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_generic_walker(struct net *net, struct sk_buff *skb,
 680                                 struct netlink_callback *cb, int type,
 681                                 const struct tc_action_ops *ops,
 682                                 struct netlink_ext_ack *extack)
 683 {
 684         struct tc_action_net *tn = net_generic(net, ops->net_id);
 685
 686         if (unlikely(ops->walk))
 687                 return ops->walk(net, skb, cb, type, ops, extack);
 688
 689         return tcf_generic_walker(tn, skb, cb, type, ops, extack);
 690 }
 691
 692 static int __tcf_idr_search(struct net *net,
 693                             const struct tc_action_ops *ops,
 694                             struct tc_action **a, u32 index)
 695 {
 696         struct tc_action_net *tn = net_generic(net, ops->net_id);
 697
 698         if (unlikely(ops->lookup))
 699                 return ops->lookup(net, a, index);
 700
 701         return tcf_idr_search(tn, a, index);
 702 }
 703
 704 static int tcf_idr_delete_index(struct tcf_idrinfo *idrinfo, u32 index)
 705 {
 706         struct tc_action *p;
 707         int ret = 0;
 708
 709         mutex_lock(&idrinfo->lock);
 710         p = idr_find(&idrinfo->action_idr, index);
 711         if (!p) {
 712                 mutex_unlock(&idrinfo->lock);
 713                 return -ENOENT;
 714         }
 715
 716         if (!atomic_read(&p->tcfa_bindcnt)) {
 717                 if (refcount_dec_and_test(&p->tcfa_refcnt)) {
 718                         struct module *owner = p->ops->owner;
 719
 720                         WARN_ON(p != idr_remove(&idrinfo->action_idr,
 721                                                 p->tcfa_index));
 722                         mutex_unlock(&idrinfo->lock);
 723
 724                         tcf_action_cleanup(p);
 725                         module_put(owner);
 726                         return 0;
 727                 }
 728                 ret = 0;
 729         } else {
 730                 ret = -EPERM;
 731         }
 732
 733         mutex_unlock(&idrinfo->lock);
 734         return ret;
 735 }
 736
 737 int tcf_idr_create(struct tc_action_net *tn, u32 index, struct nlattr *est,
 738                    struct tc_action **a, const struct tc_action_ops *ops,
 739                    int bind, bool cpustats, u32 flags)
 740 {
 741         struct tc_action *p = kzalloc(ops->size, GFP_KERNEL);
 742         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 743         int err = -ENOMEM;
 744
 745         if (unlikely(!p))
 746                 return -ENOMEM;
 747         refcount_set(&p->tcfa_refcnt, 1);
 748         if (bind)
 749                 atomic_set(&p->tcfa_bindcnt, 1);
 750
 751         if (cpustats) {
 752                 p->cpu_bstats = netdev_alloc_pcpu_stats(struct gnet_stats_basic_sync);
 753                 if (!p->cpu_bstats)
 754                         goto err1;
 755                 p->cpu_bstats_hw = netdev_alloc_pcpu_stats(struct gnet_stats_basic_sync);
 756                 if (!p->cpu_bstats_hw)
 757                         goto err2;
 758                 p->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
 759                 if (!p->cpu_qstats)
 760                         goto err3;
 761         }
 762         gnet_stats_basic_sync_init(&p->tcfa_bstats);
 763         gnet_stats_basic_sync_init(&p->tcfa_bstats_hw);
 764         spin_lock_init(&p->tcfa_lock);
 765         p->tcfa_index = index;
 766         p->tcfa_tm.install = jiffies;
 767         p->tcfa_tm.lastuse = jiffies;
 768         p->tcfa_tm.firstuse = 0;
 769         p->tcfa_flags = flags;
 770         if (est) {
 771                 err = gen_new_estimator(&p->tcfa_bstats, p->cpu_bstats,
 772                                         &p->tcfa_rate_est,
 773                                         &p->tcfa_lock, false, est);
 774                 if (err)
 775                         goto err4;
 776         }
 777
 778         p->idrinfo = idrinfo;
 779         __module_get(ops->owner);
 780         p->ops = ops;
 781         *a = p;
 782         return 0;
 783 err4:
 784         free_percpu(p->cpu_qstats);
 785 err3:
 786         free_percpu(p->cpu_bstats_hw);
 787 err2:
 788         free_percpu(p->cpu_bstats);
 789 err1:
 790         kfree(p);
 791         return err;
 792 }
 793 EXPORT_SYMBOL(tcf_idr_create);
 794
 795 int tcf_idr_create_from_flags(struct tc_action_net *tn, u32 index,
 796                               struct nlattr *est, struct tc_action **a,
 797                               const struct tc_action_ops *ops, int bind,
 798                               u32 flags)
 799 {
 800         /* Set cpustats according to actions flags. */
 801         return tcf_idr_create(tn, index, est, a, ops, bind,
 802                               !(flags & TCA_ACT_FLAGS_NO_PERCPU_STATS), flags);
 803 }
 804 EXPORT_SYMBOL(tcf_idr_create_from_flags);
 805
 806 /* Cleanup idr index that was allocated but not initialized. */
 807
 808 void tcf_idr_cleanup(struct tc_action_net *tn, u32 index)
 809 {
 810         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 811
 812         mutex_lock(&idrinfo->lock);
 813         /* Remove ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */
 814         WARN_ON(!IS_ERR(idr_remove(&idrinfo->action_idr, index)));
 815         mutex_unlock(&idrinfo->lock);
 816 }
 817 EXPORT_SYMBOL(tcf_idr_cleanup);
 818
 819 /* Check if action with specified index exists. If actions is found, increments
 820  * its reference and bind counters, and return 1. Otherwise insert temporary
 821  * error pointer (to prevent concurrent users from inserting actions with same
 822  * index) and return 0.
 823  */
 824
 825 int tcf_idr_check_alloc(struct tc_action_net *tn, u32 *index,
 826                         struct tc_action **a, int bind)
 827 {
 828         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 829         struct tc_action *p;
 830         int ret;
 831
 832 again:
 833         mutex_lock(&idrinfo->lock);
 834         if (*index) {
 835                 p = idr_find(&idrinfo->action_idr, *index);
 836                 if (IS_ERR(p)) {
 837                         /* This means that another process allocated
 838                          * index but did not assign the pointer yet.
