net/sched/act_api.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * net/sched/act_api.c  Packet action API.
   4  *
   5  * Author:      Jamal Hadi Salim
   6  */
   7
   8 #include <linux/types.h>
   9 #include <linux/kernel.h>
  10 #include <linux/string.h>
  11 #include <linux/errno.h>
  12 #include <linux/slab.h>
  13 #include <linux/skbuff.h>
  14 #include <linux/init.h>
  15 #include <linux/kmod.h>
  16 #include <linux/err.h>
  17 #include <linux/module.h>
  18 #include <net/net_namespace.h>
  19 #include <net/sock.h>
  20 #include <net/sch_generic.h>
  21 #include <net/pkt_cls.h>
  22 #include <net/tc_act/tc_pedit.h>
  23 #include <net/act_api.h>
  24 #include <net/netlink.h>
  25 #include <net/flow_offload.h>
  26 #include <net/tc_wrapper.h>
  27
  28 #ifdef CONFIG_INET
  29 DEFINE_STATIC_KEY_FALSE(tcf_frag_xmit_count);
  30 EXPORT_SYMBOL_GPL(tcf_frag_xmit_count);
  31 #endif
  32
  33 int tcf_dev_queue_xmit(struct sk_buff *skb, int (*xmit)(struct sk_buff *skb))
  34 {
  35 #ifdef CONFIG_INET
  36         if (static_branch_unlikely(&tcf_frag_xmit_count))
  37                 return sch_frag_xmit_hook(skb, xmit);
  38 #endif
  39
  40         return xmit(skb);
  41 }
  42 EXPORT_SYMBOL_GPL(tcf_dev_queue_xmit);
  43
  44 static void tcf_action_goto_chain_exec(const struct tc_action *a,
  45                                        struct tcf_result *res)
  46 {
  47         const struct tcf_chain *chain = rcu_dereference_bh(a->goto_chain);
  48
  49         res->goto_tp = rcu_dereference_bh(chain->filter_chain);
  50 }
  51
  52 static void tcf_free_cookie_rcu(struct rcu_head *p)
  53 {
  54         struct tc_cookie *cookie = container_of(p, struct tc_cookie, rcu);
  55
  56         kfree(cookie->data);
  57         kfree(cookie);
  58 }
  59
  60 static void tcf_set_action_cookie(struct tc_cookie __rcu **old_cookie,
  61                                   struct tc_cookie *new_cookie)
  62 {
  63         struct tc_cookie *old;
  64
  65         old = unrcu_pointer(xchg(old_cookie, RCU_INITIALIZER(new_cookie)));
  66         if (old)
  67                 call_rcu(&old->rcu, tcf_free_cookie_rcu);
  68 }
  69
  70 int tcf_action_check_ctrlact(int action, struct tcf_proto *tp,
  71                              struct tcf_chain **newchain,
  72                              struct netlink_ext_ack *extack)
  73 {
  74         int opcode = TC_ACT_EXT_OPCODE(action), ret = -EINVAL;
  75         u32 chain_index;
  76
  77         if (!opcode)
  78                 ret = action > TC_ACT_VALUE_MAX ? -EINVAL : 0;
  79         else if (opcode <= TC_ACT_EXT_OPCODE_MAX || action == TC_ACT_UNSPEC)
  80                 ret = 0;
  81         if (ret) {
  82                 NL_SET_ERR_MSG(extack, "invalid control action");
  83                 goto end;
  84         }
  85
  86         if (TC_ACT_EXT_CMP(action, TC_ACT_GOTO_CHAIN)) {
  87                 chain_index = action & TC_ACT_EXT_VAL_MASK;
  88                 if (!tp || !newchain) {
  89                         ret = -EINVAL;
  90                         NL_SET_ERR_MSG(extack,
  91                                        "can't goto NULL proto/chain");
  92                         goto end;
  93                 }
  94                 *newchain = tcf_chain_get_by_act(tp->chain->block, chain_index);
  95                 if (!*newchain) {
  96                         ret = -ENOMEM;
  97                         NL_SET_ERR_MSG(extack,
  98                                        "can't allocate goto_chain");
  99                 }
 100         }
 101 end:
 102         return ret;
 103 }
 104 EXPORT_SYMBOL(tcf_action_check_ctrlact);
 105
 106 struct tcf_chain *tcf_action_set_ctrlact(struct tc_action *a, int action,
 107                                          struct tcf_chain *goto_chain)
 108 {
 109         a->tcfa_action = action;
 110         goto_chain = rcu_replace_pointer(a->goto_chain, goto_chain, 1);
 111         return goto_chain;
 112 }
 113 EXPORT_SYMBOL(tcf_action_set_ctrlact);
 114
 115 /* XXX: For standalone actions, we don't need a RCU grace period either, because
 116  * actions are always connected to filters and filters are already destroyed in
 117  * RCU callbacks, so after a RCU grace period actions are already disconnected
 118  * from filters. Readers later can not find us.
 119  */
 120 static void free_tcf(struct tc_action *p)
 121 {
 122         struct tcf_chain *chain = rcu_dereference_protected(p->goto_chain, 1);
 123
 124         free_percpu(p->cpu_bstats);
 125         free_percpu(p->cpu_bstats_hw);
 126         free_percpu(p->cpu_qstats);
 127
 128         tcf_set_action_cookie(&p->user_cookie, NULL);
 129         if (chain)
 130                 tcf_chain_put_by_act(chain);
 131
 132         kfree(p);
 133 }
 134
 135 static void offload_action_hw_count_set(struct tc_action *act,
 136                                         u32 hw_count)
 137 {
 138         act->in_hw_count = hw_count;
 139 }
 140
 141 static void offload_action_hw_count_inc(struct tc_action *act,
 142                                         u32 hw_count)
 143 {
 144         act->in_hw_count += hw_count;
 145 }
 146
 147 static void offload_action_hw_count_dec(struct tc_action *act,
 148                                         u32 hw_count)
 149 {
 150         act->in_hw_count = act->in_hw_count > hw_count ?
 151                            act->in_hw_count - hw_count : 0;
 152 }
 153
 154 static unsigned int tcf_offload_act_num_actions_single(struct tc_action *act)
 155 {
 156         if (is_tcf_pedit(act))
 157                 return tcf_pedit_nkeys(act);
 158         else
 159                 return 1;
 160 }
 161
 162 static bool tc_act_skip_hw(u32 flags)
 163 {
 164         return (flags & TCA_ACT_FLAGS_SKIP_HW) ? true : false;
 165 }
 166
 167 static bool tc_act_skip_sw(u32 flags)
 168 {
 169         return (flags & TCA_ACT_FLAGS_SKIP_SW) ? true : false;
 170 }
 171
 172 /* SKIP_HW and SKIP_SW are mutually exclusive flags. */
 173 static bool tc_act_flags_valid(u32 flags)
 174 {
 175         flags &= TCA_ACT_FLAGS_SKIP_HW | TCA_ACT_FLAGS_SKIP_SW;
 176
 177         return flags ^ (TCA_ACT_FLAGS_SKIP_HW | TCA_ACT_FLAGS_SKIP_SW);
 178 }
 179
 180 static int offload_action_init(struct flow_offload_action *fl_action,
 181                                struct tc_action *act,
 182                                enum offload_act_command  cmd,
 183                                struct netlink_ext_ack *extack)
 184 {
 185         int err;
 186
 187         fl_action->extack = extack;
 188         fl_action->command = cmd;
 189         fl_action->index = act->tcfa_index;
 190         fl_action->cookie = (unsigned long)act;
 191
 192         if (act->ops->offload_act_setup) {
 193                 spin_lock_bh(&act->tcfa_lock);
 194                 err = act->ops->offload_act_setup(act, fl_action, NULL,
 195                                                   false, extack);
 196                 spin_unlock_bh(&act->tcfa_lock);
 197                 return err;
 198         }
 199
 200         return -EOPNOTSUPP;
 201 }
 202
 203 static int tcf_action_offload_cmd_ex(struct flow_offload_action *fl_act,
 204                                      u32 *hw_count)
 205 {
 206         int err;
 207
 208         err = flow_indr_dev_setup_offload(NULL, NULL, TC_SETUP_ACT,
 209                                           fl_act, NULL, NULL);
 210         if (err < 0)
 211                 return err;
 212
 213         if (hw_count)
 214                 *hw_count = err;
 215
 216         return 0;
 217 }
 218
 219 static int tcf_action_offload_cmd_cb_ex(struct flow_offload_action *fl_act,
 220                                         u32 *hw_count,
 221                                         flow_indr_block_bind_cb_t *cb,
 222                                         void *cb_priv)
 223 {
 224         int err;
 225
 226         err = cb(NULL, NULL, cb_priv, TC_SETUP_ACT, NULL, fl_act, NULL);
 227         if (err < 0)
 228                 return err;
 229
 230         if (hw_count)
 231                 *hw_count = 1;
 232
 233         return 0;
 234 }
 235
 236 static int tcf_action_offload_cmd(struct flow_offload_action *fl_act,
 237                                   u32 *hw_count,
 238                                   flow_indr_block_bind_cb_t *cb,
 239                                   void *cb_priv)
 240 {
 241         return cb ? tcf_action_offload_cmd_cb_ex(fl_act, hw_count,
 242                                                  cb, cb_priv) :
 243                     tcf_action_offload_cmd_ex(fl_act, hw_count);
 244 }
 245
 246 static int tcf_action_offload_add_ex(struct tc_action *action,
 247                                      struct netlink_ext_ack *extack,
 248                                      flow_indr_block_bind_cb_t *cb,
 249                                      void *cb_priv)
 250 {
 251         bool skip_sw = tc_act_skip_sw(action->tcfa_flags);
 252         struct tc_action *actions[TCA_ACT_MAX_PRIO] = {
 253                 [0] = action,
 254         };
 255         struct flow_offload_action *fl_action;
 256         u32 in_hw_count = 0;
 257         int num, err = 0;
 258
 259         if (tc_act_skip_hw(action->tcfa_flags))
 260                 return 0;
 261
 262         num = tcf_offload_act_num_actions_single(action);
 263         fl_action = offload_action_alloc(num);
 264         if (!fl_action)
 265                 return -ENOMEM;
 266
 267         err = offload_action_init(fl_action, action, FLOW_ACT_REPLACE, extack);
 268         if (err)
 269                 goto fl_err;
 270
 271         err = tc_setup_action(&fl_action->action, actions, 0, extack);
 272         if (err) {
 273                 NL_SET_ERR_MSG_MOD(extack,
 274                                    "Failed to setup tc actions for offload");
 275                 goto fl_err;
 276         }
 277
 278         err = tcf_action_offload_cmd(fl_action, &in_hw_count, cb, cb_priv);
 279         if (!err)
 280                 cb ? offload_action_hw_count_inc(action, in_hw_count) :
 281                      offload_action_hw_count_set(action, in_hw_count);
 282
 283         if (skip_sw && !tc_act_in_hw(action))
 284                 err = -EINVAL;
 285
 286         tc_cleanup_offload_action(&fl_action->action);
 287
 288 fl_err:
 289         kfree(fl_action);
 290
 291         return err;
 292 }
 293
 294 /* offload the tc action after it is inserted */
 295 static int tcf_action_offload_add(struct tc_action *action,
 296                                   struct netlink_ext_ack *extack)
 297 {
 298         return tcf_action_offload_add_ex(action, extack, NULL, NULL);
 299 }
 300
