1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * net/sched/act_mirred.c packet mirroring and redirect actions 4 * 5 * Authors: Jamal Hadi Salim (2002-4) 6 * 7 * TODO: Add ingress support (and socket redirect support) 8 */ 9 10 #include <linux/types.h> 11 #include <linux/kernel.h> 12 #include <linux/string.h> 13 #include <linux/errno.h> 14 #include <linux/skbuff.h> 15 #include <linux/rtnetlink.h> 16 #include <linux/module.h> 17 #include <linux/init.h> 18 #include <linux/gfp.h> 19 #include <linux/if_arp.h> 20 #include <net/net_namespace.h> 21 #include <net/netlink.h> 22 #include <net/dst.h> 23 #include <net/pkt_sched.h> 24 #include <net/pkt_cls.h> 25 #include <linux/tc_act/tc_mirred.h> 26 #include <net/tc_act/tc_mirred.h> 27 #include <net/tc_wrapper.h> 28 29 static LIST_HEAD(mirred_list); 30 static DEFINE_SPINLOCK(mirred_list_lock); 31 32 #define MIRRED_NEST_LIMIT 4 33 static DEFINE_PER_CPU(unsigned int, mirred_nest_level); 34 35 static bool tcf_mirred_is_act_redirect(int action) 36 { 37 return action == TCA_EGRESS_REDIR || action == TCA_INGRESS_REDIR; 38 } 39 40 static bool tcf_mirred_act_wants_ingress(int action) 41 { 42 switch (action) { 43 case TCA_EGRESS_REDIR: 44 case TCA_EGRESS_MIRROR: 45 return false; 46 case TCA_INGRESS_REDIR: 47 case TCA_INGRESS_MIRROR: 48 return true; 49 default: 50 BUG(); 51 } 52 } 53 54 static bool tcf_mirred_can_reinsert(int action) 55 { 56 switch (action) { 57 case TC_ACT_SHOT: 58 case TC_ACT_STOLEN: 59 case TC_ACT_QUEUED: 60 case TC_ACT_TRAP: 61 return true; 62 } 63 return false; 64 } 65 66 static struct net_device *tcf_mirred_dev_dereference(struct tcf_mirred *m) 67 { 68 return rcu_dereference_protected(m->tcfm_dev, 69 lockdep_is_held(&m->tcf_lock)); 70 } 71 72 static void tcf_mirred_release(struct tc_action *a) 73 { 74 struct tcf_mirred *m = to_mirred(a); 75 struct net_device *dev; 76 77 spin_lock(&mirred_list_lock); 78 list_del(&m->tcfm_list); 79 spin_unlock(&mirred_list_lock); 80 81 /* last reference to action, no need to lock */ 82 dev = rcu_dereference_protected(m->tcfm_dev, 1); 83 netdev_put(dev, &m->tcfm_dev_tracker); 84 } 85 86 static const struct nla_policy mirred_policy[TCA_MIRRED_MAX + 1] = { 87 [TCA_MIRRED_PARMS] = { .len = sizeof(struct tc_mirred) }, 88 [TCA_MIRRED_BLOCKID] = NLA_POLICY_MIN(NLA_U32, 1), 89 }; 90 91 static struct tc_action_ops act_mirred_ops; 92 93 static void tcf_mirred_replace_dev(struct tcf_mirred *m, 94 struct net_device *ndev) 95 { 96 struct net_device *odev; 97 98 odev = rcu_replace_pointer(m->tcfm_dev, ndev, 99 lockdep_is_held(&m->tcf_lock)); 100 netdev_put(odev, &m->tcfm_dev_tracker); 101 } 102 103 static int tcf_mirred_init(struct net *net, struct nlattr *nla, 104 struct nlattr *est, struct tc_action **a, 105 struct tcf_proto *tp, 106 u32 flags, struct netlink_ext_ack *extack) 107 { 108 struct tc_action_net *tn = net_generic(net, act_mirred_ops.net_id); 109 bool bind = flags & TCA_ACT_FLAGS_BIND; 110 struct nlattr *tb[TCA_MIRRED_MAX + 1]; 111 struct tcf_chain *goto_ch = NULL; 112 bool mac_header_xmit = false; 113 struct tc_mirred *parm; 114 struct tcf_mirred *m; 115 bool exists = false; 116 int ret, err; 117 u32 index; 118 119 if (!nla) { 120 