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
  29DEFINE_STATIC_KEY_FALSE(tcf_frag_xmit_count);
  30EXPORT_SYMBOL_GPL(tcf_frag_xmit_count);
  31#endif
  32
  33int 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}
  42EXPORT_SYMBOL_GPL(tcf_dev_queue_xmit);
  43
  44static 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
  52static 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
  60static 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
  70int 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	}
 101end:
 102	return ret;
 103}
 104EXPORT_SYMBOL(tcf_action_check_ctrlact);
 105
 106struct 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}
 113EXPORT_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 */
 120static 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
 135static void offload_action_hw_count_set(struct tc_action *act,
 136					u32 hw_count)
 137{
 138	act->in_hw_count = hw_count;
 139}
 140
 141static void offload_action_hw_count_inc(struct tc_action *act,
 142					u32 hw_count)
 143{
 144	act->in_hw_count += hw_count;
 145}
 146
 147static 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
 154static 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
 162static bool tc_act_skip_hw(u32 flags)
 163{
 164	return (flags & TCA_ACT_FLAGS_SKIP_HW) ? true : false;
 165}
 166
 167static 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. */
 173static 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
 180static 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
 203static 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
 219static 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
 236static 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
 246static 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
 288fl_err:
 289	kfree(fl_action);
 290
 291	return err;
 292}
 293
 294/* offload the tc action after it is inserted */
 295static 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
 301int 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}
 327EXPORT_SYMBOL(tcf_action_update_hw_stats);
 328
 329static 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
 358static int tcf_action_offload_del(struct tc_action *action)
 359{
 360	return tcf_action_offload_del_ex(action, NULL, NULL);
 361}
 362
 363static 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
 373static 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
 393static 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
 420int 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}
 430EXPORT_SYMBOL(tcf_idr_release);
 431
 432static 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
 460static 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
 468static 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
 477static int
 478tcf_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
 502nla_put_failure:
 503	nlmsg_trim(skb, b);
 504	return -1;
 505}
 506
 507static int
 508tcf_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
 546nla_put_failure:
 547	nlmsg_trim(skb, b);
 548	return -1;
 549}
 550
 551static 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	}
 600done:
 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
 611nla_put_failure:
 612	nla_nest_cancel(skb, nest);
 613	goto done;
 614}
 615
 616static 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
 630static 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;
 674nla_put_failure:
 675	nla_nest_cancel(skb, nest);
 676	return ret;
 677}
 678
 679int 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}
 696EXPORT_SYMBOL(tcf_generic_walker);
 697
 698int 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}
 717EXPORT_SYMBOL(tcf_idr_search);
 718
 719static 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
 732static 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
 744static 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
 777int 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;
 823err4:
 824	free_percpu(p->cpu_qstats);
 825err3:
 826	free_percpu(p->cpu_bstats_hw);
 827err2:
 828	free_percpu(p->cpu_bstats);
 829err1:
 830	kfree(p);
 831	return err;
 832}
 833EXPORT_SYMBOL(tcf_idr_create);
 834
 835int 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}
 844EXPORT_SYMBOL(tcf_idr_create_from_flags);
 845
 846/* Cleanup idr index that was allocated but not initialized. */
 847
 848void 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}
 857EXPORT_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
 868int 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
 914new:
 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}
 930EXPORT_SYMBOL(tcf_idr_check_alloc);
 931
 932void tcf_idrinfo_destroy(const struct tc_action_ops *ops,
 933			 struct tcf_idrinfo *idrinfo)
 934{
 935	struct idr *idr = &idrinfo->action_idr;
 936	bool mutex_taken = false;
 937	struct tc_action *p;
 938	unsigned long id = 1;
 939	unsigned long tmp;
 940	int ret;
 941
 942	idr_for_each_entry_ul(idr, p, tmp, id) {
 943		if (IS_ERR(p))
 944			continue;
 945		if (tc_act_in_hw(p) && !mutex_taken) {
 946			rtnl_lock();
 947			mutex_taken = true;
 948		}
 949		ret = __tcf_idr_release(p, false, true);
 950		if (ret == ACT_P_DELETED)
 951			module_put(ops->owner);
 952		else if (ret < 0)
 953			return;
 954	}
 955	if (mutex_taken)
 956		rtnl_unlock();
 957	idr_destroy(&idrinfo->action_idr);
 958}
 959EXPORT_SYMBOL(tcf_idrinfo_destroy);
 960
 961static LIST_HEAD(act_base);
 962static DEFINE_RWLOCK(act_mod_lock);
 963/* since act ops id is stored in pernet subsystem list,
 964 * then there is no way to walk through only all the action
 965 * subsystem, so we keep tc action pernet ops id for
 966 * reoffload to walk through.
 967 */
 968static LIST_HEAD(act_pernet_id_list);
 969static DEFINE_MUTEX(act_id_mutex);
 970struct tc_act_pernet_id {
 971	struct list_head list;
 972	unsigned int id;
 973};
 974
 975static int tcf_pernet_add_id_list(unsigned int id)
 976{
 977	struct tc_act_pernet_id *id_ptr;
 978	int ret = 0;
 979
 980	mutex_lock(&act_id_mutex);
 981	list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
 982		if (id_ptr->id == id) {
 983			ret = -EEXIST;
 984			goto err_out;
 985		}
 986	}
 987
 988	id_ptr = kzalloc(sizeof(*id_ptr), GFP_KERNEL);
 989	if (!id_ptr) {
 990		ret = -ENOMEM;
 991		goto err_out;
 992	}
 993	id_ptr->id = id;
 994
 995	list_add_tail(&id_ptr->list, &act_pernet_id_list);
 996
 997err_out:
 998	mutex_unlock(&act_id_mutex);
 999	return ret;
1000}
1001
1002static void tcf_pernet_del_id_list(unsigned int id)
1003{
1004	struct tc_act_pernet_id *id_ptr;
1005
1006	mutex_lock(&act_id_mutex);
1007	list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
1008		if (id_ptr->id == id) {
1009			list_del(&id_ptr->list);
1010			kfree(id_ptr);
1011			break;
1012		}
1013	}
1014	mutex_unlock(&act_id_mutex);
1015}
1016
1017int tcf_register_action(struct tc_action_ops *act,
1018			struct pernet_operations *ops)
1019{
1020	struct tc_action_ops *a;
1021	int ret;
1022
1023	if (!act->act || !act->dump || !act->init)
1024		return -EINVAL;
1025
1026	/* We have to register pernet ops before making the action ops visible,
1027	 * otherwise tcf_action_init_1() could get a partially initialized
1028	 * netns.