 839                          */
 840                         mutex_unlock(&idrinfo->lock);
 841                         goto again;
 842                 }
 843
 844                 if (p) {
 845                         refcount_inc(&p->tcfa_refcnt);
 846                         if (bind)
 847                                 atomic_inc(&p->tcfa_bindcnt);
 848                         *a = p;
 849                         ret = 1;
 850                 } else {
 851                         *a = NULL;
 852                         ret = idr_alloc_u32(&idrinfo->action_idr, NULL, index,
 853                                             *index, GFP_KERNEL);
 854                         if (!ret)
 855                                 idr_replace(&idrinfo->action_idr,
 856                                             ERR_PTR(-EBUSY), *index);
 857                 }
 858         } else {
 859                 *index = 1;
 860                 *a = NULL;
 861                 ret = idr_alloc_u32(&idrinfo->action_idr, NULL, index,
 862                                     UINT_MAX, GFP_KERNEL);
 863                 if (!ret)
 864                         idr_replace(&idrinfo->action_idr, ERR_PTR(-EBUSY),
 865                                     *index);
 866         }
 867         mutex_unlock(&idrinfo->lock);
 868         return ret;
 869 }
 870 EXPORT_SYMBOL(tcf_idr_check_alloc);
 871
 872 void tcf_idrinfo_destroy(const struct tc_action_ops *ops,
 873                          struct tcf_idrinfo *idrinfo)
 874 {
 875         struct idr *idr = &idrinfo->action_idr;
 876         struct tc_action *p;
 877         int ret;
 878         unsigned long id = 1;
 879         unsigned long tmp;
 880
 881         idr_for_each_entry_ul(idr, p, tmp, id) {
 882                 ret = __tcf_idr_release(p, false, true);
 883                 if (ret == ACT_P_DELETED)
 884                         module_put(ops->owner);
 885                 else if (ret < 0)
 886                         return;
 887         }
 888         idr_destroy(&idrinfo->action_idr);
 889 }
 890 EXPORT_SYMBOL(tcf_idrinfo_destroy);
 891
 892 static LIST_HEAD(act_base);
 893 static DEFINE_RWLOCK(act_mod_lock);
 894 /* since act ops id is stored in pernet subsystem list,
 895  * then there is no way to walk through only all the action
 896  * subsystem, so we keep tc action pernet ops id for
 897  * reoffload to walk through.
 898  */
 899 static LIST_HEAD(act_pernet_id_list);
 900 static DEFINE_MUTEX(act_id_mutex);
 901 struct tc_act_pernet_id {
 902         struct list_head list;
 903         unsigned int id;
 904 };
 905
 906 static int tcf_pernet_add_id_list(unsigned int id)
 907 {
 908         struct tc_act_pernet_id *id_ptr;
 909         int ret = 0;
 910
 911         mutex_lock(&act_id_mutex);
 912         list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
 913                 if (id_ptr->id == id) {
 914                         ret = -EEXIST;
 915                         goto err_out;
 916                 }
 917         }
 918
 919         id_ptr = kzalloc(sizeof(*id_ptr), GFP_KERNEL);
 920         if (!id_ptr) {
 921                 ret = -ENOMEM;
 922                 goto err_out;
 923         }
 924         id_ptr->id = id;
 925
 926         list_add_tail(&id_ptr->list, &act_pernet_id_list);
 927
 928 err_out:
 929         mutex_unlock(&act_id_mutex);
 930         return ret;
 931 }
 932
 933 static void tcf_pernet_del_id_list(unsigned int id)
 934 {
 935         struct tc_act_pernet_id *id_ptr;
 936
 937         mutex_lock(&act_id_mutex);
 938         list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
 939                 if (id_ptr->id == id) {
 940                         list_del(&id_ptr->list);
 941                         kfree(id_ptr);
 942                         break;
 943                 }
 944         }
 945         mutex_unlock(&act_id_mutex);
 946 }
 947
 948 int tcf_register_action(struct tc_action_ops *act,
 949                         struct pernet_operations *ops)
 950 {
 951         struct tc_action_ops *a;
 952         int ret;
 953
 954         if (!act->act || !act->dump || !act->init)
 955                 return -EINVAL;
 956
 957         /* We have to register pernet ops before making the action ops visible,
 958          * otherwise tcf_action_init_1() could get a partially initialized
 959          * netns.
 960          */
 961         ret = register_pernet_subsys(ops);
 962         if (ret)
 963                 return ret;
 964
 965         if (ops->id) {
 966                 ret = tcf_pernet_add_id_list(*ops->id);
 967                 if (ret)
 968                         goto err_id;
 969         }
 970
 971         write_lock(&act_mod_lock);
 972         list_for_each_entry(a, &act_base, head) {
 973                 if (act->id == a->id || (strcmp(act->kind, a->kind) == 0)) {
 974                         ret = -EEXIST;
 975                         goto err_out;
 976                 }
 977         }
 978         list_add_tail(&act->head, &act_base);
 979         write_unlock(&act_mod_lock);
 980
 981         return 0;
 982
 983 err_out:
 984         write_unlock(&act_mod_lock);
 985         if (ops->id)
 986                 tcf_pernet_del_id_list(*ops->id);
 987 err_id:
 988         unregister_pernet_subsys(ops);
 989         return ret;
 990 }
 991 EXPORT_SYMBOL(tcf_register_action);
 992
 993 int tcf_unregister_action(struct tc_action_ops *act,
 994                           struct pernet_operations *ops)
 995 {
 996         struct tc_action_ops *a;
 997         int err = -ENOENT;
 998
 999         write_lock(&act_mod_lock);
1000         list_for_each_entry(a, &act_base, head) {
1001                 if (a == act) {
1002                         list_del(&act->head);
1003                         err = 0;
1004                         break;
1005                 }
1006         }
1007         write_unlock(&act_mod_lock);
1008         if (!err) {
1009                 unregister_pernet_subsys(ops);
1010                 if (ops->id)
1011                         tcf_pernet_del_id_list(*ops->id);
1012         }
1013         return err;
1014 }
1015 EXPORT_SYMBOL(tcf_unregister_action);
1016
1017 /* lookup by name */
1018 static struct tc_action_ops *tc_lookup_action_n(char *kind)
1019 {
1020         struct tc_action_ops *a, *res = NULL;
1021
1022         if (kind) {
1023                 read_lock(&act_mod_lock);
1024                 list_for_each_entry(a, &act_base, head) {
1025                         if (strcmp(kind, a->kind) == 0) {
1026                                 if (try_module_get(a->owner))
1027                                         res = a;
1028                                 break;
1029                         }
1030                 }
1031                 read_unlock(&act_mod_lock);
1032         }
1033         return res;
1034 }
1035
1036 /* lookup by nlattr */
1037 static struct tc_action_ops *tc_lookup_action(struct nlattr *kind)
1038 {
1039         struct tc_action_ops *a, *res = NULL;
1040
1041         if (kind) {
1042                 read_lock(&act_mod_lock);
1043                 list_for_each_entry(a, &act_base, head) {
1044                         if (nla_strcmp(kind, a->kind) == 0) {
1045                                 if (try_module_get(a->owner))
1046                                         res = a;
1047                                 break;
1048                         }
1049                 }
1050                 read_unlock(&act_mod_lock);
1051         }
1052         return res;
1053 }
1054
