {
2475 		/* prefix routes only use builtin fib6_nh */
2476 		if (rt->nh)
2477 			continue;
2478 
2479 		if (rt->fib6_nh->fib_nh_dev->ifindex != dev->ifindex)
2480 			continue;
2481 		if (no_gw && rt->fib6_nh->fib_nh_gw_family)
2482 			continue;
2483 		if ((rt->fib6_flags & flags) != flags)
2484 			continue;
2485 		if ((rt->fib6_flags & noflags) != 0)
2486 			continue;
2487 		if (!fib6_info_hold_safe(rt))
2488 			continue;
2489 		break;
2490 	}
2491 out:
2492 	rcu_read_unlock();
2493 	return rt;
2494 }
2495 
2496 
2497 /* Create "default" multicast route to the interface */
2498 
2499 static void addrconf_add_mroute(struct net_device *dev)
2500 {
2501 	struct fib6_config cfg = {
2502 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2503 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2504 		.fc_ifindex = dev->ifindex,
2505 		.fc_dst_len = 8,
2506 		.fc_flags = RTF_UP,
2507 		.fc_type = RTN_MULTICAST,
2508 		.fc_nlinfo.nl_net = dev_net(dev),
2509 		.fc_protocol = RTPROT_KERNEL,
2510 	};
2511 
2512 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2513 
2514 	ip6_route_add(&cfg, GFP_KERNEL, NULL);
2515 }
2516 
2517 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2518 {
2519 	struct inet6_dev *idev;
2520 
2521 	ASSERT_RTNL();
2522 
2523 	idev = ipv6_find_idev(dev);
2524 	if (IS_ERR(idev))
2525 		return idev;
2526 
2527 	if (idev->cnf.disable_ipv6)
2528 		return ERR_PTR(-EACCES);
2529 
2530 	/* Add default multicast route */
2531 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2532 		addrconf_add_mroute(dev);
2533 
2534 	return idev;
2535 }
2536 
2537 static void manage_tempaddrs(struct inet6_dev *idev,
2538 			     struct inet6_ifaddr *ifp,
2539 			     __u32 valid_lft, __u32 prefered_lft,
2540 			     bool create, unsigned long now)
2541 {
2542 	u32 flags;
2543 	struct inet6_ifaddr *ift;
2544 
2545 	read_lock_bh(&idev->lock);
2546 	/* update all temporary addresses in the list */
2547 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2548 		int age, max_valid, max_prefered;
2549 
2550 		if (ifp != ift->ifpub)
2551 			continue;
2552 
2553 		/* RFC 4941 section 3.3:
2554 		 * If a received option will extend the lifetime of a public
2555 		 * address, the lifetimes of temporary addresses should
2556 		 * be extended, subject to the overall constraint that no
2557 		 * temporary addresses should ever remain "valid" or "preferred"
2558 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2559 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2560 		 */
2561 		age = (now - ift->cstamp) / HZ;
2562 		max_valid = idev->cnf.temp_valid_lft - age;
2563 		if (max_valid < 0)
2564 			max_valid = 0;
2565 
2566 		max_prefered = idev->cnf.temp_prefered_lft -
2567 			       idev->desync_factor - age;
2568 		if (max_prefered < 0)
2569 			max_prefered = 0;
2570 
2571 		if (valid_lft > max_valid)
2572 			valid_lft = max_valid;
2573 
2574 		if (prefered_lft > max_prefered)
2575 			prefered_lft = max_prefered;
2576 
2577 		spin_lock(&ift->lock);
2578 		flags = ift->flags;
2579 		ift->valid_lft = valid_lft;
2580 		ift->prefered_lft = prefered_lft;
2581 		ift->tstamp = now;
2582 		if (prefered_lft > 0)
2583 			ift->flags &= ~IFA_F_DEPRECATED;
2584 
2585 		spin_unlock(&ift->lock);
2586 		if (!(flags&IFA_F_TENTATIVE))
2587 			ipv6_ifa_notify(0, ift);
2588 	}
2589 
2590 	/* Also create a temporary address if it's enabled but no temporary
2591 	 * address currently exists.
2592 	 * However, we get called with valid_lft == 0, prefered_lft == 0, create == false
2593 	 * as part of cleanup (ie. deleting the mngtmpaddr).
2594 	 * We don't want that to result in creating a new temporary ip address.
2595 	 */
2596 	if (list_empty(&idev->tempaddr_list) && (valid_lft || prefered_lft))
2597 		create = true;
2598 
2599 	if (create && idev->cnf.use_tempaddr > 0) {
2600 		/* When a new public address is created as described
2601 		 * in [ADDRCONF], also create a new temporary address.
2602 		 */
2603 		read_unlock_bh(&idev->lock);
2604 		ipv6_create_tempaddr(ifp, false);
2605 	} else {
2606 		read_unlock_bh(&idev->lock);
2607 	}
2608 }
2609 
2610 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2611 {
2612 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2613 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2614 }
2615 
2616 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2617 				 const struct prefix_info *pinfo,
2618 				 struct inet6_dev *in6_dev,
2619 				 const struct in6_addr *addr, int addr_type,
2620 				 u32 addr_flags, bool sllao, bool tokenized,
2621 				 __u32 valid_lft, u32 prefered_lft)
2622 {
2623 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2624 	int create = 0, update_lft = 0;
2625 
2626 	if (!ifp && valid_lft) {
2627 		int max_addresses = in6_dev->cnf.max_addresses;
2628 		struct ifa6_config cfg = {
2629 			.pfx = addr,
2630 			.plen = pinfo->prefix_len,
2631 			.ifa_flags = addr_flags,
2632 			.valid_lft = valid_lft,
2633 			.preferred_lft = prefered_lft,
2634 			.scope = addr_type & IPV6_ADDR_SCOPE_MASK,
2635 			.ifa_proto = IFAPROT_KERNEL_RA
2636 		};
2637 
2638 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2639 		if ((net->ipv6.devconf_all->optimistic_dad ||
2640 		     in6_dev->cnf.optimistic_dad) &&
2641 		    !net->ipv6.devconf_all->forwarding && sllao)
2642 			cfg.ifa_flags |= IFA_F_OPTIMISTIC;
2643 #endif
2644 
2645 		/* Do not allow to create too much of autoconfigured
2646 		 * addresses; this would be too easy way to crash kernel.
2647 		 */
2648 		if (!max_addresses ||
2649 		    ipv6_count_addresses(in6_dev) < max_addresses)
2650 			ifp = ipv6_add_addr(in6_dev, &cfg, false, NULL);
2651 
2652 		if (IS_ERR_OR_NULL(ifp))
2653 			return -1;
2654 
2655 		create = 1;
2656 		spin_lock_bh(&ifp->lock);
2657 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2658 		ifp->cstamp = jiffies;
2659 		ifp->tokenized = tokenized;
2660 		spin_unlock_bh(&ifp->lock);
2661 		addrconf_dad_start(ifp);
2662 	}
2663 
2664 	if (ifp) {
2665 		u32 flags;
2666 		unsigned long now;
2667 		u32 stored_lft;
2668 
2669 		/* update lifetime (RFC2462 5.5.3 e) */
2670 		spin_lock_bh(&ifp->lock);
2671 		now = jiffies;
2672 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2673 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2674 		else
2675 			stored_lft = 0;
2676 		if (!create && stored_lft) {
2677 			const u32 minimum_lft = min_t(u32,
2678 				stored_lft, MIN_VALID_LIFETIME);
2679 			valid_lft = max(valid_lft, minimum_lft);
2680 
2681 			/* RFC4862 Section 5.5.3e:
2682 			 * "Note that the preferred lifetime of the
2683 			 *  corresponding address is always reset to
2684 			 *  the Preferred Lifetime in the received
2685 			 *  Prefix Information option, regardless of
2686 			 *  whether the valid lifetime is also reset or
2687 			 *  ignored."
2688 			 *
2689 			 * So we should always update prefered_lft here.
2690 			 */
2691 			update_lft = 1;
2692 		}
2693 
2694 		if (update_lft) {
2695 			ifp->valid_lft = valid_lft;
2696 			ifp->prefered_lft = prefered_lft;
2697 			ifp->tstamp = now;
2698 			flags = ifp->flags;
2699 			ifp->flags &= ~IFA_F_DEPRECATED;
2700 			spin_unlock_bh(&ifp->lock);
2701 
2702 			if (!(flags&IFA_F_TENTATIVE))
2703 				ipv6_ifa_notify(0, ifp);
2704 		} else
2705 			spin_unlock_bh(&ifp->lock);
2706 
2707 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2708 				 create, now);
2709 
2710 		in6_ifa_put(ifp);
2711 		addrconf_verify(net);
2712 	}
2713 
2714 	return 0;
2715 }
2716 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2717 
2718 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2719 {
2720 	struct prefix_info *pinfo;
2721 	__u32 valid_lft;
2722 	__u32 prefered_lft;
2723 	int addr_type, err;
2724 	u32 addr_flags = 0;
2725 	struct inet6_dev *in6_dev;
2726 	struct net *net = dev_net(dev);
2727 
2728 	pinfo = (struct prefix_info *) opt;
2729 
2730 	if (len < sizeof(struct prefix_info)) {
2731 		netdev_dbg(dev, "addrconf: prefix option too short\n");
2732 		return;
2733 	}
2734 
2735 	/*
2736 	 *	Validation checks ([ADDRCONF], page 19)
2737 	 */
2738 
2739 	addr_type = ipv6_addr_type(&pinfo->prefix);
2740 
2741 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2742 		return;
2743 
2744 	valid_lft = ntohl(pinfo->valid);
2745 	prefered_lft = ntohl(pinfo->prefered);
2746 
2747 	if (prefered_lft > valid_lft) {
2748 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2749 		return;
2750 	}
2751 
2752 	in6_dev = in6_dev_get(dev);
2753 
2754 	if (!in6_dev) {
2755 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2756 				    dev->name);
2757 		return;
2758 	}
2759 
2760 	if (valid_lft != 0 && valid_lft < in6_dev->cnf.accept_ra_min_lft)
2761 		goto put;
2762 
2763 	/*
2764 	 *	Two things going on here:
2765 	 *	1) Add routes for on-link prefixes
2766 	 *	2) Configure prefixes with the auto flag set
2767 	 */
2768 
2769 	if (pinfo->onlink) {
2770 		struct fib6_info *rt;
2771 		unsigned long rt_expires;
2772 
2773 		/* Avoid arithmetic overflow. Really, we could
2774 		 * save rt_expires in seconds, likely valid_lft,
2775 		 * but it would require division in fib gc, that it
2776 		 * not good.
2777 		 */
2778 		if (HZ > USER_HZ)
2779 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2780 		else
2781 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2782 
2783 		if (addrconf_finite_timeout(rt_expires))
2784 			rt_expires *= HZ;
2785 
2786 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2787 					       pinfo->prefix_len,
2788 					       dev,
2789 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2790 					       RTF_DEFAULT, true);
2791 
2792 		if (rt) {
2793 			/* Autoconf prefix route */
2794 			if (valid_lft == 0) {
2795 				ip6_del_rt(net, rt, false);
2796 				rt = NULL;
2797 			} else if (addrconf_finite_timeout(rt_expires)) {
2798 				/* not infinity */
2799 				fib6_set_expires(rt, jiffies + rt_expires);
2800 			} else {
2801 				fib6_clean_expires(rt);
2802 			}
2803 		} else if (valid_lft) {
2804 			clock_t expires = 0;
2805 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2806 			if (addrconf_finite_timeout(rt_expires)) {
2807 				/* not infinity */
2808 				flags |= RTF_EXPIRES;
2809 				expires = jiffies_to_clock_t(rt_expires);
2810 			}
2811 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2812 					      0, dev, expires, flags,
2813 					      GFP_ATOMIC);
2814 		}
2815 		fib6_info_release(rt);
2816 	}
2817 
2818 	/* Try to figure out our local address for this prefix */
2819 
2820 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2821 		struct in6_addr addr;
2822 		bool tokenized = false, dev_addr_generated = false;
2823 
2824 		if (pinfo->prefix_len == 64) {
2825 			memcpy(&addr, &pinfo->prefix, 8);
2826 
2827 			if (!ipv6_addr_any(&in6_dev->token)) {
2828 				read_lock_bh(&in6_dev->lock);
2829 				memcpy(addr.s6_addr + 8,
2830 				       in6_dev->token.s6_addr + 8, 8);
2831 				read_unlock_bh(&in6_dev->lock);
2832 				tokenized = true;
2833 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2834 				   !ipv6_generate_stable_address(&addr, 0,
2835 								 in6_dev)) {
2836 				addr_flags |= IFA_F_STABLE_PRIVACY;
2837 				goto ok;
2838 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2839 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2840 				goto put;
2841 			} else {
2842 				dev_addr_generated = true;
2843 			}
2844 			goto ok;
2845 		}
2846 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2847 				    pinfo->prefix_len);
2848 		goto put;
2849 
2850 ok:
2851 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2852 						   &addr, addr_type,
2853 						   addr_flags, sllao,
2854 						   tokenized, valid_lft,
2855 						   prefered_lft);
2856 		if (err)
2857 			goto put;
2858 
2859 		/* Ignore error case here because previous prefix add addr was
2860 		 * successful which will be notified.
2861 		 */
2862 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2863 					      addr_type, addr_flags, sllao,
2864 					      tokenized, valid_lft,
2865 					      prefered_lft,
2866 					      dev_addr_generated);
2867 	}
2868 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2869 put:
2870 	in6_dev_put(in6_dev);
2871 }
2872 
2873 static int addrconf_set_sit_dstaddr(struct net *net, struct net_device *dev,
2874 		struct in6_ifreq *ireq)
2875 {
2876 	struct ip_tunnel_parm p = { };
2877 	int err;
2878 
2879 	if (!(ipv6_addr_type(&ireq->ifr6_addr) & IPV6_ADDR_COMPATv4))
2880 		return -EADDRNOTAVAIL;
2881 
2882 	p.iph.daddr = ireq->ifr6_addr.s6_addr32[3];
2883 	p.iph.version = 4;
2884 	p.iph.ihl = 5;
2885 	p.iph.protocol = IPPROTO_IPV6;
2886 	p.iph.ttl = 64;
2887 
2888 	if (!dev->netdev_ops->ndo_tunnel_ctl)
2889 		return -EOPNOTSUPP;
2890 	err = dev->netdev_ops->ndo_tunnel_ctl(dev, &p, SIOCADDTUNNEL);
2891 	if (err)
2892 		return err;
2893 
2894 	dev = __dev_get_by_name(net, p.name);
2895 	if (!dev)
2896 		return -ENOBUFS;
2897 	return dev_open(dev, NULL);
2898 }
2899 
2900 /*
2901  *	Set destination address.
2902  *	Special case for SIT interfaces where we create a new "virtual"
2903  *	device.