1029	 */
1030	ret = register_pernet_subsys(ops);
1031	if (ret)
1032		return ret;
1033
1034	if (ops->id) {
1035		ret = tcf_pernet_add_id_list(*ops->id);
1036		if (ret)
1037			goto err_id;
1038	}
1039
1040	write_lock(&act_mod_lock);
1041	list_for_each_entry(a, &act_base, head) {
1042		if (act->id == a->id || (strcmp(act->kind, a->kind) == 0)) {
1043			ret = -EEXIST;
1044			goto err_out;
1045		}
1046	}
1047	list_add_tail(&act->head, &act_base);
1048	write_unlock(&act_mod_lock);
1049
1050	return 0;
1051
1052err_out:
1053	write_unlock(&act_mod_lock);
1054	if (ops->id)
1055		tcf_pernet_del_id_list(*ops->id);
1056err_id:
1057	unregister_pernet_subsys(ops);
1058	return ret;
1059}
1060EXPORT_SYMBOL(tcf_register_action);
1061
1062int tcf_unregister_action(struct tc_action_ops *act,
1063			  struct pernet_operations *ops)
1064{
1065	struct tc_action_ops *a;
1066	int err = -ENOENT;
1067
1068	write_lock(&act_mod_lock);
1069	list_for_each_entry(a, &act_base, head) {
1070		if (a == act) {
1071			list_del(&act->head);
1072			err = 0;
1073			break;
1074		}
1075	}
1076	write_unlock(&act_mod_lock);
1077	if (!err) {
1078		unregister_pernet_subsys(ops);
1079		if (ops->id)
1080			tcf_pernet_del_id_list(*ops->id);
1081	}
1082	return err;
1083}
1084EXPORT_SYMBOL(tcf_unregister_action);
1085
1086/* lookup by name */
1087static struct tc_action_ops *tc_lookup_action_n(char *kind)
1088{
1089	struct tc_action_ops *a, *res = NULL;
1090
1091	if (kind) {
1092		read_lock(&act_mod_lock);
1093		list_for_each_entry(a, &act_base, head) {
1094			if (strcmp(kind, a->kind) == 0) {
1095				if (try_module_get(a->owner))
1096					res = a;
1097				break;
1098			}
1099		}
1100		read_unlock(&act_mod_lock);
1101	}
1102	return res;
1103}
1104
1105/* lookup by nlattr */
1106static struct tc_action_ops *tc_lookup_action(struct nlattr *kind)
1107{
1108	struct tc_action_ops *a, *res = NULL;
1109
1110	if (kind) {
1111		read_lock(&act_mod_lock);
1112		list_for_each_entry(a, &act_base, head) {
1113			if (nla_strcmp(kind, a->kind) == 0) {
1114				if (try_module_get(a->owner))
1115					res = a;
1116				break;
1117			}
1118		}
1119		read_unlock(&act_mod_lock);
1120	}
1121	return res;
1122}
1123
1124/*TCA_ACT_MAX_PRIO is 32, there count up to 32 */
1125#define TCA_ACT_MAX_PRIO_MASK 0x1FF
1126int tcf_action_exec(struct sk_buff *skb, struct tc_action **actions,
1127		    int nr_actions, struct tcf_result *res)
1128{
1129	u32 jmp_prgcnt = 0;
1130	u32 jmp_ttl = TCA_ACT_MAX_PRIO; /*matches actions per filter */
1131	int i;
1132	int ret = TC_ACT_OK;
1133
1134	if (skb_skip_tc_classify(skb))
1135		return TC_ACT_OK;
1136
1137restart_act_graph:
1138	for (i = 0; i < nr_actions; i++) {
1139		const struct tc_action *a = actions[i];
1140		int repeat_ttl;
1141
1142		if (jmp_prgcnt > 0) {
1143			jmp_prgcnt -= 1;
1144			continue;
1145		}
1146
1147		if (tc_act_skip_sw(a->tcfa_flags))
1148			continue;
1149
1150		repeat_ttl = 32;
1151repeat:
1152		ret = tc_act(skb, a, res);
1153		if (unlikely(ret == TC_ACT_REPEAT)) {
1154			if (--repeat_ttl != 0)
1155				goto repeat;
1156			/* suspicious opcode, stop pipeline */
1157			net_warn_ratelimited("TC_ACT_REPEAT abuse ?\n");
1158			return TC_ACT_OK;
1159		}
1160		if (TC_ACT_EXT_CMP(ret, TC_ACT_JUMP)) {
1161			jmp_prgcnt = ret & TCA_ACT_MAX_PRIO_MASK;
1162			if (!jmp_prgcnt || (jmp_prgcnt > nr_actions)) {
1163				/* faulty opcode, stop pipeline */
1164				return TC_ACT_OK;
1165			} else {
1166				jmp_ttl -= 1;
1167				if (jmp_ttl > 0)
1168					goto restart_act_graph;
1169				else /* faulty graph, stop pipeline */
1170					return TC_ACT_OK;
1171			}
1172		} else if (TC_ACT_EXT_CMP(ret, TC_ACT_GOTO_CHAIN)) {
1173			if (unlikely(!rcu_access_pointer(a->goto_chain))) {
1174				tcf_set_drop_reason(skb,
1175						    SKB_DROP_REASON_TC_CHAIN_NOTFOUND);
1176				return TC_ACT_SHOT;
1177			}
1178			tcf_action_goto_chain_exec(a, res);
1179		}
1180
1181		if (ret != TC_ACT_PIPE)
1182			break;
1183	}
1184
1185	return ret;
1186}
1187EXPORT_SYMBOL(tcf_action_exec);
1188
1189int tcf_action_destroy(struct tc_action *actions[], int bind)
1190{
1191	const struct tc_action_ops *ops;
1192	struct tc_action *a;
1193	int ret = 0, i;
1194
1195	tcf_act_for_each_action(i, a, actions) {
1196		actions[i] = NULL;
1197		ops = a->ops;
1198		ret = __tcf_idr_release(a, bind, true);
1199		if (ret == ACT_P_DELETED)
1200			module_put(ops->owner);
1201		else if (ret < 0)
1202			return ret;
1203	}
1204	return ret;
1205}
1206
1207static int tcf_action_put(struct tc_action *p)
1208{
1209	return __tcf_action_put(p, false);
1210}
1211
1212static void tcf_action_put_many(struct tc_action *actions[])
1213{
1214	struct tc_action *a;
1215	int i;
1216
1217	tcf_act_for_each_action(i, a, actions) {