 301 int tcf_action_update_hw_stats(struct tc_action *action)
 302 {
 303         struct flow_offload_action fl_act = {};
 304         int err;
 305
 306         err = offload_action_init(&fl_act, action, FLOW_ACT_STATS, NULL);
 307         if (err)
 308                 return err;
 309
 310         err = tcf_action_offload_cmd(&fl_act, NULL, NULL, NULL);
 311         if (!err) {
 312                 preempt_disable();
 313                 tcf_action_stats_update(action, fl_act.stats.bytes,
 314                                         fl_act.stats.pkts,
 315                                         fl_act.stats.drops,
 316                                         fl_act.stats.lastused,
 317                                         true);
 318                 preempt_enable();
 319                 action->used_hw_stats = fl_act.stats.used_hw_stats;
 320                 action->used_hw_stats_valid = true;
 321         } else {
 322                 return -EOPNOTSUPP;
 323         }
 324
 325         return 0;
 326 }
 327 EXPORT_SYMBOL(tcf_action_update_hw_stats);
 328
 329 static int tcf_action_offload_del_ex(struct tc_action *action,
 330                                      flow_indr_block_bind_cb_t *cb,
 331                                      void *cb_priv)
 332 {
 333         struct flow_offload_action fl_act = {};
 334         u32 in_hw_count = 0;
 335         int err = 0;
 336
 337         if (!tc_act_in_hw(action))
 338                 return 0;
 339
 340         err = offload_action_init(&fl_act, action, FLOW_ACT_DESTROY, NULL);
 341         if (err)
 342                 return err;
 343
 344         err = tcf_action_offload_cmd(&fl_act, &in_hw_count, cb, cb_priv);
 345         if (err < 0)
 346                 return err;
 347
 348         if (!cb && action->in_hw_count != in_hw_count)
 349                 return -EINVAL;
 350
 351         /* do not need to update hw state when deleting action */
 352         if (cb && in_hw_count)
 353                 offload_action_hw_count_dec(action, in_hw_count);
 354
 355         return 0;
 356 }
 357
 358 static int tcf_action_offload_del(struct tc_action *action)
 359 {
 360         return tcf_action_offload_del_ex(action, NULL, NULL);
 361 }
 362
 363 static void tcf_action_cleanup(struct tc_action *p)
 364 {
 365         tcf_action_offload_del(p);
 366         if (p->ops->cleanup)
 367                 p->ops->cleanup(p);
 368
 369         gen_kill_estimator(&p->tcfa_rate_est);
 370         free_tcf(p);
 371 }
 372
 373 static int __tcf_action_put(struct tc_action *p, bool bind)
 374 {
 375         struct tcf_idrinfo *idrinfo = p->idrinfo;
 376
 377         if (refcount_dec_and_mutex_lock(&p->tcfa_refcnt, &idrinfo->lock)) {
 378                 if (bind)
 379                         atomic_dec(&p->tcfa_bindcnt);
 380                 idr_remove(&idrinfo->action_idr, p->tcfa_index);
 381                 mutex_unlock(&idrinfo->lock);
 382
 383                 tcf_action_cleanup(p);
 384                 return 1;
 385         }
 386
 387         if (bind)
 388                 atomic_dec(&p->tcfa_bindcnt);
 389
 390         return 0;
 391 }
 392
 393 static int __tcf_idr_release(struct tc_action *p, bool bind, bool strict)
 394 {
 395         int ret = 0;
 396
 397         /* Release with strict==1 and bind==0 is only called through act API
 398          * interface (classifiers always bind). Only case when action with
 399          * positive reference count and zero bind count can exist is when it was
 400          * also created with act API (unbinding last classifier will destroy the
 401          * action if it was created by classifier). So only case when bind count
 402          * can be changed after initial check is when unbound action is
 403          * destroyed by act API while classifier binds to action with same id
 404          * concurrently. This result either creation of new action(same behavior
 405          * as before), or reusing existing action if concurrent process
 406          * increments reference count before action is deleted. Both scenarios
 407          * are acceptable.
 408          */
 409         if (p) {
 410                 if (!bind && strict && atomic_read(&p->tcfa_bindcnt) > 0)
 411                         return -EPERM;
 412
 413                 if (__tcf_action_put(p, bind))
 414                         ret = ACT_P_DELETED;
 415         }
 416
 417         return ret;
 418 }
 419
 420 int tcf_idr_release(struct tc_action *a, bool bind)
 421 {
 422         const struct tc_action_ops *ops = a->ops;
 423         int ret;
 424
 425         ret = __tcf_idr_release(a, bind, false);
 426         if (ret == ACT_P_DELETED)
 427                 module_put(ops->owner);
 428         return ret;
 429 }
 430 EXPORT_SYMBOL(tcf_idr_release);
 431
 432 static size_t tcf_action_shared_attrs_size(const struct tc_action *act)
 433 {
 434         struct tc_cookie *user_cookie;
 435         u32 cookie_len = 0;
 436
 437         rcu_read_lock();
 438         user_cookie = rcu_dereference(act->user_cookie);
 439
 440         if (user_cookie)
 441                 cookie_len = nla_total_size(user_cookie->len);
 442         rcu_read_unlock();
 443
 444         return  nla_total_size(0) /* action number nested */
 445                 + nla_total_size(IFNAMSIZ) /* TCA_ACT_KIND */
 446                 + cookie_len /* TCA_ACT_COOKIE */
 447                 + nla_total_size(sizeof(struct nla_bitfield32)) /* TCA_ACT_HW_STATS */
 448                 + nla_total_size(0) /* TCA_ACT_STATS nested */
 449                 + nla_total_size(sizeof(struct nla_bitfield32)) /* TCA_ACT_FLAGS */
 450                 /* TCA_STATS_BASIC */
 451                 + nla_total_size_64bit(sizeof(struct gnet_stats_basic))
 452                 /* TCA_STATS_PKT64 */
 453                 + nla_total_size_64bit(sizeof(u64))
 454                 /* TCA_STATS_QUEUE */
 455                 + nla_total_size_64bit(sizeof(struct gnet_stats_queue))
 456                 + nla_total_size(0) /* TCA_ACT_OPTIONS nested */
 457                 + nla_total_size(sizeof(struct tcf_t)); /* TCA_GACT_TM */
 458 }
 459
 460 static size_t tcf_action_full_attrs_size(size_t sz)
 461 {
 462         return NLMSG_HDRLEN                     /* struct nlmsghdr */
 463                 + sizeof(struct tcamsg)
 464                 + nla_total_size(0)             /* TCA_ACT_TAB nested */
 465                 + sz;
 466 }
 467
 468 static size_t tcf_action_fill_size(const struct tc_action *act)
 469 {
 470         size_t sz = tcf_action_shared_attrs_size(act);
 471
 472         if (act->ops->get_fill_size)
 473                 return act->ops->get_fill_size(act) + sz;
 474         return sz;
 475 }
 476
 477 static int
 478 tcf_action_dump_terse(struct sk_buff *skb, struct tc_action *a, bool from_act)
 479 {
 480         unsigned char *b = skb_tail_pointer(skb);
 481         struct tc_cookie *cookie;
 482
 483         if (nla_put_string(skb, TCA_ACT_KIND, a->ops->kind))
 484                 goto nla_put_failure;
 485         if (tcf_action_copy_stats(skb, a, 0))
 486                 goto nla_put_failure;
 487         if (from_act && nla_put_u32(skb, TCA_ACT_INDEX, a->tcfa_index))
 488                 goto nla_put_failure;
 489
 490         rcu_read_lock();
 491         cookie = rcu_dereference(a->user_cookie);
 492         if (cookie) {
 493                 if (nla_put(skb, TCA_ACT_COOKIE, cookie->len, cookie->data)) {
 494                         rcu_read_unlock();
 495                         goto nla_put_failure;
 496                 }
 497         }
 498         rcu_read_unlock();
 499
 500         return 0;
 501
 502 nla_put_failure:
 503         nlmsg_trim(skb, b);
 504         return -1;
 505 }
 506
 507 static int
 508 tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 509 {
 510         unsigned char *b = skb_tail_pointer(skb);
 511         struct nlattr *nest;
 512         int err = -EINVAL;
 513         u32 flags;
 514
 515         if (tcf_action_dump_terse(skb, a, false))
 516                 goto nla_put_failure;
 517
 518         if (a->hw_stats != TCA_ACT_HW_STATS_ANY &&
 519             nla_put_bitfield32(skb, TCA_ACT_HW_STATS,
 520                                a->hw_stats, TCA_ACT_HW_STATS_ANY))
 521                 goto nla_put_failure;
 522
 523         if (a->used_hw_stats_valid &&
 524             nla_put_bitfield32(skb, TCA_ACT_USED_HW_STATS,
 525                                a->used_hw_stats, TCA_ACT_HW_STATS_ANY))
 526                 goto nla_put_failure;
 527
 528         flags = a->tcfa_flags & TCA_ACT_FLAGS_USER_MASK;
 529         if (flags &&
 530             nla_put_bitfield32(skb, TCA_ACT_FLAGS,
 531                                flags, flags))
 532                 goto nla_put_failure;
 533
 534         if (nla_put_u32(skb, TCA_ACT_IN_HW_COUNT, a->in_hw_count))
 535                 goto nla_put_failure;
 536
 537         nest = nla_nest_start_noflag(skb, TCA_ACT_OPTIONS);
 538         if (nest == NULL)
 539                 goto nla_put_failure;
 540         err = tcf_action_dump_old(skb, a, bind, ref);
 541         if (err > 0) {
 542                 nla_nest_end(skb, nest);
 543                 return err;
 544         }
 545
 546 nla_put_failure:
 547         nlmsg_trim(skb, b);
 548         return -1;
 549 }
 550
 551 static int tcf_dump_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb,
 552                            struct netlink_callback *cb)
 553 {
 554         int err = 0, index = -1, s_i = 0, n_i = 0;
 555         u32 act_flags = cb->args[2];
 556         unsigned long jiffy_since = cb->args[3];
 557         struct nlattr *nest;
 558         struct idr *idr = &idrinfo->action_idr;
 559         struct tc_action *p;
 560         unsigned long id = 1;
 561         unsigned long tmp;
 562
 563         mutex_lock(&idrinfo->lock);
 564
 565         s_i = cb->args[0];
 566
 567         idr_for_each_entry_ul(idr, p, tmp, id) {
 568                 index++;
 569                 if (index < s_i)
 570                         continue;
 571                 if (IS_ERR(p))
 572                         continue;
 573
 574                 if (jiffy_since &&
 575                     time_after(jiffy_since,
 576                                (unsigned long)p->tcfa_tm.lastuse))
 577                         continue;
 578
 579                 tcf_action_update_hw_stats(p);
 580
 581                 nest = nla_nest_start_noflag(skb, n_i);
 582                 if (!nest) {
 583                         index--;
 584                         goto nla_put_failure;
 585                 }
 586                 err = (act_flags & TCA_ACT_FLAG_TERSE_DUMP) ?
