net/sched/cls_api.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * net/sched/cls_api.c  Packet classifier API.
   4  *
   5  * Authors:     Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
   6  *
   7  * Changes:
   8  *
   9  * Eduardo J. Blanco <ejbs@netlabs.com.uy> :990222: kmod support
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/types.h>
  14 #include <linux/kernel.h>
  15 #include <linux/string.h>
  16 #include <linux/errno.h>
  17 #include <linux/err.h>
  18 #include <linux/skbuff.h>
  19 #include <linux/init.h>
  20 #include <linux/kmod.h>
  21 #include <linux/slab.h>
  22 #include <linux/idr.h>
  23 #include <linux/jhash.h>
  24 #include <linux/rculist.h>
  25 #include <net/net_namespace.h>
  26 #include <net/sock.h>
  27 #include <net/netlink.h>
  28 #include <net/pkt_sched.h>
  29 #include <net/pkt_cls.h>
  30 #include <net/tc_act/tc_pedit.h>
  31 #include <net/tc_act/tc_mirred.h>
  32 #include <net/tc_act/tc_vlan.h>
  33 #include <net/tc_act/tc_tunnel_key.h>
  34 #include <net/tc_act/tc_csum.h>
  35 #include <net/tc_act/tc_gact.h>
  36 #include <net/tc_act/tc_police.h>
  37 #include <net/tc_act/tc_sample.h>
  38 #include <net/tc_act/tc_skbedit.h>
  39 #include <net/tc_act/tc_ct.h>
  40 #include <net/tc_act/tc_mpls.h>
  41 #include <net/tc_act/tc_gate.h>
  42 #include <net/flow_offload.h>
  43
  44 /* The list of all installed classifier types */
  45 static LIST_HEAD(tcf_proto_base);
  46
  47 /* Protects list of registered TC modules. It is pure SMP lock. */
  48 static DEFINE_RWLOCK(cls_mod_lock);
  49
  50 static u32 destroy_obj_hashfn(const struct tcf_proto *tp)
  51 {
  52         return jhash_3words(tp->chain->index, tp->prio,
  53                             (__force __u32)tp->protocol, 0);
  54 }
  55
  56 static void tcf_proto_signal_destroying(struct tcf_chain *chain,
  57                                         struct tcf_proto *tp)
  58 {
  59         struct tcf_block *block = chain->block;
  60
  61         mutex_lock(&block->proto_destroy_lock);
  62         hash_add_rcu(block->proto_destroy_ht, &tp->destroy_ht_node,
  63                      destroy_obj_hashfn(tp));
  64         mutex_unlock(&block->proto_destroy_lock);
  65 }
  66
  67 static bool tcf_proto_cmp(const struct tcf_proto *tp1,
  68                           const struct tcf_proto *tp2)
  69 {
  70         return tp1->chain->index == tp2->chain->index &&
  71                tp1->prio == tp2->prio &&
  72                tp1->protocol == tp2->protocol;
  73 }
  74
  75 static bool tcf_proto_exists_destroying(struct tcf_chain *chain,
  76                                         struct tcf_proto *tp)
  77 {
  78         u32 hash = destroy_obj_hashfn(tp);
  79         struct tcf_proto *iter;
  80         bool found = false;
  81
  82         rcu_read_lock();
  83         hash_for_each_possible_rcu(chain->block->proto_destroy_ht, iter,
  84                                    destroy_ht_node, hash) {
  85                 if (tcf_proto_cmp(tp, iter)) {
  86                         found = true;
  87                         break;
  88                 }
  89         }
  90         rcu_read_unlock();
  91
  92         return found;
  93 }
  94
  95 static void
  96 tcf_proto_signal_destroyed(struct tcf_chain *chain, struct tcf_proto *tp)
  97 {
  98         struct tcf_block *block = chain->block;
  99
 100         mutex_lock(&block->proto_destroy_lock);
 101         if (hash_hashed(&tp->destroy_ht_node))
 102                 hash_del_rcu(&tp->destroy_ht_node);
 103         mutex_unlock(&block->proto_destroy_lock);
 104 }
 105
 106 /* Find classifier type by string name */
 107
 108 static const struct tcf_proto_ops *__tcf_proto_lookup_ops(const char *kind)
 109 {
 110         const struct tcf_proto_ops *t, *res = NULL;
 111
 112         if (kind) {
 113                 read_lock(&cls_mod_lock);
 114                 list_for_each_entry(t, &tcf_proto_base, head) {
 115                         if (strcmp(kind, t->kind) == 0) {
 116                                 if (try_module_get(t->owner))
 117                                         res = t;
 118                                 break;
 119                         }
 120                 }
 121                 read_unlock(&cls_mod_lock);
 122         }
 123         return res;
 124 }
 125
 126 static const struct tcf_proto_ops *
 127 tcf_proto_lookup_ops(const char *kind, bool rtnl_held,
 128                      struct netlink_ext_ack *extack)
 129 {
 130         const struct tcf_proto_ops *ops;
 131
 132         ops = __tcf_proto_lookup_ops(kind);
 133         if (ops)
 134                 return ops;
 135 #ifdef CONFIG_MODULES
 136         if (rtnl_held)
 137                 rtnl_unlock();
 138         request_module("cls_%s", kind);
 139         if (rtnl_held)
 140                 rtnl_lock();
 141         ops = __tcf_proto_lookup_ops(kind);
 142         /* We dropped the RTNL semaphore in order to perform
 143          * the module load. So, even if we succeeded in loading
 144          * the module we have to replay the request. We indicate
 145          * this using -EAGAIN.
 146          */
 147         if (ops) {
 148                 module_put(ops->owner);
 149                 return ERR_PTR(-EAGAIN);
 150         }
 151 #endif
 152         NL_SET_ERR_MSG(extack, "TC classifier not found");
 153         return ERR_PTR(-ENOENT);
 154 }
 155
 156 /* Register(unregister) new classifier type */
 157
 158 int register_tcf_proto_ops(struct tcf_proto_ops *ops)
 159 {
 160         struct tcf_proto_ops *t;
 161         int rc = -EEXIST;
 162
 163         write_lock(&cls_mod_lock);
 164         list_for_each_entry(t, &tcf_proto_base, head)
 165                 if (!strcmp(ops->kind, t->kind))
 166                         goto out;
 167
 168         list_add_tail(&ops->head, &tcf_proto_base);
 169         rc = 0;
 170 out:
 171         write_unlock(&cls_mod_lock);
 172         return rc;
 173 }
 174 EXPORT_SYMBOL(register_tcf_proto_ops);
 175
 176 static struct workqueue_struct *tc_filter_wq;
 177
 178 int unregister_tcf_proto_ops(struct tcf_proto_ops *ops)
 179 {
 180         struct tcf_proto_ops *t;
 181         int rc = -ENOENT;
 182
 183         /* Wait for outstanding call_rcu()s, if any, from a
 184          * tcf_proto_ops's destroy() handler.
 185          */
 186         rcu_barrier();
 187         flush_workqueue(tc_filter_wq);
 188
 189         write_lock(&cls_mod_lock);
 190         list_for_each_entry(t, &tcf_proto_base, head) {
 191                 if (t == ops) {
 192                         list_del(&t->head);
 193                         rc = 0;
 194                         break;
 195                 }
 196         }
 197         write_unlock(&cls_mod_lock);
 198         return rc;
 199 }
 200 EXPORT_SYMBOL(unregister_tcf_proto_ops);
 201
 202 bool tcf_queue_work(struct rcu_work *rwork, work_func_t func)
 203 {
 204         INIT_RCU_WORK(rwork, func);
 205         return queue_rcu_work(tc_filter_wq, rwork);
 206 }
 207 EXPORT_SYMBOL(tcf_queue_work);
 208
 209 /* Select new prio value from the range, managed by kernel. */
 210
 211 static inline u32 tcf_auto_prio(struct tcf_proto *tp)
 212 {
 213         u32 first = TC_H_MAKE(0xC0000000U, 0U);
 214
 215         if (tp)
 216                 first = tp->prio - 1;
 217
 218         return TC_H_MAJ(first);
 219 }
 220
 221 static bool tcf_proto_check_kind(struct nlattr *kind, char *name)
 222 {
 223         if (kind)
 224                 return nla_strlcpy(name, kind, IFNAMSIZ) >= IFNAMSIZ;
 225         memset(name, 0, IFNAMSIZ);
 226         return false;
 227 }
 228
 229 static bool tcf_proto_is_unlocked(const char *kind)
 230 {
 231         const struct tcf_proto_ops *ops;
 232         bool ret;
 233
 234         if (strlen(kind) == 0)
 235                 return false;
 236
 237         ops = tcf_proto_lookup_ops(kind, false, NULL);
 238         /* On error return false to take rtnl lock. Proto lookup/create
 239          * functions will perform lookup again and properly handle errors.
 240          */
 241         if (IS_ERR(ops))
 242                 return false;
 243
 244         ret = !!(ops->flags & TCF_PROTO_OPS_DOIT_UNLOCKED);
 245         module_put(ops->owner);
 246         return ret;
 247 }
 248
 249 static struct tcf_proto *tcf_proto_create(const char *kind, u32 protocol,
 250                                           u32 prio, struct tcf_chain *chain,
 251                                           bool rtnl_held,
 252                                           struct netlink_ext_ack *extack)
 253 {
 254         struct tcf_proto *tp;
 255         int err;
 256
 257         tp = kzalloc(sizeof(*tp), GFP_KERNEL);
 258         if (!tp)
 259                 return ERR_PTR(-ENOBUFS);
 260
 261         tp->ops = tcf_proto_lookup_ops(kind, rtnl_held, extack);
 262         if (IS_ERR(tp->ops)) {
 263                 err = PTR_ERR(tp->ops);
 264                 goto errout;
 265         }
 266         tp->classify = tp->ops->classify;
 267         tp->protocol = protocol;
 268         tp->prio = prio;
 269         tp->chain = chain;
 270         spin_lock_init(&tp->lock);
 271         refcount_set(&tp->refcnt, 1);
 272
 273         err = tp->ops->init(tp);
 274         if (err) {
 275                 module_put(tp->ops->owner);
 276                 goto errout;
 277         }
 278         return tp;
 279
 280 errout:
 281         kfree(tp);
 282         return ERR_PTR(err);
 283 }
 284
 285 static void tcf_proto_get(struct tcf_proto *tp)
 286 {
 287         refcount_inc(&tp->refcnt);
 288 }
 289
 290 static void tcf_chain_put(struct tcf_chain *chain);
 291
 292 static void tcf_proto_destroy(struct tcf_proto *tp, bool rtnl_held,
 293                               bool sig_destroy, struct netlink_ext_ack *extack)
 294 {
 295         tp->ops->destroy(tp, rtnl_held, extack);
 296         if (sig_destroy)
 297                 tcf_proto_signal_destroyed(tp->chain, tp);
 298         tcf_chain_put(tp->chain);
 299         module_put(tp->ops->owner);
 300         kfree_rcu(tp, rcu);
 301 }
 302
 303 static void tcf_proto_put(struct tcf_proto *tp, bool rtnl_held,
 304                           struct netlink_ext_ack *extack)
 305 {
 306         if (refcount_dec_and_test(&tp->refcnt))
 307                 tcf_proto_destroy(tp, rtnl_held, true, extack);
 308 }
 309
 310 static bool tcf_proto_check_delete(struct tcf_proto *tp)
 311 {
 312         if (tp->ops->delete_empty)
 313                 return tp->ops->delete_empty(tp);
 314
 315         tp->deleting = true;
 316         return tp->deleting;
 317 }
 318
 319 static void tcf_proto_mark_delete(struct tcf_proto *tp)
 320 {
 321         spin_lock(&tp->lock);
 322         tp->deleting = true;
 323         spin_unlock(&tp->lock);
 324 }
 325
 326 static bool tcf_proto_is_deleting(struct tcf_proto *tp)
 327 {
 328         bool deleting;
 329
 330         spin_lock(&tp->lock);
 331         deleting = tp->deleting;
 332         spin_unlock(&tp->lock);
 333
 334         return deleting;
 335 }
 336
 337 #define ASSERT_BLOCK_LOCKED(block)                                      \
 338         lockdep_assert_held(&(block)->lock)
 339
 340 struct tcf_filter_chain_list_item {
 341         struct list_head list;
 342         tcf_chain_head_change_t *chain_head_change;
 343         void *chain_head_change_priv;
 344 };
 345
 346 static struct tcf_chain *tcf_chain_create(struct tcf_block *block,
 347                                           u32 chain_index)
 348 {
 349         struct tcf_chain *chain;
 350
 351         ASSERT_BLOCK_LOCKED(block);
 352
 353         chain = kzalloc(sizeof(*chain), GFP_KERNEL);
 354         if (!chain)
 355                 return NULL;
 356         list_add_tail_rcu(&chain->list, &block->chain_list);
 357         mutex_init(&chain->filter_chain_lock);
 358         chain->block = block;
 359         chain->index = chain_index;
 360         chain->refcnt = 1;
 361         if (!chain->index)
 362                 block->chain0.chain = chain;
 363         return chain;
 364 }
 365
 366 static void tcf_chain_head_change_item(struct tcf_filter_chain_list_item *item,
 367                                        struct tcf_proto *tp_head)
 368 {
 369         if (item->chain_head_change)
 370                 item->chain_head_change(tp_head, item->chain_head_change_priv);
 371 }
 372
 373 static void tcf_chain0_head_change(struct tcf_chain *chain,
 374                                    struct tcf_proto *tp_head)
 375 {
 376         struct tcf_filter_chain_list_item *item;
 377         struct tcf_block *block = chain->block;
 378
 379         if (chain->index)
 380                 return;
 381
 382         mutex_lock(&block->lock);
 383         list_for_each_entry(item, &block->chain0.filter_chain_list, list)
 384                 tcf_chain_head_change_item(item, tp_head);
 385         mutex_unlock(&block->lock);
 386 }
 387
 388 /* Returns true if block can be safely freed. */
 389
 390 static bool tcf_chain_detach(struct tcf_chain *chain)
 391 {
 392         struct tcf_block *block = chain->block;
 393
 394         ASSERT_BLOCK_LOCKED(block);
 395
 396         list_del_rcu(&chain->list);
 397         if (!chain->index)
 398                 block->chain0.chain = NULL;
 399
 400         if (list_empty(&block->chain_list) &&
 401             refcount_read(&block->refcnt) == 0)
 402                 return true;
 403
 404         return false;
 405 }
 406
 407 static void tcf_block_destroy(struct tcf_block *block)
 408 {
 409         mutex_destroy(&block->lock);
 410         mutex_destroy(&block->proto_destroy_lock);
 411         kfree_rcu(block, rcu);
 412 }
 413
 414 static void tcf_chain_destroy(struct tcf_chain *chain, bool free_block)
 415 {
 416         struct tcf_block *block = chain->block;
 417
 418         mutex_destroy(&chain->filter_chain_lock);
 419         kfree_rcu(chain, rcu);
 420         if (free_block)
 421                 tcf_block_destroy(block);
 422 }
 423
 424 static void tcf_chain_hold(struct tcf_chain *chain)
 425 {
 426         ASSERT_BLOCK_LOCKED(chain->block);
 427
 428         ++chain->refcnt;
 429 }
 430
 431 static bool tcf_chain_held_by_acts_only(struct tcf_chain *chain)
 432 {
 433         ASSERT_BLOCK_LOCKED(chain->block);
 434
 435         /* In case all the references are action references, this
 436          * chain should not be shown to the user.
 437          */
 438         return chain->refcnt == chain->action_refcnt;
 439 }
 440
 441 static struct tcf_chain *tcf_chain_lookup(struct tcf_block *block,
 442                                           u32 chain_index)
 443 {
 444         struct tcf_chain *chain;
 445
 446         ASSERT_BLOCK_LOCKED(block);
 447
 448         list_for_each_entry(chain, &block->chain_list, list) {
 449                 if (chain->index == chain_index)
 450                         return chain;
 451         }
 452         return NULL;
 453 }
 454
 455 #if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
 456 static struct tcf_chain *tcf_chain_lookup_rcu(const struct tcf_block *block,
 457                                               u32 chain_index)
 458 {
 459         struct tcf_chain *chain;
 460
 461         list_for_each_entry_rcu(chain, &block->chain_list, list) {
 462                 if (chain->index == chain_index)
 463                         return chain;
 464         }
 465         return NULL;
 466 }
 467 #endif
 468
 469 static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb,
 470                            u32 seq, u16 flags, int event, bool unicast);
 471
 472 static struct tcf_chain *__tcf_chain_get(struct tcf_block *block,
 473                                          u32 chain_index, bool create,
 474                                          bool by_act)
 475 {
 476         struct tcf_chain *chain = NULL;
 477         bool is_first_reference;
 478
 479         mutex_lock(&block->lock);
 480         chain = tcf_chain_lookup(block, chain_index);
 481         if (chain) {
 482                 tcf_chain_hold(chain);
 483         } else {
 484                 if (!create)
 485                         goto errout;
 486                 chain = tcf_chain_create(block, chain_index);
 487                 if (!chain)
 488                         goto errout;
 489         }
 490
 491         if (by_act)
 492                 ++chain->action_refcnt;
 493         is_first_reference = chain->refcnt - chain->action_refcnt == 1;
 494         mutex_unlock(&block->lock);
 495
 496         /* Send notification only in case we got the first
 497          * non-action reference. Until then, the chain acts only as
 498          * a placeholder for actions pointing to it and user ought
 499          * not know about them.
