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v5.9
   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/act_api.h>
  23#include <net/netlink.h>
  24
  25static void tcf_action_goto_chain_exec(const struct tc_action *a,
  26				       struct tcf_result *res)
  27{
  28	const struct tcf_chain *chain = rcu_dereference_bh(a->goto_chain);
  29
  30	res->goto_tp = rcu_dereference_bh(chain->filter_chain);
  31}
  32
  33static void tcf_free_cookie_rcu(struct rcu_head *p)
  34{
  35	struct tc_cookie *cookie = container_of(p, struct tc_cookie, rcu);
  36
  37	kfree(cookie->data);
  38	kfree(cookie);
  39}
  40
  41static void tcf_set_action_cookie(struct tc_cookie __rcu **old_cookie,
  42				  struct tc_cookie *new_cookie)
  43{
  44	struct tc_cookie *old;
  45
  46	old = xchg((__force struct tc_cookie **)old_cookie, new_cookie);
  47	if (old)
  48		call_rcu(&old->rcu, tcf_free_cookie_rcu);
  49}
  50
  51int tcf_action_check_ctrlact(int action, struct tcf_proto *tp,
  52			     struct tcf_chain **newchain,
  53			     struct netlink_ext_ack *extack)
  54{
  55	int opcode = TC_ACT_EXT_OPCODE(action), ret = -EINVAL;
  56	u32 chain_index;
  57
  58	if (!opcode)
  59		ret = action > TC_ACT_VALUE_MAX ? -EINVAL : 0;
  60	else if (opcode <= TC_ACT_EXT_OPCODE_MAX || action == TC_ACT_UNSPEC)
  61		ret = 0;
  62	if (ret) {
  63		NL_SET_ERR_MSG(extack, "invalid control action");
  64		goto end;
  65	}
  66
  67	if (TC_ACT_EXT_CMP(action, TC_ACT_GOTO_CHAIN)) {
  68		chain_index = action & TC_ACT_EXT_VAL_MASK;
  69		if (!tp || !newchain) {
  70			ret = -EINVAL;
  71			NL_SET_ERR_MSG(extack,
  72				       "can't goto NULL proto/chain");
  73			goto end;
  74		}
  75		*newchain = tcf_chain_get_by_act(tp->chain->block, chain_index);
  76		if (!*newchain) {
  77			ret = -ENOMEM;
  78			NL_SET_ERR_MSG(extack,
  79				       "can't allocate goto_chain");
  80		}
  81	}
  82end:
  83	return ret;
  84}
  85EXPORT_SYMBOL(tcf_action_check_ctrlact);
  86
  87struct tcf_chain *tcf_action_set_ctrlact(struct tc_action *a, int action,
  88					 struct tcf_chain *goto_chain)
  89{
  90	a->tcfa_action = action;
  91	goto_chain = rcu_replace_pointer(a->goto_chain, goto_chain, 1);
  92	return goto_chain;
  93}
  94EXPORT_SYMBOL(tcf_action_set_ctrlact);
  95
  96/* XXX: For standalone actions, we don't need a RCU grace period either, because
  97 * actions are always connected to filters and filters are already destroyed in
  98 * RCU callbacks, so after a RCU grace period actions are already disconnected
  99 * from filters. Readers later can not find us.
 100 */
 101static void free_tcf(struct tc_action *p)
 102{
 103	struct tcf_chain *chain = rcu_dereference_protected(p->goto_chain, 1);
 104
 105	free_percpu(p->cpu_bstats);
 106	free_percpu(p->cpu_bstats_hw);
 107	free_percpu(p->cpu_qstats);
 108
 109	tcf_set_action_cookie(&p->act_cookie, NULL);
 110	if (chain)
 111		tcf_chain_put_by_act(chain);
 112
 113	kfree(p);
 114}
 115
 116static void tcf_action_cleanup(struct tc_action *p)
 117{
 118	if (p->ops->cleanup)
 119		p->ops->cleanup(p);
 120
 121	gen_kill_estimator(&p->tcfa_rate_est);
 122	free_tcf(p);
 123}
 124
 125static int __tcf_action_put(struct tc_action *p, bool bind)
 126{
 127	struct tcf_idrinfo *idrinfo = p->idrinfo;
 128
 129	if (refcount_dec_and_mutex_lock(&p->tcfa_refcnt, &idrinfo->lock)) {
 130		if (bind)
 131			atomic_dec(&p->tcfa_bindcnt);
 132		idr_remove(&idrinfo->action_idr, p->tcfa_index);
 133		mutex_unlock(&idrinfo->lock);
 134
 135		tcf_action_cleanup(p);
 136		return 1;
 137	}
 138
 139	if (bind)
 140		atomic_dec(&p->tcfa_bindcnt);
 141
 142	return 0;
 143}
 144
 145int __tcf_idr_release(struct tc_action *p, bool bind, bool strict)
 146{
 147	int ret = 0;
 148
 149	/* Release with strict==1 and bind==0 is only called through act API
 150	 * interface (classifiers always bind). Only case when action with
 151	 * positive reference count and zero bind count can exist is when it was
 152	 * also created with act API (unbinding last classifier will destroy the
 153	 * action if it was created by classifier). So only case when bind count
 154	 * can be changed after initial check is when unbound action is
 155	 * destroyed by act API while classifier binds to action with same id
 156	 * concurrently. This result either creation of new action(same behavior
 157	 * as before), or reusing existing action if concurrent process
 158	 * increments reference count before action is deleted. Both scenarios
 159	 * are acceptable.
 160	 */
 161	if (p) {
 162		if (!bind && strict && atomic_read(&p->tcfa_bindcnt) > 0)
 163			return -EPERM;
 164
 165		if (__tcf_action_put(p, bind))
 166			ret = ACT_P_DELETED;
 167	}
 168
 169	return ret;
 170}
 171EXPORT_SYMBOL(__tcf_idr_release);
 172
 173static size_t tcf_action_shared_attrs_size(const struct tc_action *act)
 174{
 175	struct tc_cookie *act_cookie;
 176	u32 cookie_len = 0;
 177
 178	rcu_read_lock();
 179	act_cookie = rcu_dereference(act->act_cookie);
 180
 181	if (act_cookie)
 182		cookie_len = nla_total_size(act_cookie->len);
 183	rcu_read_unlock();
 184
 185	return  nla_total_size(0) /* action number nested */
 186		+ nla_total_size(IFNAMSIZ) /* TCA_ACT_KIND */
 187		+ cookie_len /* TCA_ACT_COOKIE */
 188		+ nla_total_size(sizeof(struct nla_bitfield32)) /* TCA_ACT_HW_STATS */
 189		+ nla_total_size(0) /* TCA_ACT_STATS nested */
 190		+ nla_total_size(sizeof(struct nla_bitfield32)) /* TCA_ACT_FLAGS */
 191		/* TCA_STATS_BASIC */
 192		+ nla_total_size_64bit(sizeof(struct gnet_stats_basic))
 193		/* TCA_STATS_PKT64 */
 194		+ nla_total_size_64bit(sizeof(u64))
 195		/* TCA_STATS_QUEUE */
 196		+ nla_total_size_64bit(sizeof(struct gnet_stats_queue))
 197		+ nla_total_size(0) /* TCA_OPTIONS nested */
 198		+ nla_total_size(sizeof(struct tcf_t)); /* TCA_GACT_TM */
 199}
 200
 201static size_t tcf_action_full_attrs_size(size_t sz)
 202{
 203	return NLMSG_HDRLEN                     /* struct nlmsghdr */
 204		+ sizeof(struct tcamsg)
 205		+ nla_total_size(0)             /* TCA_ACT_TAB nested */
 206		+ sz;
 207}
 208
 209static size_t tcf_action_fill_size(const struct tc_action *act)
 210{
 211	size_t sz = tcf_action_shared_attrs_size(act);
 212
 213	if (act->ops->get_fill_size)
 214		return act->ops->get_fill_size(act) + sz;
 215	return sz;
 216}
 217
 218static int tcf_dump_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb,
 219			   struct netlink_callback *cb)
 220{
 221	int err = 0, index = -1, s_i = 0, n_i = 0;
 222	u32 act_flags = cb->args[2];
 223	unsigned long jiffy_since = cb->args[3];
 224	struct nlattr *nest;
 225	struct idr *idr = &idrinfo->action_idr;
 226	struct tc_action *p;
 227	unsigned long id = 1;
 228	unsigned long tmp;
 229
 230	mutex_lock(&idrinfo->lock);
 231
 232	s_i = cb->args[0];
 233
 234	idr_for_each_entry_ul(idr, p, tmp, id) {
 235		index++;
 236		if (index < s_i)
 237			continue;
 238		if (IS_ERR(p))
 239			continue;
 240
 241		if (jiffy_since &&
 242		    time_after(jiffy_since,
 243			       (unsigned long)p->tcfa_tm.lastuse))
 244			continue;
 245
 246		nest = nla_nest_start_noflag(skb, n_i);
 247		if (!nest) {
 248			index--;
 249			goto nla_put_failure;
 250		}
 251		err = tcf_action_dump_1(skb, p, 0, 0);
 252		if (err < 0) {
 253			index--;
 254			nlmsg_trim(skb, nest);
 255			goto done;
 256		}
 257		nla_nest_end(skb, nest);
 258		n_i++;
 259		if (!(act_flags & TCA_FLAG_LARGE_DUMP_ON) &&
 260		    n_i >= TCA_ACT_MAX_PRIO)
 261			goto done;
 262	}
 263done:
 264	if (index >= 0)
 265		cb->args[0] = index + 1;
 266
 267	mutex_unlock(&idrinfo->lock);
 268	if (n_i) {
 269		if (act_flags & TCA_FLAG_LARGE_DUMP_ON)
 270			cb->args[1] = n_i;
 271	}
 272	return n_i;
 273
 274nla_put_failure:
 275	nla_nest_cancel(skb, nest);
 276	goto done;
 277}
 278
 279static int tcf_idr_release_unsafe(struct tc_action *p)
 280{
 281	if (atomic_read(&p->tcfa_bindcnt) > 0)
 282		return -EPERM;
 283
 284	if (refcount_dec_and_test(&p->tcfa_refcnt)) {
 285		idr_remove(&p->idrinfo->action_idr, p->tcfa_index);
 286		tcf_action_cleanup(p);
 287		return ACT_P_DELETED;
 288	}
 289
 290	return 0;
 291}
 292
 293static int tcf_del_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb,
 294			  const struct tc_action_ops *ops)
 295{
 296	struct nlattr *nest;
 297	int n_i = 0;
 298	int ret = -EINVAL;
 299	struct idr *idr = &idrinfo->action_idr;
 300	struct tc_action *p;
 301	unsigned long id = 1;
 302	unsigned long tmp;
 303
 304	nest = nla_nest_start_noflag(skb, 0);
 305	if (nest == NULL)
 306		goto nla_put_failure;
 307	if (nla_put_string(skb, TCA_KIND, ops->kind))
 308		goto nla_put_failure;
 309
 310	mutex_lock(&idrinfo->lock);
 311	idr_for_each_entry_ul(idr, p, tmp, id) {
 312		if (IS_ERR(p))
 313			continue;
 314		ret = tcf_idr_release_unsafe(p);
 315		if (ret == ACT_P_DELETED) {
 316			module_put(ops->owner);
 317			n_i++;
 318		} else if (ret < 0) {
 319			mutex_unlock(&idrinfo->lock);
 320			goto nla_put_failure;
 321		}
 322	}
 323	mutex_unlock(&idrinfo->lock);
 324
 325	if (nla_put_u32(skb, TCA_FCNT, n_i))
 326		goto nla_put_failure;
 327	nla_nest_end(skb, nest);
 328
 329	return n_i;
 330nla_put_failure:
 331	nla_nest_cancel(skb, nest);
 332	return ret;
 333}
 334
 335int tcf_generic_walker(struct tc_action_net *tn, struct sk_buff *skb,
 336		       struct netlink_callback *cb, int type,
 337		       const struct tc_action_ops *ops,
 338		       struct netlink_ext_ack *extack)
 339{
 340	struct tcf_idrinfo *idrinfo = tn->idrinfo;
 341
 342	if (type == RTM_DELACTION) {
 343		return tcf_del_walker(idrinfo, skb, ops);
 344	} else if (type == RTM_GETACTION) {
 345		return tcf_dump_walker(idrinfo, skb, cb);
 346	} else {
 347		WARN(1, "tcf_generic_walker: unknown command %d\n", type);
 348		NL_SET_ERR_MSG(extack, "tcf_generic_walker: unknown command");
 349		return -EINVAL;
 350	}
 351}
 352EXPORT_SYMBOL(tcf_generic_walker);
 353
 354int tcf_idr_search(struct tc_action_net *tn, struct tc_action **a, u32 index)
 355{
 356	struct tcf_idrinfo *idrinfo = tn->idrinfo;