 587                         tcf_action_dump_terse(skb, p, true) :
 588                         tcf_action_dump_1(skb, p, 0, 0);
 589                 if (err < 0) {
 590                         index--;
 591                         nlmsg_trim(skb, nest);
 592                         goto done;
 593                 }
 594                 nla_nest_end(skb, nest);
 595                 n_i++;
 596                 if (!(act_flags & TCA_ACT_FLAG_LARGE_DUMP_ON) &&
 597                     n_i >= TCA_ACT_MAX_PRIO)
 598                         goto done;
 599         }
 600 done:
 601         if (index >= 0)
 602                 cb->args[0] = index + 1;
 603
 604         mutex_unlock(&idrinfo->lock);
 605         if (n_i) {
 606                 if (act_flags & TCA_ACT_FLAG_LARGE_DUMP_ON)
 607                         cb->args[1] = n_i;
 608         }
 609         return n_i;
 610
 611 nla_put_failure:
 612         nla_nest_cancel(skb, nest);
 613         goto done;
 614 }
 615
 616 static int tcf_idr_release_unsafe(struct tc_action *p)
 617 {
 618         if (atomic_read(&p->tcfa_bindcnt) > 0)
 619                 return -EPERM;
 620
 621         if (refcount_dec_and_test(&p->tcfa_refcnt)) {
 622                 idr_remove(&p->idrinfo->action_idr, p->tcfa_index);
 623                 tcf_action_cleanup(p);
 624                 return ACT_P_DELETED;
 625         }
 626
 627         return 0;
 628 }
 629
 630 static int tcf_del_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb,
 631                           const struct tc_action_ops *ops,
 632                           struct netlink_ext_ack *extack)
 633 {
 634         struct nlattr *nest;
 635         int n_i = 0;
 636         int ret = -EINVAL;
 637         struct idr *idr = &idrinfo->action_idr;
 638         struct tc_action *p;
 639         unsigned long id = 1;
 640         unsigned long tmp;
 641
 642         nest = nla_nest_start_noflag(skb, 0);
 643         if (nest == NULL)
 644                 goto nla_put_failure;
 645         if (nla_put_string(skb, TCA_ACT_KIND, ops->kind))
 646                 goto nla_put_failure;
 647
 648         ret = 0;
 649         mutex_lock(&idrinfo->lock);
 650         idr_for_each_entry_ul(idr, p, tmp, id) {
 651                 if (IS_ERR(p))
 652                         continue;
 653                 ret = tcf_idr_release_unsafe(p);
 654                 if (ret == ACT_P_DELETED)
 655                         module_put(ops->owner);
 656                 else if (ret < 0)
 657                         break;
 658                 n_i++;
 659         }
 660         mutex_unlock(&idrinfo->lock);
 661         if (ret < 0) {
 662                 if (n_i)
 663                         NL_SET_ERR_MSG(extack, "Unable to flush all TC actions");
 664                 else
 665                         goto nla_put_failure;
 666         }
 667
 668         ret = nla_put_u32(skb, TCA_FCNT, n_i);
 669         if (ret)
 670                 goto nla_put_failure;
 671         nla_nest_end(skb, nest);
 672
 673         return n_i;
 674 nla_put_failure:
 675         nla_nest_cancel(skb, nest);
 676         return ret;
 677 }
 678
 679 int tcf_generic_walker(struct tc_action_net *tn, 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 tcf_idrinfo *idrinfo = tn->idrinfo;
 685
 686         if (type == RTM_DELACTION) {
 687                 return tcf_del_walker(idrinfo, skb, ops, extack);
 688         } else if (type == RTM_GETACTION) {
 689                 return tcf_dump_walker(idrinfo, skb, cb);
 690         } else {
 691                 WARN(1, "tcf_generic_walker: unknown command %d\n", type);
 692                 NL_SET_ERR_MSG(extack, "tcf_generic_walker: unknown command");
 693                 return -EINVAL;
 694         }
 695 }
 696 EXPORT_SYMBOL(tcf_generic_walker);
 697
 698 int tcf_idr_search(struct tc_action_net *tn, struct tc_action **a, u32 index)
 699 {
 700         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 701         struct tc_action *p;
 702
 703         mutex_lock(&idrinfo->lock);
 704         p = idr_find(&idrinfo->action_idr, index);
 705         if (IS_ERR(p))
 706                 p = NULL;
 707         else if (p)
 708                 refcount_inc(&p->tcfa_refcnt);
 709         mutex_unlock(&idrinfo->lock);
 710
 711         if (p) {
 712                 *a = p;
 713                 return true;
 714         }
 715         return false;
 716 }
 717 EXPORT_SYMBOL(tcf_idr_search);
 718
 719 static int __tcf_generic_walker(struct net *net, struct sk_buff *skb,
 720                                 struct netlink_callback *cb, int type,
 721                                 const struct tc_action_ops *ops,
 722                                 struct netlink_ext_ack *extack)
 723 {
 724         struct tc_action_net *tn = net_generic(net, ops->net_id);
 725
 726         if (unlikely(ops->walk))
 727                 return ops->walk(net, skb, cb, type, ops, extack);
 728
 729         return tcf_generic_walker(tn, skb, cb, type, ops, extack);
 730 }
 731
 732 static int __tcf_idr_search(struct net *net,
 733                             const struct tc_action_ops *ops,
 734                             struct tc_action **a, u32 index)
 735 {
 736         struct tc_action_net *tn = net_generic(net, ops->net_id);
 737
 738         if (unlikely(ops->lookup))
 739                 return ops->lookup(net, a, index);
 740
 741         return tcf_idr_search(tn, a, index);
 742 }
 743
 744 static int tcf_idr_delete_index(struct tcf_idrinfo *idrinfo, u32 index)
 745 {
 746         struct tc_action *p;
 747         int ret = 0;
 748
 749         mutex_lock(&idrinfo->lock);
 750         p = idr_find(&idrinfo->action_idr, index);
 751         if (!p) {
 752                 mutex_unlock(&idrinfo->lock);
 753                 return -ENOENT;
 754         }
 755
 756         if (!atomic_read(&p->tcfa_bindcnt)) {
 757                 if (refcount_dec_and_test(&p->tcfa_refcnt)) {
 758                         struct module *owner = p->ops->owner;
 759
 760                         WARN_ON(p != idr_remove(&idrinfo->action_idr,
 761                                                 p->tcfa_index));
 762                         mutex_unlock(&idrinfo->lock);
 763
 764                         tcf_action_cleanup(p);
 765                         module_put(owner);
 766                         return 0;
 767                 }
 768                 ret = 0;
 769         } else {
 770                 ret = -EPERM;
 771         }
 772
 773         mutex_unlock(&idrinfo->lock);
 774         return ret;
 775 }
 776
 777 int tcf_idr_create(struct tc_action_net *tn, u32 index, struct nlattr *est,
 778                    struct tc_action **a, const struct tc_action_ops *ops,
 779                    int bind, bool cpustats, u32 flags)
 780 {
 781         struct tc_action *p = kzalloc(ops->size, GFP_KERNEL);
 782         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 783         int err = -ENOMEM;
 784
 785         if (unlikely(!p))
 786                 return -ENOMEM;
 787         refcount_set(&p->tcfa_refcnt, 1);
 788         if (bind)
 789                 atomic_set(&p->tcfa_bindcnt, 1);
 790
 791         if (cpustats) {
 792                 p->cpu_bstats = netdev_alloc_pcpu_stats(struct gnet_stats_basic_sync);
 793                 if (!p->cpu_bstats)
 794                         goto err1;
 795                 p->cpu_bstats_hw = netdev_alloc_pcpu_stats(struct gnet_stats_basic_sync);
 796                 if (!p->cpu_bstats_hw)
 797                         goto err2;
 798                 p->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
 799                 if (!p->cpu_qstats)
 800                         goto err3;
 801         }
 802         gnet_stats_basic_sync_init(&p->tcfa_bstats);
 803         gnet_stats_basic_sync_init(&p->tcfa_bstats_hw);
 804         spin_lock_init(&p->tcfa_lock);
 805         p->tcfa_index = index;
 806         p->tcfa_tm.install = jiffies;
 807         p->tcfa_tm.lastuse = jiffies;
 808         p->tcfa_tm.firstuse = 0;
 809         p->tcfa_flags = flags;
 810         if (est) {
 811                 err = gen_new_estimator(&p->tcfa_bstats, p->cpu_bstats,
 812                                         &p->tcfa_rate_est,
 813                                         &p->tcfa_lock, false, est);
 814                 if (err)
 815                         goto err4;
 816         }
 817
 818         p->idrinfo = idrinfo;
 819         __module_get(ops->owner);
 820         p->ops = ops;
 821         *a = p;
 822         return 0;
 823 err4:
 824         free_percpu(p->cpu_qstats);
 825 err3:
 826         free_percpu(p->cpu_bstats_hw);
 827 err2:
 828         free_percpu(p->cpu_bstats);
 829 err1:
 830         kfree(p);
 831         return err;
 832 }
 833 EXPORT_SYMBOL(tcf_idr_create);
 834
 835 int tcf_idr_create_from_flags(struct tc_action_net *tn, u32 index,
 836                               struct nlattr *est, struct tc_action **a,
 837                               const struct tc_action_ops *ops, int bind,
 838                               u32 flags)
 839 {
 840         /* Set cpustats according to actions flags. */
 841         return tcf_idr_create(tn, index, est, a, ops, bind,
 842                               !(flags & TCA_ACT_FLAGS_NO_PERCPU_STATS), flags);
 843 }
 844 EXPORT_SYMBOL(tcf_idr_create_from_flags);
 845
 846 /* Cleanup idr index that was allocated but not initialized. */
 847
 848 void tcf_idr_cleanup(struct tc_action_net *tn, u32 index)
 849 {
 850         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 851
 852         mutex_lock(&idrinfo->lock);
 853         /* Remove ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */
 854         WARN_ON(!IS_ERR(idr_remove(&idrinfo->action_idr, index)));
 855         mutex_unlock(&idrinfo->lock);
 856 }
 857 EXPORT_SYMBOL(tcf_idr_cleanup);
 858
 859 /* Check if action with specified index exists. If actions is found, increments
 860  * its reference and bind counters, and return 1. Otherwise insert temporary
 861  * error pointer (to prevent concurrent users from inserting actions with same
 862  * index) and return 0.
