xref: /linux/net/bridge/br_fdb.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *	Forwarding database
4  *	Linux ethernet bridge
5  *
6  *	Authors:
7  *	Lennert Buytenhek		<buytenh@gnu.org>
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/init.h>
12 #include <linux/rculist.h>
13 #include <linux/spinlock.h>
14 #include <linux/times.h>
15 #include <linux/netdevice.h>
16 #include <linux/etherdevice.h>
17 #include <linux/jhash.h>
18 #include <linux/random.h>
19 #include <linux/slab.h>
20 #include <linux/atomic.h>
21 #include <linux/unaligned.h>
22 #include <linux/if_vlan.h>
23 #include <net/switchdev.h>
24 #include <trace/events/bridge.h>
25 #include "br_private.h"
26 
27 static const struct rhashtable_params br_fdb_rht_params = {
28 	.head_offset = offsetof(struct net_bridge_fdb_entry, rhnode),
29 	.key_offset = offsetof(struct net_bridge_fdb_entry, key),
30 	.key_len = sizeof(struct net_bridge_fdb_key),
31 	.automatic_shrinking = true,
32 };
33 
34 static struct kmem_cache *br_fdb_cache __read_mostly;
35 
36 int __init br_fdb_init(void)
37 {
38 	br_fdb_cache = KMEM_CACHE(net_bridge_fdb_entry, SLAB_HWCACHE_ALIGN);
39 	if (!br_fdb_cache)
40 		return -ENOMEM;
41 
42 	return 0;
43 }
44 
45 void br_fdb_fini(void)
46 {
47 	kmem_cache_destroy(br_fdb_cache);
48 }
49 
50 int br_fdb_hash_init(struct net_bridge *br)
51 {
52 	return rhashtable_init(&br->fdb_hash_tbl, &br_fdb_rht_params);
53 }
54 
55 void br_fdb_hash_fini(struct net_bridge *br)
56 {
57 	rhashtable_destroy(&br->fdb_hash_tbl);
58 }
59 
60 /* if topology_changing then use forward_delay (default 15 sec)
61  * otherwise keep longer (default 5 minutes)
62  */
63 static inline unsigned long hold_time(const struct net_bridge *br)
64 {
65 	return br->topology_change ? br->forward_delay : br->ageing_time;
66 }
67 
68 static inline int has_expired(const struct net_bridge *br,
69 				  const struct net_bridge_fdb_entry *fdb)
70 {
71 	return !test_bit(BR_FDB_STATIC, &fdb->flags) &&
72 	       !test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags) &&
73 	       time_before_eq(fdb->updated + hold_time(br), jiffies);
74 }
75 
76 static int fdb_to_nud(const struct net_bridge *br,
77 		      const struct net_bridge_fdb_entry *fdb)
78 {
79 	if (test_bit(BR_FDB_LOCAL, &fdb->flags))
80 		return NUD_PERMANENT;
81 	else if (test_bit(BR_FDB_STATIC, &fdb->flags))
82 		return NUD_NOARP;
83 	else if (has_expired(br, fdb))
84 		return NUD_STALE;
85 	else
86 		return NUD_REACHABLE;
87 }
88 
89 static int fdb_fill_info(struct sk_buff *skb, const struct net_bridge *br,
90 			 const struct net_bridge_fdb_entry *fdb,
91 			 u32 portid, u32 seq, int type, unsigned int flags)
92 {
93 	const struct net_bridge_port *dst = READ_ONCE(fdb->dst);
94 	unsigned long now = jiffies;
95 	struct nda_cacheinfo ci;
96 	struct nlmsghdr *nlh;
97 	struct ndmsg *ndm;
98 	u32 ext_flags = 0;
99 
100 	nlh = nlmsg_put(skb, portid, seq, type, sizeof(*ndm), flags);
101 	if (nlh == NULL)
102 		return -EMSGSIZE;
103 
104 	ndm = nlmsg_data(nlh);
105 	ndm->ndm_family	 = AF_BRIDGE;
106 	ndm->ndm_pad1    = 0;
107 	ndm->ndm_pad2    = 0;
108 	ndm->ndm_flags	 = 0;
109 	ndm->ndm_type	 = 0;
110 	ndm->ndm_ifindex = dst ? dst->dev->ifindex : br->dev->ifindex;
111 	ndm->ndm_state   = fdb_to_nud(br, fdb);
112 
113 	if (test_bit(BR_FDB_OFFLOADED, &fdb->flags))
114 		ndm->ndm_flags |= NTF_OFFLOADED;
115 	if (test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags))
116 		ndm->ndm_flags |= NTF_EXT_LEARNED;
117 	if (test_bit(BR_FDB_STICKY, &fdb->flags))
118 		ndm->ndm_flags |= NTF_STICKY;
119 	if (test_bit(BR_FDB_LOCKED, &fdb->flags))
120 		ext_flags |= NTF_EXT_LOCKED;
121 
122 	if (nla_put(skb, NDA_LLADDR, ETH_ALEN, &fdb->key.addr))
123 		goto nla_put_failure;
124 	if (nla_put_u32(skb, NDA_MASTER, br->dev->ifindex))
125 		goto nla_put_failure;
126 	if (nla_put_u32(skb, NDA_FLAGS_EXT, ext_flags))
127 		goto nla_put_failure;
128 
129 	ci.ndm_used	 = jiffies_to_clock_t(now - fdb->used);
130 	ci.ndm_confirmed = 0;
131 	ci.ndm_updated	 = jiffies_to_clock_t(now - fdb->updated);
132 	ci.ndm_refcnt	 = 0;
133 	if (nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci))
134 		goto nla_put_failure;
135 
136 	if (fdb->key.vlan_id && nla_put(skb, NDA_VLAN, sizeof(u16),
137 					&fdb->key.vlan_id))
138 		goto nla_put_failure;
139 
140 	if (test_bit(BR_FDB_NOTIFY, &fdb->flags)) {
141 		struct nlattr *nest = nla_nest_start(skb, NDA_FDB_EXT_ATTRS);
142 		u8 notify_bits = FDB_NOTIFY_BIT;
143 
144 		if (!nest)
145 			goto nla_put_failure;
146 		if (test_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags))
147 			notify_bits |= FDB_NOTIFY_INACTIVE_BIT;
148 
149 		if (nla_put_u8(skb, NFEA_ACTIVITY_NOTIFY, notify_bits)) {
150 			nla_nest_cancel(skb, nest);
151 			goto nla_put_failure;
152 		}
153 
154 		nla_nest_end(skb, nest);
155 	}
156 
157 	nlmsg_end(skb, nlh);
158 	return 0;
159 
160 nla_put_failure:
161 	nlmsg_cancel(skb, nlh);
162 	return -EMSGSIZE;
163 }
164 
165 static inline size_t fdb_nlmsg_size(void)
166 {
167 	return NLMSG_ALIGN(sizeof(struct ndmsg))
168 		+ nla_total_size(ETH_ALEN) /* NDA_LLADDR */
169 		+ nla_total_size(sizeof(u32)) /* NDA_MASTER */
170 		+ nla_total_size(sizeof(u32)) /* NDA_FLAGS_EXT */
171 		+ nla_total_size(sizeof(u16)) /* NDA_VLAN */
172 		+ nla_total_size(sizeof(struct nda_cacheinfo))
173 		+ nla_total_size(0) /* NDA_FDB_EXT_ATTRS */
174 		+ nla_total_size(sizeof(u8)); /* NFEA_ACTIVITY_NOTIFY */
175 }
176 
177 static void fdb_notify(struct net_bridge *br,
178 		       const struct net_bridge_fdb_entry *fdb, int type,
179 		       bool swdev_notify)
180 {
181 	struct net *net = dev_net(br->dev);
182 	struct sk_buff *skb;
183 	int err = -ENOBUFS;
184 
185 	if (swdev_notify)
186 		br_switchdev_fdb_notify(br, fdb, type);
187 
188 	skb = nlmsg_new(fdb_nlmsg_size(), GFP_ATOMIC);
189 	if (skb == NULL)
190 		goto errout;
191 
192 	err = fdb_fill_info(skb, br, fdb, 0, 0, type, 0);
193 	if (err < 0) {
194 		/* -EMSGSIZE implies BUG in fdb_nlmsg_size() */
195 		WARN_ON(err == -EMSGSIZE);
196 		kfree_skb(skb);
197 		goto errout;
198 	}
199 	rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
200 	return;
201 errout:
202 	rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
203 }
204 
205 static struct net_bridge_fdb_entry *fdb_find_rcu(struct rhashtable *tbl,
206 						 const unsigned char *addr,
207 						 __u16 vid)
208 {
209 	struct net_bridge_fdb_key key;
210 
211 	WARN_ON_ONCE(!rcu_read_lock_held());
212 
213 	key.vlan_id = vid;
214 	memcpy(key.addr.addr, addr, sizeof(key.addr.addr));
215 
216 	return rhashtable_lookup(tbl, &key, br_fdb_rht_params);
