net/bridge/br_fdb.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *      Forwarding database
   4  *      Linux ethernet bridge
   5  *
   6  *      Authors:
   7  *      Lennert Buytenhek               <buytenh@gnu.org>
   8  */
   9
  10 #include <linux/kernel.h>
  11 #include <linux/init.h>
  12 #include <linux/rculist.h>
  13 #include <linux/spinlock.h>
  14 #include <linux/times.h>
  15 #include <linux/netdevice.h>
  16 #include <linux/etherdevice.h>
  17 #include <linux/jhash.h>
  18 #include <linux/random.h>
  19 #include <linux/slab.h>
  20 #include <linux/atomic.h>
  21 #include <asm/unaligned.h>
  22 #include <linux/if_vlan.h>
  23 #include <net/switchdev.h>
  24 #include <trace/events/bridge.h>
  25 #include "br_private.h"
  26
  27 static const struct rhashtable_params br_fdb_rht_params = {
  28         .head_offset = offsetof(struct net_bridge_fdb_entry, rhnode),
  29         .key_offset = offsetof(struct net_bridge_fdb_entry, key),
  30         .key_len = sizeof(struct net_bridge_fdb_key),
  31         .automatic_shrinking = true,
  32 };
  33
  34 static struct kmem_cache *br_fdb_cache __read_mostly;
  35
  36 int __init br_fdb_init(void)
  37 {
  38         br_fdb_cache = KMEM_CACHE(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 void fdb_rcu_free(struct rcu_head *head)
  77 {
  78         struct net_bridge_fdb_entry *ent
  79                 = container_of(head, struct net_bridge_fdb_entry, rcu);
  80         kmem_cache_free(br_fdb_cache, ent);
  81 }
  82
  83 static int fdb_to_nud(const struct net_bridge *br,
  84                       const struct net_bridge_fdb_entry *fdb)
  85 {
  86         if (test_bit(BR_FDB_LOCAL, &fdb->flags))
  87                 return NUD_PERMANENT;
  88         else if (test_bit(BR_FDB_STATIC, &fdb->flags))
  89                 return NUD_NOARP;
  90         else if (has_expired(br, fdb))
  91                 return NUD_STALE;
  92         else
  93                 return NUD_REACHABLE;
  94 }
  95
  96 static int fdb_fill_info(struct sk_buff *skb, const struct net_bridge *br,
  97                          const struct net_bridge_fdb_entry *fdb,
  98                          u32 portid, u32 seq, int type, unsigned int flags)
  99 {
 100         const struct net_bridge_port *dst = READ_ONCE(fdb->dst);
 101         unsigned long now = jiffies;
 102         struct nda_cacheinfo ci;
 103         struct nlmsghdr *nlh;
 104         struct ndmsg *ndm;
 105         u32 ext_flags = 0;
 106
 107         nlh = nlmsg_put(skb, portid, seq, type, sizeof(*ndm), flags);
 108         if (nlh == NULL)
 109                 return -EMSGSIZE;
 110
 111         ndm = nlmsg_data(nlh);
 112         ndm->ndm_family  = AF_BRIDGE;
 113         ndm->ndm_pad1    = 0;
 114         ndm->ndm_pad2    = 0;
 115         ndm->ndm_flags   = 0;
 116         ndm->ndm_type    = 0;
 117         ndm->ndm_ifindex = dst ? dst->dev->ifindex : br->dev->ifindex;
 118         ndm->ndm_state   = fdb_to_nud(br, fdb);
 119
 120         if (test_bit(BR_FDB_OFFLOADED, &fdb->flags))
 121                 ndm->ndm_flags |= NTF_OFFLOADED;
 122         if (test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags))
 123                 ndm->ndm_flags |= NTF_EXT_LEARNED;
 124         if (test_bit(BR_FDB_STICKY, &fdb->flags))
 125                 ndm->ndm_flags |= NTF_STICKY;
 126         if (test_bit(BR_FDB_LOCKED, &fdb->flags))
 127                 ext_flags |= NTF_EXT_LOCKED;
 128
 129         if (nla_put(skb, NDA_LLADDR, ETH_ALEN, &fdb->key.addr))
 130                 goto nla_put_failure;
 131         if (nla_put_u32(skb, NDA_MASTER, br->dev->ifindex))
 132                 goto nla_put_failure;
 133         if (nla_put_u32(skb, NDA_FLAGS_EXT, ext_flags))
 134                 goto nla_put_failure;
 135
 136         ci.ndm_used      = jiffies_to_clock_t(now - fdb->used);
 137         ci.ndm_confirmed = 0;
 138         ci.ndm_updated   = jiffies_to_clock_t(now - fdb->updated);
 139         ci.ndm_refcnt    = 0;
 140         if (nla_put(skb, NDA_CACHEINFO, sizeof(ci), &ci))
 141                 goto nla_put_failure;
 142
 143         if (fdb->key.vlan_id && nla_put(skb, NDA_VLAN, sizeof(u16),
 144                                         &fdb->key.vlan_id))
 145                 goto nla_put_failure;
 146
 147         if (test_bit(BR_FDB_NOTIFY, &fdb->flags)) {
 148                 struct nlattr *nest = nla_nest_start(skb, NDA_FDB_EXT_ATTRS);
 149                 u8 notify_bits = FDB_NOTIFY_BIT;
 150
 151                 if (!nest)
 152                         goto nla_put_failure;
 153                 if (test_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags))
 154                         notify_bits |= FDB_NOTIFY_INACTIVE_BIT;
 155
 156                 if (nla_put_u8(skb, NFEA_ACTIVITY_NOTIFY, notify_bits)) {
 157                         nla_nest_cancel(skb, nest);
 158                         goto nla_put_failure;
 159                 }
 160
 161                 nla_nest_end(skb, nest);
 162         }
 163
 164         nlmsg_end(skb, nlh);
 165         return 0;
 166
 167 nla_put_failure:
 168         nlmsg_cancel(skb, nlh);
 169         return -EMSGSIZE;
 170 }
 171
 172 static inline size_t fdb_nlmsg_size(void)
 173 {
 174         return NLMSG_ALIGN(sizeof(struct ndmsg))
 175                 + nla_total_size(ETH_ALEN) /* NDA_LLADDR */
 176                 + nla_total_size(sizeof(u32)) /* NDA_MASTER */
 177                 + nla_total_size(sizeof(u32)) /* NDA_FLAGS_EXT */
 178                 + nla_total_size(sizeof(u16)) /* NDA_VLAN */
 179                 + nla_total_size(sizeof(struct nda_cacheinfo))
 180                 + nla_total_size(0) /* NDA_FDB_EXT_ATTRS */
 181                 + nla_total_size(sizeof(u8)); /* NFEA_ACTIVITY_NOTIFY */
 182 }
 183
 184 static void fdb_notify(struct net_bridge *br,
 185                        const struct net_bridge_fdb_entry *fdb, int type,
 186                        bool swdev_notify)
 187 {
 188         struct net *net = dev_net(br->dev);
 189         struct sk_buff *skb;
 190         int err = -ENOBUFS;
 191
 192         if (swdev_notify)
 193                 br_switchdev_fdb_notify(br, fdb, type);
 194
 195         skb = nlmsg_new(fdb_nlmsg_size(), GFP_ATOMIC);
 196         if (skb == NULL)
 197                 goto errout;
 198
 199         err = fdb_fill_info(skb, br, fdb, 0, 0, type, 0);
 200         if (err < 0) {
 201                 /* -EMSGSIZE implies BUG in fdb_nlmsg_size() */
 202                 WARN_ON(err == -EMSGSIZE);
 203                 kfree_skb(skb);
 204                 goto errout;
 205         }
 206         rtnl_notify(skb, net, 0, RTNLGRP_NEIGH, NULL, GFP_ATOMIC);
 207         return;
 208 errout:
 209         rtnl_set_sk_err(net, RTNLGRP_NEIGH, err);
 210 }
 211
 212 static struct net_bridge_fdb_entry *fdb_find_rcu(struct rhashtable *tbl,
 213                                                  const unsigned char *addr,
 214                                                  __u16 vid)
 215 {
 216         struct net_bridge_fdb_key key;
 217
 218         WARN_ON_ONCE(!rcu_read_lock_held());
 219
 220         key.vlan_id = vid;
 221         memcpy(key.addr.addr, addr, sizeof(key.addr.addr));
 222
 223         return rhashtable_lookup(tbl, &key, br_fdb_rht_params);
 224 }
 225
 226 /* requires bridge hash_lock */
 227 static struct net_bridge_fdb_entry *br_fdb_find(struct net_bridge *br,
 228                                                 const unsigned char *addr,
 229                                                 __u16 vid)
 230 {
 231         struct net_bridge_fdb_entry *fdb;
 232
 233         lockdep_assert_held_once(&br->hash_lock);
 234
 235         rcu_read_lock();
 236         fdb = fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
 237         rcu_read_unlock();
 238
 239         return fdb;
 240 }
 241
 242 struct net_device *br_fdb_find_port(const struct net_device *br_dev,
 243                                     const unsigned char *addr,
 244                                     __u16 vid)
 245 {
 246         struct net_bridge_fdb_entry *f;
 247         struct net_device *dev = NULL;
 248         struct net_bridge *br;
 249
 250         ASSERT_RTNL();
 251
 252         if (!netif_is_bridge_master(br_dev))
 253                 return NULL;
 254
 255         br = netdev_priv(br_dev);
 256         rcu_read_lock();
 257         f = br_fdb_find_rcu(br, addr, vid);
 258         if (f && f->dst)
 259                 dev = f->dst->dev;
 260         rcu_read_unlock();
 261
 262         return dev;
 263 }
 264 EXPORT_SYMBOL_GPL(br_fdb_find_port);
 265
 266 struct net_bridge_fdb_entry *br_fdb_find_rcu(struct net_bridge *br,
 267                                              const unsigned char *addr,
 268                                              __u16 vid)
 269 {
 270         return fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
 271 }
 272
 273 /* When a static FDB entry is added, the mac address from the entry is
 274  * added to the bridge private HW address list and all required ports
 275  * are then updated with the new information.
