xref: /openbmc/linux/net/ipv6/addrconf.c (revision adb19164)
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 				result = ifp;
2062 				in6_ifa_hold(ifp);
2063 				break;
2064 			}
2065 		}
2066 	}
2067 	rcu_read_unlock();
2068 
2069 	return result;
2070 }
2071 
2072 /* Gets referenced address, destroys ifaddr */
2073 
2074 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
2075 {
2076 	if (dad_failed)
2077 		ifp->flags |= IFA_F_DADFAILED;
2078 
2079 	if (ifp->flags&IFA_F_TEMPORARY) {
2080 		struct inet6_ifaddr *ifpub;
2081 		spin_lock_bh(&ifp->lock);
2082 		ifpub = ifp->ifpub;
2083 		if (ifpub) {
2084 			in6_ifa_hold(ifpub);
2085 			spin_unlock_bh(&ifp->lock);
2086 			ipv6_create_tempaddr(ifpub, true);
2087 			in6_ifa_put(ifpub);
2088 		} else {
2089 			spin_unlock_bh(&ifp->lock);
2090 		}
2091 		ipv6_del_addr(ifp);
2092 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
2093 		spin_lock_bh(&ifp->lock);
2094 		addrconf_del_dad_work(ifp);
2095 		ifp->flags |= IFA_F_TENTATIVE;
2096 		if (dad_failed)
2097 			ifp->flags &= ~IFA_F_OPTIMISTIC;
2098 		spin_unlock_bh(&ifp->lock);
2099 		if (dad_failed)
2100 			ipv6_ifa_notify(0, ifp);
2101 		in6_ifa_put(ifp);
2102 	} else {
2103 		ipv6_del_addr(ifp);
2104 	}
2105 }
2106 
2107 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
2108 {
2109 	int err = -ENOENT;
2110 
2111 	spin_lock_bh(&ifp->lock);
2112 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
2113 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
2114 		err = 0;
2115 	}
2116 	spin_unlock_bh(&ifp->lock);
2117 
2118 	return err;
2119 }
2120 
2121 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp)
2122 {
2123 	struct inet6_dev *idev = ifp->idev;
2124 	struct net *net = dev_net(idev->dev);
2125 
2126 	if (addrconf_dad_end(ifp)) {
2127 		in6_ifa_put(ifp);
2128 		return;
2129 	}
2130 
2131 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c used by %pM detected!\n",
2132 			     ifp->idev->dev->name, &ifp->addr, eth_hdr(skb)->h_source);
2133 
2134 	spin_lock_bh(&ifp->lock);
2135 
2136 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2137 		struct in6_addr new_addr;
2138 		struct inet6_ifaddr *ifp2;
2139 		int retries = ifp->stable_privacy_retry + 1;
2140 		struct ifa6_config cfg = {
2141 			.pfx = &new_addr,
2142 			.plen = ifp->prefix_len,
2143 			.ifa_flags = ifp->flags,
2144 			.valid_lft = ifp->valid_lft,
2145 			.preferred_lft = ifp->prefered_lft,
2146 			.scope = ifp->scope,
2147 		};
2148 
2149 		if (retries > net->ipv6.sysctl.idgen_retries) {
2150 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2151 					     ifp->idev->dev->name);
2152 			goto errdad;
2153 		}
2154 
2155 		new_addr = ifp->addr;
2156 		if (ipv6_generate_stable_address(&new_addr, retries,
2157 						 idev))
2158 			goto errdad;
2159 
2160 		spin_unlock_bh(&ifp->lock);
2161 
2162 		if (idev->cnf.max_addresses &&
2163 		    ipv6_count_addresses(idev) >=
2164 		    idev->cnf.max_addresses)
2165 			goto lock_errdad;
2166 
2167 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2168 				     ifp->idev->dev->name);
2169 
2170 		ifp2 = ipv6_add_addr(idev, &cfg, false, NULL);
2171 		if (IS_ERR(ifp2))
2172 			goto lock_errdad;
2173 
2174 		spin_lock_bh(&ifp2->lock);
2175 		ifp2->stable_privacy_retry = retries;
2176 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2177 		spin_unlock_bh(&ifp2->lock);
2178 
2179 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2180 		in6_ifa_put(ifp2);
2181 lock_errdad:
2182 		spin_lock_bh(&ifp->lock);
2183 	}
2184 
2185 errdad:
2186 	/* transition from _POSTDAD to _ERRDAD */
2187 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2188 	spin_unlock_bh(&ifp->lock);
2189 
2190 	addrconf_mod_dad_work(ifp, 0);
2191 	in6_ifa_put(ifp);
2192 }
2193 
2194 /* Join to solicited addr multicast group.
2195  * caller must hold RTNL */
2196 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2197 {
2198 	struct in6_addr maddr;
2199 
2200 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2201 		return;
2202 
2203 	addrconf_addr_solict_mult(addr, &maddr);
2204 	ipv6_dev_mc_inc(dev, &maddr);
2205 }
2206 
2207 /* caller must hold RTNL */
2208 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2209 {
2210 	struct in6_addr maddr;
2211 
2212 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2213 		return;
2214 
2215 	addrconf_addr_solict_mult(addr, &maddr);
2216 	__ipv6_dev_mc_dec(idev, &maddr);
2217 }
2218 
2219 /* caller must hold RTNL */
2220 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2221 {
2222 	struct in6_addr addr;
2223 
2224 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2225 		return;
2226 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2227 	if (ipv6_addr_any(&addr))
2228 		return;
2229 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2230 }
2231 
2232 /* caller must hold RTNL */
2233 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2234 {
2235 	struct in6_addr addr;
2236 
2237 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2238 		return;
2239 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2240 	if (ipv6_addr_any(&addr))
2241 		return;
2242 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2243 }
2244 
2245 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2246 {
2247 	switch (dev->addr_len) {
2248 	case ETH_ALEN:
2249 		memcpy(eui, dev->dev_addr, 3);
2250 		eui[3] = 0xFF;
2251 		eui[4] = 0xFE;
2252 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2253 		break;
2254 	case EUI64_ADDR_LEN:
2255 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2256 		eui[0] ^= 2;
2257 		break;
2258 	default:
2259 		return -1;
2260 	}
2261 
2262 	return 0;
2263 }
2264 
2265 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2266 {
2267 	const union fwnet_hwaddr *ha;
2268 
2269 	if (dev->addr_len != FWNET_ALEN)
2270 		return -1;
2271 
2272 	ha = (const union fwnet_hwaddr *)dev->dev_addr;
2273 
2274 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2275 	eui[0] ^= 2;
2276 	return 0;
2277 }
2278 
2279 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2280 {
2281 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2282 	if (dev->addr_len != ARCNET_ALEN)
2283 		return -1;
2284 	memset(eui, 0, 7);
2285 	eui[7] = *(u8 *)dev->dev_addr;
2286 	return 0;
2287 }
2288 
2289 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2290 {
2291 	if (dev->addr_len != INFINIBAND_ALEN)
2292 		return -1;
2293 	memcpy(eui, dev->dev_addr + 12, 8);
2294 	eui[0] |= 2;
2295 	return 0;
2296 }
2297 
2298 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2299 {
2300 	if (addr == 0)
2301 		return -1;
2302 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2303 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2304 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2305 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2306 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2307 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2308 	eui[1] = 0;
2309 	eui[2] = 0x5E;
2310 	eui[3] = 0xFE;
2311 	memcpy(eui + 4, &addr, 4);
2312 	return 0;
2313 }
2314 
2315 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2316 {
2317 	if (dev->priv_flags & IFF_ISATAP)
2318 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2319 	return -1;
2320 }
2321 
2322 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2323 {
2324 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2325 }
2326 
2327 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2328 {
2329 	memcpy(eui, dev->perm_addr, 3);
2330 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2331 	eui[3] = 0xFF;
2332 	eui[4] = 0xFE;
2333 	eui[0] ^= 2;
2334 	return 0;
2335 }
2336 
2337 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2338 {
2339 	switch (dev->type) {
2340 	case ARPHRD_ETHER:
2341 	case ARPHRD_FDDI:
2342 		return addrconf_ifid_eui48(eui, dev);
2343 	case ARPHRD_ARCNET:
2344 		return addrconf_ifid_arcnet(eui, dev);
2345 	case ARPHRD_INFINIBAND:
2346 		return addrconf_ifid_infiniband(eui, dev);
2347 	case ARPHRD_SIT:
2348 		return addrconf_ifid_sit(eui, dev);
2349 	case ARPHRD_IPGRE:
2350 	case ARPHRD_TUNNEL:
2351 		return addrconf_ifid_gre(eui, dev);
2352 	case ARPHRD_6LOWPAN:
2353 		return addrconf_ifid_6lowpan(eui, dev);
2354 	case ARPHRD_IEEE1394:
2355 		return addrconf_ifid_ieee1394(eui, dev);
2356 	case ARPHRD_TUNNEL6:
2357 	case ARPHRD_IP6GRE:
2358 	case ARPHRD_RAWIP:
2359 		return addrconf_ifid_ip6tnl(eui, dev);
2360 	}
2361 	return -1;
2362 }
2363 
2364 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2365 {
2366 	int err = -1;
2367 	struct inet6_ifaddr *ifp;
2368 
2369 	read_lock_bh(&idev->lock);
2370 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2371 		if (ifp->scope > IFA_LINK)
2372 			break;
2373 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2374 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2375 			err = 0;
2376 			break;
2377 		}
2378 	}
2379 	read_unlock_bh(&idev->lock);
2380 	return err;
2381 }
2382 
2383 /* Generation of a randomized Interface Identifier
2384  * draft-ietf-6man-rfc4941bis, Section 3.3.1
2385  */
2386 
2387 static void ipv6_gen_rnd_iid(struct in6_addr *addr)
2388 {
2389 regen:
2390 	get_random_bytes(&addr->s6_addr[8], 8);
2391 
2392 	/* <draft-ietf-6man-rfc4941bis-08.txt>, Section 3.3.1:
2393 	 * check if generated address is not inappropriate:
2394 	 *
2395 	 * - Reserved IPv6 Interface Identifiers
2396 	 * - XXX: already assigned to an address on the device
2397 	 */
2398 
2399 	/* Subnet-router anycast: 0000:0000:0000:0000 */
2400 	if (!(addr->s6_addr32[2] | addr->s6_addr32[3]))
2401 		goto regen;
2402 
2403 	/* IANA Ethernet block: 0200:5EFF:FE00:0000-0200:5EFF:FE00:5212
2404 	 * Proxy Mobile IPv6:   0200:5EFF:FE00:5213
2405 	 * IANA Ethernet block: 0200:5EFF:FE00:5214-0200:5EFF:FEFF:FFFF
2406 	 */
2407 	if (ntohl(addr->s6_addr32[2]) == 0x02005eff &&
2408 	    (ntohl(addr->s6_addr32[3]) & 0Xff000000) == 0xfe000000)
2409 		goto regen;
2410 
2411 	/* Reserved subnet anycast addresses */
2412 	if (ntohl(addr->s6_addr32[2]) == 0xfdffffff &&
2413 	    ntohl(addr->s6_addr32[3]) >= 0Xffffff80)
2414 		goto regen;
2415 }
2416 
2417 /*
2418  *	Add prefix route.
2419  */
2420 
2421 static void
2422 addrconf_prefix_route(struct in6_addr *pfx, int plen, u32 metric,
2423 		      struct net_device *dev, unsigned long expires,
2424 		      u32 flags, gfp_t gfp_flags)
2425 {
2426 	struct fib6_config cfg = {
2427 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2428 		.fc_metric = metric ? : IP6_RT_PRIO_ADDRCONF,
2429 		.fc_ifindex = dev->ifindex,
2430 		.fc_expires = expires,
2431 		.fc_dst_len = plen,
2432 		.fc_flags = RTF_UP | flags,
2433 		.fc_nlinfo.nl_net = dev_net(dev),
2434 		.fc_protocol = RTPROT_KERNEL,
2435 		.fc_type = RTN_UNICAST,
2436 	};
2437 
2438 	cfg.fc_dst = *pfx;
2439 
2440 	/* Prevent useless cloning on PtP SIT.
2441 	   This thing is done here expecting that the whole
2442 	   class of non-broadcast devices need not cloning.
2443 	 */
2444 #if IS_ENABLED(CONFIG_IPV6_SIT)
2445 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2446 		cfg.fc_flags |= RTF_NONEXTHOP;
2447 #endif
2448 
2449 	ip6_route_add(&cfg, gfp_flags, NULL);
2450 }
2451 
2452 
2453 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2454 						  int plen,
2455 						  const struct net_device *dev,
2456 						  u32 flags, u32 noflags,
2457 						  bool no_gw)
2458 {
2459 	struct fib6_node *fn;
2460 	struct fib6_info *rt = NULL;
2461 	struct fib6_table *table;
2462 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2463 
2464 	table = fib6_get_table(dev_net(dev), tb_id);
2465 	if (!table)
2466 		return NULL;
2467 
2468 	rcu_read_lock();
2469 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2470 	if (!fn)
2471 		goto out;
2472 
2473 	for_each_fib6_node_rt_rcu(fn) {
2474 		/* prefix routes only use builtin fib6_nh */
2475 		if (rt->nh)
2476 			continue;
2477 
2478 		if (rt->fib6_nh->fib_nh_dev->ifindex != dev->ifindex)
2479 			continue;
2480 		if (no_gw && rt->fib6_nh->fib_nh_gw_family)
2481 			continue;
2482 		if ((rt->fib6_flags & flags) != flags)
2483 			continue;
2484 		if ((rt->fib6_flags & noflags) != 0)
2485 			continue;
2486 		if (!fib6_info_hold_safe(rt))
2487 			continue;
2488 		break;
2489 	}
2490 out:
2491 	rcu_read_unlock();
2492 	return rt;
2493 }
2494 
2495 
2496 /* Create "default" multicast route to the interface */
2497 
2498 static void addrconf_add_mroute(struct net_device *dev)
2499 {
2500 	struct fib6_config cfg = {
2501 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2502 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2503 		.fc_ifindex = dev->ifindex,
2504 		.fc_dst_len = 8,
2505 		.fc_flags = RTF_UP,
2506 		.fc_type = RTN_MULTICAST,
2507 		.fc_nlinfo.nl_net = dev_net(dev),
2508 		.fc_protocol = RTPROT_KERNEL,
2509 	};
2510 
2511 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2512 
2513 	ip6_route_add(&cfg, GFP_KERNEL, NULL);
2514 }
2515 
2516 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2517 {
2518 	struct inet6_dev *idev;
2519 
2520 	ASSERT_RTNL();
2521 
2522 	idev = ipv6_find_idev(dev);
2523 	if (IS_ERR(idev))
2524 		return idev;
2525 
2526 	if (idev->cnf.disable_ipv6)
2527 		return ERR_PTR(-EACCES);
2528 
2529 	/* Add default multicast route */
2530 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2531 		addrconf_add_mroute(dev);
2532 
2533 	return idev;
2534 }
2535 
2536 static void manage_tempaddrs(struct inet6_dev *idev,
2537 			     struct inet6_ifaddr *ifp,
2538 			     __u32 valid_lft, __u32 prefered_lft,
2539 			     bool create, unsigned long now)
2540 {
2541 	u32 flags;
2542 	struct inet6_ifaddr *ift;
2543 
2544 	read_lock_bh(&idev->lock);
2545 	/* update all temporary addresses in the list */
2546 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2547 		int age, max_valid, max_prefered;
2548 
2549 		if (ifp != ift->ifpub)
2550 			continue;
2551 
2552 		/* RFC 4941 section 3.3:
2553 		 * If a received option will extend the lifetime of a public
2554 		 * address, the lifetimes of temporary addresses should
2555 		 * be extended, subject to the overall constraint that no
2556 		 * temporary addresses should ever remain "valid" or "preferred"
2557 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2558 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2559 		 */
2560 		age = (now - ift->cstamp) / HZ;
2561 		max_valid = idev->cnf.temp_valid_lft - age;
2562 		if (max_valid < 0)
2563 			max_valid = 0;
2564 
2565 		max_prefered = idev->cnf.temp_prefered_lft -
2566 			       idev->desync_factor - age;
2567 		if (max_prefered < 0)
2568 			max_prefered = 0;
2569 
2570 		if (valid_lft > max_valid)
2571 			valid_lft = max_valid;
2572 
2573 		if (prefered_lft > max_prefered)
2574 			prefered_lft = max_prefered;
2575 
2576 		spin_lock(&ift->lock);
2577 		flags = ift->flags;
2578 		ift->valid_lft = valid_lft;
2579 		ift->prefered_lft = prefered_lft;
2580 		ift->tstamp = now;
2581 		if (prefered_lft > 0)
2582 			ift->flags &= ~IFA_F_DEPRECATED;
2583 
2584 		spin_unlock(&ift->lock);
2585 		if (!(flags&IFA_F_TENTATIVE))
2586 			ipv6_ifa_notify(0, ift);
2587 	}
2588 
2589 	/* Also create a temporary address if it's enabled but no temporary
2590 	 * address currently exists.
2591 	 * However, we get called with valid_lft == 0, prefered_lft == 0, create == false
2592 	 * as part of cleanup (ie. deleting the mngtmpaddr).
2593 	 * We don't want that to result in creating a new temporary ip address.
2594 	 */
2595 	if (list_empty(&idev->tempaddr_list) && (valid_lft || prefered_lft))
2596 		create = true;
2597 
2598 	if (create && idev->cnf.use_tempaddr > 0) {
2599 		/* When a new public address is created as described
2600 		 * in [ADDRCONF], also create a new temporary address.
2601 		 */
2602 		read_unlock_bh(&idev->lock);
2603 		ipv6_create_tempaddr(ifp, false);
2604 	} else {
2605 		read_unlock_bh(&idev->lock);
2606 	}
2607 }
2608 
2609 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2610 {
2611 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2612 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2613 }
2614 
2615 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2616 				 const struct prefix_info *pinfo,
2617 				 struct inet6_dev *in6_dev,
2618 				 const struct in6_addr *addr, int addr_type,
2619 				 u32 addr_flags, bool sllao, bool tokenized,
2620 				 __u32 valid_lft, u32 prefered_lft)
2621 {
2622 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2623 	int create = 0, update_lft = 0;
2624 
2625 	if (!ifp && valid_lft) {
2626 		int max_addresses = in6_dev->cnf.max_addresses;
2627 		struct ifa6_config cfg = {
2628 			.pfx = addr,
2629 			.plen = pinfo->prefix_len,
2630 			.ifa_flags = addr_flags,
2631 			.valid_lft = valid_lft,
2632 			.preferred_lft = prefered_lft,
2633 			.scope = addr_type & IPV6_ADDR_SCOPE_MASK,
2634 			.ifa_proto = IFAPROT_KERNEL_RA
2635 		};
2636 
2637 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2638 		if ((net->ipv6.devconf_all->optimistic_dad ||
2639 		     in6_dev->cnf.optimistic_dad) &&
2640 		    !net->ipv6.devconf_all->forwarding && sllao)
2641 			cfg.ifa_flags |= IFA_F_OPTIMISTIC;
2642 #endif
2643 
2644 		/* Do not allow to create too much of autoconfigured
2645 		 * addresses; this would be too easy way to crash kernel.
2646 		 */
2647 		if (!max_addresses ||
2648 		    ipv6_count_addresses(in6_dev) < max_addresses)
2649 			ifp = ipv6_add_addr(in6_dev, &cfg, false, NULL);
2650 
2651 		if (IS_ERR_OR_NULL(ifp))
2652 			return -1;
2653 
2654 		create = 1;
2655 		spin_lock_bh(&ifp->lock);
2656 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2657 		ifp->cstamp = jiffies;
2658 		ifp->tokenized = tokenized;
2659 		spin_unlock_bh(&ifp->lock);
2660 		addrconf_dad_start(ifp);
2661 	}
2662 
2663 	if (ifp) {
2664 		u32 flags;
2665 		unsigned long now;
2666 		u32 stored_lft;
2667 
2668 		/* update lifetime (RFC2462 5.5.3 e) */
2669 		spin_lock_bh(&ifp->lock);
2670 		now = jiffies;
2671 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2672 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2673 		else
2674 			stored_lft = 0;
2675 		if (!create && stored_lft) {
2676 			const u32 minimum_lft = min_t(u32,
2677 				stored_lft, MIN_VALID_LIFETIME);
2678 			valid_lft = max(valid_lft, minimum_lft);
2679 
2680 			/* RFC4862 Section 5.5.3e:
2681 			 * "Note that the preferred lifetime of the
2682 			 *  corresponding address is always reset to
2683 			 *  the Preferred Lifetime in the received
2684 			 *  Prefix Information option, regardless of
2685 			 *  whether the valid lifetime is also reset or
2686 			 *  ignored."
2687 			 *
2688 			 * So we should always update prefered_lft here.
2689 			 */
2690 			update_lft = 1;
2691 		}
2692 
2693 		if (update_lft) {
2694 			ifp->valid_lft = valid_lft;
2695 			ifp->prefered_lft = prefered_lft;
2696 			ifp->tstamp = now;
2697 			flags = ifp->flags;
2698 			ifp->flags &= ~IFA_F_DEPRECATED;
2699 			spin_unlock_bh(&ifp->lock);
2700 
2701 			if (!(flags&IFA_F_TENTATIVE))
2702 				ipv6_ifa_notify(0, ifp);
2703 		} else
2704 			spin_unlock_bh(&ifp->lock);
2705 
2706 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2707 				 create, now);
2708 
2709 		in6_ifa_put(ifp);
2710 		addrconf_verify(net);
2711 	}
2712 
2713 	return 0;
2714 }
2715 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2716 
2717 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2718 {
2719 	struct prefix_info *pinfo;
2720 	__u32 valid_lft;
2721 	__u32 prefered_lft;
2722 	int addr_type, err;
2723 	u32 addr_flags = 0;
2724 	struct inet6_dev *in6_dev;
2725 	struct net *net = dev_net(dev);
2726 
2727 	pinfo = (struct prefix_info *) opt;
2728 
2729 	if (len < sizeof(struct prefix_info)) {
2730 		netdev_dbg(dev, "addrconf: prefix option too short\n");
2731 		return;
2732 	}
2733 
2734 	/*
2735 	 *	Validation checks ([ADDRCONF], page 19)
2736 	 */
2737 
2738 	addr_type = ipv6_addr_type(&pinfo->prefix);
2739 
2740 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2741 		return;
2742 
2743 	valid_lft = ntohl(pinfo->valid);
2744 	prefered_lft = ntohl(pinfo->prefered);
2745 
2746 	if (prefered_lft > valid_lft) {
2747 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2748 		return;
2749 	}
2750 
2751 	in6_dev = in6_dev_get(dev);
2752 
2753 	if (!in6_dev) {
2754 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2755 				    dev->name);
2756 		return;
2757 	}
2758 
2759 	if (valid_lft != 0 && valid_lft < in6_dev->cnf.accept_ra_min_lft)
2760 		goto put;
2761 
2762 	/*
2763 	 *	Two things going on here:
2764 	 *	1) Add routes for on-link prefixes
2765 	 *	2) Configure prefixes with the auto flag set
2766 	 */
2767 
2768 	if (pinfo->onlink) {
2769 		struct fib6_info *rt;
2770 		unsigned long rt_expires;
2771 
2772 		/* Avoid arithmetic overflow. Really, we could
2773 		 * save rt_expires in seconds, likely valid_lft,
2774 		 * but it would require division in fib gc, that it
2775 		 * not good.