2904  */
2905 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2906 {
2907 	struct net_device *dev;
2908 	struct in6_ifreq ireq;
2909 	int err = -ENODEV;
2910 
2911 	if (!IS_ENABLED(CONFIG_IPV6_SIT))
2912 		return -ENODEV;
2913 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2914 		return -EFAULT;
2915 
2916 	rtnl_lock();
2917 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2918 	if (dev && dev->type == ARPHRD_SIT)
2919 		err = addrconf_set_sit_dstaddr(net, dev, &ireq);
2920 	rtnl_unlock();
2921 	return err;
2922 }
2923 
2924 static int ipv6_mc_config(struct sock *sk, bool join,
2925 			  const struct in6_addr *addr, int ifindex)
2926 {
2927 	int ret;
2928 
2929 	ASSERT_RTNL();
2930 
2931 	lock_sock(sk);
2932 	if (join)
2933 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2934 	else
2935 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2936 	release_sock(sk);
2937 
2938 	return ret;
2939 }
2940 
2941 /*
2942  *	Manual configuration of address on an interface
2943  */
2944 static int inet6_addr_add(struct net *net, int ifindex,
2945 			  struct ifa6_config *cfg,
2946 			  struct netlink_ext_ack *extack)
2947 {
2948 	struct inet6_ifaddr *ifp;
2949 	struct inet6_dev *idev;
2950 	struct net_device *dev;
2951 	unsigned long timeout;
2952 	clock_t expires;
2953 	u32 flags;
2954 
2955 	ASSERT_RTNL();
2956 
2957 	if (cfg->plen > 128) {
2958 		NL_SET_ERR_MSG_MOD(extack, "Invalid prefix length");
2959 		return -EINVAL;
2960 	}
2961 
2962 	/* check the lifetime */
2963 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft) {
2964 		NL_SET_ERR_MSG_MOD(extack, "address lifetime invalid");
2965 		return -EINVAL;
2966 	}
2967 
2968 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR && cfg->plen != 64) {
2969 		NL_SET_ERR_MSG_MOD(extack, "address with \"mngtmpaddr\" flag must have a prefix length of 64");
2970 		return -EINVAL;
2971 	}
2972 
2973 	dev = __dev_get_by_index(net, ifindex);
2974 	if (!dev)
2975 		return -ENODEV;
2976 
2977 	idev = addrconf_add_dev(dev);
2978 	if (IS_ERR(idev)) {
2979 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
2980 		return PTR_ERR(idev);
2981 	}
2982 
2983 	if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2984 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2985 					 true, cfg->pfx, ifindex);
2986 
2987 		if (ret < 0) {
2988 			NL_SET_ERR_MSG_MOD(extack, "Multicast auto join failed");
2989 			return ret;
2990 		}
2991 	}
2992 
2993 	cfg->scope = ipv6_addr_scope(cfg->pfx);
2994 
2995 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
2996 	if (addrconf_finite_timeout(timeout)) {
2997 		expires = jiffies_to_clock_t(timeout * HZ);
2998 		cfg->valid_lft = timeout;
2999 		flags = RTF_EXPIRES;
3000 	} else {
3001 		expires = 0;
3002 		flags = 0;
3003 		cfg->ifa_flags |= IFA_F_PERMANENT;
3004 	}
3005 
3006 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
3007 	if (addrconf_finite_timeout(timeout)) {
3008 		if (timeout == 0)
3009 			cfg->ifa_flags |= IFA_F_DEPRECATED;
3010 		cfg->preferred_lft = timeout;
3011 	}
3012 
3013 	ifp = ipv6_add_addr(idev, cfg, true, extack);
3014 	if (!IS_ERR(ifp)) {
3015 		if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
3016 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3017 					      ifp->rt_priority, dev, expires,
3018 					      flags, GFP_KERNEL);
3019 		}
3020 
3021 		/* Send a netlink notification if DAD is enabled and
3022 		 * optimistic flag is not set
3023 		 */
3024 		if (!(ifp->flags & (IFA_F_OPTIMISTIC | IFA_F_NODAD)))
3025 			ipv6_ifa_notify(0, ifp);
3026 		/*
3027 		 * Note that section 3.1 of RFC 4429 indicates
3028 		 * that the Optimistic flag should not be set for
3029 		 * manually configured addresses
3030 		 */
3031 		addrconf_dad_start(ifp);
3032 		if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR)
3033 			manage_tempaddrs(idev, ifp, cfg->valid_lft,
3034 					 cfg->preferred_lft, true, jiffies);
3035 		in6_ifa_put(ifp);
3036 		addrconf_verify_rtnl(net);
3037 		return 0;
3038 	} else if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
3039 		ipv6_mc_config(net->ipv6.mc_autojoin_sk, false,
3040 			       cfg->pfx, ifindex);
3041 	}
3042 
3043 	return PTR_ERR(ifp);
3044 }
3045 
3046 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
3047 			  const struct in6_addr *pfx, unsigned int plen,
3048 			  struct netlink_ext_ack *extack)
3049 {
3050 	struct inet6_ifaddr *ifp;
3051 	struct inet6_dev *idev;
3052 	struct net_device *dev;
3053 
3054 	if (plen > 128) {
3055 		NL_SET_ERR_MSG_MOD(extack, "Invalid prefix length");
3056 		return -EINVAL;
3057 	}
3058 
3059 	dev = __dev_get_by_index(net, ifindex);
3060 	if (!dev) {
3061 		NL_SET_ERR_MSG_MOD(extack, "Unable to find the interface");
3062 		return -ENODEV;
3063 	}
3064 
3065 	idev = __in6_dev_get(dev);
3066 	if (!idev) {
3067 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
3068 		return -ENXIO;
3069 	}
3070 
3071 	read_lock_bh(&idev->lock);
3072 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3073 		if (ifp->prefix_len == plen &&
3074 		    ipv6_addr_equal(pfx, &ifp->addr)) {
3075 			in6_ifa_hold(ifp);
3076 			read_unlock_bh(&idev->lock);
3077 
3078 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
3079 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
3080 				manage_tempaddrs(idev, ifp, 0, 0, false,
3081 						 jiffies);
3082 			ipv6_del_addr(ifp);
3083 			addrconf_verify_rtnl(net);
3084 			if (ipv6_addr_is_multicast(pfx)) {
3085 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3086 					       false, pfx, dev->ifindex);
3087 			}
3088 			return 0;
3089 		}
3090 	}
3091 	read_unlock_bh(&idev->lock);
3092 
3093 	NL_SET_ERR_MSG_MOD(extack, "address not found");
3094 	return -EADDRNOTAVAIL;
3095 }
3096 
3097 
3098 int addrconf_add_ifaddr(struct net *net, void __user *arg)
3099 {
3100 	struct ifa6_config cfg = {
3101 		.ifa_flags = IFA_F_PERMANENT,
3102 		.preferred_lft = INFINITY_LIFE_TIME,
3103 		.valid_lft = INFINITY_LIFE_TIME,
3104 	};
3105 	struct in6_ifreq ireq;
3106 	int err;
3107 
3108 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3109 		return -EPERM;
3110 
3111 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3112 		return -EFAULT;
3113 
3114 	cfg.pfx = &ireq.ifr6_addr;
3115 	cfg.plen = ireq.ifr6_prefixlen;
3116 
3117 	rtnl_lock();
3118 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &cfg, NULL);
3119 	rtnl_unlock();
3120 	return err;
3121 }
3122 
3123 int addrconf_del_ifaddr(struct net *net, void __user *arg)
3124 {
3125 	struct in6_ifreq ireq;
3126 	int err;
3127 
3128 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3129 		return -EPERM;
3130 
3131 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3132 		return -EFAULT;
3133 
3134 	rtnl_lock();
3135 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
3136 			     ireq.ifr6_prefixlen, NULL);
3137 	rtnl_unlock();
3138 	return err;
3139 }
3140 
3141 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
3142 		     int plen, int scope, u8 proto)
3143 {
3144 	struct inet6_ifaddr *ifp;
3145 	struct ifa6_config cfg = {
3146 		.pfx = addr,
3147 		.plen = plen,
3148 		.ifa_flags = IFA_F_PERMANENT,
3149 		.valid_lft = INFINITY_LIFE_TIME,
3150 		.preferred_lft = INFINITY_LIFE_TIME,
3151 		.scope = scope,
3152 		.ifa_proto = proto
3153 	};
3154 
3155 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3156 	if (!IS_ERR(ifp)) {
3157 		spin_lock_bh(&ifp->lock);
3158 		ifp->flags &= ~IFA_F_TENTATIVE;
3159 		spin_unlock_bh(&ifp->lock);
3160 		rt_genid_bump_ipv6(dev_net(idev->dev));
3161 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3162 		in6_ifa_put(ifp);
3163 	}
3164 }
3165 
3166 #if IS_ENABLED(CONFIG_IPV6_SIT) || IS_ENABLED(CONFIG_NET_IPGRE) || IS_ENABLED(CONFIG_IPV6_GRE)
3167 static void add_v4_addrs(struct inet6_dev *idev)
3168 {
3169 	struct in6_addr addr;
3170 	struct net_device *dev;
3171 	struct net *net = dev_net(idev->dev);
3172 	int scope, plen, offset = 0;
3173 	u32 pflags = 0;
3174 
3175 	ASSERT_RTNL();
3176 
3177 	memset(&addr, 0, sizeof(struct in6_addr));
3178 	/* in case of IP6GRE the dev_addr is an IPv6 and therefore we use only the last 4 bytes */
3179 	if (idev->dev->addr_len == sizeof(struct in6_addr))
3180 		offset = sizeof(struct in6_addr) - 4;
3181 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr + offset, 4);
3182 
3183 	if (!(idev->dev->flags & IFF_POINTOPOINT) && idev->dev->type == ARPHRD_SIT) {
3184 		scope = IPV6_ADDR_COMPATv4;
3185 		plen = 96;
3186 		pflags |= RTF_NONEXTHOP;
3187 	} else {
3188 		if (idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_NONE)
3189 			return;
3190 
3191 		addr.s6_addr32[0] = htonl(0xfe800000);
3192 		scope = IFA_LINK;
3193 		plen = 64;
3194 	}
3195 
3196 	if (addr.s6_addr32[3]) {
3197 		add_addr(idev, &addr, plen, scope, IFAPROT_UNSPEC);
3198 		addrconf_prefix_route(&addr, plen, 0, idev->dev, 0, pflags,
3199 				      GFP_KERNEL);
3200 		return;
3201 	}
3202 
3203 	for_each_netdev(net, dev) {
3204 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3205 		if (in_dev && (dev->flags & IFF_UP)) {
3206 			struct in_ifaddr *ifa;
3207 			int flag = scope;
3208 
3209 			in_dev_for_each_ifa_rtnl(ifa, in_dev) {
3210 				addr.s6_addr32[3] = ifa->ifa_local;
3211 
3212 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3213 					continue;
3214 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3215 					if (idev->dev->flags&IFF_POINTOPOINT)
3216 						continue;
3217 					flag |= IFA_HOST;
3218 				}
3219 
3220 				add_addr(idev, &addr, plen, flag,
3221 					 IFAPROT_UNSPEC);
3222 				addrconf_prefix_route(&addr, plen, 0, idev->dev,
3223 						      0, pflags, GFP_KERNEL);
3224 			}
3225 		}
3226 	}
3227 }
3228 #endif
3229 
3230 static void init_loopback(struct net_device *dev)
3231 {
3232 	struct inet6_dev  *idev;
3233 
3234 	/* ::1 */
3235 
3236 	ASSERT_RTNL();
3237 
3238 	idev = ipv6_find_idev(dev);
3239 	if (IS_ERR(idev)) {
3240 		pr_debug("%s: add_dev failed\n", __func__);
3241 		return;
3242 	}
3243 
3244 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST, IFAPROT_KERNEL_LO);
3245 }
3246 
3247 void addrconf_add_linklocal(struct inet6_dev *idev,
3248 			    const struct in6_addr *addr, u32 flags)
3249 {
3250 	struct ifa6_config cfg = {
3251 		.pfx = addr,
3252 		.plen = 64,
3253 		.ifa_flags = flags | IFA_F_PERMANENT,
3254 		.valid_lft = INFINITY_LIFE_TIME,
3255 		.preferred_lft = INFINITY_LIFE_TIME,
3256 		.scope = IFA_LINK,
3257 		.ifa_proto = IFAPROT_KERNEL_LL
3258 	};
3259 	struct inet6_ifaddr *ifp;
3260 
3261 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3262 	if ((dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad ||
3263 	     idev->cnf.optimistic_dad) &&
3264 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3265 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
3266 #endif
3267 
3268 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3269 	if (!IS_ERR(ifp)) {
3270 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, 0, idev->dev,
3271 				      0, 0, GFP_ATOMIC);
3272 		addrconf_dad_start(ifp);
3273 		in6_ifa_put(ifp);
3274 	}
3275 }
3276 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3277 
3278 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3279 {
3280 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3281 		return true;
3282 
3283 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3284 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3285 		return true;
3286 
3287 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3288 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3289 		return true;
3290 
3291 	return false;
3292 }
3293 
3294 static int ipv6_generate_stable_address(struct in6_addr *address,
3295 					u8 dad_count,
3296 					const struct inet6_dev *idev)
3297 {
3298 	static DEFINE_SPINLOCK(lock);
3299 	static __u32 digest[SHA1_DIGEST_WORDS];
3300 	static __u32 workspace[SHA1_WORKSPACE_WORDS];
3301 
3302 	static union {
3303 		char __data[SHA1_BLOCK_SIZE];
3304 		struct {
3305 			struct in6_addr secret;
3306 			__be32 prefix[2];
3307 			unsigned char hwaddr[MAX_ADDR_LEN];
3308 			u8 dad_count;
3309 		} __packed;
3310 	} data;
3311 
3312 	struct in6_addr secret;
3313 	struct in6_addr temp;
3314 	struct net *net = dev_net(idev->dev);
3315 
3316 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3317 
3318 	if (idev->cnf.stable_secret.initialized)
3319 		secret = idev->cnf.stable_secret.secret;
3320 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3321 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3322 	else
3323 		return -1;
3324 
3325 retry:
3326 	spin_lock_bh(&lock);
3327 
3328 	sha1_init(digest);
3329 	memset(&data, 0, sizeof(data));
3330 	memset(workspace, 0, sizeof(workspace));
3331 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3332 	data.prefix[0] = address->s6_addr32[0];
3333 	data.prefix[1] = address->s6_addr32[1];
3334 	data.secret = secret;
3335 	data.dad_count = dad_count;
3336 
3337 	sha1_transform(digest, data.__data, workspace);
3338 
3339 	temp = *address;
3340 	temp.s6_addr32[2] = (__force __be32)digest[0];
3341 	temp.s6_addr32[3] = (__force __be32)digest[1];
3342 
3343 	spin_unlock_bh(&lock);
3344 
3345 	if (ipv6_reserved_interfaceid(temp)) {
3346 		dad_count++;
3347 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3348 			return -1;
3349 		goto retry;
3350 	}
3351 
3352 	*address = temp;
3353 	return 0;
3354 }
3355 
3356 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3357 {
3358 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3359 
3360 	if (s->initialized)
3361 		return;
3362 	s = &idev->cnf.stable_secret;
3363 	get_random_bytes(&s->secret, sizeof(s->secret));
3364 	s->initialized = true;
3365 }
3366 
3367 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3368 {
3369 	struct in6_addr addr;
3370 
3371 	/* no link local addresses on L3 master devices */
3372 	if (netif_is_l3_master(idev->dev))
3373 		return;
3374 
3375 	/* no link local addresses on devices flagged as slaves */
3376 	if (idev->dev->priv_flags & IFF_NO_ADDRCONF)
3377 		return;
3378 
3379 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3380 
3381 	switch (idev->cnf.addr_gen_mode) {
3382 	case IN6_ADDR_GEN_MODE_RANDOM:
3383 		ipv6_gen_mode_random_init(idev);
3384 		fallthrough;
3385 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3386 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3387 			addrconf_add_linklocal(idev, &addr,
3388 					       IFA_F_STABLE_PRIVACY);
3389 		else if (prefix_route)
3390 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3391 					      0, 0, GFP_KERNEL);
3392 		break;
3393 	case IN6_ADDR_GEN_MODE_EUI64:
3394 		/* addrconf_add_linklocal also adds a prefix_route and we
3395 		 * only need to care about prefix routes if ipv6_generate_eui64
3396 		 * couldn't generate one.
3397 		 */
3398 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3399 			addrconf_add_linklocal(idev, &addr, 0);
3400 		else if (prefix_route)
3401 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3402 					      0, 0, GFP_KERNEL);
3403 		break;
3404 	case IN6_ADDR_GEN_MODE_NONE:
3405 	default:
3406 		/* will not add any link local address */
3407 		break;
3408 	}
3409 }
3410 
3411 static void addrconf_dev_config(struct net_device *dev)
3412 {
3413 	struct inet6_dev *idev;
3414 
3415 	ASSERT_RTNL();
3416 
3417 	if ((dev->type != ARPHRD_ETHER) &&
3418 	    (dev->type != ARPHRD_FDDI) &&
3419 	    (dev->type != ARPHRD_ARCNET) &&
3420 	    (dev->type != ARPHRD_INFINIBAND) &&
3421 	    (dev->type != ARPHRD_IEEE1394) &&
3422 	    (dev->type != ARPHRD_TUNNEL6) &&
3423 	    (dev->type != ARPHRD_6LOWPAN) &&
3424 	    (dev->type != ARPHRD_TUNNEL) &&
3425 	    (dev->type != ARPHRD_NONE) &&
3426 	    (dev->type != ARPHRD_RAWIP)) {
3427 		/* Alas, we support only Ethernet autoconfiguration. */
3428 		idev = __in6_dev_get(dev);
3429 		if (!IS_ERR_OR_NULL(idev) && dev->flags & IFF_UP &&
3430 		    dev->flags & IFF_MULTICAST)
3431 			ipv6_mc_up(idev);
3432 		return;
3433 	}
3434 
3435 	idev = addrconf_add_dev(dev);
3436 	if (IS_ERR(idev))
3437 		return;
3438 
3439 	/* this device type has no EUI support */
3440 	if (dev->type == ARPHRD_NONE &&
3441 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3442 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_RANDOM;
3443 
3444 	addrconf_addr_gen(idev, false);
3445 }
3446 
3447 #if IS_ENABLED(CONFIG_IPV6_SIT)
3448 static void addrconf_sit_config(struct net_device *dev)
3449 {
3450 	struct inet6_dev *idev;
3451 
3452 	ASSERT_RTNL();
3453 
3454 	/*
3455 	 * Configure the tunnel with one of our IPv4
3456 	 * addresses... we should configure all of
3457 	 * our v4 addrs in the tunnel
3458 	 */
3459 
3460 	idev = ipv6_find_idev(dev);
3461 	if (IS_ERR(idev)) {
3462 		pr_debug("%s: add_dev failed\n", __func__);
3463 		return;
3464 	}
3465 
3466 	if (dev->priv_flags & IFF_ISATAP) {
3467 		addrconf_addr_gen(idev, false);
3468 		return;
3469 	}
3470 
3471 	add_v4_addrs(idev);
3472 
3473 	if (dev->flags&IFF_POINTOPOINT)
3474 		addrconf_add_mroute(dev);
3475 }
3476 #endif
3477 
3478 #if IS_ENABLED(CONFIG_NET_IPGRE) || IS_ENABLED(CONFIG_IPV6_GRE)
3479 static void addrconf_gre_config(struct net_device *dev)
3480 {
3481 	struct inet6_dev *idev;
3482 
3483 	ASSERT_RTNL();
3484 
3485 	idev = ipv6_find_idev(dev);
3486 	if (IS_ERR(idev)) {
3487 		pr_debug("%s: add_dev failed\n", __func__);
3488 		return;
3489 	}
3490 
3491 	if (dev->type == ARPHRD_ETHER) {
3492 		addrconf_addr_gen(idev, true);
3493 		return;
3494 	}
3495 
3496 	add_v4_addrs(idev);
3497 
3498 	if (dev->flags & IFF_POINTOPOINT)
3499 		addrconf_add_mroute(dev);
3500 }
3501 #endif
3502 
3503 static void addrconf_init_auto_addrs(struct net_device *dev)
3504 {
3505 	switch (dev->type) {
3506 #if IS_ENABLED(CONFIG_IPV6_SIT)
3507 	case ARPHRD_SIT:
3508 		addrconf_sit_config(dev);
3509 		break;
3510 #endif
3511 #if IS_ENABLED(CONFIG_NET_IPGRE) || IS_ENABLED(CONFIG_IPV6_GRE)
3512 	case ARPHRD_IP6GRE:
3513 	case ARPHRD_IPGRE:
3514 		addrconf_gre_config(dev);
3515 		break;
3516 #endif
3517 	case ARPHRD_LOOPBACK:
3518 		init_loopback(dev);
3519 		break;
3520 
3521 	default:
3522 		addrconf_dev_config(dev);
3523 		break;
3524 	}
3525 }
3526 
3527 static int fixup_permanent_addr(struct net *net,
3528 				struct inet6_dev *idev,
3529 				struct inet6_ifaddr *ifp)
3530 {
3531 	/* !fib6_node means the host route was removed from the
3532 	 * FIB, for example, if 'lo' device is taken down. In that
3533 	 * case regenerate the host route.
3534 	 */
3535 	if (!ifp->rt || !ifp->rt->fib6_node) {
3536 		struct fib6_info *f6i, *prev;
3537 
3538 		f6i = addrconf_f6i_alloc(net, idev, &ifp->addr, false,
3539 					 GFP_ATOMIC, NULL);
3540 		if (IS_ERR(f6i))
3541 			return PTR_ERR(f6i);
3542 
3543 		/* ifp->rt can be accessed outside of rtnl */
3544 		spin_lock(&ifp->lock);
3545 		prev = ifp->rt;
3546 		ifp->rt = f6i;
3547 		spin_unlock(&ifp->lock);
3548 
3549 		fib6_info_release(prev);
3550 	}
3551 
3552 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3553 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3554 				      ifp->rt_priority, idev->dev, 0, 0,
3555 				      GFP_ATOMIC);
3556 	}
3557 
3558 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3559 		addrconf_dad_start(ifp);
3560 
3561 	return 0;
3562 }
3563 
3564 static void addrconf_permanent_addr(struct net *net, struct net_device *dev)
3565 {
3566 	struct inet6_ifaddr *ifp, *tmp;
3567 	struct inet6_dev *idev;
3568 
3569 	idev = __in6_dev_get(dev);
3570 	if (!idev)
3571 		return;
3572 
3573 	write_lock_bh(&idev->lock);
3574 
3575 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3576 		if ((ifp->flags & IFA_F_PERMANENT) &&
3577 		    fixup_permanent_addr(net, idev, ifp) < 0) {
3578 			write_unlock_bh(&idev->lock);
3579 			in6_ifa_hold(ifp);
3580 			ipv6_del_addr(ifp);
3581 			write_lock_bh(&idev->lock);
3582 
3583 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3584 					     idev->dev->name, &ifp->addr);
3585 		}
3586 	}
3587 
3588 	write_unlock_bh(&idev->lock);
3589 }
3590 
3591 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3592 			   void *ptr)
3593 {
3594 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3595 	struct netdev_notifier_change_info *change_info;
3596 	struct netdev_notifier_changeupper_info *info;
3597 	struct inet6_dev *idev = __in6_dev_get(dev);
3598 	struct net *net = dev_net(dev);
3599 	int run_pending = 0;
3600 	int err;
3601 
3602 	switch (event) {
3603 	case NETDEV_REGISTER:
3604 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3605 			idev = ipv6_add_dev(dev);
3606 			if (IS_ERR(idev))
3607 				return notifier_from_errno(PTR_ERR(idev));
3608 		}
3609 		break;
3610 
3611 	case NETDEV_CHANGEMTU:
3612 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3613 		if (dev->mtu < IPV6_MIN_MTU) {
3614 			addrconf_ifdown(dev, dev != net->loopback_dev);
3615 			break;
3616 		}
3617 
3618 		if (idev) {
3619 			rt6_mtu_change(dev, dev->mtu);
3620 			idev->cnf.mtu6 = dev->mtu;
3621 			break;
3622 		}
3623 
3624 		/* allocate new idev */
3625 		idev = ipv6_add_dev(dev);
3626 		if (IS_ERR(idev))
3627 			break;
3628 
3629 		/* device is still not ready */
3630 		if (!(idev->if_flags & IF_READY))
3631 			break;
3632 
3633 		run_pending = 1;
3634 		fallthrough;
3635 	case NETDEV_UP:
3636 	case NETDEV_CHANGE:
3637 		if (idev && idev->cnf.disable_ipv6)
3638 			break;
3639 
3640 		if (dev->priv_flags & IFF_NO_ADDRCONF) {
3641 			if (event == NETDEV_UP && !IS_ERR_OR_NULL(idev) &&
3642 			    dev->flags & IFF_UP && dev->flags & IFF_MULTICAST)
3643 				ipv6_mc_up(idev);
3644 			break;
3645 		}
3646 
3647 		if (event == NETDEV_UP) {
3648 			/* restore routes for permanent addresses */
3649 			addrconf_permanent_addr(net, dev);
3650 
3651 			if (!addrconf_link_ready(dev)) {
3652 				/* device is not ready yet. */
3653 				pr_debug("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3654 					 dev->name);
3655 				break;
3656 			}
3657 
3658 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3659 				idev = ipv6_add_dev(dev);
3660 
3661 			if (!IS_ERR_OR_NULL(idev)) {
3662 				idev->if_flags |= IF_READY;
3663 				run_pending = 1;
3664 			}
3665 		} else if (event == NETDEV_CHANGE) {
3666 			if (!addrconf_link_ready(dev)) {
3667 				/* device is still not ready. */
3668 				rt6_sync_down_dev(dev, event);
3669 				break;
3670 			}
3671 
3672 			if (!IS_ERR_OR_NULL(idev)) {
3673 				if (idev->if_flags & IF_READY) {
3674 					/* device is already configured -
3675 					 * but resend MLD reports, we might
3676 					 * have roamed and need to update
3677 					 * multicast snooping switches
3678 					 */
3679 					ipv6_mc_up(idev);
3680 					change_info = ptr;
3681 					if (change_info->flags_changed & IFF_NOARP)
3682 						addrconf_dad_run(idev, true);
3683 					rt6_sync_up(dev, RTNH_F_LINKDOWN);
3684 					break;
3685 				}
3686 				idev->if_flags |= IF_READY;
3687 			}
3688 
3689 			pr_debug("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3690 				 dev->name);
3691 
3692 			run_pending = 1;
3693 		}
3694 
3695 		addrconf_init_auto_addrs(dev);
3696 
3697 		if (!IS_ERR_OR_NULL(idev)) {
3698 			if (run_pending)
3699 				addrconf_dad_run(idev, false);
3700 
3701 			/* Device has an address by now */
3702 			rt6_sync_up(dev, RTNH_F_DEAD);
3703 
3704 			/*
3705 			 * If the MTU changed during the interface down,
3706 			 * when the interface up, the changed MTU must be
3707 			 * reflected in the idev as well as routers.