 357	struct tc_action *p;
 358
 359	mutex_lock(&idrinfo->lock);
 360	p = idr_find(&idrinfo->action_idr, index);
 361	if (IS_ERR(p))
 362		p = NULL;
 363	else if (p)
 364		refcount_inc(&p->tcfa_refcnt);
 365	mutex_unlock(&idrinfo->lock);
 366
 367	if (p) {
 368		*a = p;
 369		return true;
 370	}
 371	return false;
 372}
 373EXPORT_SYMBOL(tcf_idr_search);
 374
 375static int tcf_idr_delete_index(struct tcf_idrinfo *idrinfo, u32 index)
 376{
 377	struct tc_action *p;
 378	int ret = 0;
 379
 380	mutex_lock(&idrinfo->lock);
 381	p = idr_find(&idrinfo->action_idr, index);
 382	if (!p) {
 383		mutex_unlock(&idrinfo->lock);
 384		return -ENOENT;
 385	}
 386
 387	if (!atomic_read(&p->tcfa_bindcnt)) {
 388		if (refcount_dec_and_test(&p->tcfa_refcnt)) {
 389			struct module *owner = p->ops->owner;
 390
 391			WARN_ON(p != idr_remove(&idrinfo->action_idr,
 392						p->tcfa_index));
 393			mutex_unlock(&idrinfo->lock);
 394
 395			tcf_action_cleanup(p);
 396			module_put(owner);
 397			return 0;
 398		}
 399		ret = 0;
 400	} else {
 401		ret = -EPERM;
 402	}
 403
 404	mutex_unlock(&idrinfo->lock);
 405	return ret;
 406}
 407
 408int tcf_idr_create(struct tc_action_net *tn, u32 index, struct nlattr *est,
 409		   struct tc_action **a, const struct tc_action_ops *ops,
 410		   int bind, bool cpustats, u32 flags)
 411{
 412	struct tc_action *p = kzalloc(ops->size, GFP_KERNEL);
 413	struct tcf_idrinfo *idrinfo = tn->idrinfo;
 414	int err = -ENOMEM;
 415
 416	if (unlikely(!p))
 417		return -ENOMEM;
 418	refcount_set(&p->tcfa_refcnt, 1);
 419	if (bind)
 420		atomic_set(&p->tcfa_bindcnt, 1);
 421
 422	if (cpustats) {
 423		p->cpu_bstats = netdev_alloc_pcpu_stats(struct gnet_stats_basic_cpu);
 424		if (!p->cpu_bstats)
 425			goto err1;
 426		p->cpu_bstats_hw = netdev_alloc_pcpu_stats(struct gnet_stats_basic_cpu);
 427		if (!p->cpu_bstats_hw)
 428			goto err2;
 429		p->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
 430		if (!p->cpu_qstats)
 431			goto err3;
 432	}
 433	spin_lock_init(&p->tcfa_lock);
 434	p->tcfa_index = index;
 435	p->tcfa_tm.install = jiffies;
 436	p->tcfa_tm.lastuse = jiffies;
 437	p->tcfa_tm.firstuse = 0;
 438	p->tcfa_flags = flags;
 439	if (est) {
 440		err = gen_new_estimator(&p->tcfa_bstats, p->cpu_bstats,
 441					&p->tcfa_rate_est,
 442					&p->tcfa_lock, NULL, est);
 443		if (err)
 444			goto err4;
 445	}
 446
 447	p->idrinfo = idrinfo;
 448	p->ops = ops;
 449	*a = p;
 450	return 0;
 451err4:
 452	free_percpu(p->cpu_qstats);
 453err3:
 454	free_percpu(p->cpu_bstats_hw);
 455err2:
 456	free_percpu(p->cpu_bstats);
 457err1:
 458	kfree(p);
 459	return err;
 460}
 461EXPORT_SYMBOL(tcf_idr_create);
 462
 463int tcf_idr_create_from_flags(struct tc_action_net *tn, u32 index,
 464			      struct nlattr *est, struct tc_action **a,
 465			      const struct tc_action_ops *ops, int bind,
 466			      u32 flags)
 467{
 468	/* Set cpustats according to actions flags. */
 469	return tcf_idr_create(tn, index, est, a, ops, bind,
 470			      !(flags & TCA_ACT_FLAGS_NO_PERCPU_STATS), flags);
 471}
 472EXPORT_SYMBOL(tcf_idr_create_from_flags);
 473
 474/* Cleanup idr index that was allocated but not initialized. */
 475
 476void tcf_idr_cleanup(struct tc_action_net *tn, u32 index)
 477{
 478	struct tcf_idrinfo *idrinfo = tn->idrinfo;
 479
 480	mutex_lock(&idrinfo->lock);
 481	/* Remove ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */
 482	WARN_ON(!IS_ERR(idr_remove(&idrinfo->action_idr, index)));
 483	mutex_unlock(&idrinfo->lock);
 484}
 485EXPORT_SYMBOL(tcf_idr_cleanup);
 486
 487/* Check if action with specified index exists. If actions is found, increments
 488 * its reference and bind counters, and return 1. Otherwise insert temporary
 489 * error pointer (to prevent concurrent users from inserting actions with same
 490 * index) and return 0.
 491 */
 492
 493int tcf_idr_check_alloc(struct tc_action_net *tn, u32 *index,
 494			struct tc_action **a, int bind)
 495{
 496	struct tcf_idrinfo *idrinfo = tn->idrinfo;
 497	struct tc_action *p;
 498	int ret;
 499
 500again:
 501	mutex_lock(&idrinfo->lock);
 502	if (*index) {
 503		p = idr_find(&idrinfo->action_idr, *index);
 504		if (IS_ERR(p)) {
 505			/* This means that another process allocated
 506			 * index but did not assign the pointer yet.
 507			 */
 508			mutex_unlock(&idrinfo->lock);
 509			goto again;
 510		}
 511
 512		if (p) {
 513			refcount_inc(&p->tcfa_refcnt);
 514			if (bind)
 515				atomic_inc(&p->tcfa_bindcnt);
 516			*a = p;
 517			ret = 1;
 518		} else {
 519			*a = NULL;
 520			ret = idr_alloc_u32(&idrinfo->action_idr, NULL, index,
 521					    *index, GFP_KERNEL);
 522			if (!ret)
 523				idr_replace(&idrinfo->action_idr,
 524					    ERR_PTR(-EBUSY), *index);
 525		}
 526	} else {
 527		*index = 1;
 528		*a = NULL;
 529		ret = idr_alloc_u32(&idrinfo->action_idr, NULL, index,
 530				    UINT_MAX, GFP_KERNEL);
 531		if (!ret)
 532			idr_replace(&idrinfo->action_idr, ERR_PTR(-EBUSY),
 533				    *index);
 534	}
 535	mutex_unlock(&idrinfo->lock);
 536	return ret;
 537}
 538EXPORT_SYMBOL(tcf_idr_check_alloc);
 539
 540void tcf_idrinfo_destroy(const struct tc_action_ops *ops,
 541			 struct tcf_idrinfo *idrinfo)
 542{
 543	struct idr *idr = &idrinfo->action_idr;
 544	struct tc_action *p;
 545	int ret;
 546	unsigned long id = 1;
 547	unsigned long tmp;
 548
 549	idr_for_each_entry_ul(idr, p, tmp, id) {
 550		ret = __tcf_idr_release(p, false, true);
 551		if (ret == ACT_P_DELETED)
 552			module_put(ops->owner);
 553		else if (ret < 0)
 554			return;
 555	}
 556	idr_destroy(&idrinfo->action_idr);
 557}
 558EXPORT_SYMBOL(tcf_idrinfo_destroy);
 559
 560static LIST_HEAD(act_base);
 561static DEFINE_RWLOCK(act_mod_lock);
 562
 563int tcf_register_action(struct tc_action_ops *act,
 564			struct pernet_operations *ops)
 565{
 566	struct tc_action_ops *a;
 567	int ret;
 568
 569	if (!act->act || !act->dump || !act->init || !act->walk || !act->lookup)
 570		return -EINVAL;
 571
 572	/* We have to register pernet ops before making the action ops visible,
 573	 * otherwise tcf_action_init_1() could get a partially initialized
 574	 * netns.
 575	 */
 576	ret = register_pernet_subsys(ops);
 577	if (ret)
 578		return ret;
 579
 580	write_lock(&act_mod_lock);
 581	list_for_each_entry(a, &act_base, head) {
 582		if (act->id == a->id || (strcmp(act->kind, a->kind) == 0)) {
 583			write_unlock(&act_mod_lock);
 584			unregister_pernet_subsys(ops);
 585			return -EEXIST;
 586		}
 587	}
 588	list_add_tail(&act->head, &act_base);
 589	write_unlock(&act_mod_lock);
 590
 591	return 0;
 592}
 593EXPORT_SYMBOL(tcf_register_action);
 594
 595int tcf_unregister_action(struct tc_action_ops *act,
 596			  struct pernet_operations *ops)
 597{
 598	struct tc_action_ops *a;
 599	int err = -ENOENT;
 600
 601	write_lock(&act_mod_lock);
 602	list_for_each_entry(a, &act_base, head) {
 603		if (a == act) {
 604			list_del(&act->head);
 605			err = 0;
 606			break;
 607		}
 608	}
 609	write_unlock(&act_mod_lock);
 610	if (!err)
 611		unregister_pernet_subsys(ops);
 612	return err;
 613}
 614EXPORT_SYMBOL(tcf_unregister_action);
 615
 616/* lookup by name */
 617static struct tc_action_ops *tc_lookup_action_n(char *kind)
 618{
 619	struct tc_action_ops *a, *res = NULL;
 620
 621	if (kind) {
 622		read_lock(&act_mod_lock);
 623		list_for_each_entry(a, &act_base, head) {
 624			if (strcmp(kind, a->kind) == 0) {
 625				if (try_module_get(a->owner))
 626					res = a;
 627				break;
 628			}
 629		}
 630		read_unlock(&act_mod_lock);
 631	}
 632	return res;
 633}
 634
 635/* lookup by nlattr */
 636static struct tc_action_ops *tc_lookup_action(struct nlattr *kind)
 637{
 638	struct tc_action_ops *a, *res = NULL;
 639
 640	if (kind) {
 641		read_lock(&act_mod_lock);
 642		list_for_each_entry(a, &act_base, head) {
 643			if (nla_strcmp(kind, a->kind) == 0) {
 644				if (try_module_get(a->owner))
 645					res = a;
 646				break;
 647			}
 648		}
 649		read_unlock(&act_mod_lock);
 650	}
 651	return res;
 652}
 653
 654/*TCA_ACT_MAX_PRIO is 32, there count upto 32 */
 655#define TCA_ACT_MAX_PRIO_MASK 0x1FF
 656int tcf_action_exec(struct sk_buff *skb, struct tc_action **actions,
 657		    int nr_actions, struct tcf_result *res)
 658{
 659	u32 jmp_prgcnt = 0;
 660	u32 jmp_ttl = TCA_ACT_MAX_PRIO; /*matches actions per filter */
 661	int i;
 662	int ret = TC_ACT_OK;
 663
 664	if (skb_skip_tc_classify(skb))
 665		return TC_ACT_OK;
 666
 667restart_act_graph:
 668	for (i = 0; i < nr_actions; i++) {
 669		const struct tc_action *a = actions[i];
 670
 671		if (jmp_prgcnt > 0) {
 672			jmp_prgcnt -= 1;
 673			continue;
 674		}
 675repeat:
 676		ret = a->ops->act(skb, a, res);
 677		if (ret == TC_ACT_REPEAT)
 678			goto repeat;	/* we need a ttl - JHS */
 679
 680		if (TC_ACT_EXT_CMP(ret, TC_ACT_JUMP)) {
 681			jmp_prgcnt = ret & TCA_ACT_MAX_PRIO_MASK;
 682			if (!jmp_prgcnt || (jmp_prgcnt > nr_actions)) {
 683				/* faulty opcode, stop pipeline */
 684				return TC_ACT_OK;
 685			} else {
 686				jmp_ttl -= 1;
 687				if (jmp_ttl > 0)
 688					goto restart_act_graph;
 689				else /* faulty graph, stop pipeline */
 690					return TC_ACT_OK;
 691			}
 692		} else if (TC_ACT_EXT_CMP(ret, TC_ACT_GOTO_CHAIN)) {
 693			if (unlikely(!rcu_access_pointer(a->goto_chain))) {
 694				net_warn_ratelimited("can't go to NULL chain!\n");
 695				return TC_ACT_SHOT;
 696			}
 697			tcf_action_goto_chain_exec(a, res);
 698		}
 699
 700		if (ret != TC_ACT_PIPE)
 701			break;
 702	}
 703
 704	return ret;
 705}
 706EXPORT_SYMBOL(tcf_action_exec);
 707
 708int tcf_action_destroy(struct tc_action *actions[], int bind)
 709{
 710	const struct tc_action_ops *ops;
 711	struct tc_action *a;
 712	int ret = 0, i;
 713
 714	for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
 715		a = actions[i];
 716		actions[i] = NULL;
 717		ops = a->ops;
 718		ret = __tcf_idr_release(a, bind, true);
 719		if (ret == ACT_P_DELETED)
 720			module_put(ops->owner);
 721		else if (ret < 0)
 722			return ret;
 723	}
 724	return ret;
 725}
 726
 