 500          */
 501         if (is_first_reference && !by_act)
 502                 tc_chain_notify(chain, NULL, 0, NLM_F_CREATE | NLM_F_EXCL,
 503                                 RTM_NEWCHAIN, false);
 504
 505         return chain;
 506
 507 errout:
 508         mutex_unlock(&block->lock);
 509         return chain;
 510 }
 511
 512 static struct tcf_chain *tcf_chain_get(struct tcf_block *block, u32 chain_index,
 513                                        bool create)
 514 {
 515         return __tcf_chain_get(block, chain_index, create, false);
 516 }
 517
 518 struct tcf_chain *tcf_chain_get_by_act(struct tcf_block *block, u32 chain_index)
 519 {
 520         return __tcf_chain_get(block, chain_index, true, true);
 521 }
 522 EXPORT_SYMBOL(tcf_chain_get_by_act);
 523
 524 static void tc_chain_tmplt_del(const struct tcf_proto_ops *tmplt_ops,
 525                                void *tmplt_priv);
 526 static int tc_chain_notify_delete(const struct tcf_proto_ops *tmplt_ops,
 527                                   void *tmplt_priv, u32 chain_index,
 528                                   struct tcf_block *block, struct sk_buff *oskb,
 529                                   u32 seq, u16 flags, bool unicast);
 530
 531 static void __tcf_chain_put(struct tcf_chain *chain, bool by_act,
 532                             bool explicitly_created)
 533 {
 534         struct tcf_block *block = chain->block;
 535         const struct tcf_proto_ops *tmplt_ops;
 536         unsigned int refcnt, non_act_refcnt;
 537         bool free_block = false;
 538         void *tmplt_priv;
 539
 540         mutex_lock(&block->lock);
 541         if (explicitly_created) {
 542                 if (!chain->explicitly_created) {
 543                         mutex_unlock(&block->lock);
 544                         return;
 545                 }
 546                 chain->explicitly_created = false;
 547         }
 548
 549         if (by_act)
 550                 chain->action_refcnt--;
 551
 552         /* tc_chain_notify_delete can't be called while holding block lock.
 553          * However, when block is unlocked chain can be changed concurrently, so
 554          * save these to temporary variables.
 555          */
 556         refcnt = --chain->refcnt;
 557         non_act_refcnt = refcnt - chain->action_refcnt;
 558         tmplt_ops = chain->tmplt_ops;
 559         tmplt_priv = chain->tmplt_priv;
 560
 561         if (non_act_refcnt == chain->explicitly_created && !by_act) {
 562                 if (non_act_refcnt == 0)
 563                         tc_chain_notify_delete(tmplt_ops, tmplt_priv,
 564                                                chain->index, block, NULL, 0, 0,
 565                                                false);
 566                 /* Last reference to chain, no need to lock. */
 567                 chain->flushing = false;
 568         }
 569
 570         if (refcnt == 0)
 571                 free_block = tcf_chain_detach(chain);
 572         mutex_unlock(&block->lock);
 573
 574         if (refcnt == 0) {
 575                 tc_chain_tmplt_del(tmplt_ops, tmplt_priv);
 576                 tcf_chain_destroy(chain, free_block);
 577         }
 578 }
 579
 580 static void tcf_chain_put(struct tcf_chain *chain)
 581 {
 582         __tcf_chain_put(chain, false, false);
 583 }
 584
 585 void tcf_chain_put_by_act(struct tcf_chain *chain)
 586 {
 587         __tcf_chain_put(chain, true, false);
 588 }
 589 EXPORT_SYMBOL(tcf_chain_put_by_act);
 590
 591 static void tcf_chain_put_explicitly_created(struct tcf_chain *chain)
 592 {
 593         __tcf_chain_put(chain, false, true);
 594 }
 595
 596 static void tcf_chain_flush(struct tcf_chain *chain, bool rtnl_held)
 597 {
 598         struct tcf_proto *tp, *tp_next;
 599
 600         mutex_lock(&chain->filter_chain_lock);
 601         tp = tcf_chain_dereference(chain->filter_chain, chain);
 602         while (tp) {
 603                 tp_next = rcu_dereference_protected(tp->next, 1);
 604                 tcf_proto_signal_destroying(chain, tp);
 605                 tp = tp_next;
 606         }
 607         tp = tcf_chain_dereference(chain->filter_chain, chain);
 608         RCU_INIT_POINTER(chain->filter_chain, NULL);
 609         tcf_chain0_head_change(chain, NULL);
 610         chain->flushing = true;
 611         mutex_unlock(&chain->filter_chain_lock);
 612
 613         while (tp) {
 614                 tp_next = rcu_dereference_protected(tp->next, 1);
 615                 tcf_proto_put(tp, rtnl_held, NULL);
 616                 tp = tp_next;
 617         }
 618 }
 619
 620 static int tcf_block_setup(struct tcf_block *block,
 621                            struct flow_block_offload *bo);
 622
 623 static void tcf_block_offload_init(struct flow_block_offload *bo,
 624                                    struct net_device *dev, struct Qdisc *sch,
 625                                    enum flow_block_command command,
 626                                    enum flow_block_binder_type binder_type,
 627                                    struct flow_block *flow_block,
 628                                    bool shared, struct netlink_ext_ack *extack)
 629 {
 630         bo->net = dev_net(dev);
 631         bo->command = command;
 632         bo->binder_type = binder_type;
 633         bo->block = flow_block;
 634         bo->block_shared = shared;
 635         bo->extack = extack;
 636         bo->sch = sch;
 637         bo->cb_list_head = &flow_block->cb_list;
 638         INIT_LIST_HEAD(&bo->cb_list);
 639 }
 640
 641 static void tcf_block_unbind(struct tcf_block *block,
 642                              struct flow_block_offload *bo);
 643
 644 static void tc_block_indr_cleanup(struct flow_block_cb *block_cb)
 645 {
 646         struct tcf_block *block = block_cb->indr.data;
 647         struct net_device *dev = block_cb->indr.dev;
 648         struct Qdisc *sch = block_cb->indr.sch;
 649         struct netlink_ext_ack extack = {};
 650         struct flow_block_offload bo = {};
 651
 652         tcf_block_offload_init(&bo, dev, sch, FLOW_BLOCK_UNBIND,
 653                                block_cb->indr.binder_type,
 654                                &block->flow_block, tcf_block_shared(block),
 655                                &extack);
 656         rtnl_lock();
 657         down_write(&block->cb_lock);
 658         list_del(&block_cb->driver_list);
 659         list_move(&block_cb->list, &bo.cb_list);
 660         tcf_block_unbind(block, &bo);
 661         up_write(&block->cb_lock);
 662         rtnl_unlock();
 663 }
 664
 665 static bool tcf_block_offload_in_use(struct tcf_block *block)
 666 {
 667         return atomic_read(&block->offloadcnt);
 668 }
 669
 670 static int tcf_block_offload_cmd(struct tcf_block *block,
 671                                  struct net_device *dev, struct Qdisc *sch,
 672                                  struct tcf_block_ext_info *ei,
 673                                  enum flow_block_command command,
 674                                  struct netlink_ext_ack *extack)
 675 {
 676         struct flow_block_offload bo = {};
 677
 678         tcf_block_offload_init(&bo, dev, sch, command, ei->binder_type,
 679                                &block->flow_block, tcf_block_shared(block),
 680                                extack);
 681
 682         if (dev->netdev_ops->ndo_setup_tc) {
 683                 int err;
 684
 685                 err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_BLOCK, &bo);
 686                 if (err < 0) {
 687                         if (err != -EOPNOTSUPP)
 688                                 NL_SET_ERR_MSG(extack, "Driver ndo_setup_tc failed");
 689                         return err;
 690                 }
 691
 692                 return tcf_block_setup(block, &bo);
 693         }
 694
 695         flow_indr_dev_setup_offload(dev, sch, TC_SETUP_BLOCK, block, &bo,
 696                                     tc_block_indr_cleanup);
 697         tcf_block_setup(block, &bo);
 698
 699         return -EOPNOTSUPP;
 700 }
 701
 702 static int tcf_block_offload_bind(struct tcf_block *block, struct Qdisc *q,
 703                                   struct tcf_block_ext_info *ei,
 704                                   struct netlink_ext_ack *extack)
 705 {
 706         struct net_device *dev = q->dev_queue->dev;
 707         int err;
 708
 709         down_write(&block->cb_lock);
 710
 711         /* If tc offload feature is disabled and the block we try to bind
 712          * to already has some offloaded filters, forbid to bind.
 713          */
 714         if (dev->netdev_ops->ndo_setup_tc &&
 715             !tc_can_offload(dev) &&
 716             tcf_block_offload_in_use(block)) {
 717                 NL_SET_ERR_MSG(extack, "Bind to offloaded block failed as dev has offload disabled");
 718                 err = -EOPNOTSUPP;
 719                 goto err_unlock;
 720         }
 721
 722         err = tcf_block_offload_cmd(block, dev, q, ei, FLOW_BLOCK_BIND, extack);
 723         if (err == -EOPNOTSUPP)
 724                 goto no_offload_dev_inc;
 725         if (err)
 726                 goto err_unlock;
 727
 728         up_write(&block->cb_lock);
 729         return 0;
 730
 731 no_offload_dev_inc:
 732         if (tcf_block_offload_in_use(block))
 733                 goto err_unlock;
 734
 735         err = 0;
 736         block->nooffloaddevcnt++;
 737 err_unlock:
 738         up_write(&block->cb_lock);
 739         return err;
 740 }
 741
 742 static void tcf_block_offload_unbind(struct tcf_block *block, struct Qdisc *q,
 743                                      struct tcf_block_ext_info *ei)
 744 {
 745         struct net_device *dev = q->dev_queue->dev;
 746         int err;
 747
 748         down_write(&block->cb_lock);
 749         err = tcf_block_offload_cmd(block, dev, q, ei, FLOW_BLOCK_UNBIND, NULL);
 750         if (err == -EOPNOTSUPP)
 751                 goto no_offload_dev_dec;
 752         up_write(&block->cb_lock);
 753         return;
 754
 755 no_offload_dev_dec:
 756         WARN_ON(block->nooffloaddevcnt-- == 0);
 757         up_write(&block->cb_lock);
 758 }
 759
 760 static int
 761 tcf_chain0_head_change_cb_add(struct tcf_block *block,
 762                               struct tcf_block_ext_info *ei,
 763                               struct netlink_ext_ack *extack)
 764 {
 765         struct tcf_filter_chain_list_item *item;
 766         struct tcf_chain *chain0;
 767
 768         item = kmalloc(sizeof(*item), GFP_KERNEL);
 769         if (!item) {
 770                 NL_SET_ERR_MSG(extack, "Memory allocation for head change callback item failed");
 771                 return -ENOMEM;
 772         }
 773         item->chain_head_change = ei->chain_head_change;
 774         item->chain_head_change_priv = ei->chain_head_change_priv;
 775
 776         mutex_lock(&block->lock);
 777         chain0 = block->chain0.chain;
 778         if (chain0)
 779                 tcf_chain_hold(chain0);
 780         else
 781                 list_add(&item->list, &block->chain0.filter_chain_list);
 782         mutex_unlock(&block->lock);
 783
 784         if (chain0) {
 785                 struct tcf_proto *tp_head;
 786
 787                 mutex_lock(&chain0->filter_chain_lock);
 788
 789                 tp_head = tcf_chain_dereference(chain0->filter_chain, chain0);
 790                 if (tp_head)
 791                         tcf_chain_head_change_item(item, tp_head);
 792
 793                 mutex_lock(&block->lock);
 794                 list_add(&item->list, &block->chain0.filter_chain_list);
 795                 mutex_unlock(&block->lock);
 796
 797                 mutex_unlock(&chain0->filter_chain_lock);
 798                 tcf_chain_put(chain0);
 799         }
 800
 801         return 0;
 802 }
 803
 804 static void
 805 tcf_chain0_head_change_cb_del(struct tcf_block *block,
 806                               struct tcf_block_ext_info *ei)
 807 {
 808         struct tcf_filter_chain_list_item *item;
 809
 810         mutex_lock(&block->lock);
 811         list_for_each_entry(item, &block->chain0.filter_chain_list, list) {
 812                 if ((!ei->chain_head_change && !ei->chain_head_change_priv) ||
 813                     (item->chain_head_change == ei->chain_head_change &&
 814                      item->chain_head_change_priv == ei->chain_head_change_priv)) {
 815                         if (block->chain0.chain)
 816                                 tcf_chain_head_change_item(item, NULL);
 817                         list_del(&item->list);
 818                         mutex_unlock(&block->lock);
 819
 820                         kfree(item);
 821                         return;
 822                 }
 823         }
 824         mutex_unlock(&block->lock);
 825         WARN_ON(1);
 826 }
 827
 828 struct tcf_net {
 829         spinlock_t idr_lock; /* Protects idr */
 830         struct idr idr;
 831 };
 832
 833 static unsigned int tcf_net_id;
 834
 835 static int tcf_block_insert(struct tcf_block *block, struct net *net,
 836                             struct netlink_ext_ack *extack)
 837 {
 838         struct tcf_net *tn = net_generic(net, tcf_net_id);
 839         int err;
 840
 841         idr_preload(GFP_KERNEL);
 842         spin_lock(&tn->idr_lock);
 843         err = idr_alloc_u32(&tn->idr, block, &block->index, block->index,
 844                             GFP_NOWAIT);
 845         spin_unlock(&tn->idr_lock);
 846         idr_preload_end();
 847
 848         return err;
 849 }
 850
 851 static void tcf_block_remove(struct tcf_block *block, struct net *net)
 852 {
 853         struct tcf_net *tn = net_generic(net, tcf_net_id);
 854
 855         spin_lock(&tn->idr_lock);
 856         idr_remove(&tn->idr, block->index);
 857         spin_unlock(&tn->idr_lock);
 858 }
 859
 860 static struct tcf_block *tcf_block_create(struct net *net, struct Qdisc *q,
 861                                           u32 block_index,
 862                                           struct netlink_ext_ack *extack)
 863 {
 864         struct tcf_block *block;
 865
 866         block = kzalloc(sizeof(*block), GFP_KERNEL);
 867         if (!block) {
 868                 NL_SET_ERR_MSG(extack, "Memory allocation for block failed");
 869                 return ERR_PTR(-ENOMEM);
 870         }
 871         mutex_init(&block->lock);
 872         mutex_init(&block->proto_destroy_lock);
 873         init_rwsem(&block->cb_lock);
 874         flow_block_init(&block->flow_block);
 875         INIT_LIST_HEAD(&block->chain_list);
 876         INIT_LIST_HEAD(&block->owner_list);
 877         INIT_LIST_HEAD(&block->chain0.filter_chain_list);
 878
 879         refcount_set(&block->refcnt, 1);
 880         block->net = net;
 881         block->index = block_index;
 882
 883         /* Don't store q pointer for blocks which are shared */
 884         if (!tcf_block_shared(block))
 885                 block->q = q;
 886         return block;
 887 }
 888
 889 static struct tcf_block *tcf_block_lookup(struct net *net, u32 block_index)
 890 {
 891         struct tcf_net *tn = net_generic(net, tcf_net_id);
 892
 893         return idr_find(&tn->idr, block_index);
 894 }
 895
 896 static struct tcf_block *tcf_block_refcnt_get(struct net *net, u32 block_index)
 897 {
 898         struct tcf_block *block;
 899
 900         rcu_read_lock();
 901         block = tcf_block_lookup(net, block_index);
 902         if (block && !refcount_inc_not_zero(&block->refcnt))
 903                 block = NULL;
 904         rcu_read_unlock();
 905
 906         return block;
 907 }
 908
 909 static struct tcf_chain *
 910 __tcf_get_next_chain(struct tcf_block *block, struct tcf_chain *chain)
 911 {
 912         mutex_lock(&block->lock);
 913         if (chain)
 914                 chain = list_is_last(&chain->list, &block->chain_list) ?
 915                         NULL : list_next_entry(chain, list);
 916         else
 917                 chain = list_first_entry_or_null(&block->chain_list,
 918                                                  struct tcf_chain, list);
 919
 920         /* skip all action-only chains */
 921         while (chain && tcf_chain_held_by_acts_only(chain))
 922                 chain = list_is_last(&chain->list, &block->chain_list) ?
 923                         NULL : list_next_entry(chain, list);
 924
 925         if (chain)
 926                 tcf_chain_hold(chain);
 927         mutex_unlock(&block->lock);
 928
 929         return chain;
 930 }
 931
 932 /* Function to be used by all clients that want to iterate over all chains on
 933  * block. It properly obtains block->lock and takes reference to chain before
 934  * returning it. Users of this function must be tolerant to concurrent chain
 935  * insertion/deletion or ensure that no concurrent chain modification is
 936  * possible. Note that all netlink dump callbacks cannot guarantee to provide
 937  * consistent dump because rtnl lock is released each time skb is filled with
 938  * data and sent to user-space.
 939  */
 940
 941 struct tcf_chain *
 942 tcf_get_next_chain(struct tcf_block *block, struct tcf_chain *chain)
 943 {
 944         struct tcf_chain *chain_next = __tcf_get_next_chain(block, chain);
 945
 946         if (chain)
 947                 tcf_chain_put(chain);
 948
 949         return chain_next;
 950 }
 951 EXPORT_SYMBOL(tcf_get_next_chain);
 952
 953 static struct tcf_proto *
 954 __tcf_get_next_proto(struct tcf_chain *chain, struct tcf_proto *tp)
 955 {
 956         u32 prio = 0;
 957
 958         ASSERT_RTNL();
 959         mutex_lock(&chain->filter_chain_lock);
 960
 961         if (!tp) {
 962                 tp = tcf_chain_dereference(chain->filter_chain, chain);
 963         } else if (tcf_proto_is_deleting(tp)) {
 964                 /* 'deleting' flag is set and chain->filter_chain_lock was
 965                  * unlocked, which means next pointer could be invalid. Restart
 966                  * search.
 967                  */
 968                 prio = tp->prio + 1;
 969                 tp = tcf_chain_dereference(chain->filter_chain, chain);
 970
 971                 for (; tp; tp = tcf_chain_dereference(tp->next, chain))
 972                         if (!tp->deleting && tp->prio >= prio)
 973                                 break;
 974         } else {
 975                 tp = tcf_chain_dereference(tp->next, chain);
 976         }
 977
 978         if (tp)
 979                 tcf_proto_get(tp);
 980
 981         mutex_unlock(&chain->filter_chain_lock);
 982
 983         return tp;
 984 }
 985
 986 /* Function to be used by all clients that want to iterate over all tp's on
 987  * chain. Users of this function must be tolerant to concurrent tp
 988  * insertion/deletion or ensure that no concurrent chain modification is
 989  * possible. Note that all netlink dump callbacks cannot guarantee to provide
 990  * consistent dump because rtnl lock is released each time skb is filled with
 991  * data and sent to user-space.
