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 {
 593         struct nlattr *nest;
 594         int n_i = 0;
 595         int ret = -EINVAL;
 596         struct idr *idr = &idrinfo->action_idr;
 597         struct tc_action *p;
 598         unsigned long id = 1;
 599         unsigned long tmp;
 600
 601         nest = nla_nest_start_noflag(skb, 0);
 602         if (nest == NULL)
 603                 goto nla_put_failure;
 604         if (nla_put_string(skb, TCA_KIND, ops->kind))
 605                 goto nla_put_failure;
 606
 607         mutex_lock(&idrinfo->lock);
 608         idr_for_each_entry_ul(idr, p, tmp, id) {
 609                 if (IS_ERR(p))
 610                         continue;
 611                 ret = tcf_idr_release_unsafe(p);
 612                 if (ret == ACT_P_DELETED) {
 613                         module_put(ops->owner);
 614                         n_i++;
 615                 } else if (ret < 0) {
 616                         mutex_unlock(&idrinfo->lock);
 617                         goto nla_put_failure;
 618                 }
 619         }
 620         mutex_unlock(&idrinfo->lock);
 621
 622         ret = nla_put_u32(skb, TCA_FCNT, n_i);
 623         if (ret)
 624                 goto nla_put_failure;
 625         nla_nest_end(skb, nest);
 626
 627         return n_i;
 628 nla_put_failure:
 629         nla_nest_cancel(skb, nest);
 630         return ret;
 631 }
 632
 633 int tcf_generic_walker(struct tc_action_net *tn, struct sk_buff *skb,
 634                        struct netlink_callback *cb, int type,
 635                        const struct tc_action_ops *ops,
 636                        struct netlink_ext_ack *extack)
 637 {
 638         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 639
 640         if (type == RTM_DELACTION) {
 641                 return tcf_del_walker(idrinfo, skb, ops);
 642         } else if (type == RTM_GETACTION) {
 643                 return tcf_dump_walker(idrinfo, skb, cb);
 644         } else {
 645                 WARN(1, "tcf_generic_walker: unknown command %d\n", type);
 646                 NL_SET_ERR_MSG(extack, "tcf_generic_walker: unknown command");
 647                 return -EINVAL;
 648         }
 649 }
 650 EXPORT_SYMBOL(tcf_generic_walker);
 651
 652 int tcf_idr_search(struct tc_action_net *tn, struct tc_action **a, u32 index)
 653 {
 654         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 655         struct tc_action *p;
 656
 657         mutex_lock(&idrinfo->lock);
 658         p = idr_find(&idrinfo->action_idr, index);
 659         if (IS_ERR(p))
 660                 p = NULL;
 661         else if (p)
 662                 refcount_inc(&p->tcfa_refcnt);
 663         mutex_unlock(&idrinfo->lock);
 664
 665         if (p) {
 666                 *a = p;
 667                 return true;
 668         }
 669         return false;
 670 }
 671 EXPORT_SYMBOL(tcf_idr_search);
 672
 673 static int tcf_idr_delete_index(struct tcf_idrinfo *idrinfo, u32 index)
 674 {
 675         struct tc_action *p;
 676         int ret = 0;
 677
 678         mutex_lock(&idrinfo->lock);
 679         p = idr_find(&idrinfo->action_idr, index);
 680         if (!p) {
 681                 mutex_unlock(&idrinfo->lock);
 682                 return -ENOENT;
 683         }
 684
 685         if (!atomic_read(&p->tcfa_bindcnt)) {
 686                 if (refcount_dec_and_test(&p->tcfa_refcnt)) {
 687                         struct module *owner = p->ops->owner;
 688
 689                         WARN_ON(p != idr_remove(&idrinfo->action_idr,
 690                                                 p->tcfa_index));
 691                         mutex_unlock(&idrinfo->lock);
 692
 693                         tcf_action_cleanup(p);
 694                         module_put(owner);
 695                         return 0;
 696                 }
 697                 ret = 0;
 698         } else {
 699                 ret = -EPERM;
 700         }
 701
 702         mutex_unlock(&idrinfo->lock);
 703         return ret;
 704 }
 705
 706 int tcf_idr_create(struct tc_action_net *tn, u32 index, struct nlattr *est,
 707                    struct tc_action **a, const struct tc_action_ops *ops,
 708                    int bind, bool cpustats, u32 flags)
 709 {
 710         struct tc_action *p = kzalloc(ops->size, GFP_KERNEL);
 711         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 712         int err = -ENOMEM;
 713
 714         if (unlikely(!p))
 715                 return -ENOMEM;
 716         refcount_set(&p->tcfa_refcnt, 1);
 717         if (bind)
 718                 atomic_set(&p->tcfa_bindcnt, 1);
 719
 720         if (cpustats) {
 721                 p->cpu_bstats = netdev_alloc_pcpu_stats(struct gnet_stats_basic_sync);
 722                 if (!p->cpu_bstats)
 723                         goto err1;
 724                 p->cpu_bstats_hw = netdev_alloc_pcpu_stats(struct gnet_stats_basic_sync);
 725                 if (!p->cpu_bstats_hw)
 726                         goto err2;
 727                 p->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
 728                 if (!p->cpu_qstats)
 729                         goto err3;
 730         }
 731         gnet_stats_basic_sync_init(&p->tcfa_bstats);
 732         gnet_stats_basic_sync_init(&p->tcfa_bstats_hw);
 733         spin_lock_init(&p->tcfa_lock);
 734         p->tcfa_index = index;
 735         p->tcfa_tm.install = jiffies;
 736         p->tcfa_tm.lastuse = jiffies;
 737         p->tcfa_tm.firstuse = 0;
 738         p->tcfa_flags = flags;
 739         if (est) {
 740                 err = gen_new_estimator(&p->tcfa_bstats, p->cpu_bstats,
 741                                         &p->tcfa_rate_est,
 742                                         &p->tcfa_lock, false, est);
 743                 if (err)
 744                         goto err4;
 745         }
 746
 747         p->idrinfo = idrinfo;
 748         __module_get(ops->owner);
 749         p->ops = ops;
 750         *a = p;
 751         return 0;
 752 err4:
 753         free_percpu(p->cpu_qstats);
 754 err3:
 755         free_percpu(p->cpu_bstats_hw);
 756 err2:
 757         free_percpu(p->cpu_bstats);
 758 err1:
 759         kfree(p);
 760         return err;
 761 }
 762 EXPORT_SYMBOL(tcf_idr_create);
 763
 764 int tcf_idr_create_from_flags(struct tc_action_net *tn, u32 index,
 765                               struct nlattr *est, struct tc_action **a,
 766                               const struct tc_action_ops *ops, int bind,
 767                               u32 flags)
 768 {
 769         /* Set cpustats according to actions flags. */
 770         return tcf_idr_create(tn, index, est, a, ops, bind,
 771                               !(flags & TCA_ACT_FLAGS_NO_PERCPU_STATS), flags);
 772 }
 773 EXPORT_SYMBOL(tcf_idr_create_from_flags);
 774
 775 /* Cleanup idr index that was allocated but not initialized. */
 776
 777 void tcf_idr_cleanup(struct tc_action_net *tn, u32 index)
 778 {
 779         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 780
 781         mutex_lock(&idrinfo->lock);
 782         /* Remove ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */
 783         WARN_ON(!IS_ERR(idr_remove(&idrinfo->action_idr, index)));
 784         mutex_unlock(&idrinfo->lock);
 785 }
 786 EXPORT_SYMBOL(tcf_idr_cleanup);
 787
 788 /* Check if action with specified index exists. If actions is found, increments
 789  * its reference and bind counters, and return 1. Otherwise insert temporary
 790  * error pointer (to prevent concurrent users from inserting actions with same
 791  * index) and return 0.
