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v5.4
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * net/sched/cls_api.c	Packet classifier API.
   4 *
   5 * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
   6 *
   7 * Changes:
   8 *
   9 * Eduardo J. Blanco <ejbs@netlabs.com.uy> :990222: kmod support
  10 */
  11
  12#include <linux/module.h>
  13#include <linux/types.h>
  14#include <linux/kernel.h>
  15#include <linux/string.h>
  16#include <linux/errno.h>
  17#include <linux/err.h>
  18#include <linux/skbuff.h>
  19#include <linux/init.h>
  20#include <linux/kmod.h>
  21#include <linux/slab.h>
  22#include <linux/idr.h>
  23#include <linux/rhashtable.h>
  24#include <linux/jhash.h>
 
 
  25#include <net/net_namespace.h>
  26#include <net/sock.h>
  27#include <net/netlink.h>
  28#include <net/pkt_sched.h>
  29#include <net/pkt_cls.h>
  30#include <net/tc_act/tc_pedit.h>
  31#include <net/tc_act/tc_mirred.h>
  32#include <net/tc_act/tc_vlan.h>
  33#include <net/tc_act/tc_tunnel_key.h>
  34#include <net/tc_act/tc_csum.h>
  35#include <net/tc_act/tc_gact.h>
  36#include <net/tc_act/tc_police.h>
  37#include <net/tc_act/tc_sample.h>
  38#include <net/tc_act/tc_skbedit.h>
  39#include <net/tc_act/tc_ct.h>
  40#include <net/tc_act/tc_mpls.h>
 
  41#include <net/flow_offload.h>
  42
  43extern const struct nla_policy rtm_tca_policy[TCA_MAX + 1];
  44
  45/* The list of all installed classifier types */
  46static LIST_HEAD(tcf_proto_base);
  47
  48/* Protects list of registered TC modules. It is pure SMP lock. */
  49static DEFINE_RWLOCK(cls_mod_lock);
  50
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  51static u32 destroy_obj_hashfn(const struct tcf_proto *tp)
  52{
  53	return jhash_3words(tp->chain->index, tp->prio,
  54			    (__force __u32)tp->protocol, 0);
  55}
  56
  57static void tcf_proto_signal_destroying(struct tcf_chain *chain,
  58					struct tcf_proto *tp)
  59{
  60	struct tcf_block *block = chain->block;
  61
  62	mutex_lock(&block->proto_destroy_lock);
  63	hash_add_rcu(block->proto_destroy_ht, &tp->destroy_ht_node,
  64		     destroy_obj_hashfn(tp));
  65	mutex_unlock(&block->proto_destroy_lock);
  66}
  67
  68static bool tcf_proto_cmp(const struct tcf_proto *tp1,
  69			  const struct tcf_proto *tp2)
  70{
  71	return tp1->chain->index == tp2->chain->index &&
  72	       tp1->prio == tp2->prio &&
  73	       tp1->protocol == tp2->protocol;
  74}
  75
  76static bool tcf_proto_exists_destroying(struct tcf_chain *chain,
  77					struct tcf_proto *tp)
  78{
  79	u32 hash = destroy_obj_hashfn(tp);
  80	struct tcf_proto *iter;
  81	bool found = false;
  82
  83	rcu_read_lock();
  84	hash_for_each_possible_rcu(chain->block->proto_destroy_ht, iter,
  85				   destroy_ht_node, hash) {
  86		if (tcf_proto_cmp(tp, iter)) {
  87			found = true;
  88			break;
  89		}
  90	}
  91	rcu_read_unlock();
  92
  93	return found;
  94}
  95
  96static void
  97tcf_proto_signal_destroyed(struct tcf_chain *chain, struct tcf_proto *tp)
  98{
  99	struct tcf_block *block = chain->block;
 100
 101	mutex_lock(&block->proto_destroy_lock);
 102	if (hash_hashed(&tp->destroy_ht_node))
 103		hash_del_rcu(&tp->destroy_ht_node);
 104	mutex_unlock(&block->proto_destroy_lock);
 105}
 106
 107/* Find classifier type by string name */
 108
 109static const struct tcf_proto_ops *__tcf_proto_lookup_ops(const char *kind)
 110{
 111	const struct tcf_proto_ops *t, *res = NULL;
 112
 113	if (kind) {
 114		read_lock(&cls_mod_lock);
 115		list_for_each_entry(t, &tcf_proto_base, head) {
 116			if (strcmp(kind, t->kind) == 0) {
 117				if (try_module_get(t->owner))
 118					res = t;
 119				break;
 120			}
 121		}
 122		read_unlock(&cls_mod_lock);
 123	}
 124	return res;
 125}
 126
 127static const struct tcf_proto_ops *
 128tcf_proto_lookup_ops(const char *kind, bool rtnl_held,
 129		     struct netlink_ext_ack *extack)
 130{
 131	const struct tcf_proto_ops *ops;
 132
 133	ops = __tcf_proto_lookup_ops(kind);
 134	if (ops)
 135		return ops;
 136#ifdef CONFIG_MODULES
 137	if (rtnl_held)
 138		rtnl_unlock();
 139	request_module("cls_%s", kind);
 140	if (rtnl_held)
 141		rtnl_lock();
 142	ops = __tcf_proto_lookup_ops(kind);
 143	/* We dropped the RTNL semaphore in order to perform
 144	 * the module load. So, even if we succeeded in loading
 145	 * the module we have to replay the request. We indicate
 146	 * this using -EAGAIN.
 147	 */
 148	if (ops) {
 149		module_put(ops->owner);
 150		return ERR_PTR(-EAGAIN);
 151	}
 152#endif
 153	NL_SET_ERR_MSG(extack, "TC classifier not found");
 154	return ERR_PTR(-ENOENT);
 155}
 156
 157/* Register(unregister) new classifier type */
 158
 159int register_tcf_proto_ops(struct tcf_proto_ops *ops)
 160{
 161	struct tcf_proto_ops *t;
 162	int rc = -EEXIST;
 163
 164	write_lock(&cls_mod_lock);
 165	list_for_each_entry(t, &tcf_proto_base, head)
 166		if (!strcmp(ops->kind, t->kind))
 167			goto out;
 168
 169	list_add_tail(&ops->head, &tcf_proto_base);
 170	rc = 0;
 171out:
 172	write_unlock(&cls_mod_lock);
 173	return rc;
 174}
 175EXPORT_SYMBOL(register_tcf_proto_ops);
 176
 177static struct workqueue_struct *tc_filter_wq;
 178
 179int unregister_tcf_proto_ops(struct tcf_proto_ops *ops)
 180{
 181	struct tcf_proto_ops *t;
 182	int rc = -ENOENT;
 183
 184	/* Wait for outstanding call_rcu()s, if any, from a
 185	 * tcf_proto_ops's destroy() handler.
 186	 */
 187	rcu_barrier();
 188	flush_workqueue(tc_filter_wq);
 189
 190	write_lock(&cls_mod_lock);
 191	list_for_each_entry(t, &tcf_proto_base, head) {
 192		if (t == ops) {
 193			list_del(&t->head);
 194			rc = 0;
 195			break;
 196		}
 197	}
 198	write_unlock(&cls_mod_lock);
 199	return rc;
 
 200}
 201EXPORT_SYMBOL(unregister_tcf_proto_ops);
 202
 203bool tcf_queue_work(struct rcu_work *rwork, work_func_t func)
 204{
 205	INIT_RCU_WORK(rwork, func);
 206	return queue_rcu_work(tc_filter_wq, rwork);
 207}
 208EXPORT_SYMBOL(tcf_queue_work);
 209
 210/* Select new prio value from the range, managed by kernel. */
 211
 212static inline u32 tcf_auto_prio(struct tcf_proto *tp)
 213{
 214	u32 first = TC_H_MAKE(0xC0000000U, 0U);
 215
 216	if (tp)
 217		first = tp->prio - 1;
 218
 219	return TC_H_MAJ(first);
 220}
 221
 222static bool tcf_proto_check_kind(struct nlattr *kind, char *name)
 223{
 224	if (kind)
 225		return nla_strlcpy(name, kind, IFNAMSIZ) >= IFNAMSIZ;
 226	memset(name, 0, IFNAMSIZ);
 227	return false;
 228}
 229
 230static bool tcf_proto_is_unlocked(const char *kind)
 231{
 232	const struct tcf_proto_ops *ops;
 233	bool ret;
 234
 235	if (strlen(kind) == 0)
 236		return false;
 237
 238	ops = tcf_proto_lookup_ops(kind, false, NULL);
 239	/* On error return false to take rtnl lock. Proto lookup/create
 240	 * functions will perform lookup again and properly handle errors.
 241	 */
 242	if (IS_ERR(ops))
 243		return false;
 244
 245	ret = !!(ops->flags & TCF_PROTO_OPS_DOIT_UNLOCKED);
 246	module_put(ops->owner);
 247	return ret;
 248}
 249
 250static struct tcf_proto *tcf_proto_create(const char *kind, u32 protocol,
 251					  u32 prio, struct tcf_chain *chain,
 252					  bool rtnl_held,
 253					  struct netlink_ext_ack *extack)
 254{
 255	struct tcf_proto *tp;
 256	int err;
 257
 258	tp = kzalloc(sizeof(*tp), GFP_KERNEL);
 259	if (!tp)
 260		return ERR_PTR(-ENOBUFS);
 261
 262	tp->ops = tcf_proto_lookup_ops(kind, rtnl_held, extack);
 263	if (IS_ERR(tp->ops)) {
 264		err = PTR_ERR(tp->ops);
 265		goto errout;
 266	}
 267	tp->classify = tp->ops->classify;
 268	tp->protocol = protocol;
 269	tp->prio = prio;
 270	tp->chain = chain;
 271	spin_lock_init(&tp->lock);
 272	refcount_set(&tp->refcnt, 1);
 273
 274	err = tp->ops->init(tp);
 275	if (err) {
 276		module_put(tp->ops->owner);
 277		goto errout;
 278	}
 279	return tp;
 280
 281errout:
 282	kfree(tp);
 283	return ERR_PTR(err);
 284}
 285
 286static void tcf_proto_get(struct tcf_proto *tp)
 287{
 288	refcount_inc(&tp->refcnt);
 289}
 290
 291static void tcf_chain_put(struct tcf_chain *chain);
 292
 293static void tcf_proto_destroy(struct tcf_proto *tp, bool rtnl_held,
 294			      bool sig_destroy, struct netlink_ext_ack *extack)
 295{
 296	tp->ops->destroy(tp, rtnl_held, extack);
 297	if (sig_destroy)
 298		tcf_proto_signal_destroyed(tp->chain, tp);
 299	tcf_chain_put(tp->chain);
 300	module_put(tp->ops->owner);
 301	kfree_rcu(tp, rcu);
 302}
 303
 304static void tcf_proto_put(struct tcf_proto *tp, bool rtnl_held,
 305			  struct netlink_ext_ack *extack)
 306{
 307	if (refcount_dec_and_test(&tp->refcnt))
 308		tcf_proto_destroy(tp, rtnl_held, true, extack);
 309}
 310
 311static int walker_check_empty(struct tcf_proto *tp, void *fh,
 312			      struct tcf_walker *arg)
 313{
 314	if (fh) {
 315		arg->nonempty = true;
 316		return -1;
 317	}
 318	return 0;
 319}
 320
 321static bool tcf_proto_is_empty(struct tcf_proto *tp, bool rtnl_held)
 322{
 323	struct tcf_walker walker = { .fn = walker_check_empty, };
 324
 325	if (tp->ops->walk) {
 326		tp->ops->walk(tp, &walker, rtnl_held);
 327		return !walker.nonempty;
 328	}
 329	return true;
 330}
 331
 332static bool tcf_proto_check_delete(struct tcf_proto *tp, bool rtnl_held)
 333{
 334	spin_lock(&tp->lock);
 335	if (tcf_proto_is_empty(tp, rtnl_held))
 336		tp->deleting = true;
 337	spin_unlock(&tp->lock);
 338	return tp->deleting;
 339}
 340
 341static void tcf_proto_mark_delete(struct tcf_proto *tp)
 342{
 343	spin_lock(&tp->lock);
 344	tp->deleting = true;
 345	spin_unlock(&tp->lock);
 346}
 347
 348static bool tcf_proto_is_deleting(struct tcf_proto *tp)
 349{
 350	bool deleting;
 351
 352	spin_lock(&tp->lock);
 353	deleting = tp->deleting;
 354	spin_unlock(&tp->lock);
 355
 356	return deleting;
 357}
 358
 359#define ASSERT_BLOCK_LOCKED(block)					\
 360	lockdep_assert_held(&(block)->lock)
 361
 362struct tcf_filter_chain_list_item {
 363	struct list_head list;
 364	tcf_chain_head_change_t *chain_head_change;
 365	void *chain_head_change_priv;
 366};
 367
 368static struct tcf_chain *tcf_chain_create(struct tcf_block *block,
 369					  u32 chain_index)
 370{
 371	struct tcf_chain *chain;
 372
 373	ASSERT_BLOCK_LOCKED(block);
 374
 375	chain = kzalloc(sizeof(*chain), GFP_KERNEL);
 376	if (!chain)
 377		return NULL;
 378	list_add_tail(&chain->list, &block->chain_list);
 379	mutex_init(&chain->filter_chain_lock);
 380	chain->block = block;
 381	chain->index = chain_index;
 382	chain->refcnt = 1;
 383	if (!chain->index)
 384		block->chain0.chain = chain;
 385	return chain;
 386}
 387
 388static void tcf_chain_head_change_item(struct tcf_filter_chain_list_item *item,
 389				       struct tcf_proto *tp_head)
 390{
 391	if (item->chain_head_change)
 392		item->chain_head_change(tp_head, item->chain_head_change_priv);
 393}
 394
 395static void tcf_chain0_head_change(struct tcf_chain *chain,
 396				   struct tcf_proto *tp_head)
 397{
 398	struct tcf_filter_chain_list_item *item;
 399	struct tcf_block *block = chain->block;
 400
 401	if (chain->index)
 402		return;
 403
 404	mutex_lock(&block->lock);
 405	list_for_each_entry(item, &block->chain0.filter_chain_list, list)
 406		tcf_chain_head_change_item(item, tp_head);
 407	mutex_unlock(&block->lock);
 408}
 409
 410/* Returns true if block can be safely freed. */
 411
 412static bool tcf_chain_detach(struct tcf_chain *chain)
 413{
 414	struct tcf_block *block = chain->block;
 415
 416	ASSERT_BLOCK_LOCKED(block);
 417
 418	list_del(&chain->list);
 419	if (!chain->index)
 420		block->chain0.chain = NULL;
 421
 422	if (list_empty(&block->chain_list) &&
 423	    refcount_read(&block->refcnt) == 0)
 424		return true;
 425
 426	return false;
 427}
 428
 429static void tcf_block_destroy(struct tcf_block *block)
 430{
 431	mutex_destroy(&block->lock);
 432	mutex_destroy(&block->proto_destroy_lock);
 
 433	kfree_rcu(block, rcu);
 434}
 435
 436static void tcf_chain_destroy(struct tcf_chain *chain, bool free_block)
 437{
 438	struct tcf_block *block = chain->block;
 439
 440	mutex_destroy(&chain->filter_chain_lock);
 441	kfree_rcu(chain, rcu);
 442	if (free_block)
 443		tcf_block_destroy(block);
 444}
 445
 446static void tcf_chain_hold(struct tcf_chain *chain)
 447{
 448	ASSERT_BLOCK_LOCKED(chain->block);
 449
 450	++chain->refcnt;
 451}
 452
 453static bool tcf_chain_held_by_acts_only(struct tcf_chain *chain)
 454{
 455	ASSERT_BLOCK_LOCKED(chain->block);
 456
 457	/* In case all the references are action references, this
 458	 * chain should not be shown to the user.
 459	 */
 460	return chain->refcnt == chain->action_refcnt;
 461}
 462
 463static struct tcf_chain *tcf_chain_lookup(struct tcf_block *block,
 464					  u32 chain_index)
 465{
 466	struct tcf_chain *chain;
 467
 468	ASSERT_BLOCK_LOCKED(block);
 469
 470	list_for_each_entry(chain, &block->chain_list, list) {
 471		if (chain->index == chain_index)
 472			return chain;
 473	}
 474	return NULL;
 475}
 476
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 477static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb,
 478			   u32 seq, u16 flags, int event, bool unicast);
 
 479
 480static struct tcf_chain *__tcf_chain_get(struct tcf_block *block,
 481					 u32 chain_index, bool create,
 482					 bool by_act)
 483{
 484	struct tcf_chain *chain = NULL;
 485	bool is_first_reference;
 486
 487	mutex_lock(&block->lock);
 488	chain = tcf_chain_lookup(block, chain_index);
 489	if (chain) {
 490		tcf_chain_hold(chain);
 491	} else {
 492		if (!create)
 493			goto errout;
 494		chain = tcf_chain_create(block, chain_index);
 495		if (!chain)
 496			goto errout;
 497	}
 498
 499	if (by_act)
 500		++chain->action_refcnt;
 501	is_first_reference = chain->refcnt - chain->action_refcnt == 1;
 502	mutex_unlock(&block->lock);
 503
 504	/* Send notification only in case we got the first
 505	 * non-action reference. Until then, the chain acts only as
 506	 * a placeholder for actions pointing to it and user ought
 507	 * not know about them.
 508	 */
 509	if (is_first_reference && !by_act)
 510		tc_chain_notify(chain, NULL, 0, NLM_F_CREATE | NLM_F_EXCL,
 511				RTM_NEWCHAIN, false);
 512
 513	return chain;
 514
 515errout:
 516	mutex_unlock(&block->lock);
 517	return chain;
 518}
 519
 520static struct tcf_chain *tcf_chain_get(struct tcf_block *block, u32 chain_index,
 521				       bool create)
 522{
 523	return __tcf_chain_get(block, chain_index, create, false);
 524}
 525
 526struct tcf_chain *tcf_chain_get_by_act(struct tcf_block *block, u32 chain_index)
 527{
 528	return __tcf_chain_get(block, chain_index, true, true);
 529}
 530EXPORT_SYMBOL(tcf_chain_get_by_act);
 531
 532static void tc_chain_tmplt_del(const struct tcf_proto_ops *tmplt_ops,
 533			       void *tmplt_priv);
 534static int tc_chain_notify_delete(const struct tcf_proto_ops *tmplt_ops,
 535				  void *tmplt_priv, u32 chain_index,
 536				  struct tcf_block *block, struct sk_buff *oskb,
 537				  u32 seq, u16 flags, bool unicast);
 538
 539static void __tcf_chain_put(struct tcf_chain *chain, bool by_act,
 540			    bool explicitly_created)
 541{
 542	struct tcf_block *block = chain->block;
 543	const struct tcf_proto_ops *tmplt_ops;
 
 544	bool free_block = false;
 545	unsigned int refcnt;
 546	void *tmplt_priv;
 547
 548	mutex_lock(&block->lock);
 549	if (explicitly_created) {
 550		if (!chain->explicitly_created) {
 551			mutex_unlock(&block->lock);
 552			return;
 553		}
 554		chain->explicitly_created = false;
 555	}
 556
 557	if (by_act)
 558		chain->action_refcnt--;
 559
 560	/* tc_chain_notify_delete can't be called while holding block lock.
 561	 * However, when block is unlocked chain can be changed concurrently, so
 562	 * save these to temporary variables.
 563	 */
 564	refcnt = --chain->refcnt;
 
