Pileus Git - ~andy/linux/blob - net/bridge/br_fdb.c

   1 /*
   2  *      Forwarding database
   3  *      Linux ethernet bridge
   4  *
   5  *      Authors:
   6  *      Lennert Buytenhek               <buytenh@gnu.org>
   7  *
   8  *      This program is free software; you can redistribute it and/or
   9  *      modify it under the terms of the GNU General Public License
  10  *      as published by the Free Software Foundation; either version
  11  *      2 of the License, or (at your option) any later version.
  12  */
  13
  14 #include <linux/kernel.h>
  15 #include <linux/init.h>
  16 #include <linux/rculist.h>
  17 #include <linux/spinlock.h>
  18 #include <linux/times.h>
  19 #include <linux/netdevice.h>
  20 #include <linux/etherdevice.h>
  21 #include <linux/jhash.h>
  22 #include <linux/random.h>
  23 #include <linux/slab.h>
  24 #include <linux/atomic.h>
  25 #include <asm/unaligned.h>
  26 #include <linux/if_vlan.h>
  27 #include "br_private.h"
  28
  29 static struct kmem_cache *br_fdb_cache __read_mostly;
  30 static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
  31                       const unsigned char *addr);
  32 static void fdb_notify(struct net_bridge *br,
  33                        const struct net_bridge_fdb_entry *, int);
  34
  35 static u32 fdb_salt __read_mostly;
  36
  37 int __init br_fdb_init(void)
  38 {
  39         br_fdb_cache = kmem_cache_create("bridge_fdb_cache",
  40                                          sizeof(struct net_bridge_fdb_entry),
  41                                          0,
  42                                          SLAB_HWCACHE_ALIGN, NULL);
  43         if (!br_fdb_cache)
  44                 return -ENOMEM;
  45
  46         get_random_bytes(&fdb_salt, sizeof(fdb_salt));
  47         return 0;
  48 }
  49
  50 void br_fdb_fini(void)
  51 {
  52         kmem_cache_destroy(br_fdb_cache);
  53 }
  54
  55
  56 /* if topology_changing then use forward_delay (default 15 sec)
  57  * otherwise keep longer (default 5 minutes)
  58  */
  59 static inline unsigned long hold_time(const struct net_bridge *br)
  60 {
  61         return br->topology_change ? br->forward_delay : br->ageing_time;
  62 }
  63
  64 static inline int has_expired(const struct net_bridge *br,
  65                                   const struct net_bridge_fdb_entry *fdb)
  66 {
  67         return !fdb->is_static &&
  68                 time_before_eq(fdb->updated + hold_time(br), jiffies);
  69 }
  70
  71 static inline int br_mac_hash(const unsigned char *mac, __u16 vid)
  72 {
  73         /* use 1 byte of OUI and 3 bytes of NIC */
  74         u32 key = get_unaligned((u32 *)(mac + 2));
  75         return jhash_2words(key, vid, fdb_salt) & (BR_HASH_SIZE - 1);
  76 }
  77
  78 static void fdb_rcu_free(struct rcu_head *head)
  79 {
  80         struct net_bridge_fdb_entry *ent
  81                 = container_of(head, struct net_bridge_fdb_entry, rcu);
  82         kmem_cache_free(br_fdb_cache, ent);
  83 }
  84
  85 static void fdb_delete(struct net_bridge *br, struct net_bridge_fdb_entry *f)
  86 {
  87         hlist_del_rcu(&f->hlist);
  88         fdb_notify(br, f, RTM_DELNEIGH);
  89         call_rcu(&f->rcu, fdb_rcu_free);
  90 }
  91
  92 void br_fdb_changeaddr(struct net_bridge_port *p, const unsigned char *newaddr)
  93 {
  94         struct net_bridge *br = p->br;
  95         int i;
  96
  97         spin_lock_bh(&br->hash_lock);
  98
  99         /* Search all chains since old address/hash is unknown */
 100         for (i = 0; i < BR_HASH_SIZE; i++) {
 101                 struct hlist_node *h;
 102                 hlist_for_each(h, &br->hash[i]) {
 103                         struct net_bridge_fdb_entry *f;
 104
 105                         f = hlist_entry(h, struct net_bridge_fdb_entry, hlist);
 106                         if (f->dst == p && f->is_local) {
 107                                 /* maybe another port has same hw addr? */
 108                                 struct net_bridge_port *op;
 109                                 list_for_each_entry(op, &br->port_list, list) {
 110                                         if (op != p &&
 111                                             ether_addr_equal(op->dev->dev_addr,
 112                                                              f->addr.addr)) {
 113                                                 f->dst = op;
