xref: /linux/net/ipv6/addrconf.c (revision 9410645520e9b820069761f3450ef6661418e279)
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/ip_tunnels.h>
67 #include <net/net_namespace.h>
68 #include <net/sock.h>
69 #include <net/snmp.h>
70 
71 #include <net/6lowpan.h>
72 #include <net/firewire.h>
73 #include <net/ipv6.h>
74 #include <net/protocol.h>
75 #include <net/ndisc.h>
76 #include <net/ip6_route.h>
77 #include <net/addrconf.h>
78 #include <net/tcp.h>
79 #include <net/ip.h>
80 #include <net/netlink.h>
81 #include <net/pkt_sched.h>
82 #include <net/l3mdev.h>
83 #include <linux/if_tunnel.h>
84 #include <linux/rtnetlink.h>
85 #include <linux/netconf.h>
86 #include <linux/random.h>
87 #include <linux/uaccess.h>
88 #include <asm/unaligned.h>
89 
90 #include <linux/proc_fs.h>
91 #include <linux/seq_file.h>
92 #include <linux/export.h>
93 #include <linux/ioam6.h>
94 
95 #define IPV6_MAX_STRLEN \
96 	sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")
97 
98 static inline u32 cstamp_delta(unsigned long cstamp)
99 {
100 	return (cstamp - INITIAL_JIFFIES) * 100UL / HZ;
101 }
102 
103 static inline s32 rfc3315_s14_backoff_init(s32 irt)
104 {
105 	/* multiply 'initial retransmission time' by 0.9 .. 1.1 */
106 	u64 tmp = get_random_u32_inclusive(900000, 1100000) * (u64)irt;
107 	do_div(tmp, 1000000);
108 	return (s32)tmp;
109 }
110 
111 static inline s32 rfc3315_s14_backoff_update(s32 rt, s32 mrt)
112 {
113 	/* multiply 'retransmission timeout' by 1.9 .. 2.1 */
114 	u64 tmp = get_random_u32_inclusive(1900000, 2100000) * (u64)rt;
115 	do_div(tmp, 1000000);
116 	if ((s32)tmp > mrt) {
117 		/* multiply 'maximum retransmission time' by 0.9 .. 1.1 */
118 		tmp = get_random_u32_inclusive(900000, 1100000) * (u64)mrt;
119 		do_div(tmp, 1000000);
120 	}
121 	return (s32)tmp;
122 }
123 
124 #ifdef CONFIG_SYSCTL
125 static int addrconf_sysctl_register(struct inet6_dev *idev);
126 static void addrconf_sysctl_unregister(struct inet6_dev *idev);
127 #else
128 static inline int addrconf_sysctl_register(struct inet6_dev *idev)
129 {
130 	return 0;
131 }
132 
133 static inline void addrconf_sysctl_unregister(struct inet6_dev *idev)
134 {
135 }
136 #endif
137 
138 static void ipv6_gen_rnd_iid(struct in6_addr *addr);
139 
140 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev);
141 static int ipv6_count_addresses(const struct inet6_dev *idev);
142 static int ipv6_generate_stable_address(struct in6_addr *addr,
143 					u8 dad_count,
144 					const struct inet6_dev *idev);
145 
146 #define IN6_ADDR_HSIZE_SHIFT	8
147 #define IN6_ADDR_HSIZE		(1 << IN6_ADDR_HSIZE_SHIFT)
148 
149 static void addrconf_verify(struct net *net);
150 static void addrconf_verify_rtnl(struct net *net);
151 
152 static struct workqueue_struct *addrconf_wq;
153 
154 static void addrconf_join_anycast(struct inet6_ifaddr *ifp);
155 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp);
156 
157 static void addrconf_type_change(struct net_device *dev,
158 				 unsigned long event);
159 static int addrconf_ifdown(struct net_device *dev, bool unregister);
160 
161 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
162 						  int plen,
163 						  const struct net_device *dev,
164 						  u32 flags, u32 noflags,
165 						  bool no_gw);
166 
167 static void addrconf_dad_start(struct inet6_ifaddr *ifp);
168 static void addrconf_dad_work(struct work_struct *w);
169 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
170 				   bool send_na);
171 static void addrconf_dad_run(struct inet6_dev *idev, bool restart);
172 static void addrconf_rs_timer(struct timer_list *t);
173 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
174 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifa);
175 
176 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
177 				struct prefix_info *pinfo);
178 
179 static struct ipv6_devconf ipv6_devconf __read_mostly = {
180 	.forwarding		= 0,
181 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
182 	.mtu6			= IPV6_MIN_MTU,
183 	.accept_ra		= 1,
184 	.accept_redirects	= 1,
185 	.autoconf		= 1,
186 	.force_mld_version	= 0,
187 	.mldv1_unsolicited_report_interval = 10 * HZ,
188 	.mldv2_unsolicited_report_interval = HZ,
189 	.dad_transmits		= 1,
190 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
191 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
192 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
193 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
194 	.use_tempaddr		= 0,
195 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
196 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
197 	.regen_min_advance	= REGEN_MIN_ADVANCE,
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 	.ra_honor_pio_life	= 0,
240 	.ra_honor_pio_pflag	= 0,
241 };
242 
243 static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
244 	.forwarding		= 0,
245 	.hop_limit		= IPV6_DEFAULT_HOPLIMIT,
246 	.mtu6			= IPV6_MIN_MTU,
247 	.accept_ra		= 1,
248 	.accept_redirects	= 1,
249 	.autoconf		= 1,
250 	.force_mld_version	= 0,
251 	.mldv1_unsolicited_report_interval = 10 * HZ,
252 	.mldv2_unsolicited_report_interval = HZ,
253 	.dad_transmits		= 1,
254 	.rtr_solicits		= MAX_RTR_SOLICITATIONS,
255 	.rtr_solicit_interval	= RTR_SOLICITATION_INTERVAL,
256 	.rtr_solicit_max_interval = RTR_SOLICITATION_MAX_INTERVAL,
257 	.rtr_solicit_delay	= MAX_RTR_SOLICITATION_DELAY,
258 	.use_tempaddr		= 0,
259 	.temp_valid_lft		= TEMP_VALID_LIFETIME,
260 	.temp_prefered_lft	= TEMP_PREFERRED_LIFETIME,
261 	.regen_min_advance	= REGEN_MIN_ADVANCE,
262 	.regen_max_retry	= REGEN_MAX_RETRY,
263 	.max_desync_factor	= MAX_DESYNC_FACTOR,
264 	.max_addresses		= IPV6_MAX_ADDRESSES,
265 	.accept_ra_defrtr	= 1,
266 	.ra_defrtr_metric	= IP6_RT_PRIO_USER,
267 	.accept_ra_from_local	= 0,
268 	.accept_ra_min_hop_limit= 1,
269 	.accept_ra_min_lft	= 0,
270 	.accept_ra_pinfo	= 1,
271 #ifdef CONFIG_IPV6_ROUTER_PREF
272 	.accept_ra_rtr_pref	= 1,
273 	.rtr_probe_interval	= 60 * HZ,
274 #ifdef CONFIG_IPV6_ROUTE_INFO
275 	.accept_ra_rt_info_min_plen = 0,
276 	.accept_ra_rt_info_max_plen = 0,
277 #endif
278 #endif
279 	.proxy_ndp		= 0,
280 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
281 	.disable_ipv6		= 0,
282 	.accept_dad		= 1,
283 	.suppress_frag_ndisc	= 1,
284 	.accept_ra_mtu		= 1,
285 	.stable_secret		= {
286 		.initialized = false,
287 	},
288 	.use_oif_addrs_only	= 0,
289 	.ignore_routes_with_linkdown = 0,
290 	.keep_addr_on_down	= 0,
291 	.seg6_enabled		= 0,
292 #ifdef CONFIG_IPV6_SEG6_HMAC
293 	.seg6_require_hmac	= 0,
294 #endif
295 	.enhanced_dad           = 1,
296 	.addr_gen_mode		= IN6_ADDR_GEN_MODE_EUI64,
297 	.disable_policy		= 0,
298 	.rpl_seg_enabled	= 0,
299 	.ioam6_enabled		= 0,
300 	.ioam6_id               = IOAM6_DEFAULT_IF_ID,
301 	.ioam6_id_wide		= IOAM6_DEFAULT_IF_ID_WIDE,
302 	.ndisc_evict_nocarrier	= 1,
303 	.ra_honor_pio_life	= 0,
304 	.ra_honor_pio_pflag	= 0,
305 };
306 
307 /* Check if link is ready: is it up and is a valid qdisc available */
308 static inline bool addrconf_link_ready(const struct net_device *dev)
309 {
310 	return netif_oper_up(dev) && !qdisc_tx_is_noop(dev);
311 }
312 
313 static void addrconf_del_rs_timer(struct inet6_dev *idev)
314 {
315 	if (del_timer(&idev->rs_timer))
316 		__in6_dev_put(idev);
317 }
318 
319 static void addrconf_del_dad_work(struct inet6_ifaddr *ifp)
320 {
321 	if (cancel_delayed_work(&ifp->dad_work))
322 		__in6_ifa_put(ifp);
323 }
324 
325 static void addrconf_mod_rs_timer(struct inet6_dev *idev,
326 				  unsigned long when)
327 {
328 	if (!mod_timer(&idev->rs_timer, jiffies + when))
329 		in6_dev_hold(idev);
330 }
331 
332 static void addrconf_mod_dad_work(struct inet6_ifaddr *ifp,
333 				   unsigned long delay)
334 {
335 	in6_ifa_hold(ifp);
336 	if (mod_delayed_work(addrconf_wq, &ifp->dad_work, delay))
337 		in6_ifa_put(ifp);
338 }
339 
340 static int snmp6_alloc_dev(struct inet6_dev *idev)
341 {
342 	int i;
343 
344 	idev->stats.ipv6 = alloc_percpu_gfp(struct ipstats_mib, GFP_KERNEL_ACCOUNT);
345 	if (!idev->stats.ipv6)
346 		goto err_ip;
347 
348 	for_each_possible_cpu(i) {
349 		struct ipstats_mib *addrconf_stats;
350 		addrconf_stats = per_cpu_ptr(idev->stats.ipv6, i);
351 		u64_stats_init(&addrconf_stats->syncp);
352 	}
353 
354 
355 	idev->stats.icmpv6dev = kzalloc(sizeof(struct icmpv6_mib_device),
356 					GFP_KERNEL);
357 	if (!idev->stats.icmpv6dev)
358 		goto err_icmp;
359 	idev->stats.icmpv6msgdev = kzalloc(sizeof(struct icmpv6msg_mib_device),
360 					   GFP_KERNEL_ACCOUNT);
361 	if (!idev->stats.icmpv6msgdev)
362 		goto err_icmpmsg;
363 
364 	return 0;
365 
366 err_icmpmsg:
367 	kfree(idev->stats.icmpv6dev);
368 err_icmp:
369 	free_percpu(idev->stats.ipv6);
370 err_ip:
371 	return -ENOMEM;
372 }
373 
374 static struct inet6_dev *ipv6_add_dev(struct net_device *dev)
375 {
376 	struct inet6_dev *ndev;
377 	int err = -ENOMEM;
378 
379 	ASSERT_RTNL();
380 
381 	if (dev->mtu < IPV6_MIN_MTU && dev != blackhole_netdev)
382 		return ERR_PTR(-EINVAL);
383 
384 	ndev = kzalloc(sizeof(*ndev), GFP_KERNEL_ACCOUNT);
385 	if (!ndev)
386 		return ERR_PTR(err);
387 
388 	rwlock_init(&ndev->lock);
389 	ndev->dev = dev;
390 	INIT_LIST_HEAD(&ndev->addr_list);
391 	timer_setup(&ndev->rs_timer, addrconf_rs_timer, 0);
392 	memcpy(&ndev->cnf, dev_net(dev)->ipv6.devconf_dflt, sizeof(ndev->cnf));
393 
394 	if (ndev->cnf.stable_secret.initialized)
395 		ndev->cnf.addr_gen_mode = IN6_ADDR_GEN_MODE_STABLE_PRIVACY;
396 
397 	ndev->cnf.mtu6 = dev->mtu;
398 	ndev->ra_mtu = 0;
399 	ndev->nd_parms = neigh_parms_alloc(dev, &nd_tbl);
400 	if (!ndev->nd_parms) {
401 		kfree(ndev);
402 		return ERR_PTR(err);
403 	}
404 	if (ndev->cnf.forwarding)
405 		dev_disable_lro(dev);
406 	/* We refer to the device */
407 	netdev_hold(dev, &ndev->dev_tracker, GFP_KERNEL);
408 
409 	if (snmp6_alloc_dev(ndev) < 0) {
410 		netdev_dbg(dev, "%s: cannot allocate memory for statistics\n",
411 			   __func__);
412 		neigh_parms_release(&nd_tbl, ndev->nd_parms);
413 		netdev_put(dev, &ndev->dev_tracker);
414 		kfree(ndev);
415 		return ERR_PTR(err);
416 	}
417 
418 	if (dev != blackhole_netdev) {
419 		if (snmp6_register_dev(ndev) < 0) {
420 			netdev_dbg(dev, "%s: cannot create /proc/net/dev_snmp6/%s\n",
421 				   __func__, dev->name);
422 			goto err_release;
423 		}
424 	}
425 	/* One reference from device. */
426 	refcount_set(&ndev->refcnt, 1);
427 
428 	if (dev->flags & (IFF_NOARP | IFF_LOOPBACK))
429 		ndev->cnf.accept_dad = -1;
430 
431 #if IS_ENABLED(CONFIG_IPV6_SIT)
432 	if (dev->type == ARPHRD_SIT && (dev->priv_flags & IFF_ISATAP)) {
433 		pr_info("%s: Disabled Multicast RS\n", dev->name);
434 		ndev->cnf.rtr_solicits = 0;
435 	}
436 #endif
437 
438 	INIT_LIST_HEAD(&ndev->tempaddr_list);
439 	ndev->desync_factor = U32_MAX;
440 	if ((dev->flags&IFF_LOOPBACK) ||
441 	    dev->type == ARPHRD_TUNNEL ||
442 	    dev->type == ARPHRD_TUNNEL6 ||
443 	    dev->type == ARPHRD_SIT ||
444 	    dev->type == ARPHRD_NONE) {
445 		ndev->cnf.use_tempaddr = -1;
446 	}
447 
448 	ndev->token = in6addr_any;
449 
450 	if (netif_running(dev) && addrconf_link_ready(dev))
451 		ndev->if_flags |= IF_READY;
452 
453 	ipv6_mc_init_dev(ndev);
454 	ndev->tstamp = jiffies;
455 	if (dev != blackhole_netdev) {
456 		err = addrconf_sysctl_register(ndev);
457 		if (err) {
458 			ipv6_mc_destroy_dev(ndev);
459 			snmp6_unregister_dev(ndev);
460 			goto err_release;
461 		}
462 	}
463 	/* protected by rtnl_lock */
464 	rcu_assign_pointer(dev->ip6_ptr, ndev);
465 
466 	if (dev != blackhole_netdev) {
467 		/* Join interface-local all-node multicast group */
468 		ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allnodes);
469 
470 		/* Join all-node multicast group */
471 		ipv6_dev_mc_inc(dev, &in6addr_linklocal_allnodes);
472 
473 		/* Join all-router multicast group if forwarding is set */
474 		if (ndev->cnf.forwarding && (dev->flags & IFF_MULTICAST))
475 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
476 	}
477 	return ndev;
478 
479 err_release:
480 	neigh_parms_release(&nd_tbl, ndev->nd_parms);
481 	ndev->dead = 1;
482 	in6_dev_finish_destroy(ndev);
483 	return ERR_PTR(err);
484 }
485 
486 static struct inet6_dev *ipv6_find_idev(struct net_device *dev)
487 {
488 	struct inet6_dev *idev;
489 
490 	ASSERT_RTNL();
491 
492 	idev = __in6_dev_get(dev);
493 	if (!idev) {
494 		idev = ipv6_add_dev(dev);
495 		if (IS_ERR(idev))
496 			return idev;
497 	}
498 
499 	if (dev->flags&IFF_UP)
500 		ipv6_mc_up(idev);
501 	return idev;
502 }
503 
504 static int inet6_netconf_msgsize_devconf(int type)
505 {
506 	int size =  NLMSG_ALIGN(sizeof(struct netconfmsg))
507 		    + nla_total_size(4);	/* NETCONFA_IFINDEX */
508 	bool all = false;
509 
510 	if (type == NETCONFA_ALL)
511 		all = true;
512 
513 	if (all || type == NETCONFA_FORWARDING)
514 		size += nla_total_size(4);
515 #ifdef CONFIG_IPV6_MROUTE
516 	if (all || type == NETCONFA_MC_FORWARDING)
517 		size += nla_total_size(4);
518 #endif
519 	if (all || type == NETCONFA_PROXY_NEIGH)
520 		size += nla_total_size(4);
521 
522 	if (all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN)
523 		size += nla_total_size(4);
524 
525 	return size;
526 }
527 
528 static int inet6_netconf_fill_devconf(struct sk_buff *skb, int ifindex,
529 				      struct ipv6_devconf *devconf, u32 portid,
530 				      u32 seq, int event, unsigned int flags,
531 				      int type)
532 {
533 	struct nlmsghdr  *nlh;
534 	struct netconfmsg *ncm;
535 	bool all = false;
536 
537 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
538 			flags);
539 	if (!nlh)
540 		return -EMSGSIZE;
541 
542 	if (type == NETCONFA_ALL)
543 		all = true;
544 
545 	ncm = nlmsg_data(nlh);
546 	ncm->ncm_family = AF_INET6;
547 
548 	if (nla_put_s32(skb, NETCONFA_IFINDEX, ifindex) < 0)
549 		goto nla_put_failure;
550 
551 	if (!devconf)
552 		goto out;
553 
554 	if ((all || type == NETCONFA_FORWARDING) &&
555 	    nla_put_s32(skb, NETCONFA_FORWARDING,
556 			READ_ONCE(devconf->forwarding)) < 0)
557 		goto nla_put_failure;
558 #ifdef CONFIG_IPV6_MROUTE
559 	if ((all || type == NETCONFA_MC_FORWARDING) &&
560 	    nla_put_s32(skb, NETCONFA_MC_FORWARDING,
561 			atomic_read(&devconf->mc_forwarding)) < 0)
562 		goto nla_put_failure;
563 #endif
564 	if ((all || type == NETCONFA_PROXY_NEIGH) &&
565 	    nla_put_s32(skb, NETCONFA_PROXY_NEIGH,
566 			READ_ONCE(devconf->proxy_ndp)) < 0)
567 		goto nla_put_failure;
568 
569 	if ((all || type == NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN) &&
570 	    nla_put_s32(skb, NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
571 			READ_ONCE(devconf->ignore_routes_with_linkdown)) < 0)
572 		goto nla_put_failure;
573 
574 out:
575 	nlmsg_end(skb, nlh);
576 	return 0;
577 
578 nla_put_failure:
579 	nlmsg_cancel(skb, nlh);
580 	return -EMSGSIZE;
581 }
582 
583 void inet6_netconf_notify_devconf(struct net *net, int event, int type,
584 				  int ifindex, struct ipv6_devconf *devconf)
585 {
586 	struct sk_buff *skb;
587 	int err = -ENOBUFS;
588 
589 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(type), GFP_KERNEL);
590 	if (!skb)
591 		goto errout;
592 
593 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf, 0, 0,
594 					 event, 0, type);
595 	if (err < 0) {
596 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
597 		WARN_ON(err == -EMSGSIZE);
598 		kfree_skb(skb);
599 		goto errout;
600 	}
601 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_NETCONF, NULL, GFP_KERNEL);
602 	return;
603 errout:
604 	rtnl_set_sk_err(net, RTNLGRP_IPV6_NETCONF, err);
605 }
606 
607 static const struct nla_policy devconf_ipv6_policy[NETCONFA_MAX+1] = {
608 	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
609 	[NETCONFA_FORWARDING]	= { .len = sizeof(int) },
610 	[NETCONFA_PROXY_NEIGH]	= { .len = sizeof(int) },
611 	[NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN]	= { .len = sizeof(int) },
612 };
613 
614 static int inet6_netconf_valid_get_req(struct sk_buff *skb,
615 				       const struct nlmsghdr *nlh,
616 				       struct nlattr **tb,
617 				       struct netlink_ext_ack *extack)
618 {
619 	int i, err;
620 
621 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(struct netconfmsg))) {
622 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf get request");
623 		return -EINVAL;
624 	}
625 
626 	if (!netlink_strict_get_check(skb))
627 		return nlmsg_parse_deprecated(nlh, sizeof(struct netconfmsg),
628 					      tb, NETCONFA_MAX,
629 					      devconf_ipv6_policy, extack);
630 
631 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct netconfmsg),
632 					    tb, NETCONFA_MAX,
633 					    devconf_ipv6_policy, extack);
634 	if (err)
635 		return err;
636 
637 	for (i = 0; i <= NETCONFA_MAX; i++) {
638 		if (!tb[i])
639 			continue;
640 
641 		switch (i) {
642 		case NETCONFA_IFINDEX:
643 			break;
644 		default:
645 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in netconf get request");
646 			return -EINVAL;
647 		}
648 	}
649 
650 	return 0;
651 }
652 
653 static int inet6_netconf_get_devconf(struct sk_buff *in_skb,
654 				     struct nlmsghdr *nlh,
655 				     struct netlink_ext_ack *extack)
656 {
657 	struct net *net = sock_net(in_skb->sk);
658 	struct nlattr *tb[NETCONFA_MAX+1];
659 	struct inet6_dev *in6_dev = NULL;
660 	struct net_device *dev = NULL;
661 	struct sk_buff *skb;
662 	struct ipv6_devconf *devconf;
663 	int ifindex;
664 	int err;
665 
666 	err = inet6_netconf_valid_get_req(in_skb, nlh, tb, extack);
667 	if (err < 0)
668 		return err;
669 
670 	if (!tb[NETCONFA_IFINDEX])
671 		return -EINVAL;
672 
673 	err = -EINVAL;
674 	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
675 	switch (ifindex) {
676 	case NETCONFA_IFINDEX_ALL:
677 		devconf = net->ipv6.devconf_all;
678 		break;
679 	case NETCONFA_IFINDEX_DEFAULT:
680 		devconf = net->ipv6.devconf_dflt;
681 		break;
682 	default:
683 		dev = dev_get_by_index(net, ifindex);
684 		if (!dev)
685 			return -EINVAL;
686 		in6_dev = in6_dev_get(dev);
687 		if (!in6_dev)
688 			goto errout;
689 		devconf = &in6_dev->cnf;
690 		break;
691 	}
692 
693 	err = -ENOBUFS;
694 	skb = nlmsg_new(inet6_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
695 	if (!skb)
696 		goto errout;
697 
698 	err = inet6_netconf_fill_devconf(skb, ifindex, devconf,
699 					 NETLINK_CB(in_skb).portid,
700 					 nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
701 					 NETCONFA_ALL);
702 	if (err < 0) {
703 		/* -EMSGSIZE implies BUG in inet6_netconf_msgsize_devconf() */
704 		WARN_ON(err == -EMSGSIZE);
705 		kfree_skb(skb);
706 		goto errout;
707 	}
708 	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
709 errout:
710 	if (in6_dev)
711 		in6_dev_put(in6_dev);
712 	dev_put(dev);
713 	return err;
714 }
715 
716 /* Combine dev_addr_genid and dev_base_seq to detect changes.
717  */
718 static u32 inet6_base_seq(const struct net *net)
719 {
720 	u32 res = atomic_read(&net->ipv6.dev_addr_genid) +
721 		  READ_ONCE(net->dev_base_seq);
722 
723 	/* Must not return 0 (see nl_dump_check_consistent()).
724 	 * Chose a value far away from 0.
725 	 */
726 	if (!res)
727 		res = 0x80000000;
728 	return res;
729 }
730 
731 static int inet6_netconf_dump_devconf(struct sk_buff *skb,
732 				      struct netlink_callback *cb)
733 {
734 	const struct nlmsghdr *nlh = cb->nlh;
735 	struct net *net = sock_net(skb->sk);
736 	struct {
737 		unsigned long ifindex;
738 		unsigned int all_default;
739 	} *ctx = (void *)cb->ctx;
740 	struct net_device *dev;
741 	struct inet6_dev *idev;
742 	int err = 0;
743 
744 	if (cb->strict_check) {
745 		struct netlink_ext_ack *extack = cb->extack;
746 		struct netconfmsg *ncm;
747 
748 		if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ncm))) {
749 			NL_SET_ERR_MSG_MOD(extack, "Invalid header for netconf dump request");
750 			return -EINVAL;
751 		}
752 
753 		if (nlmsg_attrlen(nlh, sizeof(*ncm))) {
754 			NL_SET_ERR_MSG_MOD(extack, "Invalid data after header in netconf dump request");
755 			return -EINVAL;
756 		}
757 	}
758 
759 	rcu_read_lock();
760 	for_each_netdev_dump(net, dev, ctx->ifindex) {
761 		idev = __in6_dev_get(dev);
762 		if (!idev)
763 			continue;
764 		err = inet6_netconf_fill_devconf(skb, dev->ifindex,
765 					         &idev->cnf,
766 						 NETLINK_CB(cb->skb).portid,
767 						 nlh->nlmsg_seq,
768 						 RTM_NEWNETCONF,
769 						 NLM_F_MULTI,
770 						 NETCONFA_ALL);
771 		if (err < 0)
772 			goto done;
773 	}
774 	if (ctx->all_default == 0) {
775 		err = inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_ALL,
776 						 net->ipv6.devconf_all,
777 						 NETLINK_CB(cb->skb).portid,
778 						 nlh->nlmsg_seq,
779 						 RTM_NEWNETCONF, NLM_F_MULTI,
780 						 NETCONFA_ALL);
781 		if (err < 0)
782 			goto done;
783 		ctx->all_default++;
784 	}
785 	if (ctx->all_default == 1) {
786 		err = inet6_netconf_fill_devconf(skb, NETCONFA_IFINDEX_DEFAULT,
787 						 net->ipv6.devconf_dflt,
788 						 NETLINK_CB(cb->skb).portid,
789 						 nlh->nlmsg_seq,
790 						 RTM_NEWNETCONF, NLM_F_MULTI,
791 						 NETCONFA_ALL);
792 		if (err < 0)
793 			goto done;
794 		ctx->all_default++;
795 	}
796 done:
797 	rcu_read_unlock();
798 	return err;
799 }
800 
801 #ifdef CONFIG_SYSCTL
802 static void dev_forward_change(struct inet6_dev *idev)
803 {
804 	struct net_device *dev;
805 	struct inet6_ifaddr *ifa;
806 	LIST_HEAD(tmp_addr_list);
807 
808 	if (!idev)
809 		return;
810 	dev = idev->dev;
811 	if (idev->cnf.forwarding)
812 		dev_disable_lro(dev);
813 	if (dev->flags & IFF_MULTICAST) {
814 		if (idev->cnf.forwarding) {
815 			ipv6_dev_mc_inc(dev, &in6addr_linklocal_allrouters);
816 			ipv6_dev_mc_inc(dev, &in6addr_interfacelocal_allrouters);
817 			ipv6_dev_mc_inc(dev, &in6addr_sitelocal_allrouters);
818 		} else {
819 			ipv6_dev_mc_dec(dev, &in6addr_linklocal_allrouters);
820 			ipv6_dev_mc_dec(dev, &in6addr_interfacelocal_allrouters);
821 			ipv6_dev_mc_dec(dev, &in6addr_sitelocal_allrouters);
822 		}
823 	}
824 
825 	read_lock_bh(&idev->lock);
826 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
827 		if (ifa->flags&IFA_F_TENTATIVE)
828 			continue;
829 		list_add_tail(&ifa->if_list_aux, &tmp_addr_list);
830 	}
831 	read_unlock_bh(&idev->lock);
832 
833 	while (!list_empty(&tmp_addr_list)) {
834 		ifa = list_first_entry(&tmp_addr_list,
835 				       struct inet6_ifaddr, if_list_aux);
836 		list_del(&ifa->if_list_aux);
837 		if (idev->cnf.forwarding)
838 			addrconf_join_anycast(ifa);
839 		else
840 			addrconf_leave_anycast(ifa);
841 	}
842 
843 	inet6_netconf_notify_devconf(dev_net(dev), RTM_NEWNETCONF,
844 				     NETCONFA_FORWARDING,
845 				     dev->ifindex, &idev->cnf);
846 }
847 
848 
849 static void addrconf_forward_change(struct net *net, __s32 newf)
850 {
851 	struct net_device *dev;
852 	struct inet6_dev *idev;
853 
854 	for_each_netdev(net, dev) {
855 		idev = __in6_dev_get(dev);
856 		if (idev) {
857 			int changed = (!idev->cnf.forwarding) ^ (!newf);
858 
859 			WRITE_ONCE(idev->cnf.forwarding, newf);
860 			if (changed)
861 				dev_forward_change(idev);
862 		}
863 	}
864 }
865 
866 static int addrconf_fixup_forwarding(const struct ctl_table *table, int *p, int newf)
867 {
868 	struct net *net;
869 	int old;
870 
871 	if (!rtnl_trylock())
872 		return restart_syscall();
873 
874 	net = (struct net *)table->extra2;
875 	old = *p;
876 	WRITE_ONCE(*p, newf);
877 
878 	if (p == &net->ipv6.devconf_dflt->forwarding) {
879 		if ((!newf) ^ (!old))
880 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
881 						     NETCONFA_FORWARDING,
882 						     NETCONFA_IFINDEX_DEFAULT,
883 						     net->ipv6.devconf_dflt);
884 		rtnl_unlock();
885 		return 0;
886 	}
887 
888 	if (p == &net->ipv6.devconf_all->forwarding) {
889 		int old_dflt = net->ipv6.devconf_dflt->forwarding;
890 
891 		WRITE_ONCE(net->ipv6.devconf_dflt->forwarding, newf);
892 		if ((!newf) ^ (!old_dflt))
893 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
894 						     NETCONFA_FORWARDING,
895 						     NETCONFA_IFINDEX_DEFAULT,
896 						     net->ipv6.devconf_dflt);
897 
898 		addrconf_forward_change(net, newf);
899 		if ((!newf) ^ (!old))
900 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
901 						     NETCONFA_FORWARDING,
902 						     NETCONFA_IFINDEX_ALL,
903 						     net->ipv6.devconf_all);
904 	} else if ((!newf) ^ (!old))
905 		dev_forward_change((struct inet6_dev *)table->extra1);
906 	rtnl_unlock();
907 
908 	if (newf)
909 		rt6_purge_dflt_routers(net);
910 	return 1;
911 }
912 
913 static void addrconf_linkdown_change(struct net *net, __s32 newf)
914 {
915 	struct net_device *dev;
916 	struct inet6_dev *idev;
917 
918 	for_each_netdev(net, dev) {
919 		idev = __in6_dev_get(dev);
920 		if (idev) {
921 			int changed = (!idev->cnf.ignore_routes_with_linkdown) ^ (!newf);
922 
923 			WRITE_ONCE(idev->cnf.ignore_routes_with_linkdown, newf);
924 			if (changed)
925 				inet6_netconf_notify_devconf(dev_net(dev),
926 							     RTM_NEWNETCONF,
927 							     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
928 							     dev->ifindex,
929 							     &idev->cnf);
930 		}
931 	}
932 }
933 
934 static int addrconf_fixup_linkdown(const struct ctl_table *table, int *p, int newf)
935 {
936 	struct net *net;
937 	int old;
938 
939 	if (!rtnl_trylock())
940 		return restart_syscall();
941 
942 	net = (struct net *)table->extra2;
943 	old = *p;
944 	WRITE_ONCE(*p, newf);
945 
946 	if (p == &net->ipv6.devconf_dflt->ignore_routes_with_linkdown) {
947 		if ((!newf) ^ (!old))
948 			inet6_netconf_notify_devconf(net,
949 						     RTM_NEWNETCONF,
950 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
951 						     NETCONFA_IFINDEX_DEFAULT,
952 						     net->ipv6.devconf_dflt);
953 		rtnl_unlock();
954 		return 0;
955 	}
956 
957 	if (p == &net->ipv6.devconf_all->ignore_routes_with_linkdown) {
958 		WRITE_ONCE(net->ipv6.devconf_dflt->ignore_routes_with_linkdown, newf);
959 		addrconf_linkdown_change(net, newf);
960 		if ((!newf) ^ (!old))
961 			inet6_netconf_notify_devconf(net,
962 						     RTM_NEWNETCONF,
963 						     NETCONFA_IGNORE_ROUTES_WITH_LINKDOWN,
964 						     NETCONFA_IFINDEX_ALL,
965 						     net->ipv6.devconf_all);
966 	}
967 	rtnl_unlock();
968 
969 	return 1;
970 }
971 
972 #endif
973 
974 /* Nobody refers to this ifaddr, destroy it */
975 void inet6_ifa_finish_destroy(struct inet6_ifaddr *ifp)
976 {
977 	WARN_ON(!hlist_unhashed(&ifp->addr_lst));
978 
979 #ifdef NET_REFCNT_DEBUG
980 	pr_debug("%s\n", __func__);
981 #endif
982 
983 	in6_dev_put(ifp->idev);
984 
985 	if (cancel_delayed_work(&ifp->dad_work))
986 		pr_notice("delayed DAD work was pending while freeing ifa=%p\n",
987 			  ifp);
988 
989 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
990 		pr_warn("Freeing alive inet6 address %p\n", ifp);
991 		return;
992 	}
993 
994 	kfree_rcu(ifp, rcu);
995 }
996 
997 static void
998 ipv6_link_dev_addr(struct inet6_dev *idev, struct inet6_ifaddr *ifp)
999 {
1000 	struct list_head *p;
1001 	int ifp_scope = ipv6_addr_src_scope(&ifp->addr);
1002 
1003 	/*
1004 	 * Each device address list is sorted in order of scope -
1005 	 * global before linklocal.