3708 			 */
3709 			if (idev->cnf.mtu6 != dev->mtu &&
3710 			    dev->mtu >= IPV6_MIN_MTU) {
3711 				rt6_mtu_change(dev, dev->mtu);
3712 				idev->cnf.mtu6 = dev->mtu;
3713 			}
3714 			idev->tstamp = jiffies;
3715 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3716 
3717 			/*
3718 			 * If the changed mtu during down is lower than
3719 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3720 			 */
3721 			if (dev->mtu < IPV6_MIN_MTU)
3722 				addrconf_ifdown(dev, dev != net->loopback_dev);
3723 		}
3724 		break;
3725 
3726 	case NETDEV_DOWN:
3727 	case NETDEV_UNREGISTER:
3728 		/*
3729 		 *	Remove all addresses from this interface.
3730 		 */
3731 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3732 		break;
3733 
3734 	case NETDEV_CHANGENAME:
3735 		if (idev) {
3736 			snmp6_unregister_dev(idev);
3737 			addrconf_sysctl_unregister(idev);
3738 			err = addrconf_sysctl_register(idev);
3739 			if (err)
3740 				return notifier_from_errno(err);
3741 			err = snmp6_register_dev(idev);
3742 			if (err) {
3743 				addrconf_sysctl_unregister(idev);
3744 				return notifier_from_errno(err);
3745 			}
3746 		}
3747 		break;
3748 
3749 	case NETDEV_PRE_TYPE_CHANGE:
3750 	case NETDEV_POST_TYPE_CHANGE:
3751 		if (idev)
3752 			addrconf_type_change(dev, event);
3753 		break;
3754 
3755 	case NETDEV_CHANGEUPPER:
3756 		info = ptr;
3757 
3758 		/* flush all routes if dev is linked to or unlinked from
3759 		 * an L3 master device (e.g., VRF)
3760 		 */
3761 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3762 			addrconf_ifdown(dev, false);
3763 	}
3764 
3765 	return NOTIFY_OK;
3766 }
3767 
3768 /*
3769  *	addrconf module should be notified of a device going up
3770  */
3771 static struct notifier_block ipv6_dev_notf = {
3772 	.notifier_call = addrconf_notify,
3773 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3774 };
3775 
3776 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3777 {
3778 	struct inet6_dev *idev;
3779 	ASSERT_RTNL();
3780 
3781 	idev = __in6_dev_get(dev);
3782 
3783 	if (event == NETDEV_POST_TYPE_CHANGE)
3784 		ipv6_mc_remap(idev);
3785 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3786 		ipv6_mc_unmap(idev);
3787 }
3788 
3789 static bool addr_is_local(const struct in6_addr *addr)
3790 {
3791 	return ipv6_addr_type(addr) &
3792 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3793 }
3794 
3795 static int addrconf_ifdown(struct net_device *dev, bool unregister)
3796 {
3797 	unsigned long event = unregister ? NETDEV_UNREGISTER : NETDEV_DOWN;
3798 	struct net *net = dev_net(dev);
3799 	struct inet6_dev *idev;
3800 	struct inet6_ifaddr *ifa;
3801 	LIST_HEAD(tmp_addr_list);
3802 	bool keep_addr = false;
3803 	bool was_ready;
3804 	int state, i;
3805 
3806 	ASSERT_RTNL();
3807 
3808 	rt6_disable_ip(dev, event);
3809 
3810 	idev = __in6_dev_get(dev);
3811 	if (!idev)
3812 		return -ENODEV;
3813 
3814 	/*
3815 	 * Step 1: remove reference to ipv6 device from parent device.
3816 	 *	   Do not dev_put!
3817 	 */
3818 	if (unregister) {
3819 		idev->dead = 1;
3820 
3821 		/* protected by rtnl_lock */
3822 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3823 
3824 		/* Step 1.5: remove snmp6 entry */
3825 		snmp6_unregister_dev(idev);
3826 
3827 	}
3828 
3829 	/* combine the user config with event to determine if permanent
3830 	 * addresses are to be removed from address hash table
3831 	 */
3832 	if (!unregister && !idev->cnf.disable_ipv6) {
3833 		/* aggregate the system setting and interface setting */
3834 		int _keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
3835 
3836 		if (!_keep_addr)
3837 			_keep_addr = idev->cnf.keep_addr_on_down;
3838 
3839 		keep_addr = (_keep_addr > 0);
3840 	}
3841 
3842 	/* Step 2: clear hash table */
3843 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3844 		struct hlist_head *h = &net->ipv6.inet6_addr_lst[i];
3845 
3846 		spin_lock_bh(&net->ipv6.addrconf_hash_lock);
3847 restart:
3848 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3849 			if (ifa->idev == idev) {
3850 				addrconf_del_dad_work(ifa);
3851 				/* combined flag + permanent flag decide if
3852 				 * address is retained on a down event
3853 				 */
3854 				if (!keep_addr ||
3855 				    !(ifa->flags & IFA_F_PERMANENT) ||
3856 				    addr_is_local(&ifa->addr)) {
3857 					hlist_del_init_rcu(&ifa->addr_lst);
3858 					goto restart;
3859 				}
3860 			}
3861 		}
3862 		spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
3863 	}
3864 
3865 	write_lock_bh(&idev->lock);
3866 
3867 	addrconf_del_rs_timer(idev);
3868 
3869 	/* Step 2: clear flags for stateless addrconf, repeated down
3870 	 *         detection
3871 	 */
3872 	was_ready = idev->if_flags & IF_READY;
3873 	if (!unregister)
3874 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3875 
3876 	/* Step 3: clear tempaddr list */
3877 	while (!list_empty(&idev->tempaddr_list)) {
3878 		ifa = list_first_entry(&idev->tempaddr_list,
3879 				       struct inet6_ifaddr, tmp_list);
3880 		list_del(&ifa->tmp_list);
3881 		write_unlock_bh(&idev->lock);
3882 		spin_lock_bh(&ifa->lock);
3883 
3884 		if (ifa->ifpub) {
3885 			in6_ifa_put(ifa->ifpub);
3886 			ifa->ifpub = NULL;
3887 		}
3888 		spin_unlock_bh(&ifa->lock);
3889 		in6_ifa_put(ifa);
3890 		write_lock_bh(&idev->lock);
3891 	}
3892 
3893 	list_for_each_entry(ifa, &idev->addr_list, if_list)
3894 		list_add_tail(&ifa->if_list_aux, &tmp_addr_list);
3895 	write_unlock_bh(&idev->lock);
3896 
3897 	while (!list_empty(&tmp_addr_list)) {
3898 		struct fib6_info *rt = NULL;
3899 		bool keep;
3900 
3901 		ifa = list_first_entry(&tmp_addr_list,
3902 				       struct inet6_ifaddr, if_list_aux);
3903 		list_del(&ifa->if_list_aux);
3904 
3905 		addrconf_del_dad_work(ifa);
3906 
3907 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3908 			!addr_is_local(&ifa->addr);
3909 
3910 		spin_lock_bh(&ifa->lock);
3911 
3912 		if (keep) {
3913 			/* set state to skip the notifier below */
3914 			state = INET6_IFADDR_STATE_DEAD;
3915 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3916 			if (!(ifa->flags & IFA_F_NODAD))
3917 				ifa->flags |= IFA_F_TENTATIVE;
3918 
3919 			rt = ifa->rt;
3920 			ifa->rt = NULL;
3921 		} else {
3922 			state = ifa->state;
3923 			ifa->state = INET6_IFADDR_STATE_DEAD;
3924 		}
3925 
3926 		spin_unlock_bh(&ifa->lock);
3927 
3928 		if (rt)
3929 			ip6_del_rt(net, rt, false);
3930 
3931 		if (state != INET6_IFADDR_STATE_DEAD) {
3932 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3933 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3934 		} else {
3935 			if (idev->cnf.forwarding)
3936 				addrconf_leave_anycast(ifa);
3937 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3938 		}
3939 
3940 		if (!keep) {
3941 			write_lock_bh(&idev->lock);
3942 			list_del_rcu(&ifa->if_list);
3943 			write_unlock_bh(&idev->lock);
3944 			in6_ifa_put(ifa);
3945 		}
3946 	}
3947 
3948 	/* Step 5: Discard anycast and multicast list */
3949 	if (unregister) {
3950 		ipv6_ac_destroy_dev(idev);
3951 		ipv6_mc_destroy_dev(idev);
3952 	} else if (was_ready) {
3953 		ipv6_mc_down(idev);
3954 	}
3955 
3956 	idev->tstamp = jiffies;
3957 	idev->ra_mtu = 0;
3958 
3959 	/* Last: Shot the device (if unregistered) */
3960 	if (unregister) {
3961 		addrconf_sysctl_unregister(idev);
3962 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3963 		neigh_ifdown(&nd_tbl, dev);
3964 		in6_dev_put(idev);
3965 	}
3966 	return 0;
3967 }
3968 
3969 static void addrconf_rs_timer(struct timer_list *t)
3970 {
3971 	struct inet6_dev *idev = from_timer(idev, t, rs_timer);
3972 	struct net_device *dev = idev->dev;
3973 	struct in6_addr lladdr;
3974 
3975 	write_lock(&idev->lock);
3976 	if (idev->dead || !(idev->if_flags & IF_READY))
3977 		goto out;
3978 
3979 	if (!ipv6_accept_ra(idev))
3980 		goto out;
3981 
3982 	/* Announcement received after solicitation was sent */
3983 	if (idev->if_flags & IF_RA_RCVD)
3984 		goto out;
3985 
3986 	if (idev->rs_probes++ < idev->cnf.rtr_solicits || idev->cnf.rtr_solicits < 0) {
3987 		write_unlock(&idev->lock);
3988 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3989 			ndisc_send_rs(dev, &lladdr,
3990 				      &in6addr_linklocal_allrouters);
3991 		else
3992 			goto put;
3993 
3994 		write_lock(&idev->lock);
3995 		idev->rs_interval = rfc3315_s14_backoff_update(
3996 			idev->rs_interval, idev->cnf.rtr_solicit_max_interval);
3997 		/* The wait after the last probe can be shorter */
3998 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3999 					     idev->cnf.rtr_solicits) ?
4000 				      idev->cnf.rtr_solicit_delay :
4001 				      idev->rs_interval);
4002 	} else {
4003 		/*
4004 		 * Note: we do not support deprecated "all on-link"
4005 		 * assumption any longer.
4006 		 */
4007 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
4008 	}
4009 
4010 out:
4011 	write_unlock(&idev->lock);
4012 put:
4013 	in6_dev_put(idev);
4014 }
4015 
4016 /*
4017  *	Duplicate Address Detection
4018  */
4019 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
4020 {
4021 	unsigned long rand_num;
4022 	struct inet6_dev *idev = ifp->idev;
4023 	u64 nonce;
4024 
4025 	if (ifp->flags & IFA_F_OPTIMISTIC)
4026 		rand_num = 0;
4027 	else
4028 		rand_num = get_random_u32_below(idev->cnf.rtr_solicit_delay ? : 1);
4029 
4030 	nonce = 0;
4031 	if (idev->cnf.enhanced_dad ||
4032 	    dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad) {
4033 		do
4034 			get_random_bytes(&nonce, 6);
4035 		while (nonce == 0);
4036 	}
4037 	ifp->dad_nonce = nonce;
4038 	ifp->dad_probes = idev->cnf.dad_transmits;
4039 	addrconf_mod_dad_work(ifp, rand_num);
4040 }
4041 
4042 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
4043 {
4044 	struct inet6_dev *idev = ifp->idev;
4045 	struct net_device *dev = idev->dev;
4046 	bool bump_id, notify = false;
4047 	struct net *net;
4048 
4049 	addrconf_join_solict(dev, &ifp->addr);
4050 
4051 	read_lock_bh(&idev->lock);
4052 	spin_lock(&ifp->lock);
4053 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
4054 		goto out;
4055 
4056 	net = dev_net(dev);
4057 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
4058 	    (net->ipv6.devconf_all->accept_dad < 1 &&
4059 	     idev->cnf.accept_dad < 1) ||
4060 	    !(ifp->flags&IFA_F_TENTATIVE) ||
4061 	    ifp->flags & IFA_F_NODAD) {
4062 		bool send_na = false;
4063 
4064 		if (ifp->flags & IFA_F_TENTATIVE &&
4065 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4066 			send_na = true;
4067 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4068 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4069 		spin_unlock(&ifp->lock);
4070 		read_unlock_bh(&idev->lock);
4071 
4072 		addrconf_dad_completed(ifp, bump_id, send_na);
4073 		return;
4074 	}
4075 
4076 	if (!(idev->if_flags & IF_READY)) {
4077 		spin_unlock(&ifp->lock);
4078 		read_unlock_bh(&idev->lock);
4079 		/*
4080 		 * If the device is not ready:
4081 		 * - keep it tentative if it is a permanent address.
4082 		 * - otherwise, kill it.
4083 		 */
4084 		in6_ifa_hold(ifp);
4085 		addrconf_dad_stop(ifp, 0);
4086 		return;
4087 	}
4088 
4089 	/*
4090 	 * Optimistic nodes can start receiving
4091 	 * Frames right away
4092 	 */
4093 	if (ifp->flags & IFA_F_OPTIMISTIC) {
4094 		ip6_ins_rt(net, ifp->rt);
4095 		if (ipv6_use_optimistic_addr(net, idev)) {
4096 			/* Because optimistic nodes can use this address,
4097 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
4098 			 */
4099 			notify = true;
4100 		}
4101 	}
4102 
4103 	addrconf_dad_kick(ifp);
4104 out:
4105 	spin_unlock(&ifp->lock);
4106 	read_unlock_bh(&idev->lock);
4107 	if (notify)
4108 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
4109 }
4110 
4111 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
4112 {
4113 	bool begin_dad = false;
4114 
4115 	spin_lock_bh(&ifp->lock);
4116 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
4117 		ifp->state = INET6_IFADDR_STATE_PREDAD;
4118 		begin_dad = true;
4119 	}
4120 	spin_unlock_bh(&ifp->lock);
4121 
4122 	if (begin_dad)
4123 		addrconf_mod_dad_work(ifp, 0);
4124 }
4125 
4126 static void addrconf_dad_work(struct work_struct *w)
4127 {
4128 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
4129 						struct inet6_ifaddr,
4130 						dad_work);
4131 	struct inet6_dev *idev = ifp->idev;
4132 	bool bump_id, disable_ipv6 = false;
4133 	struct in6_addr mcaddr;
4134 
4135 	enum {
4136 		DAD_PROCESS,
4137 		DAD_BEGIN,
4138 		DAD_ABORT,
4139 	} action = DAD_PROCESS;
4140 
4141 	rtnl_lock();
4142 
4143 	spin_lock_bh(&ifp->lock);
4144 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
4145 		action = DAD_BEGIN;
4146 		ifp->state = INET6_IFADDR_STATE_DAD;
4147 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
4148 		action = DAD_ABORT;
4149 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
4150 
4151 		if ((dev_net(idev->dev)->ipv6.devconf_all->accept_dad > 1 ||
4152 		     idev->cnf.accept_dad > 1) &&
4153 		    !idev->cnf.disable_ipv6 &&
4154 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
4155 			struct in6_addr addr;
4156 
4157 			addr.s6_addr32[0] = htonl(0xfe800000);
4158 			addr.s6_addr32[1] = 0;
4159 
4160 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
4161 			    ipv6_addr_equal(&ifp->addr, &addr)) {
4162 				/* DAD failed for link-local based on MAC */
4163 				WRITE_ONCE(idev->cnf.disable_ipv6, 1);
4164 
4165 				pr_info("%s: IPv6 being disabled!\n",
4166 					ifp->idev->dev->name);
4167 				disable_ipv6 = true;
4168 			}
4169 		}
4170 	}
4171 	spin_unlock_bh(&ifp->lock);
4172 
4173 	if (action == DAD_BEGIN) {
4174 		addrconf_dad_begin(ifp);
4175 		goto out;
4176 	} else if (action == DAD_ABORT) {
4177 		in6_ifa_hold(ifp);
4178 		addrconf_dad_stop(ifp, 1);
4179 		if (disable_ipv6)
4180 			addrconf_ifdown(idev->dev, false);
4181 		goto out;
4182 	}
4183 
4184 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
4185 		goto out;
4186 
4187 	write_lock_bh(&idev->lock);
4188 	if (idev->dead || !(idev->if_flags & IF_READY)) {
4189 		write_unlock_bh(&idev->lock);
4190 		goto out;
4191 	}
4192 
4193 	spin_lock(&ifp->lock);
4194 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
4195 		spin_unlock(&ifp->lock);
4196 		write_unlock_bh(&idev->lock);
4197 		goto out;
4198 	}
4199 
4200 	if (ifp->dad_probes == 0) {
4201 		bool send_na = false;
4202 
4203 		/*
4204 		 * DAD was successful
4205 		 */
4206 
4207 		if (ifp->flags & IFA_F_TENTATIVE &&
4208 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4209 			send_na = true;
4210 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4211 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4212 		spin_unlock(&ifp->lock);
4213 		write_unlock_bh(&idev->lock);
4214 
4215 		addrconf_dad_completed(ifp, bump_id, send_na);
4216 
4217 		goto out;
4218 	}
4219 
4220 	ifp->dad_probes--;
4221 	addrconf_mod_dad_work(ifp,
4222 			      max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME),
4223 				  HZ/100));
4224 	spin_unlock(&ifp->lock);
4225 	write_unlock_bh(&idev->lock);
4226 
4227 	/* send a neighbour solicitation for our addr */
4228 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4229 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4230 		      ifp->dad_nonce);
4231 out:
4232 	in6_ifa_put(ifp);
4233 	rtnl_unlock();
4234 }
4235 
4236 /* ifp->idev must be at least read locked */
4237 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4238 {
4239 	struct inet6_ifaddr *ifpiter;
4240 	struct inet6_dev *idev = ifp->idev;
4241 
4242 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4243 		if (ifpiter->scope > IFA_LINK)
4244 			break;
4245 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4246 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4247 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4248 		    IFA_F_PERMANENT)
4249 			return false;
4250 	}
4251 	return true;
4252 }
4253 
4254 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
4255 				   bool send_na)
4256 {
4257 	struct net_device *dev = ifp->idev->dev;
4258 	struct in6_addr lladdr;
4259 	bool send_rs, send_mld;
4260 
4261 	addrconf_del_dad_work(ifp);
4262 
4263 	/*
4264 	 *	Configure the address for reception. Now it is valid.
4265 	 */
4266 
4267 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4268 
4269 	/* If added prefix is link local and we are prepared to process
4270 	   router advertisements, start sending router solicitations.
4271 	 */
4272 
4273 	read_lock_bh(&ifp->idev->lock);
4274 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4275 	send_rs = send_mld &&
4276 		  ipv6_accept_ra(ifp->idev) &&
4277 		  ifp->idev->cnf.rtr_solicits != 0 &&
4278 		  (dev->flags & IFF_LOOPBACK) == 0 &&
4279 		  (dev->type != ARPHRD_TUNNEL) &&
4280 		  !netif_is_team_port(dev);
4281 	read_unlock_bh(&ifp->idev->lock);
4282 
4283 	/* While dad is in progress mld report's source address is in6_addrany.
4284 	 * Resend with proper ll now.
4285 	 */
4286 	if (send_mld)
4287 		ipv6_mc_dad_complete(ifp->idev);
4288 
4289 	/* send unsolicited NA if enabled */
4290 	if (send_na &&
4291 	    (ifp->idev->cnf.ndisc_notify ||
4292 	     dev_net(dev)->ipv6.devconf_all->ndisc_notify)) {
4293 		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifp->addr,
4294 			      /*router=*/ !!ifp->idev->cnf.forwarding,
4295 			      /*solicited=*/ false, /*override=*/ true,
4296 			      /*inc_opt=*/ true);
4297 	}
4298 
4299 	if (send_rs) {
4300 		/*
4301 		 *	If a host as already performed a random delay
4302 		 *	[...] as part of DAD [...] there is no need
4303 		 *	to delay again before sending the first RS
4304 		 */
4305 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4306 			return;
4307 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4308 
4309 		write_lock_bh(&ifp->idev->lock);
4310 		spin_lock(&ifp->lock);
4311 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4312 			ifp->idev->cnf.rtr_solicit_interval);
4313 		ifp->idev->rs_probes = 1;
4314 		ifp->idev->if_flags |= IF_RS_SENT;
4315 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4316 		spin_unlock(&ifp->lock);
4317 		write_unlock_bh(&ifp->idev->lock);
4318 	}
4319 
4320 	if (bump_id)
4321 		rt_genid_bump_ipv6(dev_net(dev));
4322 
4323 	/* Make sure that a new temporary address will be created
4324 	 * before this temporary address becomes deprecated.