217 }
218 
219 /* requires bridge hash_lock */
220 static struct net_bridge_fdb_entry *br_fdb_find(struct net_bridge *br,
221 						const unsigned char *addr,
222 						__u16 vid)
223 {
224 	struct net_bridge_fdb_entry *fdb;
225 
226 	lockdep_assert_held_once(&br->hash_lock);
227 
228 	rcu_read_lock();
229 	fdb = fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
230 	rcu_read_unlock();
231 
232 	return fdb;
233 }
234 
235 struct net_device *br_fdb_find_port(const struct net_device *br_dev,
236 				    const unsigned char *addr,
237 				    __u16 vid)
238 {
239 	struct net_bridge_fdb_entry *f;
240 	struct net_device *dev = NULL;
241 	struct net_bridge *br;
242 
243 	ASSERT_RTNL();
244 
245 	if (!netif_is_bridge_master(br_dev))
246 		return NULL;
247 
248 	br = netdev_priv(br_dev);
249 	rcu_read_lock();
250 	f = br_fdb_find_rcu(br, addr, vid);
251 	if (f && f->dst)
252 		dev = f->dst->dev;
253 	rcu_read_unlock();
254 
255 	return dev;
256 }
257 EXPORT_SYMBOL_GPL(br_fdb_find_port);
258 
259 struct net_bridge_fdb_entry *br_fdb_find_rcu(struct net_bridge *br,
260 					     const unsigned char *addr,
261 					     __u16 vid)
262 {
263 	return fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
264 }
265 
266 /* When a static FDB entry is added, the mac address from the entry is
267  * added to the bridge private HW address list and all required ports
268  * are then updated with the new information.
269  * Called under RTNL.
270  */
271 static void fdb_add_hw_addr(struct net_bridge *br, const unsigned char *addr)
272 {
273 	int err;
274 	struct net_bridge_port *p;
275 
276 	ASSERT_RTNL();
277 
278 	list_for_each_entry(p, &br->port_list, list) {
279 		if (!br_promisc_port(p)) {
280 			err = dev_uc_add(p->dev, addr);
281 			if (err)
282 				goto undo;
283 		}
284 	}
285 
286 	return;
287 undo:
288 	list_for_each_entry_continue_reverse(p, &br->port_list, list) {
289 		if (!br_promisc_port(p))
290 			dev_uc_del(p->dev, addr);
291 	}
292 }
293 
294 /* When a static FDB entry is deleted, the HW address from that entry is
295  * also removed from the bridge private HW address list and updates all
296  * the ports with needed information.
297  * Called under RTNL.
298  */
299 static void fdb_del_hw_addr(struct net_bridge *br, const unsigned char *addr)
300 {
301 	struct net_bridge_port *p;
302 
303 	ASSERT_RTNL();
304 
305 	list_for_each_entry(p, &br->port_list, list) {
306 		if (!br_promisc_port(p))
307 			dev_uc_del(p->dev, addr);
308 	}
309 }
310 
311 static void fdb_delete(struct net_bridge *br, struct net_bridge_fdb_entry *f,
312 		       bool swdev_notify)
313 {
314 	trace_fdb_delete(br, f);
315 
316 	if (test_bit(BR_FDB_STATIC, &f->flags))
317 		fdb_del_hw_addr(br, f->key.addr.addr);
318 
319 	hlist_del_init_rcu(&f->fdb_node);
320 	rhashtable_remove_fast(&br->fdb_hash_tbl, &f->rhnode,
321 			       br_fdb_rht_params);
322 	if (test_and_clear_bit(BR_FDB_DYNAMIC_LEARNED, &f->flags))
323 		atomic_dec(&br->fdb_n_learned);
324 	fdb_notify(br, f, RTM_DELNEIGH, swdev_notify);
325 	kfree_rcu(f, rcu);
326 }
327 
328 /* Delete a local entry if no other port had the same address.
329  *
330  * This function should only be called on entries with BR_FDB_LOCAL set,
331  * so even with BR_FDB_ADDED_BY_USER cleared we never need to increase
332  * the accounting for dynamically learned entries again.
333  */
334 static void fdb_delete_local(struct net_bridge *br,
335 			     const struct net_bridge_port *p,
336 			     struct net_bridge_fdb_entry *f)
337 {
338 	const unsigned char *addr = f->key.addr.addr;
339 	struct net_bridge_vlan_group *vg;
340 	const struct net_bridge_vlan *v;
341 	struct net_bridge_port *op;
342 	u16 vid = f->key.vlan_id;
343 
344 	/* Maybe another port has same hw addr? */
345 	list_for_each_entry(op, &br->port_list, list) {
346 		vg = nbp_vlan_group(op);
347 		if (op != p && ether_addr_equal(op->dev->dev_addr, addr) &&
348 		    (!vid || br_vlan_find(vg, vid))) {
349 			f->dst = op;
350 			clear_bit(BR_FDB_ADDED_BY_USER, &f->flags);
351 			return;
352 		}
353 	}
354 
355 	vg = br_vlan_group(br);
356 	v = br_vlan_find(vg, vid);
357 	/* Maybe bridge device has same hw addr? */
358 	if (p && ether_addr_equal(br->dev->dev_addr, addr) &&
359 	    (!vid || (v && br_vlan_should_use(v)))) {
360 		f->dst = NULL;
361 		clear_bit(BR_FDB_ADDED_BY_USER, &f->flags);
362 		return;
363 	}
364 
365 	fdb_delete(br, f, true);
366 }
367 
368 void br_fdb_find_delete_local(struct net_bridge *br,
369 			      const struct net_bridge_port *p,
370 			      const unsigned char *addr, u16 vid)
371 {
372 	struct net_bridge_fdb_entry *f;
373 
374 	spin_lock_bh(&br->hash_lock);
375 	f = br_fdb_find(br, addr, vid);
376 	if (f && test_bit(BR_FDB_LOCAL, &f->flags) &&
377 	    !test_bit(BR_FDB_ADDED_BY_USER, &f->flags) && f->dst == p)
378 		fdb_delete_local(br, p, f);
379 	spin_unlock_bh(&br->hash_lock);
380 }
381 
382 static struct net_bridge_fdb_entry *fdb_create(struct net_bridge *br,
383 					       struct net_bridge_port *source,
384 					       const unsigned char *addr,
385 					       __u16 vid,
386 					       unsigned long flags)
387 {
388 	bool learned = !test_bit(BR_FDB_ADDED_BY_USER, &flags) &&
389 		       !test_bit(BR_FDB_LOCAL, &flags);
390 	u32 max_learned = READ_ONCE(br->fdb_max_learned);
391 	struct net_bridge_fdb_entry *fdb;
392 	int err;
393 
394 	if (likely(learned)) {
395 		int n_learned = atomic_read(&br->fdb_n_learned);
396 
397 		if (unlikely(max_learned && n_learned >= max_learned))
398 			return NULL;
399 		__set_bit(BR_FDB_DYNAMIC_LEARNED, &flags);
400 	}
401 
402 	fdb = kmem_cache_alloc(br_fdb_cache, GFP_ATOMIC);
403 	if (!fdb)
404 		return NULL;
405 
406 	memcpy(fdb->key.addr.addr, addr, ETH_ALEN);
407 	WRITE_ONCE(fdb->dst, source);
408 	fdb->key.vlan_id = vid;
409 	fdb->flags = flags;
410 	fdb->updated = fdb->used = jiffies;
411 	err = rhashtable_lookup_insert_fast(&br->fdb_hash_tbl, &fdb->rhnode,
412 					    br_fdb_rht_params);
413 	if (err) {
414 		kmem_cache_free(br_fdb_cache, fdb);
415 		return NULL;
416 	}
417 
418 	if (likely(learned))
419 		atomic_inc(&br->fdb_n_learned);
420 
421 	hlist_add_head_rcu(&fdb->fdb_node, &br->fdb_list);
422 
423 	return fdb;
424 }
425 
426 static int fdb_add_local(struct net_bridge *br, struct net_bridge_port *source,
427 			 const unsigned char *addr, u16 vid)
428 {
429 	struct net_bridge_fdb_entry *fdb;
430 
431 	if (!is_valid_ether_addr(addr))
432 		return -EINVAL;
433 
434 	fdb = br_fdb_find(br, addr, vid);
435 	if (fdb) {
436 		/* it is okay to have multiple ports with same
437 		 * address, just use the first one.