1006 	 */
1007 	list_for_each(p, &idev->addr_list) {
1008 		struct inet6_ifaddr *ifa
1009 			= list_entry(p, struct inet6_ifaddr, if_list);
1010 		if (ifp_scope >= ipv6_addr_src_scope(&ifa->addr))
1011 			break;
1012 	}
1013 
1014 	list_add_tail_rcu(&ifp->if_list, p);
1015 }
1016 
1017 static u32 inet6_addr_hash(const struct net *net, const struct in6_addr *addr)
1018 {
1019 	u32 val = ipv6_addr_hash(addr) ^ net_hash_mix(net);
1020 
1021 	return hash_32(val, IN6_ADDR_HSIZE_SHIFT);
1022 }
1023 
1024 static bool ipv6_chk_same_addr(struct net *net, const struct in6_addr *addr,
1025 			       struct net_device *dev, unsigned int hash)
1026 {
1027 	struct inet6_ifaddr *ifp;
1028 
1029 	hlist_for_each_entry(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
1030 		if (ipv6_addr_equal(&ifp->addr, addr)) {
1031 			if (!dev || ifp->idev->dev == dev)
1032 				return true;
1033 		}
1034 	}
1035 	return false;
1036 }
1037 
1038 static int ipv6_add_addr_hash(struct net_device *dev, struct inet6_ifaddr *ifa)
1039 {
1040 	struct net *net = dev_net(dev);
1041 	unsigned int hash = inet6_addr_hash(net, &ifa->addr);
1042 	int err = 0;
1043 
1044 	spin_lock_bh(&net->ipv6.addrconf_hash_lock);
1045 
1046 	/* Ignore adding duplicate addresses on an interface */
1047 	if (ipv6_chk_same_addr(net, &ifa->addr, dev, hash)) {
1048 		netdev_dbg(dev, "ipv6_add_addr: already assigned\n");
1049 		err = -EEXIST;
1050 	} else {
1051 		hlist_add_head_rcu(&ifa->addr_lst, &net->ipv6.inet6_addr_lst[hash]);
1052 	}
1053 
1054 	spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
1055 
1056 	return err;
1057 }
1058 
1059 /* On success it returns ifp with increased reference count */
1060 
1061 static struct inet6_ifaddr *
1062 ipv6_add_addr(struct inet6_dev *idev, struct ifa6_config *cfg,
1063 	      bool can_block, struct netlink_ext_ack *extack)
1064 {
1065 	gfp_t gfp_flags = can_block ? GFP_KERNEL : GFP_ATOMIC;
1066 	int addr_type = ipv6_addr_type(cfg->pfx);
1067 	struct net *net = dev_net(idev->dev);
1068 	struct inet6_ifaddr *ifa = NULL;
1069 	struct fib6_info *f6i = NULL;
1070 	int err = 0;
1071 
1072 	if (addr_type == IPV6_ADDR_ANY) {
1073 		NL_SET_ERR_MSG_MOD(extack, "Invalid address");
1074 		return ERR_PTR(-EADDRNOTAVAIL);
1075 	} else if (addr_type & IPV6_ADDR_MULTICAST &&
1076 		   !(cfg->ifa_flags & IFA_F_MCAUTOJOIN)) {
1077 		NL_SET_ERR_MSG_MOD(extack, "Cannot assign multicast address without \"IFA_F_MCAUTOJOIN\" flag");
1078 		return ERR_PTR(-EADDRNOTAVAIL);
1079 	} else if (!(idev->dev->flags & IFF_LOOPBACK) &&
1080 		   !netif_is_l3_master(idev->dev) &&
1081 		   addr_type & IPV6_ADDR_LOOPBACK) {
1082 		NL_SET_ERR_MSG_MOD(extack, "Cannot assign loopback address on this device");
1083 		return ERR_PTR(-EADDRNOTAVAIL);
1084 	}
1085 
1086 	if (idev->dead) {
1087 		NL_SET_ERR_MSG_MOD(extack, "device is going away");
1088 		err = -ENODEV;
1089 		goto out;
1090 	}
1091 
1092 	if (idev->cnf.disable_ipv6) {
1093 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
1094 		err = -EACCES;
1095 		goto out;
1096 	}
1097 
1098 	/* validator notifier needs to be blocking;
1099 	 * do not call in atomic context
1100 	 */
1101 	if (can_block) {
1102 		struct in6_validator_info i6vi = {
1103 			.i6vi_addr = *cfg->pfx,
1104 			.i6vi_dev = idev,
1105 			.extack = extack,
1106 		};
1107 
1108 		err = inet6addr_validator_notifier_call_chain(NETDEV_UP, &i6vi);
1109 		err = notifier_to_errno(err);
1110 		if (err < 0)
1111 			goto out;
1112 	}
1113 
1114 	ifa = kzalloc(sizeof(*ifa), gfp_flags | __GFP_ACCOUNT);
1115 	if (!ifa) {
1116 		err = -ENOBUFS;
1117 		goto out;
1118 	}
1119 
1120 	f6i = addrconf_f6i_alloc(net, idev, cfg->pfx, false, gfp_flags, extack);
1121 	if (IS_ERR(f6i)) {
1122 		err = PTR_ERR(f6i);
1123 		f6i = NULL;
1124 		goto out;
1125 	}
1126 
1127 	neigh_parms_data_state_setall(idev->nd_parms);
1128 
1129 	ifa->addr = *cfg->pfx;
1130 	if (cfg->peer_pfx)
1131 		ifa->peer_addr = *cfg->peer_pfx;
1132 
1133 	spin_lock_init(&ifa->lock);
1134 	INIT_DELAYED_WORK(&ifa->dad_work, addrconf_dad_work);
1135 	INIT_HLIST_NODE(&ifa->addr_lst);
1136 	ifa->scope = cfg->scope;
1137 	ifa->prefix_len = cfg->plen;
1138 	ifa->rt_priority = cfg->rt_priority;
1139 	ifa->flags = cfg->ifa_flags;
1140 	ifa->ifa_proto = cfg->ifa_proto;
1141 	/* No need to add the TENTATIVE flag for addresses with NODAD */
1142 	if (!(cfg->ifa_flags & IFA_F_NODAD))
1143 		ifa->flags |= IFA_F_TENTATIVE;
1144 	ifa->valid_lft = cfg->valid_lft;
1145 	ifa->prefered_lft = cfg->preferred_lft;
1146 	ifa->cstamp = ifa->tstamp = jiffies;
1147 	ifa->tokenized = false;
1148 
1149 	ifa->rt = f6i;
1150 
1151 	ifa->idev = idev;
1152 	in6_dev_hold(idev);
1153 
1154 	/* For caller */
1155 	refcount_set(&ifa->refcnt, 1);
1156 
1157 	rcu_read_lock();
1158 
1159 	err = ipv6_add_addr_hash(idev->dev, ifa);
1160 	if (err < 0) {
1161 		rcu_read_unlock();
1162 		goto out;
1163 	}
1164 
1165 	write_lock_bh(&idev->lock);
1166 
1167 	/* Add to inet6_dev unicast addr list. */
1168 	ipv6_link_dev_addr(idev, ifa);
1169 
1170 	if (ifa->flags&IFA_F_TEMPORARY) {
1171 		list_add(&ifa->tmp_list, &idev->tempaddr_list);
1172 		in6_ifa_hold(ifa);
1173 	}
1174 
1175 	in6_ifa_hold(ifa);
1176 	write_unlock_bh(&idev->lock);
1177 
1178 	rcu_read_unlock();
1179 
1180 	inet6addr_notifier_call_chain(NETDEV_UP, ifa);
1181 out:
1182 	if (unlikely(err < 0)) {
1183 		fib6_info_release(f6i);
1184 
1185 		if (ifa) {
1186 			if (ifa->idev)
1187 				in6_dev_put(ifa->idev);
1188 			kfree(ifa);
1189 		}
1190 		ifa = ERR_PTR(err);
1191 	}
1192 
1193 	return ifa;
1194 }
1195 
1196 enum cleanup_prefix_rt_t {
1197 	CLEANUP_PREFIX_RT_NOP,    /* no cleanup action for prefix route */
1198 	CLEANUP_PREFIX_RT_DEL,    /* delete the prefix route */
1199 	CLEANUP_PREFIX_RT_EXPIRE, /* update the lifetime of the prefix route */
1200 };
1201 
1202 /*
1203  * Check, whether the prefix for ifp would still need a prefix route
1204  * after deleting ifp. The function returns one of the CLEANUP_PREFIX_RT_*
1205  * constants.
1206  *
1207  * 1) we don't purge prefix if address was not permanent.
1208  *    prefix is managed by its own lifetime.
1209  * 2) we also don't purge, if the address was IFA_F_NOPREFIXROUTE.
1210  * 3) if there are no addresses, delete prefix.
1211  * 4) if there are still other permanent address(es),
1212  *    corresponding prefix is still permanent.
1213  * 5) if there are still other addresses with IFA_F_NOPREFIXROUTE,
1214  *    don't purge the prefix, assume user space is managing it.
1215  * 6) otherwise, update prefix lifetime to the
1216  *    longest valid lifetime among the corresponding
1217  *    addresses on the device.
1218  *    Note: subsequent RA will update lifetime.
1219  **/
1220 static enum cleanup_prefix_rt_t
1221 check_cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long *expires)
1222 {
1223 	struct inet6_ifaddr *ifa;
1224 	struct inet6_dev *idev = ifp->idev;
1225 	unsigned long lifetime;
1226 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_DEL;
1227 
1228 	*expires = jiffies;
1229 
1230 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
1231 		if (ifa == ifp)
1232 			continue;
1233 		if (ifa->prefix_len != ifp->prefix_len ||
1234 		    !ipv6_prefix_equal(&ifa->addr, &ifp->addr,
1235 				       ifp->prefix_len))
1236 			continue;
1237 		if (ifa->flags & (IFA_F_PERMANENT | IFA_F_NOPREFIXROUTE))
1238 			return CLEANUP_PREFIX_RT_NOP;
1239 
1240 		action = CLEANUP_PREFIX_RT_EXPIRE;
1241 
1242 		spin_lock(&ifa->lock);
1243 
1244 		lifetime = addrconf_timeout_fixup(ifa->valid_lft, HZ);
1245 		/*
1246 		 * Note: Because this address is
1247 		 * not permanent, lifetime <
1248 		 * LONG_MAX / HZ here.
1249 		 */
1250 		if (time_before(*expires, ifa->tstamp + lifetime * HZ))
1251 			*expires = ifa->tstamp + lifetime * HZ;
1252 		spin_unlock(&ifa->lock);
1253 	}
1254 
1255 	return action;
1256 }
1257 
1258 static void
1259 cleanup_prefix_route(struct inet6_ifaddr *ifp, unsigned long expires,
1260 		     bool del_rt, bool del_peer)
1261 {
1262 	struct fib6_table *table;
1263 	struct fib6_info *f6i;
1264 
1265 	f6i = addrconf_get_prefix_route(del_peer ? &ifp->peer_addr : &ifp->addr,
1266 					ifp->prefix_len,
1267 					ifp->idev->dev, 0, RTF_DEFAULT, true);
1268 	if (f6i) {
1269 		if (del_rt)
1270 			ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
1271 		else {
1272 			if (!(f6i->fib6_flags & RTF_EXPIRES)) {
1273 				table = f6i->fib6_table;
1274 				spin_lock_bh(&table->tb6_lock);
1275 
1276 				fib6_set_expires(f6i, expires);
1277 				fib6_add_gc_list(f6i);
1278 
1279 				spin_unlock_bh(&table->tb6_lock);
1280 			}
1281 			fib6_info_release(f6i);
1282 		}
1283 	}
1284 }
1285 
1286 
1287 /* This function wants to get referenced ifp and releases it before return */
1288 
1289 static void ipv6_del_addr(struct inet6_ifaddr *ifp)
1290 {
1291 	enum cleanup_prefix_rt_t action = CLEANUP_PREFIX_RT_NOP;
1292 	struct net *net = dev_net(ifp->idev->dev);
1293 	unsigned long expires;
1294 	int state;
1295 
1296 	ASSERT_RTNL();
1297 
1298 	spin_lock_bh(&ifp->lock);
1299 	state = ifp->state;
1300 	ifp->state = INET6_IFADDR_STATE_DEAD;
1301 	spin_unlock_bh(&ifp->lock);
1302 
1303 	if (state == INET6_IFADDR_STATE_DEAD)
1304 		goto out;
1305 
1306 	spin_lock_bh(&net->ipv6.addrconf_hash_lock);
1307 	hlist_del_init_rcu(&ifp->addr_lst);
1308 	spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
1309 
1310 	write_lock_bh(&ifp->idev->lock);
1311 
1312 	if (ifp->flags&IFA_F_TEMPORARY) {
1313 		list_del(&ifp->tmp_list);
1314 		if (ifp->ifpub) {
1315 			in6_ifa_put(ifp->ifpub);
1316 			ifp->ifpub = NULL;
1317 		}
1318 		__in6_ifa_put(ifp);
1319 	}
1320 
1321 	if (ifp->flags & IFA_F_PERMANENT && !(ifp->flags & IFA_F_NOPREFIXROUTE))
1322 		action = check_cleanup_prefix_route(ifp, &expires);
1323 
1324 	list_del_rcu(&ifp->if_list);
1325 	__in6_ifa_put(ifp);
1326 
1327 	write_unlock_bh(&ifp->idev->lock);
1328 
1329 	addrconf_del_dad_work(ifp);
1330 
1331 	ipv6_ifa_notify(RTM_DELADDR, ifp);
1332 
1333 	inet6addr_notifier_call_chain(NETDEV_DOWN, ifp);
1334 
1335 	if (action != CLEANUP_PREFIX_RT_NOP) {
1336 		cleanup_prefix_route(ifp, expires,
1337 			action == CLEANUP_PREFIX_RT_DEL, false);
1338 	}
1339 
1340 	/* clean up prefsrc entries */
1341 	rt6_remove_prefsrc(ifp);
1342 out:
1343 	in6_ifa_put(ifp);
1344 }
1345 
1346 static unsigned long ipv6_get_regen_advance(const struct inet6_dev *idev)
1347 {
1348 	return READ_ONCE(idev->cnf.regen_min_advance) +
1349 		READ_ONCE(idev->cnf.regen_max_retry) *
1350 		READ_ONCE(idev->cnf.dad_transmits) *
1351 		max(NEIGH_VAR(idev->nd_parms, RETRANS_TIME), HZ/100) / HZ;
1352 }
1353 
1354 static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, bool block)
1355 {
1356 	struct inet6_dev *idev = ifp->idev;
1357 	unsigned long tmp_tstamp, age;
1358 	unsigned long regen_advance;
1359 	unsigned long now = jiffies;
1360 	u32 if_public_preferred_lft;
1361 	s32 cnf_temp_preferred_lft;
1362 	struct inet6_ifaddr *ift;
1363 	struct ifa6_config cfg;
1364 	long max_desync_factor;
1365 	struct in6_addr addr;
1366 	int ret = 0;
1367 
1368 	write_lock_bh(&idev->lock);
1369 
1370 retry:
1371 	in6_dev_hold(idev);
1372 	if (READ_ONCE(idev->cnf.use_tempaddr) <= 0) {
1373 		write_unlock_bh(&idev->lock);
1374 		pr_info("%s: use_tempaddr is disabled\n", __func__);
1375 		in6_dev_put(idev);
1376 		ret = -1;
1377 		goto out;
1378 	}
1379 	spin_lock_bh(&ifp->lock);
1380 	if (ifp->regen_count++ >= READ_ONCE(idev->cnf.regen_max_retry)) {
1381 		WRITE_ONCE(idev->cnf.use_tempaddr, -1);	/*XXX*/
1382 		spin_unlock_bh(&ifp->lock);
1383 		write_unlock_bh(&idev->lock);
1384 		pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
1385 			__func__);
1386 		in6_dev_put(idev);
1387 		ret = -1;
1388 		goto out;
1389 	}
1390 	in6_ifa_hold(ifp);
1391 	memcpy(addr.s6_addr, ifp->addr.s6_addr, 8);
1392 	ipv6_gen_rnd_iid(&addr);
1393 
1394 	age = (now - ifp->tstamp) / HZ;
1395 
1396 	regen_advance = ipv6_get_regen_advance(idev);
1397 
1398 	/* recalculate max_desync_factor each time and update
1399 	 * idev->desync_factor if it's larger
1400 	 */
1401 	cnf_temp_preferred_lft = READ_ONCE(idev->cnf.temp_prefered_lft);
1402 	max_desync_factor = min_t(long,
1403 				  READ_ONCE(idev->cnf.max_desync_factor),
1404 				  cnf_temp_preferred_lft - regen_advance);
1405 
1406 	if (unlikely(idev->desync_factor > max_desync_factor)) {
1407 		if (max_desync_factor > 0) {
1408 			get_random_bytes(&idev->desync_factor,
1409 					 sizeof(idev->desync_factor));
1410 			idev->desync_factor %= max_desync_factor;
1411 		} else {
1412 			idev->desync_factor = 0;
1413 		}
1414 	}
1415 
1416 	if_public_preferred_lft = ifp->prefered_lft;
1417 
1418 	memset(&cfg, 0, sizeof(cfg));
1419 	cfg.valid_lft = min_t(__u32, ifp->valid_lft,
1420 			      READ_ONCE(idev->cnf.temp_valid_lft) + age);
1421 	cfg.preferred_lft = cnf_temp_preferred_lft + age - idev->desync_factor;
1422 	cfg.preferred_lft = min_t(__u32, if_public_preferred_lft, cfg.preferred_lft);
1423 	cfg.preferred_lft = min_t(__u32, cfg.valid_lft, cfg.preferred_lft);
1424 
1425 	cfg.plen = ifp->prefix_len;
1426 	tmp_tstamp = ifp->tstamp;
1427 	spin_unlock_bh(&ifp->lock);
1428 
1429 	write_unlock_bh(&idev->lock);
1430 
1431 	/* From RFC 4941:
1432 	 *
1433 	 *     A temporary address is created only if this calculated Preferred
1434 	 *     Lifetime is greater than REGEN_ADVANCE time units.  In
1435 	 *     particular, an implementation must not create a temporary address
1436 	 *     with a zero Preferred Lifetime.
1437 	 *
1438 	 *     ...
1439 	 *
1440 	 *     When creating a temporary address, the lifetime values MUST be
1441 	 *     derived from the corresponding prefix as follows:
1442 	 *
1443 	 *     ...
1444 	 *
1445 	 *     *  Its Preferred Lifetime is the lower of the Preferred Lifetime
1446 	 *        of the public address or TEMP_PREFERRED_LIFETIME -
1447 	 *        DESYNC_FACTOR.
1448 	 *
1449 	 * To comply with the RFC's requirements, clamp the preferred lifetime
1450 	 * to a minimum of regen_advance, unless that would exceed valid_lft or
1451 	 * ifp->prefered_lft.
1452 	 *
1453 	 * Use age calculation as in addrconf_verify to avoid unnecessary
1454 	 * temporary addresses being generated.
1455 	 */
1456 	age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
1457 	if (cfg.preferred_lft <= regen_advance + age) {
1458 		cfg.preferred_lft = regen_advance + age + 1;
1459 		if (cfg.preferred_lft > cfg.valid_lft ||
1460 		    cfg.preferred_lft > if_public_preferred_lft) {
1461 			in6_ifa_put(ifp);
1462 			in6_dev_put(idev);
1463 			ret = -1;
1464 			goto out;
1465 		}
1466 	}
1467 
1468 	cfg.ifa_flags = IFA_F_TEMPORARY;
1469 	/* set in addrconf_prefix_rcv() */
1470 	if (ifp->flags & IFA_F_OPTIMISTIC)
1471 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
1472 
1473 	cfg.pfx = &addr;
1474 	cfg.scope = ipv6_addr_scope(cfg.pfx);
1475 
1476 	ift = ipv6_add_addr(idev, &cfg, block, NULL);
1477 	if (IS_ERR(ift)) {
1478 		in6_ifa_put(ifp);
1479 		in6_dev_put(idev);
1480 		pr_info("%s: retry temporary address regeneration\n", __func__);
1481 		write_lock_bh(&idev->lock);
1482 		goto retry;
1483 	}
1484 
1485 	spin_lock_bh(&ift->lock);
1486 	ift->ifpub = ifp;
1487 	ift->cstamp = now;
1488 	ift->tstamp = tmp_tstamp;
1489 	spin_unlock_bh(&ift->lock);
1490 
1491 	addrconf_dad_start(ift);
1492 	in6_ifa_put(ift);
1493 	in6_dev_put(idev);
1494 out:
1495 	return ret;
1496 }
1497 
1498 /*
1499  *	Choose an appropriate source address (RFC3484)
1500  */
1501 enum {
1502 	IPV6_SADDR_RULE_INIT = 0,
1503 	IPV6_SADDR_RULE_LOCAL,
1504 	IPV6_SADDR_RULE_SCOPE,
1505 	IPV6_SADDR_RULE_PREFERRED,
1506 #ifdef CONFIG_IPV6_MIP6
1507 	IPV6_SADDR_RULE_HOA,
1508 #endif
1509 	IPV6_SADDR_RULE_OIF,
1510 	IPV6_SADDR_RULE_LABEL,
1511 	IPV6_SADDR_RULE_PRIVACY,
1512 	IPV6_SADDR_RULE_ORCHID,
1513 	IPV6_SADDR_RULE_PREFIX,
1514 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1515 	IPV6_SADDR_RULE_NOT_OPTIMISTIC,
1516 #endif
1517 	IPV6_SADDR_RULE_MAX
1518 };
1519 
1520 struct ipv6_saddr_score {
1521 	int			rule;
1522 	int			addr_type;
1523 	struct inet6_ifaddr	*ifa;
1524 	DECLARE_BITMAP(scorebits, IPV6_SADDR_RULE_MAX);
1525 	int			scopedist;
1526 	int			matchlen;
1527 };
1528 
1529 struct ipv6_saddr_dst {
1530 	const struct in6_addr *addr;
1531 	int ifindex;
1532 	int scope;
1533 	int label;
1534 	unsigned int prefs;
1535 };
1536 
1537 static inline int ipv6_saddr_preferred(int type)
1538 {
1539 	if (type & (IPV6_ADDR_MAPPED|IPV6_ADDR_COMPATv4|IPV6_ADDR_LOOPBACK))
1540 		return 1;
1541 	return 0;
1542 }
1543 
1544 static bool ipv6_use_optimistic_addr(const struct net *net,
1545 				     const struct inet6_dev *idev)
1546 {
1547 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1548 	if (!idev)
1549 		return false;
1550 	if (!READ_ONCE(net->ipv6.devconf_all->optimistic_dad) &&
1551 	    !READ_ONCE(idev->cnf.optimistic_dad))
1552 		return false;
1553 	if (!READ_ONCE(net->ipv6.devconf_all->use_optimistic) &&
1554 	    !READ_ONCE(idev->cnf.use_optimistic))
1555 		return false;
1556 
1557 	return true;
1558 #else
1559 	return false;
1560 #endif
1561 }
1562 
1563 static bool ipv6_allow_optimistic_dad(const struct net *net,
1564 				      const struct inet6_dev *idev)
1565 {
1566 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1567 	if (!idev)
1568 		return false;
1569 	if (!READ_ONCE(net->ipv6.devconf_all->optimistic_dad) &&
1570 	    !READ_ONCE(idev->cnf.optimistic_dad))
1571 		return false;
1572 
1573 	return true;
1574 #else
1575 	return false;
1576 #endif
1577 }
1578 
1579 static int ipv6_get_saddr_eval(struct net *net,
1580 			       struct ipv6_saddr_score *score,
1581 			       struct ipv6_saddr_dst *dst,
1582 			       int i)
1583 {
1584 	int ret;
1585 
1586 	if (i <= score->rule) {
1587 		switch (i) {
1588 		case IPV6_SADDR_RULE_SCOPE:
1589 			ret = score->scopedist;
1590 			break;
1591 		case IPV6_SADDR_RULE_PREFIX:
1592 			ret = score->matchlen;
1593 			break;
1594 		default:
1595 			ret = !!test_bit(i, score->scorebits);
1596 		}
1597 		goto out;
1598 	}
1599 
1600 	switch (i) {
1601 	case IPV6_SADDR_RULE_INIT:
1602 		/* Rule 0: remember if hiscore is not ready yet */
1603 		ret = !!score->ifa;
1604 		break;
1605 	case IPV6_SADDR_RULE_LOCAL:
1606 		/* Rule 1: Prefer same address */
1607 		ret = ipv6_addr_equal(&score->ifa->addr, dst->addr);
1608 		break;
1609 	case IPV6_SADDR_RULE_SCOPE:
1610 		/* Rule 2: Prefer appropriate scope
1611 		 *
1612 		 *      ret
1613 		 *       ^
1614 		 *    -1 |  d 15
1615 		 *    ---+--+-+---> scope
1616 		 *       |
1617 		 *       |             d is scope of the destination.
1618 		 *  B-d  |  \
1619 		 *       |   \      <- smaller scope is better if
1620 		 *  B-15 |    \        if scope is enough for destination.
1621 		 *       |             ret = B - scope (-1 <= scope >= d <= 15).
1622 		 * d-C-1 | /
1623 		 *       |/         <- greater is better
1624 		 *   -C  /             if scope is not enough for destination.
1625 		 *      /|             ret = scope - C (-1 <= d < scope <= 15).
1626 		 *
1627 		 * d - C - 1 < B -15 (for all -1 <= d <= 15).
1628 		 * C > d + 14 - B >= 15 + 14 - B = 29 - B.
1629 		 * Assume B = 0 and we get C > 29.
1630 		 */
1631 		ret = __ipv6_addr_src_scope(score->addr_type);
1632 		if (ret >= dst->scope)
1633 			ret = -ret;
1634 		else
1635 			ret -= 128;	/* 30 is enough */
1636 		score->scopedist = ret;
1637 		break;
1638 	case IPV6_SADDR_RULE_PREFERRED:
1639 	    {
1640 		/* Rule 3: Avoid deprecated and optimistic addresses */
1641 		u8 avoid = IFA_F_DEPRECATED;
1642 
1643 		if (!ipv6_use_optimistic_addr(net, score->ifa->idev))
1644 			avoid |= IFA_F_OPTIMISTIC;
1645 		ret = ipv6_saddr_preferred(score->addr_type) ||
1646 		      !(score->ifa->flags & avoid);
1647 		break;
1648 	    }
1649 #ifdef CONFIG_IPV6_MIP6
1650 	case IPV6_SADDR_RULE_HOA:
1651 	    {
1652 		/* Rule 4: Prefer home address */
1653 		int prefhome = !(dst->prefs & IPV6_PREFER_SRC_COA);
1654 		ret = !(score->ifa->flags & IFA_F_HOMEADDRESS) ^ prefhome;
1655 		break;
1656 	    }
1657 #endif
1658 	case IPV6_SADDR_RULE_OIF:
1659 		/* Rule 5: Prefer outgoing interface */
1660 		ret = (!dst->ifindex ||
1661 		       dst->ifindex == score->ifa->idev->dev->ifindex);
1662 		break;
1663 	case IPV6_SADDR_RULE_LABEL:
1664 		/* Rule 6: Prefer matching label */
1665 		ret = ipv6_addr_label(net,
1666 				      &score->ifa->addr, score->addr_type,
1667 				      score->ifa->idev->dev->ifindex) == dst->label;
1668 		break;
1669 	case IPV6_SADDR_RULE_PRIVACY:
1670 	    {
1671 		/* Rule 7: Prefer public address
1672 		 * Note: prefer temporary address if use_tempaddr >= 2
1673 		 */
1674 		int preftmp = dst->prefs & (IPV6_PREFER_SRC_PUBLIC|IPV6_PREFER_SRC_TMP) ?
1675 				!!(dst->prefs & IPV6_PREFER_SRC_TMP) :
1676 				READ_ONCE(score->ifa->idev->cnf.use_tempaddr) >= 2;
1677 		ret = (!(score->ifa->flags & IFA_F_TEMPORARY)) ^ preftmp;
1678 		break;
1679 	    }
1680 	case IPV6_SADDR_RULE_ORCHID:
1681 		/* Rule 8-: Prefer ORCHID vs ORCHID or
1682 		 *	    non-ORCHID vs non-ORCHID
1683 		 */
1684 		ret = !(ipv6_addr_orchid(&score->ifa->addr) ^
1685 			ipv6_addr_orchid(dst->addr));
1686 		break;
1687 	case IPV6_SADDR_RULE_PREFIX:
1688 		/* Rule 8: Use longest matching prefix */
1689 		ret = ipv6_addr_diff(&score->ifa->addr, dst->addr);
1690 		if (ret > score->ifa->prefix_len)
1691 			ret = score->ifa->prefix_len;
1692 		score->matchlen = ret;
1693 		break;
1694 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
1695 	case IPV6_SADDR_RULE_NOT_OPTIMISTIC:
1696 		/* Optimistic addresses still have lower precedence than other
1697 		 * preferred addresses.
1698 		 */
1699 		ret = !(score->ifa->flags & IFA_F_OPTIMISTIC);
1700 		break;
1701 #endif
1702 	default:
1703 		ret = 0;
1704 	}
1705 
1706 	if (ret)
1707 		__set_bit(i, score->scorebits);
1708 	score->rule = i;
1709 out:
1710 	return ret;
1711 }
1712 
1713 static int __ipv6_dev_get_saddr(struct net *net,
1714 				struct ipv6_saddr_dst *dst,
1715 				struct inet6_dev *idev,
1716 				struct ipv6_saddr_score *scores,
1717 				int hiscore_idx)
1718 {
1719 	struct ipv6_saddr_score *score = &scores[1 - hiscore_idx], *hiscore = &scores[hiscore_idx];
1720 
1721 	list_for_each_entry_rcu(score->ifa, &idev->addr_list, if_list) {
1722 		int i;
1723 
1724 		/*
1725 		 * - Tentative Address (RFC2462 section 5.4)
1726 		 *  - A tentative address is not considered
1727 		 *    "assigned to an interface" in the traditional
1728 		 *    sense, unless it is also flagged as optimistic.
1729 		 * - Candidate Source Address (section 4)
1730 		 *  - In any case, anycast addresses, multicast
1731 		 *    addresses, and the unspecified address MUST
1732 		 *    NOT be included in a candidate set.
1733 		 */
1734 		if ((score->ifa->flags & IFA_F_TENTATIVE) &&
1735 		    (!(score->ifa->flags & IFA_F_OPTIMISTIC)))
1736 			continue;
1737 
1738 		score->addr_type = __ipv6_addr_type(&score->ifa->addr);
1739 
1740 		if (unlikely(score->addr_type == IPV6_ADDR_ANY ||
1741 			     score->addr_type & IPV6_ADDR_MULTICAST)) {
1742 			net_dbg_ratelimited("ADDRCONF: unspecified / multicast address assigned as unicast address on %s",
1743 					    idev->dev->name);
1744 			continue;
1745 		}
1746 
1747 		score->rule = -1;
1748 		bitmap_zero(score->scorebits, IPV6_SADDR_RULE_MAX);
1749 
1750 		for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
1751 			int minihiscore, miniscore;
1752 
1753 			minihiscore = ipv6_get_saddr_eval(net, hiscore, dst, i);
1754 			miniscore = ipv6_get_saddr_eval(net, score, dst, i);
1755 
1756 			if (minihiscore > miniscore) {
1757 				if (i == IPV6_SADDR_RULE_SCOPE &&
1758 				    score->scopedist > 0) {
1759 					/*
1760 					 * special case:
1761 					 * each remaining entry
1762 					 * has too small (not enough)
1763 					 * scope, because ifa entries
1764 					 * are sorted by their scope
1765 					 * values.
1766 					 */
1767 					goto out;
1768 				}
1769 				break;
1770 			} else if (minihiscore < miniscore) {
1771 				swap(hiscore, score);
1772 				hiscore_idx = 1 - hiscore_idx;
1773 
1774 				/* restore our iterator */
1775 				score->ifa = hiscore->ifa;
1776 
1777 				break;
1778 			}
1779 		}
1780 	}
1781 out:
1782 	return hiscore_idx;
1783 }
1784 
1785 static int ipv6_get_saddr_master(struct net *net,
1786 				 const struct net_device *dst_dev,
1787 				 const struct net_device *master,
1788 				 struct ipv6_saddr_dst *dst,
1789 				 struct ipv6_saddr_score *scores,
1790 				 int hiscore_idx)
1791 {
1792 	struct inet6_dev *idev;
1793 
1794 	idev = __in6_dev_get(dst_dev);
1795 	if (idev)
1796 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1797 						   scores, hiscore_idx);
1798 
1799 	idev = __in6_dev_get(master);
1800 	if (idev)
1801 		hiscore_idx = __ipv6_dev_get_saddr(net, dst, idev,
1802 						   scores, hiscore_idx);
1803 
1804 	return hiscore_idx;
1805 }
1806 
1807 int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev,
1808 		       const struct in6_addr *daddr, unsigned int prefs,
1809 		       struct in6_addr *saddr)
1810 {
1811 	struct ipv6_saddr_score scores[2], *hiscore;
1812 	struct ipv6_saddr_dst dst;
1813 	struct inet6_dev *idev;
1814 	struct net_device *dev;
1815 	int dst_type;
1816 	bool use_oif_addr = false;
1817 	int hiscore_idx = 0;
1818 	int ret = 0;
1819 
1820 	dst_type = __ipv6_addr_type(daddr);
1821 	dst.addr = daddr;
1822 	dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
1823 	dst.scope = __ipv6_addr_src_scope(dst_type);
1824 	dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
1825 	dst.prefs = prefs;
1826 
1827 	scores[hiscore_idx].rule = -1;
1828 	scores[hiscore_idx].ifa = NULL;
1829 
1830 	rcu_read_lock();
1831 
1832 	/* Candidate Source Address (section 4)
1833 	 *  - multicast and link-local destination address,
1834 	 *    the set of candidate source address MUST only
1835 	 *    include addresses assigned to interfaces
1836 	 *    belonging to the same link as the outgoing
1837 	 *    interface.
1838 	 * (- For site-local destination addresses, the
1839 	 *    set of candidate source addresses MUST only
1840 	 *    include addresses assigned to interfaces
1841 	 *    belonging to the same site as the outgoing
1842 	 *    interface.)
1843 	 *  - "It is RECOMMENDED that the candidate source addresses
1844 	 *    be the set of unicast addresses assigned to the
1845 	 *    interface that will be used to send to the destination
1846 	 *    (the 'outgoing' interface)." (RFC 6724)
1847 	 */
1848 	if (dst_dev) {
1849 		idev = __in6_dev_get(dst_dev);
1850 		if ((dst_type & IPV6_ADDR_MULTICAST) ||
1851 		    dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
1852 		    (idev && READ_ONCE(idev->cnf.use_oif_addrs_only))) {
1853 			use_oif_addr = true;
1854 		}
1855 	}
1856 
1857 	if (use_oif_addr) {
1858 		if (idev)
1859 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1860 	} else {
1861 		const struct net_device *master;
1862 		int master_idx = 0;
1863 
1864 		/* if dst_dev exists and is enslaved to an L3 device, then
1865 		 * prefer addresses from dst_dev and then the master over
1866 		 * any other enslaved devices in the L3 domain.
1867 		 */
1868 		master = l3mdev_master_dev_rcu(dst_dev);
1869 		if (master) {
1870 			master_idx = master->ifindex;
1871 
1872 			hiscore_idx = ipv6_get_saddr_master(net, dst_dev,
1873 							    master, &dst,
1874 							    scores, hiscore_idx);
1875 
1876 			if (scores[hiscore_idx].ifa &&
1877 			    scores[hiscore_idx].scopedist >= 0)
1878 				goto out;
1879 		}
1880 
1881 		for_each_netdev_rcu(net, dev) {
1882 			/* only consider addresses on devices in the
1883 			 * same L3 domain
1884 			 */
1885 			if (l3mdev_master_ifindex_rcu(dev) != master_idx)
1886 				continue;
1887 			idev = __in6_dev_get(dev);
1888 			if (!idev)
1889 				continue;
1890 			hiscore_idx = __ipv6_dev_get_saddr(net, &dst, idev, scores, hiscore_idx);
1891 		}
1892 	}
1893 
1894 out:
1895 	hiscore = &scores[hiscore_idx];
1896 	if (!hiscore->ifa)
1897 		ret = -EADDRNOTAVAIL;
1898 	else
1899 		*saddr = hiscore->ifa->addr;
1900 
1901 	rcu_read_unlock();
1902 	return ret;
1903 }
1904 EXPORT_SYMBOL(ipv6_dev_get_saddr);
1905 
1906 static int __ipv6_get_lladdr(struct inet6_dev *idev, struct in6_addr *addr,
1907 			      u32 banned_flags)
1908 {
1909 	struct inet6_ifaddr *ifp;
1910 	int err = -EADDRNOTAVAIL;
1911 
1912 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
1913 		if (ifp->scope > IFA_LINK)
1914 			break;
1915 		if (ifp->scope == IFA_LINK &&
1916 		    !(ifp->flags & banned_flags)) {
1917 			*addr = ifp->addr;
1918 			err = 0;
1919 			break;
1920 		}
1921 	}
1922 	return err;
1923 }
1924 
1925 int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
1926 		    u32 banned_flags)
1927 {
1928 	struct inet6_dev *idev;
1929 	int err = -EADDRNOTAVAIL;
1930 
1931 	rcu_read_lock();
1932 	idev = __in6_dev_get(dev);
1933 	if (idev) {
1934 		read_lock_bh(&idev->lock);
1935 		err = __ipv6_get_lladdr(idev, addr, banned_flags);
1936 		read_unlock_bh(&idev->lock);
1937 	}
1938 	rcu_read_unlock();
1939 	return err;
1940 }
1941 
1942 static int ipv6_count_addresses(const struct inet6_dev *idev)
1943 {
1944 	const struct inet6_ifaddr *ifp;
1945 	int cnt = 0;
1946 
1947 	rcu_read_lock();
1948 	list_for_each_entry_rcu(ifp, &idev->addr_list, if_list)
1949 		cnt++;
1950 	rcu_read_unlock();
1951 	return cnt;
1952 }
1953 
1954 int ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
1955 		  const struct net_device *dev, int strict)
1956 {
1957 	return ipv6_chk_addr_and_flags(net, addr, dev, !dev,
1958 				       strict, IFA_F_TENTATIVE);
1959 }
1960 EXPORT_SYMBOL(ipv6_chk_addr);
1961 
1962 /* device argument is used to find the L3 domain of interest. If
1963  * skip_dev_check is set, then the ifp device is not checked against
1964  * the passed in dev argument. So the 2 cases for addresses checks are:
1965  *   1. does the address exist in the L3 domain that dev is part of
1966  *      (skip_dev_check = true), or
1967  *
1968  *   2. does the address exist on the specific device
1969  *      (skip_dev_check = false)
1970  */
1971 static struct net_device *
1972 __ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
1973 			  const struct net_device *dev, bool skip_dev_check,
1974 			  int strict, u32 banned_flags)
1975 {
1976 	unsigned int hash = inet6_addr_hash(net, addr);
1977 	struct net_device *l3mdev, *ndev;
1978 	struct inet6_ifaddr *ifp;
1979 	u32 ifp_flags;
1980 
1981 	rcu_read_lock();
1982 
1983 	l3mdev = l3mdev_master_dev_rcu(dev);
1984 	if (skip_dev_check)
1985 		dev = NULL;
1986 
1987 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
1988 		ndev = ifp->idev->dev;
1989 
1990 		if (l3mdev_master_dev_rcu(ndev) != l3mdev)
1991 			continue;
1992 
1993 		/* Decouple optimistic from tentative for evaluation here.
1994 		 * Ban optimistic addresses explicitly, when required.