 992  */
 993
 994 struct tcf_proto *
 995 tcf_get_next_proto(struct tcf_chain *chain, struct tcf_proto *tp,
 996                    bool rtnl_held)
 997 {
 998         struct tcf_proto *tp_next = __tcf_get_next_proto(chain, tp);
 999
1000         if (tp)
1001                 tcf_proto_put(tp, rtnl_held, NULL);
1002
1003         return tp_next;
1004 }
1005 EXPORT_SYMBOL(tcf_get_next_proto);
1006
1007 static void tcf_block_flush_all_chains(struct tcf_block *block, bool rtnl_held)
1008 {
1009         struct tcf_chain *chain;
1010
1011         /* Last reference to block. At this point chains cannot be added or
1012          * removed concurrently.
1013          */
1014         for (chain = tcf_get_next_chain(block, NULL);
1015              chain;
1016              chain = tcf_get_next_chain(block, chain)) {
1017                 tcf_chain_put_explicitly_created(chain);
1018                 tcf_chain_flush(chain, rtnl_held);
1019         }
1020 }
1021
1022 /* Lookup Qdisc and increments its reference counter.
1023  * Set parent, if necessary.
1024  */
1025
1026 static int __tcf_qdisc_find(struct net *net, struct Qdisc **q,
1027                             u32 *parent, int ifindex, bool rtnl_held,
1028                             struct netlink_ext_ack *extack)
1029 {
1030         const struct Qdisc_class_ops *cops;
1031         struct net_device *dev;
1032         int err = 0;
1033
1034         if (ifindex == TCM_IFINDEX_MAGIC_BLOCK)
1035                 return 0;
1036
1037         rcu_read_lock();
1038
1039         /* Find link */
1040         dev = dev_get_by_index_rcu(net, ifindex);
1041         if (!dev) {
1042                 rcu_read_unlock();
1043                 return -ENODEV;
1044         }
1045
1046         /* Find qdisc */
1047         if (!*parent) {
1048                 *q = rcu_dereference(dev->qdisc);
1049                 *parent = (*q)->handle;
1050         } else {
1051                 *q = qdisc_lookup_rcu(dev, TC_H_MAJ(*parent));
1052                 if (!*q) {
1053                         NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists");
1054                         err = -EINVAL;
1055                         goto errout_rcu;
1056                 }
1057         }
1058
1059         *q = qdisc_refcount_inc_nz(*q);
1060         if (!*q) {
1061                 NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists");
1062                 err = -EINVAL;
1063                 goto errout_rcu;
1064         }
1065
1066         /* Is it classful? */
1067         cops = (*q)->ops->cl_ops;
1068         if (!cops) {
1069                 NL_SET_ERR_MSG(extack, "Qdisc not classful");
1070                 err = -EINVAL;
1071                 goto errout_qdisc;
1072         }
1073
1074         if (!cops->tcf_block) {
1075                 NL_SET_ERR_MSG(extack, "Class doesn't support blocks");
1076                 err = -EOPNOTSUPP;
1077                 goto errout_qdisc;
1078         }
1079
1080 errout_rcu:
1081         /* At this point we know that qdisc is not noop_qdisc,
1082          * which means that qdisc holds a reference to net_device
1083          * and we hold a reference to qdisc, so it is safe to release
1084          * rcu read lock.
1085          */
1086         rcu_read_unlock();
1087         return err;
1088
1089 errout_qdisc:
1090         rcu_read_unlock();
1091
1092         if (rtnl_held)
1093                 qdisc_put(*q);
1094         else
1095                 qdisc_put_unlocked(*q);
1096         *q = NULL;
1097
1098         return err;
1099 }
1100
1101 static int __tcf_qdisc_cl_find(struct Qdisc *q, u32 parent, unsigned long *cl,
1102                                int ifindex, struct netlink_ext_ack *extack)
1103 {
1104         if (ifindex == TCM_IFINDEX_MAGIC_BLOCK)
1105                 return 0;
1106
1107         /* Do we search for filter, attached to class? */
1108         if (TC_H_MIN(parent)) {
1109                 const struct Qdisc_class_ops *cops = q->ops->cl_ops;
1110
1111                 *cl = cops->find(q, parent);
1112                 if (*cl == 0) {
1113                         NL_SET_ERR_MSG(extack, "Specified class doesn't exist");
1114                         return -ENOENT;
1115                 }
1116         }
1117
1118         return 0;
1119 }
1120
1121 static struct tcf_block *__tcf_block_find(struct net *net, struct Qdisc *q,
1122                                           unsigned long cl, int ifindex,
1123                                           u32 block_index,
1124                                           struct netlink_ext_ack *extack)
1125 {
1126         struct tcf_block *block;
1127
1128         if (ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
1129                 block = tcf_block_refcnt_get(net, block_index);
1130                 if (!block) {
1131                         NL_SET_ERR_MSG(extack, "Block of given index was not found");
1132                         return ERR_PTR(-EINVAL);
1133                 }
1134         } else {
1135                 const struct Qdisc_class_ops *cops = q->ops->cl_ops;
1136
1137                 block = cops->tcf_block(q, cl, extack);
1138                 if (!block)
1139                         return ERR_PTR(-EINVAL);
1140
1141                 if (tcf_block_shared(block)) {
1142                         NL_SET_ERR_MSG(extack, "This filter block is shared. Please use the block index to manipulate the filters");
1143                         return ERR_PTR(-EOPNOTSUPP);
1144                 }
1145
1146                 /* Always take reference to block in order to support execution
1147                  * of rules update path of cls API without rtnl lock. Caller
1148                  * must release block when it is finished using it. 'if' block
1149                  * of this conditional obtain reference to block by calling
1150                  * tcf_block_refcnt_get().
1151                  */
1152                 refcount_inc(&block->refcnt);
1153         }
1154
1155         return block;
1156 }
1157
1158 static void __tcf_block_put(struct tcf_block *block, struct Qdisc *q,
1159                             struct tcf_block_ext_info *ei, bool rtnl_held)
1160 {
1161         if (refcount_dec_and_mutex_lock(&block->refcnt, &block->lock)) {
1162                 /* Flushing/putting all chains will cause the block to be
1163                  * deallocated when last chain is freed. However, if chain_list
1164                  * is empty, block has to be manually deallocated. After block
1165                  * reference counter reached 0, it is no longer possible to
1166                  * increment it or add new chains to block.
1167                  */
1168                 bool free_block = list_empty(&block->chain_list);
1169
1170                 mutex_unlock(&block->lock);
1171                 if (tcf_block_shared(block))
1172                         tcf_block_remove(block, block->net);
1173
1174                 if (q)
1175                         tcf_block_offload_unbind(block, q, ei);
1176
1177                 if (free_block)
1178                         tcf_block_destroy(block);
1179                 else
1180                         tcf_block_flush_all_chains(block, rtnl_held);
1181         } else if (q) {
1182                 tcf_block_offload_unbind(block, q, ei);
1183         }
1184 }
1185
1186 static void tcf_block_refcnt_put(struct tcf_block *block, bool rtnl_held)
1187 {
1188         __tcf_block_put(block, NULL, NULL, rtnl_held);
1189 }
1190
1191 /* Find tcf block.
1192  * Set q, parent, cl when appropriate.
1193  */
1194
1195 static struct tcf_block *tcf_block_find(struct net *net, struct Qdisc **q,
1196                                         u32 *parent, unsigned long *cl,
1197                                         int ifindex, u32 block_index,
1198                                         struct netlink_ext_ack *extack)
1199 {
1200         struct tcf_block *block;
1201         int err = 0;
1202
1203         ASSERT_RTNL();
1204
1205         err = __tcf_qdisc_find(net, q, parent, ifindex, true, extack);
1206         if (err)
1207                 goto errout;
1208
1209         err = __tcf_qdisc_cl_find(*q, *parent, cl, ifindex, extack);
1210         if (err)
1211                 goto errout_qdisc;
1212
1213         block = __tcf_block_find(net, *q, *cl, ifindex, block_index, extack);
1214         if (IS_ERR(block)) {
1215                 err = PTR_ERR(block);
1216                 goto errout_qdisc;
1217         }
1218
1219         return block;
1220
1221 errout_qdisc:
1222         if (*q)
1223                 qdisc_put(*q);
1224 errout:
1225         *q = NULL;
1226         return ERR_PTR(err);
1227 }
1228
1229 static void tcf_block_release(struct Qdisc *q, struct tcf_block *block,
1230                               bool rtnl_held)
1231 {
1232         if (!IS_ERR_OR_NULL(block))
1233                 tcf_block_refcnt_put(block, rtnl_held);
1234
1235         if (q) {
1236                 if (rtnl_held)
1237                         qdisc_put(q);
1238                 else
1239                         qdisc_put_unlocked(q);
1240         }
1241 }
1242
1243 struct tcf_block_owner_item {
1244         struct list_head list;
1245         struct Qdisc *q;
1246         enum flow_block_binder_type binder_type;
1247 };
1248
1249 static void
1250 tcf_block_owner_netif_keep_dst(struct tcf_block *block,
1251                                struct Qdisc *q,
1252                                enum flow_block_binder_type binder_type)
1253 {
1254         if (block->keep_dst &&
1255             binder_type != FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS &&
1256             binder_type != FLOW_BLOCK_BINDER_TYPE_CLSACT_EGRESS)
1257                 netif_keep_dst(qdisc_dev(q));
1258 }
1259
1260 void tcf_block_netif_keep_dst(struct tcf_block *block)
1261 {
1262         struct tcf_block_owner_item *item;
1263
1264         block->keep_dst = true;
1265         list_for_each_entry(item, &block->owner_list, list)
1266                 tcf_block_owner_netif_keep_dst(block, item->q,
1267                                                item->binder_type);
1268 }
1269 EXPORT_SYMBOL(tcf_block_netif_keep_dst);
1270
1271 static int tcf_block_owner_add(struct tcf_block *block,
1272                                struct Qdisc *q,
1273                                enum flow_block_binder_type binder_type)
1274 {
1275         struct tcf_block_owner_item *item;
1276
1277         item = kmalloc(sizeof(*item), GFP_KERNEL);
1278         if (!item)
1279                 return -ENOMEM;
1280         item->q = q;
1281         item->binder_type = binder_type;
1282         list_add(&item->list, &block->owner_list);
1283         return 0;
1284 }
1285
1286 static void tcf_block_owner_del(struct tcf_block *block,
1287                                 struct Qdisc *q,
1288                                 enum flow_block_binder_type binder_type)
1289 {
1290         struct tcf_block_owner_item *item;
1291
1292         list_for_each_entry(item, &block->owner_list, list) {
1293                 if (item->q == q && item->binder_type == binder_type) {
1294                         list_del(&item->list);
1295                         kfree(item);
1296                         return;
1297                 }
1298         }
1299         WARN_ON(1);
1300 }
1301
1302 int tcf_block_get_ext(struct tcf_block **p_block, struct Qdisc *q,
1303                       struct tcf_block_ext_info *ei,
1304                       struct netlink_ext_ack *extack)
1305 {
1306         struct net *net = qdisc_net(q);
1307         struct tcf_block *block = NULL;
1308         int err;
1309
1310         if (ei->block_index)
1311                 /* block_index not 0 means the shared block is requested */
1312                 block = tcf_block_refcnt_get(net, ei->block_index);
1313
1314         if (!block) {
1315                 block = tcf_block_create(net, q, ei->block_index, extack);
1316                 if (IS_ERR(block))
1317                         return PTR_ERR(block);
1318                 if (tcf_block_shared(block)) {
1319                         err = tcf_block_insert(block, net, extack);
1320                         if (err)
1321                                 goto err_block_insert;
1322                 }
1323         }
1324
1325         err = tcf_block_owner_add(block, q, ei->binder_type);
1326         if (err)
1327                 goto err_block_owner_add;
1328
1329         tcf_block_owner_netif_keep_dst(block, q, ei->binder_type);
1330
1331         err = tcf_chain0_head_change_cb_add(block, ei, extack);
1332         if (err)
1333                 goto err_chain0_head_change_cb_add;
1334
1335         err = tcf_block_offload_bind(block, q, ei, extack);
1336         if (err)
1337                 goto err_block_offload_bind;
1338
1339         *p_block = block;
1340         return 0;
1341
1342 err_block_offload_bind:
1343         tcf_chain0_head_change_cb_del(block, ei);
1344 err_chain0_head_change_cb_add:
1345         tcf_block_owner_del(block, q, ei->binder_type);
1346 err_block_owner_add:
1347 err_block_insert:
1348         tcf_block_refcnt_put(block, true);
1349         return err;
1350 }
1351 EXPORT_SYMBOL(tcf_block_get_ext);
1352
1353 static void tcf_chain_head_change_dflt(struct tcf_proto *tp_head, void *priv)
1354 {
1355         struct tcf_proto __rcu **p_filter_chain = priv;
1356
1357         rcu_assign_pointer(*p_filter_chain, tp_head);
1358 }
1359
1360 int tcf_block_get(struct tcf_block **p_block,
1361                   struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q,
1362                   struct netlink_ext_ack *extack)
1363 {
1364         struct tcf_block_ext_info ei = {
1365                 .chain_head_change = tcf_chain_head_change_dflt,
1366                 .chain_head_change_priv = p_filter_chain,
1367         };
1368
1369         WARN_ON(!p_filter_chain);
1370         return tcf_block_get_ext(p_block, q, &ei, extack);
1371 }
1372 EXPORT_SYMBOL(tcf_block_get);
1373
1374 /* XXX: Standalone actions are not allowed to jump to any chain, and bound
1375  * actions should be all removed after flushing.
1376  */
1377 void tcf_block_put_ext(struct tcf_block *block, struct Qdisc *q,
1378                        struct tcf_block_ext_info *ei)
1379 {
1380         if (!block)
1381                 return;
1382         tcf_chain0_head_change_cb_del(block, ei);
1383         tcf_block_owner_del(block, q, ei->binder_type);
1384
1385         __tcf_block_put(block, q, ei, true);
1386 }
1387 EXPORT_SYMBOL(tcf_block_put_ext);
1388
1389 void tcf_block_put(struct tcf_block *block)
1390 {
1391         struct tcf_block_ext_info ei = {0, };
1392
1393         if (!block)
1394                 return;
1395         tcf_block_put_ext(block, block->q, &ei);
1396 }
1397
1398 EXPORT_SYMBOL(tcf_block_put);
1399
1400 static int
1401 tcf_block_playback_offloads(struct tcf_block *block, flow_setup_cb_t *cb,
1402                             void *cb_priv, bool add, bool offload_in_use,
1403                             struct netlink_ext_ack *extack)
1404 {
1405         struct tcf_chain *chain, *chain_prev;
1406         struct tcf_proto *tp, *tp_prev;
1407         int err;
1408
1409         lockdep_assert_held(&block->cb_lock);
1410
1411         for (chain = __tcf_get_next_chain(block, NULL);
1412              chain;
1413              chain_prev = chain,
1414                      chain = __tcf_get_next_chain(block, chain),
1415                      tcf_chain_put(chain_prev)) {
1416                 for (tp = __tcf_get_next_proto(chain, NULL); tp;
1417                      tp_prev = tp,
1418                              tp = __tcf_get_next_proto(chain, tp),
1419                              tcf_proto_put(tp_prev, true, NULL)) {
1420                         if (tp->ops->reoffload) {
1421                                 err = tp->ops->reoffload(tp, add, cb, cb_priv,
1422                                                          extack);
1423                                 if (err && add)
1424                                         goto err_playback_remove;
1425                         } else if (add && offload_in_use) {
1426                                 err = -EOPNOTSUPP;
1427                                 NL_SET_ERR_MSG(extack, "Filter HW offload failed - classifier without re-offloading support");
1428                                 goto err_playback_remove;
1429                         }
1430                 }
1431         }
1432
1433         return 0;
1434
1435 err_playback_remove:
1436         tcf_proto_put(tp, true, NULL);
1437         tcf_chain_put(chain);
1438         tcf_block_playback_offloads(block, cb, cb_priv, false, offload_in_use,
1439                                     extack);
1440         return err;
1441 }
1442
1443 static int tcf_block_bind(struct tcf_block *block,
1444                           struct flow_block_offload *bo)
1445 {
1446         struct flow_block_cb *block_cb, *next;
1447         int err, i = 0;
1448
1449         lockdep_assert_held(&block->cb_lock);
1450
1451         list_for_each_entry(block_cb, &bo->cb_list, list) {
1452                 err = tcf_block_playback_offloads(block, block_cb->cb,
1453                                                   block_cb->cb_priv, true,
1454                                                   tcf_block_offload_in_use(block),
1455                                                   bo->extack);
1456                 if (err)
1457                         goto err_unroll;
1458                 if (!bo->unlocked_driver_cb)
1459                         block->lockeddevcnt++;
1460
1461                 i++;
1462         }
1463         list_splice(&bo->cb_list, &block->flow_block.cb_list);
1464
1465         return 0;
1466
1467 err_unroll:
1468         list_for_each_entry_safe(block_cb, next, &bo->cb_list, list) {
1469                 list_del(&block_cb->driver_list);
1470                 if (i-- > 0) {
1471                         list_del(&block_cb->list);
1472                         tcf_block_playback_offloads(block, block_cb->cb,
1473                                                     block_cb->cb_priv, false,
1474                                                     tcf_block_offload_in_use(block),
1475                                                     NULL);
1476                         if (!bo->unlocked_driver_cb)
1477                                 block->lockeddevcnt--;
1478                 }
1479                 flow_block_cb_free(block_cb);
1480         }
1481
1482         return err;
1483 }
1484
1485 static void tcf_block_unbind(struct tcf_block *block,
1486                              struct flow_block_offload *bo)
1487 {
1488         struct flow_block_cb *block_cb, *next;
1489
1490         lockdep_assert_held(&block->cb_lock);
1491
1492         list_for_each_entry_safe(block_cb, next, &bo->cb_list, list) {
1493                 tcf_block_playback_offloads(block, block_cb->cb,
1494                                             block_cb->cb_priv, false,
1495                                             tcf_block_offload_in_use(block),
1496                                             NULL);
1497                 list_del(&block_cb->list);
1498                 flow_block_cb_free(block_cb);
1499                 if (!bo->unlocked_driver_cb)
1500                         block->lockeddevcnt--;
1501         }
1502 }
1503
1504 static int tcf_block_setup(struct tcf_block *block,
1505                            struct flow_block_offload *bo)
1506 {
1507         int err;
1508
1509         switch (bo->command) {
1510         case FLOW_BLOCK_BIND:
1511                 err = tcf_block_bind(block, bo);
1512                 break;
1513         case FLOW_BLOCK_UNBIND:
1514                 err = 0;
1515                 tcf_block_unbind(block, bo);
1516                 break;
1517         default:
1518                 WARN_ON_ONCE(1);
1519                 err = -EOPNOTSUPP;
1520         }
1521
1522         return err;
1523 }
1524
1525 /* Main classifier routine: scans classifier chain attached
1526  * to this qdisc, (optionally) tests for protocol and asks
1527  * specific classifiers.