438 		 */
439 		if (test_bit(BR_FDB_LOCAL, &fdb->flags))
440 			return 0;
441 		br_warn(br, "adding interface %s with same address as a received packet (addr:%pM, vlan:%u)\n",
442 			source ? source->dev->name : br->dev->name, addr, vid);
443 		fdb_delete(br, fdb, true);
444 	}
445 
446 	fdb = fdb_create(br, source, addr, vid,
447 			 BIT(BR_FDB_LOCAL) | BIT(BR_FDB_STATIC));
448 	if (!fdb)
449 		return -ENOMEM;
450 
451 	fdb_add_hw_addr(br, addr);
452 	fdb_notify(br, fdb, RTM_NEWNEIGH, true);
453 	return 0;
454 }
455 
456 void br_fdb_changeaddr(struct net_bridge_port *p, const unsigned char *newaddr)
457 {
458 	struct net_bridge_vlan_group *vg;
459 	struct net_bridge_fdb_entry *f;
460 	struct net_bridge *br = p->br;
461 	struct net_bridge_vlan *v;
462 
463 	spin_lock_bh(&br->hash_lock);
464 	vg = nbp_vlan_group(p);
465 	hlist_for_each_entry(f, &br->fdb_list, fdb_node) {
466 		if (f->dst == p && test_bit(BR_FDB_LOCAL, &f->flags) &&
467 		    !test_bit(BR_FDB_ADDED_BY_USER, &f->flags)) {
468 			/* delete old one */
469 			fdb_delete_local(br, p, f);
470 
471 			/* if this port has no vlan information
472 			 * configured, we can safely be done at
473 			 * this point.
474 			 */
475 			if (!vg || !vg->num_vlans)
476 				goto insert;
477 		}
478 	}
479 
480 insert:
481 	/* insert new address,  may fail if invalid address or dup. */
482 	fdb_add_local(br, p, newaddr, 0);
483 
484 	if (!vg || !vg->num_vlans)
485 		goto done;
486 
487 	/* Now add entries for every VLAN configured on the port.
488 	 * This function runs under RTNL so the bitmap will not change
489 	 * from under us.
490 	 */
491 	list_for_each_entry(v, &vg->vlan_list, vlist)
492 		fdb_add_local(br, p, newaddr, v->vid);
493 
494 done:
495 	spin_unlock_bh(&br->hash_lock);
496 }
497 
498 void br_fdb_change_mac_address(struct net_bridge *br, const u8 *newaddr)
499 {
500 	struct net_bridge_vlan_group *vg;
501 	struct net_bridge_fdb_entry *f;
502 	struct net_bridge_vlan *v;
503 
504 	spin_lock_bh(&br->hash_lock);
505 
506 	/* If old entry was unassociated with any port, then delete it. */
507 	f = br_fdb_find(br, br->dev->dev_addr, 0);
508 	if (f && test_bit(BR_FDB_LOCAL, &f->flags) &&
509 	    !f->dst && !test_bit(BR_FDB_ADDED_BY_USER, &f->flags))
510 		fdb_delete_local(br, NULL, f);
511 
512 	fdb_add_local(br, NULL, newaddr, 0);
513 	vg = br_vlan_group(br);
514 	if (!vg || !vg->num_vlans)
515 		goto out;
516 	/* Now remove and add entries for every VLAN configured on the
517 	 * bridge.  This function runs under RTNL so the bitmap will not
518 	 * change from under us.
519 	 */
520 	list_for_each_entry(v, &vg->vlan_list, vlist) {
521 		if (!br_vlan_should_use(v))
522 			continue;
523 		f = br_fdb_find(br, br->dev->dev_addr, v->vid);
524 		if (f && test_bit(BR_FDB_LOCAL, &f->flags) &&
525 		    !f->dst && !test_bit(BR_FDB_ADDED_BY_USER, &f->flags))
526 			fdb_delete_local(br, NULL, f);
527 		fdb_add_local(br, NULL, newaddr, v->vid);
528 	}
529 out:
530 	spin_unlock_bh(&br->hash_lock);
531 }
532 
533 void br_fdb_cleanup(struct work_struct *work)
534 {
535 	struct net_bridge *br = container_of(work, struct net_bridge,
536 					     gc_work.work);
537 	struct net_bridge_fdb_entry *f = NULL;
538 	unsigned long delay = hold_time(br);
539 	unsigned long work_delay = delay;
540 	unsigned long now = jiffies;
541 
542 	/* this part is tricky, in order to avoid blocking learning and
543 	 * consequently forwarding, we rely on rcu to delete objects with
544 	 * delayed freeing allowing us to continue traversing
545 	 */
546 	rcu_read_lock();
547 	hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
548 		unsigned long this_timer = f->updated + delay;
549 
550 		if (test_bit(BR_FDB_STATIC, &f->flags) ||
551 		    test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &f->flags)) {
552 			if (test_bit(BR_FDB_NOTIFY, &f->flags)) {
553 				if (time_after(this_timer, now))
554 					work_delay = min(work_delay,
555 							 this_timer - now);
556 				else if (!test_and_set_bit(BR_FDB_NOTIFY_INACTIVE,
557 							   &f->flags))
558 					fdb_notify(br, f, RTM_NEWNEIGH, false);
559 			}
560 			continue;
561 		}
562 
563 		if (time_after(this_timer, now)) {
564 			work_delay = min(work_delay, this_timer - now);
565 		} else {
566 			spin_lock_bh(&br->hash_lock);
567 			if (!hlist_unhashed(&f->fdb_node))
568 				fdb_delete(br, f, true);
569 			spin_unlock_bh(&br->hash_lock);
570 		}
571 	}
572 	rcu_read_unlock();
573 
574 	/* Cleanup minimum 10 milliseconds apart */
575 	work_delay = max_t(unsigned long, work_delay, msecs_to_jiffies(10));
576 	mod_delayed_work(system_long_wq, &br->gc_work, work_delay);
577 }
578 
579 static bool __fdb_flush_matches(const struct net_bridge *br,
580 				const struct net_bridge_fdb_entry *f,
581 				const struct net_bridge_fdb_flush_desc *desc)
582 {
583 	const struct net_bridge_port *dst = READ_ONCE(f->dst);
584 	int port_ifidx = dst ? dst->dev->ifindex : br->dev->ifindex;
585 
586 	if (desc->vlan_id && desc->vlan_id != f->key.vlan_id)
587 		return false;
588 	if (desc->port_ifindex && desc->port_ifindex != port_ifidx)
