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->act_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 static bool tc_act_in_hw(struct tc_action *act)
 173 {
 174         return !!act->in_hw_count;
 175 }
 176
 177 /* SKIP_HW and SKIP_SW are mutually exclusive flags. */
 178 static bool tc_act_flags_valid(u32 flags)
 179 {
 180         flags &= TCA_ACT_FLAGS_SKIP_HW | TCA_ACT_FLAGS_SKIP_SW;
 181
 182         return flags ^ (TCA_ACT_FLAGS_SKIP_HW | TCA_ACT_FLAGS_SKIP_SW);
 183 }
 184
 185 static int offload_action_init(struct flow_offload_action *fl_action,
 186                                struct tc_action *act,
 187                                enum offload_act_command  cmd,
 188                                struct netlink_ext_ack *extack)
 189 {
 190         int err;
 191
 192         fl_action->extack = extack;
 193         fl_action->command = cmd;
 194         fl_action->index = act->tcfa_index;
 195
 196         if (act->ops->offload_act_setup) {
 197                 spin_lock_bh(&act->tcfa_lock);
 198                 err = act->ops->offload_act_setup(act, fl_action, NULL,
 199                                                   false, extack);
 200                 spin_unlock_bh(&act->tcfa_lock);
 201                 return err;
 202         }
 203
 204         return -EOPNOTSUPP;
 205 }
 206
 207 static int tcf_action_offload_cmd_ex(struct flow_offload_action *fl_act,
 208                                      u32 *hw_count)
 209 {
 210         int err;
 211
 212         err = flow_indr_dev_setup_offload(NULL, NULL, TC_SETUP_ACT,
 213                                           fl_act, NULL, NULL);
 214         if (err < 0)
 215                 return err;
 216
 217         if (hw_count)
 218                 *hw_count = err;
 219
 220         return 0;
 221 }
 222
 223 static int tcf_action_offload_cmd_cb_ex(struct flow_offload_action *fl_act,
 224                                         u32 *hw_count,
 225                                         flow_indr_block_bind_cb_t *cb,
 226                                         void *cb_priv)
 227 {
 228         int err;
 229
 230         err = cb(NULL, NULL, cb_priv, TC_SETUP_ACT, NULL, fl_act, NULL);
 231         if (err < 0)
 232                 return err;
 233
 234         if (hw_count)
 235                 *hw_count = 1;
 236
 237         return 0;
 238 }
 239
 240 static int tcf_action_offload_cmd(struct flow_offload_action *fl_act,
 241                                   u32 *hw_count,
 242                                   flow_indr_block_bind_cb_t *cb,
 243                                   void *cb_priv)
 244 {
 245         return cb ? tcf_action_offload_cmd_cb_ex(fl_act, hw_count,
 246                                                  cb, cb_priv) :
 247                     tcf_action_offload_cmd_ex(fl_act, hw_count);
 248 }
 249
 250 static int tcf_action_offload_add_ex(struct tc_action *action,
 251                                      struct netlink_ext_ack *extack,
 252                                      flow_indr_block_bind_cb_t *cb,
 253                                      void *cb_priv)
 254 {
 255         bool skip_sw = tc_act_skip_sw(action->tcfa_flags);
 256         struct tc_action *actions[TCA_ACT_MAX_PRIO] = {
 257                 [0] = action,
 258         };
 259         struct flow_offload_action *fl_action;
 260         u32 in_hw_count = 0;
 261         int num, err = 0;
 262
 263         if (tc_act_skip_hw(action->tcfa_flags))
 264                 return 0;
 265
 266         num = tcf_offload_act_num_actions_single(action);
 267         fl_action = offload_action_alloc(num);
 268         if (!fl_action)
 269                 return -ENOMEM;
 270
 271         err = offload_action_init(fl_action, action, FLOW_ACT_REPLACE, extack);
 272         if (err)
 273                 goto fl_err;
 274
 275         err = tc_setup_action(&fl_action->action, actions, extack);
 276         if (err) {
 277                 NL_SET_ERR_MSG_MOD(extack,
 278                                    "Failed to setup tc actions for offload");
 279                 goto fl_err;
 280         }
 281
 282         err = tcf_action_offload_cmd(fl_action, &in_hw_count, cb, cb_priv);
 283         if (!err)
 284                 cb ? offload_action_hw_count_inc(action, in_hw_count) :
 285                      offload_action_hw_count_set(action, in_hw_count);
 286
 287         if (skip_sw && !tc_act_in_hw(action))
 288                 err = -EINVAL;
 289
 290         tc_cleanup_offload_action(&fl_action->action);
 291
 292 fl_err:
 293         kfree(fl_action);
 294
 295         return err;
 296 }
 297
 298 /* offload the tc action after it is inserted */
 299 static int tcf_action_offload_add(struct tc_action *action,
 300                                   struct netlink_ext_ack *extack)
 301 {
 302         return tcf_action_offload_add_ex(action, extack, NULL, NULL);
 303 }
 304
 305 int tcf_action_update_hw_stats(struct tc_action *action)
 306 {
 307         struct flow_offload_action fl_act = {};
 308         int err;
 309
 310         if (!tc_act_in_hw(action))
 311                 return -EOPNOTSUPP;
 312
 313         err = offload_action_init(&fl_act, action, FLOW_ACT_STATS, NULL);
 314         if (err)
 315                 return err;
 316
 317         err = tcf_action_offload_cmd(&fl_act, NULL, NULL, NULL);
 318         if (!err) {
 319                 preempt_disable();
 320                 tcf_action_stats_update(action, fl_act.stats.bytes,
 321                                         fl_act.stats.pkts,
 322                                         fl_act.stats.drops,
 323                                         fl_act.stats.lastused,
 324                                         true);
 325                 preempt_enable();
 326                 action->used_hw_stats = fl_act.stats.used_hw_stats;
 327                 action->used_hw_stats_valid = true;
 328         } else {
 329                 return -EOPNOTSUPP;
 330         }
 331
 332         return 0;
 333 }
 334 EXPORT_SYMBOL(tcf_action_update_hw_stats);
 335
 336 static int tcf_action_offload_del_ex(struct tc_action *action,
 337                                      flow_indr_block_bind_cb_t *cb,
 338                                      void *cb_priv)
 339 {
 340         struct flow_offload_action fl_act = {};
 341         u32 in_hw_count = 0;
 342         int err = 0;
 343
 344         if (!tc_act_in_hw(action))
 345                 return 0;
 346
 347         err = offload_action_init(&fl_act, action, FLOW_ACT_DESTROY, NULL);
 348         if (err)
 349                 return err;
 350
 351         err = tcf_action_offload_cmd(&fl_act, &in_hw_count, cb, cb_priv);
 352         if (err < 0)
 353                 return err;
 354
 355         if (!cb && action->in_hw_count != in_hw_count)
 356                 return -EINVAL;
 357
 358         /* do not need to update hw state when deleting action */
 359         if (cb && in_hw_count)
 360                 offload_action_hw_count_dec(action, in_hw_count);
 361
 362         return 0;
 363 }
 364
 365 static int tcf_action_offload_del(struct tc_action *action)
 366 {
 367         return tcf_action_offload_del_ex(action, NULL, NULL);
 368 }
 369
 370 static void tcf_action_cleanup(struct tc_action *p)
 371 {
 372         tcf_action_offload_del(p);
 373         if (p->ops->cleanup)
 374                 p->ops->cleanup(p);
 375
 376         gen_kill_estimator(&p->tcfa_rate_est);
 377         free_tcf(p);
 378 }
 379
 380 static int __tcf_action_put(struct tc_action *p, bool bind)
 381 {
 382         struct tcf_idrinfo *idrinfo = p->idrinfo;
 383
 384         if (refcount_dec_and_mutex_lock(&p->tcfa_refcnt, &idrinfo->lock)) {
 385                 if (bind)
 386                         atomic_dec(&p->tcfa_bindcnt);
 387                 idr_remove(&idrinfo->action_idr, p->tcfa_index);
 388                 mutex_unlock(&idrinfo->lock);
 389
 390                 tcf_action_cleanup(p);
 391                 return 1;
 392         }
 393
 394         if (bind)
 395                 atomic_dec(&p->tcfa_bindcnt);
 396
 397         return 0;
 398 }
 399
 400 static int __tcf_idr_release(struct tc_action *p, bool bind, bool strict)
 401 {
 402         int ret = 0;
 403
 404         /* Release with strict==1 and bind==0 is only called through act API
 405          * interface (classifiers always bind). Only case when action with
 406          * positive reference count and zero bind count can exist is when it was
 407          * also created with act API (unbinding last classifier will destroy the
 408          * action if it was created by classifier). So only case when bind count
 409          * can be changed after initial check is when unbound action is
 410          * destroyed by act API while classifier binds to action with same id
 411          * concurrently. This result either creation of new action(same behavior
 412          * as before), or reusing existing action if concurrent process
 413          * increments reference count before action is deleted. Both scenarios
 414          * are acceptable.