NL_SET_ERR_MSG_MOD(extack, "Mirred requires attributes to be passed"); 121 return -EINVAL; 122 } 123 ret = nla_parse_nested_deprecated(tb, TCA_MIRRED_MAX, nla, 124 mirred_policy, extack); 125 if (ret < 0) 126 return ret; 127 if (!tb[TCA_MIRRED_PARMS]) { 128 NL_SET_ERR_MSG_MOD(extack, "Missing required mirred parameters"); 129 return -EINVAL; 130 } 131 parm = nla_data(tb[TCA_MIRRED_PARMS]); 132 index = parm->index; 133 err = tcf_idr_check_alloc(tn, &index, a, bind); 134 if (err < 0) 135 return err; 136 exists = err; 137 if (exists && bind) 138 return ACT_P_BOUND; 139 140 if (tb[TCA_MIRRED_BLOCKID] && parm->ifindex) { 141 NL_SET_ERR_MSG_MOD(extack, 142 "Cannot specify Block ID and dev simultaneously"); 143 if (exists) 144 tcf_idr_release(*a, bind); 145 else 146 tcf_idr_cleanup(tn, index); 147 148 return -EINVAL; 149 } 150 151 switch (parm->eaction) { 152 case TCA_EGRESS_MIRROR: 153 case TCA_EGRESS_REDIR: 154 case TCA_INGRESS_REDIR: 155 case TCA_INGRESS_MIRROR: 156 break; 157 default: 158 if (exists) 159 tcf_idr_release(*a, bind); 160 else 161 tcf_idr_cleanup(tn, index); 162 NL_SET_ERR_MSG_MOD(extack, "Unknown mirred option"); 163 return -EINVAL; 164 } 165 166 if (!exists) { 167 if (!parm->ifindex && !tb[TCA_MIRRED_BLOCKID]) { 168 tcf_idr_cleanup(tn, index); 169 NL_SET_ERR_MSG_MOD(extack, 170 "Must specify device or block"); 171 return -EINVAL; 172 } 173 ret = tcf_idr_create_from_flags(tn, index, est, a, 174 &act_mirred_ops, bind, flags); 175 if (ret) { 176 tcf_idr_cleanup(tn, index); 177 return ret; 178 } 179 ret = ACT_P_CREATED; 180 } else if (!(flags & TCA_ACT_FLAGS_REPLACE)) { 181 tcf_idr_release(*a, bind); 182 return -EEXIST; 183 } 184 185 m = to_mirred(*a); 186 if (ret == ACT_P_CREATED) 187 INIT_LIST_HEAD(&m->tcfm_list); 188 189 err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack); 190 if (err < 0) 191 goto release_idr; 192 193 spin_lock_bh(&m->tcf_lock); 194 195 if (parm->ifindex) { 196 struct net_device *ndev; 197 198 ndev = dev_get_by_index(net, parm->ifindex); 199 if (!ndev) { 200 spin_unlock_bh(&m->tcf_lock); 201 err = -ENODEV; 202 goto put_chain; 203 } 204 mac_header_xmit = dev_is_mac_header_xmit(ndev); 205 tcf_mirred_replace_dev(m, ndev); 206 netdev_tracker_alloc(ndev, &m->tcfm_dev_tracker, GFP_ATOMIC); 207 m->tcfm_mac_header_xmit = mac_header_xmit; 208 m->tcfm_blockid = 0; 209 } else if (tb[TCA_MIRRED_BLOCKID]) { 210 tcf_mirred_replace_dev(m, NULL); 211 m->tcfm_mac_header_xmit = false; 212 m->tcfm_blockid = nla_get_u32(tb[TCA_MIRRED_BLOCKID]); 213 } 214 goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch); 215 m->tcfm_eaction = parm->eaction; 216 spin_unlock_bh(&m->tcf_lock); 217 if (goto_ch) 218 tcf_chain_put_by_act(goto_ch); 219 220 if (ret == ACT_P_CREATED) { 221 spin_lock(&mirred_list_lock); 222 list_add(&m->tcfm_list, &mirred_list); 223 spin_unlock(&mirred_list_lock); 224 } 225 226 return ret; 227 put_chain: 228 if (goto_ch) 229 tcf_chain_put_by_act(goto_ch); 230 release_idr: 231 tcf_idr_release(*a, bind); 232 return err; 233 } 234 235 static bool is_mirred_nested(void) 236 { 237 return unlikely(__this_cpu_read(mirred_nest_level) > 1); 238 } 239 240 static int tcf_mirred_forward(bool