 276  * Called under RTNL.
 277  */
 278 static void fdb_add_hw_addr(struct net_bridge *br, const unsigned char *addr)
 279 {
 280         int err;
 281         struct net_bridge_port *p;
 282
 283         ASSERT_RTNL();
 284
 285         list_for_each_entry(p, &br->port_list, list) {
 286                 if (!br_promisc_port(p)) {
 287                         err = dev_uc_add(p->dev, addr);
 288                         if (err)
 289                                 goto undo;
 290                 }
 291         }
 292
 293         return;
 294 undo:
 295         list_for_each_entry_continue_reverse(p, &br->port_list, list) {
 296                 if (!br_promisc_port(p))
 297                         dev_uc_del(p->dev, addr);
 298         }
 299 }
 300
 301 /* When a static FDB entry is deleted, the HW address from that entry is
 302  * also removed from the bridge private HW address list and updates all
 303  * the ports with needed information.
 304  * Called under RTNL.
 305  */
 306 static void fdb_del_hw_addr(struct net_bridge *br, const unsigned char *addr)
 307 {
 308         struct net_bridge_port *p;
 309
 310         ASSERT_RTNL();
 311
 312         list_for_each_entry(p, &br->port_list, list) {
 313                 if (!br_promisc_port(p))
 314                         dev_uc_del(p->dev, addr);
 315         }
 316 }
 317
 318 static void fdb_delete(struct net_bridge *br, struct net_bridge_fdb_entry *f,
 319                        bool swdev_notify)
 320 {
 321         trace_fdb_delete(br, f);
 322
 323         if (test_bit(BR_FDB_STATIC, &f->flags))
 324                 fdb_del_hw_addr(br, f->key.addr.addr);
 325
 326         hlist_del_init_rcu(&f->fdb_node);
 327         rhashtable_remove_fast(&br->fdb_hash_tbl, &f->rhnode,
 328                                br_fdb_rht_params);
 329         if (test_and_clear_bit(BR_FDB_DYNAMIC_LEARNED, &f->flags))
 330                 atomic_dec(&br->fdb_n_learned);
 331         fdb_notify(br, f, RTM_DELNEIGH, swdev_notify);
 332         call_rcu(&f->rcu, fdb_rcu_free);
 333 }
 334
 335 /* Delete a local entry if no other port had the same address.
 336  *
 337  * This function should only be called on entries with BR_FDB_LOCAL set,
 338  * so even with BR_FDB_ADDED_BY_USER cleared we never need to increase
 339  * the accounting for dynamically learned entries again.
 340  */
 341 static void fdb_delete_local(struct net_bridge *br,
 342                              const struct net_bridge_port *p,
 343                              struct net_bridge_fdb_entry *f)
 344 {
 345         const unsigned char *addr = f->key.addr.addr;
 346         struct net_bridge_vlan_group *vg;
 347         const struct net_bridge_vlan *v;
 348         struct net_bridge_port *op;
 349         u16 vid = f->key.vlan_id;
 350
 351         /* Maybe another port has same hw addr? */
 352         list_for_each_entry(op, &br->port_list, list) {
 353                 vg = nbp_vlan_group(op);
 354                 if (op != p && ether_addr_equal(op->dev->dev_addr, addr) &&
 355                     (!vid || br_vlan_find(vg, vid))) {
 356                         f->dst = op;
 357                         clear_bit(BR_FDB_ADDED_BY_USER, &f->flags);
 358                         return;
 359                 }
 360         }
 361
 362         vg = br_vlan_group(br);
 363         v = br_vlan_find(vg, vid);
 364         /* Maybe bridge device has same hw addr? */
 365         if (p && ether_addr_equal(br->dev->dev_addr, addr) &&
 366             (!vid || (v && br_vlan_should_use(v)))) {
 367                 f->dst = NULL;
 368                 clear_bit(BR_FDB_ADDED_BY_USER, &f->flags);
 369                 return;
 370         }
 371
 372         fdb_delete(br, f, true);
 373 }
 374
 375 void br_fdb_find_delete_local(struct net_bridge *br,
 376                               const struct net_bridge_port *p,
 377                               const unsigned char *addr, u16 vid)
 378 {
 379         struct net_bridge_fdb_entry *f;
 380
 381         spin_lock_bh(&br->hash_lock);
 382         f = br_fdb_find(br, addr, vid);
 383         if (f && test_bit(BR_FDB_LOCAL, &f->flags) &&
 384             !test_bit(BR_FDB_ADDED_BY_USER, &f->flags) && f->dst == p)
 385                 fdb_delete_local(br, p, f);
 386         spin_unlock_bh(&br->hash_lock);
 387 }
 388
 389 static struct net_bridge_fdb_entry *fdb_create(struct net_bridge *br,
 390                                                struct net_bridge_port *source,
 391                                                const unsigned char *addr,
 392                                                __u16 vid,
 393                                                unsigned long flags)
 394 {
 395         bool learned = !test_bit(BR_FDB_ADDED_BY_USER, &flags) &&
 396                        !test_bit(BR_FDB_LOCAL, &flags);
 397         u32 max_learned = READ_ONCE(br->fdb_max_learned);
 398         struct net_bridge_fdb_entry *fdb;
 399         int err;
 400
 401         if (likely(learned)) {
 402                 int n_learned = atomic_read(&br->fdb_n_learned);
 403
 404                 if (unlikely(max_learned && n_learned >= max_learned))
 405                         return NULL;
 406                 __set_bit(BR_FDB_DYNAMIC_LEARNED, &flags);
 407         }
 408
 409         fdb = kmem_cache_alloc(br_fdb_cache, GFP_ATOMIC);
 410         if (!fdb)
 411                 return NULL;
 412
 413         memcpy(fdb->key.addr.addr, addr, ETH_ALEN);
 414         WRITE_ONCE(fdb->dst, source);
 415         fdb->key.vlan_id = vid;
 416         fdb->flags = flags;
 417         fdb->updated = fdb->used = jiffies;
 418         err = rhashtable_lookup_insert_fast(&br->fdb_hash_tbl, &fdb->rhnode,
 419                                             br_fdb_rht_params);
 420         if (err) {
 421                 kmem_cache_free(br_fdb_cache, fdb);
 422                 return NULL;
 423         }
 424
 425         if (likely(learned))
 426                 atomic_inc(&br->fdb_n_learned);
 427
 428         hlist_add_head_rcu(&fdb->fdb_node, &br->fdb_list);
 429
 430         return fdb;
 431 }
 432
 433 static int fdb_add_local(struct net_bridge *br, struct net_bridge_port *source,
 434                          const unsigned char *addr, u16 vid)
 435 {
 436         struct net_bridge_fdb_entry *fdb;
 437
 438         if (!is_valid_ether_addr(addr))
 439                 return -EINVAL;
 440
 441         fdb = br_fdb_find(br, addr, vid);
 442         if (fdb) {
 443                 /* it is okay to have multiple ports with same
 444                  * address, just use the first one.
