net/sched/act_api.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * net/sched/act_api.c  Packet action API.
   4  *
   5  * Author:      Jamal Hadi Salim
   6  */
   7
   8 #include <linux/types.h>
   9 #include <linux/kernel.h>
  10 #include <linux/string.h>
  11 #include <linux/errno.h>
  12 #include <linux/slab.h>
  13 #include <linux/skbuff.h>
  14 #include <linux/init.h>
  15 #include <linux/kmod.h>
  16 #include <linux/err.h>
  17 #include <linux/module.h>
  18 #include <net/net_namespace.h>
  19 #include <net/sock.h>
  20 #include <net/sch_generic.h>
  21 #include <net/pkt_cls.h>
  22 #include <net/tc_act/tc_pedit.h>
  23 #include <net/act_api.h>
  24 #include <net/netlink.h>
  25 #include <net/flow_offload.h>
  26 #include <net/tc_wrapper.h>
  27
  28 #ifdef CONFIG_INET
  29 DEFINE_STATIC_KEY_FALSE(tcf_frag_xmit_count);
  30 EXPORT_SYMBOL_GPL(tcf_frag_xmit_count);
  31 #endif
  32
  33 int tcf_dev_queue_xmit(struct sk_buff *skb, int (*xmit)(struct sk_buff *skb))
  34 {
  35 #ifdef CONFIG_INET
  36         if (static_branch_unlikely(&tcf_frag_xmit_count))
  37                 return sch_frag_xmit_hook(skb, xmit);
  38 #endif
  39
  40         return xmit(skb);
  41 }
  42 EXPORT_SYMBOL_GPL(tcf_dev_queue_xmit);
  43
  44 static void tcf_action_goto_chain_exec(const struct tc_action *a,
  45                                        struct tcf_result *res)
  46 {
  47         const struct tcf_chain *chain = rcu_dereference_bh(a->goto_chain);
  48
  49         res->goto_tp = rcu_dereference_bh(chain->filter_chain);
  50 }
  51
  52 static void tcf_free_cookie_rcu(struct rcu_head *p)
  53 {
  54         struct tc_cookie *cookie = container_of(p, struct tc_cookie, rcu);
  55
  56         kfree(cookie->data);
  57         kfree(cookie);
  58 }
  59
  60 static void tcf_set_action_cookie(struct tc_cookie __rcu **old_cookie,
  61                                   struct tc_cookie *new_cookie)
  62 {
  63         struct tc_cookie *old;
  64
  65         old = xchg((__force struct tc_cookie **)old_cookie, new_cookie);
  66         if (old)
  67                 call_rcu(&old->rcu, tcf_free_cookie_rcu);
  68 }
  69
  70 int tcf_action_check_ctrlact(int action, struct tcf_proto *tp,
  71                              struct tcf_chain **newchain,
  72                              struct netlink_ext_ack *extack)
  73 {
  74         int opcode = TC_ACT_EXT_OPCODE(action), ret = -EINVAL;
  75         u32 chain_index;
  76
  77         if (!opcode)
  78                 ret = action > TC_ACT_VALUE_MAX ? -EINVAL : 0;
  79         else if (opcode <= TC_ACT_EXT_OPCODE_MAX || action == TC_ACT_UNSPEC)
  80                 ret = 0;
  81         if (ret) {
  82                 NL_SET_ERR_MSG(extack, "invalid control action");
  83                 goto end;
  84         }
  85
  86         if (TC_ACT_EXT_CMP(action, TC_ACT_GOTO_CHAIN)) {
  87                 chain_index = action & TC_ACT_EXT_VAL_MASK;
  88                 if (!tp || !newchain) {
  89                         ret = -EINVAL;
  90                         NL_SET_ERR_MSG(extack,
  91                                        "can't goto NULL proto/chain");
  92                         goto end;
  93                 }
  94                 *newchain = tcf_chain_get_by_act(tp->chain->block, chain_index);
  95                 if (!*newchain) {
  96                         ret = -ENOMEM;
  97                         NL_SET_ERR_MSG(extack,
  98                                        "can't allocate goto_chain");
  99                 }
 100         }
 101 end:
 102         return ret;
 103 }
 104 EXPORT_SYMBOL(tcf_action_check_ctrlact);
 105
 106 struct tcf_chain *tcf_action_set_ctrlact(struct tc_action *a, int action,
 107                                          struct tcf_chain *goto_chain)
 108 {
 109         a->tcfa_action = action;
 110         goto_chain = rcu_replace_pointer(a->goto_chain, goto_chain, 1);
 111         return goto_chain;
 112 }
 113 EXPORT_SYMBOL(tcf_action_set_ctrlact);
 114
 115 /* XXX: For standalone actions, we don't need a RCU grace period either, because
 116  * actions are always connected to filters and filters are already destroyed in
 117  * RCU callbacks, so after a RCU grace period actions are already disconnected
 118  * from filters. Readers later can not find us.
 119  */
 120 static void free_tcf(struct tc_action *p)
 121 {
 122         struct tcf_chain *chain = rcu_dereference_protected(p->goto_chain, 1);
 123
 124         free_percpu(p->cpu_bstats);
 125         free_percpu(p->cpu_bstats_hw);
 126         free_percpu(p->cpu_qstats);
 127
 128         tcf_set_action_cookie(&p->user_cookie, NULL);
 129         if (chain)
 130                 tcf_chain_put_by_act(chain);
 131
 132         kfree(p);
 133 }
 134
 135 static void offload_action_hw_count_set(struct tc_action *act,
 136                                         u32 hw_count)
 137 {
 138         act->in_hw_count = hw_count;
 139 }
 140
 141 static void offload_action_hw_count_inc(struct tc_action *act,
 142                                         u32 hw_count)
 143 {
 144         act->in_hw_count += hw_count;
 145 }
 146
 147 static void offload_action_hw_count_dec(struct tc_action *act,
 148                                         u32 hw_count)
 149 {
 150         act->in_hw_count = act->in_hw_count > hw_count ?
 151                            act->in_hw_count - hw_count : 0;
 152 }
 153
 154 static unsigned int tcf_offload_act_num_actions_single(struct tc_action *act)
 155 {
 156         if (is_tcf_pedit(act))
 157                 return tcf_pedit_nkeys(act);
 158         else
 159                 return 1;
 160 }
 161
 162 static bool tc_act_skip_hw(u32 flags)
 163 {
 164         return (flags & TCA_ACT_FLAGS_SKIP_HW) ? true : false;
 165 }
 166
 167 static bool tc_act_skip_sw(u32 flags)
 168 {
 169         return (flags & TCA_ACT_FLAGS_SKIP_SW) ? true : false;
 170 }
 171
 172 /* SKIP_HW and SKIP_SW are mutually exclusive flags. */
 173 static bool tc_act_flags_valid(u32 flags)
 174 {
 175         flags &= TCA_ACT_FLAGS_SKIP_HW | TCA_ACT_FLAGS_SKIP_SW;
 176
 177         return flags ^ (TCA_ACT_FLAGS_SKIP_HW | TCA_ACT_FLAGS_SKIP_SW);
 178 }
 179
 180 static int offload_action_init(struct flow_offload_action *fl_action,
 181                                struct tc_action *act,
 182                                enum offload_act_command  cmd,
 183                                struct netlink_ext_ack *extack)
 184 {
 185         int err;
 186
 187         fl_action->extack = extack;
 188         fl_action->command = cmd;
 189         fl_action->index = act->tcfa_index;
 190         fl_action->cookie = (unsigned long)act;
 191
 192         if (act->ops->offload_act_setup) {
 193                 spin_lock_bh(&act->tcfa_lock);
 194                 err = act->ops->offload_act_setup(act, fl_action, NULL,
 195                                                   false, extack);
 196                 spin_unlock_bh(&act->tcfa_lock);
 197                 return err;
 198         }
 199
 200         return -EOPNOTSUPP;
 201 }
 202
 203 static int tcf_action_offload_cmd_ex(struct flow_offload_action *fl_act,
 204                                      u32 *hw_count)
 205 {
 206         int err;
 207
 208         err = flow_indr_dev_setup_offload(NULL, NULL, TC_SETUP_ACT,
 209                                           fl_act, NULL, NULL);
 210         if (err < 0)
 211                 return err;
 212
 213         if (hw_count)
 214                 *hw_count = err;
 215
 216         return 0;
 217 }
 218
 219 static int tcf_action_offload_cmd_cb_ex(struct flow_offload_action *fl_act,
 220                                         u32 *hw_count,
 221                                         flow_indr_block_bind_cb_t *cb,
 222                                         void *cb_priv)
 223 {
 224         int err;
 225
 226         err = cb(NULL, NULL, cb_priv, TC_SETUP_ACT, NULL, fl_act, NULL);
 227         if (err < 0)
 228                 return err;
 229
 230         if (hw_count)
 231                 *hw_count = 1;
 232
 233         return 0;
 234 }
 235
 236 static int tcf_action_offload_cmd(struct flow_offload_action *fl_act,
 237                                   u32 *hw_count,
 238                                   flow_indr_block_bind_cb_t *cb,
 239                                   void *cb_priv)
 240 {
 241         return cb ? tcf_action_offload_cmd_cb_ex(fl_act, hw_count,
 242                                                  cb, cb_priv) :
 243                     tcf_action_offload_cmd_ex(fl_act, hw_count);
 244 }
 245
 246 static int tcf_action_offload_add_ex(struct tc_action *action,
 247                                      struct netlink_ext_ack *extack,
 248                                      flow_indr_block_bind_cb_t *cb,
 249                                      void *cb_priv)
 250 {
 251         bool skip_sw = tc_act_skip_sw(action->tcfa_flags);
 252         struct tc_action *actions[TCA_ACT_MAX_PRIO] = {
 253                 [0] = action,
 254         };
 255         struct flow_offload_action *fl_action;
 256         u32 in_hw_count = 0;
 257         int num, err = 0;
 258
 259         if (tc_act_skip_hw(action->tcfa_flags))
 260                 return 0;
 261
 262         num = tcf_offload_act_num_actions_single(action);
 263         fl_action = offload_action_alloc(num);
 264         if (!fl_action)
 265                 return -ENOMEM;
 266
 267         err = offload_action_init(fl_action, action, FLOW_ACT_REPLACE, extack);
 268         if (err)
 269                 goto fl_err;
 270
 271         err = tc_setup_action(&fl_action->action, actions, 0, extack);
 272         if (err) {
 273                 NL_SET_ERR_MSG_MOD(extack,
 274                                    "Failed to setup tc actions for offload");
 275                 goto fl_err;
 276         }
 277