2776 		 */
2777 		if (HZ > USER_HZ)
2778 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2779 		else
2780 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2781 
2782 		if (addrconf_finite_timeout(rt_expires))
2783 			rt_expires *= HZ;
2784 
2785 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2786 					       pinfo->prefix_len,
2787 					       dev,
2788 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2789 					       RTF_DEFAULT, true);
2790 
2791 		if (rt) {
2792 			/* Autoconf prefix route */
2793 			if (valid_lft == 0) {
2794 				ip6_del_rt(net, rt, false);
2795 				rt = NULL;
2796 			} else if (addrconf_finite_timeout(rt_expires)) {
2797 				/* not infinity */
2798 				fib6_set_expires(rt, jiffies + rt_expires);
2799 			} else {
2800 				fib6_clean_expires(rt);
2801 			}
2802 		} else if (valid_lft) {
2803 			clock_t expires = 0;
2804 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2805 			if (addrconf_finite_timeout(rt_expires)) {
2806 				/* not infinity */
2807 				flags |= RTF_EXPIRES;
2808 				expires = jiffies_to_clock_t(rt_expires);
2809 			}
2810 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2811 					      0, dev, expires, flags,
2812 					      GFP_ATOMIC);
2813 		}
2814 		fib6_info_release(rt);
2815 	}
2816 
2817 	/* Try to figure out our local address for this prefix */
2818 
2819 	if (pinfo->autoconf && in6_dev->cnf.autoconf) {
2820 		struct in6_addr addr;
2821 		bool tokenized = false, dev_addr_generated = false;
2822 
2823 		if (pinfo->prefix_len == 64) {
2824 			memcpy(&addr, &pinfo->prefix, 8);
2825 
2826 			if (!ipv6_addr_any(&in6_dev->token)) {
2827 				read_lock_bh(&in6_dev->lock);
2828 				memcpy(addr.s6_addr + 8,
2829 				       in6_dev->token.s6_addr + 8, 8);
2830 				read_unlock_bh(&in6_dev->lock);
2831 				tokenized = true;
2832 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2833 				   !ipv6_generate_stable_address(&addr, 0,
2834 								 in6_dev)) {
2835 				addr_flags |= IFA_F_STABLE_PRIVACY;
2836 				goto ok;
2837 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2838 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2839 				goto put;
2840 			} else {
2841 				dev_addr_generated = true;
2842 			}
2843 			goto ok;
2844 		}
2845 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2846 				    pinfo->prefix_len);
2847 		goto put;
2848 
2849 ok:
2850 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2851 						   &addr, addr_type,
2852 						   addr_flags, sllao,
2853 						   tokenized, valid_lft,
2854 						   prefered_lft);
2855 		if (err)
2856 			goto put;
2857 
2858 		/* Ignore error case here because previous prefix add addr was
2859 		 * successful which will be notified.
2860 		 */
2861 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2862 					      addr_type, addr_flags, sllao,
2863 					      tokenized, valid_lft,
2864 					      prefered_lft,
2865 					      dev_addr_generated);
2866 	}
2867 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2868 put:
2869 	in6_dev_put(in6_dev);
2870 }
2871 
2872 static int addrconf_set_sit_dstaddr(struct net *net, struct net_device *dev,
2873 		struct in6_ifreq *ireq)
2874 {
2875 	struct ip_tunnel_parm p = { };
2876 	int err;
2877 
2878 	if (!(ipv6_addr_type(&ireq->ifr6_addr) & IPV6_ADDR_COMPATv4))
2879 		return -EADDRNOTAVAIL;
2880 
2881 	p.iph.daddr = ireq->ifr6_addr.s6_addr32[3];
2882 	p.iph.version = 4;
2883 	p.iph.ihl = 5;
2884 	p.iph.protocol = IPPROTO_IPV6;
2885 	p.iph.ttl = 64;
2886 
2887 	if (!dev->netdev_ops->ndo_tunnel_ctl)
2888 		return -EOPNOTSUPP;
2889 	err = dev->netdev_ops->ndo_tunnel_ctl(dev, &p, SIOCADDTUNNEL);
2890 	if (err)
2891 		return err;
2892 
2893 	dev = __dev_get_by_name(net, p.name);
2894 	if (!dev)
2895 		return -ENOBUFS;
2896 	return dev_open(dev, NULL);
2897 }
2898 
2899 /*
2900  *	Set destination address.
2901  *	Special case for SIT interfaces where we create a new "virtual"
2902  *	device.
2903  */
2904 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2905 {
2906 	struct net_device *dev;
2907 	struct in6_ifreq ireq;
2908 	int err = -ENODEV;
2909 
2910 	if (!IS_ENABLED(CONFIG_IPV6_SIT))
2911 		return -ENODEV;
2912 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2913 		return -EFAULT;
2914 
2915 	rtnl_lock();
2916 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2917 	if (dev && dev->type == ARPHRD_SIT)
2918 		err = addrconf_set_sit_dstaddr(net, dev, &ireq);
2919 	rtnl_unlock();
2920 	return err;
2921 }
2922 
2923 static int ipv6_mc_config(struct sock *sk, bool join,
2924 			  const struct in6_addr *addr, int ifindex)
2925 {
2926 	int ret;
2927 
2928 	ASSERT_RTNL();
2929 
2930 	lock_sock(sk);
2931 	if (join)
2932 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2933 	else
2934 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2935 	release_sock(sk);
2936 
2937 	return ret;
2938 }
2939 
2940 /*
2941  *	Manual configuration of address on an interface
2942  */
2943 static int inet6_addr_add(struct net *net, int ifindex,
2944 			  struct ifa6_config *cfg,
2945 			  struct netlink_ext_ack *extack)
2946 {
2947 	struct inet6_ifaddr *ifp;
2948 	struct inet6_dev *idev;
2949 	struct net_device *dev;
2950 	unsigned long timeout;
2951 	clock_t expires;
2952 	u32 flags;
2953 
2954 	ASSERT_RTNL();
2955 
2956 	if (cfg->plen > 128) {
2957 		NL_SET_ERR_MSG_MOD(extack, "Invalid prefix length");
2958 		return -EINVAL;
2959 	}
2960 
2961 	/* check the lifetime */
2962 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft) {
2963 		NL_SET_ERR_MSG_MOD(extack, "address lifetime invalid");
2964 		return -EINVAL;
2965 	}
2966 
2967 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR && cfg->plen != 64) {
2968 		NL_SET_ERR_MSG_MOD(extack, "address with \"mngtmpaddr\" flag must have a prefix length of 64");
2969 		return -EINVAL;
2970 	}
2971 
2972 	dev = __dev_get_by_index(net, ifindex);
2973 	if (!dev)
2974 		return -ENODEV;
2975 
2976 	idev = addrconf_add_dev(dev);
2977 	if (IS_ERR(idev)) {
2978 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
2979 		return PTR_ERR(idev);
2980 	}
2981 
2982 	if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
2983 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
2984 					 true, cfg->pfx, ifindex);
2985 
2986 		if (ret < 0) {
2987 			NL_SET_ERR_MSG_MOD(extack, "Multicast auto join failed");
2988 			return ret;
2989 		}
2990 	}
2991 
2992 	cfg->scope = ipv6_addr_scope(cfg->pfx);
2993 
2994 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
2995 	if (addrconf_finite_timeout(timeout)) {
2996 		expires = jiffies_to_clock_t(timeout * HZ);
2997 		cfg->valid_lft = timeout;
2998 		flags = RTF_EXPIRES;
2999 	} else {
3000 		expires = 0;
3001 		flags = 0;
3002 		cfg->ifa_flags |= IFA_F_PERMANENT;
3003 	}
3004 
3005 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
3006 	if (addrconf_finite_timeout(timeout)) {
3007 		if (timeout == 0)
3008 			cfg->ifa_flags |= IFA_F_DEPRECATED;
3009 		cfg->preferred_lft = timeout;
3010 	}
3011 
3012 	ifp = ipv6_add_addr(idev, cfg, true, extack);
3013 	if (!IS_ERR(ifp)) {
3014 		if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
3015 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3016 					      ifp->rt_priority, dev, expires,
3017 					      flags, GFP_KERNEL);
3018 		}
3019 
3020 		/* Send a netlink notification if DAD is enabled and
3021 		 * optimistic flag is not set
3022 		 */
3023 		if (!(ifp->flags & (IFA_F_OPTIMISTIC | IFA_F_NODAD)))
3024 			ipv6_ifa_notify(0, ifp);
3025 		/*
3026 		 * Note that section 3.1 of RFC 4429 indicates
3027 		 * that the Optimistic flag should not be set for
3028 		 * manually configured addresses
3029 		 */
3030 		addrconf_dad_start(ifp);
3031 		if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR)
3032 			manage_tempaddrs(idev, ifp, cfg->valid_lft,
3033 					 cfg->preferred_lft, true, jiffies);
3034 		in6_ifa_put(ifp);
3035 		addrconf_verify_rtnl(net);
3036 		return 0;
3037 	} else if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
3038 		ipv6_mc_config(net->ipv6.mc_autojoin_sk, false,
3039 			       cfg->pfx, ifindex);
3040 	}
3041 
3042 	return PTR_ERR(ifp);
3043 }
3044 
3045 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
3046 			  const struct in6_addr *pfx, unsigned int plen,
3047 			  struct netlink_ext_ack *extack)
3048 {
3049 	struct inet6_ifaddr *ifp;
3050 	struct inet6_dev *idev;
3051 	struct net_device *dev;
3052 
3053 	if (plen > 128) {
3054 		NL_SET_ERR_MSG_MOD(extack, "Invalid prefix length");
3055 		return -EINVAL;
3056 	}
3057 
3058 	dev = __dev_get_by_index(net, ifindex);
3059 	if (!dev) {
3060 		NL_SET_ERR_MSG_MOD(extack, "Unable to find the interface");
3061 		return -ENODEV;
3062 	}
3063 
3064 	idev = __in6_dev_get(dev);
3065 	if (!idev) {
3066 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
3067 		return -ENXIO;
3068 	}
3069 
3070 	read_lock_bh(&idev->lock);
3071 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3072 		if (ifp->prefix_len == plen &&
3073 		    ipv6_addr_equal(pfx, &ifp->addr)) {
3074 			in6_ifa_hold(ifp);
3075 			read_unlock_bh(&idev->lock);
3076 
3077 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
3078 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
3079 				manage_tempaddrs(idev, ifp, 0, 0, false,
3080 						 jiffies);
3081 			ipv6_del_addr(ifp);
3082 			addrconf_verify_rtnl(net);
3083 			if (ipv6_addr_is_multicast(pfx)) {
3084 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3085 					       false, pfx, dev->ifindex);
3086 			}
3087 			return 0;
3088 		}
3089 	}
3090 	read_unlock_bh(&idev->lock);
3091 
3092 	NL_SET_ERR_MSG_MOD(extack, "address not found");
3093 	return -EADDRNOTAVAIL;
3094 }
3095 
3096 
3097 int addrconf_add_ifaddr(struct net *net, void __user *arg)
3098 {
3099 	struct ifa6_config cfg = {
3100 		.ifa_flags = IFA_F_PERMANENT,
3101 		.preferred_lft = INFINITY_LIFE_TIME,
3102 		.valid_lft = INFINITY_LIFE_TIME,
3103 	};
3104 	struct in6_ifreq ireq;
3105 	int err;
3106 
3107 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3108 		return -EPERM;
3109 
3110 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3111 		return -EFAULT;
3112 
3113 	cfg.pfx = &ireq.ifr6_addr;
3114 	cfg.plen = ireq.ifr6_prefixlen;
3115 
3116 	rtnl_lock();
3117 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &cfg, NULL);
3118 	rtnl_unlock();
3119 	return err;
3120 }
3121 
3122 int addrconf_del_ifaddr(struct net *net, void __user *arg)
3123 {
3124 	struct in6_ifreq ireq;
3125 	int err;
3126 
3127 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3128 		return -EPERM;
3129 
3130 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3131 		return -EFAULT;
3132 
3133 	rtnl_lock();
3134 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
3135 			     ireq.ifr6_prefixlen, NULL);
3136 	rtnl_unlock();
3137 	return err;
3138 }
3139 
3140 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
3141 		     int plen, int scope, u8 proto)
3142 {
3143 	struct inet6_ifaddr *ifp;
3144 	struct ifa6_config cfg = {
3145 		.pfx = addr,
3146 		.plen = plen,
3147 		.ifa_flags = IFA_F_PERMANENT,
3148 		.valid_lft = INFINITY_LIFE_TIME,
3149 		.preferred_lft = INFINITY_LIFE_TIME,
3150 		.scope = scope,
3151 		.ifa_proto = proto
3152 	};
3153 
3154 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3155 	if (!IS_ERR(ifp)) {
3156 		spin_lock_bh(&ifp->lock);
3157 		ifp->flags &= ~IFA_F_TENTATIVE;
3158 		spin_unlock_bh(&ifp->lock);
3159 		rt_genid_bump_ipv6(dev_net(idev->dev));
3160 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3161 		in6_ifa_put(ifp);
3162 	}
3163 }
3164 
3165 #if IS_ENABLED(CONFIG_IPV6_SIT) || IS_ENABLED(CONFIG_NET_IPGRE) || IS_ENABLED(CONFIG_IPV6_GRE)
3166 static void add_v4_addrs(struct inet6_dev *idev)
3167 {
3168 	struct in6_addr addr;
3169 	struct net_device *dev;
3170 	struct net *net = dev_net(idev->dev);
3171 	int scope, plen, offset = 0;
3172 	u32 pflags = 0;
3173 
3174 	ASSERT_RTNL();
3175 
3176 	memset(&addr, 0, sizeof(struct in6_addr));
3177 	/* in case of IP6GRE the dev_addr is an IPv6 and therefore we use only the last 4 bytes */
3178 	if (idev->dev->addr_len == sizeof(struct in6_addr))
3179 		offset = sizeof(struct in6_addr) - 4;
3180 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr + offset, 4);
3181 
3182 	if (!(idev->dev->flags & IFF_POINTOPOINT) && idev->dev->type == ARPHRD_SIT) {
3183 		scope = IPV6_ADDR_COMPATv4;
3184 		plen = 96;
3185 		pflags |= RTF_NONEXTHOP;
3186 	} else {
3187 		if (idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_NONE)
3188 			return;
3189 
3190 		addr.s6_addr32[0] = htonl(0xfe800000);
3191 		scope = IFA_LINK;
3192 		plen = 64;
3193 	}
3194 
3195 	if (addr.s6_addr32[3]) {
3196 		add_addr(idev, &addr, plen, scope, IFAPROT_UNSPEC);
3197 		addrconf_prefix_route(&addr, plen, 0, idev->dev, 0, pflags,
3198 				      GFP_KERNEL);
3199 		return;
3200 	}
3201 
3202 	for_each_netdev(net, dev) {
3203 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3204 		if (in_dev && (dev->flags & IFF_UP)) {
3205 			struct in_ifaddr *ifa;
3206 			int flag = scope;
3207 
3208 			in_dev_for_each_ifa_rtnl(ifa, in_dev) {
3209 				addr.s6_addr32[3] = ifa->ifa_local;
3210 
3211 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3212 					continue;
3213 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3214 					if (idev->dev->flags&IFF_POINTOPOINT)
3215 						continue;
3216 					flag |= IFA_HOST;
3217 				}
3218 
3219 				add_addr(idev, &addr, plen, flag,
3220 					 IFAPROT_UNSPEC);
3221 				addrconf_prefix_route(&addr, plen, 0, idev->dev,
3222 						      0, pflags, GFP_KERNEL);
3223 			}
3224 		}
3225 	}
3226 }
3227 #endif
3228 
3229 static void init_loopback(struct net_device *dev)
3230 {
3231 	struct inet6_dev  *idev;
3232 
3233 	/* ::1 */
3234 
3235 	ASSERT_RTNL();
3236 
3237 	idev = ipv6_find_idev(dev);
3238 	if (IS_ERR(idev)) {
3239 		pr_debug("%s: add_dev failed\n", __func__);
3240 		return;
3241 	}
3242 
3243 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST, IFAPROT_KERNEL_LO);
3244 }
3245 
3246 void addrconf_add_linklocal(struct inet6_dev *idev,
3247 			    const struct in6_addr *addr, u32 flags)
3248 {
3249 	struct ifa6_config cfg = {
3250 		.pfx = addr,
3251 		.plen = 64,
3252 		.ifa_flags = flags | IFA_F_PERMANENT,
3253 		.valid_lft = INFINITY_LIFE_TIME,
3254 		.preferred_lft = INFINITY_LIFE_TIME,
3255 		.scope = IFA_LINK,
3256 		.ifa_proto = IFAPROT_KERNEL_LL
3257 	};
3258 	struct inet6_ifaddr *ifp;
3259 
3260 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3261 	if ((dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad ||
3262 	     idev->cnf.optimistic_dad) &&
3263 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3264 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
3265 #endif
3266 
3267 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3268 	if (!IS_ERR(ifp)) {
3269 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, 0, idev->dev,
3270 				      0, 0, GFP_ATOMIC);
3271 		addrconf_dad_start(ifp);
3272 		in6_ifa_put(ifp);
3273 	}
3274 }
3275 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3276 
3277 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3278 {
3279 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3280 		return true;
3281 
3282 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3283 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3284 		return true;
3285 
3286 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3287 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3288 		return true;
3289 
3290 	return false;
3291 }
3292 
3293 static int ipv6_generate_stable_address(struct in6_addr *address,
3294 					u8 dad_count,
3295 					const struct inet6_dev *idev)
3296 {
3297 	static DEFINE_SPINLOCK(lock);
3298 	static __u32 digest[SHA1_DIGEST_WORDS];
3299 	static __u32 workspace[SHA1_WORKSPACE_WORDS];
3300 
3301 	static union {
3302 		char __data[SHA1_BLOCK_SIZE];
3303 		struct {
3304 			struct in6_addr secret;
3305 			__be32 prefix[2];
3306 			unsigned char hwaddr[MAX_ADDR_LEN];
3307 			u8 dad_count;
3308 		} __packed;
3309 	} data;
3310 
3311 	struct in6_addr secret;
3312 	struct in6_addr temp;
3313 	struct net *net = dev_net(idev->dev);
3314 
3315 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3316 
3317 	if (idev->cnf.stable_secret.initialized)
3318 		secret = idev->cnf.stable_secret.secret;
3319 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3320 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3321 	else
3322 		return -1;
3323 
3324 retry:
3325 	spin_lock_bh(&lock);
3326 
3327 	sha1_init(digest);
3328 	memset(&data, 0, sizeof(data));
3329 	memset(workspace, 0, sizeof(workspace));
3330 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3331 	data.prefix[0] = address->s6_addr32[0];
3332 	data.prefix[1] = address->s6_addr32[1];
3333 	data.secret = secret;
3334 	data.dad_count = dad_count;
3335 
3336 	sha1_transform(digest, data.__data, workspace);
3337 
3338 	temp = *address;
3339 	temp.s6_addr32[2] = (__force __be32)digest[0];
3340 	temp.s6_addr32[3] = (__force __be32)digest[1];
3341 
3342 	spin_unlock_bh(&lock);
3343 
3344 	if (ipv6_reserved_interfaceid(temp)) {
3345 		dad_count++;
3346 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3347 			return -1;
3348 		goto retry;
3349 	}
3350 
3351 	*address = temp;
3352 	return 0;
3353 }
3354 
3355 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3356 {
3357 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3358 
3359 	if (s->initialized)
3360 		return;
3361 	s = &idev->cnf.stable_secret;
3362 	get_random_bytes(&s->secret, sizeof(s->secret));
3363 	s->initialized = true;
3364 }
3365 
3366 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3367 {
3368 	struct in6_addr addr;
3369 
3370 	/* no link local addresses on L3 master devices */
3371 	if (netif_is_l3_master(idev->dev))
3372 		return;
3373 
3374 	/* no link local addresses on devices flagged as slaves */
3375 	if (idev->dev->priv_flags & IFF_NO_ADDRCONF)
3376 		return;
3377 
3378 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3379 
3380 	switch (idev->cnf.addr_gen_mode) {
3381 	case IN6_ADDR_GEN_MODE_RANDOM:
3382 		ipv6_gen_mode_random_init(idev);
3383 		fallthrough;
3384 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3385 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3386 			addrconf_add_linklocal(idev, &addr,
3387 					       IFA_F_STABLE_PRIVACY);
3388 		else if (prefix_route)
3389 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3390 					      0, 0, GFP_KERNEL);
3391 		break;
3392 	case IN6_ADDR_GEN_MODE_EUI64:
3393 		/* addrconf_add_linklocal also adds a prefix_route and we
3394 		 * only need to care about prefix routes if ipv6_generate_eui64
3395 		 * couldn't generate one.