1528  */
1529 static inline int __tcf_classify(struct sk_buff *skb,
1530                                  const struct tcf_proto *tp,
1531                                  const struct tcf_proto *orig_tp,
1532                                  struct tcf_result *res,
1533                                  bool compat_mode,
1534                                  u32 *last_executed_chain)
1535 {
1536 #ifdef CONFIG_NET_CLS_ACT
1537         const int max_reclassify_loop = 16;
1538         const struct tcf_proto *first_tp;
1539         int limit = 0;
1540
1541 reclassify:
1542 #endif
1543         for (; tp; tp = rcu_dereference_bh(tp->next)) {
1544                 __be16 protocol = skb_protocol(skb, false);
1545                 int err;
1546
1547                 if (tp->protocol != protocol &&
1548                     tp->protocol != htons(ETH_P_ALL))
1549                         continue;
1550
1551                 err = tp->classify(skb, tp, res);
1552 #ifdef CONFIG_NET_CLS_ACT
1553                 if (unlikely(err == TC_ACT_RECLASSIFY && !compat_mode)) {
1554                         first_tp = orig_tp;
1555                         *last_executed_chain = first_tp->chain->index;
1556                         goto reset;
1557                 } else if (unlikely(TC_ACT_EXT_CMP(err, TC_ACT_GOTO_CHAIN))) {
1558                         first_tp = res->goto_tp;
1559                         *last_executed_chain = err & TC_ACT_EXT_VAL_MASK;
1560                         goto reset;
1561                 }
1562 #endif
1563                 if (err >= 0)
1564                         return err;
1565         }
1566
1567         return TC_ACT_UNSPEC; /* signal: continue lookup */
1568 #ifdef CONFIG_NET_CLS_ACT
1569 reset:
1570         if (unlikely(limit++ >= max_reclassify_loop)) {
1571                 net_notice_ratelimited("%u: reclassify loop, rule prio %u, protocol %02x\n",
1572                                        tp->chain->block->index,
1573                                        tp->prio & 0xffff,
1574                                        ntohs(tp->protocol));
1575                 return TC_ACT_SHOT;
1576         }
1577
1578         tp = first_tp;
1579         goto reclassify;
1580 #endif
1581 }
1582
1583 int tcf_classify(struct sk_buff *skb, const struct tcf_proto *tp,
1584                  struct tcf_result *res, bool compat_mode)
1585 {
1586         u32 last_executed_chain = 0;
1587
1588         return __tcf_classify(skb, tp, tp, res, compat_mode,
1589                               &last_executed_chain);
1590 }
1591 EXPORT_SYMBOL(tcf_classify);
1592
1593 int tcf_classify_ingress(struct sk_buff *skb,
1594                          const struct tcf_block *ingress_block,
1595                          const struct tcf_proto *tp,
1596                          struct tcf_result *res, bool compat_mode)
1597 {
1598 #if !IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
1599         u32 last_executed_chain = 0;
1600
1601         return __tcf_classify(skb, tp, tp, res, compat_mode,
1602                               &last_executed_chain);
1603 #else
1604         u32 last_executed_chain = tp ? tp->chain->index : 0;
1605         const struct tcf_proto *orig_tp = tp;
1606         struct tc_skb_ext *ext;
1607         int ret;
1608
1609         ext = skb_ext_find(skb, TC_SKB_EXT);
1610
1611         if (ext && ext->chain) {
1612                 struct tcf_chain *fchain;
1613
1614                 fchain = tcf_chain_lookup_rcu(ingress_block, ext->chain);
1615                 if (!fchain)
1616                         return TC_ACT_SHOT;
1617
1618                 /* Consume, so cloned/redirect skbs won't inherit ext */
1619                 skb_ext_del(skb, TC_SKB_EXT);
1620
1621                 tp = rcu_dereference_bh(fchain->filter_chain);
1622                 last_executed_chain = fchain->index;
1623         }
1624
1625         ret = __tcf_classify(skb, tp, orig_tp, res, compat_mode,
1626                              &last_executed_chain);
1627
1628         /* If we missed on some chain */
1629         if (ret == TC_ACT_UNSPEC && last_executed_chain) {
1630                 ext = tc_skb_ext_alloc(skb);
1631                 if (WARN_ON_ONCE(!ext))
1632                         return TC_ACT_SHOT;
1633                 ext->chain = last_executed_chain;
1634                 ext->mru = qdisc_skb_cb(skb)->mru;
1635         }
1636
1637         return ret;
1638 #endif
1639 }
1640 EXPORT_SYMBOL(tcf_classify_ingress);
1641
1642 struct tcf_chain_info {
1643         struct tcf_proto __rcu **pprev;
1644         struct tcf_proto __rcu *next;
1645 };
1646
1647 static struct tcf_proto *tcf_chain_tp_prev(struct tcf_chain *chain,
1648                                            struct tcf_chain_info *chain_info)
1649 {
1650         return tcf_chain_dereference(*chain_info->pprev, chain);
1651 }
1652
1653 static int tcf_chain_tp_insert(struct tcf_chain *chain,
1654                                struct tcf_chain_info *chain_info,
1655                                struct tcf_proto *tp)
1656 {
1657         if (chain->flushing)
1658                 return -EAGAIN;
1659
1660         RCU_INIT_POINTER(tp->next, tcf_chain_tp_prev(chain, chain_info));
1661         if (*chain_info->pprev == chain->filter_chain)
1662                 tcf_chain0_head_change(chain, tp);
1663         tcf_proto_get(tp);
1664         rcu_assign_pointer(*chain_info->pprev, tp);
1665
1666         return 0;
1667 }
1668
1669 static void tcf_chain_tp_remove(struct tcf_chain *chain,
1670                                 struct tcf_chain_info *chain_info,
1671                                 struct tcf_proto *tp)
1672 {
1673         struct tcf_proto *next = tcf_chain_dereference(chain_info->next, chain);
1674
1675         tcf_proto_mark_delete(tp);
1676         if (tp == chain->filter_chain)
1677                 tcf_chain0_head_change(chain, next);
1678         RCU_INIT_POINTER(*chain_info->pprev, next);
1679 }
1680
1681 static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain,
1682                                            struct tcf_chain_info *chain_info,
1683                                            u32 protocol, u32 prio,
1684                                            bool prio_allocate);
1685
1686 /* Try to insert new proto.
1687  * If proto with specified priority already exists, free new proto
1688  * and return existing one.
1689  */
1690
1691 static struct tcf_proto *tcf_chain_tp_insert_unique(struct tcf_chain *chain,
1692                                                     struct tcf_proto *tp_new,
1693                                                     u32 protocol, u32 prio,
1694                                                     bool rtnl_held)
1695 {
1696         struct tcf_chain_info chain_info;
1697         struct tcf_proto *tp;
1698         int err = 0;
1699
1700         mutex_lock(&chain->filter_chain_lock);
1701
1702         if (tcf_proto_exists_destroying(chain, tp_new)) {
1703                 mutex_unlock(&chain->filter_chain_lock);
1704                 tcf_proto_destroy(tp_new, rtnl_held, false, NULL);
1705                 return ERR_PTR(-EAGAIN);
1706         }
1707
1708         tp = tcf_chain_tp_find(chain, &chain_info,
1709                                protocol, prio, false);
1710         if (!tp)
1711                 err = tcf_chain_tp_insert(chain, &chain_info, tp_new);
1712         mutex_unlock(&chain->filter_chain_lock);
1713
1714         if (tp) {
1715                 tcf_proto_destroy(tp_new, rtnl_held, false, NULL);
1716                 tp_new = tp;
1717         } else if (err) {
1718                 tcf_proto_destroy(tp_new, rtnl_held, false, NULL);
1719                 tp_new = ERR_PTR(err);
1720         }
1721
1722         return tp_new;
1723 }
1724
1725 static void tcf_chain_tp_delete_empty(struct tcf_chain *chain,
1726                                       struct tcf_proto *tp, bool rtnl_held,
1727                                       struct netlink_ext_ack *extack)
1728 {
1729         struct tcf_chain_info chain_info;
1730         struct tcf_proto *tp_iter;
1731         struct tcf_proto **pprev;
1732         struct tcf_proto *next;
1733
1734         mutex_lock(&chain->filter_chain_lock);
1735
1736         /* Atomically find and remove tp from chain. */
1737         for (pprev = &chain->filter_chain;
1738              (tp_iter = tcf_chain_dereference(*pprev, chain));
1739              pprev = &tp_iter->next) {
1740                 if (tp_iter == tp) {
1741                         chain_info.pprev = pprev;
1742                         chain_info.next = tp_iter->next;
1743                         WARN_ON(tp_iter->deleting);
1744                         break;
1745                 }
1746         }
1747         /* Verify that tp still exists and no new filters were inserted
1748          * concurrently.
1749          * Mark tp for deletion if it is empty.
1750          */
1751         if (!tp_iter || !tcf_proto_check_delete(tp)) {
1752                 mutex_unlock(&chain->filter_chain_lock);
1753                 return;
1754         }
1755
1756         tcf_proto_signal_destroying(chain, tp);
1757         next = tcf_chain_dereference(chain_info.next, chain);
1758         if (tp == chain->filter_chain)
1759                 tcf_chain0_head_change(chain, next);
1760         RCU_INIT_POINTER(*chain_info.pprev, next);
1761         mutex_unlock(&chain->filter_chain_lock);
1762
1763         tcf_proto_put(tp, rtnl_held, extack);
1764 }
1765
1766 static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain,
1767                                            struct tcf_chain_info *chain_info,
1768                                            u32 protocol, u32 prio,
1769                                            bool prio_allocate)
1770 {
1771         struct tcf_proto **pprev;
1772         struct tcf_proto *tp;
1773
1774         /* Check the chain for existence of proto-tcf with this priority */
1775         for (pprev = &chain->filter_chain;
1776              (tp = tcf_chain_dereference(*pprev, chain));
1777              pprev = &tp->next) {
1778                 if (tp->prio >= prio) {
1779                         if (tp->prio == prio) {
1780                                 if (prio_allocate ||
1781                                     (tp->protocol != protocol && protocol))
1782                                         return ERR_PTR(-EINVAL);
1783                         } else {
1784                                 tp = NULL;
1785                         }
1786                         break;
1787                 }
1788         }
1789         chain_info->pprev = pprev;
1790         if (tp) {
1791                 chain_info->next = tp->next;
1792                 tcf_proto_get(tp);
1793         } else {
1794                 chain_info->next = NULL;
1795         }
1796         return tp;
1797 }
1798
1799 static int tcf_fill_node(struct net *net, struct sk_buff *skb,
1800                          struct tcf_proto *tp, struct tcf_block *block,
1801                          struct Qdisc *q, u32 parent, void *fh,
1802                          u32 portid, u32 seq, u16 flags, int event,
1803                          bool terse_dump, bool rtnl_held)
1804 {
1805         struct tcmsg *tcm;
1806         struct nlmsghdr  *nlh;
1807         unsigned char *b = skb_tail_pointer(skb);
1808
1809         nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
1810         if (!nlh)
1811                 goto out_nlmsg_trim;
1812         tcm = nlmsg_data(nlh);
1813         tcm->tcm_family = AF_UNSPEC;
1814         tcm->tcm__pad1 = 0;
1815         tcm->tcm__pad2 = 0;
1816         if (q) {
1817                 tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
1818                 tcm->tcm_parent = parent;
1819         } else {
1820                 tcm->tcm_ifindex = TCM_IFINDEX_MAGIC_BLOCK;
1821                 tcm->tcm_block_index = block->index;
1822         }
1823         tcm->tcm_info = TC_H_MAKE(tp->prio, tp->protocol);
1824         if (nla_put_string(skb, TCA_KIND, tp->ops->kind))
1825                 goto nla_put_failure;
1826         if (nla_put_u32(skb, TCA_CHAIN, tp->chain->index))
1827                 goto nla_put_failure;
1828         if (!fh) {
1829                 tcm->tcm_handle = 0;
1830         } else if (terse_dump) {
1831                 if (tp->ops->terse_dump) {
1832                         if (tp->ops->terse_dump(net, tp, fh, skb, tcm,
1833                                                 rtnl_held) < 0)
1834                                 goto nla_put_failure;
1835                 } else {
1836                         goto cls_op_not_supp;
1837                 }
1838         } else {
1839                 if (tp->ops->dump &&
1840                     tp->ops->dump(net, tp, fh, skb, tcm, rtnl_held) < 0)
1841                         goto nla_put_failure;
1842         }
1843         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1844         return skb->len;
1845
1846 out_nlmsg_trim:
1847 nla_put_failure:
1848 cls_op_not_supp:
1849         nlmsg_trim(skb, b);
1850         return -1;
1851 }
1852
1853 static int tfilter_notify(struct net *net, struct sk_buff *oskb,
1854                           struct nlmsghdr *n, struct tcf_proto *tp,
1855                           struct tcf_block *block, struct Qdisc *q,
1856                           u32 parent, void *fh, int event, bool unicast,
1857                           bool rtnl_held)
1858 {
1859         struct sk_buff *skb;
1860         u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
1861         int err = 0;
1862
1863         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1864         if (!skb)
1865                 return -ENOBUFS;
1866
1867         if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid,
1868                           n->nlmsg_seq, n->nlmsg_flags, event,
1869                           false, rtnl_held) <= 0) {
1870                 kfree_skb(skb);
1871                 return -EINVAL;
1872         }
1873
1874         if (unicast)
1875                 err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
1876         else
1877                 err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1878                                      n->nlmsg_flags & NLM_F_ECHO);
1879
1880         if (err > 0)
1881                 err = 0;
1882         return err;
1883 }
1884
1885 static int tfilter_del_notify(struct net *net, struct sk_buff *oskb,
1886                               struct nlmsghdr *n, struct tcf_proto *tp,
1887                               struct tcf_block *block, struct Qdisc *q,
1888                               u32 parent, void *fh, bool unicast, bool *last,
1889                               bool rtnl_held, struct netlink_ext_ack *extack)
1890 {
1891         struct sk_buff *skb;
1892         u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
1893         int err;
1894
1895         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1896         if (!skb)
1897                 return -ENOBUFS;
1898
1899         if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid,
1900                           n->nlmsg_seq, n->nlmsg_flags, RTM_DELTFILTER,
1901                           false, rtnl_held) <= 0) {
1902                 NL_SET_ERR_MSG(extack, "Failed to build del event notification");
1903                 kfree_skb(skb);
1904                 return -EINVAL;
1905         }
1906
1907         err = tp->ops->delete(tp, fh, last, rtnl_held, extack);
1908         if (err) {
1909                 kfree_skb(skb);
1910                 return err;
1911         }
1912
1913         if (unicast)
1914                 err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
1915         else
1916                 err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1917                                      n->nlmsg_flags & NLM_F_ECHO);
1918         if (err < 0)
1919                 NL_SET_ERR_MSG(extack, "Failed to send filter delete notification");
1920
1921         if (err > 0)
1922                 err = 0;
1923         return err;
1924 }
1925
1926 static void tfilter_notify_chain(struct net *net, struct sk_buff *oskb,
1927                                  struct tcf_block *block, struct Qdisc *q,
1928                                  u32 parent, struct nlmsghdr *n,
1929                                  struct tcf_chain *chain, int event,
1930                                  bool rtnl_held)
1931 {
1932         struct tcf_proto *tp;
1933
1934         for (tp = tcf_get_next_proto(chain, NULL, rtnl_held);
1935              tp; tp = tcf_get_next_proto(chain, tp, rtnl_held))
1936                 tfilter_notify(net, oskb, n, tp, block,
1937                                q, parent, NULL, event, false, rtnl_held);
1938 }
1939
1940 static void tfilter_put(struct tcf_proto *tp, void *fh)
1941 {
1942         if (tp->ops->put && fh)
1943                 tp->ops->put(tp, fh);
1944 }
1945
1946 static int tc_new_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
1947                           struct netlink_ext_ack *extack)
1948 {
1949         struct net *net = sock_net(skb->sk);
1950         struct nlattr *tca[TCA_MAX + 1];
1951         char name[IFNAMSIZ];
1952         struct tcmsg *t;
1953         u32 protocol;
1954         u32 prio;
1955         bool prio_allocate;
1956         u32 parent;
1957         u32 chain_index;
1958         struct Qdisc *q;
1959         struct tcf_chain_info chain_info;
1960         struct tcf_chain *chain;
1961         struct tcf_block *block;
1962         struct tcf_proto *tp;
1963         unsigned long cl;
1964         void *fh;
1965         int err;
1966         int tp_created;
1967         bool rtnl_held = false;
1968
1969         if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
1970                 return -EPERM;
1971
1972 replay:
1973         tp_created = 0;
1974
1975         err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
1976                                      rtm_tca_policy, extack);
1977         if (err < 0)
1978                 return err;
1979
1980         t = nlmsg_data(n);
1981         protocol = TC_H_MIN(t->tcm_info);
1982         prio = TC_H_MAJ(t->tcm_info);
1983         prio_allocate = false;
1984         parent = t->tcm_parent;
1985         tp = NULL;
1986         cl = 0;
1987         block = NULL;
1988         q = NULL;
1989         chain = NULL;
1990
1991         if (prio == 0) {
1992                 /* If no priority is provided by the user,
1993                  * we allocate one.