4325 	 */
4326 	if (ifp->flags & IFA_F_TEMPORARY)
4327 		addrconf_verify_rtnl(dev_net(dev));
4328 }
4329 
4330 static void addrconf_dad_run(struct inet6_dev *idev, bool restart)
4331 {
4332 	struct inet6_ifaddr *ifp;
4333 
4334 	read_lock_bh(&idev->lock);
4335 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4336 		spin_lock(&ifp->lock);
4337 		if ((ifp->flags & IFA_F_TENTATIVE &&
4338 		     ifp->state == INET6_IFADDR_STATE_DAD) || restart) {
4339 			if (restart)
4340 				ifp->state = INET6_IFADDR_STATE_PREDAD;
4341 			addrconf_dad_kick(ifp);
4342 		}
4343 		spin_unlock(&ifp->lock);
4344 	}
4345 	read_unlock_bh(&idev->lock);
4346 }
4347 
4348 #ifdef CONFIG_PROC_FS
4349 struct if6_iter_state {
4350 	struct seq_net_private p;
4351 	int bucket;
4352 	int offset;
4353 };
4354 
4355 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4356 {
4357 	struct if6_iter_state *state = seq->private;
4358 	struct net *net = seq_file_net(seq);
4359 	struct inet6_ifaddr *ifa = NULL;
4360 	int p = 0;
4361 
4362 	/* initial bucket if pos is 0 */
4363 	if (pos == 0) {
4364 		state->bucket = 0;
4365 		state->offset = 0;
4366 	}
4367 
4368 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4369 		hlist_for_each_entry_rcu(ifa, &net->ipv6.inet6_addr_lst[state->bucket],
4370 					 addr_lst) {
4371 			/* sync with offset */
4372 			if (p < state->offset) {
4373 				p++;
4374 				continue;
4375 			}
4376 			return ifa;
4377 		}
4378 
4379 		/* prepare for next bucket */
4380 		state->offset = 0;
4381 		p = 0;
4382 	}
4383 	return NULL;
4384 }
4385 
4386 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4387 					 struct inet6_ifaddr *ifa)
4388 {
4389 	struct if6_iter_state *state = seq->private;
4390 	struct net *net = seq_file_net(seq);
4391 
4392 	hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4393 		state->offset++;
4394 		return ifa;
4395 	}
4396 
4397 	state->offset = 0;
4398 	while (++state->bucket < IN6_ADDR_HSIZE) {
4399 		hlist_for_each_entry_rcu(ifa,
4400 				     &net->ipv6.inet6_addr_lst[state->bucket], addr_lst) {
4401 			return ifa;
4402 		}
4403 	}
4404 
4405 	return NULL;
4406 }
4407 
4408 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4409 	__acquires(rcu)
4410 {
4411 	rcu_read_lock();
4412 	return if6_get_first(seq, *pos);
4413 }
4414 
4415 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4416 {
4417 	struct inet6_ifaddr *ifa;
4418 
4419 	ifa = if6_get_next(seq, v);
4420 	++*pos;
4421 	return ifa;
4422 }
4423 
4424 static void if6_seq_stop(struct seq_file *seq, void *v)
4425 	__releases(rcu)
4426 {
4427 	rcu_read_unlock();
4428 }
4429 
4430 static int if6_seq_show(struct seq_file *seq, void *v)
4431 {
4432 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4433 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4434 		   &ifp->addr,
4435 		   ifp->idev->dev->ifindex,
4436 		   ifp->prefix_len,
4437 		   ifp->scope,
4438 		   (u8) ifp->flags,
4439 		   ifp->idev->dev->name);
4440 	return 0;
4441 }
4442 
4443 static const struct seq_operations if6_seq_ops = {
4444 	.start	= if6_seq_start,
4445 	.next	= if6_seq_next,
4446 	.show	= if6_seq_show,
4447 	.stop	= if6_seq_stop,
4448 };
4449 
4450 static int __net_init if6_proc_net_init(struct net *net)
4451 {
4452 	if (!proc_create_net("if_inet6", 0444, net->proc_net, &if6_seq_ops,
4453 			sizeof(struct if6_iter_state)))
4454 		return -ENOMEM;
4455 	return 0;
4456 }
4457 
4458 static void __net_exit if6_proc_net_exit(struct net *net)
4459 {
4460 	remove_proc_entry("if_inet6", net->proc_net);
4461 }
4462 
4463 static struct pernet_operations if6_proc_net_ops = {
4464 	.init = if6_proc_net_init,
4465 	.exit = if6_proc_net_exit,
4466 };
4467 
4468 int __init if6_proc_init(void)
4469 {
4470 	return register_pernet_subsys(&if6_proc_net_ops);
4471 }
4472 
4473 void if6_proc_exit(void)
4474 {
4475 	unregister_pernet_subsys(&if6_proc_net_ops);
4476 }
4477 #endif	/* CONFIG_PROC_FS */
4478 
4479 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4480 /* Check if address is a home address configured on any interface. */
4481 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4482 {
4483 	unsigned int hash = inet6_addr_hash(net, addr);
4484 	struct inet6_ifaddr *ifp = NULL;
4485 	int ret = 0;
4486 
4487 	rcu_read_lock();
4488 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
4489 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4490 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4491 			ret = 1;
4492 			break;
4493 		}
4494 	}
4495 	rcu_read_unlock();
4496 	return ret;
4497 }
4498 #endif
4499 
4500 /* RFC6554 has some algorithm to avoid loops in segment routing by
4501  * checking if the segments contains any of a local interface address.
4502  *
4503  * Quote:
4504  *
4505  * To detect loops in the SRH, a router MUST determine if the SRH
4506  * includes multiple addresses assigned to any interface on that router.
4507  * If such addresses appear more than once and are separated by at least
4508  * one address not assigned to that router.
4509  */
4510 int ipv6_chk_rpl_srh_loop(struct net *net, const struct in6_addr *segs,
4511 			  unsigned char nsegs)
4512 {
4513 	const struct in6_addr *addr;
4514 	int i, ret = 0, found = 0;
4515 	struct inet6_ifaddr *ifp;
4516 	bool separated = false;
4517 	unsigned int hash;
4518 	bool hash_found;
4519 
4520 	rcu_read_lock();
4521 	for (i = 0; i < nsegs; i++) {
4522 		addr = &segs[i];
4523 		hash = inet6_addr_hash(net, addr);
4524 
4525 		hash_found = false;
4526 		hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
4527 
4528 			if (ipv6_addr_equal(&ifp->addr, addr)) {
4529 				hash_found = true;
4530 				break;
4531 			}
4532 		}
4533 
4534 		if (hash_found) {
4535 			if (found > 1 && separated) {
4536 				ret = 1;
4537 				break;
4538 			}
4539 
4540 			separated = false;
4541 			found++;
4542 		} else {
4543 			separated = true;
4544 		}
4545 	}
4546 	rcu_read_unlock();
4547 
4548 	return ret;
4549 }
4550 
4551 /*
4552  *	Periodic address status verification
4553  */
4554 
4555 static void addrconf_verify_rtnl(struct net *net)
4556 {
4557 	unsigned long now, next, next_sec, next_sched;
4558 	struct inet6_ifaddr *ifp;
4559 	int i;
4560 
4561 	ASSERT_RTNL();
4562 
4563 	rcu_read_lock_bh();
4564 	now = jiffies;
4565 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4566 
4567 	cancel_delayed_work(&net->ipv6.addr_chk_work);
4568 
4569 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4570 restart:
4571 		hlist_for_each_entry_rcu_bh(ifp, &net->ipv6.inet6_addr_lst[i], addr_lst) {
4572 			unsigned long age;
4573 
4574 			/* When setting preferred_lft to a value not zero or
4575 			 * infinity, while valid_lft is infinity
4576 			 * IFA_F_PERMANENT has a non-infinity life time.
4577 			 */
4578 			if ((ifp->flags & IFA_F_PERMANENT) &&
4579 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4580 				continue;
4581 
4582 			spin_lock(&ifp->lock);
4583 			/* We try to batch several events at once. */
4584 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4585 
4586 			if ((ifp->flags&IFA_F_TEMPORARY) &&
4587 			    !(ifp->flags&IFA_F_TENTATIVE) &&
4588 			    ifp->prefered_lft != INFINITY_LIFE_TIME &&
4589 			    !ifp->regen_count && ifp->ifpub) {
4590 				/* This is a non-regenerated temporary addr. */
4591 
4592 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
4593 					ifp->idev->cnf.dad_transmits *
4594 					max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
4595 
4596 				if (age + regen_advance >= ifp->prefered_lft) {
4597 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4598 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4599 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4600 
4601 					ifp->regen_count++;
4602 					in6_ifa_hold(ifp);
4603 					in6_ifa_hold(ifpub);
4604 					spin_unlock(&ifp->lock);
4605 
4606 					spin_lock(&ifpub->lock);
4607 					ifpub->regen_count = 0;
4608 					spin_unlock(&ifpub->lock);
4609 					rcu_read_unlock_bh();
4610 					ipv6_create_tempaddr(ifpub, true);
4611 					in6_ifa_put(ifpub);
4612 					in6_ifa_put(ifp);
4613 					rcu_read_lock_bh();
4614 					goto restart;
4615 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4616 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4617 			}
4618 
4619 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4620 			    age >= ifp->valid_lft) {
4621 				spin_unlock(&ifp->lock);
4622 				in6_ifa_hold(ifp);
4623 				rcu_read_unlock_bh();
4624 				ipv6_del_addr(ifp);
4625 				rcu_read_lock_bh();
4626 				goto restart;
4627 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4628 				spin_unlock(&ifp->lock);
4629 				continue;
4630 			} else if (age >= ifp->prefered_lft) {
4631 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4632 				int deprecate = 0;
4633 
4634 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4635 					deprecate = 1;
4636 					ifp->flags |= IFA_F_DEPRECATED;
4637 				}
4638 
4639 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4640 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4641 					next = ifp->tstamp + ifp->valid_lft * HZ;
4642 
4643 				spin_unlock(&ifp->lock);
4644 
4645 				if (deprecate) {
4646 					in6_ifa_hold(ifp);
4647 
4648 					ipv6_ifa_notify(0, ifp);
4649 					in6_ifa_put(ifp);
4650 					goto restart;
4651 				}
4652 			} else {
4653 				/* ifp->prefered_lft <= ifp->valid_lft */
4654 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4655 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4656 				spin_unlock(&ifp->lock);
4657 			}
4658 		}
4659 	}
4660 
4661 	next_sec = round_jiffies_up(next);
4662 	next_sched = next;
4663 
4664 	/* If rounded timeout is accurate enough, accept it. */
4665 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4666 		next_sched = next_sec;
4667 
4668 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4669 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4670 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4671 
4672 	pr_debug("now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4673 		 now, next, next_sec, next_sched);
4674 	mod_delayed_work(addrconf_wq, &net->ipv6.addr_chk_work, next_sched - now);
4675 	rcu_read_unlock_bh();
4676 }
4677 
4678 static void addrconf_verify_work(struct work_struct *w)
4679 {
4680 	struct net *net = container_of(to_delayed_work(w), struct net,
4681 				       ipv6.addr_chk_work);
4682 
4683 	rtnl_lock();
4684 	addrconf_verify_rtnl(net);
4685 	rtnl_unlock();
4686 }
4687 
4688 static void addrconf_verify(struct net *net)
4689 {
4690 	mod_delayed_work(addrconf_wq, &net->ipv6.addr_chk_work, 0);
4691 }
4692 
4693 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4694 				     struct in6_addr **peer_pfx)
4695 {
4696 	struct in6_addr *pfx = NULL;
4697 
4698 	*peer_pfx = NULL;
4699 
4700 	if (addr)
4701 		pfx = nla_data(addr);
4702 
4703 	if (local) {
4704 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4705 			*peer_pfx = pfx;
4706 		pfx = nla_data(local);
4707 	}
4708 
4709 	return pfx;
4710 }
4711 
4712 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4713 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4714 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4715 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4716 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4717 	[IFA_RT_PRIORITY]	= { .len = sizeof(u32) },
4718 	[IFA_TARGET_NETNSID]	= { .type = NLA_S32 },
4719 	[IFA_PROTO]		= { .type = NLA_U8 },
4720 };
4721 
4722 static int
4723 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4724 		  struct netlink_ext_ack *extack)
4725 {
4726 	struct net *net = sock_net(skb->sk);
4727 	struct ifaddrmsg *ifm;
4728 	struct nlattr *tb[IFA_MAX+1];
4729 	struct in6_addr *pfx, *peer_pfx;
4730 	u32 ifa_flags;
4731 	int err;
4732 
4733 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4734 				     ifa_ipv6_policy, extack);
4735 	if (err < 0)
4736 		return err;
4737 
4738 	ifm = nlmsg_data(nlh);
4739 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4740 	if (!pfx)
4741 		return -EINVAL;
4742 
4743 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4744 
4745 	/* We ignore other flags so far. */
4746 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4747 
4748 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4749 			      ifm->ifa_prefixlen, extack);
4750 }
4751 
4752 static int modify_prefix_route(struct inet6_ifaddr *ifp,
4753 			       unsigned long expires, u32 flags,
4754 			       bool modify_peer)
4755 {
4756 	struct fib6_info *f6i;
4757 	u32 prio;
4758 
4759 	f6i = addrconf_get_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4760 					ifp->prefix_len,
4761 					ifp->idev->dev, 0, RTF_DEFAULT, true);
4762 	if (!f6i)
4763 		return -ENOENT;
4764 
4765 	prio = ifp->rt_priority ? : IP6_RT_PRIO_ADDRCONF;
4766 	if (f6i->fib6_metric != prio) {
4767 		/* delete old one */
4768 		ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
4769 
4770 		/* add new one */
4771 		addrconf_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4772 				      ifp->prefix_len,
4773 				      ifp->rt_priority, ifp->idev->dev,
4774 				      expires, flags, GFP_KERNEL);
4775 	} else {
4776 		if (!expires)
4777 			fib6_clean_expires(f6i);
4778 		else
4779 			fib6_set_expires(f6i, expires);
4780 
4781 		fib6_info_release(f6i);
4782 	}
4783 
4784 	return 0;
4785 }
4786 
4787 static int inet6_addr_modify(struct net *net, struct inet6_ifaddr *ifp,
4788 			     struct ifa6_config *cfg)
4789 {
4790 	u32 flags;
4791 	clock_t expires;
4792 	unsigned long timeout;
4793 	bool was_managetempaddr;
4794 	bool had_prefixroute;
4795 	bool new_peer = false;
4796 
4797 	ASSERT_RTNL();
4798 
4799 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
4800 		return -EINVAL;
4801 
4802 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR &&
4803 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4804 		return -EINVAL;
4805 
4806 	if (!(ifp->flags & IFA_F_TENTATIVE) || ifp->flags & IFA_F_DADFAILED)
4807 		cfg->ifa_flags &= ~IFA_F_OPTIMISTIC;
4808 
4809 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
4810 	if (addrconf_finite_timeout(timeout)) {
4811 		expires = jiffies_to_clock_t(timeout * HZ);
4812 		cfg->valid_lft = timeout;
4813 		flags = RTF_EXPIRES;
4814 	} else {
4815 		expires = 0;
4816 		flags = 0;
4817 		cfg->ifa_flags |= IFA_F_PERMANENT;
4818 	}
4819 
4820 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
4821 	if (addrconf_finite_timeout(timeout)) {
4822 		if (timeout == 0)
4823 			cfg->ifa_flags |= IFA_F_DEPRECATED;
4824 		cfg->preferred_lft = timeout;
4825 	}
4826 
4827 	if (cfg->peer_pfx &&
4828 	    memcmp(&ifp->peer_addr, cfg->peer_pfx, sizeof(struct in6_addr))) {
4829 		if (!ipv6_addr_any(&ifp->peer_addr))
4830 			cleanup_prefix_route(ifp, expires, true, true);
4831 		new_peer = true;
4832 	}
4833 
4834 	spin_lock_bh(&ifp->lock);
4835 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4836 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4837 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4838 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4839 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4840 			IFA_F_NOPREFIXROUTE);
4841 	ifp->flags |= cfg->ifa_flags;
4842 	ifp->tstamp = jiffies;
4843 	ifp->valid_lft = cfg->valid_lft;
4844 	ifp->prefered_lft = cfg->preferred_lft;
4845 	ifp->ifa_proto = cfg->ifa_proto;
4846 
4847 	if (cfg->rt_priority && cfg->rt_priority != ifp->rt_priority)
4848 		ifp->rt_priority = cfg->rt_priority;
4849 
4850 	if (new_peer)
4851 		ifp->peer_addr = *cfg->peer_pfx;
4852 
4853 	spin_unlock_bh(&ifp->lock);
4854 	if (!(ifp->flags&IFA_F_TENTATIVE))
4855 		ipv6_ifa_notify(0, ifp);
4856 
4857 	if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
4858 		int rc = -ENOENT;
4859 
4860 		if (had_prefixroute)
4861 			rc = modify_prefix_route(ifp, expires, flags, false);
4862 
4863 		/* prefix route could have been deleted; if so restore it */
4864 		if (rc == -ENOENT) {
4865 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4866 					      ifp->rt_priority, ifp->idev->dev,
4867 					      expires, flags, GFP_KERNEL);
4868 		}
4869 
4870 		if (had_prefixroute && !ipv6_addr_any(&ifp->peer_addr))
4871 			rc = modify_prefix_route(ifp, expires, flags, true);
4872 
4873 		if (rc == -ENOENT && !ipv6_addr_any(&ifp->peer_addr)) {
4874 			addrconf_prefix_route(&ifp->peer_addr, ifp->prefix_len,
4875 					      ifp->rt_priority, ifp->idev->dev,
4876 					      expires, flags, GFP_KERNEL);
4877 		}
4878 	} else if (had_prefixroute) {
4879 		enum cleanup_prefix_rt_t action;
4880 		unsigned long rt_expires;
4881 
4882 		write_lock_bh(&ifp->idev->lock);
4883 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4884 		write_unlock_bh(&ifp->idev->lock);
4885 
4886 		if (action != CLEANUP_PREFIX_RT_NOP) {
4887 			cleanup_prefix_route(ifp, rt_expires,
4888 				action == CLEANUP_PREFIX_RT_DEL, false);
4889 		}
4890 	}
4891 
4892 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4893 		if (was_managetempaddr &&
4894 		    !(ifp->flags & IFA_F_MANAGETEMPADDR)) {
4895 			cfg->valid_lft = 0;
4896 			cfg->preferred_lft = 0;
4897 		}
4898 		manage_tempaddrs(ifp->idev, ifp, cfg->valid_lft,
4899 				 cfg->preferred_lft, !was_managetempaddr,
4900 				 jiffies);
4901 	}
4902 
4903 	addrconf_verify_rtnl(net);
4904 
4905 	return 0;
4906 }
4907 
4908 static int
4909 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4910 		  struct netlink_ext_ack *extack)
4911 {
4912 	struct net *net = sock_net(skb->sk);
4913 	struct ifaddrmsg *ifm;
4914 	struct nlattr *tb[IFA_MAX+1];
4915 	struct in6_addr *peer_pfx;
4916 	struct inet6_ifaddr *ifa;
4917 	struct net_device *dev;
4918 	struct inet6_dev *idev;
4919 	struct ifa6_config cfg;
4920 	int err;
4921 
4922 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4923 				     ifa_ipv6_policy, extack);
4924 	if (err < 0)
4925 		return err;
4926 
4927 	memset(&cfg, 0, sizeof(cfg));
4928 
4929 	ifm = nlmsg_data(nlh);
4930 	cfg.pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4931 	if (!cfg.pfx)
4932 		return -EINVAL;
4933 
4934 	cfg.peer_pfx = peer_pfx;
4935 	cfg.plen = ifm->ifa_prefixlen;
4936 	if (tb[IFA_RT_PRIORITY])
4937 		cfg.rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
4938 
4939 	if (tb[IFA_PROTO])
4940 		cfg.ifa_proto = nla_get_u8(tb[IFA_PROTO]);
4941 
4942 	cfg.valid_lft = INFINITY_LIFE_TIME;
4943 	cfg.preferred_lft = INFINITY_LIFE_TIME;
4944 
4945 	if (tb[IFA_CACHEINFO]) {
4946 		struct ifa_cacheinfo *ci;
4947 
4948 		ci = nla_data(tb[IFA_CACHEINFO]);
4949 		cfg.valid_lft = ci->ifa_valid;
4950 		cfg.preferred_lft = ci->ifa_prefered;
4951 	}
4952 
4953 	dev =  __dev_get_by_index(net, ifm->ifa_index);
4954 	if (!dev) {
4955 		NL_SET_ERR_MSG_MOD(extack, "Unable to find the interface");
4956 		return -ENODEV;
4957 	}
4958 
4959 	if (tb[IFA_FLAGS])
4960 		cfg.ifa_flags = nla_get_u32(tb[IFA_FLAGS]);
4961 	else
4962 		cfg.ifa_flags = ifm->ifa_flags;
4963 
4964 	/* We ignore other flags so far. */
4965 	cfg.ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS |
4966 			 IFA_F_MANAGETEMPADDR | IFA_F_NOPREFIXROUTE |
4967 			 IFA_F_MCAUTOJOIN | IFA_F_OPTIMISTIC;
4968 
4969 	idev = ipv6_find_idev(dev);
4970 	if (IS_ERR(idev))
4971 		return PTR_ERR(idev);
4972 
4973 	if (!ipv6_allow_optimistic_dad(net, idev))
4974 		cfg.ifa_flags &= ~IFA_F_OPTIMISTIC;
4975 
4976 	if (cfg.ifa_flags & IFA_F_NODAD &&
4977 	    cfg.ifa_flags & IFA_F_OPTIMISTIC) {
4978 		NL_SET_ERR_MSG(extack, "IFA_F_NODAD and IFA_F_OPTIMISTIC are mutually exclusive");
4979 		return -EINVAL;
4980 	}
4981 
4982 	ifa = ipv6_get_ifaddr(net, cfg.pfx, dev, 1);
4983 	if (!ifa) {
4984 		/*
4985 		 * It would be best to check for !NLM_F_CREATE here but
4986 		 * userspace already relies on not having to provide this.