589 		return false;
590 	if (desc->flags_mask && (f->flags & desc->flags_mask) != desc->flags)
591 		return false;
592 
593 	return true;
594 }
595 
596 /* Flush forwarding database entries matching the description */
597 void br_fdb_flush(struct net_bridge *br,
598 		  const struct net_bridge_fdb_flush_desc *desc)
599 {
600 	struct net_bridge_fdb_entry *f;
601 
602 	rcu_read_lock();
603 	hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
604 		if (!__fdb_flush_matches(br, f, desc))
605 			continue;
606 
607 		spin_lock_bh(&br->hash_lock);
608 		if (!hlist_unhashed(&f->fdb_node))
609 			fdb_delete(br, f, true);
610 		spin_unlock_bh(&br->hash_lock);
611 	}
612 	rcu_read_unlock();
613 }
614 
615 static unsigned long __ndm_state_to_fdb_flags(u16 ndm_state)
616 {
617 	unsigned long flags = 0;
618 
619 	if (ndm_state & NUD_PERMANENT)
620 		__set_bit(BR_FDB_LOCAL, &flags);
621 	if (ndm_state & NUD_NOARP)
622 		__set_bit(BR_FDB_STATIC, &flags);
623 
624 	return flags;
625 }
626 
627 static unsigned long __ndm_flags_to_fdb_flags(u8 ndm_flags)
628 {
629 	unsigned long flags = 0;
630 
631 	if (ndm_flags & NTF_USE)
632 		__set_bit(BR_FDB_ADDED_BY_USER, &flags);
633 	if (ndm_flags & NTF_EXT_LEARNED)
634 		__set_bit(BR_FDB_ADDED_BY_EXT_LEARN, &flags);
635 	if (ndm_flags & NTF_OFFLOADED)
636 		__set_bit(BR_FDB_OFFLOADED, &flags);
637 	if (ndm_flags & NTF_STICKY)
638 		__set_bit(BR_FDB_STICKY, &flags);
639 
640 	return flags;
641 }
642 
643 static int __fdb_flush_validate_ifindex(const struct net_bridge *br,
644 					int ifindex,
645 					struct netlink_ext_ack *extack)
646 {
647 	const struct net_device *dev;
648 
649 	dev = __dev_get_by_index(dev_net(br->dev), ifindex);
650 	if (!dev) {
651 		NL_SET_ERR_MSG_MOD(extack, "Unknown flush device ifindex");
652 		return -ENODEV;
653 	}
654 	if (!netif_is_bridge_master(dev) && !netif_is_bridge_port(dev)) {
655 		NL_SET_ERR_MSG_MOD(extack, "Flush device is not a bridge or bridge port");
656 		return -EINVAL;
657 	}
658 	if (netif_is_bridge_master(dev) && dev != br->dev) {
659 		NL_SET_ERR_MSG_MOD(extack,
660 				   "Flush bridge device does not match target bridge device");
661 		return -EINVAL;
662 	}
663 	if (netif_is_bridge_port(dev)) {
664 		struct net_bridge_port *p = br_port_get_rtnl(dev);
665 
666 		if (p->br != br) {
667 			NL_SET_ERR_MSG_MOD(extack, "Port belongs to a different bridge device");
668 			return -EINVAL;
669 		}
670 	}
671 
672 	return 0;
673 }
674 
675 static const struct nla_policy br_fdb_del_bulk_policy[NDA_MAX + 1] = {
676 	[NDA_VLAN]	= NLA_POLICY_RANGE(NLA_U16, 1, VLAN_N_VID - 2),
677 	[NDA_IFINDEX]	= NLA_POLICY_MIN(NLA_S32, 1),
678 	[NDA_NDM_STATE_MASK]	= { .type = NLA_U16 },
679 	[NDA_NDM_FLAGS_MASK]	= { .type = NLA_U8 },
680 };
681 
682 int br_fdb_delete_bulk(struct nlmsghdr *nlh, struct net_device *dev,
683 		       struct netlink_ext_ack *extack)
684 {
685 	struct net_bridge_fdb_flush_desc desc = {};
686 	struct ndmsg *ndm = nlmsg_data(nlh);
687 	struct net_bridge_port *p = NULL;
688 	struct nlattr *tb[NDA_MAX + 1];
689 	struct net_bridge *br;
690 	u8 ndm_flags;
691 	int err;
692 
693 	ndm_flags = ndm->ndm_flags & ~FDB_FLUSH_IGNORED_NDM_FLAGS;
694 
695 	err = nlmsg_parse(nlh, sizeof(*ndm), tb, NDA_MAX,
696 			  br_fdb_del_bulk_policy, extack);
697 	if (err)
698 		return err;
699 
700 	if (netif_is_bridge_master(dev)) {
701 		br = netdev_priv(dev);
702 	} else {
703 		p = br_port_get_rtnl(dev);
704 		if (!p) {
705 			NL_SET_ERR_MSG_MOD(extack, "Device is not a bridge port");
706 			return -EINVAL;
707 		}
708 		br = p->br;
709 	}
710 
711 	if (tb[NDA_VLAN])
712 		desc.vlan_id = nla_get_u16(tb[NDA_VLAN]);
713 
714 	if (ndm_flags & ~FDB_FLUSH_ALLOWED_NDM_FLAGS) {
715 		NL_SET_ERR_MSG(extack, "Unsupported fdb flush ndm flag bits set");
716 		return -EINVAL;
717 	}
718 	if (ndm->ndm_state & ~FDB_FLUSH_ALLOWED_NDM_STATES) {
719 		NL_SET_ERR_MSG(extack, "Unsupported fdb flush ndm state bits set");
720 		return -EINVAL;
721 	}
722 
723 	desc.flags |= __ndm_state_to_fdb_flags(ndm->ndm_state);
724 	desc.flags |= __ndm_flags_to_fdb_flags(ndm_flags);
725 	if (tb[NDA_NDM_STATE_MASK]) {
726 		u16 ndm_state_mask = nla_get_u16(tb[NDA_NDM_STATE_MASK]);
727 
728 		desc.flags_mask |= __ndm_state_to_fdb_flags(ndm_state_mask);
729 	}
730 	if (tb[NDA_NDM_FLAGS_MASK]) {
731 		u8 ndm_flags_mask = nla_get_u8(tb[NDA_NDM_FLAGS_MASK]);
732 
733 		desc.flags_mask |= __ndm_flags_to_fdb_flags(ndm_flags_mask);
734 	}
735 	if (tb[NDA_IFINDEX]) {
736 		int ifidx = nla_get_s32(tb[NDA_IFINDEX]);
737 
738 		err = __fdb_flush_validate_ifindex(br, ifidx, extack);
739 		if (err)
740 			return err;
741 		desc.port_ifindex = ifidx;
742 	} else if (p) {
743 		/* flush was invoked with port device and NTF_MASTER */
744 		desc.port_ifindex = p->dev->ifindex;
745 	}
746 
747 	br_debug(br, "flushing port ifindex: %d vlan id: %u flags: 0x%lx flags mask: 0x%lx\n",
748 		 desc.port_ifindex, desc.vlan_id, desc.flags, desc.flags_mask);
749 
750 	br_fdb_flush(br, &desc);
751 
752 	return 0;
753 }
754 
755 /* Flush all entries referring to a specific port.