1055 /*TCA_ACT_MAX_PRIO is 32, there count up to 32 */
1056 #define TCA_ACT_MAX_PRIO_MASK 0x1FF
1057 int tcf_action_exec(struct sk_buff *skb, struct tc_action **actions,
1058                     int nr_actions, struct tcf_result *res)
1059 {
1060         u32 jmp_prgcnt = 0;
1061         u32 jmp_ttl = TCA_ACT_MAX_PRIO; /*matches actions per filter */
1062         int i;
1063         int ret = TC_ACT_OK;
1064
1065         if (skb_skip_tc_classify(skb))
1066                 return TC_ACT_OK;
1067
1068 restart_act_graph:
1069         for (i = 0; i < nr_actions; i++) {
1070                 const struct tc_action *a = actions[i];
1071                 int repeat_ttl;
1072
1073                 if (jmp_prgcnt > 0) {
1074                         jmp_prgcnt -= 1;
1075                         continue;
1076                 }
1077
1078                 if (tc_act_skip_sw(a->tcfa_flags))
1079                         continue;
1080
1081                 repeat_ttl = 32;
1082 repeat:
1083                 ret = a->ops->act(skb, a, res);
1084                 if (unlikely(ret == TC_ACT_REPEAT)) {
1085                         if (--repeat_ttl != 0)
1086                                 goto repeat;
1087                         /* suspicious opcode, stop pipeline */
1088                         net_warn_ratelimited("TC_ACT_REPEAT abuse ?\n");
1089                         return TC_ACT_OK;
1090                 }
1091                 if (TC_ACT_EXT_CMP(ret, TC_ACT_JUMP)) {
1092                         jmp_prgcnt = ret & TCA_ACT_MAX_PRIO_MASK;
1093                         if (!jmp_prgcnt || (jmp_prgcnt > nr_actions)) {
1094                                 /* faulty opcode, stop pipeline */
1095                                 return TC_ACT_OK;
1096                         } else {
1097                                 jmp_ttl -= 1;
1098                                 if (jmp_ttl > 0)
1099                                         goto restart_act_graph;
1100                                 else /* faulty graph, stop pipeline */
1101                                         return TC_ACT_OK;
1102                         }
1103                 } else if (TC_ACT_EXT_CMP(ret, TC_ACT_GOTO_CHAIN)) {
1104                         if (unlikely(!rcu_access_pointer(a->goto_chain))) {
1105                                 net_warn_ratelimited("can't go to NULL chain!\n");
1106                                 return TC_ACT_SHOT;
1107                         }
1108                         tcf_action_goto_chain_exec(a, res);
1109                 }
1110
1111                 if (ret != TC_ACT_PIPE)
1112                         break;
1113         }
1114
1115         return ret;
1116 }
1117 EXPORT_SYMBOL(tcf_action_exec);
1118
1119 int tcf_action_destroy(struct tc_action *actions[], int bind)
1120 {
1121         const struct tc_action_ops *ops;
1122         struct tc_action *a;
1123         int ret = 0, i;
1124
1125         for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
1126                 a = actions[i];
1127                 actions[i] = NULL;
1128                 ops = a->ops;
1129                 ret = __tcf_idr_release(a, bind, true);
1130                 if (ret == ACT_P_DELETED)
1131                         module_put(ops->owner);
1132                 else if (ret < 0)
1133                         return ret;
1134         }
1135         return ret;
1136 }
1137
1138 static int tcf_action_put(struct tc_action *p)
1139 {
1140         return __tcf_action_put(p, false);
1141 }
1142
1143 /* Put all actions in this array, skip those NULL's. */
1144 static void tcf_action_put_many(struct tc_action *actions[])
1145 {
1146         int i;
1147
1148         for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
1149                 struct tc_action *a = actions[i];
1150                 const struct tc_action_ops *ops;
1151
1152                 if (!a)
1153                         continue;
1154                 ops = a->ops;
1155                 if (tcf_action_put(a))
1156                         module_put(ops->owner);
1157         }
1158 }
1159
1160 int
1161 tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
1162 {
1163         return a->ops->dump(skb, a, bind, ref);
1164 }
1165
1166 int
1167 tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
1168 {
1169         int err = -EINVAL;
1170         unsigned char *b = skb_tail_pointer(skb);
1171         struct nlattr *nest;
1172         u32 flags;
1173
1174         if (tcf_action_dump_terse(skb, a, false))
1175                 goto nla_put_failure;
1176
1177         if (a->hw_stats != TCA_ACT_HW_STATS_ANY &&
1178             nla_put_bitfield32(skb, TCA_ACT_HW_STATS,
1179                                a->hw_stats, TCA_ACT_HW_STATS_ANY))
1180                 goto nla_put_failure;
1181
1182         if (a->used_hw_stats_valid &&
1183             nla_put_bitfield32(skb, TCA_ACT_USED_HW_STATS,
1184                                a->used_hw_stats, TCA_ACT_HW_STATS_ANY))
1185                 goto nla_put_failure;
1186
1187         flags = a->tcfa_flags & TCA_ACT_FLAGS_USER_MASK;
1188         if (flags &&
1189             nla_put_bitfield32(skb, TCA_ACT_FLAGS,
1190                                flags, flags))
1191                 goto nla_put_failure;
1192
1193         if (nla_put_u32(skb, TCA_ACT_IN_HW_COUNT, a->in_hw_count))
1194                 goto nla_put_failure;
1195
1196         nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
1197         if (nest == NULL)
1198                 goto nla_put_failure;
1199         err = tcf_action_dump_old(skb, a, bind, ref);
1200         if (err > 0) {
1201                 nla_nest_end(skb, nest);
1202                 return err;
1203         }
1204
1205 nla_put_failure:
1206         nlmsg_trim(skb, b);
1207         return -1;
1208 }
1209 EXPORT_SYMBOL(tcf_action_dump_1);
1210
1211 int tcf_action_dump(struct sk_buff *skb, struct tc_action *actions[],
1212                     int bind, int ref, bool terse)
1213 {
1214         struct tc_action *a;
1215         int err = -EINVAL, i;
1216         struct nlattr *nest;
1217
1218         for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
1219                 a = actions[i];
1220                 nest = nla_nest_start_noflag(skb, i + 1);
1221                 if (nest == NULL)
1222                         goto nla_put_failure;
1223                 err = terse ? tcf_action_dump_terse(skb, a, false) :
1224                         tcf_action_dump_1(skb, a, bind, ref);
1225                 if (err < 0)
1226                         goto errout;
1227                 nla_nest_end(skb, nest);
1228         }
1229
1230         return 0;
1231
1232 nla_put_failure:
1233         err = -EINVAL;
1234 errout:
1235         nla_nest_cancel(skb, nest);
1236         return err;
1237 }
1238
1239 static struct tc_cookie *nla_memdup_cookie(struct nlattr **tb)
1240 {
1241         struct tc_cookie *c = kzalloc(sizeof(*c), GFP_KERNEL);
1242         if (!c)
1243                 return NULL;
1244
1245         c->data = nla_memdup(tb[TCA_ACT_COOKIE], GFP_KERNEL);
1246         if (!c->data) {
1247                 kfree(c);
1248                 return NULL;
1249         }
1250         c->len = nla_len(tb[TCA_ACT_COOKIE]);
1251
1252         return c;
1253 }
1254
1255 static u8 tcf_action_hw_stats_get(struct nlattr *hw_stats_attr)
1256 {
1257         struct nla_bitfield32 hw_stats_bf;
1258
1259         /* If the user did not pass the attr, that means he does
1260          * not care about the type. Return "any" in that case
1261          * which is setting on all supported types.
