net/bridge/br_fdb.c

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