3396 		 */
3397 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3398 			addrconf_add_linklocal(idev, &addr, 0);
3399 		else if (prefix_route)
3400 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3401 					      0, 0, GFP_KERNEL);
3402 		break;
3403 	case IN6_ADDR_GEN_MODE_NONE:
3404 	default:
3405 		/* will not add any link local address */
3406 		break;
3407 	}
3408 }
3409 
3410 static void addrconf_dev_config(struct net_device *dev)
3411 {
3412 	struct inet6_dev *idev;
3413 
3414 	ASSERT_RTNL();
3415 
3416 	if ((dev->type != ARPHRD_ETHER) &&
3417 	    (dev->type != ARPHRD_FDDI) &&
3418 	    (dev->type != ARPHRD_ARCNET) &&
3419 	    (dev->type != ARPHRD_INFINIBAND) &&
3420 	    (dev->type != ARPHRD_IEEE1394) &&
3421 	    (dev->type != ARPHRD_TUNNEL6) &&
3422 	    (dev->type != ARPHRD_6LOWPAN) &&
3423 	    (dev->type != ARPHRD_TUNNEL) &&
3424 	    (dev->type != ARPHRD_NONE) &&
3425 	    (dev->type != ARPHRD_RAWIP)) {
3426 		/* Alas, we support only Ethernet autoconfiguration. */
3427 		idev = __in6_dev_get(dev);
3428 		if (!IS_ERR_OR_NULL(idev) && dev->flags & IFF_UP &&
3429 		    dev->flags & IFF_MULTICAST)
3430 			ipv6_mc_up(idev);
3431 		return;
3432 	}
3433 
3434 	idev = addrconf_add_dev(dev);
3435 	if (IS_ERR(idev))
3436 		return;
3437 
3438 	/* this device type has no EUI support */
3439 	if (dev->type == ARPHRD_NONE &&
3440 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3441 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_RANDOM;
3442 
3443 	addrconf_addr_gen(idev, false);
3444 }
3445 
3446 #if IS_ENABLED(CONFIG_IPV6_SIT)
3447 static void addrconf_sit_config(struct net_device *dev)
3448 {
3449 	struct inet6_dev *idev;
3450 
3451 	ASSERT_RTNL();
3452 
3453 	/*
3454 	 * Configure the tunnel with one of our IPv4
3455 	 * addresses... we should configure all of
3456 	 * our v4 addrs in the tunnel
3457 	 */
3458 
3459 	idev = ipv6_find_idev(dev);
3460 	if (IS_ERR(idev)) {
3461 		pr_debug("%s: add_dev failed\n", __func__);
3462 		return;
3463 	}
3464 
3465 	if (dev->priv_flags & IFF_ISATAP) {
3466 		addrconf_addr_gen(idev, false);
3467 		return;
3468 	}
3469 
3470 	add_v4_addrs(idev);
3471 
3472 	if (dev->flags&IFF_POINTOPOINT)
3473 		addrconf_add_mroute(dev);
3474 }
3475 #endif
3476 
3477 #if IS_ENABLED(CONFIG_NET_IPGRE) || IS_ENABLED(CONFIG_IPV6_GRE)
3478 static void addrconf_gre_config(struct net_device *dev)
3479 {
3480 	struct inet6_dev *idev;
3481 
3482 	ASSERT_RTNL();
3483 
3484 	idev = ipv6_find_idev(dev);
3485 	if (IS_ERR(idev)) {
3486 		pr_debug("%s: add_dev failed\n", __func__);
3487 		return;
3488 	}
3489 
3490 	if (dev->type == ARPHRD_ETHER) {
3491 		addrconf_addr_gen(idev, true);
3492 		return;
3493 	}
3494 
3495 	add_v4_addrs(idev);
3496 
3497 	if (dev->flags & IFF_POINTOPOINT)
3498 		addrconf_add_mroute(dev);
3499 }
3500 #endif
3501 
3502 static void addrconf_init_auto_addrs(struct net_device *dev)
3503 {
3504 	switch (dev->type) {
3505 #if IS_ENABLED(CONFIG_IPV6_SIT)
3506 	case ARPHRD_SIT:
3507 		addrconf_sit_config(dev);
3508 		break;
3509 #endif
3510 #if IS_ENABLED(CONFIG_NET_IPGRE) || IS_ENABLED(CONFIG_IPV6_GRE)
3511 	case ARPHRD_IP6GRE:
3512 	case ARPHRD_IPGRE:
3513 		addrconf_gre_config(dev);
3514 		break;
3515 #endif
3516 	case ARPHRD_LOOPBACK:
3517 		init_loopback(dev);
3518 		break;
3519 
3520 	default:
3521 		addrconf_dev_config(dev);
3522 		break;
3523 	}
3524 }
3525 
3526 static int fixup_permanent_addr(struct net *net,
3527 				struct inet6_dev *idev,
3528 				struct inet6_ifaddr *ifp)
3529 {
3530 	/* !fib6_node means the host route was removed from the
3531 	 * FIB, for example, if 'lo' device is taken down. In that
3532 	 * case regenerate the host route.
3533 	 */
3534 	if (!ifp->rt || !ifp->rt->fib6_node) {
3535 		struct fib6_info *f6i, *prev;
3536 
3537 		f6i = addrconf_f6i_alloc(net, idev, &ifp->addr, false,
3538 					 GFP_ATOMIC, NULL);
3539 		if (IS_ERR(f6i))
3540 			return PTR_ERR(f6i);
3541 
3542 		/* ifp->rt can be accessed outside of rtnl */
3543 		spin_lock(&ifp->lock);
3544 		prev = ifp->rt;
3545 		ifp->rt = f6i;
3546 		spin_unlock(&ifp->lock);
3547 
3548 		fib6_info_release(prev);
3549 	}
3550 
3551 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3552 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3553 				      ifp->rt_priority, idev->dev, 0, 0,
3554 				      GFP_ATOMIC);
3555 	}
3556 
3557 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3558 		addrconf_dad_start(ifp);
3559 
3560 	return 0;
3561 }
3562 
3563 static void addrconf_permanent_addr(struct net *net, struct net_device *dev)
3564 {
3565 	struct inet6_ifaddr *ifp, *tmp;
3566 	struct inet6_dev *idev;
3567 
3568 	idev = __in6_dev_get(dev);
3569 	if (!idev)
3570 		return;
3571 
3572 	write_lock_bh(&idev->lock);
3573 
3574 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3575 		if ((ifp->flags & IFA_F_PERMANENT) &&
3576 		    fixup_permanent_addr(net, idev, ifp) < 0) {
3577 			write_unlock_bh(&idev->lock);
3578 			in6_ifa_hold(ifp);
3579 			ipv6_del_addr(ifp);
3580 			write_lock_bh(&idev->lock);
3581 
3582 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3583 					     idev->dev->name, &ifp->addr);
3584 		}
3585 	}
3586 
3587 	write_unlock_bh(&idev->lock);
3588 }
3589 
3590 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3591 			   void *ptr)
3592 {
3593 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3594 	struct netdev_notifier_change_info *change_info;
3595 	struct netdev_notifier_changeupper_info *info;
3596 	struct inet6_dev *idev = __in6_dev_get(dev);
3597 	struct net *net = dev_net(dev);
3598 	int run_pending = 0;
3599 	int err;
3600 
3601 	switch (event) {
3602 	case NETDEV_REGISTER:
3603 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3604 			idev = ipv6_add_dev(dev);
3605 			if (IS_ERR(idev))
3606 				return notifier_from_errno(PTR_ERR(idev));
3607 		}
3608 		break;
3609 
3610 	case NETDEV_CHANGEMTU:
3611 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3612 		if (dev->mtu < IPV6_MIN_MTU) {
3613 			addrconf_ifdown(dev, dev != net->loopback_dev);
3614 			break;
3615 		}
3616 
3617 		if (idev) {
3618 			rt6_mtu_change(dev, dev->mtu);
3619 			idev->cnf.mtu6 = dev->mtu;
3620 			break;
3621 		}
3622 
3623 		/* allocate new idev */
3624 		idev = ipv6_add_dev(dev);
3625 		if (IS_ERR(idev))
3626 			break;
3627 
3628 		/* device is still not ready */
3629 		if (!(idev->if_flags & IF_READY))
3630 			break;
3631 
3632 		run_pending = 1;
3633 		fallthrough;
3634 	case NETDEV_UP:
3635 	case NETDEV_CHANGE:
3636 		if (idev && idev->cnf.disable_ipv6)
3637 			break;
3638 
3639 		if (dev->priv_flags & IFF_NO_ADDRCONF) {
3640 			if (event == NETDEV_UP && !IS_ERR_OR_NULL(idev) &&
3641 			    dev->flags & IFF_UP && dev->flags & IFF_MULTICAST)
3642 				ipv6_mc_up(idev);
3643 			break;
3644 		}
3645 
3646 		if (event == NETDEV_UP) {
3647 			/* restore routes for permanent addresses */
3648 			addrconf_permanent_addr(net, dev);
3649 
3650 			if (!addrconf_link_ready(dev)) {
3651 				/* device is not ready yet. */
3652 				pr_debug("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3653 					 dev->name);
3654 				break;
3655 			}
3656 
3657 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3658 				idev = ipv6_add_dev(dev);
3659 
3660 			if (!IS_ERR_OR_NULL(idev)) {
3661 				idev->if_flags |= IF_READY;
3662 				run_pending = 1;
3663 			}
3664 		} else if (event == NETDEV_CHANGE) {
3665 			if (!addrconf_link_ready(dev)) {
3666 				/* device is still not ready. */
3667 				rt6_sync_down_dev(dev, event);
3668 				break;
3669 			}
3670 
3671 			if (!IS_ERR_OR_NULL(idev)) {
3672 				if (idev->if_flags & IF_READY) {
3673 					/* device is already configured -
3674 					 * but resend MLD reports, we might
3675 					 * have roamed and need to update
3676 					 * multicast snooping switches
3677 					 */
3678 					ipv6_mc_up(idev);
3679 					change_info = ptr;
3680 					if (change_info->flags_changed & IFF_NOARP)
3681 						addrconf_dad_run(idev, true);
3682 					rt6_sync_up(dev, RTNH_F_LINKDOWN);
3683 					break;
3684 				}
3685 				idev->if_flags |= IF_READY;
3686 			}
3687 
3688 			pr_debug("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3689 				 dev->name);
3690 
3691 			run_pending = 1;
3692 		}
3693 
3694 		addrconf_init_auto_addrs(dev);
3695 
3696 		if (!IS_ERR_OR_NULL(idev)) {
3697 			if (run_pending)
3698 				addrconf_dad_run(idev, false);
3699 
3700 			/* Device has an address by now */
3701 			rt6_sync_up(dev, RTNH_F_DEAD);
3702 
3703 			/*
3704 			 * If the MTU changed during the interface down,
3705 			 * when the interface up, the changed MTU must be
3706 			 * reflected in the idev as well as routers.
3707 			 */
3708 			if (idev->cnf.mtu6 != dev->mtu &&
3709 			    dev->mtu >= IPV6_MIN_MTU) {
3710 				rt6_mtu_change(dev, dev->mtu);
3711 				idev->cnf.mtu6 = dev->mtu;
3712 			}
3713 			idev->tstamp = jiffies;
3714 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3715 
3716 			/*
3717 			 * If the changed mtu during down is lower than
3718 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3719 			 */
3720 			if (dev->mtu < IPV6_MIN_MTU)
3721 				addrconf_ifdown(dev, dev != net->loopback_dev);
3722 		}
3723 		break;
3724 
3725 	case NETDEV_DOWN:
3726 	case NETDEV_UNREGISTER:
3727 		/*
3728 		 *	Remove all addresses from this interface.
3729 		 */
3730 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3731 		break;
3732 
3733 	case NETDEV_CHANGENAME:
3734 		if (idev) {
3735 			snmp6_unregister_dev(idev);
3736 			addrconf_sysctl_unregister(idev);
3737 			err = addrconf_sysctl_register(idev);
3738 			if (err)
3739 				return notifier_from_errno(err);
3740 			err = snmp6_register_dev(idev);
3741 			if (err) {
3742 				addrconf_sysctl_unregister(idev);
3743 				return notifier_from_errno(err);
3744 			}
3745 		}
3746 		break;
3747 
3748 	case NETDEV_PRE_TYPE_CHANGE:
3749 	case NETDEV_POST_TYPE_CHANGE:
3750 		if (idev)
3751 			addrconf_type_change(dev, event);
3752 		break;
3753 
3754 	case NETDEV_CHANGEUPPER:
3755 		info = ptr;
3756 
3757 		/* flush all routes if dev is linked to or unlinked from
3758 		 * an L3 master device (e.g., VRF)
3759 		 */
3760 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3761 			addrconf_ifdown(dev, false);
3762 	}
3763 
3764 	return NOTIFY_OK;
3765 }
3766 
3767 /*
3768  *	addrconf module should be notified of a device going up
3769  */
3770 static struct notifier_block ipv6_dev_notf = {
3771 	.notifier_call = addrconf_notify,
3772 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3773 };
3774 
3775 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3776 {
3777 	struct inet6_dev *idev;
3778 	ASSERT_RTNL();
3779 
3780 	idev = __in6_dev_get(dev);
3781 
3782 	if (event == NETDEV_POST_TYPE_CHANGE)
3783 		ipv6_mc_remap(idev);
3784 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3785 		ipv6_mc_unmap(idev);
3786 }
3787 
3788 static bool addr_is_local(const struct in6_addr *addr)
3789 {
3790 	return ipv6_addr_type(addr) &
3791 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3792 }
3793 
3794 static int addrconf_ifdown(struct net_device *dev, bool unregister)
3795 {
3796 	unsigned long event = unregister ? NETDEV_UNREGISTER : NETDEV_DOWN;
3797 	struct net *net = dev_net(dev);
3798 	struct inet6_dev *idev;
3799 	struct inet6_ifaddr *ifa;
3800 	LIST_HEAD(tmp_addr_list);
3801 	bool keep_addr = false;
3802 	bool was_ready;
3803 	int state, i;
3804 
3805 	ASSERT_RTNL();
3806 
3807 	rt6_disable_ip(dev, event);
3808 
3809 	idev = __in6_dev_get(dev);
3810 	if (!idev)
3811 		return -ENODEV;
3812 
3813 	/*
3814 	 * Step 1: remove reference to ipv6 device from parent device.
3815 	 *	   Do not dev_put!
3816 	 */
3817 	if (unregister) {
3818 		idev->dead = 1;
3819 
3820 		/* protected by rtnl_lock */
3821 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3822 
3823 		/* Step 1.5: remove snmp6 entry */
3824 		snmp6_unregister_dev(idev);
3825 
3826 	}
3827 
3828 	/* combine the user config with event to determine if permanent
3829 	 * addresses are to be removed from address hash table
3830 	 */
3831 	if (!unregister && !idev->cnf.disable_ipv6) {
3832 		/* aggregate the system setting and interface setting */
3833 		int _keep_addr = net->ipv6.devconf_all->keep_addr_on_down;
3834 
3835 		if (!_keep_addr)
3836 			_keep_addr = idev->cnf.keep_addr_on_down;
3837 
3838 		keep_addr = (_keep_addr > 0);
3839 	}
3840 
3841 	/* Step 2: clear hash table */
3842 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3843 		struct hlist_head *h = &net->ipv6.inet6_addr_lst[i];
3844 
3845 		spin_lock_bh(&net->ipv6.addrconf_hash_lock);
3846 restart:
3847 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3848 			if (ifa->idev == idev) {
3849 				addrconf_del_dad_work(ifa);
3850 				/* combined flag + permanent flag decide if
3851 				 * address is retained on a down event
3852 				 */
3853 				if (!keep_addr ||
3854 				    !(ifa->flags & IFA_F_PERMANENT) ||
3855 				    addr_is_local(&ifa->addr)) {
3856 					hlist_del_init_rcu(&ifa->addr_lst);
3857 					goto restart;
3858 				}
3859 			}
3860 		}
3861 		spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
3862 	}
3863 
3864 	write_lock_bh(&idev->lock);
3865 
3866 	addrconf_del_rs_timer(idev);
3867 
3868 	/* Step 2: clear flags for stateless addrconf, repeated down
3869 	 *         detection
3870 	 */
3871 	was_ready = idev->if_flags & IF_READY;
3872 	if (!unregister)
3873 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3874 
3875 	/* Step 3: clear tempaddr list */
3876 	while (!list_empty(&idev->tempaddr_list)) {
3877 		ifa = list_first_entry(&idev->tempaddr_list,
3878 				       struct inet6_ifaddr, tmp_list);
3879 		list_del(&ifa->tmp_list);
3880 		write_unlock_bh(&idev->lock);
3881 		spin_lock_bh(&ifa->lock);
3882 
3883 		if (ifa->ifpub) {
3884 			in6_ifa_put(ifa->ifpub);
3885 			ifa->ifpub = NULL;
3886 		}
3887 		spin_unlock_bh(&ifa->lock);
3888 		in6_ifa_put(ifa);
3889 		write_lock_bh(&idev->lock);
3890 	}
3891 
3892 	list_for_each_entry(ifa, &idev->addr_list, if_list)
3893 		list_add_tail(&ifa->if_list_aux, &tmp_addr_list);
3894 	write_unlock_bh(&idev->lock);
3895 
3896 	while (!list_empty(&tmp_addr_list)) {
3897 		struct fib6_info *rt = NULL;
3898 		bool keep;
3899 
3900 		ifa = list_first_entry(&tmp_addr_list,
3901 				       struct inet6_ifaddr, if_list_aux);
3902 		list_del(&ifa->if_list_aux);
3903 
3904 		addrconf_del_dad_work(ifa);
3905 
3906 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3907 			!addr_is_local(&ifa->addr);
3908 
3909 		spin_lock_bh(&ifa->lock);
3910 
3911 		if (keep) {
3912 			/* set state to skip the notifier below */
3913 			state = INET6_IFADDR_STATE_DEAD;
3914 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3915 			if (!(ifa->flags & IFA_F_NODAD))
3916 				ifa->flags |= IFA_F_TENTATIVE;
3917 
3918 			rt = ifa->rt;
3919 			ifa->rt = NULL;
3920 		} else {
3921 			state = ifa->state;
3922 			ifa->state = INET6_IFADDR_STATE_DEAD;
3923 		}
3924 
3925 		spin_unlock_bh(&ifa->lock);
3926 
3927 		if (rt)
3928 			ip6_del_rt(net, rt, false);
3929 
3930 		if (state != INET6_IFADDR_STATE_DEAD) {
3931 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3932 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3933 		} else {
3934 			if (idev->cnf.forwarding)
3935 				addrconf_leave_anycast(ifa);
3936 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3937 		}
3938 
3939 		if (!keep) {
3940 			write_lock_bh(&idev->lock);
3941 			list_del_rcu(&ifa->if_list);
3942 			write_unlock_bh(&idev->lock);
3943 			in6_ifa_put(ifa);
3944 		}
3945 	}
3946 
3947 	/* Step 5: Discard anycast and multicast list */
3948 	if (unregister) {
3949 		ipv6_ac_destroy_dev(idev);
3950 		ipv6_mc_destroy_dev(idev);
3951 	} else if (was_ready) {
3952 		ipv6_mc_down(idev);
3953 	}
3954 
3955 	idev->tstamp = jiffies;
3956 	idev->ra_mtu = 0;
3957 
3958 	/* Last: Shot the device (if unregistered) */
3959 	if (unregister) {
3960 		addrconf_sysctl_unregister(idev);
3961 		neigh_parms_release(&nd_tbl, idev->nd_parms);
3962 		neigh_ifdown(&nd_tbl, dev);
3963 		in6_dev_put(idev);
3964 	}
3965 	return 0;
3966 }
3967 
3968 static void addrconf_rs_timer(struct timer_list *t)
3969 {
3970 	struct inet6_dev *idev = from_timer(idev, t, rs_timer);
3971 	struct net_device *dev = idev->dev;
3972 	struct in6_addr lladdr;
3973 
3974 	write_lock(&idev->lock);
3975 	if (idev->dead || !(idev->if_flags & IF_READY))
3976 		goto out;
3977 
3978 	if (!ipv6_accept_ra(idev))
3979 		goto out;
3980 
3981 	/* Announcement received after solicitation was sent */
3982 	if (idev->if_flags & IF_RA_RCVD)
3983 		goto out;
3984 
3985 	if (idev->rs_probes++ < idev->cnf.rtr_solicits || idev->cnf.rtr_solicits < 0) {
3986 		write_unlock(&idev->lock);
3987 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
3988 			ndisc_send_rs(dev, &lladdr,
3989 				      &in6addr_linklocal_allrouters);
3990 		else
3991 			goto put;
3992 
3993 		write_lock(&idev->lock);
3994 		idev->rs_interval = rfc3315_s14_backoff_update(
3995 			idev->rs_interval, idev->cnf.rtr_solicit_max_interval);
3996 		/* The wait after the last probe can be shorter */
3997 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
3998 					     idev->cnf.rtr_solicits) ?
3999 				      idev->cnf.rtr_solicit_delay :
4000 				      idev->rs_interval);
4001 	} else {
4002 		/*
4003 		 * Note: we do not support deprecated "all on-link"
4004 		 * assumption any longer.
4005 		 */
4006 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
4007 	}
4008 
4009 out:
4010 	write_unlock(&idev->lock);
4011 put:
4012 	in6_dev_put(idev);
4013 }
4014 
4015 /*
4016  *	Duplicate Address Detection
4017  */
4018 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
4019 {
4020 	unsigned long rand_num;
4021 	struct inet6_dev *idev = ifp->idev;
4022 	u64 nonce;
4023 
4024 	if (ifp->flags & IFA_F_OPTIMISTIC)
4025 		rand_num = 0;
4026 	else
4027 		rand_num = get_random_u32_below(idev->cnf.rtr_solicit_delay ? : 1);
4028 
4029 	nonce = 0;
4030 	if (idev->cnf.enhanced_dad ||
4031 	    dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad) {
4032 		do
4033 			get_random_bytes(&nonce, 6);
4034 		while (nonce == 0);
4035 	}
4036 	ifp->dad_nonce = nonce;
4037 	ifp->dad_probes = idev->cnf.dad_transmits;
4038 	addrconf_mod_dad_work(ifp, rand_num);
4039 }
4040 
4041 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
4042 {
4043 	struct inet6_dev *idev = ifp->idev;
4044 	struct net_device *dev = idev->dev;
4045 	bool bump_id, notify = false;
4046 	struct net *net;
4047 
4048 	addrconf_join_solict(dev, &ifp->addr);
4049 
4050 	read_lock_bh(&idev->lock);
4051 	spin_lock(&ifp->lock);
4052 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
4053 		goto out;
4054 
4055 	net = dev_net(dev);
4056 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
4057 	    (net->ipv6.devconf_all->accept_dad < 1 &&
4058 	     idev->cnf.accept_dad < 1) ||
4059 	    !(ifp->flags&IFA_F_TENTATIVE) ||
4060 	    ifp->flags & IFA_F_NODAD) {
4061 		bool send_na = false;
4062 
4063 		if (ifp->flags & IFA_F_TENTATIVE &&
4064 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4065 			send_na = true;
4066 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4067 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4068 		spin_unlock(&ifp->lock);
4069 		read_unlock_bh(&idev->lock);
4070 
4071 		addrconf_dad_completed(ifp, bump_id, send_na);
4072 		return;
4073 	}
4074 
4075 	if (!(idev->if_flags & IF_READY)) {
4076 		spin_unlock(&ifp->lock);
4077 		read_unlock_bh(&idev->lock);
4078 		/*
4079 		 * If the device is not ready:
4080 		 * - keep it tentative if it is a permanent address.
4081 		 * - otherwise, kill it.