1262          */
1263         if (!hw_stats_attr)
1264                 return TCA_ACT_HW_STATS_ANY;
1265         hw_stats_bf = nla_get_bitfield32(hw_stats_attr);
1266         return hw_stats_bf.value;
1267 }
1268
1269 static const struct nla_policy tcf_action_policy[TCA_ACT_MAX + 1] = {
1270         [TCA_ACT_KIND]          = { .type = NLA_STRING },
1271         [TCA_ACT_INDEX]         = { .type = NLA_U32 },
1272         [TCA_ACT_COOKIE]        = { .type = NLA_BINARY,
1273                                     .len = TC_COOKIE_MAX_SIZE },
1274         [TCA_ACT_OPTIONS]       = { .type = NLA_NESTED },
1275         [TCA_ACT_FLAGS]         = NLA_POLICY_BITFIELD32(TCA_ACT_FLAGS_NO_PERCPU_STATS |
1276                                                         TCA_ACT_FLAGS_SKIP_HW |
1277                                                         TCA_ACT_FLAGS_SKIP_SW),
1278         [TCA_ACT_HW_STATS]      = NLA_POLICY_BITFIELD32(TCA_ACT_HW_STATS_ANY),
1279 };
1280
1281 void tcf_idr_insert_many(struct tc_action *actions[])
1282 {
1283         int i;
1284
1285         for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
1286                 struct tc_action *a = actions[i];
1287                 struct tcf_idrinfo *idrinfo;
1288
1289                 if (!a)
1290                         continue;
1291                 idrinfo = a->idrinfo;
1292                 mutex_lock(&idrinfo->lock);
1293                 /* Replace ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc if
1294                  * it is just created, otherwise this is just a nop.
1295                  */
1296                 idr_replace(&idrinfo->action_idr, a, a->tcfa_index);
1297                 mutex_unlock(&idrinfo->lock);
1298         }
1299 }
1300
1301 struct tc_action_ops *tc_action_load_ops(struct nlattr *nla, bool police,
1302                                          bool rtnl_held,
1303                                          struct netlink_ext_ack *extack)
1304 {
1305         struct nlattr *tb[TCA_ACT_MAX + 1];
1306         struct tc_action_ops *a_o;
1307         char act_name[IFNAMSIZ];
1308         struct nlattr *kind;
1309         int err;
1310
1311         if (!police) {
1312                 err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1313                                                   tcf_action_policy, extack);
1314                 if (err < 0)
1315                         return ERR_PTR(err);
1316                 err = -EINVAL;
1317                 kind = tb[TCA_ACT_KIND];
1318                 if (!kind) {
1319                         NL_SET_ERR_MSG(extack, "TC action kind must be specified");
1320                         return ERR_PTR(err);
1321                 }
1322                 if (nla_strscpy(act_name, kind, IFNAMSIZ) < 0) {
1323                         NL_SET_ERR_MSG(extack, "TC action name too long");
1324                         return ERR_PTR(err);
1325                 }
1326         } else {
1327                 if (strlcpy(act_name, "police", IFNAMSIZ) >= IFNAMSIZ) {
1328                         NL_SET_ERR_MSG(extack, "TC action name too long");
1329                         return ERR_PTR(-EINVAL);
1330                 }
1331         }
1332
1333         a_o = tc_lookup_action_n(act_name);
1334         if (a_o == NULL) {
1335 #ifdef CONFIG_MODULES
1336                 if (rtnl_held)
1337                         rtnl_unlock();
1338                 request_module("act_%s", act_name);
1339                 if (rtnl_held)
1340                         rtnl_lock();
1341
1342                 a_o = tc_lookup_action_n(act_name);
1343
1344                 /* We dropped the RTNL semaphore in order to
1345                  * perform the module load.  So, even if we
1346                  * succeeded in loading the module we have to
1347                  * tell the caller to replay the request.  We
1348                  * indicate this using -EAGAIN.
1349                  */
1350                 if (a_o != NULL) {
1351                         module_put(a_o->owner);
1352                         return ERR_PTR(-EAGAIN);
1353                 }
1354 #endif
1355                 NL_SET_ERR_MSG(extack, "Failed to load TC action module");
1356                 return ERR_PTR(-ENOENT);
1357         }
1358
1359         return a_o;
1360 }
1361
1362 struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
1363                                     struct nlattr *nla, struct nlattr *est,
1364                                     struct tc_action_ops *a_o, int *init_res,
1365                                     u32 flags, struct netlink_ext_ack *extack)
1366 {
1367         bool police = flags & TCA_ACT_FLAGS_POLICE;
1368         struct nla_bitfield32 userflags = { 0, 0 };
1369         u8 hw_stats = TCA_ACT_HW_STATS_ANY;
1370         struct nlattr *tb[TCA_ACT_MAX + 1];
1371         struct tc_cookie *cookie = NULL;
1372         struct tc_action *a;
1373         int err;
1374
1375         /* backward compatibility for policer */
1376         if (!police) {
1377                 err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1378                                                   tcf_action_policy, extack);
1379                 if (err < 0)
1380                         return ERR_PTR(err);
1381                 if (tb[TCA_ACT_COOKIE]) {
1382                         cookie = nla_memdup_cookie(tb);
1383                         if (!cookie) {
1384                                 NL_SET_ERR_MSG(extack, "No memory to generate TC cookie");
1385                                 err = -ENOMEM;
1386                                 goto err_out;
1387                         }
1388                 }
1389                 hw_stats = tcf_action_hw_stats_get(tb[TCA_ACT_HW_STATS]);
1390                 if (tb[TCA_ACT_FLAGS]) {
1391                         userflags = nla_get_bitfield32(tb[TCA_ACT_FLAGS]);
1392                         if (!tc_act_flags_valid(userflags.value)) {
1393                                 err = -EINVAL;
1394                                 goto err_out;
1395                         }
1396                 }
1397
1398                 err = a_o->init(net, tb[TCA_ACT_OPTIONS], est, &a, tp,
1399                                 userflags.value | flags, extack);
1400         } else {
1401                 err = a_o->init(net, nla, est, &a, tp, userflags.value | flags,
1402                                 extack);
1403         }
1404         if (err < 0)
1405                 goto err_out;
1406         *init_res = err;
1407
1408         if (!police && tb[TCA_ACT_COOKIE])
1409                 tcf_set_action_cookie(&a->act_cookie, cookie);
1410
1411         if (!police)
1412                 a->hw_stats = hw_stats;
1413
