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