1994                  */
1995                 if (n->nlmsg_flags & NLM_F_CREATE) {
1996                         prio = TC_H_MAKE(0x80000000U, 0U);
1997                         prio_allocate = true;
1998                 } else {
1999                         NL_SET_ERR_MSG(extack, "Invalid filter command with priority of zero");
2000                         return -ENOENT;
2001                 }
2002         }
2003
2004         /* Find head of filter chain. */
2005
2006         err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack);
2007         if (err)
2008                 return err;
2009
2010         if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
2011                 NL_SET_ERR_MSG(extack, "Specified TC filter name too long");
2012                 err = -EINVAL;
2013                 goto errout;
2014         }
2015
2016         /* Take rtnl mutex if rtnl_held was set to true on previous iteration,
2017          * block is shared (no qdisc found), qdisc is not unlocked, classifier
2018          * type is not specified, classifier is not unlocked.
2019          */
2020         if (rtnl_held ||
2021             (q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
2022             !tcf_proto_is_unlocked(name)) {
2023                 rtnl_held = true;
2024                 rtnl_lock();
2025         }
2026
2027         err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack);
2028         if (err)
2029                 goto errout;
2030
2031         block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index,
2032                                  extack);
2033         if (IS_ERR(block)) {
2034                 err = PTR_ERR(block);
2035                 goto errout;
2036         }
2037         block->classid = parent;
2038
2039         chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2040         if (chain_index > TC_ACT_EXT_VAL_MASK) {
2041                 NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2042                 err = -EINVAL;
2043                 goto errout;
2044         }
2045         chain = tcf_chain_get(block, chain_index, true);
2046         if (!chain) {
2047                 NL_SET_ERR_MSG(extack, "Cannot create specified filter chain");
2048                 err = -ENOMEM;
2049                 goto errout;
2050         }
2051
2052         mutex_lock(&chain->filter_chain_lock);
2053         tp = tcf_chain_tp_find(chain, &chain_info, protocol,
2054                                prio, prio_allocate);
2055         if (IS_ERR(tp)) {
2056                 NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
2057                 err = PTR_ERR(tp);
2058                 goto errout_locked;
2059         }
2060
2061         if (tp == NULL) {
2062                 struct tcf_proto *tp_new = NULL;
2063
2064                 if (chain->flushing) {
2065                         err = -EAGAIN;
2066                         goto errout_locked;
2067                 }
2068
2069                 /* Proto-tcf does not exist, create new one */
2070
2071                 if (tca[TCA_KIND] == NULL || !protocol) {
2072                         NL_SET_ERR_MSG(extack, "Filter kind and protocol must be specified");
2073                         err = -EINVAL;
2074                         goto errout_locked;
2075                 }
2076
2077                 if (!(n->nlmsg_flags & NLM_F_CREATE)) {
2078                         NL_SET_ERR_MSG(extack, "Need both RTM_NEWTFILTER and NLM_F_CREATE to create a new filter");
2079                         err = -ENOENT;
2080                         goto errout_locked;
2081                 }
2082
2083                 if (prio_allocate)
2084                         prio = tcf_auto_prio(tcf_chain_tp_prev(chain,
2085                                                                &chain_info));
2086
2087                 mutex_unlock(&chain->filter_chain_lock);
2088                 tp_new = tcf_proto_create(name, protocol, prio, chain,
2089                                           rtnl_held, extack);
2090                 if (IS_ERR(tp_new)) {
2091                         err = PTR_ERR(tp_new);
2092                         goto errout_tp;
2093                 }
2094
2095                 tp_created = 1;
2096                 tp = tcf_chain_tp_insert_unique(chain, tp_new, protocol, prio,
2097                                                 rtnl_held);
2098                 if (IS_ERR(tp)) {
2099                         err = PTR_ERR(tp);
2100                         goto errout_tp;
2101                 }
2102         } else {
2103                 mutex_unlock(&chain->filter_chain_lock);
2104         }
2105
2106         if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
2107                 NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
2108                 err = -EINVAL;
2109                 goto errout;
2110         }
2111
2112         fh = tp->ops->get(tp, t->tcm_handle);
2113
2114         if (!fh) {
2115                 if (!(n->nlmsg_flags & NLM_F_CREATE)) {
2116                         NL_SET_ERR_MSG(extack, "Need both RTM_NEWTFILTER and NLM_F_CREATE to create a new filter");
2117                         err = -ENOENT;
2118                         goto errout;
2119                 }
2120         } else if (n->nlmsg_flags & NLM_F_EXCL) {
2121                 tfilter_put(tp, fh);
2122                 NL_SET_ERR_MSG(extack, "Filter already exists");
2123                 err = -EEXIST;
2124                 goto errout;
2125         }
2126
2127         if (chain->tmplt_ops && chain->tmplt_ops != tp->ops) {
2128                 tfilter_put(tp, fh);
2129                 NL_SET_ERR_MSG(extack, "Chain template is set to a different filter kind");
2130                 err = -EINVAL;
2131                 goto errout;
2132         }
2133
2134         err = tp->ops->change(net, skb, tp, cl, t->tcm_handle, tca, &fh,
2135                               n->nlmsg_flags & NLM_F_CREATE ? TCA_ACT_NOREPLACE : TCA_ACT_REPLACE,
2136                               rtnl_held, extack);
2137         if (err == 0) {
2138                 tfilter_notify(net, skb, n, tp, block, q, parent, fh,
2139                                RTM_NEWTFILTER, false, rtnl_held);
2140                 tfilter_put(tp, fh);
2141                 /* q pointer is NULL for shared blocks */
2142                 if (q)
2143                         q->flags &= ~TCQ_F_CAN_BYPASS;
2144         }
2145
2146 errout:
2147         if (err && tp_created)
2148                 tcf_chain_tp_delete_empty(chain, tp, rtnl_held, NULL);
2149 errout_tp:
2150         if (chain) {
2151                 if (tp && !IS_ERR(tp))
2152                         tcf_proto_put(tp, rtnl_held, NULL);
2153                 if (!tp_created)
2154                         tcf_chain_put(chain);
2155         }
2156         tcf_block_release(q, block, rtnl_held);
2157
2158         if (rtnl_held)
2159                 rtnl_unlock();
2160
2161         if (err == -EAGAIN) {
2162                 /* Take rtnl lock in case EAGAIN is caused by concurrent flush
2163                  * of target chain.
2164                  */
2165                 rtnl_held = true;
2166                 /* Replay the request. */
2167                 goto replay;
2168         }
2169         return err;
2170
2171 errout_locked:
2172         mutex_unlock(&chain->filter_chain_lock);
2173         goto errout;
2174 }
2175
2176 static int tc_del_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
2177                           struct netlink_ext_ack *extack)
2178 {
2179         struct net *net = sock_net(skb->sk);
2180         struct nlattr *tca[TCA_MAX + 1];
2181         char name[IFNAMSIZ];
2182         struct tcmsg *t;
2183         u32 protocol;
2184         u32 prio;
2185         u32 parent;
2186         u32 chain_index;
2187         struct Qdisc *q = NULL;
2188         struct tcf_chain_info chain_info;
2189         struct tcf_chain *chain = NULL;
2190         struct tcf_block *block = NULL;
2191         struct tcf_proto *tp = NULL;
2192         unsigned long cl = 0;
2193         void *fh = NULL;
2194         int err;
2195         bool rtnl_held = false;
2196
2197         if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
2198                 return -EPERM;
2199
2200         err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
2201                                      rtm_tca_policy, extack);
2202         if (err < 0)
2203                 return err;
2204
2205         t = nlmsg_data(n);
2206         protocol = TC_H_MIN(t->tcm_info);
2207         prio = TC_H_MAJ(t->tcm_info);
2208         parent = t->tcm_parent;
2209
2210         if (prio == 0 && (protocol || t->tcm_handle || tca[TCA_KIND])) {
2211                 NL_SET_ERR_MSG(extack, "Cannot flush filters with protocol, handle or kind set");
2212                 return -ENOENT;
2213         }
2214
2215         /* Find head of filter chain. */
2216
2217         err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack);
2218         if (err)
2219                 return err;
2220
2221         if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
2222                 NL_SET_ERR_MSG(extack, "Specified TC filter name too long");
2223                 err = -EINVAL;
2224                 goto errout;
2225         }
2226         /* Take rtnl mutex if flushing whole chain, block is shared (no qdisc
2227          * found), qdisc is not unlocked, classifier type is not specified,
2228          * classifier is not unlocked.
2229          */
2230         if (!prio ||
2231             (q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
2232             !tcf_proto_is_unlocked(name)) {
2233                 rtnl_held = true;
2234                 rtnl_lock();
2235         }
2236
2237         err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack);
2238         if (err)
2239                 goto errout;
2240
2241         block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index,
2242                                  extack);
2243         if (IS_ERR(block)) {
2244                 err = PTR_ERR(block);
2245                 goto errout;
2246         }
2247
2248         chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2249         if (chain_index > TC_ACT_EXT_VAL_MASK) {
2250                 NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2251                 err = -EINVAL;
2252                 goto errout;
2253         }
2254         chain = tcf_chain_get(block, chain_index, false);
2255         if (!chain) {
2256                 /* User requested flush on non-existent chain. Nothing to do,
2257                  * so just return success.
2258                  */
2259                 if (prio == 0) {
2260                         err = 0;
2261                         goto errout;
2262                 }
2263                 NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
2264                 err = -ENOENT;
2265                 goto errout;
2266         }
2267
2268         if (prio == 0) {
2269                 tfilter_notify_chain(net, skb, block, q, parent, n,
2270                                      chain, RTM_DELTFILTER, rtnl_held);
2271                 tcf_chain_flush(chain, rtnl_held);
2272                 err = 0;
2273                 goto errout;
2274         }
2275
2276         mutex_lock(&chain->filter_chain_lock);
2277         tp = tcf_chain_tp_find(chain, &chain_info, protocol,
2278                                prio, false);
2279         if (!tp || IS_ERR(tp)) {
2280                 NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
2281                 err = tp ? PTR_ERR(tp) : -ENOENT;
2282                 goto errout_locked;
2283         } else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
2284                 NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
2285                 err = -EINVAL;
2286                 goto errout_locked;
2287         } else if (t->tcm_handle == 0) {
2288                 tcf_proto_signal_destroying(chain, tp);
2289                 tcf_chain_tp_remove(chain, &chain_info, tp);
2290                 mutex_unlock(&chain->filter_chain_lock);
2291
2292                 tcf_proto_put(tp, rtnl_held, NULL);
2293                 tfilter_notify(net, skb, n, tp, block, q, parent, fh,
2294                                RTM_DELTFILTER, false, rtnl_held);
2295                 err = 0;
2296                 goto errout;
2297         }
2298         mutex_unlock(&chain->filter_chain_lock);
2299
2300         fh = tp->ops->get(tp, t->tcm_handle);
2301
2302         if (!fh) {
2303                 NL_SET_ERR_MSG(extack, "Specified filter handle not found");
2304                 err = -ENOENT;
2305         } else {
2306                 bool last;
2307
2308                 err = tfilter_del_notify(net, skb, n, tp, block,
2309                                          q, parent, fh, false, &last,
2310                                          rtnl_held, extack);
2311
2312                 if (err)
2313                         goto errout;
2314                 if (last)
2315                         tcf_chain_tp_delete_empty(chain, tp, rtnl_held, extack);
2316         }
2317
2318 errout:
2319         if (chain) {
2320                 if (tp && !IS_ERR(tp))
2321                         tcf_proto_put(tp, rtnl_held, NULL);
2322                 tcf_chain_put(chain);
2323         }
2324         tcf_block_release(q, block, rtnl_held);
2325
2326         if (rtnl_held)
2327                 rtnl_unlock();
2328
2329         return err;
2330
2331 errout_locked:
2332         mutex_unlock(&chain->filter_chain_lock);
2333         goto errout;
2334 }
2335
2336 static int tc_get_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
2337                           struct netlink_ext_ack *extack)
2338 {
2339         struct net *net = sock_net(skb->sk);
2340         struct nlattr *tca[TCA_MAX + 1];
2341         char name[IFNAMSIZ];
2342         struct tcmsg *t;
2343         u32 protocol;
2344         u32 prio;
2345         u32 parent;
2346         u32 chain_index;
2347         struct Qdisc *q = NULL;
2348         struct tcf_chain_info chain_info;
2349         struct tcf_chain *chain = NULL;
2350         struct tcf_block *block = NULL;
2351         struct tcf_proto *tp = NULL;
2352         unsigned long cl = 0;
2353         void *fh = NULL;
2354         int err;
2355         bool rtnl_held = false;
2356
2357         err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
2358                                      rtm_tca_policy, extack);
2359         if (err < 0)
2360                 return err;
2361
2362         t = nlmsg_data(n);
2363         protocol = TC_H_MIN(t->tcm_info);
2364         prio = TC_H_MAJ(t->tcm_info);
2365         parent = t->tcm_parent;
2366
2367         if (prio == 0) {
2368                 NL_SET_ERR_MSG(extack, "Invalid filter command with priority of zero");
2369                 return -ENOENT;
2370         }
2371
2372         /* Find head of filter chain. */
2373
2374         err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack);
2375         if (err)
2376                 return err;
2377
2378         if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
2379                 NL_SET_ERR_MSG(extack, "Specified TC filter name too long");
2380                 err = -EINVAL;
2381                 goto errout;
2382         }
2383         /* Take rtnl mutex if block is shared (no qdisc found), qdisc is not
2384          * unlocked, classifier type is not specified, classifier is not
2385          * unlocked.
2386          */
2387         if ((q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
2388             !tcf_proto_is_unlocked(name)) {
2389                 rtnl_held = true;
2390                 rtnl_lock();
2391         }
2392
2393         err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack);
2394         if (err)
2395                 goto errout;
2396
2397         block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index,
2398                                  extack);
2399         if (IS_ERR(block)) {
2400                 err = PTR_ERR(block);
2401                 goto errout;
2402         }
2403
2404         chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2405         if (chain_index > TC_ACT_EXT_VAL_MASK) {
2406                 NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2407                 err = -EINVAL;
2408                 goto errout;
2409         }
2410         chain = tcf_chain_get(block, chain_index, false);
2411         if (!chain) {
2412                 NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
2413                 err = -EINVAL;
2414                 goto errout;
2415         }
2416
2417         mutex_lock(&chain->filter_chain_lock);
2418         tp = tcf_chain_tp_find(chain, &chain_info, protocol,
2419                                prio, false);
2420         mutex_unlock(&chain->filter_chain_lock);
2421         if (!tp || IS_ERR(tp)) {
2422                 NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
2423                 err = tp ? PTR_ERR(tp) : -ENOENT;
2424                 goto errout;
2425         } else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
2426                 NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
2427                 err = -EINVAL;
2428                 goto errout;
2429         }
2430
2431         fh = tp->ops->get(tp, t->tcm_handle);
2432
2433         if (!fh) {
2434                 NL_SET_ERR_MSG(extack, "Specified filter handle not found");
2435                 err = -ENOENT;
2436         } else {
2437                 err = tfilter_notify(net, skb, n, tp, block, q, parent,
2438                                      fh, RTM_NEWTFILTER, true, rtnl_held);
2439                 if (err < 0)
2440                         NL_SET_ERR_MSG(extack, "Failed to send filter notify message");
2441         }
2442
2443         tfilter_put(tp, fh);
2444 errout:
2445         if (chain) {
2446                 if (tp && !IS_ERR(tp))
2447                         tcf_proto_put(tp, rtnl_held, NULL);
2448                 tcf_chain_put(chain);
2449         }
2450         tcf_block_release(q, block, rtnl_held);
2451
2452         if (rtnl_held)
2453                 rtnl_unlock();
2454
2455         return err;
2456 }
2457
2458 struct tcf_dump_args {
2459         struct tcf_walker w;
2460         struct sk_buff *skb;
2461         struct netlink_callback *cb;
2462         struct tcf_block *block;
2463         struct Qdisc *q;
2464         u32 parent;
2465         bool terse_dump;
2466 };
2467
2468 static int tcf_node_dump(struct tcf_proto *tp, void *n, struct tcf_walker *arg)
2469 {
2470         struct tcf_dump_args *a = (void *)arg;
2471         struct net *net = sock_net(a->skb->sk);
2472
2473         return tcf_fill_node(net, a->skb, tp, a->block, a->q, a->parent,
2474                              n, NETLINK_CB(a->cb->skb).portid,
2475                              a->cb->nlh->nlmsg_seq, NLM_F_MULTI,
2476                              RTM_NEWTFILTER, a->terse_dump, true);
2477 }
2478
2479 static bool tcf_chain_dump(struct tcf_chain *chain, struct Qdisc *q, u32 parent,
2480                            struct sk_buff *skb, struct netlink_callback *cb,
2481                            long index_start, long *p_index, bool terse)
2482 {
2483         struct net *net = sock_net(skb->sk);
2484         struct tcf_block *block = chain->block;
2485         struct tcmsg *tcm = nlmsg_data(cb->nlh);
2486         struct tcf_proto *tp, *tp_prev;
2487         struct tcf_dump_args arg;
2488
2489         for (tp = __tcf_get_next_proto(chain, NULL);
2490              tp;
2491              tp_prev = tp,
2492                      tp = __tcf_get_next_proto(chain, tp),
2493                      tcf_proto_put(tp_prev, true, NULL),
2494                      (*p_index)++) {
2495                 if (*p_index < index_start)
2496                         continue;
2497                 if (TC_H_MAJ(tcm->tcm_info) &&
2498                     TC_H_MAJ(tcm->tcm_info) != tp->prio)
2499                         continue;
2500                 if (TC_H_MIN(tcm->tcm_info) &&
2501                     TC_H_MIN(tcm->tcm_info) != tp->protocol)
2502                         continue;
2503                 if (*p_index > index_start)
2504                         memset(&cb->args[1], 0,
2505                                sizeof(cb->args) - sizeof(cb->args[0]));
2506                 if (cb->args[1] == 0) {
2507                         if (tcf_fill_node(net, skb, tp, block, q, parent, NULL,
2508                                           NETLINK_CB(cb->skb).portid,
2509                                           cb->nlh->nlmsg_seq, NLM_F_MULTI,
2510                                           RTM_NEWTFILTER, false, true) <= 0)
2511                                 goto errout;
2512                         cb->args[1] = 1;
2513                 }
2514                 if (!tp->ops->walk)
2515                         continue;
2516                 arg.w.fn = tcf_node_dump;
2517                 arg.skb = skb;
2518                 arg.cb = cb;
2519                 arg.block = block;
2520                 arg.q = q;
2521                 arg.parent = parent;
2522                 arg.w.stop = 0;
2523                 arg.w.skip = cb->args[1] - 1;
2524                 arg.w.count = 0;
2525                 arg.w.cookie = cb->args[2];
2526                 arg.terse_dump = terse;
2527                 tp->ops->walk(tp, &arg.w, true);
2528                 cb->args[2] = arg.w.cookie;
2529                 cb->args[1] = arg.w.count + 1;
2530                 if (arg.w.stop)
2531                         goto errout;
2532         }
2533         return true;
2534
2535 errout:
2536         tcf_proto_put(tp, true, NULL);
2537         return false;
2538 }
2539
2540 static const struct nla_policy tcf_tfilter_dump_policy[TCA_MAX + 1] = {
2541         [TCA_DUMP_FLAGS] = NLA_POLICY_BITFIELD32(TCA_DUMP_FLAGS_TERSE),
2542 };
2543
2544 /* called with RTNL */
2545 static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb)
2546 {
2547         struct tcf_chain *chain, *chain_prev;
2548         struct net *net = sock_net(skb->sk);
2549         struct nlattr *tca[TCA_MAX + 1];
2550         struct Qdisc *q = NULL;
2551         struct tcf_block *block;
2552         struct tcmsg *tcm = nlmsg_data(cb->nlh);
2553         bool terse_dump = false;
2554         long index_start;
2555         long index;
2556         u32 parent;
2557         int err;
2558
2559         if (nlmsg_len(cb->nlh) < sizeof(*tcm))
2560                 return skb->len;
2561
2562         err = nlmsg_parse_deprecated(cb->nlh, sizeof(*tcm), tca, TCA_MAX,
2563                                      tcf_tfilter_dump_policy, cb->extack);
2564         if (err)
2565                 return err;
2566
2567         if (tca[TCA_DUMP_FLAGS]) {
2568                 struct nla_bitfield32 flags =
2569                         nla_get_bitfield32(tca[TCA_DUMP_FLAGS]);
2570
2571                 terse_dump = flags.value & TCA_DUMP_FLAGS_TERSE;
2572         }
2573
2574         if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
2575                 block = tcf_block_refcnt_get(net, tcm->tcm_block_index);
2576                 if (!block)
2577                         goto out;
2578                 /* If we work with block index, q is NULL and parent value
2579                  * will never be used in the following code. The check
2580                  * in tcf_fill_node prevents it. However, compiler does not
2581                  * see that far, so set parent to zero to silence the warning
2582                  * about parent being uninitialized.