1218		const struct tc_action_ops *ops = a->ops;
1219		if (tcf_action_put(a))
1220			module_put(ops->owner);
1221	}
1222}
1223
1224static void tca_put_bound_many(struct tc_action *actions[], int init_res[])
1225{
1226	struct tc_action *a;
1227	int i;
1228
1229	tcf_act_for_each_action(i, a, actions) {
1230		const struct tc_action_ops *ops = a->ops;
1231
1232		if (init_res[i] == ACT_P_CREATED)
1233			continue;
1234
1235		if (tcf_action_put(a))
1236			module_put(ops->owner);
1237	}
1238}
1239
1240int
1241tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
1242{
1243	return a->ops->dump(skb, a, bind, ref);
1244}
1245
1246int tcf_action_dump(struct sk_buff *skb, struct tc_action *actions[],
1247		    int bind, int ref, bool terse)
1248{
1249	struct tc_action *a;
1250	int err = -EINVAL, i;
1251	struct nlattr *nest;
1252
1253	tcf_act_for_each_action(i, a, actions) {
1254		nest = nla_nest_start_noflag(skb, i + 1);
1255		if (nest == NULL)
1256			goto nla_put_failure;
1257		err = terse ? tcf_action_dump_terse(skb, a, false) :
1258			tcf_action_dump_1(skb, a, bind, ref);
1259		if (err < 0)
1260			goto errout;
1261		nla_nest_end(skb, nest);
1262	}
1263
1264	return 0;
1265
1266nla_put_failure:
1267	err = -EINVAL;
1268errout:
1269	nla_nest_cancel(skb, nest);
1270	return err;
1271}
1272
1273static struct tc_cookie *nla_memdup_cookie(struct nlattr **tb)
1274{
1275	struct tc_cookie *c = kzalloc(sizeof(*c), GFP_KERNEL);
1276	if (!c)
1277		return NULL;
1278
1279	c->data = nla_memdup(tb[TCA_ACT_COOKIE], GFP_KERNEL);
1280	if (!c->data) {
1281		kfree(c);
1282		return NULL;
1283	}
1284	c->len = nla_len(tb[TCA_ACT_COOKIE]);
1285
1286	return c;
1287}
1288
1289static u8 tcf_action_hw_stats_get(struct nlattr *hw_stats_attr)
1290{
1291	struct nla_bitfield32 hw_stats_bf;
1292
1293	/* If the user did not pass the attr, that means he does
1294	 * not care about the type. Return "any" in that case
1295	 * which is setting on all supported types.
1296	 */
1297	if (!hw_stats_attr)
1298		return TCA_ACT_HW_STATS_ANY;
1299	hw_stats_bf = nla_get_bitfield32(hw_stats_attr);
1300	return hw_stats_bf.value;
1301}
1302
1303static const struct nla_policy tcf_action_policy[TCA_ACT_MAX + 1] = {
1304	[TCA_ACT_KIND]		= { .type = NLA_STRING },
1305	[TCA_ACT_INDEX]		= { .type = NLA_U32 },
1306	[TCA_ACT_COOKIE]	= { .type = NLA_BINARY,
1307				    .len = TC_COOKIE_MAX_SIZE },
1308	[TCA_ACT_OPTIONS]	= { .type = NLA_NESTED },
1309	[TCA_ACT_FLAGS]		= NLA_POLICY_BITFIELD32(TCA_ACT_FLAGS_NO_PERCPU_STATS |
1310							TCA_ACT_FLAGS_SKIP_HW |
1311							TCA_ACT_FLAGS_SKIP_SW),
1312	[TCA_ACT_HW_STATS]	= NLA_POLICY_BITFIELD32(TCA_ACT_HW_STATS_ANY),
1313};
1314
1315void tcf_idr_insert_many(struct tc_action *actions[], int init_res[])
1316{
1317	struct tc_action *a;
1318	int i;
1319
1320	tcf_act_for_each_action(i, a, actions) {
1321		struct tcf_idrinfo *idrinfo;
1322
1323		if (init_res[i] == ACT_P_BOUND)
1324			continue;
1325
1326		idrinfo = a->idrinfo;
1327		mutex_lock(&idrinfo->lock);
1328		/* Replace ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */
1329		idr_replace(&idrinfo->action_idr, a, a->tcfa_index);
1330		mutex_unlock(&idrinfo->lock);
1331	}
1332}
1333
1334struct tc_action_ops *tc_action_load_ops(struct nlattr *nla, u32 flags,
1335					 struct netlink_ext_ack *extack)
1336{
1337	bool police = flags & TCA_ACT_FLAGS_POLICE;
1338	struct nlattr *tb[TCA_ACT_MAX + 1];
1339	struct tc_action_ops *a_o;
1340	char act_name[IFNAMSIZ];
1341	struct nlattr *kind;
1342	int err;
1343
1344	if (!police) {
1345		err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1346						  tcf_action_policy, extack);
1347		if (err < 0)
1348			return ERR_PTR(err);
1349		err = -EINVAL;
1350		kind = tb[TCA_ACT_KIND];
1351		if (!kind) {
1352			NL_SET_ERR_MSG(extack, "TC action kind must be specified");
1353			return ERR_PTR(err);
1354		}
1355		if (nla_strscpy(act_name, kind, IFNAMSIZ) < 0) {
1356			NL_SET_ERR_MSG(extack, "TC action name too long");
1357			return ERR_PTR(err);
1358		}
1359	} else {
1360		if (strscpy(act_name, "police", IFNAMSIZ) < 0) {
1361			NL_SET_ERR_MSG(extack, "TC action name too long");
1362			return ERR_PTR(-EINVAL);
1363		}
1364	}
1365
1366	a_o = tc_lookup_action_n(act_name);
1367	if (a_o == NULL) {
1368#ifdef CONFIG_MODULES
1369		bool rtnl_held = !(flags & TCA_ACT_FLAGS_NO_RTNL);
1370
1371		if (rtnl_held)
1372			rtnl_unlock();
1373		request_module(NET_ACT_ALIAS_PREFIX "%s", act_name);
1374		if (rtnl_held)
1375			rtnl_lock();
1376
1377		a_o = tc_lookup_action_n(act_name);
1378
1379		/* We dropped the RTNL semaphore in order to
1380		 * perform the module load.  So, even if we
1381		 * succeeded in loading the module we have to
1382		 * tell the caller to replay the request.  We
1383		 * indicate this using -EAGAIN.