 415          */
 416         if (p) {
 417                 if (!bind && strict && atomic_read(&p->tcfa_bindcnt) > 0)
 418                         return -EPERM;
 419
 420                 if (__tcf_action_put(p, bind))
 421                         ret = ACT_P_DELETED;
 422         }
 423
 424         return ret;
 425 }
 426
 427 int tcf_idr_release(struct tc_action *a, bool bind)
 428 {
 429         const struct tc_action_ops *ops = a->ops;
 430         int ret;
 431
 432         ret = __tcf_idr_release(a, bind, false);
 433         if (ret == ACT_P_DELETED)
 434                 module_put(ops->owner);
 435         return ret;
 436 }
 437 EXPORT_SYMBOL(tcf_idr_release);
 438
 439 static size_t tcf_action_shared_attrs_size(const struct tc_action *act)
 440 {
 441         struct tc_cookie *act_cookie;
 442         u32 cookie_len = 0;
 443
 444         rcu_read_lock();
 445         act_cookie = rcu_dereference(act->act_cookie);
 446
 447         if (act_cookie)
 448                 cookie_len = nla_total_size(act_cookie->len);
 449         rcu_read_unlock();
 450
 451         return  nla_total_size(0) /* action number nested */
 452                 + nla_total_size(IFNAMSIZ) /* TCA_ACT_KIND */
 453                 + cookie_len /* TCA_ACT_COOKIE */
 454                 + nla_total_size(sizeof(struct nla_bitfield32)) /* TCA_ACT_HW_STATS */
 455                 + nla_total_size(0) /* TCA_ACT_STATS nested */
 456                 + nla_total_size(sizeof(struct nla_bitfield32)) /* TCA_ACT_FLAGS */
 457                 /* TCA_STATS_BASIC */
 458                 + nla_total_size_64bit(sizeof(struct gnet_stats_basic))
 459                 /* TCA_STATS_PKT64 */
 460                 + nla_total_size_64bit(sizeof(u64))
 461                 /* TCA_STATS_QUEUE */
 462                 + nla_total_size_64bit(sizeof(struct gnet_stats_queue))
 463                 + nla_total_size(0) /* TCA_OPTIONS nested */
 464                 + nla_total_size(sizeof(struct tcf_t)); /* TCA_GACT_TM */
 465 }
 466
 467 static size_t tcf_action_full_attrs_size(size_t sz)
 468 {
 469         return NLMSG_HDRLEN                     /* struct nlmsghdr */
 470                 + sizeof(struct tcamsg)
 471                 + nla_total_size(0)             /* TCA_ACT_TAB nested */
 472                 + sz;
 473 }
 474
 475 static size_t tcf_action_fill_size(const struct tc_action *act)
 476 {
 477         size_t sz = tcf_action_shared_attrs_size(act);
 478
 479         if (act->ops->get_fill_size)
 480                 return act->ops->get_fill_size(act) + sz;
 481         return sz;
 482 }
 483
 484 static int
 485 tcf_action_dump_terse(struct sk_buff *skb, struct tc_action *a, bool from_act)
 486 {
 487         unsigned char *b = skb_tail_pointer(skb);
 488         struct tc_cookie *cookie;
 489
 490         if (nla_put_string(skb, TCA_KIND, a->ops->kind))
 491                 goto nla_put_failure;
 492         if (tcf_action_copy_stats(skb, a, 0))
 493                 goto nla_put_failure;
 494         if (from_act && nla_put_u32(skb, TCA_ACT_INDEX, a->tcfa_index))
 495                 goto nla_put_failure;
 496
 497         rcu_read_lock();
 498         cookie = rcu_dereference(a->act_cookie);
 499         if (cookie) {
 500                 if (nla_put(skb, TCA_ACT_COOKIE, cookie->len, cookie->data)) {
 501                         rcu_read_unlock();
 502                         goto nla_put_failure;
 503                 }
 504         }
 505         rcu_read_unlock();
 506
 507         return 0;
 508
 509 nla_put_failure:
 510         nlmsg_trim(skb, b);
 511         return -1;
 512 }
 513
 514 static int tcf_dump_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb,
 515                            struct netlink_callback *cb)
 516 {
 517         int err = 0, index = -1, s_i = 0, n_i = 0;
 518         u32 act_flags = cb->args[2];
 519         unsigned long jiffy_since = cb->args[3];
 520         struct nlattr *nest;
 521         struct idr *idr = &idrinfo->action_idr;
 522         struct tc_action *p;
 523         unsigned long id = 1;
 524         unsigned long tmp;
 525
 526         mutex_lock(&idrinfo->lock);
 527
 528         s_i = cb->args[0];
 529
 530         idr_for_each_entry_ul(idr, p, tmp, id) {
 531                 index++;
 532                 if (index < s_i)
 533                         continue;
 534                 if (IS_ERR(p))
 535                         continue;
 536
 537                 if (jiffy_since &&
 538                     time_after(jiffy_since,
 539                                (unsigned long)p->tcfa_tm.lastuse))
 540                         continue;
 541
 542                 nest = nla_nest_start_noflag(skb, n_i);
 543                 if (!nest) {
 544                         index--;
 545                         goto nla_put_failure;
 546                 }
 547                 err = (act_flags & TCA_ACT_FLAG_TERSE_DUMP) ?
 548                         tcf_action_dump_terse(skb, p, true) :
 549                         tcf_action_dump_1(skb, p, 0, 0);
 550                 if (err < 0) {
 551                         index--;
 552                         nlmsg_trim(skb, nest);
 553                         goto done;
 554                 }
 555                 nla_nest_end(skb, nest);
 556                 n_i++;
 557                 if (!(act_flags & TCA_ACT_FLAG_LARGE_DUMP_ON) &&
 558                     n_i >= TCA_ACT_MAX_PRIO)
 559                         goto done;
 560         }
 561 done:
 562         if (index >= 0)
 563                 cb->args[0] = index + 1;
 564
 565         mutex_unlock(&idrinfo->lock);
 566         if (n_i) {
 567                 if (act_flags & TCA_ACT_FLAG_LARGE_DUMP_ON)
 568                         cb->args[1] = n_i;
 569         }
 570         return n_i;
 571
 572 nla_put_failure:
 573         nla_nest_cancel(skb, nest);
 574         goto done;
 575 }
 576
 577 static int tcf_idr_release_unsafe(struct tc_action *p)
 578 {
 579         if (atomic_read(&p->tcfa_bindcnt) > 0)
 580                 return -EPERM;
 581
 582         if (refcount_dec_and_test(&p->tcfa_refcnt)) {
 583                 idr_remove(&p->idrinfo->action_idr, p->tcfa_index);
 584                 tcf_action_cleanup(p);
 585                 return ACT_P_DELETED;
 586         }
 587
 588         return 0;
 589 }
 590
 591 static int tcf_del_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb,
 592                           const struct tc_action_ops *ops,
 593                           struct netlink_ext_ack *extack)
 594 {
 595         struct nlattr *nest;
 596         int n_i = 0;
 597         int ret = -EINVAL;
 598         struct idr *idr = &idrinfo->action_idr;
 599         struct tc_action *p;
 600         unsigned long id = 1;
 601         unsigned long tmp;
 602
 603         nest = nla_nest_start_noflag(skb, 0);
 604         if (nest == NULL)
 605                 goto nla_put_failure;
 606         if (nla_put_string(skb, TCA_KIND, ops->kind))
 607                 goto nla_put_failure;
 608
 609         ret = 0;
 610         mutex_lock(&idrinfo->lock);
 611         idr_for_each_entry_ul(idr, p, tmp, id) {
 612                 if (IS_ERR(p))
 613                         continue;
 614                 ret = tcf_idr_release_unsafe(p);
 615                 if (ret == ACT_P_DELETED)
 616                         module_put(ops->owner);
 617                 else if (ret < 0)
 618                         break;
 619                 n_i++;
 620         }
 621         mutex_unlock(&idrinfo->lock);
 622         if (ret < 0) {
 623                 if (n_i)
 624                         NL_SET_ERR_MSG(extack, "Unable to flush all TC actions");
 625                 else
 626                         goto nla_put_failure;
 627         }
 628
 629         ret = nla_put_u32(skb, TCA_FCNT, n_i);
 630         if (ret)
 631                 goto nla_put_failure;
 632         nla_nest_end(skb, nest);
 633
 634         return n_i;
 635 nla_put_failure:
 636         nla_nest_cancel(skb, nest);
 637         return ret;
 638 }
 639
 640 int tcf_generic_walker(struct tc_action_net *tn, struct sk_buff *skb,
 641                        struct netlink_callback *cb, int type,
 642                        const struct tc_action_ops *ops,
 643                        struct netlink_ext_ack *extack)
 644 {
 645         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 646
 647         if (type == RTM_DELACTION) {
 648                 return tcf_del_walker(idrinfo, skb, ops, extack);
 649         } else if (type == RTM_GETACTION) {
 650                 return tcf_dump_walker(idrinfo, skb, cb);
 651         } else {
 652                 WARN(1, "tcf_generic_walker: unknown command %d\n", type);
 653                 NL_SET_ERR_MSG(extack, "tcf_generic_walker: unknown command");
 654                 return -EINVAL;
 655         }
 656 }
 657 EXPORT_SYMBOL(tcf_generic_walker);
 658
 659 int tcf_idr_search(struct tc_action_net *tn, struct tc_action **a, u32 index)
 660 {
 661         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 662         struct tc_action *p;
 663
 664         mutex_lock(&idrinfo->lock);