 445                  */
 446                 if (test_bit(BR_FDB_LOCAL, &fdb->flags))
 447                         return 0;
 448                 br_warn(br, "adding interface %s with same address as a received packet (addr:%pM, vlan:%u)\n",
 449                         source ? source->dev->name : br->dev->name, addr, vid);
 450                 fdb_delete(br, fdb, true);
 451         }
 452
 453         fdb = fdb_create(br, source, addr, vid,
 454                          BIT(BR_FDB_LOCAL) | BIT(BR_FDB_STATIC));
 455         if (!fdb)
 456                 return -ENOMEM;
 457
 458         fdb_add_hw_addr(br, addr);
 459         fdb_notify(br, fdb, RTM_NEWNEIGH, true);
 460         return 0;
 461 }
 462
 463 void br_fdb_changeaddr(struct net_bridge_port *p, const unsigned char *newaddr)
 464 {
 465         struct net_bridge_vlan_group *vg;
 466         struct net_bridge_fdb_entry *f;
 467         struct net_bridge *br = p->br;
 468         struct net_bridge_vlan *v;
 469
 470         spin_lock_bh(&br->hash_lock);
 471         vg = nbp_vlan_group(p);
 472         hlist_for_each_entry(f, &br->fdb_list, fdb_node) {
 473                 if (f->dst == p && test_bit(BR_FDB_LOCAL, &f->flags) &&
 474                     !test_bit(BR_FDB_ADDED_BY_USER, &f->flags)) {
 475                         /* delete old one */
 476                         fdb_delete_local(br, p, f);
 477
 478                         /* if this port has no vlan information
 479                          * configured, we can safely be done at
 480                          * this point.
 481                          */
 482                         if (!vg || !vg->num_vlans)
 483                                 goto insert;
 484                 }
 485         }
 486
 487 insert:
 488         /* insert new address,  may fail if invalid address or dup. */
 489         fdb_add_local(br, p, newaddr, 0);
 490
 491         if (!vg || !vg->num_vlans)
 492                 goto done;
 493
 494         /* Now add entries for every VLAN configured on the port.
 495          * This function runs under RTNL so the bitmap will not change
 496          * from under us.
 497          */
 498         list_for_each_entry(v, &vg->vlan_list, vlist)
 499                 fdb_add_local(br, p, newaddr, v->vid);
 500
 501 done:
 502         spin_unlock_bh(&br->hash_lock);
 503 }
 504
 505 void br_fdb_change_mac_address(struct net_bridge *br, const u8 *newaddr)
 506 {
 507         struct net_bridge_vlan_group *vg;
 508         struct net_bridge_fdb_entry *f;
 509         struct net_bridge_vlan *v;
 510
 511         spin_lock_bh(&br->hash_lock);
 512
 513         /* If old entry was unassociated with any port, then delete it. */
 514         f = br_fdb_find(br, br->dev->dev_addr, 0);
 515         if (f && test_bit(BR_FDB_LOCAL, &f->flags) &&
 516             !f->dst && !test_bit(BR_FDB_ADDED_BY_USER, &f->flags))
 517                 fdb_delete_local(br, NULL, f);
 518
 519         fdb_add_local(br, NULL, newaddr, 0);
 520         vg = br_vlan_group(br);
 521         if (!vg || !vg->num_vlans)
 522                 goto out;
 523         /* Now remove and add entries for every VLAN configured on the
 524          * bridge.  This function runs under RTNL so the bitmap will not
 525          * change from under us.
 526          */
 527         list_for_each_entry(v, &vg->vlan_list, vlist) {
 528                 if (!br_vlan_should_use(v))
 529                         continue;
 530                 f = br_fdb_find(br, br->dev->dev_addr, v->vid);
 531                 if (f && test_bit(BR_FDB_LOCAL, &f->flags) &&
 532                     !f->dst && !test_bit(BR_FDB_ADDED_BY_USER, &f->flags))
 533                         fdb_delete_local(br, NULL, f);
 534                 fdb_add_local(br, NULL, newaddr, v->vid);
 535         }
 536 out:
 537         spin_unlock_bh(&br->hash_lock);
 538 }
 539
 540 void br_fdb_cleanup(struct work_struct *work)
 541 {
 542         struct net_bridge *br = container_of(work, struct net_bridge,
 543                                              gc_work.work);
 544         struct net_bridge_fdb_entry *f = NULL;
 545         unsigned long delay = hold_time(br);
 546         unsigned long work_delay = delay;
 547         unsigned long now = jiffies;
 548
 549         /* this part is tricky, in order to avoid blocking learning and
 550          * consequently forwarding, we rely on rcu to delete objects with
 551          * delayed freeing allowing us to continue traversing
 552          */
 553         rcu_read_lock();
 554         hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
 555                 unsigned long this_timer = f->updated + delay;
 556
 557                 if (test_bit(BR_FDB_STATIC, &f->flags) ||
 558                     test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &f->flags)) {
 559                         if (test_bit(BR_FDB_NOTIFY, &f->flags)) {
 560                                 if (time_after(this_timer, now))
 561                                         work_delay = min(work_delay,
 562                                                          this_timer - now);
 563                                 else if (!test_and_set_bit(BR_FDB_NOTIFY_INACTIVE,
 564                                                            &f->flags))
 565                                         fdb_notify(br, f, RTM_NEWNEIGH, false);
 566                         }
 567                         continue;
 568                 }
 569
 570                 if (time_after(this_timer, now)) {
 571                         work_delay = min(work_delay, this_timer - now);
 572                 } else {
 573                         spin_lock_bh(&br->hash_lock);
 574                         if (!hlist_unhashed(&f->fdb_node))
 575                                 fdb_delete(br, f, true);
 576                         spin_unlock_bh(&br->hash_lock);
 577                 }
 578         }
 579         rcu_read_unlock();
 580
 581         /* Cleanup minimum 10 milliseconds apart */
 582         work_delay = max_t(unsigned long, work_delay, msecs_to_jiffies(10));
 583         mod_delayed_work(system_long_wq, &br->gc_work, work_delay);
 584 }
 585
 586 static bool __fdb_flush_matches(const struct net_bridge *br,
 587                                 const struct net_bridge_fdb_entry *f,
 588                                 const struct net_bridge_fdb_flush_desc *desc)
 589 {
 590         const struct net_bridge_port *dst = READ_ONCE(f->dst);
 591         int port_ifidx = dst ? dst->dev->ifindex : br->dev->ifindex;
 592
 593         if (desc->vlan_id && desc->vlan_id != f->key.vlan_id)