4987 		 */
4988 		return inet6_addr_add(net, ifm->ifa_index, &cfg, extack);
4989 	}
4990 
4991 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
4992 	    !(nlh->nlmsg_flags & NLM_F_REPLACE)) {
4993 		NL_SET_ERR_MSG_MOD(extack, "address already assigned");
4994 		err = -EEXIST;
4995 	} else {
4996 		err = inet6_addr_modify(net, ifa, &cfg);
4997 	}
4998 
4999 	in6_ifa_put(ifa);
5000 
5001 	return err;
5002 }
5003 
5004 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
5005 			  u8 scope, int ifindex)
5006 {
5007 	struct ifaddrmsg *ifm;
5008 
5009 	ifm = nlmsg_data(nlh);
5010 	ifm->ifa_family = AF_INET6;
5011 	ifm->ifa_prefixlen = prefixlen;
5012 	ifm->ifa_flags = flags;
5013 	ifm->ifa_scope = scope;
5014 	ifm->ifa_index = ifindex;
5015 }
5016 
5017 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
5018 			 unsigned long tstamp, u32 preferred, u32 valid)
5019 {
5020 	struct ifa_cacheinfo ci;
5021 
5022 	ci.cstamp = cstamp_delta(cstamp);
5023 	ci.tstamp = cstamp_delta(tstamp);
5024 	ci.ifa_prefered = preferred;
5025 	ci.ifa_valid = valid;
5026 
5027 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
5028 }
5029 
5030 static inline int rt_scope(int ifa_scope)
5031 {
5032 	if (ifa_scope & IFA_HOST)
5033 		return RT_SCOPE_HOST;
5034 	else if (ifa_scope & IFA_LINK)
5035 		return RT_SCOPE_LINK;
5036 	else if (ifa_scope & IFA_SITE)
5037 		return RT_SCOPE_SITE;
5038 	else
5039 		return RT_SCOPE_UNIVERSE;
5040 }
5041 
5042 static inline int inet6_ifaddr_msgsize(void)
5043 {
5044 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
5045 	       + nla_total_size(16) /* IFA_LOCAL */
5046 	       + nla_total_size(16) /* IFA_ADDRESS */
5047 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
5048 	       + nla_total_size(4)  /* IFA_FLAGS */
5049 	       + nla_total_size(1)  /* IFA_PROTO */
5050 	       + nla_total_size(4)  /* IFA_RT_PRIORITY */;
5051 }
5052 
5053 enum addr_type_t {
5054 	UNICAST_ADDR,
5055 	MULTICAST_ADDR,
5056 	ANYCAST_ADDR,
5057 };
5058 
5059 struct inet6_fill_args {
5060 	u32 portid;
5061 	u32 seq;
5062 	int event;
5063 	unsigned int flags;
5064 	int netnsid;
5065 	int ifindex;
5066 	enum addr_type_t type;
5067 };
5068 
5069 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
5070 			     struct inet6_fill_args *args)
5071 {
5072 	struct nlmsghdr  *nlh;
5073 	u32 preferred, valid;
5074 
5075 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5076 			sizeof(struct ifaddrmsg), args->flags);
5077 	if (!nlh)
5078 		return -EMSGSIZE;
5079 
5080 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
5081 		      ifa->idev->dev->ifindex);
5082 
5083 	if (args->netnsid >= 0 &&
5084 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
5085 		goto error;
5086 
5087 	spin_lock_bh(&ifa->lock);
5088 	if (!((ifa->flags&IFA_F_PERMANENT) &&
5089 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
5090 		preferred = ifa->prefered_lft;
5091 		valid = ifa->valid_lft;
5092 		if (preferred != INFINITY_LIFE_TIME) {
5093 			long tval = (jiffies - ifa->tstamp)/HZ;
5094 			if (preferred > tval)
5095 				preferred -= tval;
5096 			else
5097 				preferred = 0;
5098 			if (valid != INFINITY_LIFE_TIME) {
5099 				if (valid > tval)
5100 					valid -= tval;
5101 				else
5102 					valid = 0;
5103 			}
5104 		}
5105 	} else {
5106 		preferred = INFINITY_LIFE_TIME;
5107 		valid = INFINITY_LIFE_TIME;
5108 	}
5109 	spin_unlock_bh(&ifa->lock);
5110 
5111 	if (!ipv6_addr_any(&ifa->peer_addr)) {
5112 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
5113 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
5114 			goto error;
5115 	} else
5116 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
5117 			goto error;
5118 
5119 	if (ifa->rt_priority &&
5120 	    nla_put_u32(skb, IFA_RT_PRIORITY, ifa->rt_priority))
5121 		goto error;
5122 
5123 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
5124 		goto error;
5125 
5126 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
5127 		goto error;
5128 
5129 	if (ifa->ifa_proto &&
5130 	    nla_put_u8(skb, IFA_PROTO, ifa->ifa_proto))
5131 		goto error;
5132 
5133 	nlmsg_end(skb, nlh);
5134 	return 0;
5135 
5136 error:
5137 	nlmsg_cancel(skb, nlh);
5138 	return -EMSGSIZE;
5139 }
5140 
5141 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
5142 			       struct inet6_fill_args *args)
5143 {
5144 	struct nlmsghdr  *nlh;
5145 	u8 scope = RT_SCOPE_UNIVERSE;
5146 	int ifindex = ifmca->idev->dev->ifindex;
5147 
5148 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
5149 		scope = RT_SCOPE_SITE;
5150 
5151 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5152 			sizeof(struct ifaddrmsg), args->flags);
5153 	if (!nlh)
5154 		return -EMSGSIZE;
5155 
5156 	if (args->netnsid >= 0 &&
5157 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) {
5158 		nlmsg_cancel(skb, nlh);
5159 		return -EMSGSIZE;
5160 	}
5161 
5162 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5163 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
5164 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
5165 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5166 		nlmsg_cancel(skb, nlh);
5167 		return -EMSGSIZE;
5168 	}
5169 
5170 	nlmsg_end(skb, nlh);
5171 	return 0;
5172 }
5173 
5174 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
5175 			       struct inet6_fill_args *args)
5176 {
5177 	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
5178 	int ifindex = dev ? dev->ifindex : 1;
5179 	struct nlmsghdr  *nlh;
5180 	u8 scope = RT_SCOPE_UNIVERSE;
5181 
5182 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
5183 		scope = RT_SCOPE_SITE;
5184 
5185 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5186 			sizeof(struct ifaddrmsg), args->flags);
5187 	if (!nlh)
5188 		return -EMSGSIZE;
5189 
5190 	if (args->netnsid >= 0 &&
5191 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) {
5192 		nlmsg_cancel(skb, nlh);
5193 		return -EMSGSIZE;
5194 	}
5195 
5196 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5197 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
5198 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
5199 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5200 		nlmsg_cancel(skb, nlh);
5201 		return -EMSGSIZE;
5202 	}
5203 
5204 	nlmsg_end(skb, nlh);
5205 	return 0;
5206 }
5207 
5208 /* called with rcu_read_lock() */
5209 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
5210 			  struct netlink_callback *cb, int s_ip_idx,
5211 			  struct inet6_fill_args *fillargs)
5212 {
5213 	struct ifmcaddr6 *ifmca;
5214 	struct ifacaddr6 *ifaca;
5215 	int ip_idx = 0;
5216 	int err = 1;
5217 
5218 	read_lock_bh(&idev->lock);
5219 	switch (fillargs->type) {
5220 	case UNICAST_ADDR: {
5221 		struct inet6_ifaddr *ifa;
5222 		fillargs->event = RTM_NEWADDR;
5223 
5224 		/* unicast address incl. temp addr */
5225 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
5226 			if (ip_idx < s_ip_idx)
5227 				goto next;
5228 			err = inet6_fill_ifaddr(skb, ifa, fillargs);
5229 			if (err < 0)
5230 				break;
5231 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
5232 next:
5233 			ip_idx++;
5234 		}
5235 		break;
5236 	}
5237 	case MULTICAST_ADDR:
5238 		read_unlock_bh(&idev->lock);
5239 		fillargs->event = RTM_GETMULTICAST;
5240 
5241 		/* multicast address */
5242 		for (ifmca = rtnl_dereference(idev->mc_list);
5243 		     ifmca;
5244 		     ifmca = rtnl_dereference(ifmca->next), ip_idx++) {
5245 			if (ip_idx < s_ip_idx)
5246 				continue;
5247 			err = inet6_fill_ifmcaddr(skb, ifmca, fillargs);
5248 			if (err < 0)
5249 				break;
5250 		}
5251 		read_lock_bh(&idev->lock);
5252 		break;
5253 	case ANYCAST_ADDR:
5254 		fillargs->event = RTM_GETANYCAST;
5255 		/* anycast address */
5256 		for (ifaca = idev->ac_list; ifaca;
5257 		     ifaca = ifaca->aca_next, ip_idx++) {
5258 			if (ip_idx < s_ip_idx)
5259 				continue;
5260 			err = inet6_fill_ifacaddr(skb, ifaca, fillargs);
5261 			if (err < 0)
5262 				break;
5263 		}
5264 		break;
5265 	default:
5266 		break;
5267 	}
5268 	read_unlock_bh(&idev->lock);
5269 	cb->args[2] = ip_idx;
5270 	return err;
5271 }
5272 
5273 static int inet6_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
5274 				       struct inet6_fill_args *fillargs,
5275 				       struct net **tgt_net, struct sock *sk,
5276 				       struct netlink_callback *cb)
5277 {
5278 	struct netlink_ext_ack *extack = cb->extack;
5279 	struct nlattr *tb[IFA_MAX+1];
5280 	struct ifaddrmsg *ifm;
5281 	int err, i;
5282 
5283 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5284 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for address dump request");
5285 		return -EINVAL;
5286 	}
5287 
5288 	ifm = nlmsg_data(nlh);
5289 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5290 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address dump request");
5291 		return -EINVAL;
5292 	}
5293 
5294 	fillargs->ifindex = ifm->ifa_index;
5295 	if (fillargs->ifindex) {
5296 		cb->answer_flags |= NLM_F_DUMP_FILTERED;
5297 		fillargs->flags |= NLM_F_DUMP_FILTERED;
5298 	}
5299 
5300 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5301 					    ifa_ipv6_policy, extack);
5302 	if (err < 0)
5303 		return err;
5304 
5305 	for (i = 0; i <= IFA_MAX; ++i) {
5306 		if (!tb[i])
5307 			continue;
5308 
5309 		if (i == IFA_TARGET_NETNSID) {
5310 			struct net *net;
5311 
5312 			fillargs->netnsid = nla_get_s32(tb[i]);
5313 			net = rtnl_get_net_ns_capable(sk, fillargs->netnsid);
5314 			if (IS_ERR(net)) {
5315 				fillargs->netnsid = -1;
5316 				NL_SET_ERR_MSG_MOD(extack, "Invalid target network namespace id");
5317 				return PTR_ERR(net);
5318 			}
5319 			*tgt_net = net;
5320 		} else {
5321 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request");
5322 			return -EINVAL;
5323 		}
5324 	}
5325 
5326 	return 0;
5327 }
5328 
5329 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
5330 			   enum addr_type_t type)
5331 {
5332 	const struct nlmsghdr *nlh = cb->nlh;
5333 	struct inet6_fill_args fillargs = {
5334 		.portid = NETLINK_CB(cb->skb).portid,
5335 		.seq = cb->nlh->nlmsg_seq,
5336 		.flags = NLM_F_MULTI,
5337 		.netnsid = -1,
5338 		.type = type,
5339 	};
5340 	struct net *tgt_net = sock_net(skb->sk);
5341 	int idx, s_idx, s_ip_idx;
5342 	int h, s_h;
5343 	struct net_device *dev;
5344 	struct inet6_dev *idev;
5345 	struct hlist_head *head;
5346 	int err = 0;
5347 
5348 	s_h = cb->args[0];
5349 	s_idx = idx = cb->args[1];
5350 	s_ip_idx = cb->args[2];
5351 
5352 	if (cb->strict_check) {
5353 		err = inet6_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
5354 						  skb->sk, cb);
5355 		if (err < 0)
5356 			goto put_tgt_net;
5357 
5358 		err = 0;
5359 		if (fillargs.ifindex) {
5360 			dev = __dev_get_by_index(tgt_net, fillargs.ifindex);
5361 			if (!dev) {
5362 				err = -ENODEV;
5363 				goto put_tgt_net;
5364 			}
5365 			idev = __in6_dev_get(dev);
5366 			if (idev) {
5367 				err = in6_dump_addrs(idev, skb, cb, s_ip_idx,
5368 						     &fillargs);
5369 				if (err > 0)
5370 					err = 0;
5371 			}
5372 			goto put_tgt_net;
5373 		}
5374 	}
5375 
5376 	rcu_read_lock();
5377 	cb->seq = inet6_base_seq(tgt_net);
5378 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5379 		idx = 0;
5380 		head = &tgt_net->dev_index_head[h];
5381 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5382 			if (idx < s_idx)
5383 				goto cont;
5384 			if (h > s_h || idx > s_idx)
5385 				s_ip_idx = 0;
5386 			idev = __in6_dev_get(dev);
5387 			if (!idev)
5388 				goto cont;
5389 
5390 			if (in6_dump_addrs(idev, skb, cb, s_ip_idx,
5391 					   &fillargs) < 0)
5392 				goto done;
5393 cont:
5394 			idx++;
5395 		}
5396 	}
5397 done:
5398 	rcu_read_unlock();
5399 	cb->args[0] = h;
5400 	cb->args[1] = idx;
5401 put_tgt_net:
5402 	if (fillargs.netnsid >= 0)
5403 		put_net(tgt_net);
5404 
5405 	return skb->len ? : err;
5406 }
5407 
5408 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
5409 {
5410 	enum addr_type_t type = UNICAST_ADDR;
5411 
5412 	return inet6_dump_addr(skb, cb, type);
5413 }
5414 
5415 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
5416 {
5417 	enum addr_type_t type = MULTICAST_ADDR;
5418 
5419 	return inet6_dump_addr(skb, cb, type);
5420 }
5421 
5422 
5423 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
5424 {
5425 	enum addr_type_t type = ANYCAST_ADDR;
5426 
5427 	return inet6_dump_addr(skb, cb, type);
5428 }
5429 
5430 static int inet6_rtm_valid_getaddr_req(struct sk_buff *skb,
5431 				       const struct nlmsghdr *nlh,
5432 				       struct nlattr **tb,
5433 				       struct netlink_ext_ack *extack)
5434 {
5435 	struct ifaddrmsg *ifm;
5436 	int i, err;
5437 
5438 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5439 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for get address request");
5440 		return -EINVAL;
5441 	}
5442 
5443 	if (!netlink_strict_get_check(skb))
5444 		return nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
5445 					      ifa_ipv6_policy, extack);
5446 
5447 	ifm = nlmsg_data(nlh);
5448 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5449 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get address request");
5450 		return -EINVAL;
5451 	}
5452 
5453 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5454 					    ifa_ipv6_policy, extack);
5455 	if (err)
5456 		return err;
5457 
5458 	for (i = 0; i <= IFA_MAX; i++) {
5459 		if (!tb[i])
5460 			continue;
5461 
5462 		switch (i) {
5463 		case IFA_TARGET_NETNSID:
5464 		case IFA_ADDRESS:
5465 		case IFA_LOCAL:
5466 			break;
5467 		default:
5468 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get address request");
5469 			return -EINVAL;
5470 		}
5471 	}
5472 
5473 	return 0;
5474 }
5475 
5476 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5477 			     struct netlink_ext_ack *extack)
5478 {
5479 	struct net *tgt_net = sock_net(in_skb->sk);
5480 	struct inet6_fill_args fillargs = {
5481 		.portid = NETLINK_CB(in_skb).portid,
5482 		.seq = nlh->nlmsg_seq,
5483 		.event = RTM_NEWADDR,
5484 		.flags = 0,
5485 		.netnsid = -1,
5486 	};
5487 	struct ifaddrmsg *ifm;
5488 	struct nlattr *tb[IFA_MAX+1];
5489 	struct in6_addr *addr = NULL, *peer;
5490 	struct net_device *dev = NULL;
5491 	struct inet6_ifaddr *ifa;
5492 	struct sk_buff *skb;
5493 	int err;
5494 
5495 	err = inet6_rtm_valid_getaddr_req(in_skb, nlh, tb, extack);
5496 	if (err < 0)
5497 		return err;
5498 
5499 	if (tb[IFA_TARGET_NETNSID]) {
5500 		fillargs.netnsid = nla_get_s32(tb[IFA_TARGET_NETNSID]);
5501 
5502 		tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(in_skb).sk,
5503 						  fillargs.netnsid);
5504 		if (IS_ERR(tgt_net))
5505 			return PTR_ERR(tgt_net);
5506 	}
5507 
5508 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
5509 	if (!addr) {
5510 		err = -EINVAL;
5511 		goto errout;
5512 	}
5513 	ifm = nlmsg_data(nlh);
5514 	if (ifm->ifa_index)
5515 		dev = dev_get_by_index(tgt_net, ifm->ifa_index);
5516 
5517 	ifa = ipv6_get_ifaddr(tgt_net, addr, dev, 1);
5518 	if (!ifa) {
5519 		err = -EADDRNOTAVAIL;
5520 		goto errout;
5521 	}
5522 
5523 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
5524 	if (!skb) {
5525 		err = -ENOBUFS;
5526 		goto errout_ifa;
5527 	}
5528 
5529 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5530 	if (err < 0) {
5531 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5532 		WARN_ON(err == -EMSGSIZE);
5533 		kfree_skb(skb);
5534 		goto errout_ifa;
5535 	}
5536 	err = rtnl_unicast(skb, tgt_net, NETLINK_CB(in_skb).portid);
5537 errout_ifa:
5538 	in6_ifa_put(ifa);
5539 errout:
5540 	dev_put(dev);
5541 	if (fillargs.netnsid >= 0)
5542 		put_net(tgt_net);
5543 
5544 	return err;
5545 }
5546 
5547 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
5548 {
5549 	struct sk_buff *skb;
5550 	struct net *net = dev_net(ifa->idev->dev);
5551 	struct inet6_fill_args fillargs = {
5552 		.portid = 0,
5553 		.seq = 0,
5554 		.event = event,
5555 		.flags = 0,
5556 		.netnsid = -1,
5557 	};
5558 	int err = -ENOBUFS;
5559 
5560 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
5561 	if (!skb)
5562 		goto errout;
5563 
5564 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5565 	if (err < 0) {
5566 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5567 		WARN_ON(err == -EMSGSIZE);
5568 		kfree_skb(skb);
5569 		goto errout;
5570 	}
5571 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5572 	return;
5573 errout:
5574 	if (err < 0)
5575 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5576 }
5577 
5578 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
5579 				__s32 *array, int bytes)
5580 {
5581 	BUG_ON(bytes < (DEVCONF_MAX * 4));
5582 
5583 	memset(array, 0, bytes);
5584 	array[DEVCONF_FORWARDING] = cnf->forwarding;
5585 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
5586 	array[DEVCONF_MTU6] = cnf->mtu6;
5587 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
5588 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
5589 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
5590 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
5591 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
5592 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5593 		jiffies_to_msecs(cnf->rtr_solicit_interval);
5594 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5595 		jiffies_to_msecs(cnf->rtr_solicit_max_interval);
5596 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5597 		jiffies_to_msecs(cnf->rtr_solicit_delay);
5598 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
5599 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5600 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
5601 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5602 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
5603 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
5604 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
5605 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
5606 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
5607 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
5608 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
5609 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
5610 	array[DEVCONF_RA_DEFRTR_METRIC] = cnf->ra_defrtr_metric;
5611 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] = cnf->accept_ra_min_hop_limit;
5612 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
5613 #ifdef CONFIG_IPV6_ROUTER_PREF
5614 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
5615 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5616 		jiffies_to_msecs(cnf->rtr_probe_interval);
5617 #ifdef CONFIG_IPV6_ROUTE_INFO
5618 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] = cnf->accept_ra_rt_info_min_plen;
5619 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
5620 #endif
5621 #endif
5622 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
5623 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
5624 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5625 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
5626 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
5627 #endif
5628 #ifdef CONFIG_IPV6_MROUTE
5629 	array[DEVCONF_MC_FORWARDING] = atomic_read(&cnf->mc_forwarding);
5630 #endif
5631 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
5632 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
5633 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
5634 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
5635 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
5636 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
5637 	array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
5638 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] = cnf->ignore_routes_with_linkdown;