 
 
 
 
 
 
 727static int tcf_action_put(struct tc_action *p)
 728{
 729	return __tcf_action_put(p, false);
 730}
 731
 732/* Put all actions in this array, skip those NULL's. */
 733static void tcf_action_put_many(struct tc_action *actions[])
 734{
 735	int i;
 736
 737	for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
 738		struct tc_action *a = actions[i];
 739		const struct tc_action_ops *ops;
 740
 741		if (!a)
 742			continue;
 743		ops = a->ops;
 744		if (tcf_action_put(a))
 745			module_put(ops->owner);
 746	}
 747}
 748
 749int
 750tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 751{
 752	return a->ops->dump(skb, a, bind, ref);
 753}
 754
 755static int
 756tcf_action_dump_terse(struct sk_buff *skb, struct tc_action *a)
 757{
 
 758	unsigned char *b = skb_tail_pointer(skb);
 
 759	struct tc_cookie *cookie;
 760
 761	if (nla_put_string(skb, TCA_KIND, a->ops->kind))
 762		goto nla_put_failure;
 763	if (tcf_action_copy_stats(skb, a, 0))
 764		goto nla_put_failure;
 765
 766	rcu_read_lock();
 767	cookie = rcu_dereference(a->act_cookie);
 768	if (cookie) {
 769		if (nla_put(skb, TCA_ACT_COOKIE, cookie->len, cookie->data)) {
 770			rcu_read_unlock();
 771			goto nla_put_failure;
 772		}
 773	}
 774	rcu_read_unlock();
 775
 776	return 0;
 777
 778nla_put_failure:
 779	nlmsg_trim(skb, b);
 780	return -1;
 781}
 782
 783int
 784tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 785{
 786	int err = -EINVAL;
 787	unsigned char *b = skb_tail_pointer(skb);
 788	struct nlattr *nest;
 789
 790	if (tcf_action_dump_terse(skb, a))
 791		goto nla_put_failure;
 792
 793	if (a->hw_stats != TCA_ACT_HW_STATS_ANY &&
 794	    nla_put_bitfield32(skb, TCA_ACT_HW_STATS,
 795			       a->hw_stats, TCA_ACT_HW_STATS_ANY))
 796		goto nla_put_failure;
 797
 798	if (a->used_hw_stats_valid &&
 799	    nla_put_bitfield32(skb, TCA_ACT_USED_HW_STATS,
 800			       a->used_hw_stats, TCA_ACT_HW_STATS_ANY))
 801		goto nla_put_failure;
 802
 803	if (a->tcfa_flags &&
 804	    nla_put_bitfield32(skb, TCA_ACT_FLAGS,
 805			       a->tcfa_flags, a->tcfa_flags))
 806		goto nla_put_failure;
 807
 808	nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
 809	if (nest == NULL)
 810		goto nla_put_failure;
 811	err = tcf_action_dump_old(skb, a, bind, ref);
 812	if (err > 0) {
 813		nla_nest_end(skb, nest);
 814		return err;
 815	}
 816
 817nla_put_failure:
 818	nlmsg_trim(skb, b);
 819	return -1;
 820}
 821EXPORT_SYMBOL(tcf_action_dump_1);
 822
 823int tcf_action_dump(struct sk_buff *skb, struct tc_action *actions[],
 824		    int bind, int ref, bool terse)
 825{
 826	struct tc_action *a;
 827	int err = -EINVAL, i;
 828	struct nlattr *nest;
 829
 830	for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
 831		a = actions[i];
 832		nest = nla_nest_start_noflag(skb, i + 1);
 833		if (nest == NULL)
 834			goto nla_put_failure;
 835		err = terse ? tcf_action_dump_terse(skb, a) :
 836			tcf_action_dump_1(skb, a, bind, ref);
 837		if (err < 0)
 838			goto errout;
 839		nla_nest_end(skb, nest);
 840	}
 841
 842	return 0;
 843
 844nla_put_failure:
 845	err = -EINVAL;
 846errout:
 847	nla_nest_cancel(skb, nest);
 848	return err;
 849}
 850
 851static struct tc_cookie *nla_memdup_cookie(struct nlattr **tb)
 852{
 853	struct tc_cookie *c = kzalloc(sizeof(*c), GFP_KERNEL);
 854	if (!c)
 855		return NULL;
 856
 857	c->data = nla_memdup(tb[TCA_ACT_COOKIE], GFP_KERNEL);
 858	if (!c->data) {
 859		kfree(c);
 860		return NULL;
 861	}
 862	c->len = nla_len(tb[TCA_ACT_COOKIE]);
 863
 864	return c;
 865}
 866
 867static u8 tcf_action_hw_stats_get(struct nlattr *hw_stats_attr)
 868{
 869	struct nla_bitfield32 hw_stats_bf;
 870
 871	/* If the user did not pass the attr, that means he does
 872	 * not care about the type. Return "any" in that case
 873	 * which is setting on all supported types.
 874	 */
 875	if (!hw_stats_attr)
 876		return TCA_ACT_HW_STATS_ANY;
 877	hw_stats_bf = nla_get_bitfield32(hw_stats_attr);
 878	return hw_stats_bf.value;
 879}
 880
 881static const struct nla_policy tcf_action_policy[TCA_ACT_MAX + 1] = {
 882	[TCA_ACT_KIND]		= { .type = NLA_STRING },
 883	[TCA_ACT_INDEX]		= { .type = NLA_U32 },
 884	[TCA_ACT_COOKIE]	= { .type = NLA_BINARY,
 885				    .len = TC_COOKIE_MAX_SIZE },
 886	[TCA_ACT_OPTIONS]	= { .type = NLA_NESTED },
 887	[TCA_ACT_FLAGS]		= NLA_POLICY_BITFIELD32(TCA_ACT_FLAGS_NO_PERCPU_STATS),
 888	[TCA_ACT_HW_STATS]	= NLA_POLICY_BITFIELD32(TCA_ACT_HW_STATS_ANY),
 889};
 890
 891static void tcf_idr_insert_many(struct tc_action *actions[])
 892{
 893	int i;
 894
 895	for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
 896		struct tc_action *a = actions[i];
 897		struct tcf_idrinfo *idrinfo;
 898
 899		if (!a)
 900			continue;
 901		idrinfo = a->idrinfo;
 902		mutex_lock(&idrinfo->lock);
 903		/* Replace ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc if
 904		 * it is just created, otherwise this is just a nop.
 905		 */
 906		idr_replace(&idrinfo->action_idr, a, a->tcfa_index);
 907		mutex_unlock(&idrinfo->lock);
 908	}
 909}
 910
 911struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
 912				    struct nlattr *nla, struct nlattr *est,
 913				    char *name, int ovr, int bind,
 914				    bool rtnl_held,
 915				    struct netlink_ext_ack *extack)
 916{
 917	struct nla_bitfield32 flags = { 0, 0 };
 918	u8 hw_stats = TCA_ACT_HW_STATS_ANY;
 919	struct tc_action *a;
 920	struct tc_action_ops *a_o;
 921	struct tc_cookie *cookie = NULL;
 922	char act_name[IFNAMSIZ];
 923	struct nlattr *tb[TCA_ACT_MAX + 1];
 924	struct nlattr *kind;
 925	int err;
 926
 927	if (name == NULL) {
 928		err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
 929						  tcf_action_policy, extack);
 930		if (err < 0)
 931			goto err_out;
 932		err = -EINVAL;
 933		kind = tb[TCA_ACT_KIND];
 934		if (!kind) {
 935			NL_SET_ERR_MSG(extack, "TC action kind must be specified");
 936			goto err_out;
 937		}
 938		if (nla_strlcpy(act_name, kind, IFNAMSIZ) >= IFNAMSIZ) {
 939			NL_SET_ERR_MSG(extack, "TC action name too long");
 940			goto err_out;
 941		}
 942		if (tb[TCA_ACT_COOKIE]) {
 943			cookie = nla_memdup_cookie(tb);
 944			if (!cookie) {
 945				NL_SET_ERR_MSG(extack, "No memory to generate TC cookie");
 946				err = -ENOMEM;
 947				goto err_out;
 948			}
 949		}
 950		hw_stats = tcf_action_hw_stats_get(tb[TCA_ACT_HW_STATS]);
 951		if (tb[TCA_ACT_FLAGS])
 952			flags = nla_get_bitfield32(tb[TCA_ACT_FLAGS]);
 953	} else {
 954		if (strlcpy(act_name, name, IFNAMSIZ) >= IFNAMSIZ) {
 955			NL_SET_ERR_MSG(extack, "TC action name too long");
 956			err = -EINVAL;
 957			goto err_out;
 958		}
 959	}
 960
 961	a_o = tc_lookup_action_n(act_name);
 962	if (a_o == NULL) {
 963#ifdef CONFIG_MODULES
 964		if (rtnl_held)
 965			rtnl_unlock();
 966		request_module("act_%s", act_name);
 967		if (rtnl_held)
 968			rtnl_lock();
 969
 970		a_o = tc_lookup_action_n(act_name);
 971
 972		/* We dropped the RTNL semaphore in order to
 973		 * perform the module load.  So, even if we
 974		 * succeeded in loading the module we have to
 975		 * tell the caller to replay the request.  We
 976		 * indicate this using -EAGAIN.
 977		 */
 978		if (a_o != NULL) {
 979			err = -EAGAIN;
 980			goto err_mod;
 981		}
 982#endif
 983		NL_SET_ERR_MSG(extack, "Failed to load TC action module");
 984		err = -ENOENT;
 985		goto err_out;
 986	}
 987
 988	/* backward compatibility for policer */
 989	if (name == NULL)
 990		err = a_o->init(net, tb[TCA_ACT_OPTIONS], est, &a, ovr, bind,
 991				rtnl_held, tp, flags.value, extack);
 992	else
 993		err = a_o->init(net, nla, est, &a, ovr, bind, rtnl_held,
 994				tp, flags.value, extack);
 995	if (err < 0)
 996		goto err_mod;
 997
 998	if (!name && tb[TCA_ACT_COOKIE])
 999		tcf_set_action_cookie(&a->act_cookie, cookie);
1000
1001	if (!name)
1002		a->hw_stats = hw_stats;
1003
1004	/* module count goes up only when brand new policy is created
1005	 * if it exists and is only bound to in a_o->init() then
1006	 * ACT_P_CREATED is not returned (a zero is).
1007	 */
1008	if (err != ACT_P_CREATED)
1009		module_put(a_o->owner);
1010
 
 
 
 
 
 
 
1011	return a;
1012
1013err_mod:
1014	module_put(a_o->owner);
1015err_out:
1016	if (cookie) {
1017		kfree(cookie->data);
1018		kfree(cookie);
1019	}
1020	return ERR_PTR(err);
1021}
1022
1023/* Returns numbers of initialized actions or negative error. */
1024
1025int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla,
1026		    struct nlattr *est, char *name, int ovr, int bind,
1027		    struct tc_action *actions[], size_t *attr_size,
1028		    bool rtnl_held, struct netlink_ext_ack *extack)
1029{
1030	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1031	struct tc_action *act;
1032	size_t sz = 0;
1033	int err;
1034	int i;
1035
1036	err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX_PRIO, nla, NULL,
1037					  extack);
1038	if (err < 0)
1039		return err;
1040
1041	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1042		act = tcf_action_init_1(net, tp, tb[i], est, name, ovr, bind,
1043					rtnl_held, extack);
1044		if (IS_ERR(act)) {
1045			err = PTR_ERR(act);
1046			goto err;
1047		}
 