 792  */
 793
 794 int tcf_idr_check_alloc(struct tc_action_net *tn, u32 *index,
 795                         struct tc_action **a, int bind)
 796 {
 797         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 798         struct tc_action *p;
 799         int ret;
 800
 801 again:
 802         mutex_lock(&idrinfo->lock);
 803         if (*index) {
 804                 p = idr_find(&idrinfo->action_idr, *index);
 805                 if (IS_ERR(p)) {
 806                         /* This means that another process allocated
 807                          * index but did not assign the pointer yet.
 808                          */
 809                         mutex_unlock(&idrinfo->lock);
 810                         goto again;
 811                 }
 812
 813                 if (p) {
 814                         refcount_inc(&p->tcfa_refcnt);
 815                         if (bind)
 816                                 atomic_inc(&p->tcfa_bindcnt);
 817                         *a = p;
 818                         ret = 1;
 819                 } else {
 820                         *a = NULL;
 821                         ret = idr_alloc_u32(&idrinfo->action_idr, NULL, index,
 822                                             *index, GFP_KERNEL);
 823                         if (!ret)
 824                                 idr_replace(&idrinfo->action_idr,
 825                                             ERR_PTR(-EBUSY), *index);
 826                 }
 827         } else {
 828                 *index = 1;
 829                 *a = NULL;
 830                 ret = idr_alloc_u32(&idrinfo->action_idr, NULL, index,
 831                                     UINT_MAX, GFP_KERNEL);
 832                 if (!ret)
 833                         idr_replace(&idrinfo->action_idr, ERR_PTR(-EBUSY),
 834                                     *index);
 835         }
 836         mutex_unlock(&idrinfo->lock);
 837         return ret;
 838 }
 839 EXPORT_SYMBOL(tcf_idr_check_alloc);
 840
 841 void tcf_idrinfo_destroy(const struct tc_action_ops *ops,
 842                          struct tcf_idrinfo *idrinfo)
 843 {
 844         struct idr *idr = &idrinfo->action_idr;
 845         struct tc_action *p;
 846         int ret;
 847         unsigned long id = 1;
 848         unsigned long tmp;
 849
 850         idr_for_each_entry_ul(idr, p, tmp, id) {
 851                 ret = __tcf_idr_release(p, false, true);
 852                 if (ret == ACT_P_DELETED)
 853                         module_put(ops->owner);
 854                 else if (ret < 0)
 855                         return;
 856         }
 857         idr_destroy(&idrinfo->action_idr);
 858 }
 859 EXPORT_SYMBOL(tcf_idrinfo_destroy);
 860
 861 static LIST_HEAD(act_base);
 862 static DEFINE_RWLOCK(act_mod_lock);
 863 /* since act ops id is stored in pernet subsystem list,
 864  * then there is no way to walk through only all the action
 865  * subsystem, so we keep tc action pernet ops id for
 866  * reoffload to walk through.
 867  */
 868 static LIST_HEAD(act_pernet_id_list);
 869 static DEFINE_MUTEX(act_id_mutex);
 870 struct tc_act_pernet_id {
 871         struct list_head list;
 872         unsigned int id;
 873 };
 874
 875 static int tcf_pernet_add_id_list(unsigned int id)
 876 {
 877         struct tc_act_pernet_id *id_ptr;
 878         int ret = 0;
 879
 880         mutex_lock(&act_id_mutex);
 881         list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
 882                 if (id_ptr->id == id) {
 883                         ret = -EEXIST;
 884                         goto err_out;
 885                 }
 886         }
 887
 888         id_ptr = kzalloc(sizeof(*id_ptr), GFP_KERNEL);
 889         if (!id_ptr) {
 890                 ret = -ENOMEM;
 891                 goto err_out;
 892         }
 893         id_ptr->id = id;
 894
 895         list_add_tail(&id_ptr->list, &act_pernet_id_list);
 896
 897 err_out:
 898         mutex_unlock(&act_id_mutex);
 899         return ret;
 900 }
 901
 902 static void tcf_pernet_del_id_list(unsigned int id)
 903 {
 904         struct tc_act_pernet_id *id_ptr;
 905
 906         mutex_lock(&act_id_mutex);
 907         list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
 908                 if (id_ptr->id == id) {
 909                         list_del(&id_ptr->list);
 910                         kfree(id_ptr);
 911                         break;
 912                 }
 913         }
 914         mutex_unlock(&act_id_mutex);
 915 }
 916
 917 int tcf_register_action(struct tc_action_ops *act,
 918                         struct pernet_operations *ops)
 919 {
 920         struct tc_action_ops *a;
 921         int ret;
 922
 923         if (!act->act || !act->dump || !act->init || !act->walk || !act->lookup)
 924                 return -EINVAL;
 925
 926         /* We have to register pernet ops before making the action ops visible,
 927          * otherwise tcf_action_init_1() could get a partially initialized
 928          * netns.