2583                  */
2584                 parent = 0;
2585         } else {
2586                 const struct Qdisc_class_ops *cops;
2587                 struct net_device *dev;
2588                 unsigned long cl = 0;
2589
2590                 dev = __dev_get_by_index(net, tcm->tcm_ifindex);
2591                 if (!dev)
2592                         return skb->len;
2593
2594                 parent = tcm->tcm_parent;
2595                 if (!parent)
2596                         q = rtnl_dereference(dev->qdisc);
2597                 else
2598                         q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
2599                 if (!q)
2600                         goto out;
2601                 cops = q->ops->cl_ops;
2602                 if (!cops)
2603                         goto out;
2604                 if (!cops->tcf_block)
2605                         goto out;
2606                 if (TC_H_MIN(tcm->tcm_parent)) {
2607                         cl = cops->find(q, tcm->tcm_parent);
2608                         if (cl == 0)
2609                                 goto out;
2610                 }
2611                 block = cops->tcf_block(q, cl, NULL);
2612                 if (!block)
2613                         goto out;
2614                 parent = block->classid;
2615                 if (tcf_block_shared(block))
2616                         q = NULL;
2617         }
2618
2619         index_start = cb->args[0];
2620         index = 0;
2621
2622         for (chain = __tcf_get_next_chain(block, NULL);
2623              chain;
2624              chain_prev = chain,
2625                      chain = __tcf_get_next_chain(block, chain),
2626                      tcf_chain_put(chain_prev)) {
2627                 if (tca[TCA_CHAIN] &&
2628                     nla_get_u32(tca[TCA_CHAIN]) != chain->index)
2629                         continue;
2630                 if (!tcf_chain_dump(chain, q, parent, skb, cb,
2631                                     index_start, &index, terse_dump)) {
2632                         tcf_chain_put(chain);
2633                         err = -EMSGSIZE;
2634                         break;
2635                 }
2636         }
2637
2638         if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK)
2639                 tcf_block_refcnt_put(block, true);
2640         cb->args[0] = index;
2641
2642 out:
2643         /* If we did no progress, the error (EMSGSIZE) is real */
2644         if (skb->len == 0 && err)
2645                 return err;
2646         return skb->len;
2647 }
2648
2649 static int tc_chain_fill_node(const struct tcf_proto_ops *tmplt_ops,
2650                               void *tmplt_priv, u32 chain_index,
2651                               struct net *net, struct sk_buff *skb,
2652                               struct tcf_block *block,
2653                               u32 portid, u32 seq, u16 flags, int event)
2654 {
2655         unsigned char *b = skb_tail_pointer(skb);
2656         const struct tcf_proto_ops *ops;
2657         struct nlmsghdr *nlh;
2658         struct tcmsg *tcm;
2659         void *priv;
2660
2661         ops = tmplt_ops;
2662         priv = tmplt_priv;
2663
2664         nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
2665         if (!nlh)
2666                 goto out_nlmsg_trim;
2667         tcm = nlmsg_data(nlh);
2668         tcm->tcm_family = AF_UNSPEC;
2669         tcm->tcm__pad1 = 0;
2670         tcm->tcm__pad2 = 0;
2671         tcm->tcm_handle = 0;
2672         if (block->q) {
2673                 tcm->tcm_ifindex = qdisc_dev(block->q)->ifindex;
2674                 tcm->tcm_parent = block->q->handle;
2675         } else {
2676                 tcm->tcm_ifindex = TCM_IFINDEX_MAGIC_BLOCK;
2677                 tcm->tcm_block_index = block->index;
2678         }
2679
2680         if (nla_put_u32(skb, TCA_CHAIN, chain_index))
2681                 goto nla_put_failure;
2682
2683         if (ops) {
2684                 if (nla_put_string(skb, TCA_KIND, ops->kind))
2685                         goto nla_put_failure;
2686                 if (ops->tmplt_dump(skb, net, priv) < 0)
2687                         goto nla_put_failure;
2688         }
2689
2690         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
2691         return skb->len;
2692
2693 out_nlmsg_trim:
2694 nla_put_failure:
2695         nlmsg_trim(skb, b);
2696         return -EMSGSIZE;
2697 }
2698
2699 static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb,
2700                            u32 seq, u16 flags, int event, bool unicast)
2701 {
2702         u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
2703         struct tcf_block *block = chain->block;
2704         struct net *net = block->net;
2705         struct sk_buff *skb;
2706         int err = 0;
2707
2708         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2709         if (!skb)
2710                 return -ENOBUFS;
2711
2712         if (tc_chain_fill_node(chain->tmplt_ops, chain->tmplt_priv,
2713                                chain->index, net, skb, block, portid,
2714                                seq, flags, event) <= 0) {
2715                 kfree_skb(skb);
2716                 return -EINVAL;
2717         }
2718
2719         if (unicast)
2720                 err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
2721         else
2722                 err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
2723                                      flags & NLM_F_ECHO);
2724
2725         if (err > 0)
2726                 err = 0;
2727         return err;
2728 }
2729
2730 static int tc_chain_notify_delete(const struct tcf_proto_ops *tmplt_ops,
2731                                   void *tmplt_priv, u32 chain_index,
2732                                   struct tcf_block *block, struct sk_buff *oskb,
2733                                   u32 seq, u16 flags, bool unicast)
2734 {
2735         u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
2736         struct net *net = block->net;
2737         struct sk_buff *skb;
2738
2739         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2740         if (!skb)
2741                 return -ENOBUFS;
2742
2743         if (tc_chain_fill_node(tmplt_ops, tmplt_priv, chain_index, net, skb,
2744                                block, portid, seq, flags, RTM_DELCHAIN) <= 0) {
2745                 kfree_skb(skb);
2746                 return -EINVAL;
2747         }
2748
2749         if (unicast)
2750                 return netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
2751
2752         return rtnetlink_send(skb, net, portid, RTNLGRP_TC, flags & NLM_F_ECHO);
2753 }
2754
2755 static int tc_chain_tmplt_add(struct tcf_chain *chain, struct net *net,
2756                               struct nlattr **tca,
2757                               struct netlink_ext_ack *extack)
2758 {
2759         const struct tcf_proto_ops *ops;
2760         char name[IFNAMSIZ];
2761         void *tmplt_priv;
2762
2763         /* If kind is not set, user did not specify template. */
2764         if (!tca[TCA_KIND])
2765                 return 0;
2766
2767         if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
2768                 NL_SET_ERR_MSG(extack, "Specified TC chain template name too long");
2769                 return -EINVAL;
2770         }
2771
2772         ops = tcf_proto_lookup_ops(name, true, extack);
2773         if (IS_ERR(ops))
2774                 return PTR_ERR(ops);
2775         if (!ops->tmplt_create || !ops->tmplt_destroy || !ops->tmplt_dump) {
2776                 NL_SET_ERR_MSG(extack, "Chain templates are not supported with specified classifier");
2777                 module_put(ops->owner);
2778                 return -EOPNOTSUPP;
2779         }
2780
2781         tmplt_priv = ops->tmplt_create(net, chain, tca, extack);
2782         if (IS_ERR(tmplt_priv)) {
2783                 module_put(ops->owner);
2784                 return PTR_ERR(tmplt_priv);
2785         }
2786         chain->tmplt_ops = ops;
2787         chain->tmplt_priv = tmplt_priv;
2788         return 0;
2789 }
2790
2791 static void tc_chain_tmplt_del(const struct tcf_proto_ops *tmplt_ops,
2792                                void *tmplt_priv)
2793 {
2794         /* If template ops are set, no work to do for us. */
2795         if (!tmplt_ops)
2796                 return;
2797
2798         tmplt_ops->tmplt_destroy(tmplt_priv);
2799         module_put(tmplt_ops->owner);
2800 }
2801
2802 /* Add/delete/get a chain */
2803
2804 static int tc_ctl_chain(struct sk_buff *skb, struct nlmsghdr *n,
2805                         struct netlink_ext_ack *extack)
2806 {
2807         struct net *net = sock_net(skb->sk);
2808         struct nlattr *tca[TCA_MAX + 1];
2809         struct tcmsg *t;
2810         u32 parent;
2811         u32 chain_index;
2812         struct Qdisc *q;
2813         struct tcf_chain *chain;
2814         struct tcf_block *block;
2815         unsigned long cl;
2816         int err;
2817
2818         if (n->nlmsg_type != RTM_GETCHAIN &&
2819             !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
2820                 return -EPERM;
2821
2822 replay:
2823         q = NULL;
2824         err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
2825                                      rtm_tca_policy, extack);
2826         if (err < 0)
2827                 return err;
2828
2829         t = nlmsg_data(n);
2830         parent = t->tcm_parent;
2831         cl = 0;
2832
2833         block = tcf_block_find(net, &q, &parent, &cl,
2834                                t->tcm_ifindex, t->tcm_block_index, extack);
2835         if (IS_ERR(block))
2836                 return PTR_ERR(block);
2837
2838         chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2839         if (chain_index > TC_ACT_EXT_VAL_MASK) {
2840                 NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2841                 err = -EINVAL;
2842                 goto errout_block;
2843         }
2844
2845         mutex_lock(&block->lock);
2846         chain = tcf_chain_lookup(block, chain_index);
2847         if (n->nlmsg_type == RTM_NEWCHAIN) {
2848                 if (chain) {
2849                         if (tcf_chain_held_by_acts_only(chain)) {
2850                                 /* The chain exists only because there is
2851                                  * some action referencing it.
2852                                  */
2853                                 tcf_chain_hold(chain);
2854                         } else {
2855                                 NL_SET_ERR_MSG(extack, "Filter chain already exists");
2856                                 err = -EEXIST;
2857                                 goto errout_block_locked;
2858                         }
2859                 } else {
2860                         if (!(n->nlmsg_flags & NLM_F_CREATE)) {
2861                                 NL_SET_ERR_MSG(extack, "Need both RTM_NEWCHAIN and NLM_F_CREATE to create a new chain");
2862                                 err = -ENOENT;
2863                                 goto errout_block_locked;
2864                         }
2865                         chain = tcf_chain_create(block, chain_index);
2866                         if (!chain) {
2867                                 NL_SET_ERR_MSG(extack, "Failed to create filter chain");
2868                                 err = -ENOMEM;
2869                                 goto errout_block_locked;
2870                         }
2871                 }
2872         } else {
2873                 if (!chain || tcf_chain_held_by_acts_only(chain)) {
2874                         NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
2875                         err = -EINVAL;
2876                         goto errout_block_locked;
2877                 }
2878                 tcf_chain_hold(chain);
2879         }
2880
2881         if (n->nlmsg_type == RTM_NEWCHAIN) {
2882                 /* Modifying chain requires holding parent block lock. In case
2883                  * the chain was successfully added, take a reference to the
2884                  * chain. This ensures that an empty chain does not disappear at
2885                  * the end of this function.
2886                  */
2887                 tcf_chain_hold(chain);
2888                 chain->explicitly_created = true;
2889         }
2890         mutex_unlock(&block->lock);
2891
2892         switch (n->nlmsg_type) {
2893         case RTM_NEWCHAIN:
2894                 err = tc_chain_tmplt_add(chain, net, tca, extack);
2895                 if (err) {
2896                         tcf_chain_put_explicitly_created(chain);
2897                         goto errout;
2898                 }
2899
2900                 tc_chain_notify(chain, NULL, 0, NLM_F_CREATE | NLM_F_EXCL,
2901                                 RTM_NEWCHAIN, false);
2902                 break;
2903         case RTM_DELCHAIN:
2904                 tfilter_notify_chain(net, skb, block, q, parent, n,
2905                                      chain, RTM_DELTFILTER, true);
2906                 /* Flush the chain first as the user requested chain removal. */
2907                 tcf_chain_flush(chain, true);
2908                 /* In case the chain was successfully deleted, put a reference
2909                  * to the chain previously taken during addition.
2910                  */
2911                 tcf_chain_put_explicitly_created(chain);
2912                 break;
2913         case RTM_GETCHAIN:
2914                 err = tc_chain_notify(chain, skb, n->nlmsg_seq,
2915                                       n->nlmsg_flags, n->nlmsg_type, true);
2916                 if (err < 0)
2917                         NL_SET_ERR_MSG(extack, "Failed to send chain notify message");
2918                 break;
2919         default:
2920                 err = -EOPNOTSUPP;
2921                 NL_SET_ERR_MSG(extack, "Unsupported message type");
2922                 goto errout;
2923         }
2924
2925 errout:
2926         tcf_chain_put(chain);
2927 errout_block:
2928         tcf_block_release(q, block, true);
2929         if (err == -EAGAIN)
2930                 /* Replay the request. */
2931                 goto replay;
2932         return err;
2933
2934 errout_block_locked:
2935         mutex_unlock(&block->lock);
2936         goto errout_block;
2937 }
2938
2939 /* called with RTNL */
2940 static int tc_dump_chain(struct sk_buff *skb, struct netlink_callback *cb)
2941 {
2942         struct net *net = sock_net(skb->sk);
2943         struct nlattr *tca[TCA_MAX + 1];
2944         struct Qdisc *q = NULL;
2945         struct tcf_block *block;
2946         struct tcmsg *tcm = nlmsg_data(cb->nlh);
2947         struct tcf_chain *chain;
2948         long index_start;
2949         long index;
2950         u32 parent;
2951         int err;
2952
2953         if (nlmsg_len(cb->nlh) < sizeof(*tcm))
2954                 return skb->len;
2955
2956         err = nlmsg_parse_deprecated(cb->nlh, sizeof(*tcm), tca, TCA_MAX,
2957                                      rtm_tca_policy, cb->extack);
2958         if (err)
2959                 return err;
2960
2961         if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
2962                 block = tcf_block_refcnt_get(net, tcm->tcm_block_index);
2963                 if (!block)
2964                         goto out;
2965                 /* If we work with block index, q is NULL and parent value
2966                  * will never be used in the following code. The check
2967                  * in tcf_fill_node prevents it. However, compiler does not
2968                  * see that far, so set parent to zero to silence the warning
2969                  * about parent being uninitialized.