4082 		 */
4083 		in6_ifa_hold(ifp);
4084 		addrconf_dad_stop(ifp, 0);
4085 		return;
4086 	}
4087 
4088 	/*
4089 	 * Optimistic nodes can start receiving
4090 	 * Frames right away
4091 	 */
4092 	if (ifp->flags & IFA_F_OPTIMISTIC) {
4093 		ip6_ins_rt(net, ifp->rt);
4094 		if (ipv6_use_optimistic_addr(net, idev)) {
4095 			/* Because optimistic nodes can use this address,
4096 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
4097 			 */
4098 			notify = true;
4099 		}
4100 	}
4101 
4102 	addrconf_dad_kick(ifp);
4103 out:
4104 	spin_unlock(&ifp->lock);
4105 	read_unlock_bh(&idev->lock);
4106 	if (notify)
4107 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
4108 }
4109 
4110 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
4111 {
4112 	bool begin_dad = false;
4113 
4114 	spin_lock_bh(&ifp->lock);
4115 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
4116 		ifp->state = INET6_IFADDR_STATE_PREDAD;
4117 		begin_dad = true;
4118 	}
4119 	spin_unlock_bh(&ifp->lock);
4120 
4121 	if (begin_dad)
4122 		addrconf_mod_dad_work(ifp, 0);
4123 }
4124 
4125 static void addrconf_dad_work(struct work_struct *w)
4126 {
4127 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
4128 						struct inet6_ifaddr,
4129 						dad_work);
4130 	struct inet6_dev *idev = ifp->idev;
4131 	bool bump_id, disable_ipv6 = false;
4132 	struct in6_addr mcaddr;
4133 
4134 	enum {
4135 		DAD_PROCESS,
4136 		DAD_BEGIN,
4137 		DAD_ABORT,
4138 	} action = DAD_PROCESS;
4139 
4140 	rtnl_lock();
4141 
4142 	spin_lock_bh(&ifp->lock);
4143 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
4144 		action = DAD_BEGIN;
4145 		ifp->state = INET6_IFADDR_STATE_DAD;
4146 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
4147 		action = DAD_ABORT;
4148 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
4149 
4150 		if ((dev_net(idev->dev)->ipv6.devconf_all->accept_dad > 1 ||
4151 		     idev->cnf.accept_dad > 1) &&
4152 		    !idev->cnf.disable_ipv6 &&
4153 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
4154 			struct in6_addr addr;
4155 
4156 			addr.s6_addr32[0] = htonl(0xfe800000);
4157 			addr.s6_addr32[1] = 0;
4158 
4159 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
4160 			    ipv6_addr_equal(&ifp->addr, &addr)) {
4161 				/* DAD failed for link-local based on MAC */
4162 				idev->cnf.disable_ipv6 = 1;
4163 
4164 				pr_info("%s: IPv6 being disabled!\n",
4165 					ifp->idev->dev->name);
4166 				disable_ipv6 = true;
4167 			}
4168 		}
4169 	}
4170 	spin_unlock_bh(&ifp->lock);
4171 
4172 	if (action == DAD_BEGIN) {
4173 		addrconf_dad_begin(ifp);
4174 		goto out;
4175 	} else if (action == DAD_ABORT) {
4176 		in6_ifa_hold(ifp);
4177 		addrconf_dad_stop(ifp, 1);
4178 		if (disable_ipv6)
4179 			addrconf_ifdown(idev->dev, false);
4180 		goto out;
4181 	}
4182 
4183 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
4184 		goto out;
4185 
4186 	write_lock_bh(&idev->lock);
4187 	if (idev->dead || !(idev->if_flags & IF_READY)) {
4188 		write_unlock_bh(&idev->lock);
4189 		goto out;
4190 	}
4191 
4192 	spin_lock(&ifp->lock);
4193 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
4194 		spin_unlock(&ifp->lock);
4195 		write_unlock_bh(&idev->lock);
4196 		goto out;
4197 	}
4198 
4199 	if (ifp->dad_probes == 0) {
4200 		bool send_na = false;
4201 
4202 		/*
4203 		 * DAD was successful
4204 		 */
4205 
4206 		if (ifp->flags & IFA_F_TENTATIVE &&
4207 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4208 			send_na = true;
4209 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4210 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4211 		spin_unlock(&ifp->lock);
4212 		write_unlock_bh(&idev->lock);
4213 
4214 		addrconf_dad_completed(ifp, bump_id, send_na);
4215 
4216 		goto out;
4217 	}
4218 
4219 	ifp->dad_probes--;
4220 	addrconf_mod_dad_work(ifp,
4221 			      max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME),
4222 				  HZ/100));
4223 	spin_unlock(&ifp->lock);
4224 	write_unlock_bh(&idev->lock);
4225 
4226 	/* send a neighbour solicitation for our addr */
4227 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4228 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4229 		      ifp->dad_nonce);
4230 out:
4231 	in6_ifa_put(ifp);
4232 	rtnl_unlock();
4233 }
4234 
4235 /* ifp->idev must be at least read locked */
4236 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4237 {
4238 	struct inet6_ifaddr *ifpiter;
4239 	struct inet6_dev *idev = ifp->idev;
4240 
4241 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4242 		if (ifpiter->scope > IFA_LINK)
4243 			break;
4244 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4245 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4246 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4247 		    IFA_F_PERMANENT)
4248 			return false;
4249 	}
4250 	return true;
4251 }
4252 
4253 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
4254 				   bool send_na)
4255 {
4256 	struct net_device *dev = ifp->idev->dev;
4257 	struct in6_addr lladdr;
4258 	bool send_rs, send_mld;
4259 
4260 	addrconf_del_dad_work(ifp);
4261 
4262 	/*
4263 	 *	Configure the address for reception. Now it is valid.
4264 	 */
4265 
4266 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4267 
4268 	/* If added prefix is link local and we are prepared to process
4269 	   router advertisements, start sending router solicitations.
4270 	 */
4271 
4272 	read_lock_bh(&ifp->idev->lock);
4273 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4274 	send_rs = send_mld &&
4275 		  ipv6_accept_ra(ifp->idev) &&
4276 		  ifp->idev->cnf.rtr_solicits != 0 &&
4277 		  (dev->flags & IFF_LOOPBACK) == 0 &&
4278 		  (dev->type != ARPHRD_TUNNEL) &&
4279 		  !netif_is_team_port(dev);
4280 	read_unlock_bh(&ifp->idev->lock);
4281 
4282 	/* While dad is in progress mld report's source address is in6_addrany.
4283 	 * Resend with proper ll now.
4284 	 */
4285 	if (send_mld)
4286 		ipv6_mc_dad_complete(ifp->idev);
4287 
4288 	/* send unsolicited NA if enabled */
4289 	if (send_na &&
4290 	    (ifp->idev->cnf.ndisc_notify ||
4291 	     dev_net(dev)->ipv6.devconf_all->ndisc_notify)) {
4292 		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifp->addr,
4293 			      /*router=*/ !!ifp->idev->cnf.forwarding,
4294 			      /*solicited=*/ false, /*override=*/ true,
4295 			      /*inc_opt=*/ true);
4296 	}
4297 
4298 	if (send_rs) {
4299 		/*
4300 		 *	If a host as already performed a random delay
4301 		 *	[...] as part of DAD [...] there is no need
4302 		 *	to delay again before sending the first RS
4303 		 */
4304 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4305 			return;
4306 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4307 
4308 		write_lock_bh(&ifp->idev->lock);
4309 		spin_lock(&ifp->lock);
4310 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4311 			ifp->idev->cnf.rtr_solicit_interval);
4312 		ifp->idev->rs_probes = 1;
4313 		ifp->idev->if_flags |= IF_RS_SENT;
4314 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4315 		spin_unlock(&ifp->lock);
4316 		write_unlock_bh(&ifp->idev->lock);
4317 	}
4318 
4319 	if (bump_id)
4320 		rt_genid_bump_ipv6(dev_net(dev));
4321 
4322 	/* Make sure that a new temporary address will be created
4323 	 * before this temporary address becomes deprecated.
4324 	 */
4325 	if (ifp->flags & IFA_F_TEMPORARY)
4326 		addrconf_verify_rtnl(dev_net(dev));
4327 }
4328 
4329 static void addrconf_dad_run(struct inet6_dev *idev, bool restart)
4330 {
4331 	struct inet6_ifaddr *ifp;
4332 
4333 	read_lock_bh(&idev->lock);
4334 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4335 		spin_lock(&ifp->lock);
4336 		if ((ifp->flags & IFA_F_TENTATIVE &&
4337 		     ifp->state == INET6_IFADDR_STATE_DAD) || restart) {
4338 			if (restart)
4339 				ifp->state = INET6_IFADDR_STATE_PREDAD;
4340 			addrconf_dad_kick(ifp);
4341 		}
4342 		spin_unlock(&ifp->lock);
4343 	}
4344 	read_unlock_bh(&idev->lock);
4345 }
4346 
4347 #ifdef CONFIG_PROC_FS
4348 struct if6_iter_state {
4349 	struct seq_net_private p;
4350 	int bucket;
4351 	int offset;
4352 };
4353 
4354 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4355 {
4356 	struct if6_iter_state *state = seq->private;
4357 	struct net *net = seq_file_net(seq);
4358 	struct inet6_ifaddr *ifa = NULL;
4359 	int p = 0;
4360 
4361 	/* initial bucket if pos is 0 */
4362 	if (pos == 0) {
4363 		state->bucket = 0;
4364 		state->offset = 0;
4365 	}
4366 
4367 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4368 		hlist_for_each_entry_rcu(ifa, &net->ipv6.inet6_addr_lst[state->bucket],
4369 					 addr_lst) {
4370 			/* sync with offset */
4371 			if (p < state->offset) {
4372 				p++;
4373 				continue;
4374 			}
4375 			return ifa;
4376 		}
4377 
4378 		/* prepare for next bucket */
4379 		state->offset = 0;
4380 		p = 0;
4381 	}
4382 	return NULL;
4383 }
4384 
4385 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4386 					 struct inet6_ifaddr *ifa)
4387 {
4388 	struct if6_iter_state *state = seq->private;
4389 	struct net *net = seq_file_net(seq);
4390 
4391 	hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4392 		state->offset++;
4393 		return ifa;
4394 	}
4395 
4396 	state->offset = 0;
4397 	while (++state->bucket < IN6_ADDR_HSIZE) {
4398 		hlist_for_each_entry_rcu(ifa,
4399 				     &net->ipv6.inet6_addr_lst[state->bucket], addr_lst) {
4400 			return ifa;
4401 		}
4402 	}
4403 
4404 	return NULL;
4405 }
4406 
4407 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4408 	__acquires(rcu)
4409 {
4410 	rcu_read_lock();
4411 	return if6_get_first(seq, *pos);
4412 }
4413 
4414 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4415 {
4416 	struct inet6_ifaddr *ifa;
4417 
4418 	ifa = if6_get_next(seq, v);
4419 	++*pos;
4420 	return ifa;
4421 }
4422 
4423 static void if6_seq_stop(struct seq_file *seq, void *v)
4424 	__releases(rcu)
4425 {
4426 	rcu_read_unlock();
4427 }
4428 
4429 static int if6_seq_show(struct seq_file *seq, void *v)
4430 {
4431 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4432 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4433 		   &ifp->addr,
4434 		   ifp->idev->dev->ifindex,
4435 		   ifp->prefix_len,
4436 		   ifp->scope,
4437 		   (u8) ifp->flags,
4438 		   ifp->idev->dev->name);
4439 	return 0;
4440 }
4441 
4442 static const struct seq_operations if6_seq_ops = {
4443 	.start	= if6_seq_start,
4444 	.next	= if6_seq_next,
4445 	.show	= if6_seq_show,
4446 	.stop	= if6_seq_stop,
4447 };
4448 
4449 static int __net_init if6_proc_net_init(struct net *net)
4450 {
4451 	if (!proc_create_net("if_inet6", 0444, net->proc_net, &if6_seq_ops,
4452 			sizeof(struct if6_iter_state)))
4453 		return -ENOMEM;
4454 	return 0;
4455 }
4456 
4457 static void __net_exit if6_proc_net_exit(struct net *net)
4458 {
4459 	remove_proc_entry("if_inet6", net->proc_net);
4460 }
4461 
4462 static struct pernet_operations if6_proc_net_ops = {
4463 	.init = if6_proc_net_init,
4464 	.exit = if6_proc_net_exit,
4465 };
4466 
4467 int __init if6_proc_init(void)
4468 {
4469 	return register_pernet_subsys(&if6_proc_net_ops);
4470 }
4471 
4472 void if6_proc_exit(void)
4473 {
4474 	unregister_pernet_subsys(&if6_proc_net_ops);
4475 }
4476 #endif	/* CONFIG_PROC_FS */
4477 
4478 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4479 /* Check if address is a home address configured on any interface. */
4480 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4481 {
4482 	unsigned int hash = inet6_addr_hash(net, addr);
4483 	struct inet6_ifaddr *ifp = NULL;
4484 	int ret = 0;
4485 
4486 	rcu_read_lock();
4487 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
4488 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4489 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4490 			ret = 1;
4491 			break;
4492 		}
4493 	}
4494 	rcu_read_unlock();
4495 	return ret;
4496 }
4497 #endif
4498 
4499 /* RFC6554 has some algorithm to avoid loops in segment routing by
4500  * checking if the segments contains any of a local interface address.
4501  *
4502  * Quote:
4503  *
4504  * To detect loops in the SRH, a router MUST determine if the SRH
4505  * includes multiple addresses assigned to any interface on that router.
4506  * If such addresses appear more than once and are separated by at least
4507  * one address not assigned to that router.
4508  */
4509 int ipv6_chk_rpl_srh_loop(struct net *net, const struct in6_addr *segs,
4510 			  unsigned char nsegs)
4511 {
4512 	const struct in6_addr *addr;
4513 	int i, ret = 0, found = 0;
4514 	struct inet6_ifaddr *ifp;
4515 	bool separated = false;
4516 	unsigned int hash;
4517 	bool hash_found;
4518 
4519 	rcu_read_lock();
4520 	for (i = 0; i < nsegs; i++) {
4521 		addr = &segs[i];
4522 		hash = inet6_addr_hash(net, addr);
4523 
4524 		hash_found = false;
4525 		hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
4526 
4527 			if (ipv6_addr_equal(&ifp->addr, addr)) {
4528 				hash_found = true;
4529 				break;
4530 			}
4531 		}
4532 
4533 		if (hash_found) {
4534 			if (found > 1 && separated) {
4535 				ret = 1;
4536 				break;
4537 			}
4538 
4539 			separated = false;
4540 			found++;
4541 		} else {
4542 			separated = true;
4543 		}
4544 	}
4545 	rcu_read_unlock();
4546 
4547 	return ret;
4548 }
4549 
4550 /*
4551  *	Periodic address status verification
4552  */
4553 
4554 static void addrconf_verify_rtnl(struct net *net)
4555 {
4556 	unsigned long now, next, next_sec, next_sched;
4557 	struct inet6_ifaddr *ifp;
4558 	int i;
4559 
4560 	ASSERT_RTNL();
4561 
4562 	rcu_read_lock_bh();
4563 	now = jiffies;
4564 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4565 
4566 	cancel_delayed_work(&net->ipv6.addr_chk_work);
4567 
4568 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4569 restart:
4570 		hlist_for_each_entry_rcu_bh(ifp, &net->ipv6.inet6_addr_lst[i], addr_lst) {
4571 			unsigned long age;
4572 
4573 			/* When setting preferred_lft to a value not zero or
4574 			 * infinity, while valid_lft is infinity
4575 			 * IFA_F_PERMANENT has a non-infinity life time.
4576 			 */
4577 			if ((ifp->flags & IFA_F_PERMANENT) &&
4578 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4579 				continue;
4580 
4581 			spin_lock(&ifp->lock);
4582 			/* We try to batch several events at once. */
4583 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4584 
4585 			if ((ifp->flags&IFA_F_TEMPORARY) &&
4586 			    !(ifp->flags&IFA_F_TENTATIVE) &&
4587 			    ifp->prefered_lft != INFINITY_LIFE_TIME &&
4588 			    !ifp->regen_count && ifp->ifpub) {
4589 				/* This is a non-regenerated temporary addr. */
4590 
4591 				unsigned long regen_advance = ifp->idev->cnf.regen_max_retry *
4592 					ifp->idev->cnf.dad_transmits *
4593 					max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
4594 
4595 				if (age + regen_advance >= ifp->prefered_lft) {
4596 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4597 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4598 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4599 
4600 					ifp->regen_count++;
4601 					in6_ifa_hold(ifp);
4602 					in6_ifa_hold(ifpub);
4603 					spin_unlock(&ifp->lock);
4604 
4605 					spin_lock(&ifpub->lock);
4606 					ifpub->regen_count = 0;
4607 					spin_unlock(&ifpub->lock);
4608 					rcu_read_unlock_bh();
4609 					ipv6_create_tempaddr(ifpub, true);
4610 					in6_ifa_put(ifpub);
4611 					in6_ifa_put(ifp);
4612 					rcu_read_lock_bh();
4613 					goto restart;
4614 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4615 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4616 			}
4617 
4618 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4619 			    age >= ifp->valid_lft) {
4620 				spin_unlock(&ifp->lock);
4621 				in6_ifa_hold(ifp);
4622 				rcu_read_unlock_bh();
4623 				ipv6_del_addr(ifp);
4624 				rcu_read_lock_bh();
4625 				goto restart;
4626 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4627 				spin_unlock(&ifp->lock);
4628 				continue;
4629 			} else if (age >= ifp->prefered_lft) {
4630 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4631 				int deprecate = 0;
4632 
4633 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4634 					deprecate = 1;
4635 					ifp->flags |= IFA_F_DEPRECATED;
4636 				}
4637 
4638 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4639 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4640 					next = ifp->tstamp + ifp->valid_lft * HZ;
4641 
4642 				spin_unlock(&ifp->lock);
4643 
4644 				if (deprecate) {
4645 					in6_ifa_hold(ifp);
4646 
4647 					ipv6_ifa_notify(0, ifp);
4648 					in6_ifa_put(ifp);
4649 					goto restart;
4650 				}
4651 			} else {
4652 				/* ifp->prefered_lft <= ifp->valid_lft */
4653 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4654 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4655 				spin_unlock(&ifp->lock);
4656 			}
4657 		}
4658 	}
4659 
4660 	next_sec = round_jiffies_up(next);
4661 	next_sched = next;
4662 
4663 	/* If rounded timeout is accurate enough, accept it. */
4664 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4665 		next_sched = next_sec;
4666 
4667 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4668 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4669 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4670 
4671 	pr_debug("now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4672 		 now, next, next_sec, next_sched);
4673 	mod_delayed_work(addrconf_wq, &net->ipv6.addr_chk_work, next_sched - now);
4674 	rcu_read_unlock_bh();
4675 }
4676 
4677 static void addrconf_verify_work(struct work_struct *w)
4678 {
4679 	struct net *net = container_of(to_delayed_work(w), struct net,
4680 				       ipv6.addr_chk_work);
4681 
4682 	rtnl_lock();
4683 	addrconf_verify_rtnl(net);
4684 	rtnl_unlock();
4685 }
4686 
4687 static void addrconf_verify(struct net *net)
4688 {
4689 	mod_delayed_work(addrconf_wq, &net->ipv6.addr_chk_work, 0);
4690 }
4691 
4692 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4693 				     struct in6_addr **peer_pfx)
4694 {
4695 	struct in6_addr *pfx = NULL;
4696 
4697 	*peer_pfx = NULL;
4698 
4699 	if (addr)
4700 		pfx = nla_data(addr);
4701 
4702 	if (local) {
4703 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4704 			*peer_pfx = pfx;
4705 		pfx = nla_data(local);
4706 	}
4707 
4708 	return pfx;
4709 }
4710 
4711 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4712 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4713 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4714 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4715 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4716 	[IFA_RT_PRIORITY]	= { .len = sizeof(u32) },
4717 	[IFA_TARGET_NETNSID]	= { .type = NLA_S32 },
4718 	[IFA_PROTO]		= { .type = NLA_U8 },
4719 };
4720 
4721 static int
4722 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4723 		  struct netlink_ext_ack *extack)
4724 {
4725 	struct net *net = sock_net(skb->sk);
4726 	struct ifaddrmsg *ifm;
4727 	struct nlattr *tb[IFA_MAX+1];
4728 	struct in6_addr *pfx, *peer_pfx;
4729 	u32 ifa_flags;
4730 	int err;
4731 
4732 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4733 				     ifa_ipv6_policy, extack);
4734 	if (err < 0)
4735 		return err;
4736 
4737 	ifm = nlmsg_data(nlh);
4738 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4739 	if (!pfx)
4740 		return -EINVAL;
4741 
4742 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4743 
4744 	/* We ignore other flags so far. */
4745 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4746 
4747 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4748 			      ifm->ifa_prefixlen, extack);
4749 }
4750 
4751 static int modify_prefix_route(struct inet6_ifaddr *ifp,
4752 			       unsigned long expires, u32 flags,
4753 			       bool modify_peer)
4754 {
4755 	struct fib6_info *f6i;
4756 	u32 prio;
4757 
4758 	f6i = addrconf_get_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4759 					ifp->prefix_len,
4760 					ifp->idev->dev, 0, RTF_DEFAULT, true);
4761 	if (!f6i)
4762 		return -ENOENT;
4763 
4764 	prio = ifp->rt_priority ? : IP6_RT_PRIO_ADDRCONF;
4765 	if (f6i->fib6_metric != prio) {
4766 		/* delete old one */
4767 		ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
4768 
4769 		/* add new one */
4770 		addrconf_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4771 				      ifp->prefix_len,
4772 				      ifp->rt_priority, ifp->idev->dev,
4773 				      expires, flags, GFP_KERNEL);
4774 	} else {
4775 		if (!expires)
4776 			fib6_clean_expires(f6i);
4777 		else
4778 			fib6_set_expires(f6i, expires);
4779 
4780 		fib6_info_release(f6i);
4781 	}
4782 
4783 	return 0;
4784 }
4785 
4786 static int inet6_addr_modify(struct net *net, struct inet6_ifaddr *ifp,
4787 			     struct ifa6_config *cfg)
4788 {
4789 	u32 flags;
4790 	clock_t expires;
4791 	unsigned long timeout;
4792 	bool was_managetempaddr;
4793 	bool had_prefixroute;
4794 	bool new_peer = false;
4795 
4796 	ASSERT_RTNL();
4797 
4798 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
4799 		return -EINVAL;
4800 
4801 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR &&
4802 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4803 		return -EINVAL;
4804 
4805 	if (!(ifp->flags & IFA_F_TENTATIVE) || ifp->flags & IFA_F_DADFAILED)
4806 		cfg->ifa_flags &= ~IFA_F_OPTIMISTIC;
4807 
4808 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
4809 	if (addrconf_finite_timeout(timeout)) {
4810 		expires = jiffies_to_clock_t(timeout * HZ);
4811 		cfg->valid_lft = timeout;
4812 		flags = RTF_EXPIRES;
4813 	} else {
4814 		expires = 0;