 929          */
 930         ret = register_pernet_subsys(ops);
 931         if (ret)
 932                 return ret;
 933
 934         if (ops->id) {
 935                 ret = tcf_pernet_add_id_list(*ops->id);
 936                 if (ret)
 937                         goto err_id;
 938         }
 939
 940         write_lock(&act_mod_lock);
 941         list_for_each_entry(a, &act_base, head) {
 942                 if (act->id == a->id || (strcmp(act->kind, a->kind) == 0)) {
 943                         ret = -EEXIST;
 944                         goto err_out;
 945                 }
 946         }
 947         list_add_tail(&act->head, &act_base);
 948         write_unlock(&act_mod_lock);
 949
 950         return 0;
 951
 952 err_out:
 953         write_unlock(&act_mod_lock);
 954         if (ops->id)
 955                 tcf_pernet_del_id_list(*ops->id);
 956 err_id:
 957         unregister_pernet_subsys(ops);
 958         return ret;
 959 }
 960 EXPORT_SYMBOL(tcf_register_action);
 961
 962 int tcf_unregister_action(struct tc_action_ops *act,
 963                           struct pernet_operations *ops)
 964 {
 965         struct tc_action_ops *a;
 966         int err = -ENOENT;
 967
 968         write_lock(&act_mod_lock);
 969         list_for_each_entry(a, &act_base, head) {
 970                 if (a == act) {
 971                         list_del(&act->head);
 972                         err = 0;
 973                         break;
 974                 }
 975         }
 976         write_unlock(&act_mod_lock);
 977         if (!err) {
 978                 unregister_pernet_subsys(ops);
 979                 if (ops->id)
 980                         tcf_pernet_del_id_list(*ops->id);
 981         }
 982         return err;
 983 }
 984 EXPORT_SYMBOL(tcf_unregister_action);
 985
 986 /* lookup by name */
 987 static struct tc_action_ops *tc_lookup_action_n(char *kind)
 988 {
 989         struct tc_action_ops *a, *res = NULL;
 990
 991         if (kind) {
 992                 read_lock(&act_mod_lock);
 993                 list_for_each_entry(a, &act_base, head) {
 994                         if (strcmp(kind, a->kind) == 0) {
 995                                 if (try_module_get(a->owner))
 996                                         res = a;
 997                                 break;
 998                         }
 999                 }
1000                 read_unlock(&act_mod_lock);
1001         }
1002         return res;
1003 }
1004
1005 /* lookup by nlattr */
1006 static struct tc_action_ops *tc_lookup_action(struct nlattr *kind)
1007 {
1008         struct tc_action_ops *a, *res = NULL;
1009
1010         if (kind) {
1011                 read_lock(&act_mod_lock);
1012                 list_for_each_entry(a, &act_base, head) {
1013                         if (nla_strcmp(kind, a->kind) == 0) {
1014                                 if (try_module_get(a->owner))
1015                                         res = a;
1016                                 break;
1017                         }
1018                 }
1019                 read_unlock(&act_mod_lock);
1020         }
1021         return res;
1022 }
1023
1024 /*TCA_ACT_MAX_PRIO is 32, there count up to 32 */
1025 #define TCA_ACT_MAX_PRIO_MASK 0x1FF
1026 int tcf_action_exec(struct sk_buff *skb, struct tc_action **actions,
1027                     int nr_actions, struct tcf_result *res)
1028 {
1029         u32 jmp_prgcnt = 0;
1030         u32 jmp_ttl = TCA_ACT_MAX_PRIO; /*matches actions per filter */
1031         int i;
1032         int ret = TC_ACT_OK;
1033
1034         if (skb_skip_tc_classify(skb))
1035                 return TC_ACT_OK;
1036
1037 restart_act_graph:
1038         for (i = 0; i < nr_actions; i++) {
1039                 const struct tc_action *a = actions[i];
1040                 int repeat_ttl;
1041
1042                 if (jmp_prgcnt > 0) {
1043                         jmp_prgcnt -= 1;
1044                         continue;
1045                 }
1046
1047                 if (tc_act_skip_sw(a->tcfa_flags))
1048                         continue;
1049
1050                 repeat_ttl = 32;
1051 repeat:
1052                 ret = a->ops->act(skb, a, res);
1053                 if (unlikely(ret == TC_ACT_REPEAT)) {
1054                         if (--repeat_ttl != 0)
1055                                 goto repeat;
1056                         /* suspicious opcode, stop pipeline */
1057                         net_warn_ratelimited("TC_ACT_REPEAT abuse ?\n");
1058                         return TC_ACT_OK;
1059                 }
1060                 if (TC_ACT_EXT_CMP(ret, TC_ACT_JUMP)) {
1061                         jmp_prgcnt = ret & TCA_ACT_MAX_PRIO_MASK;
1062                         if (!jmp_prgcnt || (jmp_prgcnt > nr_actions)) {
1063                                 /* faulty opcode, stop pipeline */
1064                                 return TC_ACT_OK;
1065                         } else {
1066                                 jmp_ttl -= 1;
1067                                 if (jmp_ttl > 0)
1068                                         goto restart_act_graph;
1069                                 else /* faulty graph, stop pipeline */
1070                                         return TC_ACT_OK;
1071                         }
1072                 } else if (TC_ACT_EXT_CMP(ret, TC_ACT_GOTO_CHAIN)) {
1073                         if (unlikely(!rcu_access_pointer(a->goto_chain))) {
1074                                 net_warn_ratelimited("can't go to NULL chain!\n");
1075                                 return TC_ACT_SHOT;
1076                         }
1077                         tcf_action_goto_chain_exec(a, res);
1078                 }
1079
1080                 if (ret != TC_ACT_PIPE)
1081                         break;
1082         }
1083
1084         return ret;
1085 }
1086 EXPORT_SYMBOL(tcf_action_exec);
1087
1088 int tcf_action_destroy(struct tc_action *actions[], int bind)
1089 {
1090         const struct tc_action_ops *ops;
1091         struct tc_action *a;
1092         int ret = 0, i;
1093
1094         for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
1095                 a = actions[i];
1096                 actions[i] = NULL;
1097                 ops = a->ops;
1098                 ret = __tcf_idr_release(a, bind, true);
1099                 if (ret == ACT_P_DELETED)
1100                         module_put(ops->owner);
1101                 else if (ret < 0)
1102                         return ret;
1103         }
1104         return ret;
1105 }
1106
1107 static int tcf_action_put(struct tc_action *p)
1108 {
1109         return __tcf_action_put(p, false);
1110 }
1111
1112 /* Put all actions in this array, skip those NULL's. */
1113 static void tcf_action_put_many(struct tc_action *actions[])
1114 {
1115         int i;
1116
1117         for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
1118                 struct tc_action *a = actions[i];
1119                 const struct tc_action_ops *ops;
1120
1121                 if (!a)
1122                         continue;
1123                 ops = a->ops;
1124                 if (tcf_action_put(a))
1125                         module_put(ops->owner);
1126         }
1127 }
1128
1129 int
1130 tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
1131 {
1132         return a->ops->dump(skb, a, bind, ref);
1133 }
1134
1135 int
1136 tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
1137 {
1138         int err = -EINVAL;
1139         unsigned char *b = skb_tail_pointer(skb);
1140         struct nlattr *nest;
1141         u32 flags;
1142
1143         if (tcf_action_dump_terse(skb, a, false))
1144                 goto nla_put_failure;
1145
1146         if (a->hw_stats != TCA_ACT_HW_STATS_ANY &&
1147             nla_put_bitfield32(skb, TCA_ACT_HW_STATS,
1148                                a->hw_stats, TCA_ACT_HW_STATS_ANY))
1149                 goto nla_put_failure;
1150
1151         if (a->used_hw_stats_valid &&
1152             nla_put_bitfield32(skb, TCA_ACT_USED_HW_STATS,
1153                                a->used_hw_stats, TCA_ACT_HW_STATS_ANY))
1154                 goto nla_put_failure;
1155
1156         flags = a->tcfa_flags & TCA_ACT_FLAGS_USER_MASK;
1157         if (flags &&
1158             nla_put_bitfield32(skb, TCA_ACT_FLAGS,
1159                                flags, flags))
1160                 goto nla_put_failure;
1161
1162         if (nla_put_u32(skb, TCA_ACT_IN_HW_COUNT, a->in_hw_count))
1163                 goto nla_put_failure;
1164
1165         nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
1166         if (nest == NULL)
1167                 goto nla_put_failure;
1168         err = tcf_action_dump_old(skb, a, bind, ref);
1169         if (err > 0) {
1170                 nla_nest_end(skb, nest);
1171                 return err;
1172         }
1173
1174 nla_put_failure:
1175         nlmsg_trim(skb, b);
1176         return -1;
1177 }
1178 EXPORT_SYMBOL(tcf_action_dump_1);
1179
1180 int tcf_action_dump(struct sk_buff *skb, struct tc_action *actions[],
1181                     int bind, int ref, bool terse)
1182 {
1183         struct tc_action *a;
1184         int err = -EINVAL, i;
1185         struct nlattr *nest;
1186
1187         for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
1188                 a = actions[i];
1189                 nest = nla_nest_start_noflag(skb, i + 1);
1190                 if (nest == NULL)
1191                         goto nla_put_failure;
1192                 err = terse ? tcf_action_dump_terse(skb, a, false) :
1193                         tcf_action_dump_1(skb, a, bind, ref);
1194                 if (err < 0)
1195                         goto errout;
1196                 nla_nest_end(skb, nest);
1197         }
1198
1199         return 0;
1200
1201 nla_put_failure:
1202         err = -EINVAL;
1203 errout:
1204         nla_nest_cancel(skb, nest);
1205         return err;
1206 }
1207
1208 static struct tc_cookie *nla_memdup_cookie(struct nlattr **tb)
1209 {
1210         struct tc_cookie *c = kzalloc(sizeof(*c), GFP_KERNEL);
1211         if (!c)
1212                 return NULL;
1213
1214         c->data = nla_memdup(tb[TCA_ACT_COOKIE], GFP_KERNEL);
1215         if (!c->data) {
1216                 kfree(c);
1217                 return NULL;
1218         }
1219         c->len = nla_len(tb[TCA_ACT_COOKIE]);
1220
1221         return c;
1222 }
1223
1224 static u8 tcf_action_hw_stats_get(struct nlattr *hw_stats_attr)
1225 {
1226         struct nla_bitfield32 hw_stats_bf;
1227
1228         /* If the user did not pass the attr, that means he does
1229          * not care about the type. Return "any" in that case
1230          * which is setting on all supported types.