1384		 */
1385		if (a_o != NULL) {
1386			module_put(a_o->owner);
1387			return ERR_PTR(-EAGAIN);
1388		}
1389#endif
1390		NL_SET_ERR_MSG(extack, "Failed to load TC action module");
1391		return ERR_PTR(-ENOENT);
1392	}
1393
1394	return a_o;
1395}
1396
1397struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
1398				    struct nlattr *nla, struct nlattr *est,
1399				    struct tc_action_ops *a_o, int *init_res,
1400				    u32 flags, struct netlink_ext_ack *extack)
1401{
1402	bool police = flags & TCA_ACT_FLAGS_POLICE;
1403	struct nla_bitfield32 userflags = { 0, 0 };
1404	struct tc_cookie *user_cookie = NULL;
1405	u8 hw_stats = TCA_ACT_HW_STATS_ANY;
1406	struct nlattr *tb[TCA_ACT_MAX + 1];
1407	struct tc_action *a;
1408	int err;
1409
1410	/* backward compatibility for policer */
1411	if (!police) {
1412		err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1413						  tcf_action_policy, extack);
1414		if (err < 0)
1415			return ERR_PTR(err);
1416		if (tb[TCA_ACT_COOKIE]) {
1417			user_cookie = nla_memdup_cookie(tb);
1418			if (!user_cookie) {
1419				NL_SET_ERR_MSG(extack, "No memory to generate TC cookie");
1420				err = -ENOMEM;
1421				goto err_out;
1422			}
1423		}
1424		hw_stats = tcf_action_hw_stats_get(tb[TCA_ACT_HW_STATS]);
1425		if (tb[TCA_ACT_FLAGS]) {
1426			userflags = nla_get_bitfield32(tb[TCA_ACT_FLAGS]);
1427			if (!tc_act_flags_valid(userflags.value)) {
1428				err = -EINVAL;
1429				goto err_out;
1430			}
1431		}
1432
1433		err = a_o->init(net, tb[TCA_ACT_OPTIONS], est, &a, tp,
1434				userflags.value | flags, extack);
1435	} else {
1436		err = a_o->init(net, nla, est, &a, tp, userflags.value | flags,
1437				extack);
1438	}
1439	if (err < 0)
1440		goto err_out;
1441	*init_res = err;
1442
1443	if (!police && tb[TCA_ACT_COOKIE])
1444		tcf_set_action_cookie(&a->user_cookie, user_cookie);
1445
1446	if (!police)
1447		a->hw_stats = hw_stats;
1448
1449	return a;
1450
1451err_out:
1452	if (user_cookie) {
1453		kfree(user_cookie->data);
1454		kfree(user_cookie);
1455	}
1456	return ERR_PTR(err);
1457}
1458
1459static bool tc_act_bind(u32 flags)
1460{
1461	return !!(flags & TCA_ACT_FLAGS_BIND);
1462}
1463
1464/* Returns numbers of initialized actions or negative error. */
1465
1466int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla,
1467		    struct nlattr *est, struct tc_action *actions[],
1468		    int init_res[], size_t *attr_size,
1469		    u32 flags, u32 fl_flags,
1470		    struct netlink_ext_ack *extack)
1471{
1472	struct tc_action_ops *ops[TCA_ACT_MAX_PRIO] = {};
1473	struct nlattr *tb[TCA_ACT_MAX_PRIO + 2];
1474	struct tc_action *act;
1475	size_t sz = 0;
1476	int err;
1477	int i;
1478
1479	err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX_PRIO + 1, nla, NULL,
1480					  extack);
1481	if (err < 0)
1482		return err;
1483
1484	/* The nested attributes are parsed as types, but they are really an
1485	 * array of actions. So we parse one more than we can handle, and return
1486	 * an error if the last one is set (as that indicates that the request
1487	 * contained more than the maximum number of actions).
1488	 */
1489	if (tb[TCA_ACT_MAX_PRIO + 1]) {
1490		NL_SET_ERR_MSG_FMT(extack,
1491				   "Only %d actions supported per filter",
1492				   TCA_ACT_MAX_PRIO);
1493		return -EINVAL;
1494	}
1495
1496	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1497		struct tc_action_ops *a_o;
1498
1499		a_o = tc_action_load_ops(tb[i], flags, extack);
1500		if (IS_ERR(a_o)) {
1501			err = PTR_ERR(a_o);
1502			goto err_mod;
1503		}
1504		ops[i - 1] = a_o;
1505	}
1506
1507	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1508		act = tcf_action_init_1(net, tp, tb[i], est, ops[i - 1],
1509					&init_res[i - 1], flags, extack);
1510		if (IS_ERR(act)) {
1511			err = PTR_ERR(act);
1512			goto err;
1513		}
1514		sz += tcf_action_fill_size(act);
1515		/* Start from index 0 */
1516		actions[i - 1] = act;
1517		if (tc_act_bind(flags)) {
1518			bool skip_sw = tc_skip_sw(fl_flags);
1519			bool skip_hw = tc_skip_hw(fl_flags);
1520
1521			if (tc_act_bind(act->tcfa_flags)) {
1522				/* Action is created by classifier and is not
1523				 * standalone. Check that the user did not set
1524				 * any action flags different than the
1525				 * classifier flags, and inherit the flags from
1526				 * the classifier for the compatibility case
1527				 * where no flags were specified at all.
1528				 */
1529				if ((tc_act_skip_sw(act->tcfa_flags) && !skip_sw) ||
1530				    (tc_act_skip_hw(act->tcfa_flags) && !skip_hw)) {
1531					NL_SET_ERR_MSG(extack,
1532						       "Mismatch between action and filter offload flags");
1533					err = -EINVAL;
1534					goto err;
1535				}
1536				if (skip_sw)
1537					act->tcfa_flags |= TCA_ACT_FLAGS_SKIP_SW;
1538				if (skip_hw)
1539					act->tcfa_flags |= TCA_ACT_FLAGS_SKIP_HW;
1540				continue;
1541			}
1542
1543			/* Action is standalone */
1544			if (skip_sw != tc_act_skip_sw(act->tcfa_flags) ||
1545			    skip_hw != tc_act_skip_hw(act->tcfa_flags)) {
1546				NL_SET_ERR_MSG(extack,
1547					       "Mismatch between action and filter offload flags");
1548				err = -EINVAL;
1549				goto err;
1550			}
1551		} else {
1552			err = tcf_action_offload_add(act, extack);
1553			if (tc_act_skip_sw(act->tcfa_flags) && err)
1554				goto err;
1555		}
1556	}
1557
1558	/* We have to commit them all together, because if any error happened in
1559	 * between, we could not handle the failure gracefully.