 278         err = tcf_action_offload_cmd(fl_action, &in_hw_count, cb, cb_priv);
 279         if (!err)
 280                 cb ? offload_action_hw_count_inc(action, in_hw_count) :
 281                      offload_action_hw_count_set(action, in_hw_count);
 282
 283         if (skip_sw && !tc_act_in_hw(action))
 284                 err = -EINVAL;
 285
 286         tc_cleanup_offload_action(&fl_action->action);
 287
 288 fl_err:
 289         kfree(fl_action);
 290
 291         return err;
 292 }
 293
 294 /* offload the tc action after it is inserted */
 295 static int tcf_action_offload_add(struct tc_action *action,
 296                                   struct netlink_ext_ack *extack)
 297 {
 298         return tcf_action_offload_add_ex(action, extack, NULL, NULL);
 299 }
 300
 301 int tcf_action_update_hw_stats(struct tc_action *action)
 302 {
 303         struct flow_offload_action fl_act = {};
 304         int err;
 305
 306         err = offload_action_init(&fl_act, action, FLOW_ACT_STATS, NULL);
 307         if (err)
 308                 return err;
 309
 310         err = tcf_action_offload_cmd(&fl_act, NULL, NULL, NULL);
 311         if (!err) {
 312                 preempt_disable();
 313                 tcf_action_stats_update(action, fl_act.stats.bytes,
 314                                         fl_act.stats.pkts,
 315                                         fl_act.stats.drops,
 316                                         fl_act.stats.lastused,
 317                                         true);
 318                 preempt_enable();
 319                 action->used_hw_stats = fl_act.stats.used_hw_stats;
 320                 action->used_hw_stats_valid = true;
 321         } else {
 322                 return -EOPNOTSUPP;
 323         }
 324
 325         return 0;
 326 }
 327 EXPORT_SYMBOL(tcf_action_update_hw_stats);
 328
 329 static int tcf_action_offload_del_ex(struct tc_action *action,
 330                                      flow_indr_block_bind_cb_t *cb,
 331                                      void *cb_priv)
 332 {
 333         struct flow_offload_action fl_act = {};
 334         u32 in_hw_count = 0;
 335         int err = 0;
 336
 337         if (!tc_act_in_hw(action))
 338                 return 0;
 339
 340         err = offload_action_init(&fl_act, action, FLOW_ACT_DESTROY, NULL);
 341         if (err)
 342                 return err;
 343
 344         err = tcf_action_offload_cmd(&fl_act, &in_hw_count, cb, cb_priv);
 345         if (err < 0)
 346                 return err;
 347
 348         if (!cb && action->in_hw_count != in_hw_count)
 349                 return -EINVAL;
 350
 351         /* do not need to update hw state when deleting action */
 352         if (cb && in_hw_count)
 353                 offload_action_hw_count_dec(action, in_hw_count);
 354
 355         return 0;
 356 }
 357
 358 static int tcf_action_offload_del(struct tc_action *action)
 359 {
 360         return tcf_action_offload_del_ex(action, NULL, NULL);
 361 }
 362
 363 static void tcf_action_cleanup(struct tc_action *p)
 364 {
 365         tcf_action_offload_del(p);
 366         if (p->ops->cleanup)
 367                 p->ops->cleanup(p);
 368
 369         gen_kill_estimator(&p->tcfa_rate_est);
 370         free_tcf(p);
 371 }
 372
 373 static int __tcf_action_put(struct tc_action *p, bool bind)
 374 {
 375         struct tcf_idrinfo *idrinfo = p->idrinfo;
 376
 377         if (refcount_dec_and_mutex_lock(&p->tcfa_refcnt, &idrinfo->lock)) {
 378                 if (bind)
 379                         atomic_dec(&p->tcfa_bindcnt);
 380                 idr_remove(&idrinfo->action_idr, p->tcfa_index);
 381                 mutex_unlock(&idrinfo->lock);
 382
 383                 tcf_action_cleanup(p);
 384                 return 1;
 385         }
 386
 387         if (bind)
 388                 atomic_dec(&p->tcfa_bindcnt);
 389
 390         return 0;
 391 }
 392
 393 static int __tcf_idr_release(struct tc_action *p, bool bind, bool strict)
 394 {
 395         int ret = 0;
 396
 397         /* Release with strict==1 and bind==0 is only called through act API
 398          * interface (classifiers always bind). Only case when action with
 399          * positive reference count and zero bind count can exist is when it was
 400          * also created with act API (unbinding last classifier will destroy the
 401          * action if it was created by classifier). So only case when bind count
 402          * can be changed after initial check is when unbound action is
 403          * destroyed by act API while classifier binds to action with same id
 404          * concurrently. This result either creation of new action(same behavior
 405          * as before), or reusing existing action if concurrent process
 406          * increments reference count before action is deleted. Both scenarios
 407          * are acceptable.
 408          */
 409         if (p) {
 410                 if (!bind && strict && atomic_read(&p->tcfa_bindcnt) > 0)
 411                         return -EPERM;
 412
 413                 if (__tcf_action_put(p, bind))
 414                         ret = ACT_P_DELETED;
 415         }
 416
 417         return ret;
 418 }
 419
 420 int tcf_idr_release(struct tc_action *a, bool bind)
 421 {
 422         const struct tc_action_ops *ops = a->ops;
 423         int ret;
 424
 425         ret = __tcf_idr_release(a, bind, false);
 426         if (ret == ACT_P_DELETED)
 427                 module_put(ops->owner);
 428         return ret;
 429 }
 430 EXPORT_SYMBOL(tcf_idr_release);
 431
 432 static size_t tcf_action_shared_attrs_size(const struct tc_action *act)
 433 {
 434         struct tc_cookie *user_cookie;
 435         u32 cookie_len = 0;
 436
 437         rcu_read_lock();
 438         user_cookie = rcu_dereference(act->user_cookie);
 439
 440         if (user_cookie)
 441                 cookie_len = nla_total_size(user_cookie->len);
 442         rcu_read_unlock();
 443
 444         return  nla_total_size(0) /* action number nested */
 445                 + nla_total_size(IFNAMSIZ) /* TCA_ACT_KIND */
 446                 + cookie_len /* TCA_ACT_COOKIE */
 447                 + nla_total_size(sizeof(struct nla_bitfield32)) /* TCA_ACT_HW_STATS */
 448                 + nla_total_size(0) /* TCA_ACT_STATS nested */
 449                 + nla_total_size(sizeof(struct nla_bitfield32)) /* TCA_ACT_FLAGS */
 450                 /* TCA_STATS_BASIC */
 451                 + nla_total_size_64bit(sizeof(struct gnet_stats_basic))
 452                 /* TCA_STATS_PKT64 */
 453                 + nla_total_size_64bit(sizeof(u64))
 454                 /* TCA_STATS_QUEUE */
 455                 + nla_total_size_64bit(sizeof(struct gnet_stats_queue))
 456                 + nla_total_size(0) /* TCA_ACT_OPTIONS nested */
 457                 + nla_total_size(sizeof(struct tcf_t)); /* TCA_GACT_TM */
 458 }
 459
 460 static size_t tcf_action_full_attrs_size(size_t sz)
 461 {
 462         return NLMSG_HDRLEN                     /* struct nlmsghdr */
 463                 + sizeof(struct tcamsg)
 464                 + nla_total_size(0)             /* TCA_ACT_TAB nested */
 465                 + sz;
 466 }
 467
 468 static size_t tcf_action_fill_size(const struct tc_action *act)
 469 {
 470         size_t sz = tcf_action_shared_attrs_size(act);
 471
 472         if (act->ops->get_fill_size)
 473                 return act->ops->get_fill_size(act) + sz;
 474         return sz;
 475 }
 476
 477 static int
 478 tcf_action_dump_terse(struct sk_buff *skb, struct tc_action *a, bool from_act)
 479 {
 480         unsigned char *b = skb_tail_pointer(skb);
 481         struct tc_cookie *cookie;
 482
 483         if (nla_put_string(skb, TCA_ACT_KIND, a->ops->kind))
 484                 goto nla_put_failure;
 485         if (tcf_action_copy_stats(skb, a, 0))
 486                 goto nla_put_failure;
 487         if (from_act && nla_put_u32(skb, TCA_ACT_INDEX, a->tcfa_index))
 488                 goto nla_put_failure;
 489
 490         rcu_read_lock();
 491         cookie = rcu_dereference(a->user_cookie);
 492         if (cookie) {
 493                 if (nla_put(skb, TCA_ACT_COOKIE, cookie->len, cookie->data)) {
 494                         rcu_read_unlock();
 495                         goto nla_put_failure;
 496                 }
 497         }
 498         rcu_read_unlock();
 499
 500         return 0;
 501
 502 nla_put_failure:
 503         nlmsg_trim(skb, b);
 504         return -1;
 505 }
 506
 507 static int tcf_dump_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb,
 508                            struct netlink_callback *cb)
 509 {
 510         int err = 0, index = -1, s_i = 0, n_i = 0;
 511         u32 act_flags = cb->args[2];
 512         unsigned long jiffy_since = cb->args[3];
 513         struct nlattr *nest;
 514         struct idr *idr = &idrinfo->action_idr;
 515         struct tc_action *p;
 516         unsigned long id = 1;
 517         unsigned long tmp;
 518
 519         mutex_lock(&idrinfo->lock);
 520
 521         s_i = cb->args[0];
 522
 523         idr_for_each_entry_ul(idr, p, tmp, id) {
 524                 index++;
 525                 if (index < s_i)
 526                         continue;
 527                 if (IS_ERR(p))
 528                         continue;
 529
 530                 if (jiffy_since &&
 531                     time_after(jiffy_since,
 532                                (unsigned long)p->tcfa_tm.lastuse))
 533                         continue;
 534
 535                 tcf_action_update_hw_stats(p);
 536
 537                 nest = nla_nest_start_noflag(skb, n_i);
 538                 if (!nest) {
 539                         index--;
 540                         goto nla_put_failure;
 541                 }
 542                 err = (act_flags & TCA_ACT_FLAG_TERSE_DUMP) ?