756  * if do_all is set also flush static entries
757  * if vid is set delete all entries that match the vlan_id
758  */
759 void br_fdb_delete_by_port(struct net_bridge *br,
760 			   const struct net_bridge_port *p,
761 			   u16 vid,
762 			   int do_all)
763 {
764 	struct net_bridge_fdb_entry *f;
765 	struct hlist_node *tmp;
766 
767 	spin_lock_bh(&br->hash_lock);
768 	hlist_for_each_entry_safe(f, tmp, &br->fdb_list, fdb_node) {
769 		if (f->dst != p)
770 			continue;
771 
772 		if (!do_all)
773 			if (test_bit(BR_FDB_STATIC, &f->flags) ||
774 			    (test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &f->flags) &&
775 			     !test_bit(BR_FDB_OFFLOADED, &f->flags)) ||
776 			    (vid && f->key.vlan_id != vid))
777 				continue;
778 
779 		if (test_bit(BR_FDB_LOCAL, &f->flags))
780 			fdb_delete_local(br, p, f);
781 		else
782 			fdb_delete(br, f, true);
783 	}
784 	spin_unlock_bh(&br->hash_lock);
785 }
786 
787 #if IS_ENABLED(CONFIG_ATM_LANE)
788 /* Interface used by ATM LANE hook to test
789  * if an addr is on some other bridge port */
790 int br_fdb_test_addr(struct net_device *dev, unsigned char *addr)
791 {
792 	struct net_bridge_fdb_entry *fdb;
793 	struct net_bridge_port *port;
794 	int ret;
795 
796 	rcu_read_lock();
797 	port = br_port_get_rcu(dev);
798 	if (!port)
799 		ret = 0;
800 	else {
801 		const struct net_bridge_port *dst = NULL;
802 
803 		fdb = br_fdb_find_rcu(port->br, addr, 0);
804 		if (fdb)
805 			dst = READ_ONCE(fdb->dst);
806 
807 		ret = dst && dst->dev != dev &&
808 		      dst->state == BR_STATE_FORWARDING;
809 	}
810 	rcu_read_unlock();
811 
812 	return ret;
813 }
814 #endif /* CONFIG_ATM_LANE */
815 
816 /*
817  * Fill buffer with forwarding table records in
818  * the API format.
819  */
820 int br_fdb_fillbuf(struct net_bridge *br, void *buf,
821 		   unsigned long maxnum, unsigned long skip)
822 {
823 	struct net_bridge_fdb_entry *f;
824 	struct __fdb_entry *fe = buf;
825 	int num = 0;
826 
827 	memset(buf, 0, maxnum*sizeof(struct __fdb_entry));
828 
829 	rcu_read_lock();
830 	hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
831 		if (num >= maxnum)
832 			break;
833 
834 		if (has_expired(br, f))
835 			continue;
836 
837 		/* ignore pseudo entry for local MAC address */
838 		if (!f->dst)
839 			continue;
840 
841 		if (skip) {
842 			--skip;
843 			continue;
844 		}
845 
846 		/* convert from internal format to API */
847 		memcpy(fe->mac_addr, f->key.addr.addr, ETH_ALEN);
848 
849 		/* due to ABI compat need to split into hi/lo */
850 		fe->port_no = f->dst->port_no;
851 		fe->port_hi = f->dst->port_no >> 8;
852 
853 		fe->is_local = test_bit(BR_FDB_LOCAL, &f->flags);
854 		if (!test_bit(BR_FDB_STATIC, &f->flags))
855 			fe->ageing_timer_value = jiffies_delta_to_clock_t(jiffies - f->updated);
856 		++fe;
857 		++num;
858 	}
859 	rcu_read_unlock();
860 
861 	return num;
862 }
863 
864 /* Add entry for local address of interface */
865 int br_fdb_add_local(struct net_bridge *br, struct net_bridge_port *source,
866 		     const unsigned char *addr, u16 vid)
867 {
868 	int ret;
869 
870 	spin_lock_bh(&br->hash_lock);
871 	ret = fdb_add_local(br, source, addr, vid);
872 	spin_unlock_bh(&br->hash_lock);
873 	return ret;
874 }
875 
876 /* returns true if the fdb was modified */
877 static bool __fdb_mark_active(struct net_bridge_fdb_entry *fdb)
878 {
879 	return !!(test_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags) &&
880 		  test_and_clear_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags));
881 }
882 
883 void br_fdb_update(struct net_bridge *br, struct net_bridge_port *source,
884 		   const unsigned char *addr, u16 vid, unsigned long flags)
885 {
886 	struct net_bridge_fdb_entry *fdb;
887 
888 	/* some users want to always flood. */
889 	if (hold_time(br) == 0)
890 		return;
891 
892 	fdb = fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
893 	if (likely(fdb)) {
894 		/* attempt to update an entry for a local interface */
895 		if (unlikely(test_bit(BR_FDB_LOCAL, &fdb->flags))) {
896 			if (net_ratelimit())
897 				br_warn(br, "received packet on %s with own address as source address (addr:%pM, vlan:%u)\n",
898 					source->dev->name, addr, vid);
899 		} else {
900 			unsigned long now = jiffies;
901 			bool fdb_modified = false;
902 
903 			if (now != fdb->updated) {
904 				fdb->updated = now;
905 				fdb_modified = __fdb_mark_active(fdb);
906 			}
907 
908 			/* fastpath: update of existing entry */
909 			if (unlikely(source != READ_ONCE(fdb->dst) &&
910 				     !test_bit(BR_FDB_STICKY, &fdb->flags))) {
911 				br_switchdev_fdb_notify(br, fdb, RTM_DELNEIGH);
912 				WRITE_ONCE(fdb->dst, source);
913 				fdb_modified = true;
914 				/* Take over HW learned entry */
915 				if (unlikely(test_bit(BR_FDB_ADDED_BY_EXT_LEARN,
916 						      &fdb->flags)))
917 					clear_bit(BR_FDB_ADDED_BY_EXT_LEARN,
918 						  &fdb->flags);
919 				/* Clear locked flag when roaming to an
920 				 * unlocked port.