 665         p = idr_find(&idrinfo->action_idr, index);
 666         if (IS_ERR(p))
 667                 p = NULL;
 668         else if (p)
 669                 refcount_inc(&p->tcfa_refcnt);
 670         mutex_unlock(&idrinfo->lock);
 671
 672         if (p) {
 673                 *a = p;
 674                 return true;
 675         }
 676         return false;
 677 }
 678 EXPORT_SYMBOL(tcf_idr_search);
 679
 680 static int __tcf_generic_walker(struct net *net, struct sk_buff *skb,
 681                                 struct netlink_callback *cb, int type,
 682                                 const struct tc_action_ops *ops,
 683                                 struct netlink_ext_ack *extack)
 684 {
 685         struct tc_action_net *tn = net_generic(net, ops->net_id);
 686
 687         if (unlikely(ops->walk))
 688                 return ops->walk(net, skb, cb, type, ops, extack);
 689
 690         return tcf_generic_walker(tn, skb, cb, type, ops, extack);
 691 }
 692
 693 static int __tcf_idr_search(struct net *net,
 694                             const struct tc_action_ops *ops,
 695                             struct tc_action **a, u32 index)
 696 {
 697         struct tc_action_net *tn = net_generic(net, ops->net_id);
 698
 699         if (unlikely(ops->lookup))
 700                 return ops->lookup(net, a, index);
 701
 702         return tcf_idr_search(tn, a, index);
 703 }
 704
 705 static int tcf_idr_delete_index(struct tcf_idrinfo *idrinfo, u32 index)
 706 {
 707         struct tc_action *p;
 708         int ret = 0;
 709
 710         mutex_lock(&idrinfo->lock);
 711         p = idr_find(&idrinfo->action_idr, index);
 712         if (!p) {
 713                 mutex_unlock(&idrinfo->lock);
 714                 return -ENOENT;
 715         }
 716
 717         if (!atomic_read(&p->tcfa_bindcnt)) {
 718                 if (refcount_dec_and_test(&p->tcfa_refcnt)) {
 719                         struct module *owner = p->ops->owner;
 720
 721                         WARN_ON(p != idr_remove(&idrinfo->action_idr,
 722                                                 p->tcfa_index));
 723                         mutex_unlock(&idrinfo->lock);
 724
 725                         tcf_action_cleanup(p);
 726                         module_put(owner);
 727                         return 0;
 728                 }
 729                 ret = 0;
 730         } else {
 731                 ret = -EPERM;
 732         }
 733
 734         mutex_unlock(&idrinfo->lock);
 735         return ret;
 736 }
 737
 738 int tcf_idr_create(struct tc_action_net *tn, u32 index, struct nlattr *est,
 739                    struct tc_action **a, const struct tc_action_ops *ops,
 740                    int bind, bool cpustats, u32 flags)
 741 {
 742         struct tc_action *p = kzalloc(ops->size, GFP_KERNEL);
 743         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 744         int err = -ENOMEM;
 745
 746         if (unlikely(!p))
 747                 return -ENOMEM;
 748         refcount_set(&p->tcfa_refcnt, 1);
 749         if (bind)
 750                 atomic_set(&p->tcfa_bindcnt, 1);
 751
 752         if (cpustats) {
 753                 p->cpu_bstats = netdev_alloc_pcpu_stats(struct gnet_stats_basic_sync);
 754                 if (!p->cpu_bstats)
 755                         goto err1;
 756                 p->cpu_bstats_hw = netdev_alloc_pcpu_stats(struct gnet_stats_basic_sync);
 757                 if (!p->cpu_bstats_hw)
 758                         goto err2;
 759                 p->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
 760                 if (!p->cpu_qstats)
 761                         goto err3;
 762         }
 763         gnet_stats_basic_sync_init(&p->tcfa_bstats);
 764         gnet_stats_basic_sync_init(&p->tcfa_bstats_hw);
 765         spin_lock_init(&p->tcfa_lock);
 766         p->tcfa_index = index;
 767         p->tcfa_tm.install = jiffies;
 768         p->tcfa_tm.lastuse = jiffies;
 769         p->tcfa_tm.firstuse = 0;
 770         p->tcfa_flags = flags;
 771         if (est) {
 772                 err = gen_new_estimator(&p->tcfa_bstats, p->cpu_bstats,
 773                                         &p->tcfa_rate_est,
 774                                         &p->tcfa_lock, false, est);
 775                 if (err)
 776                         goto err4;
 777         }
 778
 779         p->idrinfo = idrinfo;
 780         __module_get(ops->owner);
 781         p->ops = ops;
 782         *a = p;
 783         return 0;
 784 err4:
 785         free_percpu(p->cpu_qstats);
 786 err3:
 787         free_percpu(p->cpu_bstats_hw);
 788 err2:
 789         free_percpu(p->cpu_bstats);
 790 err1:
 791         kfree(p);
 792         return err;
 793 }
 794 EXPORT_SYMBOL(tcf_idr_create);
 795
 796 int tcf_idr_create_from_flags(struct tc_action_net *tn, u32 index,
 797                               struct nlattr *est, struct tc_action **a,
 798                               const struct tc_action_ops *ops, int bind,
 799                               u32 flags)
 800 {
 801         /* Set cpustats according to actions flags. */
 802         return tcf_idr_create(tn, index, est, a, ops, bind,
 803                               !(flags & TCA_ACT_FLAGS_NO_PERCPU_STATS), flags);
 804 }
 805 EXPORT_SYMBOL(tcf_idr_create_from_flags);
 806
 807 /* Cleanup idr index that was allocated but not initialized. */
 808
 809 void tcf_idr_cleanup(struct tc_action_net *tn, u32 index)
 810 {
 811         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 812
 813         mutex_lock(&idrinfo->lock);
 814         /* Remove ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */
 815         WARN_ON(!IS_ERR(idr_remove(&idrinfo->action_idr, index)));
 816         mutex_unlock(&idrinfo->lock);
 817 }
 818 EXPORT_SYMBOL(tcf_idr_cleanup);
 819
 820 /* Check if action with specified index exists. If actions is found, increments
 821  * its reference and bind counters, and return 1. Otherwise insert temporary
 822  * error pointer (to prevent concurrent users from inserting actions with same
 823  * index) and return 0.
 824  */
 825
 826 int tcf_idr_check_alloc(struct tc_action_net *tn, u32 *index,
 827                         struct tc_action **a, int bind)
 828 {
 829         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 830         struct tc_action *p;
 831         int ret;
 832
 833 again:
 834         mutex_lock(&idrinfo->lock);
 835         if (*index) {
 836                 p = idr_find(&idrinfo->action_idr, *index);
 837                 if (IS_ERR(p)) {
 838                         /* This means that another process allocated
 839                          * index but did not assign the pointer yet.
 840                          */
 841                         mutex_unlock(&idrinfo->lock);
 842                         goto again;
 843                 }
 844
 845                 if (p) {
 846                         refcount_inc(&p->tcfa_refcnt);
 847                         if (bind)
 848                                 atomic_inc(&p->tcfa_bindcnt);
 849                         *a = p;
 850                         ret = 1;
 851                 } else {
 852                         *a = NULL;
 853                         ret = idr_alloc_u32(&idrinfo->action_idr, NULL, index,
 854                                             *index, GFP_KERNEL);
 855                         if (!ret)
 856                                 idr_replace(&idrinfo->action_idr,
 857                                             ERR_PTR(-EBUSY), *index);
 858                 }
 859         } else {
 860                 *index = 1;
 861                 *a = NULL;
 862                 ret = idr_alloc_u32(&idrinfo->action_idr, NULL, index,
 863                                     UINT_MAX, GFP_KERNEL);
 864                 if (!ret)
 865                         idr_replace(&idrinfo->action_idr, ERR_PTR(-EBUSY),
 866                                     *index);
 867         }
 868         mutex_unlock(&idrinfo->lock);
 869         return ret;
 870 }
 871 EXPORT_SYMBOL(tcf_idr_check_alloc);
 872
 873 void tcf_idrinfo_destroy(const struct tc_action_ops *ops,
 874                          struct tcf_idrinfo *idrinfo)
 875 {
 876         struct idr *idr = &idrinfo->action_idr;
 877         struct tc_action *p;
 878         int ret;
 879         unsigned long id = 1;
 880         unsigned long tmp;
 881
 882         idr_for_each_entry_ul(idr, p, tmp, id) {
 883                 ret = __tcf_idr_release(p, false, true);
 884                 if (ret == ACT_P_DELETED)
 885                         module_put(ops->owner);
 886                 else if (ret < 0)
 887                         return;
 888         }
 889         idr_destroy(&idrinfo->action_idr);
 890 }
 891 EXPORT_SYMBOL(tcf_idrinfo_destroy);
 892
 893 static LIST_HEAD(act_base);
 894 static DEFINE_RWLOCK(act_mod_lock);
 895 /* since act ops id is stored in pernet subsystem list,
 896  * then there is no way to walk through only all the action
 897  * subsystem, so we keep tc action pernet ops id for
 898  * reoffload to walk through.