1995 		 */
1996 		ifp_flags = (ifp->flags&IFA_F_OPTIMISTIC)
1997 			    ? (ifp->flags&~IFA_F_TENTATIVE)
1998 			    : ifp->flags;
1999 		if (ipv6_addr_equal(&ifp->addr, addr) &&
2000 		    !(ifp_flags&banned_flags) &&
2001 		    (!dev || ndev == dev ||
2002 		     !(ifp->scope&(IFA_LINK|IFA_HOST) || strict))) {
2003 			rcu_read_unlock();
2004 			return ndev;
2005 		}
2006 	}
2007 
2008 	rcu_read_unlock();
2009 	return NULL;
2010 }
2011 
2012 int ipv6_chk_addr_and_flags(struct net *net, const struct in6_addr *addr,
2013 			    const struct net_device *dev, bool skip_dev_check,
2014 			    int strict, u32 banned_flags)
2015 {
2016 	return __ipv6_chk_addr_and_flags(net, addr, dev, skip_dev_check,
2017 					 strict, banned_flags) ? 1 : 0;
2018 }
2019 EXPORT_SYMBOL(ipv6_chk_addr_and_flags);
2020 
2021 
2022 /* Compares an address/prefix_len with addresses on device @dev.
2023  * If one is found it returns true.
2024  */
2025 bool ipv6_chk_custom_prefix(const struct in6_addr *addr,
2026 	const unsigned int prefix_len, struct net_device *dev)
2027 {
2028 	const struct inet6_ifaddr *ifa;
2029 	const struct inet6_dev *idev;
2030 	bool ret = false;
2031 
2032 	rcu_read_lock();
2033 	idev = __in6_dev_get(dev);
2034 	if (idev) {
2035 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
2036 			ret = ipv6_prefix_equal(addr, &ifa->addr, prefix_len);
2037 			if (ret)
2038 				break;
2039 		}
2040 	}
2041 	rcu_read_unlock();
2042 
2043 	return ret;
2044 }
2045 EXPORT_SYMBOL(ipv6_chk_custom_prefix);
2046 
2047 int ipv6_chk_prefix(const struct in6_addr *addr, struct net_device *dev)
2048 {
2049 	const struct inet6_ifaddr *ifa;
2050 	const struct inet6_dev *idev;
2051 	int	onlink;
2052 
2053 	onlink = 0;
2054 	rcu_read_lock();
2055 	idev = __in6_dev_get(dev);
2056 	if (idev) {
2057 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
2058 			onlink = ipv6_prefix_equal(addr, &ifa->addr,
2059 						   ifa->prefix_len);
2060 			if (onlink)
2061 				break;
2062 		}
2063 	}
2064 	rcu_read_unlock();
2065 	return onlink;
2066 }
2067 EXPORT_SYMBOL(ipv6_chk_prefix);
2068 
2069 /**
2070  * ipv6_dev_find - find the first device with a given source address.
2071  * @net: the net namespace
2072  * @addr: the source address
2073  * @dev: used to find the L3 domain of interest
2074  *
2075  * The caller should be protected by RCU, or RTNL.
2076  */
2077 struct net_device *ipv6_dev_find(struct net *net, const struct in6_addr *addr,
2078 				 struct net_device *dev)
2079 {
2080 	return __ipv6_chk_addr_and_flags(net, addr, dev, !dev, 1,
2081 					 IFA_F_TENTATIVE);
2082 }
2083 EXPORT_SYMBOL(ipv6_dev_find);
2084 
2085 struct inet6_ifaddr *ipv6_get_ifaddr(struct net *net, const struct in6_addr *addr,
2086 				     struct net_device *dev, int strict)
2087 {
2088 	unsigned int hash = inet6_addr_hash(net, addr);
2089 	struct inet6_ifaddr *ifp, *result = NULL;
2090 
2091 	rcu_read_lock();
2092 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
2093 		if (ipv6_addr_equal(&ifp->addr, addr)) {
2094 			if (!dev || ifp->idev->dev == dev ||
2095 			    !(ifp->scope&(IFA_LINK|IFA_HOST) || strict)) {
2096 				if (in6_ifa_hold_safe(ifp)) {
2097 					result = ifp;
2098 					break;
2099 				}
2100 			}
2101 		}
2102 	}
2103 	rcu_read_unlock();
2104 
2105 	return result;
2106 }
2107 
2108 /* Gets referenced address, destroys ifaddr */
2109 
2110 static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
2111 {
2112 	if (dad_failed)
2113 		ifp->flags |= IFA_F_DADFAILED;
2114 
2115 	if (ifp->flags&IFA_F_TEMPORARY) {
2116 		struct inet6_ifaddr *ifpub;
2117 		spin_lock_bh(&ifp->lock);
2118 		ifpub = ifp->ifpub;
2119 		if (ifpub) {
2120 			in6_ifa_hold(ifpub);
2121 			spin_unlock_bh(&ifp->lock);
2122 			ipv6_create_tempaddr(ifpub, true);
2123 			in6_ifa_put(ifpub);
2124 		} else {
2125 			spin_unlock_bh(&ifp->lock);
2126 		}
2127 		ipv6_del_addr(ifp);
2128 	} else if (ifp->flags&IFA_F_PERMANENT || !dad_failed) {
2129 		spin_lock_bh(&ifp->lock);
2130 		addrconf_del_dad_work(ifp);
2131 		ifp->flags |= IFA_F_TENTATIVE;
2132 		if (dad_failed)
2133 			ifp->flags &= ~IFA_F_OPTIMISTIC;
2134 		spin_unlock_bh(&ifp->lock);
2135 		if (dad_failed)
2136 			ipv6_ifa_notify(0, ifp);
2137 		in6_ifa_put(ifp);
2138 	} else {
2139 		ipv6_del_addr(ifp);
2140 	}
2141 }
2142 
2143 static int addrconf_dad_end(struct inet6_ifaddr *ifp)
2144 {
2145 	int err = -ENOENT;
2146 
2147 	spin_lock_bh(&ifp->lock);
2148 	if (ifp->state == INET6_IFADDR_STATE_DAD) {
2149 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
2150 		err = 0;
2151 	}
2152 	spin_unlock_bh(&ifp->lock);
2153 
2154 	return err;
2155 }
2156 
2157 void addrconf_dad_failure(struct sk_buff *skb, struct inet6_ifaddr *ifp)
2158 {
2159 	struct inet6_dev *idev = ifp->idev;
2160 	struct net *net = dev_net(idev->dev);
2161 	int max_addresses;
2162 
2163 	if (addrconf_dad_end(ifp)) {
2164 		in6_ifa_put(ifp);
2165 		return;
2166 	}
2167 
2168 	net_info_ratelimited("%s: IPv6 duplicate address %pI6c used by %pM detected!\n",
2169 			     ifp->idev->dev->name, &ifp->addr, eth_hdr(skb)->h_source);
2170 
2171 	spin_lock_bh(&ifp->lock);
2172 
2173 	if (ifp->flags & IFA_F_STABLE_PRIVACY) {
2174 		struct in6_addr new_addr;
2175 		struct inet6_ifaddr *ifp2;
2176 		int retries = ifp->stable_privacy_retry + 1;
2177 		struct ifa6_config cfg = {
2178 			.pfx = &new_addr,
2179 			.plen = ifp->prefix_len,
2180 			.ifa_flags = ifp->flags,
2181 			.valid_lft = ifp->valid_lft,
2182 			.preferred_lft = ifp->prefered_lft,
2183 			.scope = ifp->scope,
2184 		};
2185 
2186 		if (retries > net->ipv6.sysctl.idgen_retries) {
2187 			net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n",
2188 					     ifp->idev->dev->name);
2189 			goto errdad;
2190 		}
2191 
2192 		new_addr = ifp->addr;
2193 		if (ipv6_generate_stable_address(&new_addr, retries,
2194 						 idev))
2195 			goto errdad;
2196 
2197 		spin_unlock_bh(&ifp->lock);
2198 
2199 		max_addresses = READ_ONCE(idev->cnf.max_addresses);
2200 		if (max_addresses &&
2201 		    ipv6_count_addresses(idev) >= max_addresses)
2202 			goto lock_errdad;
2203 
2204 		net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n",
2205 				     ifp->idev->dev->name);
2206 
2207 		ifp2 = ipv6_add_addr(idev, &cfg, false, NULL);
2208 		if (IS_ERR(ifp2))
2209 			goto lock_errdad;
2210 
2211 		spin_lock_bh(&ifp2->lock);
2212 		ifp2->stable_privacy_retry = retries;
2213 		ifp2->state = INET6_IFADDR_STATE_PREDAD;
2214 		spin_unlock_bh(&ifp2->lock);
2215 
2216 		addrconf_mod_dad_work(ifp2, net->ipv6.sysctl.idgen_delay);
2217 		in6_ifa_put(ifp2);
2218 lock_errdad:
2219 		spin_lock_bh(&ifp->lock);
2220 	}
2221 
2222 errdad:
2223 	/* transition from _POSTDAD to _ERRDAD */
2224 	ifp->state = INET6_IFADDR_STATE_ERRDAD;
2225 	spin_unlock_bh(&ifp->lock);
2226 
2227 	addrconf_mod_dad_work(ifp, 0);
2228 	in6_ifa_put(ifp);
2229 }
2230 
2231 /* Join to solicited addr multicast group.
2232  * caller must hold RTNL */
2233 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr)
2234 {
2235 	struct in6_addr maddr;
2236 
2237 	if (dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2238 		return;
2239 
2240 	addrconf_addr_solict_mult(addr, &maddr);
2241 	ipv6_dev_mc_inc(dev, &maddr);
2242 }
2243 
2244 /* caller must hold RTNL */
2245 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr)
2246 {
2247 	struct in6_addr maddr;
2248 
2249 	if (idev->dev->flags&(IFF_LOOPBACK|IFF_NOARP))
2250 		return;
2251 
2252 	addrconf_addr_solict_mult(addr, &maddr);
2253 	__ipv6_dev_mc_dec(idev, &maddr);
2254 }
2255 
2256 /* caller must hold RTNL */
2257 static void addrconf_join_anycast(struct inet6_ifaddr *ifp)
2258 {
2259 	struct in6_addr addr;
2260 
2261 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2262 		return;
2263 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2264 	if (ipv6_addr_any(&addr))
2265 		return;
2266 	__ipv6_dev_ac_inc(ifp->idev, &addr);
2267 }
2268 
2269 /* caller must hold RTNL */
2270 static void addrconf_leave_anycast(struct inet6_ifaddr *ifp)
2271 {
2272 	struct in6_addr addr;
2273 
2274 	if (ifp->prefix_len >= 127) /* RFC 6164 */
2275 		return;
2276 	ipv6_addr_prefix(&addr, &ifp->addr, ifp->prefix_len);
2277 	if (ipv6_addr_any(&addr))
2278 		return;
2279 	__ipv6_dev_ac_dec(ifp->idev, &addr);
2280 }
2281 
2282 static int addrconf_ifid_6lowpan(u8 *eui, struct net_device *dev)
2283 {
2284 	switch (dev->addr_len) {
2285 	case ETH_ALEN:
2286 		memcpy(eui, dev->dev_addr, 3);
2287 		eui[3] = 0xFF;
2288 		eui[4] = 0xFE;
2289 		memcpy(eui + 5, dev->dev_addr + 3, 3);
2290 		break;
2291 	case EUI64_ADDR_LEN:
2292 		memcpy(eui, dev->dev_addr, EUI64_ADDR_LEN);
2293 		eui[0] ^= 2;
2294 		break;
2295 	default:
2296 		return -1;
2297 	}
2298 
2299 	return 0;
2300 }
2301 
2302 static int addrconf_ifid_ieee1394(u8 *eui, struct net_device *dev)
2303 {
2304 	const union fwnet_hwaddr *ha;
2305 
2306 	if (dev->addr_len != FWNET_ALEN)
2307 		return -1;
2308 
2309 	ha = (const union fwnet_hwaddr *)dev->dev_addr;
2310 
2311 	memcpy(eui, &ha->uc.uniq_id, sizeof(ha->uc.uniq_id));
2312 	eui[0] ^= 2;
2313 	return 0;
2314 }
2315 
2316 static int addrconf_ifid_arcnet(u8 *eui, struct net_device *dev)
2317 {
2318 	/* XXX: inherit EUI-64 from other interface -- yoshfuji */
2319 	if (dev->addr_len != ARCNET_ALEN)
2320 		return -1;
2321 	memset(eui, 0, 7);
2322 	eui[7] = *(u8 *)dev->dev_addr;
2323 	return 0;
2324 }
2325 
2326 static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
2327 {
2328 	if (dev->addr_len != INFINIBAND_ALEN)
2329 		return -1;
2330 	memcpy(eui, dev->dev_addr + 12, 8);
2331 	eui[0] |= 2;
2332 	return 0;
2333 }
2334 
2335 static int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
2336 {
2337 	if (addr == 0)
2338 		return -1;
2339 	eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
2340 		  ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
2341 		  ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||
2342 		  ipv4_is_anycast_6to4(addr) || ipv4_is_private_192(addr) ||
2343 		  ipv4_is_test_198(addr) || ipv4_is_multicast(addr) ||
2344 		  ipv4_is_lbcast(addr)) ? 0x00 : 0x02;
2345 	eui[1] = 0;
2346 	eui[2] = 0x5E;
2347 	eui[3] = 0xFE;
2348 	memcpy(eui + 4, &addr, 4);
2349 	return 0;
2350 }
2351 
2352 static int addrconf_ifid_sit(u8 *eui, struct net_device *dev)
2353 {
2354 	if (dev->priv_flags & IFF_ISATAP)
2355 		return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2356 	return -1;
2357 }
2358 
2359 static int addrconf_ifid_gre(u8 *eui, struct net_device *dev)
2360 {
2361 	return __ipv6_isatap_ifid(eui, *(__be32 *)dev->dev_addr);
2362 }
2363 
2364 static int addrconf_ifid_ip6tnl(u8 *eui, struct net_device *dev)
2365 {
2366 	memcpy(eui, dev->perm_addr, 3);
2367 	memcpy(eui + 5, dev->perm_addr + 3, 3);
2368 	eui[3] = 0xFF;
2369 	eui[4] = 0xFE;
2370 	eui[0] ^= 2;
2371 	return 0;
2372 }
2373 
2374 static int ipv6_generate_eui64(u8 *eui, struct net_device *dev)
2375 {
2376 	switch (dev->type) {
2377 	case ARPHRD_ETHER:
2378 	case ARPHRD_FDDI:
2379 		return addrconf_ifid_eui48(eui, dev);
2380 	case ARPHRD_ARCNET:
2381 		return addrconf_ifid_arcnet(eui, dev);
2382 	case ARPHRD_INFINIBAND:
2383 		return addrconf_ifid_infiniband(eui, dev);
2384 	case ARPHRD_SIT:
2385 		return addrconf_ifid_sit(eui, dev);
2386 	case ARPHRD_IPGRE:
2387 	case ARPHRD_TUNNEL:
2388 		return addrconf_ifid_gre(eui, dev);
2389 	case ARPHRD_6LOWPAN:
2390 		return addrconf_ifid_6lowpan(eui, dev);
2391 	case ARPHRD_IEEE1394:
2392 		return addrconf_ifid_ieee1394(eui, dev);
2393 	case ARPHRD_TUNNEL6:
2394 	case ARPHRD_IP6GRE:
2395 	case ARPHRD_RAWIP:
2396 		return addrconf_ifid_ip6tnl(eui, dev);
2397 	}
2398 	return -1;
2399 }
2400 
2401 static int ipv6_inherit_eui64(u8 *eui, struct inet6_dev *idev)
2402 {
2403 	int err = -1;
2404 	struct inet6_ifaddr *ifp;
2405 
2406 	read_lock_bh(&idev->lock);
2407 	list_for_each_entry_reverse(ifp, &idev->addr_list, if_list) {
2408 		if (ifp->scope > IFA_LINK)
2409 			break;
2410 		if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
2411 			memcpy(eui, ifp->addr.s6_addr+8, 8);
2412 			err = 0;
2413 			break;
2414 		}
2415 	}
2416 	read_unlock_bh(&idev->lock);
2417 	return err;
2418 }
2419 
2420 /* Generation of a randomized Interface Identifier
2421  * draft-ietf-6man-rfc4941bis, Section 3.3.1
2422  */
2423 
2424 static void ipv6_gen_rnd_iid(struct in6_addr *addr)
2425 {
2426 regen:
2427 	get_random_bytes(&addr->s6_addr[8], 8);
2428 
2429 	/* <draft-ietf-6man-rfc4941bis-08.txt>, Section 3.3.1:
2430 	 * check if generated address is not inappropriate:
2431 	 *
2432 	 * - Reserved IPv6 Interface Identifiers
2433 	 * - XXX: already assigned to an address on the device
2434 	 */
2435 
2436 	/* Subnet-router anycast: 0000:0000:0000:0000 */
2437 	if (!(addr->s6_addr32[2] | addr->s6_addr32[3]))
2438 		goto regen;
2439 
2440 	/* IANA Ethernet block: 0200:5EFF:FE00:0000-0200:5EFF:FE00:5212
2441 	 * Proxy Mobile IPv6:   0200:5EFF:FE00:5213
2442 	 * IANA Ethernet block: 0200:5EFF:FE00:5214-0200:5EFF:FEFF:FFFF
2443 	 */
2444 	if (ntohl(addr->s6_addr32[2]) == 0x02005eff &&
2445 	    (ntohl(addr->s6_addr32[3]) & 0Xff000000) == 0xfe000000)
2446 		goto regen;
2447 
2448 	/* Reserved subnet anycast addresses */
2449 	if (ntohl(addr->s6_addr32[2]) == 0xfdffffff &&
2450 	    ntohl(addr->s6_addr32[3]) >= 0Xffffff80)
2451 		goto regen;
2452 }
2453 
2454 /*
2455  *	Add prefix route.
2456  */
2457 
2458 static void
2459 addrconf_prefix_route(struct in6_addr *pfx, int plen, u32 metric,
2460 		      struct net_device *dev, unsigned long expires,
2461 		      u32 flags, gfp_t gfp_flags)
2462 {
2463 	struct fib6_config cfg = {
2464 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX,
2465 		.fc_metric = metric ? : IP6_RT_PRIO_ADDRCONF,
2466 		.fc_ifindex = dev->ifindex,
2467 		.fc_expires = expires,
2468 		.fc_dst_len = plen,
2469 		.fc_flags = RTF_UP | flags,
2470 		.fc_nlinfo.nl_net = dev_net(dev),
2471 		.fc_protocol = RTPROT_KERNEL,
2472 		.fc_type = RTN_UNICAST,
2473 	};
2474 
2475 	cfg.fc_dst = *pfx;
2476 
2477 	/* Prevent useless cloning on PtP SIT.
2478 	   This thing is done here expecting that the whole
2479 	   class of non-broadcast devices need not cloning.
2480 	 */
2481 #if IS_ENABLED(CONFIG_IPV6_SIT)
2482 	if (dev->type == ARPHRD_SIT && (dev->flags & IFF_POINTOPOINT))
2483 		cfg.fc_flags |= RTF_NONEXTHOP;
2484 #endif
2485 
2486 	ip6_route_add(&cfg, gfp_flags, NULL);
2487 }
2488 
2489 
2490 static struct fib6_info *addrconf_get_prefix_route(const struct in6_addr *pfx,
2491 						  int plen,
2492 						  const struct net_device *dev,
2493 						  u32 flags, u32 noflags,
2494 						  bool no_gw)
2495 {
2496 	struct fib6_node *fn;
2497 	struct fib6_info *rt = NULL;
2498 	struct fib6_table *table;
2499 	u32 tb_id = l3mdev_fib_table(dev) ? : RT6_TABLE_PREFIX;
2500 
2501 	table = fib6_get_table(dev_net(dev), tb_id);
2502 	if (!table)
2503 		return NULL;
2504 
2505 	rcu_read_lock();
2506 	fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0, true);
2507 	if (!fn)
2508 		goto out;
2509 
2510 	for_each_fib6_node_rt_rcu(fn) {
2511 		/* prefix routes only use builtin fib6_nh */
2512 		if (rt->nh)
2513 			continue;
2514 
2515 		if (rt->fib6_nh->fib_nh_dev->ifindex != dev->ifindex)
2516 			continue;
2517 		if (no_gw && rt->fib6_nh->fib_nh_gw_family)
2518 			continue;
2519 		if ((rt->fib6_flags & flags) != flags)
2520 			continue;
2521 		if ((rt->fib6_flags & noflags) != 0)
2522 			continue;
2523 		if (!fib6_info_hold_safe(rt))
2524 			continue;
2525 		break;
2526 	}
2527 out:
2528 	rcu_read_unlock();
2529 	return rt;
2530 }
2531 
2532 
2533 /* Create "default" multicast route to the interface */
2534 
2535 static void addrconf_add_mroute(struct net_device *dev)
2536 {
2537 	struct fib6_config cfg = {
2538 		.fc_table = l3mdev_fib_table(dev) ? : RT6_TABLE_LOCAL,
2539 		.fc_metric = IP6_RT_PRIO_ADDRCONF,
2540 		.fc_ifindex = dev->ifindex,
2541 		.fc_dst_len = 8,
2542 		.fc_flags = RTF_UP,
2543 		.fc_type = RTN_MULTICAST,
2544 		.fc_nlinfo.nl_net = dev_net(dev),
2545 		.fc_protocol = RTPROT_KERNEL,
2546 	};
2547 
2548 	ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);
2549 
2550 	ip6_route_add(&cfg, GFP_KERNEL, NULL);
2551 }
2552 
2553 static struct inet6_dev *addrconf_add_dev(struct net_device *dev)
2554 {
2555 	struct inet6_dev *idev;
2556 
2557 	ASSERT_RTNL();
2558 
2559 	idev = ipv6_find_idev(dev);
2560 	if (IS_ERR(idev))
2561 		return idev;
2562 
2563 	if (idev->cnf.disable_ipv6)
2564 		return ERR_PTR(-EACCES);
2565 
2566 	/* Add default multicast route */
2567 	if (!(dev->flags & IFF_LOOPBACK) && !netif_is_l3_master(dev))
2568 		addrconf_add_mroute(dev);
2569 
2570 	return idev;
2571 }
2572 
2573 static void manage_tempaddrs(struct inet6_dev *idev,
2574 			     struct inet6_ifaddr *ifp,
2575 			     __u32 valid_lft, __u32 prefered_lft,
2576 			     bool create, unsigned long now)
2577 {
2578 	u32 flags;
2579 	struct inet6_ifaddr *ift;
2580 
2581 	read_lock_bh(&idev->lock);
2582 	/* update all temporary addresses in the list */
2583 	list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
2584 		int age, max_valid, max_prefered;
2585 
2586 		if (ifp != ift->ifpub)
2587 			continue;
2588 
2589 		/* RFC 4941 section 3.3:
2590 		 * If a received option will extend the lifetime of a public
2591 		 * address, the lifetimes of temporary addresses should
2592 		 * be extended, subject to the overall constraint that no
2593 		 * temporary addresses should ever remain "valid" or "preferred"
2594 		 * for a time longer than (TEMP_VALID_LIFETIME) or
2595 		 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
2596 		 */
2597 		age = (now - ift->cstamp) / HZ;
2598 		max_valid = READ_ONCE(idev->cnf.temp_valid_lft) - age;
2599 		if (max_valid < 0)
2600 			max_valid = 0;
2601 
2602 		max_prefered = READ_ONCE(idev->cnf.temp_prefered_lft) -
2603 			       idev->desync_factor - age;
2604 		if (max_prefered < 0)
2605 			max_prefered = 0;
2606 
2607 		if (valid_lft > max_valid)
2608 			valid_lft = max_valid;
2609 
2610 		if (prefered_lft > max_prefered)
2611 			prefered_lft = max_prefered;
2612 
2613 		spin_lock(&ift->lock);
2614 		flags = ift->flags;
2615 		ift->valid_lft = valid_lft;
2616 		ift->prefered_lft = prefered_lft;
2617 		ift->tstamp = now;
2618 		if (prefered_lft > 0)
2619 			ift->flags &= ~IFA_F_DEPRECATED;
2620 
2621 		spin_unlock(&ift->lock);
2622 		if (!(flags&IFA_F_TENTATIVE))
2623 			ipv6_ifa_notify(0, ift);
2624 	}
2625 
2626 	/* Also create a temporary address if it's enabled but no temporary
2627 	 * address currently exists.
2628 	 * However, we get called with valid_lft == 0, prefered_lft == 0, create == false
2629 	 * as part of cleanup (ie. deleting the mngtmpaddr).
2630 	 * We don't want that to result in creating a new temporary ip address.
2631 	 */
2632 	if (list_empty(&idev->tempaddr_list) && (valid_lft || prefered_lft))
2633 		create = true;
2634 
2635 	if (create && READ_ONCE(idev->cnf.use_tempaddr) > 0) {
2636 		/* When a new public address is created as described
2637 		 * in [ADDRCONF], also create a new temporary address.
2638 		 */
2639 		read_unlock_bh(&idev->lock);
2640 		ipv6_create_tempaddr(ifp, false);
2641 	} else {
2642 		read_unlock_bh(&idev->lock);
2643 	}
2644 }
2645 
2646 static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
2647 {
2648 	return idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY ||
2649 	       idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
2650 }
2651 
2652 int addrconf_prefix_rcv_add_addr(struct net *net, struct net_device *dev,
2653 				 const struct prefix_info *pinfo,
2654 				 struct inet6_dev *in6_dev,
2655 				 const struct in6_addr *addr, int addr_type,
2656 				 u32 addr_flags, bool sllao, bool tokenized,
2657 				 __u32 valid_lft, u32 prefered_lft)
2658 {
2659 	struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
2660 	int create = 0, update_lft = 0;
2661 
2662 	if (!ifp && valid_lft) {
2663 		int max_addresses = READ_ONCE(in6_dev->cnf.max_addresses);
2664 		struct ifa6_config cfg = {
2665 			.pfx = addr,
2666 			.plen = pinfo->prefix_len,
2667 			.ifa_flags = addr_flags,
2668 			.valid_lft = valid_lft,
2669 			.preferred_lft = prefered_lft,
2670 			.scope = addr_type & IPV6_ADDR_SCOPE_MASK,
2671 			.ifa_proto = IFAPROT_KERNEL_RA
2672 		};
2673 
2674 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
2675 		if ((READ_ONCE(net->ipv6.devconf_all->optimistic_dad) ||
2676 		     READ_ONCE(in6_dev->cnf.optimistic_dad)) &&
2677 		    !net->ipv6.devconf_all->forwarding && sllao)
2678 			cfg.ifa_flags |= IFA_F_OPTIMISTIC;
2679 #endif
2680 
2681 		/* Do not allow to create too much of autoconfigured
2682 		 * addresses; this would be too easy way to crash kernel.
2683 		 */
2684 		if (!max_addresses ||
2685 		    ipv6_count_addresses(in6_dev) < max_addresses)
2686 			ifp = ipv6_add_addr(in6_dev, &cfg, false, NULL);
2687 
2688 		if (IS_ERR_OR_NULL(ifp))
2689 			return -1;
2690 
2691 		create = 1;
2692 		spin_lock_bh(&ifp->lock);
2693 		ifp->flags |= IFA_F_MANAGETEMPADDR;
2694 		ifp->cstamp = jiffies;
2695 		ifp->tokenized = tokenized;
2696 		spin_unlock_bh(&ifp->lock);
2697 		addrconf_dad_start(ifp);
2698 	}
2699 
2700 	if (ifp) {
2701 		u32 flags;
2702 		unsigned long now;
2703 		u32 stored_lft;
2704 
2705 		/* update lifetime (RFC2462 5.5.3 e) */
2706 		spin_lock_bh(&ifp->lock);
2707 		now = jiffies;
2708 		if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
2709 			stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
2710 		else
2711 			stored_lft = 0;
2712 
2713 		/* RFC4862 Section 5.5.3e:
2714 		 * "Note that the preferred lifetime of the
2715 		 *  corresponding address is always reset to
2716 		 *  the Preferred Lifetime in the received
2717 		 *  Prefix Information option, regardless of
2718 		 *  whether the valid lifetime is also reset or
2719 		 *  ignored."
2720 		 *
2721 		 * So we should always update prefered_lft here.
2722 		 */
2723 		update_lft = !create && stored_lft;
2724 
2725 		if (update_lft && !READ_ONCE(in6_dev->cnf.ra_honor_pio_life)) {
2726 			const u32 minimum_lft = min_t(u32,
2727 				stored_lft, MIN_VALID_LIFETIME);
2728 			valid_lft = max(valid_lft, minimum_lft);
2729 		}
2730 
2731 		if (update_lft) {
2732 			ifp->valid_lft = valid_lft;
2733 			ifp->prefered_lft = prefered_lft;
2734 			WRITE_ONCE(ifp->tstamp, now);
2735 			flags = ifp->flags;
2736 			ifp->flags &= ~IFA_F_DEPRECATED;
2737 			spin_unlock_bh(&ifp->lock);
2738 
2739 			if (!(flags&IFA_F_TENTATIVE))
2740 				ipv6_ifa_notify(0, ifp);
2741 		} else
2742 			spin_unlock_bh(&ifp->lock);
2743 
2744 		manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
2745 				 create, now);
2746 
2747 		in6_ifa_put(ifp);
2748 		addrconf_verify(net);
2749 	}
2750 
2751 	return 0;
2752 }
2753 EXPORT_SYMBOL_GPL(addrconf_prefix_rcv_add_addr);
2754 
2755 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
2756 {
2757 	struct prefix_info *pinfo;
2758 	struct fib6_table *table;
2759 	__u32 valid_lft;
2760 	__u32 prefered_lft;
2761 	int addr_type, err;
2762 	u32 addr_flags = 0;
2763 	struct inet6_dev *in6_dev;
2764 	struct net *net = dev_net(dev);
2765 	bool ignore_autoconf = false;
2766 
2767 	pinfo = (struct prefix_info *) opt;
2768 
2769 	if (len < sizeof(struct prefix_info)) {
2770 		netdev_dbg(dev, "addrconf: prefix option too short\n");
2771 		return;
2772 	}
2773 
2774 	/*
2775 	 *	Validation checks ([ADDRCONF], page 19)
2776 	 */
2777 
2778 	addr_type = ipv6_addr_type(&pinfo->prefix);
2779 
2780 	if (addr_type & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL))
2781 		return;
2782 
2783 	valid_lft = ntohl(pinfo->valid);
2784 	prefered_lft = ntohl(pinfo->prefered);
2785 
2786 	if (prefered_lft > valid_lft) {
2787 		net_warn_ratelimited("addrconf: prefix option has invalid lifetime\n");
2788 		return;
2789 	}
2790 
2791 	in6_dev = in6_dev_get(dev);
2792 
2793 	if (!in6_dev) {
2794 		net_dbg_ratelimited("addrconf: device %s not configured\n",
2795 				    dev->name);
2796 		return;
2797 	}
2798 
2799 	if (valid_lft != 0 && valid_lft < in6_dev->cnf.accept_ra_min_lft)
2800 		goto put;
2801 
2802 	/*
2803 	 *	Two things going on here:
2804 	 *	1) Add routes for on-link prefixes
2805 	 *	2) Configure prefixes with the auto flag set
2806 	 */
2807 
2808 	if (pinfo->onlink) {
2809 		struct fib6_info *rt;
2810 		unsigned long rt_expires;
2811 
2812 		/* Avoid arithmetic overflow. Really, we could
2813 		 * save rt_expires in seconds, likely valid_lft,
2814 		 * but it would require division in fib gc, that it
2815 		 * not good.
2816 		 */
2817 		if (HZ > USER_HZ)
2818 			rt_expires = addrconf_timeout_fixup(valid_lft, HZ);
2819 		else
2820 			rt_expires = addrconf_timeout_fixup(valid_lft, USER_HZ);
2821 
2822 		if (addrconf_finite_timeout(rt_expires))
2823 			rt_expires *= HZ;
2824 
2825 		rt = addrconf_get_prefix_route(&pinfo->prefix,
2826 					       pinfo->prefix_len,
2827 					       dev,
2828 					       RTF_ADDRCONF | RTF_PREFIX_RT,
2829 					       RTF_DEFAULT, true);
2830 
2831 		if (rt) {
2832 			/* Autoconf prefix route */
2833 			if (valid_lft == 0) {
2834 				ip6_del_rt(net, rt, false);
2835 				rt = NULL;
2836 			} else {
2837 				table = rt->fib6_table;
2838 				spin_lock_bh(&table->tb6_lock);
2839 
2840 				if (addrconf_finite_timeout(rt_expires)) {
2841 					/* not infinity */
2842 					fib6_set_expires(rt, jiffies + rt_expires);
2843 					fib6_add_gc_list(rt);
2844 				} else {
2845 					fib6_clean_expires(rt);
2846 					fib6_remove_gc_list(rt);
2847 				}
2848 
2849 				spin_unlock_bh(&table->tb6_lock);
2850 			}
2851 		} else if (valid_lft) {
2852 			clock_t expires = 0;
2853 			int flags = RTF_ADDRCONF | RTF_PREFIX_RT;
2854 			if (addrconf_finite_timeout(rt_expires)) {
2855 				/* not infinity */
2856 				flags |= RTF_EXPIRES;
2857 				expires = jiffies_to_clock_t(rt_expires);
2858 			}
2859 			addrconf_prefix_route(&pinfo->prefix, pinfo->prefix_len,
2860 					      0, dev, expires, flags,
2861 					      GFP_ATOMIC);
2862 		}
2863 		fib6_info_release(rt);
2864 	}
2865 
2866 	/* Try to figure out our local address for this prefix */
2867 
2868 	ignore_autoconf = READ_ONCE(in6_dev->cnf.ra_honor_pio_pflag) && pinfo->preferpd;
2869 	if (pinfo->autoconf && in6_dev->cnf.autoconf && !ignore_autoconf) {
2870 		struct in6_addr addr;
2871 		bool tokenized = false, dev_addr_generated = false;
2872 
2873 		if (pinfo->prefix_len == 64) {
2874 			memcpy(&addr, &pinfo->prefix, 8);
2875 
2876 			if (!ipv6_addr_any(&in6_dev->token)) {
2877 				read_lock_bh(&in6_dev->lock);
2878 				memcpy(addr.s6_addr + 8,
2879 				       in6_dev->token.s6_addr + 8, 8);
2880 				read_unlock_bh(&in6_dev->lock);
2881 				tokenized = true;
2882 			} else if (is_addr_mode_generate_stable(in6_dev) &&
2883 				   !ipv6_generate_stable_address(&addr, 0,
2884 								 in6_dev)) {
2885 				addr_flags |= IFA_F_STABLE_PRIVACY;
2886 				goto ok;
2887 			} else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
2888 				   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
2889 				goto put;
2890 			} else {
2891 				dev_addr_generated = true;
2892 			}
2893 			goto ok;
2894 		}
2895 		net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
2896 				    pinfo->prefix_len);
2897 		goto put;
2898 
2899 ok:
2900 		err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
2901 						   &addr, addr_type,
2902 						   addr_flags, sllao,
2903 						   tokenized, valid_lft,
2904 						   prefered_lft);
2905 		if (err)
2906 			goto put;
2907 
2908 		/* Ignore error case here because previous prefix add addr was
2909 		 * successful which will be notified.
2910 		 */
2911 		ndisc_ops_prefix_rcv_add_addr(net, dev, pinfo, in6_dev, &addr,
2912 					      addr_type, addr_flags, sllao,
2913 					      tokenized, valid_lft,
2914 					      prefered_lft,
2915 					      dev_addr_generated);
2916 	}
2917 	inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
2918 put:
2919 	in6_dev_put(in6_dev);
2920 }
2921 
2922 static int addrconf_set_sit_dstaddr(struct net *net, struct net_device *dev,
2923 		struct in6_ifreq *ireq)
2924 {
2925 	struct ip_tunnel_parm_kern p = { };
2926 	int err;
2927 
2928 	if (!(ipv6_addr_type(&ireq->ifr6_addr) & IPV6_ADDR_COMPATv4))
2929 		return -EADDRNOTAVAIL;
2930 
2931 	p.iph.daddr = ireq->ifr6_addr.s6_addr32[3];
2932 	p.iph.version = 4;
2933 	p.iph.ihl = 5;
2934 	p.iph.protocol = IPPROTO_IPV6;
2935 	p.iph.ttl = 64;
2936 
2937 	if (!dev->netdev_ops->ndo_tunnel_ctl)
2938 		return -EOPNOTSUPP;
2939 	err = dev->netdev_ops->ndo_tunnel_ctl(dev, &p, SIOCADDTUNNEL);
2940 	if (err)
2941 		return err;
2942 
2943 	dev = __dev_get_by_name(net, p.name);
2944 	if (!dev)
2945 		return -ENOBUFS;
2946 	return dev_open(dev, NULL);
2947 }
2948 
2949 /*
2950  *	Set destination address.
2951  *	Special case for SIT interfaces where we create a new "virtual"
2952  *	device.