1414         return a;
1415
1416 err_out:
1417         if (cookie) {
1418                 kfree(cookie->data);
1419                 kfree(cookie);
1420         }
1421         return ERR_PTR(err);
1422 }
1423
1424 static bool tc_act_bind(u32 flags)
1425 {
1426         return !!(flags & TCA_ACT_FLAGS_BIND);
1427 }
1428
1429 /* Returns numbers of initialized actions or negative error. */
1430
1431 int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla,
1432                     struct nlattr *est, struct tc_action *actions[],
1433                     int init_res[], size_t *attr_size,
1434                     u32 flags, u32 fl_flags,
1435                     struct netlink_ext_ack *extack)
1436 {
1437         struct tc_action_ops *ops[TCA_ACT_MAX_PRIO] = {};
1438         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1439         struct tc_action *act;
1440         size_t sz = 0;
1441         int err;
1442         int i;
1443
1444         err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX_PRIO, nla, NULL,
1445                                           extack);
1446         if (err < 0)
1447                 return err;
1448
1449         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1450                 struct tc_action_ops *a_o;
1451
1452                 a_o = tc_action_load_ops(tb[i], flags & TCA_ACT_FLAGS_POLICE,
1453                                          !(flags & TCA_ACT_FLAGS_NO_RTNL),
1454                                          extack);
1455                 if (IS_ERR(a_o)) {
1456                         err = PTR_ERR(a_o);
1457                         goto err_mod;
1458                 }
1459                 ops[i - 1] = a_o;
1460         }
1461
1462         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1463                 act = tcf_action_init_1(net, tp, tb[i], est, ops[i - 1],
1464                                         &init_res[i - 1], flags, extack);
1465                 if (IS_ERR(act)) {
1466                         err = PTR_ERR(act);
1467                         goto err;
1468                 }
1469                 sz += tcf_action_fill_size(act);
1470                 /* Start from index 0 */
1471                 actions[i - 1] = act;
1472                 if (tc_act_bind(flags)) {
1473                         bool skip_sw = tc_skip_sw(fl_flags);
1474                         bool skip_hw = tc_skip_hw(fl_flags);
1475
1476                         if (tc_act_bind(act->tcfa_flags))
1477                                 continue;
1478                         if (skip_sw != tc_act_skip_sw(act->tcfa_flags) ||
1479                             skip_hw != tc_act_skip_hw(act->tcfa_flags)) {
1480                                 NL_SET_ERR_MSG(extack,
1481                                                "Mismatch between action and filter offload flags");
1482                                 err = -EINVAL;
1483                                 goto err;
1484                         }
1485                 } else {
1486                         err = tcf_action_offload_add(act, extack);
1487                         if (tc_act_skip_sw(act->tcfa_flags) && err)
1488                                 goto err;
1489                 }
1490         }
1491
1492         /* We have to commit them all together, because if any error happened in
1493          * between, we could not handle the failure gracefully.
1494          */
1495         tcf_idr_insert_many(actions);
1496
1497         *attr_size = tcf_action_full_attrs_size(sz);
1498         err = i - 1;
1499         goto err_mod;
1500
1501 err:
1502         tcf_action_destroy(actions, flags & TCA_ACT_FLAGS_BIND);
1503 err_mod:
1504         for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
1505                 if (ops[i])
1506                         module_put(ops[i]->owner);
1507         }
1508         return err;
1509 }
1510
1511 void tcf_action_update_stats(struct tc_action *a, u64 bytes, u64 packets,
1512                              u64 drops, bool hw)
1513 {
1514         if (a->cpu_bstats) {
1515                 _bstats_update(this_cpu_ptr(a->cpu_bstats), bytes, packets);
1516
1517                 this_cpu_ptr(a->cpu_qstats)->drops += drops;
1518
1519                 if (hw)
1520                         _bstats_update(this_cpu_ptr(a->cpu_bstats_hw),
1521                                        bytes, packets);
1522                 return;
1523         }
1524
1525         _bstats_update(&a->tcfa_bstats, bytes, packets);
1526         a->tcfa_qstats.drops += drops;
1527         if (hw)
1528                 _bstats_update(&a->tcfa_bstats_hw, bytes, packets);
1529 }
1530 EXPORT_SYMBOL(tcf_action_update_stats);
1531
1532 int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *p,
1533                           int compat_mode)
1534 {
1535         int err = 0;
1536         struct gnet_dump d;
1537
1538         if (p == NULL)
1539                 goto errout;
1540
1541         /* update hw stats for this action */
1542         tcf_action_update_hw_stats(p);
1543
1544         /* compat_mode being true specifies a call that is supposed
1545          * to add additional backward compatibility statistic TLVs.
1546          */
1547         if (compat_mode) {
1548                 if (p->type == TCA_OLD_COMPAT)
1549                         err = gnet_stats_start_copy_compat(skb, 0,
1550                                                            TCA_STATS,
1551                                                            TCA_XSTATS,
1552                                                            &p->tcfa_lock, &d,
1553                                                            TCA_PAD);
1554                 else
1555                         return 0;
1556         } else
1557                 err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
1558                                             &p->tcfa_lock, &d, TCA_ACT_PAD);
1559
1560         if (err < 0)
1561                 goto errout;
1562
1563         if (gnet_stats_copy_basic(&d, p->cpu_bstats,
1564                                   &p->tcfa_bstats, false) < 0 ||
1565             gnet_stats_copy_basic_hw(&d, p->cpu_bstats_hw,
1566                                      &p->tcfa_bstats_hw, false) < 0 ||
1567             gnet_stats_copy_rate_est(&d, &p->tcfa_rate_est) < 0 ||
1568             gnet_stats_copy_queue(&d, p->cpu_qstats,
1569                                   &p->tcfa_qstats,
1570                                   p->tcfa_qstats.qlen) < 0)
1571                 goto errout;
1572
1573         if (gnet_stats_finish_copy(&d) < 0)
1574                 goto errout;
1575
1576         return 0;
1577
1578 errout:
1579         return -1;
1580 }
1581