4815 		flags = 0;
4816 		cfg->ifa_flags |= IFA_F_PERMANENT;
4817 	}
4818 
4819 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
4820 	if (addrconf_finite_timeout(timeout)) {
4821 		if (timeout == 0)
4822 			cfg->ifa_flags |= IFA_F_DEPRECATED;
4823 		cfg->preferred_lft = timeout;
4824 	}
4825 
4826 	if (cfg->peer_pfx &&
4827 	    memcmp(&ifp->peer_addr, cfg->peer_pfx, sizeof(struct in6_addr))) {
4828 		if (!ipv6_addr_any(&ifp->peer_addr))
4829 			cleanup_prefix_route(ifp, expires, true, true);
4830 		new_peer = true;
4831 	}
4832 
4833 	spin_lock_bh(&ifp->lock);
4834 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4835 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4836 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4837 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4838 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4839 			IFA_F_NOPREFIXROUTE);
4840 	ifp->flags |= cfg->ifa_flags;
4841 	ifp->tstamp = jiffies;
4842 	ifp->valid_lft = cfg->valid_lft;
4843 	ifp->prefered_lft = cfg->preferred_lft;
4844 	ifp->ifa_proto = cfg->ifa_proto;
4845 
4846 	if (cfg->rt_priority && cfg->rt_priority != ifp->rt_priority)
4847 		ifp->rt_priority = cfg->rt_priority;
4848 
4849 	if (new_peer)
4850 		ifp->peer_addr = *cfg->peer_pfx;
4851 
4852 	spin_unlock_bh(&ifp->lock);
4853 	if (!(ifp->flags&IFA_F_TENTATIVE))
4854 		ipv6_ifa_notify(0, ifp);
4855 
4856 	if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
4857 		int rc = -ENOENT;
4858 
4859 		if (had_prefixroute)
4860 			rc = modify_prefix_route(ifp, expires, flags, false);
4861 
4862 		/* prefix route could have been deleted; if so restore it */
4863 		if (rc == -ENOENT) {
4864 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4865 					      ifp->rt_priority, ifp->idev->dev,
4866 					      expires, flags, GFP_KERNEL);
4867 		}
4868 
4869 		if (had_prefixroute && !ipv6_addr_any(&ifp->peer_addr))
4870 			rc = modify_prefix_route(ifp, expires, flags, true);
4871 
4872 		if (rc == -ENOENT && !ipv6_addr_any(&ifp->peer_addr)) {
4873 			addrconf_prefix_route(&ifp->peer_addr, ifp->prefix_len,
4874 					      ifp->rt_priority, ifp->idev->dev,
4875 					      expires, flags, GFP_KERNEL);
4876 		}
4877 	} else if (had_prefixroute) {
4878 		enum cleanup_prefix_rt_t action;
4879 		unsigned long rt_expires;
4880 
4881 		write_lock_bh(&ifp->idev->lock);
4882 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4883 		write_unlock_bh(&ifp->idev->lock);
4884 
4885 		if (action != CLEANUP_PREFIX_RT_NOP) {
4886 			cleanup_prefix_route(ifp, rt_expires,
4887 				action == CLEANUP_PREFIX_RT_DEL, false);
4888 		}
4889 	}
4890 
4891 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4892 		if (was_managetempaddr &&
4893 		    !(ifp->flags & IFA_F_MANAGETEMPADDR)) {
4894 			cfg->valid_lft = 0;
4895 			cfg->preferred_lft = 0;
4896 		}
4897 		manage_tempaddrs(ifp->idev, ifp, cfg->valid_lft,
4898 				 cfg->preferred_lft, !was_managetempaddr,
4899 				 jiffies);
4900 	}
4901 
4902 	addrconf_verify_rtnl(net);
4903 
4904 	return 0;
4905 }
4906 
4907 static int
4908 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4909 		  struct netlink_ext_ack *extack)
4910 {
4911 	struct net *net = sock_net(skb->sk);
4912 	struct ifaddrmsg *ifm;
4913 	struct nlattr *tb[IFA_MAX+1];
4914 	struct in6_addr *peer_pfx;
4915 	struct inet6_ifaddr *ifa;
4916 	struct net_device *dev;
4917 	struct inet6_dev *idev;
4918 	struct ifa6_config cfg;
4919 	int err;
4920 
4921 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4922 				     ifa_ipv6_policy, extack);
4923 	if (err < 0)
4924 		return err;
4925 
4926 	memset(&cfg, 0, sizeof(cfg));
4927 
4928 	ifm = nlmsg_data(nlh);
4929 	cfg.pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4930 	if (!cfg.pfx)
4931 		return -EINVAL;
4932 
4933 	cfg.peer_pfx = peer_pfx;
4934 	cfg.plen = ifm->ifa_prefixlen;
4935 	if (tb[IFA_RT_PRIORITY])
4936 		cfg.rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
4937 
4938 	if (tb[IFA_PROTO])
4939 		cfg.ifa_proto = nla_get_u8(tb[IFA_PROTO]);
4940 
4941 	cfg.valid_lft = INFINITY_LIFE_TIME;
4942 	cfg.preferred_lft = INFINITY_LIFE_TIME;
4943 
4944 	if (tb[IFA_CACHEINFO]) {
4945 		struct ifa_cacheinfo *ci;
4946 
4947 		ci = nla_data(tb[IFA_CACHEINFO]);
4948 		cfg.valid_lft = ci->ifa_valid;
4949 		cfg.preferred_lft = ci->ifa_prefered;
4950 	}
4951 
4952 	dev =  __dev_get_by_index(net, ifm->ifa_index);
4953 	if (!dev) {
4954 		NL_SET_ERR_MSG_MOD(extack, "Unable to find the interface");
4955 		return -ENODEV;
4956 	}
4957 
4958 	if (tb[IFA_FLAGS])
4959 		cfg.ifa_flags = nla_get_u32(tb[IFA_FLAGS]);
4960 	else
4961 		cfg.ifa_flags = ifm->ifa_flags;
4962 
4963 	/* We ignore other flags so far. */
4964 	cfg.ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS |
4965 			 IFA_F_MANAGETEMPADDR | IFA_F_NOPREFIXROUTE |
4966 			 IFA_F_MCAUTOJOIN | IFA_F_OPTIMISTIC;
4967 
4968 	idev = ipv6_find_idev(dev);
4969 	if (IS_ERR(idev))
4970 		return PTR_ERR(idev);
4971 
4972 	if (!ipv6_allow_optimistic_dad(net, idev))
4973 		cfg.ifa_flags &= ~IFA_F_OPTIMISTIC;
4974 
4975 	if (cfg.ifa_flags & IFA_F_NODAD &&
4976 	    cfg.ifa_flags & IFA_F_OPTIMISTIC) {
4977 		NL_SET_ERR_MSG(extack, "IFA_F_NODAD and IFA_F_OPTIMISTIC are mutually exclusive");
4978 		return -EINVAL;
4979 	}
4980 
4981 	ifa = ipv6_get_ifaddr(net, cfg.pfx, dev, 1);
4982 	if (!ifa) {
4983 		/*
4984 		 * It would be best to check for !NLM_F_CREATE here but
4985 		 * userspace already relies on not having to provide this.
4986 		 */
4987 		return inet6_addr_add(net, ifm->ifa_index, &cfg, extack);
4988 	}
4989 
4990 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
4991 	    !(nlh->nlmsg_flags & NLM_F_REPLACE)) {
4992 		NL_SET_ERR_MSG_MOD(extack, "address already assigned");
4993 		err = -EEXIST;
4994 	} else {
4995 		err = inet6_addr_modify(net, ifa, &cfg);
4996 	}
4997 
4998 	in6_ifa_put(ifa);
4999 
5000 	return err;
5001 }
5002 
5003 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
5004 			  u8 scope, int ifindex)
5005 {
5006 	struct ifaddrmsg *ifm;
5007 
5008 	ifm = nlmsg_data(nlh);
5009 	ifm->ifa_family = AF_INET6;
5010 	ifm->ifa_prefixlen = prefixlen;
5011 	ifm->ifa_flags = flags;
5012 	ifm->ifa_scope = scope;
5013 	ifm->ifa_index = ifindex;
5014 }
5015 
5016 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
5017 			 unsigned long tstamp, u32 preferred, u32 valid)
5018 {
5019 	struct ifa_cacheinfo ci;
5020 
5021 	ci.cstamp = cstamp_delta(cstamp);
5022 	ci.tstamp = cstamp_delta(tstamp);
5023 	ci.ifa_prefered = preferred;
5024 	ci.ifa_valid = valid;
5025 
5026 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
5027 }
5028 
5029 static inline int rt_scope(int ifa_scope)
5030 {
5031 	if (ifa_scope & IFA_HOST)
5032 		return RT_SCOPE_HOST;
5033 	else if (ifa_scope & IFA_LINK)
5034 		return RT_SCOPE_LINK;
5035 	else if (ifa_scope & IFA_SITE)
5036 		return RT_SCOPE_SITE;
5037 	else
5038 		return RT_SCOPE_UNIVERSE;
5039 }
5040 
5041 static inline int inet6_ifaddr_msgsize(void)
5042 {
5043 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
5044 	       + nla_total_size(16) /* IFA_LOCAL */
5045 	       + nla_total_size(16) /* IFA_ADDRESS */
5046 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
5047 	       + nla_total_size(4)  /* IFA_FLAGS */
5048 	       + nla_total_size(1)  /* IFA_PROTO */
5049 	       + nla_total_size(4)  /* IFA_RT_PRIORITY */;
5050 }
5051 
5052 enum addr_type_t {
5053 	UNICAST_ADDR,
5054 	MULTICAST_ADDR,
5055 	ANYCAST_ADDR,
5056 };
5057 
5058 struct inet6_fill_args {
5059 	u32 portid;
5060 	u32 seq;
5061 	int event;
5062 	unsigned int flags;
5063 	int netnsid;
5064 	int ifindex;
5065 	enum addr_type_t type;
5066 };
5067 
5068 static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
5069 			     struct inet6_fill_args *args)
5070 {
5071 	struct nlmsghdr  *nlh;
5072 	u32 preferred, valid;
5073 
5074 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5075 			sizeof(struct ifaddrmsg), args->flags);
5076 	if (!nlh)
5077 		return -EMSGSIZE;
5078 
5079 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
5080 		      ifa->idev->dev->ifindex);
5081 
5082 	if (args->netnsid >= 0 &&
5083 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
5084 		goto error;
5085 
5086 	spin_lock_bh(&ifa->lock);
5087 	if (!((ifa->flags&IFA_F_PERMANENT) &&
5088 	      (ifa->prefered_lft == INFINITY_LIFE_TIME))) {
5089 		preferred = ifa->prefered_lft;
5090 		valid = ifa->valid_lft;
5091 		if (preferred != INFINITY_LIFE_TIME) {
5092 			long tval = (jiffies - ifa->tstamp)/HZ;
5093 			if (preferred > tval)
5094 				preferred -= tval;
5095 			else
5096 				preferred = 0;
5097 			if (valid != INFINITY_LIFE_TIME) {
5098 				if (valid > tval)
5099 					valid -= tval;
5100 				else
5101 					valid = 0;
5102 			}
5103 		}
5104 	} else {
5105 		preferred = INFINITY_LIFE_TIME;
5106 		valid = INFINITY_LIFE_TIME;
5107 	}
5108 	spin_unlock_bh(&ifa->lock);
5109 
5110 	if (!ipv6_addr_any(&ifa->peer_addr)) {
5111 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
5112 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
5113 			goto error;
5114 	} else
5115 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
5116 			goto error;
5117 
5118 	if (ifa->rt_priority &&
5119 	    nla_put_u32(skb, IFA_RT_PRIORITY, ifa->rt_priority))
5120 		goto error;
5121 
5122 	if (put_cacheinfo(skb, ifa->cstamp, ifa->tstamp, preferred, valid) < 0)
5123 		goto error;
5124 
5125 	if (nla_put_u32(skb, IFA_FLAGS, ifa->flags) < 0)
5126 		goto error;
5127 
5128 	if (ifa->ifa_proto &&
5129 	    nla_put_u8(skb, IFA_PROTO, ifa->ifa_proto))
5130 		goto error;
5131 
5132 	nlmsg_end(skb, nlh);
5133 	return 0;
5134 
5135 error:
5136 	nlmsg_cancel(skb, nlh);
5137 	return -EMSGSIZE;
5138 }
5139 
5140 static int inet6_fill_ifmcaddr(struct sk_buff *skb, struct ifmcaddr6 *ifmca,
5141 			       struct inet6_fill_args *args)
5142 {
5143 	struct nlmsghdr  *nlh;
5144 	u8 scope = RT_SCOPE_UNIVERSE;
5145 	int ifindex = ifmca->idev->dev->ifindex;
5146 
5147 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
5148 		scope = RT_SCOPE_SITE;
5149 
5150 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5151 			sizeof(struct ifaddrmsg), args->flags);
5152 	if (!nlh)
5153 		return -EMSGSIZE;
5154 
5155 	if (args->netnsid >= 0 &&
5156 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) {
5157 		nlmsg_cancel(skb, nlh);
5158 		return -EMSGSIZE;
5159 	}
5160 
5161 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5162 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
5163 	    put_cacheinfo(skb, ifmca->mca_cstamp, ifmca->mca_tstamp,
5164 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5165 		nlmsg_cancel(skb, nlh);
5166 		return -EMSGSIZE;
5167 	}
5168 
5169 	nlmsg_end(skb, nlh);
5170 	return 0;
5171 }
5172 
5173 static int inet6_fill_ifacaddr(struct sk_buff *skb, struct ifacaddr6 *ifaca,
5174 			       struct inet6_fill_args *args)
5175 {
5176 	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
5177 	int ifindex = dev ? dev->ifindex : 1;
5178 	struct nlmsghdr  *nlh;
5179 	u8 scope = RT_SCOPE_UNIVERSE;
5180 
5181 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
5182 		scope = RT_SCOPE_SITE;
5183 
5184 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5185 			sizeof(struct ifaddrmsg), args->flags);
5186 	if (!nlh)
5187 		return -EMSGSIZE;
5188 
5189 	if (args->netnsid >= 0 &&
5190 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) {
5191 		nlmsg_cancel(skb, nlh);
5192 		return -EMSGSIZE;
5193 	}
5194 
5195 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5196 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
5197 	    put_cacheinfo(skb, ifaca->aca_cstamp, ifaca->aca_tstamp,
5198 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5199 		nlmsg_cancel(skb, nlh);
5200 		return -EMSGSIZE;
5201 	}
5202 
5203 	nlmsg_end(skb, nlh);
5204 	return 0;
5205 }
5206 
5207 /* called with rcu_read_lock() */
5208 static int in6_dump_addrs(struct inet6_dev *idev, struct sk_buff *skb,
5209 			  struct netlink_callback *cb, int s_ip_idx,
5210 			  struct inet6_fill_args *fillargs)
5211 {
5212 	struct ifmcaddr6 *ifmca;
5213 	struct ifacaddr6 *ifaca;
5214 	int ip_idx = 0;
5215 	int err = 1;
5216 
5217 	read_lock_bh(&idev->lock);
5218 	switch (fillargs->type) {
5219 	case UNICAST_ADDR: {
5220 		struct inet6_ifaddr *ifa;
5221 		fillargs->event = RTM_NEWADDR;
5222 
5223 		/* unicast address incl. temp addr */
5224 		list_for_each_entry(ifa, &idev->addr_list, if_list) {
5225 			if (ip_idx < s_ip_idx)
5226 				goto next;
5227 			err = inet6_fill_ifaddr(skb, ifa, fillargs);
5228 			if (err < 0)
5229 				break;
5230 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
5231 next:
5232 			ip_idx++;
5233 		}
5234 		break;
5235 	}
5236 	case MULTICAST_ADDR:
5237 		read_unlock_bh(&idev->lock);
5238 		fillargs->event = RTM_GETMULTICAST;
5239 
5240 		/* multicast address */
5241 		for (ifmca = rtnl_dereference(idev->mc_list);
5242 		     ifmca;
5243 		     ifmca = rtnl_dereference(ifmca->next), ip_idx++) {
5244 			if (ip_idx < s_ip_idx)
5245 				continue;
5246 			err = inet6_fill_ifmcaddr(skb, ifmca, fillargs);
5247 			if (err < 0)
5248 				break;
5249 		}
5250 		read_lock_bh(&idev->lock);
5251 		break;
5252 	case ANYCAST_ADDR:
5253 		fillargs->event = RTM_GETANYCAST;
5254 		/* anycast address */
5255 		for (ifaca = idev->ac_list; ifaca;
5256 		     ifaca = ifaca->aca_next, ip_idx++) {
5257 			if (ip_idx < s_ip_idx)
5258 				continue;
5259 			err = inet6_fill_ifacaddr(skb, ifaca, fillargs);
5260 			if (err < 0)
5261 				break;
5262 		}
5263 		break;
5264 	default:
5265 		break;
5266 	}
5267 	read_unlock_bh(&idev->lock);
5268 	cb->args[2] = ip_idx;
5269 	return err;
5270 }
5271 
5272 static int inet6_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
5273 				       struct inet6_fill_args *fillargs,
5274 				       struct net **tgt_net, struct sock *sk,
5275 				       struct netlink_callback *cb)
5276 {
5277 	struct netlink_ext_ack *extack = cb->extack;
5278 	struct nlattr *tb[IFA_MAX+1];
5279 	struct ifaddrmsg *ifm;
5280 	int err, i;
5281 
5282 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5283 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for address dump request");
5284 		return -EINVAL;
5285 	}
5286 
5287 	ifm = nlmsg_data(nlh);
5288 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5289 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address dump request");
5290 		return -EINVAL;
5291 	}
5292 
5293 	fillargs->ifindex = ifm->ifa_index;
5294 	if (fillargs->ifindex) {
5295 		cb->answer_flags |= NLM_F_DUMP_FILTERED;
5296 		fillargs->flags |= NLM_F_DUMP_FILTERED;
5297 	}
5298 
5299 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5300 					    ifa_ipv6_policy, extack);
5301 	if (err < 0)
5302 		return err;
5303 
5304 	for (i = 0; i <= IFA_MAX; ++i) {
5305 		if (!tb[i])
5306 			continue;
5307 
5308 		if (i == IFA_TARGET_NETNSID) {
5309 			struct net *net;
5310 
5311 			fillargs->netnsid = nla_get_s32(tb[i]);
5312 			net = rtnl_get_net_ns_capable(sk, fillargs->netnsid);
5313 			if (IS_ERR(net)) {
5314 				fillargs->netnsid = -1;
5315 				NL_SET_ERR_MSG_MOD(extack, "Invalid target network namespace id");
5316 				return PTR_ERR(net);
5317 			}
5318 			*tgt_net = net;
5319 		} else {
5320 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request");
5321 			return -EINVAL;
5322 		}
5323 	}
5324 
5325 	return 0;
5326 }
5327 
5328 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
5329 			   enum addr_type_t type)
5330 {
5331 	const struct nlmsghdr *nlh = cb->nlh;
5332 	struct inet6_fill_args fillargs = {
5333 		.portid = NETLINK_CB(cb->skb).portid,
5334 		.seq = cb->nlh->nlmsg_seq,
5335 		.flags = NLM_F_MULTI,
5336 		.netnsid = -1,
5337 		.type = type,
5338 	};
5339 	struct net *tgt_net = sock_net(skb->sk);
5340 	int idx, s_idx, s_ip_idx;
5341 	int h, s_h;
5342 	struct net_device *dev;
5343 	struct inet6_dev *idev;
5344 	struct hlist_head *head;
5345 	int err = 0;
5346 
5347 	s_h = cb->args[0];
5348 	s_idx = idx = cb->args[1];
5349 	s_ip_idx = cb->args[2];
5350 
5351 	if (cb->strict_check) {
5352 		err = inet6_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
5353 						  skb->sk, cb);
5354 		if (err < 0)
5355 			goto put_tgt_net;
5356 
5357 		err = 0;
5358 		if (fillargs.ifindex) {
5359 			dev = __dev_get_by_index(tgt_net, fillargs.ifindex);
5360 			if (!dev) {
5361 				err = -ENODEV;
5362 				goto put_tgt_net;
5363 			}
5364 			idev = __in6_dev_get(dev);
5365 			if (idev) {
5366 				err = in6_dump_addrs(idev, skb, cb, s_ip_idx,
5367 						     &fillargs);
5368 				if (err > 0)
5369 					err = 0;
5370 			}
5371 			goto put_tgt_net;
5372 		}
5373 	}
5374 
5375 	rcu_read_lock();
5376 	cb->seq = inet6_base_seq(tgt_net);
5377 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
5378 		idx = 0;
5379 		head = &tgt_net->dev_index_head[h];
5380 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
5381 			if (idx < s_idx)
5382 				goto cont;
5383 			if (h > s_h || idx > s_idx)
5384 				s_ip_idx = 0;
5385 			idev = __in6_dev_get(dev);
5386 			if (!idev)
5387 				goto cont;
5388 
5389 			if (in6_dump_addrs(idev, skb, cb, s_ip_idx,
5390 					   &fillargs) < 0)
5391 				goto done;
5392 cont:
5393 			idx++;
5394 		}
5395 	}
5396 done:
5397 	rcu_read_unlock();
5398 	cb->args[0] = h;
5399 	cb->args[1] = idx;
5400 put_tgt_net:
5401 	if (fillargs.netnsid >= 0)
5402 		put_net(tgt_net);
5403 
5404 	return skb->len ? : err;
5405 }
5406 
5407 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
5408 {
5409 	enum addr_type_t type = UNICAST_ADDR;
5410 
5411 	return inet6_dump_addr(skb, cb, type);
5412 }
5413 
5414 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
5415 {
5416 	enum addr_type_t type = MULTICAST_ADDR;
5417 
5418 	return inet6_dump_addr(skb, cb, type);
5419 }
5420 
5421 
5422 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
5423 {
5424 	enum addr_type_t type = ANYCAST_ADDR;
5425 
5426 	return inet6_dump_addr(skb, cb, type);
5427 }
5428 
5429 static int inet6_rtm_valid_getaddr_req(struct sk_buff *skb,
5430 				       const struct nlmsghdr *nlh,
5431 				       struct nlattr **tb,
5432 				       struct netlink_ext_ack *extack)
5433 {
5434 	struct ifaddrmsg *ifm;
5435 	int i, err;
5436 
5437 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5438 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for get address request");
5439 		return -EINVAL;
5440 	}
5441 
5442 	if (!netlink_strict_get_check(skb))
5443 		return nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
5444 					      ifa_ipv6_policy, extack);
5445 
5446 	ifm = nlmsg_data(nlh);
5447 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5448 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get address request");
5449 		return -EINVAL;
5450 	}
5451 
5452 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5453 					    ifa_ipv6_policy, extack);
5454 	if (err)
5455 		return err;
5456 
5457 	for (i = 0; i <= IFA_MAX; i++) {
5458 		if (!tb[i])
5459 			continue;
5460 
5461 		switch (i) {
5462 		case IFA_TARGET_NETNSID:
5463 		case IFA_ADDRESS:
5464 		case IFA_LOCAL:
5465 			break;
5466 		default:
5467 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get address request");
5468 			return -EINVAL;
5469 		}
5470 	}
5471 
5472 	return 0;
5473 }
5474 
5475 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5476 			     struct netlink_ext_ack *extack)
5477 {
5478 	struct net *tgt_net = sock_net(in_skb->sk);
5479 	struct inet6_fill_args fillargs = {
5480 		.portid = NETLINK_CB(in_skb).portid,
5481 		.seq = nlh->nlmsg_seq,
5482 		.event = RTM_NEWADDR,
5483 		.flags = 0,
5484 		.netnsid = -1,
5485 	};
5486 	struct ifaddrmsg *ifm;
5487 	struct nlattr *tb[IFA_MAX+1];
5488 	struct in6_addr *addr = NULL, *peer;
5489 	struct net_device *dev = NULL;
5490 	struct inet6_ifaddr *ifa;
5491 	struct sk_buff *skb;
5492 	int err;
5493 
5494 	err = inet6_rtm_valid_getaddr_req(in_skb, nlh, tb, extack);
5495 	if (err < 0)
5496 		return err;
5497 
5498 	if (tb[IFA_TARGET_NETNSID]) {
5499 		fillargs.netnsid = nla_get_s32(tb[IFA_TARGET_NETNSID]);
5500 
5501 		tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(in_skb).sk,
5502 						  fillargs.netnsid);
5503 		if (IS_ERR(tgt_net))
5504 			return PTR_ERR(tgt_net);
5505 	}
5506 
5507 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
5508 	if (!addr) {
5509 		err = -EINVAL;
5510 		goto errout;
5511 	}
5512 	ifm = nlmsg_data(nlh);
5513 	if (ifm->ifa_index)
5514 		dev = dev_get_by_index(tgt_net, ifm->ifa_index);
5515 
5516 	ifa = ipv6_get_ifaddr(tgt_net, addr, dev, 1);
5517 	if (!ifa) {
5518 		err = -EADDRNOTAVAIL;
5519 		goto errout;
5520 	}
5521 
5522 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
5523 	if (!skb) {
5524 		err = -ENOBUFS;
5525 		goto errout_ifa;
5526 	}
5527 
5528 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5529 	if (err < 0) {
5530 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5531 		WARN_ON(err == -EMSGSIZE);
5532 		kfree_skb(skb);
5533 		goto errout_ifa;
5534 	}
5535 	err = rtnl_unicast(skb, tgt_net, NETLINK_CB(in_skb).portid);
5536 errout_ifa:
5537 	in6_ifa_put(ifa);
5538 errout:
5539 	dev_put(dev);
5540 	if (fillargs.netnsid >= 0)
5541 		put_net(tgt_net);
5542 
5543 	return err;
5544 }
5545 
5546 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
5547 {
5548 	struct sk_buff *skb;
5549 	struct net *net = dev_net(ifa->idev->dev);
5550 	struct inet6_fill_args fillargs = {
5551 		.portid = 0,
5552 		.seq = 0,
5553 		.event = event,
5554 		.flags = 0,
5555 		.netnsid = -1,
5556 	};
5557 	int err = -ENOBUFS;
5558 