1231          */
1232         if (!hw_stats_attr)
1233                 return TCA_ACT_HW_STATS_ANY;
1234         hw_stats_bf = nla_get_bitfield32(hw_stats_attr);
1235         return hw_stats_bf.value;
1236 }
1237
1238 static const struct nla_policy tcf_action_policy[TCA_ACT_MAX + 1] = {
1239         [TCA_ACT_KIND]          = { .type = NLA_STRING },
1240         [TCA_ACT_INDEX]         = { .type = NLA_U32 },
1241         [TCA_ACT_COOKIE]        = { .type = NLA_BINARY,
1242                                     .len = TC_COOKIE_MAX_SIZE },
1243         [TCA_ACT_OPTIONS]       = { .type = NLA_NESTED },
1244         [TCA_ACT_FLAGS]         = NLA_POLICY_BITFIELD32(TCA_ACT_FLAGS_NO_PERCPU_STATS |
1245                                                         TCA_ACT_FLAGS_SKIP_HW |
1246                                                         TCA_ACT_FLAGS_SKIP_SW),
1247         [TCA_ACT_HW_STATS]      = NLA_POLICY_BITFIELD32(TCA_ACT_HW_STATS_ANY),
1248 };
1249
1250 void tcf_idr_insert_many(struct tc_action *actions[])
1251 {
1252         int i;
1253
1254         for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
1255                 struct tc_action *a = actions[i];
1256                 struct tcf_idrinfo *idrinfo;
1257
1258                 if (!a)
1259                         continue;
1260                 idrinfo = a->idrinfo;
1261                 mutex_lock(&idrinfo->lock);
1262                 /* Replace ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc if
1263                  * it is just created, otherwise this is just a nop.
1264                  */
1265                 idr_replace(&idrinfo->action_idr, a, a->tcfa_index);
1266                 mutex_unlock(&idrinfo->lock);
1267         }
1268 }
1269
1270 struct tc_action_ops *tc_action_load_ops(struct nlattr *nla, bool police,
1271                                          bool rtnl_held,
1272                                          struct netlink_ext_ack *extack)
1273 {
1274         struct nlattr *tb[TCA_ACT_MAX + 1];
1275         struct tc_action_ops *a_o;
1276         char act_name[IFNAMSIZ];
1277         struct nlattr *kind;
1278         int err;
1279
1280         if (!police) {
1281                 err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1282                                                   tcf_action_policy, extack);
1283                 if (err < 0)
1284                         return ERR_PTR(err);
1285                 err = -EINVAL;
1286                 kind = tb[TCA_ACT_KIND];
1287                 if (!kind) {
1288                         NL_SET_ERR_MSG(extack, "TC action kind must be specified");
1289                         return ERR_PTR(err);
1290                 }
1291                 if (nla_strscpy(act_name, kind, IFNAMSIZ) < 0) {
1292                         NL_SET_ERR_MSG(extack, "TC action name too long");
1293                         return ERR_PTR(err);
1294                 }
1295         } else {
1296                 if (strlcpy(act_name, "police", IFNAMSIZ) >= IFNAMSIZ) {
1297                         NL_SET_ERR_MSG(extack, "TC action name too long");
1298                         return ERR_PTR(-EINVAL);
1299                 }
1300         }
1301
1302         a_o = tc_lookup_action_n(act_name);
1303         if (a_o == NULL) {
1304 #ifdef CONFIG_MODULES
1305                 if (rtnl_held)
1306                         rtnl_unlock();
1307                 request_module("act_%s", act_name);
1308                 if (rtnl_held)
1309                         rtnl_lock();
1310
1311                 a_o = tc_lookup_action_n(act_name);
1312
1313                 /* We dropped the RTNL semaphore in order to
1314                  * perform the module load.  So, even if we
1315                  * succeeded in loading the module we have to
1316                  * tell the caller to replay the request.  We
1317                  * indicate this using -EAGAIN.