 114                                                 goto insert;
 115                                         }
 116                                 }
 117
 118                                 /* delete old one */
 119                                 fdb_delete(br, f);
 120                                 goto insert;
 121                         }
 122                 }
 123         }
 124  insert:
 125         /* insert new address,  may fail if invalid address or dup. */
 126         fdb_insert(br, p, newaddr);
 127
 128         spin_unlock_bh(&br->hash_lock);
 129 }
 130
 131 void br_fdb_change_mac_address(struct net_bridge *br, const u8 *newaddr)
 132 {
 133         struct net_bridge_fdb_entry *f;
 134
 135         /* If old entry was unassociated with any port, then delete it. */
 136         f = __br_fdb_get(br, br->dev->dev_addr, 0);
 137         if (f && f->is_local && !f->dst)
 138                 fdb_delete(br, f);
 139
 140         fdb_insert(br, NULL, newaddr);
 141 }
 142
 143 void br_fdb_cleanup(unsigned long _data)
 144 {
 145         struct net_bridge *br = (struct net_bridge *)_data;
 146         unsigned long delay = hold_time(br);
 147         unsigned long next_timer = jiffies + br->ageing_time;
 148         int i;
 149
 150         spin_lock(&br->hash_lock);
 151         for (i = 0; i < BR_HASH_SIZE; i++) {
 152                 struct net_bridge_fdb_entry *f;
 153                 struct hlist_node *h, *n;
 154
 155                 hlist_for_each_entry_safe(f, h, n, &br->hash[i], hlist) {
 156                         unsigned long this_timer;
 157                         if (f->is_static)
 158                                 continue;
 159                         this_timer = f->updated + delay;
 160                         if (time_before_eq(this_timer, jiffies))
 161                                 fdb_delete(br, f);
 162                         else if (time_before(this_timer, next_timer))
 163                                 next_timer = this_timer;
 164                 }
 165         }
 166         spin_unlock(&br->hash_lock);
 167
 168         mod_timer(&br->gc_timer, round_jiffies_up(next_timer));
 169 }
 170
 171 /* Completely flush all dynamic entries in forwarding database.*/
 172 void br_fdb_flush(struct net_bridge *br)
 173 {
 174         int i;
 175
 176         spin_lock_bh(&br->hash_lock);
 177         for (i = 0; i < BR_HASH_SIZE; i++) {
 178                 struct net_bridge_fdb_entry *f;
 179                 struct hlist_node *h, *n;
 180                 hlist_for_each_entry_safe(f, h, n, &br->hash[i], hlist) {
 181                         if (!f->is_static)
 182                                 fdb_delete(br, f);
 183                 }
 184         }
 185         spin_unlock_bh(&br->hash_lock);
 186 }
 187
 188 /* Flush all entries referring to a specific port.
 189  * if do_all is set also flush static entries
 190  */
 191 void br_fdb_delete_by_port(struct net_bridge *br,
 192                            const struct net_bridge_port *p,
 193                            int do_all)
 194 {
 195         int i;
 196
 197         spin_lock_bh(&br->hash_lock);
 198         for (i = 0; i < BR_HASH_SIZE; i++) {
 199                 struct hlist_node *h, *g;
 200
 201                 hlist_for_each_safe(h, g, &br->hash[i]) {
 202                         struct net_bridge_fdb_entry *f
 203                                 = hlist_entry(h, struct net_bridge_fdb_entry, hlist);
 204                         if (f->dst != p)
 205                                 continue;
 206
 207                         if (f->is_static && !do_all)
 208                                 continue;
 209                         /*
 210                          * if multiple ports all have the same device address
 211                          * then when one port is deleted, assign
 212                          * the local entry to other port
 213                          */
 214                         if (f->is_local) {
 215                                 struct net_bridge_port *op;
 216                                 list_for_each_entry(op, &br->port_list, list) {
 217                                         if (op != p &&
 218                                             ether_addr_equal(op->dev->dev_addr,
 219                                                              f->addr.addr)) {