2953  */
2954 int addrconf_set_dstaddr(struct net *net, void __user *arg)
2955 {
2956 	struct net_device *dev;
2957 	struct in6_ifreq ireq;
2958 	int err = -ENODEV;
2959 
2960 	if (!IS_ENABLED(CONFIG_IPV6_SIT))
2961 		return -ENODEV;
2962 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
2963 		return -EFAULT;
2964 
2965 	rtnl_lock();
2966 	dev = __dev_get_by_index(net, ireq.ifr6_ifindex);
2967 	if (dev && dev->type == ARPHRD_SIT)
2968 		err = addrconf_set_sit_dstaddr(net, dev, &ireq);
2969 	rtnl_unlock();
2970 	return err;
2971 }
2972 
2973 static int ipv6_mc_config(struct sock *sk, bool join,
2974 			  const struct in6_addr *addr, int ifindex)
2975 {
2976 	int ret;
2977 
2978 	ASSERT_RTNL();
2979 
2980 	lock_sock(sk);
2981 	if (join)
2982 		ret = ipv6_sock_mc_join(sk, ifindex, addr);
2983 	else
2984 		ret = ipv6_sock_mc_drop(sk, ifindex, addr);
2985 	release_sock(sk);
2986 
2987 	return ret;
2988 }
2989 
2990 /*
2991  *	Manual configuration of address on an interface
2992  */
2993 static int inet6_addr_add(struct net *net, int ifindex,
2994 			  struct ifa6_config *cfg,
2995 			  struct netlink_ext_ack *extack)
2996 {
2997 	struct inet6_ifaddr *ifp;
2998 	struct inet6_dev *idev;
2999 	struct net_device *dev;
3000 	unsigned long timeout;
3001 	clock_t expires;
3002 	u32 flags;
3003 
3004 	ASSERT_RTNL();
3005 
3006 	if (cfg->plen > 128) {
3007 		NL_SET_ERR_MSG_MOD(extack, "Invalid prefix length");
3008 		return -EINVAL;
3009 	}
3010 
3011 	/* check the lifetime */
3012 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft) {
3013 		NL_SET_ERR_MSG_MOD(extack, "address lifetime invalid");
3014 		return -EINVAL;
3015 	}
3016 
3017 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR && cfg->plen != 64) {
3018 		NL_SET_ERR_MSG_MOD(extack, "address with \"mngtmpaddr\" flag must have a prefix length of 64");
3019 		return -EINVAL;
3020 	}
3021 
3022 	dev = __dev_get_by_index(net, ifindex);
3023 	if (!dev)
3024 		return -ENODEV;
3025 
3026 	idev = addrconf_add_dev(dev);
3027 	if (IS_ERR(idev)) {
3028 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
3029 		return PTR_ERR(idev);
3030 	}
3031 
3032 	if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
3033 		int ret = ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3034 					 true, cfg->pfx, ifindex);
3035 
3036 		if (ret < 0) {
3037 			NL_SET_ERR_MSG_MOD(extack, "Multicast auto join failed");
3038 			return ret;
3039 		}
3040 	}
3041 
3042 	cfg->scope = ipv6_addr_scope(cfg->pfx);
3043 
3044 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
3045 	if (addrconf_finite_timeout(timeout)) {
3046 		expires = jiffies_to_clock_t(timeout * HZ);
3047 		cfg->valid_lft = timeout;
3048 		flags = RTF_EXPIRES;
3049 	} else {
3050 		expires = 0;
3051 		flags = 0;
3052 		cfg->ifa_flags |= IFA_F_PERMANENT;
3053 	}
3054 
3055 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
3056 	if (addrconf_finite_timeout(timeout)) {
3057 		if (timeout == 0)
3058 			cfg->ifa_flags |= IFA_F_DEPRECATED;
3059 		cfg->preferred_lft = timeout;
3060 	}
3061 
3062 	ifp = ipv6_add_addr(idev, cfg, true, extack);
3063 	if (!IS_ERR(ifp)) {
3064 		if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
3065 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3066 					      ifp->rt_priority, dev, expires,
3067 					      flags, GFP_KERNEL);
3068 		}
3069 
3070 		/* Send a netlink notification if DAD is enabled and
3071 		 * optimistic flag is not set
3072 		 */
3073 		if (!(ifp->flags & (IFA_F_OPTIMISTIC | IFA_F_NODAD)))
3074 			ipv6_ifa_notify(0, ifp);
3075 		/*
3076 		 * Note that section 3.1 of RFC 4429 indicates
3077 		 * that the Optimistic flag should not be set for
3078 		 * manually configured addresses
3079 		 */
3080 		addrconf_dad_start(ifp);
3081 		if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR)
3082 			manage_tempaddrs(idev, ifp, cfg->valid_lft,
3083 					 cfg->preferred_lft, true, jiffies);
3084 		in6_ifa_put(ifp);
3085 		addrconf_verify_rtnl(net);
3086 		return 0;
3087 	} else if (cfg->ifa_flags & IFA_F_MCAUTOJOIN) {
3088 		ipv6_mc_config(net->ipv6.mc_autojoin_sk, false,
3089 			       cfg->pfx, ifindex);
3090 	}
3091 
3092 	return PTR_ERR(ifp);
3093 }
3094 
3095 static int inet6_addr_del(struct net *net, int ifindex, u32 ifa_flags,
3096 			  const struct in6_addr *pfx, unsigned int plen,
3097 			  struct netlink_ext_ack *extack)
3098 {
3099 	struct inet6_ifaddr *ifp;
3100 	struct inet6_dev *idev;
3101 	struct net_device *dev;
3102 
3103 	if (plen > 128) {
3104 		NL_SET_ERR_MSG_MOD(extack, "Invalid prefix length");
3105 		return -EINVAL;
3106 	}
3107 
3108 	dev = __dev_get_by_index(net, ifindex);
3109 	if (!dev) {
3110 		NL_SET_ERR_MSG_MOD(extack, "Unable to find the interface");
3111 		return -ENODEV;
3112 	}
3113 
3114 	idev = __in6_dev_get(dev);
3115 	if (!idev) {
3116 		NL_SET_ERR_MSG_MOD(extack, "IPv6 is disabled on this device");
3117 		return -ENXIO;
3118 	}
3119 
3120 	read_lock_bh(&idev->lock);
3121 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
3122 		if (ifp->prefix_len == plen &&
3123 		    ipv6_addr_equal(pfx, &ifp->addr)) {
3124 			in6_ifa_hold(ifp);
3125 			read_unlock_bh(&idev->lock);
3126 
3127 			if (!(ifp->flags & IFA_F_TEMPORARY) &&
3128 			    (ifa_flags & IFA_F_MANAGETEMPADDR))
3129 				manage_tempaddrs(idev, ifp, 0, 0, false,
3130 						 jiffies);
3131 			ipv6_del_addr(ifp);
3132 			addrconf_verify_rtnl(net);
3133 			if (ipv6_addr_is_multicast(pfx)) {
3134 				ipv6_mc_config(net->ipv6.mc_autojoin_sk,
3135 					       false, pfx, dev->ifindex);
3136 			}
3137 			return 0;
3138 		}
3139 	}
3140 	read_unlock_bh(&idev->lock);
3141 
3142 	NL_SET_ERR_MSG_MOD(extack, "address not found");
3143 	return -EADDRNOTAVAIL;
3144 }
3145 
3146 
3147 int addrconf_add_ifaddr(struct net *net, void __user *arg)
3148 {
3149 	struct ifa6_config cfg = {
3150 		.ifa_flags = IFA_F_PERMANENT,
3151 		.preferred_lft = INFINITY_LIFE_TIME,
3152 		.valid_lft = INFINITY_LIFE_TIME,
3153 	};
3154 	struct in6_ifreq ireq;
3155 	int err;
3156 
3157 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3158 		return -EPERM;
3159 
3160 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3161 		return -EFAULT;
3162 
3163 	cfg.pfx = &ireq.ifr6_addr;
3164 	cfg.plen = ireq.ifr6_prefixlen;
3165 
3166 	rtnl_lock();
3167 	err = inet6_addr_add(net, ireq.ifr6_ifindex, &cfg, NULL);
3168 	rtnl_unlock();
3169 	return err;
3170 }
3171 
3172 int addrconf_del_ifaddr(struct net *net, void __user *arg)
3173 {
3174 	struct in6_ifreq ireq;
3175 	int err;
3176 
3177 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3178 		return -EPERM;
3179 
3180 	if (copy_from_user(&ireq, arg, sizeof(struct in6_ifreq)))
3181 		return -EFAULT;
3182 
3183 	rtnl_lock();
3184 	err = inet6_addr_del(net, ireq.ifr6_ifindex, 0, &ireq.ifr6_addr,
3185 			     ireq.ifr6_prefixlen, NULL);
3186 	rtnl_unlock();
3187 	return err;
3188 }
3189 
3190 static void add_addr(struct inet6_dev *idev, const struct in6_addr *addr,
3191 		     int plen, int scope, u8 proto)
3192 {
3193 	struct inet6_ifaddr *ifp;
3194 	struct ifa6_config cfg = {
3195 		.pfx = addr,
3196 		.plen = plen,
3197 		.ifa_flags = IFA_F_PERMANENT,
3198 		.valid_lft = INFINITY_LIFE_TIME,
3199 		.preferred_lft = INFINITY_LIFE_TIME,
3200 		.scope = scope,
3201 		.ifa_proto = proto
3202 	};
3203 
3204 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3205 	if (!IS_ERR(ifp)) {
3206 		spin_lock_bh(&ifp->lock);
3207 		ifp->flags &= ~IFA_F_TENTATIVE;
3208 		spin_unlock_bh(&ifp->lock);
3209 		rt_genid_bump_ipv6(dev_net(idev->dev));
3210 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
3211 		in6_ifa_put(ifp);
3212 	}
3213 }
3214 
3215 #if IS_ENABLED(CONFIG_IPV6_SIT) || IS_ENABLED(CONFIG_NET_IPGRE) || IS_ENABLED(CONFIG_IPV6_GRE)
3216 static void add_v4_addrs(struct inet6_dev *idev)
3217 {
3218 	struct in6_addr addr;
3219 	struct net_device *dev;
3220 	struct net *net = dev_net(idev->dev);
3221 	int scope, plen, offset = 0;
3222 	u32 pflags = 0;
3223 
3224 	ASSERT_RTNL();
3225 
3226 	memset(&addr, 0, sizeof(struct in6_addr));
3227 	/* in case of IP6GRE the dev_addr is an IPv6 and therefore we use only the last 4 bytes */
3228 	if (idev->dev->addr_len == sizeof(struct in6_addr))
3229 		offset = sizeof(struct in6_addr) - 4;
3230 	memcpy(&addr.s6_addr32[3], idev->dev->dev_addr + offset, 4);
3231 
3232 	if (!(idev->dev->flags & IFF_POINTOPOINT) && idev->dev->type == ARPHRD_SIT) {
3233 		scope = IPV6_ADDR_COMPATv4;
3234 		plen = 96;
3235 		pflags |= RTF_NONEXTHOP;
3236 	} else {
3237 		if (idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_NONE)
3238 			return;
3239 
3240 		addr.s6_addr32[0] = htonl(0xfe800000);
3241 		scope = IFA_LINK;
3242 		plen = 64;
3243 	}
3244 
3245 	if (addr.s6_addr32[3]) {
3246 		add_addr(idev, &addr, plen, scope, IFAPROT_UNSPEC);
3247 		addrconf_prefix_route(&addr, plen, 0, idev->dev, 0, pflags,
3248 				      GFP_KERNEL);
3249 		return;
3250 	}
3251 
3252 	for_each_netdev(net, dev) {
3253 		struct in_device *in_dev = __in_dev_get_rtnl(dev);
3254 		if (in_dev && (dev->flags & IFF_UP)) {
3255 			struct in_ifaddr *ifa;
3256 			int flag = scope;
3257 
3258 			in_dev_for_each_ifa_rtnl(ifa, in_dev) {
3259 				addr.s6_addr32[3] = ifa->ifa_local;
3260 
3261 				if (ifa->ifa_scope == RT_SCOPE_LINK)
3262 					continue;
3263 				if (ifa->ifa_scope >= RT_SCOPE_HOST) {
3264 					if (idev->dev->flags&IFF_POINTOPOINT)
3265 						continue;
3266 					flag |= IFA_HOST;
3267 				}
3268 
3269 				add_addr(idev, &addr, plen, flag,
3270 					 IFAPROT_UNSPEC);
3271 				addrconf_prefix_route(&addr, plen, 0, idev->dev,
3272 						      0, pflags, GFP_KERNEL);
3273 			}
3274 		}
3275 	}
3276 }
3277 #endif
3278 
3279 static void init_loopback(struct net_device *dev)
3280 {
3281 	struct inet6_dev  *idev;
3282 
3283 	/* ::1 */
3284 
3285 	ASSERT_RTNL();
3286 
3287 	idev = ipv6_find_idev(dev);
3288 	if (IS_ERR(idev)) {
3289 		pr_debug("%s: add_dev failed\n", __func__);
3290 		return;
3291 	}
3292 
3293 	add_addr(idev, &in6addr_loopback, 128, IFA_HOST, IFAPROT_KERNEL_LO);
3294 }
3295 
3296 void addrconf_add_linklocal(struct inet6_dev *idev,
3297 			    const struct in6_addr *addr, u32 flags)
3298 {
3299 	struct ifa6_config cfg = {
3300 		.pfx = addr,
3301 		.plen = 64,
3302 		.ifa_flags = flags | IFA_F_PERMANENT,
3303 		.valid_lft = INFINITY_LIFE_TIME,
3304 		.preferred_lft = INFINITY_LIFE_TIME,
3305 		.scope = IFA_LINK,
3306 		.ifa_proto = IFAPROT_KERNEL_LL
3307 	};
3308 	struct inet6_ifaddr *ifp;
3309 
3310 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
3311 	if ((READ_ONCE(dev_net(idev->dev)->ipv6.devconf_all->optimistic_dad) ||
3312 	     READ_ONCE(idev->cnf.optimistic_dad)) &&
3313 	    !dev_net(idev->dev)->ipv6.devconf_all->forwarding)
3314 		cfg.ifa_flags |= IFA_F_OPTIMISTIC;
3315 #endif
3316 
3317 	ifp = ipv6_add_addr(idev, &cfg, true, NULL);
3318 	if (!IS_ERR(ifp)) {
3319 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len, 0, idev->dev,
3320 				      0, 0, GFP_ATOMIC);
3321 		addrconf_dad_start(ifp);
3322 		in6_ifa_put(ifp);
3323 	}
3324 }
3325 EXPORT_SYMBOL_GPL(addrconf_add_linklocal);
3326 
3327 static bool ipv6_reserved_interfaceid(struct in6_addr address)
3328 {
3329 	if ((address.s6_addr32[2] | address.s6_addr32[3]) == 0)
3330 		return true;
3331 
3332 	if (address.s6_addr32[2] == htonl(0x02005eff) &&
3333 	    ((address.s6_addr32[3] & htonl(0xfe000000)) == htonl(0xfe000000)))
3334 		return true;
3335 
3336 	if (address.s6_addr32[2] == htonl(0xfdffffff) &&
3337 	    ((address.s6_addr32[3] & htonl(0xffffff80)) == htonl(0xffffff80)))
3338 		return true;
3339 
3340 	return false;
3341 }
3342 
3343 static int ipv6_generate_stable_address(struct in6_addr *address,
3344 					u8 dad_count,
3345 					const struct inet6_dev *idev)
3346 {
3347 	static DEFINE_SPINLOCK(lock);
3348 	static __u32 digest[SHA1_DIGEST_WORDS];
3349 	static __u32 workspace[SHA1_WORKSPACE_WORDS];
3350 
3351 	static union {
3352 		char __data[SHA1_BLOCK_SIZE];
3353 		struct {
3354 			struct in6_addr secret;
3355 			__be32 prefix[2];
3356 			unsigned char hwaddr[MAX_ADDR_LEN];
3357 			u8 dad_count;
3358 		} __packed;
3359 	} data;
3360 
3361 	struct in6_addr secret;
3362 	struct in6_addr temp;
3363 	struct net *net = dev_net(idev->dev);
3364 
3365 	BUILD_BUG_ON(sizeof(data.__data) != sizeof(data));
3366 
3367 	if (idev->cnf.stable_secret.initialized)
3368 		secret = idev->cnf.stable_secret.secret;
3369 	else if (net->ipv6.devconf_dflt->stable_secret.initialized)
3370 		secret = net->ipv6.devconf_dflt->stable_secret.secret;
3371 	else
3372 		return -1;
3373 
3374 retry:
3375 	spin_lock_bh(&lock);
3376 
3377 	sha1_init(digest);
3378 	memset(&data, 0, sizeof(data));
3379 	memset(workspace, 0, sizeof(workspace));
3380 	memcpy(data.hwaddr, idev->dev->perm_addr, idev->dev->addr_len);
3381 	data.prefix[0] = address->s6_addr32[0];
3382 	data.prefix[1] = address->s6_addr32[1];
3383 	data.secret = secret;
3384 	data.dad_count = dad_count;
3385 
3386 	sha1_transform(digest, data.__data, workspace);
3387 
3388 	temp = *address;
3389 	temp.s6_addr32[2] = (__force __be32)digest[0];
3390 	temp.s6_addr32[3] = (__force __be32)digest[1];
3391 
3392 	spin_unlock_bh(&lock);
3393 
3394 	if (ipv6_reserved_interfaceid(temp)) {
3395 		dad_count++;
3396 		if (dad_count > dev_net(idev->dev)->ipv6.sysctl.idgen_retries)
3397 			return -1;
3398 		goto retry;
3399 	}
3400 
3401 	*address = temp;
3402 	return 0;
3403 }
3404 
3405 static void ipv6_gen_mode_random_init(struct inet6_dev *idev)
3406 {
3407 	struct ipv6_stable_secret *s = &idev->cnf.stable_secret;
3408 
3409 	if (s->initialized)
3410 		return;
3411 	s = &idev->cnf.stable_secret;
3412 	get_random_bytes(&s->secret, sizeof(s->secret));
3413 	s->initialized = true;
3414 }
3415 
3416 static void addrconf_addr_gen(struct inet6_dev *idev, bool prefix_route)
3417 {
3418 	struct in6_addr addr;
3419 
3420 	/* no link local addresses on L3 master devices */
3421 	if (netif_is_l3_master(idev->dev))
3422 		return;
3423 
3424 	/* no link local addresses on devices flagged as slaves */
3425 	if (idev->dev->priv_flags & IFF_NO_ADDRCONF)
3426 		return;
3427 
3428 	ipv6_addr_set(&addr, htonl(0xFE800000), 0, 0, 0);
3429 
3430 	switch (idev->cnf.addr_gen_mode) {
3431 	case IN6_ADDR_GEN_MODE_RANDOM:
3432 		ipv6_gen_mode_random_init(idev);
3433 		fallthrough;
3434 	case IN6_ADDR_GEN_MODE_STABLE_PRIVACY:
3435 		if (!ipv6_generate_stable_address(&addr, 0, idev))
3436 			addrconf_add_linklocal(idev, &addr,
3437 					       IFA_F_STABLE_PRIVACY);
3438 		else if (prefix_route)
3439 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3440 					      0, 0, GFP_KERNEL);
3441 		break;
3442 	case IN6_ADDR_GEN_MODE_EUI64:
3443 		/* addrconf_add_linklocal also adds a prefix_route and we
3444 		 * only need to care about prefix routes if ipv6_generate_eui64
3445 		 * couldn't generate one.
3446 		 */
3447 		if (ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) == 0)
3448 			addrconf_add_linklocal(idev, &addr, 0);
3449 		else if (prefix_route)
3450 			addrconf_prefix_route(&addr, 64, 0, idev->dev,
3451 					      0, 0, GFP_KERNEL);
3452 		break;
3453 	case IN6_ADDR_GEN_MODE_NONE:
3454 	default:
3455 		/* will not add any link local address */
3456 		break;
3457 	}
3458 }
3459 
3460 static void addrconf_dev_config(struct net_device *dev)
3461 {
3462 	struct inet6_dev *idev;
3463 
3464 	ASSERT_RTNL();
3465 
3466 	if ((dev->type != ARPHRD_ETHER) &&
3467 	    (dev->type != ARPHRD_FDDI) &&
3468 	    (dev->type != ARPHRD_ARCNET) &&
3469 	    (dev->type != ARPHRD_INFINIBAND) &&
3470 	    (dev->type != ARPHRD_IEEE1394) &&
3471 	    (dev->type != ARPHRD_TUNNEL6) &&
3472 	    (dev->type != ARPHRD_6LOWPAN) &&
3473 	    (dev->type != ARPHRD_TUNNEL) &&
3474 	    (dev->type != ARPHRD_NONE) &&
3475 	    (dev->type != ARPHRD_RAWIP)) {
3476 		/* Alas, we support only Ethernet autoconfiguration. */
3477 		idev = __in6_dev_get(dev);
3478 		if (!IS_ERR_OR_NULL(idev) && dev->flags & IFF_UP &&
3479 		    dev->flags & IFF_MULTICAST)
3480 			ipv6_mc_up(idev);
3481 		return;
3482 	}
3483 
3484 	idev = addrconf_add_dev(dev);
3485 	if (IS_ERR(idev))
3486 		return;
3487 
3488 	/* this device type has no EUI support */
3489 	if (dev->type == ARPHRD_NONE &&
3490 	    idev->cnf.addr_gen_mode == IN6_ADDR_GEN_MODE_EUI64)
3491 		WRITE_ONCE(idev->cnf.addr_gen_mode,
3492 			   IN6_ADDR_GEN_MODE_RANDOM);
3493 
3494 	addrconf_addr_gen(idev, false);
3495 }
3496 
3497 #if IS_ENABLED(CONFIG_IPV6_SIT)
3498 static void addrconf_sit_config(struct net_device *dev)
3499 {
3500 	struct inet6_dev *idev;
3501 
3502 	ASSERT_RTNL();
3503 
3504 	/*
3505 	 * Configure the tunnel with one of our IPv4
3506 	 * addresses... we should configure all of
3507 	 * our v4 addrs in the tunnel
3508 	 */
3509 
3510 	idev = ipv6_find_idev(dev);
3511 	if (IS_ERR(idev)) {
3512 		pr_debug("%s: add_dev failed\n", __func__);
3513 		return;
3514 	}
3515 
3516 	if (dev->priv_flags & IFF_ISATAP) {
3517 		addrconf_addr_gen(idev, false);
3518 		return;
3519 	}
3520 
3521 	add_v4_addrs(idev);
3522 
3523 	if (dev->flags&IFF_POINTOPOINT)
3524 		addrconf_add_mroute(dev);
3525 }
3526 #endif
3527 
3528 #if IS_ENABLED(CONFIG_NET_IPGRE) || IS_ENABLED(CONFIG_IPV6_GRE)
3529 static void addrconf_gre_config(struct net_device *dev)
3530 {
3531 	struct inet6_dev *idev;
3532 
3533 	ASSERT_RTNL();
3534 
3535 	idev = ipv6_find_idev(dev);
3536 	if (IS_ERR(idev)) {
3537 		pr_debug("%s: add_dev failed\n", __func__);
3538 		return;
3539 	}
3540 
3541 	if (dev->type == ARPHRD_ETHER) {
3542 		addrconf_addr_gen(idev, true);
3543 		return;
3544 	}
3545 
3546 	add_v4_addrs(idev);
3547 
3548 	if (dev->flags & IFF_POINTOPOINT)
3549 		addrconf_add_mroute(dev);
3550 }
3551 #endif
3552 
3553 static void addrconf_init_auto_addrs(struct net_device *dev)
3554 {
3555 	switch (dev->type) {
3556 #if IS_ENABLED(CONFIG_IPV6_SIT)
3557 	case ARPHRD_SIT:
3558 		addrconf_sit_config(dev);
3559 		break;
3560 #endif
3561 #if IS_ENABLED(CONFIG_NET_IPGRE) || IS_ENABLED(CONFIG_IPV6_GRE)
3562 	case ARPHRD_IP6GRE:
3563 	case ARPHRD_IPGRE:
3564 		addrconf_gre_config(dev);
3565 		break;
3566 #endif
3567 	case ARPHRD_LOOPBACK:
3568 		init_loopback(dev);
3569 		break;
3570 
3571 	default:
3572 		addrconf_dev_config(dev);
3573 		break;
3574 	}
3575 }
3576 
3577 static int fixup_permanent_addr(struct net *net,
3578 				struct inet6_dev *idev,
3579 				struct inet6_ifaddr *ifp)
3580 {
3581 	/* !fib6_node means the host route was removed from the
3582 	 * FIB, for example, if 'lo' device is taken down. In that
3583 	 * case regenerate the host route.
3584 	 */
3585 	if (!ifp->rt || !ifp->rt->fib6_node) {
3586 		struct fib6_info *f6i, *prev;
3587 
3588 		f6i = addrconf_f6i_alloc(net, idev, &ifp->addr, false,
3589 					 GFP_ATOMIC, NULL);
3590 		if (IS_ERR(f6i))
3591 			return PTR_ERR(f6i);
3592 
3593 		/* ifp->rt can be accessed outside of rtnl */
3594 		spin_lock(&ifp->lock);
3595 		prev = ifp->rt;
3596 		ifp->rt = f6i;
3597 		spin_unlock(&ifp->lock);
3598 
3599 		fib6_info_release(prev);
3600 	}
3601 
3602 	if (!(ifp->flags & IFA_F_NOPREFIXROUTE)) {
3603 		addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
3604 				      ifp->rt_priority, idev->dev, 0, 0,
3605 				      GFP_ATOMIC);
3606 	}
3607 
3608 	if (ifp->state == INET6_IFADDR_STATE_PREDAD)
3609 		addrconf_dad_start(ifp);
3610 
3611 	return 0;
3612 }
3613 
3614 static void addrconf_permanent_addr(struct net *net, struct net_device *dev)
3615 {
3616 	struct inet6_ifaddr *ifp, *tmp;
3617 	struct inet6_dev *idev;
3618 
3619 	idev = __in6_dev_get(dev);
3620 	if (!idev)
3621 		return;
3622 
3623 	write_lock_bh(&idev->lock);
3624 
3625 	list_for_each_entry_safe(ifp, tmp, &idev->addr_list, if_list) {
3626 		if ((ifp->flags & IFA_F_PERMANENT) &&
3627 		    fixup_permanent_addr(net, idev, ifp) < 0) {
3628 			write_unlock_bh(&idev->lock);
3629 			in6_ifa_hold(ifp);
3630 			ipv6_del_addr(ifp);
3631 			write_lock_bh(&idev->lock);
3632 
3633 			net_info_ratelimited("%s: Failed to add prefix route for address %pI6c; dropping\n",
3634 					     idev->dev->name, &ifp->addr);
3635 		}
3636 	}
3637 
3638 	write_unlock_bh(&idev->lock);
3639 }
3640 
3641 static int addrconf_notify(struct notifier_block *this, unsigned long event,
3642 			   void *ptr)
3643 {
3644 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
3645 	struct netdev_notifier_change_info *change_info;
3646 	struct netdev_notifier_changeupper_info *info;
3647 	struct inet6_dev *idev = __in6_dev_get(dev);
3648 	struct net *net = dev_net(dev);
3649 	int run_pending = 0;
3650 	int err;
3651 
3652 	switch (event) {
3653 	case NETDEV_REGISTER:
3654 		if (!idev && dev->mtu >= IPV6_MIN_MTU) {
3655 			idev = ipv6_add_dev(dev);
3656 			if (IS_ERR(idev))
3657 				return notifier_from_errno(PTR_ERR(idev));
3658 		}
3659 		break;
3660 
3661 	case NETDEV_CHANGEMTU:
3662 		/* if MTU under IPV6_MIN_MTU stop IPv6 on this interface. */
3663 		if (dev->mtu < IPV6_MIN_MTU) {
3664 			addrconf_ifdown(dev, dev != net->loopback_dev);
3665 			break;
3666 		}
3667 
3668 		if (idev) {
3669 			rt6_mtu_change(dev, dev->mtu);
3670 			WRITE_ONCE(idev->cnf.mtu6, dev->mtu);
3671 			break;
3672 		}
3673 
3674 		/* allocate new idev */
3675 		idev = ipv6_add_dev(dev);
3676 		if (IS_ERR(idev))
3677 			break;
3678 
3679 		/* device is still not ready */
3680 		if (!(idev->if_flags & IF_READY))
3681 			break;
3682 
3683 		run_pending = 1;
3684 		fallthrough;
3685 	case NETDEV_UP:
3686 	case NETDEV_CHANGE:
3687 		if (idev && idev->cnf.disable_ipv6)
3688 			break;
3689 
3690 		if (dev->priv_flags & IFF_NO_ADDRCONF) {
3691 			if (event == NETDEV_UP && !IS_ERR_OR_NULL(idev) &&
3692 			    dev->flags & IFF_UP && dev->flags & IFF_MULTICAST)
3693 				ipv6_mc_up(idev);
3694 			break;
3695 		}
3696 
3697 		if (event == NETDEV_UP) {
3698 			/* restore routes for permanent addresses */
3699 			addrconf_permanent_addr(net, dev);
3700 
3701 			if (!addrconf_link_ready(dev)) {
3702 				/* device is not ready yet. */
3703 				pr_debug("ADDRCONF(NETDEV_UP): %s: link is not ready\n",
3704 					 dev->name);
3705 				break;
3706 			}
3707 
3708 			if (!idev && dev->mtu >= IPV6_MIN_MTU)
3709 				idev = ipv6_add_dev(dev);
3710 
3711 			if (!IS_ERR_OR_NULL(idev)) {
3712 				idev->if_flags |= IF_READY;
3713 				run_pending = 1;
3714 			}
3715 		} else if (event == NETDEV_CHANGE) {
3716 			if (!addrconf_link_ready(dev)) {
3717 				/* device is still not ready. */
3718 				rt6_sync_down_dev(dev, event);
3719 				break;
3720 			}
3721 
3722 			if (!IS_ERR_OR_NULL(idev)) {
3723 				if (idev->if_flags & IF_READY) {
3724 					/* device is already configured -
3725 					 * but resend MLD reports, we might
3726 					 * have roamed and need to update
3727 					 * multicast snooping switches
3728 					 */
3729 					ipv6_mc_up(idev);
3730 					change_info = ptr;
3731 					if (change_info->flags_changed & IFF_NOARP)
3732 						addrconf_dad_run(idev, true);
3733 					rt6_sync_up(dev, RTNH_F_LINKDOWN);
3734 					break;
3735 				}
3736 				idev->if_flags |= IF_READY;
3737 			}
3738 
3739 			pr_debug("ADDRCONF(NETDEV_CHANGE): %s: link becomes ready\n",
3740 				 dev->name);
3741 
3742 			run_pending = 1;
3743 		}
3744 
3745 		addrconf_init_auto_addrs(dev);
3746 
3747 		if (!IS_ERR_OR_NULL(idev)) {
3748 			if (run_pending)
3749 				addrconf_dad_run(idev, false);
3750 
3751 			/* Device has an address by now */
3752 			rt6_sync_up(dev, RTNH_F_DEAD);
3753 
3754 			/*
3755 			 * If the MTU changed during the interface down,
3756 			 * when the interface up, the changed MTU must be
3757 			 * reflected in the idev as well as routers.
3758 			 */
3759 			if (idev->cnf.mtu6 != dev->mtu &&
3760 			    dev->mtu >= IPV6_MIN_MTU) {
3761 				rt6_mtu_change(dev, dev->mtu);
3762 				WRITE_ONCE(idev->cnf.mtu6, dev->mtu);
3763 			}
3764 			WRITE_ONCE(idev->tstamp, jiffies);
3765 			inet6_ifinfo_notify(RTM_NEWLINK, idev);
3766 
3767 			/*
3768 			 * If the changed mtu during down is lower than
3769 			 * IPV6_MIN_MTU stop IPv6 on this interface.
3770 			 */
3771 			if (dev->mtu < IPV6_MIN_MTU)
3772 				addrconf_ifdown(dev, dev != net->loopback_dev);
3773 		}
3774 		break;
3775 
3776 	case NETDEV_DOWN:
3777 	case NETDEV_UNREGISTER:
3778 		/*
3779 		 *	Remove all addresses from this interface.
3780 		 */
3781 		addrconf_ifdown(dev, event != NETDEV_DOWN);
3782 		break;
3783 
3784 	case NETDEV_CHANGENAME:
3785 		if (idev) {
3786 			snmp6_unregister_dev(idev);
3787 			addrconf_sysctl_unregister(idev);
3788 			err = addrconf_sysctl_register(idev);
3789 			if (err)
3790 				return notifier_from_errno(err);
3791 			err = snmp6_register_dev(idev);
3792 			if (err) {
3793 				addrconf_sysctl_unregister(idev);
3794 				return notifier_from_errno(err);
3795 			}
3796 		}
3797 		break;
3798 
3799 	case NETDEV_PRE_TYPE_CHANGE:
3800 	case NETDEV_POST_TYPE_CHANGE:
3801 		if (idev)
3802 			addrconf_type_change(dev, event);
3803 		break;
3804 
3805 	case NETDEV_CHANGEUPPER:
3806 		info = ptr;
3807 
3808 		/* flush all routes if dev is linked to or unlinked from
3809 		 * an L3 master device (e.g., VRF)
3810 		 */
3811 		if (info->upper_dev && netif_is_l3_master(info->upper_dev))
3812 			addrconf_ifdown(dev, false);
3813 	}
3814 
3815 	return NOTIFY_OK;
3816 }
3817 
3818 /*
3819  *	addrconf module should be notified of a device going up
3820  */
3821 static struct notifier_block ipv6_dev_notf = {
3822 	.notifier_call = addrconf_notify,
3823 	.priority = ADDRCONF_NOTIFY_PRIORITY,
3824 };
3825 
3826 static void addrconf_type_change(struct net_device *dev, unsigned long event)
3827 {
3828 	struct inet6_dev *idev;
3829 	ASSERT_RTNL();
3830 
3831 	idev = __in6_dev_get(dev);
3832 
3833 	if (event == NETDEV_POST_TYPE_CHANGE)
3834 		ipv6_mc_remap(idev);
3835 	else if (event == NETDEV_PRE_TYPE_CHANGE)
3836 		ipv6_mc_unmap(idev);
3837 }
3838 
3839 static bool addr_is_local(const struct in6_addr *addr)
3840 {
3841 	return ipv6_addr_type(addr) &
3842 		(IPV6_ADDR_LINKLOCAL | IPV6_ADDR_LOOPBACK);
3843 }
3844 
3845 static int addrconf_ifdown(struct net_device *dev, bool unregister)
3846 {
3847 	unsigned long event = unregister ? NETDEV_UNREGISTER : NETDEV_DOWN;
3848 	struct net *net = dev_net(dev);
3849 	struct inet6_dev *idev;
3850 	struct inet6_ifaddr *ifa;
3851 	LIST_HEAD(tmp_addr_list);
3852 	bool keep_addr = false;
3853 	bool was_ready;
3854 	int state, i;
3855 
3856 	ASSERT_RTNL();
3857 
3858 	rt6_disable_ip(dev, event);
3859 
3860 	idev = __in6_dev_get(dev);
3861 	if (!idev)
3862 		return -ENODEV;
3863 
3864 	/*
3865 	 * Step 1: remove reference to ipv6 device from parent device.
3866 	 *	   Do not dev_put!