 863  *
 864  * May return -EAGAIN for binding actions in case of a parallel add/delete on
 865  * the requested index.
 866  */
 867
 868 int tcf_idr_check_alloc(struct tc_action_net *tn, u32 *index,
 869                         struct tc_action **a, int bind)
 870 {
 871         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 872         struct tc_action *p;
 873         int ret;
 874         u32 max;
 875
 876         if (*index) {
 877                 rcu_read_lock();
 878                 p = idr_find(&idrinfo->action_idr, *index);
 879
 880                 if (IS_ERR(p)) {
 881                         /* This means that another process allocated
 882                          * index but did not assign the pointer yet.
 883                          */
 884                         rcu_read_unlock();
 885                         return -EAGAIN;
 886                 }
 887
 888                 if (!p) {
 889                         /* Empty slot, try to allocate it */
 890                         max = *index;
 891                         rcu_read_unlock();
 892                         goto new;
 893                 }
 894
 895                 if (!refcount_inc_not_zero(&p->tcfa_refcnt)) {
 896                         /* Action was deleted in parallel */
 897                         rcu_read_unlock();
 898                         return -EAGAIN;
 899                 }
 900
 901                 if (bind)
 902                         atomic_inc(&p->tcfa_bindcnt);
 903                 *a = p;
 904
 905                 rcu_read_unlock();
 906
 907                 return 1;
 908         } else {
 909                 /* Find a slot */
 910                 *index = 1;
 911                 max = UINT_MAX;
 912         }
 913
 914 new:
 915         *a = NULL;
 916
 917         mutex_lock(&idrinfo->lock);
 918         ret = idr_alloc_u32(&idrinfo->action_idr, ERR_PTR(-EBUSY), index, max,
 919                             GFP_KERNEL);
 920         mutex_unlock(&idrinfo->lock);
 921
 922         /* N binds raced for action allocation,
 923          * retry for all the ones that failed.
 924          */
 925         if (ret == -ENOSPC && *index == max)
 926                 ret = -EAGAIN;
 927
 928         return ret;
 929 }
 930 EXPORT_SYMBOL(tcf_idr_check_alloc);
 931
 932 void tcf_idrinfo_destroy(const struct tc_action_ops *ops,
 933                          struct tcf_idrinfo *idrinfo)
 934 {
 935         struct idr *idr = &idrinfo->action_idr;
 936         struct tc_action *p;
 937         int ret;
 938         unsigned long id = 1;
 939         unsigned long tmp;
 940
 941         idr_for_each_entry_ul(idr, p, tmp, id) {
 942                 ret = __tcf_idr_release(p, false, true);
 943                 if (ret == ACT_P_DELETED)
 944                         module_put(ops->owner);
 945                 else if (ret < 0)
 946                         return;
 947         }
 948         idr_destroy(&idrinfo->action_idr);
 949 }
 950 EXPORT_SYMBOL(tcf_idrinfo_destroy);
 951
 952 static LIST_HEAD(act_base);
 953 static DEFINE_RWLOCK(act_mod_lock);
 954 /* since act ops id is stored in pernet subsystem list,
 955  * then there is no way to walk through only all the action
 956  * subsystem, so we keep tc action pernet ops id for
 957  * reoffload to walk through.
 958  */
 959 static LIST_HEAD(act_pernet_id_list);
 960 static DEFINE_MUTEX(act_id_mutex);
 961 struct tc_act_pernet_id {
 962         struct list_head list;
 963         unsigned int id;
 964 };
 965
 966 static int tcf_pernet_add_id_list(unsigned int id)
 967 {
 968         struct tc_act_pernet_id *id_ptr;
 969         int ret = 0;
 970
 971         mutex_lock(&act_id_mutex);
 972         list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
 973                 if (id_ptr->id == id) {
 974                         ret = -EEXIST;
 975                         goto err_out;
 976                 }
 977         }
 978
 979         id_ptr = kzalloc(sizeof(*id_ptr), GFP_KERNEL);
 980         if (!id_ptr) {
 981                 ret = -ENOMEM;
 982                 goto err_out;
 983         }
 984         id_ptr->id = id;
 985
 986         list_add_tail(&id_ptr->list, &act_pernet_id_list);
 987
 988 err_out:
 989         mutex_unlock(&act_id_mutex);
 990         return ret;
 991 }
 992
 993 static void tcf_pernet_del_id_list(unsigned int id)
 994 {
 995         struct tc_act_pernet_id *id_ptr;
 996
 997         mutex_lock(&act_id_mutex);
 998         list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
 999                 if (id_ptr->id == id) {
1000                         list_del(&id_ptr->list);
1001                         kfree(id_ptr);
1002                         break;
1003                 }
1004         }
1005         mutex_unlock(&act_id_mutex);
1006 }
1007
1008 int tcf_register_action(struct tc_action_ops *act,
1009                         struct pernet_operations *ops)
1010 {
1011         struct tc_action_ops *a;
1012         int ret;
1013
1014         if (!act->act || !act->dump || !act->init)
1015                 return -EINVAL;
1016
1017         /* We have to register pernet ops before making the action ops visible,
1018          * otherwise tcf_action_init_1() could get a partially initialized
1019          * netns.
1020          */
1021         ret = register_pernet_subsys(ops);
1022         if (ret)
1023                 return ret;
1024
1025         if (ops->id) {
1026                 ret = tcf_pernet_add_id_list(*ops->id);
1027                 if (ret)
1028                         goto err_id;
1029         }
1030
1031         write_lock(&act_mod_lock);
1032         list_for_each_entry(a, &act_base, head) {
1033                 if (act->id == a->id || (strcmp(act->kind, a->kind) == 0)) {
1034                         ret = -EEXIST;
1035                         goto err_out;
1036                 }
1037         }
1038         list_add_tail(&act->head, &act_base);
1039         write_unlock(&act_mod_lock);
1040
1041         return 0;
1042
1043 err_out:
1044         write_unlock(&act_mod_lock);
1045         if (ops->id)
1046                 tcf_pernet_del_id_list(*ops->id);
1047 err_id:
1048         unregister_pernet_subsys(ops);
1049         return ret;
1050 }
1051 EXPORT_SYMBOL(tcf_register_action);
1052
1053 int tcf_unregister_action(struct tc_action_ops *act,
1054                           struct pernet_operations *ops)
1055 {
1056         struct tc_action_ops *a;
1057         int err = -ENOENT;
1058
1059         write_lock(&act_mod_lock);
1060         list_for_each_entry(a, &act_base, head) {
1061                 if (a == act) {
1062                         list_del(&act->head);
1063                         err = 0;
1064                         break;
1065                 }
1066         }
1067         write_unlock(&act_mod_lock);
1068         if (!err) {
1069                 unregister_pernet_subsys(ops);
1070                 if (ops->id)
1071                         tcf_pernet_del_id_list(*ops->id);
1072         }
1073         return err;
1074 }
1075 EXPORT_SYMBOL(tcf_unregister_action);
1076
1077 /* lookup by name */
1078 static struct tc_action_ops *tc_lookup_action_n(char *kind)
1079 {
1080         struct tc_action_ops *a, *res = NULL;
1081
1082         if (kind) {
1083                 read_lock(&act_mod_lock);
1084                 list_for_each_entry(a, &act_base, head) {
1085                         if (strcmp(kind, a->kind) == 0) {
1086                                 if (try_module_get(a->owner))
1087                                         res = a;
1088                                 break;
1089                         }
1090                 }
1091                 read_unlock(&act_mod_lock);
1092         }
1093         return res;
1094 }
1095
1096 /* lookup by nlattr */
1097 static struct tc_action_ops *tc_lookup_action(struct nlattr *kind)
1098 {
1099         struct tc_action_ops *a, *res = NULL;
1100
1101         if (kind) {
1102                 read_lock(&act_mod_lock);
1103                 list_for_each_entry(a, &act_base, head) {
1104                         if (nla_strcmp(kind, a->kind) == 0) {
1105                                 if (try_module_get(a->owner))
1106                                         res = a;
1107                                 break;
1108                         }
1109                 }
1110                 read_unlock(&act_mod_lock);
1111         }
1112         return res;
1113 }
1114
1115 /*TCA_ACT_MAX_PRIO is 32, there count up to 32 */
1116 #define TCA_ACT_MAX_PRIO_MASK 0x1FF
1117 int tcf_action_exec(struct sk_buff *skb, struct tc_action **actions,
1118                     int nr_actions, struct tcf_result *res)
1119 {
1120         u32 jmp_prgcnt = 0;
1121         u32 jmp_ttl = TCA_ACT_MAX_PRIO; /*matches actions per filter */
1122         int i;
1123         int ret = TC_ACT_OK;
1124
1125         if (skb_skip_tc_classify(skb))
1126                 return TC_ACT_OK;
1127
1128 restart_act_graph:
1129         for (i = 0; i < nr_actions; i++) {
1130                 const struct tc_action *a = actions[i];
1131                 int repeat_ttl;
1132
1133                 if (jmp_prgcnt > 0) {
1134                         jmp_prgcnt -= 1;
1135                         continue;
1136                 }
1137
1138                 if (tc_act_skip_sw(a->tcfa_flags))
1139                         continue;
1140
1141                 repeat_ttl = 32;
1142 repeat:
1143                 ret = tc_act(skb, a, res);
1144                 if (unlikely(ret == TC_ACT_REPEAT)) {
1145                         if (--repeat_ttl != 0)
1146                                 goto repeat;
1147                         /* suspicious opcode, stop pipeline */
1148                         net_warn_ratelimited("TC_ACT_REPEAT abuse ?\n");
1149                         return TC_ACT_OK;
1150                 }
1151                 if (TC_ACT_EXT_CMP(ret, TC_ACT_JUMP)) {
1152                         jmp_prgcnt = ret & TCA_ACT_MAX_PRIO_MASK;
1153                         if (!jmp_prgcnt || (jmp_prgcnt > nr_actions)) {
1154                                 /* faulty opcode, stop pipeline */
1155                                 return TC_ACT_OK;
1156                         } else {
1157                                 jmp_ttl -= 1;
1158                                 if (jmp_ttl > 0)
1159                                         goto restart_act_graph;
1160                                 else /* faulty graph, stop pipeline */
1161                                         return TC_ACT_OK;
1162                         }
1163                 } else if (TC_ACT_EXT_CMP(ret, TC_ACT_GOTO_CHAIN)) {
1164                         if (unlikely(!rcu_access_pointer(a->goto_chain))) {
1165                                 tcf_set_drop_reason(skb,
1166                                                     SKB_DROP_REASON_TC_CHAIN_NOTFOUND);
1167                                 return TC_ACT_SHOT;
1168                         }
1169                         tcf_action_goto_chain_exec(a, res);
1170                 }
1171
1172                 if (ret != TC_ACT_PIPE)
1173                         break;
1174         }
1175
1176         return ret;
1177 }
1178 EXPORT_SYMBOL(tcf_action_exec);
1179
1180 int tcf_action_destroy(struct tc_action *actions[], int bind)
1181 {
1182         const struct tc_action_ops *ops;
1183         struct tc_action *a;
1184         int ret = 0, i;
1185