1318                  */
1319                 if (a_o != NULL) {
1320                         module_put(a_o->owner);
1321                         return ERR_PTR(-EAGAIN);
1322                 }
1323 #endif
1324                 NL_SET_ERR_MSG(extack, "Failed to load TC action module");
1325                 return ERR_PTR(-ENOENT);
1326         }
1327
1328         return a_o;
1329 }
1330
1331 struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
1332                                     struct nlattr *nla, struct nlattr *est,
1333                                     struct tc_action_ops *a_o, int *init_res,
1334                                     u32 flags, struct netlink_ext_ack *extack)
1335 {
1336         bool police = flags & TCA_ACT_FLAGS_POLICE;
1337         struct nla_bitfield32 userflags = { 0, 0 };
1338         u8 hw_stats = TCA_ACT_HW_STATS_ANY;
1339         struct nlattr *tb[TCA_ACT_MAX + 1];
1340         struct tc_cookie *cookie = NULL;
1341         struct tc_action *a;
1342         int err;
1343
1344         /* backward compatibility for policer */
1345         if (!police) {
1346                 err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1347                                                   tcf_action_policy, extack);
1348                 if (err < 0)
1349                         return ERR_PTR(err);
1350                 if (tb[TCA_ACT_COOKIE]) {
1351                         cookie = nla_memdup_cookie(tb);
1352                         if (!cookie) {
1353                                 NL_SET_ERR_MSG(extack, "No memory to generate TC cookie");
1354                                 err = -ENOMEM;
1355                                 goto err_out;
1356                         }
1357                 }
1358                 hw_stats = tcf_action_hw_stats_get(tb[TCA_ACT_HW_STATS]);
1359                 if (tb[TCA_ACT_FLAGS]) {
1360                         userflags = nla_get_bitfield32(tb[TCA_ACT_FLAGS]);
1361                         if (!tc_act_flags_valid(userflags.value)) {
1362                                 err = -EINVAL;
1363                                 goto err_out;
1364                         }
1365                 }
1366
1367                 err = a_o->init(net, tb[TCA_ACT_OPTIONS], est, &a, tp,
1368                                 userflags.value | flags, extack);
1369         } else {
1370                 err = a_o->init(net, nla, est, &a, tp, userflags.value | flags,
1371                                 extack);
1372         }
1373         if (err < 0)
1374                 goto err_out;
1375         *init_res = err;
1376
1377         if (!police && tb[TCA_ACT_COOKIE])
1378                 tcf_set_action_cookie(&a->act_cookie, cookie);
1379
1380         if (!police)
1381                 a->hw_stats = hw_stats;
1382
1383         return a;
1384
1385 err_out:
1386         if (cookie) {
1387                 kfree(cookie->data);
1388                 kfree(cookie);
1389         }
1390         return ERR_PTR(err);
1391 }
1392
1393 static bool tc_act_bind(u32 flags)
1394 {
1395         return !!(flags & TCA_ACT_FLAGS_BIND);
1396 }
1397
1398 /* Returns numbers of initialized actions or negative error. */
1399
1400 int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla,
1401                     struct nlattr *est, struct tc_action *actions[],
1402                     int init_res[], size_t *attr_size,
1403                     u32 flags, u32 fl_flags,
1404                     struct netlink_ext_ack *extack)
1405 {
1406         struct tc_action_ops *ops[TCA_ACT_MAX_PRIO] = {};
1407         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1408         struct tc_action *act;
1409         size_t sz = 0;
1410         int err;
1411         int i;
1412
1413         err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX_PRIO, nla, NULL,
1414                                           extack);
1415         if (err < 0)
1416                 return err;
1417
1418         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1419                 struct tc_action_ops *a_o;
1420
1421                 a_o = tc_action_load_ops(tb[i], flags & TCA_ACT_FLAGS_POLICE,
1422                                          !(flags & TCA_ACT_FLAGS_NO_RTNL),
1423                                          extack);
1424                 if (IS_ERR(a_o)) {
1425                         err = PTR_ERR(a_o);
1426                         goto err_mod;
1427                 }
1428                 ops[i - 1] = a_o;
1429         }
1430
1431         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1432                 act = tcf_action_init_1(net, tp, tb[i], est, ops[i - 1],
1433                                         &init_res[i - 1], flags, extack);
1434                 if (IS_ERR(act)) {
1435                         err = PTR_ERR(act);
1436                         goto err;
1437                 }
1438                 sz += tcf_action_fill_size(act);
1439                 /* Start from index 0 */
1440                 actions[i - 1] = act;
1441                 if (tc_act_bind(flags)) {
1442                         bool skip_sw = tc_skip_sw(fl_flags);
1443                         bool skip_hw = tc_skip_hw(fl_flags);
1444
1445                         if (tc_act_bind(act->tcfa_flags))
1446                                 continue;
1447                         if (skip_sw != tc_act_skip_sw(act->tcfa_flags) ||
1448                             skip_hw != tc_act_skip_hw(act->tcfa_flags)) {
1449                                 NL_SET_ERR_MSG(extack,
1450                                                "Mismatch between action and filter offload flags");
1451                                 err = -EINVAL;
1452                                 goto err;
1453                         }
1454                 } else {
1455                         err = tcf_action_offload_add(act, extack);
1456                         if (tc_act_skip_sw(act->tcfa_flags) && err)
1457                                 goto err;
1458                 }
1459         }
1460
1461         /* We have to commit them all together, because if any error happened in
1462          * between, we could not handle the failure gracefully.
1463          */
1464         tcf_idr_insert_many(actions);
1465
1466         *attr_size = tcf_action_full_attrs_size(sz);
1467         err = i - 1;
1468         goto err_mod;
1469
1470 err:
1471         tcf_action_destroy(actions, flags & TCA_ACT_FLAGS_BIND);
1472 err_mod:
1473         for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
1474                 if (ops[i])
1475                         module_put(ops[i]->owner);
1476         }
1477         return err;
1478 }
1479
1480 void tcf_action_update_stats(struct tc_action *a, u64 bytes, u64 packets,
1481                              u64 drops, bool hw)
1482 {
1483         if (a->cpu_bstats) {
1484                 _bstats_update(this_cpu_ptr(a->cpu_bstats), bytes, packets);
1485
1486                 this_cpu_ptr(a->cpu_qstats)->drops += drops;
1487
1488                 if (hw)
1489                         _bstats_update(this_cpu_ptr(a->cpu_bstats_hw),
1490                                        bytes, packets);
1491                 return;
1492         }
1493
1494         _bstats_update(&a->tcfa_bstats, bytes, packets);
1495         a->tcfa_qstats.drops += drops;
1496         if (hw)
1497                 _bstats_update(&a->tcfa_bstats_hw, bytes, packets);
1498 }
1499 EXPORT_SYMBOL(tcf_action_update_stats);
1500
1501 int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *p,
1502                           int compat_mode)
1503 {
1504         int err = 0;
1505         struct gnet_dump d;
1506
1507         if (p == NULL)
1508                 goto errout;
1509
1510         /* update hw stats for this action */
1511         tcf_action_update_hw_stats(p);
1512
1513         /* compat_mode being true specifies a call that is supposed
1514          * to add additional backward compatibility statistic TLVs.