1560	 */
1561	tcf_idr_insert_many(actions, init_res);
1562
1563	*attr_size = tcf_action_full_attrs_size(sz);
1564	err = i - 1;
1565	goto err_mod;
1566
1567err:
1568	tcf_action_destroy(actions, flags & TCA_ACT_FLAGS_BIND);
1569err_mod:
1570	for (i = 0; i < TCA_ACT_MAX_PRIO && ops[i]; i++)
1571		module_put(ops[i]->owner);
1572	return err;
1573}
1574
1575void tcf_action_update_stats(struct tc_action *a, u64 bytes, u64 packets,
1576			     u64 drops, bool hw)
1577{
1578	if (a->cpu_bstats) {
1579		_bstats_update(this_cpu_ptr(a->cpu_bstats), bytes, packets);
1580
1581		this_cpu_ptr(a->cpu_qstats)->drops += drops;
1582
1583		if (hw)
1584			_bstats_update(this_cpu_ptr(a->cpu_bstats_hw),
1585				       bytes, packets);
1586		return;
1587	}
1588
1589	_bstats_update(&a->tcfa_bstats, bytes, packets);
1590	atomic_add(drops, &a->tcfa_drops);
1591	if (hw)
1592		_bstats_update(&a->tcfa_bstats_hw, bytes, packets);
1593}
1594EXPORT_SYMBOL(tcf_action_update_stats);
1595
1596int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *p,
1597			  int compat_mode)
1598{
1599	struct gnet_stats_queue qstats = {0};
1600	struct gnet_dump d;
1601	int err = 0;
1602
1603	if (p == NULL)
1604		goto errout;
1605
1606	/* compat_mode being true specifies a call that is supposed
1607	 * to add additional backward compatibility statistic TLVs.
1608	 */
1609	if (compat_mode) {
1610		if (p->type == TCA_OLD_COMPAT)
1611			err = gnet_stats_start_copy_compat(skb, 0,
1612							   TCA_STATS,
1613							   TCA_XSTATS,
1614							   &p->tcfa_lock, &d,
1615							   TCA_PAD);
1616		else
1617			return 0;
1618	} else
1619		err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
1620					    &p->tcfa_lock, &d, TCA_ACT_PAD);
1621
1622	if (err < 0)
1623		goto errout;
1624
1625	qstats.drops = atomic_read(&p->tcfa_drops);
1626	qstats.overlimits = atomic_read(&p->tcfa_overlimits);
1627
1628	if (gnet_stats_copy_basic(&d, p->cpu_bstats,
1629				  &p->tcfa_bstats, false) < 0 ||
1630	    gnet_stats_copy_basic_hw(&d, p->cpu_bstats_hw,
1631				     &p->tcfa_bstats_hw, false) < 0 ||
1632	    gnet_stats_copy_rate_est(&d, &p->tcfa_rate_est) < 0 ||
1633	    gnet_stats_copy_queue(&d, p->cpu_qstats,
1634				  &qstats,
1635				  qstats.qlen) < 0)
1636		goto errout;
1637
1638	if (gnet_stats_finish_copy(&d) < 0)
1639		goto errout;
1640
1641	return 0;
1642
1643errout:
1644	return -1;
1645}
1646
1647static int tca_get_fill(struct sk_buff *skb, struct tc_action *actions[],
1648			u32 portid, u32 seq, u16 flags, int event, int bind,
1649			int ref, struct netlink_ext_ack *extack)
1650{
1651	struct tcamsg *t;
1652	struct nlmsghdr *nlh;
1653	unsigned char *b = skb_tail_pointer(skb);
1654	struct nlattr *nest;
1655
1656	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*t), flags);
1657	if (!nlh)
1658		goto out_nlmsg_trim;
1659	t = nlmsg_data(nlh);
1660	t->tca_family = AF_UNSPEC;
1661	t->tca__pad1 = 0;
1662	t->tca__pad2 = 0;
1663
1664	if (extack && extack->_msg &&
1665	    nla_put_string(skb, TCA_ROOT_EXT_WARN_MSG, extack->_msg))
1666		goto out_nlmsg_trim;
1667
1668	nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
1669	if (!nest)
1670		goto out_nlmsg_trim;
1671
1672	if (tcf_action_dump(skb, actions, bind, ref, false) < 0)
1673		goto out_nlmsg_trim;
1674
1675	nla_nest_end(skb, nest);
1676
1677	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1678
1679	return skb->len;
1680
1681out_nlmsg_trim:
1682	nlmsg_trim(skb, b);
1683	return -1;
1684}
1685
1686static int
1687tcf_get_notify(struct net *net, u32 portid, struct nlmsghdr *n,
1688	       struct tc_action *actions[], int event,
1689	       struct netlink_ext_ack *extack)
1690{
1691	struct sk_buff *skb;
1692
1693	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1694	if (!skb)
1695		return -ENOBUFS;
1696	if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, event,
1697			 0, 1, NULL) <= 0) {
1698		NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1699		kfree_skb(skb);
1700		return -EINVAL;
1701	}
1702
1703	return rtnl_unicast(skb, net, portid);
1704}
1705
1706static struct tc_action *tcf_action_get_1(struct net *net, struct nlattr *nla,
1707					  struct nlmsghdr *n, u32 portid,
1708					  struct netlink_ext_ack *extack)
1709{
1710	struct nlattr *tb[TCA_ACT_MAX + 1];
1711	const struct tc_action_ops *ops;
1712	struct tc_action *a;
1713	int index;
1714	int err;
1715
1716	err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1717					  tcf_action_policy, extack);
1718	if (err < 0)
1719		goto err_out;
1720
1721	err = -EINVAL;
1722	if (tb[TCA_ACT_INDEX] == NULL ||
1723	    nla_len(tb[TCA_ACT_INDEX]) < sizeof(index)) {
1724		NL_SET_ERR_MSG(extack, "Invalid TC action index value");
1725		goto err_out;
1726	}
1727	index = nla_get_u32(tb[TCA_ACT_INDEX]);
1728
1729	err = -EINVAL;
1730	ops = tc_lookup_action(tb[TCA_ACT_KIND]);
1731	if (!ops) { /* could happen in batch of actions */
1732		NL_SET_ERR_MSG(extack, "Specified TC action kind not found");
1733		goto err_out;
1734	}
1735	err = -ENOENT;
1736	if (__tcf_idr_search(net, ops, &a, index) == 0) {
1737		NL_SET_ERR_MSG(extack, "TC action with specified index not found");
1738		goto err_mod;
1739	}
1740
1741	module_put(ops->owner);
1742	return a;
1743
1744err_mod:
1745	module_put(ops->owner);
1746err_out:
1747	return ERR_PTR(err);
1748}
1749