921 				 */
922 				if (unlikely(test_bit(BR_FDB_LOCKED, &fdb->flags)))
923 					clear_bit(BR_FDB_LOCKED, &fdb->flags);
924 			}
925 
926 			if (unlikely(test_bit(BR_FDB_ADDED_BY_USER, &flags))) {
927 				set_bit(BR_FDB_ADDED_BY_USER, &fdb->flags);
928 				if (test_and_clear_bit(BR_FDB_DYNAMIC_LEARNED,
929 						       &fdb->flags))
930 					atomic_dec(&br->fdb_n_learned);
931 			}
932 			if (unlikely(fdb_modified)) {
933 				trace_br_fdb_update(br, source, addr, vid, flags);
934 				fdb_notify(br, fdb, RTM_NEWNEIGH, true);
935 			}
936 		}
937 	} else {
938 		spin_lock(&br->hash_lock);
939 		fdb = fdb_create(br, source, addr, vid, flags);
940 		if (fdb) {
941 			trace_br_fdb_update(br, source, addr, vid, flags);
942 			fdb_notify(br, fdb, RTM_NEWNEIGH, true);
943 		}
944 		/* else  we lose race and someone else inserts
945 		 * it first, don't bother updating
946 		 */
947 		spin_unlock(&br->hash_lock);
948 	}
949 }
950 
951 /* Dump information about entries, in response to GETNEIGH */
952 int br_fdb_dump(struct sk_buff *skb,
953 		struct netlink_callback *cb,
954 		struct net_device *dev,
955 		struct net_device *filter_dev,
956 		int *idx)
957 {
958 	struct net_bridge *br = netdev_priv(dev);
959 	struct net_bridge_fdb_entry *f;
960 	int err = 0;
961 
962 	if (!netif_is_bridge_master(dev))
963 		return err;
964 
965 	if (!filter_dev) {
966 		err = ndo_dflt_fdb_dump(skb, cb, dev, NULL, idx);
967 		if (err < 0)
968 			return err;
969 	}
970 
971 	rcu_read_lock();
972 	hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
973 		if (*idx < cb->args[2])
974 			goto skip;
975 		if (filter_dev && (!f->dst || f->dst->dev != filter_dev)) {
976 			if (filter_dev != dev)
977 				goto skip;
978 			/* !f->dst is a special case for bridge
979 			 * It means the MAC belongs to the bridge
980 			 * Therefore need a little more filtering
981 			 * we only want to dump the !f->dst case
982 			 */
983 			if (f->dst)
984 				goto skip;
985 		}
986 		if (!filter_dev && f->dst)
987 			goto skip;
988 
989 		err = fdb_fill_info(skb, br, f,
990 				    NETLINK_CB(cb->skb).portid,
991 				    cb->nlh->nlmsg_seq,
992 				    RTM_NEWNEIGH,
993 				    NLM_F_MULTI);
994 		if (err < 0)
995 			break;
996 skip:
997 		*idx += 1;
998 	}
999 	rcu_read_unlock();
1000 
1001 	return err;
1002 }
1003 
1004 int br_fdb_get(struct sk_buff *skb,
1005 	       struct nlattr *tb[],
1006 	       struct net_device *dev,
1007 	       const unsigned char *addr,
1008 	       u16 vid, u32 portid, u32 seq,
1009 	       struct netlink_ext_ack *extack)
1010 {
1011 	struct net_bridge *br = netdev_priv(dev);
1012 	struct net_bridge_fdb_entry *f;
1013 	int err = 0;
1014 
1015 	rcu_read_lock();
1016 	f = br_fdb_find_rcu(br, addr, vid);
1017 	if (!f) {
1018 		NL_SET_ERR_MSG(extack, "Fdb entry not found");
1019 		err = -ENOENT;
1020 		goto errout;
1021 	}
1022 
1023 	err = fdb_fill_info(skb, br, f, portid, seq,
1024 			    RTM_NEWNEIGH, 0);
1025 errout:
1026 	rcu_read_unlock();
1027 	return err;
1028 }
1029 
1030 /* returns true if the fdb is modified */
1031 static bool fdb_handle_notify(struct net_bridge_fdb_entry *fdb, u8 notify)
1032 {
1033 	bool modified = false;
1034 
1035 	/* allow to mark an entry as inactive, usually done on creation */
1036 	if ((notify & FDB_NOTIFY_INACTIVE_BIT) &&
1037 	    !test_and_set_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags))
1038 		modified = true;
1039 
1040 	if ((notify & FDB_NOTIFY_BIT) &&
1041 	    !test_and_set_bit(BR_FDB_NOTIFY, &fdb->flags)) {
1042 		/* enabled activity tracking */
1043 		modified = true;
1044 	} else if (!(notify & FDB_NOTIFY_BIT) &&
1045 		   test_and_clear_bit(BR_FDB_NOTIFY, &fdb->flags)) {
1046 		/* disabled activity tracking, clear notify state */
1047 		clear_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags);
1048 		modified = true;
1049 	}
1050 
1051 	return modified;
1052 }
1053 
1054 /* Update (create or replace) forwarding database entry */
1055 static int fdb_add_entry(struct net_bridge *br, struct net_bridge_port *source,
1056 			 const u8 *addr, struct ndmsg *ndm, u16 flags, u16 vid,
1057 			 struct nlattr *nfea_tb[])
1058 {
1059 	bool is_sticky = !!(ndm->ndm_flags & NTF_STICKY);
1060 	bool refresh = !nfea_tb[NFEA_DONT_REFRESH];
1061 	struct net_bridge_fdb_entry *fdb;
1062 	u16 state = ndm->ndm_state;
1063 	bool modified = false;
1064 	u8 notify = 0;
1065 
1066 	/* If the port cannot learn allow only local and static entries */
1067 	if (source && !(state & NUD_PERMANENT) && !(state & NUD_NOARP) &&
1068 	    !(source->state == BR_STATE_LEARNING ||
1069 	      source->state == BR_STATE_FORWARDING))
1070 		return -EPERM;
1071 
1072 	if (!source && !(state & NUD_PERMANENT)) {
1073 		pr_info("bridge: RTM_NEWNEIGH %s without NUD_PERMANENT\n",
1074 			br->dev->name);
1075 		return -EINVAL;
1076 	}
1077 
1078 	if (is_sticky && (state & NUD_PERMANENT))
1079 		return -EINVAL;
1080 
1081 	if (nfea_tb[NFEA_ACTIVITY_NOTIFY]) {
1082 		notify = nla_get_u8(nfea_tb[NFEA_ACTIVITY_NOTIFY]);
1083 		if ((notify & ~BR_FDB_NOTIFY_SETTABLE_BITS) ||
1084 		    (notify & BR_FDB_NOTIFY_SETTABLE_BITS) == FDB_NOTIFY_INACTIVE_BIT)
1085 			return -EINVAL;
1086 	}
1087 
1088 	fdb = br_fdb_find(br, addr, vid);
1089 	if (fdb == NULL) {
1090 		if (!(flags & NLM_F_CREATE))
1091 			return -ENOENT;
1092 
1093 		fdb = fdb_create(br, source, addr, vid,
1094 				 BIT(BR_FDB_ADDED_BY_USER));
1095 		if (!fdb)
1096 			return -ENOMEM;
1097 
1098 		modified = true;
1099 	} else {
1100 		if (flags & NLM_F_EXCL)
1101 			return -EEXIST;
1102 
1103 		if (READ_ONCE(fdb->dst) != source) {
1104 			WRITE_ONCE(fdb->dst, source);
1105 			modified = true;
1106 		}
1107 
1108 		set_bit(BR_FDB_ADDED_BY_USER, &fdb->flags);
1109 		if (test_and_clear_bit(BR_FDB_DYNAMIC_LEARNED, &fdb->flags))
1110 			atomic_dec(&br->fdb_n_learned);
1111 	}
1112 
1113 	if (fdb_to_nud(br, fdb) != state) {
1114 		if (state & NUD_PERMANENT) {
1115 			set_bit(BR_FDB_LOCAL, &fdb->flags);
1116 			if (!test_and_set_bit(BR_FDB_STATIC, &fdb->flags))
1117 				fdb_add_hw_addr(br, addr);
1118 		} else if (state & NUD_NOARP) {
1119 			clear_bit(BR_FDB_LOCAL, &fdb->flags);