 543                         tcf_action_dump_terse(skb, p, true) :
 544                         tcf_action_dump_1(skb, p, 0, 0);
 545                 if (err < 0) {
 546                         index--;
 547                         nlmsg_trim(skb, nest);
 548                         goto done;
 549                 }
 550                 nla_nest_end(skb, nest);
 551                 n_i++;
 552                 if (!(act_flags & TCA_ACT_FLAG_LARGE_DUMP_ON) &&
 553                     n_i >= TCA_ACT_MAX_PRIO)
 554                         goto done;
 555         }
 556 done:
 557         if (index >= 0)
 558                 cb->args[0] = index + 1;
 559
 560         mutex_unlock(&idrinfo->lock);
 561         if (n_i) {
 562                 if (act_flags & TCA_ACT_FLAG_LARGE_DUMP_ON)
 563                         cb->args[1] = n_i;
 564         }
 565         return n_i;
 566
 567 nla_put_failure:
 568         nla_nest_cancel(skb, nest);
 569         goto done;
 570 }
 571
 572 static int tcf_idr_release_unsafe(struct tc_action *p)
 573 {
 574         if (atomic_read(&p->tcfa_bindcnt) > 0)
 575                 return -EPERM;
 576
 577         if (refcount_dec_and_test(&p->tcfa_refcnt)) {
 578                 idr_remove(&p->idrinfo->action_idr, p->tcfa_index);
 579                 tcf_action_cleanup(p);
 580                 return ACT_P_DELETED;
 581         }
 582
 583         return 0;
 584 }
 585
 586 static int tcf_del_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb,
 587                           const struct tc_action_ops *ops,
 588                           struct netlink_ext_ack *extack)
 589 {
 590         struct nlattr *nest;
 591         int n_i = 0;
 592         int ret = -EINVAL;
 593         struct idr *idr = &idrinfo->action_idr;
 594         struct tc_action *p;
 595         unsigned long id = 1;
 596         unsigned long tmp;
 597
 598         nest = nla_nest_start_noflag(skb, 0);
 599         if (nest == NULL)
 600                 goto nla_put_failure;
 601         if (nla_put_string(skb, TCA_ACT_KIND, ops->kind))
 602                 goto nla_put_failure;
 603
 604         ret = 0;
 605         mutex_lock(&idrinfo->lock);
 606         idr_for_each_entry_ul(idr, p, tmp, id) {
 607                 if (IS_ERR(p))
 608                         continue;
 609                 ret = tcf_idr_release_unsafe(p);
 610                 if (ret == ACT_P_DELETED)
 611                         module_put(ops->owner);
 612                 else if (ret < 0)
 613                         break;
 614                 n_i++;
 615         }
 616         mutex_unlock(&idrinfo->lock);
 617         if (ret < 0) {
 618                 if (n_i)
 619                         NL_SET_ERR_MSG(extack, "Unable to flush all TC actions");
 620                 else
 621                         goto nla_put_failure;
 622         }
 623
 624         ret = nla_put_u32(skb, TCA_FCNT, n_i);
 625         if (ret)
 626                 goto nla_put_failure;
 627         nla_nest_end(skb, nest);
 628
 629         return n_i;
 630 nla_put_failure:
 631         nla_nest_cancel(skb, nest);
 632         return ret;
 633 }
 634
 635 int tcf_generic_walker(struct tc_action_net *tn, struct sk_buff *skb,
 636                        struct netlink_callback *cb, int type,
 637                        const struct tc_action_ops *ops,
 638                        struct netlink_ext_ack *extack)
 639 {
 640         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 641
 642         if (type == RTM_DELACTION) {
 643                 return tcf_del_walker(idrinfo, skb, ops, extack);
 644         } else if (type == RTM_GETACTION) {
 645                 return tcf_dump_walker(idrinfo, skb, cb);
 646         } else {
 647                 WARN(1, "tcf_generic_walker: unknown command %d\n", type);
 648                 NL_SET_ERR_MSG(extack, "tcf_generic_walker: unknown command");
 649                 return -EINVAL;
 650         }
 651 }
 652 EXPORT_SYMBOL(tcf_generic_walker);
 653
 654 int tcf_idr_search(struct tc_action_net *tn, struct tc_action **a, u32 index)
 655 {
 656         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 657         struct tc_action *p;
 658
 659         mutex_lock(&idrinfo->lock);
 660         p = idr_find(&idrinfo->action_idr, index);
 661         if (IS_ERR(p))
 662                 p = NULL;
 663         else if (p)
 664                 refcount_inc(&p->tcfa_refcnt);
 665         mutex_unlock(&idrinfo->lock);
 666
 667         if (p) {
 668                 *a = p;
 669                 return true;
 670         }
 671         return false;
 672 }
 673 EXPORT_SYMBOL(tcf_idr_search);
 674
 675 static int __tcf_generic_walker(struct net *net, struct sk_buff *skb,
 676                                 struct netlink_callback *cb, int type,
 677                                 const struct tc_action_ops *ops,
 678                                 struct netlink_ext_ack *extack)
 679 {
 680         struct tc_action_net *tn = net_generic(net, ops->net_id);
 681
 682         if (unlikely(ops->walk))
 683                 return ops->walk(net, skb, cb, type, ops, extack);
 684
 685         return tcf_generic_walker(tn, skb, cb, type, ops, extack);
 686 }
 687
 688 static int __tcf_idr_search(struct net *net,
 689                             const struct tc_action_ops *ops,
 690                             struct tc_action **a, u32 index)
 691 {
 692         struct tc_action_net *tn = net_generic(net, ops->net_id);
 693
 694         if (unlikely(ops->lookup))
 695                 return ops->lookup(net, a, index);
 696
 697         return tcf_idr_search(tn, a, index);
 698 }
 699
 700 static int tcf_idr_delete_index(struct tcf_idrinfo *idrinfo, u32 index)
 701 {
 702         struct tc_action *p;
 703         int ret = 0;
 704
 705         mutex_lock(&idrinfo->lock);
 706         p = idr_find(&idrinfo->action_idr, index);
 707         if (!p) {
 708                 mutex_unlock(&idrinfo->lock);
 709                 return -ENOENT;
 710         }
 711
 712         if (!atomic_read(&p->tcfa_bindcnt)) {
 713                 if (refcount_dec_and_test(&p->tcfa_refcnt)) {
 714                         struct module *owner = p->ops->owner;
 715
 716                         WARN_ON(p != idr_remove(&idrinfo->action_idr,
 717                                                 p->tcfa_index));
 718                         mutex_unlock(&idrinfo->lock);
 719
 720                         tcf_action_cleanup(p);
 721                         module_put(owner);
 722                         return 0;
 723                 }
 724                 ret = 0;
 725         } else {
 726                 ret = -EPERM;
 727         }
 728
 729         mutex_unlock(&idrinfo->lock);
 730         return ret;
 731 }
 732
 733 int tcf_idr_create(struct tc_action_net *tn, u32 index, struct nlattr *est,
 734                    struct tc_action **a, const struct tc_action_ops *ops,
 735                    int bind, bool cpustats, u32 flags)
 736 {
 737         struct tc_action *p = kzalloc(ops->size, GFP_KERNEL);
 738         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 739         int err = -ENOMEM;
 740
 741         if (unlikely(!p))
 742                 return -ENOMEM;
 743         refcount_set(&p->tcfa_refcnt, 1);
 744         if (bind)
 745                 atomic_set(&p->tcfa_bindcnt, 1);
 746
 747         if (cpustats) {
 748                 p->cpu_bstats = netdev_alloc_pcpu_stats(struct gnet_stats_basic_sync);
 749                 if (!p->cpu_bstats)
 750                         goto err1;
 751                 p->cpu_bstats_hw = netdev_alloc_pcpu_stats(struct gnet_stats_basic_sync);
 752                 if (!p->cpu_bstats_hw)
 753                         goto err2;
 754                 p->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
 755                 if (!p->cpu_qstats)
 756                         goto err3;
 757         }
 758         gnet_stats_basic_sync_init(&p->tcfa_bstats);
 759         gnet_stats_basic_sync_init(&p->tcfa_bstats_hw);
 760         spin_lock_init(&p->tcfa_lock);
 761         p->tcfa_index = index;
 762         p->tcfa_tm.install = jiffies;
 763         p->tcfa_tm.lastuse = jiffies;
 764         p->tcfa_tm.firstuse = 0;
 765         p->tcfa_flags = flags;
 766         if (est) {
 767                 err = gen_new_estimator(&p->tcfa_bstats, p->cpu_bstats,
 768                                         &p->tcfa_rate_est,
 769                                         &p->tcfa_lock, false, est);
 770                 if (err)
 771                         goto err4;
 772         }
 773
 774         p->idrinfo = idrinfo;
 775         __module_get(ops->owner);
 776         p->ops = ops;
 777         *a = p;
 778         return 0;
 779 err4:
 780         free_percpu(p->cpu_qstats);
 781 err3:
 782         free_percpu(p->cpu_bstats_hw);
 783 err2:
 784         free_percpu(p->cpu_bstats);
 785 err1:
 786         kfree(p);
 787         return err;
 788 }
 789 EXPORT_SYMBOL(tcf_idr_create);
 790
 791 int tcf_idr_create_from_flags(struct tc_action_net *tn, u32 index,
 792                               struct nlattr *est, struct tc_action **a,
 793                               const struct tc_action_ops *ops, int bind,
 794                               u32 flags)
 795 {
 796         /* Set cpustats according to actions flags. */
 797         return tcf_idr_create(tn, index, est, a, ops, bind,
 798                               !(flags & TCA_ACT_FLAGS_NO_PERCPU_STATS), flags);
 799 }
 800 EXPORT_SYMBOL(tcf_idr_create_from_flags);
 801
 802 /* Cleanup idr index that was allocated but not initialized. */
 803
 804 void tcf_idr_cleanup(struct tc_action_net *tn, u32 index)
 805 {
 806         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 807
 808         mutex_lock(&idrinfo->lock);
 809         /* Remove ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */
 810         WARN_ON(!IS_ERR(idr_remove(&idrinfo->action_idr, index)));
 811         mutex_unlock(&idrinfo->lock);
 812 }
 813 EXPORT_SYMBOL(tcf_idr_cleanup);
 814
 815 /* Check if action with specified index exists. If actions is found, increments
 816  * its reference and bind counters, and return 1. Otherwise insert temporary
 817  * error pointer (to prevent concurrent users from inserting actions with same
 818  * index) and return 0.