1750static int tca_action_flush(struct net *net, struct nlattr *nla,
1751			    struct nlmsghdr *n, u32 portid,
1752			    struct netlink_ext_ack *extack)
1753{
1754	struct sk_buff *skb;
1755	unsigned char *b;
1756	struct nlmsghdr *nlh;
1757	struct tcamsg *t;
1758	struct netlink_callback dcb;
1759	struct nlattr *nest;
1760	struct nlattr *tb[TCA_ACT_MAX + 1];
1761	const struct tc_action_ops *ops;
1762	struct nlattr *kind;
1763	int err = -ENOMEM;
1764
1765	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1766	if (!skb)
1767		return err;
1768
1769	b = skb_tail_pointer(skb);
1770
1771	err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1772					  tcf_action_policy, extack);
1773	if (err < 0)
1774		goto err_out;
1775
1776	err = -EINVAL;
1777	kind = tb[TCA_ACT_KIND];
1778	ops = tc_lookup_action(kind);
1779	if (!ops) { /*some idjot trying to flush unknown action */
1780		NL_SET_ERR_MSG(extack, "Cannot flush unknown TC action");
1781		goto err_out;
1782	}
1783
1784	nlh = nlmsg_put(skb, portid, n->nlmsg_seq, RTM_DELACTION,
1785			sizeof(*t), 0);
1786	if (!nlh) {
1787		NL_SET_ERR_MSG(extack, "Failed to create TC action flush notification");
1788		goto out_module_put;
1789	}
1790	t = nlmsg_data(nlh);
1791	t->tca_family = AF_UNSPEC;
1792	t->tca__pad1 = 0;
1793	t->tca__pad2 = 0;
1794
1795	nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
1796	if (!nest) {
1797		NL_SET_ERR_MSG(extack, "Failed to add new netlink message");
1798		goto out_module_put;
1799	}
1800
1801	err = __tcf_generic_walker(net, skb, &dcb, RTM_DELACTION, ops, extack);
1802	if (err <= 0) {
1803		nla_nest_cancel(skb, nest);
1804		goto out_module_put;
1805	}
1806
1807	nla_nest_end(skb, nest);
1808
1809	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1810	nlh->nlmsg_flags |= NLM_F_ROOT;
1811	module_put(ops->owner);
1812	err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1813			     n->nlmsg_flags & NLM_F_ECHO);
1814	if (err < 0)
1815		NL_SET_ERR_MSG(extack, "Failed to send TC action flush notification");
1816
1817	return err;
1818
1819out_module_put:
1820	module_put(ops->owner);
1821err_out:
1822	kfree_skb(skb);
1823	return err;
1824}
1825
1826static int tcf_action_delete(struct net *net, struct tc_action *actions[])
1827{
1828	struct tc_action *a;
1829	int i;
1830
1831	tcf_act_for_each_action(i, a, actions) {
1832		const struct tc_action_ops *ops = a->ops;
1833		/* Actions can be deleted concurrently so we must save their
1834		 * type and id to search again after reference is released.
1835		 */
1836		struct tcf_idrinfo *idrinfo = a->idrinfo;
1837		u32 act_index = a->tcfa_index;
1838
1839		actions[i] = NULL;
1840		if (tcf_action_put(a)) {
1841			/* last reference, action was deleted concurrently */
1842			module_put(ops->owner);
1843		} else {
1844			int ret;
1845
1846			/* now do the delete */
1847			ret = tcf_idr_delete_index(idrinfo, act_index);
1848			if (ret < 0)
1849				return ret;
1850		}
1851	}
1852	return 0;
1853}
1854
1855static struct sk_buff *tcf_reoffload_del_notify_msg(struct net *net,
1856						    struct tc_action *action)
1857{
1858	size_t attr_size = tcf_action_fill_size(action);
1859	struct tc_action *actions[TCA_ACT_MAX_PRIO] = {
1860		[0] = action,
1861	};
1862	struct sk_buff *skb;
1863
1864	skb = alloc_skb(max(attr_size, NLMSG_GOODSIZE), GFP_KERNEL);
1865	if (!skb)
1866		return ERR_PTR(-ENOBUFS);
1867
1868	if (tca_get_fill(skb, actions, 0, 0, 0, RTM_DELACTION, 0, 1, NULL) <= 0) {
1869		kfree_skb(skb);
1870		return ERR_PTR(-EINVAL);
1871	}
1872
1873	return skb;
1874}
1875
1876static int tcf_reoffload_del_notify(struct net *net, struct tc_action *action)
1877{
1878	const struct tc_action_ops *ops = action->ops;
1879	struct sk_buff *skb;
1880	int ret;
1881
1882	if (!rtnl_notify_needed(net, 0, RTNLGRP_TC)) {
1883		skb = NULL;
1884	} else {
1885		skb = tcf_reoffload_del_notify_msg(net, action);
1886		if (IS_ERR(skb))
1887			return PTR_ERR(skb);
1888	}
1889
1890	ret = tcf_idr_release_unsafe(action);
1891	if (ret == ACT_P_DELETED) {
1892		module_put(ops->owner);
1893		ret = rtnetlink_maybe_send(skb, net, 0, RTNLGRP_TC, 0);
1894	} else {
1895		kfree_skb(skb);
1896	}
1897
1898	return ret;
1899}
1900
1901int tcf_action_reoffload_cb(flow_indr_block_bind_cb_t *cb,
1902			    void *cb_priv, bool add)
1903{
1904	struct tc_act_pernet_id *id_ptr;
1905	struct tcf_idrinfo *idrinfo;
1906	struct tc_action_net *tn;
1907	struct tc_action *p;
1908	unsigned int act_id;
1909	unsigned long tmp;
1910	unsigned long id;
1911	struct idr *idr;
1912	struct net *net;
1913	int ret;
1914
1915	if (!cb)
1916		return -EINVAL;
1917
1918	down_read(&net_rwsem);
1919	mutex_lock(&act_id_mutex);
1920
1921	for_each_net(net) {
1922		list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
1923			act_id = id_ptr->id;
1924			tn = net_generic(net, act_id);
1925			if (!tn)
1926				continue;
1927			idrinfo = tn->idrinfo;
1928			if (!idrinfo)
1929				continue;
1930
1931			mutex_lock(&idrinfo->lock);
1932			idr = &idrinfo->action_idr;
1933			idr_for_each_entry_ul(idr, p, tmp, id) {
1934				if (IS_ERR(p) || tc_act_bind(p->tcfa_flags))
1935					continue;
1936				if (add) {
1937					tcf_action_offload_add_ex(p, NULL, cb,
1938								  cb_priv);
1939					continue;
1940				}
1941
1942				/* cb unregister to update hw count */