 594                 return false;
 595         if (desc->port_ifindex && desc->port_ifindex != port_ifidx)
 596                 return false;
 597         if (desc->flags_mask && (f->flags & desc->flags_mask) != desc->flags)
 598                 return false;
 599
 600         return true;
 601 }
 602
 603 /* Flush forwarding database entries matching the description */
 604 void br_fdb_flush(struct net_bridge *br,
 605                   const struct net_bridge_fdb_flush_desc *desc)
 606 {
 607         struct net_bridge_fdb_entry *f;
 608
 609         rcu_read_lock();
 610         hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
 611                 if (!__fdb_flush_matches(br, f, desc))
 612                         continue;
 613
 614                 spin_lock_bh(&br->hash_lock);
 615                 if (!hlist_unhashed(&f->fdb_node))
 616                         fdb_delete(br, f, true);
 617                 spin_unlock_bh(&br->hash_lock);
 618         }
 619         rcu_read_unlock();
 620 }
 621
 622 static unsigned long __ndm_state_to_fdb_flags(u16 ndm_state)
 623 {
 624         unsigned long flags = 0;
 625
 626         if (ndm_state & NUD_PERMANENT)
 627                 __set_bit(BR_FDB_LOCAL, &flags);
 628         if (ndm_state & NUD_NOARP)
 629                 __set_bit(BR_FDB_STATIC, &flags);
 630
 631         return flags;
 632 }
 633
 634 static unsigned long __ndm_flags_to_fdb_flags(u8 ndm_flags)
 635 {
 636         unsigned long flags = 0;
 637
 638         if (ndm_flags & NTF_USE)
 639                 __set_bit(BR_FDB_ADDED_BY_USER, &flags);
 640         if (ndm_flags & NTF_EXT_LEARNED)
 641                 __set_bit(BR_FDB_ADDED_BY_EXT_LEARN, &flags);
 642         if (ndm_flags & NTF_OFFLOADED)
 643                 __set_bit(BR_FDB_OFFLOADED, &flags);
 644         if (ndm_flags & NTF_STICKY)
 645                 __set_bit(BR_FDB_STICKY, &flags);
 646
 647         return flags;
 648 }
 649
 650 static int __fdb_flush_validate_ifindex(const struct net_bridge *br,
 651                                         int ifindex,
 652                                         struct netlink_ext_ack *extack)
 653 {
 654         const struct net_device *dev;
 655
 656         dev = __dev_get_by_index(dev_net(br->dev), ifindex);
 657         if (!dev) {
 658                 NL_SET_ERR_MSG_MOD(extack, "Unknown flush device ifindex");
 659                 return -ENODEV;
 660         }
 661         if (!netif_is_bridge_master(dev) && !netif_is_bridge_port(dev)) {
 662                 NL_SET_ERR_MSG_MOD(extack, "Flush device is not a bridge or bridge port");
 663                 return -EINVAL;
 664         }
 665         if (netif_is_bridge_master(dev) && dev != br->dev) {
 666                 NL_SET_ERR_MSG_MOD(extack,
 667                                    "Flush bridge device does not match target bridge device");
 668                 return -EINVAL;
 669         }
 670         if (netif_is_bridge_port(dev)) {
 671                 struct net_bridge_port *p = br_port_get_rtnl(dev);
 672
 673                 if (p->br != br) {
 674                         NL_SET_ERR_MSG_MOD(extack, "Port belongs to a different bridge device");
 675                         return -EINVAL;
 676                 }
 677         }
 678
 679         return 0;
 680 }
 681
 682 static const struct nla_policy br_fdb_del_bulk_policy[NDA_MAX + 1] = {
 683         [NDA_VLAN]      = NLA_POLICY_RANGE(NLA_U16, 1, VLAN_N_VID - 2),
 684         [NDA_IFINDEX]   = NLA_POLICY_MIN(NLA_S32, 1),
 685         [NDA_NDM_STATE_MASK]    = { .type = NLA_U16 },
 686         [NDA_NDM_FLAGS_MASK]    = { .type = NLA_U8 },
 687 };
 688
 689 int br_fdb_delete_bulk(struct nlmsghdr *nlh, struct net_device *dev,
 690                        struct netlink_ext_ack *extack)
 691 {
 692         struct net_bridge_fdb_flush_desc desc = {};
 693         struct ndmsg *ndm = nlmsg_data(nlh);
 694         struct net_bridge_port *p = NULL;
 695         struct nlattr *tb[NDA_MAX + 1];
 696         struct net_bridge *br;
 697         u8 ndm_flags;
 698         int err;
 699
 700         ndm_flags = ndm->ndm_flags & ~FDB_FLUSH_IGNORED_NDM_FLAGS;
 701
 702         err = nlmsg_parse(nlh, sizeof(*ndm), tb, NDA_MAX,
 703                           br_fdb_del_bulk_policy, extack);
 704         if (err)
 705                 return err;
 706
 707         if (netif_is_bridge_master(dev)) {
 708                 br = netdev_priv(dev);
 709         } else {
 710                 p = br_port_get_rtnl(dev);
 711                 if (!p) {
 712                         NL_SET_ERR_MSG_MOD(extack, "Device is not a bridge port");
 713                         return -EINVAL;
 714                 }
 715                 br = p->br;
 716         }
 717
 718         if (tb[NDA_VLAN])
 719                 desc.vlan_id = nla_get_u16(tb[NDA_VLAN]);
 720
 721         if (ndm_flags & ~FDB_FLUSH_ALLOWED_NDM_FLAGS) {
 722                 NL_SET_ERR_MSG(extack, "Unsupported fdb flush ndm flag bits set");
 723                 return -EINVAL;
 724         }
 725         if (ndm->ndm_state & ~FDB_FLUSH_ALLOWED_NDM_STATES) {
 726                 NL_SET_ERR_MSG(extack, "Unsupported fdb flush ndm state bits set");
 727                 return -EINVAL;
 728         }
 729
 730         desc.flags |= __ndm_state_to_fdb_flags(ndm->ndm_state);
 731         desc.flags |= __ndm_flags_to_fdb_flags(ndm_flags);
 732         if (tb[NDA_NDM_STATE_MASK]) {
 733                 u16 ndm_state_mask = nla_get_u16(tb[NDA_NDM_STATE_MASK]);
 734
 735                 desc.flags_mask |= __ndm_state_to_fdb_flags(ndm_state_mask);
 736         }
 737         if (tb[NDA_NDM_FLAGS_MASK]) {
 738                 u8 ndm_flags_mask = nla_get_u8(tb[NDA_NDM_FLAGS_MASK]);
 739
 740                 desc.flags_mask |= __ndm_flags_to_fdb_flags(ndm_flags_mask);
 741         }
 742         if (tb[NDA_IFINDEX]) {
 743                 int ifidx = nla_get_s32(tb[NDA_IFINDEX]);
 744
 745                 err = __fdb_flush_validate_ifindex(br, ifidx, extack);
 746                 if (err)
 747                         return err;
 748                 desc.port_ifindex = ifidx;
 749         } else if (p) {
 750                 /* flush was invoked with port device and NTF_MASTER */
 751                 desc.port_ifindex = p->dev->ifindex;
 752         }
 753
 754         br_debug(br, "flushing port ifindex: %d vlan id: %u flags: 0x%lx flags mask: 0x%lx\n",
 755                  desc.port_ifindex, desc.vlan_id, desc.flags, desc.flags_mask);
 756
 757         br_fdb_flush(br, &desc);
 758
 759         return 0;
 760 }
 761
 762 /* Flush all entries referring to a specific port.