1048		sz += tcf_action_fill_size(act);
1049		/* Start from index 0 */
1050		actions[i - 1] = act;
1051	}
1052
1053	/* We have to commit them all together, because if any error happened in
1054	 * between, we could not handle the failure gracefully.
1055	 */
1056	tcf_idr_insert_many(actions);
1057
1058	*attr_size = tcf_action_full_attrs_size(sz);
1059	return i - 1;
1060
1061err:
1062	tcf_action_destroy(actions, bind);
1063	return err;
1064}
1065
1066void tcf_action_update_stats(struct tc_action *a, u64 bytes, u64 packets,
1067			     u64 drops, bool hw)
1068{
1069	if (a->cpu_bstats) {
1070		_bstats_cpu_update(this_cpu_ptr(a->cpu_bstats), bytes, packets);
1071
1072		this_cpu_ptr(a->cpu_qstats)->drops += drops;
1073
1074		if (hw)
1075			_bstats_cpu_update(this_cpu_ptr(a->cpu_bstats_hw),
1076					   bytes, packets);
1077		return;
1078	}
1079
1080	_bstats_update(&a->tcfa_bstats, bytes, packets);
1081	a->tcfa_qstats.drops += drops;
1082	if (hw)
1083		_bstats_update(&a->tcfa_bstats_hw, bytes, packets);
1084}
1085EXPORT_SYMBOL(tcf_action_update_stats);
1086
1087int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *p,
1088			  int compat_mode)
1089{
1090	int err = 0;
1091	struct gnet_dump d;
1092
1093	if (p == NULL)
1094		goto errout;
1095
1096	/* compat_mode being true specifies a call that is supposed
1097	 * to add additional backward compatibility statistic TLVs.
1098	 */
1099	if (compat_mode) {
1100		if (p->type == TCA_OLD_COMPAT)
1101			err = gnet_stats_start_copy_compat(skb, 0,
1102							   TCA_STATS,
1103							   TCA_XSTATS,
1104							   &p->tcfa_lock, &d,
1105							   TCA_PAD);
1106		else
1107			return 0;
1108	} else
1109		err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
1110					    &p->tcfa_lock, &d, TCA_ACT_PAD);
1111
1112	if (err < 0)
1113		goto errout;
1114
1115	if (gnet_stats_copy_basic(NULL, &d, p->cpu_bstats, &p->tcfa_bstats) < 0 ||
1116	    gnet_stats_copy_basic_hw(NULL, &d, p->cpu_bstats_hw,
1117				     &p->tcfa_bstats_hw) < 0 ||
1118	    gnet_stats_copy_rate_est(&d, &p->tcfa_rate_est) < 0 ||
1119	    gnet_stats_copy_queue(&d, p->cpu_qstats,
1120				  &p->tcfa_qstats,
1121				  p->tcfa_qstats.qlen) < 0)
1122		goto errout;
1123
1124	if (gnet_stats_finish_copy(&d) < 0)
1125		goto errout;
1126
1127	return 0;
1128
1129errout:
1130	return -1;
1131}
1132
1133static int tca_get_fill(struct sk_buff *skb, struct tc_action *actions[],
1134			u32 portid, u32 seq, u16 flags, int event, int bind,
1135			int ref)
1136{
1137	struct tcamsg *t;
1138	struct nlmsghdr *nlh;
1139	unsigned char *b = skb_tail_pointer(skb);
1140	struct nlattr *nest;
1141
1142	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*t), flags);
1143	if (!nlh)
1144		goto out_nlmsg_trim;
1145	t = nlmsg_data(nlh);
1146	t->tca_family = AF_UNSPEC;
1147	t->tca__pad1 = 0;
1148	t->tca__pad2 = 0;
1149
1150	nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
1151	if (!nest)
1152		goto out_nlmsg_trim;
1153
1154	if (tcf_action_dump(skb, actions, bind, ref, false) < 0)
1155		goto out_nlmsg_trim;
1156
1157	nla_nest_end(skb, nest);
1158
1159	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1160	return skb->len;
1161
1162out_nlmsg_trim:
1163	nlmsg_trim(skb, b);
1164	return -1;
1165}
1166
1167static int
1168tcf_get_notify(struct net *net, u32 portid, struct nlmsghdr *n,
1169	       struct tc_action *actions[], int event,
1170	       struct netlink_ext_ack *extack)
1171{
1172	struct sk_buff *skb;
1173
1174	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1175	if (!skb)
1176		return -ENOBUFS;
1177	if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, event,
1178			 0, 1) <= 0) {
1179		NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1180		kfree_skb(skb);
1181		return -EINVAL;
1182	}
1183
1184	return rtnl_unicast(skb, net, portid);
1185}
1186
1187static struct tc_action *tcf_action_get_1(struct net *net, struct nlattr *nla,
1188					  struct nlmsghdr *n, u32 portid,
1189					  struct netlink_ext_ack *extack)
1190{
1191	struct nlattr *tb[TCA_ACT_MAX + 1];
1192	const struct tc_action_ops *ops;
1193	struct tc_action *a;
1194	int index;
1195	int err;
1196
1197	err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1198					  tcf_action_policy, extack);
1199	if (err < 0)
1200		goto err_out;
1201
1202	err = -EINVAL;
1203	if (tb[TCA_ACT_INDEX] == NULL ||
1204	    nla_len(tb[TCA_ACT_INDEX]) < sizeof(index)) {
1205		NL_SET_ERR_MSG(extack, "Invalid TC action index value");
1206		goto err_out;
1207	}
1208	index = nla_get_u32(tb[TCA_ACT_INDEX]);
1209
1210	err = -EINVAL;
1211	ops = tc_lookup_action(tb[TCA_ACT_KIND]);
1212	if (!ops) { /* could happen in batch of actions */
1213		NL_SET_ERR_MSG(extack, "Specified TC action kind not found");
1214		goto err_out;
1215	}
1216	err = -ENOENT;
1217	if (ops->lookup(net, &a, index) == 0) {
1218		NL_SET_ERR_MSG(extack, "TC action with specified index not found");
1219		goto err_mod;
1220	}
1221
1222	module_put(ops->owner);
1223	return a;
1224
1225err_mod:
1226	module_put(ops->owner);
1227err_out:
1228	return ERR_PTR(err);
1229}
1230
1231static int tca_action_flush(struct net *net, struct nlattr *nla,
1232			    struct nlmsghdr *n, u32 portid,
1233			    struct netlink_ext_ack *extack)
1234{
1235	struct sk_buff *skb;
1236	unsigned char *b;
1237	struct nlmsghdr *nlh;
1238	struct tcamsg *t;
1239	struct netlink_callback dcb;
1240	struct nlattr *nest;
1241	struct nlattr *tb[TCA_ACT_MAX + 1];
1242	const struct tc_action_ops *ops;
1243	struct nlattr *kind;
1244	int err = -ENOMEM;
1245
1246	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1247	if (!skb)
1248		return err;
1249
1250	b = skb_tail_pointer(skb);
1251
1252	err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1253					  tcf_action_policy, extack);
1254	if (err < 0)
1255		goto err_out;
1256
1257	err = -EINVAL;
1258	kind = tb[TCA_ACT_KIND];
1259	ops = tc_lookup_action(kind);
1260	if (!ops) { /*some idjot trying to flush unknown action */
1261		NL_SET_ERR_MSG(extack, "Cannot flush unknown TC action");
1262		goto err_out;
1263	}
1264
1265	nlh = nlmsg_put(skb, portid, n->nlmsg_seq, RTM_DELACTION,
1266			sizeof(*t), 0);
1267	if (!nlh) {
1268		NL_SET_ERR_MSG(extack, "Failed to create TC action flush notification");
1269		goto out_module_put;
1270	}
1271	t = nlmsg_data(nlh);
1272	t->tca_family = AF_UNSPEC;
1273	t->tca__pad1 = 0;
1274	t->tca__pad2 = 0;
1275
1276	nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
1277	if (!nest) {
1278		NL_SET_ERR_MSG(extack, "Failed to add new netlink message");
1279		goto out_module_put;
1280	}
1281
1282	err = ops->walk(net, skb, &dcb, RTM_DELACTION, ops, extack);
1283	if (err <= 0) {
1284		nla_nest_cancel(skb, nest);
1285		goto out_module_put;
1286	}
1287
1288	nla_nest_end(skb, nest);
1289
1290	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1291	nlh->nlmsg_flags |= NLM_F_ROOT;
1292	module_put(ops->owner);
1293	err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1294			     n->nlmsg_flags & NLM_F_ECHO);
1295	if (err > 0)
1296		return 0;
1297	if (err < 0)
1298		NL_SET_ERR_MSG(extack, "Failed to send TC action flush notification");
1299
1300	return err;
1301
1302out_module_put:
1303	module_put(ops->owner);
1304err_out:
1305	kfree_skb(skb);
1306	return err;
1307}
1308
1309static int tcf_action_delete(struct net *net, struct tc_action *actions[])
1310{
1311	int i;
1312
1313	for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
1314		struct tc_action *a = actions[i];
1315		const struct tc_action_ops *ops = a->ops;
1316		/* Actions can be deleted concurrently so we must save their
1317		 * type and id to search again after reference is released.
1318		 */
1319		struct tcf_idrinfo *idrinfo = a->idrinfo;
1320		u32 act_index = a->tcfa_index;
1321
1322		actions[i] = NULL;
1323		if (tcf_action_put(a)) {
1324			/* last reference, action was deleted concurrently */
1325			module_put(ops->owner);
1326		} else  {
1327			int ret;
1328
1329			/* now do the delete */
1330			ret = tcf_idr_delete_index(idrinfo, act_index);
1331			if (ret < 0)
1332				return ret;
1333		}
1334	}
1335	return 0;
1336}
1337
1338static int
1339tcf_del_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[],
1340	       u32 portid, size_t attr_size, struct netlink_ext_ack *extack)
1341{
1342	int ret;
1343	struct sk_buff *skb;
1344
1345	skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1346			GFP_KERNEL);
1347	if (!skb)
1348		return -ENOBUFS;
1349
1350	if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, RTM_DELACTION,
1351			 0, 2) <= 0) {
1352		NL_SET_ERR_MSG(extack, "Failed to fill netlink TC action attributes");
1353		kfree_skb(skb);
1354		return -EINVAL;
1355	}
1356
1357	/* now do the delete */
1358	ret = tcf_action_delete(net, actions);
1359	if (ret < 0) {
1360		NL_SET_ERR_MSG(extack, "Failed to delete TC action");
1361		kfree_skb(skb);
1362		return ret;
1363	}
1364
1365	ret = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1366			     n->nlmsg_flags & NLM_F_ECHO);
1367	if (ret > 0)
1368		return 0;
1369	return ret;
1370}
1371
1372static int
1373tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
1374	      u32 portid, int event, struct netlink_ext_ack *extack)
1375{
1376	int i, ret;
1377	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1378	struct tc_action *act;
1379	size_t attr_size = 0;
1380	struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
1381
1382	ret = nla_parse_nested_deprecated(tb, TCA_ACT_MAX_PRIO, nla, NULL,
1383					  extack);
1384	if (ret < 0)
1385		return ret;
1386
1387	if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) {
1388		if (tb[1])
1389			return tca_action_flush(net, tb[1], n, portid, extack);
1390
1391		NL_SET_ERR_MSG(extack, "Invalid netlink attributes while flushing TC action");
1392		return -EINVAL;
1393	}
1394
1395	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1396		act = tcf_action_get_1(net, tb[i], n, portid, extack);
1397		if (IS_ERR(act)) {
1398			ret = PTR_ERR(act);
1399			goto err;
1400		}
1401		attr_size += tcf_action_fill_size(act);
1402		actions[i - 1] = act;
1403	}
1404
1405	attr_size = tcf_action_full_attrs_size(attr_size);
1406
1407	if (event == RTM_GETACTION)
1408		ret = tcf_get_notify(net, portid, n, actions, event, extack);
1409	else { /* delete */
1410		ret = tcf_del_notify(net, n, actions, portid, attr_size, extack);
1411		if (ret)
1412			goto err;
1413		return 0;
1414	}
1415err:
1416	tcf_action_put_many(actions);
1417	return ret;
1418}
1419
1420static int
1421tcf_add_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[],
1422	       u32 portid, size_t attr_size, struct netlink_ext_ack *extack)
1423{
1424	struct sk_buff *skb;
1425	int err = 0;
1426
1427	skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1428			GFP_KERNEL);
1429	if (!skb)
1430		return -ENOBUFS;
1431
1432	if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, n->nlmsg_flags,
1433			 RTM_NEWACTION, 0, 0) <= 0) {
1434		NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1435		kfree_skb(skb);
1436		return -EINVAL;
1437	}
1438
1439	err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1440			     n->nlmsg_flags & NLM_F_ECHO);
1441	if (err > 0)
1442		err = 0;
1443	return err;
1444}
1445
1446static int tcf_action_add(struct net *net, struct nlattr *nla,
1447			  struct nlmsghdr *n, u32 portid, int ovr,
1448			  struct netlink_ext_ack *extack)
1449{
1450	size_t attr_size = 0;
1451	int loop, ret;
1452	struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
1453
1454	for (loop = 0; loop < 10; loop++) {
1455		ret = tcf_action_init(net, NULL, nla, NULL, NULL, ovr, 0,
1456				      actions, &attr_size, true, extack);
1457		if (ret != -EAGAIN)
1458			break;
1459	}
1460
1461	if (ret < 0)
1462		return ret;
1463	ret = tcf_add_notify(net, n, actions, portid, attr_size, extack);
1464	if (ovr)
1465		tcf_action_put_many(actions);
1466
1467	return ret;
1468}
1469
 
1470static const struct nla_policy tcaa_policy[TCA_ROOT_MAX + 1] = {
1471	[TCA_ROOT_FLAGS] = NLA_POLICY_BITFIELD32(TCA_FLAG_LARGE_DUMP_ON),
 