3867 	 */
3868 	if (unregister) {
3869 		idev->dead = 1;
3870 
3871 		/* protected by rtnl_lock */
3872 		RCU_INIT_POINTER(dev->ip6_ptr, NULL);
3873 
3874 		/* Step 1.5: remove snmp6 entry */
3875 		snmp6_unregister_dev(idev);
3876 
3877 	}
3878 
3879 	/* combine the user config with event to determine if permanent
3880 	 * addresses are to be removed from address hash table
3881 	 */
3882 	if (!unregister && !idev->cnf.disable_ipv6) {
3883 		/* aggregate the system setting and interface setting */
3884 		int _keep_addr = READ_ONCE(net->ipv6.devconf_all->keep_addr_on_down);
3885 
3886 		if (!_keep_addr)
3887 			_keep_addr = READ_ONCE(idev->cnf.keep_addr_on_down);
3888 
3889 		keep_addr = (_keep_addr > 0);
3890 	}
3891 
3892 	/* Step 2: clear hash table */
3893 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
3894 		struct hlist_head *h = &net->ipv6.inet6_addr_lst[i];
3895 
3896 		spin_lock_bh(&net->ipv6.addrconf_hash_lock);
3897 restart:
3898 		hlist_for_each_entry_rcu(ifa, h, addr_lst) {
3899 			if (ifa->idev == idev) {
3900 				addrconf_del_dad_work(ifa);
3901 				/* combined flag + permanent flag decide if
3902 				 * address is retained on a down event
3903 				 */
3904 				if (!keep_addr ||
3905 				    !(ifa->flags & IFA_F_PERMANENT) ||
3906 				    addr_is_local(&ifa->addr)) {
3907 					hlist_del_init_rcu(&ifa->addr_lst);
3908 					goto restart;
3909 				}
3910 			}
3911 		}
3912 		spin_unlock_bh(&net->ipv6.addrconf_hash_lock);
3913 	}
3914 
3915 	write_lock_bh(&idev->lock);
3916 
3917 	addrconf_del_rs_timer(idev);
3918 
3919 	/* Step 2: clear flags for stateless addrconf, repeated down
3920 	 *         detection
3921 	 */
3922 	was_ready = idev->if_flags & IF_READY;
3923 	if (!unregister)
3924 		idev->if_flags &= ~(IF_RS_SENT|IF_RA_RCVD|IF_READY);
3925 
3926 	/* Step 3: clear tempaddr list */
3927 	while (!list_empty(&idev->tempaddr_list)) {
3928 		ifa = list_first_entry(&idev->tempaddr_list,
3929 				       struct inet6_ifaddr, tmp_list);
3930 		list_del(&ifa->tmp_list);
3931 		write_unlock_bh(&idev->lock);
3932 		spin_lock_bh(&ifa->lock);
3933 
3934 		if (ifa->ifpub) {
3935 			in6_ifa_put(ifa->ifpub);
3936 			ifa->ifpub = NULL;
3937 		}
3938 		spin_unlock_bh(&ifa->lock);
3939 		in6_ifa_put(ifa);
3940 		write_lock_bh(&idev->lock);
3941 	}
3942 
3943 	list_for_each_entry(ifa, &idev->addr_list, if_list)
3944 		list_add_tail(&ifa->if_list_aux, &tmp_addr_list);
3945 	write_unlock_bh(&idev->lock);
3946 
3947 	while (!list_empty(&tmp_addr_list)) {
3948 		struct fib6_info *rt = NULL;
3949 		bool keep;
3950 
3951 		ifa = list_first_entry(&tmp_addr_list,
3952 				       struct inet6_ifaddr, if_list_aux);
3953 		list_del(&ifa->if_list_aux);
3954 
3955 		addrconf_del_dad_work(ifa);
3956 
3957 		keep = keep_addr && (ifa->flags & IFA_F_PERMANENT) &&
3958 			!addr_is_local(&ifa->addr);
3959 
3960 		spin_lock_bh(&ifa->lock);
3961 
3962 		if (keep) {
3963 			/* set state to skip the notifier below */
3964 			state = INET6_IFADDR_STATE_DEAD;
3965 			ifa->state = INET6_IFADDR_STATE_PREDAD;
3966 			if (!(ifa->flags & IFA_F_NODAD))
3967 				ifa->flags |= IFA_F_TENTATIVE;
3968 
3969 			rt = ifa->rt;
3970 			ifa->rt = NULL;
3971 		} else {
3972 			state = ifa->state;
3973 			ifa->state = INET6_IFADDR_STATE_DEAD;
3974 		}
3975 
3976 		spin_unlock_bh(&ifa->lock);
3977 
3978 		if (rt)
3979 			ip6_del_rt(net, rt, false);
3980 
3981 		if (state != INET6_IFADDR_STATE_DEAD) {
3982 			__ipv6_ifa_notify(RTM_DELADDR, ifa);
3983 			inet6addr_notifier_call_chain(NETDEV_DOWN, ifa);
3984 		} else {
3985 			if (idev->cnf.forwarding)
3986 				addrconf_leave_anycast(ifa);
3987 			addrconf_leave_solict(ifa->idev, &ifa->addr);
3988 		}
3989 
3990 		if (!keep) {
3991 			write_lock_bh(&idev->lock);
3992 			list_del_rcu(&ifa->if_list);
3993 			write_unlock_bh(&idev->lock);
3994 			in6_ifa_put(ifa);
3995 		}
3996 	}
3997 
3998 	/* Step 5: Discard anycast and multicast list */
3999 	if (unregister) {
4000 		ipv6_ac_destroy_dev(idev);
4001 		ipv6_mc_destroy_dev(idev);
4002 	} else if (was_ready) {
4003 		ipv6_mc_down(idev);
4004 	}
4005 
4006 	WRITE_ONCE(idev->tstamp, jiffies);
4007 	idev->ra_mtu = 0;
4008 
4009 	/* Last: Shot the device (if unregistered) */
4010 	if (unregister) {
4011 		addrconf_sysctl_unregister(idev);
4012 		neigh_parms_release(&nd_tbl, idev->nd_parms);
4013 		neigh_ifdown(&nd_tbl, dev);
4014 		in6_dev_put(idev);
4015 	}
4016 	return 0;
4017 }
4018 
4019 static void addrconf_rs_timer(struct timer_list *t)
4020 {
4021 	struct inet6_dev *idev = from_timer(idev, t, rs_timer);
4022 	struct net_device *dev = idev->dev;
4023 	struct in6_addr lladdr;
4024 	int rtr_solicits;
4025 
4026 	write_lock(&idev->lock);
4027 	if (idev->dead || !(idev->if_flags & IF_READY))
4028 		goto out;
4029 
4030 	if (!ipv6_accept_ra(idev))
4031 		goto out;
4032 
4033 	/* Announcement received after solicitation was sent */
4034 	if (idev->if_flags & IF_RA_RCVD)
4035 		goto out;
4036 
4037 	rtr_solicits = READ_ONCE(idev->cnf.rtr_solicits);
4038 
4039 	if (idev->rs_probes++ < rtr_solicits || rtr_solicits < 0) {
4040 		write_unlock(&idev->lock);
4041 		if (!ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4042 			ndisc_send_rs(dev, &lladdr,
4043 				      &in6addr_linklocal_allrouters);
4044 		else
4045 			goto put;
4046 
4047 		write_lock(&idev->lock);
4048 		idev->rs_interval = rfc3315_s14_backoff_update(
4049 				idev->rs_interval,
4050 				READ_ONCE(idev->cnf.rtr_solicit_max_interval));
4051 		/* The wait after the last probe can be shorter */
4052 		addrconf_mod_rs_timer(idev, (idev->rs_probes ==
4053 					     READ_ONCE(idev->cnf.rtr_solicits)) ?
4054 				      READ_ONCE(idev->cnf.rtr_solicit_delay) :
4055 				      idev->rs_interval);
4056 	} else {
4057 		/*
4058 		 * Note: we do not support deprecated "all on-link"
4059 		 * assumption any longer.
4060 		 */
4061 		pr_debug("%s: no IPv6 routers present\n", idev->dev->name);
4062 	}
4063 
4064 out:
4065 	write_unlock(&idev->lock);
4066 put:
4067 	in6_dev_put(idev);
4068 }
4069 
4070 /*
4071  *	Duplicate Address Detection
4072  */
4073 static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
4074 {
4075 	struct inet6_dev *idev = ifp->idev;
4076 	unsigned long rand_num;
4077 	u64 nonce;
4078 
4079 	if (ifp->flags & IFA_F_OPTIMISTIC)
4080 		rand_num = 0;
4081 	else
4082 		rand_num = get_random_u32_below(
4083 				READ_ONCE(idev->cnf.rtr_solicit_delay) ? : 1);
4084 
4085 	nonce = 0;
4086 	if (READ_ONCE(idev->cnf.enhanced_dad) ||
4087 	    READ_ONCE(dev_net(idev->dev)->ipv6.devconf_all->enhanced_dad)) {
4088 		do
4089 			get_random_bytes(&nonce, 6);
4090 		while (nonce == 0);
4091 	}
4092 	ifp->dad_nonce = nonce;
4093 	ifp->dad_probes = READ_ONCE(idev->cnf.dad_transmits);
4094 	addrconf_mod_dad_work(ifp, rand_num);
4095 }
4096 
4097 static void addrconf_dad_begin(struct inet6_ifaddr *ifp)
4098 {
4099 	struct inet6_dev *idev = ifp->idev;
4100 	struct net_device *dev = idev->dev;
4101 	bool bump_id, notify = false;
4102 	struct net *net;
4103 
4104 	addrconf_join_solict(dev, &ifp->addr);
4105 
4106 	read_lock_bh(&idev->lock);
4107 	spin_lock(&ifp->lock);
4108 	if (ifp->state == INET6_IFADDR_STATE_DEAD)
4109 		goto out;
4110 
4111 	net = dev_net(dev);
4112 	if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
4113 	    (READ_ONCE(net->ipv6.devconf_all->accept_dad) < 1 &&
4114 	     READ_ONCE(idev->cnf.accept_dad) < 1) ||
4115 	    !(ifp->flags&IFA_F_TENTATIVE) ||
4116 	    ifp->flags & IFA_F_NODAD) {
4117 		bool send_na = false;
4118 
4119 		if (ifp->flags & IFA_F_TENTATIVE &&
4120 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4121 			send_na = true;
4122 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4123 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4124 		spin_unlock(&ifp->lock);
4125 		read_unlock_bh(&idev->lock);
4126 
4127 		addrconf_dad_completed(ifp, bump_id, send_na);
4128 		return;
4129 	}
4130 
4131 	if (!(idev->if_flags & IF_READY)) {
4132 		spin_unlock(&ifp->lock);
4133 		read_unlock_bh(&idev->lock);
4134 		/*
4135 		 * If the device is not ready:
4136 		 * - keep it tentative if it is a permanent address.
4137 		 * - otherwise, kill it.
4138 		 */
4139 		in6_ifa_hold(ifp);
4140 		addrconf_dad_stop(ifp, 0);
4141 		return;
4142 	}
4143 
4144 	/*
4145 	 * Optimistic nodes can start receiving
4146 	 * Frames right away
4147 	 */
4148 	if (ifp->flags & IFA_F_OPTIMISTIC) {
4149 		ip6_ins_rt(net, ifp->rt);
4150 		if (ipv6_use_optimistic_addr(net, idev)) {
4151 			/* Because optimistic nodes can use this address,
4152 			 * notify listeners. If DAD fails, RTM_DELADDR is sent.
4153 			 */
4154 			notify = true;
4155 		}
4156 	}
4157 
4158 	addrconf_dad_kick(ifp);
4159 out:
4160 	spin_unlock(&ifp->lock);
4161 	read_unlock_bh(&idev->lock);
4162 	if (notify)
4163 		ipv6_ifa_notify(RTM_NEWADDR, ifp);
4164 }
4165 
4166 static void addrconf_dad_start(struct inet6_ifaddr *ifp)
4167 {
4168 	bool begin_dad = false;
4169 
4170 	spin_lock_bh(&ifp->lock);
4171 	if (ifp->state != INET6_IFADDR_STATE_DEAD) {
4172 		ifp->state = INET6_IFADDR_STATE_PREDAD;
4173 		begin_dad = true;
4174 	}
4175 	spin_unlock_bh(&ifp->lock);
4176 
4177 	if (begin_dad)
4178 		addrconf_mod_dad_work(ifp, 0);
4179 }
4180 
4181 static void addrconf_dad_work(struct work_struct *w)
4182 {
4183 	struct inet6_ifaddr *ifp = container_of(to_delayed_work(w),
4184 						struct inet6_ifaddr,
4185 						dad_work);
4186 	struct inet6_dev *idev = ifp->idev;
4187 	bool bump_id, disable_ipv6 = false;
4188 	struct in6_addr mcaddr;
4189 
4190 	enum {
4191 		DAD_PROCESS,
4192 		DAD_BEGIN,
4193 		DAD_ABORT,
4194 	} action = DAD_PROCESS;
4195 
4196 	rtnl_lock();
4197 
4198 	spin_lock_bh(&ifp->lock);
4199 	if (ifp->state == INET6_IFADDR_STATE_PREDAD) {
4200 		action = DAD_BEGIN;
4201 		ifp->state = INET6_IFADDR_STATE_DAD;
4202 	} else if (ifp->state == INET6_IFADDR_STATE_ERRDAD) {
4203 		action = DAD_ABORT;
4204 		ifp->state = INET6_IFADDR_STATE_POSTDAD;
4205 
4206 		if ((READ_ONCE(dev_net(idev->dev)->ipv6.devconf_all->accept_dad) > 1 ||
4207 		     READ_ONCE(idev->cnf.accept_dad) > 1) &&
4208 		    !idev->cnf.disable_ipv6 &&
4209 		    !(ifp->flags & IFA_F_STABLE_PRIVACY)) {
4210 			struct in6_addr addr;
4211 
4212 			addr.s6_addr32[0] = htonl(0xfe800000);
4213 			addr.s6_addr32[1] = 0;
4214 
4215 			if (!ipv6_generate_eui64(addr.s6_addr + 8, idev->dev) &&
4216 			    ipv6_addr_equal(&ifp->addr, &addr)) {
4217 				/* DAD failed for link-local based on MAC */
4218 				WRITE_ONCE(idev->cnf.disable_ipv6, 1);
4219 
4220 				pr_info("%s: IPv6 being disabled!\n",
4221 					ifp->idev->dev->name);
4222 				disable_ipv6 = true;
4223 			}
4224 		}
4225 	}
4226 	spin_unlock_bh(&ifp->lock);
4227 
4228 	if (action == DAD_BEGIN) {
4229 		addrconf_dad_begin(ifp);
4230 		goto out;
4231 	} else if (action == DAD_ABORT) {
4232 		in6_ifa_hold(ifp);
4233 		addrconf_dad_stop(ifp, 1);
4234 		if (disable_ipv6)
4235 			addrconf_ifdown(idev->dev, false);
4236 		goto out;
4237 	}
4238 
4239 	if (!ifp->dad_probes && addrconf_dad_end(ifp))
4240 		goto out;
4241 
4242 	write_lock_bh(&idev->lock);
4243 	if (idev->dead || !(idev->if_flags & IF_READY)) {
4244 		write_unlock_bh(&idev->lock);
4245 		goto out;
4246 	}
4247 
4248 	spin_lock(&ifp->lock);
4249 	if (ifp->state == INET6_IFADDR_STATE_DEAD) {
4250 		spin_unlock(&ifp->lock);
4251 		write_unlock_bh(&idev->lock);
4252 		goto out;
4253 	}
4254 
4255 	if (ifp->dad_probes == 0) {
4256 		bool send_na = false;
4257 
4258 		/*
4259 		 * DAD was successful
4260 		 */
4261 
4262 		if (ifp->flags & IFA_F_TENTATIVE &&
4263 		    !(ifp->flags & IFA_F_OPTIMISTIC))
4264 			send_na = true;
4265 		bump_id = ifp->flags & IFA_F_TENTATIVE;
4266 		ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC|IFA_F_DADFAILED);
4267 		spin_unlock(&ifp->lock);
4268 		write_unlock_bh(&idev->lock);
4269 
4270 		addrconf_dad_completed(ifp, bump_id, send_na);
4271 
4272 		goto out;
4273 	}
4274 
4275 	ifp->dad_probes--;
4276 	addrconf_mod_dad_work(ifp,
4277 			      max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME),
4278 				  HZ/100));
4279 	spin_unlock(&ifp->lock);
4280 	write_unlock_bh(&idev->lock);
4281 
4282 	/* send a neighbour solicitation for our addr */
4283 	addrconf_addr_solict_mult(&ifp->addr, &mcaddr);
4284 	ndisc_send_ns(ifp->idev->dev, &ifp->addr, &mcaddr, &in6addr_any,
4285 		      ifp->dad_nonce);
4286 out:
4287 	in6_ifa_put(ifp);
4288 	rtnl_unlock();
4289 }
4290 
4291 /* ifp->idev must be at least read locked */
4292 static bool ipv6_lonely_lladdr(struct inet6_ifaddr *ifp)
4293 {
4294 	struct inet6_ifaddr *ifpiter;
4295 	struct inet6_dev *idev = ifp->idev;
4296 
4297 	list_for_each_entry_reverse(ifpiter, &idev->addr_list, if_list) {
4298 		if (ifpiter->scope > IFA_LINK)
4299 			break;
4300 		if (ifp != ifpiter && ifpiter->scope == IFA_LINK &&
4301 		    (ifpiter->flags & (IFA_F_PERMANENT|IFA_F_TENTATIVE|
4302 				       IFA_F_OPTIMISTIC|IFA_F_DADFAILED)) ==
4303 		    IFA_F_PERMANENT)
4304 			return false;
4305 	}
4306 	return true;
4307 }
4308 
4309 static void addrconf_dad_completed(struct inet6_ifaddr *ifp, bool bump_id,
4310 				   bool send_na)
4311 {
4312 	struct net_device *dev = ifp->idev->dev;
4313 	struct in6_addr lladdr;
4314 	bool send_rs, send_mld;
4315 
4316 	addrconf_del_dad_work(ifp);
4317 
4318 	/*
4319 	 *	Configure the address for reception. Now it is valid.
4320 	 */
4321 
4322 	ipv6_ifa_notify(RTM_NEWADDR, ifp);
4323 
4324 	/* If added prefix is link local and we are prepared to process
4325 	   router advertisements, start sending router solicitations.
4326 	 */
4327 
4328 	read_lock_bh(&ifp->idev->lock);
4329 	send_mld = ifp->scope == IFA_LINK && ipv6_lonely_lladdr(ifp);
4330 	send_rs = send_mld &&
4331 		  ipv6_accept_ra(ifp->idev) &&
4332 		  READ_ONCE(ifp->idev->cnf.rtr_solicits) != 0 &&
4333 		  (dev->flags & IFF_LOOPBACK) == 0 &&
4334 		  (dev->type != ARPHRD_TUNNEL) &&
4335 		  !netif_is_team_port(dev);
4336 	read_unlock_bh(&ifp->idev->lock);
4337 
4338 	/* While dad is in progress mld report's source address is in6_addrany.
4339 	 * Resend with proper ll now.
4340 	 */
4341 	if (send_mld)
4342 		ipv6_mc_dad_complete(ifp->idev);
4343 
4344 	/* send unsolicited NA if enabled */
4345 	if (send_na &&
4346 	    (READ_ONCE(ifp->idev->cnf.ndisc_notify) ||
4347 	     READ_ONCE(dev_net(dev)->ipv6.devconf_all->ndisc_notify))) {
4348 		ndisc_send_na(dev, &in6addr_linklocal_allnodes, &ifp->addr,
4349 			      /*router=*/ !!ifp->idev->cnf.forwarding,
4350 			      /*solicited=*/ false, /*override=*/ true,
4351 			      /*inc_opt=*/ true);
4352 	}
4353 
4354 	if (send_rs) {
4355 		/*
4356 		 *	If a host as already performed a random delay
4357 		 *	[...] as part of DAD [...] there is no need
4358 		 *	to delay again before sending the first RS
4359 		 */
4360 		if (ipv6_get_lladdr(dev, &lladdr, IFA_F_TENTATIVE))
4361 			return;
4362 		ndisc_send_rs(dev, &lladdr, &in6addr_linklocal_allrouters);
4363 
4364 		write_lock_bh(&ifp->idev->lock);
4365 		spin_lock(&ifp->lock);
4366 		ifp->idev->rs_interval = rfc3315_s14_backoff_init(
4367 			READ_ONCE(ifp->idev->cnf.rtr_solicit_interval));
4368 		ifp->idev->rs_probes = 1;
4369 		ifp->idev->if_flags |= IF_RS_SENT;
4370 		addrconf_mod_rs_timer(ifp->idev, ifp->idev->rs_interval);
4371 		spin_unlock(&ifp->lock);
4372 		write_unlock_bh(&ifp->idev->lock);
4373 	}
4374 
4375 	if (bump_id)
4376 		rt_genid_bump_ipv6(dev_net(dev));
4377 
4378 	/* Make sure that a new temporary address will be created
4379 	 * before this temporary address becomes deprecated.
4380 	 */
4381 	if (ifp->flags & IFA_F_TEMPORARY)
4382 		addrconf_verify_rtnl(dev_net(dev));
4383 }
4384 
4385 static void addrconf_dad_run(struct inet6_dev *idev, bool restart)
4386 {
4387 	struct inet6_ifaddr *ifp;
4388 
4389 	read_lock_bh(&idev->lock);
4390 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
4391 		spin_lock(&ifp->lock);
4392 		if ((ifp->flags & IFA_F_TENTATIVE &&
4393 		     ifp->state == INET6_IFADDR_STATE_DAD) || restart) {
4394 			if (restart)
4395 				ifp->state = INET6_IFADDR_STATE_PREDAD;
4396 			addrconf_dad_kick(ifp);
4397 		}
4398 		spin_unlock(&ifp->lock);
4399 	}
4400 	read_unlock_bh(&idev->lock);
4401 }
4402 
4403 #ifdef CONFIG_PROC_FS
4404 struct if6_iter_state {
4405 	struct seq_net_private p;
4406 	int bucket;
4407 	int offset;
4408 };
4409 
4410 static struct inet6_ifaddr *if6_get_first(struct seq_file *seq, loff_t pos)
4411 {
4412 	struct if6_iter_state *state = seq->private;
4413 	struct net *net = seq_file_net(seq);
4414 	struct inet6_ifaddr *ifa = NULL;
4415 	int p = 0;
4416 
4417 	/* initial bucket if pos is 0 */
4418 	if (pos == 0) {
4419 		state->bucket = 0;
4420 		state->offset = 0;
4421 	}
4422 
4423 	for (; state->bucket < IN6_ADDR_HSIZE; ++state->bucket) {
4424 		hlist_for_each_entry_rcu(ifa, &net->ipv6.inet6_addr_lst[state->bucket],
4425 					 addr_lst) {
4426 			/* sync with offset */
4427 			if (p < state->offset) {
4428 				p++;
4429 				continue;
4430 			}
4431 			return ifa;
4432 		}
4433 
4434 		/* prepare for next bucket */
4435 		state->offset = 0;
4436 		p = 0;
4437 	}
4438 	return NULL;
4439 }
4440 
4441 static struct inet6_ifaddr *if6_get_next(struct seq_file *seq,
4442 					 struct inet6_ifaddr *ifa)
4443 {
4444 	struct if6_iter_state *state = seq->private;
4445 	struct net *net = seq_file_net(seq);
4446 
4447 	hlist_for_each_entry_continue_rcu(ifa, addr_lst) {
4448 		state->offset++;
4449 		return ifa;
4450 	}
4451 
4452 	state->offset = 0;
4453 	while (++state->bucket < IN6_ADDR_HSIZE) {
4454 		hlist_for_each_entry_rcu(ifa,
4455 				     &net->ipv6.inet6_addr_lst[state->bucket], addr_lst) {
4456 			return ifa;
4457 		}
4458 	}
4459 
4460 	return NULL;
4461 }
4462 
4463 static void *if6_seq_start(struct seq_file *seq, loff_t *pos)
4464 	__acquires(rcu)
4465 {
4466 	rcu_read_lock();
4467 	return if6_get_first(seq, *pos);
4468 }
4469 
4470 static void *if6_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4471 {
4472 	struct inet6_ifaddr *ifa;
4473 
4474 	ifa = if6_get_next(seq, v);
4475 	++*pos;
4476 	return ifa;
4477 }
4478 
4479 static void if6_seq_stop(struct seq_file *seq, void *v)
4480 	__releases(rcu)
4481 {
4482 	rcu_read_unlock();
4483 }
4484 
4485 static int if6_seq_show(struct seq_file *seq, void *v)
4486 {
4487 	struct inet6_ifaddr *ifp = (struct inet6_ifaddr *)v;
4488 	seq_printf(seq, "%pi6 %02x %02x %02x %02x %8s\n",
4489 		   &ifp->addr,
4490 		   ifp->idev->dev->ifindex,
4491 		   ifp->prefix_len,
4492 		   ifp->scope,
4493 		   (u8) ifp->flags,
4494 		   ifp->idev->dev->name);
4495 	return 0;
4496 }
4497 
4498 static const struct seq_operations if6_seq_ops = {
4499 	.start	= if6_seq_start,
4500 	.next	= if6_seq_next,
4501 	.show	= if6_seq_show,
4502 	.stop	= if6_seq_stop,
4503 };
4504 
4505 static int __net_init if6_proc_net_init(struct net *net)
4506 {
4507 	if (!proc_create_net("if_inet6", 0444, net->proc_net, &if6_seq_ops,
4508 			sizeof(struct if6_iter_state)))
4509 		return -ENOMEM;
4510 	return 0;
4511 }
4512 
4513 static void __net_exit if6_proc_net_exit(struct net *net)
4514 {
4515 	remove_proc_entry("if_inet6", net->proc_net);
4516 }
4517 
4518 static struct pernet_operations if6_proc_net_ops = {
4519 	.init = if6_proc_net_init,
4520 	.exit = if6_proc_net_exit,
4521 };
4522 
4523 int __init if6_proc_init(void)
4524 {
4525 	return register_pernet_subsys(&if6_proc_net_ops);
4526 }
4527 
4528 void if6_proc_exit(void)
4529 {
4530 	unregister_pernet_subsys(&if6_proc_net_ops);
4531 }
4532 #endif	/* CONFIG_PROC_FS */
4533 
4534 #if IS_ENABLED(CONFIG_IPV6_MIP6)
4535 /* Check if address is a home address configured on any interface. */
4536 int ipv6_chk_home_addr(struct net *net, const struct in6_addr *addr)
4537 {
4538 	unsigned int hash = inet6_addr_hash(net, addr);
4539 	struct inet6_ifaddr *ifp = NULL;
4540 	int ret = 0;
4541 
4542 	rcu_read_lock();
4543 	hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
4544 		if (ipv6_addr_equal(&ifp->addr, addr) &&
4545 		    (ifp->flags & IFA_F_HOMEADDRESS)) {
4546 			ret = 1;
4547 			break;
4548 		}
4549 	}
4550 	rcu_read_unlock();
4551 	return ret;
4552 }
4553 #endif
4554 
4555 /* RFC6554 has some algorithm to avoid loops in segment routing by
4556  * checking if the segments contains any of a local interface address.
4557  *
4558  * Quote:
4559  *
4560  * To detect loops in the SRH, a router MUST determine if the SRH
4561  * includes multiple addresses assigned to any interface on that router.
4562  * If such addresses appear more than once and are separated by at least
4563  * one address not assigned to that router.
4564  */
4565 int ipv6_chk_rpl_srh_loop(struct net *net, const struct in6_addr *segs,
4566 			  unsigned char nsegs)
4567 {
4568 	const struct in6_addr *addr;
4569 	int i, ret = 0, found = 0;
4570 	struct inet6_ifaddr *ifp;
4571 	bool separated = false;
4572 	unsigned int hash;
4573 	bool hash_found;
4574 
4575 	rcu_read_lock();
4576 	for (i = 0; i < nsegs; i++) {
4577 		addr = &segs[i];
4578 		hash = inet6_addr_hash(net, addr);
4579 
4580 		hash_found = false;
4581 		hlist_for_each_entry_rcu(ifp, &net->ipv6.inet6_addr_lst[hash], addr_lst) {
4582 
4583 			if (ipv6_addr_equal(&ifp->addr, addr)) {
4584 				hash_found = true;
4585 				break;
4586 			}
4587 		}
4588 
4589 		if (hash_found) {
4590 			if (found > 1 && separated) {
4591 				ret = 1;
4592 				break;
4593 			}
4594 
4595 			separated = false;
4596 			found++;
4597 		} else {
4598 			separated = true;
4599 		}
4600 	}
4601 	rcu_read_unlock();
4602 
4603 	return ret;
4604 }
4605 
4606 /*
4607  *	Periodic address status verification
4608  */
4609 
4610 static void addrconf_verify_rtnl(struct net *net)
4611 {
4612 	unsigned long now, next, next_sec, next_sched;
4613 	struct inet6_ifaddr *ifp;
4614 	int i;
4615 
4616 	ASSERT_RTNL();
4617 
4618 	rcu_read_lock_bh();
4619 	now = jiffies;
4620 	next = round_jiffies_up(now + ADDR_CHECK_FREQUENCY);
4621 
4622 	cancel_delayed_work(&net->ipv6.addr_chk_work);
4623 
4624 	for (i = 0; i < IN6_ADDR_HSIZE; i++) {
4625 restart:
4626 		hlist_for_each_entry_rcu_bh(ifp, &net->ipv6.inet6_addr_lst[i], addr_lst) {
4627 			unsigned long age;
4628 
4629 			/* When setting preferred_lft to a value not zero or
4630 			 * infinity, while valid_lft is infinity
4631 			 * IFA_F_PERMANENT has a non-infinity life time.
4632 			 */
4633 			if ((ifp->flags & IFA_F_PERMANENT) &&
4634 			    (ifp->prefered_lft == INFINITY_LIFE_TIME))
4635 				continue;
4636 
4637 			spin_lock(&ifp->lock);
4638 			/* We try to batch several events at once. */
4639 			age = (now - ifp->tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ;
4640 
4641 			if ((ifp->flags&IFA_F_TEMPORARY) &&
4642 			    !(ifp->flags&IFA_F_TENTATIVE) &&
4643 			    ifp->prefered_lft != INFINITY_LIFE_TIME &&
4644 			    !ifp->regen_count && ifp->ifpub) {
4645 				/* This is a non-regenerated temporary addr. */
4646 
4647 				unsigned long regen_advance = ipv6_get_regen_advance(ifp->idev);
4648 
4649 				if (age + regen_advance >= ifp->prefered_lft) {
4650 					struct inet6_ifaddr *ifpub = ifp->ifpub;
4651 					if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4652 						next = ifp->tstamp + ifp->prefered_lft * HZ;
4653 
4654 					ifp->regen_count++;
4655 					in6_ifa_hold(ifp);
4656 					in6_ifa_hold(ifpub);
4657 					spin_unlock(&ifp->lock);
4658 
4659 					spin_lock(&ifpub->lock);
4660 					ifpub->regen_count = 0;
4661 					spin_unlock(&ifpub->lock);
4662 					rcu_read_unlock_bh();
4663 					ipv6_create_tempaddr(ifpub, true);
4664 					in6_ifa_put(ifpub);
4665 					in6_ifa_put(ifp);
4666 					rcu_read_lock_bh();
4667 					goto restart;
4668 				} else if (time_before(ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ, next))
4669 					next = ifp->tstamp + ifp->prefered_lft * HZ - regen_advance * HZ;
4670 			}
4671 
4672 			if (ifp->valid_lft != INFINITY_LIFE_TIME &&
4673 			    age >= ifp->valid_lft) {
4674 				spin_unlock(&ifp->lock);
4675 				in6_ifa_hold(ifp);
4676 				rcu_read_unlock_bh();
4677 				ipv6_del_addr(ifp);
4678 				rcu_read_lock_bh();
4679 				goto restart;
4680 			} else if (ifp->prefered_lft == INFINITY_LIFE_TIME) {
4681 				spin_unlock(&ifp->lock);
4682 				continue;
4683 			} else if (age >= ifp->prefered_lft) {
4684 				/* jiffies - ifp->tstamp > age >= ifp->prefered_lft */
4685 				int deprecate = 0;
4686 
4687 				if (!(ifp->flags&IFA_F_DEPRECATED)) {
4688 					deprecate = 1;
4689 					ifp->flags |= IFA_F_DEPRECATED;
4690 				}
4691 
4692 				if ((ifp->valid_lft != INFINITY_LIFE_TIME) &&
4693 				    (time_before(ifp->tstamp + ifp->valid_lft * HZ, next)))
4694 					next = ifp->tstamp + ifp->valid_lft * HZ;
4695 
4696 				spin_unlock(&ifp->lock);
4697 
4698 				if (deprecate) {
4699 					in6_ifa_hold(ifp);
4700 
4701 					ipv6_ifa_notify(0, ifp);
4702 					in6_ifa_put(ifp);
4703 					goto restart;
4704 				}
4705 			} else {
4706 				/* ifp->prefered_lft <= ifp->valid_lft */
4707 				if (time_before(ifp->tstamp + ifp->prefered_lft * HZ, next))
4708 					next = ifp->tstamp + ifp->prefered_lft * HZ;
4709 				spin_unlock(&ifp->lock);
4710 			}
4711 		}
4712 	}
4713 
4714 	next_sec = round_jiffies_up(next);
4715 	next_sched = next;
4716 
4717 	/* If rounded timeout is accurate enough, accept it. */
4718 	if (time_before(next_sec, next + ADDRCONF_TIMER_FUZZ))
4719 		next_sched = next_sec;
4720 
4721 	/* And minimum interval is ADDRCONF_TIMER_FUZZ_MAX. */
4722 	if (time_before(next_sched, jiffies + ADDRCONF_TIMER_FUZZ_MAX))
4723 		next_sched = jiffies + ADDRCONF_TIMER_FUZZ_MAX;
4724 
4725 	pr_debug("now = %lu, schedule = %lu, rounded schedule = %lu => %lu\n",
4726 		 now, next, next_sec, next_sched);
4727 	mod_delayed_work(addrconf_wq, &net->ipv6.addr_chk_work, next_sched - now);
4728 	rcu_read_unlock_bh();
4729 }
4730 
4731 static void addrconf_verify_work(struct work_struct *w)
4732 {
4733 	struct net *net = container_of(to_delayed_work(w), struct net,
4734 				       ipv6.addr_chk_work);
4735 
4736 	rtnl_lock();
4737 	addrconf_verify_rtnl(net);
4738 	rtnl_unlock();
4739 }
4740 
4741 static void addrconf_verify(struct net *net)
4742 {
4743 	mod_delayed_work(addrconf_wq, &net->ipv6.addr_chk_work, 0);
4744 }
4745 
4746 static struct in6_addr *extract_addr(struct nlattr *addr, struct nlattr *local,
4747 				     struct in6_addr **peer_pfx)
4748 {
4749 	struct in6_addr *pfx = NULL;
4750 
4751 	*peer_pfx = NULL;
4752 
4753 	if (addr)
4754 		pfx = nla_data(addr);
4755 
4756 	if (local) {
4757 		if (pfx && nla_memcmp(local, pfx, sizeof(*pfx)))
4758 			*peer_pfx = pfx;
4759 		pfx = nla_data(local);
4760 	}
4761 
4762 	return pfx;
4763 }
4764 
4765 static const struct nla_policy ifa_ipv6_policy[IFA_MAX+1] = {
4766 	[IFA_ADDRESS]		= { .len = sizeof(struct in6_addr) },
4767 	[IFA_LOCAL]		= { .len = sizeof(struct in6_addr) },
4768 	[IFA_CACHEINFO]		= { .len = sizeof(struct ifa_cacheinfo) },
4769 	[IFA_FLAGS]		= { .len = sizeof(u32) },
4770 	[IFA_RT_PRIORITY]	= { .len = sizeof(u32) },
4771 	[IFA_TARGET_NETNSID]	= { .type = NLA_S32 },
4772 	[IFA_PROTO]		= { .type = NLA_U8 },
4773 };
4774 
4775 static int
4776 inet6_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
4777 		  struct netlink_ext_ack *extack)
4778 {
4779 	struct net *net = sock_net(skb->sk);
4780 	struct ifaddrmsg *ifm;
4781 	struct nlattr *tb[IFA_MAX+1];
4782 	struct in6_addr *pfx, *peer_pfx;
4783 	u32 ifa_flags;
4784 	int err;
4785 
4786 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4787 				     ifa_ipv6_policy, extack);
4788 	if (err < 0)
4789 		return err;
4790 
4791 	ifm = nlmsg_data(nlh);
4792 	pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4793 	if (!pfx)
4794 		return -EINVAL;
4795 
4796 	ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
4797 
4798 	/* We ignore other flags so far. */
4799 	ifa_flags &= IFA_F_MANAGETEMPADDR;
4800 
4801 	return inet6_addr_del(net, ifm->ifa_index, ifa_flags, pfx,
4802 			      ifm->ifa_prefixlen, extack);
4803 }
4804 
4805 static int modify_prefix_route(struct inet6_ifaddr *ifp,
4806 			       unsigned long expires, u32 flags,
4807 			       bool modify_peer)
4808 {
4809 	struct fib6_table *table;
4810 	struct fib6_info *f6i;
4811 	u32 prio;
4812 
4813 	f6i = addrconf_get_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4814 					ifp->prefix_len,
4815 					ifp->idev->dev, 0, RTF_DEFAULT, true);
4816 	if (!f6i)
4817 		return -ENOENT;
4818 
4819 	prio = ifp->rt_priority ? : IP6_RT_PRIO_ADDRCONF;
4820 	if (f6i->fib6_metric != prio) {
4821 		/* delete old one */
4822 		ip6_del_rt(dev_net(ifp->idev->dev), f6i, false);
4823 
4824 		/* add new one */
4825 		addrconf_prefix_route(modify_peer ? &ifp->peer_addr : &ifp->addr,
4826 				      ifp->prefix_len,
4827 				      ifp->rt_priority, ifp->idev->dev,
4828 				      expires, flags, GFP_KERNEL);
4829 	} else {
4830 		table = f6i->fib6_table;
4831 		spin_lock_bh(&table->tb6_lock);
4832 
4833 		if (!(flags & RTF_EXPIRES)) {
4834 			fib6_clean_expires(f6i);
4835 			fib6_remove_gc_list(f6i);
4836 		} else {
4837 			fib6_set_expires(f6i, expires);
4838 			fib6_add_gc_list(f6i);
4839 		}
4840 
4841 		spin_unlock_bh(&table->tb6_lock);
4842 
4843 		fib6_info_release(f6i);
4844 	}
4845 
4846 	return 0;
4847 }
4848 
4849 static int inet6_addr_modify(struct net *net, struct inet6_ifaddr *ifp,
4850 			     struct ifa6_config *cfg)
4851 {
4852 	u32 flags;
4853 	clock_t expires;
4854 	unsigned long timeout;
4855 	bool was_managetempaddr;
4856 	bool had_prefixroute;
4857 	bool new_peer = false;
4858 
4859 	ASSERT_RTNL();
4860 
4861 	if (!cfg->valid_lft || cfg->preferred_lft > cfg->valid_lft)
4862 		return -EINVAL;
4863 
4864 	if (cfg->ifa_flags & IFA_F_MANAGETEMPADDR &&
4865 	    (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
4866 		return -EINVAL;
4867 
4868 	if (!(ifp->flags & IFA_F_TENTATIVE) || ifp->flags & IFA_F_DADFAILED)
4869 		cfg->ifa_flags &= ~IFA_F_OPTIMISTIC;
4870 
4871 	timeout = addrconf_timeout_fixup(cfg->valid_lft, HZ);
4872 	if (addrconf_finite_timeout(timeout)) {
4873 		expires = jiffies_to_clock_t(timeout * HZ);
4874 		cfg->valid_lft = timeout;
4875 		flags = RTF_EXPIRES;
4876 	} else {
4877 		expires = 0;
4878 		flags = 0;
4879 		cfg->ifa_flags |= IFA_F_PERMANENT;
4880 	}
4881 
4882 	timeout = addrconf_timeout_fixup(cfg->preferred_lft, HZ);
4883 	if (addrconf_finite_timeout(timeout)) {
4884 		if (timeout == 0)
4885 			cfg->ifa_flags |= IFA_F_DEPRECATED;
4886 		cfg->preferred_lft = timeout;
4887 	}
4888 
4889 	if (cfg->peer_pfx &&
4890 	    memcmp(&ifp->peer_addr, cfg->peer_pfx, sizeof(struct in6_addr))) {
4891 		if (!ipv6_addr_any(&ifp->peer_addr))
4892 			cleanup_prefix_route(ifp, expires, true, true);
4893 		new_peer = true;
4894 	}
4895 
4896 	spin_lock_bh(&ifp->lock);
4897 	was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
4898 	had_prefixroute = ifp->flags & IFA_F_PERMANENT &&
4899 			  !(ifp->flags & IFA_F_NOPREFIXROUTE);
4900 	ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
4901 			IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR |
4902 			IFA_F_NOPREFIXROUTE);
4903 	ifp->flags |= cfg->ifa_flags;
4904 	WRITE_ONCE(ifp->tstamp, jiffies);
4905 	WRITE_ONCE(ifp->valid_lft, cfg->valid_lft);
4906 	WRITE_ONCE(ifp->prefered_lft, cfg->preferred_lft);
4907 	WRITE_ONCE(ifp->ifa_proto, cfg->ifa_proto);
4908 
4909 	if (cfg->rt_priority && cfg->rt_priority != ifp->rt_priority)
4910 		WRITE_ONCE(ifp->rt_priority, cfg->rt_priority);
4911 
4912 	if (new_peer)
4913 		ifp->peer_addr = *cfg->peer_pfx;
4914 
4915 	spin_unlock_bh(&ifp->lock);
4916 	if (!(ifp->flags&IFA_F_TENTATIVE))
4917 		ipv6_ifa_notify(0, ifp);
4918 
4919 	if (!(cfg->ifa_flags & IFA_F_NOPREFIXROUTE)) {
4920 		int rc = -ENOENT;
4921 
4922 		if (had_prefixroute)
4923 			rc = modify_prefix_route(ifp, expires, flags, false);
4924 
4925 		/* prefix route could have been deleted; if so restore it */
4926 		if (rc == -ENOENT) {
4927 			addrconf_prefix_route(&ifp->addr, ifp->prefix_len,
4928 					      ifp->rt_priority, ifp->idev->dev,
4929 					      expires, flags, GFP_KERNEL);
4930 		}
4931 
4932 		if (had_prefixroute && !ipv6_addr_any(&ifp->peer_addr))
4933 			rc = modify_prefix_route(ifp, expires, flags, true);
4934 
4935 		if (rc == -ENOENT && !ipv6_addr_any(&ifp->peer_addr)) {
4936 			addrconf_prefix_route(&ifp->peer_addr, ifp->prefix_len,
4937 					      ifp->rt_priority, ifp->idev->dev,
4938 					      expires, flags, GFP_KERNEL);
4939 		}
4940 	} else if (had_prefixroute) {
4941 		enum cleanup_prefix_rt_t action;
4942 		unsigned long rt_expires;
4943 
4944 		write_lock_bh(&ifp->idev->lock);
4945 		action = check_cleanup_prefix_route(ifp, &rt_expires);
4946 		write_unlock_bh(&ifp->idev->lock);
4947 
4948 		if (action != CLEANUP_PREFIX_RT_NOP) {
4949 			cleanup_prefix_route(ifp, rt_expires,
4950 				action == CLEANUP_PREFIX_RT_DEL, false);
4951 		}
4952 	}
4953 
4954 	if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
4955 		if (was_managetempaddr &&
4956 		    !(ifp->flags & IFA_F_MANAGETEMPADDR)) {
4957 			cfg->valid_lft = 0;
4958 			cfg->preferred_lft = 0;
4959 		}
4960 		manage_tempaddrs(ifp->idev, ifp, cfg->valid_lft,
4961 				 cfg->preferred_lft, !was_managetempaddr,
4962 				 jiffies);
4963 	}
4964 
4965 	addrconf_verify_rtnl(net);
4966 
4967 	return 0;
4968 }
4969 
4970 static int
4971 inet6_rtm_newaddr(struct sk_buff *skb, struct nlmsghdr *nlh,
4972 		  struct netlink_ext_ack *extack)
4973 {
4974 	struct net *net = sock_net(skb->sk);
4975 	struct ifaddrmsg *ifm;
4976 	struct nlattr *tb[IFA_MAX+1];
4977 	struct in6_addr *peer_pfx;
4978 	struct inet6_ifaddr *ifa;
4979 	struct net_device *dev;
4980 	struct inet6_dev *idev;
4981 	struct ifa6_config cfg;
4982 	int err;
4983 
4984 	err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
4985 				     ifa_ipv6_policy, extack);
4986 	if (err < 0)
4987 		return err;
4988 
4989 	memset(&cfg, 0, sizeof(cfg));
4990 
4991 	ifm = nlmsg_data(nlh);
4992 	cfg.pfx = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer_pfx);
4993 	if (!cfg.pfx)
4994 		return -EINVAL;
4995 
4996 	cfg.peer_pfx = peer_pfx;
4997 	cfg.plen = ifm->ifa_prefixlen;
4998 	if (tb[IFA_RT_PRIORITY])
4999 		cfg.rt_priority = nla_get_u32(tb[IFA_RT_PRIORITY]);
5000 
5001 	if (tb[IFA_PROTO])
5002 		cfg.ifa_proto = nla_get_u8(tb[IFA_PROTO]);
5003 
5004 	cfg.valid_lft = INFINITY_LIFE_TIME;
5005 	cfg.preferred_lft = INFINITY_LIFE_TIME;
5006 
5007 	if (tb[IFA_CACHEINFO]) {
5008 		struct ifa_cacheinfo *ci;
5009 
5010 		ci = nla_data(tb[IFA_CACHEINFO]);
5011 		cfg.valid_lft = ci->ifa_valid;
5012 		cfg.preferred_lft = ci->ifa_prefered;
5013 	}
5014 
5015 	dev =  __dev_get_by_index(net, ifm->ifa_index);
5016 	if (!dev) {
5017 		NL_SET_ERR_MSG_MOD(extack, "Unable to find the interface");
5018 		return -ENODEV;
5019 	}
5020 
5021 	if (tb[IFA_FLAGS])
5022 		cfg.ifa_flags = nla_get_u32(tb[IFA_FLAGS]);
5023 	else
5024 		cfg.ifa_flags = ifm->ifa_flags;
5025 
5026 	/* We ignore other flags so far. */
5027 	cfg.ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS |
5028 			 IFA_F_MANAGETEMPADDR | IFA_F_NOPREFIXROUTE |
5029 			 IFA_F_MCAUTOJOIN | IFA_F_OPTIMISTIC;
5030 
5031 	idev = ipv6_find_idev(dev);
5032 	if (IS_ERR(idev))
5033 		return PTR_ERR(idev);
5034 
5035 	if (!ipv6_allow_optimistic_dad(net, idev))
5036 		cfg.ifa_flags &= ~IFA_F_OPTIMISTIC;
5037 
5038 	if (cfg.ifa_flags & IFA_F_NODAD &&
5039 	    cfg.ifa_flags & IFA_F_OPTIMISTIC) {
5040 		NL_SET_ERR_MSG(extack, "IFA_F_NODAD and IFA_F_OPTIMISTIC are mutually exclusive");
5041 		return -EINVAL;
5042 	}
5043 
5044 	ifa = ipv6_get_ifaddr(net, cfg.pfx, dev, 1);
5045 	if (!ifa) {
5046 		/*
5047 		 * It would be best to check for !NLM_F_CREATE here but
5048 		 * userspace already relies on not having to provide this.