 763  * if do_all is set also flush static entries
 764  * if vid is set delete all entries that match the vlan_id
 765  */
 766 void br_fdb_delete_by_port(struct net_bridge *br,
 767                            const struct net_bridge_port *p,
 768                            u16 vid,
 769                            int do_all)
 770 {
 771         struct net_bridge_fdb_entry *f;
 772         struct hlist_node *tmp;
 773
 774         spin_lock_bh(&br->hash_lock);
 775         hlist_for_each_entry_safe(f, tmp, &br->fdb_list, fdb_node) {
 776                 if (f->dst != p)
 777                         continue;
 778
 779                 if (!do_all)
 780                         if (test_bit(BR_FDB_STATIC, &f->flags) ||
 781                             (test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &f->flags) &&
 782                              !test_bit(BR_FDB_OFFLOADED, &f->flags)) ||
 783                             (vid && f->key.vlan_id != vid))
 784                                 continue;
 785
 786                 if (test_bit(BR_FDB_LOCAL, &f->flags))
 787                         fdb_delete_local(br, p, f);
 788                 else
 789                         fdb_delete(br, f, true);
 790         }
 791         spin_unlock_bh(&br->hash_lock);
 792 }
 793
 794 #if IS_ENABLED(CONFIG_ATM_LANE)
 795 /* Interface used by ATM LANE hook to test
 796  * if an addr is on some other bridge port */
 797 int br_fdb_test_addr(struct net_device *dev, unsigned char *addr)
 798 {
 799         struct net_bridge_fdb_entry *fdb;
 800         struct net_bridge_port *port;
 801         int ret;
 802
 803         rcu_read_lock();
 804         port = br_port_get_rcu(dev);
 805         if (!port)
 806                 ret = 0;
 807         else {
 808                 const struct net_bridge_port *dst = NULL;
 809
 810                 fdb = br_fdb_find_rcu(port->br, addr, 0);
 811                 if (fdb)
 812                         dst = READ_ONCE(fdb->dst);
 813
 814                 ret = dst && dst->dev != dev &&
 815                       dst->state == BR_STATE_FORWARDING;
 816         }
 817         rcu_read_unlock();
 818
 819         return ret;
 820 }
 821 #endif /* CONFIG_ATM_LANE */
 822
 823 /*
 824  * Fill buffer with forwarding table records in
 825  * the API format.
 826  */
 827 int br_fdb_fillbuf(struct net_bridge *br, void *buf,
 828                    unsigned long maxnum, unsigned long skip)
 829 {
 830         struct net_bridge_fdb_entry *f;
 831         struct __fdb_entry *fe = buf;
 832         int num = 0;
 833
 834         memset(buf, 0, maxnum*sizeof(struct __fdb_entry));
 835
 836         rcu_read_lock();
 837         hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
 838                 if (num >= maxnum)
 839                         break;
 840
 841                 if (has_expired(br, f))
 842                         continue;
 843
 844                 /* ignore pseudo entry for local MAC address */
 845                 if (!f->dst)
 846                         continue;
 847
 848                 if (skip) {
 849                         --skip;
 850                         continue;
 851                 }
 852
 853                 /* convert from internal format to API */
 854                 memcpy(fe->mac_addr, f->key.addr.addr, ETH_ALEN);
 855
 856                 /* due to ABI compat need to split into hi/lo */
 857                 fe->port_no = f->dst->port_no;
 858                 fe->port_hi = f->dst->port_no >> 8;
 859
 860                 fe->is_local = test_bit(BR_FDB_LOCAL, &f->flags);
 861                 if (!test_bit(BR_FDB_STATIC, &f->flags))
 862                         fe->ageing_timer_value = jiffies_delta_to_clock_t(jiffies - f->updated);
 863                 ++fe;
 864                 ++num;
 865         }
 866         rcu_read_unlock();
 867
 868         return num;
 869 }
 870
 871 /* Add entry for local address of interface */
 872 int br_fdb_add_local(struct net_bridge *br, struct net_bridge_port *source,
 873                      const unsigned char *addr, u16 vid)
 874 {
 875         int ret;
 876
 877         spin_lock_bh(&br->hash_lock);
 878         ret = fdb_add_local(br, source, addr, vid);
 879         spin_unlock_bh(&br->hash_lock);
 880         return ret;
 881 }
 882
 883 /* returns true if the fdb was modified */
 884 static bool __fdb_mark_active(struct net_bridge_fdb_entry *fdb)
 885 {
 886         return !!(test_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags) &&
 887                   test_and_clear_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags));
 888 }
 889
 890 void br_fdb_update(struct net_bridge *br, struct net_bridge_port *source,
 891                    const unsigned char *addr, u16 vid, unsigned long flags)
 892 {
 893         struct net_bridge_fdb_entry *fdb;
 894
 895         /* some users want to always flood. */
 896         if (hold_time(br) == 0)
 897                 return;
 898
 899         fdb = fdb_find_rcu(&br->fdb_hash_tbl, addr, vid);
 900         if (likely(fdb)) {
 901                 /* attempt to update an entry for a local interface */
 902                 if (unlikely(test_bit(BR_FDB_LOCAL, &fdb->flags))) {
 903                         if (net_ratelimit())
 904                                 br_warn(br, "received packet on %s with own address as source address (addr:%pM, vlan:%u)\n",
 905                                         source->dev->name, addr, vid);
 906                 } else {
 907                         unsigned long now = jiffies;
 908                         bool fdb_modified = false;
 909
 910                         if (now != fdb->updated) {
 911                                 fdb->updated = now;
 912                                 fdb_modified = __fdb_mark_active(fdb);
 913                         }
 914
 915                         /* fastpath: update of existing entry */
 916                         if (unlikely(source != READ_ONCE(fdb->dst) &&
 917                                      !test_bit(BR_FDB_STICKY, &fdb->flags))) {
 918                                 br_switchdev_fdb_notify(br, fdb, RTM_DELNEIGH);
 919                                 WRITE_ONCE(fdb->dst, source);
 920                                 fdb_modified = true;
 921                                 /* Take over HW learned entry */
 922                                 if (unlikely(test_bit(BR_FDB_ADDED_BY_EXT_LEARN,
 923                                                       &fdb->flags)))
 924                                         clear_bit(BR_FDB_ADDED_BY_EXT_LEARN,
 925                                                   &fdb->flags);
 926                                 /* Clear locked flag when roaming to an
 927                                  * unlocked port.