1186         tcf_act_for_each_action(i, a, actions) {
1187                 actions[i] = NULL;
1188                 ops = a->ops;
1189                 ret = __tcf_idr_release(a, bind, true);
1190                 if (ret == ACT_P_DELETED)
1191                         module_put(ops->owner);
1192                 else if (ret < 0)
1193                         return ret;
1194         }
1195         return ret;
1196 }
1197
1198 static int tcf_action_put(struct tc_action *p)
1199 {
1200         return __tcf_action_put(p, false);
1201 }
1202
1203 static void tcf_action_put_many(struct tc_action *actions[])
1204 {
1205         struct tc_action *a;
1206         int i;
1207
1208         tcf_act_for_each_action(i, a, actions) {
1209                 const struct tc_action_ops *ops = a->ops;
1210                 if (tcf_action_put(a))
1211                         module_put(ops->owner);
1212         }
1213 }
1214
1215 static void tca_put_bound_many(struct tc_action *actions[], int init_res[])
1216 {
1217         struct tc_action *a;
1218         int i;
1219
1220         tcf_act_for_each_action(i, a, actions) {
1221                 const struct tc_action_ops *ops = a->ops;
1222
1223                 if (init_res[i] == ACT_P_CREATED)
1224                         continue;
1225
1226                 if (tcf_action_put(a))
1227                         module_put(ops->owner);
1228         }
1229 }
1230
1231 int
1232 tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
1233 {
1234         return a->ops->dump(skb, a, bind, ref);
1235 }
1236
1237 int tcf_action_dump(struct sk_buff *skb, struct tc_action *actions[],
1238                     int bind, int ref, bool terse)
1239 {
1240         struct tc_action *a;
1241         int err = -EINVAL, i;
1242         struct nlattr *nest;
1243
1244         tcf_act_for_each_action(i, a, actions) {
1245                 nest = nla_nest_start_noflag(skb, i + 1);
1246                 if (nest == NULL)
1247                         goto nla_put_failure;
1248                 err = terse ? tcf_action_dump_terse(skb, a, false) :
1249                         tcf_action_dump_1(skb, a, bind, ref);
1250                 if (err < 0)
1251                         goto errout;
1252                 nla_nest_end(skb, nest);
1253         }
1254
1255         return 0;
1256
1257 nla_put_failure:
1258         err = -EINVAL;
1259 errout:
1260         nla_nest_cancel(skb, nest);
1261         return err;
1262 }
1263
1264 static struct tc_cookie *nla_memdup_cookie(struct nlattr **tb)
1265 {
1266         struct tc_cookie *c = kzalloc(sizeof(*c), GFP_KERNEL);
1267         if (!c)
1268                 return NULL;
1269
1270         c->data = nla_memdup(tb[TCA_ACT_COOKIE], GFP_KERNEL);
1271         if (!c->data) {
1272                 kfree(c);
1273                 return NULL;
1274         }
1275         c->len = nla_len(tb[TCA_ACT_COOKIE]);
1276
1277         return c;
1278 }
1279
1280 static u8 tcf_action_hw_stats_get(struct nlattr *hw_stats_attr)
1281 {
1282         struct nla_bitfield32 hw_stats_bf;
1283
1284         /* If the user did not pass the attr, that means he does
1285          * not care about the type. Return "any" in that case
1286          * which is setting on all supported types.
1287          */
1288         if (!hw_stats_attr)
1289                 return TCA_ACT_HW_STATS_ANY;
1290         hw_stats_bf = nla_get_bitfield32(hw_stats_attr);
1291         return hw_stats_bf.value;
1292 }
1293
1294 static const struct nla_policy tcf_action_policy[TCA_ACT_MAX + 1] = {
1295         [TCA_ACT_KIND]          = { .type = NLA_STRING },
1296         [TCA_ACT_INDEX]         = { .type = NLA_U32 },
1297         [TCA_ACT_COOKIE]        = { .type = NLA_BINARY,
1298                                     .len = TC_COOKIE_MAX_SIZE },
1299         [TCA_ACT_OPTIONS]       = { .type = NLA_NESTED },
1300         [TCA_ACT_FLAGS]         = NLA_POLICY_BITFIELD32(TCA_ACT_FLAGS_NO_PERCPU_STATS |
1301                                                         TCA_ACT_FLAGS_SKIP_HW |
1302                                                         TCA_ACT_FLAGS_SKIP_SW),
1303         [TCA_ACT_HW_STATS]      = NLA_POLICY_BITFIELD32(TCA_ACT_HW_STATS_ANY),
1304 };
1305
1306 void tcf_idr_insert_many(struct tc_action *actions[], int init_res[])
1307 {
1308         struct tc_action *a;
1309         int i;
1310
1311         tcf_act_for_each_action(i, a, actions) {
1312                 struct tcf_idrinfo *idrinfo;
1313
1314                 if (init_res[i] == ACT_P_BOUND)
1315                         continue;
1316
1317                 idrinfo = a->idrinfo;
1318                 mutex_lock(&idrinfo->lock);
1319                 /* Replace ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */
1320                 idr_replace(&idrinfo->action_idr, a, a->tcfa_index);
1321                 mutex_unlock(&idrinfo->lock);
1322         }
1323 }
1324
1325 struct tc_action_ops *tc_action_load_ops(struct nlattr *nla, u32 flags,
1326                                          struct netlink_ext_ack *extack)
1327 {
1328         bool police = flags & TCA_ACT_FLAGS_POLICE;
1329         struct nlattr *tb[TCA_ACT_MAX + 1];
1330         struct tc_action_ops *a_o;
1331         char act_name[IFNAMSIZ];
1332         struct nlattr *kind;
1333         int err;
1334
1335         if (!police) {
1336                 err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1337                                                   tcf_action_policy, extack);
1338                 if (err < 0)
1339                         return ERR_PTR(err);
1340                 err = -EINVAL;
1341                 kind = tb[TCA_ACT_KIND];
1342                 if (!kind) {
1343                         NL_SET_ERR_MSG(extack, "TC action kind must be specified");
1344                         return ERR_PTR(err);
1345                 }
1346                 if (nla_strscpy(act_name, kind, IFNAMSIZ) < 0) {
1347                         NL_SET_ERR_MSG(extack, "TC action name too long");
1348                         return ERR_PTR(err);
1349                 }
1350         } else {
1351                 if (strscpy(act_name, "police", IFNAMSIZ) < 0) {
1352                         NL_SET_ERR_MSG(extack, "TC action name too long");
1353                         return ERR_PTR(-EINVAL);
1354                 }
1355         }
1356
1357         a_o = tc_lookup_action_n(act_name);
1358         if (a_o == NULL) {
1359 #ifdef CONFIG_MODULES
1360                 bool rtnl_held = !(flags & TCA_ACT_FLAGS_NO_RTNL);
1361
1362                 if (rtnl_held)
1363                         rtnl_unlock();
1364                 request_module(NET_ACT_ALIAS_PREFIX "%s", act_name);
1365                 if (rtnl_held)
1366                         rtnl_lock();
1367
1368                 a_o = tc_lookup_action_n(act_name);
1369
1370                 /* We dropped the RTNL semaphore in order to
1371                  * perform the module load.  So, even if we
1372                  * succeeded in loading the module we have to
1373                  * tell the caller to replay the request.  We
1374                  * indicate this using -EAGAIN.
1375                  */
1376                 if (a_o != NULL) {
1377                         module_put(a_o->owner);
1378                         return ERR_PTR(-EAGAIN);
1379                 }
1380 #endif
1381                 NL_SET_ERR_MSG(extack, "Failed to load TC action module");
1382                 return ERR_PTR(-ENOENT);
1383         }
1384
1385         return a_o;
1386 }
1387
1388 struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
1389                                     struct nlattr *nla, struct nlattr *est,
1390                                     struct tc_action_ops *a_o, int *init_res,
1391                                     u32 flags, struct netlink_ext_ack *extack)
1392 {
1393         bool police = flags & TCA_ACT_FLAGS_POLICE;
1394         struct nla_bitfield32 userflags = { 0, 0 };
1395         struct tc_cookie *user_cookie = NULL;
1396         u8 hw_stats = TCA_ACT_HW_STATS_ANY;
1397         struct nlattr *tb[TCA_ACT_MAX + 1];
1398         struct tc_action *a;
1399         int err;
1400
1401         /* backward compatibility for policer */
1402         if (!police) {
1403                 err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1404                                                   tcf_action_policy, extack);
1405                 if (err < 0)
1406                         return ERR_PTR(err);
1407                 if (tb[TCA_ACT_COOKIE]) {
1408                         user_cookie = nla_memdup_cookie(tb);
1409                         if (!user_cookie) {
1410                                 NL_SET_ERR_MSG(extack, "No memory to generate TC cookie");
1411                                 err = -ENOMEM;
1412                                 goto err_out;
1413                         }
1414                 }
1415                 hw_stats = tcf_action_hw_stats_get(tb[TCA_ACT_HW_STATS]);
1416                 if (tb[TCA_ACT_FLAGS]) {
1417                         userflags = nla_get_bitfield32(tb[TCA_ACT_FLAGS]);
1418                         if (!tc_act_flags_valid(userflags.value)) {
1419                                 err = -EINVAL;
1420                                 goto err_out;
1421                         }
1422                 }
1423
1424                 err = a_o->init(net, tb[TCA_ACT_OPTIONS], est, &a, tp,
1425                                 userflags.value | flags, extack);
1426         } else {
1427                 err = a_o->init(net, nla, est, &a, tp, userflags.value | flags,
1428                                 extack);
1429         }
1430         if (err < 0)
1431                 goto err_out;
1432         *init_res = err;
1433
1434         if (!police && tb[TCA_ACT_COOKIE])
1435                 tcf_set_action_cookie(&a->user_cookie, user_cookie);
1436
1437         if (!police)
1438                 a->hw_stats = hw_stats;
1439
1440         return a;
1441
1442 err_out:
1443         if (user_cookie) {
1444                 kfree(user_cookie->data);
1445                 kfree(user_cookie);
1446         }
1447         return ERR_PTR(err);
1448 }
1449
1450 static bool tc_act_bind(u32 flags)
1451 {
1452         return !!(flags & TCA_ACT_FLAGS_BIND);
1453 }
1454
1455 /* Returns numbers of initialized actions or negative error. */
1456
1457 int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla,
1458                     struct nlattr *est, struct tc_action *actions[],
1459                     int init_res[], size_t *attr_size,
1460                     u32 flags, u32 fl_flags,
1461                     struct netlink_ext_ack *extack)
1462 {
1463         struct tc_action_ops *ops[TCA_ACT_MAX_PRIO] = {};
1464         struct nlattr *tb[TCA_ACT_MAX_PRIO + 2];
1465         struct tc_action *act;
1466         size_t sz = 0;
1467         int err;
1468         int i;
1469
1470         err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX_PRIO + 1, nla, NULL,
1471                                           extack);
1472         if (err < 0)
1473                 return err;
1474
1475         /* The nested attributes are parsed as types, but they are really an
1476          * array of actions. So we parse one more than we can handle, and return
1477          * an error if the last one is set (as that indicates that the request
1478          * contained more than the maximum number of actions).