1943				ret = tcf_action_offload_del_ex(p, cb, cb_priv);
1944				if (ret < 0)
1945					continue;
1946				if (tc_act_skip_sw(p->tcfa_flags) &&
1947				    !tc_act_in_hw(p))
1948					tcf_reoffload_del_notify(net, p);
1949			}
1950			mutex_unlock(&idrinfo->lock);
1951		}
1952	}
1953	mutex_unlock(&act_id_mutex);
1954	up_read(&net_rwsem);
1955
1956	return 0;
1957}
1958
1959static struct sk_buff *tcf_del_notify_msg(struct net *net, struct nlmsghdr *n,
1960					  struct tc_action *actions[],
1961					  u32 portid, size_t attr_size,
1962					  struct netlink_ext_ack *extack)
1963{
1964	struct sk_buff *skb;
1965
1966	skb = alloc_skb(max(attr_size, NLMSG_GOODSIZE), GFP_KERNEL);
1967	if (!skb)
1968		return ERR_PTR(-ENOBUFS);
1969
1970	if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, RTM_DELACTION,
1971			 0, 2, extack) <= 0) {
1972		NL_SET_ERR_MSG(extack, "Failed to fill netlink TC action attributes");
1973		kfree_skb(skb);
1974		return ERR_PTR(-EINVAL);
1975	}
1976
1977	return skb;
1978}
1979
1980static int tcf_del_notify(struct net *net, struct nlmsghdr *n,
1981			  struct tc_action *actions[], u32 portid,
1982			  size_t attr_size, struct netlink_ext_ack *extack)
1983{
1984	struct sk_buff *skb;
1985	int ret;
1986
1987	if (!rtnl_notify_needed(net, n->nlmsg_flags, RTNLGRP_TC)) {
1988		skb = NULL;
1989	} else {
1990		skb = tcf_del_notify_msg(net, n, actions, portid, attr_size,
1991					 extack);
1992		if (IS_ERR(skb))
1993			return PTR_ERR(skb);
1994	}
1995
1996	/* now do the delete */
1997	ret = tcf_action_delete(net, actions);
1998	if (ret < 0) {
1999		NL_SET_ERR_MSG(extack, "Failed to delete TC action");
2000		kfree_skb(skb);
2001		return ret;
2002	}
2003
2004	return rtnetlink_maybe_send(skb, net, portid, RTNLGRP_TC,
2005				    n->nlmsg_flags & NLM_F_ECHO);
2006}
2007
2008static int
2009tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
2010	      u32 portid, int event, struct netlink_ext_ack *extack)
2011{
2012	int i, ret;
2013	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
2014	struct tc_action *act;
2015	size_t attr_size = 0;
2016	struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
2017
2018	ret = nla_parse_nested_deprecated(tb, TCA_ACT_MAX_PRIO, nla, NULL,
2019					  extack);
2020	if (ret < 0)
2021		return ret;
2022
2023	if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) {
2024		if (tb[1])
2025			return tca_action_flush(net, tb[1], n, portid, extack);
2026
2027		NL_SET_ERR_MSG(extack, "Invalid netlink attributes while flushing TC action");
2028		return -EINVAL;
2029	}
2030
2031	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
2032		act = tcf_action_get_1(net, tb[i], n, portid, extack);
2033		if (IS_ERR(act)) {
2034			ret = PTR_ERR(act);
2035			goto err;
2036		}
2037		attr_size += tcf_action_fill_size(act);
2038		actions[i - 1] = act;
2039	}
2040
2041	attr_size = tcf_action_full_attrs_size(attr_size);
2042
2043	if (event == RTM_GETACTION)
2044		ret = tcf_get_notify(net, portid, n, actions, event, extack);
2045	else { /* delete */
2046		ret = tcf_del_notify(net, n, actions, portid, attr_size, extack);
2047		if (ret)
2048			goto err;
2049		return 0;
2050	}
2051err:
2052	tcf_action_put_many(actions);
2053	return ret;
2054}
2055
2056static struct sk_buff *tcf_add_notify_msg(struct net *net, struct nlmsghdr *n,
2057					  struct tc_action *actions[],
2058					  u32 portid, size_t attr_size,
2059					  struct netlink_ext_ack *extack)
2060{
2061	struct sk_buff *skb;
2062
2063	skb = alloc_skb(max(attr_size, NLMSG_GOODSIZE), GFP_KERNEL);
2064	if (!skb)
2065		return ERR_PTR(-ENOBUFS);
2066
2067	if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, n->nlmsg_flags,
2068			 RTM_NEWACTION, 0, 0, extack) <= 0) {
2069		NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
2070		kfree_skb(skb);
2071		return ERR_PTR(-EINVAL);
2072	}
2073
2074	return skb;
2075}
2076
2077static int tcf_add_notify(struct net *net, struct nlmsghdr *n,
2078			  struct tc_action *actions[], u32 portid,
2079			  size_t attr_size, struct netlink_ext_ack *extack)
2080{
2081	struct sk_buff *skb;
2082
2083	if (!rtnl_notify_needed(net, n->nlmsg_flags, RTNLGRP_TC)) {
2084		skb = NULL;
2085	} else {
2086		skb = tcf_add_notify_msg(net, n, actions, portid, attr_size,
2087					 extack);
2088		if (IS_ERR(skb))
2089			return PTR_ERR(skb);
2090	}
2091
2092	return rtnetlink_maybe_send(skb, net, portid, RTNLGRP_TC,
2093				    n->nlmsg_flags & NLM_F_ECHO);
2094}
2095
2096static int tcf_action_add(struct net *net, struct nlattr *nla,
2097			  struct nlmsghdr *n, u32 portid, u32 flags,
2098			  struct netlink_ext_ack *extack)
2099{
2100	size_t attr_size = 0;
2101	int loop, ret;
2102	struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
2103	int init_res[TCA_ACT_MAX_PRIO] = {};
2104
2105	for (loop = 0; loop < 10; loop++) {
2106		ret = tcf_action_init(net, NULL, nla, NULL, actions, init_res,
2107				      &attr_size, flags, 0, extack);
2108		if (ret != -EAGAIN)
2109			break;
2110	}
2111
2112	if (ret < 0)
2113		return ret;
2114
2115	ret = tcf_add_notify(net, n, actions, portid, attr_size, extack);
2116
2117	/* only put bound actions */
2118	tca_put_bound_many(actions, init_res);
2119
2120	return ret;
2121}
2122
2123static const struct nla_policy tcaa_policy[TCA_ROOT_MAX + 1] = {