 928                                  */
 929                                 if (unlikely(test_bit(BR_FDB_LOCKED, &fdb->flags)))
 930                                         clear_bit(BR_FDB_LOCKED, &fdb->flags);
 931                         }
 932
 933                         if (unlikely(test_bit(BR_FDB_ADDED_BY_USER, &flags))) {
 934                                 set_bit(BR_FDB_ADDED_BY_USER, &fdb->flags);
 935                                 if (test_and_clear_bit(BR_FDB_DYNAMIC_LEARNED,
 936                                                        &fdb->flags))
 937                                         atomic_dec(&br->fdb_n_learned);
 938                         }
 939                         if (unlikely(fdb_modified)) {
 940                                 trace_br_fdb_update(br, source, addr, vid, flags);
 941                                 fdb_notify(br, fdb, RTM_NEWNEIGH, true);
 942                         }
 943                 }
 944         } else {
 945                 spin_lock(&br->hash_lock);
 946                 fdb = fdb_create(br, source, addr, vid, flags);
 947                 if (fdb) {
 948                         trace_br_fdb_update(br, source, addr, vid, flags);
 949                         fdb_notify(br, fdb, RTM_NEWNEIGH, true);
 950                 }
 951                 /* else  we lose race and someone else inserts
 952                  * it first, don't bother updating
 953                  */
 954                 spin_unlock(&br->hash_lock);
 955         }
 956 }
 957
 958 /* Dump information about entries, in response to GETNEIGH */
 959 int br_fdb_dump(struct sk_buff *skb,
 960                 struct netlink_callback *cb,
 961                 struct net_device *dev,
 962                 struct net_device *filter_dev,
 963                 int *idx)
 964 {
 965         struct net_bridge *br = netdev_priv(dev);
 966         struct net_bridge_fdb_entry *f;
 967         int err = 0;
 968
 969         if (!netif_is_bridge_master(dev))
 970                 return err;
 971
 972         if (!filter_dev) {
 973                 err = ndo_dflt_fdb_dump(skb, cb, dev, NULL, idx);
 974                 if (err < 0)
 975                         return err;
 976         }
 977
 978         rcu_read_lock();
 979         hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
 980                 if (*idx < cb->args[2])
 981                         goto skip;
 982                 if (filter_dev && (!f->dst || f->dst->dev != filter_dev)) {
 983                         if (filter_dev != dev)
 984                                 goto skip;
 985                         /* !f->dst is a special case for bridge
 986                          * It means the MAC belongs to the bridge
 987                          * Therefore need a little more filtering
 988                          * we only want to dump the !f->dst case
 989                          */
 990                         if (f->dst)
 991                                 goto skip;
 992                 }
 993                 if (!filter_dev && f->dst)
 994                         goto skip;
 995
 996                 err = fdb_fill_info(skb, br, f,
 997                                     NETLINK_CB(cb->skb).portid,
 998                                     cb->nlh->nlmsg_seq,
 999                                     RTM_NEWNEIGH,
1000                                     NLM_F_MULTI);
1001                 if (err < 0)
1002                         break;
1003 skip:
1004                 *idx += 1;
1005         }
1006         rcu_read_unlock();
1007
1008         return err;
1009 }
1010
1011 int br_fdb_get(struct sk_buff *skb,
1012                struct nlattr *tb[],
1013                struct net_device *dev,
1014                const unsigned char *addr,
1015                u16 vid, u32 portid, u32 seq,
1016                struct netlink_ext_ack *extack)
1017 {
1018         struct net_bridge *br = netdev_priv(dev);
1019         struct net_bridge_fdb_entry *f;
1020         int err = 0;
1021
1022         rcu_read_lock();
1023         f = br_fdb_find_rcu(br, addr, vid);
1024         if (!f) {
1025                 NL_SET_ERR_MSG(extack, "Fdb entry not found");
1026                 err = -ENOENT;
1027                 goto errout;
1028         }
1029
1030         err = fdb_fill_info(skb, br, f, portid, seq,
1031                             RTM_NEWNEIGH, 0);
1032 errout:
1033         rcu_read_unlock();
1034         return err;
1035 }
1036
1037 /* returns true if the fdb is modified */
1038 static bool fdb_handle_notify(struct net_bridge_fdb_entry *fdb, u8 notify)
1039 {
1040         bool modified = false;
1041
1042         /* allow to mark an entry as inactive, usually done on creation */
1043         if ((notify & FDB_NOTIFY_INACTIVE_BIT) &&
1044             !test_and_set_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags))
1045                 modified = true;
1046
1047         if ((notify & FDB_NOTIFY_BIT) &&
1048             !test_and_set_bit(BR_FDB_NOTIFY, &fdb->flags)) {
1049                 /* enabled activity tracking */
1050                 modified = true;
1051         } else if (!(notify & FDB_NOTIFY_BIT) &&
1052                    test_and_clear_bit(BR_FDB_NOTIFY, &fdb->flags)) {
1053                 /* disabled activity tracking, clear notify state */
1054                 clear_bit(BR_FDB_NOTIFY_INACTIVE, &fdb->flags);
1055                 modified = true;
1056         }
1057
1058         return modified;
1059 }
1060
1061 /* Update (create or replace) forwarding database entry */
1062 static int fdb_add_entry(struct net_bridge *br, struct net_bridge_port *source,
1063                          const u8 *addr, struct ndmsg *ndm, u16 flags, u16 vid,
1064                          struct nlattr *nfea_tb[])
1065 {
1066         bool is_sticky = !!(ndm->ndm_flags & NTF_STICKY);
1067         bool refresh = !nfea_tb[NFEA_DONT_REFRESH];
1068         struct net_bridge_fdb_entry *fdb;
1069         u16 state = ndm->ndm_state;
1070         bool modified = false;
1071         u8 notify = 0;
1072
1073         /* If the port cannot learn allow only local and static entries */
1074         if (source && !(state & NUD_PERMANENT) && !(state & NUD_NOARP) &&
1075             !(source->state == BR_STATE_LEARNING ||
1076               source->state == BR_STATE_FORWARDING))
1077                 return -EPERM;
1078
1079         if (!source && !(state & NUD_PERMANENT)) {
1080                 pr_info("bridge: RTM_NEWNEIGH %s without NUD_PERMANENT\n",
1081                         br->dev->name);
1082                 return -EINVAL;
1083         }
1084
1085         if (is_sticky && (state & NUD_PERMANENT))
1086                 return -EINVAL;
1087
1088         if (nfea_tb[NFEA_ACTIVITY_NOTIFY]) {
1089                 notify = nla_get_u8(nfea_tb[NFEA_ACTIVITY_NOTIFY]);
1090                 if ((notify & ~BR_FDB_NOTIFY_SETTABLE_BITS) ||
1091                     (notify & BR_FDB_NOTIFY_SETTABLE_BITS) == FDB_NOTIFY_INACTIVE_BIT)
1092                         return -EINVAL;
1093         }
1094
1095         fdb = br_fdb_find(br, addr, vid);
1096         if (fdb == NULL) {
1097                 if (!(flags & NLM_F_CREATE))
1098                         return -ENOENT;
1099
1100                 fdb = fdb_create(br, source, addr, vid,
1101                                  BIT(BR_FDB_ADDED_BY_USER));
1102                 if (!fdb)
1103                         return -ENOMEM;
1104
1105                 modified = true;
1106         } else {
1107                 if (flags & NLM_F_EXCL)
1108                         return -EEXIST;
1109
1110                 if (READ_ONCE(fdb->dst) != source) {
1111                         WRITE_ONCE(fdb->dst, source);
1112                         modified = true;
1113                 }
1114
1115                 set_bit(BR_FDB_ADDED_BY_USER, &fdb->flags);
1116                 if (test_and_clear_bit(BR_FDB_DYNAMIC_LEARNED, &fdb->flags))
1117                         atomic_dec(&br->fdb_n_learned);
1118         }
1119
1120         if (fdb_to_nud(br, fdb) != state) {
1121                 if (state & NUD_PERMANENT) {
1122                         set_bit(BR_FDB_LOCAL, &fdb->flags);
1123                         if (!test_and_set_bit(BR_FDB_STATIC, &fdb->flags))