 565	tmplt_ops = chain->tmplt_ops;
 566	tmplt_priv = chain->tmplt_priv;
 567
 568	/* The last dropped non-action reference will trigger notification. */
 569	if (refcnt - chain->action_refcnt == 0 && !by_act) {
 570		tc_chain_notify_delete(tmplt_ops, tmplt_priv, chain->index,
 571				       block, NULL, 0, 0, false);
 572		/* Last reference to chain, no need to lock. */
 573		chain->flushing = false;
 574	}
 575
 576	if (refcnt == 0)
 577		free_block = tcf_chain_detach(chain);
 578	mutex_unlock(&block->lock);
 579
 580	if (refcnt == 0) {
 581		tc_chain_tmplt_del(tmplt_ops, tmplt_priv);
 582		tcf_chain_destroy(chain, free_block);
 583	}
 584}
 585
 586static void tcf_chain_put(struct tcf_chain *chain)
 587{
 588	__tcf_chain_put(chain, false, false);
 589}
 590
 591void tcf_chain_put_by_act(struct tcf_chain *chain)
 592{
 593	__tcf_chain_put(chain, true, false);
 594}
 595EXPORT_SYMBOL(tcf_chain_put_by_act);
 596
 597static void tcf_chain_put_explicitly_created(struct tcf_chain *chain)
 598{
 599	__tcf_chain_put(chain, false, true);
 600}
 601
 602static void tcf_chain_flush(struct tcf_chain *chain, bool rtnl_held)
 603{
 604	struct tcf_proto *tp, *tp_next;
 605
 606	mutex_lock(&chain->filter_chain_lock);
 607	tp = tcf_chain_dereference(chain->filter_chain, chain);
 608	while (tp) {
 609		tp_next = rcu_dereference_protected(tp->next, 1);
 610		tcf_proto_signal_destroying(chain, tp);
 611		tp = tp_next;
 612	}
 613	tp = tcf_chain_dereference(chain->filter_chain, chain);
 614	RCU_INIT_POINTER(chain->filter_chain, NULL);
 615	tcf_chain0_head_change(chain, NULL);
 616	chain->flushing = true;
 617	mutex_unlock(&chain->filter_chain_lock);
 618
 619	while (tp) {
 620		tp_next = rcu_dereference_protected(tp->next, 1);
 621		tcf_proto_put(tp, rtnl_held, NULL);
 622		tp = tp_next;
 623	}
 624}
 625
 626static int tcf_block_setup(struct tcf_block *block,
 627			   struct flow_block_offload *bo);
 628
 629static void tc_indr_block_ing_cmd(struct net_device *dev,
 630				  struct tcf_block *block,
 631				  flow_indr_block_bind_cb_t *cb,
 632				  void *cb_priv,
 633				  enum flow_block_command command)
 634{
 635	struct flow_block_offload bo = {
 636		.command	= command,
 637		.binder_type	= FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS,
 638		.net		= dev_net(dev),
 639		.block_shared	= tcf_block_non_null_shared(block),
 640	};
 641	INIT_LIST_HEAD(&bo.cb_list);
 642
 643	if (!block)
 644		return;
 645
 646	bo.block = &block->flow_block;
 647
 648	down_write(&block->cb_lock);
 649	cb(dev, cb_priv, TC_SETUP_BLOCK, &bo);
 650
 651	tcf_block_setup(block, &bo);
 652	up_write(&block->cb_lock);
 653}
 654
 655static struct tcf_block *tc_dev_ingress_block(struct net_device *dev)
 656{
 657	const struct Qdisc_class_ops *cops;
 658	struct Qdisc *qdisc;
 659
 660	if (!dev_ingress_queue(dev))
 661		return NULL;
 662
 663	qdisc = dev_ingress_queue(dev)->qdisc_sleeping;
 664	if (!qdisc)
 665		return NULL;
 666
 667	cops = qdisc->ops->cl_ops;
 668	if (!cops)
 669		return NULL;
 670
 671	if (!cops->tcf_block)
 672		return NULL;
 673
 674	return cops->tcf_block(qdisc, TC_H_MIN_INGRESS, NULL);
 675}
 676
 677static void tc_indr_block_get_and_ing_cmd(struct net_device *dev,
 678					  flow_indr_block_bind_cb_t *cb,
 679					  void *cb_priv,
 680					  enum flow_block_command command)
 681{
 682	struct tcf_block *block = tc_dev_ingress_block(dev);
 683
 684	tc_indr_block_ing_cmd(dev, block, cb, cb_priv, command);
 685}
 686
 687static void tc_indr_block_call(struct tcf_block *block,
 688			       struct net_device *dev,
 689			       struct tcf_block_ext_info *ei,
 690			       enum flow_block_command command,
 691			       struct netlink_ext_ack *extack)
 692{
 693	struct flow_block_offload bo = {
 694		.command	= command,
 695		.binder_type	= ei->binder_type,
 696		.net		= dev_net(dev),
 697		.block		= &block->flow_block,
 698		.block_shared	= tcf_block_shared(block),
 699		.extack		= extack,
 700	};
 701	INIT_LIST_HEAD(&bo.cb_list);
 702
 703	flow_indr_block_call(dev, &bo, command);
 704	tcf_block_setup(block, &bo);
 
 
 
 
 
 
 
 
 
 705}
 706
 707static bool tcf_block_offload_in_use(struct tcf_block *block)
 708{
 709	return atomic_read(&block->offloadcnt);
 710}
 711
 712static int tcf_block_offload_cmd(struct tcf_block *block,
 713				 struct net_device *dev,
 714				 struct tcf_block_ext_info *ei,
 715				 enum flow_block_command command,
 716				 struct netlink_ext_ack *extack)
 717{
 718	struct flow_block_offload bo = {};
 719	int err;
 720
 721	bo.net = dev_net(dev);
 722	bo.command = command;
 723	bo.binder_type = ei->binder_type;
 724	bo.block = &block->flow_block;
 725	bo.block_shared = tcf_block_shared(block);
 726	bo.extack = extack;
 727	INIT_LIST_HEAD(&bo.cb_list);
 728
 729	err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_BLOCK, &bo);
 730	if (err < 0)
 731		return err;
 
 
 
 
 
 
 
 
 
 732
 733	return tcf_block_setup(block, &bo);
 
 
 
 
 734}
 735
 736static int tcf_block_offload_bind(struct tcf_block *block, struct Qdisc *q,
 737				  struct tcf_block_ext_info *ei,
 738				  struct netlink_ext_ack *extack)
 739{
 740	struct net_device *dev = q->dev_queue->dev;
 741	int err;
 742
 743	down_write(&block->cb_lock);
 744	if (!dev->netdev_ops->ndo_setup_tc)
 745		goto no_offload_dev_inc;
 746
 747	/* If tc offload feature is disabled and the block we try to bind
 748	 * to already has some offloaded filters, forbid to bind.
 749	 */
 750	if (!tc_can_offload(dev) && tcf_block_offload_in_use(block)) {
 
 
 751		NL_SET_ERR_MSG(extack, "Bind to offloaded block failed as dev has offload disabled");
 752		err = -EOPNOTSUPP;
 753		goto err_unlock;
 754	}
 755
 756	err = tcf_block_offload_cmd(block, dev, ei, FLOW_BLOCK_BIND, extack);
 757	if (err == -EOPNOTSUPP)
 758		goto no_offload_dev_inc;
 759	if (err)
 760		goto err_unlock;
 761
 762	tc_indr_block_call(block, dev, ei, FLOW_BLOCK_BIND, extack);
 763	up_write(&block->cb_lock);
 764	return 0;
 765
 766no_offload_dev_inc:
 767	if (tcf_block_offload_in_use(block)) {
 768		err = -EOPNOTSUPP;
 769		goto err_unlock;
 770	}
 771	err = 0;
 772	block->nooffloaddevcnt++;
 773	tc_indr_block_call(block, dev, ei, FLOW_BLOCK_BIND, extack);
 774err_unlock:
 775	up_write(&block->cb_lock);
 776	return err;
 777}
 778
 779static void tcf_block_offload_unbind(struct tcf_block *block, struct Qdisc *q,
 780				     struct tcf_block_ext_info *ei)
 781{
 782	struct net_device *dev = q->dev_queue->dev;
 783	int err;
 784
 785	down_write(&block->cb_lock);
 786	tc_indr_block_call(block, dev, ei, FLOW_BLOCK_UNBIND, NULL);
 787
 788	if (!dev->netdev_ops->ndo_setup_tc)
 789		goto no_offload_dev_dec;
 790	err = tcf_block_offload_cmd(block, dev, ei, FLOW_BLOCK_UNBIND, NULL);
 791	if (err == -EOPNOTSUPP)
 792		goto no_offload_dev_dec;
 793	up_write(&block->cb_lock);
 794	return;
 795
 796no_offload_dev_dec:
 797	WARN_ON(block->nooffloaddevcnt-- == 0);
 798	up_write(&block->cb_lock);
 799}
 800
 801static int
 802tcf_chain0_head_change_cb_add(struct tcf_block *block,
 803			      struct tcf_block_ext_info *ei,
 804			      struct netlink_ext_ack *extack)
 805{
 806	struct tcf_filter_chain_list_item *item;
 807	struct tcf_chain *chain0;
 808
 809	item = kmalloc(sizeof(*item), GFP_KERNEL);
 810	if (!item) {
 811		NL_SET_ERR_MSG(extack, "Memory allocation for head change callback item failed");
 812		return -ENOMEM;
 813	}
 814	item->chain_head_change = ei->chain_head_change;
 815	item->chain_head_change_priv = ei->chain_head_change_priv;
 816
 817	mutex_lock(&block->lock);
 818	chain0 = block->chain0.chain;
 819	if (chain0)
 820		tcf_chain_hold(chain0);
 821	else
 822		list_add(&item->list, &block->chain0.filter_chain_list);
 823	mutex_unlock(&block->lock);
 824
 825	if (chain0) {
 826		struct tcf_proto *tp_head;
 827
 828		mutex_lock(&chain0->filter_chain_lock);
 829
 830		tp_head = tcf_chain_dereference(chain0->filter_chain, chain0);
 831		if (tp_head)
 832			tcf_chain_head_change_item(item, tp_head);
 833
 834		mutex_lock(&block->lock);
 835		list_add(&item->list, &block->chain0.filter_chain_list);
 836		mutex_unlock(&block->lock);
 837
 838		mutex_unlock(&chain0->filter_chain_lock);
 839		tcf_chain_put(chain0);
 840	}
 841
 842	return 0;
 843}
 844
 845static void
 846tcf_chain0_head_change_cb_del(struct tcf_block *block,
 847			      struct tcf_block_ext_info *ei)
 848{
 849	struct tcf_filter_chain_list_item *item;
 850
 851	mutex_lock(&block->lock);
 852	list_for_each_entry(item, &block->chain0.filter_chain_list, list) {
 853		if ((!ei->chain_head_change && !ei->chain_head_change_priv) ||
 854		    (item->chain_head_change == ei->chain_head_change &&
 855		     item->chain_head_change_priv == ei->chain_head_change_priv)) {
 856			if (block->chain0.chain)
 857				tcf_chain_head_change_item(item, NULL);
 858			list_del(&item->list);
 859			mutex_unlock(&block->lock);
 860
 861			kfree(item);
 862			return;
 863		}
 864	}
 865	mutex_unlock(&block->lock);
 866	WARN_ON(1);
 867}
 868
 869struct tcf_net {
 870	spinlock_t idr_lock; /* Protects idr */
 871	struct idr idr;
 872};
 873
 874static unsigned int tcf_net_id;
 875
 876static int tcf_block_insert(struct tcf_block *block, struct net *net,
 877			    struct netlink_ext_ack *extack)
 878{
 879	struct tcf_net *tn = net_generic(net, tcf_net_id);
 880	int err;
 881
 882	idr_preload(GFP_KERNEL);
 883	spin_lock(&tn->idr_lock);
 884	err = idr_alloc_u32(&tn->idr, block, &block->index, block->index,
 885			    GFP_NOWAIT);
 886	spin_unlock(&tn->idr_lock);
 887	idr_preload_end();
 888
 889	return err;
 890}
 891
 892static void tcf_block_remove(struct tcf_block *block, struct net *net)
 893{
 894	struct tcf_net *tn = net_generic(net, tcf_net_id);
 895
 896	spin_lock(&tn->idr_lock);
 897	idr_remove(&tn->idr, block->index);
 898	spin_unlock(&tn->idr_lock);
 899}
 900
 901static struct tcf_block *tcf_block_create(struct net *net, struct Qdisc *q,
 902					  u32 block_index,
 903					  struct netlink_ext_ack *extack)
 904{
 905	struct tcf_block *block;
 906
 907	block = kzalloc(sizeof(*block), GFP_KERNEL);
 908	if (!block) {
 909		NL_SET_ERR_MSG(extack, "Memory allocation for block failed");
 910		return ERR_PTR(-ENOMEM);
 911	}
 912	mutex_init(&block->lock);
 913	mutex_init(&block->proto_destroy_lock);
 914	init_rwsem(&block->cb_lock);
 915	flow_block_init(&block->flow_block);
 916	INIT_LIST_HEAD(&block->chain_list);
 917	INIT_LIST_HEAD(&block->owner_list);
 918	INIT_LIST_HEAD(&block->chain0.filter_chain_list);
 919
 920	refcount_set(&block->refcnt, 1);
 921	block->net = net;
 922	block->index = block_index;
 
 923
 924	/* Don't store q pointer for blocks which are shared */
 925	if (!tcf_block_shared(block))
 926		block->q = q;
 927	return block;
 928}
 929
 930static struct tcf_block *tcf_block_lookup(struct net *net, u32 block_index)
 931{
 932	struct tcf_net *tn = net_generic(net, tcf_net_id);
 933
 934	return idr_find(&tn->idr, block_index);
 935}
 
 936
 937static struct tcf_block *tcf_block_refcnt_get(struct net *net, u32 block_index)
 938{
 939	struct tcf_block *block;
 940
 941	rcu_read_lock();
 942	block = tcf_block_lookup(net, block_index);
 943	if (block && !refcount_inc_not_zero(&block->refcnt))
 944		block = NULL;
 945	rcu_read_unlock();
 946
 947	return block;
 948}
 949
 950static struct tcf_chain *
 951__tcf_get_next_chain(struct tcf_block *block, struct tcf_chain *chain)
 952{
 953	mutex_lock(&block->lock);
 954	if (chain)
 955		chain = list_is_last(&chain->list, &block->chain_list) ?
 956			NULL : list_next_entry(chain, list);
 957	else
 958		chain = list_first_entry_or_null(&block->chain_list,
 959						 struct tcf_chain, list);
 960
 961	/* skip all action-only chains */
 962	while (chain && tcf_chain_held_by_acts_only(chain))
 963		chain = list_is_last(&chain->list, &block->chain_list) ?
 964			NULL : list_next_entry(chain, list);
 965
 966	if (chain)
 967		tcf_chain_hold(chain);
 968	mutex_unlock(&block->lock);
 969
 970	return chain;
 971}
 972
 973/* Function to be used by all clients that want to iterate over all chains on
 974 * block. It properly obtains block->lock and takes reference to chain before
 975 * returning it. Users of this function must be tolerant to concurrent chain
 976 * insertion/deletion or ensure that no concurrent chain modification is
 977 * possible. Note that all netlink dump callbacks cannot guarantee to provide
 978 * consistent dump because rtnl lock is released each time skb is filled with
 979 * data and sent to user-space.
 980 */
 981
 982struct tcf_chain *
 983tcf_get_next_chain(struct tcf_block *block, struct tcf_chain *chain)
 984{
 985	struct tcf_chain *chain_next = __tcf_get_next_chain(block, chain);
 986
 987	if (chain)
 988		tcf_chain_put(chain);
 989
 990	return chain_next;
 991}
 992EXPORT_SYMBOL(tcf_get_next_chain);
 993
 994static struct tcf_proto *
 995__tcf_get_next_proto(struct tcf_chain *chain, struct tcf_proto *tp)
 996{
 997	u32 prio = 0;
 998
 999	ASSERT_RTNL();
1000	mutex_lock(&chain->filter_chain_lock);
1001
1002	if (!tp) {
1003		tp = tcf_chain_dereference(chain->filter_chain, chain);
1004	} else if (tcf_proto_is_deleting(tp)) {
1005		/* 'deleting' flag is set and chain->filter_chain_lock was
1006		 * unlocked, which means next pointer could be invalid. Restart
1007		 * search.
1008		 */
1009		prio = tp->prio + 1;
1010		tp = tcf_chain_dereference(chain->filter_chain, chain);
1011
1012		for (; tp; tp = tcf_chain_dereference(tp->next, chain))
1013			if (!tp->deleting && tp->prio >= prio)
1014				break;
1015	} else {
1016		tp = tcf_chain_dereference(tp->next, chain);
1017	}
1018
1019	if (tp)
1020		tcf_proto_get(tp);
1021
1022	mutex_unlock(&chain->filter_chain_lock);
1023
1024	return tp;
1025}
1026
1027/* Function to be used by all clients that want to iterate over all tp's on
1028 * chain. Users of this function must be tolerant to concurrent tp
1029 * insertion/deletion or ensure that no concurrent chain modification is
1030 * possible. Note that all netlink dump callbacks cannot guarantee to provide
1031 * consistent dump because rtnl lock is released each time skb is filled with
1032 * data and sent to user-space.
1033 */
1034
1035struct tcf_proto *
1036tcf_get_next_proto(struct tcf_chain *chain, struct tcf_proto *tp,
1037		   bool rtnl_held)
1038{
1039	struct tcf_proto *tp_next = __tcf_get_next_proto(chain, tp);
1040
1041	if (tp)
1042		tcf_proto_put(tp, rtnl_held, NULL);
1043
1044	return tp_next;
1045}
1046EXPORT_SYMBOL(tcf_get_next_proto);
1047
1048static void tcf_block_flush_all_chains(struct tcf_block *block, bool rtnl_held)
1049{
1050	struct tcf_chain *chain;
1051
1052	/* Last reference to block. At this point chains cannot be added or
1053	 * removed concurrently.
1054	 */
1055	for (chain = tcf_get_next_chain(block, NULL);
1056	     chain;
1057	     chain = tcf_get_next_chain(block, chain)) {
1058		tcf_chain_put_explicitly_created(chain);
1059		tcf_chain_flush(chain, rtnl_held);
1060	}
1061}
1062
1063/* Lookup Qdisc and increments its reference counter.
1064 * Set parent, if necessary.
1065 */
1066
1067static int __tcf_qdisc_find(struct net *net, struct Qdisc **q,
1068			    u32 *parent, int ifindex, bool rtnl_held,
1069			    struct netlink_ext_ack *extack)
1070{
1071	const struct Qdisc_class_ops *cops;
1072	struct net_device *dev;
1073	int err = 0;
1074
1075	if (ifindex == TCM_IFINDEX_MAGIC_BLOCK)
1076		return 0;
1077
1078	rcu_read_lock();
1079
1080	/* Find link */
1081	dev = dev_get_by_index_rcu(net, ifindex);
1082	if (!dev) {
1083		rcu_read_unlock();
1084		return -ENODEV;
1085	}
1086
1087	/* Find qdisc */
1088	if (!*parent) {
1089		*q = dev->qdisc;
1090		*parent = (*q)->handle;
1091	} else {
1092		*q = qdisc_lookup_rcu(dev, TC_H_MAJ(*parent));
1093		if (!*q) {
1094			NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists");
1095			err = -EINVAL;
1096			goto errout_rcu;
1097		}
1098	}
1099
1100	*q = qdisc_refcount_inc_nz(*q);
1101	if (!*q) {
1102		NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists");
1103		err = -EINVAL;
1104		goto errout_rcu;
1105	}
1106
1107	/* Is it classful? */
1108	cops = (*q)->ops->cl_ops;
1109	if (!cops) {
1110		NL_SET_ERR_MSG(extack, "Qdisc not classful");
1111		err = -EINVAL;
1112		goto errout_qdisc;
1113	}
1114
1115	if (!cops->tcf_block) {
1116		NL_SET_ERR_MSG(extack, "Class doesn't support blocks");
1117		err = -EOPNOTSUPP;
1118		goto errout_qdisc;
1119	}
1120
1121errout_rcu:
1122	/* At this point we know that qdisc is not noop_qdisc,
1123	 * which means that qdisc holds a reference to net_device
1124	 * and we hold a reference to qdisc, so it is safe to release
1125	 * rcu read lock.
1126	 */
1127	rcu_read_unlock();
1128	return err;
1129
1130errout_qdisc:
1131	rcu_read_unlock();
1132
1133	if (rtnl_held)
1134		qdisc_put(*q);
1135	else
1136		qdisc_put_unlocked(*q);
1137	*q = NULL;
1138
1139	return err;
1140}
1141
1142static int __tcf_qdisc_cl_find(struct Qdisc *q, u32 parent, unsigned long *cl,
1143			       int ifindex, struct netlink_ext_ack *extack)
1144{
1145	if (ifindex == TCM_IFINDEX_MAGIC_BLOCK)
1146		return 0;
1147
1148	/* Do we search for filter, attached to class? */
1149	if (TC_H_MIN(parent)) {
1150		const struct Qdisc_class_ops *cops = q->ops->cl_ops;
1151
1152		*cl = cops->find(q, parent);
1153		if (*cl == 0) {
1154			NL_SET_ERR_MSG(extack, "Specified class doesn't exist");
1155			return -ENOENT;
1156		}
1157	}
1158
1159	return 0;
1160}
1161
1162static struct tcf_block *__tcf_block_find(struct net *net, struct Qdisc *q,
1163					  unsigned long cl, int ifindex,
1164					  u32 block_index,
1165					  struct netlink_ext_ack *extack)
1166{
1167	struct tcf_block *block;
1168
1169	if (ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
1170		block = tcf_block_refcnt_get(net, block_index);
1171		if (!block) {
1172			NL_SET_ERR_MSG(extack, "Block of given index was not found");
1173			return ERR_PTR(-EINVAL);
1174		}
1175	} else {
1176		const struct Qdisc_class_ops *cops = q->ops->cl_ops;
1177
1178		block = cops->tcf_block(q, cl, extack);
1179		if (!block)
1180			return ERR_PTR(-EINVAL);
1181
1182		if (tcf_block_shared(block)) {
1183			NL_SET_ERR_MSG(extack, "This filter block is shared. Please use the block index to manipulate the filters");
1184			return ERR_PTR(-EOPNOTSUPP);
1185		}
1186
1187		/* Always take reference to block in order to support execution
1188		 * of rules update path of cls API without rtnl lock. Caller
1189		 * must release block when it is finished using it. 'if' block
1190		 * of this conditional obtain reference to block by calling
1191		 * tcf_block_refcnt_get().
1192		 */
1193		refcount_inc(&block->refcnt);
1194	}
1195
1196	return block;
1197}
1198
1199static void __tcf_block_put(struct tcf_block *block, struct Qdisc *q,
1200			    struct tcf_block_ext_info *ei, bool rtnl_held)
1201{
1202	if (refcount_dec_and_mutex_lock(&block->refcnt, &block->lock)) {
1203		/* Flushing/putting all chains will cause the block to be
1204		 * deallocated when last chain is freed. However, if chain_list
1205		 * is empty, block has to be manually deallocated. After block
1206		 * reference counter reached 0, it is no longer possible to
1207		 * increment it or add new chains to block.
1208		 */
1209		bool free_block = list_empty(&block->chain_list);
1210
1211		mutex_unlock(&block->lock);
1212		if (tcf_block_shared(block))
1213			tcf_block_remove(block, block->net);
1214
1215		if (q)
1216			tcf_block_offload_unbind(block, q, ei);
1217
1218		if (free_block)
1219			tcf_block_destroy(block);
1220		else
1221			tcf_block_flush_all_chains(block, rtnl_held);
1222	} else if (q) {
1223		tcf_block_offload_unbind(block, q, ei);
1224	}
1225}
1226
1227static void tcf_block_refcnt_put(struct tcf_block *block, bool rtnl_held)
1228{
1229	__tcf_block_put(block, NULL, NULL, rtnl_held);
1230}
1231
1232/* Find tcf block.
1233 * Set q, parent, cl when appropriate.
1234 */
1235
1236static struct tcf_block *tcf_block_find(struct net *net, struct Qdisc **q,
1237					u32 *parent, unsigned long *cl,
1238					int ifindex, u32 block_index,
1239					struct netlink_ext_ack *extack)
1240{
1241	struct tcf_block *block;
1242	int err = 0;
1243
1244	ASSERT_RTNL();
1245
1246	err = __tcf_qdisc_find(net, q, parent, ifindex, true, extack);
1247	if (err)
1248		goto errout;
1249
1250	err = __tcf_qdisc_cl_find(*q, *parent, cl, ifindex, extack);
1251	if (err)
1252		goto errout_qdisc;
1253
1254	block = __tcf_block_find(net, *q, *cl, ifindex, block_index, extack);
1255	if (IS_ERR(block)) {
1256		err = PTR_ERR(block);
1257		goto errout_qdisc;
1258	}
1259
1260	return block;
1261
1262errout_qdisc:
1263	if (*q)
1264		qdisc_put(*q);
1265errout:
1266	*q = NULL;
1267	return ERR_PTR(err);
1268}
1269
1270static void tcf_block_release(struct Qdisc *q, struct tcf_block *block,
1271			      bool rtnl_held)
1272{
1273	if (!IS_ERR_OR_NULL(block))
1274		tcf_block_refcnt_put(block, rtnl_held);
1275
1276	if (q) {
1277		if (rtnl_held)
1278			qdisc_put(q);
1279		else
1280			qdisc_put_unlocked(q);
1281	}
1282}
1283
1284struct tcf_block_owner_item {
1285	struct list_head list;
1286	struct Qdisc *q;
1287	enum flow_block_binder_type binder_type;
1288};
1289
1290static void
1291tcf_block_owner_netif_keep_dst(struct tcf_block *block,
1292			       struct Qdisc *q,
1293			       enum flow_block_binder_type binder_type)
1294{
1295	if (block->keep_dst &&
1296	    binder_type != FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS &&
1297	    binder_type != FLOW_BLOCK_BINDER_TYPE_CLSACT_EGRESS)
1298		netif_keep_dst(qdisc_dev(q));
1299}
1300
1301void tcf_block_netif_keep_dst(struct tcf_block *block)
1302{
1303	struct tcf_block_owner_item *item;
1304
1305	block->keep_dst = true;
1306	list_for_each_entry(item, &block->owner_list, list)
1307		tcf_block_owner_netif_keep_dst(block, item->q,
1308					       item->binder_type);
1309}
1310EXPORT_SYMBOL(tcf_block_netif_keep_dst);
1311
1312static int tcf_block_owner_add(struct tcf_block *block,
1313			       struct Qdisc *q,
1314			       enum flow_block_binder_type binder_type)
1315{
1316	struct tcf_block_owner_item *item;
1317
1318	item = kmalloc(sizeof(*item), GFP_KERNEL);
1319	if (!item)
1320		return -ENOMEM;
1321	item->q = q;
1322	item->binder_type = binder_type;
1323	list_add(&item->list, &block->owner_list);
1324	return 0;
1325}
1326
1327static void tcf_block_owner_del(struct tcf_block *block,
1328				struct Qdisc *q,
1329				enum flow_block_binder_type binder_type)
1330{
1331	struct tcf_block_owner_item *item;
1332
1333	list_for_each_entry(item, &block->owner_list, list) {
1334		if (item->q == q && item->binder_type == binder_type) {
1335			list_del(&item->list);
1336			kfree(item);
1337			return;
1338		}
1339	}
1340	WARN_ON(1);
1341}
1342
 