1582 static int tca_get_fill(struct sk_buff *skb, struct tc_action *actions[],
1583                         u32 portid, u32 seq, u16 flags, int event, int bind,
1584                         int ref)
1585 {
1586         struct tcamsg *t;
1587         struct nlmsghdr *nlh;
1588         unsigned char *b = skb_tail_pointer(skb);
1589         struct nlattr *nest;
1590
1591         nlh = nlmsg_put(skb, portid, seq, event, sizeof(*t), flags);
1592         if (!nlh)
1593                 goto out_nlmsg_trim;
1594         t = nlmsg_data(nlh);
1595         t->tca_family = AF_UNSPEC;
1596         t->tca__pad1 = 0;
1597         t->tca__pad2 = 0;
1598
1599         nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
1600         if (!nest)
1601                 goto out_nlmsg_trim;
1602
1603         if (tcf_action_dump(skb, actions, bind, ref, false) < 0)
1604                 goto out_nlmsg_trim;
1605
1606         nla_nest_end(skb, nest);
1607
1608         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1609         return skb->len;
1610
1611 out_nlmsg_trim:
1612         nlmsg_trim(skb, b);
1613         return -1;
1614 }
1615
1616 static int
1617 tcf_get_notify(struct net *net, u32 portid, struct nlmsghdr *n,
1618                struct tc_action *actions[], int event,
1619                struct netlink_ext_ack *extack)
1620 {
1621         struct sk_buff *skb;
1622
1623         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1624         if (!skb)
1625                 return -ENOBUFS;
1626         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, event,
1627                          0, 1) <= 0) {
1628                 NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1629                 kfree_skb(skb);
1630                 return -EINVAL;
1631         }
1632
1633         return rtnl_unicast(skb, net, portid);
1634 }
1635
1636 static struct tc_action *tcf_action_get_1(struct net *net, struct nlattr *nla,
1637                                           struct nlmsghdr *n, u32 portid,
1638                                           struct netlink_ext_ack *extack)
1639 {
1640         struct nlattr *tb[TCA_ACT_MAX + 1];
1641         const struct tc_action_ops *ops;
1642         struct tc_action *a;
1643         int index;
1644         int err;
1645
1646         err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1647                                           tcf_action_policy, extack);
1648         if (err < 0)
1649                 goto err_out;
1650
1651         err = -EINVAL;
1652         if (tb[TCA_ACT_INDEX] == NULL ||
1653             nla_len(tb[TCA_ACT_INDEX]) < sizeof(index)) {
1654                 NL_SET_ERR_MSG(extack, "Invalid TC action index value");
1655                 goto err_out;
1656         }
1657         index = nla_get_u32(tb[TCA_ACT_INDEX]);
1658
1659         err = -EINVAL;
1660         ops = tc_lookup_action(tb[TCA_ACT_KIND]);
1661         if (!ops) { /* could happen in batch of actions */
1662                 NL_SET_ERR_MSG(extack, "Specified TC action kind not found");
1663                 goto err_out;
1664         }
1665         err = -ENOENT;
1666         if (__tcf_idr_search(net, ops, &a, index) == 0) {
1667                 NL_SET_ERR_MSG(extack, "TC action with specified index not found");
1668                 goto err_mod;
1669         }
1670
1671         module_put(ops->owner);
1672         return a;
1673
1674 err_mod:
1675         module_put(ops->owner);
1676 err_out:
1677         return ERR_PTR(err);
1678 }
1679
1680 static int tca_action_flush(struct net *net, struct nlattr *nla,
1681                             struct nlmsghdr *n, u32 portid,
1682                             struct netlink_ext_ack *extack)
1683 {
1684         struct sk_buff *skb;
1685         unsigned char *b;
1686         struct nlmsghdr *nlh;
1687         struct tcamsg *t;
1688         struct netlink_callback dcb;
1689         struct nlattr *nest;
1690         struct nlattr *tb[TCA_ACT_MAX + 1];
1691         const struct tc_action_ops *ops;
1692         struct nlattr *kind;
1693         int err = -ENOMEM;
1694
1695         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1696         if (!skb)
1697                 return err;
1698
1699         b = skb_tail_pointer(skb);
1700
1701         err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1702                                           tcf_action_policy, extack);
1703         if (err < 0)
1704                 goto err_out;
1705
1706         err = -EINVAL;
1707         kind = tb[TCA_ACT_KIND];
1708         ops = tc_lookup_action(kind);
1709         if (!ops) { /*some idjot trying to flush unknown action */
1710                 NL_SET_ERR_MSG(extack, "Cannot flush unknown TC action");
1711                 goto err_out;
1712         }
1713
1714         nlh = nlmsg_put(skb, portid, n->nlmsg_seq, RTM_DELACTION,
1715                         sizeof(*t), 0);
1716         if (!nlh) {
1717                 NL_SET_ERR_MSG(extack, "Failed to create TC action flush notification");
1718                 goto out_module_put;
1719         }
1720         t = nlmsg_data(nlh);
1721         t->tca_family = AF_UNSPEC;
1722         t->tca__pad1 = 0;
1723         t->tca__pad2 = 0;
1724
1725         nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
1726         if (!nest) {
1727                 NL_SET_ERR_MSG(extack, "Failed to add new netlink message");
1728                 goto out_module_put;
1729         }
1730
1731         err = __tcf_generic_walker(net, skb, &dcb, RTM_DELACTION, ops, extack);
1732         if (err <= 0) {
1733                 nla_nest_cancel(skb, nest);
1734                 goto out_module_put;
1735         }
1736
1737         nla_nest_end(skb, nest);
1738
1739         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1740         nlh->nlmsg_flags |= NLM_F_ROOT;
1741         module_put(ops->owner);
1742         err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1743                              n->nlmsg_flags & NLM_F_ECHO);
1744         if (err < 0)
1745                 NL_SET_ERR_MSG(extack, "Failed to send TC action flush notification");
1746
1747         return err;
1748
1749 out_module_put:
1750         module_put(ops->owner);
1751 err_out:
1752         kfree_skb(skb);
1753         return err;
1754 }
1755
1756 static int tcf_action_delete(struct net *net, struct tc_action *actions[])
1757 {
1758         int i;
1759
1760         for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
1761                 struct tc_action *a = actions[i];
1762                 const struct tc_action_ops *ops = a->ops;
1763                 /* Actions can be deleted concurrently so we must save their
1764                  * type and id to search again after reference is released.