 899  */
 900 static LIST_HEAD(act_pernet_id_list);
 901 static DEFINE_MUTEX(act_id_mutex);
 902 struct tc_act_pernet_id {
 903         struct list_head list;
 904         unsigned int id;
 905 };
 906
 907 static int tcf_pernet_add_id_list(unsigned int id)
 908 {
 909         struct tc_act_pernet_id *id_ptr;
 910         int ret = 0;
 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                         ret = -EEXIST;
 916                         goto err_out;
 917                 }
 918         }
 919
 920         id_ptr = kzalloc(sizeof(*id_ptr), GFP_KERNEL);
 921         if (!id_ptr) {
 922                 ret = -ENOMEM;
 923                 goto err_out;
 924         }
 925         id_ptr->id = id;
 926
 927         list_add_tail(&id_ptr->list, &act_pernet_id_list);
 928
 929 err_out:
 930         mutex_unlock(&act_id_mutex);
 931         return ret;
 932 }
 933
 934 static void tcf_pernet_del_id_list(unsigned int id)
 935 {
 936         struct tc_act_pernet_id *id_ptr;
 937
 938         mutex_lock(&act_id_mutex);
 939         list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
 940                 if (id_ptr->id == id) {
 941                         list_del(&id_ptr->list);
 942                         kfree(id_ptr);
 943                         break;
 944                 }
 945         }
 946         mutex_unlock(&act_id_mutex);
 947 }
 948
 949 int tcf_register_action(struct tc_action_ops *act,
 950                         struct pernet_operations *ops)
 951 {
 952         struct tc_action_ops *a;
 953         int ret;
 954
 955         if (!act->act || !act->dump || !act->init)
 956                 return -EINVAL;
 957
 958         /* We have to register pernet ops before making the action ops visible,
 959          * otherwise tcf_action_init_1() could get a partially initialized
 960          * netns.
 961          */
 962         ret = register_pernet_subsys(ops);
 963         if (ret)
 964                 return ret;
 965
 966         if (ops->id) {
 967                 ret = tcf_pernet_add_id_list(*ops->id);
 968                 if (ret)
 969                         goto err_id;
 970         }
 971
 972         write_lock(&act_mod_lock);
 973         list_for_each_entry(a, &act_base, head) {
 974                 if (act->id == a->id || (strcmp(act->kind, a->kind) == 0)) {
 975                         ret = -EEXIST;
 976                         goto err_out;
 977                 }
 978         }
 979         list_add_tail(&act->head, &act_base);
 980         write_unlock(&act_mod_lock);
 981
 982         return 0;
 983
 984 err_out:
 985         write_unlock(&act_mod_lock);
 986         if (ops->id)
 987                 tcf_pernet_del_id_list(*ops->id);
 988 err_id:
 989         unregister_pernet_subsys(ops);
 990         return ret;
 991 }
 992 EXPORT_SYMBOL(tcf_register_action);
 993
 994 int tcf_unregister_action(struct tc_action_ops *act,
 995                           struct pernet_operations *ops)
 996 {
 997         struct tc_action_ops *a;
 998         int err = -ENOENT;
 999
1000         write_lock(&act_mod_lock);
1001         list_for_each_entry(a, &act_base, head) {
1002                 if (a == act) {
1003                         list_del(&act->head);
1004                         err = 0;
1005                         break;
1006                 }
1007         }
1008         write_unlock(&act_mod_lock);
1009         if (!err) {
1010                 unregister_pernet_subsys(ops);
1011                 if (ops->id)
1012                         tcf_pernet_del_id_list(*ops->id);
1013         }
1014         return err;
1015 }
1016 EXPORT_SYMBOL(tcf_unregister_action);
1017
1018 /* lookup by name */
1019 static struct tc_action_ops *tc_lookup_action_n(char *kind)
1020 {
1021         struct tc_action_ops *a, *res = NULL;
1022
1023         if (kind) {
1024                 read_lock(&act_mod_lock);
1025                 list_for_each_entry(a, &act_base, head) {
1026                         if (strcmp(kind, a->kind) == 0) {
1027                                 if (try_module_get(a->owner))
1028                                         res = a;
1029                                 break;
1030                         }
1031                 }
1032                 read_unlock(&act_mod_lock);
1033         }
1034         return res;
1035 }
1036
1037 /* lookup by nlattr */
1038 static struct tc_action_ops *tc_lookup_action(struct nlattr *kind)
1039 {
1040         struct tc_action_ops *a, *res = NULL;
1041
1042         if (kind) {
1043                 read_lock(&act_mod_lock);
1044                 list_for_each_entry(a, &act_base, head) {
1045                         if (nla_strcmp(kind, a->kind) == 0) {
1046                                 if (try_module_get(a->owner))
1047                                         res = a;
1048                                 break;
1049                         }
1050                 }
1051                 read_unlock(&act_mod_lock);
1052         }
1053         return res;
1054 }
1055
1056 /*TCA_ACT_MAX_PRIO is 32, there count up to 32 */
1057 #define TCA_ACT_MAX_PRIO_MASK 0x1FF
1058 int tcf_action_exec(struct sk_buff *skb, struct tc_action **actions,
1059                     int nr_actions, struct tcf_result *res)
1060 {
1061         u32 jmp_prgcnt = 0;
1062         u32 jmp_ttl = TCA_ACT_MAX_PRIO; /*matches actions per filter */
1063         int i;
1064         int ret = TC_ACT_OK;
1065
1066         if (skb_skip_tc_classify(skb))
1067                 return TC_ACT_OK;
1068
1069 restart_act_graph:
1070         for (i = 0; i < nr_actions; i++) {
1071                 const struct tc_action *a = actions[i];
1072                 int repeat_ttl;
1073
1074                 if (jmp_prgcnt > 0) {
1075                         jmp_prgcnt -= 1;
1076                         continue;
1077                 }
1078
1079                 if (tc_act_skip_sw(a->tcfa_flags))
1080                         continue;
1081
1082                 repeat_ttl = 32;
1083 repeat:
1084                 ret = tc_act(skb, a, res);
1085                 if (unlikely(ret == TC_ACT_REPEAT)) {
1086                         if (--repeat_ttl != 0)
1087                                 goto repeat;
1088                         /* suspicious opcode, stop pipeline */
1089                         net_warn_ratelimited("TC_ACT_REPEAT abuse ?\n");
1090                         return TC_ACT_OK;
1091                 }
1092                 if (TC_ACT_EXT_CMP(ret, TC_ACT_JUMP)) {
1093                         jmp_prgcnt = ret & TCA_ACT_MAX_PRIO_MASK;
1094                         if (!jmp_prgcnt || (jmp_prgcnt > nr_actions)) {
1095                                 /* faulty opcode, stop pipeline */
1096                                 return TC_ACT_OK;
1097                         } else {
1098                                 jmp_ttl -= 1;
1099                                 if (jmp_ttl > 0)
1100                                         goto restart_act_graph;
1101                                 else /* faulty graph, stop pipeline */
1102                                         return TC_ACT_OK;
1103                         }
1104                 } else if (TC_ACT_EXT_CMP(ret, TC_ACT_GOTO_CHAIN)) {
1105                         if (unlikely(!rcu_access_pointer(a->goto_chain))) {
1106                                 net_warn_ratelimited("can't go to NULL chain!\n");
1107                                 return TC_ACT_SHOT;
1108                         }
1109                         tcf_action_goto_chain_exec(a, res);
1110                 }
1111
1112                 if (ret != TC_ACT_PIPE)
1113                         break;
1114         }
1115
1116         return ret;
1117 }
1118 EXPORT_SYMBOL(tcf_action_exec);
1119
1120 int tcf_action_destroy(struct tc_action *actions[], int bind)
1121 {
1122         const struct tc_action_ops *ops;
1123         struct tc_action *a;
1124         int ret = 0, i;
1125
1126         for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
1127                 a = actions[i];
1128                 actions[i] = NULL;
1129                 ops = a->ops;
1130                 ret = __tcf_idr_release(a, bind, true);
1131                 if (ret == ACT_P_DELETED)
1132                         module_put(ops->owner);