5559 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
5560 	if (!skb)
5561 		goto errout;
5562 
5563 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5564 	if (err < 0) {
5565 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5566 		WARN_ON(err == -EMSGSIZE);
5567 		kfree_skb(skb);
5568 		goto errout;
5569 	}
5570 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5571 	return;
5572 errout:
5573 	if (err < 0)
5574 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5575 }
5576 
5577 static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
5578 				__s32 *array, int bytes)
5579 {
5580 	BUG_ON(bytes < (DEVCONF_MAX * 4));
5581 
5582 	memset(array, 0, bytes);
5583 	array[DEVCONF_FORWARDING] = cnf->forwarding;
5584 	array[DEVCONF_HOPLIMIT] = cnf->hop_limit;
5585 	array[DEVCONF_MTU6] = cnf->mtu6;
5586 	array[DEVCONF_ACCEPT_RA] = cnf->accept_ra;
5587 	array[DEVCONF_ACCEPT_REDIRECTS] = cnf->accept_redirects;
5588 	array[DEVCONF_AUTOCONF] = cnf->autoconf;
5589 	array[DEVCONF_DAD_TRANSMITS] = cnf->dad_transmits;
5590 	array[DEVCONF_RTR_SOLICITS] = cnf->rtr_solicits;
5591 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5592 		jiffies_to_msecs(cnf->rtr_solicit_interval);
5593 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5594 		jiffies_to_msecs(cnf->rtr_solicit_max_interval);
5595 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5596 		jiffies_to_msecs(cnf->rtr_solicit_delay);
5597 	array[DEVCONF_FORCE_MLD_VERSION] = cnf->force_mld_version;
5598 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5599 		jiffies_to_msecs(cnf->mldv1_unsolicited_report_interval);
5600 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5601 		jiffies_to_msecs(cnf->mldv2_unsolicited_report_interval);
5602 	array[DEVCONF_USE_TEMPADDR] = cnf->use_tempaddr;
5603 	array[DEVCONF_TEMP_VALID_LFT] = cnf->temp_valid_lft;
5604 	array[DEVCONF_TEMP_PREFERED_LFT] = cnf->temp_prefered_lft;
5605 	array[DEVCONF_REGEN_MAX_RETRY] = cnf->regen_max_retry;
5606 	array[DEVCONF_MAX_DESYNC_FACTOR] = cnf->max_desync_factor;
5607 	array[DEVCONF_MAX_ADDRESSES] = cnf->max_addresses;
5608 	array[DEVCONF_ACCEPT_RA_DEFRTR] = cnf->accept_ra_defrtr;
5609 	array[DEVCONF_RA_DEFRTR_METRIC] = cnf->ra_defrtr_metric;
5610 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] = cnf->accept_ra_min_hop_limit;
5611 	array[DEVCONF_ACCEPT_RA_PINFO] = cnf->accept_ra_pinfo;
5612 #ifdef CONFIG_IPV6_ROUTER_PREF
5613 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = cnf->accept_ra_rtr_pref;
5614 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5615 		jiffies_to_msecs(cnf->rtr_probe_interval);
5616 #ifdef CONFIG_IPV6_ROUTE_INFO
5617 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] = cnf->accept_ra_rt_info_min_plen;
5618 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] = cnf->accept_ra_rt_info_max_plen;
5619 #endif
5620 #endif
5621 	array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
5622 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
5623 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5624 	array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
5625 	array[DEVCONF_USE_OPTIMISTIC] = cnf->use_optimistic;
5626 #endif
5627 #ifdef CONFIG_IPV6_MROUTE
5628 	array[DEVCONF_MC_FORWARDING] = atomic_read(&cnf->mc_forwarding);
5629 #endif
5630 	array[DEVCONF_DISABLE_IPV6] = cnf->disable_ipv6;
5631 	array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad;
5632 	array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao;
5633 	array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify;
5634 	array[DEVCONF_SUPPRESS_FRAG_NDISC] = cnf->suppress_frag_ndisc;
5635 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
5636 	array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
5637 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] = cnf->ignore_routes_with_linkdown;
5638 	/* we omit DEVCONF_STABLE_SECRET for now */
5639 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
5640 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
5641 	array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
5642 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = cnf->keep_addr_on_down;
5643 	array[DEVCONF_SEG6_ENABLED] = cnf->seg6_enabled;
5644 #ifdef CONFIG_IPV6_SEG6_HMAC
5645 	array[DEVCONF_SEG6_REQUIRE_HMAC] = cnf->seg6_require_hmac;
5646 #endif
5647 	array[DEVCONF_ENHANCED_DAD] = cnf->enhanced_dad;
5648 	array[DEVCONF_ADDR_GEN_MODE] = cnf->addr_gen_mode;
5649 	array[DEVCONF_DISABLE_POLICY] = cnf->disable_policy;
5650 	array[DEVCONF_NDISC_TCLASS] = cnf->ndisc_tclass;
5651 	array[DEVCONF_RPL_SEG_ENABLED] = cnf->rpl_seg_enabled;
5652 	array[DEVCONF_IOAM6_ENABLED] = cnf->ioam6_enabled;
5653 	array[DEVCONF_IOAM6_ID] = cnf->ioam6_id;
5654 	array[DEVCONF_IOAM6_ID_WIDE] = cnf->ioam6_id_wide;
5655 	array[DEVCONF_NDISC_EVICT_NOCARRIER] = cnf->ndisc_evict_nocarrier;
5656 	array[DEVCONF_ACCEPT_UNTRACKED_NA] = cnf->accept_untracked_na;
5657 	array[DEVCONF_ACCEPT_RA_MIN_LFT] = cnf->accept_ra_min_lft;
5658 }
5659 
5660 static inline size_t inet6_ifla6_size(void)
5661 {
5662 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5663 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5664 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5665 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5666 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5667 	     + nla_total_size(sizeof(struct in6_addr)) /* IFLA_INET6_TOKEN */
5668 	     + nla_total_size(1) /* IFLA_INET6_ADDR_GEN_MODE */
5669 	     + nla_total_size(4) /* IFLA_INET6_RA_MTU */
5670 	     + 0;
5671 }
5672 
5673 static inline size_t inet6_if_nlmsg_size(void)
5674 {
5675 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5676 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5677 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5678 	       + nla_total_size(4) /* IFLA_MTU */
5679 	       + nla_total_size(4) /* IFLA_LINK */
5680 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5681 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5682 }
5683 
5684 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5685 					int bytes)
5686 {
5687 	int i;
5688 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5689 	BUG_ON(pad < 0);
5690 
5691 	/* Use put_unaligned() because stats may not be aligned for u64. */
5692 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5693 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5694 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5695 
5696 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5697 }
5698 
5699 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5700 					int bytes, size_t syncpoff)
5701 {
5702 	int i, c;
5703 	u64 buff[IPSTATS_MIB_MAX];
5704 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5705 
5706 	BUG_ON(pad < 0);
5707 
5708 	memset(buff, 0, sizeof(buff));
5709 	buff[0] = IPSTATS_MIB_MAX;
5710 
5711 	for_each_possible_cpu(c) {
5712 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5713 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5714 	}
5715 
5716 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5717 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5718 }
5719 
5720 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5721 			     int bytes)
5722 {
5723 	switch (attrtype) {
5724 	case IFLA_INET6_STATS:
5725 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5726 				     offsetof(struct ipstats_mib, syncp));
5727 		break;
5728 	case IFLA_INET6_ICMP6STATS:
5729 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5730 		break;
5731 	}
5732 }
5733 
5734 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5735 				  u32 ext_filter_mask)
5736 {
5737 	struct nlattr *nla;
5738 	struct ifla_cacheinfo ci;
5739 
5740 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, idev->if_flags))
5741 		goto nla_put_failure;
5742 	ci.max_reasm_len = IPV6_MAXPLEN;
5743 	ci.tstamp = cstamp_delta(idev->tstamp);
5744 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5745 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5746 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5747 		goto nla_put_failure;
5748 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5749 	if (!nla)
5750 		goto nla_put_failure;
5751 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5752 
5753 	/* XXX - MC not implemented */
5754 
5755 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5756 		return 0;
5757 
5758 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5759 	if (!nla)
5760 		goto nla_put_failure;
5761 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5762 
5763 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5764 	if (!nla)
5765 		goto nla_put_failure;
5766 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5767 
5768 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5769 	if (!nla)
5770 		goto nla_put_failure;
5771 	read_lock_bh(&idev->lock);
5772 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5773 	read_unlock_bh(&idev->lock);
5774 
5775 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE, idev->cnf.addr_gen_mode))
5776 		goto nla_put_failure;
5777 
5778 	if (idev->ra_mtu &&
5779 	    nla_put_u32(skb, IFLA_INET6_RA_MTU, idev->ra_mtu))
5780 		goto nla_put_failure;
5781 
5782 	return 0;
5783 
5784 nla_put_failure:
5785 	return -EMSGSIZE;
5786 }
5787 
5788 static size_t inet6_get_link_af_size(const struct net_device *dev,
5789 				     u32 ext_filter_mask)
5790 {
5791 	if (!__in6_dev_get(dev))
5792 		return 0;
5793 
5794 	return inet6_ifla6_size();
5795 }
5796 
5797 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5798 			      u32 ext_filter_mask)
5799 {
5800 	struct inet6_dev *idev = __in6_dev_get(dev);
5801 
5802 	if (!idev)
5803 		return -ENODATA;
5804 
5805 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5806 		return -EMSGSIZE;
5807 
5808 	return 0;
5809 }
5810 
5811 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token,
5812 			     struct netlink_ext_ack *extack)
5813 {
5814 	struct inet6_ifaddr *ifp;
5815 	struct net_device *dev = idev->dev;
5816 	bool clear_token, update_rs = false;
5817 	struct in6_addr ll_addr;
5818 
5819 	ASSERT_RTNL();
5820 
5821 	if (!token)
5822 		return -EINVAL;
5823 
5824 	if (dev->flags & IFF_LOOPBACK) {
5825 		NL_SET_ERR_MSG_MOD(extack, "Device is loopback");
5826 		return -EINVAL;
5827 	}
5828 
5829 	if (dev->flags & IFF_NOARP) {
5830 		NL_SET_ERR_MSG_MOD(extack,
5831 				   "Device does not do neighbour discovery");
5832 		return -EINVAL;
5833 	}
5834 
5835 	if (!ipv6_accept_ra(idev)) {
5836 		NL_SET_ERR_MSG_MOD(extack,
5837 				   "Router advertisement is disabled on device");
5838 		return -EINVAL;
5839 	}
5840 
5841 	if (idev->cnf.rtr_solicits == 0) {
5842 		NL_SET_ERR_MSG(extack,
5843 			       "Router solicitation is disabled on device");
5844 		return -EINVAL;
5845 	}
5846 
5847 	write_lock_bh(&idev->lock);
5848 
5849 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5850 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5851 
5852 	write_unlock_bh(&idev->lock);
5853 
5854 	clear_token = ipv6_addr_any(token);
5855 	if (clear_token)
5856 		goto update_lft;
5857 
5858 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5859 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5860 			     IFA_F_OPTIMISTIC)) {
5861 		/* If we're not ready, then normal ifup will take care
5862 		 * of this. Otherwise, we need to request our rs here.
5863 		 */
5864 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5865 		update_rs = true;
5866 	}
5867 
5868 update_lft:
5869 	write_lock_bh(&idev->lock);
5870 
5871 	if (update_rs) {
5872 		idev->if_flags |= IF_RS_SENT;
5873 		idev->rs_interval = rfc3315_s14_backoff_init(
5874 			idev->cnf.rtr_solicit_interval);
5875 		idev->rs_probes = 1;
5876 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5877 	}
5878 
5879 	/* Well, that's kinda nasty ... */
5880 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5881 		spin_lock(&ifp->lock);
5882 		if (ifp->tokenized) {
5883 			ifp->valid_lft = 0;
5884 			ifp->prefered_lft = 0;
5885 		}
5886 		spin_unlock(&ifp->lock);
5887 	}
5888 
5889 	write_unlock_bh(&idev->lock);
5890 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5891 	addrconf_verify_rtnl(dev_net(dev));
5892 	return 0;
5893 }
5894 
5895 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5896 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5897 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5898 	[IFLA_INET6_RA_MTU]		= { .type = NLA_REJECT,
5899 					    .reject_message =
5900 						"IFLA_INET6_RA_MTU can not be set" },
5901 };
5902 
5903 static int check_addr_gen_mode(int mode)
5904 {
5905 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5906 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5907 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5908 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5909 		return -EINVAL;
5910 	return 1;
5911 }
5912 
5913 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5914 				int mode)
5915 {
5916 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5917 	    !idev->cnf.stable_secret.initialized &&
5918 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5919 		return -EINVAL;
5920 	return 1;
5921 }
5922 
5923 static int inet6_validate_link_af(const struct net_device *dev,
5924 				  const struct nlattr *nla,
5925 				  struct netlink_ext_ack *extack)
5926 {
5927 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5928 	struct inet6_dev *idev = NULL;
5929 	int err;
5930 
5931 	if (dev) {
5932 		idev = __in6_dev_get(dev);
5933 		if (!idev)
5934 			return -EAFNOSUPPORT;
5935 	}
5936 
5937 	err = nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla,
5938 					  inet6_af_policy, extack);
5939 	if (err)
5940 		return err;
5941 
5942 	if (!tb[IFLA_INET6_TOKEN] && !tb[IFLA_INET6_ADDR_GEN_MODE])
5943 		return -EINVAL;
5944 
5945 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5946 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5947 
5948 		if (check_addr_gen_mode(mode) < 0)
5949 			return -EINVAL;
5950 		if (dev && check_stable_privacy(idev, dev_net(dev), mode) < 0)
5951 			return -EINVAL;
5952 	}
5953 
5954 	return 0;
5955 }
5956 
5957 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla,
5958 			     struct netlink_ext_ack *extack)
5959 {
5960 	struct inet6_dev *idev = __in6_dev_get(dev);
5961 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5962 	int err;
5963 
5964 	if (!idev)
5965 		return -EAFNOSUPPORT;
5966 
5967 	if (nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
5968 		return -EINVAL;
5969 
5970 	if (tb[IFLA_INET6_TOKEN]) {
5971 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]),
5972 					extack);
5973 		if (err)
5974 			return err;
5975 	}
5976 
5977 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
5978 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
5979 
5980 		idev->cnf.addr_gen_mode = mode;
5981 	}
5982 
5983 	return 0;
5984 }
5985 
5986 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
5987 			     u32 portid, u32 seq, int event, unsigned int flags)
5988 {
5989 	struct net_device *dev = idev->dev;
5990 	struct ifinfomsg *hdr;
5991 	struct nlmsghdr *nlh;
5992 	void *protoinfo;
5993 
5994 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
5995 	if (!nlh)
5996 		return -EMSGSIZE;
5997 
5998 	hdr = nlmsg_data(nlh);
5999 	hdr->ifi_family = AF_INET6;
6000 	hdr->__ifi_pad = 0;
6001 	hdr->ifi_type = dev->type;
6002 	hdr->ifi_index = dev->ifindex;
6003 	hdr->ifi_flags = dev_get_flags(dev);
6004 	hdr->ifi_change = 0;
6005 
6006 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
6007 	    (dev->addr_len &&
6008 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
6009 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
6010 	    (dev->ifindex != dev_get_iflink(dev) &&
6011 	     nla_put_u32(skb, IFLA_LINK, dev_get_iflink(dev))) ||
6012 	    nla_put_u8(skb, IFLA_OPERSTATE,
6013 		       netif_running(dev) ? dev->operstate : IF_OPER_DOWN))
6014 		goto nla_put_failure;
6015 	protoinfo = nla_nest_start_noflag(skb, IFLA_PROTINFO);
6016 	if (!protoinfo)
6017 		goto nla_put_failure;
6018 
6019 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
6020 		goto nla_put_failure;
6021 
6022 	nla_nest_end(skb, protoinfo);
6023 	nlmsg_end(skb, nlh);
6024 	return 0;
6025 
6026 nla_put_failure:
6027 	nlmsg_cancel(skb, nlh);
6028 	return -EMSGSIZE;
6029 }
6030 
6031 static int inet6_valid_dump_ifinfo(const struct nlmsghdr *nlh,
6032 				   struct netlink_ext_ack *extack)
6033 {
6034 	struct ifinfomsg *ifm;
6035 
6036 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
6037 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for link dump request");
6038 		return -EINVAL;
6039 	}
6040 
6041 	if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
6042 		NL_SET_ERR_MSG_MOD(extack, "Invalid data after header");
6043 		return -EINVAL;
6044 	}
6045 
6046 	ifm = nlmsg_data(nlh);
6047 	if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
6048 	    ifm->ifi_change || ifm->ifi_index) {
6049 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for dump request");
6050 		return -EINVAL;
6051 	}
6052 
6053 	return 0;
6054 }
6055 
6056 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
6057 {
6058 	struct net *net = sock_net(skb->sk);
6059 	int h, s_h;
6060 	int idx = 0, s_idx;
6061 	struct net_device *dev;
6062 	struct inet6_dev *idev;
6063 	struct hlist_head *head;
6064 
6065 	/* only requests using strict checking can pass data to
6066 	 * influence the dump
6067 	 */
6068 	if (cb->strict_check) {
6069 		int err = inet6_valid_dump_ifinfo(cb->nlh, cb->extack);
6070 
6071 		if (err < 0)
6072 			return err;
6073 	}
6074 
6075 	s_h = cb->args[0];
6076 	s_idx = cb->args[1];
6077 
6078 	rcu_read_lock();
6079 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
6080 		idx = 0;
6081 		head = &net->dev_index_head[h];
6082 		hlist_for_each_entry_rcu(dev, head, index_hlist) {
6083 			if (idx < s_idx)
6084 				goto cont;
6085 			idev = __in6_dev_get(dev);
6086 			if (!idev)
6087 				goto cont;
6088 			if (inet6_fill_ifinfo(skb, idev,
6089 					      NETLINK_CB(cb->skb).portid,
6090 					      cb->nlh->nlmsg_seq,
6091 					      RTM_NEWLINK, NLM_F_MULTI) < 0)
6092 				goto out;
6093 cont:
6094 			idx++;
6095 		}
6096 	}
6097 out:
6098 	rcu_read_unlock();
6099 	cb->args[1] = idx;
6100 	cb->args[0] = h;
6101 
6102 	return skb->len;
6103 }
6104 
6105 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
6106 {
6107 	struct sk_buff *skb;
6108 	struct net *net = dev_net(idev->dev);
6109 	int err = -ENOBUFS;
6110 
6111 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
6112 	if (!skb)
6113 		goto errout;
6114 
6115 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
6116 	if (err < 0) {
6117 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
6118 		WARN_ON(err == -EMSGSIZE);
6119 		kfree_skb(skb);
6120 		goto errout;
6121 	}
6122 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
6123 	return;
6124 errout:
6125 	if (err < 0)
6126 		rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
6127 }
6128 
6129 static inline size_t inet6_prefix_nlmsg_size(void)
6130 {
6131 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
6132 	       + nla_total_size(sizeof(struct in6_addr))
6133 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
6134 }
6135 
6136 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
6137 			     struct prefix_info *pinfo, u32 portid, u32 seq,
6138 			     int event, unsigned int flags)
6139 {
6140 	struct prefixmsg *pmsg;
6141 	struct nlmsghdr *nlh;
6142 	struct prefix_cacheinfo	ci;
6143 
6144 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
6145 	if (!nlh)
6146 		return -EMSGSIZE;
6147 
6148 	pmsg = nlmsg_data(nlh);
6149 	pmsg->prefix_family = AF_INET6;
6150 	pmsg->prefix_pad1 = 0;
6151 	pmsg->prefix_pad2 = 0;
6152 	pmsg->prefix_ifindex = idev->dev->ifindex;
6153 	pmsg->prefix_len = pinfo->prefix_len;
6154 	pmsg->prefix_type = pinfo->type;
6155 	pmsg->prefix_pad3 = 0;
6156 	pmsg->prefix_flags = pinfo->flags;
6157 
6158 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
6159 		goto nla_put_failure;
6160 	ci.preferred_time = ntohl(pinfo->prefered);
6161 	ci.valid_time = ntohl(pinfo->valid);
6162 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
6163 		goto nla_put_failure;
6164 	nlmsg_end(skb, nlh);
6165 	return 0;
6166 
6167 nla_put_failure:
6168 	nlmsg_cancel(skb, nlh);
6169 	return -EMSGSIZE;
6170 }
6171 
6172 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
6173 			 struct prefix_info *pinfo)
6174 {
6175 	struct sk_buff *skb;
6176 	struct net *net = dev_net(idev->dev);
6177 	int err = -ENOBUFS;
6178 
6179 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
6180 	if (!skb)
6181 		goto errout;
6182 
6183 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
6184 	if (err < 0) {
6185 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
6186 		WARN_ON(err == -EMSGSIZE);
6187 		kfree_skb(skb);
6188 		goto errout;
6189 	}
6190 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
6191 	return;
6192 errout:
6193 	if (err < 0)
6194 		rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
6195 }
6196 
6197 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6198 {
6199 	struct net *net = dev_net(ifp->idev->dev);
6200 
6201 	if (event)
6202 		ASSERT_RTNL();
6203 
6204 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
6205 
6206 	switch (event) {
6207 	case RTM_NEWADDR:
6208 		/*
6209 		 * If the address was optimistic we inserted the route at the
6210 		 * start of our DAD process, so we don't need to do it again.