 220                                                 f->dst = op;
 221                                                 goto skip_delete;
 222                                         }
 223                                 }
 224                         }
 225
 226                         fdb_delete(br, f);
 227                 skip_delete: ;
 228                 }
 229         }
 230         spin_unlock_bh(&br->hash_lock);
 231 }
 232
 233 /* No locking or refcounting, assumes caller has rcu_read_lock */
 234 struct net_bridge_fdb_entry *__br_fdb_get(struct net_bridge *br,
 235                                           const unsigned char *addr,
 236                                           __u16 vid)
 237 {
 238         struct hlist_node *h;
 239         struct net_bridge_fdb_entry *fdb;
 240
 241         hlist_for_each_entry_rcu(fdb, h,
 242                                 &br->hash[br_mac_hash(addr, vid)], hlist) {
 243                 if (ether_addr_equal(fdb->addr.addr, addr) &&
 244                     fdb->vlan_id == vid) {
 245                         if (unlikely(has_expired(br, fdb)))
 246                                 break;
 247                         return fdb;
 248                 }
 249         }
 250
 251         return NULL;
 252 }
 253
 254 #if IS_ENABLED(CONFIG_ATM_LANE)
 255 /* Interface used by ATM LANE hook to test
 256  * if an addr is on some other bridge port */
 257 int br_fdb_test_addr(struct net_device *dev, unsigned char *addr)
 258 {
 259         struct net_bridge_fdb_entry *fdb;
 260         struct net_bridge_port *port;
 261         int ret;
 262
 263         rcu_read_lock();
 264         port = br_port_get_rcu(dev);
 265         if (!port)
 266                 ret = 0;
 267         else {
 268                 fdb = __br_fdb_get(port->br, addr, 0);
 269                 ret = fdb && fdb->dst && fdb->dst->dev != dev &&
 270                         fdb->dst->state == BR_STATE_FORWARDING;
 271         }
 272         rcu_read_unlock();
 273
 274         return ret;
 275 }
 276 #endif /* CONFIG_ATM_LANE */
 277
 278 /*
 279  * Fill buffer with forwarding table records in
 280  * the API format.
 281  */
 282 int br_fdb_fillbuf(struct net_bridge *br, void *buf,
 283                    unsigned long maxnum, unsigned long skip)
 284 {
 285         struct __fdb_entry *fe = buf;
 286         int i, num = 0;
 287         struct hlist_node *h;
 288         struct net_bridge_fdb_entry *f;
 289
 290         memset(buf, 0, maxnum*sizeof(struct __fdb_entry));
 291
 292         rcu_read_lock();
 293         for (i = 0; i < BR_HASH_SIZE; i++) {
 294                 hlist_for_each_entry_rcu(f, h, &br->hash[i], hlist) {
 295                         if (num >= maxnum)
 296                                 goto out;
 297
 298                         if (has_expired(br, f))
 299                                 continue;
 300
 301                         /* ignore pseudo entry for local MAC address */
 302                         if (!f->dst)
 303                                 continue;
 304
 305                         if (skip) {
 306                                 --skip;
 307                                 continue;
 308                         }
 309
 310                         /* convert from internal format to API */
 311                         memcpy(fe->mac_addr, f->addr.addr, ETH_ALEN);
 312
 313                         /* due to ABI compat need to split into hi/lo */
 314                         fe->port_no = f->dst->port_no;
 315                         fe->port_hi = f->dst->port_no >> 8;
 316
 317                         fe->is_local = f->is_local;
 318                         if (!f->is_static)
 319                                 fe->ageing_timer_value = jiffies_delta_to_clock_t(jiffies - f->updated);
 320                         ++fe;
 321                         ++num;
 322                 }
 323         }
 324
 325  out:
 326         rcu_read_unlock();
 327
 328         return num;
 329 }
 330
 331 static struct net_bridge_fdb_entry *fdb_find(struct hlist_head *head,
 332                                              const unsigned char *addr,
 333                                              __u16 vid)
 334 {
 335         struct hlist_node *h;
 336         struct net_bridge_fdb_entry *fdb;
 337
 338         hlist_for_each_entry(fdb, h, head, hlist) {