1133                 else if (ret < 0)
1134                         return ret;
1135         }
1136         return ret;
1137 }
1138
1139 static int tcf_action_put(struct tc_action *p)
1140 {
1141         return __tcf_action_put(p, false);
1142 }
1143
1144 /* Put all actions in this array, skip those NULL's. */
1145 static void tcf_action_put_many(struct tc_action *actions[])
1146 {
1147         int i;
1148
1149         for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
1150                 struct tc_action *a = actions[i];
1151                 const struct tc_action_ops *ops;
1152
1153                 if (!a)
1154                         continue;
1155                 ops = a->ops;
1156                 if (tcf_action_put(a))
1157                         module_put(ops->owner);
1158         }
1159 }
1160
1161 int
1162 tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
1163 {
1164         return a->ops->dump(skb, a, bind, ref);
1165 }
1166
1167 int
1168 tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
1169 {
1170         int err = -EINVAL;
1171         unsigned char *b = skb_tail_pointer(skb);
1172         struct nlattr *nest;
1173         u32 flags;
1174
1175         if (tcf_action_dump_terse(skb, a, false))
1176                 goto nla_put_failure;
1177
1178         if (a->hw_stats != TCA_ACT_HW_STATS_ANY &&
1179             nla_put_bitfield32(skb, TCA_ACT_HW_STATS,
1180                                a->hw_stats, TCA_ACT_HW_STATS_ANY))
1181                 goto nla_put_failure;
1182
1183         if (a->used_hw_stats_valid &&
1184             nla_put_bitfield32(skb, TCA_ACT_USED_HW_STATS,
1185                                a->used_hw_stats, TCA_ACT_HW_STATS_ANY))
1186                 goto nla_put_failure;
1187
1188         flags = a->tcfa_flags & TCA_ACT_FLAGS_USER_MASK;
1189         if (flags &&
1190             nla_put_bitfield32(skb, TCA_ACT_FLAGS,
1191                                flags, flags))
1192                 goto nla_put_failure;
1193
1194         if (nla_put_u32(skb, TCA_ACT_IN_HW_COUNT, a->in_hw_count))
1195                 goto nla_put_failure;
1196
1197         nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
1198         if (nest == NULL)
1199                 goto nla_put_failure;
1200         err = tcf_action_dump_old(skb, a, bind, ref);
1201         if (err > 0) {
1202                 nla_nest_end(skb, nest);
1203                 return err;
1204         }
1205
1206 nla_put_failure:
1207         nlmsg_trim(skb, b);
1208         return -1;
1209 }
1210 EXPORT_SYMBOL(tcf_action_dump_1);
1211
1212 int tcf_action_dump(struct sk_buff *skb, struct tc_action *actions[],
1213                     int bind, int ref, bool terse)
1214 {
1215         struct tc_action *a;
1216         int err = -EINVAL, i;
1217         struct nlattr *nest;
1218
1219         for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
1220                 a = actions[i];
1221                 nest = nla_nest_start_noflag(skb, i + 1);
1222                 if (nest == NULL)
1223                         goto nla_put_failure;
1224                 err = terse ? tcf_action_dump_terse(skb, a, false) :
1225                         tcf_action_dump_1(skb, a, bind, ref);
1226                 if (err < 0)
1227                         goto errout;
1228                 nla_nest_end(skb, nest);
1229         }
1230
1231         return 0;
1232
1233 nla_put_failure:
1234         err = -EINVAL;
1235 errout:
1236         nla_nest_cancel(skb, nest);
1237         return err;
1238 }
1239
1240 static struct tc_cookie *nla_memdup_cookie(struct nlattr **tb)
1241 {
1242         struct tc_cookie *c = kzalloc(sizeof(*c), GFP_KERNEL);
1243         if (!c)
1244                 return NULL;
1245
1246         c->data = nla_memdup(tb[TCA_ACT_COOKIE], GFP_KERNEL);
1247         if (!c->data) {
1248                 kfree(c);
1249                 return NULL;
1250         }
1251         c->len = nla_len(tb[TCA_ACT_COOKIE]);
1252
1253         return c;
1254 }
1255
1256 static u8 tcf_action_hw_stats_get(struct nlattr *hw_stats_attr)
1257 {
1258         struct nla_bitfield32 hw_stats_bf;
1259
1260         /* If the user did not pass the attr, that means he does
1261          * not care about the type. Return "any" in that case
1262          * which is setting on all supported types.
1263          */
1264         if (!hw_stats_attr)
1265                 return TCA_ACT_HW_STATS_ANY;
1266         hw_stats_bf = nla_get_bitfield32(hw_stats_attr);
1267         return hw_stats_bf.value;
1268 }
1269
1270 static const struct nla_policy tcf_action_policy[TCA_ACT_MAX + 1] = {
1271         [TCA_ACT_KIND]          = { .type = NLA_STRING },
1272         [TCA_ACT_INDEX]         = { .type = NLA_U32 },
1273         [TCA_ACT_COOKIE]        = { .type = NLA_BINARY,
1274                                     .len = TC_COOKIE_MAX_SIZE },
1275         [TCA_ACT_OPTIONS]       = { .type = NLA_NESTED },
1276         [TCA_ACT_FLAGS]         = NLA_POLICY_BITFIELD32(TCA_ACT_FLAGS_NO_PERCPU_STATS |
1277                                                         TCA_ACT_FLAGS_SKIP_HW |
1278                                                         TCA_ACT_FLAGS_SKIP_SW),
1279         [TCA_ACT_HW_STATS]      = NLA_POLICY_BITFIELD32(TCA_ACT_HW_STATS_ANY),
1280 };
1281
1282 void tcf_idr_insert_many(struct tc_action *actions[])
1283 {
1284         int i;
1285
1286         for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
1287                 struct tc_action *a = actions[i];
1288                 struct tcf_idrinfo *idrinfo;
1289
1290                 if (!a)
1291                         continue;
1292                 idrinfo = a->idrinfo;
1293                 mutex_lock(&idrinfo->lock);
1294                 /* Replace ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc if
1295                  * it is just created, otherwise this is just a nop.
1296                  */
1297                 idr_replace(&idrinfo->action_idr, a, a->tcfa_index);
1298                 mutex_unlock(&idrinfo->lock);
1299         }
1300 }
1301
1302 struct tc_action_ops *tc_action_load_ops(struct nlattr *nla, bool police,
1303                                          bool rtnl_held,
1304                                          struct netlink_ext_ack *extack)
1305 {
1306         struct nlattr *tb[TCA_ACT_MAX + 1];
1307         struct tc_action_ops *a_o;
1308         char act_name[IFNAMSIZ];
1309         struct nlattr *kind;
1310         int err;
1311
1312         if (!police) {
1313                 err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1314                                                   tcf_action_policy, extack);
1315                 if (err < 0)
1316                         return ERR_PTR(err);
1317                 err = -EINVAL;
1318                 kind = tb[TCA_ACT_KIND];
1319                 if (!kind) {
1320                         NL_SET_ERR_MSG(extack, "TC action kind must be specified");
1321                         return ERR_PTR(err);
1322                 }
1323                 if (nla_strscpy(act_name, kind, IFNAMSIZ) < 0) {
1324                         NL_SET_ERR_MSG(extack, "TC action name too long");
1325                         return ERR_PTR(err);
1326                 }
1327         } else {
1328                 if (strlcpy(act_name, "police", IFNAMSIZ) >= IFNAMSIZ) {
1329                         NL_SET_ERR_MSG(extack, "TC action name too long");
1330                         return ERR_PTR(-EINVAL);
1331                 }
1332         }
1333
1334         a_o = tc_lookup_action_n(act_name);
1335         if (a_o == NULL) {
1336 #ifdef CONFIG_MODULES
1337                 if (rtnl_held)
1338                         rtnl_unlock();
1339                 request_module("act_%s", act_name);
1340                 if (rtnl_held)
1341                         rtnl_lock();
1342
1343                 a_o = tc_lookup_action_n(act_name);
1344
1345                 /* We dropped the RTNL semaphore in order to
1346                  * perform the module load.  So, even if we
1347                  * succeeded in loading the module we have to
1348                  * tell the caller to replay the request.  We
1349                  * indicate this using -EAGAIN.