1120 			if (!test_and_set_bit(BR_FDB_STATIC, &fdb->flags))
1121 				fdb_add_hw_addr(br, addr);
1122 		} else {
1123 			clear_bit(BR_FDB_LOCAL, &fdb->flags);
1124 			if (test_and_clear_bit(BR_FDB_STATIC, &fdb->flags))
1125 				fdb_del_hw_addr(br, addr);
1126 		}
1127 
1128 		modified = true;
1129 	}
1130 
1131 	if (is_sticky != test_bit(BR_FDB_STICKY, &fdb->flags)) {
1132 		change_bit(BR_FDB_STICKY, &fdb->flags);
1133 		modified = true;
1134 	}
1135 
1136 	if (test_and_clear_bit(BR_FDB_LOCKED, &fdb->flags))
1137 		modified = true;
1138 
1139 	if (fdb_handle_notify(fdb, notify))
1140 		modified = true;
1141 
1142 	fdb->used = jiffies;
1143 	if (modified) {
1144 		if (refresh)
1145 			fdb->updated = jiffies;
1146 		fdb_notify(br, fdb, RTM_NEWNEIGH, true);
1147 	}
1148 
1149 	return 0;
1150 }
1151 
1152 static int __br_fdb_add(struct ndmsg *ndm, struct net_bridge *br,
1153 			struct net_bridge_port *p, const unsigned char *addr,
1154 			u16 nlh_flags, u16 vid, struct nlattr *nfea_tb[],
1155 			bool *notified, struct netlink_ext_ack *extack)
1156 {
1157 	int err = 0;
1158 
1159 	if (ndm->ndm_flags & NTF_USE) {
1160 		if (!p) {
1161 			pr_info("bridge: RTM_NEWNEIGH %s with NTF_USE is not supported\n",
1162 				br->dev->name);
1163 			return -EINVAL;
1164 		}
1165 		if (!nbp_state_should_learn(p))
1166 			return 0;
1167 
1168 		local_bh_disable();
1169 		rcu_read_lock();
1170 		br_fdb_update(br, p, addr, vid, BIT(BR_FDB_ADDED_BY_USER));
1171 		rcu_read_unlock();
1172 		local_bh_enable();
1173 	} else if (ndm->ndm_flags & NTF_EXT_LEARNED) {
1174 		if (!p && !(ndm->ndm_state & NUD_PERMANENT)) {
1175 			NL_SET_ERR_MSG_MOD(extack,
1176 					   "FDB entry towards bridge must be permanent");
1177 			return -EINVAL;
1178 		}
1179 		err = br_fdb_external_learn_add(br, p, addr, vid, false, true);
1180 	} else {
1181 		spin_lock_bh(&br->hash_lock);
1182 		err = fdb_add_entry(br, p, addr, ndm, nlh_flags, vid, nfea_tb);
1183 		spin_unlock_bh(&br->hash_lock);
1184 	}
1185 
1186 	if (!err)
1187 		*notified = true;
1188 	return err;
1189 }
1190 
1191 static const struct nla_policy br_nda_fdb_pol[NFEA_MAX + 1] = {
1192 	[NFEA_ACTIVITY_NOTIFY]	= { .type = NLA_U8 },
1193 	[NFEA_DONT_REFRESH]	= { .type = NLA_FLAG },
1194 };
1195 
1196 /* Add new permanent fdb entry with RTM_NEWNEIGH */
1197 int br_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
1198 	       struct net_device *dev,
1199 	       const unsigned char *addr, u16 vid, u16 nlh_flags,
1200 	       bool *notified, struct netlink_ext_ack *extack)
1201 {
1202 	struct nlattr *nfea_tb[NFEA_MAX + 1], *attr;
1203 	struct net_bridge_vlan_group *vg;
1204 	struct net_bridge_port *p = NULL;
1205 	struct net_bridge_vlan *v;
1206 	struct net_bridge *br = NULL;
1207 	u32 ext_flags = 0;
1208 	int err = 0;
1209 
1210 	trace_br_fdb_add(ndm, dev, addr, vid, nlh_flags);
1211 
1212 	if (!(ndm->ndm_state & (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE))) {
1213 		pr_info("bridge: RTM_NEWNEIGH with invalid state %#x\n", ndm->ndm_state);
1214 		return -EINVAL;
1215 	}
1216 
1217 	if (is_zero_ether_addr(addr)) {
1218 		pr_info("bridge: RTM_NEWNEIGH with invalid ether address\n");
1219 		return -EINVAL;
1220 	}
1221 
1222 	if (netif_is_bridge_master(dev)) {
1223 		br = netdev_priv(dev);
1224 		vg = br_vlan_group(br);
1225 	} else {
1226 		p = br_port_get_rtnl(dev);
1227 		if (!p) {
1228 			pr_info("bridge: RTM_NEWNEIGH %s not a bridge port\n",
1229 				dev->name);
1230 			return -EINVAL;
1231 		}
1232 		br = p->br;
1233 		vg = nbp_vlan_group(p);
1234 	}
1235 
1236 	if (tb[NDA_FLAGS_EXT])
1237 		ext_flags = nla_get_u32(tb[NDA_FLAGS_EXT]);
1238 
1239 	if (ext_flags & NTF_EXT_LOCKED) {
1240 		NL_SET_ERR_MSG_MOD(extack, "Cannot add FDB entry with \"locked\" flag set");
1241 		return -EINVAL;
1242 	}
1243 
1244 	if (tb[NDA_FDB_EXT_ATTRS]) {
1245 		attr = tb[NDA_FDB_EXT_ATTRS];
1246 		err = nla_parse_nested(nfea_tb, NFEA_MAX, attr,
1247 				       br_nda_fdb_pol, extack);
1248 		if (err)
1249 			return err;
1250 	} else {
1251 		memset(nfea_tb, 0, sizeof(struct nlattr *) * (NFEA_MAX + 1));
1252 	}
1253 
1254 	if (vid) {
1255 		v = br_vlan_find(vg, vid);
1256 		if (!v || !br_vlan_should_use(v)) {
1257 			pr_info("bridge: RTM_NEWNEIGH with unconfigured vlan %d on %s\n", vid, dev->name);
1258 			return -EINVAL;
1259 		}
1260 
1261 		/* VID was specified, so use it. */
1262 		err = __br_fdb_add(ndm, br, p, addr, nlh_flags, vid, nfea_tb,
1263 				   notified, extack);
1264 	} else {
1265 		err = __br_fdb_add(ndm, br, p, addr, nlh_flags, 0, nfea_tb,
1266 				   notified, extack);
1267 		if (err || !vg || !vg->num_vlans)
1268 			goto out;
1269 
1270 		/* We have vlans configured on this port and user didn't
1271 		 * specify a VLAN.  To be nice, add/update entry for every
1272 		 * vlan on this port.
1273 		 */
1274 		list_for_each_entry(v, &vg->vlan_list, vlist) {
1275 			if (!br_vlan_should_use(v))
1276 				continue;
1277 			err = __br_fdb_add(ndm, br, p, addr, nlh_flags, v->vid,
1278 					   nfea_tb, notified, extack);
1279 			if (err)
1280 				goto out;
1281 		}
1282 	}
1283 
1284 out:
1285 	return err;
1286 }
1287 
1288 static int fdb_delete_by_addr_and_port(struct net_bridge *br,
1289 				       const struct net_bridge_port *p,
1290 				       const u8 *addr, u16 vlan, bool *notified)
1291 {
1292 	struct net_bridge_fdb_entry *fdb;
1293 
1294 	fdb = br_fdb_find(br, addr, vlan);
1295 	if (!fdb || READ_ONCE(fdb->dst) != p)
1296 		return -ENOENT;
1297 
1298 	fdb_delete(br, fdb, true);
1299 	*notified = true;
1300 
1301 	return 0;
1302 }
1303 
1304 static int __br_fdb_delete(struct net_bridge *br,
1305 			   const struct net_bridge_port *p,
1306 			   const unsigned char *addr, u16 vid, bool *notified)
1307 {
1308 	int err;
1309 
1310 	spin_lock_bh(&br->hash_lock);
1311 	err = fdb_delete_by_addr_and_port(br, p, addr, vid, notified);
1312 	spin_unlock_bh(&br->hash_lock);
1313 
1314 	return err;
1315 }
1316 
1317 /* Remove neighbor entry with RTM_DELNEIGH */
1318 int br_fdb_delete(struct ndmsg *ndm, struct nlattr *tb[],
1319 		  struct net_device *dev,