5049 		 */
5050 		return inet6_addr_add(net, ifm->ifa_index, &cfg, extack);
5051 	}
5052 
5053 	if (nlh->nlmsg_flags & NLM_F_EXCL ||
5054 	    !(nlh->nlmsg_flags & NLM_F_REPLACE)) {
5055 		NL_SET_ERR_MSG_MOD(extack, "address already assigned");
5056 		err = -EEXIST;
5057 	} else {
5058 		err = inet6_addr_modify(net, ifa, &cfg);
5059 	}
5060 
5061 	in6_ifa_put(ifa);
5062 
5063 	return err;
5064 }
5065 
5066 static void put_ifaddrmsg(struct nlmsghdr *nlh, u8 prefixlen, u32 flags,
5067 			  u8 scope, int ifindex)
5068 {
5069 	struct ifaddrmsg *ifm;
5070 
5071 	ifm = nlmsg_data(nlh);
5072 	ifm->ifa_family = AF_INET6;
5073 	ifm->ifa_prefixlen = prefixlen;
5074 	ifm->ifa_flags = flags;
5075 	ifm->ifa_scope = scope;
5076 	ifm->ifa_index = ifindex;
5077 }
5078 
5079 static int put_cacheinfo(struct sk_buff *skb, unsigned long cstamp,
5080 			 unsigned long tstamp, u32 preferred, u32 valid)
5081 {
5082 	struct ifa_cacheinfo ci;
5083 
5084 	ci.cstamp = cstamp_delta(cstamp);
5085 	ci.tstamp = cstamp_delta(tstamp);
5086 	ci.ifa_prefered = preferred;
5087 	ci.ifa_valid = valid;
5088 
5089 	return nla_put(skb, IFA_CACHEINFO, sizeof(ci), &ci);
5090 }
5091 
5092 static inline int rt_scope(int ifa_scope)
5093 {
5094 	if (ifa_scope & IFA_HOST)
5095 		return RT_SCOPE_HOST;
5096 	else if (ifa_scope & IFA_LINK)
5097 		return RT_SCOPE_LINK;
5098 	else if (ifa_scope & IFA_SITE)
5099 		return RT_SCOPE_SITE;
5100 	else
5101 		return RT_SCOPE_UNIVERSE;
5102 }
5103 
5104 static inline int inet6_ifaddr_msgsize(void)
5105 {
5106 	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
5107 	       + nla_total_size(16) /* IFA_LOCAL */
5108 	       + nla_total_size(16) /* IFA_ADDRESS */
5109 	       + nla_total_size(sizeof(struct ifa_cacheinfo))
5110 	       + nla_total_size(4)  /* IFA_FLAGS */
5111 	       + nla_total_size(1)  /* IFA_PROTO */
5112 	       + nla_total_size(4)  /* IFA_RT_PRIORITY */;
5113 }
5114 
5115 enum addr_type_t {
5116 	UNICAST_ADDR,
5117 	MULTICAST_ADDR,
5118 	ANYCAST_ADDR,
5119 };
5120 
5121 struct inet6_fill_args {
5122 	u32 portid;
5123 	u32 seq;
5124 	int event;
5125 	unsigned int flags;
5126 	int netnsid;
5127 	int ifindex;
5128 	enum addr_type_t type;
5129 };
5130 
5131 static int inet6_fill_ifaddr(struct sk_buff *skb,
5132 			     const struct inet6_ifaddr *ifa,
5133 			     struct inet6_fill_args *args)
5134 {
5135 	struct nlmsghdr *nlh;
5136 	u32 preferred, valid;
5137 	u32 flags, priority;
5138 	u8 proto;
5139 
5140 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5141 			sizeof(struct ifaddrmsg), args->flags);
5142 	if (!nlh)
5143 		return -EMSGSIZE;
5144 
5145 	flags = READ_ONCE(ifa->flags);
5146 	put_ifaddrmsg(nlh, ifa->prefix_len, ifa->flags, rt_scope(ifa->scope),
5147 		      ifa->idev->dev->ifindex);
5148 
5149 	if (args->netnsid >= 0 &&
5150 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid))
5151 		goto error;
5152 
5153 	preferred = READ_ONCE(ifa->prefered_lft);
5154 	valid = READ_ONCE(ifa->valid_lft);
5155 
5156 	if (!((flags & IFA_F_PERMANENT) &&
5157 	      (preferred == INFINITY_LIFE_TIME))) {
5158 		if (preferred != INFINITY_LIFE_TIME) {
5159 			long tval = (jiffies - READ_ONCE(ifa->tstamp)) / HZ;
5160 
5161 			if (preferred > tval)
5162 				preferred -= tval;
5163 			else
5164 				preferred = 0;
5165 			if (valid != INFINITY_LIFE_TIME) {
5166 				if (valid > tval)
5167 					valid -= tval;
5168 				else
5169 					valid = 0;
5170 			}
5171 		}
5172 	} else {
5173 		preferred = INFINITY_LIFE_TIME;
5174 		valid = INFINITY_LIFE_TIME;
5175 	}
5176 
5177 	if (!ipv6_addr_any(&ifa->peer_addr)) {
5178 		if (nla_put_in6_addr(skb, IFA_LOCAL, &ifa->addr) < 0 ||
5179 		    nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->peer_addr) < 0)
5180 			goto error;
5181 	} else {
5182 		if (nla_put_in6_addr(skb, IFA_ADDRESS, &ifa->addr) < 0)
5183 			goto error;
5184 	}
5185 
5186 	priority = READ_ONCE(ifa->rt_priority);
5187 	if (priority && nla_put_u32(skb, IFA_RT_PRIORITY, priority))
5188 		goto error;
5189 
5190 	if (put_cacheinfo(skb, ifa->cstamp, READ_ONCE(ifa->tstamp),
5191 			  preferred, valid) < 0)
5192 		goto error;
5193 
5194 	if (nla_put_u32(skb, IFA_FLAGS, flags) < 0)
5195 		goto error;
5196 
5197 	proto = READ_ONCE(ifa->ifa_proto);
5198 	if (proto && nla_put_u8(skb, IFA_PROTO, proto))
5199 		goto error;
5200 
5201 	nlmsg_end(skb, nlh);
5202 	return 0;
5203 
5204 error:
5205 	nlmsg_cancel(skb, nlh);
5206 	return -EMSGSIZE;
5207 }
5208 
5209 static int inet6_fill_ifmcaddr(struct sk_buff *skb,
5210 			       const struct ifmcaddr6 *ifmca,
5211 			       struct inet6_fill_args *args)
5212 {
5213 	int ifindex = ifmca->idev->dev->ifindex;
5214 	u8 scope = RT_SCOPE_UNIVERSE;
5215 	struct nlmsghdr *nlh;
5216 
5217 	if (ipv6_addr_scope(&ifmca->mca_addr) & IFA_SITE)
5218 		scope = RT_SCOPE_SITE;
5219 
5220 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5221 			sizeof(struct ifaddrmsg), args->flags);
5222 	if (!nlh)
5223 		return -EMSGSIZE;
5224 
5225 	if (args->netnsid >= 0 &&
5226 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) {
5227 		nlmsg_cancel(skb, nlh);
5228 		return -EMSGSIZE;
5229 	}
5230 
5231 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5232 	if (nla_put_in6_addr(skb, IFA_MULTICAST, &ifmca->mca_addr) < 0 ||
5233 	    put_cacheinfo(skb, ifmca->mca_cstamp, READ_ONCE(ifmca->mca_tstamp),
5234 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5235 		nlmsg_cancel(skb, nlh);
5236 		return -EMSGSIZE;
5237 	}
5238 
5239 	nlmsg_end(skb, nlh);
5240 	return 0;
5241 }
5242 
5243 static int inet6_fill_ifacaddr(struct sk_buff *skb,
5244 			       const struct ifacaddr6 *ifaca,
5245 			       struct inet6_fill_args *args)
5246 {
5247 	struct net_device *dev = fib6_info_nh_dev(ifaca->aca_rt);
5248 	int ifindex = dev ? dev->ifindex : 1;
5249 	u8 scope = RT_SCOPE_UNIVERSE;
5250 	struct nlmsghdr *nlh;
5251 
5252 	if (ipv6_addr_scope(&ifaca->aca_addr) & IFA_SITE)
5253 		scope = RT_SCOPE_SITE;
5254 
5255 	nlh = nlmsg_put(skb, args->portid, args->seq, args->event,
5256 			sizeof(struct ifaddrmsg), args->flags);
5257 	if (!nlh)
5258 		return -EMSGSIZE;
5259 
5260 	if (args->netnsid >= 0 &&
5261 	    nla_put_s32(skb, IFA_TARGET_NETNSID, args->netnsid)) {
5262 		nlmsg_cancel(skb, nlh);
5263 		return -EMSGSIZE;
5264 	}
5265 
5266 	put_ifaddrmsg(nlh, 128, IFA_F_PERMANENT, scope, ifindex);
5267 	if (nla_put_in6_addr(skb, IFA_ANYCAST, &ifaca->aca_addr) < 0 ||
5268 	    put_cacheinfo(skb, ifaca->aca_cstamp, READ_ONCE(ifaca->aca_tstamp),
5269 			  INFINITY_LIFE_TIME, INFINITY_LIFE_TIME) < 0) {
5270 		nlmsg_cancel(skb, nlh);
5271 		return -EMSGSIZE;
5272 	}
5273 
5274 	nlmsg_end(skb, nlh);
5275 	return 0;
5276 }
5277 
5278 /* called with rcu_read_lock() */
5279 static int in6_dump_addrs(const struct inet6_dev *idev, struct sk_buff *skb,
5280 			  struct netlink_callback *cb, int *s_ip_idx,
5281 			  struct inet6_fill_args *fillargs)
5282 {
5283 	const struct ifmcaddr6 *ifmca;
5284 	const struct ifacaddr6 *ifaca;
5285 	int ip_idx = 0;
5286 	int err = 0;
5287 
5288 	switch (fillargs->type) {
5289 	case UNICAST_ADDR: {
5290 		const struct inet6_ifaddr *ifa;
5291 		fillargs->event = RTM_NEWADDR;
5292 
5293 		/* unicast address incl. temp addr */
5294 		list_for_each_entry_rcu(ifa, &idev->addr_list, if_list) {
5295 			if (ip_idx < *s_ip_idx)
5296 				goto next;
5297 			err = inet6_fill_ifaddr(skb, ifa, fillargs);
5298 			if (err < 0)
5299 				break;
5300 			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
5301 next:
5302 			ip_idx++;
5303 		}
5304 		break;
5305 	}
5306 	case MULTICAST_ADDR:
5307 		fillargs->event = RTM_GETMULTICAST;
5308 
5309 		/* multicast address */
5310 		for (ifmca = rcu_dereference(idev->mc_list);
5311 		     ifmca;
5312 		     ifmca = rcu_dereference(ifmca->next), ip_idx++) {
5313 			if (ip_idx < *s_ip_idx)
5314 				continue;
5315 			err = inet6_fill_ifmcaddr(skb, ifmca, fillargs);
5316 			if (err < 0)
5317 				break;
5318 		}
5319 		break;
5320 	case ANYCAST_ADDR:
5321 		fillargs->event = RTM_GETANYCAST;
5322 		/* anycast address */
5323 		for (ifaca = rcu_dereference(idev->ac_list); ifaca;
5324 		     ifaca = rcu_dereference(ifaca->aca_next), ip_idx++) {
5325 			if (ip_idx < *s_ip_idx)
5326 				continue;
5327 			err = inet6_fill_ifacaddr(skb, ifaca, fillargs);
5328 			if (err < 0)
5329 				break;
5330 		}
5331 		break;
5332 	default:
5333 		break;
5334 	}
5335 	*s_ip_idx = err ? ip_idx : 0;
5336 	return err;
5337 }
5338 
5339 static int inet6_valid_dump_ifaddr_req(const struct nlmsghdr *nlh,
5340 				       struct inet6_fill_args *fillargs,
5341 				       struct net **tgt_net, struct sock *sk,
5342 				       struct netlink_callback *cb)
5343 {
5344 	struct netlink_ext_ack *extack = cb->extack;
5345 	struct nlattr *tb[IFA_MAX+1];
5346 	struct ifaddrmsg *ifm;
5347 	int err, i;
5348 
5349 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5350 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for address dump request");
5351 		return -EINVAL;
5352 	}
5353 
5354 	ifm = nlmsg_data(nlh);
5355 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5356 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for address dump request");
5357 		return -EINVAL;
5358 	}
5359 
5360 	fillargs->ifindex = ifm->ifa_index;
5361 	if (fillargs->ifindex) {
5362 		cb->answer_flags |= NLM_F_DUMP_FILTERED;
5363 		fillargs->flags |= NLM_F_DUMP_FILTERED;
5364 	}
5365 
5366 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5367 					    ifa_ipv6_policy, extack);
5368 	if (err < 0)
5369 		return err;
5370 
5371 	for (i = 0; i <= IFA_MAX; ++i) {
5372 		if (!tb[i])
5373 			continue;
5374 
5375 		if (i == IFA_TARGET_NETNSID) {
5376 			struct net *net;
5377 
5378 			fillargs->netnsid = nla_get_s32(tb[i]);
5379 			net = rtnl_get_net_ns_capable(sk, fillargs->netnsid);
5380 			if (IS_ERR(net)) {
5381 				fillargs->netnsid = -1;
5382 				NL_SET_ERR_MSG_MOD(extack, "Invalid target network namespace id");
5383 				return PTR_ERR(net);
5384 			}
5385 			*tgt_net = net;
5386 		} else {
5387 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in dump request");
5388 			return -EINVAL;
5389 		}
5390 	}
5391 
5392 	return 0;
5393 }
5394 
5395 static int inet6_dump_addr(struct sk_buff *skb, struct netlink_callback *cb,
5396 			   enum addr_type_t type)
5397 {
5398 	struct net *tgt_net = sock_net(skb->sk);
5399 	const struct nlmsghdr *nlh = cb->nlh;
5400 	struct inet6_fill_args fillargs = {
5401 		.portid = NETLINK_CB(cb->skb).portid,
5402 		.seq = cb->nlh->nlmsg_seq,
5403 		.flags = NLM_F_MULTI,
5404 		.netnsid = -1,
5405 		.type = type,
5406 	};
5407 	struct {
5408 		unsigned long ifindex;
5409 		int ip_idx;
5410 	} *ctx = (void *)cb->ctx;
5411 	struct net_device *dev;
5412 	struct inet6_dev *idev;
5413 	int err = 0;
5414 
5415 	rcu_read_lock();
5416 	if (cb->strict_check) {
5417 		err = inet6_valid_dump_ifaddr_req(nlh, &fillargs, &tgt_net,
5418 						  skb->sk, cb);
5419 		if (err < 0)
5420 			goto done;
5421 
5422 		err = 0;
5423 		if (fillargs.ifindex) {
5424 			dev = dev_get_by_index_rcu(tgt_net, fillargs.ifindex);
5425 			if (!dev) {
5426 				err = -ENODEV;
5427 				goto done;
5428 			}
5429 			idev = __in6_dev_get(dev);
5430 			if (idev)
5431 				err = in6_dump_addrs(idev, skb, cb,
5432 						     &ctx->ip_idx,
5433 						     &fillargs);
5434 			goto done;
5435 		}
5436 	}
5437 
5438 	cb->seq = inet6_base_seq(tgt_net);
5439 	for_each_netdev_dump(tgt_net, dev, ctx->ifindex) {
5440 		idev = __in6_dev_get(dev);
5441 		if (!idev)
5442 			continue;
5443 		err = in6_dump_addrs(idev, skb, cb, &ctx->ip_idx,
5444 				     &fillargs);
5445 		if (err < 0)
5446 			goto done;
5447 	}
5448 done:
5449 	rcu_read_unlock();
5450 	if (fillargs.netnsid >= 0)
5451 		put_net(tgt_net);
5452 
5453 	return err;
5454 }
5455 
5456 static int inet6_dump_ifaddr(struct sk_buff *skb, struct netlink_callback *cb)
5457 {
5458 	enum addr_type_t type = UNICAST_ADDR;
5459 
5460 	return inet6_dump_addr(skb, cb, type);
5461 }
5462 
5463 static int inet6_dump_ifmcaddr(struct sk_buff *skb, struct netlink_callback *cb)
5464 {
5465 	enum addr_type_t type = MULTICAST_ADDR;
5466 
5467 	return inet6_dump_addr(skb, cb, type);
5468 }
5469 
5470 
5471 static int inet6_dump_ifacaddr(struct sk_buff *skb, struct netlink_callback *cb)
5472 {
5473 	enum addr_type_t type = ANYCAST_ADDR;
5474 
5475 	return inet6_dump_addr(skb, cb, type);
5476 }
5477 
5478 static int inet6_rtm_valid_getaddr_req(struct sk_buff *skb,
5479 				       const struct nlmsghdr *nlh,
5480 				       struct nlattr **tb,
5481 				       struct netlink_ext_ack *extack)
5482 {
5483 	struct ifaddrmsg *ifm;
5484 	int i, err;
5485 
5486 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
5487 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for get address request");
5488 		return -EINVAL;
5489 	}
5490 
5491 	if (!netlink_strict_get_check(skb))
5492 		return nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFA_MAX,
5493 					      ifa_ipv6_policy, extack);
5494 
5495 	ifm = nlmsg_data(nlh);
5496 	if (ifm->ifa_prefixlen || ifm->ifa_flags || ifm->ifa_scope) {
5497 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for get address request");
5498 		return -EINVAL;
5499 	}
5500 
5501 	err = nlmsg_parse_deprecated_strict(nlh, sizeof(*ifm), tb, IFA_MAX,
5502 					    ifa_ipv6_policy, extack);
5503 	if (err)
5504 		return err;
5505 
5506 	for (i = 0; i <= IFA_MAX; i++) {
5507 		if (!tb[i])
5508 			continue;
5509 
5510 		switch (i) {
5511 		case IFA_TARGET_NETNSID:
5512 		case IFA_ADDRESS:
5513 		case IFA_LOCAL:
5514 			break;
5515 		default:
5516 			NL_SET_ERR_MSG_MOD(extack, "Unsupported attribute in get address request");
5517 			return -EINVAL;
5518 		}
5519 	}
5520 
5521 	return 0;
5522 }
5523 
5524 static int inet6_rtm_getaddr(struct sk_buff *in_skb, struct nlmsghdr *nlh,
5525 			     struct netlink_ext_ack *extack)
5526 {
5527 	struct net *tgt_net = sock_net(in_skb->sk);
5528 	struct inet6_fill_args fillargs = {
5529 		.portid = NETLINK_CB(in_skb).portid,
5530 		.seq = nlh->nlmsg_seq,
5531 		.event = RTM_NEWADDR,
5532 		.flags = 0,
5533 		.netnsid = -1,
5534 	};
5535 	struct ifaddrmsg *ifm;
5536 	struct nlattr *tb[IFA_MAX+1];
5537 	struct in6_addr *addr = NULL, *peer;
5538 	struct net_device *dev = NULL;
5539 	struct inet6_ifaddr *ifa;
5540 	struct sk_buff *skb;
5541 	int err;
5542 
5543 	err = inet6_rtm_valid_getaddr_req(in_skb, nlh, tb, extack);
5544 	if (err < 0)
5545 		return err;
5546 
5547 	if (tb[IFA_TARGET_NETNSID]) {
5548 		fillargs.netnsid = nla_get_s32(tb[IFA_TARGET_NETNSID]);
5549 
5550 		tgt_net = rtnl_get_net_ns_capable(NETLINK_CB(in_skb).sk,
5551 						  fillargs.netnsid);
5552 		if (IS_ERR(tgt_net))
5553 			return PTR_ERR(tgt_net);
5554 	}
5555 
5556 	addr = extract_addr(tb[IFA_ADDRESS], tb[IFA_LOCAL], &peer);
5557 	if (!addr) {
5558 		err = -EINVAL;
5559 		goto errout;
5560 	}
5561 	ifm = nlmsg_data(nlh);
5562 	if (ifm->ifa_index)
5563 		dev = dev_get_by_index(tgt_net, ifm->ifa_index);
5564 
5565 	ifa = ipv6_get_ifaddr(tgt_net, addr, dev, 1);
5566 	if (!ifa) {
5567 		err = -EADDRNOTAVAIL;
5568 		goto errout;
5569 	}
5570 
5571 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_KERNEL);
5572 	if (!skb) {
5573 		err = -ENOBUFS;
5574 		goto errout_ifa;
5575 	}
5576 
5577 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5578 	if (err < 0) {
5579 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5580 		WARN_ON(err == -EMSGSIZE);
5581 		kfree_skb(skb);
5582 		goto errout_ifa;
5583 	}
5584 	err = rtnl_unicast(skb, tgt_net, NETLINK_CB(in_skb).portid);
5585 errout_ifa:
5586 	in6_ifa_put(ifa);
5587 errout:
5588 	dev_put(dev);
5589 	if (fillargs.netnsid >= 0)
5590 		put_net(tgt_net);
5591 
5592 	return err;
5593 }
5594 
5595 static void inet6_ifa_notify(int event, struct inet6_ifaddr *ifa)
5596 {
5597 	struct sk_buff *skb;
5598 	struct net *net = dev_net(ifa->idev->dev);
5599 	struct inet6_fill_args fillargs = {
5600 		.portid = 0,
5601 		.seq = 0,
5602 		.event = event,
5603 		.flags = 0,
5604 		.netnsid = -1,
5605 	};
5606 	int err = -ENOBUFS;
5607 
5608 	skb = nlmsg_new(inet6_ifaddr_msgsize(), GFP_ATOMIC);
5609 	if (!skb)
5610 		goto errout;
5611 
5612 	err = inet6_fill_ifaddr(skb, ifa, &fillargs);
5613 	if (err < 0) {
5614 		/* -EMSGSIZE implies BUG in inet6_ifaddr_msgsize() */
5615 		WARN_ON(err == -EMSGSIZE);
5616 		kfree_skb(skb);
5617 		goto errout;
5618 	}
5619 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFADDR, NULL, GFP_ATOMIC);
5620 	return;
5621 errout:
5622 	rtnl_set_sk_err(net, RTNLGRP_IPV6_IFADDR, err);
5623 }
5624 
5625 static void ipv6_store_devconf(const struct ipv6_devconf *cnf,
5626 			       __s32 *array, int bytes)
5627 {
5628 	BUG_ON(bytes < (DEVCONF_MAX * 4));
5629 
5630 	memset(array, 0, bytes);
5631 	array[DEVCONF_FORWARDING] = READ_ONCE(cnf->forwarding);
5632 	array[DEVCONF_HOPLIMIT] = READ_ONCE(cnf->hop_limit);
5633 	array[DEVCONF_MTU6] = READ_ONCE(cnf->mtu6);
5634 	array[DEVCONF_ACCEPT_RA] = READ_ONCE(cnf->accept_ra);
5635 	array[DEVCONF_ACCEPT_REDIRECTS] = READ_ONCE(cnf->accept_redirects);
5636 	array[DEVCONF_AUTOCONF] = READ_ONCE(cnf->autoconf);
5637 	array[DEVCONF_DAD_TRANSMITS] = READ_ONCE(cnf->dad_transmits);
5638 	array[DEVCONF_RTR_SOLICITS] = READ_ONCE(cnf->rtr_solicits);
5639 	array[DEVCONF_RTR_SOLICIT_INTERVAL] =
5640 		jiffies_to_msecs(READ_ONCE(cnf->rtr_solicit_interval));
5641 	array[DEVCONF_RTR_SOLICIT_MAX_INTERVAL] =
5642 		jiffies_to_msecs(READ_ONCE(cnf->rtr_solicit_max_interval));
5643 	array[DEVCONF_RTR_SOLICIT_DELAY] =
5644 		jiffies_to_msecs(READ_ONCE(cnf->rtr_solicit_delay));
5645 	array[DEVCONF_FORCE_MLD_VERSION] = READ_ONCE(cnf->force_mld_version);
5646 	array[DEVCONF_MLDV1_UNSOLICITED_REPORT_INTERVAL] =
5647 		jiffies_to_msecs(READ_ONCE(cnf->mldv1_unsolicited_report_interval));
5648 	array[DEVCONF_MLDV2_UNSOLICITED_REPORT_INTERVAL] =
5649 		jiffies_to_msecs(READ_ONCE(cnf->mldv2_unsolicited_report_interval));
5650 	array[DEVCONF_USE_TEMPADDR] = READ_ONCE(cnf->use_tempaddr);
5651 	array[DEVCONF_TEMP_VALID_LFT] = READ_ONCE(cnf->temp_valid_lft);
5652 	array[DEVCONF_TEMP_PREFERED_LFT] = READ_ONCE(cnf->temp_prefered_lft);
5653 	array[DEVCONF_REGEN_MAX_RETRY] = READ_ONCE(cnf->regen_max_retry);
5654 	array[DEVCONF_MAX_DESYNC_FACTOR] = READ_ONCE(cnf->max_desync_factor);
5655 	array[DEVCONF_MAX_ADDRESSES] = READ_ONCE(cnf->max_addresses);
5656 	array[DEVCONF_ACCEPT_RA_DEFRTR] = READ_ONCE(cnf->accept_ra_defrtr);
5657 	array[DEVCONF_RA_DEFRTR_METRIC] = READ_ONCE(cnf->ra_defrtr_metric);
5658 	array[DEVCONF_ACCEPT_RA_MIN_HOP_LIMIT] =
5659 		READ_ONCE(cnf->accept_ra_min_hop_limit);
5660 	array[DEVCONF_ACCEPT_RA_PINFO] = READ_ONCE(cnf->accept_ra_pinfo);
5661 #ifdef CONFIG_IPV6_ROUTER_PREF
5662 	array[DEVCONF_ACCEPT_RA_RTR_PREF] = READ_ONCE(cnf->accept_ra_rtr_pref);
5663 	array[DEVCONF_RTR_PROBE_INTERVAL] =
5664 		jiffies_to_msecs(READ_ONCE(cnf->rtr_probe_interval));
5665 #ifdef CONFIG_IPV6_ROUTE_INFO
5666 	array[DEVCONF_ACCEPT_RA_RT_INFO_MIN_PLEN] =
5667 		READ_ONCE(cnf->accept_ra_rt_info_min_plen);
5668 	array[DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN] =
5669 		READ_ONCE(cnf->accept_ra_rt_info_max_plen);
5670 #endif
5671 #endif
5672 	array[DEVCONF_PROXY_NDP] = READ_ONCE(cnf->proxy_ndp);
5673 	array[DEVCONF_ACCEPT_SOURCE_ROUTE] =
5674 		READ_ONCE(cnf->accept_source_route);
5675 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
5676 	array[DEVCONF_OPTIMISTIC_DAD] = READ_ONCE(cnf->optimistic_dad);
5677 	array[DEVCONF_USE_OPTIMISTIC] = READ_ONCE(cnf->use_optimistic);
5678 #endif
5679 #ifdef CONFIG_IPV6_MROUTE
5680 	array[DEVCONF_MC_FORWARDING] = atomic_read(&cnf->mc_forwarding);
5681 #endif
5682 	array[DEVCONF_DISABLE_IPV6] = READ_ONCE(cnf->disable_ipv6);
5683 	array[DEVCONF_ACCEPT_DAD] = READ_ONCE(cnf->accept_dad);
5684 	array[DEVCONF_FORCE_TLLAO] = READ_ONCE(cnf->force_tllao);
5685 	array[DEVCONF_NDISC_NOTIFY] = READ_ONCE(cnf->ndisc_notify);
5686 	array[DEVCONF_SUPPRESS_FRAG_NDISC] =
5687 		READ_ONCE(cnf->suppress_frag_ndisc);
5688 	array[DEVCONF_ACCEPT_RA_FROM_LOCAL] =
5689 		READ_ONCE(cnf->accept_ra_from_local);
5690 	array[DEVCONF_ACCEPT_RA_MTU] = READ_ONCE(cnf->accept_ra_mtu);
5691 	array[DEVCONF_IGNORE_ROUTES_WITH_LINKDOWN] =
5692 		READ_ONCE(cnf->ignore_routes_with_linkdown);
5693 	/* we omit DEVCONF_STABLE_SECRET for now */
5694 	array[DEVCONF_USE_OIF_ADDRS_ONLY] = READ_ONCE(cnf->use_oif_addrs_only);
5695 	array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] =
5696 		READ_ONCE(cnf->drop_unicast_in_l2_multicast);
5697 	array[DEVCONF_DROP_UNSOLICITED_NA] = READ_ONCE(cnf->drop_unsolicited_na);
5698 	array[DEVCONF_KEEP_ADDR_ON_DOWN] = READ_ONCE(cnf->keep_addr_on_down);
5699 	array[DEVCONF_SEG6_ENABLED] = READ_ONCE(cnf->seg6_enabled);
5700 #ifdef CONFIG_IPV6_SEG6_HMAC
5701 	array[DEVCONF_SEG6_REQUIRE_HMAC] = READ_ONCE(cnf->seg6_require_hmac);
5702 #endif
5703 	array[DEVCONF_ENHANCED_DAD] = READ_ONCE(cnf->enhanced_dad);
5704 	array[DEVCONF_ADDR_GEN_MODE] = READ_ONCE(cnf->addr_gen_mode);
5705 	array[DEVCONF_DISABLE_POLICY] = READ_ONCE(cnf->disable_policy);
5706 	array[DEVCONF_NDISC_TCLASS] = READ_ONCE(cnf->ndisc_tclass);
5707 	array[DEVCONF_RPL_SEG_ENABLED] = READ_ONCE(cnf->rpl_seg_enabled);
5708 	array[DEVCONF_IOAM6_ENABLED] = READ_ONCE(cnf->ioam6_enabled);
5709 	array[DEVCONF_IOAM6_ID] = READ_ONCE(cnf->ioam6_id);
5710 	array[DEVCONF_IOAM6_ID_WIDE] = READ_ONCE(cnf->ioam6_id_wide);
5711 	array[DEVCONF_NDISC_EVICT_NOCARRIER] =
5712 		READ_ONCE(cnf->ndisc_evict_nocarrier);
5713 	array[DEVCONF_ACCEPT_UNTRACKED_NA] =
5714 		READ_ONCE(cnf->accept_untracked_na);
5715 	array[DEVCONF_ACCEPT_RA_MIN_LFT] = READ_ONCE(cnf->accept_ra_min_lft);
5716 }
5717 
5718 static inline size_t inet6_ifla6_size(void)
5719 {
5720 	return nla_total_size(4) /* IFLA_INET6_FLAGS */
5721 	     + nla_total_size(sizeof(struct ifla_cacheinfo))
5722 	     + nla_total_size(DEVCONF_MAX * 4) /* IFLA_INET6_CONF */
5723 	     + nla_total_size(IPSTATS_MIB_MAX * 8) /* IFLA_INET6_STATS */
5724 	     + nla_total_size(ICMP6_MIB_MAX * 8) /* IFLA_INET6_ICMP6STATS */
5725 	     + nla_total_size(sizeof(struct in6_addr)) /* IFLA_INET6_TOKEN */
5726 	     + nla_total_size(1) /* IFLA_INET6_ADDR_GEN_MODE */
5727 	     + nla_total_size(4) /* IFLA_INET6_RA_MTU */
5728 	     + 0;
5729 }
5730 
5731 static inline size_t inet6_if_nlmsg_size(void)
5732 {
5733 	return NLMSG_ALIGN(sizeof(struct ifinfomsg))
5734 	       + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */
5735 	       + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */
5736 	       + nla_total_size(4) /* IFLA_MTU */
5737 	       + nla_total_size(4) /* IFLA_LINK */
5738 	       + nla_total_size(1) /* IFLA_OPERSTATE */
5739 	       + nla_total_size(inet6_ifla6_size()); /* IFLA_PROTINFO */
5740 }
5741 
5742 static inline void __snmp6_fill_statsdev(u64 *stats, atomic_long_t *mib,
5743 					int bytes)
5744 {
5745 	int i;
5746 	int pad = bytes - sizeof(u64) * ICMP6_MIB_MAX;
5747 	BUG_ON(pad < 0);
5748 
5749 	/* Use put_unaligned() because stats may not be aligned for u64. */
5750 	put_unaligned(ICMP6_MIB_MAX, &stats[0]);
5751 	for (i = 1; i < ICMP6_MIB_MAX; i++)
5752 		put_unaligned(atomic_long_read(&mib[i]), &stats[i]);
5753 
5754 	memset(&stats[ICMP6_MIB_MAX], 0, pad);
5755 }
5756 
5757 static inline void __snmp6_fill_stats64(u64 *stats, void __percpu *mib,
5758 					int bytes, size_t syncpoff)
5759 {
5760 	int i, c;
5761 	u64 buff[IPSTATS_MIB_MAX];
5762 	int pad = bytes - sizeof(u64) * IPSTATS_MIB_MAX;
5763 
5764 	BUG_ON(pad < 0);
5765 
5766 	memset(buff, 0, sizeof(buff));
5767 	buff[0] = IPSTATS_MIB_MAX;
5768 
5769 	for_each_possible_cpu(c) {
5770 		for (i = 1; i < IPSTATS_MIB_MAX; i++)
5771 			buff[i] += snmp_get_cpu_field64(mib, c, i, syncpoff);
5772 	}
5773 
5774 	memcpy(stats, buff, IPSTATS_MIB_MAX * sizeof(u64));
5775 	memset(&stats[IPSTATS_MIB_MAX], 0, pad);
5776 }
5777 
5778 static void snmp6_fill_stats(u64 *stats, struct inet6_dev *idev, int attrtype,
5779 			     int bytes)
5780 {
5781 	switch (attrtype) {
5782 	case IFLA_INET6_STATS:
5783 		__snmp6_fill_stats64(stats, idev->stats.ipv6, bytes,
5784 				     offsetof(struct ipstats_mib, syncp));
5785 		break;
5786 	case IFLA_INET6_ICMP6STATS:
5787 		__snmp6_fill_statsdev(stats, idev->stats.icmpv6dev->mibs, bytes);
5788 		break;
5789 	}
5790 }
5791 
5792 static int inet6_fill_ifla6_attrs(struct sk_buff *skb, struct inet6_dev *idev,
5793 				  u32 ext_filter_mask)
5794 {
5795 	struct ifla_cacheinfo ci;
5796 	struct nlattr *nla;
5797 	u32 ra_mtu;
5798 
5799 	if (nla_put_u32(skb, IFLA_INET6_FLAGS, READ_ONCE(idev->if_flags)))
5800 		goto nla_put_failure;
5801 	ci.max_reasm_len = IPV6_MAXPLEN;
5802 	ci.tstamp = cstamp_delta(READ_ONCE(idev->tstamp));
5803 	ci.reachable_time = jiffies_to_msecs(idev->nd_parms->reachable_time);
5804 	ci.retrans_time = jiffies_to_msecs(NEIGH_VAR(idev->nd_parms, RETRANS_TIME));
5805 	if (nla_put(skb, IFLA_INET6_CACHEINFO, sizeof(ci), &ci))
5806 		goto nla_put_failure;
5807 	nla = nla_reserve(skb, IFLA_INET6_CONF, DEVCONF_MAX * sizeof(s32));
5808 	if (!nla)
5809 		goto nla_put_failure;
5810 	ipv6_store_devconf(&idev->cnf, nla_data(nla), nla_len(nla));
5811 
5812 	/* XXX - MC not implemented */
5813 
5814 	if (ext_filter_mask & RTEXT_FILTER_SKIP_STATS)
5815 		return 0;
5816 
5817 	nla = nla_reserve(skb, IFLA_INET6_STATS, IPSTATS_MIB_MAX * sizeof(u64));
5818 	if (!nla)
5819 		goto nla_put_failure;
5820 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_STATS, nla_len(nla));
5821 
5822 	nla = nla_reserve(skb, IFLA_INET6_ICMP6STATS, ICMP6_MIB_MAX * sizeof(u64));
5823 	if (!nla)
5824 		goto nla_put_failure;
5825 	snmp6_fill_stats(nla_data(nla), idev, IFLA_INET6_ICMP6STATS, nla_len(nla));
5826 
5827 	nla = nla_reserve(skb, IFLA_INET6_TOKEN, sizeof(struct in6_addr));
5828 	if (!nla)
5829 		goto nla_put_failure;
5830 	read_lock_bh(&idev->lock);
5831 	memcpy(nla_data(nla), idev->token.s6_addr, nla_len(nla));
5832 	read_unlock_bh(&idev->lock);
5833 
5834 	if (nla_put_u8(skb, IFLA_INET6_ADDR_GEN_MODE,
5835 		       READ_ONCE(idev->cnf.addr_gen_mode)))
5836 		goto nla_put_failure;
5837 
5838 	ra_mtu = READ_ONCE(idev->ra_mtu);
5839 	if (ra_mtu && nla_put_u32(skb, IFLA_INET6_RA_MTU, ra_mtu))
5840 		goto nla_put_failure;
5841 
5842 	return 0;
5843 
5844 nla_put_failure:
5845 	return -EMSGSIZE;
5846 }
5847 
5848 static size_t inet6_get_link_af_size(const struct net_device *dev,
5849 				     u32 ext_filter_mask)
5850 {
5851 	if (!__in6_dev_get(dev))
5852 		return 0;
5853 
5854 	return inet6_ifla6_size();
5855 }
5856 
5857 static int inet6_fill_link_af(struct sk_buff *skb, const struct net_device *dev,
5858 			      u32 ext_filter_mask)
5859 {
5860 	struct inet6_dev *idev = __in6_dev_get(dev);
5861 
5862 	if (!idev)
5863 		return -ENODATA;
5864 
5865 	if (inet6_fill_ifla6_attrs(skb, idev, ext_filter_mask) < 0)
5866 		return -EMSGSIZE;
5867 
5868 	return 0;
5869 }
5870 
5871 static int inet6_set_iftoken(struct inet6_dev *idev, struct in6_addr *token,
5872 			     struct netlink_ext_ack *extack)
5873 {
5874 	struct inet6_ifaddr *ifp;
5875 	struct net_device *dev = idev->dev;
5876 	bool clear_token, update_rs = false;
5877 	struct in6_addr ll_addr;
5878 
5879 	ASSERT_RTNL();
5880 
5881 	if (!token)
5882 		return -EINVAL;
5883 
5884 	if (dev->flags & IFF_LOOPBACK) {
5885 		NL_SET_ERR_MSG_MOD(extack, "Device is loopback");
5886 		return -EINVAL;
5887 	}
5888 
5889 	if (dev->flags & IFF_NOARP) {
5890 		NL_SET_ERR_MSG_MOD(extack,
5891 				   "Device does not do neighbour discovery");
5892 		return -EINVAL;
5893 	}
5894 
5895 	if (!ipv6_accept_ra(idev)) {
5896 		NL_SET_ERR_MSG_MOD(extack,
5897 				   "Router advertisement is disabled on device");
5898 		return -EINVAL;
5899 	}
5900 
5901 	if (READ_ONCE(idev->cnf.rtr_solicits) == 0) {
5902 		NL_SET_ERR_MSG(extack,
5903 			       "Router solicitation is disabled on device");
5904 		return -EINVAL;
5905 	}
5906 
5907 	write_lock_bh(&idev->lock);
5908 
5909 	BUILD_BUG_ON(sizeof(token->s6_addr) != 16);
5910 	memcpy(idev->token.s6_addr + 8, token->s6_addr + 8, 8);
5911 
5912 	write_unlock_bh(&idev->lock);
5913 
5914 	clear_token = ipv6_addr_any(token);
5915 	if (clear_token)
5916 		goto update_lft;
5917 
5918 	if (!idev->dead && (idev->if_flags & IF_READY) &&
5919 	    !ipv6_get_lladdr(dev, &ll_addr, IFA_F_TENTATIVE |
5920 			     IFA_F_OPTIMISTIC)) {
5921 		/* If we're not ready, then normal ifup will take care
5922 		 * of this. Otherwise, we need to request our rs here.