1350                  */
1351                 if (a_o != NULL) {
1352                         module_put(a_o->owner);
1353                         return ERR_PTR(-EAGAIN);
1354                 }
1355 #endif
1356                 NL_SET_ERR_MSG(extack, "Failed to load TC action module");
1357                 return ERR_PTR(-ENOENT);
1358         }
1359
1360         return a_o;
1361 }
1362
1363 struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
1364                                     struct nlattr *nla, struct nlattr *est,
1365                                     struct tc_action_ops *a_o, int *init_res,
1366                                     u32 flags, struct netlink_ext_ack *extack)
1367 {
1368         bool police = flags & TCA_ACT_FLAGS_POLICE;
1369         struct nla_bitfield32 userflags = { 0, 0 };
1370         u8 hw_stats = TCA_ACT_HW_STATS_ANY;
1371         struct nlattr *tb[TCA_ACT_MAX + 1];
1372         struct tc_cookie *cookie = NULL;
1373         struct tc_action *a;
1374         int err;
1375
1376         /* backward compatibility for policer */
1377         if (!police) {
1378                 err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1379                                                   tcf_action_policy, extack);
1380                 if (err < 0)
1381                         return ERR_PTR(err);
1382                 if (tb[TCA_ACT_COOKIE]) {
1383                         cookie = nla_memdup_cookie(tb);
1384                         if (!cookie) {
1385                                 NL_SET_ERR_MSG(extack, "No memory to generate TC cookie");
1386                                 err = -ENOMEM;
1387                                 goto err_out;
1388                         }
1389                 }
1390                 hw_stats = tcf_action_hw_stats_get(tb[TCA_ACT_HW_STATS]);
1391                 if (tb[TCA_ACT_FLAGS]) {
1392                         userflags = nla_get_bitfield32(tb[TCA_ACT_FLAGS]);
1393                         if (!tc_act_flags_valid(userflags.value)) {
1394                                 err = -EINVAL;
1395                                 goto err_out;
1396                         }
1397                 }
1398
1399                 err = a_o->init(net, tb[TCA_ACT_OPTIONS], est, &a, tp,
1400                                 userflags.value | flags, extack);
1401         } else {
1402                 err = a_o->init(net, nla, est, &a, tp, userflags.value | flags,
1403                                 extack);
1404         }
1405         if (err < 0)
1406                 goto err_out;
1407         *init_res = err;
1408
1409         if (!police && tb[TCA_ACT_COOKIE])
1410                 tcf_set_action_cookie(&a->act_cookie, cookie);
1411
1412         if (!police)
1413                 a->hw_stats = hw_stats;
1414
1415         return a;
1416
1417 err_out:
1418         if (cookie) {
1419                 kfree(cookie->data);
1420                 kfree(cookie);
1421         }
1422         return ERR_PTR(err);
1423 }
1424
1425 static bool tc_act_bind(u32 flags)
1426 {
1427         return !!(flags & TCA_ACT_FLAGS_BIND);
1428 }
1429
1430 /* Returns numbers of initialized actions or negative error. */
1431
1432 int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla,
1433                     struct nlattr *est, struct tc_action *actions[],
1434                     int init_res[], size_t *attr_size,
1435                     u32 flags, u32 fl_flags,
1436                     struct netlink_ext_ack *extack)
1437 {
1438         struct tc_action_ops *ops[TCA_ACT_MAX_PRIO] = {};
1439         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1440         struct tc_action *act;
1441         size_t sz = 0;
1442         int err;
1443         int i;
1444
1445         err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX_PRIO, nla, NULL,
1446                                           extack);
1447         if (err < 0)
1448                 return err;
1449
1450         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1451                 struct tc_action_ops *a_o;
1452
1453                 a_o = tc_action_load_ops(tb[i], flags & TCA_ACT_FLAGS_POLICE,
1454                                          !(flags & TCA_ACT_FLAGS_NO_RTNL),
1455                                          extack);
1456                 if (IS_ERR(a_o)) {
1457                         err = PTR_ERR(a_o);
1458                         goto err_mod;
1459                 }
1460                 ops[i - 1] = a_o;
1461         }
1462
1463         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1464                 act = tcf_action_init_1(net, tp, tb[i], est, ops[i - 1],
1465                                         &init_res[i - 1], flags, extack);
1466                 if (IS_ERR(act)) {
1467                         err = PTR_ERR(act);
1468                         goto err;
1469                 }
1470                 sz += tcf_action_fill_size(act);
1471                 /* Start from index 0 */
1472                 actions[i - 1] = act;
1473                 if (tc_act_bind(flags)) {
1474                         bool skip_sw = tc_skip_sw(fl_flags);
1475                         bool skip_hw = tc_skip_hw(fl_flags);
1476
1477                         if (tc_act_bind(act->tcfa_flags))
1478                                 continue;
1479                         if (skip_sw != tc_act_skip_sw(act->tcfa_flags) ||
1480                             skip_hw != tc_act_skip_hw(act->tcfa_flags)) {
1481                                 NL_SET_ERR_MSG(extack,
1482                                                "Mismatch between action and filter offload flags");
1483                                 err = -EINVAL;
1484                                 goto err;
1485                         }
1486                 } else {
1487                         err = tcf_action_offload_add(act, extack);
1488                         if (tc_act_skip_sw(act->tcfa_flags) && err)
1489                                 goto err;
1490                 }
1491         }
1492
1493         /* We have to commit them all together, because if any error happened in
1494          * between, we could not handle the failure gracefully.
1495          */
1496         tcf_idr_insert_many(actions);
1497
1498         *attr_size = tcf_action_full_attrs_size(sz);
1499         err = i - 1;
1500         goto err_mod;
1501
1502 err:
1503         tcf_action_destroy(actions, flags & TCA_ACT_FLAGS_BIND);
1504 err_mod:
1505         for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
1506                 if (ops[i])
1507                         module_put(ops[i]->owner);
1508         }
1509         return err;
1510 }
1511
1512 void tcf_action_update_stats(struct tc_action *a, u64 bytes, u64 packets,
1513                              u64 drops, bool hw)
1514 {
1515         if (a->cpu_bstats) {
1516                 _bstats_update(this_cpu_ptr(a->cpu_bstats), bytes, packets);
1517
1518                 this_cpu_ptr(a->cpu_qstats)->drops += drops;
1519
1520                 if (hw)
1521                         _bstats_update(this_cpu_ptr(a->cpu_bstats_hw),
1522                                        bytes, packets);
1523                 return;
1524         }
1525
1526         _bstats_update(&a->tcfa_bstats, bytes, packets);
1527         a->tcfa_qstats.drops += drops;
1528         if (hw)
1529                 _bstats_update(&a->tcfa_bstats_hw, bytes, packets);
1530 }
1531 EXPORT_SYMBOL(tcf_action_update_stats);
1532
1533 int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *p,
1534                           int compat_mode)
1535 {
1536         int err = 0;
1537         struct gnet_dump d;
1538
1539         if (p == NULL)
1540                 goto errout;
1541
1542         /* update hw stats for this action */
1543         tcf_action_update_hw_stats(p);
1544
1545         /* compat_mode being true specifies a call that is supposed
1546          * to add additional backward compatibility statistic TLVs.
1547          */
1548         if (compat_mode) {
1549                 if (p->type == TCA_OLD_COMPAT)
1550                         err = gnet_stats_start_copy_compat(skb, 0,
1551                                                            TCA_STATS,
1552                                                            TCA_XSTATS,
1553                                                            &p->tcfa_lock, &d,
1554                                                            TCA_PAD);
1555                 else
1556                         return 0;
1557         } else
1558                 err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
1559                                             &p->tcfa_lock, &d, TCA_ACT_PAD);
1560
1561         if (err < 0)
1562                 goto errout;
1563
1564         if (gnet_stats_copy_basic(&d, p->cpu_bstats,
1565                                   &p->tcfa_bstats, false) < 0 ||
1566             gnet_stats_copy_basic_hw(&d, p->cpu_bstats_hw,
1567                                      &p->tcfa_bstats_hw, false) < 0 ||
1568             gnet_stats_copy_rate_est(&d, &p->tcfa_rate_est) < 0 ||
1569             gnet_stats_copy_queue(&d, p->cpu_qstats,
1570                                   &p->tcfa_qstats,
1571                                   p->tcfa_qstats.qlen) < 0)
1572                 goto errout;
1573
1574         if (gnet_stats_finish_copy(&d) < 0)
1575                 goto errout;
1576
1577         return 0;
1578
1579 errout:
1580         return -1;
1581 }
1582
1583 static int tca_get_fill(struct sk_buff *skb, struct tc_action *actions[],
1584                         u32 portid, u32 seq, u16 flags, int event, int bind,
1585                         int ref)
1586 {
1587         struct tcamsg *t;
1588         struct nlmsghdr *nlh;
1589         unsigned char *b = skb_tail_pointer(skb);
1590         struct nlattr *nest;
1591
1592         nlh = nlmsg_put(skb, portid, seq, event, sizeof(*t), flags);
1593         if (!nlh)
1594                 goto out_nlmsg_trim;
1595         t = nlmsg_data(nlh);
1596         t->tca_family = AF_UNSPEC;
1597         t->tca__pad1 = 0;
1598         t->tca__pad2 = 0;
1599
1600         nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
1601         if (!nest)
1602                 goto out_nlmsg_trim;
1603
1604         if (tcf_action_dump(skb, actions, bind, ref, false) < 0)
1605                 goto out_nlmsg_trim;
1606
1607         nla_nest_end(skb, nest);
1608
1609         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1610         return skb->len;
1611
1612 out_nlmsg_trim:
1613         nlmsg_trim(skb, b);
1614         return -1;
1615 }
1616
1617 static int
1618 tcf_get_notify(struct net *net, u32 portid, struct nlmsghdr *n,
1619                struct tc_action *actions[], int event,