 
 
 
 
 
 
 
1343int tcf_block_get_ext(struct tcf_block **p_block, struct Qdisc *q,
1344		      struct tcf_block_ext_info *ei,
1345		      struct netlink_ext_ack *extack)
1346{
 
1347	struct net *net = qdisc_net(q);
1348	struct tcf_block *block = NULL;
1349	int err;
1350
1351	if (ei->block_index)
1352		/* block_index not 0 means the shared block is requested */
1353		block = tcf_block_refcnt_get(net, ei->block_index);
1354
1355	if (!block) {
1356		block = tcf_block_create(net, q, ei->block_index, extack);
1357		if (IS_ERR(block))
1358			return PTR_ERR(block);
1359		if (tcf_block_shared(block)) {
1360			err = tcf_block_insert(block, net, extack);
1361			if (err)
1362				goto err_block_insert;
1363		}
1364	}
1365
1366	err = tcf_block_owner_add(block, q, ei->binder_type);
1367	if (err)
1368		goto err_block_owner_add;
1369
1370	tcf_block_owner_netif_keep_dst(block, q, ei->binder_type);
1371
1372	err = tcf_chain0_head_change_cb_add(block, ei, extack);
1373	if (err)
1374		goto err_chain0_head_change_cb_add;
1375
1376	err = tcf_block_offload_bind(block, q, ei, extack);
1377	if (err)
1378		goto err_block_offload_bind;
1379
 
 
 
 
 
 
 
 
1380	*p_block = block;
1381	return 0;
1382
 
1383err_block_offload_bind:
1384	tcf_chain0_head_change_cb_del(block, ei);
1385err_chain0_head_change_cb_add:
1386	tcf_block_owner_del(block, q, ei->binder_type);
1387err_block_owner_add:
1388err_block_insert:
1389	tcf_block_refcnt_put(block, true);
1390	return err;
1391}
1392EXPORT_SYMBOL(tcf_block_get_ext);
1393
1394static void tcf_chain_head_change_dflt(struct tcf_proto *tp_head, void *priv)
1395{
1396	struct tcf_proto __rcu **p_filter_chain = priv;
1397
1398	rcu_assign_pointer(*p_filter_chain, tp_head);
1399}
1400
1401int tcf_block_get(struct tcf_block **p_block,
1402		  struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q,
1403		  struct netlink_ext_ack *extack)
1404{
1405	struct tcf_block_ext_info ei = {
1406		.chain_head_change = tcf_chain_head_change_dflt,
1407		.chain_head_change_priv = p_filter_chain,
1408	};
1409
1410	WARN_ON(!p_filter_chain);
1411	return tcf_block_get_ext(p_block, q, &ei, extack);
1412}
1413EXPORT_SYMBOL(tcf_block_get);
1414
1415/* XXX: Standalone actions are not allowed to jump to any chain, and bound
1416 * actions should be all removed after flushing.
1417 */
1418void tcf_block_put_ext(struct tcf_block *block, struct Qdisc *q,
1419		       struct tcf_block_ext_info *ei)
1420{
 
 
1421	if (!block)
1422		return;
 
 
1423	tcf_chain0_head_change_cb_del(block, ei);
1424	tcf_block_owner_del(block, q, ei->binder_type);
1425
1426	__tcf_block_put(block, q, ei, true);
1427}
1428EXPORT_SYMBOL(tcf_block_put_ext);
1429
1430void tcf_block_put(struct tcf_block *block)
1431{
1432	struct tcf_block_ext_info ei = {0, };
1433
1434	if (!block)
1435		return;
1436	tcf_block_put_ext(block, block->q, &ei);
1437}
1438
1439EXPORT_SYMBOL(tcf_block_put);
1440
1441static int
1442tcf_block_playback_offloads(struct tcf_block *block, flow_setup_cb_t *cb,
1443			    void *cb_priv, bool add, bool offload_in_use,
1444			    struct netlink_ext_ack *extack)
1445{
1446	struct tcf_chain *chain, *chain_prev;
1447	struct tcf_proto *tp, *tp_prev;
1448	int err;
1449
1450	lockdep_assert_held(&block->cb_lock);
1451
1452	for (chain = __tcf_get_next_chain(block, NULL);
1453	     chain;
1454	     chain_prev = chain,
1455		     chain = __tcf_get_next_chain(block, chain),
1456		     tcf_chain_put(chain_prev)) {
 
 
 
1457		for (tp = __tcf_get_next_proto(chain, NULL); tp;
1458		     tp_prev = tp,
1459			     tp = __tcf_get_next_proto(chain, tp),
1460			     tcf_proto_put(tp_prev, true, NULL)) {
1461			if (tp->ops->reoffload) {
1462				err = tp->ops->reoffload(tp, add, cb, cb_priv,
1463							 extack);
1464				if (err && add)
1465					goto err_playback_remove;
1466			} else if (add && offload_in_use) {
1467				err = -EOPNOTSUPP;
1468				NL_SET_ERR_MSG(extack, "Filter HW offload failed - classifier without re-offloading support");
1469				goto err_playback_remove;
1470			}
1471		}
 
 
 
1472	}
1473
1474	return 0;
1475
1476err_playback_remove:
1477	tcf_proto_put(tp, true, NULL);
1478	tcf_chain_put(chain);
1479	tcf_block_playback_offloads(block, cb, cb_priv, false, offload_in_use,
1480				    extack);
1481	return err;
1482}
1483
1484static int tcf_block_bind(struct tcf_block *block,
1485			  struct flow_block_offload *bo)
1486{
1487	struct flow_block_cb *block_cb, *next;
1488	int err, i = 0;
1489
1490	lockdep_assert_held(&block->cb_lock);
1491
1492	list_for_each_entry(block_cb, &bo->cb_list, list) {
1493		err = tcf_block_playback_offloads(block, block_cb->cb,
1494						  block_cb->cb_priv, true,
1495						  tcf_block_offload_in_use(block),
1496						  bo->extack);
1497		if (err)
1498			goto err_unroll;
1499		if (!bo->unlocked_driver_cb)
1500			block->lockeddevcnt++;
1501
1502		i++;
1503	}
1504	list_splice(&bo->cb_list, &block->flow_block.cb_list);
1505
1506	return 0;
1507
1508err_unroll:
1509	list_for_each_entry_safe(block_cb, next, &bo->cb_list, list) {
 
1510		if (i-- > 0) {
1511			list_del(&block_cb->list);
1512			tcf_block_playback_offloads(block, block_cb->cb,
1513						    block_cb->cb_priv, false,
1514						    tcf_block_offload_in_use(block),
1515						    NULL);
1516			if (!bo->unlocked_driver_cb)
1517				block->lockeddevcnt--;
1518		}
1519		flow_block_cb_free(block_cb);
1520	}
1521
1522	return err;
1523}
1524
1525static void tcf_block_unbind(struct tcf_block *block,
1526			     struct flow_block_offload *bo)
1527{
1528	struct flow_block_cb *block_cb, *next;
1529
1530	lockdep_assert_held(&block->cb_lock);
1531
1532	list_for_each_entry_safe(block_cb, next, &bo->cb_list, list) {
1533		tcf_block_playback_offloads(block, block_cb->cb,
1534					    block_cb->cb_priv, false,
1535					    tcf_block_offload_in_use(block),
1536					    NULL);
1537		list_del(&block_cb->list);
1538		flow_block_cb_free(block_cb);
1539		if (!bo->unlocked_driver_cb)
1540			block->lockeddevcnt--;
1541	}
1542}
1543
1544static int tcf_block_setup(struct tcf_block *block,
1545			   struct flow_block_offload *bo)
1546{
1547	int err;
1548
1549	switch (bo->command) {
1550	case FLOW_BLOCK_BIND:
1551		err = tcf_block_bind(block, bo);
1552		break;
1553	case FLOW_BLOCK_UNBIND:
1554		err = 0;
1555		tcf_block_unbind(block, bo);
1556		break;
1557	default:
1558		WARN_ON_ONCE(1);
1559		err = -EOPNOTSUPP;
1560	}
1561
1562	return err;
1563}
1564
1565/* Main classifier routine: scans classifier chain attached
1566 * to this qdisc, (optionally) tests for protocol and asks
1567 * specific classifiers.
1568 */
1569int tcf_classify(struct sk_buff *skb, const struct tcf_proto *tp,
1570		 struct tcf_result *res, bool compat_mode)
 
 
 
 
 
 
1571{
1572#ifdef CONFIG_NET_CLS_ACT
1573	const int max_reclassify_loop = 4;
1574	const struct tcf_proto *orig_tp = tp;
1575	const struct tcf_proto *first_tp;
1576	int limit = 0;
1577
1578reclassify:
1579#endif
1580	for (; tp; tp = rcu_dereference_bh(tp->next)) {
1581		__be16 protocol = tc_skb_protocol(skb);
1582		int err;
1583
1584		if (tp->protocol != protocol &&
1585		    tp->protocol != htons(ETH_P_ALL))
1586			continue;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1587
1588		err = tp->classify(skb, tp, res);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1589#ifdef CONFIG_NET_CLS_ACT
1590		if (unlikely(err == TC_ACT_RECLASSIFY && !compat_mode)) {
1591			first_tp = orig_tp;
 
1592			goto reset;
1593		} else if (unlikely(TC_ACT_EXT_CMP(err, TC_ACT_GOTO_CHAIN))) {
1594			first_tp = res->goto_tp;
1595
1596#if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
1597			{
1598				struct tc_skb_ext *ext;
1599
1600				ext = skb_ext_add(skb, TC_SKB_EXT);
1601				if (WARN_ON_ONCE(!ext))
1602					return TC_ACT_SHOT;
1603
1604				ext->chain = err & TC_ACT_EXT_VAL_MASK;
1605			}
1606#endif
1607			goto reset;
1608		}
1609#endif
1610		if (err >= 0)
1611			return err;
1612	}
1613
 
 
 
 
 
 
1614	return TC_ACT_UNSPEC; /* signal: continue lookup */
1615#ifdef CONFIG_NET_CLS_ACT
1616reset:
1617	if (unlikely(limit++ >= max_reclassify_loop)) {
1618		net_notice_ratelimited("%u: reclassify loop, rule prio %u, protocol %02x\n",
1619				       tp->chain->block->index,
1620				       tp->prio & 0xffff,
1621				       ntohs(tp->protocol));
 
 
1622		return TC_ACT_SHOT;
1623	}
1624
1625	tp = first_tp;
1626	goto reclassify;
1627#endif
1628}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1629EXPORT_SYMBOL(tcf_classify);
1630
1631struct tcf_chain_info {
1632	struct tcf_proto __rcu **pprev;
1633	struct tcf_proto __rcu *next;
1634};
1635
1636static struct tcf_proto *tcf_chain_tp_prev(struct tcf_chain *chain,
1637					   struct tcf_chain_info *chain_info)
1638{
1639	return tcf_chain_dereference(*chain_info->pprev, chain);
1640}
1641
1642static int tcf_chain_tp_insert(struct tcf_chain *chain,
1643			       struct tcf_chain_info *chain_info,
1644			       struct tcf_proto *tp)
1645{
1646	if (chain->flushing)
1647		return -EAGAIN;
1648
 
1649	if (*chain_info->pprev == chain->filter_chain)
1650		tcf_chain0_head_change(chain, tp);
1651	tcf_proto_get(tp);
1652	RCU_INIT_POINTER(tp->next, tcf_chain_tp_prev(chain, chain_info));
1653	rcu_assign_pointer(*chain_info->pprev, tp);
1654
1655	return 0;
1656}
1657
1658static void tcf_chain_tp_remove(struct tcf_chain *chain,
1659				struct tcf_chain_info *chain_info,
1660				struct tcf_proto *tp)
1661{
1662	struct tcf_proto *next = tcf_chain_dereference(chain_info->next, chain);
1663
1664	tcf_proto_mark_delete(tp);
1665	if (tp == chain->filter_chain)
1666		tcf_chain0_head_change(chain, next);
1667	RCU_INIT_POINTER(*chain_info->pprev, next);
1668}
1669
1670static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain,
1671					   struct tcf_chain_info *chain_info,
1672					   u32 protocol, u32 prio,
1673					   bool prio_allocate);
1674
1675/* Try to insert new proto.
1676 * If proto with specified priority already exists, free new proto
1677 * and return existing one.
1678 */
1679
1680static struct tcf_proto *tcf_chain_tp_insert_unique(struct tcf_chain *chain,
1681						    struct tcf_proto *tp_new,
1682						    u32 protocol, u32 prio,
1683						    bool rtnl_held)
1684{
1685	struct tcf_chain_info chain_info;
1686	struct tcf_proto *tp;
1687	int err = 0;
1688
1689	mutex_lock(&chain->filter_chain_lock);
1690
1691	if (tcf_proto_exists_destroying(chain, tp_new)) {
1692		mutex_unlock(&chain->filter_chain_lock);
1693		tcf_proto_destroy(tp_new, rtnl_held, false, NULL);
1694		return ERR_PTR(-EAGAIN);
1695	}
1696
1697	tp = tcf_chain_tp_find(chain, &chain_info,
1698			       protocol, prio, false);
1699	if (!tp)
1700		err = tcf_chain_tp_insert(chain, &chain_info, tp_new);
1701	mutex_unlock(&chain->filter_chain_lock);
1702
1703	if (tp) {
1704		tcf_proto_destroy(tp_new, rtnl_held, false, NULL);
1705		tp_new = tp;
1706	} else if (err) {
1707		tcf_proto_destroy(tp_new, rtnl_held, false, NULL);
1708		tp_new = ERR_PTR(err);
1709	}
1710
1711	return tp_new;
1712}
1713
1714static void tcf_chain_tp_delete_empty(struct tcf_chain *chain,
1715				      struct tcf_proto *tp, bool rtnl_held,
1716				      struct netlink_ext_ack *extack)
1717{
1718	struct tcf_chain_info chain_info;
1719	struct tcf_proto *tp_iter;
1720	struct tcf_proto **pprev;
1721	struct tcf_proto *next;
1722
1723	mutex_lock(&chain->filter_chain_lock);
1724
1725	/* Atomically find and remove tp from chain. */
1726	for (pprev = &chain->filter_chain;
1727	     (tp_iter = tcf_chain_dereference(*pprev, chain));
1728	     pprev = &tp_iter->next) {
1729		if (tp_iter == tp) {
1730			chain_info.pprev = pprev;
1731			chain_info.next = tp_iter->next;
1732			WARN_ON(tp_iter->deleting);
1733			break;
1734		}
1735	}
1736	/* Verify that tp still exists and no new filters were inserted
1737	 * concurrently.
1738	 * Mark tp for deletion if it is empty.
1739	 */
1740	if (!tp_iter || !tcf_proto_check_delete(tp, rtnl_held)) {
1741		mutex_unlock(&chain->filter_chain_lock);
1742		return;
1743	}
1744
1745	tcf_proto_signal_destroying(chain, tp);
1746	next = tcf_chain_dereference(chain_info.next, chain);
1747	if (tp == chain->filter_chain)
1748		tcf_chain0_head_change(chain, next);
1749	RCU_INIT_POINTER(*chain_info.pprev, next);
1750	mutex_unlock(&chain->filter_chain_lock);
1751
1752	tcf_proto_put(tp, rtnl_held, extack);
1753}
1754
1755static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain,
1756					   struct tcf_chain_info *chain_info,
1757					   u32 protocol, u32 prio,
1758					   bool prio_allocate)
1759{
1760	struct tcf_proto **pprev;
1761	struct tcf_proto *tp;
1762
1763	/* Check the chain for existence of proto-tcf with this priority */
1764	for (pprev = &chain->filter_chain;
1765	     (tp = tcf_chain_dereference(*pprev, chain));
1766	     pprev = &tp->next) {
1767		if (tp->prio >= prio) {
1768			if (tp->prio == prio) {
1769				if (prio_allocate ||
1770				    (tp->protocol != protocol && protocol))
1771					return ERR_PTR(-EINVAL);
1772			} else {
1773				tp = NULL;
1774			}
1775			break;
1776		}
1777	}
1778	chain_info->pprev = pprev;
1779	if (tp) {
1780		chain_info->next = tp->next;
1781		tcf_proto_get(tp);
1782	} else {
1783		chain_info->next = NULL;
1784	}
1785	return tp;
1786}
1787
1788static int tcf_fill_node(struct net *net, struct sk_buff *skb,
1789			 struct tcf_proto *tp, struct tcf_block *block,
1790			 struct Qdisc *q, u32 parent, void *fh,
1791			 u32 portid, u32 seq, u16 flags, int event,
1792			 bool rtnl_held)
 