1515          */
1516         if (compat_mode) {
1517                 if (p->type == TCA_OLD_COMPAT)
1518                         err = gnet_stats_start_copy_compat(skb, 0,
1519                                                            TCA_STATS,
1520                                                            TCA_XSTATS,
1521                                                            &p->tcfa_lock, &d,
1522                                                            TCA_PAD);
1523                 else
1524                         return 0;
1525         } else
1526                 err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
1527                                             &p->tcfa_lock, &d, TCA_ACT_PAD);
1528
1529         if (err < 0)
1530                 goto errout;
1531
1532         if (gnet_stats_copy_basic(&d, p->cpu_bstats,
1533                                   &p->tcfa_bstats, false) < 0 ||
1534             gnet_stats_copy_basic_hw(&d, p->cpu_bstats_hw,
1535                                      &p->tcfa_bstats_hw, false) < 0 ||
1536             gnet_stats_copy_rate_est(&d, &p->tcfa_rate_est) < 0 ||
1537             gnet_stats_copy_queue(&d, p->cpu_qstats,
1538                                   &p->tcfa_qstats,
1539                                   p->tcfa_qstats.qlen) < 0)
1540                 goto errout;
1541
1542         if (gnet_stats_finish_copy(&d) < 0)
1543                 goto errout;
1544
1545         return 0;
1546
1547 errout:
1548         return -1;
1549 }
1550
1551 static int tca_get_fill(struct sk_buff *skb, struct tc_action *actions[],
1552                         u32 portid, u32 seq, u16 flags, int event, int bind,
1553                         int ref)
1554 {
1555         struct tcamsg *t;
1556         struct nlmsghdr *nlh;
1557         unsigned char *b = skb_tail_pointer(skb);
1558         struct nlattr *nest;
1559
1560         nlh = nlmsg_put(skb, portid, seq, event, sizeof(*t), flags);
1561         if (!nlh)
1562                 goto out_nlmsg_trim;
1563         t = nlmsg_data(nlh);
1564         t->tca_family = AF_UNSPEC;
1565         t->tca__pad1 = 0;
1566         t->tca__pad2 = 0;
1567
1568         nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
1569         if (!nest)
1570                 goto out_nlmsg_trim;
1571
1572         if (tcf_action_dump(skb, actions, bind, ref, false) < 0)
1573                 goto out_nlmsg_trim;
1574
1575         nla_nest_end(skb, nest);
1576
1577         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1578         return skb->len;
1579
1580 out_nlmsg_trim:
1581         nlmsg_trim(skb, b);
1582         return -1;
1583 }
1584
1585 static int
1586 tcf_get_notify(struct net *net, u32 portid, struct nlmsghdr *n,
1587                struct tc_action *actions[], int event,
1588                struct netlink_ext_ack *extack)
1589 {
1590         struct sk_buff *skb;
1591
1592         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1593         if (!skb)
1594                 return -ENOBUFS;
1595         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, event,
1596                          0, 1) <= 0) {
1597                 NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1598                 kfree_skb(skb);
1599                 return -EINVAL;
1600         }
1601
1602         return rtnl_unicast(skb, net, portid);
1603 }
1604
1605 static struct tc_action *tcf_action_get_1(struct net *net, struct nlattr *nla,
1606                                           struct nlmsghdr *n, u32 portid,
1607                                           struct netlink_ext_ack *extack)
1608 {
1609         struct nlattr *tb[TCA_ACT_MAX + 1];
1610         const struct tc_action_ops *ops;
1611         struct tc_action *a;
1612         int index;
1613         int err;
1614
1615         err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1616                                           tcf_action_policy, extack);
1617         if (err < 0)
1618                 goto err_out;
1619
1620         err = -EINVAL;
1621         if (tb[TCA_ACT_INDEX] == NULL ||
1622             nla_len(tb[TCA_ACT_INDEX]) < sizeof(index)) {
1623                 NL_SET_ERR_MSG(extack, "Invalid TC action index value");
1624                 goto err_out;
1625         }
1626         index = nla_get_u32(tb[TCA_ACT_INDEX]);
1627
1628         err = -EINVAL;
1629         ops = tc_lookup_action(tb[TCA_ACT_KIND]);
1630         if (!ops) { /* could happen in batch of actions */
1631                 NL_SET_ERR_MSG(extack, "Specified TC action kind not found");
1632                 goto err_out;
1633         }
1634         err = -ENOENT;
1635         if (ops->lookup(net, &a, index) == 0) {
1636                 NL_SET_ERR_MSG(extack, "TC action with specified index not found");
1637                 goto err_mod;
1638         }
1639
1640         module_put(ops->owner);
1641         return a;
1642
1643 err_mod:
1644         module_put(ops->owner);
1645 err_out:
1646         return ERR_PTR(err);
1647 }
1648
1649 static int tca_action_flush(struct net *net, struct nlattr *nla,
1650                             struct nlmsghdr *n, u32 portid,
1651                             struct netlink_ext_ack *extack)
1652 {
1653         struct sk_buff *skb;
1654         unsigned char *b;
1655         struct nlmsghdr *nlh;
1656         struct tcamsg *t;
1657         struct netlink_callback dcb;
1658         struct nlattr *nest;
1659         struct nlattr *tb[TCA_ACT_MAX + 1];
1660         const struct tc_action_ops *ops;
1661         struct nlattr *kind;
1662         int err = -ENOMEM;
1663
1664         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1665         if (!skb)
1666                 return err;
1667
1668         b = skb_tail_pointer(skb);
1669
1670         err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1671                                           tcf_action_policy, extack);
1672         if (err < 0)
1673                 goto err_out;
1674
1675         err = -EINVAL;
1676         kind = tb[TCA_ACT_KIND];
1677         ops = tc_lookup_action(kind);
1678         if (!ops) { /*some idjot trying to flush unknown action */
1679                 NL_SET_ERR_MSG(extack, "Cannot flush unknown TC action");
1680                 goto err_out;
1681         }
1682
1683         nlh = nlmsg_put(skb, portid, n->nlmsg_seq, RTM_DELACTION,
1684                         sizeof(*t), 0);
1685         if (!nlh) {
1686                 NL_SET_ERR_MSG(extack, "Failed to create TC action flush notification");
1687                 goto out_module_put;
1688         }
1689         t = nlmsg_data(nlh);
1690         t->tca_family = AF_UNSPEC;
1691         t->tca__pad1 = 0;
1692         t->tca__pad2 = 0;
1693
1694         nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
1695         if (!nest) {
1696                 NL_SET_ERR_MSG(extack, "Failed to add new netlink message");
1697                 goto out_module_put;
1698         }
1699
1700         err = ops->walk(net, skb, &dcb, RTM_DELACTION, ops, extack);
1701         if (err <= 0) {
1702                 nla_nest_cancel(skb, nest);
1703                 goto out_module_put;
1704         }
1705
1706         nla_nest_end(skb, nest);
1707
1708         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1709         nlh->nlmsg_flags |= NLM_F_ROOT;
1710         module_put(ops->owner);
1711         err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1712                              n->nlmsg_flags & NLM_F_ECHO);
1713         if (err < 0)
1714                 NL_SET_ERR_MSG(extack, "Failed to send TC action flush notification");
1715
1716         return err;
1717
1718 out_module_put:
1719         module_put(ops->owner);
1720 err_out:
1721         kfree_skb(skb);
1722         return err;
1723 }
1724
1725 static int tcf_action_delete(struct net *net, struct tc_action *actions[])
1726 {
1727         int i;
1728
1729         for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
1730                 struct tc_action *a = actions[i];
1731                 const struct tc_action_ops *ops = a->ops;
1732                 /* Actions can be deleted concurrently so we must save their
1733                  * type and id to search again after reference is released.