 819  */
 820
 821 int tcf_idr_check_alloc(struct tc_action_net *tn, u32 *index,
 822                         struct tc_action **a, int bind)
 823 {
 824         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 825         struct tc_action *p;
 826         int ret;
 827
 828 again:
 829         mutex_lock(&idrinfo->lock);
 830         if (*index) {
 831                 p = idr_find(&idrinfo->action_idr, *index);
 832                 if (IS_ERR(p)) {
 833                         /* This means that another process allocated
 834                          * index but did not assign the pointer yet.
 835                          */
 836                         mutex_unlock(&idrinfo->lock);
 837                         goto again;
 838                 }
 839
 840                 if (p) {
 841                         refcount_inc(&p->tcfa_refcnt);
 842                         if (bind)
 843                                 atomic_inc(&p->tcfa_bindcnt);
 844                         *a = p;
 845                         ret = 1;
 846                 } else {
 847                         *a = NULL;
 848                         ret = idr_alloc_u32(&idrinfo->action_idr, NULL, index,
 849                                             *index, GFP_KERNEL);
 850                         if (!ret)
 851                                 idr_replace(&idrinfo->action_idr,
 852                                             ERR_PTR(-EBUSY), *index);
 853                 }
 854         } else {
 855                 *index = 1;
 856                 *a = NULL;
 857                 ret = idr_alloc_u32(&idrinfo->action_idr, NULL, index,
 858                                     UINT_MAX, GFP_KERNEL);
 859                 if (!ret)
 860                         idr_replace(&idrinfo->action_idr, ERR_PTR(-EBUSY),
 861                                     *index);
 862         }
 863         mutex_unlock(&idrinfo->lock);
 864         return ret;
 865 }
 866 EXPORT_SYMBOL(tcf_idr_check_alloc);
 867
 868 void tcf_idrinfo_destroy(const struct tc_action_ops *ops,
 869                          struct tcf_idrinfo *idrinfo)
 870 {
 871         struct idr *idr = &idrinfo->action_idr;
 872         struct tc_action *p;
 873         int ret;
 874         unsigned long id = 1;
 875         unsigned long tmp;
 876
 877         idr_for_each_entry_ul(idr, p, tmp, id) {
 878                 ret = __tcf_idr_release(p, false, true);
 879                 if (ret == ACT_P_DELETED)
 880                         module_put(ops->owner);
 881                 else if (ret < 0)
 882                         return;
 883         }
 884         idr_destroy(&idrinfo->action_idr);
 885 }
 886 EXPORT_SYMBOL(tcf_idrinfo_destroy);
 887
 888 static LIST_HEAD(act_base);
 889 static DEFINE_RWLOCK(act_mod_lock);
 890 /* since act ops id is stored in pernet subsystem list,
 891  * then there is no way to walk through only all the action
 892  * subsystem, so we keep tc action pernet ops id for
 893  * reoffload to walk through.
 894  */
 895 static LIST_HEAD(act_pernet_id_list);
 896 static DEFINE_MUTEX(act_id_mutex);
 897 struct tc_act_pernet_id {
 898         struct list_head list;
 899         unsigned int id;
 900 };
 901
 902 static int tcf_pernet_add_id_list(unsigned int id)
 903 {
 904         struct tc_act_pernet_id *id_ptr;
 905         int ret = 0;
 906
 907         mutex_lock(&act_id_mutex);
 908         list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
 909                 if (id_ptr->id == id) {
 910                         ret = -EEXIST;
 911                         goto err_out;
 912                 }
 913         }
 914
 915         id_ptr = kzalloc(sizeof(*id_ptr), GFP_KERNEL);
 916         if (!id_ptr) {
 917                 ret = -ENOMEM;
 918                 goto err_out;
 919         }
 920         id_ptr->id = id;
 921
 922         list_add_tail(&id_ptr->list, &act_pernet_id_list);
 923
 924 err_out:
 925         mutex_unlock(&act_id_mutex);
 926         return ret;
 927 }
 928
 929 static void tcf_pernet_del_id_list(unsigned int id)
 930 {
 931         struct tc_act_pernet_id *id_ptr;
 932
 933         mutex_lock(&act_id_mutex);
 934         list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
 935                 if (id_ptr->id == id) {
 936                         list_del(&id_ptr->list);
 937                         kfree(id_ptr);
 938                         break;
 939                 }
 940         }
 941         mutex_unlock(&act_id_mutex);
 942 }
 943
 944 int tcf_register_action(struct tc_action_ops *act,
 945                         struct pernet_operations *ops)
 946 {
 947         struct tc_action_ops *a;
 948         int ret;
 949
 950         if (!act->act || !act->dump || !act->init)
 951                 return -EINVAL;
 952
 953         /* We have to register pernet ops before making the action ops visible,
 954          * otherwise tcf_action_init_1() could get a partially initialized
 955          * netns.
 956          */
 957         ret = register_pernet_subsys(ops);
 958         if (ret)
 959                 return ret;
 960
 961         if (ops->id) {
 962                 ret = tcf_pernet_add_id_list(*ops->id);
 963                 if (ret)
 964                         goto err_id;
 965         }
 966
 967         write_lock(&act_mod_lock);
 968         list_for_each_entry(a, &act_base, head) {
 969                 if (act->id == a->id || (strcmp(act->kind, a->kind) == 0)) {
 970                         ret = -EEXIST;
 971                         goto err_out;
 972                 }
 973         }
 974         list_add_tail(&act->head, &act_base);
 975         write_unlock(&act_mod_lock);
 976
 977         return 0;
 978
 979 err_out:
 980         write_unlock(&act_mod_lock);
 981         if (ops->id)
 982                 tcf_pernet_del_id_list(*ops->id);
 983 err_id:
 984         unregister_pernet_subsys(ops);
 985         return ret;
 986 }
 987 EXPORT_SYMBOL(tcf_register_action);
 988
 989 int tcf_unregister_action(struct tc_action_ops *act,
 990                           struct pernet_operations *ops)
 991 {
 992         struct tc_action_ops *a;
 993         int err = -ENOENT;
 994
 995         write_lock(&act_mod_lock);
 996         list_for_each_entry(a, &act_base, head) {
 997                 if (a == act) {
 998                         list_del(&act->head);
 999                         err = 0;
1000                         break;
1001                 }
1002         }
1003         write_unlock(&act_mod_lock);
1004         if (!err) {
1005                 unregister_pernet_subsys(ops);
1006                 if (ops->id)
1007                         tcf_pernet_del_id_list(*ops->id);
1008         }
1009         return err;
1010 }
1011 EXPORT_SYMBOL(tcf_unregister_action);
1012
1013 /* lookup by name */
1014 static struct tc_action_ops *tc_lookup_action_n(char *kind)
1015 {
1016         struct tc_action_ops *a, *res = NULL;
1017
1018         if (kind) {
1019                 read_lock(&act_mod_lock);
1020                 list_for_each_entry(a, &act_base, head) {
1021                         if (strcmp(kind, a->kind) == 0) {
1022                                 if (try_module_get(a->owner))
1023                                         res = a;
1024                                 break;
1025                         }
1026                 }
1027                 read_unlock(&act_mod_lock);
1028         }
1029         return res;
1030 }
1031
1032 /* lookup by nlattr */
1033 static struct tc_action_ops *tc_lookup_action(struct nlattr *kind)
1034 {
1035         struct tc_action_ops *a, *res = NULL;
1036
1037         if (kind) {
1038                 read_lock(&act_mod_lock);
1039                 list_for_each_entry(a, &act_base, head) {
1040                         if (nla_strcmp(kind, a->kind) == 0) {
1041                                 if (try_module_get(a->owner))
1042                                         res = a;
1043                                 break;
1044                         }
1045                 }
1046                 read_unlock(&act_mod_lock);
1047         }
1048         return res;
1049 }
1050
1051 /*TCA_ACT_MAX_PRIO is 32, there count up to 32 */
1052 #define TCA_ACT_MAX_PRIO_MASK 0x1FF
1053 int tcf_action_exec(struct sk_buff *skb, struct tc_action **actions,
1054                     int nr_actions, struct tcf_result *res)
1055 {
1056         u32 jmp_prgcnt = 0;
1057         u32 jmp_ttl = TCA_ACT_MAX_PRIO; /*matches actions per filter */
1058         int i;
1059         int ret = TC_ACT_OK;
1060
1061         if (skb_skip_tc_classify(skb))
1062                 return TC_ACT_OK;
1063
1064 restart_act_graph:
1065         for (i = 0; i < nr_actions; i++) {
1066                 const struct tc_action *a = actions[i];
1067                 int repeat_ttl;
1068
1069                 if (jmp_prgcnt > 0) {
1070                         jmp_prgcnt -= 1;
1071                         continue;
1072                 }
1073
1074                 if (tc_act_skip_sw(a->tcfa_flags))
1075                         continue;
1076
1077                 repeat_ttl = 32;
1078 repeat:
1079                 ret = tc_act(skb, a, res);
1080                 if (unlikely(ret == TC_ACT_REPEAT)) {
1081                         if (--repeat_ttl != 0)
1082                                 goto repeat;
1083                         /* suspicious opcode, stop pipeline */
1084                         net_warn_ratelimited("TC_ACT_REPEAT abuse ?\n");
1085                         return TC_ACT_OK;
1086                 }
1087                 if (TC_ACT_EXT_CMP(ret, TC_ACT_JUMP)) {
1088                         jmp_prgcnt = ret & TCA_ACT_MAX_PRIO_MASK;
1089                         if (!jmp_prgcnt || (jmp_prgcnt > nr_actions)) {
1090                                 /* faulty opcode, stop pipeline */