1479          */
1480         if (tb[TCA_ACT_MAX_PRIO + 1]) {
1481                 NL_SET_ERR_MSG_FMT(extack,
1482                                    "Only %d actions supported per filter",
1483                                    TCA_ACT_MAX_PRIO);
1484                 return -EINVAL;
1485         }
1486
1487         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1488                 struct tc_action_ops *a_o;
1489
1490                 a_o = tc_action_load_ops(tb[i], flags, extack);
1491                 if (IS_ERR(a_o)) {
1492                         err = PTR_ERR(a_o);
1493                         goto err_mod;
1494                 }
1495                 ops[i - 1] = a_o;
1496         }
1497
1498         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1499                 act = tcf_action_init_1(net, tp, tb[i], est, ops[i - 1],
1500                                         &init_res[i - 1], flags, extack);
1501                 if (IS_ERR(act)) {
1502                         err = PTR_ERR(act);
1503                         goto err;
1504                 }
1505                 sz += tcf_action_fill_size(act);
1506                 /* Start from index 0 */
1507                 actions[i - 1] = act;
1508                 if (tc_act_bind(flags)) {
1509                         bool skip_sw = tc_skip_sw(fl_flags);
1510                         bool skip_hw = tc_skip_hw(fl_flags);
1511
1512                         if (tc_act_bind(act->tcfa_flags)) {
1513                                 /* Action is created by classifier and is not
1514                                  * standalone. Check that the user did not set
1515                                  * any action flags different than the
1516                                  * classifier flags, and inherit the flags from
1517                                  * the classifier for the compatibility case
1518                                  * where no flags were specified at all.
1519                                  */
1520                                 if ((tc_act_skip_sw(act->tcfa_flags) && !skip_sw) ||
1521                                     (tc_act_skip_hw(act->tcfa_flags) && !skip_hw)) {
1522                                         NL_SET_ERR_MSG(extack,
1523                                                        "Mismatch between action and filter offload flags");
1524                                         err = -EINVAL;
1525                                         goto err;
1526                                 }
1527                                 if (skip_sw)
1528                                         act->tcfa_flags |= TCA_ACT_FLAGS_SKIP_SW;
1529                                 if (skip_hw)
1530                                         act->tcfa_flags |= TCA_ACT_FLAGS_SKIP_HW;
1531                                 continue;
1532                         }
1533
1534                         /* Action is standalone */
1535                         if (skip_sw != tc_act_skip_sw(act->tcfa_flags) ||
1536                             skip_hw != tc_act_skip_hw(act->tcfa_flags)) {
1537                                 NL_SET_ERR_MSG(extack,
1538                                                "Mismatch between action and filter offload flags");
1539                                 err = -EINVAL;
1540                                 goto err;
1541                         }
1542                 } else {
1543                         err = tcf_action_offload_add(act, extack);
1544                         if (tc_act_skip_sw(act->tcfa_flags) && err)
1545                                 goto err;
1546                 }
1547         }
1548
1549         /* We have to commit them all together, because if any error happened in
1550          * between, we could not handle the failure gracefully.
1551          */
1552         tcf_idr_insert_many(actions, init_res);
1553
1554         *attr_size = tcf_action_full_attrs_size(sz);
1555         err = i - 1;
1556         goto err_mod;
1557
1558 err:
1559         tcf_action_destroy(actions, flags & TCA_ACT_FLAGS_BIND);
1560 err_mod:
1561         for (i = 0; i < TCA_ACT_MAX_PRIO && ops[i]; i++)
1562                 module_put(ops[i]->owner);
1563         return err;
1564 }
1565
1566 void tcf_action_update_stats(struct tc_action *a, u64 bytes, u64 packets,
1567                              u64 drops, bool hw)
1568 {
1569         if (a->cpu_bstats) {
1570                 _bstats_update(this_cpu_ptr(a->cpu_bstats), bytes, packets);
1571
1572                 this_cpu_ptr(a->cpu_qstats)->drops += drops;
1573
1574                 if (hw)
1575                         _bstats_update(this_cpu_ptr(a->cpu_bstats_hw),
1576                                        bytes, packets);
1577                 return;
1578         }
1579
1580         _bstats_update(&a->tcfa_bstats, bytes, packets);
1581         a->tcfa_qstats.drops += drops;
1582         if (hw)
1583                 _bstats_update(&a->tcfa_bstats_hw, bytes, packets);
1584 }
1585 EXPORT_SYMBOL(tcf_action_update_stats);
1586
1587 int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *p,
1588                           int compat_mode)
1589 {
1590         int err = 0;
1591         struct gnet_dump d;
1592
1593         if (p == NULL)
1594                 goto errout;
1595
1596         /* compat_mode being true specifies a call that is supposed
1597          * to add additional backward compatibility statistic TLVs.
1598          */
1599         if (compat_mode) {
1600                 if (p->type == TCA_OLD_COMPAT)
1601                         err = gnet_stats_start_copy_compat(skb, 0,
1602                                                            TCA_STATS,
1603                                                            TCA_XSTATS,
1604                                                            &p->tcfa_lock, &d,
1605                                                            TCA_PAD);
1606                 else
1607                         return 0;
1608         } else
1609                 err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
1610                                             &p->tcfa_lock, &d, TCA_ACT_PAD);
1611
1612         if (err < 0)
1613                 goto errout;
1614
1615         if (gnet_stats_copy_basic(&d, p->cpu_bstats,
1616                                   &p->tcfa_bstats, false) < 0 ||
1617             gnet_stats_copy_basic_hw(&d, p->cpu_bstats_hw,
1618                                      &p->tcfa_bstats_hw, false) < 0 ||
1619             gnet_stats_copy_rate_est(&d, &p->tcfa_rate_est) < 0 ||
1620             gnet_stats_copy_queue(&d, p->cpu_qstats,
1621                                   &p->tcfa_qstats,
1622                                   p->tcfa_qstats.qlen) < 0)
1623                 goto errout;
1624
1625         if (gnet_stats_finish_copy(&d) < 0)
1626                 goto errout;
1627
1628         return 0;
1629
1630 errout:
1631         return -1;
1632 }
1633
1634 static int tca_get_fill(struct sk_buff *skb, struct tc_action *actions[],
1635                         u32 portid, u32 seq, u16 flags, int event, int bind,
1636                         int ref, struct netlink_ext_ack *extack)
1637 {
1638         struct tcamsg *t;
1639         struct nlmsghdr *nlh;
1640         unsigned char *b = skb_tail_pointer(skb);
1641         struct nlattr *nest;
1642
1643         nlh = nlmsg_put(skb, portid, seq, event, sizeof(*t), flags);
1644         if (!nlh)
1645                 goto out_nlmsg_trim;
1646         t = nlmsg_data(nlh);
1647         t->tca_family = AF_UNSPEC;
1648         t->tca__pad1 = 0;
1649         t->tca__pad2 = 0;
1650
1651         if (extack && extack->_msg &&
1652             nla_put_string(skb, TCA_ROOT_EXT_WARN_MSG, extack->_msg))
1653                 goto out_nlmsg_trim;
1654
1655         nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
1656         if (!nest)
1657                 goto out_nlmsg_trim;
1658
1659         if (tcf_action_dump(skb, actions, bind, ref, false) < 0)
1660                 goto out_nlmsg_trim;
1661
1662         nla_nest_end(skb, nest);
1663
1664         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1665
1666         return skb->len;
1667
1668 out_nlmsg_trim:
1669         nlmsg_trim(skb, b);
1670         return -1;
1671 }
1672
1673 static int
1674 tcf_get_notify(struct net *net, u32 portid, struct nlmsghdr *n,
1675                struct tc_action *actions[], int event,
1676                struct netlink_ext_ack *extack)
1677 {
1678         struct sk_buff *skb;
1679
1680         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1681         if (!skb)
1682                 return -ENOBUFS;
1683         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, event,
1684                          0, 1, NULL) <= 0) {
1685                 NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1686                 kfree_skb(skb);
1687                 return -EINVAL;
1688         }
1689
1690         return rtnl_unicast(skb, net, portid);
1691 }
1692
1693 static struct tc_action *tcf_action_get_1(struct net *net, struct nlattr *nla,
1694                                           struct nlmsghdr *n, u32 portid,
1695                                           struct netlink_ext_ack *extack)
1696 {
1697         struct nlattr *tb[TCA_ACT_MAX + 1];
1698         const struct tc_action_ops *ops;
1699         struct tc_action *a;
1700         int index;
1701         int err;
1702
1703         err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1704                                           tcf_action_policy, extack);
1705         if (err < 0)
1706                 goto err_out;
1707
1708         err = -EINVAL;
1709         if (tb[TCA_ACT_INDEX] == NULL ||
1710             nla_len(tb[TCA_ACT_INDEX]) < sizeof(index)) {
1711                 NL_SET_ERR_MSG(extack, "Invalid TC action index value");
1712                 goto err_out;
1713         }
1714         index = nla_get_u32(tb[TCA_ACT_INDEX]);
1715
1716         err = -EINVAL;
1717         ops = tc_lookup_action(tb[TCA_ACT_KIND]);
1718         if (!ops) { /* could happen in batch of actions */
1719                 NL_SET_ERR_MSG(extack, "Specified TC action kind not found");
1720                 goto err_out;
1721         }
1722         err = -ENOENT;
1723         if (__tcf_idr_search(net, ops, &a, index) == 0) {
1724                 NL_SET_ERR_MSG(extack, "TC action with specified index not found");
1725                 goto err_mod;
1726         }
1727
1728         module_put(ops->owner);
1729         return a;
1730
1731 err_mod:
1732         module_put(ops->owner);
1733 err_out:
1734         return ERR_PTR(err);
1735 }
1736