1734                  */
1735                 struct tcf_idrinfo *idrinfo = a->idrinfo;
1736                 u32 act_index = a->tcfa_index;
1737
1738                 actions[i] = NULL;
1739                 if (tcf_action_put(a)) {
1740                         /* last reference, action was deleted concurrently */
1741                         module_put(ops->owner);
1742                 } else  {
1743                         int ret;
1744
1745                         /* now do the delete */
1746                         ret = tcf_idr_delete_index(idrinfo, act_index);
1747                         if (ret < 0)
1748                                 return ret;
1749                 }
1750         }
1751         return 0;
1752 }
1753
1754 static int
1755 tcf_reoffload_del_notify(struct net *net, struct tc_action *action)
1756 {
1757         size_t attr_size = tcf_action_fill_size(action);
1758         struct tc_action *actions[TCA_ACT_MAX_PRIO] = {
1759                 [0] = action,
1760         };
1761         const struct tc_action_ops *ops = action->ops;
1762         struct sk_buff *skb;
1763         int ret;
1764
1765         skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1766                         GFP_KERNEL);
1767         if (!skb)
1768                 return -ENOBUFS;
1769
1770         if (tca_get_fill(skb, actions, 0, 0, 0, RTM_DELACTION, 0, 1) <= 0) {
1771                 kfree_skb(skb);
1772                 return -EINVAL;
1773         }
1774
1775         ret = tcf_idr_release_unsafe(action);
1776         if (ret == ACT_P_DELETED) {
1777                 module_put(ops->owner);
1778                 ret = rtnetlink_send(skb, net, 0, RTNLGRP_TC, 0);
1779         } else {
1780                 kfree_skb(skb);
1781         }
1782
1783         return ret;
1784 }
1785
1786 int tcf_action_reoffload_cb(flow_indr_block_bind_cb_t *cb,
1787                             void *cb_priv, bool add)
1788 {
1789         struct tc_act_pernet_id *id_ptr;
1790         struct tcf_idrinfo *idrinfo;
1791         struct tc_action_net *tn;
1792         struct tc_action *p;
1793         unsigned int act_id;
1794         unsigned long tmp;
1795         unsigned long id;
1796         struct idr *idr;
1797         struct net *net;
1798         int ret;
1799
1800         if (!cb)
1801                 return -EINVAL;
1802
1803         down_read(&net_rwsem);
1804         mutex_lock(&act_id_mutex);
1805
1806         for_each_net(net) {
1807                 list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
1808                         act_id = id_ptr->id;
1809                         tn = net_generic(net, act_id);
1810                         if (!tn)
1811                                 continue;
1812                         idrinfo = tn->idrinfo;
1813                         if (!idrinfo)
1814                                 continue;
1815
1816                         mutex_lock(&idrinfo->lock);
1817                         idr = &idrinfo->action_idr;
1818                         idr_for_each_entry_ul(idr, p, tmp, id) {
1819                                 if (IS_ERR(p) || tc_act_bind(p->tcfa_flags))
1820                                         continue;
1821                                 if (add) {
1822                                         tcf_action_offload_add_ex(p, NULL, cb,
1823                                                                   cb_priv);
1824                                         continue;
1825                                 }
1826
1827                                 /* cb unregister to update hw count */
1828                                 ret = tcf_action_offload_del_ex(p, cb, cb_priv);
1829                                 if (ret < 0)
1830                                         continue;
1831                                 if (tc_act_skip_sw(p->tcfa_flags) &&
1832                                     !tc_act_in_hw(p))
1833                                         tcf_reoffload_del_notify(net, p);
1834                         }
1835                         mutex_unlock(&idrinfo->lock);
1836                 }
1837         }
1838         mutex_unlock(&act_id_mutex);
1839         up_read(&net_rwsem);
1840
1841         return 0;
1842 }
1843
1844 static int
1845 tcf_del_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[],
1846                u32 portid, size_t attr_size, struct netlink_ext_ack *extack)
1847 {
1848         int ret;
1849         struct sk_buff *skb;
1850
1851         skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1852                         GFP_KERNEL);
1853         if (!skb)
1854                 return -ENOBUFS;
1855
1856         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, RTM_DELACTION,
1857                          0, 2) <= 0) {
1858                 NL_SET_ERR_MSG(extack, "Failed to fill netlink TC action attributes");
1859                 kfree_skb(skb);
1860                 return -EINVAL;
1861         }
1862
1863         /* now do the delete */
1864         ret = tcf_action_delete(net, actions);
1865         if (ret < 0) {
1866                 NL_SET_ERR_MSG(extack, "Failed to delete TC action");
1867                 kfree_skb(skb);
1868                 return ret;
1869         }
1870
1871         ret = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1872                              n->nlmsg_flags & NLM_F_ECHO);
1873         return ret;
1874 }
1875
1876 static int
1877 tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
1878               u32 portid, int event, struct netlink_ext_ack *extack)
1879 {
1880         int i, ret;
1881         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1882         struct tc_action *act;
1883         size_t attr_size = 0;
1884         struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
1885
1886         ret = nla_parse_nested_deprecated(tb, TCA_ACT_MAX_PRIO, nla, NULL,
1887                                           extack);
1888         if (ret < 0)
1889                 return ret;
1890
1891         if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) {
1892                 if (tb[1])
1893                         return tca_action_flush(net, tb[1], n, portid, extack);
1894
1895                 NL_SET_ERR_MSG(extack, "Invalid netlink attributes while flushing TC action");
1896                 return -EINVAL;
1897         }
1898
1899         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1900                 act = tcf_action_get_1(net, tb[i], n, portid, extack);
1901                 if (IS_ERR(act)) {
1902                         ret = PTR_ERR(act);
1903                         goto err;
1904                 }
1905                 attr_size += tcf_action_fill_size(act);
1906                 actions[i - 1] = act;
1907         }
1908
1909         attr_size = tcf_action_full_attrs_size(attr_size);
1910
1911         if (event == RTM_GETACTION)
1912                 ret = tcf_get_notify(net, portid, n, actions, event, extack);
1913         else { /* delete */
1914                 ret = tcf_del_notify(net, n, actions, portid, attr_size, extack);
1915                 if (ret)
1916                         goto err;
1917                 return 0;
1918         }
1919 err:
1920         tcf_action_put_many(actions);
1921         return ret;
1922 }
1923
1924 static int
1925 tcf_add_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[],
1926                u32 portid, size_t attr_size, struct netlink_ext_ack *extack)
1927 {
1928         struct sk_buff *skb;
1929
1930         skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1931                         GFP_KERNEL);
1932         if (!skb)
1933                 return -ENOBUFS;
1934
1935         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, n->nlmsg_flags,
1936                          RTM_NEWACTION, 0, 0) <= 0) {
1937                 NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1938                 kfree_skb(skb);
1939                 return -EINVAL;
1940         }
1941