1091                                 return TC_ACT_OK;
1092                         } else {
1093                                 jmp_ttl -= 1;
1094                                 if (jmp_ttl > 0)
1095                                         goto restart_act_graph;
1096                                 else /* faulty graph, stop pipeline */
1097                                         return TC_ACT_OK;
1098                         }
1099                 } else if (TC_ACT_EXT_CMP(ret, TC_ACT_GOTO_CHAIN)) {
1100                         if (unlikely(!rcu_access_pointer(a->goto_chain))) {
1101                                 tcf_set_drop_reason(res, SKB_DROP_REASON_TC_ERROR);
1102                                 return TC_ACT_SHOT;
1103                         }
1104                         tcf_action_goto_chain_exec(a, res);
1105                 }
1106
1107                 if (ret != TC_ACT_PIPE)
1108                         break;
1109         }
1110
1111         return ret;
1112 }
1113 EXPORT_SYMBOL(tcf_action_exec);
1114
1115 int tcf_action_destroy(struct tc_action *actions[], int bind)
1116 {
1117         const struct tc_action_ops *ops;
1118         struct tc_action *a;
1119         int ret = 0, i;
1120
1121         for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
1122                 a = actions[i];
1123                 actions[i] = NULL;
1124                 ops = a->ops;
1125                 ret = __tcf_idr_release(a, bind, true);
1126                 if (ret == ACT_P_DELETED)
1127                         module_put(ops->owner);
1128                 else if (ret < 0)
1129                         return ret;
1130         }
1131         return ret;
1132 }
1133
1134 static int tcf_action_put(struct tc_action *p)
1135 {
1136         return __tcf_action_put(p, false);
1137 }
1138
1139 /* Put all actions in this array, skip those NULL's. */
1140 static void tcf_action_put_many(struct tc_action *actions[])
1141 {
1142         int i;
1143
1144         for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
1145                 struct tc_action *a = actions[i];
1146                 const struct tc_action_ops *ops;
1147
1148                 if (!a)
1149                         continue;
1150                 ops = a->ops;
1151                 if (tcf_action_put(a))
1152                         module_put(ops->owner);
1153         }
1154 }
1155
1156 int
1157 tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
1158 {
1159         return a->ops->dump(skb, a, bind, ref);
1160 }
1161
1162 int
1163 tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
1164 {
1165         int err = -EINVAL;
1166         unsigned char *b = skb_tail_pointer(skb);
1167         struct nlattr *nest;
1168         u32 flags;
1169
1170         if (tcf_action_dump_terse(skb, a, false))
1171                 goto nla_put_failure;
1172
1173         if (a->hw_stats != TCA_ACT_HW_STATS_ANY &&
1174             nla_put_bitfield32(skb, TCA_ACT_HW_STATS,
1175                                a->hw_stats, TCA_ACT_HW_STATS_ANY))
1176                 goto nla_put_failure;
1177
1178         if (a->used_hw_stats_valid &&
1179             nla_put_bitfield32(skb, TCA_ACT_USED_HW_STATS,
1180                                a->used_hw_stats, TCA_ACT_HW_STATS_ANY))
1181                 goto nla_put_failure;
1182
1183         flags = a->tcfa_flags & TCA_ACT_FLAGS_USER_MASK;
1184         if (flags &&
1185             nla_put_bitfield32(skb, TCA_ACT_FLAGS,
1186                                flags, flags))
1187                 goto nla_put_failure;
1188
1189         if (nla_put_u32(skb, TCA_ACT_IN_HW_COUNT, a->in_hw_count))
1190                 goto nla_put_failure;
1191
1192         nest = nla_nest_start_noflag(skb, TCA_ACT_OPTIONS);
1193         if (nest == NULL)
1194                 goto nla_put_failure;
1195         err = tcf_action_dump_old(skb, a, bind, ref);
1196         if (err > 0) {
1197                 nla_nest_end(skb, nest);
1198                 return err;
1199         }
1200
1201 nla_put_failure:
1202         nlmsg_trim(skb, b);
1203         return -1;
1204 }
1205 EXPORT_SYMBOL(tcf_action_dump_1);
1206
1207 int tcf_action_dump(struct sk_buff *skb, struct tc_action *actions[],
1208                     int bind, int ref, bool terse)
1209 {
1210         struct tc_action *a;
1211         int err = -EINVAL, i;
1212         struct nlattr *nest;
1213
1214         for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
1215                 a = actions[i];
1216                 nest = nla_nest_start_noflag(skb, i + 1);
1217                 if (nest == NULL)
1218                         goto nla_put_failure;
1219                 err = terse ? tcf_action_dump_terse(skb, a, false) :
1220                         tcf_action_dump_1(skb, a, bind, ref);
1221                 if (err < 0)
1222                         goto errout;
1223                 nla_nest_end(skb, nest);
1224         }
1225
1226         return 0;
1227
1228 nla_put_failure:
1229         err = -EINVAL;
1230 errout:
1231         nla_nest_cancel(skb, nest);
1232         return err;
1233 }
1234
1235 static struct tc_cookie *nla_memdup_cookie(struct nlattr **tb)
1236 {
1237         struct tc_cookie *c = kzalloc(sizeof(*c), GFP_KERNEL);
1238         if (!c)
1239                 return NULL;
1240
1241         c->data = nla_memdup(tb[TCA_ACT_COOKIE], GFP_KERNEL);
1242         if (!c->data) {
1243                 kfree(c);
1244                 return NULL;
1245         }
1246         c->len = nla_len(tb[TCA_ACT_COOKIE]);
1247
1248         return c;
1249 }
1250
1251 static u8 tcf_action_hw_stats_get(struct nlattr *hw_stats_attr)
1252 {
1253         struct nla_bitfield32 hw_stats_bf;
1254
1255         /* If the user did not pass the attr, that means he does
1256          * not care about the type. Return "any" in that case
1257          * which is setting on all supported types.
1258          */
1259         if (!hw_stats_attr)
1260                 return TCA_ACT_HW_STATS_ANY;
1261         hw_stats_bf = nla_get_bitfield32(hw_stats_attr);
1262         return hw_stats_bf.value;
1263 }
1264
1265 static const struct nla_policy tcf_action_policy[TCA_ACT_MAX + 1] = {
1266         [TCA_ACT_KIND]          = { .type = NLA_STRING },
1267         [TCA_ACT_INDEX]         = { .type = NLA_U32 },
1268         [TCA_ACT_COOKIE]        = { .type = NLA_BINARY,
1269                                     .len = TC_COOKIE_MAX_SIZE },
1270         [TCA_ACT_OPTIONS]       = { .type = NLA_NESTED },
1271         [TCA_ACT_FLAGS]         = NLA_POLICY_BITFIELD32(TCA_ACT_FLAGS_NO_PERCPU_STATS |
1272                                                         TCA_ACT_FLAGS_SKIP_HW |
1273                                                         TCA_ACT_FLAGS_SKIP_SW),
1274         [TCA_ACT_HW_STATS]      = NLA_POLICY_BITFIELD32(TCA_ACT_HW_STATS_ANY),
1275 };
1276
1277 void tcf_idr_insert_many(struct tc_action *actions[])
1278 {
1279         int i;
1280
1281         for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
1282                 struct tc_action *a = actions[i];
1283                 struct tcf_idrinfo *idrinfo;
1284
1285                 if (!a)
1286                         continue;
1287                 idrinfo = a->idrinfo;
1288                 mutex_lock(&idrinfo->lock);
1289                 /* Replace ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc if
1290                  * it is just created, otherwise this is just a nop.
1291                  */
1292                 idr_replace(&idrinfo->action_idr, a, a->tcfa_index);
1293                 mutex_unlock(&idrinfo->lock);
1294         }
1295 }
1296
1297 struct tc_action_ops *tc_action_load_ops(struct nlattr *nla, bool police,
1298                                          bool rtnl_held,
1299                                          struct netlink_ext_ack *extack)
1300 {
1301         struct nlattr *tb[TCA_ACT_MAX + 1];
1302         struct tc_action_ops *a_o;
1303         char act_name[IFNAMSIZ];
1304         struct nlattr *kind;
1305         int err;
1306
1307         if (!police) {
1308                 err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1309                                                   tcf_action_policy, extack);
1310                 if (err < 0)
1311                         return ERR_PTR(err);
1312                 err = -EINVAL;
1313                 kind = tb[TCA_ACT_KIND];
1314                 if (!kind) {
1315                         NL_SET_ERR_MSG(extack, "TC action kind must be specified");
1316                         return ERR_PTR(err);
1317                 }
1318                 if (nla_strscpy(act_name, kind, IFNAMSIZ) < 0) {
1319                         NL_SET_ERR_MSG(extack, "TC action name too long");
1320                         return ERR_PTR(err);
1321                 }
1322         } else {
1323                 if (strscpy(act_name, "police", IFNAMSIZ) < 0) {
1324                         NL_SET_ERR_MSG(extack, "TC action name too long");
1325                         return ERR_PTR(-EINVAL);
1326                 }
1327         }
1328
1329         a_o = tc_lookup_action_n(act_name);
1330         if (a_o == NULL) {
1331 #ifdef CONFIG_MODULES
1332                 if (rtnl_held)
1333                         rtnl_unlock();
1334                 request_module("act_%s", act_name);
1335                 if (rtnl_held)
1336                         rtnl_lock();
1337
1338                 a_o = tc_lookup_action_n(act_name);
1339
1340                 /* We dropped the RTNL semaphore in order to
1341                  * perform the module load.  So, even if we
1342                  * succeeded in loading the module we have to
1343                  * tell the caller to replay the request.  We
1344                  * indicate this using -EAGAIN.