 339                 if (ether_addr_equal(fdb->addr.addr, addr) &&
 340                     fdb->vlan_id == vid)
 341                         return fdb;
 342         }
 343         return NULL;
 344 }
 345
 346 static struct net_bridge_fdb_entry *fdb_find_rcu(struct hlist_head *head,
 347                                                  const unsigned char *addr,
 348                                                  __u16 vid)
 349 {
 350         struct hlist_node *h;
 351         struct net_bridge_fdb_entry *fdb;
 352
 353         hlist_for_each_entry_rcu(fdb, h, head, hlist) {
 354                 if (ether_addr_equal(fdb->addr.addr, addr) &&
 355                     fdb->vlan_id == vid)
 356                         return fdb;
 357         }
 358         return NULL;
 359 }
 360
 361 static struct net_bridge_fdb_entry *fdb_create(struct hlist_head *head,
 362                                                struct net_bridge_port *source,
 363                                                const unsigned char *addr,
 364                                                __u16 vid)
 365 {
 366         struct net_bridge_fdb_entry *fdb;
 367
 368         fdb = kmem_cache_alloc(br_fdb_cache, GFP_ATOMIC);
 369         if (fdb) {
 370                 memcpy(fdb->addr.addr, addr, ETH_ALEN);
 371                 fdb->dst = source;
 372                 fdb->vlan_id = vid;
 373                 fdb->is_local = 0;
 374                 fdb->is_static = 0;
 375                 fdb->updated = fdb->used = jiffies;
 376                 hlist_add_head_rcu(&fdb->hlist, head);
 377         }
 378         return fdb;
 379 }
 380
 381 static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
 382                   const unsigned char *addr)
 383 {
 384         struct hlist_head *head = &br->hash[br_mac_hash(addr, 0)];
 385         struct net_bridge_fdb_entry *fdb;
 386
 387         if (!is_valid_ether_addr(addr))
 388                 return -EINVAL;
 389
 390         fdb = fdb_find(head, addr, 0);
 391         if (fdb) {
 392                 /* it is okay to have multiple ports with same
 393                  * address, just use the first one.
 394                  */
 395                 if (fdb->is_local)
 396                         return 0;
 397                 br_warn(br, "adding interface %s with same address "
 398                        "as a received packet\n",
 399                        source->dev->name);
 400                 fdb_delete(br, fdb);
 401         }
 402
 403         fdb = fdb_create(head, source, addr, 0);
 404         if (!fdb)
 405                 return -ENOMEM;
 406
 407         fdb->is_local = fdb->is_static = 1;
 408         fdb_notify(br, fdb, RTM_NEWNEIGH);
 409         return 0;
 410 }
 411
 412 /* Add entry for local address of interface */
 413 int br_fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
 414                   const unsigned char *addr)
 415 {
 416         int ret;
 417
 418         spin_lock_bh(&br->hash_lock);
 419         ret = fdb_insert(br, source, addr);
 420         spin_unlock_bh(&br->hash_lock);
 421         return ret;
 422 }
 423
 424 void br_fdb_update(struct net_bridge *br, struct net_bridge_port *source,
 425                    const unsigned char *addr, u16 vid)
 426 {
 427         struct hlist_head *head = &br->hash[br_mac_hash(addr, vid)];
 428         struct net_bridge_fdb_entry *fdb;
 429
 430         /* some users want to always flood. */
 431         if (hold_time(br) == 0)
 432                 return;
 433
 434         /* ignore packets unless we are using this port */
 435         if (!(source->state == BR_STATE_LEARNING ||
 436               source->state == BR_STATE_FORWARDING))
 437                 return;
 438
 439         fdb = fdb_find_rcu(head, addr, vid);
 440         if (likely(fdb)) {
 441                 /* attempt to update an entry for a local interface */
 442                 if (unlikely(fdb->is_local)) {
 443                         if (net_ratelimit())
 444                                 br_warn(br, "received packet on %s with "
 445                                         "own address as source address\n",
 446                                         source->dev->name);
 447                 } else {
 448                         /* fastpath: update of existing entry */
 449                         fdb->dst = source;