2970                  */
2971                 parent = 0;
2972         } else {
2973                 const struct Qdisc_class_ops *cops;
2974                 struct net_device *dev;
2975                 unsigned long cl = 0;
2976
2977                 dev = __dev_get_by_index(net, tcm->tcm_ifindex);
2978                 if (!dev)
2979                         return skb->len;
2980
2981                 parent = tcm->tcm_parent;
2982                 if (!parent) {
2983                         q = rtnl_dereference(dev->qdisc);
2984                         parent = q->handle;
2985                 } else {
2986                         q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
2987                 }
2988                 if (!q)
2989                         goto out;
2990                 cops = q->ops->cl_ops;
2991                 if (!cops)
2992                         goto out;
2993                 if (!cops->tcf_block)
2994                         goto out;
2995                 if (TC_H_MIN(tcm->tcm_parent)) {
2996                         cl = cops->find(q, tcm->tcm_parent);
2997                         if (cl == 0)
2998                                 goto out;
2999                 }
3000                 block = cops->tcf_block(q, cl, NULL);
3001                 if (!block)
3002                         goto out;
3003                 if (tcf_block_shared(block))
3004                         q = NULL;
3005         }
3006
3007         index_start = cb->args[0];
3008         index = 0;
3009
3010         mutex_lock(&block->lock);
3011         list_for_each_entry(chain, &block->chain_list, list) {
3012                 if ((tca[TCA_CHAIN] &&
3013                      nla_get_u32(tca[TCA_CHAIN]) != chain->index))
3014                         continue;
3015                 if (index < index_start) {
3016                         index++;
3017                         continue;
3018                 }
3019                 if (tcf_chain_held_by_acts_only(chain))
3020                         continue;
3021                 err = tc_chain_fill_node(chain->tmplt_ops, chain->tmplt_priv,
3022                                          chain->index, net, skb, block,
3023                                          NETLINK_CB(cb->skb).portid,
3024                                          cb->nlh->nlmsg_seq, NLM_F_MULTI,
3025                                          RTM_NEWCHAIN);
3026                 if (err <= 0)
3027                         break;
3028                 index++;
3029         }
3030         mutex_unlock(&block->lock);
3031
3032         if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK)
3033                 tcf_block_refcnt_put(block, true);
3034         cb->args[0] = index;
3035
3036 out:
3037         /* If we did no progress, the error (EMSGSIZE) is real */
3038         if (skb->len == 0 && err)
3039                 return err;
3040         return skb->len;
3041 }
3042
3043 void tcf_exts_destroy(struct tcf_exts *exts)
3044 {
3045 #ifdef CONFIG_NET_CLS_ACT
3046         if (exts->actions) {
3047                 tcf_action_destroy(exts->actions, TCA_ACT_UNBIND);
3048                 kfree(exts->actions);
3049         }
3050         exts->nr_actions = 0;
3051 #endif
3052 }
3053 EXPORT_SYMBOL(tcf_exts_destroy);
3054
3055 int tcf_exts_validate(struct net *net, struct tcf_proto *tp, struct nlattr **tb,
3056                       struct nlattr *rate_tlv, struct tcf_exts *exts, bool ovr,
3057                       bool rtnl_held, struct netlink_ext_ack *extack)
3058 {
3059 #ifdef CONFIG_NET_CLS_ACT
3060         {
3061                 int init_res[TCA_ACT_MAX_PRIO] = {};
3062                 struct tc_action *act;
3063                 size_t attr_size = 0;
3064
3065                 if (exts->police && tb[exts->police]) {
3066                         struct tc_action_ops *a_o;
3067
3068                         a_o = tc_action_load_ops("police", tb[exts->police], rtnl_held, extack);
3069                         if (IS_ERR(a_o))
3070                                 return PTR_ERR(a_o);
3071                         act = tcf_action_init_1(net, tp, tb[exts->police],
3072                                                 rate_tlv, "police", ovr,
3073                                                 TCA_ACT_BIND, a_o, init_res,
3074                                                 rtnl_held, extack);
3075                         module_put(a_o->owner);
3076                         if (IS_ERR(act))
3077                                 return PTR_ERR(act);
3078
3079                         act->type = exts->type = TCA_OLD_COMPAT;
3080                         exts->actions[0] = act;
3081                         exts->nr_actions = 1;
3082                         tcf_idr_insert_many(exts->actions);
3083                 } else if (exts->action && tb[exts->action]) {
3084                         int err;
3085
3086                         err = tcf_action_init(net, tp, tb[exts->action],
3087                                               rate_tlv, NULL, ovr, TCA_ACT_BIND,
3088                                               exts->actions, init_res,
3089                                               &attr_size, rtnl_held, extack);
3090                         if (err < 0)
3091                                 return err;
3092                         exts->nr_actions = err;
3093                 }
3094         }
3095 #else
3096         if ((exts->action && tb[exts->action]) ||
3097             (exts->police && tb[exts->police])) {
3098                 NL_SET_ERR_MSG(extack, "Classifier actions are not supported per compile options (CONFIG_NET_CLS_ACT)");
3099                 return -EOPNOTSUPP;
3100         }
3101 #endif
3102
3103         return 0;
3104 }
3105 EXPORT_SYMBOL(tcf_exts_validate);
3106
3107 void tcf_exts_change(struct tcf_exts *dst, struct tcf_exts *src)
3108 {
3109 #ifdef CONFIG_NET_CLS_ACT
3110         struct tcf_exts old = *dst;
3111
3112         *dst = *src;
3113         tcf_exts_destroy(&old);
3114 #endif
3115 }
3116 EXPORT_SYMBOL(tcf_exts_change);
3117
3118 #ifdef CONFIG_NET_CLS_ACT
3119 static struct tc_action *tcf_exts_first_act(struct tcf_exts *exts)
3120 {
3121         if (exts->nr_actions == 0)
3122                 return NULL;
3123         else
3124                 return exts->actions[0];
3125 }
3126 #endif
3127
3128 int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts)
3129 {
3130 #ifdef CONFIG_NET_CLS_ACT
3131         struct nlattr *nest;
3132
3133         if (exts->action && tcf_exts_has_actions(exts)) {
3134                 /*
3135                  * again for backward compatible mode - we want
3136                  * to work with both old and new modes of entering
3137                  * tc data even if iproute2  was newer - jhs
3138                  */
3139                 if (exts->type != TCA_OLD_COMPAT) {
3140                         nest = nla_nest_start_noflag(skb, exts->action);
3141                         if (nest == NULL)
3142                                 goto nla_put_failure;
3143
3144                         if (tcf_action_dump(skb, exts->actions, 0, 0, false)
3145                             < 0)
3146                                 goto nla_put_failure;
3147                         nla_nest_end(skb, nest);
3148                 } else if (exts->police) {
3149                         struct tc_action *act = tcf_exts_first_act(exts);
3150                         nest = nla_nest_start_noflag(skb, exts->police);
3151                         if (nest == NULL || !act)
3152                                 goto nla_put_failure;
3153                         if (tcf_action_dump_old(skb, act, 0, 0) < 0)
3154                                 goto nla_put_failure;
3155                         nla_nest_end(skb, nest);
3156                 }
3157         }
3158         return 0;
3159
3160 nla_put_failure:
3161         nla_nest_cancel(skb, nest);
3162         return -1;
3163 #else
3164         return 0;
3165 #endif
3166 }
3167 EXPORT_SYMBOL(tcf_exts_dump);
3168
3169 int tcf_exts_terse_dump(struct sk_buff *skb, struct tcf_exts *exts)
3170 {
3171 #ifdef CONFIG_NET_CLS_ACT
3172         struct nlattr *nest;
3173
3174         if (!exts->action || !tcf_exts_has_actions(exts))
3175                 return 0;
3176
3177         nest = nla_nest_start_noflag(skb, exts->action);
3178         if (!nest)
3179                 goto nla_put_failure;
3180
3181         if (tcf_action_dump(skb, exts->actions, 0, 0, true) < 0)
3182                 goto nla_put_failure;
3183         nla_nest_end(skb, nest);
3184         return 0;
3185
3186 nla_put_failure:
3187         nla_nest_cancel(skb, nest);
3188         return -1;
3189 #else
3190         return 0;
3191 #endif
3192 }
3193 EXPORT_SYMBOL(tcf_exts_terse_dump);
3194
3195 int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts)
3196 {
3197 #ifdef CONFIG_NET_CLS_ACT
3198         struct tc_action *a = tcf_exts_first_act(exts);
3199         if (a != NULL && tcf_action_copy_stats(skb, a, 1) < 0)
3200                 return -1;
3201 #endif
3202         return 0;
3203 }
3204 EXPORT_SYMBOL(tcf_exts_dump_stats);
3205
3206 static void tcf_block_offload_inc(struct tcf_block *block, u32 *flags)
3207 {
3208         if (*flags & TCA_CLS_FLAGS_IN_HW)
3209                 return;
3210         *flags |= TCA_CLS_FLAGS_IN_HW;
3211         atomic_inc(&block->offloadcnt);
3212 }
3213
3214 static void tcf_block_offload_dec(struct tcf_block *block, u32 *flags)
3215 {
3216         if (!(*flags & TCA_CLS_FLAGS_IN_HW))
3217                 return;
3218         *flags &= ~TCA_CLS_FLAGS_IN_HW;
3219         atomic_dec(&block->offloadcnt);
3220 }
3221
3222 static void tc_cls_offload_cnt_update(struct tcf_block *block,
3223                                       struct tcf_proto *tp, u32 *cnt,
3224                                       u32 *flags, u32 diff, bool add)
3225 {
3226         lockdep_assert_held(&block->cb_lock);
3227
3228         spin_lock(&tp->lock);
3229         if (add) {
3230                 if (!*cnt)
3231                         tcf_block_offload_inc(block, flags);
3232                 *cnt += diff;
3233         } else {
3234                 *cnt -= diff;
3235                 if (!*cnt)
3236                         tcf_block_offload_dec(block, flags);
3237         }
3238         spin_unlock(&tp->lock);
3239 }
3240
3241 static void
3242 tc_cls_offload_cnt_reset(struct tcf_block *block, struct tcf_proto *tp,
3243                          u32 *cnt, u32 *flags)
3244 {
3245         lockdep_assert_held(&block->cb_lock);
3246
3247         spin_lock(&tp->lock);
3248         tcf_block_offload_dec(block, flags);
3249         *cnt = 0;
3250         spin_unlock(&tp->lock);
3251 }
3252
3253 static int
3254 __tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type,
3255                    void *type_data, bool err_stop)
3256 {
3257         struct flow_block_cb *block_cb;
3258         int ok_count = 0;
3259         int err;
3260
3261         list_for_each_entry(block_cb, &block->flow_block.cb_list, list) {
3262                 err = block_cb->cb(type, type_data, block_cb->cb_priv);
3263                 if (err) {
3264                         if (err_stop)
3265                                 return err;
3266                 } else {
3267                         ok_count++;
3268                 }
3269         }
3270         return ok_count;
3271 }
3272
3273 int tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type,
3274                      void *type_data, bool err_stop, bool rtnl_held)
3275 {
3276         bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3277         int ok_count;
3278
3279 retry:
3280         if (take_rtnl)
3281                 rtnl_lock();
3282         down_read(&block->cb_lock);
3283         /* Need to obtain rtnl lock if block is bound to devs that require it.
3284          * In block bind code cb_lock is obtained while holding rtnl, so we must
3285          * obtain the locks in same order here.
3286          */
3287         if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3288                 up_read(&block->cb_lock);
3289                 take_rtnl = true;
3290                 goto retry;
3291         }
3292
3293         ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3294
3295         up_read(&block->cb_lock);
3296         if (take_rtnl)
3297                 rtnl_unlock();
3298         return ok_count;
3299 }
3300 EXPORT_SYMBOL(tc_setup_cb_call);
3301
3302 /* Non-destructive filter add. If filter that wasn't already in hardware is
3303  * successfully offloaded, increment block offloads counter. On failure,
3304  * previously offloaded filter is considered to be intact and offloads counter
3305  * is not decremented.
3306  */
3307
3308 int tc_setup_cb_add(struct tcf_block *block, struct tcf_proto *tp,
3309                     enum tc_setup_type type, void *type_data, bool err_stop,
3310                     u32 *flags, unsigned int *in_hw_count, bool rtnl_held)
3311 {
3312         bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3313         int ok_count;
3314
3315 retry:
3316         if (take_rtnl)
3317                 rtnl_lock();
3318         down_read(&block->cb_lock);
3319         /* Need to obtain rtnl lock if block is bound to devs that require it.
3320          * In block bind code cb_lock is obtained while holding rtnl, so we must
3321          * obtain the locks in same order here.
3322          */
3323         if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3324                 up_read(&block->cb_lock);
3325                 take_rtnl = true;
3326                 goto retry;
3327         }
3328
3329         /* Make sure all netdevs sharing this block are offload-capable. */
3330         if (block->nooffloaddevcnt && err_stop) {
3331                 ok_count = -EOPNOTSUPP;
3332                 goto err_unlock;
3333         }
3334
3335         ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3336         if (ok_count < 0)
3337                 goto err_unlock;
3338
3339         if (tp->ops->hw_add)
3340                 tp->ops->hw_add(tp, type_data);
3341         if (ok_count > 0)
3342                 tc_cls_offload_cnt_update(block, tp, in_hw_count, flags,
3343                                           ok_count, true);
3344 err_unlock:
3345         up_read(&block->cb_lock);
3346         if (take_rtnl)
3347                 rtnl_unlock();
3348         return ok_count < 0 ? ok_count : 0;
3349 }
3350 EXPORT_SYMBOL(tc_setup_cb_add);
3351
3352 /* Destructive filter replace. If filter that wasn't already in hardware is
3353  * successfully offloaded, increment block offload counter. On failure,
3354  * previously offloaded filter is considered to be destroyed and offload counter
3355  * is decremented.
3356  */
3357
3358 int tc_setup_cb_replace(struct tcf_block *block, struct tcf_proto *tp,
3359                         enum tc_setup_type type, void *type_data, bool err_stop,
3360                         u32 *old_flags, unsigned int *old_in_hw_count,
3361                         u32 *new_flags, unsigned int *new_in_hw_count,
3362                         bool rtnl_held)
3363 {
3364         bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3365         int ok_count;
3366
3367 retry:
3368         if (take_rtnl)
3369                 rtnl_lock();
3370         down_read(&block->cb_lock);
3371         /* Need to obtain rtnl lock if block is bound to devs that require it.
3372          * In block bind code cb_lock is obtained while holding rtnl, so we must
3373          * obtain the locks in same order here.
3374          */
3375         if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3376                 up_read(&block->cb_lock);
3377                 take_rtnl = true;
3378                 goto retry;
3379         }
3380
3381         /* Make sure all netdevs sharing this block are offload-capable. */
3382         if (block->nooffloaddevcnt && err_stop) {
3383                 ok_count = -EOPNOTSUPP;
3384                 goto err_unlock;
3385         }
3386
3387         tc_cls_offload_cnt_reset(block, tp, old_in_hw_count, old_flags);
3388         if (tp->ops->hw_del)
3389                 tp->ops->hw_del(tp, type_data);
3390
3391         ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3392         if (ok_count < 0)
3393                 goto err_unlock;
3394
3395         if (tp->ops->hw_add)
3396                 tp->ops->hw_add(tp, type_data);
3397         if (ok_count > 0)
3398                 tc_cls_offload_cnt_update(block, tp, new_in_hw_count,
3399                                           new_flags, ok_count, true);
3400 err_unlock:
3401         up_read(&block->cb_lock);
3402         if (take_rtnl)
3403                 rtnl_unlock();
3404         return ok_count < 0 ? ok_count : 0;
3405 }
3406 EXPORT_SYMBOL(tc_setup_cb_replace);
3407
3408 /* Destroy filter and decrement block offload counter, if filter was previously
3409  * offloaded.
3410  */
3411
3412 int tc_setup_cb_destroy(struct tcf_block *block, struct tcf_proto *tp,
3413                         enum tc_setup_type type, void *type_data, bool err_stop,
3414                         u32 *flags, unsigned int *in_hw_count, bool rtnl_held)
3415 {
3416         bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3417         int ok_count;
3418
3419 retry:
3420         if (take_rtnl)
3421                 rtnl_lock();
3422         down_read(&block->cb_lock);
3423         /* Need to obtain rtnl lock if block is bound to devs that require it.
3424          * In block bind code cb_lock is obtained while holding rtnl, so we must
3425          * obtain the locks in same order here.