1793{
1794	struct tcmsg *tcm;
1795	struct nlmsghdr  *nlh;
1796	unsigned char *b = skb_tail_pointer(skb);
1797
1798	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
1799	if (!nlh)
1800		goto out_nlmsg_trim;
1801	tcm = nlmsg_data(nlh);
1802	tcm->tcm_family = AF_UNSPEC;
1803	tcm->tcm__pad1 = 0;
1804	tcm->tcm__pad2 = 0;
1805	if (q) {
1806		tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
1807		tcm->tcm_parent = parent;
1808	} else {
1809		tcm->tcm_ifindex = TCM_IFINDEX_MAGIC_BLOCK;
1810		tcm->tcm_block_index = block->index;
1811	}
1812	tcm->tcm_info = TC_H_MAKE(tp->prio, tp->protocol);
1813	if (nla_put_string(skb, TCA_KIND, tp->ops->kind))
1814		goto nla_put_failure;
1815	if (nla_put_u32(skb, TCA_CHAIN, tp->chain->index))
1816		goto nla_put_failure;
1817	if (!fh) {
1818		tcm->tcm_handle = 0;
 
 
 
 
 
 
 
 
1819	} else {
1820		if (tp->ops->dump &&
1821		    tp->ops->dump(net, tp, fh, skb, tcm, rtnl_held) < 0)
1822			goto nla_put_failure;
1823	}
 
 
 
 
 
1824	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 
1825	return skb->len;
1826
1827out_nlmsg_trim:
1828nla_put_failure:
 
1829	nlmsg_trim(skb, b);
1830	return -1;
1831}
1832
1833static int tfilter_notify(struct net *net, struct sk_buff *oskb,
1834			  struct nlmsghdr *n, struct tcf_proto *tp,
1835			  struct tcf_block *block, struct Qdisc *q,
1836			  u32 parent, void *fh, int event, bool unicast,
1837			  bool rtnl_held)
1838{
1839	struct sk_buff *skb;
1840	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
1841	int err = 0;
1842
 
 
 
1843	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1844	if (!skb)
1845		return -ENOBUFS;
1846
1847	if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid,
1848			  n->nlmsg_seq, n->nlmsg_flags, event,
1849			  rtnl_held) <= 0) {
1850		kfree_skb(skb);
1851		return -EINVAL;
1852	}
1853
1854	if (unicast)
1855		err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
1856	else
1857		err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1858				     n->nlmsg_flags & NLM_F_ECHO);
1859
1860	if (err > 0)
1861		err = 0;
1862	return err;
1863}
1864
1865static int tfilter_del_notify(struct net *net, struct sk_buff *oskb,
1866			      struct nlmsghdr *n, struct tcf_proto *tp,
1867			      struct tcf_block *block, struct Qdisc *q,
1868			      u32 parent, void *fh, bool unicast, bool *last,
1869			      bool rtnl_held, struct netlink_ext_ack *extack)
1870{
1871	struct sk_buff *skb;
1872	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
1873	int err;
1874
 
 
 
1875	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1876	if (!skb)
1877		return -ENOBUFS;
1878
1879	if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid,
1880			  n->nlmsg_seq, n->nlmsg_flags, RTM_DELTFILTER,
1881			  rtnl_held) <= 0) {
1882		NL_SET_ERR_MSG(extack, "Failed to build del event notification");
1883		kfree_skb(skb);
1884		return -EINVAL;
1885	}
1886
1887	err = tp->ops->delete(tp, fh, last, rtnl_held, extack);
1888	if (err) {
1889		kfree_skb(skb);
1890		return err;
1891	}
1892
1893	if (unicast)
1894		err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
1895	else
1896		err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1897				     n->nlmsg_flags & NLM_F_ECHO);
1898	if (err < 0)
1899		NL_SET_ERR_MSG(extack, "Failed to send filter delete notification");
1900
1901	if (err > 0)
1902		err = 0;
1903	return err;
1904}
1905
1906static void tfilter_notify_chain(struct net *net, struct sk_buff *oskb,
1907				 struct tcf_block *block, struct Qdisc *q,
1908				 u32 parent, struct nlmsghdr *n,
1909				 struct tcf_chain *chain, int event,
1910				 bool rtnl_held)
1911{
1912	struct tcf_proto *tp;
1913
1914	for (tp = tcf_get_next_proto(chain, NULL, rtnl_held);
1915	     tp; tp = tcf_get_next_proto(chain, tp, rtnl_held))
1916		tfilter_notify(net, oskb, n, tp, block,
1917			       q, parent, NULL, event, false, rtnl_held);
1918}
1919
1920static void tfilter_put(struct tcf_proto *tp, void *fh)
1921{
1922	if (tp->ops->put && fh)
1923		tp->ops->put(tp, fh);
1924}
1925
 
 
 
 
 
1926static int tc_new_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
1927			  struct netlink_ext_ack *extack)
1928{
1929	struct net *net = sock_net(skb->sk);
1930	struct nlattr *tca[TCA_MAX + 1];
1931	char name[IFNAMSIZ];
1932	struct tcmsg *t;
1933	u32 protocol;
1934	u32 prio;
1935	bool prio_allocate;
1936	u32 parent;
1937	u32 chain_index;
1938	struct Qdisc *q = NULL;
1939	struct tcf_chain_info chain_info;
1940	struct tcf_chain *chain = NULL;
1941	struct tcf_block *block;
1942	struct tcf_proto *tp;
1943	unsigned long cl;
1944	void *fh;
1945	int err;
1946	int tp_created;
1947	bool rtnl_held = false;
1948
1949	if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
1950		return -EPERM;
1951
1952replay:
1953	tp_created = 0;
1954
1955	err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
1956				     rtm_tca_policy, extack);
1957	if (err < 0)
1958		return err;
1959
1960	t = nlmsg_data(n);
1961	protocol = TC_H_MIN(t->tcm_info);
1962	prio = TC_H_MAJ(t->tcm_info);
1963	prio_allocate = false;
1964	parent = t->tcm_parent;
1965	tp = NULL;
1966	cl = 0;
1967	block = NULL;
 
 
 
1968
1969	if (prio == 0) {
1970		/* If no priority is provided by the user,
1971		 * we allocate one.
1972		 */
1973		if (n->nlmsg_flags & NLM_F_CREATE) {
1974			prio = TC_H_MAKE(0x80000000U, 0U);
1975			prio_allocate = true;
1976		} else {
1977			NL_SET_ERR_MSG(extack, "Invalid filter command with priority of zero");
1978			return -ENOENT;
1979		}
1980	}
1981
1982	/* Find head of filter chain. */
1983
1984	err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack);
1985	if (err)
1986		return err;
1987
1988	if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
1989		NL_SET_ERR_MSG(extack, "Specified TC filter name too long");
1990		err = -EINVAL;
1991		goto errout;
1992	}
1993
1994	/* Take rtnl mutex if rtnl_held was set to true on previous iteration,
1995	 * block is shared (no qdisc found), qdisc is not unlocked, classifier
1996	 * type is not specified, classifier is not unlocked.
1997	 */
1998	if (rtnl_held ||
1999	    (q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
2000	    !tcf_proto_is_unlocked(name)) {
2001		rtnl_held = true;
2002		rtnl_lock();
2003	}
2004
2005	err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack);
2006	if (err)
2007		goto errout;
2008
2009	block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index,
2010				 extack);
2011	if (IS_ERR(block)) {
2012		err = PTR_ERR(block);
2013		goto errout;
2014	}
 
2015
2016	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2017	if (chain_index > TC_ACT_EXT_VAL_MASK) {
2018		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2019		err = -EINVAL;
2020		goto errout;
2021	}
2022	chain = tcf_chain_get(block, chain_index, true);
2023	if (!chain) {
2024		NL_SET_ERR_MSG(extack, "Cannot create specified filter chain");
2025		err = -ENOMEM;
2026		goto errout;
2027	}
2028
2029	mutex_lock(&chain->filter_chain_lock);
2030	tp = tcf_chain_tp_find(chain, &chain_info, protocol,
2031			       prio, prio_allocate);
2032	if (IS_ERR(tp)) {
2033		NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
2034		err = PTR_ERR(tp);
2035		goto errout_locked;
2036	}
2037
2038	if (tp == NULL) {
2039		struct tcf_proto *tp_new = NULL;
2040
2041		if (chain->flushing) {
2042			err = -EAGAIN;
2043			goto errout_locked;
2044		}
2045
2046		/* Proto-tcf does not exist, create new one */
2047
2048		if (tca[TCA_KIND] == NULL || !protocol) {
2049			NL_SET_ERR_MSG(extack, "Filter kind and protocol must be specified");
2050			err = -EINVAL;
2051			goto errout_locked;
2052		}
2053
2054		if (!(n->nlmsg_flags & NLM_F_CREATE)) {
2055			NL_SET_ERR_MSG(extack, "Need both RTM_NEWTFILTER and NLM_F_CREATE to create a new filter");
2056			err = -ENOENT;
2057			goto errout_locked;
2058		}
2059
2060		if (prio_allocate)
2061			prio = tcf_auto_prio(tcf_chain_tp_prev(chain,
2062							       &chain_info));
2063
2064		mutex_unlock(&chain->filter_chain_lock);
2065		tp_new = tcf_proto_create(nla_data(tca[TCA_KIND]),
2066					  protocol, prio, chain, rtnl_held,
2067					  extack);
2068		if (IS_ERR(tp_new)) {
2069			err = PTR_ERR(tp_new);
2070			goto errout_tp;
2071		}
2072
2073		tp_created = 1;
2074		tp = tcf_chain_tp_insert_unique(chain, tp_new, protocol, prio,
2075						rtnl_held);
2076		if (IS_ERR(tp)) {
2077			err = PTR_ERR(tp);
2078			goto errout_tp;
2079		}
2080	} else {
2081		mutex_unlock(&chain->filter_chain_lock);
2082	}
2083
2084	if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
2085		NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
2086		err = -EINVAL;
2087		goto errout;
2088	}
2089
2090	fh = tp->ops->get(tp, t->tcm_handle);
2091
2092	if (!fh) {
2093		if (!(n->nlmsg_flags & NLM_F_CREATE)) {
2094			NL_SET_ERR_MSG(extack, "Need both RTM_NEWTFILTER and NLM_F_CREATE to create a new filter");
2095			err = -ENOENT;
2096			goto errout;
2097		}
2098	} else if (n->nlmsg_flags & NLM_F_EXCL) {
2099		tfilter_put(tp, fh);
2100		NL_SET_ERR_MSG(extack, "Filter already exists");
2101		err = -EEXIST;
2102		goto errout;
2103	}
2104
2105	if (chain->tmplt_ops && chain->tmplt_ops != tp->ops) {
 
2106		NL_SET_ERR_MSG(extack, "Chain template is set to a different filter kind");
2107		err = -EINVAL;
2108		goto errout;
2109	}
2110
 
 
 
 
 
 
2111	err = tp->ops->change(net, skb, tp, cl, t->tcm_handle, tca, &fh,
2112			      n->nlmsg_flags & NLM_F_CREATE ? TCA_ACT_NOREPLACE : TCA_ACT_REPLACE,
2113			      rtnl_held, extack);
2114	if (err == 0) {
2115		tfilter_notify(net, skb, n, tp, block, q, parent, fh,
2116			       RTM_NEWTFILTER, false, rtnl_held);
2117		tfilter_put(tp, fh);
2118		/* q pointer is NULL for shared blocks */
2119		if (q)
2120			q->flags &= ~TCQ_F_CAN_BYPASS;
2121	}
2122
2123errout:
2124	if (err && tp_created)
2125		tcf_chain_tp_delete_empty(chain, tp, rtnl_held, NULL);
2126errout_tp:
2127	if (chain) {
2128		if (tp && !IS_ERR(tp))
2129			tcf_proto_put(tp, rtnl_held, NULL);
2130		if (!tp_created)
2131			tcf_chain_put(chain);
2132	}
2133	tcf_block_release(q, block, rtnl_held);
2134
2135	if (rtnl_held)
2136		rtnl_unlock();
2137
2138	if (err == -EAGAIN) {
2139		/* Take rtnl lock in case EAGAIN is caused by concurrent flush
2140		 * of target chain.
2141		 */
2142		rtnl_held = true;
2143		/* Replay the request. */
2144		goto replay;
2145	}
2146	return err;
2147
2148errout_locked:
2149	mutex_unlock(&chain->filter_chain_lock);
2150	goto errout;
2151}
2152
2153static int tc_del_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
2154			  struct netlink_ext_ack *extack)
2155{
2156	struct net *net = sock_net(skb->sk);
2157	struct nlattr *tca[TCA_MAX + 1];
2158	char name[IFNAMSIZ];
2159	struct tcmsg *t;
2160	u32 protocol;
2161	u32 prio;
2162	u32 parent;
2163	u32 chain_index;
2164	struct Qdisc *q = NULL;
2165	struct tcf_chain_info chain_info;
2166	struct tcf_chain *chain = NULL;
2167	struct tcf_block *block = NULL;
2168	struct tcf_proto *tp = NULL;
2169	unsigned long cl = 0;
2170	void *fh = NULL;
2171	int err;
2172	bool rtnl_held = false;
2173
2174	if (!netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
2175		return -EPERM;
2176
2177	err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
2178				     rtm_tca_policy, extack);
2179	if (err < 0)
2180		return err;
2181
2182	t = nlmsg_data(n);
2183	protocol = TC_H_MIN(t->tcm_info);
2184	prio = TC_H_MAJ(t->tcm_info);
2185	parent = t->tcm_parent;
2186
2187	if (prio == 0 && (protocol || t->tcm_handle || tca[TCA_KIND])) {
2188		NL_SET_ERR_MSG(extack, "Cannot flush filters with protocol, handle or kind set");
2189		return -ENOENT;
2190	}
2191
2192	/* Find head of filter chain. */
2193
2194	err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack);
2195	if (err)
2196		return err;
2197
2198	if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
2199		NL_SET_ERR_MSG(extack, "Specified TC filter name too long");
2200		err = -EINVAL;
2201		goto errout;
2202	}
2203	/* Take rtnl mutex if flushing whole chain, block is shared (no qdisc
2204	 * found), qdisc is not unlocked, classifier type is not specified,
2205	 * classifier is not unlocked.
2206	 */
2207	if (!prio ||
2208	    (q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
2209	    !tcf_proto_is_unlocked(name)) {
2210		rtnl_held = true;
2211		rtnl_lock();
2212	}
2213
2214	err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack);
2215	if (err)
2216		goto errout;
2217
2218	block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index,
2219				 extack);
2220	if (IS_ERR(block)) {
2221		err = PTR_ERR(block);
2222		goto errout;
2223	}
2224
2225	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2226	if (chain_index > TC_ACT_EXT_VAL_MASK) {
2227		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2228		err = -EINVAL;
2229		goto errout;
2230	}
2231	chain = tcf_chain_get(block, chain_index, false);
2232	if (!chain) {
2233		/* User requested flush on non-existent chain. Nothing to do,
2234		 * so just return success.
2235		 */
2236		if (prio == 0) {
2237			err = 0;
2238			goto errout;
2239		}
2240		NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
2241		err = -ENOENT;
2242		goto errout;
2243	}
2244
2245	if (prio == 0) {
2246		tfilter_notify_chain(net, skb, block, q, parent, n,
2247				     chain, RTM_DELTFILTER, rtnl_held);
2248		tcf_chain_flush(chain, rtnl_held);
2249		err = 0;
2250		goto errout;
2251	}
2252
2253	mutex_lock(&chain->filter_chain_lock);
2254	tp = tcf_chain_tp_find(chain, &chain_info, protocol,
2255			       prio, false);
2256	if (!tp || IS_ERR(tp)) {
2257		NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
2258		err = tp ? PTR_ERR(tp) : -ENOENT;
2259		goto errout_locked;
2260	} else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
2261		NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
2262		err = -EINVAL;
2263		goto errout_locked;
2264	} else if (t->tcm_handle == 0) {
2265		tcf_proto_signal_destroying(chain, tp);
2266		tcf_chain_tp_remove(chain, &chain_info, tp);
2267		mutex_unlock(&chain->filter_chain_lock);
2268
2269		tcf_proto_put(tp, rtnl_held, NULL);
2270		tfilter_notify(net, skb, n, tp, block, q, parent, fh,
2271			       RTM_DELTFILTER, false, rtnl_held);
2272		err = 0;
2273		goto errout;
2274	}
2275	mutex_unlock(&chain->filter_chain_lock);
2276
2277	fh = tp->ops->get(tp, t->tcm_handle);
2278
2279	if (!fh) {
2280		NL_SET_ERR_MSG(extack, "Specified filter handle not found");
2281		err = -ENOENT;
2282	} else {
2283		bool last;
2284
2285		err = tfilter_del_notify(net, skb, n, tp, block,
2286					 q, parent, fh, false, &last,
2287					 rtnl_held, extack);
2288
2289		if (err)
2290			goto errout;
2291		if (last)
2292			tcf_chain_tp_delete_empty(chain, tp, rtnl_held, extack);
2293	}
2294
2295errout:
2296	if (chain) {
2297		if (tp && !IS_ERR(tp))
2298			tcf_proto_put(tp, rtnl_held, NULL);
2299		tcf_chain_put(chain);
2300	}
2301	tcf_block_release(q, block, rtnl_held);
2302
2303	if (rtnl_held)
2304		rtnl_unlock();
2305
2306	return err;
2307
2308errout_locked:
2309	mutex_unlock(&chain->filter_chain_lock);
2310	goto errout;
2311}
2312
2313static int tc_get_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
2314			  struct netlink_ext_ack *extack)
2315{
2316	struct net *net = sock_net(skb->sk);
2317	struct nlattr *tca[TCA_MAX + 1];
2318	char name[IFNAMSIZ];
2319	struct tcmsg *t;
2320	u32 protocol;
2321	u32 prio;
2322	u32 parent;
2323	u32 chain_index;
2324	struct Qdisc *q = NULL;
2325	struct tcf_chain_info chain_info;
2326	struct tcf_chain *chain = NULL;
2327	struct tcf_block *block = NULL;
2328	struct tcf_proto *tp = NULL;
2329	unsigned long cl = 0;
2330	void *fh = NULL;
2331	int err;
2332	bool rtnl_held = false;
2333
2334	err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
2335				     rtm_tca_policy, extack);
2336	if (err < 0)
2337		return err;
2338
2339	t = nlmsg_data(n);
2340	protocol = TC_H_MIN(t->tcm_info);
2341	prio = TC_H_MAJ(t->tcm_info);
2342	parent = t->tcm_parent;
2343
2344	if (prio == 0) {
2345		NL_SET_ERR_MSG(extack, "Invalid filter command with priority of zero");
2346		return -ENOENT;
2347	}
2348
2349	/* Find head of filter chain. */
2350
2351	err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack);
2352	if (err)
2353		return err;
2354
2355	if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
2356		NL_SET_ERR_MSG(extack, "Specified TC filter name too long");
2357		err = -EINVAL;
2358		goto errout;
2359	}
2360	/* Take rtnl mutex if block is shared (no qdisc found), qdisc is not
2361	 * unlocked, classifier type is not specified, classifier is not
2362	 * unlocked.
2363	 */
2364	if ((q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
2365	    !tcf_proto_is_unlocked(name)) {
2366		rtnl_held = true;
2367		rtnl_lock();
2368	}
2369
2370	err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack);
2371	if (err)
2372		goto errout;
2373
2374	block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index,
2375				 extack);
2376	if (IS_ERR(block)) {
2377		err = PTR_ERR(block);
2378		goto errout;
2379	}
2380
2381	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2382	if (chain_index > TC_ACT_EXT_VAL_MASK) {
2383		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2384		err = -EINVAL;
2385		goto errout;
2386	}
2387	chain = tcf_chain_get(block, chain_index, false);
2388	if (!chain) {
2389		NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
2390		err = -EINVAL;
2391		goto errout;
2392	}
2393
2394	mutex_lock(&chain->filter_chain_lock);
2395	tp = tcf_chain_tp_find(chain, &chain_info, protocol,
2396			       prio, false);
2397	mutex_unlock(&chain->filter_chain_lock);
2398	if (!tp || IS_ERR(tp)) {
2399		NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
2400		err = tp ? PTR_ERR(tp) : -ENOENT;
2401		goto errout;
2402	} else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
2403		NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
2404		err = -EINVAL;
2405		goto errout;
2406	}
2407
2408	fh = tp->ops->get(tp, t->tcm_handle);
2409
2410	if (!fh) {
2411		NL_SET_ERR_MSG(extack, "Specified filter handle not found");
2412		err = -ENOENT;
2413	} else {
2414		err = tfilter_notify(net, skb, n, tp, block, q, parent,
2415				     fh, RTM_NEWTFILTER, true, rtnl_held);
2416		if (err < 0)
2417			NL_SET_ERR_MSG(extack, "Failed to send filter notify message");
2418	}
2419
2420	tfilter_put(tp, fh);
2421errout:
2422	if (chain) {
2423		if (tp && !IS_ERR(tp))
2424			tcf_proto_put(tp, rtnl_held, NULL);
2425		tcf_chain_put(chain);
2426	}
2427	tcf_block_release(q, block, rtnl_held);
2428
2429	if (rtnl_held)
2430		rtnl_unlock();
2431
2432	return err;
2433}
2434
2435struct tcf_dump_args {
2436	struct tcf_walker w;
2437	struct sk_buff *skb;
2438	struct netlink_callback *cb;
2439	struct tcf_block *block;
2440	struct Qdisc *q;
2441	u32 parent;
 