want_ingress, struct sk_buff *skb) 241 { 242 int err; 243 244 if (!want_ingress) 245 err = tcf_dev_queue_xmit(skb, dev_queue_xmit); 246 else if (is_mirred_nested()) 247 err = netif_rx(skb); 248 else 249 err = netif_receive_skb(skb); 250 251 return err; 252 } 253 254 static int tcf_mirred_to_dev(struct sk_buff *skb, struct tcf_mirred *m, 255 struct net_device *dev, 256 const bool m_mac_header_xmit, int m_eaction, 257 int retval) 258 { 259 struct sk_buff *skb_to_send = skb; 260 bool want_ingress; 261 bool is_redirect; 262 bool expects_nh; 263 bool at_ingress; 264 bool dont_clone; 265 int mac_len; 266 bool at_nh; 267 int err; 268 269 is_redirect = tcf_mirred_is_act_redirect(m_eaction); 270 if (unlikely(!(dev->flags & IFF_UP)) || !netif_carrier_ok(dev)) { 271 net_notice_ratelimited("tc mirred to Houston: device %s is down\n", 272 dev->name); 273 err = -ENODEV; 274 goto out; 275 } 276 277 /* we could easily avoid the clone only if called by ingress and clsact; 278 * since we can't easily detect the clsact caller, skip clone only for 279 * ingress - that covers the TC S/W datapath. 280 */ 281 at_ingress = skb_at_tc_ingress(skb); 282 dont_clone = skb_at_tc_ingress(skb) && is_redirect && 283 tcf_mirred_can_reinsert(retval); 284 if (!dont_clone) { 285 skb_to_send = skb_clone(skb, GFP_ATOMIC); 286 if (!skb_to_send) { 287 err = -ENOMEM; 288 goto out; 289 } 290 } 291 292 want_ingress = tcf_mirred_act_wants_ingress(m_eaction); 293 294 /* All mirred/redirected skbs should clear previous ct info */ 295 nf_reset_ct(skb_to_send); 296 if (want_ingress && !at_ingress) /* drop dst for egress -> ingress */ 297 skb_dst_drop(skb_to_send); 298 299 expects_nh = want_ingress || !m_mac_header_xmit; 300 at_nh = skb->data == skb_network_header(skb); 301 if (at_nh != expects_nh) { 302 mac_len = at_ingress ? skb->mac_len : 303 skb_network_offset(skb); 304 if (expects_nh) { 305 /* target device/action expect data at nh */ 306 skb_pull_rcsum(skb_to_send, mac_len); 307 } else { 308 /* target device/action expect data at mac */ 309 skb_push_rcsum(skb_to_send, mac_len); 310 } 311 } 312 313 skb_to_send->skb_iif = skb->dev->ifindex; 314 skb_to_send->dev = dev; 315 316 if (is_redirect) { 317 if (skb == skb_to_send) 318 retval = TC_ACT_CONSUMED; 319 320 skb_set_redirected(skb_to_send, skb_to_send->tc_at_ingress); 321 322 err = tcf_mirred_forward(want_ingress, skb_to_send); 323 } else { 324 err = tcf_mirred_forward(want_ingress, skb_to_send); 325 } 326 327 if (err) { 328 out: 329 tcf_action_inc_overlimit_qstats(&m->common); 330 if (is_redirect) 331 retval = TC_ACT_SHOT; 332 } 333 334 return retval; 335 } 336 337 static int tcf_blockcast_redir(struct sk_buff *skb, struct tcf_mirred *m, 338 struct tcf_block *block, int m_eaction, 339 const u32 exception_ifindex, int retval) 340 { 341 struct net_device *dev_prev = NULL; 342 struct net_device *dev = NULL; 343 unsigned long index; 344 int mirred_eaction; 345 346 mirred_eaction = tcf_mirred_act_wants_ingress(m_eaction) ? 