1472	[TCA_ROOT_TIME_DELTA]      = { .type = NLA_U32 },
1473};
1474
1475static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n,
1476			 struct netlink_ext_ack *extack)
1477{
1478	struct net *net = sock_net(skb->sk);
1479	struct nlattr *tca[TCA_ROOT_MAX + 1];
1480	u32 portid = NETLINK_CB(skb).portid;
1481	int ret = 0, ovr = 0;
1482
1483	if ((n->nlmsg_type != RTM_GETACTION) &&
1484	    !netlink_capable(skb, CAP_NET_ADMIN))
1485		return -EPERM;
1486
1487	ret = nlmsg_parse_deprecated(n, sizeof(struct tcamsg), tca,
1488				     TCA_ROOT_MAX, NULL, extack);
1489	if (ret < 0)
1490		return ret;
1491
1492	if (tca[TCA_ACT_TAB] == NULL) {
1493		NL_SET_ERR_MSG(extack, "Netlink action attributes missing");
1494		return -EINVAL;
1495	}
1496
1497	/* n->nlmsg_flags & NLM_F_CREATE */
1498	switch (n->nlmsg_type) {
1499	case RTM_NEWACTION:
1500		/* we are going to assume all other flags
1501		 * imply create only if it doesn't exist
1502		 * Note that CREATE | EXCL implies that
1503		 * but since we want avoid ambiguity (eg when flags
1504		 * is zero) then just set this
1505		 */
1506		if (n->nlmsg_flags & NLM_F_REPLACE)
1507			ovr = 1;
1508		ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, portid, ovr,
1509				     extack);
1510		break;
1511	case RTM_DELACTION:
1512		ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
1513				    portid, RTM_DELACTION, extack);
1514		break;
1515	case RTM_GETACTION:
1516		ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
1517				    portid, RTM_GETACTION, extack);
1518		break;
1519	default:
1520		BUG();
1521	}
1522
1523	return ret;
1524}
1525
1526static struct nlattr *find_dump_kind(struct nlattr **nla)
1527{
1528	struct nlattr *tb1, *tb2[TCA_ACT_MAX + 1];
1529	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1530	struct nlattr *kind;
1531
1532	tb1 = nla[TCA_ACT_TAB];
1533	if (tb1 == NULL)
1534		return NULL;
1535
1536	if (nla_parse_deprecated(tb, TCA_ACT_MAX_PRIO, nla_data(tb1), NLMSG_ALIGN(nla_len(tb1)), NULL, NULL) < 0)
1537		return NULL;
1538
1539	if (tb[1] == NULL)
1540		return NULL;
1541	if (nla_parse_nested_deprecated(tb2, TCA_ACT_MAX, tb[1], tcf_action_policy, NULL) < 0)
1542		return NULL;
1543	kind = tb2[TCA_ACT_KIND];
1544
1545	return kind;
1546}
1547
1548static int tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
1549{
1550	struct net *net = sock_net(skb->sk);
1551	struct nlmsghdr *nlh;
1552	unsigned char *b = skb_tail_pointer(skb);
1553	struct nlattr *nest;
1554	struct tc_action_ops *a_o;
1555	int ret = 0;
1556	struct tcamsg *t = (struct tcamsg *) nlmsg_data(cb->nlh);
1557	struct nlattr *tb[TCA_ROOT_MAX + 1];
1558	struct nlattr *count_attr = NULL;
1559	unsigned long jiffy_since = 0;
1560	struct nlattr *kind = NULL;
1561	struct nla_bitfield32 bf;
1562	u32 msecs_since = 0;
1563	u32 act_count = 0;
1564
1565	ret = nlmsg_parse_deprecated(cb->nlh, sizeof(struct tcamsg), tb,
1566				     TCA_ROOT_MAX, tcaa_policy, cb->extack);
1567	if (ret < 0)
1568		return ret;
1569
1570	kind = find_dump_kind(tb);
1571	if (kind == NULL) {
1572		pr_info("tc_dump_action: action bad kind\n");
1573		return 0;
1574	}
1575
1576	a_o = tc_lookup_action(kind);
1577	if (a_o == NULL)
1578		return 0;
1579
1580	cb->args[2] = 0;
1581	if (tb[TCA_ROOT_FLAGS]) {
1582		bf = nla_get_bitfield32(tb[TCA_ROOT_FLAGS]);
1583		cb->args[2] = bf.value;
1584	}
1585
1586	if (tb[TCA_ROOT_TIME_DELTA]) {
1587		msecs_since = nla_get_u32(tb[TCA_ROOT_TIME_DELTA]);
1588	}
1589
1590	nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
1591			cb->nlh->nlmsg_type, sizeof(*t), 0);
1592	if (!nlh)
1593		goto out_module_put;
1594
1595	if (msecs_since)
1596		jiffy_since = jiffies - msecs_to_jiffies(msecs_since);
1597
1598	t = nlmsg_data(nlh);
1599	t->tca_family = AF_UNSPEC;
1600	t->tca__pad1 = 0;
1601	t->tca__pad2 = 0;
1602	cb->args[3] = jiffy_since;
1603	count_attr = nla_reserve(skb, TCA_ROOT_COUNT, sizeof(u32));
1604	if (!count_attr)
1605		goto out_module_put;
1606
1607	nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
1608	if (nest == NULL)
1609		goto out_module_put;
1610
1611	ret = a_o->walk(net, skb, cb, RTM_GETACTION, a_o, NULL);
1612	if (ret < 0)
1613		goto out_module_put;
1614
1615	if (ret > 0) {
1616		nla_nest_end(skb, nest);
1617		ret = skb->len;
1618		act_count = cb->args[1];
1619		memcpy(nla_data(count_attr), &act_count, sizeof(u32));
1620		cb->args[1] = 0;
1621	} else
1622		nlmsg_trim(skb, b);
1623
1624	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1625	if (NETLINK_CB(cb->skb).portid && ret)
1626		nlh->nlmsg_flags |= NLM_F_MULTI;
1627	module_put(a_o->owner);
1628	return skb->len;
1629
1630out_module_put:
1631	module_put(a_o->owner);
1632	nlmsg_trim(skb, b);
1633	return skb->len;
1634}
1635
1636static int __init tc_action_init(void)
1637{
1638	rtnl_register(PF_UNSPEC, RTM_NEWACTION, tc_ctl_action, NULL, 0);
1639	rtnl_register(PF_UNSPEC, RTM_DELACTION, tc_ctl_action, NULL, 0);
1640	rtnl_register(PF_UNSPEC, RTM_GETACTION, tc_ctl_action, tc_dump_action,
1641		      0);
1642
1643	return 0;
1644}
1645
1646subsys_initcall(tc_action_init);
v5.4
   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/act_api.h>
  23#include <net/netlink.h>
  24
  25static void tcf_action_goto_chain_exec(const struct tc_action *a,
  26				       struct tcf_result *res)
  27{
  28	const struct tcf_chain *chain = rcu_dereference_bh(a->goto_chain);
  29
  30	res->goto_tp = rcu_dereference_bh(chain->filter_chain);
  31}
  32
  33static void tcf_free_cookie_rcu(struct rcu_head *p)
  34{
  35	struct tc_cookie *cookie = container_of(p, struct tc_cookie, rcu);
  36
  37	kfree(cookie->data);
  38	kfree(cookie);
  39}
  40
  41static void tcf_set_action_cookie(struct tc_cookie __rcu **old_cookie,
  42				  struct tc_cookie *new_cookie)
  43{
  44	struct tc_cookie *old;
  45
  46	old = xchg((__force struct tc_cookie **)old_cookie, new_cookie);
  47	if (old)
  48		call_rcu(&old->rcu, tcf_free_cookie_rcu);
  49}
  50
  51int tcf_action_check_ctrlact(int action, struct tcf_proto *tp,
  52			     struct tcf_chain **newchain,
  53			     struct netlink_ext_ack *extack)
  54{
  55	int opcode = TC_ACT_EXT_OPCODE(action), ret = -EINVAL;
  56	u32 chain_index;
  57
  58	if (!opcode)
  59		ret = action > TC_ACT_VALUE_MAX ? -EINVAL : 0;
  60	else if (opcode <= TC_ACT_EXT_OPCODE_MAX || action == TC_ACT_UNSPEC)
  61		ret = 0;
  62	if (ret) {
  63		NL_SET_ERR_MSG(extack, "invalid control action");
  64		goto end;
  65	}
  66
  67	if (TC_ACT_EXT_CMP(action, TC_ACT_GOTO_CHAIN)) {
  68		chain_index = action & TC_ACT_EXT_VAL_MASK;
  69		if (!tp || !newchain) {
  70			ret = -EINVAL;
  71			NL_SET_ERR_MSG(extack,
  72				       "can't goto NULL proto/chain");
  73			goto end;
  74		}
  75		*newchain = tcf_chain_get_by_act(tp->chain->block, chain_index);
  76		if (!*newchain) {
  77			ret = -ENOMEM;
  78			NL_SET_ERR_MSG(extack,
  79				       "can't allocate goto_chain");
  80		}
  81	}
  82end:
  83	return ret;
  84}
  85EXPORT_SYMBOL(tcf_action_check_ctrlact);
  86
  87struct tcf_chain *tcf_action_set_ctrlact(struct tc_action *a, int action,
  88					 struct tcf_chain *goto_chain)
  89{
  90	a->tcfa_action = action;
  91	rcu_swap_protected(a->goto_chain, goto_chain, 1);
  92	return goto_chain;
  93}
  94EXPORT_SYMBOL(tcf_action_set_ctrlact);
  95
  96/* XXX: For standalone actions, we don't need a RCU grace period either, because
  97 * actions are always connected to filters and filters are already destroyed in
  98 * RCU callbacks, so after a RCU grace period actions are already disconnected
  99 * from filters. Readers later can not find us.
 100 */
 101static void free_tcf(struct tc_action *p)
 102{
 103	struct tcf_chain *chain = rcu_dereference_protected(p->goto_chain, 1);
 104
 105	free_percpu(p->cpu_bstats);
 106	free_percpu(p->cpu_bstats_hw);
 107	free_percpu(p->cpu_qstats);
 108
 109	tcf_set_action_cookie(&p->act_cookie, NULL);
 110	if (chain)
 111		tcf_chain_put_by_act(chain);
 112
 113	kfree(p);
 114}
 115
 116static void tcf_action_cleanup(struct tc_action *p)
 117{
 118	if (p->ops->cleanup)
 119		p->ops->cleanup(p);
 120
 121	gen_kill_estimator(&p->tcfa_rate_est);
 122	free_tcf(p);
 123}
 124
 125static int __tcf_action_put(struct tc_action *p, bool bind)
 126{
 127	struct tcf_idrinfo *idrinfo = p->idrinfo;
 128
 129	if (refcount_dec_and_mutex_lock(&p->tcfa_refcnt, &idrinfo->lock)) {
 130		if (bind)
 131			atomic_dec(&p->tcfa_bindcnt);
 132		idr_remove(&idrinfo->action_idr, p->tcfa_index);
 133		mutex_unlock(&idrinfo->lock);
 134
 135		tcf_action_cleanup(p);
 136		return 1;
 137	}
 138
 139	if (bind)
 140		atomic_dec(&p->tcfa_bindcnt);
 141
 142	return 0;
 143}
 144
 145int __tcf_idr_release(struct tc_action *p, bool bind, bool strict)
 146{
 147	int ret = 0;
 148
 149	/* Release with strict==1 and bind==0 is only called through act API
 150	 * interface (classifiers always bind). Only case when action with
 151	 * positive reference count and zero bind count can exist is when it was
 152	 * also created with act API (unbinding last classifier will destroy the
 153	 * action if it was created by classifier). So only case when bind count
 154	 * can be changed after initial check is when unbound action is
 155	 * destroyed by act API while classifier binds to action with same id
 156	 * concurrently. This result either creation of new action(same behavior
 157	 * as before), or reusing existing action if concurrent process
 158	 * increments reference count before action is deleted. Both scenarios
 159	 * are acceptable.
 160	 */
 161	if (p) {
 162		if (!bind && strict && atomic_read(&p->tcfa_bindcnt) > 0)
 163			return -EPERM;
 164
 165		if (__tcf_action_put(p, bind))
 166			ret = ACT_P_DELETED;
 167	}
 168
 169	return ret;
 170}
 171EXPORT_SYMBOL(__tcf_idr_release);
 172
 173static size_t tcf_action_shared_attrs_size(const struct tc_action *act)
 174{
 175	struct tc_cookie *act_cookie;
 176	u32 cookie_len = 0;
 177
 178	rcu_read_lock();
 179	act_cookie = rcu_dereference(act->act_cookie);
 180
 181	if (act_cookie)
 182		cookie_len = nla_total_size(act_cookie->len);
 183	rcu_read_unlock();
 184
 185	return  nla_total_size(0) /* action number nested */
 186		+ nla_total_size(IFNAMSIZ) /* TCA_ACT_KIND */
 187		+ cookie_len /* TCA_ACT_COOKIE */
 
 188		+ nla_total_size(0) /* TCA_ACT_STATS nested */
 
 189		/* TCA_STATS_BASIC */
 190		+ nla_total_size_64bit(sizeof(struct gnet_stats_basic))
 
 
 191		/* TCA_STATS_QUEUE */
 192		+ nla_total_size_64bit(sizeof(struct gnet_stats_queue))
 193		+ nla_total_size(0) /* TCA_OPTIONS nested */
 194		+ nla_total_size(sizeof(struct tcf_t)); /* TCA_GACT_TM */
 195}
 196
 197static size_t tcf_action_full_attrs_size(size_t sz)
 198{
 199	return NLMSG_HDRLEN                     /* struct nlmsghdr */
 200		+ sizeof(struct tcamsg)
 201		+ nla_total_size(0)             /* TCA_ACT_TAB nested */
 202		+ sz;
 203}
 204
 205static size_t tcf_action_fill_size(const struct tc_action *act)
 206{
 207	size_t sz = tcf_action_shared_attrs_size(act);
 208
 209	if (act->ops->get_fill_size)
 210		return act->ops->get_fill_size(act) + sz;
 211	return sz;
 212}
 213
 214static int tcf_dump_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb,
 215			   struct netlink_callback *cb)
 216{
 217	int err = 0, index = -1, s_i = 0, n_i = 0;
 218	u32 act_flags = cb->args[2];
 219	unsigned long jiffy_since = cb->args[3];
 220	struct nlattr *nest;
 221	struct idr *idr = &idrinfo->action_idr;
 222	struct tc_action *p;
 223	unsigned long id = 1;
 224	unsigned long tmp;
 225
 226	mutex_lock(&idrinfo->lock);
 227
 228	s_i = cb->args[0];
 229
 230	idr_for_each_entry_ul(idr, p, tmp, id) {
 231		index++;
 232		if (index < s_i)
 233			continue;
 
 
 234
 235		if (jiffy_since &&
 236		    time_after(jiffy_since,
 237			       (unsigned long)p->tcfa_tm.lastuse))
 238			continue;
 239
 240		nest = nla_nest_start_noflag(skb, n_i);
 241		if (!nest) {
 242			index--;
 243			goto nla_put_failure;
 244		}
 245		err = tcf_action_dump_1(skb, p, 0, 0);
 246		if (err < 0) {
 247			index--;
 248			nlmsg_trim(skb, nest);
 249			goto done;
 250		}
 251		nla_nest_end(skb, nest);
 252		n_i++;
 253		if (!(act_flags & TCA_FLAG_LARGE_DUMP_ON) &&
 254		    n_i >= TCA_ACT_MAX_PRIO)
 255			goto done;
 256	}
 257done:
 258	if (index >= 0)
 259		cb->args[0] = index + 1;
 260
 261	mutex_unlock(&idrinfo->lock);
 262	if (n_i) {
 263		if (act_flags & TCA_FLAG_LARGE_DUMP_ON)
 264			cb->args[1] = n_i;
 265	}
 266	return n_i;
 267
 268nla_put_failure:
 269	nla_nest_cancel(skb, nest);
 270	goto done;
 271}
 272
 273static int tcf_idr_release_unsafe(struct tc_action *p)
 274{
 275	if (atomic_read(&p->tcfa_bindcnt) > 0)
 276		return -EPERM;
 277
 278	if (refcount_dec_and_test(&p->tcfa_refcnt)) {
 279		idr_remove(&p->idrinfo->action_idr, p->tcfa_index);
 280		tcf_action_cleanup(p);
 281		return ACT_P_DELETED;
 282	}
 283
 284	return 0;
 285}
 286
 287static int tcf_del_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb,
 288			  const struct tc_action_ops *ops)
 289{
 290	struct nlattr *nest;
 291	int n_i = 0;
 292	int ret = -EINVAL;
 293	struct idr *idr = &idrinfo->action_idr;
 294	struct tc_action *p;
 295	unsigned long id = 1;
 296	unsigned long tmp;
 297
 298	nest = nla_nest_start_noflag(skb, 0);
 299	if (nest == NULL)
 300		goto nla_put_failure;
 301	if (nla_put_string(skb, TCA_KIND, ops->kind))
 302		goto nla_put_failure;
 303
 304	mutex_lock(&idrinfo->lock);
 305	idr_for_each_entry_ul(idr, p, tmp, id) {
 