1345                  */
1346                 if (a_o != NULL) {
1347                         module_put(a_o->owner);
1348                         return ERR_PTR(-EAGAIN);
1349                 }
1350 #endif
1351                 NL_SET_ERR_MSG(extack, "Failed to load TC action module");
1352                 return ERR_PTR(-ENOENT);
1353         }
1354
1355         return a_o;
1356 }
1357
1358 struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
1359                                     struct nlattr *nla, struct nlattr *est,
1360                                     struct tc_action_ops *a_o, int *init_res,
1361                                     u32 flags, struct netlink_ext_ack *extack)
1362 {
1363         bool police = flags & TCA_ACT_FLAGS_POLICE;
1364         struct nla_bitfield32 userflags = { 0, 0 };
1365         struct tc_cookie *user_cookie = NULL;
1366         u8 hw_stats = TCA_ACT_HW_STATS_ANY;
1367         struct nlattr *tb[TCA_ACT_MAX + 1];
1368         struct tc_action *a;
1369         int err;
1370
1371         /* backward compatibility for policer */
1372         if (!police) {
1373                 err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1374                                                   tcf_action_policy, extack);
1375                 if (err < 0)
1376                         return ERR_PTR(err);
1377                 if (tb[TCA_ACT_COOKIE]) {
1378                         user_cookie = nla_memdup_cookie(tb);
1379                         if (!user_cookie) {
1380                                 NL_SET_ERR_MSG(extack, "No memory to generate TC cookie");
1381                                 err = -ENOMEM;
1382                                 goto err_out;
1383                         }
1384                 }
1385                 hw_stats = tcf_action_hw_stats_get(tb[TCA_ACT_HW_STATS]);
1386                 if (tb[TCA_ACT_FLAGS]) {
1387                         userflags = nla_get_bitfield32(tb[TCA_ACT_FLAGS]);
1388                         if (!tc_act_flags_valid(userflags.value)) {
1389                                 err = -EINVAL;
1390                                 goto err_out;
1391                         }
1392                 }
1393
1394                 err = a_o->init(net, tb[TCA_ACT_OPTIONS], est, &a, tp,
1395                                 userflags.value | flags, extack);
1396         } else {
1397                 err = a_o->init(net, nla, est, &a, tp, userflags.value | flags,
1398                                 extack);
1399         }
1400         if (err < 0)
1401                 goto err_out;
1402         *init_res = err;
1403
1404         if (!police && tb[TCA_ACT_COOKIE])
1405                 tcf_set_action_cookie(&a->user_cookie, user_cookie);
1406
1407         if (!police)
1408                 a->hw_stats = hw_stats;
1409
1410         return a;
1411
1412 err_out:
1413         if (user_cookie) {
1414                 kfree(user_cookie->data);
1415                 kfree(user_cookie);
1416         }
1417         return ERR_PTR(err);
1418 }
1419
1420 static bool tc_act_bind(u32 flags)
1421 {
1422         return !!(flags & TCA_ACT_FLAGS_BIND);
1423 }
1424
1425 /* Returns numbers of initialized actions or negative error. */
1426
1427 int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla,
1428                     struct nlattr *est, struct tc_action *actions[],
1429                     int init_res[], size_t *attr_size,
1430                     u32 flags, u32 fl_flags,
1431                     struct netlink_ext_ack *extack)
1432 {
1433         struct tc_action_ops *ops[TCA_ACT_MAX_PRIO] = {};
1434         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1435         struct tc_action *act;
1436         size_t sz = 0;
1437         int err;
1438         int i;
1439
1440         err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX_PRIO, nla, NULL,
1441                                           extack);
1442         if (err < 0)
1443                 return err;
1444
1445         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1446                 struct tc_action_ops *a_o;
1447
1448                 a_o = tc_action_load_ops(tb[i], flags & TCA_ACT_FLAGS_POLICE,
1449                                          !(flags & TCA_ACT_FLAGS_NO_RTNL),
1450                                          extack);
1451                 if (IS_ERR(a_o)) {
1452                         err = PTR_ERR(a_o);
1453                         goto err_mod;
1454                 }
1455                 ops[i - 1] = a_o;
1456         }
1457
1458         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1459                 act = tcf_action_init_1(net, tp, tb[i], est, ops[i - 1],
1460                                         &init_res[i - 1], flags, extack);
1461                 if (IS_ERR(act)) {
1462                         err = PTR_ERR(act);
1463                         goto err;
1464                 }
1465                 sz += tcf_action_fill_size(act);
1466                 /* Start from index 0 */
1467                 actions[i - 1] = act;
1468                 if (tc_act_bind(flags)) {
1469                         bool skip_sw = tc_skip_sw(fl_flags);
1470                         bool skip_hw = tc_skip_hw(fl_flags);
1471
1472                         if (tc_act_bind(act->tcfa_flags))
1473                                 continue;
1474                         if (skip_sw != tc_act_skip_sw(act->tcfa_flags) ||
1475                             skip_hw != tc_act_skip_hw(act->tcfa_flags)) {
1476                                 NL_SET_ERR_MSG(extack,
1477                                                "Mismatch between action and filter offload flags");
1478                                 err = -EINVAL;
1479                                 goto err;
1480                         }
1481                 } else {
1482                         err = tcf_action_offload_add(act, extack);
1483                         if (tc_act_skip_sw(act->tcfa_flags) && err)
1484                                 goto err;
1485                 }
1486         }
1487
1488         /* We have to commit them all together, because if any error happened in
1489          * between, we could not handle the failure gracefully.
1490          */
1491         tcf_idr_insert_many(actions);
1492
1493         *attr_size = tcf_action_full_attrs_size(sz);
1494         err = i - 1;
1495         goto err_mod;
1496
1497 err:
1498         tcf_action_destroy(actions, flags & TCA_ACT_FLAGS_BIND);
1499 err_mod:
1500         for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
1501                 if (ops[i])
1502                         module_put(ops[i]->owner);
1503         }
1504         return err;
1505 }
1506
1507 void tcf_action_update_stats(struct tc_action *a, u64 bytes, u64 packets,
1508                              u64 drops, bool hw)
1509 {
1510         if (a->cpu_bstats) {
1511                 _bstats_update(this_cpu_ptr(a->cpu_bstats), bytes, packets);
1512
1513                 this_cpu_ptr(a->cpu_qstats)->drops += drops;
1514
1515                 if (hw)
1516                         _bstats_update(this_cpu_ptr(a->cpu_bstats_hw),
1517                                        bytes, packets);
1518                 return;
1519         }
1520
1521         _bstats_update(&a->tcfa_bstats, bytes, packets);
1522         a->tcfa_qstats.drops += drops;
1523         if (hw)
1524                 _bstats_update(&a->tcfa_bstats_hw, bytes, packets);
1525 }
1526 EXPORT_SYMBOL(tcf_action_update_stats);
1527
1528 int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *p,
1529                           int compat_mode)
1530 {
1531         int err = 0;
1532         struct gnet_dump d;
1533
1534         if (p == NULL)
1535                 goto errout;
1536
1537         /* compat_mode being true specifies a call that is supposed
1538          * to add additional backward compatibility statistic TLVs.
