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