6211 		 * If the device was taken down in the middle of the DAD
6212 		 * cycle there is a race where we could get here without a
6213 		 * host route, so nothing to insert. That will be fixed when
6214 		 * the device is brought up.
6215 		 */
6216 		if (ifp->rt && !rcu_access_pointer(ifp->rt->fib6_node)) {
6217 			ip6_ins_rt(net, ifp->rt);
6218 		} else if (!ifp->rt && (ifp->idev->dev->flags & IFF_UP)) {
6219 			pr_warn("BUG: Address %pI6c on device %s is missing its host route.\n",
6220 				&ifp->addr, ifp->idev->dev->name);
6221 		}
6222 
6223 		if (ifp->idev->cnf.forwarding)
6224 			addrconf_join_anycast(ifp);
6225 		if (!ipv6_addr_any(&ifp->peer_addr))
6226 			addrconf_prefix_route(&ifp->peer_addr, 128,
6227 					      ifp->rt_priority, ifp->idev->dev,
6228 					      0, 0, GFP_ATOMIC);
6229 		break;
6230 	case RTM_DELADDR:
6231 		if (ifp->idev->cnf.forwarding)
6232 			addrconf_leave_anycast(ifp);
6233 		addrconf_leave_solict(ifp->idev, &ifp->addr);
6234 		if (!ipv6_addr_any(&ifp->peer_addr)) {
6235 			struct fib6_info *rt;
6236 
6237 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
6238 						       ifp->idev->dev, 0, 0,
6239 						       false);
6240 			if (rt)
6241 				ip6_del_rt(net, rt, false);
6242 		}
6243 		if (ifp->rt) {
6244 			ip6_del_rt(net, ifp->rt, false);
6245 			ifp->rt = NULL;
6246 		}
6247 		rt_genid_bump_ipv6(net);
6248 		break;
6249 	}
6250 	atomic_inc(&net->ipv6.dev_addr_genid);
6251 }
6252 
6253 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6254 {
6255 	if (likely(ifp->idev->dead == 0))
6256 		__ipv6_ifa_notify(event, ifp);
6257 }
6258 
6259 #ifdef CONFIG_SYSCTL
6260 
6261 static int addrconf_sysctl_forward(struct ctl_table *ctl, int write,
6262 		void *buffer, size_t *lenp, loff_t *ppos)
6263 {
6264 	int *valp = ctl->data;
6265 	int val = *valp;
6266 	loff_t pos = *ppos;
6267 	struct ctl_table lctl;
6268 	int ret;
6269 
6270 	/*
6271 	 * ctl->data points to idev->cnf.forwarding, we should
6272 	 * not modify it until we get the rtnl lock.
6273 	 */
6274 	lctl = *ctl;
6275 	lctl.data = &val;
6276 
6277 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6278 
6279 	if (write)
6280 		ret = addrconf_fixup_forwarding(ctl, valp, val);
6281 	if (ret)
6282 		*ppos = pos;
6283 	return ret;
6284 }
6285 
6286 static int addrconf_sysctl_mtu(struct ctl_table *ctl, int write,
6287 		void *buffer, size_t *lenp, loff_t *ppos)
6288 {
6289 	struct inet6_dev *idev = ctl->extra1;
6290 	int min_mtu = IPV6_MIN_MTU;
6291 	struct ctl_table lctl;
6292 
6293 	lctl = *ctl;
6294 	lctl.extra1 = &min_mtu;
6295 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
6296 
6297 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
6298 }
6299 
6300 static void dev_disable_change(struct inet6_dev *idev)
6301 {
6302 	struct netdev_notifier_info info;
6303 
6304 	if (!idev || !idev->dev)
6305 		return;
6306 
6307 	netdev_notifier_info_init(&info, idev->dev);
6308 	if (idev->cnf.disable_ipv6)
6309 		addrconf_notify(NULL, NETDEV_DOWN, &info);
6310 	else
6311 		addrconf_notify(NULL, NETDEV_UP, &info);
6312 }
6313 
6314 static void addrconf_disable_change(struct net *net, __s32 newf)
6315 {
6316 	struct net_device *dev;
6317 	struct inet6_dev *idev;
6318 
6319 	for_each_netdev(net, dev) {
6320 		idev = __in6_dev_get(dev);
6321 		if (idev) {
6322 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
6323 			idev->cnf.disable_ipv6 = newf;
6324 			if (changed)
6325 				dev_disable_change(idev);
6326 		}
6327 	}
6328 }
6329 
6330 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)
6331 {
6332 	struct net *net;
6333 	int old;
6334 
6335 	if (!rtnl_trylock())
6336 		return restart_syscall();
6337 
6338 	net = (struct net *)table->extra2;
6339 	old = *p;
6340 	*p = newf;
6341 
6342 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
6343 		rtnl_unlock();
6344 		return 0;
6345 	}
6346 
6347 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
6348 		net->ipv6.devconf_dflt->disable_ipv6 = newf;
6349 		addrconf_disable_change(net, newf);
6350 	} else if ((!newf) ^ (!old))
6351 		dev_disable_change((struct inet6_dev *)table->extra1);
6352 
6353 	rtnl_unlock();
6354 	return 0;
6355 }
6356 
6357 static int addrconf_sysctl_disable(struct ctl_table *ctl, int write,
6358 		void *buffer, size_t *lenp, loff_t *ppos)
6359 {
6360 	int *valp = ctl->data;
6361 	int val = *valp;
6362 	loff_t pos = *ppos;
6363 	struct ctl_table lctl;
6364 	int ret;
6365 
6366 	/*
6367 	 * ctl->data points to idev->cnf.disable_ipv6, we should
6368 	 * not modify it until we get the rtnl lock.
6369 	 */
6370 	lctl = *ctl;
6371 	lctl.data = &val;
6372 
6373 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6374 
6375 	if (write)
6376 		ret = addrconf_disable_ipv6(ctl, valp, val);
6377 	if (ret)
6378 		*ppos = pos;
6379 	return ret;
6380 }
6381 
6382 static int addrconf_sysctl_proxy_ndp(struct ctl_table *ctl, int write,
6383 		void *buffer, size_t *lenp, loff_t *ppos)
6384 {
6385 	int *valp = ctl->data;
6386 	int ret;
6387 	int old, new;
6388 
6389 	old = *valp;
6390 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
6391 	new = *valp;
6392 
6393 	if (write && old != new) {
6394 		struct net *net = ctl->extra2;
6395 
6396 		if (!rtnl_trylock())
6397 			return restart_syscall();
6398 
6399 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
6400 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6401 						     NETCONFA_PROXY_NEIGH,
6402 						     NETCONFA_IFINDEX_DEFAULT,
6403 						     net->ipv6.devconf_dflt);
6404 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
6405 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6406 						     NETCONFA_PROXY_NEIGH,
6407 						     NETCONFA_IFINDEX_ALL,
6408 						     net->ipv6.devconf_all);
6409 		else {
6410 			struct inet6_dev *idev = ctl->extra1;
6411 
6412 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6413 						     NETCONFA_PROXY_NEIGH,
6414 						     idev->dev->ifindex,
6415 						     &idev->cnf);
6416 		}
6417 		rtnl_unlock();
6418 	}
6419 
6420 	return ret;
6421 }
6422 
6423 static int addrconf_sysctl_addr_gen_mode(struct ctl_table *ctl, int write,
6424 					 void *buffer, size_t *lenp,
6425 					 loff_t *ppos)
6426 {
6427 	int ret = 0;
6428 	u32 new_val;
6429 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
6430 	struct net *net = (struct net *)ctl->extra2;
6431 	struct ctl_table tmp = {
6432 		.data = &new_val,
6433 		.maxlen = sizeof(new_val),
6434 		.mode = ctl->mode,
6435 	};
6436 
6437 	if (!rtnl_trylock())
6438 		return restart_syscall();
6439 
6440 	new_val = *((u32 *)ctl->data);
6441 
6442 	ret = proc_douintvec(&tmp, write, buffer, lenp, ppos);
6443 	if (ret != 0)
6444 		goto out;
6445 
6446 	if (write) {
6447 		if (check_addr_gen_mode(new_val) < 0) {
6448 			ret = -EINVAL;
6449 			goto out;
6450 		}
6451 
6452 		if (idev) {
6453 			if (check_stable_privacy(idev, net, new_val) < 0) {
6454 				ret = -EINVAL;
6455 				goto out;
6456 			}
6457 
6458 			if (idev->cnf.addr_gen_mode != new_val) {
6459 				idev->cnf.addr_gen_mode = new_val;
6460 				addrconf_init_auto_addrs(idev->dev);
6461 			}
6462 		} else if (&net->ipv6.devconf_all->addr_gen_mode == ctl->data) {
6463 			struct net_device *dev;
6464 
6465 			net->ipv6.devconf_dflt->addr_gen_mode = new_val;
6466 			for_each_netdev(net, dev) {
6467 				idev = __in6_dev_get(dev);
6468 				if (idev &&
6469 				    idev->cnf.addr_gen_mode != new_val) {
6470 					idev->cnf.addr_gen_mode = new_val;
6471 					addrconf_init_auto_addrs(idev->dev);
6472 				}
6473 			}
6474 		}
6475 
6476 		*((u32 *)ctl->data) = new_val;
6477 	}
6478 
6479 out:
6480 	rtnl_unlock();
6481 
6482 	return ret;
6483 }
6484 
6485 static int addrconf_sysctl_stable_secret(struct ctl_table *ctl, int write,
6486 					 void *buffer, size_t *lenp,
6487 					 loff_t *ppos)
6488 {
6489 	int err;
6490 	struct in6_addr addr;
6491 	char str[IPV6_MAX_STRLEN];
6492 	struct ctl_table lctl = *ctl;
6493 	struct net *net = ctl->extra2;
6494 	struct ipv6_stable_secret *secret = ctl->data;
6495 
6496 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
6497 		return -EIO;
6498 
6499 	lctl.maxlen = IPV6_MAX_STRLEN;
6500 	lctl.data = str;
6501 
6502 	if (!rtnl_trylock())
6503 		return restart_syscall();
6504 
6505 	if (!write && !secret->initialized) {
6506 		err = -EIO;
6507 		goto out;
6508 	}
6509 
6510 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
6511 	if (err >= sizeof(str)) {
6512 		err = -EIO;
6513 		goto out;
6514 	}
6515 
6516 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
6517 	if (err || !write)
6518 		goto out;
6519 
6520 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
6521 		err = -EIO;
6522 		goto out;
6523 	}
6524 
6525 	secret->initialized = true;
6526 	secret->secret = addr;
6527 
6528 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
6529 		struct net_device *dev;
6530 
6531 		for_each_netdev(net, dev) {
6532 			struct inet6_dev *idev = __in6_dev_get(dev);
6533 
6534 			if (idev) {
6535 				idev->cnf.addr_gen_mode =
6536 					IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6537 			}
6538 		}
6539 	} else {
6540 		struct inet6_dev *idev = ctl->extra1;
6541 
6542 		idev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
6543 	}
6544 
6545 out:
6546 	rtnl_unlock();
6547 
6548 	return err;
6549 }
6550 
6551 static
6552 int addrconf_sysctl_ignore_routes_with_linkdown(struct ctl_table *ctl,
6553 						int write, void *buffer,
6554 						size_t *lenp,
6555 						loff_t *ppos)
6556 {
6557 	int *valp = ctl->data;
6558 	int val = *valp;
6559 	loff_t pos = *ppos;
6560 	struct ctl_table lctl;
6561 	int ret;
6562 
6563 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
6564 	 * we should not modify it until we get the rtnl lock.
6565 	 */
6566 	lctl = *ctl;
6567 	lctl.data = &val;
6568 
6569 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6570 
6571 	if (write)
6572 		ret = addrconf_fixup_linkdown(ctl, valp, val);
6573 	if (ret)
6574 		*ppos = pos;
6575 	return ret;
6576 }
6577 
6578 static
6579 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
6580 {
6581 	if (rt) {
6582 		if (action)
6583 			rt->dst.flags |= DST_NOPOLICY;
6584 		else
6585 			rt->dst.flags &= ~DST_NOPOLICY;
6586 	}
6587 }
6588 
6589 static
6590 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
6591 {
6592 	struct inet6_ifaddr *ifa;
6593 
6594 	read_lock_bh(&idev->lock);
6595 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
6596 		spin_lock(&ifa->lock);
6597 		if (ifa->rt) {
6598 			/* host routes only use builtin fib6_nh */
6599 			struct fib6_nh *nh = ifa->rt->fib6_nh;
6600 			int cpu;
6601 
6602 			rcu_read_lock();
6603 			ifa->rt->dst_nopolicy = val ? true : false;
6604 			if (nh->rt6i_pcpu) {
6605 				for_each_possible_cpu(cpu) {
6606 					struct rt6_info **rtp;
6607 
6608 					rtp = per_cpu_ptr(nh->rt6i_pcpu, cpu);
6609 					addrconf_set_nopolicy(*rtp, val);
6610 				}
6611 			}
6612 			rcu_read_unlock();
6613 		}
6614 		spin_unlock(&ifa->lock);
6615 	}
6616 	read_unlock_bh(&idev->lock);
6617 }
6618 
6619 static
6620 int addrconf_disable_policy(struct ctl_table *ctl, int *valp, int val)
6621 {
6622 	struct inet6_dev *idev;
6623 	struct net *net;
6624 
6625 	if (!rtnl_trylock())
6626 		return restart_syscall();
6627 
6628 	*valp = val;
6629 
6630 	net = (struct net *)ctl->extra2;
6631 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
6632 		rtnl_unlock();
6633 		return 0;
6634 	}
6635 
6636 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
6637 		struct net_device *dev;
6638 
6639 		for_each_netdev(net, dev) {
6640 			idev = __in6_dev_get(dev);
6641 			if (idev)
6642 				addrconf_disable_policy_idev(idev, val);
6643 		}
6644 	} else {
6645 		idev = (struct inet6_dev *)ctl->extra1;
6646 		addrconf_disable_policy_idev(idev, val);
6647 	}
6648 
6649 	rtnl_unlock();
6650 	return 0;
6651 }
6652 
6653 static int addrconf_sysctl_disable_policy(struct ctl_table *ctl, int write,
6654 				   void *buffer, size_t *lenp, loff_t *ppos)
6655 {
6656 	int *valp = ctl->data;
6657 	int val = *valp;
6658 	loff_t pos = *ppos;
6659 	struct ctl_table lctl;
6660 	int ret;
6661 
6662 	lctl = *ctl;
6663 	lctl.data = &val;
6664 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6665 
6666 	if (write && (*valp != val))
6667 		ret = addrconf_disable_policy(ctl, valp, val);
6668 
6669 	if (ret)
6670 		*ppos = pos;
6671 
6672 	return ret;
6673 }
6674 
6675 static int minus_one = -1;
6676 static const int two_five_five = 255;
6677 static u32 ioam6_if_id_max = U16_MAX;
6678 
6679 static const struct ctl_table addrconf_sysctl[] = {
6680 	{
6681 		.procname	= "forwarding",
6682 		.data		= &ipv6_devconf.forwarding,
6683 		.maxlen		= sizeof(int),
6684 		.mode		= 0644,
6685 		.proc_handler	= addrconf_sysctl_forward,
6686 	},
6687 	{
6688 		.procname	= "hop_limit",
6689 		.data		= &ipv6_devconf.hop_limit,
6690 		.maxlen		= sizeof(int),
6691 		.mode		= 0644,
6692 		.proc_handler	= proc_dointvec_minmax,
6693 		.extra1		= (void *)SYSCTL_ONE,
6694 		.extra2		= (void *)&two_five_five,
6695 	},
6696 	{
6697 		.procname	= "mtu",
6698 		.data		= &ipv6_devconf.mtu6,
6699 		.maxlen		= sizeof(int),
6700 		.mode		= 0644,
6701 		.proc_handler	= addrconf_sysctl_mtu,
6702 	},
6703 	{
6704 		.procname	= "accept_ra",
6705 		.data		= &ipv6_devconf.accept_ra,
6706 		.maxlen		= sizeof(int),
6707 		.mode		= 0644,
6708 		.proc_handler	= proc_dointvec,
6709 	},
6710 	{
6711 		.procname	= "accept_redirects",
6712 		.data		= &ipv6_devconf.accept_redirects,
6713 		.maxlen		= sizeof(int),
6714 		.mode		= 0644,
6715 		.proc_handler	= proc_dointvec,
6716 	},
6717 	{
6718 		.procname	= "autoconf",
6719 		.data		= &ipv6_devconf.autoconf,
6720 		.maxlen		= sizeof(int),
6721 		.mode		= 0644,
6722 		.proc_handler	= proc_dointvec,
6723 	},
6724 	{
6725 		.procname	= "dad_transmits",
6726 		.data		= &ipv6_devconf.dad_transmits,
6727 		.maxlen		= sizeof(int),
6728 		.mode		= 0644,
6729 		.proc_handler	= proc_dointvec,
6730 	},
6731 	{
6732 		.procname	= "router_solicitations",
6733 		.data		= &ipv6_devconf.rtr_solicits,
6734 		.maxlen		= sizeof(int),
6735 		.mode		= 0644,
6736 		.proc_handler	= proc_dointvec_minmax,
6737 		.extra1		= &minus_one,
6738 	},
6739 	{
6740 		.procname	= "router_solicitation_interval",
6741 		.data		= &ipv6_devconf.rtr_solicit_interval,
6742 		.maxlen		= sizeof(int),
6743 		.mode		= 0644,
6744 		.proc_handler	= proc_dointvec_jiffies,
6745 	},
6746 	{
6747 		.procname	= "router_solicitation_max_interval",
6748 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6749 		.maxlen		= sizeof(int),
6750 		.mode		= 0644,
6751 		.proc_handler	= proc_dointvec_jiffies,
6752 	},
6753 	{
6754 		.procname	= "router_solicitation_delay",
6755 		.data		= &ipv6_devconf.rtr_solicit_delay,
6756 		.maxlen		= sizeof(int),
6757 		.mode		= 0644,
6758 		.proc_handler	= proc_dointvec_jiffies,
6759 	},
6760 	{
6761 		.procname	= "force_mld_version",
6762 		.data		= &ipv6_devconf.force_mld_version,
6763 		.maxlen		= sizeof(int),
6764 		.mode		= 0644,
6765 		.proc_handler	= proc_dointvec,
6766 	},
6767 	{
6768 		.procname	= "mldv1_unsolicited_report_interval",
6769 		.data		=
6770 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6771 		.maxlen		= sizeof(int),
6772 		.mode		= 0644,
6773 		.proc_handler	= proc_dointvec_ms_jiffies,
6774 	},
6775 	{
6776 		.procname	= "mldv2_unsolicited_report_interval",
6777 		.data		=
6778 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6779 		.maxlen		= sizeof(int),
6780 		.mode		= 0644,
6781 		.proc_handler	= proc_dointvec_ms_jiffies,
6782 	},
6783 	{
6784 		.procname	= "use_tempaddr",
6785 		.data		= &ipv6_devconf.use_tempaddr,
6786 		.maxlen		= sizeof(int),
6787 		.mode		= 0644,
6788 		.proc_handler	= proc_dointvec,
6789 	},
6790 	{
6791 		.procname	= "temp_valid_lft",
6792 		.data		= &ipv6_devconf.temp_valid_lft,
6793 		.maxlen		= sizeof(int),
6794 		.mode		= 0644,
6795 		.proc_handler	= proc_dointvec,
6796 	},
6797 	{
6798 		.procname	= "temp_prefered_lft",
6799 		.data		= &ipv6_devconf.temp_prefered_lft,
6800 		.maxlen		= sizeof(int),
6801 		.mode		= 0644,
6802 		.proc_handler	= proc_dointvec,
6803 	},
6804 	{
6805 		.procname	= "regen_max_retry",
6806 		.data		= &ipv6_devconf.regen_max_retry,
6807 		.maxlen		= sizeof(int),
6808 		.mode		= 0644,
6809 		.proc_handler	= proc_dointvec,
6810 	},
6811 	{
6812 		.procname	= "max_desync_factor",
6813 		.data		= &ipv6_devconf.max_desync_factor,
6814 		.maxlen		= sizeof(int),
6815 		.mode		= 0644,
6816 		.proc_handler	= proc_dointvec,
6817 	},
6818 	{
6819 		.procname	= "max_addresses",
6820 		.data		= &ipv6_devconf.max_addresses,
6821 		.maxlen		= sizeof(int),
6822 		.mode		= 0644,
6823 		.proc_handler	= proc_dointvec,
6824 	},
6825 	{
6826 		.procname	= "accept_ra_defrtr",
6827 		.data		= &ipv6_devconf.accept_ra_defrtr,
6828 		.maxlen		= sizeof(int),
6829 		.mode		= 0644,
6830 		.proc_handler	= proc_dointvec,
6831 	},
6832 	{
6833 		.procname	= "ra_defrtr_metric",
6834 		.data		= &ipv6_devconf.ra_defrtr_metric,
6835 		.maxlen		= sizeof(u32),
6836 		.mode		= 0644,
6837 		.proc_handler	= proc_douintvec_minmax,
6838 		.extra1		= (void *)SYSCTL_ONE,
6839 	},
6840 	{
6841 		.procname	= "accept_ra_min_hop_limit",
6842 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6843 		.maxlen		= sizeof(int),
6844 		.mode		= 0644,
6845 		.proc_handler	= proc_dointvec,