347 TCA_INGRESS_MIRROR : TCA_EGRESS_MIRROR; 348 349 xa_for_each(&block->ports, index, dev) { 350 if (index == exception_ifindex) 351 continue; 352 353 if (!dev_prev) 354 goto assign_prev; 355 356 tcf_mirred_to_dev(skb, m, dev_prev, 357 dev_is_mac_header_xmit(dev), 358 mirred_eaction, retval); 359 assign_prev: 360 dev_prev = dev; 361 } 362 363 if (dev_prev) 364 return tcf_mirred_to_dev(skb, m, dev_prev, 365 dev_is_mac_header_xmit(dev_prev), 366 m_eaction, retval); 367 368 return retval; 369 } 370 371 static int tcf_blockcast_mirror(struct sk_buff *skb, struct tcf_mirred *m, 372 struct tcf_block *block, int m_eaction, 373 const u32 exception_ifindex, int retval) 374 { 375 struct net_device *dev = NULL; 376 unsigned long index; 377 378 xa_for_each(&block->ports, index, dev) { 379 if (index == exception_ifindex) 380 continue; 381 382 tcf_mirred_to_dev(skb, m, dev, 383 dev_is_mac_header_xmit(dev), 384 m_eaction, retval); 385 } 386 387 return retval; 388 } 389 390 static int tcf_blockcast(struct sk_buff *skb, struct tcf_mirred *m, 391 const u32 blockid, struct tcf_result *res, 392 int retval) 393 { 394 const u32 exception_ifindex = skb->dev->ifindex; 395 struct tcf_block *block; 396 bool is_redirect; 397 int m_eaction; 398 399 m_eaction = READ_ONCE(m->tcfm_eaction); 400 is_redirect = tcf_mirred_is_act_redirect(m_eaction); 401 402 /* we are already under rcu protection, so can call block lookup 403 * directly. 404 */ 405 block = tcf_block_lookup(dev_net(skb->dev), blockid); 406 if (!block || xa_empty(&block->ports)) { 407 tcf_action_inc_overlimit_qstats(&m->common); 408 return retval; 409 } 410 411 if (is_redirect) 412 return tcf_blockcast_redir(skb, m, block, m_eaction, 413 exception_ifindex, retval); 414 415 /* If it's not redirect, it is mirror */ 416 return tcf_blockcast_mirror(skb, m, block, m_eaction, exception_ifindex, 417 retval); 418 } 419 420 TC_INDIRECT_SCOPE int tcf_mirred_act(struct sk_buff *skb, 421 const struct tc_action *a, 422 struct tcf_result *res) 423 { 424 struct tcf_mirred *m = to_mirred(a); 425 int retval = READ_ONCE(m->tcf_action); 426 unsigned int nest_level; 427 bool m_mac_header_xmit; 428 struct net_device *dev; 429 int m_eaction; 430 u32 blockid; 431 432 nest_level = __this_cpu_inc_return(mirred_nest_level); 433 if (unlikely(nest_level > MIRRED_NEST_LIMIT)) { 434 net_warn_ratelimited("Packet exceeded mirred recursion limit on dev %s\n", 435 netdev_name(skb->dev)); 436 retval = TC_ACT_SHOT; 437 goto dec_nest_level; 438 } 439 440 tcf_lastuse_update(&m->tcf_tm); 441 tcf_action_update_bstats(&m->common, skb); 442 443 blockid = READ_ONCE(m->tcfm_blockid); 444 if (blockid) { 445 retval = tcf_blockcast(skb, m, blockid, res, retval); 446 goto dec_nest_level; 447 } 448 449 dev = rcu_dereference_bh(m->tcfm_dev); 450 if (unlikely(!dev)) { 451 pr_notice_once("tc mirred: target device is gone\n"); 452 tcf_action_inc_overlimit_qstats(&m->common); 453 goto dec_nest_level; 454 } 455 456 m_mac_header_xmit = READ_ONCE(m->tcfm_mac_header_xmit); 457 m_eaction = READ_ONCE(m->tcfm_eaction); 458 459 retval = tcf_mirred_to_dev(skb, m, dev, m_mac_header_xmit, m_eaction, 460 retval); 461 462 dec_nest_level: 463 __this_cpu_dec(mirred_nest_level); 464 465 return retval; 466 } 467 468 static void tcf_stats_update(struct tc_action *a, u64 bytes, u64 packets, 469 u64 drops, u64 lastuse, bool hw) 470 { 471 struct tcf_mirred *m = to_mirred(a); 472 struct tcf_t *tm = &m->tcf_tm; 473 474 tcf_action_update_stats(a, bytes, packets, drops, hw); 475 tm->lastuse = max_t(u64, tm->lastuse, lastuse); 476 } 477 478 static int tcf_mirred_dump(struct sk_buff *skb, struct tc_action *a, int bind, 479 int ref) 480 { 481 unsigned char *b = skb_tail_pointer(skb); 482 struct tcf_mirred *m = to_mirred(a); 483 struct tc_mirred opt = { 484 .index = m->tcf_index, 485 .refcnt = refcount_read(&m->tcf_refcnt) - ref, 486 .bindcnt = atomic_read(&m->tcf_bindcnt) - bind, 487 }; 488 struct net_device *dev; 489 struct tcf_t t; 490 u32 blockid; 491 492 spin_lock_bh(&m->tcf_lock); 493 opt.action = m->tcf_action; 494 opt.eaction = m->tcfm_eaction; 495 dev = tcf_mirred_dev_dereference(m); 496 if (dev) 497 opt.ifindex = dev->ifindex; 498 499 if (nla_put(skb, TCA_MIRRED_PARMS, sizeof(opt), &opt)) 500 goto nla_put_failure; 501 502 blockid = m->tcfm_blockid; 503 if (blockid && nla_put_u32(skb, TCA_MIRRED_BLOCKID, blockid)) 504 goto nla_put_failure; 505 506 tcf_tm_dump(&t, &m->tcf_tm); 507 if (nla_put_64bit(skb, TCA_MIRRED_TM, sizeof(t), &t, TCA_MIRRED_PAD)) 508 goto nla_put_failure; 509 spin_unlock_bh(&m->tcf_lock); 510 511 return skb->len; 512 513 nla_put_failure: 514 spin_unlock_bh(&m->tcf_lock); 515 nlmsg_trim(skb, b); 516 return -1; 517 } 518 519 static int mirred_device_event(struct notifier_block *unused, 520 unsigned long event, void *ptr) 521 { 522 struct net_device *dev = netdev_notifier_info_to_dev(ptr); 523 struct tcf_mirred *m; 524 525 ASSERT_RTNL(); 526 if (event == NETDEV_UNREGISTER) { 527 spin_lock(&mirred_list_lock); 528 list_for_each_entry(m, &mirred_list, tcfm_list) { 529 spin_lock_bh(&m->tcf_lock); 530 if (tcf_mirred_dev_dereference(m) == dev) { 531 netdev_put(dev, &m->tcfm_dev_tracker); 532 /* Note : no rcu grace period necessary, as 533 * net_device are already rcu protected. 534 */ 535 RCU_INIT_POINTER(m->tcfm_dev, NULL); 536 } else if (m->tcfm_blockid) { 537 m->tcfm_blockid = 0; 538 } 539 spin_unlock_bh(&m->tcf_lock); 540 } 541 spin_unlock(&mirred_list_lock); 542 } 543 544 return NOTIFY_DONE; 545 } 546 547 static struct notifier_block mirred_device_notifier = { 548 .notifier_call = mirred_device_event, 549 }; 550 551 static void tcf_mirred_dev_put(void *priv) 552 { 553 struct net_device *dev = priv; 554 555 dev_put(dev); 556 } 557 558 static struct net_device * 559 tcf_mirred_get_dev(const struct tc_action *a, 560 tc_action_priv_destructor *destructor) 561 { 562 struct tcf_mirred *m = to_mirred(a); 563 struct net_device *dev; 564 565 rcu_read_lock(); 566 dev = rcu_dereference(m->tcfm_dev); 567 if (dev) { 568 dev_hold(dev); 569 *destructor = tcf_mirred_dev_put; 570 } 571 rcu_read_unlock(); 572 573 return dev; 574 } 575 576 static size_t tcf_mirred_get_fill_size(const struct tc_action *act) 577 { 578 return nla_total_size(sizeof(struct tc_mirred)); 579 } 580 581 static void tcf_offload_mirred_get_dev(struct flow_action_entry *entry, 582 const struct tc_action *act) 583 { 584 entry->dev = act->ops->get_dev(act, &entry->destructor); 585 if (!entry->dev) 586 return; 587 entry->destructor_priv = entry->dev; 588 } 589 590 static int tcf_mirred_offload_act_setup(struct tc_action *act, void *entry_data, 591 u32 *index_inc, bool bind, 592 struct netlink_ext_ack *extack) 593 { 594 if (bind) { 595 struct flow_action_entry *entry = entry_data; 596 597 if (is_tcf_mirred_egress_redirect(act)) { 598 entry->id = FLOW_ACTION_REDIRECT; 599 tcf_offload_mirred_get_dev(entry, act); 600 } else if (is_tcf_mirred_egress_mirror(act)) { 601 entry->id = FLOW_ACTION_MIRRED; 602 tcf_offload_mirred_get_dev(entry, act); 603 } else if (is_tcf_mirred_ingress_redirect(act)) { 604 entry->id = FLOW_ACTION_REDIRECT_INGRESS; 605 tcf_offload_mirred_get_dev(entry, act); 606 } else if (is_tcf_mirred_ingress_mirror(act)) { 607 entry->id = FLOW_ACTION_MIRRED_INGRESS; 608 tcf_offload_mirred_get_dev(entry, act); 609 } else { 610 NL_SET_ERR_MSG_MOD(extack, "Unsupported mirred offload"); 611 return -EOPNOTSUPP; 612 } 613 *index_inc = 1; 614 } else { 615 struct flow_offload_action *fl_action = entry_data; 616 617 if (is_tcf_mirred_egress_redirect(act)) 618 fl_action->id = FLOW_ACTION_REDIRECT; 619 else if (is_tcf_mirred_egress_mirror(act)) 620 fl_action->id = FLOW_ACTION_MIRRED; 621 else if (is_tcf_mirred_ingress_redirect(act)) 622 fl_action->id = FLOW_ACTION_REDIRECT_INGRESS; 623 else if (is_tcf_mirred_ingress_mirror(act)) 624 fl_action->id = FLOW_ACTION_MIRRED_INGRESS; 625 else 626 return -EOPNOTSUPP; 627 } 628 629 return 0; 630 } 631 632 static struct tc_action_ops act_mirred_ops = { 633 .kind = "mirred", 634 .id = TCA_ID_MIRRED, 635 .owner = THIS_MODULE, 636 .act = tcf_mirred_act, 637 .stats_update = tcf_stats_update, 638 .dump = tcf_mirred_dump, 639 .cleanup = tcf_mirred_release, 640 .init = tcf_mirred_init, 641 .get_fill_size = tcf_mirred_get_fill_size, 642 .offload_act_setup = tcf_mirred_offload_act_setup, 643 .size = sizeof(struct tcf_mirred), 644 .get_dev = tcf_mirred_get_dev, 645 }; 646 MODULE_ALIAS_NET_ACT("mirred"); 647 648 static __net_init int mirred_init_net(struct net *net) 649 { 650 struct tc_action_net *tn = net_generic(net, act_mirred_ops.net_id); 651 652 return tc_action_net_init(net, tn, &act_mirred_ops); 653 } 654 655 static void __net_exit mirred_exit_net(struct list_head *net_list) 656 { 657 tc_action_net_exit(net_list, act_mirred_ops.net_id); 658 } 659 660 static struct pernet_operations mirred_net_ops = { 661 .init = mirred_init_net, 662 .exit_batch = mirred_exit_net, 663 .id = &act_mirred_ops.net_id, 664 .size = sizeof(struct tc_action_net), 665 }; 666 667 MODULE_AUTHOR("Jamal Hadi Salim(2002)"); 668 MODULE_DESCRIPTION("Device Mirror/redirect actions"); 669 MODULE_LICENSE("GPL"); 670 671 static int __init mirred_init_module(void) 672 { 673 int err = register_netdevice_notifier(&mirred_device_notifier); 674 if (err) 675 return err; 676 677 pr_info("Mirror/redirect action on\n"); 678 err = tcf_register_action(&act_mirred_ops, &mirred_net_ops); 679 if (err) 680 unregister_netdevice_notifier(&mirred_device_notifier); 681 682 return err; 683 } 684 685 static void __exit mirred_cleanup_module(void) 686 { 687 tcf_unregister_action(&act_mirred_ops, &mirred_net_ops); 688 unregister_netdevice_notifier(&mirred_device_notifier); 689 } 690 691 module_init(mirred_init_module); 692 module_exit(mirred_cleanup_module); 693