2442};
2443
2444static int tcf_node_dump(struct tcf_proto *tp, void *n, struct tcf_walker *arg)
2445{
2446	struct tcf_dump_args *a = (void *)arg;
2447	struct net *net = sock_net(a->skb->sk);
2448
2449	return tcf_fill_node(net, a->skb, tp, a->block, a->q, a->parent,
2450			     n, NETLINK_CB(a->cb->skb).portid,
2451			     a->cb->nlh->nlmsg_seq, NLM_F_MULTI,
2452			     RTM_NEWTFILTER, true);
2453}
2454
2455static bool tcf_chain_dump(struct tcf_chain *chain, struct Qdisc *q, u32 parent,
2456			   struct sk_buff *skb, struct netlink_callback *cb,
2457			   long index_start, long *p_index)
2458{
2459	struct net *net = sock_net(skb->sk);
2460	struct tcf_block *block = chain->block;
2461	struct tcmsg *tcm = nlmsg_data(cb->nlh);
2462	struct tcf_proto *tp, *tp_prev;
2463	struct tcf_dump_args arg;
2464
2465	for (tp = __tcf_get_next_proto(chain, NULL);
2466	     tp;
2467	     tp_prev = tp,
2468		     tp = __tcf_get_next_proto(chain, tp),
2469		     tcf_proto_put(tp_prev, true, NULL),
2470		     (*p_index)++) {
2471		if (*p_index < index_start)
2472			continue;
2473		if (TC_H_MAJ(tcm->tcm_info) &&
2474		    TC_H_MAJ(tcm->tcm_info) != tp->prio)
2475			continue;
2476		if (TC_H_MIN(tcm->tcm_info) &&
2477		    TC_H_MIN(tcm->tcm_info) != tp->protocol)
2478			continue;
2479		if (*p_index > index_start)
2480			memset(&cb->args[1], 0,
2481			       sizeof(cb->args) - sizeof(cb->args[0]));
2482		if (cb->args[1] == 0) {
2483			if (tcf_fill_node(net, skb, tp, block, q, parent, NULL,
2484					  NETLINK_CB(cb->skb).portid,
2485					  cb->nlh->nlmsg_seq, NLM_F_MULTI,
2486					  RTM_NEWTFILTER, true) <= 0)
2487				goto errout;
2488			cb->args[1] = 1;
2489		}
2490		if (!tp->ops->walk)
2491			continue;
2492		arg.w.fn = tcf_node_dump;
2493		arg.skb = skb;
2494		arg.cb = cb;
2495		arg.block = block;
2496		arg.q = q;
2497		arg.parent = parent;
2498		arg.w.stop = 0;
2499		arg.w.skip = cb->args[1] - 1;
2500		arg.w.count = 0;
2501		arg.w.cookie = cb->args[2];
 
2502		tp->ops->walk(tp, &arg.w, true);
2503		cb->args[2] = arg.w.cookie;
2504		cb->args[1] = arg.w.count + 1;
2505		if (arg.w.stop)
2506			goto errout;
2507	}
2508	return true;
2509
2510errout:
2511	tcf_proto_put(tp, true, NULL);
2512	return false;
2513}
2514
 
 
 
 
 
2515/* called with RTNL */
2516static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb)
2517{
2518	struct tcf_chain *chain, *chain_prev;
2519	struct net *net = sock_net(skb->sk);
2520	struct nlattr *tca[TCA_MAX + 1];
2521	struct Qdisc *q = NULL;
2522	struct tcf_block *block;
2523	struct tcmsg *tcm = nlmsg_data(cb->nlh);
 
2524	long index_start;
2525	long index;
2526	u32 parent;
2527	int err;
2528
2529	if (nlmsg_len(cb->nlh) < sizeof(*tcm))
2530		return skb->len;
2531
2532	err = nlmsg_parse_deprecated(cb->nlh, sizeof(*tcm), tca, TCA_MAX,
2533				     NULL, cb->extack);
2534	if (err)
2535		return err;
2536
 
 
 
 
 
 
 
2537	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
2538		block = tcf_block_refcnt_get(net, tcm->tcm_block_index);
2539		if (!block)
2540			goto out;
2541		/* If we work with block index, q is NULL and parent value
2542		 * will never be used in the following code. The check
2543		 * in tcf_fill_node prevents it. However, compiler does not
2544		 * see that far, so set parent to zero to silence the warning
2545		 * about parent being uninitialized.
2546		 */
2547		parent = 0;
2548	} else {
2549		const struct Qdisc_class_ops *cops;
2550		struct net_device *dev;
2551		unsigned long cl = 0;
2552
2553		dev = __dev_get_by_index(net, tcm->tcm_ifindex);
2554		if (!dev)
2555			return skb->len;
2556
2557		parent = tcm->tcm_parent;
2558		if (!parent) {
2559			q = dev->qdisc;
2560			parent = q->handle;
2561		} else {
2562			q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
2563		}
2564		if (!q)
2565			goto out;
2566		cops = q->ops->cl_ops;
2567		if (!cops)
2568			goto out;
2569		if (!cops->tcf_block)
2570			goto out;
2571		if (TC_H_MIN(tcm->tcm_parent)) {
2572			cl = cops->find(q, tcm->tcm_parent);
2573			if (cl == 0)
2574				goto out;
2575		}
2576		block = cops->tcf_block(q, cl, NULL);
2577		if (!block)
2578			goto out;
 
2579		if (tcf_block_shared(block))
2580			q = NULL;
2581	}
2582
2583	index_start = cb->args[0];
2584	index = 0;
2585
2586	for (chain = __tcf_get_next_chain(block, NULL);
2587	     chain;
2588	     chain_prev = chain,
2589		     chain = __tcf_get_next_chain(block, chain),
2590		     tcf_chain_put(chain_prev)) {
2591		if (tca[TCA_CHAIN] &&
2592		    nla_get_u32(tca[TCA_CHAIN]) != chain->index)
2593			continue;
2594		if (!tcf_chain_dump(chain, q, parent, skb, cb,
2595				    index_start, &index)) {
2596			tcf_chain_put(chain);
2597			err = -EMSGSIZE;
2598			break;
2599		}
2600	}
2601
2602	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK)
2603		tcf_block_refcnt_put(block, true);
2604	cb->args[0] = index;
2605
2606out:
2607	/* If we did no progress, the error (EMSGSIZE) is real */
2608	if (skb->len == 0 && err)
2609		return err;
2610	return skb->len;
2611}
2612
2613static int tc_chain_fill_node(const struct tcf_proto_ops *tmplt_ops,
2614			      void *tmplt_priv, u32 chain_index,
2615			      struct net *net, struct sk_buff *skb,
2616			      struct tcf_block *block,
2617			      u32 portid, u32 seq, u16 flags, int event)
 
2618{
2619	unsigned char *b = skb_tail_pointer(skb);
2620	const struct tcf_proto_ops *ops;
2621	struct nlmsghdr *nlh;
2622	struct tcmsg *tcm;
2623	void *priv;
2624
2625	ops = tmplt_ops;
2626	priv = tmplt_priv;
2627
2628	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
2629	if (!nlh)
2630		goto out_nlmsg_trim;
2631	tcm = nlmsg_data(nlh);
2632	tcm->tcm_family = AF_UNSPEC;
2633	tcm->tcm__pad1 = 0;
2634	tcm->tcm__pad2 = 0;
2635	tcm->tcm_handle = 0;
2636	if (block->q) {
2637		tcm->tcm_ifindex = qdisc_dev(block->q)->ifindex;
2638		tcm->tcm_parent = block->q->handle;
2639	} else {
2640		tcm->tcm_ifindex = TCM_IFINDEX_MAGIC_BLOCK;
2641		tcm->tcm_block_index = block->index;
2642	}
2643
2644	if (nla_put_u32(skb, TCA_CHAIN, chain_index))
2645		goto nla_put_failure;
2646
2647	if (ops) {
2648		if (nla_put_string(skb, TCA_KIND, ops->kind))
2649			goto nla_put_failure;
2650		if (ops->tmplt_dump(skb, net, priv) < 0)
2651			goto nla_put_failure;
2652	}
2653
 
 
 
 
2654	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 
2655	return skb->len;
2656
2657out_nlmsg_trim:
2658nla_put_failure:
2659	nlmsg_trim(skb, b);
2660	return -EMSGSIZE;
2661}
2662
2663static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb,
2664			   u32 seq, u16 flags, int event, bool unicast)
 
2665{
2666	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
2667	struct tcf_block *block = chain->block;
2668	struct net *net = block->net;
2669	struct sk_buff *skb;
2670	int err = 0;
2671
 
 
 
2672	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2673	if (!skb)
2674		return -ENOBUFS;
2675
2676	if (tc_chain_fill_node(chain->tmplt_ops, chain->tmplt_priv,
2677			       chain->index, net, skb, block, portid,
2678			       seq, flags, event) <= 0) {
2679		kfree_skb(skb);
2680		return -EINVAL;
2681	}
2682
2683	if (unicast)
2684		err = netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
2685	else
2686		err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
2687				     flags & NLM_F_ECHO);
2688
2689	if (err > 0)
2690		err = 0;
2691	return err;
2692}
2693
2694static int tc_chain_notify_delete(const struct tcf_proto_ops *tmplt_ops,
2695				  void *tmplt_priv, u32 chain_index,
2696				  struct tcf_block *block, struct sk_buff *oskb,
2697				  u32 seq, u16 flags, bool unicast)
2698{
2699	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
2700	struct net *net = block->net;
2701	struct sk_buff *skb;
2702
 
 
 
2703	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2704	if (!skb)
2705		return -ENOBUFS;
2706
2707	if (tc_chain_fill_node(tmplt_ops, tmplt_priv, chain_index, net, skb,
2708			       block, portid, seq, flags, RTM_DELCHAIN) <= 0) {
2709		kfree_skb(skb);
2710		return -EINVAL;
2711	}
2712
2713	if (unicast)
2714		return netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
2715
2716	return rtnetlink_send(skb, net, portid, RTNLGRP_TC, flags & NLM_F_ECHO);
2717}
2718
2719static int tc_chain_tmplt_add(struct tcf_chain *chain, struct net *net,
2720			      struct nlattr **tca,
2721			      struct netlink_ext_ack *extack)
2722{
2723	const struct tcf_proto_ops *ops;
 
2724	void *tmplt_priv;
2725
2726	/* If kind is not set, user did not specify template. */
2727	if (!tca[TCA_KIND])
2728		return 0;
2729
2730	ops = tcf_proto_lookup_ops(nla_data(tca[TCA_KIND]), true, extack);
 
 
 
 
 
2731	if (IS_ERR(ops))
2732		return PTR_ERR(ops);
2733	if (!ops->tmplt_create || !ops->tmplt_destroy || !ops->tmplt_dump) {
 
2734		NL_SET_ERR_MSG(extack, "Chain templates are not supported with specified classifier");
 
2735		return -EOPNOTSUPP;
2736	}
2737
2738	tmplt_priv = ops->tmplt_create(net, chain, tca, extack);
2739	if (IS_ERR(tmplt_priv)) {
2740		module_put(ops->owner);
2741		return PTR_ERR(tmplt_priv);
2742	}
2743	chain->tmplt_ops = ops;
2744	chain->tmplt_priv = tmplt_priv;
2745	return 0;
2746}
2747
2748static void tc_chain_tmplt_del(const struct tcf_proto_ops *tmplt_ops,
2749			       void *tmplt_priv)
2750{
2751	/* If template ops are set, no work to do for us. */
2752	if (!tmplt_ops)
2753		return;
2754
2755	tmplt_ops->tmplt_destroy(tmplt_priv);
2756	module_put(tmplt_ops->owner);
2757}
2758
2759/* Add/delete/get a chain */
2760
2761static int tc_ctl_chain(struct sk_buff *skb, struct nlmsghdr *n,
2762			struct netlink_ext_ack *extack)
2763{
2764	struct net *net = sock_net(skb->sk);
2765	struct nlattr *tca[TCA_MAX + 1];
2766	struct tcmsg *t;
2767	u32 parent;
2768	u32 chain_index;
2769	struct Qdisc *q = NULL;
2770	struct tcf_chain *chain = NULL;
2771	struct tcf_block *block;
2772	unsigned long cl;
2773	int err;
2774
2775	if (n->nlmsg_type != RTM_GETCHAIN &&
2776	    !netlink_ns_capable(skb, net->user_ns, CAP_NET_ADMIN))
2777		return -EPERM;
2778
2779replay:
 
2780	err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
2781				     rtm_tca_policy, extack);
2782	if (err < 0)
2783		return err;
2784
2785	t = nlmsg_data(n);
2786	parent = t->tcm_parent;
2787	cl = 0;
2788
2789	block = tcf_block_find(net, &q, &parent, &cl,
2790			       t->tcm_ifindex, t->tcm_block_index, extack);
2791	if (IS_ERR(block))
2792		return PTR_ERR(block);
2793
2794	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2795	if (chain_index > TC_ACT_EXT_VAL_MASK) {
2796		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2797		err = -EINVAL;
2798		goto errout_block;
2799	}
2800
2801	mutex_lock(&block->lock);
2802	chain = tcf_chain_lookup(block, chain_index);
2803	if (n->nlmsg_type == RTM_NEWCHAIN) {
2804		if (chain) {
2805			if (tcf_chain_held_by_acts_only(chain)) {
2806				/* The chain exists only because there is
2807				 * some action referencing it.
2808				 */
2809				tcf_chain_hold(chain);
2810			} else {
2811				NL_SET_ERR_MSG(extack, "Filter chain already exists");
2812				err = -EEXIST;
2813				goto errout_block_locked;
2814			}
2815		} else {
2816			if (!(n->nlmsg_flags & NLM_F_CREATE)) {
2817				NL_SET_ERR_MSG(extack, "Need both RTM_NEWCHAIN and NLM_F_CREATE to create a new chain");
2818				err = -ENOENT;
2819				goto errout_block_locked;
2820			}
2821			chain = tcf_chain_create(block, chain_index);
2822			if (!chain) {
2823				NL_SET_ERR_MSG(extack, "Failed to create filter chain");
2824				err = -ENOMEM;
2825				goto errout_block_locked;
2826			}
2827		}
2828	} else {
2829		if (!chain || tcf_chain_held_by_acts_only(chain)) {
2830			NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
2831			err = -EINVAL;
2832			goto errout_block_locked;
2833		}
2834		tcf_chain_hold(chain);
2835	}
2836
2837	if (n->nlmsg_type == RTM_NEWCHAIN) {
2838		/* Modifying chain requires holding parent block lock. In case
2839		 * the chain was successfully added, take a reference to the
2840		 * chain. This ensures that an empty chain does not disappear at
2841		 * the end of this function.
2842		 */
2843		tcf_chain_hold(chain);
2844		chain->explicitly_created = true;
2845	}
2846	mutex_unlock(&block->lock);
2847
2848	switch (n->nlmsg_type) {
2849	case RTM_NEWCHAIN:
2850		err = tc_chain_tmplt_add(chain, net, tca, extack);
2851		if (err) {
2852			tcf_chain_put_explicitly_created(chain);
2853			goto errout;
2854		}
2855
2856		tc_chain_notify(chain, NULL, 0, NLM_F_CREATE | NLM_F_EXCL,
2857				RTM_NEWCHAIN, false);
2858		break;
2859	case RTM_DELCHAIN:
2860		tfilter_notify_chain(net, skb, block, q, parent, n,
2861				     chain, RTM_DELTFILTER, true);
2862		/* Flush the chain first as the user requested chain removal. */
2863		tcf_chain_flush(chain, true);
2864		/* In case the chain was successfully deleted, put a reference
2865		 * to the chain previously taken during addition.
2866		 */
2867		tcf_chain_put_explicitly_created(chain);
2868		break;
2869	case RTM_GETCHAIN:
2870		err = tc_chain_notify(chain, skb, n->nlmsg_seq,
2871				      n->nlmsg_seq, n->nlmsg_type, true);
2872		if (err < 0)
2873			NL_SET_ERR_MSG(extack, "Failed to send chain notify message");
2874		break;
2875	default:
2876		err = -EOPNOTSUPP;
2877		NL_SET_ERR_MSG(extack, "Unsupported message type");
2878		goto errout;
2879	}
2880
2881errout:
2882	tcf_chain_put(chain);
2883errout_block:
2884	tcf_block_release(q, block, true);
2885	if (err == -EAGAIN)
2886		/* Replay the request. */
2887		goto replay;
2888	return err;
2889
2890errout_block_locked:
2891	mutex_unlock(&block->lock);
2892	goto errout_block;
2893}
2894
2895/* called with RTNL */
2896static int tc_dump_chain(struct sk_buff *skb, struct netlink_callback *cb)
2897{
2898	struct net *net = sock_net(skb->sk);
2899	struct nlattr *tca[TCA_MAX + 1];
2900	struct Qdisc *q = NULL;
2901	struct tcf_block *block;
2902	struct tcmsg *tcm = nlmsg_data(cb->nlh);
2903	struct tcf_chain *chain;
2904	long index_start;
2905	long index;
2906	u32 parent;
2907	int err;
2908
2909	if (nlmsg_len(cb->nlh) < sizeof(*tcm))
2910		return skb->len;
2911
2912	err = nlmsg_parse_deprecated(cb->nlh, sizeof(*tcm), tca, TCA_MAX,
2913				     rtm_tca_policy, cb->extack);
2914	if (err)
2915		return err;
2916
2917	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
2918		block = tcf_block_refcnt_get(net, tcm->tcm_block_index);
2919		if (!block)
2920			goto out;
2921		/* If we work with block index, q is NULL and parent value
2922		 * will never be used in the following code. The check
2923		 * in tcf_fill_node prevents it. However, compiler does not
2924		 * see that far, so set parent to zero to silence the warning
2925		 * about parent being uninitialized.
2926		 */
2927		parent = 0;
2928	} else {
2929		const struct Qdisc_class_ops *cops;
2930		struct net_device *dev;
2931		unsigned long cl = 0;
2932
2933		dev = __dev_get_by_index(net, tcm->tcm_ifindex);
2934		if (!dev)
2935			return skb->len;
2936
2937		parent = tcm->tcm_parent;
2938		if (!parent) {
2939			q = dev->qdisc;
2940			parent = q->handle;
2941		} else {
2942			q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
2943		}
2944		if (!q)
2945			goto out;
2946		cops = q->ops->cl_ops;
2947		if (!cops)
2948			goto out;
2949		if (!cops->tcf_block)
2950			goto out;
2951		if (TC_H_MIN(tcm->tcm_parent)) {
2952			cl = cops->find(q, tcm->tcm_parent);
2953			if (cl == 0)
2954				goto out;
2955		}
2956		block = cops->tcf_block(q, cl, NULL);
2957		if (!block)
2958			goto out;
2959		if (tcf_block_shared(block))
2960			q = NULL;
2961	}
2962
2963	index_start = cb->args[0];
2964	index = 0;
2965
2966	mutex_lock(&block->lock);
2967	list_for_each_entry(chain, &block->chain_list, list) {
2968		if ((tca[TCA_CHAIN] &&
2969		     nla_get_u32(tca[TCA_CHAIN]) != chain->index))
2970			continue;
2971		if (index < index_start) {
2972			index++;
2973			continue;
2974		}
2975		if (tcf_chain_held_by_acts_only(chain))
2976			continue;
2977		err = tc_chain_fill_node(chain->tmplt_ops, chain->tmplt_priv,
2978					 chain->index, net, skb, block,
2979					 NETLINK_CB(cb->skb).portid,
2980					 cb->nlh->nlmsg_seq, NLM_F_MULTI,
2981					 RTM_NEWCHAIN);
2982		if (err <= 0)
2983			break;
2984		index++;
2985	}
2986	mutex_unlock(&block->lock);
2987
2988	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK)
2989		tcf_block_refcnt_put(block, true);
2990	cb->args[0] = index;
2991
2992out:
2993	/* If we did no progress, the error (EMSGSIZE) is real */
2994	if (skb->len == 0 && err)
2995		return err;
2996	return skb->len;
2997}
2998
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2999void tcf_exts_destroy(struct tcf_exts *exts)
3000{
 