1942         return rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1943                               n->nlmsg_flags & NLM_F_ECHO);
1944 }
1945
1946 static int tcf_action_add(struct net *net, struct nlattr *nla,
1947                           struct nlmsghdr *n, u32 portid, u32 flags,
1948                           struct netlink_ext_ack *extack)
1949 {
1950         size_t attr_size = 0;
1951         int loop, ret, i;
1952         struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
1953         int init_res[TCA_ACT_MAX_PRIO] = {};
1954
1955         for (loop = 0; loop < 10; loop++) {
1956                 ret = tcf_action_init(net, NULL, nla, NULL, actions, init_res,
1957                                       &attr_size, flags, 0, extack);
1958                 if (ret != -EAGAIN)
1959                         break;
1960         }
1961
1962         if (ret < 0)
1963                 return ret;
1964         ret = tcf_add_notify(net, n, actions, portid, attr_size, extack);
1965
1966         /* only put existing actions */
1967         for (i = 0; i < TCA_ACT_MAX_PRIO; i++)
1968                 if (init_res[i] == ACT_P_CREATED)
1969                         actions[i] = NULL;
1970         tcf_action_put_many(actions);
1971
1972         return ret;
1973 }
1974
1975 static const struct nla_policy tcaa_policy[TCA_ROOT_MAX + 1] = {
1976         [TCA_ROOT_FLAGS] = NLA_POLICY_BITFIELD32(TCA_ACT_FLAG_LARGE_DUMP_ON |
1977                                                  TCA_ACT_FLAG_TERSE_DUMP),
1978         [TCA_ROOT_TIME_DELTA]      = { .type = NLA_U32 },
1979 };
1980
1981 static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n,
1982                          struct netlink_ext_ack *extack)
1983 {
1984         struct net *net = sock_net(skb->sk);
1985         struct nlattr *tca[TCA_ROOT_MAX + 1];
1986         u32 portid = NETLINK_CB(skb).portid;
1987         u32 flags = 0;
1988         int ret = 0;
1989
1990         if ((n->nlmsg_type != RTM_GETACTION) &&
1991             !netlink_capable(skb, CAP_NET_ADMIN))
1992                 return -EPERM;
1993
1994         ret = nlmsg_parse_deprecated(n, sizeof(struct tcamsg), tca,
1995                                      TCA_ROOT_MAX, NULL, extack);
1996         if (ret < 0)
1997                 return ret;
1998
1999         if (tca[TCA_ACT_TAB] == NULL) {
2000                 NL_SET_ERR_MSG(extack, "Netlink action attributes missing");
2001                 return -EINVAL;
2002         }
2003
2004         /* n->nlmsg_flags & NLM_F_CREATE */
2005         switch (n->nlmsg_type) {
2006         case RTM_NEWACTION:
2007                 /* we are going to assume all other flags
2008                  * imply create only if it doesn't exist
2009                  * Note that CREATE | EXCL implies that
2010                  * but since we want avoid ambiguity (eg when flags
2011                  * is zero) then just set this
2012                  */
2013                 if (n->nlmsg_flags & NLM_F_REPLACE)
2014                         flags = TCA_ACT_FLAGS_REPLACE;
2015                 ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, portid, flags,
2016                                      extack);
2017                 break;
2018         case RTM_DELACTION:
2019                 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
2020                                     portid, RTM_DELACTION, extack);
2021                 break;
2022         case RTM_GETACTION:
2023                 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
2024                                     portid, RTM_GETACTION, extack);
2025                 break;
2026         default:
2027                 BUG();
2028         }
2029
2030         return ret;
2031 }
2032
2033 static struct nlattr *find_dump_kind(struct nlattr **nla)
2034 {
2035         struct nlattr *tb1, *tb2[TCA_ACT_MAX + 1];
2036         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
2037         struct nlattr *kind;
2038
2039         tb1 = nla[TCA_ACT_TAB];
2040         if (tb1 == NULL)
2041                 return NULL;
2042
2043         if (nla_parse_deprecated(tb, TCA_ACT_MAX_PRIO, nla_data(tb1), NLMSG_ALIGN(nla_len(tb1)), NULL, NULL) < 0)
2044                 return NULL;
2045
2046         if (tb[1] == NULL)
2047                 return NULL;
2048         if (nla_parse_nested_deprecated(tb2, TCA_ACT_MAX, tb[1], tcf_action_policy, NULL) < 0)
2049                 return NULL;
2050         kind = tb2[TCA_ACT_KIND];
2051
2052         return kind;
2053 }
2054
2055 static int tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
2056 {
2057         struct net *net = sock_net(skb->sk);
2058         struct nlmsghdr *nlh;
2059         unsigned char *b = skb_tail_pointer(skb);
2060         struct nlattr *nest;
2061         struct tc_action_ops *a_o;
2062         int ret = 0;
2063         struct tcamsg *t = (struct tcamsg *) nlmsg_data(cb->nlh);
2064         struct nlattr *tb[TCA_ROOT_MAX + 1];
2065         struct nlattr *count_attr = NULL;
2066         unsigned long jiffy_since = 0;
2067         struct nlattr *kind = NULL;
2068         struct nla_bitfield32 bf;
2069         u32 msecs_since = 0;
2070         u32 act_count = 0;
2071
2072         ret = nlmsg_parse_deprecated(cb->nlh, sizeof(struct tcamsg), tb,
2073                                      TCA_ROOT_MAX, tcaa_policy, cb->extack);
2074         if (ret < 0)
2075                 return ret;
2076
2077         kind = find_dump_kind(tb);
2078         if (kind == NULL) {
2079                 pr_info("tc_dump_action: action bad kind\n");
2080                 return 0;
2081         }
2082
2083         a_o = tc_lookup_action(kind);
2084         if (a_o == NULL)
2085                 return 0;
2086
2087         cb->args[2] = 0;
2088         if (tb[TCA_ROOT_FLAGS]) {
2089                 bf = nla_get_bitfield32(tb[TCA_ROOT_FLAGS]);
2090                 cb->args[2] = bf.value;
2091         }
2092
2093         if (tb[TCA_ROOT_TIME_DELTA]) {
2094                 msecs_since = nla_get_u32(tb[TCA_ROOT_TIME_DELTA]);
2095         }
2096
2097         nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
2098                         cb->nlh->nlmsg_type, sizeof(*t), 0);
2099         if (!nlh)
2100                 goto out_module_put;
2101
2102         if (msecs_since)
2103                 jiffy_since = jiffies - msecs_to_jiffies(msecs_since);
2104
2105         t = nlmsg_data(nlh);
2106         t->tca_family = AF_UNSPEC;
2107         t->tca__pad1 = 0;
2108         t->tca__pad2 = 0;
2109         cb->args[3] = jiffy_since;
2110         count_attr = nla_reserve(skb, TCA_ROOT_COUNT, sizeof(u32));
2111         if (!count_attr)
2112                 goto out_module_put;
2113
2114         nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
2115         if (nest == NULL)
2116                 goto out_module_put;
2117
2118         ret = a_o->walk(net, skb, cb, RTM_GETACTION, a_o, NULL);
2119         if (ret < 0)
2120                 goto out_module_put;
2121
2122         if (ret > 0) {
2123                 nla_nest_end(skb, nest);
2124                 ret = skb->len;
2125                 act_count = cb->args[1];
2126                 memcpy(nla_data(count_attr), &act_count, sizeof(u32));
2127                 cb->args[1] = 0;
2128         } else
2129                 nlmsg_trim(skb, b);
2130
2131         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
2132         if (NETLINK_CB(cb->skb).portid && ret)
2133                 nlh->nlmsg_flags |= NLM_F_MULTI;
2134         module_put(a_o->owner);
2135         return skb->len;
2136
2137 out_module_put:
2138         module_put(a_o->owner);
2139         nlmsg_trim(skb, b);
2140         return skb->len;
2141 }
2142
2143 static int __init tc_action_init(void)
2144 {
2145         rtnl_register(PF_UNSPEC, RTM_NEWACTION, tc_ctl_action, NULL, 0);
2146         rtnl_register(PF_UNSPEC, RTM_DELACTION, tc_ctl_action, NULL, 0);
2147         rtnl_register(PF_UNSPEC, RTM_GETACTION, tc_ctl_action, tc_dump_action,
2148                       0);
2149
2150         return 0;
2151 }
2152
2153 subsys_initcall(tc_action_init);