1539          */
1540         if (compat_mode) {
1541                 if (p->type == TCA_OLD_COMPAT)
1542                         err = gnet_stats_start_copy_compat(skb, 0,
1543                                                            TCA_STATS,
1544                                                            TCA_XSTATS,
1545                                                            &p->tcfa_lock, &d,
1546                                                            TCA_PAD);
1547                 else
1548                         return 0;
1549         } else
1550                 err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
1551                                             &p->tcfa_lock, &d, TCA_ACT_PAD);
1552
1553         if (err < 0)
1554                 goto errout;
1555
1556         if (gnet_stats_copy_basic(&d, p->cpu_bstats,
1557                                   &p->tcfa_bstats, false) < 0 ||
1558             gnet_stats_copy_basic_hw(&d, p->cpu_bstats_hw,
1559                                      &p->tcfa_bstats_hw, false) < 0 ||
1560             gnet_stats_copy_rate_est(&d, &p->tcfa_rate_est) < 0 ||
1561             gnet_stats_copy_queue(&d, p->cpu_qstats,
1562                                   &p->tcfa_qstats,
1563                                   p->tcfa_qstats.qlen) < 0)
1564                 goto errout;
1565
1566         if (gnet_stats_finish_copy(&d) < 0)
1567                 goto errout;
1568
1569         return 0;
1570
1571 errout:
1572         return -1;
1573 }
1574
1575 static int tca_get_fill(struct sk_buff *skb, struct tc_action *actions[],
1576                         u32 portid, u32 seq, u16 flags, int event, int bind,
1577                         int ref, struct netlink_ext_ack *extack)
1578 {
1579         struct tcamsg *t;
1580         struct nlmsghdr *nlh;
1581         unsigned char *b = skb_tail_pointer(skb);
1582         struct nlattr *nest;
1583
1584         nlh = nlmsg_put(skb, portid, seq, event, sizeof(*t), flags);
1585         if (!nlh)
1586                 goto out_nlmsg_trim;
1587         t = nlmsg_data(nlh);
1588         t->tca_family = AF_UNSPEC;
1589         t->tca__pad1 = 0;
1590         t->tca__pad2 = 0;
1591
1592         if (extack && extack->_msg &&
1593             nla_put_string(skb, TCA_ROOT_EXT_WARN_MSG, extack->_msg))
1594                 goto out_nlmsg_trim;
1595
1596         nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
1597         if (!nest)
1598                 goto out_nlmsg_trim;
1599
1600         if (tcf_action_dump(skb, actions, bind, ref, false) < 0)
1601                 goto out_nlmsg_trim;
1602
1603         nla_nest_end(skb, nest);
1604
1605         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1606
1607         return skb->len;
1608
1609 out_nlmsg_trim:
1610         nlmsg_trim(skb, b);
1611         return -1;
1612 }
1613
1614 static int
1615 tcf_get_notify(struct net *net, u32 portid, struct nlmsghdr *n,
1616                struct tc_action *actions[], int event,
1617                struct netlink_ext_ack *extack)
1618 {
1619         struct sk_buff *skb;
1620
1621         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1622         if (!skb)
1623                 return -ENOBUFS;
1624         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, event,
1625                          0, 1, NULL) <= 0) {
1626                 NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1627                 kfree_skb(skb);
1628                 return -EINVAL;
1629         }
1630
1631         return rtnl_unicast(skb, net, portid);
1632 }
1633
1634 static struct tc_action *tcf_action_get_1(struct net *net, struct nlattr *nla,
1635                                           struct nlmsghdr *n, u32 portid,
1636                                           struct netlink_ext_ack *extack)
1637 {
1638         struct nlattr *tb[TCA_ACT_MAX + 1];
1639         const struct tc_action_ops *ops;
1640         struct tc_action *a;
1641         int index;
1642         int err;
1643
1644         err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1645                                           tcf_action_policy, extack);
1646         if (err < 0)
1647                 goto err_out;
1648
1649         err = -EINVAL;
1650         if (tb[TCA_ACT_INDEX] == NULL ||
1651             nla_len(tb[TCA_ACT_INDEX]) < sizeof(index)) {
1652                 NL_SET_ERR_MSG(extack, "Invalid TC action index value");
1653                 goto err_out;
1654         }
1655         index = nla_get_u32(tb[TCA_ACT_INDEX]);
1656
1657         err = -EINVAL;
1658         ops = tc_lookup_action(tb[TCA_ACT_KIND]);
1659         if (!ops) { /* could happen in batch of actions */
1660                 NL_SET_ERR_MSG(extack, "Specified TC action kind not found");
1661                 goto err_out;
1662         }
1663         err = -ENOENT;
1664         if (__tcf_idr_search(net, ops, &a, index) == 0) {
1665                 NL_SET_ERR_MSG(extack, "TC action with specified index not found");
1666                 goto err_mod;
1667         }
1668
1669         module_put(ops->owner);
1670         return a;
1671
1672 err_mod:
1673         module_put(ops->owner);
1674 err_out:
1675         return ERR_PTR(err);
1676 }
1677
1678 static int tca_action_flush(struct net *net, struct nlattr *nla,
1679                             struct nlmsghdr *n, u32 portid,
1680                             struct netlink_ext_ack *extack)
1681 {
1682         struct sk_buff *skb;
1683         unsigned char *b;
1684         struct nlmsghdr *nlh;
1685         struct tcamsg *t;
1686         struct netlink_callback dcb;
1687         struct nlattr *nest;
1688         struct nlattr *tb[TCA_ACT_MAX + 1];
1689         const struct tc_action_ops *ops;
1690         struct nlattr *kind;
1691         int err = -ENOMEM;
1692
1693         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1694         if (!skb)
1695                 return err;
1696
1697         b = skb_tail_pointer(skb);
1698
1699         err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1700                                           tcf_action_policy, extack);
1701         if (err < 0)
1702                 goto err_out;
1703
1704         err = -EINVAL;
1705         kind = tb[TCA_ACT_KIND];
1706         ops = tc_lookup_action(kind);
1707         if (!ops) { /*some idjot trying to flush unknown action */
1708                 NL_SET_ERR_MSG(extack, "Cannot flush unknown TC action");
1709                 goto err_out;
1710         }
1711
1712         nlh = nlmsg_put(skb, portid, n->nlmsg_seq, RTM_DELACTION,
1713                         sizeof(*t), 0);
1714         if (!nlh) {
1715                 NL_SET_ERR_MSG(extack, "Failed to create TC action flush notification");
1716                 goto out_module_put;
1717         }
1718         t = nlmsg_data(nlh);
1719         t->tca_family = AF_UNSPEC;
1720         t->tca__pad1 = 0;
1721         t->tca__pad2 = 0;
1722
1723         nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
1724         if (!nest) {
1725                 NL_SET_ERR_MSG(extack, "Failed to add new netlink message");
1726                 goto out_module_put;
1727         }
1728
1729         err = __tcf_generic_walker(net, skb, &dcb, RTM_DELACTION, ops, extack);
1730         if (err <= 0) {
1731                 nla_nest_cancel(skb, nest);
1732                 goto out_module_put;
1733         }
1734
1735         nla_nest_end(skb, nest);
1736
1737         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1738         nlh->nlmsg_flags |= NLM_F_ROOT;
1739         module_put(ops->owner);
1740         err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1741                              n->nlmsg_flags & NLM_F_ECHO);
1742         if (err < 0)
1743                 NL_SET_ERR_MSG(extack, "Failed to send TC action flush notification");
1744
1745         return err;
1746
1747 out_module_put:
1748         module_put(ops->owner);
1749 err_out:
1750         kfree_skb(skb);
1751         return err;
1752 }
1753
1754 static int tcf_action_delete(struct net *net, struct tc_action *actions[])
1755 {
1756         int i;
1757
1758         for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
1759                 struct tc_action *a = actions[i];
1760                 const struct tc_action_ops *ops = a->ops;
1761                 /* Actions can be deleted concurrently so we must save their
1762                  * type and id to search again after reference is released.
1763                  */
1764                 struct tcf_idrinfo *idrinfo = a->idrinfo;
1765                 u32 act_index = a->tcfa_index;
1766
1767                 actions[i] = NULL;
1768                 if (tcf_action_put(a)) {
1769                         /* last reference, action was deleted concurrently */
1770                         module_put(ops->owner);
1771                 } else  {
1772                         int ret;
1773
1774                         /* now do the delete */
1775                         ret = tcf_idr_delete_index(idrinfo, act_index);
1776                         if (ret < 0)
1777                                 return ret;
1778                 }
1779         }
1780         return 0;
1781 }
1782
1783 static int
1784 tcf_reoffload_del_notify(struct net *net, struct tc_action *action)
1785 {
1786         size_t attr_size = tcf_action_fill_size(action);
1787         struct tc_action *actions[TCA_ACT_MAX_PRIO] = {
1788                 [0] = action,
1789         };
1790         const struct tc_action_ops *ops = action->ops;
1791         struct sk_buff *skb;
1792         int ret;
1793
1794         skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1795                         GFP_KERNEL);
1796         if (!skb)
1797                 return -ENOBUFS;
1798
1799         if (tca_get_fill(skb, actions, 0, 0, 0, RTM_DELACTION, 0, 1, NULL) <= 0) {
1800                 kfree_skb(skb);
1801                 return -EINVAL;
1802         }
1803
1804         ret = tcf_idr_release_unsafe(action);
1805         if (ret == ACT_P_DELETED) {
1806                 module_put(ops->owner);
1807                 ret = rtnetlink_send(skb, net, 0, RTNLGRP_TC, 0);
1808         } else {
1809                 kfree_skb(skb);
1810         }
1811
1812         return ret;
1813 }
1814
1815 int tcf_action_reoffload_cb(flow_indr_block_bind_cb_t *cb,
1816                             void *cb_priv, bool add)
1817 {
1818         struct tc_act_pernet_id *id_ptr;
1819         struct tcf_idrinfo *idrinfo;
1820         struct tc_action_net *tn;
1821         struct tc_action *p;
1822         unsigned int act_id;
1823         unsigned long tmp;
1824         unsigned long id;
1825         struct idr *idr;
1826         struct net *net;
1827         int ret;
1828
1829         if (!cb)
1830                 return -EINVAL;
1831
1832         down_read(&net_rwsem);
1833         mutex_lock(&act_id_mutex);
1834
1835         for_each_net(net) {
1836                 list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
1837                         act_id = id_ptr->id;
1838                         tn = net_generic(net, act_id);
1839                         if (!tn)
1840                                 continue;
1841                         idrinfo = tn->idrinfo;
1842                         if (!idrinfo)
1843                                 continue;
1844
1845                         mutex_lock(&idrinfo->lock);
1846                         idr = &idrinfo->action_idr;
1847                         idr_for_each_entry_ul(idr, p, tmp, id) {
1848                                 if (IS_ERR(p) || tc_act_bind(p->tcfa_flags))
1849                                         continue;
1850                                 if (add) {
1851                                         tcf_action_offload_add_ex(p, NULL, cb,
1852                                                                   cb_priv);
1853                                         continue;
1854                                 }
1855
1856                                 /* cb unregister to update hw count */
1857                                 ret = tcf_action_offload_del_ex(p, cb, cb_priv);
1858                                 if (ret < 0)
1859                                         continue;
1860                                 if (tc_act_skip_sw(p->tcfa_flags) &&