1737 static int tca_action_flush(struct net *net, struct nlattr *nla,
1738                             struct nlmsghdr *n, u32 portid,
1739                             struct netlink_ext_ack *extack)
1740 {
1741         struct sk_buff *skb;
1742         unsigned char *b;
1743         struct nlmsghdr *nlh;
1744         struct tcamsg *t;
1745         struct netlink_callback dcb;
1746         struct nlattr *nest;
1747         struct nlattr *tb[TCA_ACT_MAX + 1];
1748         const struct tc_action_ops *ops;
1749         struct nlattr *kind;
1750         int err = -ENOMEM;
1751
1752         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1753         if (!skb)
1754                 return err;
1755
1756         b = skb_tail_pointer(skb);
1757
1758         err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1759                                           tcf_action_policy, extack);
1760         if (err < 0)
1761                 goto err_out;
1762
1763         err = -EINVAL;
1764         kind = tb[TCA_ACT_KIND];
1765         ops = tc_lookup_action(kind);
1766         if (!ops) { /*some idjot trying to flush unknown action */
1767                 NL_SET_ERR_MSG(extack, "Cannot flush unknown TC action");
1768                 goto err_out;
1769         }
1770
1771         nlh = nlmsg_put(skb, portid, n->nlmsg_seq, RTM_DELACTION,
1772                         sizeof(*t), 0);
1773         if (!nlh) {
1774                 NL_SET_ERR_MSG(extack, "Failed to create TC action flush notification");
1775                 goto out_module_put;
1776         }
1777         t = nlmsg_data(nlh);
1778         t->tca_family = AF_UNSPEC;
1779         t->tca__pad1 = 0;
1780         t->tca__pad2 = 0;
1781
1782         nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
1783         if (!nest) {
1784                 NL_SET_ERR_MSG(extack, "Failed to add new netlink message");
1785                 goto out_module_put;
1786         }
1787
1788         err = __tcf_generic_walker(net, skb, &dcb, RTM_DELACTION, ops, extack);
1789         if (err <= 0) {
1790                 nla_nest_cancel(skb, nest);
1791                 goto out_module_put;
1792         }
1793
1794         nla_nest_end(skb, nest);
1795
1796         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1797         nlh->nlmsg_flags |= NLM_F_ROOT;
1798         module_put(ops->owner);
1799         err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1800                              n->nlmsg_flags & NLM_F_ECHO);
1801         if (err < 0)
1802                 NL_SET_ERR_MSG(extack, "Failed to send TC action flush notification");
1803
1804         return err;
1805
1806 out_module_put:
1807         module_put(ops->owner);
1808 err_out:
1809         kfree_skb(skb);
1810         return err;
1811 }
1812
1813 static int tcf_action_delete(struct net *net, struct tc_action *actions[])
1814 {
1815         struct tc_action *a;
1816         int i;
1817
1818         tcf_act_for_each_action(i, a, actions) {
1819                 const struct tc_action_ops *ops = a->ops;
1820                 /* Actions can be deleted concurrently so we must save their
1821                  * type and id to search again after reference is released.
1822                  */
1823                 struct tcf_idrinfo *idrinfo = a->idrinfo;
1824                 u32 act_index = a->tcfa_index;
1825
1826                 actions[i] = NULL;
1827                 if (tcf_action_put(a)) {
1828                         /* last reference, action was deleted concurrently */
1829                         module_put(ops->owner);
1830                 } else {
1831                         int ret;
1832
1833                         /* now do the delete */
1834                         ret = tcf_idr_delete_index(idrinfo, act_index);
1835                         if (ret < 0)
1836                                 return ret;
1837                 }
1838         }
1839         return 0;
1840 }
1841
1842 static struct sk_buff *tcf_reoffload_del_notify_msg(struct net *net,
1843                                                     struct tc_action *action)
1844 {
1845         size_t attr_size = tcf_action_fill_size(action);
1846         struct tc_action *actions[TCA_ACT_MAX_PRIO] = {
1847                 [0] = action,
1848         };
1849         struct sk_buff *skb;
1850
1851         skb = alloc_skb(max(attr_size, NLMSG_GOODSIZE), GFP_KERNEL);
1852         if (!skb)
1853                 return ERR_PTR(-ENOBUFS);
1854
1855         if (tca_get_fill(skb, actions, 0, 0, 0, RTM_DELACTION, 0, 1, NULL) <= 0) {
1856                 kfree_skb(skb);
1857                 return ERR_PTR(-EINVAL);
1858         }
1859
1860         return skb;
1861 }
1862
1863 static int tcf_reoffload_del_notify(struct net *net, struct tc_action *action)
1864 {
1865         const struct tc_action_ops *ops = action->ops;
1866         struct sk_buff *skb;
1867         int ret;
1868
1869         if (!rtnl_notify_needed(net, 0, RTNLGRP_TC)) {
1870                 skb = NULL;
1871         } else {
1872                 skb = tcf_reoffload_del_notify_msg(net, action);
1873                 if (IS_ERR(skb))
1874                         return PTR_ERR(skb);
1875         }
1876
1877         ret = tcf_idr_release_unsafe(action);
1878         if (ret == ACT_P_DELETED) {
1879                 module_put(ops->owner);
1880                 ret = rtnetlink_maybe_send(skb, net, 0, RTNLGRP_TC, 0);
1881         } else {
1882                 kfree_skb(skb);
1883         }
1884
1885         return ret;
1886 }
1887
1888 int tcf_action_reoffload_cb(flow_indr_block_bind_cb_t *cb,
1889                             void *cb_priv, bool add)
1890 {
1891         struct tc_act_pernet_id *id_ptr;
1892         struct tcf_idrinfo *idrinfo;
1893         struct tc_action_net *tn;
1894         struct tc_action *p;
1895         unsigned int act_id;
1896         unsigned long tmp;
1897         unsigned long id;
1898         struct idr *idr;
1899         struct net *net;
1900         int ret;
1901
1902         if (!cb)
1903                 return -EINVAL;
1904
1905         down_read(&net_rwsem);
1906         mutex_lock(&act_id_mutex);
1907
1908         for_each_net(net) {
1909                 list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
1910                         act_id = id_ptr->id;
1911                         tn = net_generic(net, act_id);
1912                         if (!tn)
1913                                 continue;
1914                         idrinfo = tn->idrinfo;
1915                         if (!idrinfo)
1916                                 continue;
1917
1918                         mutex_lock(&idrinfo->lock);
1919                         idr = &idrinfo->action_idr;
1920                         idr_for_each_entry_ul(idr, p, tmp, id) {
1921                                 if (IS_ERR(p) || tc_act_bind(p->tcfa_flags))
1922                                         continue;
1923                                 if (add) {
1924                                         tcf_action_offload_add_ex(p, NULL, cb,
1925                                                                   cb_priv);
1926                                         continue;
1927                                 }
1928
1929                                 /* cb unregister to update hw count */
1930                                 ret = tcf_action_offload_del_ex(p, cb, cb_priv);
1931                                 if (ret < 0)
1932                                         continue;
1933                                 if (tc_act_skip_sw(p->tcfa_flags) &&
1934                                     !tc_act_in_hw(p))
1935                                         tcf_reoffload_del_notify(net, p);
1936                         }
1937                         mutex_unlock(&idrinfo->lock);
1938                 }
1939         }
1940         mutex_unlock(&act_id_mutex);
1941         up_read(&net_rwsem);
1942
1943         return 0;
1944 }
1945
1946 static struct sk_buff *tcf_del_notify_msg(struct net *net, struct nlmsghdr *n,
1947                                           struct tc_action *actions[],
1948                                           u32 portid, size_t attr_size,
1949                                           struct netlink_ext_ack *extack)
1950 {
1951         struct sk_buff *skb;
1952
1953         skb = alloc_skb(max(attr_size, NLMSG_GOODSIZE), GFP_KERNEL);
1954         if (!skb)
1955                 return ERR_PTR(-ENOBUFS);
1956
1957         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, RTM_DELACTION,
1958                          0, 2, extack) <= 0) {
1959                 NL_SET_ERR_MSG(extack, "Failed to fill netlink TC action attributes");
1960                 kfree_skb(skb);
1961                 return ERR_PTR(-EINVAL);
1962         }
1963
1964         return skb;
1965 }
1966
1967 static int tcf_del_notify(struct net *net, struct nlmsghdr *n,
1968                           struct tc_action *actions[], u32 portid,
1969                           size_t attr_size, struct netlink_ext_ack *extack)
1970 {
1971         struct sk_buff *skb;
1972         int ret;
1973
1974         if (!rtnl_notify_needed(net, n->nlmsg_flags, RTNLGRP_TC)) {
1975                 skb = NULL;
1976         } else {
1977                 skb = tcf_del_notify_msg(net, n, actions, portid, attr_size,
1978                                          extack);
1979                 if (IS_ERR(skb))
1980                         return PTR_ERR(skb);
1981         }
1982
1983         /* now do the delete */
1984         ret = tcf_action_delete(net, actions);
1985         if (ret < 0) {
1986                 NL_SET_ERR_MSG(extack, "Failed to delete TC action");
1987                 kfree_skb(skb);
1988                 return ret;
1989         }
1990
1991         return rtnetlink_maybe_send(skb, net, portid, RTNLGRP_TC,
1992                                     n->nlmsg_flags & NLM_F_ECHO);
1993 }
1994
1995 static int
1996 tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
1997               u32 portid, int event, struct netlink_ext_ack *extack)
1998 {
1999         int i, ret;
2000         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
2001         struct tc_action *act;
2002         size_t attr_size = 0;
2003         struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
2004
2005         ret = nla_parse_nested_deprecated(tb, TCA_ACT_MAX_PRIO, nla, NULL,
2006                                           extack);
2007         if (ret < 0)
2008                 return ret;
2009
2010         if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) {
2011                 if (tb[1])
2012                         return tca_action_flush(net, tb[1], n, portid, extack);
2013