1620                struct netlink_ext_ack *extack)
1621 {
1622         struct sk_buff *skb;
1623
1624         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1625         if (!skb)
1626                 return -ENOBUFS;
1627         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, event,
1628                          0, 1) <= 0) {
1629                 NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1630                 kfree_skb(skb);
1631                 return -EINVAL;
1632         }
1633
1634         return rtnl_unicast(skb, net, portid);
1635 }
1636
1637 static struct tc_action *tcf_action_get_1(struct net *net, struct nlattr *nla,
1638                                           struct nlmsghdr *n, u32 portid,
1639                                           struct netlink_ext_ack *extack)
1640 {
1641         struct nlattr *tb[TCA_ACT_MAX + 1];
1642         const struct tc_action_ops *ops;
1643         struct tc_action *a;
1644         int index;
1645         int err;
1646
1647         err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1648                                           tcf_action_policy, extack);
1649         if (err < 0)
1650                 goto err_out;
1651
1652         err = -EINVAL;
1653         if (tb[TCA_ACT_INDEX] == NULL ||
1654             nla_len(tb[TCA_ACT_INDEX]) < sizeof(index)) {
1655                 NL_SET_ERR_MSG(extack, "Invalid TC action index value");
1656                 goto err_out;
1657         }
1658         index = nla_get_u32(tb[TCA_ACT_INDEX]);
1659
1660         err = -EINVAL;
1661         ops = tc_lookup_action(tb[TCA_ACT_KIND]);
1662         if (!ops) { /* could happen in batch of actions */
1663                 NL_SET_ERR_MSG(extack, "Specified TC action kind not found");
1664                 goto err_out;
1665         }
1666         err = -ENOENT;
1667         if (__tcf_idr_search(net, ops, &a, index) == 0) {
1668                 NL_SET_ERR_MSG(extack, "TC action with specified index not found");
1669                 goto err_mod;
1670         }
1671
1672         module_put(ops->owner);
1673         return a;
1674
1675 err_mod:
1676         module_put(ops->owner);
1677 err_out:
1678         return ERR_PTR(err);
1679 }
1680
1681 static int tca_action_flush(struct net *net, struct nlattr *nla,
1682                             struct nlmsghdr *n, u32 portid,
1683                             struct netlink_ext_ack *extack)
1684 {
1685         struct sk_buff *skb;
1686         unsigned char *b;
1687         struct nlmsghdr *nlh;
1688         struct tcamsg *t;
1689         struct netlink_callback dcb;
1690         struct nlattr *nest;
1691         struct nlattr *tb[TCA_ACT_MAX + 1];
1692         const struct tc_action_ops *ops;
1693         struct nlattr *kind;
1694         int err = -ENOMEM;
1695
1696         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1697         if (!skb)
1698                 return err;
1699
1700         b = skb_tail_pointer(skb);
1701
1702         err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1703                                           tcf_action_policy, extack);
1704         if (err < 0)
1705                 goto err_out;
1706
1707         err = -EINVAL;
1708         kind = tb[TCA_ACT_KIND];
1709         ops = tc_lookup_action(kind);
1710         if (!ops) { /*some idjot trying to flush unknown action */
1711                 NL_SET_ERR_MSG(extack, "Cannot flush unknown TC action");
1712                 goto err_out;
1713         }
1714
1715         nlh = nlmsg_put(skb, portid, n->nlmsg_seq, RTM_DELACTION,
1716                         sizeof(*t), 0);
1717         if (!nlh) {
1718                 NL_SET_ERR_MSG(extack, "Failed to create TC action flush notification");
1719                 goto out_module_put;
1720         }
1721         t = nlmsg_data(nlh);
1722         t->tca_family = AF_UNSPEC;
1723         t->tca__pad1 = 0;
1724         t->tca__pad2 = 0;
1725
1726         nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
1727         if (!nest) {
1728                 NL_SET_ERR_MSG(extack, "Failed to add new netlink message");
1729                 goto out_module_put;
1730         }
1731
1732         err = __tcf_generic_walker(net, skb, &dcb, RTM_DELACTION, ops, extack);
1733         if (err <= 0) {
1734                 nla_nest_cancel(skb, nest);
1735                 goto out_module_put;
1736         }
1737
1738         nla_nest_end(skb, nest);
1739
1740         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1741         nlh->nlmsg_flags |= NLM_F_ROOT;
1742         module_put(ops->owner);
1743         err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1744                              n->nlmsg_flags & NLM_F_ECHO);
1745         if (err < 0)
1746                 NL_SET_ERR_MSG(extack, "Failed to send TC action flush notification");
1747
1748         return err;
1749
1750 out_module_put:
1751         module_put(ops->owner);
1752 err_out:
1753         kfree_skb(skb);
1754         return err;
1755 }
1756
1757 static int tcf_action_delete(struct net *net, struct tc_action *actions[])
1758 {
1759         int i;
1760
1761         for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
1762                 struct tc_action *a = actions[i];
1763                 const struct tc_action_ops *ops = a->ops;
1764                 /* Actions can be deleted concurrently so we must save their
1765                  * type and id to search again after reference is released.
1766                  */
1767                 struct tcf_idrinfo *idrinfo = a->idrinfo;
1768                 u32 act_index = a->tcfa_index;
1769
1770                 actions[i] = NULL;
1771                 if (tcf_action_put(a)) {
1772                         /* last reference, action was deleted concurrently */
1773                         module_put(ops->owner);
1774                 } else  {
1775                         int ret;
1776
1777                         /* now do the delete */
1778                         ret = tcf_idr_delete_index(idrinfo, act_index);
1779                         if (ret < 0)
1780                                 return ret;
1781                 }
1782         }
1783         return 0;
1784 }
1785
1786 static int
1787 tcf_reoffload_del_notify(struct net *net, struct tc_action *action)
1788 {
1789         size_t attr_size = tcf_action_fill_size(action);
1790         struct tc_action *actions[TCA_ACT_MAX_PRIO] = {
1791                 [0] = action,
1792         };
1793         const struct tc_action_ops *ops = action->ops;
1794         struct sk_buff *skb;
1795         int ret;
1796
1797         skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1798                         GFP_KERNEL);
1799         if (!skb)
1800                 return -ENOBUFS;
1801
1802         if (tca_get_fill(skb, actions, 0, 0, 0, RTM_DELACTION, 0, 1) <= 0) {
1803                 kfree_skb(skb);
1804                 return -EINVAL;
1805         }
1806
1807         ret = tcf_idr_release_unsafe(action);
1808         if (ret == ACT_P_DELETED) {
1809                 module_put(ops->owner);
1810                 ret = rtnetlink_send(skb, net, 0, RTNLGRP_TC, 0);
1811         } else {
1812                 kfree_skb(skb);
1813         }
1814
1815         return ret;
1816 }
1817
1818 int tcf_action_reoffload_cb(flow_indr_block_bind_cb_t *cb,
1819                             void *cb_priv, bool add)
1820 {
1821         struct tc_act_pernet_id *id_ptr;
1822         struct tcf_idrinfo *idrinfo;
1823         struct tc_action_net *tn;
1824         struct tc_action *p;
1825         unsigned int act_id;
1826         unsigned long tmp;
1827         unsigned long id;
1828         struct idr *idr;
1829         struct net *net;
1830         int ret;
1831
1832         if (!cb)
1833                 return -EINVAL;
1834
1835         down_read(&net_rwsem);
1836         mutex_lock(&act_id_mutex);
1837
1838         for_each_net(net) {
1839                 list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
1840                         act_id = id_ptr->id;
1841                         tn = net_generic(net, act_id);
1842                         if (!tn)
1843                                 continue;
1844                         idrinfo = tn->idrinfo;
1845                         if (!idrinfo)
1846                                 continue;
1847
1848                         mutex_lock(&idrinfo->lock);
1849                         idr = &idrinfo->action_idr;
1850                         idr_for_each_entry_ul(idr, p, tmp, id) {
1851                                 if (IS_ERR(p) || tc_act_bind(p->tcfa_flags))
1852                                         continue;
1853                                 if (add) {
1854                                         tcf_action_offload_add_ex(p, NULL, cb,
1855                                                                   cb_priv);
1856                                         continue;
1857                                 }
1858
1859                                 /* cb unregister to update hw count */
1860                                 ret = tcf_action_offload_del_ex(p, cb, cb_priv);
1861                                 if (ret < 0)
1862                                         continue;
1863                                 if (tc_act_skip_sw(p->tcfa_flags) &&
1864                                     !tc_act_in_hw(p))
1865                                         tcf_reoffload_del_notify(net, p);
1866                         }
1867                         mutex_unlock(&idrinfo->lock);
1868                 }
1869         }
1870         mutex_unlock(&act_id_mutex);
1871         up_read(&net_rwsem);
1872
1873         return 0;
1874 }
1875
1876 static int
1877 tcf_del_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[],
1878                u32 portid, size_t attr_size, struct netlink_ext_ack *extack)
1879 {
1880         int ret;
1881         struct sk_buff *skb;
1882
1883         skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1884                         GFP_KERNEL);
1885         if (!skb)
1886                 return -ENOBUFS;
1887
1888         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, RTM_DELACTION,
1889                          0, 2) <= 0) {
1890                 NL_SET_ERR_MSG(extack, "Failed to fill netlink TC action attributes");
1891                 kfree_skb(skb);
1892                 return -EINVAL;
1893         }
1894
1895         /* now do the delete */
1896         ret = tcf_action_delete(net, actions);
1897         if (ret < 0) {
1898                 NL_SET_ERR_MSG(extack, "Failed to delete TC action");
1899                 kfree_skb(skb);
1900                 return ret;
1901         }
1902
1903         ret = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1904                              n->nlmsg_flags & NLM_F_ECHO);