1861                                     !tc_act_in_hw(p))
1862                                         tcf_reoffload_del_notify(net, p);
1863                         }
1864                         mutex_unlock(&idrinfo->lock);
1865                 }
1866         }
1867         mutex_unlock(&act_id_mutex);
1868         up_read(&net_rwsem);
1869
1870         return 0;
1871 }
1872
1873 static int
1874 tcf_del_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[],
1875                u32 portid, size_t attr_size, struct netlink_ext_ack *extack)
1876 {
1877         int ret;
1878         struct sk_buff *skb;
1879
1880         skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1881                         GFP_KERNEL);
1882         if (!skb)
1883                 return -ENOBUFS;
1884
1885         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, RTM_DELACTION,
1886                          0, 2, extack) <= 0) {
1887                 NL_SET_ERR_MSG(extack, "Failed to fill netlink TC action attributes");
1888                 kfree_skb(skb);
1889                 return -EINVAL;
1890         }
1891
1892         /* now do the delete */
1893         ret = tcf_action_delete(net, actions);
1894         if (ret < 0) {
1895                 NL_SET_ERR_MSG(extack, "Failed to delete TC action");
1896                 kfree_skb(skb);
1897                 return ret;
1898         }
1899
1900         ret = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1901                              n->nlmsg_flags & NLM_F_ECHO);
1902         return ret;
1903 }
1904
1905 static int
1906 tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
1907               u32 portid, int event, struct netlink_ext_ack *extack)
1908 {
1909         int i, ret;
1910         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1911         struct tc_action *act;
1912         size_t attr_size = 0;
1913         struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
1914
1915         ret = nla_parse_nested_deprecated(tb, TCA_ACT_MAX_PRIO, nla, NULL,
1916                                           extack);
1917         if (ret < 0)
1918                 return ret;
1919
1920         if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) {
1921                 if (tb[1])
1922                         return tca_action_flush(net, tb[1], n, portid, extack);
1923
1924                 NL_SET_ERR_MSG(extack, "Invalid netlink attributes while flushing TC action");
1925                 return -EINVAL;
1926         }
1927
1928         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1929                 act = tcf_action_get_1(net, tb[i], n, portid, extack);
1930                 if (IS_ERR(act)) {
1931                         ret = PTR_ERR(act);
1932                         goto err;
1933                 }
1934                 attr_size += tcf_action_fill_size(act);
1935                 actions[i - 1] = act;
1936         }
1937
1938         attr_size = tcf_action_full_attrs_size(attr_size);
1939
1940         if (event == RTM_GETACTION)
1941                 ret = tcf_get_notify(net, portid, n, actions, event, extack);
1942         else { /* delete */
1943                 ret = tcf_del_notify(net, n, actions, portid, attr_size, extack);
1944                 if (ret)
1945                         goto err;
1946                 return 0;
1947         }
1948 err:
1949         tcf_action_put_many(actions);
1950         return ret;
1951 }
1952
1953 static int
1954 tcf_add_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[],
1955                u32 portid, size_t attr_size, struct netlink_ext_ack *extack)
1956 {
1957         struct sk_buff *skb;
1958
1959         skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1960                         GFP_KERNEL);
1961         if (!skb)
1962                 return -ENOBUFS;
1963
1964         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, n->nlmsg_flags,
1965                          RTM_NEWACTION, 0, 0, extack) <= 0) {
1966                 NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1967                 kfree_skb(skb);
1968                 return -EINVAL;
1969         }
1970
1971         return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1972                               n->nlmsg_flags & NLM_F_ECHO);
1973 }
1974
1975 static int tcf_action_add(struct net *net, struct nlattr *nla,
1976                           struct nlmsghdr *n, u32 portid, u32 flags,
1977                           struct netlink_ext_ack *extack)
1978 {
1979         size_t attr_size = 0;
1980         int loop, ret, i;
1981         struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
1982         int init_res[TCA_ACT_MAX_PRIO] = {};
1983
1984         for (loop = 0; loop < 10; loop++) {
1985                 ret = tcf_action_init(net, NULL, nla, NULL, actions, init_res,
1986                                       &attr_size, flags, 0, extack);
1987                 if (ret != -EAGAIN)
1988                         break;
1989         }
1990
1991         if (ret < 0)
1992                 return ret;
1993         ret = tcf_add_notify(net, n, actions, portid, attr_size, extack);
1994
1995         /* only put existing actions */
1996         for (i = 0; i < TCA_ACT_MAX_PRIO; i++)
1997                 if (init_res[i] == ACT_P_CREATED)
1998                         actions[i] = NULL;
1999         tcf_action_put_many(actions);
2000
2001         return ret;
2002 }
2003
2004 static const struct nla_policy tcaa_policy[TCA_ROOT_MAX + 1] = {
2005         [TCA_ROOT_FLAGS] = NLA_POLICY_BITFIELD32(TCA_ACT_FLAG_LARGE_DUMP_ON |
2006                                                  TCA_ACT_FLAG_TERSE_DUMP),
2007         [TCA_ROOT_TIME_DELTA]      = { .type = NLA_U32 },
2008 };
2009
2010 static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n,
2011                          struct netlink_ext_ack *extack)
2012 {
2013         struct net *net = sock_net(skb->sk);
2014         struct nlattr *tca[TCA_ROOT_MAX + 1];
2015         u32 portid = NETLINK_CB(skb).portid;
2016         u32 flags = 0;
2017         int ret = 0;
2018
2019         if ((n->nlmsg_type != RTM_GETACTION) &&
2020             !netlink_capable(skb, CAP_NET_ADMIN))
2021                 return -EPERM;
2022
2023         ret = nlmsg_parse_deprecated(n, sizeof(struct tcamsg), tca,
2024                                      TCA_ROOT_MAX, NULL, extack);
2025         if (ret < 0)
2026                 return ret;
2027
2028         if (tca[TCA_ACT_TAB] == NULL) {
2029                 NL_SET_ERR_MSG(extack, "Netlink action attributes missing");
2030                 return -EINVAL;
2031         }
2032
2033         /* n->nlmsg_flags & NLM_F_CREATE */
2034         switch (n->nlmsg_type) {
2035         case RTM_NEWACTION:
2036                 /* we are going to assume all other flags
2037                  * imply create only if it doesn't exist
2038                  * Note that CREATE | EXCL implies that
2039                  * but since we want avoid ambiguity (eg when flags
2040                  * is zero) then just set this
2041                  */
2042                 if (n->nlmsg_flags & NLM_F_REPLACE)
2043                         flags = TCA_ACT_FLAGS_REPLACE;
2044                 ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, portid, flags,
2045                                      extack);
2046                 break;
2047         case RTM_DELACTION:
2048                 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
2049                                     portid, RTM_DELACTION, extack);
2050                 break;
2051         case RTM_GETACTION:
2052                 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
2053                                     portid, RTM_GETACTION, extack);
2054                 break;
2055         default:
2056                 BUG();
2057         }
2058
2059         return ret;
2060 }
2061
2062 static struct nlattr *find_dump_kind(struct nlattr **nla)
2063 {
2064         struct nlattr *tb1, *tb2[TCA_ACT_MAX + 1];
2065         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
2066         struct nlattr *kind;
2067
2068         tb1 = nla[TCA_ACT_TAB];
2069         if (tb1 == NULL)
2070                 return NULL;
2071
2072         if (nla_parse_deprecated(tb, TCA_ACT_MAX_PRIO, nla_data(tb1), NLMSG_ALIGN(nla_len(tb1)), NULL, NULL) < 0)
2073                 return NULL;
2074
2075         if (tb[1] == NULL)
2076                 return NULL;
2077         if (nla_parse_nested_deprecated(tb2, TCA_ACT_MAX, tb[1], tcf_action_policy, NULL) < 0)
2078                 return NULL;
2079         kind = tb2[TCA_ACT_KIND];
2080
2081         return kind;
2082 }
2083
2084 static int tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
2085 {
2086         struct net *net = sock_net(skb->sk);
2087         struct nlmsghdr *nlh;
2088         unsigned char *b = skb_tail_pointer(skb);
2089         struct nlattr *nest;
2090         struct tc_action_ops *a_o;
2091         int ret = 0;
2092         struct tcamsg *t = (struct tcamsg *) nlmsg_data(cb->nlh);
2093         struct nlattr *tb[TCA_ROOT_MAX + 1];
2094         struct nlattr *count_attr = NULL;
2095         unsigned long jiffy_since = 0;
2096         struct nlattr *kind = NULL;
2097         struct nla_bitfield32 bf;
2098         u32 msecs_since = 0;
2099         u32 act_count = 0;
2100
2101         ret = nlmsg_parse_deprecated(cb->nlh, sizeof(struct tcamsg), tb,
2102                                      TCA_ROOT_MAX, tcaa_policy, cb->extack);
2103         if (ret < 0)
2104                 return ret;
2105
2106         kind = find_dump_kind(tb);
2107         if (kind == NULL) {
2108                 pr_info("tc_dump_action: action bad kind\n");
2109                 return 0;
2110         }
2111
2112         a_o = tc_lookup_action(kind);
2113         if (a_o == NULL)
2114                 return 0;
2115
2116         cb->args[2] = 0;
2117         if (tb[TCA_ROOT_FLAGS]) {
2118                 bf = nla_get_bitfield32(tb[TCA_ROOT_FLAGS]);
2119                 cb->args[2] = bf.value;
2120         }
2121
2122         if (tb[TCA_ROOT_TIME_DELTA]) {
2123                 msecs_since = nla_get_u32(tb[TCA_ROOT_TIME_DELTA]);
2124         }
2125
2126         nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
2127                         cb->nlh->nlmsg_type, sizeof(*t), 0);
2128         if (!nlh)
2129                 goto out_module_put;
2130
2131         if (msecs_since)
2132                 jiffy_since = jiffies - msecs_to_jiffies(msecs_since);
2133
2134         t = nlmsg_data(nlh);
2135         t->tca_family = AF_UNSPEC;
2136         t->tca__pad1 = 0;
2137         t->tca__pad2 = 0;
2138         cb->args[3] = jiffy_since;
2139         count_attr = nla_reserve(skb, TCA_ROOT_COUNT, sizeof(u32));
2140         if (!count_attr)
2141                 goto out_module_put;
2142
2143         nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
2144         if (nest == NULL)
2145                 goto out_module_put;
2146
2147         ret = __tcf_generic_walker(net, skb, cb, RTM_GETACTION, a_o, NULL);
2148         if (ret < 0)
2149                 goto out_module_put;
2150
2151         if (ret > 0) {
2152                 nla_nest_end(skb, nest);
2153                 ret = skb->len;
2154                 act_count = cb->args[1];
2155                 memcpy(nla_data(count_attr), &act_count, sizeof(u32));
2156                 cb->args[1] = 0;
2157         } else
2158                 nlmsg_trim(skb, b);
2159
2160         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
2161         if (NETLINK_CB(cb->skb).portid && ret)
2162                 nlh->nlmsg_flags |= NLM_F_MULTI;
2163         module_put(a_o->owner);
2164         return skb->len;
2165
2166 out_module_put:
2167         module_put(a_o->owner);
2168         nlmsg_trim(skb, b);
2169         return skb->len;
2170 }
2171
2172 static int __init tc_action_init(void)
2173 {
2174         rtnl_register(PF_UNSPEC, RTM_NEWACTION, tc_ctl_action, NULL, 0);
2175         rtnl_register(PF_UNSPEC, RTM_DELACTION, tc_ctl_action, NULL, 0);
2176         rtnl_register(PF_UNSPEC, RTM_GETACTION, tc_ctl_action, tc_dump_action,
2177                       0);
2178
2179         return 0;
2180 }
2181
2182 subsys_initcall(tc_action_init);