 
 306		ret = tcf_idr_release_unsafe(p);
 307		if (ret == ACT_P_DELETED) {
 308			module_put(ops->owner);
 309			n_i++;
 310		} else if (ret < 0) {
 311			mutex_unlock(&idrinfo->lock);
 312			goto nla_put_failure;
 313		}
 314	}
 315	mutex_unlock(&idrinfo->lock);
 316
 317	if (nla_put_u32(skb, TCA_FCNT, n_i))
 318		goto nla_put_failure;
 319	nla_nest_end(skb, nest);
 320
 321	return n_i;
 322nla_put_failure:
 323	nla_nest_cancel(skb, nest);
 324	return ret;
 325}
 326
 327int tcf_generic_walker(struct tc_action_net *tn, struct sk_buff *skb,
 328		       struct netlink_callback *cb, int type,
 329		       const struct tc_action_ops *ops,
 330		       struct netlink_ext_ack *extack)
 331{
 332	struct tcf_idrinfo *idrinfo = tn->idrinfo;
 333
 334	if (type == RTM_DELACTION) {
 335		return tcf_del_walker(idrinfo, skb, ops);
 336	} else if (type == RTM_GETACTION) {
 337		return tcf_dump_walker(idrinfo, skb, cb);
 338	} else {
 339		WARN(1, "tcf_generic_walker: unknown command %d\n", type);
 340		NL_SET_ERR_MSG(extack, "tcf_generic_walker: unknown command");
 341		return -EINVAL;
 342	}
 343}
 344EXPORT_SYMBOL(tcf_generic_walker);
 345
 346int tcf_idr_search(struct tc_action_net *tn, struct tc_action **a, u32 index)
 347{
 348	struct tcf_idrinfo *idrinfo = tn->idrinfo;
 349	struct tc_action *p;
 350
 351	mutex_lock(&idrinfo->lock);
 352	p = idr_find(&idrinfo->action_idr, index);
 353	if (IS_ERR(p))
 354		p = NULL;
 355	else if (p)
 356		refcount_inc(&p->tcfa_refcnt);
 357	mutex_unlock(&idrinfo->lock);
 358
 359	if (p) {
 360		*a = p;
 361		return true;
 362	}
 363	return false;
 364}
 365EXPORT_SYMBOL(tcf_idr_search);
 366
 367static int tcf_idr_delete_index(struct tcf_idrinfo *idrinfo, u32 index)
 368{
 369	struct tc_action *p;
 370	int ret = 0;
 371
 372	mutex_lock(&idrinfo->lock);
 373	p = idr_find(&idrinfo->action_idr, index);
 374	if (!p) {
 375		mutex_unlock(&idrinfo->lock);
 376		return -ENOENT;
 377	}
 378
 379	if (!atomic_read(&p->tcfa_bindcnt)) {
 380		if (refcount_dec_and_test(&p->tcfa_refcnt)) {
 381			struct module *owner = p->ops->owner;
 382
 383			WARN_ON(p != idr_remove(&idrinfo->action_idr,
 384						p->tcfa_index));
 385			mutex_unlock(&idrinfo->lock);
 386
 387			tcf_action_cleanup(p);
 388			module_put(owner);
 389			return 0;
 390		}
 391		ret = 0;
 392	} else {
 393		ret = -EPERM;
 394	}
 395
 396	mutex_unlock(&idrinfo->lock);
 397	return ret;
 398}
 399
 400int tcf_idr_create(struct tc_action_net *tn, u32 index, struct nlattr *est,
 401		   struct tc_action **a, const struct tc_action_ops *ops,
 402		   int bind, bool cpustats)
 403{
 404	struct tc_action *p = kzalloc(ops->size, GFP_KERNEL);
 405	struct tcf_idrinfo *idrinfo = tn->idrinfo;
 406	int err = -ENOMEM;
 407
 408	if (unlikely(!p))
 409		return -ENOMEM;
 410	refcount_set(&p->tcfa_refcnt, 1);
 411	if (bind)
 412		atomic_set(&p->tcfa_bindcnt, 1);
 413
 414	if (cpustats) {
 415		p->cpu_bstats = netdev_alloc_pcpu_stats(struct gnet_stats_basic_cpu);
 416		if (!p->cpu_bstats)
 417			goto err1;
 418		p->cpu_bstats_hw = netdev_alloc_pcpu_stats(struct gnet_stats_basic_cpu);
 419		if (!p->cpu_bstats_hw)
 420			goto err2;
 421		p->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
 422		if (!p->cpu_qstats)
 423			goto err3;
 424	}
 425	spin_lock_init(&p->tcfa_lock);
 426	p->tcfa_index = index;
 427	p->tcfa_tm.install = jiffies;
 428	p->tcfa_tm.lastuse = jiffies;
 429	p->tcfa_tm.firstuse = 0;
 
 430	if (est) {
 431		err = gen_new_estimator(&p->tcfa_bstats, p->cpu_bstats,
 432					&p->tcfa_rate_est,
 433					&p->tcfa_lock, NULL, est);
 434		if (err)
 435			goto err4;
 436	}
 437
 438	p->idrinfo = idrinfo;
 439	p->ops = ops;
 440	*a = p;
 441	return 0;
 442err4:
 443	free_percpu(p->cpu_qstats);
 444err3:
 445	free_percpu(p->cpu_bstats_hw);
 446err2:
 447	free_percpu(p->cpu_bstats);
 448err1:
 449	kfree(p);
 450	return err;
 451}
 452EXPORT_SYMBOL(tcf_idr_create);
 453
 454void tcf_idr_insert(struct tc_action_net *tn, struct tc_action *a)
 455{
 456	struct tcf_idrinfo *idrinfo = tn->idrinfo;
 457
 458	mutex_lock(&idrinfo->lock);
 459	/* Replace ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */
 460	WARN_ON(!IS_ERR(idr_replace(&idrinfo->action_idr, a, a->tcfa_index)));
 461	mutex_unlock(&idrinfo->lock);
 462}
 463EXPORT_SYMBOL(tcf_idr_insert);
 464
 465/* Cleanup idr index that was allocated but not initialized. */
 466
 467void tcf_idr_cleanup(struct tc_action_net *tn, u32 index)
 468{
 469	struct tcf_idrinfo *idrinfo = tn->idrinfo;
 470
 471	mutex_lock(&idrinfo->lock);
 472	/* Remove ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */
 473	WARN_ON(!IS_ERR(idr_remove(&idrinfo->action_idr, index)));
 474	mutex_unlock(&idrinfo->lock);
 475}
 476EXPORT_SYMBOL(tcf_idr_cleanup);
 477
 478/* Check if action with specified index exists. If actions is found, increments
 479 * its reference and bind counters, and return 1. Otherwise insert temporary
 480 * error pointer (to prevent concurrent users from inserting actions with same
 481 * index) and return 0.
 482 */
 483
 484int tcf_idr_check_alloc(struct tc_action_net *tn, u32 *index,
 485			struct tc_action **a, int bind)
 486{
 487	struct tcf_idrinfo *idrinfo = tn->idrinfo;
 488	struct tc_action *p;
 489	int ret;
 490
 491again:
 492	mutex_lock(&idrinfo->lock);
 493	if (*index) {
 494		p = idr_find(&idrinfo->action_idr, *index);
 495		if (IS_ERR(p)) {
 496			/* This means that another process allocated
 497			 * index but did not assign the pointer yet.
 498			 */
 499			mutex_unlock(&idrinfo->lock);
 500			goto again;
 501		}
 502
 503		if (p) {
 504			refcount_inc(&p->tcfa_refcnt);
 505			if (bind)
 506				atomic_inc(&p->tcfa_bindcnt);
 507			*a = p;
 508			ret = 1;
 509		} else {
 510			*a = NULL;
 511			ret = idr_alloc_u32(&idrinfo->action_idr, NULL, index,
 512					    *index, GFP_KERNEL);
 513			if (!ret)
 514				idr_replace(&idrinfo->action_idr,
 515					    ERR_PTR(-EBUSY), *index);
 516		}
 517	} else {
 518		*index = 1;
 519		*a = NULL;
 520		ret = idr_alloc_u32(&idrinfo->action_idr, NULL, index,
 521				    UINT_MAX, GFP_KERNEL);
 522		if (!ret)
 523			idr_replace(&idrinfo->action_idr, ERR_PTR(-EBUSY),
 524				    *index);
 525	}
 526	mutex_unlock(&idrinfo->lock);
 527	return ret;
 528}
 529EXPORT_SYMBOL(tcf_idr_check_alloc);
 530
 531void tcf_idrinfo_destroy(const struct tc_action_ops *ops,
 532			 struct tcf_idrinfo *idrinfo)
 533{
 534	struct idr *idr = &idrinfo->action_idr;
 535	struct tc_action *p;
 536	int ret;
 537	unsigned long id = 1;
 538	unsigned long tmp;
 539
 540	idr_for_each_entry_ul(idr, p, tmp, id) {
 541		ret = __tcf_idr_release(p, false, true);
 542		if (ret == ACT_P_DELETED)
 543			module_put(ops->owner);
 544		else if (ret < 0)
 545			return;
 546	}
 547	idr_destroy(&idrinfo->action_idr);
 548}
 549EXPORT_SYMBOL(tcf_idrinfo_destroy);
 550
 551static LIST_HEAD(act_base);
 552static DEFINE_RWLOCK(act_mod_lock);
 553
 554int tcf_register_action(struct tc_action_ops *act,
 555			struct pernet_operations *ops)
 556{
 557	struct tc_action_ops *a;
 558	int ret;
 559
 560	if (!act->act || !act->dump || !act->init || !act->walk || !act->lookup)
 561		return -EINVAL;
 562
 563	/* We have to register pernet ops before making the action ops visible,
 564	 * otherwise tcf_action_init_1() could get a partially initialized
 565	 * netns.
 566	 */
 567	ret = register_pernet_subsys(ops);
 568	if (ret)
 569		return ret;
 570
 571	write_lock(&act_mod_lock);
 572	list_for_each_entry(a, &act_base, head) {
 573		if (act->id == a->id || (strcmp(act->kind, a->kind) == 0)) {
 574			write_unlock(&act_mod_lock);
 575			unregister_pernet_subsys(ops);
 576			return -EEXIST;
 577		}
 578	}
 579	list_add_tail(&act->head, &act_base);
 580	write_unlock(&act_mod_lock);
 581
 582	return 0;
 583}
 584EXPORT_SYMBOL(tcf_register_action);
 585
 586int tcf_unregister_action(struct tc_action_ops *act,
 587			  struct pernet_operations *ops)
 588{
 589	struct tc_action_ops *a;
 590	int err = -ENOENT;
 591
 592	write_lock(&act_mod_lock);
 593	list_for_each_entry(a, &act_base, head) {
 594		if (a == act) {
 595			list_del(&act->head);
 596			err = 0;
 597			break;
 598		}
 599	}
 600	write_unlock(&act_mod_lock);
 601	if (!err)
 602		unregister_pernet_subsys(ops);
 603	return err;
 604}
 605EXPORT_SYMBOL(tcf_unregister_action);
 606
 607/* lookup by name */
 608static struct tc_action_ops *tc_lookup_action_n(char *kind)
 609{
 610	struct tc_action_ops *a, *res = NULL;
 611
 612	if (kind) {
 613		read_lock(&act_mod_lock);
 614		list_for_each_entry(a, &act_base, head) {
 615			if (strcmp(kind, a->kind) == 0) {
 616				if (try_module_get(a->owner))
 617					res = a;
 618				break;
 619			}
 620		}
 621		read_unlock(&act_mod_lock);
 622	}
 623	return res;
 624}
 625
 626/* lookup by nlattr */
 627static struct tc_action_ops *tc_lookup_action(struct nlattr *kind)
 628{
 629	struct tc_action_ops *a, *res = NULL;
 630
 631	if (kind) {
 632		read_lock(&act_mod_lock);
 633		list_for_each_entry(a, &act_base, head) {
 634			if (nla_strcmp(kind, a->kind) == 0) {
 635				if (try_module_get(a->owner))
 636					res = a;
 637				break;
 638			}
 639		}
 640		read_unlock(&act_mod_lock);
 641	}
 642	return res;
 643}
 644
 645/*TCA_ACT_MAX_PRIO is 32, there count upto 32 */
 646#define TCA_ACT_MAX_PRIO_MASK 0x1FF
 647int tcf_action_exec(struct sk_buff *skb, struct tc_action **actions,
 648		    int nr_actions, struct tcf_result *res)
 649{
 650	u32 jmp_prgcnt = 0;
 651	u32 jmp_ttl = TCA_ACT_MAX_PRIO; /*matches actions per filter */
 652	int i;
 653	int ret = TC_ACT_OK;
 654
 655	if (skb_skip_tc_classify(skb))
 656		return TC_ACT_OK;
 657
 658restart_act_graph:
 659	for (i = 0; i < nr_actions; i++) {
 660		const struct tc_action *a = actions[i];
 661
 662		if (jmp_prgcnt > 0) {
 663			jmp_prgcnt -= 1;
 664			continue;
 665		}
 666repeat:
 667		ret = a->ops->act(skb, a, res);
 668		if (ret == TC_ACT_REPEAT)
 669			goto repeat;	/* we need a ttl - JHS */
 670
 671		if (TC_ACT_EXT_CMP(ret, TC_ACT_JUMP)) {
 672			jmp_prgcnt = ret & TCA_ACT_MAX_PRIO_MASK;
 673			if (!jmp_prgcnt || (jmp_prgcnt > nr_actions)) {
 674				/* faulty opcode, stop pipeline */
 675				return TC_ACT_OK;
 676			} else {
 677				jmp_ttl -= 1;
 678				if (jmp_ttl > 0)
 679					goto restart_act_graph;
 680				else /* faulty graph, stop pipeline */
 681					return TC_ACT_OK;
 682			}
 683		} else if (TC_ACT_EXT_CMP(ret, TC_ACT_GOTO_CHAIN)) {
 684			if (unlikely(!rcu_access_pointer(a->goto_chain))) {
 685				net_warn_ratelimited("can't go to NULL chain!\n");
 686				return TC_ACT_SHOT;
 687			}
 688			tcf_action_goto_chain_exec(a, res);
 689		}
 690
 691		if (ret != TC_ACT_PIPE)
 692			break;
 693	}
 694
 695	return ret;
 696}
 697EXPORT_SYMBOL(tcf_action_exec);
 698
 699int tcf_action_destroy(struct tc_action *actions[], int bind)
 700{
 701	const struct tc_action_ops *ops;
 702	struct tc_action *a;
 703	int ret = 0, i;
 704
 705	for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
 706		a = actions[i];
 707		actions[i] = NULL;
 708		ops = a->ops;
 709		ret = __tcf_idr_release(a, bind, true);
 710		if (ret == ACT_P_DELETED)
 711			module_put(ops->owner);
 712		else if (ret < 0)
 713			return ret;
 714	}
 715	return ret;
 716}
 717
 718static int tcf_action_destroy_1(struct tc_action *a, int bind)
 719{
 720	struct tc_action *actions[] = { a, NULL };
 721
 722	return tcf_action_destroy(actions, bind);
 723}
 724
 725static int tcf_action_put(struct tc_action *p)
 726{
 727	return __tcf_action_put(p, false);
 728}
 729
 730/* Put all actions in this array, skip those NULL's. */
 731static void tcf_action_put_many(struct tc_action *actions[])
 732{
 733	int i;
 734
 735	for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
 736		struct tc_action *a = actions[i];
 737		const struct tc_action_ops *ops;
 738
 739		if (!a)
 740			continue;
 741		ops = a->ops;
 742		if (tcf_action_put(a))
 743			module_put(ops->owner);
 744	}
 745}
 746
 747int
 748tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 749{
 750	return a->ops->dump(skb, a, bind, ref);
 751}
 752
 753int
 754tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 755{
 756	int err = -EINVAL;
 757	unsigned char *b = skb_tail_pointer(skb);
 758	struct nlattr *nest;
 759	struct tc_cookie *cookie;
 760
 761	if (nla_put_string(skb, TCA_KIND, a->ops->kind))
 762		goto nla_put_failure;
 763	if (tcf_action_copy_stats(skb, a, 0))
 764		goto nla_put_failure;
 765
 766	rcu_read_lock();
 767	cookie = rcu_dereference(a->act_cookie);
 768	if (cookie) {
 769		if (nla_put(skb, TCA_ACT_COOKIE, cookie->len, cookie->data)) {
 770			rcu_read_unlock();
 771			goto nla_put_failure;
 772		}
 773	}
 774	rcu_read_unlock();
 775
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 776	nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
 777	if (nest == NULL)
 778		goto nla_put_failure;
 779	err = tcf_action_dump_old(skb, a, bind, ref);
 780	if (err > 0) {
 781		nla_nest_end(skb, nest);
 782		return err;
 783	}
 784
 785nla_put_failure:
 786	nlmsg_trim(skb, b);
 787	return -1;
 788}
 789EXPORT_SYMBOL(tcf_action_dump_1);
 790
 791int tcf_action_dump(struct sk_buff *skb, struct tc_action *actions[],
 792		    int bind, int ref)
 793{
 794	struct tc_action *a;
 795	int err = -EINVAL, i;
 796	struct nlattr *nest;
 797
 798	for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
 799		a = actions[i];
 800		nest = nla_nest_start_noflag(skb, i + 1);
 801		if (nest == NULL)
 802			goto nla_put_failure;
 803		err = tcf_action_dump_1(skb, a, bind, ref);
 