2124	[TCA_ROOT_FLAGS] = NLA_POLICY_BITFIELD32(TCA_ACT_FLAG_LARGE_DUMP_ON |
2125						 TCA_ACT_FLAG_TERSE_DUMP),
2126	[TCA_ROOT_TIME_DELTA]      = { .type = NLA_U32 },
2127};
2128
2129static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n,
2130			 struct netlink_ext_ack *extack)
2131{
2132	struct net *net = sock_net(skb->sk);
2133	struct nlattr *tca[TCA_ROOT_MAX + 1];
2134	u32 portid = NETLINK_CB(skb).portid;
2135	u32 flags = 0;
2136	int ret = 0;
2137
2138	if ((n->nlmsg_type != RTM_GETACTION) &&
2139	    !netlink_capable(skb, CAP_NET_ADMIN))
2140		return -EPERM;
2141
2142	ret = nlmsg_parse_deprecated(n, sizeof(struct tcamsg), tca,
2143				     TCA_ROOT_MAX, NULL, extack);
2144	if (ret < 0)
2145		return ret;
2146
2147	if (tca[TCA_ACT_TAB] == NULL) {
2148		NL_SET_ERR_MSG(extack, "Netlink action attributes missing");
2149		return -EINVAL;
2150	}
2151
2152	/* n->nlmsg_flags & NLM_F_CREATE */
2153	switch (n->nlmsg_type) {
2154	case RTM_NEWACTION:
2155		/* we are going to assume all other flags
2156		 * imply create only if it doesn't exist
2157		 * Note that CREATE | EXCL implies that
2158		 * but since we want avoid ambiguity (eg when flags
2159		 * is zero) then just set this
2160		 */
2161		if (n->nlmsg_flags & NLM_F_REPLACE)
2162			flags = TCA_ACT_FLAGS_REPLACE;
2163		ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, portid, flags,
2164				     extack);
2165		break;
2166	case RTM_DELACTION:
2167		ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
2168				    portid, RTM_DELACTION, extack);
2169		break;
2170	case RTM_GETACTION:
2171		ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
2172				    portid, RTM_GETACTION, extack);
2173		break;
2174	default:
2175		BUG();
2176	}
2177
2178	return ret;
2179}
2180
2181static struct nlattr *find_dump_kind(struct nlattr **nla)
2182{
2183	struct nlattr *tb1, *tb2[TCA_ACT_MAX + 1];
2184	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
2185	struct nlattr *kind;
2186
2187	tb1 = nla[TCA_ACT_TAB];
2188	if (tb1 == NULL)
2189		return NULL;
2190
2191	if (nla_parse_deprecated(tb, TCA_ACT_MAX_PRIO, nla_data(tb1), NLMSG_ALIGN(nla_len(tb1)), NULL, NULL) < 0)
2192		return NULL;
2193
2194	if (tb[1] == NULL)
2195		return NULL;
2196	if (nla_parse_nested_deprecated(tb2, TCA_ACT_MAX, tb[1], tcf_action_policy, NULL) < 0)
2197		return NULL;
2198	kind = tb2[TCA_ACT_KIND];
2199
2200	return kind;
2201}
2202
2203static int tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
2204{
2205	struct net *net = sock_net(skb->sk);
2206	struct nlmsghdr *nlh;
2207	unsigned char *b = skb_tail_pointer(skb);
2208	struct nlattr *nest;
2209	struct tc_action_ops *a_o;
2210	int ret = 0;
2211	struct tcamsg *t = (struct tcamsg *) nlmsg_data(cb->nlh);
2212	struct nlattr *tb[TCA_ROOT_MAX + 1];
2213	struct nlattr *count_attr = NULL;
2214	unsigned long jiffy_since = 0;
2215	struct nlattr *kind = NULL;
2216	struct nla_bitfield32 bf;
2217	u32 msecs_since = 0;
2218	u32 act_count = 0;
2219
2220	ret = nlmsg_parse_deprecated(cb->nlh, sizeof(struct tcamsg), tb,
2221				     TCA_ROOT_MAX, tcaa_policy, cb->extack);
2222	if (ret < 0)
2223		return ret;
2224
2225	kind = find_dump_kind(tb);
2226	if (kind == NULL) {
2227		pr_info("tc_dump_action: action bad kind\n");
2228		return 0;
2229	}
2230
2231	a_o = tc_lookup_action(kind);
2232	if (a_o == NULL)
2233		return 0;
2234
2235	cb->args[2] = 0;
2236	if (tb[TCA_ROOT_FLAGS]) {
2237		bf = nla_get_bitfield32(tb[TCA_ROOT_FLAGS]);
2238		cb->args[2] = bf.value;
2239	}
2240
2241	if (tb[TCA_ROOT_TIME_DELTA]) {
2242		msecs_since = nla_get_u32(tb[TCA_ROOT_TIME_DELTA]);
2243	}
2244
2245	nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
2246			cb->nlh->nlmsg_type, sizeof(*t), 0);
2247	if (!nlh)
2248		goto out_module_put;
2249
2250	if (msecs_since)
2251		jiffy_since = jiffies - msecs_to_jiffies(msecs_since);
2252
2253	t = nlmsg_data(nlh);
2254	t->tca_family = AF_UNSPEC;
2255	t->tca__pad1 = 0;
2256	t->tca__pad2 = 0;
2257	cb->args[3] = jiffy_since;
2258	count_attr = nla_reserve(skb, TCA_ROOT_COUNT, sizeof(u32));
2259	if (!count_attr)
2260		goto out_module_put;
2261
2262	nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
2263	if (nest == NULL)
2264		goto out_module_put;
2265
2266	ret = __tcf_generic_walker(net, skb, cb, RTM_GETACTION, a_o, NULL);
2267	if (ret < 0)
2268		goto out_module_put;
2269
2270	if (ret > 0) {
2271		nla_nest_end(skb, nest);
2272		ret = skb->len;
2273		act_count = cb->args[1];
2274		memcpy(nla_data(count_attr), &act_count, sizeof(u32));
2275		cb->args[1] = 0;
2276	} else
2277		nlmsg_trim(skb, b);
2278
2279	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
2280	if (NETLINK_CB(cb->skb).portid && ret)
2281		nlh->nlmsg_flags |= NLM_F_MULTI;
2282	module_put(a_o->owner);
2283	return skb->len;
2284
2285out_module_put:
2286	module_put(a_o->owner);
2287	nlmsg_trim(skb, b);
2288	return skb->len;
2289}
2290
2291static const struct rtnl_msg_handler tc_action_rtnl_msg_handlers[] __initconst = {
2292	{.msgtype = RTM_NEWACTION, .doit = tc_ctl_action},
2293	{.msgtype = RTM_DELACTION, .doit = tc_ctl_action},
2294	{.msgtype = RTM_GETACTION, .doit = tc_ctl_action,
2295	 .dumpit = tc_dump_action},
2296};
2297
2298static int __init tc_action_init(void)
2299{
2300	rtnl_register_many(tc_action_rtnl_msg_handlers);
2301	return 0;
2302}
2303
2304subsys_initcall(tc_action_init);