1320 		  const unsigned char *addr, u16 vid, bool *notified,
1321 		  struct netlink_ext_ack *extack)
1322 {
1323 	struct net_bridge_vlan_group *vg;
1324 	struct net_bridge_port *p = NULL;
1325 	struct net_bridge *br;
1326 	int err;
1327 
1328 	if (netif_is_bridge_master(dev)) {
1329 		br = netdev_priv(dev);
1330 		vg = br_vlan_group(br);
1331 	} else {
1332 		p = br_port_get_rtnl(dev);
1333 		if (!p) {
1334 			pr_info("bridge: RTM_DELNEIGH %s not a bridge port\n",
1335 				dev->name);
1336 			return -EINVAL;
1337 		}
1338 		vg = nbp_vlan_group(p);
1339 		br = p->br;
1340 	}
1341 
1342 	if (vid) {
1343 		err = __br_fdb_delete(br, p, addr, vid, notified);
1344 	} else {
1345 		struct net_bridge_vlan *v;
1346 
1347 		err = -ENOENT;
1348 		err &= __br_fdb_delete(br, p, addr, 0, notified);
1349 		if (!vg || !vg->num_vlans)
1350 			return err;
1351 
1352 		list_for_each_entry(v, &vg->vlan_list, vlist) {
1353 			if (!br_vlan_should_use(v))
1354 				continue;
1355 			err &= __br_fdb_delete(br, p, addr, v->vid, notified);
1356 		}
1357 	}
1358 
1359 	return err;
1360 }
1361 
1362 int br_fdb_sync_static(struct net_bridge *br, struct net_bridge_port *p)
1363 {
1364 	struct net_bridge_fdb_entry *f, *tmp;
1365 	int err = 0;
1366 
1367 	ASSERT_RTNL();
1368 
1369 	/* the key here is that static entries change only under rtnl */
1370 	rcu_read_lock();
1371 	hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
1372 		/* We only care for static entries */
1373 		if (!test_bit(BR_FDB_STATIC, &f->flags))
1374 			continue;
1375 		err = dev_uc_add(p->dev, f->key.addr.addr);
1376 		if (err)
1377 			goto rollback;
1378 	}
1379 done:
1380 	rcu_read_unlock();
1381 
1382 	return err;
1383 
1384 rollback:
1385 	hlist_for_each_entry_rcu(tmp, &br->fdb_list, fdb_node) {
1386 		/* We only care for static entries */
1387 		if (!test_bit(BR_FDB_STATIC, &tmp->flags))
1388 			continue;
1389 		if (tmp == f)
1390 			break;
1391 		dev_uc_del(p->dev, tmp->key.addr.addr);
1392 	}
1393 
1394 	goto done;
1395 }
1396 
1397 void br_fdb_unsync_static(struct net_bridge *br, struct net_bridge_port *p)
1398 {
1399 	struct net_bridge_fdb_entry *f;
1400 
1401 	ASSERT_RTNL();
1402 
1403 	rcu_read_lock();
1404 	hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
1405 		/* We only care for static entries */
1406 		if (!test_bit(BR_FDB_STATIC, &f->flags))
1407 			continue;
1408 
1409 		dev_uc_del(p->dev, f->key.addr.addr);
1410 	}
1411 	rcu_read_unlock();
1412 }
1413 
1414 int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p,
1415 			      const unsigned char *addr, u16 vid, bool locked,
1416 			      bool swdev_notify)
1417 {
1418 	struct net_bridge_fdb_entry *fdb;
1419 	bool modified = false;
1420 	int err = 0;
1421 
1422 	trace_br_fdb_external_learn_add(br, p, addr, vid);
1423 
1424 	if (locked && (!p || !(p->flags & BR_PORT_MAB)))
1425 		return -EINVAL;
1426 
1427 	spin_lock_bh(&br->hash_lock);
1428 
1429 	fdb = br_fdb_find(br, addr, vid);
1430 	if (!fdb) {
1431 		unsigned long flags = BIT(BR_FDB_ADDED_BY_EXT_LEARN);
1432 
1433 		if (swdev_notify)
1434 			flags |= BIT(BR_FDB_ADDED_BY_USER);
1435 
1436 		if (!p)
1437 			flags |= BIT(BR_FDB_LOCAL);
1438 
1439 		if (locked)
1440 			flags |= BIT(BR_FDB_LOCKED);
1441 
1442 		fdb = fdb_create(br, p, addr, vid, flags);
1443 		if (!fdb) {
1444 			err = -ENOMEM;
1445 			goto err_unlock;
1446 		}
1447 		fdb_notify(br, fdb, RTM_NEWNEIGH, swdev_notify);
1448 	} else {
1449 		if (locked &&
1450 		    (!test_bit(BR_FDB_LOCKED, &fdb->flags) ||
1451 		     READ_ONCE(fdb->dst) != p)) {
1452 			err = -EINVAL;
1453 			goto err_unlock;
1454 		}
1455 
1456 		fdb->updated = jiffies;
1457 
1458 		if (READ_ONCE(fdb->dst) != p) {
1459 			WRITE_ONCE(fdb->dst, p);
1460 			modified = true;
1461 		}
1462 
1463 		if (test_and_set_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags)) {
1464 			/* Refresh entry */
1465 			fdb->used = jiffies;
1466 		} else {
1467 			modified = true;
1468 		}
1469 
1470 		if (locked != test_bit(BR_FDB_LOCKED, &fdb->flags)) {
1471 			change_bit(BR_FDB_LOCKED, &fdb->flags);
1472 			modified = true;
1473 		}
1474 
1475 		if (swdev_notify)
1476 			set_bit(BR_FDB_ADDED_BY_USER, &fdb->flags);
1477 
1478 		if (!p)
1479 			set_bit(BR_FDB_LOCAL, &fdb->flags);
1480 
1481 		if ((swdev_notify || !p) &&
1482 		    test_and_clear_bit(BR_FDB_DYNAMIC_LEARNED, &fdb->flags))
1483 			atomic_dec(&br->fdb_n_learned);
1484 
1485 		if (modified)
1486 			fdb_notify(br, fdb, RTM_NEWNEIGH, swdev_notify);
1487 	}
1488 
1489 err_unlock:
1490 	spin_unlock_bh(&br->hash_lock);
1491 
1492 	return err;
1493 }
1494 
1495 int br_fdb_external_learn_del(struct net_bridge *br, struct net_bridge_port *p,
1496 			      const unsigned char *addr, u16 vid,
1497 			      bool swdev_notify)
1498 {
1499 	struct net_bridge_fdb_entry *fdb;
1500 	int err = 0;
1501 
1502 	spin_lock_bh(&br->hash_lock);
1503 
1504 	fdb = br_fdb_find(br, addr, vid);
1505 	if (fdb && test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags))
1506 		fdb_delete(br, fdb, swdev_notify);
1507 	else
1508 		err = -ENOENT;
1509 
1510 	spin_unlock_bh(&br->hash_lock);
1511 
1512 	return err;
1513 }
1514 
1515 void br_fdb_offloaded_set(struct net_bridge *br, struct net_bridge_port *p,
1516 			  const unsigned char *addr, u16 vid, bool offloaded)
1517 {
1518 	struct net_bridge_fdb_entry *fdb;
1519 
1520 	spin_lock_bh(&br->hash_lock);
1521 
1522 	fdb = br_fdb_find(br, addr, vid);
1523 	if (fdb && offloaded != test_bit(BR_FDB_OFFLOADED, &fdb->flags))
1524 		change_bit(BR_FDB_OFFLOADED, &fdb->flags);
1525 
1526 	spin_unlock_bh(&br->hash_lock);
1527 }
1528 
1529 void br_fdb_clear_offload(const struct net_device *dev, u16 vid)
1530 {
1531 	struct net_bridge_fdb_entry *f;
1532 	struct net_bridge_port *p;
1533 
1534 	ASSERT_RTNL();
1535 
1536 	p = br_port_get_rtnl(dev);
1537 	if (!p)
1538 		return;
1539 
1540 	spin_lock_bh(&p->br->hash_lock);
1541 	hlist_for_each_entry(f, &p->br->fdb_list, fdb_node) {
1542 		if (f->dst == p && f->key.vlan_id == vid)
1543 			clear_bit(BR_FDB_OFFLOADED, &f->flags);
1544 	}
1545 	spin_unlock_bh(&p->br->hash_lock);
1546 }
1547 EXPORT_SYMBOL_GPL(br_fdb_clear_offload);
1548