2014                 NL_SET_ERR_MSG(extack, "Invalid netlink attributes while flushing TC action");
2015                 return -EINVAL;
2016         }
2017
2018         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
2019                 act = tcf_action_get_1(net, tb[i], n, portid, extack);
2020                 if (IS_ERR(act)) {
2021                         ret = PTR_ERR(act);
2022                         goto err;
2023                 }
2024                 attr_size += tcf_action_fill_size(act);
2025                 actions[i - 1] = act;
2026         }
2027
2028         attr_size = tcf_action_full_attrs_size(attr_size);
2029
2030         if (event == RTM_GETACTION)
2031                 ret = tcf_get_notify(net, portid, n, actions, event, extack);
2032         else { /* delete */
2033                 ret = tcf_del_notify(net, n, actions, portid, attr_size, extack);
2034                 if (ret)
2035                         goto err;
2036                 return 0;
2037         }
2038 err:
2039         tcf_action_put_many(actions);
2040         return ret;
2041 }
2042
2043 static struct sk_buff *tcf_add_notify_msg(struct net *net, struct nlmsghdr *n,
2044                                           struct tc_action *actions[],
2045                                           u32 portid, size_t attr_size,
2046                                           struct netlink_ext_ack *extack)
2047 {
2048         struct sk_buff *skb;
2049
2050         skb = alloc_skb(max(attr_size, NLMSG_GOODSIZE), GFP_KERNEL);
2051         if (!skb)
2052                 return ERR_PTR(-ENOBUFS);
2053
2054         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, n->nlmsg_flags,
2055                          RTM_NEWACTION, 0, 0, extack) <= 0) {
2056                 NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
2057                 kfree_skb(skb);
2058                 return ERR_PTR(-EINVAL);
2059         }
2060
2061         return skb;
2062 }
2063
2064 static int tcf_add_notify(struct net *net, struct nlmsghdr *n,
2065                           struct tc_action *actions[], u32 portid,
2066                           size_t attr_size, struct netlink_ext_ack *extack)
2067 {
2068         struct sk_buff *skb;
2069
2070         if (!rtnl_notify_needed(net, n->nlmsg_flags, RTNLGRP_TC)) {
2071                 skb = NULL;
2072         } else {
2073                 skb = tcf_add_notify_msg(net, n, actions, portid, attr_size,
2074                                          extack);
2075                 if (IS_ERR(skb))
2076                         return PTR_ERR(skb);
2077         }
2078
2079         return rtnetlink_maybe_send(skb, net, portid, RTNLGRP_TC,
2080                                     n->nlmsg_flags & NLM_F_ECHO);
2081 }
2082
2083 static int tcf_action_add(struct net *net, struct nlattr *nla,
2084                           struct nlmsghdr *n, u32 portid, u32 flags,
2085                           struct netlink_ext_ack *extack)
2086 {
2087         size_t attr_size = 0;
2088         int loop, ret;
2089         struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
2090         int init_res[TCA_ACT_MAX_PRIO] = {};
2091
2092         for (loop = 0; loop < 10; loop++) {
2093                 ret = tcf_action_init(net, NULL, nla, NULL, actions, init_res,
2094                                       &attr_size, flags, 0, extack);
2095                 if (ret != -EAGAIN)
2096                         break;
2097         }
2098
2099         if (ret < 0)
2100                 return ret;
2101
2102         ret = tcf_add_notify(net, n, actions, portid, attr_size, extack);
2103
2104         /* only put bound actions */
2105         tca_put_bound_many(actions, init_res);
2106
2107         return ret;
2108 }
2109
2110 static const struct nla_policy tcaa_policy[TCA_ROOT_MAX + 1] = {
2111         [TCA_ROOT_FLAGS] = NLA_POLICY_BITFIELD32(TCA_ACT_FLAG_LARGE_DUMP_ON |
2112                                                  TCA_ACT_FLAG_TERSE_DUMP),
2113         [TCA_ROOT_TIME_DELTA]      = { .type = NLA_U32 },
2114 };
2115
2116 static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n,
2117                          struct netlink_ext_ack *extack)
2118 {
2119         struct net *net = sock_net(skb->sk);
2120         struct nlattr *tca[TCA_ROOT_MAX + 1];
2121         u32 portid = NETLINK_CB(skb).portid;
2122         u32 flags = 0;
2123         int ret = 0;
2124
2125         if ((n->nlmsg_type != RTM_GETACTION) &&
2126             !netlink_capable(skb, CAP_NET_ADMIN))
2127                 return -EPERM;
2128
2129         ret = nlmsg_parse_deprecated(n, sizeof(struct tcamsg), tca,
2130                                      TCA_ROOT_MAX, NULL, extack);
2131         if (ret < 0)
2132                 return ret;
2133
2134         if (tca[TCA_ACT_TAB] == NULL) {
2135                 NL_SET_ERR_MSG(extack, "Netlink action attributes missing");
2136                 return -EINVAL;
2137         }
2138
2139         /* n->nlmsg_flags & NLM_F_CREATE */
2140         switch (n->nlmsg_type) {
2141         case RTM_NEWACTION:
2142                 /* we are going to assume all other flags
2143                  * imply create only if it doesn't exist
2144                  * Note that CREATE | EXCL implies that
2145                  * but since we want avoid ambiguity (eg when flags
2146                  * is zero) then just set this
2147                  */
2148                 if (n->nlmsg_flags & NLM_F_REPLACE)
2149                         flags = TCA_ACT_FLAGS_REPLACE;
2150                 ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, portid, flags,
2151                                      extack);
2152                 break;
2153         case RTM_DELACTION:
2154                 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
2155                                     portid, RTM_DELACTION, extack);
2156                 break;
2157         case RTM_GETACTION:
2158                 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
2159                                     portid, RTM_GETACTION, extack);
2160                 break;
2161         default:
2162                 BUG();
2163         }
2164
2165         return ret;
2166 }
2167
2168 static struct nlattr *find_dump_kind(struct nlattr **nla)
2169 {
2170         struct nlattr *tb1, *tb2[TCA_ACT_MAX + 1];
2171         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
2172         struct nlattr *kind;
2173
2174         tb1 = nla[TCA_ACT_TAB];
2175         if (tb1 == NULL)
2176                 return NULL;
2177
2178         if (nla_parse_deprecated(tb, TCA_ACT_MAX_PRIO, nla_data(tb1), NLMSG_ALIGN(nla_len(tb1)), NULL, NULL) < 0)
2179                 return NULL;
2180
2181         if (tb[1] == NULL)
2182                 return NULL;
2183         if (nla_parse_nested_deprecated(tb2, TCA_ACT_MAX, tb[1], tcf_action_policy, NULL) < 0)
2184                 return NULL;
2185         kind = tb2[TCA_ACT_KIND];
2186
2187         return kind;
2188 }
2189
2190 static int tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
2191 {
2192         struct net *net = sock_net(skb->sk);
2193         struct nlmsghdr *nlh;
2194         unsigned char *b = skb_tail_pointer(skb);
2195         struct nlattr *nest;
2196         struct tc_action_ops *a_o;
2197         int ret = 0;
2198         struct tcamsg *t = (struct tcamsg *) nlmsg_data(cb->nlh);
2199         struct nlattr *tb[TCA_ROOT_MAX + 1];
2200         struct nlattr *count_attr = NULL;
2201         unsigned long jiffy_since = 0;
2202         struct nlattr *kind = NULL;
2203         struct nla_bitfield32 bf;
2204         u32 msecs_since = 0;
2205         u32 act_count = 0;
2206
2207         ret = nlmsg_parse_deprecated(cb->nlh, sizeof(struct tcamsg), tb,
2208                                      TCA_ROOT_MAX, tcaa_policy, cb->extack);
2209         if (ret < 0)
2210                 return ret;
2211
2212         kind = find_dump_kind(tb);
2213         if (kind == NULL) {
2214                 pr_info("tc_dump_action: action bad kind\n");
2215                 return 0;
2216         }
2217
2218         a_o = tc_lookup_action(kind);
2219         if (a_o == NULL)
2220                 return 0;
2221
2222         cb->args[2] = 0;
2223         if (tb[TCA_ROOT_FLAGS]) {
2224                 bf = nla_get_bitfield32(tb[TCA_ROOT_FLAGS]);
2225                 cb->args[2] = bf.value;
2226         }
2227
2228         if (tb[TCA_ROOT_TIME_DELTA]) {
2229                 msecs_since = nla_get_u32(tb[TCA_ROOT_TIME_DELTA]);
2230         }
2231
2232         nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
2233                         cb->nlh->nlmsg_type, sizeof(*t), 0);
2234         if (!nlh)
2235                 goto out_module_put;
2236
2237         if (msecs_since)
2238                 jiffy_since = jiffies - msecs_to_jiffies(msecs_since);
2239
2240         t = nlmsg_data(nlh);
2241         t->tca_family = AF_UNSPEC;
2242         t->tca__pad1 = 0;
2243         t->tca__pad2 = 0;
2244         cb->args[3] = jiffy_since;
2245         count_attr = nla_reserve(skb, TCA_ROOT_COUNT, sizeof(u32));
2246         if (!count_attr)
2247                 goto out_module_put;
2248
2249         nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
2250         if (nest == NULL)
2251                 goto out_module_put;
2252
2253         ret = __tcf_generic_walker(net, skb, cb, RTM_GETACTION, a_o, NULL);
2254         if (ret < 0)
2255                 goto out_module_put;
2256
2257         if (ret > 0) {
2258                 nla_nest_end(skb, nest);
2259                 ret = skb->len;
2260                 act_count = cb->args[1];
2261                 memcpy(nla_data(count_attr), &act_count, sizeof(u32));
2262                 cb->args[1] = 0;
2263         } else
2264                 nlmsg_trim(skb, b);
2265
2266         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
2267         if (NETLINK_CB(cb->skb).portid && ret)
2268                 nlh->nlmsg_flags |= NLM_F_MULTI;
2269         module_put(a_o->owner);
2270         return skb->len;
2271
2272 out_module_put:
2273         module_put(a_o->owner);
2274         nlmsg_trim(skb, b);
2275         return skb->len;
2276 }
2277
2278 static const struct rtnl_msg_handler tc_action_rtnl_msg_handlers[] __initconst = {
2279         {.msgtype = RTM_NEWACTION, .doit = tc_ctl_action},
2280         {.msgtype = RTM_DELACTION, .doit = tc_ctl_action},
2281         {.msgtype = RTM_GETACTION, .doit = tc_ctl_action,
2282          .dumpit = tc_dump_action},
2283 };
2284
2285 static int __init tc_action_init(void)
2286 {
2287         rtnl_register_many(tc_action_rtnl_msg_handlers);
2288         return 0;
2289 }
2290
2291 subsys_initcall(tc_action_init);