5639 	/* we omit DEVCONF_STABLE_SECRET for now */
5640 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
5641 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
5642 	array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
5643 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
5644 	array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
5645 #ifdef CONFIG_IPV6_SEG6_HMAC
5646 	array[DEVCONF_SEG6_REQUIRE_HMAC] = cnf->seg6_require_hmac;
5647 #endif
5648 	array[DEVCONF_ENHANCED_DAD] = cnf->enhanced_dad;
5649 	array[DEVCONF_ADDR_GEN_MODE] = cnf->addr_gen_mode;
5650 	array[DEVCONF_DISABLE_POLICY] = cnf->disable_policy;
5651 	array[DEVCONF_NDISC_TCLASS] = cnf->ndisc_tclass;
5652 	array[DEVCONF_RPL_SEG_ENABLED] = cnf->rpl_seg_enabled;
5653 	array[DEVCONF_IOAM6_ENABLED] = cnf->ioam6_enabled;
5654 	array[DEVCONF_IOAM6_ID] = cnf->ioam6_id;
5655 	array[DEVCONF_IOAM6_ID_WIDE] = cnf->ioam6_id_wide;
5656 	array[DEVCONF_NDISC_EVICT_NOCARRIER] = cnf->ndisc_evict_nocarrier;
5657 	array[DEVCONF_ACCEPT_UNTRACKED_NA] = cnf->accept_untracked_na;
5658 	array[DEVCONF_ACCEPT_RA_MIN_LFT] = cnf->accept_ra_min_lft;
5659 }
5660 
5661 static inline size_t inet6_ifla6_size(void)
5662 {
5663 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5664 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5665 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5666 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5667 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5668 	     + nla_total_size(sizeof(struct in6_addr)) /* IFLA_INET6_TOKEN */
5669 	     + nla_total_size(1) /* IFLA_INET6_ADDR_GEN_MODE */
5670 	     + nla_total_size(4) /* IFLA_INET6_RA_MTU */
5671 	     + 0;
5672 }
5673 
5674 static inline size_t inet6_if_nlmsg_size(void)
5675 {
5676 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5677 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5678 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5679 	       + nla_total_size(4) /* IFLA_MTU */
5680 	       + nla_total_size(4) /* IFLA_LINK */
5681 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5682 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5683 }
5684 
5685 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5686 					int bytes)
5687 {
5688 	int i;
5689 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5690 	BUG_ON(pad < 0);
5691 
5692 	/* Use put_unaligned() because stats may not be aligned for u64. */
5693 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5694 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5695 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5696 
5697 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5698 }
5699 
5700 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5701 					int bytes, size_t syncpoff)
5702 {
5703 	int i, c;
5704 	u64 buff[IPSTATS_MIB_MAX];
5705 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5706 
5707 	BUG_ON(pad < 0);
5708 
5709 	memset(buff, 0, sizeof(buff));
5710 	buff[0] = IPSTATS_MIB_MAX;
5711 
5712 	for_each_possible_cpu(c) {
5713 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5714 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5715 	}
5716 
5717 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5718 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5719 }
5720 
5721 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5722 			     int bytes)
5723 {
5724 	switch (attrtype) {
5725 	case IFLA_INET6_STATS:
5726 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5727 				     offsetof(struct ipstats_mib, syncp));
5728 		break;
5729 	case IFLA_INET6_ICMP6STATS:
5730 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5731 		break;
5732 	}
5733 }
5734 
5735 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5736 				  u32 ext_filter_mask)
5737 {
5738 	struct nlattr *nla;
5739 	struct ifla_cacheinfo ci;
5740 
5741 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
5742 		goto nla_put_failure;
5743 	ci.max_reasm_len = IPV6_MAXPLEN;
5744 	ci.tstamp = cstamp_delta(idev->tstamp);
5745 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5746 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5747 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5748 		goto nla_put_failure;
5749 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5750 	if (!nla)
5751 		goto nla_put_failure;
5752 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5753 
5754 	/* XXX - MC not implemented */
5755 
5756 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5757 		return 0;
5758 
5759 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5760 	if (!nla)
5761 		goto nla_put_failure;
5762 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5763 
5764 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5765 	if (!nla)
5766 		goto nla_put_failure;
5767 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5768 
5769 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5770 	if (!nla)
5771 		goto nla_put_failure;
5772 	read_lock_bh(&idev->lock);
5773 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5774 	read_unlock_bh(&idev->lock);
5775 
5776 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->cnf.addr_gen_mode))
5777 		goto nla_put_failure;
5778 
5779 	if (idev->ra_mtu &&
5780 	    nla_put_u32(skb, IFLA_INET6_RA_MTU, idev->ra_mtu))
5781 		goto nla_put_failure;
5782 
5783 	return 0;
5784 
5785 nla_put_failure:
5786 	return -EMSGSIZE;
5787 }
5788 
5789 static size_t inet6_get_link_af_size(const struct net_device *dev,
5790 				     u32 ext_filter_mask)
5791 {
5792 	if (!__in6_dev_get(dev))
5793 		return 0;
5794 
5795 	return inet6_ifla6_size();
5796 }
5797 
5798 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5799 			      u32 ext_filter_mask)
5800 {
5801 	struct inet6_dev *idev = __in6_dev_get(dev);
5802 
5803 	if (!idev)
5804 		return -ENODATA;
5805 
5806 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5807 		return -EMSGSIZE;
5808 
5809 	return 0;
5810 }
5811 
5812 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token,
5813 			     struct netlink_ext_ack *extack)
5814 {
5815 	struct inet6_ifaddr *ifp;
5816 	struct net_device *dev = idev->dev;
5817 	bool clear_token, update_rs = false;
5818 	struct in6_addr ll_addr;
5819 
5820 	ASSERT_RTNL();
5821 
5822 	if (!token)
5823 		return -EINVAL;
5824 
5825 	if (dev->flags & IFF_LOOPBACK) {
5826 		NL_SET_ERR_MSG_MOD(extack, "Device is loopback");
5827 		return -EINVAL;
5828 	}
5829 
5830 	if (dev->flags & IFF_NOARP) {
5831 		NL_SET_ERR_MSG_MOD(extack,
5832 				   "Device does not do neighbour discovery");
5833 		return -EINVAL;
5834 	}
5835 
5836 	if (!ipv6_accept_ra(idev)) {
5837 		NL_SET_ERR_MSG_MOD(extack,
5838 				   "Router advertisement is disabled on device");
5839 		return -EINVAL;
5840 	}
5841 
5842 	if (idev->cnf.rtr_solicits == 0) {
5843 		NL_SET_ERR_MSG(extack,
5844 			       "Router solicitation is disabled on device");
5845 		return -EINVAL;
5846 	}
5847 
5848 	write_lock_bh(&idev->lock);
5849 
5850 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5851 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5852 
5853 	write_unlock_bh(&idev->lock);
5854 
5855 	clear_token = ipv6_addr_any(token);
5856 	if (clear_token)
5857 		goto update_lft;
5858 
5859 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5860 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5861 			     IFA_F_OPTIMISTIC)) {
5862 		/* If we're not ready, then normal ifup will take care
5863 		 * of this. Otherwise, we need to request our rs here.
5864 		 */
5865 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5866 		update_rs = true;
5867 	}
5868 
5869 update_lft:
5870 	write_lock_bh(&idev->lock);
5871 
5872 	if (update_rs) {
5873 		idev->if_flags |= IF_RS_SENT;
5874 		idev->rs_interval = rfc3315_s14_backoff_init(
5875 			idev->cnf.rtr_solicit_interval);
5876 		idev->rs_probes = 1;
5877 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5878 	}
5879 
5880 	/* Well, that's kinda nasty ... */
5881 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5882 		spin_lock(&ifp->lock);
5883 		if (ifp->tokenized) {
5884 			ifp->valid_lft = 0;
5885 			ifp->prefered_lft = 0;
5886 		}
5887 		spin_unlock(&ifp->lock);
5888 	}
5889 
5890 	write_unlock_bh(&idev->lock);
5891 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5892 	addrconf_verify_rtnl(dev_net(dev));
5893 	return 0;
5894 }
5895 
5896 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5897 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5898 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5899 	[IFLA_INET6_RA_MTU]		= { .type = NLA_REJECT,
5900 					    .reject_message =
5901 						"IFLA_INET6_RA_MTU can not be set" },
5902 };
5903 
5904 static int check_addr_gen_mode(int mode)
5905 {
5906 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5907 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5908 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5909 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5910 		return -EINVAL;
5911 	return 1;
5912 }
5913 
5914 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5915 				int mode)
5916 {
5917 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5918 	    !idev->cnf.stable_secret.initialized &&
5919 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5920 		return -EINVAL;
5921 	return 1;
5922 }
5923 
5924 static int inet6_validate_link_af(const struct net_device *dev,
5925 				  const struct nlattr *nla,
5926 				  struct netlink_ext_ack *extack)
5927 {
5928 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5929 	struct inet6_dev *idev = NULL;
5930 	int err;
5931 
5932 	if (dev) {
5933 		idev = __in6_dev_get(dev);
5934 		if (!idev)
5935 			return -EAFNOSUPPORT;
5936 	}
5937 
5938 	err = nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla,
5939 					  inet6_af_policy, extack);
5940 	if (err)
5941 		return err;
5942 
5943 	if (!tb[IFLA_INET6_TOKEN] && !tb[IFLA_INET6_ADDR_GEN_MODE])
5944 		return -EINVAL;
5945 
5946 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5947 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5948 
5949 		if (check_addr_gen_mode(mode) < 0)
5950 			return -EINVAL;
5951 		if (dev && check_stable_privacy(idev, dev_net(dev), mode) < 0)
5952 			return -EINVAL;
5953 	}
5954 
5955 	return 0;
5956 }
5957 
5958 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla,
5959 			     struct netlink_ext_ack *extack)
5960 {
5961 	struct inet6_dev *idev = __in6_dev_get(dev);
5962 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5963 	int err;
5964 
5965 	if (!idev)
5966 		return -EAFNOSUPPORT;
5967 
5968 	if (nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
5969 		return -EINVAL;
5970 
5971 	if (tb[IFLA_INET6_TOKEN]) {
5972 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]),
5973 					extack);
5974 		if (err)
5975 			return err;
5976 	}
5977 
5978 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5979 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5980 
5981 		idev->cnf.addr_gen_mode = mode;
5982 	}
5983 
5984 	return 0;
5985 }
5986 
5987 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
5988 			     u32 portid, u32 seq, int event, unsigned int flags)
5989 {
5990 	struct net_device *dev = idev->dev;
5991 	struct ifinfomsg *hdr;
5992 	struct nlmsghdr *nlh;
5993 	void *protoinfo;
5994 
5995 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
5996 	if (!nlh)
5997 		return -EMSGSIZE;
5998 
5999 	hdr = nlmsg_data(nlh);
6000 	hdr->ifi_family = AF_INET6;
6001 	hdr->__ifi_pad = 0;
6002 	hdr->ifi_type = dev->type;
6003 	hdr->ifi_index = dev->ifindex;
6004 	hdr->ifi_flags = dev_get_flags(dev);
6005 	hdr->ifi_change = 0;
6006 
6007 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
6008 	    (dev->addr_len &&
6009 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
6010 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
6011 	    (dev->ifindex != dev_get_iflink(dev) &&
6012 	     nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))) ||
6013 	    nla_put_u8(skb, IFLA_OPERSTATE,
6014 		       netif_running(dev) ? READ_ONCE(dev->operstate) : IF_OPER_DOWN))
6015 		goto nla_put_failure;
6016 	protoinfo = nla_nest_start_noflag(skb, IFLA_PROTINFO);
6017 	if (!protoinfo)
6018 		goto nla_put_failure;
6019 
6020 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
6021 		goto nla_put_failure;
6022 
6023 	nla_nest_end(skb, protoinfo);
6024 	nlmsg_end(skb, nlh);
6025 	return 0;
6026 
6027 nla_put_failure:
6028 	nlmsg_cancel(skb, nlh);
6029 	return -EMSGSIZE;
6030 }
6031 
6032 static int inet6_valid_dump_ifinfo(const struct nlmsghdr *nlh,
6033 				   struct netlink_ext_ack *extack)
6034 {
6035 	struct ifinfomsg *ifm;
6036 
6037 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
6038 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for link dump request");
6039 		return -EINVAL;
6040 	}
6041 
6042 	if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
6043 		NL_SET_ERR_MSG_MOD(extack, "Invalid data after header");
6044 		return -EINVAL;
6045 	}
6046 
6047 	ifm = nlmsg_data(nlh);
6048 	if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
6049 	    ifm->ifi_change || ifm->ifi_index) {
6050 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for dump request");
6051 		return -EINVAL;
6052 	}
6053 
6054 	return 0;
6055 }
6056 
6057 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
6058 {
6059 	struct net *net = sock_net(skb->sk);
6060 	int h, s_h;
6061 	int idx = 0, s_idx;
6062 	struct net_device *dev;
6063 	struct inet6_dev *idev;
6064 	struct hlist_head *head;
6065 
6066 	/* only requests using strict checking can pass data to
6067 	 * influence the dump
6068 	 */
6069 	if (cb->strict_check) {
6070 		int err = inet6_valid_dump_ifinfo(cb->nlh, cb->extack);
6071 
6072 		if (err < 0)
6073 			return err;
6074 	}
6075 
6076 	s_h = cb->args[0];
6077 	s_idx = cb->args[1];
6078 
6079 	rcu_read_lock();
6080 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
6081 		idx = 0;
6082 		head = &net->dev_index_head[h];
6083 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
6084 			if (idx < s_idx)
6085 				goto cont;
6086 			idev = __in6_dev_get(dev);
6087 			if (!idev)
6088 				goto cont;
6089 			if (inet6_fill_ifinfo(skb, idev,
6090 					      NETLINK_CB(cb->skb).portid,
6091 					      cb->nlh->nlmsg_seq,
6092 					      RTM_NEWLINK, NLM_F_MULTI) < 0)
6093 				goto out;
6094 cont:
6095 			idx++;
6096 		}
6097 	}
6098 out:
6099 	rcu_read_unlock();
6100 	cb->args[1] = idx;
6101 	cb->args[0] = h;
6102 
6103 	return skb->len;
6104 }
6105 
6106 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
6107 {
6108 	struct sk_buff *skb;
6109 	struct net *net = dev_net(idev->dev);
6110 	int err = -ENOBUFS;
6111 
6112 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
6113 	if (!skb)
6114 		goto errout;
6115 
6116 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
6117 	if (err < 0) {
6118 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
6119 		WARN_ON(err == -EMSGSIZE);
6120 		kfree_skb(skb);
6121 		goto errout;
6122 	}
6123 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
6124 	return;
6125 errout:
6126 	if (err < 0)
6127 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
6128 }
6129 
6130 static inline size_t inet6_prefix_nlmsg_size(void)
6131 {
6132 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
6133 	       + nla_total_size(sizeof(struct in6_addr))
6134 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
6135 }
6136 
6137 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
6138 			     struct prefix_info *pinfo, u32 portid, u32 seq,
6139 			     int event, unsigned int flags)
6140 {
6141 	struct prefixmsg *pmsg;
6142 	struct nlmsghdr *nlh;
6143 	struct prefix_cacheinfo	ci;
6144 
6145 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
6146 	if (!nlh)
6147 		return -EMSGSIZE;
6148 
6149 	pmsg = nlmsg_data(nlh);
6150 	pmsg->prefix_family = AF_INET6;
6151 	pmsg->prefix_pad1 = 0;
6152 	pmsg->prefix_pad2 = 0;
6153 	pmsg->prefix_ifindex = idev->dev->ifindex;
6154 	pmsg->prefix_len = pinfo->prefix_len;
6155 	pmsg->prefix_type = pinfo->type;
6156 	pmsg->prefix_pad3 = 0;
6157 	pmsg->prefix_flags = pinfo->flags;
6158 
6159 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
6160 		goto nla_put_failure;
6161 	ci.preferred_time = ntohl(pinfo->prefered);
6162 	ci.valid_time = ntohl(pinfo->valid);
6163 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
6164 		goto nla_put_failure;
6165 	nlmsg_end(skb, nlh);
6166 	return 0;
6167 
6168 nla_put_failure:
6169 	nlmsg_cancel(skb, nlh);
6170 	return -EMSGSIZE;
6171 }
6172 
6173 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
6174 			 struct prefix_info *pinfo)
6175 {
6176 	struct sk_buff *skb;
6177 	struct net *net = dev_net(idev->dev);
6178 	int err = -ENOBUFS;
6179 
6180 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
6181 	if (!skb)
6182 		goto errout;
6183 
6184 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
6185 	if (err < 0) {
6186 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
6187 		WARN_ON(err == -EMSGSIZE);
6188 		kfree_skb(skb);
6189 		goto errout;
6190 	}
6191 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
6192 	return;
6193 errout:
6194 	if (err < 0)
6195 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
6196 }
6197 
6198 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6199 {
6200 	struct net *net = dev_net(ifp->idev->dev);
6201 
6202 	if (event)
6203 		ASSERT_RTNL();
6204 
6205 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
6206 
6207 	switch (event) {
6208 	case RTM_NEWADDR:
6209 		/*
6210 		 * If the address was optimistic we inserted the route at the
6211 		 * start of our DAD process, so we don't need to do it again.
6212 		 * If the device was taken down in the middle of the DAD
6213 		 * cycle there is a race where we could get here without a
6214 		 * host route, so nothing to insert. That will be fixed when
6215 		 * the device is brought up.
6216 		 */
6217 		if (ifp->rt && !rcu_access_pointer(ifp->rt->fib6_node)) {
6218 			ip6_ins_rt(net, ifp->rt);
6219 		} else if (!ifp->rt && (ifp->idev->dev->flags & IFF_UP)) {
6220 			pr_warn("BUG: Address %pI6c on device %s is missing its host route.\n",
6221 				&ifp->addr, ifp->idev->dev->name);
6222 		}
6223 
6224 		if (ifp->idev->cnf.forwarding)
6225 			addrconf_join_anycast(ifp);
6226 		if (!ipv6_addr_any(&ifp->peer_addr))
6227 			addrconf_prefix_route(&ifp->peer_addr, 128,
6228 					      ifp->rt_priority, ifp->idev->dev,
6229 					      0, 0, GFP_ATOMIC);
6230 		break;
6231 	case RTM_DELADDR:
6232 		if (ifp->idev->cnf.forwarding)
6233 			addrconf_leave_anycast(ifp);
6234 		addrconf_leave_solict(ifp->idev, &ifp->addr);
6235 		if (!ipv6_addr_any(&ifp->peer_addr)) {
6236 			struct fib6_info *rt;
6237 
6238 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
6239 						       ifp->idev->dev, 0, 0,
6240 						       false);
6241 			if (rt)
6242 				ip6_del_rt(net, rt, false);
6243 		}
6244 		if (ifp->rt) {
6245 			ip6_del_rt(net, ifp->rt, false);
6246 			ifp->rt = NULL;
6247 		}
6248 		rt_genid_bump_ipv6(net);
6249 		break;
6250 	}
6251 	atomic_inc(&net->ipv6.dev_addr_genid);
6252 }
6253 
6254 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6255 {
6256 	if (likely(ifp->idev->dead == 0))
6257 		__ipv6_ifa_notify(event, ifp);
6258 }
6259 
6260 #ifdef CONFIG_SYSCTL
6261 
6262 static int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
6263 		void *buffer, size_t *lenp, loff_t *ppos)
6264 {
6265 	int *valp = ctl->data;
6266 	int val = *valp;
6267 	loff_t pos = *ppos;
6268 	struct ctl_table lctl;
6269 	int ret;
6270 
6271 	/*
6272 	 * ctl->data points to idev->cnf.forwarding, we should
6273 	 * not modify it until we get the rtnl lock.
