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