6846 	},
6847 	{
6848 		.procname	= "accept_ra_min_lft",
6849 		.data		= &ipv6_devconf.accept_ra_min_lft,
6850 		.maxlen		= sizeof(int),
6851 		.mode		= 0644,
6852 		.proc_handler	= proc_dointvec,
6853 	},
6854 	{
6855 		.procname	= "accept_ra_pinfo",
6856 		.data		= &ipv6_devconf.accept_ra_pinfo,
6857 		.maxlen		= sizeof(int),
6858 		.mode		= 0644,
6859 		.proc_handler	= proc_dointvec,
6860 	},
6861 #ifdef CONFIG_IPV6_ROUTER_PREF
6862 	{
6863 		.procname	= "accept_ra_rtr_pref",
6864 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6865 		.maxlen		= sizeof(int),
6866 		.mode		= 0644,
6867 		.proc_handler	= proc_dointvec,
6868 	},
6869 	{
6870 		.procname	= "router_probe_interval",
6871 		.data		= &ipv6_devconf.rtr_probe_interval,
6872 		.maxlen		= sizeof(int),
6873 		.mode		= 0644,
6874 		.proc_handler	= proc_dointvec_jiffies,
6875 	},
6876 #ifdef CONFIG_IPV6_ROUTE_INFO
6877 	{
6878 		.procname	= "accept_ra_rt_info_min_plen",
6879 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6880 		.maxlen		= sizeof(int),
6881 		.mode		= 0644,
6882 		.proc_handler	= proc_dointvec,
6883 	},
6884 	{
6885 		.procname	= "accept_ra_rt_info_max_plen",
6886 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6887 		.maxlen		= sizeof(int),
6888 		.mode		= 0644,
6889 		.proc_handler	= proc_dointvec,
6890 	},
6891 #endif
6892 #endif
6893 	{
6894 		.procname	= "proxy_ndp",
6895 		.data		= &ipv6_devconf.proxy_ndp,
6896 		.maxlen		= sizeof(int),
6897 		.mode		= 0644,
6898 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6899 	},
6900 	{
6901 		.procname	= "accept_source_route",
6902 		.data		= &ipv6_devconf.accept_source_route,
6903 		.maxlen		= sizeof(int),
6904 		.mode		= 0644,
6905 		.proc_handler	= proc_dointvec,
6906 	},
6907 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
6908 	{
6909 		.procname	= "optimistic_dad",
6910 		.data		= &ipv6_devconf.optimistic_dad,
6911 		.maxlen		= sizeof(int),
6912 		.mode		= 0644,
6913 		.proc_handler   = proc_dointvec,
6914 	},
6915 	{
6916 		.procname	= "use_optimistic",
6917 		.data		= &ipv6_devconf.use_optimistic,
6918 		.maxlen		= sizeof(int),
6919 		.mode		= 0644,
6920 		.proc_handler	= proc_dointvec,
6921 	},
6922 #endif
6923 #ifdef CONFIG_IPV6_MROUTE
6924 	{
6925 		.procname	= "mc_forwarding",
6926 		.data		= &ipv6_devconf.mc_forwarding,
6927 		.maxlen		= sizeof(int),
6928 		.mode		= 0444,
6929 		.proc_handler	= proc_dointvec,
6930 	},
6931 #endif
6932 	{
6933 		.procname	= "disable_ipv6",
6934 		.data		= &ipv6_devconf.disable_ipv6,
6935 		.maxlen		= sizeof(int),
6936 		.mode		= 0644,
6937 		.proc_handler	= addrconf_sysctl_disable,
6938 	},
6939 	{
6940 		.procname	= "accept_dad",
6941 		.data		= &ipv6_devconf.accept_dad,
6942 		.maxlen		= sizeof(int),
6943 		.mode		= 0644,
6944 		.proc_handler	= proc_dointvec,
6945 	},
6946 	{
6947 		.procname	= "force_tllao",
6948 		.data		= &ipv6_devconf.force_tllao,
6949 		.maxlen		= sizeof(int),
6950 		.mode		= 0644,
6951 		.proc_handler	= proc_dointvec
6952 	},
6953 	{
6954 		.procname	= "ndisc_notify",
6955 		.data		= &ipv6_devconf.ndisc_notify,
6956 		.maxlen		= sizeof(int),
6957 		.mode		= 0644,
6958 		.proc_handler	= proc_dointvec
6959 	},
6960 	{
6961 		.procname	= "suppress_frag_ndisc",
6962 		.data		= &ipv6_devconf.suppress_frag_ndisc,
6963 		.maxlen		= sizeof(int),
6964 		.mode		= 0644,
6965 		.proc_handler	= proc_dointvec
6966 	},
6967 	{
6968 		.procname	= "accept_ra_from_local",
6969 		.data		= &ipv6_devconf.accept_ra_from_local,
6970 		.maxlen		= sizeof(int),
6971 		.mode		= 0644,
6972 		.proc_handler	= proc_dointvec,
6973 	},
6974 	{
6975 		.procname	= "accept_ra_mtu",
6976 		.data		= &ipv6_devconf.accept_ra_mtu,
6977 		.maxlen		= sizeof(int),
6978 		.mode		= 0644,
6979 		.proc_handler	= proc_dointvec,
6980 	},
6981 	{
6982 		.procname	= "stable_secret",
6983 		.data		= &ipv6_devconf.stable_secret,
6984 		.maxlen		= IPV6_MAX_STRLEN,
6985 		.mode		= 0600,
6986 		.proc_handler	= addrconf_sysctl_stable_secret,
6987 	},
6988 	{
6989 		.procname	= "use_oif_addrs_only",
6990 		.data		= &ipv6_devconf.use_oif_addrs_only,
6991 		.maxlen		= sizeof(int),
6992 		.mode		= 0644,
6993 		.proc_handler	= proc_dointvec,
6994 	},
6995 	{
6996 		.procname	= "ignore_routes_with_linkdown",
6997 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
6998 		.maxlen		= sizeof(int),
6999 		.mode		= 0644,
7000 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
7001 	},
7002 	{
7003 		.procname	= "drop_unicast_in_l2_multicast",
7004 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
7005 		.maxlen		= sizeof(int),
7006 		.mode		= 0644,
7007 		.proc_handler	= proc_dointvec,
7008 	},
7009 	{
7010 		.procname	= "drop_unsolicited_na",
7011 		.data		= &ipv6_devconf.drop_unsolicited_na,
7012 		.maxlen		= sizeof(int),
7013 		.mode		= 0644,
7014 		.proc_handler	= proc_dointvec,
7015 	},
7016 	{
7017 		.procname	= "keep_addr_on_down",
7018 		.data		= &ipv6_devconf.keep_addr_on_down,
7019 		.maxlen		= sizeof(int),
7020 		.mode		= 0644,
7021 		.proc_handler	= proc_dointvec,
7022 
7023 	},
7024 	{
7025 		.procname	= "seg6_enabled",
7026 		.data		= &ipv6_devconf.seg6_enabled,
7027 		.maxlen		= sizeof(int),
7028 		.mode		= 0644,
7029 		.proc_handler	= proc_dointvec,
7030 	},
7031 #ifdef CONFIG_IPV6_SEG6_HMAC
7032 	{
7033 		.procname	= "seg6_require_hmac",
7034 		.data		= &ipv6_devconf.seg6_require_hmac,
7035 		.maxlen		= sizeof(int),
7036 		.mode		= 0644,
7037 		.proc_handler	= proc_dointvec,
7038 	},
7039 #endif
7040 	{
7041 		.procname       = "enhanced_dad",
7042 		.data           = &ipv6_devconf.enhanced_dad,
7043 		.maxlen         = sizeof(int),
7044 		.mode           = 0644,
7045 		.proc_handler   = proc_dointvec,
7046 	},
7047 	{
7048 		.procname	= "addr_gen_mode",
7049 		.data		= &ipv6_devconf.addr_gen_mode,
7050 		.maxlen		= sizeof(int),
7051 		.mode		= 0644,
7052 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
7053 	},
7054 	{
7055 		.procname       = "disable_policy",
7056 		.data           = &ipv6_devconf.disable_policy,
7057 		.maxlen         = sizeof(int),
7058 		.mode           = 0644,
7059 		.proc_handler   = addrconf_sysctl_disable_policy,
7060 	},
7061 	{
7062 		.procname	= "ndisc_tclass",
7063 		.data		= &ipv6_devconf.ndisc_tclass,
7064 		.maxlen		= sizeof(int),
7065 		.mode		= 0644,
7066 		.proc_handler	= proc_dointvec_minmax,
7067 		.extra1		= (void *)SYSCTL_ZERO,
7068 		.extra2		= (void *)&two_five_five,
7069 	},
7070 	{
7071 		.procname	= "rpl_seg_enabled",
7072 		.data		= &ipv6_devconf.rpl_seg_enabled,
7073 		.maxlen		= sizeof(int),
7074 		.mode		= 0644,
7075 		.proc_handler	= proc_dointvec,
7076 	},
7077 	{
7078 		.procname	= "ioam6_enabled",
7079 		.data		= &ipv6_devconf.ioam6_enabled,
7080 		.maxlen		= sizeof(u8),
7081 		.mode		= 0644,
7082 		.proc_handler	= proc_dou8vec_minmax,
7083 		.extra1		= (void *)SYSCTL_ZERO,
7084 		.extra2		= (void *)SYSCTL_ONE,
7085 	},
7086 	{
7087 		.procname	= "ioam6_id",
7088 		.data		= &ipv6_devconf.ioam6_id,
7089 		.maxlen		= sizeof(u32),
7090 		.mode		= 0644,
7091 		.proc_handler	= proc_douintvec_minmax,
7092 		.extra1		= (void *)SYSCTL_ZERO,
7093 		.extra2		= (void *)&ioam6_if_id_max,
7094 	},
7095 	{
7096 		.procname	= "ioam6_id_wide",
7097 		.data		= &ipv6_devconf.ioam6_id_wide,
7098 		.maxlen		= sizeof(u32),
7099 		.mode		= 0644,
7100 		.proc_handler	= proc_douintvec,
7101 	},
7102 	{
7103 		.procname	= "ndisc_evict_nocarrier",
7104 		.data		= &ipv6_devconf.ndisc_evict_nocarrier,
7105 		.maxlen		= sizeof(u8),
7106 		.mode		= 0644,
7107 		.proc_handler	= proc_dou8vec_minmax,
7108 		.extra1		= (void *)SYSCTL_ZERO,
7109 		.extra2		= (void *)SYSCTL_ONE,
7110 	},
7111 	{
7112 		.procname	= "accept_untracked_na",
7113 		.data		= &ipv6_devconf.accept_untracked_na,
7114 		.maxlen		= sizeof(int),
7115 		.mode		= 0644,
7116 		.proc_handler	= proc_dointvec_minmax,
7117 		.extra1		= SYSCTL_ZERO,
7118 		.extra2		= SYSCTL_TWO,
7119 	},
7120 	{
7121 		/* sentinel */
7122 	}
7123 };
7124 
7125 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
7126 		struct inet6_dev *idev, struct ipv6_devconf *p)
7127 {
7128 	int i, ifindex;
7129 	struct ctl_table *table;
7130 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
7131 
7132 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL_ACCOUNT);
7133 	if (!table)
7134 		goto out;
7135 
7136 	for (i = 0; table[i].data; i++) {
7137 		table[i].data += (char *)p - (char *)&ipv6_devconf;
7138 		/* If one of these is already set, then it is not safe to
7139 		 * overwrite either of them: this makes proc_dointvec_minmax
7140 		 * usable.
7141 		 */
7142 		if (!table[i].extra1 && !table[i].extra2) {
7143 			table[i].extra1 = idev; /* embedded; no ref */
7144 			table[i].extra2 = net;
7145 		}
7146 	}
7147 
7148 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
7149 
7150 	p->sysctl_header = register_net_sysctl_sz(net, path, table,
7151 						  ARRAY_SIZE(addrconf_sysctl));
7152 	if (!p->sysctl_header)
7153 		goto free;
7154 
7155 	if (!strcmp(dev_name, "all"))
7156 		ifindex = NETCONFA_IFINDEX_ALL;
7157 	else if (!strcmp(dev_name, "default"))
7158 		ifindex = NETCONFA_IFINDEX_DEFAULT;
7159 	else
7160 		ifindex = idev->dev->ifindex;
7161 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
7162 				     ifindex, p);
7163 	return 0;
7164 
7165 free:
7166 	kfree(table);
7167 out:
7168 	return -ENOBUFS;
7169 }
7170 
7171 static void __addrconf_sysctl_unregister(struct net *net,
7172 					 struct ipv6_devconf *p, int ifindex)
7173 {
7174 	struct ctl_table *table;
7175 
7176 	if (!p->sysctl_header)
7177 		return;
7178 
7179 	table = p->sysctl_header->ctl_table_arg;
7180 	unregister_net_sysctl_table(p->sysctl_header);
7181 	p->sysctl_header = NULL;
7182 	kfree(table);
7183 
7184 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
7185 }
7186 
7187 static int addrconf_sysctl_register(struct inet6_dev *idev)
7188 {
7189 	int err;
7190 
7191 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
7192 		return -EINVAL;
7193 
7194 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
7195 				    &ndisc_ifinfo_sysctl_change);
7196 	if (err)
7197 		return err;
7198 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
7199 					 idev, &idev->cnf);
7200 	if (err)
7201 		neigh_sysctl_unregister(idev->nd_parms);
7202 
7203 	return err;
7204 }
7205 
7206 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
7207 {
7208 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
7209 				     idev->dev->ifindex);
7210 	neigh_sysctl_unregister(idev->nd_parms);
7211 }
7212 
7213 
7214 #endif
7215 
7216 static int __net_init addrconf_init_net(struct net *net)
7217 {
7218 	int err = -ENOMEM;
7219 	struct ipv6_devconf *all, *dflt;
7220 
7221 	spin_lock_init(&net->ipv6.addrconf_hash_lock);
7222 	INIT_DEFERRABLE_WORK(&net->ipv6.addr_chk_work, addrconf_verify_work);
7223 	net->ipv6.inet6_addr_lst = kcalloc(IN6_ADDR_HSIZE,
7224 					   sizeof(struct hlist_head),
7225 					   GFP_KERNEL);
7226 	if (!net->ipv6.inet6_addr_lst)
7227 		goto err_alloc_addr;
7228 
7229 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
7230 	if (!all)
7231 		goto err_alloc_all;
7232 
7233 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
7234 	if (!dflt)
7235 		goto err_alloc_dflt;
7236 
7237 	if (!net_eq(net, &init_net)) {
7238 		switch (net_inherit_devconf()) {
7239 		case 1:  /* copy from init_net */
7240 			memcpy(all, init_net.ipv6.devconf_all,
7241 			       sizeof(ipv6_devconf));
7242 			memcpy(dflt, init_net.ipv6.devconf_dflt,
7243 			       sizeof(ipv6_devconf_dflt));
7244 			break;
7245 		case 3: /* copy from the current netns */
7246 			memcpy(all, current->nsproxy->net_ns->ipv6.devconf_all,
7247 			       sizeof(ipv6_devconf));
7248 			memcpy(dflt,
7249 			       current->nsproxy->net_ns->ipv6.devconf_dflt,
7250 			       sizeof(ipv6_devconf_dflt));
7251 			break;
7252 		case 0:
7253 		case 2:
7254 			/* use compiled values */
7255 			break;
7256 		}
7257 	}
7258 
7259 	/* these will be inherited by all namespaces */
7260 	dflt->autoconf = ipv6_defaults.autoconf;
7261 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
7262 
7263 	dflt->stable_secret.initialized = false;
7264 	all->stable_secret.initialized = false;
7265 
7266 	net->ipv6.devconf_all = all;
7267 	net->ipv6.devconf_dflt = dflt;
7268 
7269 #ifdef CONFIG_SYSCTL
7270 	err = __addrconf_sysctl_register(net, "all", NULL, all);
7271 	if (err < 0)
7272 		goto err_reg_all;
7273 
7274 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
7275 	if (err < 0)
7276 		goto err_reg_dflt;
7277 #endif
7278 	return 0;
7279 
7280 #ifdef CONFIG_SYSCTL
7281 err_reg_dflt:
7282 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
7283 err_reg_all:
7284 	kfree(dflt);
7285 	net->ipv6.devconf_dflt = NULL;
7286 #endif
7287 err_alloc_dflt:
7288 	kfree(all);
7289 	net->ipv6.devconf_all = NULL;
7290 err_alloc_all:
7291 	kfree(net->ipv6.inet6_addr_lst);
7292 err_alloc_addr:
7293 	return err;
7294 }
7295 
7296 static void __net_exit addrconf_exit_net(struct net *net)
7297 {
7298 	int i;
7299 
7300 #ifdef CONFIG_SYSCTL
7301 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
7302 				     NETCONFA_IFINDEX_DEFAULT);
7303 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
7304 				     NETCONFA_IFINDEX_ALL);
7305 #endif
7306 	kfree(net->ipv6.devconf_dflt);
7307 	net->ipv6.devconf_dflt = NULL;
7308 	kfree(net->ipv6.devconf_all);
7309 	net->ipv6.devconf_all = NULL;
7310 
7311 	cancel_delayed_work_sync(&net->ipv6.addr_chk_work);
7312 	/*
7313 	 *	Check hash table, then free it.
7314 	 */
7315 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7316 		WARN_ON_ONCE(!hlist_empty(&net->ipv6.inet6_addr_lst[i]));
7317 
7318 	kfree(net->ipv6.inet6_addr_lst);
7319 	net->ipv6.inet6_addr_lst = NULL;
7320 }
7321 
7322 static struct pernet_operations addrconf_ops = {
7323 	.init = addrconf_init_net,
7324 	.exit = addrconf_exit_net,
7325 };
7326 
7327 static struct rtnl_af_ops inet6_ops __read_mostly = {
7328 	.family		  = AF_INET6,
7329 	.fill_link_af	  = inet6_fill_link_af,
7330 	.get_link_af_size = inet6_get_link_af_size,
7331 	.validate_link_af = inet6_validate_link_af,
7332 	.set_link_af	  = inet6_set_link_af,
7333 };
7334 
7335 /*
7336  *	Init / cleanup code
7337  */
7338 
7339 int __init addrconf_init(void)
7340 {
7341 	struct inet6_dev *idev;
7342 	int err;
7343 
7344 	err = ipv6_addr_label_init();
7345 	if (err < 0) {
7346 		pr_crit("%s: cannot initialize default policy table: %d\n",
7347 			__func__, err);
7348 		goto out;
7349 	}
7350 
7351 	err = register_pernet_subsys(&addrconf_ops);
7352 	if (err < 0)
7353 		goto out_addrlabel;
7354 
7355 	addrconf_wq = create_workqueue("ipv6_addrconf");
7356 	if (!addrconf_wq) {
7357 		err = -ENOMEM;
7358 		goto out_nowq;
7359 	}
7360 
7361 	rtnl_lock();
7362 	idev = ipv6_add_dev(blackhole_netdev);
7363 	rtnl_unlock();
7364 	if (IS_ERR(idev)) {
7365 		err = PTR_ERR(idev);
7366 		goto errlo;
7367 	}
7368 
7369 	ip6_route_init_special_entries();
7370 
7371 	register_netdevice_notifier(&ipv6_dev_notf);
7372 
7373 	addrconf_verify(&init_net);
7374 
7375 	rtnl_af_register(&inet6_ops);
7376 
7377 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETLINK,
7378 				   NULL, inet6_dump_ifinfo, 0);
7379 	if (err < 0)
7380 		goto errout;
7381 
7382 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWADDR,
7383 				   inet6_rtm_newaddr, NULL, 0);
7384 	if (err < 0)
7385 		goto errout;
7386 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELADDR,
7387 				   inet6_rtm_deladdr, NULL, 0);
7388 	if (err < 0)
7389 		goto errout;
7390 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDR,
7391 				   inet6_rtm_getaddr, inet6_dump_ifaddr,
7392 				   RTNL_FLAG_DOIT_UNLOCKED);
7393 	if (err < 0)
7394 		goto errout;
7395 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETMULTICAST,
7396 				   NULL, inet6_dump_ifmcaddr, 0);
7397 	if (err < 0)
7398 		goto errout;
7399 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETANYCAST,
7400 				   NULL, inet6_dump_ifacaddr, 0);
7401 	if (err < 0)
7402 		goto errout;
7403 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETNETCONF,
7404 				   inet6_netconf_get_devconf,
7405 				   inet6_netconf_dump_devconf,
7406 				   RTNL_FLAG_DOIT_UNLOCKED);
7407 	if (err < 0)
7408 		goto errout;
7409 	err = ipv6_addr_label_rtnl_register();
7410 	if (err < 0)
7411 		goto errout;
7412 
7413 	return 0;
7414 errout:
7415 	rtnl_unregister_all(PF_INET6);
7416 	rtnl_af_unregister(&inet6_ops);
7417 	unregister_netdevice_notifier(&ipv6_dev_notf);
7418 errlo:
7419 	destroy_workqueue(addrconf_wq);
7420 out_nowq:
7421 	unregister_pernet_subsys(&addrconf_ops);
7422 out_addrlabel:
7423 	ipv6_addr_label_cleanup();
7424 out:
7425 	return err;
7426 }
7427 
7428 void addrconf_cleanup(void)
7429 {
7430 	struct net_device *dev;
7431 
7432 	unregister_netdevice_notifier(&ipv6_dev_notf);
7433 	unregister_pernet_subsys(&addrconf_ops);
7434 	ipv6_addr_label_cleanup();
7435 
7436 	rtnl_af_unregister(&inet6_ops);
7437 
7438 	rtnl_lock();
7439 
7440 	/* clean dev list */
7441 	for_each_netdev(&init_net, dev) {
7442 		if (__in6_dev_get(dev) == NULL)
7443 			continue;
7444 		addrconf_ifdown(dev, true);
7445 	}
7446 	addrconf_ifdown(init_net.loopback_dev, true);
7447 
7448 	rtnl_unlock();
7449 
7450 	destroy_workqueue(addrconf_wq);
7451 }
7452