5923 		 */
5924 		ndisc_send_rs(dev, &ll_addr, &in6addr_linklocal_allrouters);
5925 		update_rs = true;
5926 	}
5927 
5928 update_lft:
5929 	write_lock_bh(&idev->lock);
5930 
5931 	if (update_rs) {
5932 		idev->if_flags |= IF_RS_SENT;
5933 		idev->rs_interval = rfc3315_s14_backoff_init(
5934 			READ_ONCE(idev->cnf.rtr_solicit_interval));
5935 		idev->rs_probes = 1;
5936 		addrconf_mod_rs_timer(idev, idev->rs_interval);
5937 	}
5938 
5939 	/* Well, that's kinda nasty ... */
5940 	list_for_each_entry(ifp, &idev->addr_list, if_list) {
5941 		spin_lock(&ifp->lock);
5942 		if (ifp->tokenized) {
5943 			ifp->valid_lft = 0;
5944 			ifp->prefered_lft = 0;
5945 		}
5946 		spin_unlock(&ifp->lock);
5947 	}
5948 
5949 	write_unlock_bh(&idev->lock);
5950 	inet6_ifinfo_notify(RTM_NEWLINK, idev);
5951 	addrconf_verify_rtnl(dev_net(dev));
5952 	return 0;
5953 }
5954 
5955 static const struct nla_policy inet6_af_policy[IFLA_INET6_MAX + 1] = {
5956 	[IFLA_INET6_ADDR_GEN_MODE]	= { .type = NLA_U8 },
5957 	[IFLA_INET6_TOKEN]		= { .len = sizeof(struct in6_addr) },
5958 	[IFLA_INET6_RA_MTU]		= { .type = NLA_REJECT,
5959 					    .reject_message =
5960 						"IFLA_INET6_RA_MTU can not be set" },
5961 };
5962 
5963 static int check_addr_gen_mode(int mode)
5964 {
5965 	if (mode != IN6_ADDR_GEN_MODE_EUI64 &&
5966 	    mode != IN6_ADDR_GEN_MODE_NONE &&
5967 	    mode != IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5968 	    mode != IN6_ADDR_GEN_MODE_RANDOM)
5969 		return -EINVAL;
5970 	return 1;
5971 }
5972 
5973 static int check_stable_privacy(struct inet6_dev *idev, struct net *net,
5974 				int mode)
5975 {
5976 	if (mode == IN6_ADDR_GEN_MODE_STABLE_PRIVACY &&
5977 	    !idev->cnf.stable_secret.initialized &&
5978 	    !net->ipv6.devconf_dflt->stable_secret.initialized)
5979 		return -EINVAL;
5980 	return 1;
5981 }
5982 
5983 static int inet6_validate_link_af(const struct net_device *dev,
5984 				  const struct nlattr *nla,
5985 				  struct netlink_ext_ack *extack)
5986 {
5987 	struct nlattr *tb[IFLA_INET6_MAX + 1];
5988 	struct inet6_dev *idev = NULL;
5989 	int err;
5990 
5991 	if (dev) {
5992 		idev = __in6_dev_get(dev);
5993 		if (!idev)
5994 			return -EAFNOSUPPORT;
5995 	}
5996 
5997 	err = nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla,
5998 					  inet6_af_policy, extack);
5999 	if (err)
6000 		return err;
6001 
6002 	if (!tb[IFLA_INET6_TOKEN] && !tb[IFLA_INET6_ADDR_GEN_MODE])
6003 		return -EINVAL;
6004 
6005 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
6006 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
6007 
6008 		if (check_addr_gen_mode(mode) < 0)
6009 			return -EINVAL;
6010 		if (dev && check_stable_privacy(idev, dev_net(dev), mode) < 0)
6011 			return -EINVAL;
6012 	}
6013 
6014 	return 0;
6015 }
6016 
6017 static int inet6_set_link_af(struct net_device *dev, const struct nlattr *nla,
6018 			     struct netlink_ext_ack *extack)
6019 {
6020 	struct inet6_dev *idev = __in6_dev_get(dev);
6021 	struct nlattr *tb[IFLA_INET6_MAX + 1];
6022 	int err;
6023 
6024 	if (!idev)
6025 		return -EAFNOSUPPORT;
6026 
6027 	if (nla_parse_nested_deprecated(tb, IFLA_INET6_MAX, nla, NULL, NULL) < 0)
6028 		return -EINVAL;
6029 
6030 	if (tb[IFLA_INET6_TOKEN]) {
6031 		err = inet6_set_iftoken(idev, nla_data(tb[IFLA_INET6_TOKEN]),
6032 					extack);
6033 		if (err)
6034 			return err;
6035 	}
6036 
6037 	if (tb[IFLA_INET6_ADDR_GEN_MODE]) {
6038 		u8 mode = nla_get_u8(tb[IFLA_INET6_ADDR_GEN_MODE]);
6039 
6040 		WRITE_ONCE(idev->cnf.addr_gen_mode, mode);
6041 	}
6042 
6043 	return 0;
6044 }
6045 
6046 static int inet6_fill_ifinfo(struct sk_buff *skb, struct inet6_dev *idev,
6047 			     u32 portid, u32 seq, int event, unsigned int flags)
6048 {
6049 	struct net_device *dev = idev->dev;
6050 	struct ifinfomsg *hdr;
6051 	struct nlmsghdr *nlh;
6052 	int ifindex, iflink;
6053 	void *protoinfo;
6054 
6055 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*hdr), flags);
6056 	if (!nlh)
6057 		return -EMSGSIZE;
6058 
6059 	hdr = nlmsg_data(nlh);
6060 	hdr->ifi_family = AF_INET6;
6061 	hdr->__ifi_pad = 0;
6062 	hdr->ifi_type = dev->type;
6063 	ifindex = READ_ONCE(dev->ifindex);
6064 	hdr->ifi_index = ifindex;
6065 	hdr->ifi_flags = dev_get_flags(dev);
6066 	hdr->ifi_change = 0;
6067 
6068 	iflink = dev_get_iflink(dev);
6069 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
6070 	    (dev->addr_len &&
6071 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
6072 	    nla_put_u32(skb, IFLA_MTU, READ_ONCE(dev->mtu)) ||
6073 	    (ifindex != iflink &&
6074 	     nla_put_u32(skb, IFLA_LINK, iflink)) ||
6075 	    nla_put_u8(skb, IFLA_OPERSTATE,
6076 		       netif_running(dev) ? READ_ONCE(dev->operstate) : IF_OPER_DOWN))
6077 		goto nla_put_failure;
6078 	protoinfo = nla_nest_start_noflag(skb, IFLA_PROTINFO);
6079 	if (!protoinfo)
6080 		goto nla_put_failure;
6081 
6082 	if (inet6_fill_ifla6_attrs(skb, idev, 0) < 0)
6083 		goto nla_put_failure;
6084 
6085 	nla_nest_end(skb, protoinfo);
6086 	nlmsg_end(skb, nlh);
6087 	return 0;
6088 
6089 nla_put_failure:
6090 	nlmsg_cancel(skb, nlh);
6091 	return -EMSGSIZE;
6092 }
6093 
6094 static int inet6_valid_dump_ifinfo(const struct nlmsghdr *nlh,
6095 				   struct netlink_ext_ack *extack)
6096 {
6097 	struct ifinfomsg *ifm;
6098 
6099 	if (nlh->nlmsg_len < nlmsg_msg_size(sizeof(*ifm))) {
6100 		NL_SET_ERR_MSG_MOD(extack, "Invalid header for link dump request");
6101 		return -EINVAL;
6102 	}
6103 
6104 	if (nlmsg_attrlen(nlh, sizeof(*ifm))) {
6105 		NL_SET_ERR_MSG_MOD(extack, "Invalid data after header");
6106 		return -EINVAL;
6107 	}
6108 
6109 	ifm = nlmsg_data(nlh);
6110 	if (ifm->__ifi_pad || ifm->ifi_type || ifm->ifi_flags ||
6111 	    ifm->ifi_change || ifm->ifi_index) {
6112 		NL_SET_ERR_MSG_MOD(extack, "Invalid values in header for dump request");
6113 		return -EINVAL;
6114 	}
6115 
6116 	return 0;
6117 }
6118 
6119 static int inet6_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
6120 {
6121 	struct net *net = sock_net(skb->sk);
6122 	struct {
6123 		unsigned long ifindex;
6124 	} *ctx = (void *)cb->ctx;
6125 	struct net_device *dev;
6126 	struct inet6_dev *idev;
6127 	int err;
6128 
6129 	/* only requests using strict checking can pass data to
6130 	 * influence the dump
6131 	 */
6132 	if (cb->strict_check) {
6133 		err = inet6_valid_dump_ifinfo(cb->nlh, cb->extack);
6134 
6135 		if (err < 0)
6136 			return err;
6137 	}
6138 
6139 	err = 0;
6140 	rcu_read_lock();
6141 	for_each_netdev_dump(net, dev, ctx->ifindex) {
6142 		idev = __in6_dev_get(dev);
6143 		if (!idev)
6144 			continue;
6145 		err = inet6_fill_ifinfo(skb, idev,
6146 					NETLINK_CB(cb->skb).portid,
6147 					cb->nlh->nlmsg_seq,
6148 					RTM_NEWLINK, NLM_F_MULTI);
6149 		if (err < 0)
6150 			break;
6151 	}
6152 	rcu_read_unlock();
6153 
6154 	return err;
6155 }
6156 
6157 void inet6_ifinfo_notify(int event, struct inet6_dev *idev)
6158 {
6159 	struct sk_buff *skb;
6160 	struct net *net = dev_net(idev->dev);
6161 	int err = -ENOBUFS;
6162 
6163 	skb = nlmsg_new(inet6_if_nlmsg_size(), GFP_ATOMIC);
6164 	if (!skb)
6165 		goto errout;
6166 
6167 	err = inet6_fill_ifinfo(skb, idev, 0, 0, event, 0);
6168 	if (err < 0) {
6169 		/* -EMSGSIZE implies BUG in inet6_if_nlmsg_size() */
6170 		WARN_ON(err == -EMSGSIZE);
6171 		kfree_skb(skb);
6172 		goto errout;
6173 	}
6174 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_IFINFO, NULL, GFP_ATOMIC);
6175 	return;
6176 errout:
6177 	rtnl_set_sk_err(net, RTNLGRP_IPV6_IFINFO, err);
6178 }
6179 
6180 static inline size_t inet6_prefix_nlmsg_size(void)
6181 {
6182 	return NLMSG_ALIGN(sizeof(struct prefixmsg))
6183 	       + nla_total_size(sizeof(struct in6_addr))
6184 	       + nla_total_size(sizeof(struct prefix_cacheinfo));
6185 }
6186 
6187 static int inet6_fill_prefix(struct sk_buff *skb, struct inet6_dev *idev,
6188 			     struct prefix_info *pinfo, u32 portid, u32 seq,
6189 			     int event, unsigned int flags)
6190 {
6191 	struct prefixmsg *pmsg;
6192 	struct nlmsghdr *nlh;
6193 	struct prefix_cacheinfo	ci;
6194 
6195 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*pmsg), flags);
6196 	if (!nlh)
6197 		return -EMSGSIZE;
6198 
6199 	pmsg = nlmsg_data(nlh);
6200 	pmsg->prefix_family = AF_INET6;
6201 	pmsg->prefix_pad1 = 0;
6202 	pmsg->prefix_pad2 = 0;
6203 	pmsg->prefix_ifindex = idev->dev->ifindex;
6204 	pmsg->prefix_len = pinfo->prefix_len;
6205 	pmsg->prefix_type = pinfo->type;
6206 	pmsg->prefix_pad3 = 0;
6207 	pmsg->prefix_flags = pinfo->flags;
6208 
6209 	if (nla_put(skb, PREFIX_ADDRESS, sizeof(pinfo->prefix), &pinfo->prefix))
6210 		goto nla_put_failure;
6211 	ci.preferred_time = ntohl(pinfo->prefered);
6212 	ci.valid_time = ntohl(pinfo->valid);
6213 	if (nla_put(skb, PREFIX_CACHEINFO, sizeof(ci), &ci))
6214 		goto nla_put_failure;
6215 	nlmsg_end(skb, nlh);
6216 	return 0;
6217 
6218 nla_put_failure:
6219 	nlmsg_cancel(skb, nlh);
6220 	return -EMSGSIZE;
6221 }
6222 
6223 static void inet6_prefix_notify(int event, struct inet6_dev *idev,
6224 			 struct prefix_info *pinfo)
6225 {
6226 	struct sk_buff *skb;
6227 	struct net *net = dev_net(idev->dev);
6228 	int err = -ENOBUFS;
6229 
6230 	skb = nlmsg_new(inet6_prefix_nlmsg_size(), GFP_ATOMIC);
6231 	if (!skb)
6232 		goto errout;
6233 
6234 	err = inet6_fill_prefix(skb, idev, pinfo, 0, 0, event, 0);
6235 	if (err < 0) {
6236 		/* -EMSGSIZE implies BUG in inet6_prefix_nlmsg_size() */
6237 		WARN_ON(err == -EMSGSIZE);
6238 		kfree_skb(skb);
6239 		goto errout;
6240 	}
6241 	rtnl_notify(skb, net, 0, RTNLGRP_IPV6_PREFIX, NULL, GFP_ATOMIC);
6242 	return;
6243 errout:
6244 	rtnl_set_sk_err(net, RTNLGRP_IPV6_PREFIX, err);
6245 }
6246 
6247 static void __ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6248 {
6249 	struct net *net = dev_net(ifp->idev->dev);
6250 
6251 	if (event)
6252 		ASSERT_RTNL();
6253 
6254 	inet6_ifa_notify(event ? : RTM_NEWADDR, ifp);
6255 
6256 	switch (event) {
6257 	case RTM_NEWADDR:
6258 		/*
6259 		 * If the address was optimistic we inserted the route at the
6260 		 * start of our DAD process, so we don't need to do it again.
6261 		 * If the device was taken down in the middle of the DAD
6262 		 * cycle there is a race where we could get here without a
6263 		 * host route, so nothing to insert. That will be fixed when
6264 		 * the device is brought up.
6265 		 */
6266 		if (ifp->rt && !rcu_access_pointer(ifp->rt->fib6_node)) {
6267 			ip6_ins_rt(net, ifp->rt);
6268 		} else if (!ifp->rt && (ifp->idev->dev->flags & IFF_UP)) {
6269 			pr_warn("BUG: Address %pI6c on device %s is missing its host route.\n",
6270 				&ifp->addr, ifp->idev->dev->name);
6271 		}
6272 
6273 		if (ifp->idev->cnf.forwarding)
6274 			addrconf_join_anycast(ifp);
6275 		if (!ipv6_addr_any(&ifp->peer_addr))
6276 			addrconf_prefix_route(&ifp->peer_addr, 128,
6277 					      ifp->rt_priority, ifp->idev->dev,
6278 					      0, 0, GFP_ATOMIC);
6279 		break;
6280 	case RTM_DELADDR:
6281 		if (ifp->idev->cnf.forwarding)
6282 			addrconf_leave_anycast(ifp);
6283 		addrconf_leave_solict(ifp->idev, &ifp->addr);
6284 		if (!ipv6_addr_any(&ifp->peer_addr)) {
6285 			struct fib6_info *rt;
6286 
6287 			rt = addrconf_get_prefix_route(&ifp->peer_addr, 128,
6288 						       ifp->idev->dev, 0, 0,
6289 						       false);
6290 			if (rt)
6291 				ip6_del_rt(net, rt, false);
6292 		}
6293 		if (ifp->rt) {
6294 			ip6_del_rt(net, ifp->rt, false);
6295 			ifp->rt = NULL;
6296 		}
6297 		rt_genid_bump_ipv6(net);
6298 		break;
6299 	}
6300 	atomic_inc(&net->ipv6.dev_addr_genid);
6301 }
6302 
6303 static void ipv6_ifa_notify(int event, struct inet6_ifaddr *ifp)
6304 {
6305 	if (likely(ifp->idev->dead == 0))
6306 		__ipv6_ifa_notify(event, ifp);
6307 }
6308 
6309 #ifdef CONFIG_SYSCTL
6310 
6311 static int addrconf_sysctl_forward(const struct ctl_table *ctl, int write,
6312 		void *buffer, size_t *lenp, loff_t *ppos)
6313 {
6314 	int *valp = ctl->data;
6315 	int val = *valp;
6316 	loff_t pos = *ppos;
6317 	struct ctl_table lctl;
6318 	int ret;
6319 
6320 	/*
6321 	 * ctl->data points to idev->cnf.forwarding, we should
6322 	 * not modify it until we get the rtnl lock.
6323 	 */
6324 	lctl = *ctl;
6325 	lctl.data = &val;
6326 
6327 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6328 
6329 	if (write)
6330 		ret = addrconf_fixup_forwarding(ctl, valp, val);
6331 	if (ret)
6332 		*ppos = pos;
6333 	return ret;
6334 }
6335 
6336 static int addrconf_sysctl_mtu(const struct ctl_table *ctl, int write,
6337 		void *buffer, size_t *lenp, loff_t *ppos)
6338 {
6339 	struct inet6_dev *idev = ctl->extra1;
6340 	int min_mtu = IPV6_MIN_MTU;
6341 	struct ctl_table lctl;
6342 
6343 	lctl = *ctl;
6344 	lctl.extra1 = &min_mtu;
6345 	lctl.extra2 = idev ? &idev->dev->mtu : NULL;
6346 
6347 	return proc_dointvec_minmax(&lctl, write, buffer, lenp, ppos);
6348 }
6349 
6350 static void dev_disable_change(struct inet6_dev *idev)
6351 {
6352 	struct netdev_notifier_info info;
6353 
6354 	if (!idev || !idev->dev)
6355 		return;
6356 
6357 	netdev_notifier_info_init(&info, idev->dev);
6358 	if (idev->cnf.disable_ipv6)
6359 		addrconf_notify(NULL, NETDEV_DOWN, &info);
6360 	else
6361 		addrconf_notify(NULL, NETDEV_UP, &info);
6362 }
6363 
6364 static void addrconf_disable_change(struct net *net, __s32 newf)
6365 {
6366 	struct net_device *dev;
6367 	struct inet6_dev *idev;
6368 
6369 	for_each_netdev(net, dev) {
6370 		idev = __in6_dev_get(dev);
6371 		if (idev) {
6372 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
6373 
6374 			WRITE_ONCE(idev->cnf.disable_ipv6, newf);
6375 			if (changed)
6376 				dev_disable_change(idev);
6377 		}
6378 	}
6379 }
6380 
6381 static int addrconf_disable_ipv6(const struct ctl_table *table, int *p, int newf)
6382 {
6383 	struct net *net = (struct net *)table->extra2;
6384 	int old;
6385 
6386 	if (p == &net->ipv6.devconf_dflt->disable_ipv6) {
6387 		WRITE_ONCE(*p, newf);
6388 		return 0;
6389 	}
6390 
6391 	if (!rtnl_trylock())
6392 		return restart_syscall();
6393 
6394 	old = *p;
6395 	WRITE_ONCE(*p, newf);
6396 
6397 	if (p == &net->ipv6.devconf_all->disable_ipv6) {
6398 		WRITE_ONCE(net->ipv6.devconf_dflt->disable_ipv6, newf);
6399 		addrconf_disable_change(net, newf);
6400 	} else if ((!newf) ^ (!old))
6401 		dev_disable_change((struct inet6_dev *)table->extra1);
6402 
6403 	rtnl_unlock();
6404 	return 0;
6405 }
6406 
6407 static int addrconf_sysctl_disable(const struct ctl_table *ctl, int write,
6408 		void *buffer, size_t *lenp, loff_t *ppos)
6409 {
6410 	int *valp = ctl->data;
6411 	int val = *valp;
6412 	loff_t pos = *ppos;
6413 	struct ctl_table lctl;
6414 	int ret;
6415 
6416 	/*
6417 	 * ctl->data points to idev->cnf.disable_ipv6, we should
6418 	 * not modify it until we get the rtnl lock.
6419 	 */
6420 	lctl = *ctl;
6421 	lctl.data = &val;
6422 
6423 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6424 
6425 	if (write)
6426 		ret = addrconf_disable_ipv6(ctl, valp, val);
6427 	if (ret)
6428 		*ppos = pos;
6429 	return ret;
6430 }
6431 
6432 static int addrconf_sysctl_proxy_ndp(const struct ctl_table *ctl, int write,
6433 		void *buffer, size_t *lenp, loff_t *ppos)
6434 {
6435 	int *valp = ctl->data;
6436 	int ret;
6437 	int old, new;
6438 
6439 	old = *valp;
6440 	ret = proc_dointvec(ctl, write, buffer, lenp, ppos);
6441 	new = *valp;
6442 
6443 	if (write && old != new) {
6444 		struct net *net = ctl->extra2;
6445 
6446 		if (!rtnl_trylock())
6447 			return restart_syscall();
6448 
6449 		if (valp == &net->ipv6.devconf_dflt->proxy_ndp)
6450 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6451 						     NETCONFA_PROXY_NEIGH,
6452 						     NETCONFA_IFINDEX_DEFAULT,
6453 						     net->ipv6.devconf_dflt);
6454 		else if (valp == &net->ipv6.devconf_all->proxy_ndp)
6455 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6456 						     NETCONFA_PROXY_NEIGH,
6457 						     NETCONFA_IFINDEX_ALL,
6458 						     net->ipv6.devconf_all);
6459 		else {
6460 			struct inet6_dev *idev = ctl->extra1;
6461 
6462 			inet6_netconf_notify_devconf(net, RTM_NEWNETCONF,
6463 						     NETCONFA_PROXY_NEIGH,
6464 						     idev->dev->ifindex,
6465 						     &idev->cnf);
6466 		}
6467 		rtnl_unlock();
6468 	}
6469 
6470 	return ret;
6471 }
6472 
6473 static int addrconf_sysctl_addr_gen_mode(const struct ctl_table *ctl, int write,
6474 					 void *buffer, size_t *lenp,
6475 					 loff_t *ppos)
6476 {
6477 	int ret = 0;
6478 	u32 new_val;
6479 	struct inet6_dev *idev = (struct inet6_dev *)ctl->extra1;
6480 	struct net *net = (struct net *)ctl->extra2;
6481 	struct ctl_table tmp = {
6482 		.data = &new_val,
6483 		.maxlen = sizeof(new_val),
6484 		.mode = ctl->mode,
6485 	};
6486 
6487 	if (!rtnl_trylock())
6488 		return restart_syscall();
6489 
6490 	new_val = *((u32 *)ctl->data);
6491 
6492 	ret = proc_douintvec(&tmp, write, buffer, lenp, ppos);
6493 	if (ret != 0)
6494 		goto out;
6495 
6496 	if (write) {
6497 		if (check_addr_gen_mode(new_val) < 0) {
6498 			ret = -EINVAL;
6499 			goto out;
6500 		}
6501 
6502 		if (idev) {
6503 			if (check_stable_privacy(idev, net, new_val) < 0) {
6504 				ret = -EINVAL;
6505 				goto out;
6506 			}
6507 
6508 			if (idev->cnf.addr_gen_mode != new_val) {
6509 				WRITE_ONCE(idev->cnf.addr_gen_mode, new_val);
6510 				addrconf_init_auto_addrs(idev->dev);
6511 			}
6512 		} else if (&net->ipv6.devconf_all->addr_gen_mode == ctl->data) {
6513 			struct net_device *dev;
6514 
6515 			WRITE_ONCE(net->ipv6.devconf_dflt->addr_gen_mode, new_val);
6516 			for_each_netdev(net, dev) {
6517 				idev = __in6_dev_get(dev);
6518 				if (idev &&
6519 				    idev->cnf.addr_gen_mode != new_val) {
6520 					WRITE_ONCE(idev->cnf.addr_gen_mode,
6521 						  new_val);
6522 					addrconf_init_auto_addrs(idev->dev);
6523 				}
6524 			}
6525 		}
6526 
6527 		WRITE_ONCE(*((u32 *)ctl->data), new_val);
6528 	}
6529 
6530 out:
6531 	rtnl_unlock();
6532 
6533 	return ret;
6534 }
6535 
6536 static int addrconf_sysctl_stable_secret(const struct ctl_table *ctl, int write,
6537 					 void *buffer, size_t *lenp,
6538 					 loff_t *ppos)
6539 {
6540 	int err;
6541 	struct in6_addr addr;
6542 	char str[IPV6_MAX_STRLEN];
6543 	struct ctl_table lctl = *ctl;
6544 	struct net *net = ctl->extra2;
6545 	struct ipv6_stable_secret *secret = ctl->data;
6546 
6547 	if (&net->ipv6.devconf_all->stable_secret == ctl->data)
6548 		return -EIO;
6549 
6550 	lctl.maxlen = IPV6_MAX_STRLEN;
6551 	lctl.data = str;
6552 
6553 	if (!rtnl_trylock())
6554 		return restart_syscall();
6555 
6556 	if (!write && !secret->initialized) {
6557 		err = -EIO;
6558 		goto out;
6559 	}
6560 
6561 	err = snprintf(str, sizeof(str), "%pI6", &secret->secret);
6562 	if (err >= sizeof(str)) {
6563 		err = -EIO;
6564 		goto out;
6565 	}
6566 
6567 	err = proc_dostring(&lctl, write, buffer, lenp, ppos);
6568 	if (err || !write)
6569 		goto out;
6570 
6571 	if (in6_pton(str, -1, addr.in6_u.u6_addr8, -1, NULL) != 1) {
6572 		err = -EIO;
6573 		goto out;
6574 	}
6575 
6576 	secret->initialized = true;
6577 	secret->secret = addr;
6578 
6579 	if (&net->ipv6.devconf_dflt->stable_secret == ctl->data) {
6580 		struct net_device *dev;
6581 
6582 		for_each_netdev(net, dev) {
6583 			struct inet6_dev *idev = __in6_dev_get(dev);
6584 
6585 			if (idev) {
6586 				WRITE_ONCE(idev->cnf.addr_gen_mode,
6587 					   IN6_ADDR_GEN_MODE_STABLE_PRIVACY);
6588 			}
6589 		}
6590 	} else {
6591 		struct inet6_dev *idev = ctl->extra1;
6592 
6593 		WRITE_ONCE(idev->cnf.addr_gen_mode,
6594 			   IN6_ADDR_GEN_MODE_STABLE_PRIVACY);
6595 	}
6596 
6597 out:
6598 	rtnl_unlock();
6599 
6600 	return err;
6601 }
6602 
6603 static
6604 int addrconf_sysctl_ignore_routes_with_linkdown(const struct ctl_table *ctl,
6605 						int write, void *buffer,
6606 						size_t *lenp,
6607 						loff_t *ppos)
6608 {
6609 	int *valp = ctl->data;
6610 	int val = *valp;
6611 	loff_t pos = *ppos;
6612 	struct ctl_table lctl;
6613 	int ret;
6614 
6615 	/* ctl->data points to idev->cnf.ignore_routes_when_linkdown
6616 	 * we should not modify it until we get the rtnl lock.