 
3001#ifdef CONFIG_NET_CLS_ACT
3002	if (exts->actions) {
3003		tcf_action_destroy(exts->actions, TCA_ACT_UNBIND);
3004		kfree(exts->actions);
3005	}
3006	exts->nr_actions = 0;
3007#endif
3008}
3009EXPORT_SYMBOL(tcf_exts_destroy);
3010
3011int tcf_exts_validate(struct net *net, struct tcf_proto *tp, struct nlattr **tb,
3012		      struct nlattr *rate_tlv, struct tcf_exts *exts, bool ovr,
3013		      bool rtnl_held, struct netlink_ext_ack *extack)
3014{
3015#ifdef CONFIG_NET_CLS_ACT
3016	{
 
3017		struct tc_action *act;
3018		size_t attr_size = 0;
3019
3020		if (exts->police && tb[exts->police]) {
 
 
 
 
 
 
 
3021			act = tcf_action_init_1(net, tp, tb[exts->police],
3022						rate_tlv, "police", ovr,
3023						TCA_ACT_BIND, rtnl_held,
3024						extack);
 
3025			if (IS_ERR(act))
3026				return PTR_ERR(act);
3027
3028			act->type = exts->type = TCA_OLD_COMPAT;
3029			exts->actions[0] = act;
3030			exts->nr_actions = 1;
 
3031		} else if (exts->action && tb[exts->action]) {
3032			int err;
3033
 
3034			err = tcf_action_init(net, tp, tb[exts->action],
3035					      rate_tlv, NULL, ovr, TCA_ACT_BIND,
3036					      exts->actions, &attr_size,
3037					      rtnl_held, extack);
3038			if (err < 0)
3039				return err;
3040			exts->nr_actions = err;
3041		}
3042	}
3043#else
3044	if ((exts->action && tb[exts->action]) ||
3045	    (exts->police && tb[exts->police])) {
3046		NL_SET_ERR_MSG(extack, "Classifier actions are not supported per compile options (CONFIG_NET_CLS_ACT)");
3047		return -EOPNOTSUPP;
3048	}
3049#endif
3050
3051	return 0;
3052}
 
 
 
 
 
 
 
 
 
3053EXPORT_SYMBOL(tcf_exts_validate);
3054
3055void tcf_exts_change(struct tcf_exts *dst, struct tcf_exts *src)
3056{
3057#ifdef CONFIG_NET_CLS_ACT
3058	struct tcf_exts old = *dst;
3059
3060	*dst = *src;
3061	tcf_exts_destroy(&old);
3062#endif
3063}
3064EXPORT_SYMBOL(tcf_exts_change);
3065
3066#ifdef CONFIG_NET_CLS_ACT
3067static struct tc_action *tcf_exts_first_act(struct tcf_exts *exts)
3068{
3069	if (exts->nr_actions == 0)
3070		return NULL;
3071	else
3072		return exts->actions[0];
3073}
3074#endif
3075
3076int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts)
3077{
3078#ifdef CONFIG_NET_CLS_ACT
3079	struct nlattr *nest;
3080
3081	if (exts->action && tcf_exts_has_actions(exts)) {
3082		/*
3083		 * again for backward compatible mode - we want
3084		 * to work with both old and new modes of entering
3085		 * tc data even if iproute2  was newer - jhs
3086		 */
3087		if (exts->type != TCA_OLD_COMPAT) {
3088			nest = nla_nest_start_noflag(skb, exts->action);
3089			if (nest == NULL)
3090				goto nla_put_failure;
3091
3092			if (tcf_action_dump(skb, exts->actions, 0, 0) < 0)
 
3093				goto nla_put_failure;
3094			nla_nest_end(skb, nest);
3095		} else if (exts->police) {
3096			struct tc_action *act = tcf_exts_first_act(exts);
3097			nest = nla_nest_start_noflag(skb, exts->police);
3098			if (nest == NULL || !act)
3099				goto nla_put_failure;
3100			if (tcf_action_dump_old(skb, act, 0, 0) < 0)
3101				goto nla_put_failure;
3102			nla_nest_end(skb, nest);
3103		}
3104	}
3105	return 0;
3106
3107nla_put_failure:
3108	nla_nest_cancel(skb, nest);
3109	return -1;
3110#else
3111	return 0;
3112#endif
3113}
3114EXPORT_SYMBOL(tcf_exts_dump);
3115
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3116
3117int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts)
3118{
3119#ifdef CONFIG_NET_CLS_ACT
3120	struct tc_action *a = tcf_exts_first_act(exts);
3121	if (a != NULL && tcf_action_copy_stats(skb, a, 1) < 0)
3122		return -1;
3123#endif
3124	return 0;
3125}
3126EXPORT_SYMBOL(tcf_exts_dump_stats);
3127
3128static void tcf_block_offload_inc(struct tcf_block *block, u32 *flags)
3129{
3130	if (*flags & TCA_CLS_FLAGS_IN_HW)
3131		return;
3132	*flags |= TCA_CLS_FLAGS_IN_HW;
3133	atomic_inc(&block->offloadcnt);
3134}
3135
3136static void tcf_block_offload_dec(struct tcf_block *block, u32 *flags)
3137{
3138	if (!(*flags & TCA_CLS_FLAGS_IN_HW))
3139		return;
3140	*flags &= ~TCA_CLS_FLAGS_IN_HW;
3141	atomic_dec(&block->offloadcnt);
3142}
3143
3144static void tc_cls_offload_cnt_update(struct tcf_block *block,
3145				      struct tcf_proto *tp, u32 *cnt,
3146				      u32 *flags, u32 diff, bool add)
3147{
3148	lockdep_assert_held(&block->cb_lock);
3149
3150	spin_lock(&tp->lock);
3151	if (add) {
3152		if (!*cnt)
3153			tcf_block_offload_inc(block, flags);
3154		*cnt += diff;
3155	} else {
3156		*cnt -= diff;
3157		if (!*cnt)
3158			tcf_block_offload_dec(block, flags);
3159	}
3160	spin_unlock(&tp->lock);
3161}
3162
3163static void
3164tc_cls_offload_cnt_reset(struct tcf_block *block, struct tcf_proto *tp,
3165			 u32 *cnt, u32 *flags)
3166{
3167	lockdep_assert_held(&block->cb_lock);
3168
3169	spin_lock(&tp->lock);
3170	tcf_block_offload_dec(block, flags);
3171	*cnt = 0;
3172	spin_unlock(&tp->lock);
3173}
3174
3175static int
3176__tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type,
3177		   void *type_data, bool err_stop)
3178{
3179	struct flow_block_cb *block_cb;
3180	int ok_count = 0;
3181	int err;
3182
3183	list_for_each_entry(block_cb, &block->flow_block.cb_list, list) {
3184		err = block_cb->cb(type, type_data, block_cb->cb_priv);
3185		if (err) {
3186			if (err_stop)
3187				return err;
3188		} else {
3189			ok_count++;
3190		}
3191	}
3192	return ok_count;
3193}
3194
3195int tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type,
3196		     void *type_data, bool err_stop, bool rtnl_held)
3197{
3198	bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3199	int ok_count;
3200
3201retry:
3202	if (take_rtnl)
3203		rtnl_lock();
3204	down_read(&block->cb_lock);
3205	/* Need to obtain rtnl lock if block is bound to devs that require it.
3206	 * In block bind code cb_lock is obtained while holding rtnl, so we must
3207	 * obtain the locks in same order here.
3208	 */
3209	if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3210		up_read(&block->cb_lock);
3211		take_rtnl = true;
3212		goto retry;
3213	}
3214
3215	ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3216
3217	up_read(&block->cb_lock);
3218	if (take_rtnl)
3219		rtnl_unlock();
3220	return ok_count;
3221}
3222EXPORT_SYMBOL(tc_setup_cb_call);
3223
3224/* Non-destructive filter add. If filter that wasn't already in hardware is
3225 * successfully offloaded, increment block offloads counter. On failure,
3226 * previously offloaded filter is considered to be intact and offloads counter
3227 * is not decremented.
3228 */
3229
3230int tc_setup_cb_add(struct tcf_block *block, struct tcf_proto *tp,
3231		    enum tc_setup_type type, void *type_data, bool err_stop,
3232		    u32 *flags, unsigned int *in_hw_count, bool rtnl_held)
3233{
3234	bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3235	int ok_count;
3236
3237retry:
3238	if (take_rtnl)
3239		rtnl_lock();
3240	down_read(&block->cb_lock);
3241	/* Need to obtain rtnl lock if block is bound to devs that require it.
3242	 * In block bind code cb_lock is obtained while holding rtnl, so we must
3243	 * obtain the locks in same order here.
3244	 */
3245	if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3246		up_read(&block->cb_lock);
3247		take_rtnl = true;
3248		goto retry;
3249	}
3250
3251	/* Make sure all netdevs sharing this block are offload-capable. */
3252	if (block->nooffloaddevcnt && err_stop) {
3253		ok_count = -EOPNOTSUPP;
3254		goto err_unlock;
3255	}
3256
3257	ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3258	if (ok_count < 0)
3259		goto err_unlock;
3260
3261	if (tp->ops->hw_add)
3262		tp->ops->hw_add(tp, type_data);
3263	if (ok_count > 0)
3264		tc_cls_offload_cnt_update(block, tp, in_hw_count, flags,
3265					  ok_count, true);
3266err_unlock:
3267	up_read(&block->cb_lock);
3268	if (take_rtnl)
3269		rtnl_unlock();
3270	return ok_count < 0 ? ok_count : 0;
3271}
3272EXPORT_SYMBOL(tc_setup_cb_add);
3273
3274/* Destructive filter replace. If filter that wasn't already in hardware is
3275 * successfully offloaded, increment block offload counter. On failure,
3276 * previously offloaded filter is considered to be destroyed and offload counter
3277 * is decremented.
3278 */
3279
3280int tc_setup_cb_replace(struct tcf_block *block, struct tcf_proto *tp,
3281			enum tc_setup_type type, void *type_data, bool err_stop,
3282			u32 *old_flags, unsigned int *old_in_hw_count,
3283			u32 *new_flags, unsigned int *new_in_hw_count,
3284			bool rtnl_held)
3285{
3286	bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3287	int ok_count;
3288
3289retry:
3290	if (take_rtnl)
3291		rtnl_lock();
3292	down_read(&block->cb_lock);
3293	/* Need to obtain rtnl lock if block is bound to devs that require it.
3294	 * In block bind code cb_lock is obtained while holding rtnl, so we must
3295	 * obtain the locks in same order here.
3296	 */
3297	if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3298		up_read(&block->cb_lock);
3299		take_rtnl = true;
3300		goto retry;
3301	}
3302
3303	/* Make sure all netdevs sharing this block are offload-capable. */
3304	if (block->nooffloaddevcnt && err_stop) {
3305		ok_count = -EOPNOTSUPP;
3306		goto err_unlock;
3307	}
3308
3309	tc_cls_offload_cnt_reset(block, tp, old_in_hw_count, old_flags);
3310	if (tp->ops->hw_del)
3311		tp->ops->hw_del(tp, type_data);
3312
3313	ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3314	if (ok_count < 0)
3315		goto err_unlock;
3316
3317	if (tp->ops->hw_add)
3318		tp->ops->hw_add(tp, type_data);
3319	if (ok_count > 0)
3320		tc_cls_offload_cnt_update(block, tp, new_in_hw_count,
3321					  new_flags, ok_count, true);
3322err_unlock:
3323	up_read(&block->cb_lock);
3324	if (take_rtnl)
3325		rtnl_unlock();
3326	return ok_count < 0 ? ok_count : 0;
3327}
3328EXPORT_SYMBOL(tc_setup_cb_replace);
3329
3330/* Destroy filter and decrement block offload counter, if filter was previously
3331 * offloaded.
3332 */
3333
3334int tc_setup_cb_destroy(struct tcf_block *block, struct tcf_proto *tp,
3335			enum tc_setup_type type, void *type_data, bool err_stop,
3336			u32 *flags, unsigned int *in_hw_count, bool rtnl_held)
3337{
3338	bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3339	int ok_count;
3340
3341retry:
3342	if (take_rtnl)
3343		rtnl_lock();
3344	down_read(&block->cb_lock);
3345	/* Need to obtain rtnl lock if block is bound to devs that require it.
3346	 * In block bind code cb_lock is obtained while holding rtnl, so we must
3347	 * obtain the locks in same order here.
3348	 */
3349	if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3350		up_read(&block->cb_lock);
3351		take_rtnl = true;
3352		goto retry;
3353	}
3354
3355	ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3356
3357	tc_cls_offload_cnt_reset(block, tp, in_hw_count, flags);
3358	if (tp->ops->hw_del)
3359		tp->ops->hw_del(tp, type_data);
3360
3361	up_read(&block->cb_lock);
3362	if (take_rtnl)
3363		rtnl_unlock();
3364	return ok_count < 0 ? ok_count : 0;
3365}
3366EXPORT_SYMBOL(tc_setup_cb_destroy);
3367
3368int tc_setup_cb_reoffload(struct tcf_block *block, struct tcf_proto *tp,
3369			  bool add, flow_setup_cb_t *cb,
3370			  enum tc_setup_type type, void *type_data,
3371			  void *cb_priv, u32 *flags, unsigned int *in_hw_count)
3372{
3373	int err = cb(type, type_data, cb_priv);
3374
3375	if (err) {
3376		if (add && tc_skip_sw(*flags))
3377			return err;
3378	} else {
3379		tc_cls_offload_cnt_update(block, tp, in_hw_count, flags, 1,
3380					  add);
3381	}
3382
3383	return 0;
3384}
3385EXPORT_SYMBOL(tc_setup_cb_reoffload);
3386
3387void tc_cleanup_flow_action(struct flow_action *flow_action)
 
3388{
3389	struct flow_action_entry *entry;
3390	int i;
3391
3392	flow_action_for_each(i, entry, flow_action)
3393		if (entry->destructor)
3394			entry->destructor(entry->destructor_priv);
 
 
 
 
 
 
 
 
3395}
3396EXPORT_SYMBOL(tc_cleanup_flow_action);
3397
3398static void tcf_mirred_get_dev(struct flow_action_entry *entry,
3399			       const struct tc_action *act)
3400{
3401#ifdef CONFIG_NET_CLS_ACT
3402	entry->dev = act->ops->get_dev(act, &entry->destructor);
3403	if (!entry->dev)
3404		return;
3405	entry->destructor_priv = entry->dev;
3406#endif
3407}
3408
3409static void tcf_tunnel_encap_put_tunnel(void *priv)
3410{
3411	struct ip_tunnel_info *tunnel = priv;
3412
3413	kfree(tunnel);
3414}
3415
3416static int tcf_tunnel_encap_get_tunnel(struct flow_action_entry *entry,
3417				       const struct tc_action *act)
3418{
3419	entry->tunnel = tcf_tunnel_info_copy(act);
3420	if (!entry->tunnel)
3421		return -ENOMEM;
3422	entry->destructor = tcf_tunnel_encap_put_tunnel;
3423	entry->destructor_priv = entry->tunnel;
3424	return 0;
3425}
 
3426
3427static void tcf_sample_get_group(struct flow_action_entry *entry,
3428				 const struct tc_action *act)
 
 
3429{
3430#ifdef CONFIG_NET_CLS_ACT
3431	entry->sample.psample_group =
3432		act->ops->get_psample_group(act, &entry->destructor);
3433	entry->destructor_priv = entry->sample.psample_group;
 
 
 
 
 
 
3434#endif
3435}
3436
3437int tc_setup_flow_action(struct flow_action *flow_action,
3438			 const struct tcf_exts *exts, bool rtnl_held)
 
 
3439{
3440	const struct tc_action *act;
3441	int i, j, k, err = 0;
3442
3443	if (!exts)
3444		return 0;
 
3445
3446	if (!rtnl_held)
3447		rtnl_lock();
3448
3449	j = 0;
3450	tcf_exts_for_each_action(i, act, exts) {
3451		struct flow_action_entry *entry;
3452
3453		entry = &flow_action->entries[j];
3454		if (is_tcf_gact_ok(act)) {
3455			entry->id = FLOW_ACTION_ACCEPT;
3456		} else if (is_tcf_gact_shot(act)) {
3457			entry->id = FLOW_ACTION_DROP;
3458		} else if (is_tcf_gact_trap(act)) {
3459			entry->id = FLOW_ACTION_TRAP;
3460		} else if (is_tcf_gact_goto_chain(act)) {
3461			entry->id = FLOW_ACTION_GOTO;
3462			entry->chain_index = tcf_gact_goto_chain_index(act);
3463		} else if (is_tcf_mirred_egress_redirect(act)) {
3464			entry->id = FLOW_ACTION_REDIRECT;
3465			tcf_mirred_get_dev(entry, act);
3466		} else if (is_tcf_mirred_egress_mirror(act)) {
3467			entry->id = FLOW_ACTION_MIRRED;
3468			tcf_mirred_get_dev(entry, act);
3469		} else if (is_tcf_mirred_ingress_redirect(act)) {
3470			entry->id = FLOW_ACTION_REDIRECT_INGRESS;
3471			tcf_mirred_get_dev(entry, act);
3472		} else if (is_tcf_mirred_ingress_mirror(act)) {
3473			entry->id = FLOW_ACTION_MIRRED_INGRESS;
3474			tcf_mirred_get_dev(entry, act);
3475		} else if (is_tcf_vlan(act)) {
3476			switch (tcf_vlan_action(act)) {
3477			case TCA_VLAN_ACT_PUSH:
3478				entry->id = FLOW_ACTION_VLAN_PUSH;
3479				entry->vlan.vid = tcf_vlan_push_vid(act);
3480				entry->vlan.proto = tcf_vlan_push_proto(act);
3481				entry->vlan.prio = tcf_vlan_push_prio(act);
3482				break;
3483			case TCA_VLAN_ACT_POP:
3484				entry->id = FLOW_ACTION_VLAN_POP;
3485				break;
3486			case TCA_VLAN_ACT_MODIFY:
3487				entry->id = FLOW_ACTION_VLAN_MANGLE;
3488				entry->vlan.vid = tcf_vlan_push_vid(act);
3489				entry->vlan.proto = tcf_vlan_push_proto(act);
3490				entry->vlan.prio = tcf_vlan_push_prio(act);
3491				break;
3492			default:
3493				err = -EOPNOTSUPP;
3494				goto err_out;
3495			}
3496		} else if (is_tcf_tunnel_set(act)) {
3497			entry->id = FLOW_ACTION_TUNNEL_ENCAP;
3498			err = tcf_tunnel_encap_get_tunnel(entry, act);
3499			if (err)
3500				goto err_out;
3501		} else if (is_tcf_tunnel_release(act)) {
3502			entry->id = FLOW_ACTION_TUNNEL_DECAP;
3503		} else if (is_tcf_pedit(act)) {
3504			for (k = 0; k < tcf_pedit_nkeys(act); k++) {
3505				switch (tcf_pedit_cmd(act, k)) {
3506				case TCA_PEDIT_KEY_EX_CMD_SET:
3507					entry->id = FLOW_ACTION_MANGLE;
3508					break;
3509				case TCA_PEDIT_KEY_EX_CMD_ADD:
3510					entry->id = FLOW_ACTION_ADD;
3511					break;
3512				default:
3513					err = -EOPNOTSUPP;
3514					goto err_out;
3515				}
3516				entry->mangle.htype = tcf_pedit_htype(act, k);
3517				entry->mangle.mask = tcf_pedit_mask(act, k);
3518				entry->mangle.val = tcf_pedit_val(act, k);
3519				entry->mangle.offset = tcf_pedit_offset(act, k);
3520				entry = &flow_action->entries[++j];
3521			}
3522		} else if (is_tcf_csum(act)) {
3523			entry->id = FLOW_ACTION_CSUM;
3524			entry->csum_flags = tcf_csum_update_flags(act);
3525		} else if (is_tcf_skbedit_mark(act)) {
3526			entry->id = FLOW_ACTION_MARK;
3527			entry->mark = tcf_skbedit_mark(act);
3528		} else if (is_tcf_sample(act)) {
3529			entry->id = FLOW_ACTION_SAMPLE;
3530			entry->sample.trunc_size = tcf_sample_trunc_size(act);
3531			entry->sample.truncate = tcf_sample_truncate(act);
3532			entry->sample.rate = tcf_sample_rate(act);
3533			tcf_sample_get_group(entry, act);
3534		} else if (is_tcf_police(act)) {
3535			entry->id = FLOW_ACTION_POLICE;
3536			entry->police.burst = tcf_police_tcfp_burst(act);
3537			entry->police.rate_bytes_ps =
3538				tcf_police_rate_bytes_ps(act);
3539		} else if (is_tcf_ct(act)) {
3540			entry->id = FLOW_ACTION_CT;
3541			entry->ct.action = tcf_ct_action(act);
3542			entry->ct.zone = tcf_ct_zone(act);
3543		} else if (is_tcf_mpls(act)) {
3544			switch (tcf_mpls_action(act)) {
3545			case TCA_MPLS_ACT_PUSH:
3546				entry->id = FLOW_ACTION_MPLS_PUSH;
3547				entry->mpls_push.proto = tcf_mpls_proto(act);
3548				entry->mpls_push.label = tcf_mpls_label(act);
3549				entry->mpls_push.tc = tcf_mpls_tc(act);
3550				entry->mpls_push.bos = tcf_mpls_bos(act);
3551				entry->mpls_push.ttl = tcf_mpls_ttl(act);
3552				break;
3553			case TCA_MPLS_ACT_POP:
3554				entry->id = FLOW_ACTION_MPLS_POP;
3555				entry->mpls_pop.proto = tcf_mpls_proto(act);
3556				break;
3557			case TCA_MPLS_ACT_MODIFY:
3558				entry->id = FLOW_ACTION_MPLS_MANGLE;
3559				entry->mpls_mangle.label = tcf_mpls_label(act);
3560				entry->mpls_mangle.tc = tcf_mpls_tc(act);
3561				entry->mpls_mangle.bos = tcf_mpls_bos(act);
3562				entry->mpls_mangle.ttl = tcf_mpls_ttl(act);
3563				break;
3564			default:
3565				goto err_out;
3566			}
3567		} else if (is_tcf_skbedit_ptype(act)) {
3568			entry->id = FLOW_ACTION_PTYPE;
3569			entry->ptype = tcf_skbedit_ptype(act);
3570		} else {
3571			err = -EOPNOTSUPP;
3572			goto err_out;
3573		}
3574
3575		if (!is_tcf_pedit(act))
3576			j++;
 