 804		if (err < 0)
 805			goto errout;
 806		nla_nest_end(skb, nest);
 807	}
 808
 809	return 0;
 810
 811nla_put_failure:
 812	err = -EINVAL;
 813errout:
 814	nla_nest_cancel(skb, nest);
 815	return err;
 816}
 817
 818static struct tc_cookie *nla_memdup_cookie(struct nlattr **tb)
 819{
 820	struct tc_cookie *c = kzalloc(sizeof(*c), GFP_KERNEL);
 821	if (!c)
 822		return NULL;
 823
 824	c->data = nla_memdup(tb[TCA_ACT_COOKIE], GFP_KERNEL);
 825	if (!c->data) {
 826		kfree(c);
 827		return NULL;
 828	}
 829	c->len = nla_len(tb[TCA_ACT_COOKIE]);
 830
 831	return c;
 832}
 833
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 834static const struct nla_policy tcf_action_policy[TCA_ACT_MAX + 1] = {
 835	[TCA_ACT_KIND]		= { .type = NLA_STRING },
 836	[TCA_ACT_INDEX]		= { .type = NLA_U32 },
 837	[TCA_ACT_COOKIE]	= { .type = NLA_BINARY,
 838				    .len = TC_COOKIE_MAX_SIZE },
 839	[TCA_ACT_OPTIONS]	= { .type = NLA_NESTED },
 
 
 840};
 841
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 842struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
 843				    struct nlattr *nla, struct nlattr *est,
 844				    char *name, int ovr, int bind,
 845				    bool rtnl_held,
 846				    struct netlink_ext_ack *extack)
 847{
 
 
 848	struct tc_action *a;
 849	struct tc_action_ops *a_o;
 850	struct tc_cookie *cookie = NULL;
 851	char act_name[IFNAMSIZ];
 852	struct nlattr *tb[TCA_ACT_MAX + 1];
 853	struct nlattr *kind;
 854	int err;
 855
 856	if (name == NULL) {
 857		err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
 858						  tcf_action_policy, extack);
 859		if (err < 0)
 860			goto err_out;
 861		err = -EINVAL;
 862		kind = tb[TCA_ACT_KIND];
 863		if (!kind) {
 864			NL_SET_ERR_MSG(extack, "TC action kind must be specified");
 865			goto err_out;
 866		}
 867		if (nla_strlcpy(act_name, kind, IFNAMSIZ) >= IFNAMSIZ) {
 868			NL_SET_ERR_MSG(extack, "TC action name too long");
 869			goto err_out;
 870		}
 871		if (tb[TCA_ACT_COOKIE]) {
 872			cookie = nla_memdup_cookie(tb);
 873			if (!cookie) {
 874				NL_SET_ERR_MSG(extack, "No memory to generate TC cookie");
 875				err = -ENOMEM;
 876				goto err_out;
 877			}
 878		}
 
 
 
 879	} else {
 880		if (strlcpy(act_name, name, IFNAMSIZ) >= IFNAMSIZ) {
 881			NL_SET_ERR_MSG(extack, "TC action name too long");
 882			err = -EINVAL;
 883			goto err_out;
 884		}
 885	}
 886
 887	a_o = tc_lookup_action_n(act_name);
 888	if (a_o == NULL) {
 889#ifdef CONFIG_MODULES
 890		if (rtnl_held)
 891			rtnl_unlock();
 892		request_module("act_%s", act_name);
 893		if (rtnl_held)
 894			rtnl_lock();
 895
 896		a_o = tc_lookup_action_n(act_name);
 897
 898		/* We dropped the RTNL semaphore in order to
 899		 * perform the module load.  So, even if we
 900		 * succeeded in loading the module we have to
 901		 * tell the caller to replay the request.  We
 902		 * indicate this using -EAGAIN.
 903		 */
 904		if (a_o != NULL) {
 905			err = -EAGAIN;
 906			goto err_mod;
 907		}
 908#endif
 909		NL_SET_ERR_MSG(extack, "Failed to load TC action module");
 910		err = -ENOENT;
 911		goto err_out;
 912	}
 913
 914	/* backward compatibility for policer */
 915	if (name == NULL)
 916		err = a_o->init(net, tb[TCA_ACT_OPTIONS], est, &a, ovr, bind,
 917				rtnl_held, tp, extack);
 918	else
 919		err = a_o->init(net, nla, est, &a, ovr, bind, rtnl_held,
 920				tp, extack);
 921	if (err < 0)
 922		goto err_mod;
 923
 924	if (!name && tb[TCA_ACT_COOKIE])
 925		tcf_set_action_cookie(&a->act_cookie, cookie);
 926
 
 
 
 927	/* module count goes up only when brand new policy is created
 928	 * if it exists and is only bound to in a_o->init() then
 929	 * ACT_P_CREATED is not returned (a zero is).
 930	 */
 931	if (err != ACT_P_CREATED)
 932		module_put(a_o->owner);
 933
 934	if (TC_ACT_EXT_CMP(a->tcfa_action, TC_ACT_GOTO_CHAIN) &&
 935	    !rcu_access_pointer(a->goto_chain)) {
 936		tcf_action_destroy_1(a, bind);
 937		NL_SET_ERR_MSG(extack, "can't use goto chain with NULL chain");
 938		return ERR_PTR(-EINVAL);
 939	}
 940
 941	return a;
 942
 943err_mod:
 944	module_put(a_o->owner);
 945err_out:
 946	if (cookie) {
 947		kfree(cookie->data);
 948		kfree(cookie);
 949	}
 950	return ERR_PTR(err);
 951}
 952
 953/* Returns numbers of initialized actions or negative error. */
 954
 955int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla,
 956		    struct nlattr *est, char *name, int ovr, int bind,
 957		    struct tc_action *actions[], size_t *attr_size,
 958		    bool rtnl_held, struct netlink_ext_ack *extack)
 959{
 960	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
 961	struct tc_action *act;
 962	size_t sz = 0;
 963	int err;
 964	int i;
 965
 966	err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX_PRIO, nla, NULL,
 967					  extack);
 968	if (err < 0)
 969		return err;
 970
 971	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
 972		act = tcf_action_init_1(net, tp, tb[i], est, name, ovr, bind,
 973					rtnl_held, extack);
 974		if (IS_ERR(act)) {
 975			err = PTR_ERR(act);
 976			goto err;
 977		}
 978		act->order = i;
 979		sz += tcf_action_fill_size(act);
 980		/* Start from index 0 */
 981		actions[i - 1] = act;
 982	}
 983
 
 
 
 
 