1765                  */
1766                 struct tcf_idrinfo *idrinfo = a->idrinfo;
1767                 u32 act_index = a->tcfa_index;
1768
1769                 actions[i] = NULL;
1770                 if (tcf_action_put(a)) {
1771                         /* last reference, action was deleted concurrently */
1772                         module_put(ops->owner);
1773                 } else  {
1774                         int ret;
1775
1776                         /* now do the delete */
1777                         ret = tcf_idr_delete_index(idrinfo, act_index);
1778                         if (ret < 0)
1779                                 return ret;
1780                 }
1781         }
1782         return 0;
1783 }
1784
1785 static int
1786 tcf_reoffload_del_notify(struct net *net, struct tc_action *action)
1787 {
1788         size_t attr_size = tcf_action_fill_size(action);
1789         struct tc_action *actions[TCA_ACT_MAX_PRIO] = {
1790                 [0] = action,
1791         };
1792         const struct tc_action_ops *ops = action->ops;
1793         struct sk_buff *skb;
1794         int ret;
1795
1796         skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1797                         GFP_KERNEL);
1798         if (!skb)
1799                 return -ENOBUFS;
1800
1801         if (tca_get_fill(skb, actions, 0, 0, 0, RTM_DELACTION, 0, 1) <= 0) {
1802                 kfree_skb(skb);
1803                 return -EINVAL;
1804         }
1805
1806         ret = tcf_idr_release_unsafe(action);
1807         if (ret == ACT_P_DELETED) {
1808                 module_put(ops->owner);
1809                 ret = rtnetlink_send(skb, net, 0, RTNLGRP_TC, 0);
1810         } else {
1811                 kfree_skb(skb);
1812         }
1813
1814         return ret;
1815 }
1816
1817 int tcf_action_reoffload_cb(flow_indr_block_bind_cb_t *cb,
1818                             void *cb_priv, bool add)
1819 {
1820         struct tc_act_pernet_id *id_ptr;
1821         struct tcf_idrinfo *idrinfo;
1822         struct tc_action_net *tn;
1823         struct tc_action *p;
1824         unsigned int act_id;
1825         unsigned long tmp;
1826         unsigned long id;
1827         struct idr *idr;
1828         struct net *net;
1829         int ret;
1830
1831         if (!cb)
1832                 return -EINVAL;
1833
1834         down_read(&net_rwsem);
1835         mutex_lock(&act_id_mutex);
1836
1837         for_each_net(net) {
1838                 list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
1839                         act_id = id_ptr->id;
1840                         tn = net_generic(net, act_id);
1841                         if (!tn)
1842                                 continue;
1843                         idrinfo = tn->idrinfo;
1844                         if (!idrinfo)
1845                                 continue;
1846
1847                         mutex_lock(&idrinfo->lock);
1848                         idr = &idrinfo->action_idr;
1849                         idr_for_each_entry_ul(idr, p, tmp, id) {
1850                                 if (IS_ERR(p) || tc_act_bind(p->tcfa_flags))
1851                                         continue;
1852                                 if (add) {
1853                                         tcf_action_offload_add_ex(p, NULL, cb,
1854                                                                   cb_priv);
1855                                         continue;
1856                                 }
1857
1858                                 /* cb unregister to update hw count */
1859                                 ret = tcf_action_offload_del_ex(p, cb, cb_priv);
1860                                 if (ret < 0)
1861                                         continue;
1862                                 if (tc_act_skip_sw(p->tcfa_flags) &&
1863                                     !tc_act_in_hw(p))
1864                                         tcf_reoffload_del_notify(net, p);
1865                         }
1866                         mutex_unlock(&idrinfo->lock);
1867                 }
1868         }
1869         mutex_unlock(&act_id_mutex);
1870         up_read(&net_rwsem);
1871
1872         return 0;
1873 }
1874
1875 static int
1876 tcf_del_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[],
1877                u32 portid, size_t attr_size, struct netlink_ext_ack *extack)
1878 {
1879         int ret;
1880         struct sk_buff *skb;
1881
1882         skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1883                         GFP_KERNEL);
1884         if (!skb)
1885                 return -ENOBUFS;
1886
1887         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, RTM_DELACTION,
1888                          0, 2) <= 0) {
1889                 NL_SET_ERR_MSG(extack, "Failed to fill netlink TC action attributes");
1890                 kfree_skb(skb);
1891                 return -EINVAL;
1892         }
1893
1894         /* now do the delete */
1895         ret = tcf_action_delete(net, actions);
1896         if (ret < 0) {
1897                 NL_SET_ERR_MSG(extack, "Failed to delete TC action");
1898                 kfree_skb(skb);
1899                 return ret;
1900         }
1901
1902         ret = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1903                              n->nlmsg_flags & NLM_F_ECHO);
1904         return ret;
1905 }
1906
1907 static int
1908 tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
1909               u32 portid, int event, struct netlink_ext_ack *extack)
1910 {
1911         int i, ret;
1912         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1913         struct tc_action *act;
1914         size_t attr_size = 0;
1915         struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
1916
1917         ret = nla_parse_nested_deprecated(tb, TCA_ACT_MAX_PRIO, nla, NULL,
1918                                           extack);
1919         if (ret < 0)
1920                 return ret;
1921
1922         if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) {
1923                 if (tb[1])
1924                         return tca_action_flush(net, tb[1], n, portid, extack);
1925
1926                 NL_SET_ERR_MSG(extack, "Invalid netlink attributes while flushing TC action");
1927                 return -EINVAL;
1928         }
1929
1930         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1931                 act = tcf_action_get_1(net, tb[i], n, portid, extack);
1932                 if (IS_ERR(act)) {
1933                         ret = PTR_ERR(act);
1934                         goto err;
1935                 }
1936                 attr_size += tcf_action_fill_size(act);
1937                 actions[i - 1] = act;
1938         }
1939
1940         attr_size = tcf_action_full_attrs_size(attr_size);
1941
1942         if (event == RTM_GETACTION)
1943                 ret = tcf_get_notify(net, portid, n, actions, event, extack);
1944         else { /* delete */
1945                 ret = tcf_del_notify(net, n, actions, portid, attr_size, extack);
1946                 if (ret)
1947                         goto err;
1948                 return 0;
1949         }
1950 err:
1951         tcf_action_put_many(actions);
1952         return ret;
1953 }
1954
1955 static int
1956 tcf_add_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[],
1957                u32 portid, size_t attr_size, struct netlink_ext_ack *extack)
1958 {
1959         struct sk_buff *skb;
1960
1961         skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1962                         GFP_KERNEL);
1963         if (!skb)
1964                 return -ENOBUFS;
1965
1966         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, n->nlmsg_flags,
1967                          RTM_NEWACTION, 0, 0) <= 0) {
1968                 NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1969                 kfree_skb(skb);
1970                 return -EINVAL;
1971         }
1972