3577	}
3578
3579err_out:
3580	if (!rtnl_held)
3581		rtnl_unlock();
3582
3583	if (err)
3584		tc_cleanup_flow_action(flow_action);
3585
3586	return err;
 
 
 
3587}
3588EXPORT_SYMBOL(tc_setup_flow_action);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3589
3590unsigned int tcf_exts_num_actions(struct tcf_exts *exts)
3591{
3592	unsigned int num_acts = 0;
3593	struct tc_action *act;
3594	int i;
3595
3596	tcf_exts_for_each_action(i, act, exts) {
3597		if (is_tcf_pedit(act))
3598			num_acts += tcf_pedit_nkeys(act);
3599		else
3600			num_acts++;
3601	}
3602	return num_acts;
3603}
3604EXPORT_SYMBOL(tcf_exts_num_actions);
3605
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3606static __net_init int tcf_net_init(struct net *net)
3607{
3608	struct tcf_net *tn = net_generic(net, tcf_net_id);
3609
3610	spin_lock_init(&tn->idr_lock);
3611	idr_init(&tn->idr);
3612	return 0;
3613}
3614
3615static void __net_exit tcf_net_exit(struct net *net)
3616{
3617	struct tcf_net *tn = net_generic(net, tcf_net_id);
3618
3619	idr_destroy(&tn->idr);
3620}
3621
3622static struct pernet_operations tcf_net_ops = {
3623	.init = tcf_net_init,
3624	.exit = tcf_net_exit,
3625	.id   = &tcf_net_id,
3626	.size = sizeof(struct tcf_net),
3627};
3628
3629static struct flow_indr_block_ing_entry block_ing_entry = {
3630	.cb = tc_indr_block_get_and_ing_cmd,
3631	.list = LIST_HEAD_INIT(block_ing_entry.list),
3632};
3633
3634static int __init tc_filter_init(void)
3635{
3636	int err;
3637
3638	tc_filter_wq = alloc_ordered_workqueue("tc_filter_workqueue", 0);
3639	if (!tc_filter_wq)
3640		return -ENOMEM;
3641
3642	err = register_pernet_subsys(&tcf_net_ops);
3643	if (err)
3644		goto err_register_pernet_subsys;
3645
3646	flow_indr_add_block_ing_cb(&block_ing_entry);
3647
3648	rtnl_register(PF_UNSPEC, RTM_NEWTFILTER, tc_new_tfilter, NULL,
3649		      RTNL_FLAG_DOIT_UNLOCKED);
3650	rtnl_register(PF_UNSPEC, RTM_DELTFILTER, tc_del_tfilter, NULL,
3651		      RTNL_FLAG_DOIT_UNLOCKED);
3652	rtnl_register(PF_UNSPEC, RTM_GETTFILTER, tc_get_tfilter,
3653		      tc_dump_tfilter, RTNL_FLAG_DOIT_UNLOCKED);
3654	rtnl_register(PF_UNSPEC, RTM_NEWCHAIN, tc_ctl_chain, NULL, 0);
3655	rtnl_register(PF_UNSPEC, RTM_DELCHAIN, tc_ctl_chain, NULL, 0);
3656	rtnl_register(PF_UNSPEC, RTM_GETCHAIN, tc_ctl_chain,
3657		      tc_dump_chain, 0);
3658
3659	return 0;
3660
3661err_register_pernet_subsys:
3662	destroy_workqueue(tc_filter_wq);
3663	return err;
3664}
3665
3666subsys_initcall(tc_filter_init);
v6.8
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * net/sched/cls_api.c	Packet classifier API.
   4 *
   5 * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
   6 *
   7 * Changes:
   8 *
   9 * Eduardo J. Blanco <ejbs@netlabs.com.uy> :990222: kmod support
  10 */
  11
  12#include <linux/module.h>
  13#include <linux/types.h>
  14#include <linux/kernel.h>
  15#include <linux/string.h>
  16#include <linux/errno.h>
  17#include <linux/err.h>
  18#include <linux/skbuff.h>
  19#include <linux/init.h>
  20#include <linux/kmod.h>
  21#include <linux/slab.h>
  22#include <linux/idr.h>
 
  23#include <linux/jhash.h>
  24#include <linux/rculist.h>
  25#include <linux/rhashtable.h>
  26#include <net/net_namespace.h>
  27#include <net/sock.h>
  28#include <net/netlink.h>
  29#include <net/pkt_sched.h>
  30#include <net/pkt_cls.h>
  31#include <net/tc_act/tc_pedit.h>
  32#include <net/tc_act/tc_mirred.h>
  33#include <net/tc_act/tc_vlan.h>
  34#include <net/tc_act/tc_tunnel_key.h>
  35#include <net/tc_act/tc_csum.h>
  36#include <net/tc_act/tc_gact.h>
  37#include <net/tc_act/tc_police.h>
  38#include <net/tc_act/tc_sample.h>
  39#include <net/tc_act/tc_skbedit.h>
  40#include <net/tc_act/tc_ct.h>
  41#include <net/tc_act/tc_mpls.h>
  42#include <net/tc_act/tc_gate.h>
  43#include <net/flow_offload.h>
  44#include <net/tc_wrapper.h>
 
  45
  46/* The list of all installed classifier types */
  47static LIST_HEAD(tcf_proto_base);
  48
  49/* Protects list of registered TC modules. It is pure SMP lock. */
  50static DEFINE_RWLOCK(cls_mod_lock);
  51
  52static struct xarray tcf_exts_miss_cookies_xa;
  53struct tcf_exts_miss_cookie_node {
  54	const struct tcf_chain *chain;
  55	const struct tcf_proto *tp;
  56	const struct tcf_exts *exts;
  57	u32 chain_index;
  58	u32 tp_prio;
  59	u32 handle;
  60	u32 miss_cookie_base;
  61	struct rcu_head rcu;
  62};
  63
  64/* Each tc action entry cookie will be comprised of 32bit miss_cookie_base +
  65 * action index in the exts tc actions array.
  66 */
  67union tcf_exts_miss_cookie {
  68	struct {
  69		u32 miss_cookie_base;
  70		u32 act_index;
  71	};
  72	u64 miss_cookie;
  73};
  74
  75#if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
  76static int
  77tcf_exts_miss_cookie_base_alloc(struct tcf_exts *exts, struct tcf_proto *tp,
  78				u32 handle)
  79{
  80	struct tcf_exts_miss_cookie_node *n;
  81	static u32 next;
  82	int err;
  83
  84	if (WARN_ON(!handle || !tp->ops->get_exts))
  85		return -EINVAL;
  86
  87	n = kzalloc(sizeof(*n), GFP_KERNEL);
  88	if (!n)
  89		return -ENOMEM;
  90
  91	n->chain_index = tp->chain->index;
  92	n->chain = tp->chain;
  93	n->tp_prio = tp->prio;
  94	n->tp = tp;
  95	n->exts = exts;
  96	n->handle = handle;
  97
  98	err = xa_alloc_cyclic(&tcf_exts_miss_cookies_xa, &n->miss_cookie_base,
  99			      n, xa_limit_32b, &next, GFP_KERNEL);
 100	if (err)
 101		goto err_xa_alloc;
 102
 103	exts->miss_cookie_node = n;
 104	return 0;
 105
 106err_xa_alloc:
 107	kfree(n);
 108	return err;
 109}
 110
 111static void tcf_exts_miss_cookie_base_destroy(struct tcf_exts *exts)
 112{
 113	struct tcf_exts_miss_cookie_node *n;
 114
 115	if (!exts->miss_cookie_node)
 116		return;
 117
 118	n = exts->miss_cookie_node;
 119	xa_erase(&tcf_exts_miss_cookies_xa, n->miss_cookie_base);
 120	kfree_rcu(n, rcu);
 121}
 122
 123static struct tcf_exts_miss_cookie_node *
 124tcf_exts_miss_cookie_lookup(u64 miss_cookie, int *act_index)
 125{
 126	union tcf_exts_miss_cookie mc = { .miss_cookie = miss_cookie, };
 127
 128	*act_index = mc.act_index;
 129	return xa_load(&tcf_exts_miss_cookies_xa, mc.miss_cookie_base);
 130}
 131#else /* IS_ENABLED(CONFIG_NET_TC_SKB_EXT) */
 132static int
 133tcf_exts_miss_cookie_base_alloc(struct tcf_exts *exts, struct tcf_proto *tp,
 134				u32 handle)
 135{
 136	return 0;
 137}
 138
 139static void tcf_exts_miss_cookie_base_destroy(struct tcf_exts *exts)
 140{
 141}
 142#endif /* IS_ENABLED(CONFIG_NET_TC_SKB_EXT) */
 143
 144static u64 tcf_exts_miss_cookie_get(u32 miss_cookie_base, int act_index)
 145{
 146	union tcf_exts_miss_cookie mc = { .act_index = act_index, };
 147
 148	if (!miss_cookie_base)
 149		return 0;
 150
 151	mc.miss_cookie_base = miss_cookie_base;
 152	return mc.miss_cookie;
 153}
 154
 155#ifdef CONFIG_NET_CLS_ACT
 156DEFINE_STATIC_KEY_FALSE(tc_skb_ext_tc);
 157EXPORT_SYMBOL(tc_skb_ext_tc);
 158
 159void tc_skb_ext_tc_enable(void)
 160{
 161	static_branch_inc(&tc_skb_ext_tc);
 162}
 163EXPORT_SYMBOL(tc_skb_ext_tc_enable);
 164
 165void tc_skb_ext_tc_disable(void)
 166{
 167	static_branch_dec(&tc_skb_ext_tc);
 168}
 169EXPORT_SYMBOL(tc_skb_ext_tc_disable);
 170#endif
 171
 172static u32 destroy_obj_hashfn(const struct tcf_proto *tp)
 173{
 174	return jhash_3words(tp->chain->index, tp->prio,
 175			    (__force __u32)tp->protocol, 0);
 176}
 177
 178static void tcf_proto_signal_destroying(struct tcf_chain *chain,
 179					struct tcf_proto *tp)
 180{
 181	struct tcf_block *block = chain->block;
 182
 183	mutex_lock(&block->proto_destroy_lock);
 184	hash_add_rcu(block->proto_destroy_ht, &tp->destroy_ht_node,
 185		     destroy_obj_hashfn(tp));
 186	mutex_unlock(&block->proto_destroy_lock);
 187}
 188
 189static bool tcf_proto_cmp(const struct tcf_proto *tp1,
 190			  const struct tcf_proto *tp2)
 191{
 192	return tp1->chain->index == tp2->chain->index &&
 193	       tp1->prio == tp2->prio &&
 194	       tp1->protocol == tp2->protocol;
 195}
 196
 197static bool tcf_proto_exists_destroying(struct tcf_chain *chain,
 198					struct tcf_proto *tp)
 199{
 200	u32 hash = destroy_obj_hashfn(tp);
 201	struct tcf_proto *iter;
 202	bool found = false;
 203
 204	rcu_read_lock();
 205	hash_for_each_possible_rcu(chain->block->proto_destroy_ht, iter,
 206				   destroy_ht_node, hash) {
 207		if (tcf_proto_cmp(tp, iter)) {
 208			found = true;
 209			break;
 210		}
 211	}
 212	rcu_read_unlock();
 213
 214	return found;
 215}
 216
 217static void
 218tcf_proto_signal_destroyed(struct tcf_chain *chain, struct tcf_proto *tp)
 219{
 220	struct tcf_block *block = chain->block;
 221
 222	mutex_lock(&block->proto_destroy_lock);
 223	if (hash_hashed(&tp->destroy_ht_node))
 224		hash_del_rcu(&tp->destroy_ht_node);
 225	mutex_unlock(&block->proto_destroy_lock);
 226}
 227
 228/* Find classifier type by string name */
 229
 230static const struct tcf_proto_ops *__tcf_proto_lookup_ops(const char *kind)
 231{
 232	const struct tcf_proto_ops *t, *res = NULL;
 233
 234	if (kind) {
 235		read_lock(&cls_mod_lock);
 236		list_for_each_entry(t, &tcf_proto_base, head) {
 237			if (strcmp(kind, t->kind) == 0) {
 238				if (try_module_get(t->owner))
 239					res = t;
 240				break;
 241			}
 242		}
 243		read_unlock(&cls_mod_lock);
 244	}
 245	return res;
 246}
 247
 248static const struct tcf_proto_ops *
 249tcf_proto_lookup_ops(const char *kind, bool rtnl_held,
 250		     struct netlink_ext_ack *extack)
 251{
 252	const struct tcf_proto_ops *ops;
 253
 254	ops = __tcf_proto_lookup_ops(kind);
 255	if (ops)
 256		return ops;
 257#ifdef CONFIG_MODULES
 258	if (rtnl_held)
 259		rtnl_unlock();
 260	request_module("cls_%s", kind);
 261	if (rtnl_held)
 262		rtnl_lock();
 263	ops = __tcf_proto_lookup_ops(kind);
 264	/* We dropped the RTNL semaphore in order to perform
 265	 * the module load. So, even if we succeeded in loading
 266	 * the module we have to replay the request. We indicate
 267	 * this using -EAGAIN.
 268	 */
 269	if (ops) {
 270		module_put(ops->owner);
 271		return ERR_PTR(-EAGAIN);
 272	}
 273#endif
 274	NL_SET_ERR_MSG(extack, "TC classifier not found");
 275	return ERR_PTR(-ENOENT);
 276}
 277
 278/* Register(unregister) new classifier type */
 279
 280int register_tcf_proto_ops(struct tcf_proto_ops *ops)
 281{
 282	struct tcf_proto_ops *t;
 283	int rc = -EEXIST;
 284
 285	write_lock(&cls_mod_lock);
 286	list_for_each_entry(t, &tcf_proto_base, head)
 287		if (!strcmp(ops->kind, t->kind))
 288			goto out;
 289
 290	list_add_tail(&ops->head, &tcf_proto_base);
 291	rc = 0;
 292out:
 293	write_unlock(&cls_mod_lock);
 294	return rc;
 295}
 296EXPORT_SYMBOL(register_tcf_proto_ops);
 297
 298static struct workqueue_struct *tc_filter_wq;
 299
 300void unregister_tcf_proto_ops(struct tcf_proto_ops *ops)
 301{
 302	struct tcf_proto_ops *t;
 303	int rc = -ENOENT;
 304
 305	/* Wait for outstanding call_rcu()s, if any, from a
 306	 * tcf_proto_ops's destroy() handler.
 307	 */
 308	rcu_barrier();
 309	flush_workqueue(tc_filter_wq);
 310
 311	write_lock(&cls_mod_lock);
 312	list_for_each_entry(t, &tcf_proto_base, head) {
 313		if (t == ops) {
 314			list_del(&t->head);
 315			rc = 0;
 316			break;
 317		}
 318	}
 319	write_unlock(&cls_mod_lock);
 320
 321	WARN(rc, "unregister tc filter kind(%s) failed %d\n", ops->kind, rc);
 322}
 323EXPORT_SYMBOL(unregister_tcf_proto_ops);
 324
 325bool tcf_queue_work(struct rcu_work *rwork, work_func_t func)
 326{
 327	INIT_RCU_WORK(rwork, func);
 328	return queue_rcu_work(tc_filter_wq, rwork);
 329}
 330EXPORT_SYMBOL(tcf_queue_work);
 331
 332/* Select new prio value from the range, managed by kernel. */
 333
 334static inline u32 tcf_auto_prio(struct tcf_proto *tp)
 335{
 336	u32 first = TC_H_MAKE(0xC0000000U, 0U);
 337
 338	if (tp)
 339		first = tp->prio - 1;
 340
 341	return TC_H_MAJ(first);
 342}
 343
 344static bool tcf_proto_check_kind(struct nlattr *kind, char *name)
 345{
 346	if (kind)
 347		return nla_strscpy(name, kind, IFNAMSIZ) < 0;
 348	memset(name, 0, IFNAMSIZ);
 349	return false;
 350}
 351
 352static bool tcf_proto_is_unlocked(const char *kind)
 353{
 354	const struct tcf_proto_ops *ops;
 355	bool ret;
 356
 357	if (strlen(kind) == 0)
 358		return false;
 359
 360	ops = tcf_proto_lookup_ops(kind, false, NULL);
 361	/* On error return false to take rtnl lock. Proto lookup/create
 362	 * functions will perform lookup again and properly handle errors.
 363	 */
 364	if (IS_ERR(ops))
 365		return false;
 366
 367	ret = !!(ops->flags & TCF_PROTO_OPS_DOIT_UNLOCKED);
 368	module_put(ops->owner);
 369	return ret;
 370}
 371
 372static struct tcf_proto *tcf_proto_create(const char *kind, u32 protocol,
 373					  u32 prio, struct tcf_chain *chain,
 374					  bool rtnl_held,
 375					  struct netlink_ext_ack *extack)
 376{
 377	struct tcf_proto *tp;
 378	int err;
 379
 380	tp = kzalloc(sizeof(*tp), GFP_KERNEL);
 381	if (!tp)
 382		return ERR_PTR(-ENOBUFS);
 383
 384	tp->ops = tcf_proto_lookup_ops(kind, rtnl_held, extack);
 385	if (IS_ERR(tp->ops)) {
 386		err = PTR_ERR(tp->ops);
 387		goto errout;
 388	}
 389	tp->classify = tp->ops->classify;
 390	tp->protocol = protocol;
 391	tp->prio = prio;
 392	tp->chain = chain;
 393	spin_lock_init(&tp->lock);
 394	refcount_set(&tp->refcnt, 1);
 395
 396	err = tp->ops->init(tp);
 397	if (err) {
 398		module_put(tp->ops->owner);
 399		goto errout;
 400	}
 401	return tp;
 402
 403errout:
 404	kfree(tp);
 405	return ERR_PTR(err);
 406}
 407
 408static void tcf_proto_get(struct tcf_proto *tp)
 409{
 410	refcount_inc(&tp->refcnt);
 411}
 412
 413static void tcf_chain_put(struct tcf_chain *chain);
 414
 415static void tcf_proto_destroy(struct tcf_proto *tp, bool rtnl_held,
 416			      bool sig_destroy, struct netlink_ext_ack *extack)
 417{
 418	tp->ops->destroy(tp, rtnl_held, extack);
 419	if (sig_destroy)
 420		tcf_proto_signal_destroyed(tp->chain, tp);
 421	tcf_chain_put(tp->chain);
 422	module_put(tp->ops->owner);
 423	kfree_rcu(tp, rcu);
 424}
 425
 426static void tcf_proto_put(struct tcf_proto *tp, bool rtnl_held,
 427			  struct netlink_ext_ack *extack)
 428{
 429	if (refcount_dec_and_test(&tp->refcnt))
 430		tcf_proto_destroy(tp, rtnl_held, true, extack);
 431}
 432
 433static bool tcf_proto_check_delete(struct tcf_proto *tp)
 