1905         return ret;
1906 }
1907
1908 static int
1909 tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
1910               u32 portid, int event, struct netlink_ext_ack *extack)
1911 {
1912         int i, ret;
1913         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1914         struct tc_action *act;
1915         size_t attr_size = 0;
1916         struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
1917
1918         ret = nla_parse_nested_deprecated(tb, TCA_ACT_MAX_PRIO, nla, NULL,
1919                                           extack);
1920         if (ret < 0)
1921                 return ret;
1922
1923         if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) {
1924                 if (tb[1])
1925                         return tca_action_flush(net, tb[1], n, portid, extack);
1926
1927                 NL_SET_ERR_MSG(extack, "Invalid netlink attributes while flushing TC action");
1928                 return -EINVAL;
1929         }
1930
1931         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1932                 act = tcf_action_get_1(net, tb[i], n, portid, extack);
1933                 if (IS_ERR(act)) {
1934                         ret = PTR_ERR(act);
1935                         goto err;
1936                 }
1937                 attr_size += tcf_action_fill_size(act);
1938                 actions[i - 1] = act;
1939         }
1940
1941         attr_size = tcf_action_full_attrs_size(attr_size);
1942
1943         if (event == RTM_GETACTION)
1944                 ret = tcf_get_notify(net, portid, n, actions, event, extack);
1945         else { /* delete */
1946                 ret = tcf_del_notify(net, n, actions, portid, attr_size, extack);
1947                 if (ret)
1948                         goto err;
1949                 return 0;
1950         }
1951 err:
1952         tcf_action_put_many(actions);
1953         return ret;
1954 }
1955
1956 static int
1957 tcf_add_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[],
1958                u32 portid, size_t attr_size, struct netlink_ext_ack *extack)
1959 {
1960         struct sk_buff *skb;
1961
1962         skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1963                         GFP_KERNEL);
1964         if (!skb)
1965                 return -ENOBUFS;
1966
1967         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, n->nlmsg_flags,
1968                          RTM_NEWACTION, 0, 0) <= 0) {
1969                 NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1970                 kfree_skb(skb);
1971                 return -EINVAL;
1972         }
1973
1974         return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1975                               n->nlmsg_flags & NLM_F_ECHO);
1976 }
1977
1978 static int tcf_action_add(struct net *net, struct nlattr *nla,
1979                           struct nlmsghdr *n, u32 portid, u32 flags,
1980                           struct netlink_ext_ack *extack)
1981 {
1982         size_t attr_size = 0;
1983         int loop, ret, i;
1984         struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
1985         int init_res[TCA_ACT_MAX_PRIO] = {};
1986
1987         for (loop = 0; loop < 10; loop++) {
1988                 ret = tcf_action_init(net, NULL, nla, NULL, actions, init_res,
1989                                       &attr_size, flags, 0, extack);
1990                 if (ret != -EAGAIN)
1991                         break;
1992         }
1993
1994         if (ret < 0)
1995                 return ret;
1996         ret = tcf_add_notify(net, n, actions, portid, attr_size, extack);
1997
1998         /* only put existing actions */
1999         for (i = 0; i < TCA_ACT_MAX_PRIO; i++)
2000                 if (init_res[i] == ACT_P_CREATED)
2001                         actions[i] = NULL;
2002         tcf_action_put_many(actions);
2003
2004         return ret;
2005 }
2006
2007 static const struct nla_policy tcaa_policy[TCA_ROOT_MAX + 1] = {
2008         [TCA_ROOT_FLAGS] = NLA_POLICY_BITFIELD32(TCA_ACT_FLAG_LARGE_DUMP_ON |
2009                                                  TCA_ACT_FLAG_TERSE_DUMP),
2010         [TCA_ROOT_TIME_DELTA]      = { .type = NLA_U32 },
2011 };
2012
2013 static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n,
2014                          struct netlink_ext_ack *extack)
2015 {
2016         struct net *net = sock_net(skb->sk);
2017         struct nlattr *tca[TCA_ROOT_MAX + 1];
2018         u32 portid = NETLINK_CB(skb).portid;
2019         u32 flags = 0;
2020         int ret = 0;
2021
2022         if ((n->nlmsg_type != RTM_GETACTION) &&
2023             !netlink_capable(skb, CAP_NET_ADMIN))
2024                 return -EPERM;
2025
2026         ret = nlmsg_parse_deprecated(n, sizeof(struct tcamsg), tca,
2027                                      TCA_ROOT_MAX, NULL, extack);
2028         if (ret < 0)
2029                 return ret;
2030
2031         if (tca[TCA_ACT_TAB] == NULL) {
2032                 NL_SET_ERR_MSG(extack, "Netlink action attributes missing");
2033                 return -EINVAL;
2034         }
2035
2036         /* n->nlmsg_flags & NLM_F_CREATE */
2037         switch (n->nlmsg_type) {
2038         case RTM_NEWACTION:
2039                 /* we are going to assume all other flags
2040                  * imply create only if it doesn't exist
2041                  * Note that CREATE | EXCL implies that
2042                  * but since we want avoid ambiguity (eg when flags
2043                  * is zero) then just set this
2044                  */
2045                 if (n->nlmsg_flags & NLM_F_REPLACE)
2046                         flags = TCA_ACT_FLAGS_REPLACE;
2047                 ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, portid, flags,
2048                                      extack);
2049                 break;
2050         case RTM_DELACTION:
2051                 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
2052                                     portid, RTM_DELACTION, extack);
2053                 break;
2054         case RTM_GETACTION:
2055                 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
2056                                     portid, RTM_GETACTION, extack);
2057                 break;
2058         default:
2059                 BUG();
2060         }
2061
2062         return ret;
2063 }
2064
2065 static struct nlattr *find_dump_kind(struct nlattr **nla)
2066 {
2067         struct nlattr *tb1, *tb2[TCA_ACT_MAX + 1];
2068         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
2069         struct nlattr *kind;
2070
2071         tb1 = nla[TCA_ACT_TAB];
2072         if (tb1 == NULL)
2073                 return NULL;
2074
2075         if (nla_parse_deprecated(tb, TCA_ACT_MAX_PRIO, nla_data(tb1), NLMSG_ALIGN(nla_len(tb1)), NULL, NULL) < 0)
2076                 return NULL;
2077
2078         if (tb[1] == NULL)
2079                 return NULL;
2080         if (nla_parse_nested_deprecated(tb2, TCA_ACT_MAX, tb[1], tcf_action_policy, NULL) < 0)
2081                 return NULL;
2082         kind = tb2[TCA_ACT_KIND];
2083
2084         return kind;
2085 }
2086
2087 static int tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
2088 {
2089         struct net *net = sock_net(skb->sk);
2090         struct nlmsghdr *nlh;
2091         unsigned char *b = skb_tail_pointer(skb);
2092         struct nlattr *nest;
2093         struct tc_action_ops *a_o;
2094         int ret = 0;
2095         struct tcamsg *t = (struct tcamsg *) nlmsg_data(cb->nlh);
2096         struct nlattr *tb[TCA_ROOT_MAX + 1];
2097         struct nlattr *count_attr = NULL;
2098         unsigned long jiffy_since = 0;
2099         struct nlattr *kind = NULL;
2100         struct nla_bitfield32 bf;
2101         u32 msecs_since = 0;
2102         u32 act_count = 0;
2103
2104         ret = nlmsg_parse_deprecated(cb->nlh, sizeof(struct tcamsg), tb,
2105                                      TCA_ROOT_MAX, tcaa_policy, cb->extack);
2106         if (ret < 0)
2107                 return ret;
2108
2109         kind = find_dump_kind(tb);
2110         if (kind == NULL) {
2111                 pr_info("tc_dump_action: action bad kind\n");
2112                 return 0;
2113         }
2114
2115         a_o = tc_lookup_action(kind);
2116         if (a_o == NULL)
2117                 return 0;
2118
2119         cb->args[2] = 0;
2120         if (tb[TCA_ROOT_FLAGS]) {
2121                 bf = nla_get_bitfield32(tb[TCA_ROOT_FLAGS]);
2122                 cb->args[2] = bf.value;
2123         }
2124
2125         if (tb[TCA_ROOT_TIME_DELTA]) {
2126                 msecs_since = nla_get_u32(tb[TCA_ROOT_TIME_DELTA]);
2127         }
2128
2129         nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
2130                         cb->nlh->nlmsg_type, sizeof(*t), 0);
2131         if (!nlh)
2132                 goto out_module_put;
2133
2134         if (msecs_since)
2135                 jiffy_since = jiffies - msecs_to_jiffies(msecs_since);
2136
2137         t = nlmsg_data(nlh);
2138         t->tca_family = AF_UNSPEC;
2139         t->tca__pad1 = 0;
2140         t->tca__pad2 = 0;
2141         cb->args[3] = jiffy_since;
2142         count_attr = nla_reserve(skb, TCA_ROOT_COUNT, sizeof(u32));
2143         if (!count_attr)
2144                 goto out_module_put;
2145
2146         nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
2147         if (nest == NULL)
2148                 goto out_module_put;
2149
2150         ret = __tcf_generic_walker(net, skb, cb, RTM_GETACTION, a_o, NULL);
2151         if (ret < 0)
2152                 goto out_module_put;
2153
2154         if (ret > 0) {
2155                 nla_nest_end(skb, nest);
2156                 ret = skb->len;
2157                 act_count = cb->args[1];
2158                 memcpy(nla_data(count_attr), &act_count, sizeof(u32));
2159                 cb->args[1] = 0;
2160         } else
2161                 nlmsg_trim(skb, b);
2162
2163         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
2164         if (NETLINK_CB(cb->skb).portid && ret)
2165                 nlh->nlmsg_flags |= NLM_F_MULTI;
2166         module_put(a_o->owner);
2167         return skb->len;
2168
2169 out_module_put:
2170         module_put(a_o->owner);
2171         nlmsg_trim(skb, b);
2172         return skb->len;
2173 }
2174
2175 static int __init tc_action_init(void)
2176 {
2177         rtnl_register(PF_UNSPEC, RTM_NEWACTION, tc_ctl_action, NULL, 0);
2178         rtnl_register(PF_UNSPEC, RTM_DELACTION, tc_ctl_action, NULL, 0);
2179         rtnl_register(PF_UNSPEC, RTM_GETACTION, tc_ctl_action, tc_dump_action,
2180                       0);
2181
2182         return 0;
2183 }
2184
2185 subsys_initcall(tc_action_init);