1124                                 fdb_add_hw_addr(br, addr);
1125                 } else if (state & NUD_NOARP) {
1126                         clear_bit(BR_FDB_LOCAL, &fdb->flags);
1127                         if (!test_and_set_bit(BR_FDB_STATIC, &fdb->flags))
1128                                 fdb_add_hw_addr(br, addr);
1129                 } else {
1130                         clear_bit(BR_FDB_LOCAL, &fdb->flags);
1131                         if (test_and_clear_bit(BR_FDB_STATIC, &fdb->flags))
1132                                 fdb_del_hw_addr(br, addr);
1133                 }
1134
1135                 modified = true;
1136         }
1137
1138         if (is_sticky != test_bit(BR_FDB_STICKY, &fdb->flags)) {
1139                 change_bit(BR_FDB_STICKY, &fdb->flags);
1140                 modified = true;
1141         }
1142
1143         if (test_and_clear_bit(BR_FDB_LOCKED, &fdb->flags))
1144                 modified = true;
1145
1146         if (fdb_handle_notify(fdb, notify))
1147                 modified = true;
1148
1149         fdb->used = jiffies;
1150         if (modified) {
1151                 if (refresh)
1152                         fdb->updated = jiffies;
1153                 fdb_notify(br, fdb, RTM_NEWNEIGH, true);
1154         }
1155
1156         return 0;
1157 }
1158
1159 static int __br_fdb_add(struct ndmsg *ndm, struct net_bridge *br,
1160                         struct net_bridge_port *p, const unsigned char *addr,
1161                         u16 nlh_flags, u16 vid, struct nlattr *nfea_tb[],
1162                         struct netlink_ext_ack *extack)
1163 {
1164         int err = 0;
1165
1166         if (ndm->ndm_flags & NTF_USE) {
1167                 if (!p) {
1168                         pr_info("bridge: RTM_NEWNEIGH %s with NTF_USE is not supported\n",
1169                                 br->dev->name);
1170                         return -EINVAL;
1171                 }
1172                 if (!nbp_state_should_learn(p))
1173                         return 0;
1174
1175                 local_bh_disable();
1176                 rcu_read_lock();
1177                 br_fdb_update(br, p, addr, vid, BIT(BR_FDB_ADDED_BY_USER));
1178                 rcu_read_unlock();
1179                 local_bh_enable();
1180         } else if (ndm->ndm_flags & NTF_EXT_LEARNED) {
1181                 if (!p && !(ndm->ndm_state & NUD_PERMANENT)) {
1182                         NL_SET_ERR_MSG_MOD(extack,
1183                                            "FDB entry towards bridge must be permanent");
1184                         return -EINVAL;
1185                 }
1186                 err = br_fdb_external_learn_add(br, p, addr, vid, false, true);
1187         } else {
1188                 spin_lock_bh(&br->hash_lock);
1189                 err = fdb_add_entry(br, p, addr, ndm, nlh_flags, vid, nfea_tb);
1190                 spin_unlock_bh(&br->hash_lock);
1191         }
1192
1193         return err;
1194 }
1195
1196 static const struct nla_policy br_nda_fdb_pol[NFEA_MAX + 1] = {
1197         [NFEA_ACTIVITY_NOTIFY]  = { .type = NLA_U8 },
1198         [NFEA_DONT_REFRESH]     = { .type = NLA_FLAG },
1199 };
1200
1201 /* Add new permanent fdb entry with RTM_NEWNEIGH */
1202 int br_fdb_add(struct ndmsg *ndm, struct nlattr *tb[],
1203                struct net_device *dev,
1204                const unsigned char *addr, u16 vid, u16 nlh_flags,
1205                struct netlink_ext_ack *extack)
1206 {
1207         struct nlattr *nfea_tb[NFEA_MAX + 1], *attr;
1208         struct net_bridge_vlan_group *vg;
1209         struct net_bridge_port *p = NULL;
1210         struct net_bridge_vlan *v;
1211         struct net_bridge *br = NULL;
1212         u32 ext_flags = 0;
1213         int err = 0;
1214
1215         trace_br_fdb_add(ndm, dev, addr, vid, nlh_flags);
1216
1217         if (!(ndm->ndm_state & (NUD_PERMANENT|NUD_NOARP|NUD_REACHABLE))) {
1218                 pr_info("bridge: RTM_NEWNEIGH with invalid state %#x\n", ndm->ndm_state);
1219                 return -EINVAL;
1220         }
1221
1222         if (is_zero_ether_addr(addr)) {
1223                 pr_info("bridge: RTM_NEWNEIGH with invalid ether address\n");
1224                 return -EINVAL;
1225         }
1226
1227         if (netif_is_bridge_master(dev)) {
1228                 br = netdev_priv(dev);
1229                 vg = br_vlan_group(br);
1230         } else {
1231                 p = br_port_get_rtnl(dev);
1232                 if (!p) {
1233                         pr_info("bridge: RTM_NEWNEIGH %s not a bridge port\n",
1234                                 dev->name);
1235                         return -EINVAL;
1236                 }
1237                 br = p->br;
1238                 vg = nbp_vlan_group(p);
1239         }
1240
1241         if (tb[NDA_FLAGS_EXT])
1242                 ext_flags = nla_get_u32(tb[NDA_FLAGS_EXT]);
1243
1244         if (ext_flags & NTF_EXT_LOCKED) {
1245                 NL_SET_ERR_MSG_MOD(extack, "Cannot add FDB entry with \"locked\" flag set");
1246                 return -EINVAL;
1247         }
1248
1249         if (tb[NDA_FDB_EXT_ATTRS]) {
1250                 attr = tb[NDA_FDB_EXT_ATTRS];
1251                 err = nla_parse_nested(nfea_tb, NFEA_MAX, attr,
1252                                        br_nda_fdb_pol, extack);
1253                 if (err)
1254                         return err;
1255         } else {
1256                 memset(nfea_tb, 0, sizeof(struct nlattr *) * (NFEA_MAX + 1));
1257         }
1258
1259         if (vid) {
1260                 v = br_vlan_find(vg, vid);
1261                 if (!v || !br_vlan_should_use(v)) {
1262                         pr_info("bridge: RTM_NEWNEIGH with unconfigured vlan %d on %s\n", vid, dev->name);
1263                         return -EINVAL;
1264                 }
1265
1266                 /* VID was specified, so use it. */
1267                 err = __br_fdb_add(ndm, br, p, addr, nlh_flags, vid, nfea_tb,
1268                                    extack);
1269         } else {
1270                 err = __br_fdb_add(ndm, br, p, addr, nlh_flags, 0, nfea_tb,
1271                                    extack);
1272                 if (err || !vg || !vg->num_vlans)
1273                         goto out;
1274
1275                 /* We have vlans configured on this port and user didn't
1276                  * specify a VLAN.  To be nice, add/update entry for every
1277                  * vlan on this port.
1278                  */
1279                 list_for_each_entry(v, &vg->vlan_list, vlist) {
1280                         if (!br_vlan_should_use(v))
1281                                 continue;
1282                         err = __br_fdb_add(ndm, br, p, addr, nlh_flags, v->vid,
1283                                            nfea_tb, extack);
1284                         if (err)
1285                                 goto out;
1286                 }
1287         }
1288
1289 out:
1290         return err;
1291 }
1292
1293 static int fdb_delete_by_addr_and_port(struct net_bridge *br,
1294                                        const struct net_bridge_port *p,
1295                                        const u8 *addr, u16 vlan)
1296 {
1297         struct net_bridge_fdb_entry *fdb;
1298
1299         fdb = br_fdb_find(br, addr, vlan);
1300         if (!fdb || READ_ONCE(fdb->dst) != p)
1301                 return -ENOENT;
1302
1303         fdb_delete(br, fdb, true);
1304
1305         return 0;
1306 }
1307
1308 static int __br_fdb_delete(struct net_bridge *br,
1309                            const struct net_bridge_port *p,
1310                            const unsigned char *addr, u16 vid)
1311 {
1312         int err;
1313
1314         spin_lock_bh(&br->hash_lock);
1315         err = fdb_delete_by_addr_and_port(br, p, addr, vid);
1316         spin_unlock_bh(&br->hash_lock);
1317
1318         return err;
1319 }
1320
1321 /* Remove neighbor entry with RTM_DELNEIGH */
1322 int br_fdb_delete(struct ndmsg *ndm, struct nlattr *tb[],
1323                   struct net_device *dev,
1324                   const unsigned char *addr, u16 vid,
1325                   struct netlink_ext_ack *extack)
1326 {
1327         struct net_bridge_vlan_group *vg;
1328         struct net_bridge_port *p = NULL;
1329         struct net_bridge_vlan *v;