1973         return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1974                               n->nlmsg_flags & NLM_F_ECHO);
1975 }
1976
1977 static int tcf_action_add(struct net *net, struct nlattr *nla,
1978                           struct nlmsghdr *n, u32 portid, u32 flags,
1979                           struct netlink_ext_ack *extack)
1980 {
1981         size_t attr_size = 0;
1982         int loop, ret, i;
1983         struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
1984         int init_res[TCA_ACT_MAX_PRIO] = {};
1985
1986         for (loop = 0; loop < 10; loop++) {
1987                 ret = tcf_action_init(net, NULL, nla, NULL, actions, init_res,
1988                                       &attr_size, flags, 0, extack);
1989                 if (ret != -EAGAIN)
1990                         break;
1991         }
1992
1993         if (ret < 0)
1994                 return ret;
1995         ret = tcf_add_notify(net, n, actions, portid, attr_size, extack);
1996
1997         /* only put existing actions */
1998         for (i = 0; i < TCA_ACT_MAX_PRIO; i++)
1999                 if (init_res[i] == ACT_P_CREATED)
2000                         actions[i] = NULL;
2001         tcf_action_put_many(actions);
2002
2003         return ret;
2004 }
2005
2006 static const struct nla_policy tcaa_policy[TCA_ROOT_MAX + 1] = {
2007         [TCA_ROOT_FLAGS] = NLA_POLICY_BITFIELD32(TCA_ACT_FLAG_LARGE_DUMP_ON |
2008                                                  TCA_ACT_FLAG_TERSE_DUMP),
2009         [TCA_ROOT_TIME_DELTA]      = { .type = NLA_U32 },
2010 };
2011
2012 static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n,
2013                          struct netlink_ext_ack *extack)
2014 {
2015         struct net *net = sock_net(skb->sk);
2016         struct nlattr *tca[TCA_ROOT_MAX + 1];
2017         u32 portid = NETLINK_CB(skb).portid;
2018         u32 flags = 0;
2019         int ret = 0;
2020
2021         if ((n->nlmsg_type != RTM_GETACTION) &&
2022             !netlink_capable(skb, CAP_NET_ADMIN))
2023                 return -EPERM;
2024
2025         ret = nlmsg_parse_deprecated(n, sizeof(struct tcamsg), tca,
2026                                      TCA_ROOT_MAX, NULL, extack);
2027         if (ret < 0)
2028                 return ret;
2029
2030         if (tca[TCA_ACT_TAB] == NULL) {
2031                 NL_SET_ERR_MSG(extack, "Netlink action attributes missing");
2032                 return -EINVAL;
2033         }
2034
2035         /* n->nlmsg_flags & NLM_F_CREATE */
2036         switch (n->nlmsg_type) {
2037         case RTM_NEWACTION:
2038                 /* we are going to assume all other flags
2039                  * imply create only if it doesn't exist
2040                  * Note that CREATE | EXCL implies that
2041                  * but since we want avoid ambiguity (eg when flags
2042                  * is zero) then just set this
2043                  */
2044                 if (n->nlmsg_flags & NLM_F_REPLACE)
2045                         flags = TCA_ACT_FLAGS_REPLACE;
2046                 ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, portid, flags,
2047                                      extack);
2048                 break;
2049         case RTM_DELACTION:
2050                 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
2051                                     portid, RTM_DELACTION, extack);
2052                 break;
2053         case RTM_GETACTION:
2054                 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
2055                                     portid, RTM_GETACTION, extack);
2056                 break;
2057         default:
2058                 BUG();
2059         }
2060
2061         return ret;
2062 }
2063
2064 static struct nlattr *find_dump_kind(struct nlattr **nla)
2065 {
2066         struct nlattr *tb1, *tb2[TCA_ACT_MAX + 1];
2067         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
2068         struct nlattr *kind;
2069
2070         tb1 = nla[TCA_ACT_TAB];
2071         if (tb1 == NULL)
2072                 return NULL;
2073
2074         if (nla_parse_deprecated(tb, TCA_ACT_MAX_PRIO, nla_data(tb1), NLMSG_ALIGN(nla_len(tb1)), NULL, NULL) < 0)
2075                 return NULL;
2076
2077         if (tb[1] == NULL)
2078                 return NULL;
2079         if (nla_parse_nested_deprecated(tb2, TCA_ACT_MAX, tb[1], tcf_action_policy, NULL) < 0)
2080                 return NULL;
2081         kind = tb2[TCA_ACT_KIND];
2082
2083         return kind;
2084 }
2085
2086 static int tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
2087 {
2088         struct net *net = sock_net(skb->sk);
2089         struct nlmsghdr *nlh;
2090         unsigned char *b = skb_tail_pointer(skb);
2091         struct nlattr *nest;
2092         struct tc_action_ops *a_o;
2093         int ret = 0;
2094         struct tcamsg *t = (struct tcamsg *) nlmsg_data(cb->nlh);
2095         struct nlattr *tb[TCA_ROOT_MAX + 1];
2096         struct nlattr *count_attr = NULL;
2097         unsigned long jiffy_since = 0;
2098         struct nlattr *kind = NULL;
2099         struct nla_bitfield32 bf;
2100         u32 msecs_since = 0;
2101         u32 act_count = 0;
2102
2103         ret = nlmsg_parse_deprecated(cb->nlh, sizeof(struct tcamsg), tb,
2104                                      TCA_ROOT_MAX, tcaa_policy, cb->extack);
2105         if (ret < 0)
2106                 return ret;
2107
2108         kind = find_dump_kind(tb);
2109         if (kind == NULL) {
2110                 pr_info("tc_dump_action: action bad kind\n");
2111                 return 0;
2112         }
2113
2114         a_o = tc_lookup_action(kind);
2115         if (a_o == NULL)
2116                 return 0;
2117
2118         cb->args[2] = 0;
2119         if (tb[TCA_ROOT_FLAGS]) {
2120                 bf = nla_get_bitfield32(tb[TCA_ROOT_FLAGS]);
2121                 cb->args[2] = bf.value;
2122         }
2123
2124         if (tb[TCA_ROOT_TIME_DELTA]) {
2125                 msecs_since = nla_get_u32(tb[TCA_ROOT_TIME_DELTA]);
2126         }
2127
2128         nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
2129                         cb->nlh->nlmsg_type, sizeof(*t), 0);
2130         if (!nlh)
2131                 goto out_module_put;
2132
2133         if (msecs_since)
2134                 jiffy_since = jiffies - msecs_to_jiffies(msecs_since);
2135
2136         t = nlmsg_data(nlh);
2137         t->tca_family = AF_UNSPEC;
2138         t->tca__pad1 = 0;
2139         t->tca__pad2 = 0;
2140         cb->args[3] = jiffy_since;
2141         count_attr = nla_reserve(skb, TCA_ROOT_COUNT, sizeof(u32));
2142         if (!count_attr)
2143                 goto out_module_put;
2144
2145         nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
2146         if (nest == NULL)
2147                 goto out_module_put;
2148
2149         ret = __tcf_generic_walker(net, skb, cb, RTM_GETACTION, a_o, NULL);
2150         if (ret < 0)
2151                 goto out_module_put;
2152
2153         if (ret > 0) {
2154                 nla_nest_end(skb, nest);
2155                 ret = skb->len;
2156                 act_count = cb->args[1];
2157                 memcpy(nla_data(count_attr), &act_count, sizeof(u32));
2158                 cb->args[1] = 0;
2159         } else
2160                 nlmsg_trim(skb, b);
2161
2162         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
2163         if (NETLINK_CB(cb->skb).portid && ret)
2164                 nlh->nlmsg_flags |= NLM_F_MULTI;
2165         module_put(a_o->owner);
2166         return skb->len;
2167
2168 out_module_put:
2169         module_put(a_o->owner);
2170         nlmsg_trim(skb, b);
2171         return skb->len;
2172 }
2173
2174 static int __init tc_action_init(void)
2175 {
2176         rtnl_register(PF_UNSPEC, RTM_NEWACTION, tc_ctl_action, NULL, 0);
2177         rtnl_register(PF_UNSPEC, RTM_DELACTION, tc_ctl_action, NULL, 0);
2178         rtnl_register(PF_UNSPEC, RTM_GETACTION, tc_ctl_action, tc_dump_action,
2179                       0);
2180
2181         return 0;
2182 }
2183
2184 subsys_initcall(tc_action_init);