 984	*attr_size = tcf_action_full_attrs_size(sz);
 985	return i - 1;
 986
 987err:
 988	tcf_action_destroy(actions, bind);
 989	return err;
 990}
 991
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 992int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *p,
 993			  int compat_mode)
 994{
 995	int err = 0;
 996	struct gnet_dump d;
 997
 998	if (p == NULL)
 999		goto errout;
1000
1001	/* compat_mode being true specifies a call that is supposed
1002	 * to add additional backward compatibility statistic TLVs.
1003	 */
1004	if (compat_mode) {
1005		if (p->type == TCA_OLD_COMPAT)
1006			err = gnet_stats_start_copy_compat(skb, 0,
1007							   TCA_STATS,
1008							   TCA_XSTATS,
1009							   &p->tcfa_lock, &d,
1010							   TCA_PAD);
1011		else
1012			return 0;
1013	} else
1014		err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
1015					    &p->tcfa_lock, &d, TCA_ACT_PAD);
1016
1017	if (err < 0)
1018		goto errout;
1019
1020	if (gnet_stats_copy_basic(NULL, &d, p->cpu_bstats, &p->tcfa_bstats) < 0 ||
1021	    gnet_stats_copy_basic_hw(NULL, &d, p->cpu_bstats_hw,
1022				     &p->tcfa_bstats_hw) < 0 ||
1023	    gnet_stats_copy_rate_est(&d, &p->tcfa_rate_est) < 0 ||
1024	    gnet_stats_copy_queue(&d, p->cpu_qstats,
1025				  &p->tcfa_qstats,
1026				  p->tcfa_qstats.qlen) < 0)
1027		goto errout;
1028
1029	if (gnet_stats_finish_copy(&d) < 0)
1030		goto errout;
1031
1032	return 0;
1033
1034errout:
1035	return -1;
1036}
1037
1038static int tca_get_fill(struct sk_buff *skb, struct tc_action *actions[],
1039			u32 portid, u32 seq, u16 flags, int event, int bind,
1040			int ref)
1041{
1042	struct tcamsg *t;
1043	struct nlmsghdr *nlh;
1044	unsigned char *b = skb_tail_pointer(skb);
1045	struct nlattr *nest;
1046
1047	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*t), flags);
1048	if (!nlh)
1049		goto out_nlmsg_trim;
1050	t = nlmsg_data(nlh);
1051	t->tca_family = AF_UNSPEC;
1052	t->tca__pad1 = 0;
1053	t->tca__pad2 = 0;
1054
1055	nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
1056	if (!nest)
1057		goto out_nlmsg_trim;
1058
1059	if (tcf_action_dump(skb, actions, bind, ref) < 0)
1060		goto out_nlmsg_trim;
1061
1062	nla_nest_end(skb, nest);
1063
1064	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1065	return skb->len;
1066
1067out_nlmsg_trim:
1068	nlmsg_trim(skb, b);
1069	return -1;
1070}
1071
1072static int
1073tcf_get_notify(struct net *net, u32 portid, struct nlmsghdr *n,
1074	       struct tc_action *actions[], int event,
1075	       struct netlink_ext_ack *extack)
1076{
1077	struct sk_buff *skb;
1078
1079	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1080	if (!skb)
1081		return -ENOBUFS;
1082	if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, event,
1083			 0, 1) <= 0) {
1084		NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1085		kfree_skb(skb);
1086		return -EINVAL;
1087	}
1088
1089	return rtnl_unicast(skb, net, portid);
1090}
1091
1092static struct tc_action *tcf_action_get_1(struct net *net, struct nlattr *nla,
1093					  struct nlmsghdr *n, u32 portid,
1094					  struct netlink_ext_ack *extack)
1095{
1096	struct nlattr *tb[TCA_ACT_MAX + 1];
1097	const struct tc_action_ops *ops;
1098	struct tc_action *a;
1099	int index;
1100	int err;
1101
1102	err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1103					  tcf_action_policy, extack);
1104	if (err < 0)
1105		goto err_out;
1106
1107	err = -EINVAL;
1108	if (tb[TCA_ACT_INDEX] == NULL ||
1109	    nla_len(tb[TCA_ACT_INDEX]) < sizeof(index)) {
1110		NL_SET_ERR_MSG(extack, "Invalid TC action index value");
1111		goto err_out;
1112	}
1113	index = nla_get_u32(tb[TCA_ACT_INDEX]);
1114
1115	err = -EINVAL;
1116	ops = tc_lookup_action(tb[TCA_ACT_KIND]);
1117	if (!ops) { /* could happen in batch of actions */
1118		NL_SET_ERR_MSG(extack, "Specified TC action kind not found");
1119		goto err_out;
1120	}
1121	err = -ENOENT;
1122	if (ops->lookup(net, &a, index) == 0) {
1123		NL_SET_ERR_MSG(extack, "TC action with specified index not found");
1124		goto err_mod;
1125	}
1126
1127	module_put(ops->owner);
1128	return a;
1129
1130err_mod:
1131	module_put(ops->owner);
1132err_out:
1133	return ERR_PTR(err);
1134}
1135
1136static int tca_action_flush(struct net *net, struct nlattr *nla,
1137			    struct nlmsghdr *n, u32 portid,
1138			    struct netlink_ext_ack *extack)
1139{
1140	struct sk_buff *skb;
1141	unsigned char *b;
1142	struct nlmsghdr *nlh;
1143	struct tcamsg *t;
1144	struct netlink_callback dcb;
1145	struct nlattr *nest;
1146	struct nlattr *tb[TCA_ACT_MAX + 1];
1147	const struct tc_action_ops *ops;
1148	struct nlattr *kind;
1149	int err = -ENOMEM;
1150
1151	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1152	if (!skb)
1153		return err;
1154
1155	b = skb_tail_pointer(skb);
1156
1157	err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1158					  tcf_action_policy, extack);
1159	if (err < 0)
1160		goto err_out;
1161
1162	err = -EINVAL;
1163	kind = tb[TCA_ACT_KIND];
1164	ops = tc_lookup_action(kind);
1165	if (!ops) { /*some idjot trying to flush unknown action */
1166		NL_SET_ERR_MSG(extack, "Cannot flush unknown TC action");
1167		goto err_out;
1168	}
1169
1170	nlh = nlmsg_put(skb, portid, n->nlmsg_seq, RTM_DELACTION,
1171			sizeof(*t), 0);
1172	if (!nlh) {
1173		NL_SET_ERR_MSG(extack, "Failed to create TC action flush notification");
1174		goto out_module_put;
1175	}
1176	t = nlmsg_data(nlh);
1177	t->tca_family = AF_UNSPEC;
1178	t->tca__pad1 = 0;
1179	t->tca__pad2 = 0;
1180
1181	nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
1182	if (!nest) {
1183		NL_SET_ERR_MSG(extack, "Failed to add new netlink message");
1184		goto out_module_put;
1185	}
1186
1187	err = ops->walk(net, skb, &dcb, RTM_DELACTION, ops, extack);
1188	if (err <= 0) {
1189		nla_nest_cancel(skb, nest);
1190		goto out_module_put;
1191	}
1192
1193	nla_nest_end(skb, nest);
1194
1195	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1196	nlh->nlmsg_flags |= NLM_F_ROOT;
1197	module_put(ops->owner);
1198	err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1199			     n->nlmsg_flags & NLM_F_ECHO);
1200	if (err > 0)
1201		return 0;
1202	if (err < 0)
1203		NL_SET_ERR_MSG(extack, "Failed to send TC action flush notification");
1204
1205	return err;
1206
1207out_module_put:
1208	module_put(ops->owner);
1209err_out:
1210	kfree_skb(skb);
1211	return err;
1212}
1213
1214static int tcf_action_delete(struct net *net, struct tc_action *actions[])
1215{
1216	int i;
1217
1218	for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
1219		struct tc_action *a = actions[i];
1220		const struct tc_action_ops *ops = a->ops;
1221		/* Actions can be deleted concurrently so we must save their
1222		 * type and id to search again after reference is released.
1223		 */
1224		struct tcf_idrinfo *idrinfo = a->idrinfo;
1225		u32 act_index = a->tcfa_index;
1226
1227		actions[i] = NULL;
1228		if (tcf_action_put(a)) {
1229			/* last reference, action was deleted concurrently */
1230			module_put(ops->owner);
1231		} else  {
1232			int ret;
1233
1234			/* now do the delete */
1235			ret = tcf_idr_delete_index(idrinfo, act_index);
1236			if (ret < 0)
1237				return ret;
1238		}
1239	}
1240	return 0;
1241}
1242
1243static int
1244tcf_del_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[],
1245	       u32 portid, size_t attr_size, struct netlink_ext_ack *extack)
1246{
1247	int ret;
1248	struct sk_buff *skb;
1249
1250	skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1251			GFP_KERNEL);
1252	if (!skb)
1253		return -ENOBUFS;
1254
1255	if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, RTM_DELACTION,
1256			 0, 2) <= 0) {
1257		NL_SET_ERR_MSG(extack, "Failed to fill netlink TC action attributes");
1258		kfree_skb(skb);
1259		return -EINVAL;
1260	}
1261
1262	/* now do the delete */
1263	ret = tcf_action_delete(net, actions);
1264	if (ret < 0) {
1265		NL_SET_ERR_MSG(extack, "Failed to delete TC action");
1266		kfree_skb(skb);
1267		return ret;
1268	}
1269
1270	ret = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1271			     n->nlmsg_flags & NLM_F_ECHO);
1272	if (ret > 0)
1273		return 0;
1274	return ret;
1275}
1276
1277static int
1278tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
1279	      u32 portid, int event, struct netlink_ext_ack *extack)
1280{
1281	int i, ret;
1282	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1283	struct tc_action *act;
1284	size_t attr_size = 0;
1285	struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
1286
1287	ret = nla_parse_nested_deprecated(tb, TCA_ACT_MAX_PRIO, nla, NULL,
1288					  extack);
1289	if (ret < 0)
1290		return ret;
1291
1292	if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) {
1293		if (tb[1])
1294			return tca_action_flush(net, tb[1], n, portid, extack);
1295
1296		NL_SET_ERR_MSG(extack, "Invalid netlink attributes while flushing TC action");
1297		return -EINVAL;
1298	}
1299
1300	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1301		act = tcf_action_get_1(net, tb[i], n, portid, extack);
1302		if (IS_ERR(act)) {
1303			ret = PTR_ERR(act);
1304			goto err;
1305		}
1306		attr_size += tcf_action_fill_size(act);
1307		actions[i - 1] = act;
1308	}
1309
1310	attr_size = tcf_action_full_attrs_size(attr_size);
1311
1312	if (event == RTM_GETACTION)
1313		ret = tcf_get_notify(net, portid, n, actions, event, extack);
1314	else { /* delete */
1315		ret = tcf_del_notify(net, n, actions, portid, attr_size, extack);
1316		if (ret)
1317			goto err;
1318		return 0;
1319	}
1320err:
1321	tcf_action_put_many(actions);
1322	return ret;
1323}
1324
1325static int
1326tcf_add_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[],
1327	       u32 portid, size_t attr_size, struct netlink_ext_ack *extack)
1328{
1329	struct sk_buff *skb;
1330	int err = 0;
1331
1332	skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1333			GFP_KERNEL);
1334	if (!skb)
1335		return -ENOBUFS;
1336
1337	if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, n->nlmsg_flags,
1338			 RTM_NEWACTION, 0, 0) <= 0) {
1339		NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1340		kfree_skb(skb);
1341		return -EINVAL;
1342	}
1343
1344	err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1345			     n->nlmsg_flags & NLM_F_ECHO);
1346	if (err > 0)
1347		err = 0;
1348	return err;
1349}
1350
1351static int tcf_action_add(struct net *net, struct nlattr *nla,
1352			  struct nlmsghdr *n, u32 portid, int ovr,
1353			  struct netlink_ext_ack *extack)
1354{
1355	size_t attr_size = 0;
1356	int loop, ret;
1357	struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
1358
1359	for (loop = 0; loop < 10; loop++) {
1360		ret = tcf_action_init(net, NULL, nla, NULL, NULL, ovr, 0,
1361				      actions, &attr_size, true, extack);
1362		if (ret != -EAGAIN)
1363			break;
1364	}
1365
1366	if (ret < 0)
1367		return ret;
1368	ret = tcf_add_notify(net, n, actions, portid, attr_size, extack);
1369	if (ovr)
1370		tcf_action_put_many(actions);
1371
1372	return ret;
1373}
1374
1375static u32 tcaa_root_flags_allowed = TCA_FLAG_LARGE_DUMP_ON;
1376static const struct nla_policy tcaa_policy[TCA_ROOT_MAX + 1] = {
1377	[TCA_ROOT_FLAGS] = { .type = NLA_BITFIELD32,
1378			     .validation_data = &tcaa_root_flags_allowed },
1379	[TCA_ROOT_TIME_DELTA]      = { .type = NLA_U32 },
1380};
1381
1382static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n,
1383			 struct netlink_ext_ack *extack)
1384{
1385	struct net *net = sock_net(skb->sk);
1386	struct nlattr *tca[TCA_ROOT_MAX + 1];
1387	u32 portid = skb ? NETLINK_CB(skb).portid : 0;
1388	int ret = 0, ovr = 0;
1389
1390	if ((n->nlmsg_type != RTM_GETACTION) &&
1391	    !netlink_capable(skb, CAP_NET_ADMIN))
1392		return -EPERM;
1393
1394	ret = nlmsg_parse_deprecated(n, sizeof(struct tcamsg), tca,
1395				     TCA_ROOT_MAX, NULL, extack);
1396	if (ret < 0)
1397		return ret;
1398
1399	if (tca[TCA_ACT_TAB] == NULL) {
1400		NL_SET_ERR_MSG(extack, "Netlink action attributes missing");
1401		return -EINVAL;
1402	}
1403
1404	/* n->nlmsg_flags & NLM_F_CREATE */
1405	switch (n->nlmsg_type) {
1406	case RTM_NEWACTION:
1407		/* we are going to assume all other flags
1408		 * imply create only if it doesn't exist
1409		 * Note that CREATE | EXCL implies that
1410		 * but since we want avoid ambiguity (eg when flags
1411		 * is zero) then just set this
1412		 */
1413		if (n->nlmsg_flags & NLM_F_REPLACE)
1414			ovr = 1;
1415		ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, portid, ovr,
1416				     extack);
1417		break;
1418	case RTM_DELACTION:
1419		ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
1420				    portid, RTM_DELACTION, extack);
1421		break;
1422	case RTM_GETACTION:
1423		ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
1424				    portid, RTM_GETACTION, extack);
1425		break;
1426	default:
1427		BUG();
1428	}
1429
1430	return ret;
1431}
1432
1433static struct nlattr *find_dump_kind(struct nlattr **nla)
1434{
1435	struct nlattr *tb1, *tb2[TCA_ACT_MAX + 1];
1436	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1437	struct nlattr *kind;
1438
1439	tb1 = nla[TCA_ACT_TAB];
1440	if (tb1 == NULL)
1441		return NULL;
1442
1443	if (nla_parse_deprecated(tb, TCA_ACT_MAX_PRIO, nla_data(tb1), NLMSG_ALIGN(nla_len(tb1)), NULL, NULL) < 0)
1444		return NULL;
1445
1446	if (tb[1] == NULL)
1447		return NULL;
1448	if (nla_parse_nested_deprecated(tb2, TCA_ACT_MAX, tb[1], tcf_action_policy, NULL) < 0)
1449		return NULL;
1450	kind = tb2[TCA_ACT_KIND];
1451
1452	return kind;
1453}
1454
1455static int tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
1456{
1457	struct net *net = sock_net(skb->sk);
1458	struct nlmsghdr *nlh;
1459	unsigned char *b = skb_tail_pointer(skb);
1460	struct nlattr *nest;
1461	struct tc_action_ops *a_o;
1462	int ret = 0;
1463	struct tcamsg *t = (struct tcamsg *) nlmsg_data(cb->nlh);
1464	struct nlattr *tb[TCA_ROOT_MAX + 1];
1465	struct nlattr *count_attr = NULL;
1466	unsigned long jiffy_since = 0;
1467	struct nlattr *kind = NULL;
1468	struct nla_bitfield32 bf;
1469	u32 msecs_since = 0;
1470	u32 act_count = 0;
1471
1472	ret = nlmsg_parse_deprecated(cb->nlh, sizeof(struct tcamsg), tb,
1473				     TCA_ROOT_MAX, tcaa_policy, cb->extack);
1474	if (ret < 0)
1475		return ret;
1476
1477	kind = find_dump_kind(tb);
1478	if (kind == NULL) {
1479		pr_info("tc_dump_action: action bad kind\n");
1480		return 0;
1481	}
1482
1483	a_o = tc_lookup_action(kind);
1484	if (a_o == NULL)
1485		return 0;
1486
1487	cb->args[2] = 0;
1488	if (tb[TCA_ROOT_FLAGS]) {
1489		bf = nla_get_bitfield32(tb[TCA_ROOT_FLAGS]);
1490		cb->args[2] = bf.value;
1491	}
1492
1493	if (tb[TCA_ROOT_TIME_DELTA]) {
1494		msecs_since = nla_get_u32(tb[TCA_ROOT_TIME_DELTA]);
1495	}
1496
1497	nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
1498			cb->nlh->nlmsg_type, sizeof(*t), 0);
1499	if (!nlh)
1500		goto out_module_put;
1501
1502	if (msecs_since)
1503		jiffy_since = jiffies - msecs_to_jiffies(msecs_since);
1504
1505	t = nlmsg_data(nlh);
1506	t->tca_family = AF_UNSPEC;
1507	t->tca__pad1 = 0;
1508	t->tca__pad2 = 0;
1509	cb->args[3] = jiffy_since;
1510	count_attr = nla_reserve(skb, TCA_ROOT_COUNT, sizeof(u32));
1511	if (!count_attr)
1512		goto out_module_put;
1513
1514	nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
1515	if (nest == NULL)
1516		goto out_module_put;
1517
1518	ret = a_o->walk(net, skb, cb, RTM_GETACTION, a_o, NULL);
1519	if (ret < 0)
1520		goto out_module_put;
1521
1522	if (ret > 0) {
1523		nla_nest_end(skb, nest);
1524		ret = skb->len;
1525		act_count = cb->args[1];
1526		memcpy(nla_data(count_attr), &act_count, sizeof(u32));
1527		cb->args[1] = 0;
1528	} else
1529		nlmsg_trim(skb, b);
1530
1531	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1532	if (NETLINK_CB(cb->skb).portid && ret)
1533		nlh->nlmsg_flags |= NLM_F_MULTI;
1534	module_put(a_o->owner);
1535	return skb->len;
1536
1537out_module_put:
1538	module_put(a_o->owner);
1539	nlmsg_trim(skb, b);
1540	return skb->len;
1541}
1542
1543static int __init tc_action_init(void)
1544{
1545	rtnl_register(PF_UNSPEC, RTM_NEWACTION, tc_ctl_action, NULL, 0);
1546	rtnl_register(PF_UNSPEC, RTM_DELACTION, tc_ctl_action, NULL, 0);
1547	rtnl_register(PF_UNSPEC, RTM_GETACTION, tc_ctl_action, tc_dump_action,
1548		      0);
1549
1550	return 0;
1551}
1552
1553subsys_initcall(tc_action_init);