1330         struct net_bridge *br;
1331         int err;
1332
1333         if (netif_is_bridge_master(dev)) {
1334                 br = netdev_priv(dev);
1335                 vg = br_vlan_group(br);
1336         } else {
1337                 p = br_port_get_rtnl(dev);
1338                 if (!p) {
1339                         pr_info("bridge: RTM_DELNEIGH %s not a bridge port\n",
1340                                 dev->name);
1341                         return -EINVAL;
1342                 }
1343                 vg = nbp_vlan_group(p);
1344                 br = p->br;
1345         }
1346
1347         if (vid) {
1348                 v = br_vlan_find(vg, vid);
1349                 if (!v) {
1350                         pr_info("bridge: RTM_DELNEIGH with unconfigured vlan %d on %s\n", vid, dev->name);
1351                         return -EINVAL;
1352                 }
1353
1354                 err = __br_fdb_delete(br, p, addr, vid);
1355         } else {
1356                 err = -ENOENT;
1357                 err &= __br_fdb_delete(br, p, addr, 0);
1358                 if (!vg || !vg->num_vlans)
1359                         return err;
1360
1361                 list_for_each_entry(v, &vg->vlan_list, vlist) {
1362                         if (!br_vlan_should_use(v))
1363                                 continue;
1364                         err &= __br_fdb_delete(br, p, addr, v->vid);
1365                 }
1366         }
1367
1368         return err;
1369 }
1370
1371 int br_fdb_sync_static(struct net_bridge *br, struct net_bridge_port *p)
1372 {
1373         struct net_bridge_fdb_entry *f, *tmp;
1374         int err = 0;
1375
1376         ASSERT_RTNL();
1377
1378         /* the key here is that static entries change only under rtnl */
1379         rcu_read_lock();
1380         hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
1381                 /* We only care for static entries */
1382                 if (!test_bit(BR_FDB_STATIC, &f->flags))
1383                         continue;
1384                 err = dev_uc_add(p->dev, f->key.addr.addr);
1385                 if (err)
1386                         goto rollback;
1387         }
1388 done:
1389         rcu_read_unlock();
1390
1391         return err;
1392
1393 rollback:
1394         hlist_for_each_entry_rcu(tmp, &br->fdb_list, fdb_node) {
1395                 /* We only care for static entries */
1396                 if (!test_bit(BR_FDB_STATIC, &tmp->flags))
1397                         continue;
1398                 if (tmp == f)
1399                         break;
1400                 dev_uc_del(p->dev, tmp->key.addr.addr);
1401         }
1402
1403         goto done;
1404 }
1405
1406 void br_fdb_unsync_static(struct net_bridge *br, struct net_bridge_port *p)
1407 {
1408         struct net_bridge_fdb_entry *f;
1409
1410         ASSERT_RTNL();
1411
1412         rcu_read_lock();
1413         hlist_for_each_entry_rcu(f, &br->fdb_list, fdb_node) {
1414                 /* We only care for static entries */
1415                 if (!test_bit(BR_FDB_STATIC, &f->flags))
1416                         continue;
1417
1418                 dev_uc_del(p->dev, f->key.addr.addr);
1419         }
1420         rcu_read_unlock();
1421 }
1422
1423 int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p,
1424                               const unsigned char *addr, u16 vid, bool locked,
1425                               bool swdev_notify)
1426 {
1427         struct net_bridge_fdb_entry *fdb;
1428         bool modified = false;
1429         int err = 0;
1430
1431         trace_br_fdb_external_learn_add(br, p, addr, vid);
1432
1433         if (locked && (!p || !(p->flags & BR_PORT_MAB)))
1434                 return -EINVAL;
1435
1436         spin_lock_bh(&br->hash_lock);
1437
1438         fdb = br_fdb_find(br, addr, vid);
1439         if (!fdb) {
1440                 unsigned long flags = BIT(BR_FDB_ADDED_BY_EXT_LEARN);
1441
1442                 if (swdev_notify)
1443                         flags |= BIT(BR_FDB_ADDED_BY_USER);
1444
1445                 if (!p)
1446                         flags |= BIT(BR_FDB_LOCAL);
1447
1448                 if (locked)
1449                         flags |= BIT(BR_FDB_LOCKED);
1450
1451                 fdb = fdb_create(br, p, addr, vid, flags);
1452                 if (!fdb) {
1453                         err = -ENOMEM;
1454                         goto err_unlock;
1455                 }
1456                 fdb_notify(br, fdb, RTM_NEWNEIGH, swdev_notify);
1457         } else {
1458                 if (locked &&
1459                     (!test_bit(BR_FDB_LOCKED, &fdb->flags) ||
1460                      READ_ONCE(fdb->dst) != p)) {
1461                         err = -EINVAL;
1462                         goto err_unlock;
1463                 }
1464
1465                 fdb->updated = jiffies;
1466
1467                 if (READ_ONCE(fdb->dst) != p) {
1468                         WRITE_ONCE(fdb->dst, p);
1469                         modified = true;
1470                 }
1471
1472                 if (test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags)) {
1473                         /* Refresh entry */
1474                         fdb->used = jiffies;
1475                 } else if (!test_bit(BR_FDB_ADDED_BY_USER, &fdb->flags)) {
1476                         /* Take over SW learned entry */
1477                         set_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags);
1478                         modified = true;
1479                 }
1480
1481                 if (locked != test_bit(BR_FDB_LOCKED, &fdb->flags)) {
1482                         change_bit(BR_FDB_LOCKED, &fdb->flags);
1483                         modified = true;
1484                 }
1485
1486                 if (swdev_notify)
1487                         set_bit(BR_FDB_ADDED_BY_USER, &fdb->flags);
1488
1489                 if (!p)
1490                         set_bit(BR_FDB_LOCAL, &fdb->flags);
1491
1492                 if ((swdev_notify || !p) &&
1493                     test_and_clear_bit(BR_FDB_DYNAMIC_LEARNED, &fdb->flags))
1494                         atomic_dec(&br->fdb_n_learned);
1495
1496                 if (modified)
1497                         fdb_notify(br, fdb, RTM_NEWNEIGH, swdev_notify);
1498         }
1499
1500 err_unlock:
1501         spin_unlock_bh(&br->hash_lock);
1502
1503         return err;
1504 }
1505
1506 int br_fdb_external_learn_del(struct net_bridge *br, struct net_bridge_port *p,
1507                               const unsigned char *addr, u16 vid,
1508                               bool swdev_notify)
1509 {
1510         struct net_bridge_fdb_entry *fdb;
1511         int err = 0;
1512
1513         spin_lock_bh(&br->hash_lock);
1514
1515         fdb = br_fdb_find(br, addr, vid);
1516         if (fdb && test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &fdb->flags))
1517                 fdb_delete(br, fdb, swdev_notify);
1518         else
1519                 err = -ENOENT;
1520
1521         spin_unlock_bh(&br->hash_lock);
1522
1523         return err;
1524 }
1525
1526 void br_fdb_offloaded_set(struct net_bridge *br, struct net_bridge_port *p,
1527                           const unsigned char *addr, u16 vid, bool offloaded)
1528 {
1529         struct net_bridge_fdb_entry *fdb;
1530
1531         spin_lock_bh(&br->hash_lock);
1532
1533         fdb = br_fdb_find(br, addr, vid);
1534         if (fdb && offloaded != test_bit(BR_FDB_OFFLOADED, &fdb->flags))
1535                 change_bit(BR_FDB_OFFLOADED, &fdb->flags);
1536
1537         spin_unlock_bh(&br->hash_lock);
1538 }
1539
1540 void br_fdb_clear_offload(const struct net_device *dev, u16 vid)
1541 {
1542         struct net_bridge_fdb_entry *f;
1543         struct net_bridge_port *p;
1544
1545         ASSERT_RTNL();
1546
1547         p = br_port_get_rtnl(dev);
1548         if (!p)
1549                 return;
1550
1551         spin_lock_bh(&p->br->hash_lock);
1552         hlist_for_each_entry(f, &p->br->fdb_list, fdb_node) {
1553                 if (f->dst == p && f->key.vlan_id == vid)
1554                         clear_bit(BR_FDB_OFFLOADED, &f->flags);
1555         }
1556         spin_unlock_bh(&p->br->hash_lock);
1557 }
1558 EXPORT_SYMBOL_GPL(br_fdb_clear_offload);