 450                         fdb->updated = jiffies;
 451                 }
 452         } else {
 453                 spin_lock(&br->hash_lock);
 454                 if (likely(!fdb_find(head, addr, vid))) {
 455                         fdb = fdb_create(head, source, addr, vid);
 456                         if (fdb)
 457                                 fdb_notify(br, fdb, RTM_NEWNEIGH);
 458                 }
 459                 /* else  we lose race and someone else inserts
 460                  * it first, don't bother updating
 461                  */
 462                 spin_unlock(&br->hash_lock);
 463         }
 464 }
 465
 466 static int fdb_to_nud(const struct net_bridge_fdb_entry *fdb)
 467 {
 468         if (fdb->is_local)
 469                 return NUD_PERMANENT;
 470         else if (fdb->is_static)
 471                 return NUD_NOARP;
 472         else if (has_expired(fdb->dst->br, fdb))
 473                 return NUD_STALE;
 474         else
 475                 return NUD_REACHABLE;
 476 }
 477
 478 static int fdb_fill_info(struct sk_buff *skb, const struct net_bridge *br,
 479                          const struct net_bridge_fdb_entry *fdb,
 480                          u32 portid, u32 seq, int type, unsigned int flags)
 481 {
 482         unsigned long now = jiffies;
 483         struct nda_cacheinfo ci;
 484         struct nlmsghdr *nlh;
 485         struct ndmsg *ndm;
 486
 487         nlh = nlmsg_put(skb, portid, seq, type, sizeof(*ndm), flags);
 488         if (nlh == NULL)
 489                 return -EMSGSIZE;
 490
 491         ndm = nlmsg_data(nlh);
 492         ndm->ndm_family  = AF_BRIDGE;
 493         ndm->ndm_pad1    = 0;
 494         ndm->ndm_pad2    = 0;
 495         ndm->ndm_flags   = 0;
 496         ndm->ndm_type    = 0;
 497         ndm->ndm_ifindex = fdb->dst ? fdb->dst->dev->ifindex : br->dev->ifindex;
 498         ndm->ndm_state   = fdb_to_nud(fdb);
 499
 500         if (nla_put(skb, NDA_LLADDR, ETH_ALEN, &fdb->addr))
 501                 goto nla_put_failure;
 502         ci.ndm_used      = jiffies_to_clock_t(now - fdb->used);
 503         ci.ndm_confirmed = 0;
 504         ci.ndm_updated   = jiffies_to_clock_t(now - fdb->updated);
 505         ci.ndm_refcnt    = 0;
 506         if (nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci))
 507                 goto nla_put_failure;
 508         return nlmsg_end(skb, nlh);
 509
 510 nla_put_failure:
 511         nlmsg_cancel(skb, nlh);
 512         return -EMSGSIZE;
 513 }
 514
 515 static inline size_t fdb_nlmsg_size(void)
 516 {
 517         return NLMSG_ALIGN(sizeof(struct ndmsg))
 518                 + nla_total_size(ETH_ALEN) /* NDA_LLADDR */
 519                 + nla_total_size(sizeof(struct nda_cacheinfo));
 520 }
 521
 522 static void fdb_notify(struct net_bridge *br,
 523                        const struct net_bridge_fdb_entry *fdb, int type)
 524 {
 525         struct net *net = dev_net(br->dev);
 526         struct sk_buff *skb;
 527         int err = -ENOBUFS;
 528
 529         skb = nlmsg_new(fdb_nlmsg_size(), GFP_ATOMIC);
 530         if (skb == NULL)
 531                 goto errout;
 532
 533         err = fdb_fill_info(skb, br, fdb, 0, 0, type, 0);
 534         if (err < 0) {
 535                 /* -EMSGSIZE implies BUG in fdb_nlmsg_size() */
 536                 WARN_ON(err == -EMSGSIZE);
 537                 kfree_skb(skb);
 538                 goto errout;
 539         }
 540         rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
 541         return;
 542 errout:
 543         if (err < 0)
 544                 rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
 545 }
 546
 547 /* Dump information about entries, in response to GETNEIGH */
 548 int br_fdb_dump(struct sk_buff *skb,
 549                 struct netlink_callback *cb,
 550                 struct net_device *dev,
 551                 int idx)
 552 {
 553         struct net_bridge *br = netdev_priv(dev);
 554         int i;
 555
 556         if (!(dev->priv_flags & IFF_EBRIDGE))
 557                 goto out;
 558
 559         for (i = 0; i < BR_HASH_SIZE; i++) {
 560                 struct hlist_node *h;
 561                 struct net_bridge_fdb_entry *f;
 562
 563                 hlist_for_each_entry_rcu(f, h, &br->hash[i], hlist) {
 564                         if (idx < cb->args[0])
 565                                 goto skip;