6274 	 */
6275 	lctl = *ctl;
6276 	lctl.data = &val;
6277 
6278 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6279 
6280 	if (write)
6281 		ret = addrconf_fixup_forwarding(ctl, valp, val);
6282 	if (ret)
6283 		*ppos = pos;
6284 	return ret;
6285 }
6286 
6287 static int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
6288 		void *buffer, size_t *lenp, loff_t *ppos)
6289 {
6290 	struct inet6_dev *idev = ctl->extra1;
6291 	int min_mtu = IPV6_MIN_MTU;
6292 	struct ctl_table lctl;
6293 
6294 	lctl = *ctl;
6295 	lctl.extra1 = &min_mtu;
6296 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
6297 
6298 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
6299 }
6300 
6301 static void dev_disable_change(struct inet6_dev *idev)
6302 {
6303 	struct netdev_notifier_info info;
6304 
6305 	if (!idev || !idev->dev)
6306 		return;
6307 
6308 	netdev_notifier_info_init(&info, idev->dev);
6309 	if (idev->cnf.disable_ipv6)
6310 		addrconf_notify(NULL, NETDEV_DOWN, &info);
6311 	else
6312 		addrconf_notify(NULL, NETDEV_UP, &info);
6313 }
6314 
6315 static void addrconf_disable_change(struct net *net, __s32 newf)
6316 {
6317 	struct net_device *dev;
6318 	struct inet6_dev *idev;
6319 
6320 	for_each_netdev(net, dev) {
6321 		idev = __in6_dev_get(dev);
6322 		if (idev) {
6323 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
6324 
6325 			WRITE_ONCE(idev->cnf.disable_ipv6, newf);
6326 			if (changed)
6327 				dev_disable_change(idev);
6328 		}
6329 	}
6330 }
6331 
6332 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
6333 {
6334 	struct net *net;
6335 	int old;
6336 
6337 	if (!rtnl_trylock())
6338 		return restart_syscall();
6339 
6340 	net = (struct net *)table->extra2;
6341 	old = *p;
6342 	WRITE_ONCE(*p, newf);
6343 
6344 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
6345 		rtnl_unlock();
6346 		return 0;
6347 	}
6348 
6349 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
6350 		WRITE_ONCE(net->ipv6.devconf_dflt->disable_ipv6, newf);
6351 		addrconf_disable_change(net, newf);
6352 	} else if ((!newf) ^ (!old))
6353 		dev_disable_change((struct inet6_dev *)table->extra1);
6354 
6355 	rtnl_unlock();
6356 	return 0;
6357 }
6358 
6359 static int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
6360 		void *buffer, size_t *lenp, loff_t *ppos)
6361 {
6362 	int *valp = ctl->data;
6363 	int val = *valp;
6364 	loff_t pos = *ppos;
6365 	struct ctl_table lctl;
6366 	int ret;
6367 
6368 	/*
6369 	 * ctl->data points to idev->cnf.disable_ipv6, we should
6370 	 * not modify it until we get the rtnl lock.
6371 	 */
6372 	lctl = *ctl;
6373 	lctl.data = &val;
6374 
6375 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6376 
6377 	if (write)
6378 		ret = addrconf_disable_ipv6(ctl, valp, val);
6379 	if (ret)
6380 		*ppos = pos;
6381 	return ret;
6382 }
6383 
6384 static int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
6385 		void *buffer, size_t *lenp, loff_t *ppos)
6386 {
6387 	int *valp = ctl->data;
6388 	int ret;
6389 	int old, new;
6390 
6391 	old = *valp;
6392 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
6393 	new = *valp;
6394 
6395 	if (write && old != new) {
6396 		struct net *net = ctl->extra2;
6397 
6398 		if (!rtnl_trylock())
6399 			return restart_syscall();
6400 
6401 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
6402 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6403 						     NETCONFA_PROXY_NEIGH,
6404 						     NETCONFA_IFINDEX_DEFAULT,
6405 						     net->ipv6.devconf_dflt);
6406 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
6407 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6408 						     NETCONFA_PROXY_NEIGH,
6409 						     NETCONFA_IFINDEX_ALL,
6410 						     net->ipv6.devconf_all);
6411 		else {
6412 			struct inet6_dev *idev = ctl->extra1;
6413 
6414 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6415 						     NETCONFA_PROXY_NEIGH,
6416 						     idev->dev->ifindex,
6417 						     &idev->cnf);
6418 		}
6419 		rtnl_unlock();
6420 	}
6421 
6422 	return ret;
6423 }
6424 
6425 static int addrconf_sysctl_addr_gen_mode(struct ctl_table *ctl, int write,
6426 					 void *buffer, size_t *lenp,
6427 					 loff_t *ppos)
6428 {
6429 	int ret = 0;
6430 	u32 new_val;
6431 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
6432 	struct net *net = (struct net *)ctl->extra2;
6433 	struct ctl_table tmp = {
6434 		.data = &new_val,
6435 		.maxlen = sizeof(new_val),
6436 		.mode = ctl->mode,
6437 	};
6438 
6439 	if (!rtnl_trylock())
6440 		return restart_syscall();
6441 
6442 	new_val = *((u32 *)ctl->data);
6443 
6444 	ret = proc_douintvec(&tmp, write, buffer, lenp, ppos);
6445 	if (ret != 0)
6446 		goto out;
6447 
6448 	if (write) {
6449 		if (check_addr_gen_mode(new_val) < 0) {
6450 			ret = -EINVAL;
6451 			goto out;
6452 		}
6453 
6454 		if (idev) {
6455 			if (check_stable_privacy(idev, net, new_val) < 0) {
6456 				ret = -EINVAL;
6457 				goto out;
6458 			}
6459 
6460 			if (idev->cnf.addr_gen_mode != new_val) {
6461 				idev->cnf.addr_gen_mode = new_val;
6462 				addrconf_init_auto_addrs(idev->dev);
6463 			}
6464 		} else if (&net->ipv6.devconf_all->addr_gen_mode == ctl->data) {
6465 			struct net_device *dev;
6466 
6467 			net->ipv6.devconf_dflt->addr_gen_mode = new_val;
6468 			for_each_netdev(net, dev) {
6469 				idev = __in6_dev_get(dev);
6470 				if (idev &&
6471 				    idev->cnf.addr_gen_mode != new_val) {
6472 					idev->cnf.addr_gen_mode = new_val;
6473 					addrconf_init_auto_addrs(idev->dev);
6474 				}
6475 			}
6476 		}
6477 
6478 		*((u32 *)ctl->data) = new_val;
6479 	}
6480 
6481 out:
6482 	rtnl_unlock();
6483 
6484 	return ret;
6485 }
6486 
6487 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
6488 					 void *buffer, size_t *lenp,
6489 					 loff_t *ppos)
6490 {
6491 	int err;
6492 	struct in6_addr addr;
6493 	char str[IPV6_MAX_STRLEN];
6494 	struct ctl_table lctl = *ctl;
6495 	struct net *net = ctl->extra2;
6496 	struct ipv6_stable_secret *secret = ctl->data;
6497 
6498 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
6499 		return -EIO;
6500 
6501 	lctl.maxlen = IPV6_MAX_STRLEN;
6502 	lctl.data = str;
6503 
6504 	if (!rtnl_trylock())
6505 		return restart_syscall();
6506 
6507 	if (!write && !secret->initialized) {
6508 		err = -EIO;
6509 		goto out;
6510 	}
6511 
6512 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
6513 	if (err >= sizeof(str)) {
6514 		err = -EIO;
6515 		goto out;
6516 	}
6517 
6518 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
6519 	if (err || !write)
6520 		goto out;
6521 
6522 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
6523 		err = -EIO;
6524 		goto out;
6525 	}
6526 
6527 	secret->initialized = true;
6528 	secret->secret = addr;
6529 
6530 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
6531 		struct net_device *dev;
6532 
6533 		for_each_netdev(net, dev) {
6534 			struct inet6_dev *idev = __in6_dev_get(dev);
6535 
6536 			if (idev) {
6537 				idev->cnf.addr_gen_mode =
6538 					IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6539 			}
6540 		}
6541 	} else {
6542 		struct inet6_dev *idev = ctl->extra1;
6543 
6544 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6545 	}
6546 
6547 out:
6548 	rtnl_unlock();
6549 
6550 	return err;
6551 }
6552 
6553 static
6554 int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
6555 						int write, void *buffer,
6556 						size_t *lenp,
6557 						loff_t *ppos)
6558 {
6559 	int *valp = ctl->data;
6560 	int val = *valp;
6561 	loff_t pos = *ppos;
6562 	struct ctl_table lctl;
6563 	int ret;
6564 
6565 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
6566 	 * we should not modify it until we get the rtnl lock.
6567 	 */
6568 	lctl = *ctl;
6569 	lctl.data = &val;
6570 
6571 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6572 
6573 	if (write)
6574 		ret = addrconf_fixup_linkdown(ctl, valp, val);
6575 	if (ret)
6576 		*ppos = pos;
6577 	return ret;
6578 }
6579 
6580 static
6581 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
6582 {
6583 	if (rt) {
6584 		if (action)
6585 			rt->dst.flags |= DST_NOPOLICY;
6586 		else
6587 			rt->dst.flags &= ~DST_NOPOLICY;
6588 	}
6589 }
6590 
6591 static
6592 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
6593 {
6594 	struct inet6_ifaddr *ifa;
6595 
6596 	read_lock_bh(&idev->lock);
6597 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
6598 		spin_lock(&ifa->lock);
6599 		if (ifa->rt) {
6600 			/* host routes only use builtin fib6_nh */
6601 			struct fib6_nh *nh = ifa->rt->fib6_nh;
6602 			int cpu;
6603 
6604 			rcu_read_lock();
6605 			ifa->rt->dst_nopolicy = val ? true : false;
6606 			if (nh->rt6i_pcpu) {
6607 				for_each_possible_cpu(cpu) {
6608 					struct rt6_info **rtp;
6609 
6610 					rtp = per_cpu_ptr(nh->rt6i_pcpu, cpu);
6611 					addrconf_set_nopolicy(*rtp, val);
6612 				}
6613 			}
6614 			rcu_read_unlock();
6615 		}
6616 		spin_unlock(&ifa->lock);
6617 	}
6618 	read_unlock_bh(&idev->lock);
6619 }
6620 
6621 static
6622 int addrconf_disable_policy(struct ctl_table *ctl, int *valp, int val)
6623 {
6624 	struct inet6_dev *idev;
6625 	struct net *net;
6626 
6627 	if (!rtnl_trylock())
6628 		return restart_syscall();
6629 
6630 	*valp = val;
6631 
6632 	net = (struct net *)ctl->extra2;
6633 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
6634 		rtnl_unlock();
6635 		return 0;
6636 	}
6637 
6638 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
6639 		struct net_device *dev;
6640 
6641 		for_each_netdev(net, dev) {
6642 			idev = __in6_dev_get(dev);
6643 			if (idev)
6644 				addrconf_disable_policy_idev(idev, val);
6645 		}
6646 	} else {
6647 		idev = (struct inet6_dev *)ctl->extra1;
6648 		addrconf_disable_policy_idev(idev, val);
6649 	}
6650 
6651 	rtnl_unlock();
6652 	return 0;
6653 }
6654 
6655 static int addrconf_sysctl_disable_policy(struct ctl_table *ctl, int write,
6656 				   void *buffer, size_t *lenp, loff_t *ppos)
6657 {
6658 	int *valp = ctl->data;
6659 	int val = *valp;
6660 	loff_t pos = *ppos;
6661 	struct ctl_table lctl;
6662 	int ret;
6663 
6664 	lctl = *ctl;
6665 	lctl.data = &val;
6666 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6667 
6668 	if (write && (*valp != val))
6669 		ret = addrconf_disable_policy(ctl, valp, val);
6670 
6671 	if (ret)
6672 		*ppos = pos;
6673 
6674 	return ret;
6675 }
6676 
6677 static int minus_one = -1;
6678 static const int two_five_five = 255;
6679 static u32 ioam6_if_id_max = U16_MAX;
6680 
6681 static const struct ctl_table addrconf_sysctl[] = {
6682 	{
6683 		.procname	= "forwarding",
6684 		.data		= &ipv6_devconf.forwarding,
6685 		.maxlen		= sizeof(int),
6686 		.mode		= 0644,
6687 		.proc_handler	= addrconf_sysctl_forward,
6688 	},
6689 	{
6690 		.procname	= "hop_limit",
6691 		.data		= &ipv6_devconf.hop_limit,
6692 		.maxlen		= sizeof(int),
6693 		.mode		= 0644,
6694 		.proc_handler	= proc_dointvec_minmax,
6695 		.extra1		= (void *)SYSCTL_ONE,
6696 		.extra2		= (void *)&two_five_five,
6697 	},
6698 	{
6699 		.procname	= "mtu",
6700 		.data		= &ipv6_devconf.mtu6,
6701 		.maxlen		= sizeof(int),
6702 		.mode		= 0644,
6703 		.proc_handler	= addrconf_sysctl_mtu,
6704 	},
6705 	{
6706 		.procname	= "accept_ra",
6707 		.data		= &ipv6_devconf.accept_ra,
6708 		.maxlen		= sizeof(int),
6709 		.mode		= 0644,
6710 		.proc_handler	= proc_dointvec,
6711 	},
6712 	{
6713 		.procname	= "accept_redirects",
6714 		.data		= &ipv6_devconf.accept_redirects,
6715 		.maxlen		= sizeof(int),
6716 		.mode		= 0644,
6717 		.proc_handler	= proc_dointvec,
6718 	},
6719 	{
6720 		.procname	= "autoconf",
6721 		.data		= &ipv6_devconf.autoconf,
6722 		.maxlen		= sizeof(int),
6723 		.mode		= 0644,
6724 		.proc_handler	= proc_dointvec,
6725 	},
6726 	{
6727 		.procname	= "dad_transmits",
6728 		.data		= &ipv6_devconf.dad_transmits,
6729 		.maxlen		= sizeof(int),
6730 		.mode		= 0644,
6731 		.proc_handler	= proc_dointvec,
6732 	},
6733 	{
6734 		.procname	= "router_solicitations",
6735 		.data		= &ipv6_devconf.rtr_solicits,
6736 		.maxlen		= sizeof(int),
6737 		.mode		= 0644,
6738 		.proc_handler	= proc_dointvec_minmax,
6739 		.extra1		= &minus_one,
6740 	},
6741 	{
6742 		.procname	= "router_solicitation_interval",
6743 		.data		= &ipv6_devconf.rtr_solicit_interval,
6744 		.maxlen		= sizeof(int),
6745 		.mode		= 0644,
6746 		.proc_handler	= proc_dointvec_jiffies,
6747 	},
6748 	{
6749 		.procname	= "router_solicitation_max_interval",
6750 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6751 		.maxlen		= sizeof(int),
6752 		.mode		= 0644,
6753 		.proc_handler	= proc_dointvec_jiffies,
6754 	},
6755 	{
6756 		.procname	= "router_solicitation_delay",
6757 		.data		= &ipv6_devconf.rtr_solicit_delay,
6758 		.maxlen		= sizeof(int),
6759 		.mode		= 0644,
6760 		.proc_handler	= proc_dointvec_jiffies,
6761 	},
6762 	{
6763 		.procname	= "force_mld_version",
6764 		.data		= &ipv6_devconf.force_mld_version,
6765 		.maxlen		= sizeof(int),
6766 		.mode		= 0644,
6767 		.proc_handler	= proc_dointvec,
6768 	},
6769 	{
6770 		.procname	= "mldv1_unsolicited_report_interval",
6771 		.data		=
6772 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6773 		.maxlen		= sizeof(int),
6774 		.mode		= 0644,
6775 		.proc_handler	= proc_dointvec_ms_jiffies,
6776 	},
6777 	{
6778 		.procname	= "mldv2_unsolicited_report_interval",
6779 		.data		=
6780 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6781 		.maxlen		= sizeof(int),
6782 		.mode		= 0644,
6783 		.proc_handler	= proc_dointvec_ms_jiffies,
6784 	},
6785 	{
6786 		.procname	= "use_tempaddr",
6787 		.data		= &ipv6_devconf.use_tempaddr,
6788 		.maxlen		= sizeof(int),
6789 		.mode		= 0644,
6790 		.proc_handler	= proc_dointvec,
6791 	},
6792 	{
6793 		.procname	= "temp_valid_lft",
6794 		.data		= &ipv6_devconf.temp_valid_lft,
6795 		.maxlen		= sizeof(int),
6796 		.mode		= 0644,
6797 		.proc_handler	= proc_dointvec,
6798 	},
6799 	{
6800 		.procname	= "temp_prefered_lft",
6801 		.data		= &ipv6_devconf.temp_prefered_lft,
6802 		.maxlen		= sizeof(int),
6803 		.mode		= 0644,
6804 		.proc_handler	= proc_dointvec,
6805 	},
6806 	{
6807 		.procname	= "regen_max_retry",
6808 		.data		= &ipv6_devconf.regen_max_retry,
6809 		.maxlen		= sizeof(int),
6810 		.mode		= 0644,
6811 		.proc_handler	= proc_dointvec,
6812 	},
6813 	{
6814 		.procname	= "max_desync_factor",
6815 		.data		= &ipv6_devconf.max_desync_factor,
6816 		.maxlen		= sizeof(int),
6817 		.mode		= 0644,
6818 		.proc_handler	= proc_dointvec,
6819 	},
6820 	{
6821 		.procname	= "max_addresses",
6822 		.data		= &ipv6_devconf.max_addresses,
6823 		.maxlen		= sizeof(int),
6824 		.mode		= 0644,
6825 		.proc_handler	= proc_dointvec,
6826 	},
6827 	{
6828 		.procname	= "accept_ra_defrtr",
6829 		.data		= &ipv6_devconf.accept_ra_defrtr,
6830 		.maxlen		= sizeof(int),
6831 		.mode		= 0644,
6832 		.proc_handler	= proc_dointvec,
6833 	},
6834 	{
6835 		.procname	= "ra_defrtr_metric",
6836 		.data		= &ipv6_devconf.ra_defrtr_metric,
6837 		.maxlen		= sizeof(u32),
6838 		.mode		= 0644,
6839 		.proc_handler	= proc_douintvec_minmax,
6840 		.extra1		= (void *)SYSCTL_ONE,
6841 	},
6842 	{
6843 		.procname	= "accept_ra_min_hop_limit",
6844 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6845 		.maxlen		= sizeof(int),
6846 		.mode		= 0644,
6847 		.proc_handler	= proc_dointvec,
6848 	},
6849 	{
6850 		.procname	= "accept_ra_min_lft",
6851 		.data		= &ipv6_devconf.accept_ra_min_lft,
6852 		.maxlen		= sizeof(int),
6853 		.mode		= 0644,
6854 		.proc_handler	= proc_dointvec,
6855 	},
6856 	{
6857 		.procname	= "accept_ra_pinfo",
6858 		.data		= &ipv6_devconf.accept_ra_pinfo,
6859 		.maxlen		= sizeof(int),
6860 		.mode		= 0644,
6861 		.proc_handler	= proc_dointvec,
6862 	},
6863 #ifdef CONFIG_IPV6_ROUTER_PREF
6864 	{
6865 		.procname	= "accept_ra_rtr_pref",
6866 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6867 		.maxlen		= sizeof(int),
6868 		.mode		= 0644,
6869 		.proc_handler	= proc_dointvec,
6870 	},
6871 	{
6872 		.procname	= "router_probe_interval",
6873 		.data		= &ipv6_devconf.rtr_probe_interval,
6874 		.maxlen		= sizeof(int),
6875 		.mode		= 0644,
6876 		.proc_handler	= proc_dointvec_jiffies,
6877 	},
6878 #ifdef CONFIG_IPV6_ROUTE_INFO
6879 	{
6880 		.procname	= "accept_ra_rt_info_min_plen",
6881 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6882 		.maxlen		= sizeof(int),