6617 	 */
6618 	lctl = *ctl;
6619 	lctl.data = &val;
6620 
6621 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6622 
6623 	if (write)
6624 		ret = addrconf_fixup_linkdown(ctl, valp, val);
6625 	if (ret)
6626 		*ppos = pos;
6627 	return ret;
6628 }
6629 
6630 static
6631 void addrconf_set_nopolicy(struct rt6_info *rt, int action)
6632 {
6633 	if (rt) {
6634 		if (action)
6635 			rt->dst.flags |= DST_NOPOLICY;
6636 		else
6637 			rt->dst.flags &= ~DST_NOPOLICY;
6638 	}
6639 }
6640 
6641 static
6642 void addrconf_disable_policy_idev(struct inet6_dev *idev, int val)
6643 {
6644 	struct inet6_ifaddr *ifa;
6645 
6646 	read_lock_bh(&idev->lock);
6647 	list_for_each_entry(ifa, &idev->addr_list, if_list) {
6648 		spin_lock(&ifa->lock);
6649 		if (ifa->rt) {
6650 			/* host routes only use builtin fib6_nh */
6651 			struct fib6_nh *nh = ifa->rt->fib6_nh;
6652 			int cpu;
6653 
6654 			rcu_read_lock();
6655 			ifa->rt->dst_nopolicy = val ? true : false;
6656 			if (nh->rt6i_pcpu) {
6657 				for_each_possible_cpu(cpu) {
6658 					struct rt6_info **rtp;
6659 
6660 					rtp = per_cpu_ptr(nh->rt6i_pcpu, cpu);
6661 					addrconf_set_nopolicy(*rtp, val);
6662 				}
6663 			}
6664 			rcu_read_unlock();
6665 		}
6666 		spin_unlock(&ifa->lock);
6667 	}
6668 	read_unlock_bh(&idev->lock);
6669 }
6670 
6671 static
6672 int addrconf_disable_policy(const struct ctl_table *ctl, int *valp, int val)
6673 {
6674 	struct net *net = (struct net *)ctl->extra2;
6675 	struct inet6_dev *idev;
6676 
6677 	if (valp == &net->ipv6.devconf_dflt->disable_policy) {
6678 		WRITE_ONCE(*valp, val);
6679 		return 0;
6680 	}
6681 
6682 	if (!rtnl_trylock())
6683 		return restart_syscall();
6684 
6685 	WRITE_ONCE(*valp, val);
6686 
6687 	if (valp == &net->ipv6.devconf_all->disable_policy)  {
6688 		struct net_device *dev;
6689 
6690 		for_each_netdev(net, dev) {
6691 			idev = __in6_dev_get(dev);
6692 			if (idev)
6693 				addrconf_disable_policy_idev(idev, val);
6694 		}
6695 	} else {
6696 		idev = (struct inet6_dev *)ctl->extra1;
6697 		addrconf_disable_policy_idev(idev, val);
6698 	}
6699 
6700 	rtnl_unlock();
6701 	return 0;
6702 }
6703 
6704 static int addrconf_sysctl_disable_policy(const struct ctl_table *ctl, int write,
6705 				   void *buffer, size_t *lenp, loff_t *ppos)
6706 {
6707 	int *valp = ctl->data;
6708 	int val = *valp;
6709 	loff_t pos = *ppos;
6710 	struct ctl_table lctl;
6711 	int ret;
6712 
6713 	lctl = *ctl;
6714 	lctl.data = &val;
6715 	ret = proc_dointvec(&lctl, write, buffer, lenp, ppos);
6716 
6717 	if (write && (*valp != val))
6718 		ret = addrconf_disable_policy(ctl, valp, val);
6719 
6720 	if (ret)
6721 		*ppos = pos;
6722 
6723 	return ret;
6724 }
6725 
6726 static int minus_one = -1;
6727 static const int two_five_five = 255;
6728 static u32 ioam6_if_id_max = U16_MAX;
6729 
6730 static const struct ctl_table addrconf_sysctl[] = {
6731 	{
6732 		.procname	= "forwarding",
6733 		.data		= &ipv6_devconf.forwarding,
6734 		.maxlen		= sizeof(int),
6735 		.mode		= 0644,
6736 		.proc_handler	= addrconf_sysctl_forward,
6737 	},
6738 	{
6739 		.procname	= "hop_limit",
6740 		.data		= &ipv6_devconf.hop_limit,
6741 		.maxlen		= sizeof(int),
6742 		.mode		= 0644,
6743 		.proc_handler	= proc_dointvec_minmax,
6744 		.extra1		= (void *)SYSCTL_ONE,
6745 		.extra2		= (void *)&two_five_five,
6746 	},
6747 	{
6748 		.procname	= "mtu",
6749 		.data		= &ipv6_devconf.mtu6,
6750 		.maxlen		= sizeof(int),
6751 		.mode		= 0644,
6752 		.proc_handler	= addrconf_sysctl_mtu,
6753 	},
6754 	{
6755 		.procname	= "accept_ra",
6756 		.data		= &ipv6_devconf.accept_ra,
6757 		.maxlen		= sizeof(int),
6758 		.mode		= 0644,
6759 		.proc_handler	= proc_dointvec,
6760 	},
6761 	{
6762 		.procname	= "accept_redirects",
6763 		.data		= &ipv6_devconf.accept_redirects,
6764 		.maxlen		= sizeof(int),
6765 		.mode		= 0644,
6766 		.proc_handler	= proc_dointvec,
6767 	},
6768 	{
6769 		.procname	= "autoconf",
6770 		.data		= &ipv6_devconf.autoconf,
6771 		.maxlen		= sizeof(int),
6772 		.mode		= 0644,
6773 		.proc_handler	= proc_dointvec,
6774 	},
6775 	{
6776 		.procname	= "dad_transmits",
6777 		.data		= &ipv6_devconf.dad_transmits,
6778 		.maxlen		= sizeof(int),
6779 		.mode		= 0644,
6780 		.proc_handler	= proc_dointvec,
6781 	},
6782 	{
6783 		.procname	= "router_solicitations",
6784 		.data		= &ipv6_devconf.rtr_solicits,
6785 		.maxlen		= sizeof(int),
6786 		.mode		= 0644,
6787 		.proc_handler	= proc_dointvec_minmax,
6788 		.extra1		= &minus_one,
6789 	},
6790 	{
6791 		.procname	= "router_solicitation_interval",
6792 		.data		= &ipv6_devconf.rtr_solicit_interval,
6793 		.maxlen		= sizeof(int),
6794 		.mode		= 0644,
6795 		.proc_handler	= proc_dointvec_jiffies,
6796 	},
6797 	{
6798 		.procname	= "router_solicitation_max_interval",
6799 		.data		= &ipv6_devconf.rtr_solicit_max_interval,
6800 		.maxlen		= sizeof(int),
6801 		.mode		= 0644,
6802 		.proc_handler	= proc_dointvec_jiffies,
6803 	},
6804 	{
6805 		.procname	= "router_solicitation_delay",
6806 		.data		= &ipv6_devconf.rtr_solicit_delay,
6807 		.maxlen		= sizeof(int),
6808 		.mode		= 0644,
6809 		.proc_handler	= proc_dointvec_jiffies,
6810 	},
6811 	{
6812 		.procname	= "force_mld_version",
6813 		.data		= &ipv6_devconf.force_mld_version,
6814 		.maxlen		= sizeof(int),
6815 		.mode		= 0644,
6816 		.proc_handler	= proc_dointvec,
6817 	},
6818 	{
6819 		.procname	= "mldv1_unsolicited_report_interval",
6820 		.data		=
6821 			&ipv6_devconf.mldv1_unsolicited_report_interval,
6822 		.maxlen		= sizeof(int),
6823 		.mode		= 0644,
6824 		.proc_handler	= proc_dointvec_ms_jiffies,
6825 	},
6826 	{
6827 		.procname	= "mldv2_unsolicited_report_interval",
6828 		.data		=
6829 			&ipv6_devconf.mldv2_unsolicited_report_interval,
6830 		.maxlen		= sizeof(int),
6831 		.mode		= 0644,
6832 		.proc_handler	= proc_dointvec_ms_jiffies,
6833 	},
6834 	{
6835 		.procname	= "use_tempaddr",
6836 		.data		= &ipv6_devconf.use_tempaddr,
6837 		.maxlen		= sizeof(int),
6838 		.mode		= 0644,
6839 		.proc_handler	= proc_dointvec,
6840 	},
6841 	{
6842 		.procname	= "temp_valid_lft",
6843 		.data		= &ipv6_devconf.temp_valid_lft,
6844 		.maxlen		= sizeof(int),
6845 		.mode		= 0644,
6846 		.proc_handler	= proc_dointvec,
6847 	},
6848 	{
6849 		.procname	= "temp_prefered_lft",
6850 		.data		= &ipv6_devconf.temp_prefered_lft,
6851 		.maxlen		= sizeof(int),
6852 		.mode		= 0644,
6853 		.proc_handler	= proc_dointvec,
6854 	},
6855 	{
6856 		.procname       = "regen_min_advance",
6857 		.data           = &ipv6_devconf.regen_min_advance,
6858 		.maxlen         = sizeof(int),
6859 		.mode           = 0644,
6860 		.proc_handler   = proc_dointvec,
6861 	},
6862 	{
6863 		.procname	= "regen_max_retry",
6864 		.data		= &ipv6_devconf.regen_max_retry,
6865 		.maxlen		= sizeof(int),
6866 		.mode		= 0644,
6867 		.proc_handler	= proc_dointvec,
6868 	},
6869 	{
6870 		.procname	= "max_desync_factor",
6871 		.data		= &ipv6_devconf.max_desync_factor,
6872 		.maxlen		= sizeof(int),
6873 		.mode		= 0644,
6874 		.proc_handler	= proc_dointvec,
6875 	},
6876 	{
6877 		.procname	= "max_addresses",
6878 		.data		= &ipv6_devconf.max_addresses,
6879 		.maxlen		= sizeof(int),
6880 		.mode		= 0644,
6881 		.proc_handler	= proc_dointvec,
6882 	},
6883 	{
6884 		.procname	= "accept_ra_defrtr",
6885 		.data		= &ipv6_devconf.accept_ra_defrtr,
6886 		.maxlen		= sizeof(int),
6887 		.mode		= 0644,
6888 		.proc_handler	= proc_dointvec,
6889 	},
6890 	{
6891 		.procname	= "ra_defrtr_metric",
6892 		.data		= &ipv6_devconf.ra_defrtr_metric,
6893 		.maxlen		= sizeof(u32),
6894 		.mode		= 0644,
6895 		.proc_handler	= proc_douintvec_minmax,
6896 		.extra1		= (void *)SYSCTL_ONE,
6897 	},
6898 	{
6899 		.procname	= "accept_ra_min_hop_limit",
6900 		.data		= &ipv6_devconf.accept_ra_min_hop_limit,
6901 		.maxlen		= sizeof(int),
6902 		.mode		= 0644,
6903 		.proc_handler	= proc_dointvec,
6904 	},
6905 	{
6906 		.procname	= "accept_ra_min_lft",
6907 		.data		= &ipv6_devconf.accept_ra_min_lft,
6908 		.maxlen		= sizeof(int),
6909 		.mode		= 0644,
6910 		.proc_handler	= proc_dointvec,
6911 	},
6912 	{
6913 		.procname	= "accept_ra_pinfo",
6914 		.data		= &ipv6_devconf.accept_ra_pinfo,
6915 		.maxlen		= sizeof(int),
6916 		.mode		= 0644,
6917 		.proc_handler	= proc_dointvec,
6918 	},
6919 	{
6920 		.procname	= "ra_honor_pio_life",
6921 		.data		= &ipv6_devconf.ra_honor_pio_life,
6922 		.maxlen		= sizeof(u8),
6923 		.mode		= 0644,
6924 		.proc_handler	= proc_dou8vec_minmax,
6925 		.extra1		= SYSCTL_ZERO,
6926 		.extra2		= SYSCTL_ONE,
6927 	},
6928 	{
6929 		.procname	= "ra_honor_pio_pflag",
6930 		.data		= &ipv6_devconf.ra_honor_pio_pflag,
6931 		.maxlen		= sizeof(u8),
6932 		.mode		= 0644,
6933 		.proc_handler	= proc_dou8vec_minmax,
6934 		.extra1		= SYSCTL_ZERO,
6935 		.extra2		= SYSCTL_ONE,
6936 	},
6937 #ifdef CONFIG_IPV6_ROUTER_PREF
6938 	{
6939 		.procname	= "accept_ra_rtr_pref",
6940 		.data		= &ipv6_devconf.accept_ra_rtr_pref,
6941 		.maxlen		= sizeof(int),
6942 		.mode		= 0644,
6943 		.proc_handler	= proc_dointvec,
6944 	},
6945 	{
6946 		.procname	= "router_probe_interval",
6947 		.data		= &ipv6_devconf.rtr_probe_interval,
6948 		.maxlen		= sizeof(int),
6949 		.mode		= 0644,
6950 		.proc_handler	= proc_dointvec_jiffies,
6951 	},
6952 #ifdef CONFIG_IPV6_ROUTE_INFO
6953 	{
6954 		.procname	= "accept_ra_rt_info_min_plen",
6955 		.data		= &ipv6_devconf.accept_ra_rt_info_min_plen,
6956 		.maxlen		= sizeof(int),
6957 		.mode		= 0644,
6958 		.proc_handler	= proc_dointvec,
6959 	},
6960 	{
6961 		.procname	= "accept_ra_rt_info_max_plen",
6962 		.data		= &ipv6_devconf.accept_ra_rt_info_max_plen,
6963 		.maxlen		= sizeof(int),
6964 		.mode		= 0644,
6965 		.proc_handler	= proc_dointvec,
6966 	},
6967 #endif
6968 #endif
6969 	{
6970 		.procname	= "proxy_ndp",
6971 		.data		= &ipv6_devconf.proxy_ndp,
6972 		.maxlen		= sizeof(int),
6973 		.mode		= 0644,
6974 		.proc_handler	= addrconf_sysctl_proxy_ndp,
6975 	},
6976 	{
6977 		.procname	= "accept_source_route",
6978 		.data		= &ipv6_devconf.accept_source_route,
6979 		.maxlen		= sizeof(int),
6980 		.mode		= 0644,
6981 		.proc_handler	= proc_dointvec,
6982 	},
6983 #ifdef CONFIG_IPV6_OPTIMISTIC_DAD
6984 	{
6985 		.procname	= "optimistic_dad",
6986 		.data		= &ipv6_devconf.optimistic_dad,
6987 		.maxlen		= sizeof(int),
6988 		.mode		= 0644,
6989 		.proc_handler   = proc_dointvec,
6990 	},
6991 	{
6992 		.procname	= "use_optimistic",
6993 		.data		= &ipv6_devconf.use_optimistic,
6994 		.maxlen		= sizeof(int),
6995 		.mode		= 0644,
6996 		.proc_handler	= proc_dointvec,
6997 	},
6998 #endif
6999 #ifdef CONFIG_IPV6_MROUTE
7000 	{
7001 		.procname	= "mc_forwarding",
7002 		.data		= &ipv6_devconf.mc_forwarding,
7003 		.maxlen		= sizeof(int),
7004 		.mode		= 0444,
7005 		.proc_handler	= proc_dointvec,
7006 	},
7007 #endif
7008 	{
7009 		.procname	= "disable_ipv6",
7010 		.data		= &ipv6_devconf.disable_ipv6,
7011 		.maxlen		= sizeof(int),
7012 		.mode		= 0644,
7013 		.proc_handler	= addrconf_sysctl_disable,
7014 	},
7015 	{
7016 		.procname	= "accept_dad",
7017 		.data		= &ipv6_devconf.accept_dad,
7018 		.maxlen		= sizeof(int),
7019 		.mode		= 0644,
7020 		.proc_handler	= proc_dointvec,
7021 	},
7022 	{
7023 		.procname	= "force_tllao",
7024 		.data		= &ipv6_devconf.force_tllao,
7025 		.maxlen		= sizeof(int),
7026 		.mode		= 0644,
7027 		.proc_handler	= proc_dointvec
7028 	},
7029 	{
7030 		.procname	= "ndisc_notify",
7031 		.data		= &ipv6_devconf.ndisc_notify,
7032 		.maxlen		= sizeof(int),
7033 		.mode		= 0644,
7034 		.proc_handler	= proc_dointvec
7035 	},
7036 	{
7037 		.procname	= "suppress_frag_ndisc",
7038 		.data		= &ipv6_devconf.suppress_frag_ndisc,
7039 		.maxlen		= sizeof(int),
7040 		.mode		= 0644,
7041 		.proc_handler	= proc_dointvec
7042 	},
7043 	{
7044 		.procname	= "accept_ra_from_local",
7045 		.data		= &ipv6_devconf.accept_ra_from_local,
7046 		.maxlen		= sizeof(int),
7047 		.mode		= 0644,
7048 		.proc_handler	= proc_dointvec,
7049 	},
7050 	{
7051 		.procname	= "accept_ra_mtu",
7052 		.data		= &ipv6_devconf.accept_ra_mtu,
7053 		.maxlen		= sizeof(int),
7054 		.mode		= 0644,
7055 		.proc_handler	= proc_dointvec,
7056 	},
7057 	{
7058 		.procname	= "stable_secret",
7059 		.data		= &ipv6_devconf.stable_secret,
7060 		.maxlen		= IPV6_MAX_STRLEN,
7061 		.mode		= 0600,
7062 		.proc_handler	= addrconf_sysctl_stable_secret,
7063 	},
7064 	{
7065 		.procname	= "use_oif_addrs_only",
7066 		.data		= &ipv6_devconf.use_oif_addrs_only,
7067 		.maxlen		= sizeof(int),
7068 		.mode		= 0644,
7069 		.proc_handler	= proc_dointvec,
7070 	},
7071 	{
7072 		.procname	= "ignore_routes_with_linkdown",
7073 		.data		= &ipv6_devconf.ignore_routes_with_linkdown,
7074 		.maxlen		= sizeof(int),
7075 		.mode		= 0644,
7076 		.proc_handler	= addrconf_sysctl_ignore_routes_with_linkdown,
7077 	},
7078 	{
7079 		.procname	= "drop_unicast_in_l2_multicast",
7080 		.data		= &ipv6_devconf.drop_unicast_in_l2_multicast,
7081 		.maxlen		= sizeof(int),
7082 		.mode		= 0644,
7083 		.proc_handler	= proc_dointvec,
7084 	},
7085 	{
7086 		.procname	= "drop_unsolicited_na",
7087 		.data		= &ipv6_devconf.drop_unsolicited_na,
7088 		.maxlen		= sizeof(int),
7089 		.mode		= 0644,
7090 		.proc_handler	= proc_dointvec,
7091 	},
7092 	{
7093 		.procname	= "keep_addr_on_down",
7094 		.data		= &ipv6_devconf.keep_addr_on_down,
7095 		.maxlen		= sizeof(int),
7096 		.mode		= 0644,
7097 		.proc_handler	= proc_dointvec,
7098 
7099 	},
7100 	{
7101 		.procname	= "seg6_enabled",
7102 		.data		= &ipv6_devconf.seg6_enabled,
7103 		.maxlen		= sizeof(int),
7104 		.mode		= 0644,
7105 		.proc_handler	= proc_dointvec,
7106 	},
7107 #ifdef CONFIG_IPV6_SEG6_HMAC
7108 	{
7109 		.procname	= "seg6_require_hmac",
7110 		.data		= &ipv6_devconf.seg6_require_hmac,
7111 		.maxlen		= sizeof(int),
7112 		.mode		= 0644,
7113 		.proc_handler	= proc_dointvec,
7114 	},
7115 #endif
7116 	{
7117 		.procname       = "enhanced_dad",
7118 		.data           = &ipv6_devconf.enhanced_dad,
7119 		.maxlen         = sizeof(int),
7120 		.mode           = 0644,
7121 		.proc_handler   = proc_dointvec,
7122 	},
7123 	{
7124 		.procname	= "addr_gen_mode",
7125 		.data		= &ipv6_devconf.addr_gen_mode,
7126 		.maxlen		= sizeof(int),
7127 		.mode		= 0644,
7128 		.proc_handler	= addrconf_sysctl_addr_gen_mode,
7129 	},
7130 	{
7131 		.procname       = "disable_policy",
7132 		.data           = &ipv6_devconf.disable_policy,
7133 		.maxlen         = sizeof(int),
7134 		.mode           = 0644,
7135 		.proc_handler   = addrconf_sysctl_disable_policy,
7136 	},
7137 	{
7138 		.procname	= "ndisc_tclass",
7139 		.data		= &ipv6_devconf.ndisc_tclass,
7140 		.maxlen		= sizeof(int),
7141 		.mode		= 0644,
7142 		.proc_handler	= proc_dointvec_minmax,
7143 		.extra1		= (void *)SYSCTL_ZERO,
7144 		.extra2		= (void *)&two_five_five,
7145 	},
7146 	{
7147 		.procname	= "rpl_seg_enabled",
7148 		.data		= &ipv6_devconf.rpl_seg_enabled,
7149 		.maxlen		= sizeof(int),
7150 		.mode		= 0644,
7151 		.proc_handler	= proc_dointvec,
7152 	},
7153 	{
7154 		.procname	= "ioam6_enabled",
7155 		.data		= &ipv6_devconf.ioam6_enabled,
7156 		.maxlen		= sizeof(u8),
7157 		.mode		= 0644,
7158 		.proc_handler	= proc_dou8vec_minmax,
7159 		.extra1		= (void *)SYSCTL_ZERO,
7160 		.extra2		= (void *)SYSCTL_ONE,
7161 	},
7162 	{
7163 		.procname	= "ioam6_id",
7164 		.data		= &ipv6_devconf.ioam6_id,
7165 		.maxlen		= sizeof(u32),
7166 		.mode		= 0644,
7167 		.proc_handler	= proc_douintvec_minmax,
7168 		.extra1		= (void *)SYSCTL_ZERO,
7169 		.extra2		= (void *)&ioam6_if_id_max,
7170 	},
7171 	{
7172 		.procname	= "ioam6_id_wide",
7173 		.data		= &ipv6_devconf.ioam6_id_wide,
7174 		.maxlen		= sizeof(u32),
7175 		.mode		= 0644,
7176 		.proc_handler	= proc_douintvec,
7177 	},
7178 	{
7179 		.procname	= "ndisc_evict_nocarrier",
7180 		.data		= &ipv6_devconf.ndisc_evict_nocarrier,
7181 		.maxlen		= sizeof(u8),
7182 		.mode		= 0644,
7183 		.proc_handler	= proc_dou8vec_minmax,
7184 		.extra1		= (void *)SYSCTL_ZERO,
7185 		.extra2		= (void *)SYSCTL_ONE,
7186 	},
7187 	{
7188 		.procname	= "accept_untracked_na",
7189 		.data		= &ipv6_devconf.accept_untracked_na,
7190 		.maxlen		= sizeof(int),
7191 		.mode		= 0644,
7192 		.proc_handler	= proc_dointvec_minmax,
7193 		.extra1		= SYSCTL_ZERO,
7194 		.extra2		= SYSCTL_TWO,
7195 	},
7196 };
7197 
7198 static int __addrconf_sysctl_register(struct net *net, char *dev_name,
7199 		struct inet6_dev *idev, struct ipv6_devconf *p)
7200 {
7201 	size_t table_size = ARRAY_SIZE(addrconf_sysctl);
7202 	int i, ifindex;
7203 	struct ctl_table *table;
7204 	char path[sizeof("net/ipv6/conf/") + IFNAMSIZ];
7205 
7206 	table = kmemdup(addrconf_sysctl, sizeof(addrconf_sysctl), GFP_KERNEL_ACCOUNT);
7207 	if (!table)
7208 		goto out;
7209 
7210 	for (i = 0; i < table_size; i++) {
7211 		table[i].data += (char *)p - (char *)&ipv6_devconf;
7212 		/* If one of these is already set, then it is not safe to
7213 		 * overwrite either of them: this makes proc_dointvec_minmax
7214 		 * usable.
7215 		 */
7216 		if (!table[i].extra1 && !table[i].extra2) {
7217 			table[i].extra1 = idev; /* embedded; no ref */
7218 			table[i].extra2 = net;
7219 		}
7220 	}
7221 
7222 	snprintf(path, sizeof(path), "net/ipv6/conf/%s", dev_name);
7223 
7224 	p->sysctl_header = register_net_sysctl_sz(net, path, table,
7225 						  table_size);
7226 	if (!p->sysctl_header)
7227 		goto free;
7228 
7229 	if (!strcmp(dev_name, "all"))
7230 		ifindex = NETCONFA_IFINDEX_ALL;
7231 	else if (!strcmp(dev_name, "default"))
7232 		ifindex = NETCONFA_IFINDEX_DEFAULT;
7233 	else
7234 		ifindex = idev->dev->ifindex;
7235 	inet6_netconf_notify_devconf(net, RTM_NEWNETCONF, NETCONFA_ALL,
7236 				     ifindex, p);
7237 	return 0;
7238 
7239 free:
7240 	kfree(table);
7241 out:
7242 	return -ENOBUFS;
7243 }
7244 
7245 static void __addrconf_sysctl_unregister(struct net *net,
7246 					 struct ipv6_devconf *p, int ifindex)
7247 {
7248 	const struct ctl_table *table;
7249 
7250 	if (!p->sysctl_header)
7251 		return;
7252 
7253 	table = p->sysctl_header->ctl_table_arg;
7254 	unregister_net_sysctl_table(p->sysctl_header);
7255 	p->sysctl_header = NULL;
7256 	kfree(table);
7257 
7258 	inet6_netconf_notify_devconf(net, RTM_DELNETCONF, 0, ifindex, NULL);
7259 }
7260 
7261 static int addrconf_sysctl_register(struct inet6_dev *idev)
7262 {
7263 	int err;
7264 
7265 	if (!sysctl_dev_name_is_allowed(idev->dev->name))
7266 		return -EINVAL;
7267 
7268 	err = neigh_sysctl_register(idev->dev, idev->nd_parms,
7269 				    &ndisc_ifinfo_sysctl_change);
7270 	if (err)
7271 		return err;
7272 	err = __addrconf_sysctl_register(dev_net(idev->dev), idev->dev->name,
7273 					 idev, &idev->cnf);
7274 	if (err)
7275 		neigh_sysctl_unregister(idev->nd_parms);
7276 
7277 	return err;
7278 }
7279 
7280 static void addrconf_sysctl_unregister(struct inet6_dev *idev)
7281 {
7282 	__addrconf_sysctl_unregister(dev_net(idev->dev), &idev->cnf,
7283 				     idev->dev->ifindex);
7284 	neigh_sysctl_unregister(idev->nd_parms);
7285 }
7286 
7287 
7288 #endif
7289 
7290 static int __net_init addrconf_init_net(struct net *net)
7291 {
7292 	int err = -ENOMEM;
7293 	struct ipv6_devconf *all, *dflt;
7294 
7295 	spin_lock_init(&net->ipv6.addrconf_hash_lock);
7296 	INIT_DEFERRABLE_WORK(&net->ipv6.addr_chk_work, addrconf_verify_work);
7297 	net->ipv6.inet6_addr_lst = kcalloc(IN6_ADDR_HSIZE,
7298 					   sizeof(struct hlist_head),
7299 					   GFP_KERNEL);
7300 	if (!net->ipv6.inet6_addr_lst)
7301 		goto err_alloc_addr;
7302 
7303 	all = kmemdup(&ipv6_devconf, sizeof(ipv6_devconf), GFP_KERNEL);
7304 	if (!all)
7305 		goto err_alloc_all;
7306 
7307 	dflt = kmemdup(&ipv6_devconf_dflt, sizeof(ipv6_devconf_dflt), GFP_KERNEL);
7308 	if (!dflt)
7309 		goto err_alloc_dflt;
7310 
7311 	if (!net_eq(net, &init_net)) {
7312 		switch (net_inherit_devconf()) {
7313 		case 1:  /* copy from init_net */
7314 			memcpy(all, init_net.ipv6.devconf_all,
7315 			       sizeof(ipv6_devconf));
7316 			memcpy(dflt, init_net.ipv6.devconf_dflt,
7317 			       sizeof(ipv6_devconf_dflt));
7318 			break;
7319 		case 3: /* copy from the current netns */
7320 			memcpy(all, current->nsproxy->net_ns->ipv6.devconf_all,
7321 			       sizeof(ipv6_devconf));
7322 			memcpy(dflt,
7323 			       current->nsproxy->net_ns->ipv6.devconf_dflt,
7324 			       sizeof(ipv6_devconf_dflt));
7325 			break;
7326 		case 0:
7327 		case 2:
7328 			/* use compiled values */
7329 			break;
7330 		}
7331 	}
7332 
7333 	/* these will be inherited by all namespaces */
7334 	dflt->autoconf = ipv6_defaults.autoconf;
7335 	dflt->disable_ipv6 = ipv6_defaults.disable_ipv6;
7336 
7337 	dflt->stable_secret.initialized = false;
7338 	all->stable_secret.initialized = false;
7339 
7340 	net->ipv6.devconf_all = all;
7341 	net->ipv6.devconf_dflt = dflt;
7342 
7343 #ifdef CONFIG_SYSCTL
7344 	err = __addrconf_sysctl_register(net, "all", NULL, all);
7345 	if (err < 0)
7346 		goto err_reg_all;
7347 
7348 	err = __addrconf_sysctl_register(net, "default", NULL, dflt);
7349 	if (err < 0)
7350 		goto err_reg_dflt;
7351 #endif
7352 	return 0;
7353 
7354 #ifdef CONFIG_SYSCTL
7355 err_reg_dflt:
7356 	__addrconf_sysctl_unregister(net, all, NETCONFA_IFINDEX_ALL);
7357 err_reg_all:
7358 	kfree(dflt);
7359 	net->ipv6.devconf_dflt = NULL;
7360 #endif
7361 err_alloc_dflt:
7362 	kfree(all);
7363 	net->ipv6.devconf_all = NULL;
7364 err_alloc_all:
7365 	kfree(net->ipv6.inet6_addr_lst);
7366 err_alloc_addr:
7367 	return err;
7368 }
7369 
7370 static void __net_exit addrconf_exit_net(struct net *net)
7371 {
7372 	int i;
7373 
7374 #ifdef CONFIG_SYSCTL
7375 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_dflt,
7376 				     NETCONFA_IFINDEX_DEFAULT);
7377 	__addrconf_sysctl_unregister(net, net->ipv6.devconf_all,
7378 				     NETCONFA_IFINDEX_ALL);
7379 #endif
7380 	kfree(net->ipv6.devconf_dflt);
7381 	net->ipv6.devconf_dflt = NULL;
7382 	kfree(net->ipv6.devconf_all);
7383 	net->ipv6.devconf_all = NULL;
7384 
7385 	cancel_delayed_work_sync(&net->ipv6.addr_chk_work);
7386 	/*
7387 	 *	Check hash table, then free it.
7388 	 */
7389 	for (i = 0; i < IN6_ADDR_HSIZE; i++)
7390 		WARN_ON_ONCE(!hlist_empty(&net->ipv6.inet6_addr_lst[i]));
7391 
7392 	kfree(net->ipv6.inet6_addr_lst);
7393 	net->ipv6.inet6_addr_lst = NULL;
7394 }
7395 
7396 static struct pernet_operations addrconf_ops = {
7397 	.init = addrconf_init_net,
7398 	.exit = addrconf_exit_net,
7399 };
7400 
7401 static struct rtnl_af_ops inet6_ops __read_mostly = {
7402 	.family		  = AF_INET6,
7403 	.fill_link_af	  = inet6_fill_link_af,
7404 	.get_link_af_size = inet6_get_link_af_size,
7405 	.validate_link_af = inet6_validate_link_af,
7406 	.set_link_af	  = inet6_set_link_af,
7407 };
7408 
7409 /*
7410  *	Init / cleanup code
7411  */
7412 
7413 int __init addrconf_init(void)
7414 {
7415 	struct inet6_dev *idev;
7416 	int err;
7417 
7418 	err = ipv6_addr_label_init();
7419 	if (err < 0) {
7420 		pr_crit("%s: cannot initialize default policy table: %d\n",
7421 			__func__, err);
7422 		goto out;
7423 	}
7424 
7425 	err = register_pernet_subsys(&addrconf_ops);
7426 	if (err < 0)
7427 		goto out_addrlabel;
7428 
7429 	/* All works using addrconf_wq need to lock rtnl. */
7430 	addrconf_wq = create_singlethread_workqueue("ipv6_addrconf");
7431 	if (!addrconf_wq) {
7432 		err = -ENOMEM;
7433 		goto out_nowq;
7434 	}
7435 
7436 	rtnl_lock();
7437 	idev = ipv6_add_dev(blackhole_netdev);
7438 	rtnl_unlock();
7439 	if (IS_ERR(idev)) {
7440 		err = PTR_ERR(idev);
7441 		goto errlo;
7442 	}
7443 
7444 	ip6_route_init_special_entries();
7445 
7446 	register_netdevice_notifier(&ipv6_dev_notf);
7447 
7448 	addrconf_verify(&init_net);
7449 
7450 	rtnl_af_register(&inet6_ops);
7451 
7452 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETLINK,
7453 				   NULL, inet6_dump_ifinfo, RTNL_FLAG_DUMP_UNLOCKED);
7454 	if (err < 0)
7455 		goto errout;
7456 
7457 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_NEWADDR,
7458 				   inet6_rtm_newaddr, NULL, 0);
7459 	if (err < 0)
7460 		goto errout;
7461 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_DELADDR,
7462 				   inet6_rtm_deladdr, NULL, 0);
7463 	if (err < 0)
7464 		goto errout;
7465 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETADDR,
7466 				   inet6_rtm_getaddr, inet6_dump_ifaddr,
7467 				   RTNL_FLAG_DOIT_UNLOCKED |
7468 				   RTNL_FLAG_DUMP_UNLOCKED);
7469 	if (err < 0)
7470 		goto errout;
7471 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETMULTICAST,
7472 				   NULL, inet6_dump_ifmcaddr,
7473 				   RTNL_FLAG_DUMP_UNLOCKED);
7474 	if (err < 0)
7475 		goto errout;
7476 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETANYCAST,
7477 				   NULL, inet6_dump_ifacaddr,
7478 				   RTNL_FLAG_DUMP_UNLOCKED);
7479 	if (err < 0)
7480 		goto errout;
7481 	err = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETNETCONF,
7482 				   inet6_netconf_get_devconf,
7483 				   inet6_netconf_dump_devconf,
7484 				   RTNL_FLAG_DOIT_UNLOCKED |
7485 				   RTNL_FLAG_DUMP_UNLOCKED);
7486 	if (err < 0)
7487 		goto errout;
7488 	err = ipv6_addr_label_rtnl_register();
7489 	if (err < 0)
7490 		goto errout;
7491 
7492 	return 0;
7493 errout:
7494 	rtnl_unregister_all(PF_INET6);
7495 	rtnl_af_unregister(&inet6_ops);
7496 	unregister_netdevice_notifier(&ipv6_dev_notf);
7497 errlo:
7498 	destroy_workqueue(addrconf_wq);
7499 out_nowq:
7500 	unregister_pernet_subsys(&addrconf_ops);
7501 out_addrlabel:
7502 	ipv6_addr_label_cleanup();
7503 out:
7504 	return err;
7505 }
7506 
7507 void addrconf_cleanup(void)
7508 {
7509 	struct net_device *dev;
7510 
7511 	unregister_netdevice_notifier(&ipv6_dev_notf);
7512 	unregister_pernet_subsys(&addrconf_ops);
7513 	ipv6_addr_label_cleanup();
7514 
7515 	rtnl_af_unregister(&inet6_ops);
7516 
7517 	rtnl_lock();
7518 
7519 	/* clean dev list */
7520 	for_each_netdev(&init_net, dev) {
7521 		if (__in6_dev_get(dev) == NULL)
7522 			continue;
7523 		addrconf_ifdown(dev, true);
7524 	}
7525 	addrconf_ifdown(init_net.loopback_dev, true);
7526 
7527 	rtnl_unlock();
7528 
7529 	destroy_workqueue(addrconf_wq);
7530 }
7531