3426          */
3427         if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3428                 up_read(&block->cb_lock);
3429                 take_rtnl = true;
3430                 goto retry;
3431         }
3432
3433         ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3434
3435         tc_cls_offload_cnt_reset(block, tp, in_hw_count, flags);
3436         if (tp->ops->hw_del)
3437                 tp->ops->hw_del(tp, type_data);
3438
3439         up_read(&block->cb_lock);
3440         if (take_rtnl)
3441                 rtnl_unlock();
3442         return ok_count < 0 ? ok_count : 0;
3443 }
3444 EXPORT_SYMBOL(tc_setup_cb_destroy);
3445
3446 int tc_setup_cb_reoffload(struct tcf_block *block, struct tcf_proto *tp,
3447                           bool add, flow_setup_cb_t *cb,
3448                           enum tc_setup_type type, void *type_data,
3449                           void *cb_priv, u32 *flags, unsigned int *in_hw_count)
3450 {
3451         int err = cb(type, type_data, cb_priv);
3452
3453         if (err) {
3454                 if (add && tc_skip_sw(*flags))
3455                         return err;
3456         } else {
3457                 tc_cls_offload_cnt_update(block, tp, in_hw_count, flags, 1,
3458                                           add);
3459         }
3460
3461         return 0;
3462 }
3463 EXPORT_SYMBOL(tc_setup_cb_reoffload);
3464
3465 static int tcf_act_get_cookie(struct flow_action_entry *entry,
3466                               const struct tc_action *act)
3467 {
3468         struct tc_cookie *cookie;
3469         int err = 0;
3470
3471         rcu_read_lock();
3472         cookie = rcu_dereference(act->act_cookie);
3473         if (cookie) {
3474                 entry->cookie = flow_action_cookie_create(cookie->data,
3475                                                           cookie->len,
3476                                                           GFP_ATOMIC);
3477                 if (!entry->cookie)
3478                         err = -ENOMEM;
3479         }
3480         rcu_read_unlock();
3481         return err;
3482 }
3483
3484 static void tcf_act_put_cookie(struct flow_action_entry *entry)
3485 {
3486         flow_action_cookie_destroy(entry->cookie);
3487 }
3488
3489 void tc_cleanup_flow_action(struct flow_action *flow_action)
3490 {
3491         struct flow_action_entry *entry;
3492         int i;
3493
3494         flow_action_for_each(i, entry, flow_action) {
3495                 tcf_act_put_cookie(entry);
3496                 if (entry->destructor)
3497                         entry->destructor(entry->destructor_priv);
3498         }
3499 }
3500 EXPORT_SYMBOL(tc_cleanup_flow_action);
3501
3502 static void tcf_mirred_get_dev(struct flow_action_entry *entry,
3503                                const struct tc_action *act)
3504 {
3505 #ifdef CONFIG_NET_CLS_ACT
3506         entry->dev = act->ops->get_dev(act, &entry->destructor);
3507         if (!entry->dev)
3508                 return;
3509         entry->destructor_priv = entry->dev;
3510 #endif
3511 }
3512
3513 static void tcf_tunnel_encap_put_tunnel(void *priv)
3514 {
3515         struct ip_tunnel_info *tunnel = priv;
3516
3517         kfree(tunnel);
3518 }
3519
3520 static int tcf_tunnel_encap_get_tunnel(struct flow_action_entry *entry,
3521                                        const struct tc_action *act)
3522 {
3523         entry->tunnel = tcf_tunnel_info_copy(act);
3524         if (!entry->tunnel)
3525                 return -ENOMEM;
3526         entry->destructor = tcf_tunnel_encap_put_tunnel;
3527         entry->destructor_priv = entry->tunnel;
3528         return 0;
3529 }
3530
3531 static void tcf_sample_get_group(struct flow_action_entry *entry,
3532                                  const struct tc_action *act)
3533 {
3534 #ifdef CONFIG_NET_CLS_ACT
3535         entry->sample.psample_group =
3536                 act->ops->get_psample_group(act, &entry->destructor);
3537         entry->destructor_priv = entry->sample.psample_group;
3538 #endif
3539 }
3540
3541 static void tcf_gate_entry_destructor(void *priv)
3542 {
3543         struct action_gate_entry *oe = priv;
3544
3545         kfree(oe);
3546 }
3547
3548 static int tcf_gate_get_entries(struct flow_action_entry *entry,
3549                                 const struct tc_action *act)
3550 {
3551         entry->gate.entries = tcf_gate_get_list(act);
3552
3553         if (!entry->gate.entries)
3554                 return -EINVAL;
3555
3556         entry->destructor = tcf_gate_entry_destructor;
3557         entry->destructor_priv = entry->gate.entries;
3558
3559         return 0;
3560 }
3561
3562 static enum flow_action_hw_stats tc_act_hw_stats(u8 hw_stats)
3563 {
3564         if (WARN_ON_ONCE(hw_stats > TCA_ACT_HW_STATS_ANY))
3565                 return FLOW_ACTION_HW_STATS_DONT_CARE;
3566         else if (!hw_stats)
3567                 return FLOW_ACTION_HW_STATS_DISABLED;
3568
3569         return hw_stats;
3570 }
3571
3572 int tc_setup_flow_action(struct flow_action *flow_action,
3573                          const struct tcf_exts *exts)
3574 {
3575         struct tc_action *act;
3576         int i, j, k, err = 0;
3577
3578         BUILD_BUG_ON(TCA_ACT_HW_STATS_ANY != FLOW_ACTION_HW_STATS_ANY);
3579         BUILD_BUG_ON(TCA_ACT_HW_STATS_IMMEDIATE != FLOW_ACTION_HW_STATS_IMMEDIATE);
3580         BUILD_BUG_ON(TCA_ACT_HW_STATS_DELAYED != FLOW_ACTION_HW_STATS_DELAYED);
3581
3582         if (!exts)
3583                 return 0;
3584
3585         j = 0;
3586         tcf_exts_for_each_action(i, act, exts) {
3587                 struct flow_action_entry *entry;
3588
3589                 entry = &flow_action->entries[j];
3590                 spin_lock_bh(&act->tcfa_lock);
3591                 err = tcf_act_get_cookie(entry, act);
3592                 if (err)
3593                         goto err_out_locked;
3594
3595                 entry->hw_stats = tc_act_hw_stats(act->hw_stats);
3596
3597                 if (is_tcf_gact_ok(act)) {
3598                         entry->id = FLOW_ACTION_ACCEPT;
3599                 } else if (is_tcf_gact_shot(act)) {
3600                         entry->id = FLOW_ACTION_DROP;
3601                 } else if (is_tcf_gact_trap(act)) {
3602                         entry->id = FLOW_ACTION_TRAP;
3603                 } else if (is_tcf_gact_goto_chain(act)) {
3604                         entry->id = FLOW_ACTION_GOTO;
3605                         entry->chain_index = tcf_gact_goto_chain_index(act);
3606                 } else if (is_tcf_mirred_egress_redirect(act)) {
3607                         entry->id = FLOW_ACTION_REDIRECT;
3608                         tcf_mirred_get_dev(entry, act);
3609                 } else if (is_tcf_mirred_egress_mirror(act)) {
3610                         entry->id = FLOW_ACTION_MIRRED;
3611                         tcf_mirred_get_dev(entry, act);
3612                 } else if (is_tcf_mirred_ingress_redirect(act)) {
3613                         entry->id = FLOW_ACTION_REDIRECT_INGRESS;
3614                         tcf_mirred_get_dev(entry, act);
3615                 } else if (is_tcf_mirred_ingress_mirror(act)) {
3616                         entry->id = FLOW_ACTION_MIRRED_INGRESS;
3617                         tcf_mirred_get_dev(entry, act);
3618                 } else if (is_tcf_vlan(act)) {
3619                         switch (tcf_vlan_action(act)) {
3620                         case TCA_VLAN_ACT_PUSH:
3621                                 entry->id = FLOW_ACTION_VLAN_PUSH;
3622                                 entry->vlan.vid = tcf_vlan_push_vid(act);
3623                                 entry->vlan.proto = tcf_vlan_push_proto(act);
3624                                 entry->vlan.prio = tcf_vlan_push_prio(act);
3625                                 break;
3626                         case TCA_VLAN_ACT_POP:
3627                                 entry->id = FLOW_ACTION_VLAN_POP;
3628                                 break;
3629                         case TCA_VLAN_ACT_MODIFY:
3630                                 entry->id = FLOW_ACTION_VLAN_MANGLE;
3631                                 entry->vlan.vid = tcf_vlan_push_vid(act);
3632                                 entry->vlan.proto = tcf_vlan_push_proto(act);
3633                                 entry->vlan.prio = tcf_vlan_push_prio(act);
3634                                 break;
3635                         default:
3636                                 err = -EOPNOTSUPP;
3637                                 goto err_out_locked;
3638                         }
3639                 } else if (is_tcf_tunnel_set(act)) {
3640                         entry->id = FLOW_ACTION_TUNNEL_ENCAP;
3641                         err = tcf_tunnel_encap_get_tunnel(entry, act);
3642                         if (err)
3643                                 goto err_out_locked;
3644                 } else if (is_tcf_tunnel_release(act)) {
3645                         entry->id = FLOW_ACTION_TUNNEL_DECAP;
3646                 } else if (is_tcf_pedit(act)) {
3647                         for (k = 0; k < tcf_pedit_nkeys(act); k++) {
3648                                 switch (tcf_pedit_cmd(act, k)) {
3649                                 case TCA_PEDIT_KEY_EX_CMD_SET:
3650                                         entry->id = FLOW_ACTION_MANGLE;
3651                                         break;
3652                                 case TCA_PEDIT_KEY_EX_CMD_ADD:
3653                                         entry->id = FLOW_ACTION_ADD;
3654                                         break;
3655                                 default:
3656                                         err = -EOPNOTSUPP;
3657                                         goto err_out_locked;
3658                                 }
3659                                 entry->mangle.htype = tcf_pedit_htype(act, k);
3660                                 entry->mangle.mask = tcf_pedit_mask(act, k);
3661                                 entry->mangle.val = tcf_pedit_val(act, k);
3662                                 entry->mangle.offset = tcf_pedit_offset(act, k);
3663                                 entry->hw_stats = tc_act_hw_stats(act->hw_stats);
3664                                 entry = &flow_action->entries[++j];
3665                         }
3666                 } else if (is_tcf_csum(act)) {
3667                         entry->id = FLOW_ACTION_CSUM;
3668                         entry->csum_flags = tcf_csum_update_flags(act);
3669                 } else if (is_tcf_skbedit_mark(act)) {
3670                         entry->id = FLOW_ACTION_MARK;
3671                         entry->mark = tcf_skbedit_mark(act);
3672                 } else if (is_tcf_sample(act)) {
3673                         entry->id = FLOW_ACTION_SAMPLE;
3674                         entry->sample.trunc_size = tcf_sample_trunc_size(act);
3675                         entry->sample.truncate = tcf_sample_truncate(act);
3676                         entry->sample.rate = tcf_sample_rate(act);
3677                         tcf_sample_get_group(entry, act);
3678                 } else if (is_tcf_police(act)) {
3679                         entry->id = FLOW_ACTION_POLICE;
3680                         entry->police.burst = tcf_police_burst(act);
3681                         entry->police.rate_bytes_ps =
3682                                 tcf_police_rate_bytes_ps(act);
3683                         entry->police.mtu = tcf_police_tcfp_mtu(act);
3684                         entry->police.index = act->tcfa_index;
3685                 } else if (is_tcf_ct(act)) {
3686                         entry->id = FLOW_ACTION_CT;
3687                         entry->ct.action = tcf_ct_action(act);
3688                         entry->ct.zone = tcf_ct_zone(act);
3689                         entry->ct.flow_table = tcf_ct_ft(act);
3690                 } else if (is_tcf_mpls(act)) {
3691                         switch (tcf_mpls_action(act)) {
3692                         case TCA_MPLS_ACT_PUSH:
3693                                 entry->id = FLOW_ACTION_MPLS_PUSH;
3694                                 entry->mpls_push.proto = tcf_mpls_proto(act);
3695                                 entry->mpls_push.label = tcf_mpls_label(act);
3696                                 entry->mpls_push.tc = tcf_mpls_tc(act);
3697                                 entry->mpls_push.bos = tcf_mpls_bos(act);
3698                                 entry->mpls_push.ttl = tcf_mpls_ttl(act);
3699                                 break;
3700                         case TCA_MPLS_ACT_POP:
3701                                 entry->id = FLOW_ACTION_MPLS_POP;
3702                                 entry->mpls_pop.proto = tcf_mpls_proto(act);
3703                                 break;
3704                         case TCA_MPLS_ACT_MODIFY:
3705                                 entry->id = FLOW_ACTION_MPLS_MANGLE;
3706                                 entry->mpls_mangle.label = tcf_mpls_label(act);
3707                                 entry->mpls_mangle.tc = tcf_mpls_tc(act);
3708                                 entry->mpls_mangle.bos = tcf_mpls_bos(act);
3709                                 entry->mpls_mangle.ttl = tcf_mpls_ttl(act);
3710                                 break;
3711                         default:
3712                                 err = -EOPNOTSUPP;
3713                                 goto err_out_locked;
3714                         }
3715                 } else if (is_tcf_skbedit_ptype(act)) {
3716                         entry->id = FLOW_ACTION_PTYPE;
3717                         entry->ptype = tcf_skbedit_ptype(act);
3718                 } else if (is_tcf_skbedit_priority(act)) {
3719                         entry->id = FLOW_ACTION_PRIORITY;
3720                         entry->priority = tcf_skbedit_priority(act);
3721                 } else if (is_tcf_gate(act)) {
3722                         entry->id = FLOW_ACTION_GATE;
3723                         entry->gate.index = tcf_gate_index(act);
3724                         entry->gate.prio = tcf_gate_prio(act);
3725                         entry->gate.basetime = tcf_gate_basetime(act);
3726                         entry->gate.cycletime = tcf_gate_cycletime(act);
3727                         entry->gate.cycletimeext = tcf_gate_cycletimeext(act);
3728                         entry->gate.num_entries = tcf_gate_num_entries(act);
3729                         err = tcf_gate_get_entries(entry, act);
3730                         if (err)
3731                                 goto err_out_locked;
3732                 } else {
3733                         err = -EOPNOTSUPP;
3734                         goto err_out_locked;
3735                 }
3736                 spin_unlock_bh(&act->tcfa_lock);
3737
3738                 if (!is_tcf_pedit(act))
3739                         j++;
3740         }
3741
3742 err_out:
3743         if (err)
3744                 tc_cleanup_flow_action(flow_action);
3745
3746         return err;
3747 err_out_locked:
3748         spin_unlock_bh(&act->tcfa_lock);
3749         goto err_out;
3750 }
3751 EXPORT_SYMBOL(tc_setup_flow_action);
3752
3753 unsigned int tcf_exts_num_actions(struct tcf_exts *exts)
3754 {
3755         unsigned int num_acts = 0;
3756         struct tc_action *act;
3757         int i;
3758
3759         tcf_exts_for_each_action(i, act, exts) {
3760                 if (is_tcf_pedit(act))
3761                         num_acts += tcf_pedit_nkeys(act);
3762                 else
3763                         num_acts++;
3764         }
3765         return num_acts;
3766 }
3767 EXPORT_SYMBOL(tcf_exts_num_actions);
3768
3769 #ifdef CONFIG_NET_CLS_ACT
3770 static int tcf_qevent_parse_block_index(struct nlattr *block_index_attr,
3771                                         u32 *p_block_index,
3772                                         struct netlink_ext_ack *extack)
3773 {
3774         *p_block_index = nla_get_u32(block_index_attr);
3775         if (!*p_block_index) {
3776                 NL_SET_ERR_MSG(extack, "Block number may not be zero");
3777                 return -EINVAL;
3778         }
3779
3780         return 0;
3781 }
3782
3783 int tcf_qevent_init(struct tcf_qevent *qe, struct Qdisc *sch,
3784                     enum flow_block_binder_type binder_type,
3785                     struct nlattr *block_index_attr,
3786                     struct netlink_ext_ack *extack)
3787 {
3788         u32 block_index;
3789         int err;
3790
3791         if (!block_index_attr)
3792                 return 0;
3793
3794         err = tcf_qevent_parse_block_index(block_index_attr, &block_index, extack);
3795         if (err)
3796                 return err;
3797
3798         if (!block_index)
3799                 return 0;
3800
3801         qe->info.binder_type = binder_type;
3802         qe->info.chain_head_change = tcf_chain_head_change_dflt;
3803         qe->info.chain_head_change_priv = &qe->filter_chain;
3804         qe->info.block_index = block_index;
3805
3806         return tcf_block_get_ext(&qe->block, sch, &qe->info, extack);
3807 }
3808 EXPORT_SYMBOL(tcf_qevent_init);
3809
3810 void tcf_qevent_destroy(struct tcf_qevent *qe, struct Qdisc *sch)
3811 {
3812         if (qe->info.block_index)
3813                 tcf_block_put_ext(qe->block, sch, &qe->info);
3814 }
3815 EXPORT_SYMBOL(tcf_qevent_destroy);
3816
3817 int tcf_qevent_validate_change(struct tcf_qevent *qe, struct nlattr *block_index_attr,
3818                                struct netlink_ext_ack *extack)
3819 {
3820         u32 block_index;
3821         int err;
3822
3823         if (!block_index_attr)
3824                 return 0;
3825
3826         err = tcf_qevent_parse_block_index(block_index_attr, &block_index, extack);
3827         if (err)
3828                 return err;
3829
3830         /* Bounce newly-configured block or change in block. */
3831         if (block_index != qe->info.block_index) {
3832                 NL_SET_ERR_MSG(extack, "Change of blocks is not supported");
3833                 return -EINVAL;
3834         }
3835
3836         return 0;
3837 }
3838 EXPORT_SYMBOL(tcf_qevent_validate_change);
3839
3840 struct sk_buff *tcf_qevent_handle(struct tcf_qevent *qe, struct Qdisc *sch, struct sk_buff *skb,
3841                                   struct sk_buff **to_free, int *ret)
3842 {
3843         struct tcf_result cl_res;
3844         struct tcf_proto *fl;
3845
3846         if (!qe->info.block_index)
3847                 return skb;
3848
3849         fl = rcu_dereference_bh(qe->filter_chain);
3850
3851         switch (tcf_classify(skb, fl, &cl_res, false)) {
3852         case TC_ACT_SHOT:
3853                 qdisc_qstats_drop(sch);
3854                 __qdisc_drop(skb, to_free);
3855                 *ret = __NET_XMIT_BYPASS;
3856                 return NULL;
3857         case TC_ACT_STOLEN:
3858         case TC_ACT_QUEUED:
3859         case TC_ACT_TRAP:
3860                 __qdisc_drop(skb, to_free);
3861                 *ret = __NET_XMIT_STOLEN;
3862                 return NULL;
3863         case TC_ACT_REDIRECT:
3864                 skb_do_redirect(skb);
3865                 *ret = __NET_XMIT_STOLEN;
3866                 return NULL;
3867         }
3868
3869         return skb;
3870 }
3871 EXPORT_SYMBOL(tcf_qevent_handle);
3872
3873 int tcf_qevent_dump(struct sk_buff *skb, int attr_name, struct tcf_qevent *qe)
3874 {
3875         if (!qe->info.block_index)
3876                 return 0;
3877         return nla_put_u32(skb, attr_name, qe->info.block_index);
3878 }
3879 EXPORT_SYMBOL(tcf_qevent_dump);
3880 #endif
3881
3882 static __net_init int tcf_net_init(struct net *net)
3883 {
3884         struct tcf_net *tn = net_generic(net, tcf_net_id);
3885
3886         spin_lock_init(&tn->idr_lock);
3887         idr_init(&tn->idr);
3888         return 0;
3889 }
3890
3891 static void __net_exit tcf_net_exit(struct net *net)
3892 {
3893         struct tcf_net *tn = net_generic(net, tcf_net_id);
3894
3895         idr_destroy(&tn->idr);
3896 }
3897
3898 static struct pernet_operations tcf_net_ops = {
3899         .init = tcf_net_init,
3900         .exit = tcf_net_exit,
3901         .id   = &tcf_net_id,
3902         .size = sizeof(struct tcf_net),
3903 };
3904
3905 static int __init tc_filter_init(void)
3906 {
3907         int err;
3908
3909         tc_filter_wq = alloc_ordered_workqueue("tc_filter_workqueue", 0);
3910         if (!tc_filter_wq)
3911                 return -ENOMEM;
3912
3913         err = register_pernet_subsys(&tcf_net_ops);
3914         if (err)
3915                 goto err_register_pernet_subsys;
3916
3917         rtnl_register(PF_UNSPEC, RTM_NEWTFILTER, tc_new_tfilter, NULL,
3918                       RTNL_FLAG_DOIT_UNLOCKED);
3919         rtnl_register(PF_UNSPEC, RTM_DELTFILTER, tc_del_tfilter, NULL,
3920                       RTNL_FLAG_DOIT_UNLOCKED);
3921         rtnl_register(PF_UNSPEC, RTM_GETTFILTER, tc_get_tfilter,
3922                       tc_dump_tfilter, RTNL_FLAG_DOIT_UNLOCKED);
3923         rtnl_register(PF_UNSPEC, RTM_NEWCHAIN, tc_ctl_chain, NULL, 0);
3924         rtnl_register(PF_UNSPEC, RTM_DELCHAIN, tc_ctl_chain, NULL, 0);
3925         rtnl_register(PF_UNSPEC, RTM_GETCHAIN, tc_ctl_chain,
3926                       tc_dump_chain, 0);
3927
3928         return 0;
3929
3930 err_register_pernet_subsys:
3931         destroy_workqueue(tc_filter_wq);
3932         return err;
3933 }
3934
3935 subsys_initcall(tc_filter_init);