6883 		.mode		= 0644,
6884 		.proc_handler	= proc_dointvec,
6885 	},
6886 	{
6887 		.procname	= "accept_ra_rt_info_max_plen",
6888 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6889 		.maxlen		= sizeof(int),
6890 		.mode		= 0644,
6891 		.proc_handler	= proc_dointvec,
6892 	},
6893 #endif
6894 #endif
6895 	{
6896 		.procname	= "proxy_ndp",
6897 		.data		= &ipv6_devconf.proxy_ndp,
6898 		.maxlen		= sizeof(int),
6899 		.mode		= 0644,
6900 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6901 	},
6902 	{
6903 		.procname	= "accept_source_route",
6904 		.data		= &ipv6_devconf.accept_source_route,
6905 		.maxlen		= sizeof(int),
6906 		.mode		= 0644,
6907 		.proc_handler	= proc_dointvec,
6908 	},
6909 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
6910 	{
6911 		.procname	= "optimistic_dad",
6912 		.data		= &ipv6_devconf.optimistic_dad,
6913 		.maxlen		= sizeof(int),
6914 		.mode		= 0644,
6915 		.proc_handler   = proc_dointvec,
6916 	},
6917 	{
6918 		.procname	= "use_optimistic",
6919 		.data		= &ipv6_devconf.use_optimistic,
6920 		.maxlen		= sizeof(int),
6921 		.mode		= 0644,
6922 		.proc_handler	= proc_dointvec,
6923 	},
6924 #endif
6925 #ifdef CONFIG_IPV6_MROUTE
6926 	{
6927 		.procname	= "mc_forwarding",
6928 		.data		= &ipv6_devconf.mc_forwarding,
6929 		.maxlen		= sizeof(int),
6930 		.mode		= 0444,
6931 		.proc_handler	= proc_dointvec,
6932 	},
6933 #endif
6934 	{
6935 		.procname	= "disable_ipv6",
6936 		.data		= &ipv6_devconf.disable_ipv6,
6937 		.maxlen		= sizeof(int),
6938 		.mode		= 0644,
6939 		.proc_handler	= addrconf_sysctl_disable,
6940 	},
6941 	{
6942 		.procname	= "accept_dad",
6943 		.data		= &ipv6_devconf.accept_dad,
6944 		.maxlen		= sizeof(int),
6945 		.mode		= 0644,
6946 		.proc_handler	= proc_dointvec,
6947 	},
6948 	{
6949 		.procname	= "force_tllao",
6950 		.data		= &ipv6_devconf.force_tllao,
6951 		.maxlen		= sizeof(int),
6952 		.mode		= 0644,
6953 		.proc_handler	= proc_dointvec
6954 	},
6955 	{
6956 		.procname	= "ndisc_notify",
6957 		.data		= &ipv6_devconf.ndisc_notify,
6958 		.maxlen		= sizeof(int),
6959 		.mode		= 0644,
6960 		.proc_handler	= proc_dointvec
6961 	},
6962 	{
6963 		.procname	= "suppress_frag_ndisc",
6964 		.data		= &ipv6_devconf.suppress_frag_ndisc,
6965 		.maxlen		= sizeof(int),
6966 		.mode		= 0644,
6967 		.proc_handler	= proc_dointvec
6968 	},
6969 	{
6970 		.procname	= "accept_ra_from_local",
6971 		.data		= &ipv6_devconf.accept_ra_from_local,
6972 		.maxlen		= sizeof(int),
6973 		.mode		= 0644,
6974 		.proc_handler	= proc_dointvec,
6975 	},
6976 	{
6977 		.procname	= "accept_ra_mtu",
6978 		.data		= &ipv6_devconf.accept_ra_mtu,
6979 		.maxlen		= sizeof(int),
6980 		.mode		= 0644,
6981 		.proc_handler	= proc_dointvec,
6982 	},
6983 	{
6984 		.procname	= "stable_secret",
6985 		.data		= &ipv6_devconf.stable_secret,
6986 		.maxlen		= IPV6_MAX_STRLEN,
6987 		.mode		= 0600,
6988 		.proc_handler	= addrconf_sysctl_stable_secret,
6989 	},
6990 	{
6991 		.procname	= "use_oif_addrs_only",
6992 		.data		= &ipv6_devconf.use_oif_addrs_only,
6993 		.maxlen		= sizeof(int),
6994 		.mode		= 0644,
6995 		.proc_handler	= proc_dointvec,
6996 	},
6997 	{
6998 		.procname	= "ignore_routes_with_linkdown",
6999 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
7000 		.maxlen		= sizeof(int),
7001 		.mode		= 0644,
7002 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
7003 	},
7004 	{
7005 		.procname	= "drop_unicast_in_l2_multicast",
7006 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
7007 		.maxlen		= sizeof(int),
7008 		.mode		= 0644,
7009 		.proc_handler	= proc_dointvec,
7010 	},
7011 	{
7012 		.procname	= "drop_unsolicited_na",
7013 		.data		= &ipv6_devconf.drop_unsolicited_na,
7014 		.maxlen		= sizeof(int),
7015 		.mode		= 0644,
7016 		.proc_handler	= proc_dointvec,
7017 	},
7018 	{
7019 		.procname	= "keep_addr_on_down",
7020 		.data		= &ipv6_devconf.keep_addr_on_down,
7021 		.maxlen		= sizeof(int),
7022 		.mode		= 0644,
7023 		.proc_handler	= proc_dointvec,
7024 
7025 	},
7026 	{
7027 		.procname	= "seg6_enabled",
7028 		.data		= &ipv6_devconf.seg6_enabled,
7029 		.maxlen		= sizeof(int),
7030 		.mode		= 0644,
7031 		.proc_handler	= proc_dointvec,
7032 	},
7033 #ifdef CONFIG_IPV6_SEG6_HMAC
7034 	{
7035 		.procname	= "seg6_require_hmac",
7036 		.data		= &ipv6_devconf.seg6_require_hmac,
7037 		.maxlen		= sizeof(int),
7038 		.mode		= 0644,
7039 		.proc_handler	= proc_dointvec,
7040 	},
7041 #endif
7042 	{
7043 		.procname       = "enhanced_dad",
7044 		.data           = &ipv6_devconf.enhanced_dad,
7045 		.maxlen         = sizeof(int),
7046 		.mode           = 0644,
7047 		.proc_handler   = proc_dointvec,
7048 	},
7049 	{
7050 		.procname	= "addr_gen_mode",
7051 		.data		= &ipv6_devconf.addr_gen_mode,
7052 		.maxlen		= sizeof(int),
7053 		.mode		= 0644,
7054 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
7055 	},
7056 	{
7057 		.procname       = "disable_policy",
7058 		.data           = &ipv6_devconf.disable_policy,
7059 		.maxlen         = sizeof(int),
7060 		.mode           = 0644,
7061 		.proc_handler   = addrconf_sysctl_disable_policy,
7062 	},
7063 	{
7064 		.procname	= "ndisc_tclass",
7065 		.data		= &ipv6_devconf.ndisc_tclass,
7066 		.maxlen		= sizeof(int),
7067 		.mode		= 0644,
7068 		.proc_handler	= proc_dointvec_minmax,
7069 		.extra1		= (void *)SYSCTL_ZERO,
7070 		.extra2		= (void *)&two_five_five,
7071 	},
7072 	{
7073 		.procname	= "rpl_seg_enabled",
7074 		.data		= &ipv6_devconf.rpl_seg_enabled,
7075 		.maxlen		= sizeof(int),
7076 		.mode		= 0644,
7077 		.proc_handler	= proc_dointvec,
7078 	},
7079 	{
7080 		.procname	= "ioam6_enabled",
7081 		.data		= &ipv6_devconf.ioam6_enabled,
7082 		.maxlen		= sizeof(u8),
7083 		.mode		= 0644,
7084 		.proc_handler	= proc_dou8vec_minmax,
7085 		.extra1		= (void *)SYSCTL_ZERO,
7086 		.extra2		= (void *)SYSCTL_ONE,
7087 	},
7088 	{
7089 		.procname	= "ioam6_id",
7090 		.data		= &ipv6_devconf.ioam6_id,
7091 		.maxlen		= sizeof(u32),
7092 		.mode		= 0644,
7093 		.proc_handler	= proc_douintvec_minmax,
7094 		.extra1		= (void *)SYSCTL_ZERO,
7095 		.extra2		= (void *)&ioam6_if_id_max,
7096 	},
7097 	{
7098 		.procname	= "ioam6_id_wide",
7099 		.data		= &ipv6_devconf.ioam6_id_wide,
7100 		.maxlen		= sizeof(u32),
7101 		.mode		= 0644,
7102 		.proc_handler	= proc_douintvec,
7103 	},
7104 	{
7105 		.procname	= "ndisc_evict_nocarrier",
7106 		.data		= &ipv6_devconf.ndisc_evict_nocarrier,
7107 		.maxlen		= sizeof(u8),
7108 		.mode		= 0644,
7109 		.proc_handler	= proc_dou8vec_minmax,
7110 		.extra1		= (void *)SYSCTL_ZERO,
7111 		.extra2		= (void *)SYSCTL_ONE,
7112 	},
7113 	{
7114 		.procname	= "accept_untracked_na",
7115 		.data		= &ipv6_devconf.accept_untracked_na,
7116 		.maxlen		= sizeof(int),
7117 		.mode		= 0644,
7118 		.proc_handler	= proc_dointvec_minmax,
7119 		.extra1		= SYSCTL_ZERO,
7120 		.extra2		= SYSCTL_TWO,
7121 	},
7122 	{
7123 		/* sentinel */
7124 	}
7125 };
7126 
7127 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
7128 		struct inet6_dev *idev, struct ipv6_devconf *p)
7129 {
7130 	int i, ifindex;
7131 	struct ctl_table *table;
7132 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
7133 
7134 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL_ACCOUNT);
7135 	if (!table)
7136 		goto out;
7137 
7138 	for (i = 0; table[i].data; i++) {
7139 		table[i].data += (char *)p - (char *)&ipv6_devconf;
7140 		/* If one of these is already set, then it is not safe to
7141 		 * overwrite either of them: this makes proc_dointvec_minmax
7142 		 * usable.
7143 		 */
7144 		if (!table[i].extra1 && !table[i].extra2) {
7145 			table[i].extra1 = idev; /* embedded; no ref */
7146 			table[i].extra2 = net;
7147 		}
7148 	}
7149 
7150 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
7151 
7152 	p->sysctl_header = register_net_sysctl_sz(net, path, table,
7153 						  ARRAY_SIZE(addrconf_sysctl));
7154 	if (!p->sysctl_header)
7155 		goto free;
7156 
7157 	if (!strcmp(dev_name, "all"))
7158 		ifindex = NETCONFA_IFINDEX_ALL;
7159 	else if (!strcmp(dev_name, "default"))
7160 		ifindex = NETCONFA_IFINDEX_DEFAULT;
7161 	else
7162 		ifindex = idev->dev->ifindex;
7163 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
7164 				     ifindex, p);
7165 	return 0;
7166 
7167 free:
7168 	kfree(table);
7169 out:
7170 	return -ENOBUFS;
7171 }
7172 
7173 static void __addrconf_sysctl_unregister(struct net *net,
7174 					 struct ipv6_devconf *p, int ifindex)
7175 {
7176 	struct ctl_table *table;
7177 
7178 	if (!p->sysctl_header)
7179 		return;
7180 
7181 	table = p->sysctl_header->ctl_table_arg;
7182 	unregister_net_sysctl_table(p->sysctl_header);
7183 	p->sysctl_header = NULL;
7184 	kfree(table);
7185 
7186 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
7187 }
7188 
7189 static int addrconf_sysctl_register(struct inet6_dev *idev)
7190 {
7191 	int err;
7192 
7193 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
7194 		return -EINVAL;
7195 
7196 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
7197 				    &ndisc_ifinfo_sysctl_change);
7198 	if (err)
7199 		return err;
7200 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
7201 					 idev, &idev->cnf);
7202 	if (err)
7203 		neigh_sysctl_unregister(idev->nd_parms);
7204 
7205 	return err;
7206 }
7207 
7208 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
7209 {
7210 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
7211 				     idev->dev->ifindex);
7212 	neigh_sysctl_unregister(idev->nd_parms);
7213 }
7214 
7215 
7216 #endif
7217 
7218 static int __net_init addrconf_init_net(struct net *net)
7219 {
7220 	int err = -ENOMEM;
7221 	struct ipv6_devconf *all, *dflt;
7222 
7223 	spin_lock_init(&net->ipv6.addrconf_hash_lock);
7224 	INIT_DEFERRABLE_WORK(&net->ipv6.addr_chk_work, addrconf_verify_work);
7225 	net->ipv6.inet6_addr_lst = kcalloc(IN6_ADDR_HSIZE,
7226 					   sizeof(struct hlist_head),
7227 					   GFP_KERNEL);
7228 	if (!net->ipv6.inet6_addr_lst)
7229 		goto err_alloc_addr;
7230 
7231 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
7232 	if (!all)
7233 		goto err_alloc_all;
7234 
7235 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
7236 	if (!dflt)
7237 		goto err_alloc_dflt;
7238 
7239 	if (!net_eq(net, &init_net)) {
7240 		switch (net_inherit_devconf()) {
7241 		case 1:  /* copy from init_net */
7242 			memcpy(all, init_net.ipv6.devconf_all,
7243 			       sizeof(ipv6_devconf));
7244 			memcpy(dflt, init_net.ipv6.devconf_dflt,
7245 			       sizeof(ipv6_devconf_dflt));
7246 			break;
7247 		case 3: /* copy from the current netns */
7248 			memcpy(all, current->nsproxy->net_ns->ipv6.devconf_all,
7249 			       sizeof(ipv6_devconf));
7250 			memcpy(dflt,
7251 			       current->nsproxy->net_ns->ipv6.devconf_dflt,
7252 			       sizeof(ipv6_devconf_dflt));
7253 			break;
7254 		case 0:
7255 		case 2:
7256 			/* use compiled values */
7257 			break;
7258 		}
7259 	}
7260 
7261 	/* these will be inherited by all namespaces */
7262 	dflt->autoconf = ipv6_defaults.autoconf;
7263 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
7264 
7265 	dflt->stable_secret.initialized = false;
7266 	all->stable_secret.initialized = false;
7267 
7268 	net->ipv6.devconf_all = all;
7269 	net->ipv6.devconf_dflt = dflt;
7270 
7271 #ifdef CONFIG_SYSCTL
7272 	err = __addrconf_sysctl_register(net, "all", NULL, all);
7273 	if (err < 0)
7274 		goto err_reg_all;
7275 
7276 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
7277 	if (err < 0)
7278 		goto err_reg_dflt;
7279 #endif
7280 	return 0;
7281 
7282 #ifdef CONFIG_SYSCTL
7283 err_reg_dflt:
7284 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
7285 err_reg_all:
7286 	kfree(dflt);
7287 	net->ipv6.devconf_dflt = NULL;
7288 #endif
7289 err_alloc_dflt:
7290 	kfree(all);
7291 	net->ipv6.devconf_all = NULL;
7292 err_alloc_all:
7293 	kfree(net->ipv6.inet6_addr_lst);
7294 err_alloc_addr:
7295 	return err;
7296 }
7297 
7298 static void __net_exit addrconf_exit_net(struct net *net)
7299 {
7300 	int i;
7301 
7302 #ifdef CONFIG_SYSCTL
7303 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
7304 				     NETCONFA_IFINDEX_DEFAULT);
7305 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
7306 				     NETCONFA_IFINDEX_ALL);
7307 #endif
7308 	kfree(net->ipv6.devconf_dflt);
7309 	net->ipv6.devconf_dflt = NULL;
7310 	kfree(net->ipv6.devconf_all);
7311 	net->ipv6.devconf_all = NULL;
7312 
7313 	cancel_delayed_work_sync(&net->ipv6.addr_chk_work);
7314 	/*
7315 	 *	Check hash table, then free it.
7316 	 */
7317 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7318 		WARN_ON_ONCE(!hlist_empty(&net->ipv6.inet6_addr_lst[i]));
7319 
7320 	kfree(net->ipv6.inet6_addr_lst);
7321 	net->ipv6.inet6_addr_lst = NULL;
7322 }
7323 
7324 static struct pernet_operations addrconf_ops = {
7325 	.init = addrconf_init_net,
7326 	.exit = addrconf_exit_net,
7327 };
7328 
7329 static struct rtnl_af_ops inet6_ops __read_mostly = {
7330 	.family		  = AF_INET6,
7331 	.fill_link_af	  = inet6_fill_link_af,
7332 	.get_link_af_size = inet6_get_link_af_size,
7333 	.validate_link_af = inet6_validate_link_af,
7334 	.set_link_af	  = inet6_set_link_af,
7335 };
7336 
7337 /*
7338  *	Init / cleanup code
7339  */
7340 
7341 int __init addrconf_init(void)
7342 {
7343 	struct inet6_dev *idev;
7344 	int err;
7345 
7346 	err = ipv6_addr_label_init();
7347 	if (err < 0) {
7348 		pr_crit("%s: cannot initialize default policy table: %d\n",
7349 			__func__, err);
7350 		goto out;
7351 	}
7352 
7353 	err = register_pernet_subsys(&addrconf_ops);
7354 	if (err < 0)
7355 		goto out_addrlabel;
7356 
7357 	addrconf_wq = create_workqueue("ipv6_addrconf");
7358 	if (!addrconf_wq) {
7359 		err = -ENOMEM;
7360 		goto out_nowq;
7361 	}
7362 
7363 	rtnl_lock();
7364 	idev = ipv6_add_dev(blackhole_netdev);
7365 	rtnl_unlock();
7366 	if (IS_ERR(idev)) {
7367 		err = PTR_ERR(idev);
7368 		goto errlo;
7369 	}
7370 
7371 	ip6_route_init_special_entries();
7372 
7373 	register_netdevice_notifier(&ipv6_dev_notf);
7374 
7375 	addrconf_verify(&init_net);
7376 
7377 	rtnl_af_register(&inet6_ops);
7378 
7379 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETLINK,
7380 				   NULL, inet6_dump_ifinfo, 0);
7381 	if (err < 0)
7382 		goto errout;
7383 
7384 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWADDR,
7385 				   inet6_rtm_newaddr, NULL, 0);
7386 	if (err < 0)
7387 		goto errout;
7388 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELADDR,
7389 				   inet6_rtm_deladdr, NULL, 0);
7390 	if (err < 0)
7391 		goto errout;
7392 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDR,
7393 				   inet6_rtm_getaddr, inet6_dump_ifaddr,
7394 				   RTNL_FLAG_DOIT_UNLOCKED);
7395 	if (err < 0)
7396 		goto errout;
7397 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETMULTICAST,
7398 				   NULL, inet6_dump_ifmcaddr, 0);
7399 	if (err < 0)
7400 		goto errout;
7401 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETANYCAST,
7402 				   NULL, inet6_dump_ifacaddr, 0);
7403 	if (err < 0)
7404 		goto errout;
7405 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETNETCONF,
7406 				   inet6_netconf_get_devconf,
7407 				   inet6_netconf_dump_devconf,
7408 				   RTNL_FLAG_DOIT_UNLOCKED);
7409 	if (err < 0)
7410 		goto errout;
7411 	err = ipv6_addr_label_rtnl_register();
7412 	if (err < 0)
7413 		goto errout;
7414 
7415 	return 0;
7416 errout:
7417 	rtnl_unregister_all(PF_INET6);
7418 	rtnl_af_unregister(&inet6_ops);
7419 	unregister_netdevice_notifier(&ipv6_dev_notf);
7420 errlo:
7421 	destroy_workqueue(addrconf_wq);
7422 out_nowq:
7423 	unregister_pernet_subsys(&addrconf_ops);
7424 out_addrlabel:
7425 	ipv6_addr_label_cleanup();
7426 out:
7427 	return err;
7428 }
7429 
7430 void addrconf_cleanup(void)
7431 {
7432 	struct net_device *dev;
7433 
7434 	unregister_netdevice_notifier(&ipv6_dev_notf);
7435 	unregister_pernet_subsys(&addrconf_ops);
7436 	ipv6_addr_label_cleanup();
7437 
7438 	rtnl_af_unregister(&inet6_ops);
7439 
7440 	rtnl_lock();
7441 
7442 	/* clean dev list */
7443 	for_each_netdev(&init_net, dev) {
7444 		if (__in6_dev_get(dev) == NULL)
7445 			continue;
7446 		addrconf_ifdown(dev, true);
7447 	}
7448 	addrconf_ifdown(init_net.loopback_dev, true);
7449 
7450 	rtnl_unlock();
7451 
7452 	destroy_workqueue(addrconf_wq);
7453 }
7454