 566
 567                         if (fdb_fill_info(skb, br, f,
 568                                           NETLINK_CB(cb->skb).portid,
 569                                           cb->nlh->nlmsg_seq,
 570                                           RTM_NEWNEIGH,
 571                                           NLM_F_MULTI) < 0)
 572                                 break;
 573 skip:
 574                         ++idx;
 575                 }
 576         }
 577
 578 out:
 579         return idx;
 580 }
 581
 582 /* Update (create or replace) forwarding database entry */
 583 static int fdb_add_entry(struct net_bridge_port *source, const __u8 *addr,
 584                          __u16 state, __u16 flags, __u16 vid)
 585 {
 586         struct net_bridge *br = source->br;
 587         struct hlist_head *head = &br->hash[br_mac_hash(addr, vid)];
 588         struct net_bridge_fdb_entry *fdb;
 589
 590         fdb = fdb_find(head, addr, vid);
 591         if (fdb == NULL) {
 592                 if (!(flags & NLM_F_CREATE))
 593                         return -ENOENT;
 594
 595                 fdb = fdb_create(head, source, addr, vid);
 596                 if (!fdb)
 597                         return -ENOMEM;
 598                 fdb_notify(br, fdb, RTM_NEWNEIGH);
 599         } else {
 600                 if (flags & NLM_F_EXCL)
 601                         return -EEXIST;
 602         }
 603
 604         if (fdb_to_nud(fdb) != state) {
 605                 if (state & NUD_PERMANENT)
 606                         fdb->is_local = fdb->is_static = 1;
 607                 else if (state & NUD_NOARP) {
 608                         fdb->is_local = 0;
 609                         fdb->is_static = 1;
 610                 } else
 611                         fdb->is_local = fdb->is_static = 0;
 612
 613                 fdb->updated = fdb->used = jiffies;
 614                 fdb_notify(br, fdb, RTM_NEWNEIGH);
 615         }
 616
 617         return 0;
 618 }
 619
 620 /* Add new permanent fdb entry with RTM_NEWNEIGH */
 621 int br_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
 622                struct net_device *dev,
 623                const unsigned char *addr, u16 nlh_flags)
 624 {
 625         struct net_bridge_port *p;
 626         int err = 0;
 627
 628         if (!(ndm->ndm_state & (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE))) {
 629                 pr_info("bridge: RTM_NEWNEIGH with invalid state %#x\n", ndm->ndm_state);
 630                 return -EINVAL;
 631         }
 632
 633         p = br_port_get_rtnl(dev);
 634         if (p == NULL) {
 635                 pr_info("bridge: RTM_NEWNEIGH %s not a bridge port\n",
 636                         dev->name);
 637                 return -EINVAL;
 638         }
 639
 640         if (ndm->ndm_flags & NTF_USE) {
 641                 rcu_read_lock();
 642                 br_fdb_update(p->br, p, addr, 0);
 643                 rcu_read_unlock();
 644         } else {
 645                 spin_lock_bh(&p->br->hash_lock);
 646                 err = fdb_add_entry(p, addr, ndm->ndm_state, nlh_flags,
 647                                 0);
 648                 spin_unlock_bh(&p->br->hash_lock);
 649         }
 650
 651         return err;
 652 }
 653
 654 static int fdb_delete_by_addr(struct net_bridge_port *p, const u8 *addr)
 655 {
 656         struct net_bridge *br = p->br;
 657         struct hlist_head *head = &br->hash[br_mac_hash(addr, 0)];
 658         struct net_bridge_fdb_entry *fdb;
 659
 660         fdb = fdb_find(head, addr, 0);
 661         if (!fdb)
 662                 return -ENOENT;
 663
 664         fdb_delete(p->br, fdb);
 665         return 0;
 666 }
 667
 668 /* Remove neighbor entry with RTM_DELNEIGH */
 669 int br_fdb_delete(struct ndmsg *ndm, struct net_device *dev,
 670                   const unsigned char *addr)
 671 {
 672         struct net_bridge_port *p;
 673         int err;
 674
 675         p = br_port_get_rtnl(dev);
 676         if (p == NULL) {
 677                 pr_info("bridge: RTM_DELNEIGH %s not a bridge port\n",
 678                         dev->name);
 679                 return -EINVAL;
 680         }
 681
 682         spin_lock_bh(&p->br->hash_lock);
 683         err = fdb_delete_by_addr(p, addr);
 684         spin_unlock_bh(&p->br->hash_lock);
 685
 686         return err;
 687 }