 
 
 
 
 
 
 
 
 
 434{
 435	if (tp->ops->delete_empty)
 436		return tp->ops->delete_empty(tp);
 
 
 
 
 
 
 437
 438	tp->deleting = true;
 
 
 
 
 
 439	return tp->deleting;
 440}
 441
 442static void tcf_proto_mark_delete(struct tcf_proto *tp)
 443{
 444	spin_lock(&tp->lock);
 445	tp->deleting = true;
 446	spin_unlock(&tp->lock);
 447}
 448
 449static bool tcf_proto_is_deleting(struct tcf_proto *tp)
 450{
 451	bool deleting;
 452
 453	spin_lock(&tp->lock);
 454	deleting = tp->deleting;
 455	spin_unlock(&tp->lock);
 456
 457	return deleting;
 458}
 459
 460#define ASSERT_BLOCK_LOCKED(block)					\
 461	lockdep_assert_held(&(block)->lock)
 462
 463struct tcf_filter_chain_list_item {
 464	struct list_head list;
 465	tcf_chain_head_change_t *chain_head_change;
 466	void *chain_head_change_priv;
 467};
 468
 469static struct tcf_chain *tcf_chain_create(struct tcf_block *block,
 470					  u32 chain_index)
 471{
 472	struct tcf_chain *chain;
 473
 474	ASSERT_BLOCK_LOCKED(block);
 475
 476	chain = kzalloc(sizeof(*chain), GFP_KERNEL);
 477	if (!chain)
 478		return NULL;
 479	list_add_tail_rcu(&chain->list, &block->chain_list);
 480	mutex_init(&chain->filter_chain_lock);
 481	chain->block = block;
 482	chain->index = chain_index;
 483	chain->refcnt = 1;
 484	if (!chain->index)
 485		block->chain0.chain = chain;
 486	return chain;
 487}
 488
 489static void tcf_chain_head_change_item(struct tcf_filter_chain_list_item *item,
 490				       struct tcf_proto *tp_head)
 491{
 492	if (item->chain_head_change)
 493		item->chain_head_change(tp_head, item->chain_head_change_priv);
 494}
 495
 496static void tcf_chain0_head_change(struct tcf_chain *chain,
 497				   struct tcf_proto *tp_head)
 498{
 499	struct tcf_filter_chain_list_item *item;
 500	struct tcf_block *block = chain->block;
 501
 502	if (chain->index)
 503		return;
 504
 505	mutex_lock(&block->lock);
 506	list_for_each_entry(item, &block->chain0.filter_chain_list, list)
 507		tcf_chain_head_change_item(item, tp_head);
 508	mutex_unlock(&block->lock);
 509}
 510
 511/* Returns true if block can be safely freed. */
 512
 513static bool tcf_chain_detach(struct tcf_chain *chain)
 514{
 515	struct tcf_block *block = chain->block;
 516
 517	ASSERT_BLOCK_LOCKED(block);
 518
 519	list_del_rcu(&chain->list);
 520	if (!chain->index)
 521		block->chain0.chain = NULL;
 522
 523	if (list_empty(&block->chain_list) &&
 524	    refcount_read(&block->refcnt) == 0)
 525		return true;
 526
 527	return false;
 528}
 529
 530static void tcf_block_destroy(struct tcf_block *block)
 531{
 532	mutex_destroy(&block->lock);
 533	mutex_destroy(&block->proto_destroy_lock);
 534	xa_destroy(&block->ports);
 535	kfree_rcu(block, rcu);
 536}
 537
 538static void tcf_chain_destroy(struct tcf_chain *chain, bool free_block)
 539{
 540	struct tcf_block *block = chain->block;
 541
 542	mutex_destroy(&chain->filter_chain_lock);
 543	kfree_rcu(chain, rcu);
 544	if (free_block)
 545		tcf_block_destroy(block);
 546}
 547
 548static void tcf_chain_hold(struct tcf_chain *chain)
 549{
 550	ASSERT_BLOCK_LOCKED(chain->block);
 551
 552	++chain->refcnt;
 553}
 554
 555static bool tcf_chain_held_by_acts_only(struct tcf_chain *chain)
 556{
 557	ASSERT_BLOCK_LOCKED(chain->block);
 558
 559	/* In case all the references are action references, this
 560	 * chain should not be shown to the user.
 561	 */
 562	return chain->refcnt == chain->action_refcnt;
 563}
 564
 565static struct tcf_chain *tcf_chain_lookup(struct tcf_block *block,
 566					  u32 chain_index)
 567{
 568	struct tcf_chain *chain;
 569
 570	ASSERT_BLOCK_LOCKED(block);
 571
 572	list_for_each_entry(chain, &block->chain_list, list) {
 573		if (chain->index == chain_index)
 574			return chain;
 575	}
 576	return NULL;
 577}
 578
 579#if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
 580static struct tcf_chain *tcf_chain_lookup_rcu(const struct tcf_block *block,
 581					      u32 chain_index)
 582{
 583	struct tcf_chain *chain;
 584
 585	list_for_each_entry_rcu(chain, &block->chain_list, list) {
 586		if (chain->index == chain_index)
 587			return chain;
 588	}
 589	return NULL;
 590}
 591#endif
 592
 593static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb,
 594			   u32 seq, u16 flags, int event, bool unicast,
 595			   struct netlink_ext_ack *extack);
 596
 597static struct tcf_chain *__tcf_chain_get(struct tcf_block *block,
 598					 u32 chain_index, bool create,
 599					 bool by_act)
 600{
 601	struct tcf_chain *chain = NULL;
 602	bool is_first_reference;
 603
 604	mutex_lock(&block->lock);
 605	chain = tcf_chain_lookup(block, chain_index);
 606	if (chain) {
 607		tcf_chain_hold(chain);
 608	} else {
 609		if (!create)
 610			goto errout;
 611		chain = tcf_chain_create(block, chain_index);
 612		if (!chain)
 613			goto errout;
 614	}
 615
 616	if (by_act)
 617		++chain->action_refcnt;
 618	is_first_reference = chain->refcnt - chain->action_refcnt == 1;
 619	mutex_unlock(&block->lock);
 620
 621	/* Send notification only in case we got the first
 622	 * non-action reference. Until then, the chain acts only as
 623	 * a placeholder for actions pointing to it and user ought
 624	 * not know about them.
 625	 */
 626	if (is_first_reference && !by_act)
 627		tc_chain_notify(chain, NULL, 0, NLM_F_CREATE | NLM_F_EXCL,
 628				RTM_NEWCHAIN, false, NULL);
 629
 630	return chain;
 631
 632errout:
 633	mutex_unlock(&block->lock);
 634	return chain;
 635}
 636
 637static struct tcf_chain *tcf_chain_get(struct tcf_block *block, u32 chain_index,
 638				       bool create)
 639{
 640	return __tcf_chain_get(block, chain_index, create, false);
 641}
 642
 643struct tcf_chain *tcf_chain_get_by_act(struct tcf_block *block, u32 chain_index)
 644{
 645	return __tcf_chain_get(block, chain_index, true, true);
 646}
 647EXPORT_SYMBOL(tcf_chain_get_by_act);
 648
 649static void tc_chain_tmplt_del(const struct tcf_proto_ops *tmplt_ops,
 650			       void *tmplt_priv);
 651static int tc_chain_notify_delete(const struct tcf_proto_ops *tmplt_ops,
 652				  void *tmplt_priv, u32 chain_index,
 653				  struct tcf_block *block, struct sk_buff *oskb,
 654				  u32 seq, u16 flags);
 655
 656static void __tcf_chain_put(struct tcf_chain *chain, bool by_act,
 657			    bool explicitly_created)
 658{
 659	struct tcf_block *block = chain->block;
 660	const struct tcf_proto_ops *tmplt_ops;
 661	unsigned int refcnt, non_act_refcnt;
 662	bool free_block = false;
 
 663	void *tmplt_priv;
 664
 665	mutex_lock(&block->lock);
 666	if (explicitly_created) {
 667		if (!chain->explicitly_created) {
 668			mutex_unlock(&block->lock);
 669			return;
 670		}
 671		chain->explicitly_created = false;
 672	}
 673
 674	if (by_act)
 675		chain->action_refcnt--;
 676
 677	/* tc_chain_notify_delete can't be called while holding block lock.
 678	 * However, when block is unlocked chain can be changed concurrently, so
 679	 * save these to temporary variables.
 680	 */
 681	refcnt = --chain->refcnt;
 682	non_act_refcnt = refcnt - chain->action_refcnt;
 683	tmplt_ops = chain->tmplt_ops;
 684	tmplt_priv = chain->tmplt_priv;
 685
 686	if (non_act_refcnt == chain->explicitly_created && !by_act) {
 687		if (non_act_refcnt == 0)
 688			tc_chain_notify_delete(tmplt_ops, tmplt_priv,
 689					       chain->index, block, NULL, 0, 0);
 690		/* Last reference to chain, no need to lock. */
 691		chain->flushing = false;
 692	}
 693
 694	if (refcnt == 0)
 695		free_block = tcf_chain_detach(chain);
 696	mutex_unlock(&block->lock);
 697
 698	if (refcnt == 0) {
 699		tc_chain_tmplt_del(tmplt_ops, tmplt_priv);
 700		tcf_chain_destroy(chain, free_block);
 701	}
 702}
 703
 704static void tcf_chain_put(struct tcf_chain *chain)
 705{
 706	__tcf_chain_put(chain, false, false);
 707}
 708
 709void tcf_chain_put_by_act(struct tcf_chain *chain)
 710{
 711	__tcf_chain_put(chain, true, false);
 712}
 713EXPORT_SYMBOL(tcf_chain_put_by_act);
 714
 715static void tcf_chain_put_explicitly_created(struct tcf_chain *chain)
 716{
 717	__tcf_chain_put(chain, false, true);
 718}
 719
 720static void tcf_chain_flush(struct tcf_chain *chain, bool rtnl_held)
 721{
 722	struct tcf_proto *tp, *tp_next;
 723
 724	mutex_lock(&chain->filter_chain_lock);
 725	tp = tcf_chain_dereference(chain->filter_chain, chain);
 726	while (tp) {
 727		tp_next = rcu_dereference_protected(tp->next, 1);
 728		tcf_proto_signal_destroying(chain, tp);
 729		tp = tp_next;
 730	}
 731	tp = tcf_chain_dereference(chain->filter_chain, chain);
 732	RCU_INIT_POINTER(chain->filter_chain, NULL);
 733	tcf_chain0_head_change(chain, NULL);
 734	chain->flushing = true;
 735	mutex_unlock(&chain->filter_chain_lock);
 736
 737	while (tp) {
 738		tp_next = rcu_dereference_protected(tp->next, 1);
 739		tcf_proto_put(tp, rtnl_held, NULL);
 740		tp = tp_next;
 741	}
 742}
 743
 744static int tcf_block_setup(struct tcf_block *block,
 745			   struct flow_block_offload *bo);
 746
 747static void tcf_block_offload_init(struct flow_block_offload *bo,
 748				   struct net_device *dev, struct Qdisc *sch,
 749				   enum flow_block_command command,
 750				   enum flow_block_binder_type binder_type,
 751				   struct flow_block *flow_block,
 752				   bool shared, struct netlink_ext_ack *extack)
 753{
 754	bo->net = dev_net(dev);
 755	bo->command = command;
 756	bo->binder_type = binder_type;
 757	bo->block = flow_block;
 758	bo->block_shared = shared;
 759	bo->extack = extack;
 760	bo->sch = sch;
 761	bo->cb_list_head = &flow_block->cb_list;
 762	INIT_LIST_HEAD(&bo->cb_list);
 
 
 
 
 
 
 
 
 763}
 764
 765static void tcf_block_unbind(struct tcf_block *block,
 766			     struct flow_block_offload *bo);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 767
 768static void tc_block_indr_cleanup(struct flow_block_cb *block_cb)
 
 
 
 
 769{
 770	struct tcf_block *block = block_cb->indr.data;
 771	struct net_device *dev = block_cb->indr.dev;
 772	struct Qdisc *sch = block_cb->indr.sch;
 773	struct netlink_ext_ack extack = {};
 774	struct flow_block_offload bo = {};
 
 
 
 
 775
 776	tcf_block_offload_init(&bo, dev, sch, FLOW_BLOCK_UNBIND,
 777			       block_cb->indr.binder_type,
 778			       &block->flow_block, tcf_block_shared(block),
 779			       &extack);
 780	rtnl_lock();
 781	down_write(&block->cb_lock);
 782	list_del(&block_cb->driver_list);
 783	list_move(&block_cb->list, &bo.cb_list);
 784	tcf_block_unbind(block, &bo);
 785	up_write(&block->cb_lock);
 786	rtnl_unlock();
 787}
 788
 789static bool tcf_block_offload_in_use(struct tcf_block *block)
 790{
 791	return atomic_read(&block->offloadcnt);
 792}
 793
 794static int tcf_block_offload_cmd(struct tcf_block *block,
 795				 struct net_device *dev, struct Qdisc *sch,
 796				 struct tcf_block_ext_info *ei,
 797				 enum flow_block_command command,
 798				 struct netlink_ext_ack *extack)
 799{
 800	struct flow_block_offload bo = {};
 
 801
 802	tcf_block_offload_init(&bo, dev, sch, command, ei->binder_type,
 803			       &block->flow_block, tcf_block_shared(block),
 804			       extack);
 
 
 
 
 805
 806	if (dev->netdev_ops->ndo_setup_tc) {
 807		int err;
 808
 809		err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_BLOCK, &bo);
 810		if (err < 0) {
 811			if (err != -EOPNOTSUPP)
 812				NL_SET_ERR_MSG(extack, "Driver ndo_setup_tc failed");
 813			return err;
 814		}
 815
 816		return tcf_block_setup(block, &bo);
 817	}
 818
 819	flow_indr_dev_setup_offload(dev, sch, TC_SETUP_BLOCK, block, &bo,
 820				    tc_block_indr_cleanup);
 821	tcf_block_setup(block, &bo);
 822
 823	return -EOPNOTSUPP;
 824}
 825
 826static int tcf_block_offload_bind(struct tcf_block *block, struct Qdisc *q,
 827				  struct tcf_block_ext_info *ei,
 828				  struct netlink_ext_ack *extack)
 829{
 830	struct net_device *dev = q->dev_queue->dev;
 831	int err;
 832
 833	down_write(&block->cb_lock);
 
 
 834
 835	/* If tc offload feature is disabled and the block we try to bind
 836	 * to already has some offloaded filters, forbid to bind.
 837	 */
 838	if (dev->netdev_ops->ndo_setup_tc &&
 839	    !tc_can_offload(dev) &&
 840	    tcf_block_offload_in_use(block)) {
 841		NL_SET_ERR_MSG(extack, "Bind to offloaded block failed as dev has offload disabled");
 842		err = -EOPNOTSUPP;
 843		goto err_unlock;
 844	}
 845
 846	err = tcf_block_offload_cmd(block, dev, q, ei, FLOW_BLOCK_BIND, extack);
 847	if (err == -EOPNOTSUPP)
 848		goto no_offload_dev_inc;
 849	if (err)
 850		goto err_unlock;
 851
 
 852	up_write(&block->cb_lock);
 853	return 0;
 854
 855no_offload_dev_inc:
 856	if (tcf_block_offload_in_use(block))
 
 857		goto err_unlock;
 858
 859	err = 0;
 860	block->nooffloaddevcnt++;
 
 861err_unlock:
 862	up_write(&block->cb_lock);
 863	return err;
 864}
 865
 866static void tcf_block_offload_unbind(struct tcf_block *block, struct Qdisc *q,
 867				     struct tcf_block_ext_info *ei)
 868{
 869	struct net_device *dev = q->dev_queue->dev;
 870	int err;
 871
 872	down_write(&block->cb_lock);
 873	err = tcf_block_offload_cmd(block, dev, q, ei, FLOW_BLOCK_UNBIND, NULL);
 
 
 
 
 874	if (err == -EOPNOTSUPP)
 875		goto no_offload_dev_dec;
 876	up_write(&block->cb_lock);
 877	return;
 878
 879no_offload_dev_dec:
 880	WARN_ON(block->nooffloaddevcnt-- == 0);
 881	up_write(&block->cb_lock);
 882}
 883
 884static int
 885tcf_chain0_head_change_cb_add(struct tcf_block *block,
 886			      struct tcf_block_ext_info *ei,
 887			      struct netlink_ext_ack *extack)
 888{
 889	struct tcf_filter_chain_list_item *item;
 890	struct tcf_chain *chain0;
 891
 892	item = kmalloc(sizeof(*item), GFP_KERNEL);
 893	if (!item) {
 894		NL_SET_ERR_MSG(extack, "Memory allocation for head change callback item failed");
 895		return -ENOMEM;
 896	}
 897	item->chain_head_change = ei->chain_head_change;
 898	item->chain_head_change_priv = ei->chain_head_change_priv;
 899
 900	mutex_lock(&block->lock);
 901	chain0 = block->chain0.chain;
 902	if (chain0)
 903		tcf_chain_hold(chain0);
 904	else
 905		list_add(&item->list, &block->chain0.filter_chain_list);
 906	mutex_unlock(&block->lock);
 907
 908	if (chain0) {
 909		struct tcf_proto *tp_head;
 910
 911		mutex_lock(&chain0->filter_chain_lock);
 912
 913		tp_head = tcf_chain_dereference(chain0->filter_chain, chain0);
 914		if (tp_head)
 915			tcf_chain_head_change_item(item, tp_head);
 916
 917		mutex_lock(&block->lock);
 918		list_add(&item->list, &block->chain0.filter_chain_list);
 919		mutex_unlock(&block->lock);
 920
 921		mutex_unlock(&chain0->filter_chain_lock);
 922		tcf_chain_put(chain0);
 923	}
 924
 925	return 0;
 926}
 927
 928static void
 929tcf_chain0_head_change_cb_del(struct tcf_block *block,
 930			      struct tcf_block_ext_info *ei)
 931{
 932	struct tcf_filter_chain_list_item *item;
 933
 934	mutex_lock(&block->lock);
 935	list_for_each_entry(item, &block->chain0.filter_chain_list, list) {
 936		if ((!ei->chain_head_change && !ei->chain_head_change_priv) ||
 937		    (item->chain_head_change == ei->chain_head_change &&
 938		     item->chain_head_change_priv == ei->chain_head_change_priv)) {
 939			if (block->chain0.chain)
 940				tcf_chain_head_change_item(item, NULL);
 941			list_del(&item->list);
 942			mutex_unlock(&block->lock);
 943
 944			kfree(item);
 945			return;
 946		}
 947	}
 948	mutex_unlock(&block->lock);
 949	WARN_ON(1);
 950}
 951
 952struct tcf_net {
 953	spinlock_t idr_lock; /* Protects idr */
 954	struct idr idr;
 955};
 956
 957static unsigned int tcf_net_id;
 958
 959static int tcf_block_insert(struct tcf_block *block, struct net *net,
 960			    struct netlink_ext_ack *extack)
 961{
 962	struct tcf_net *tn = net_generic(net, tcf_net_id);
 963	int err;
 964
 965	idr_preload(GFP_KERNEL);
 966	spin_lock(&tn->idr_lock);
 967	err = idr_alloc_u32(&tn->idr, block, &block->index, block->index,
 968			    GFP_NOWAIT);
 969	spin_unlock(&tn->idr_lock);
 970	idr_preload_end();
 971
 972	return err;
 973}
 974
 975static void tcf_block_remove(struct tcf_block *block, struct net *net)
 976{
 977	struct tcf_net *tn = net_generic(net, tcf_net_id);
 978
 979	spin_lock(&tn->idr_lock);
 980	idr_remove(&tn->idr, block->index);
 981	spin_unlock(&tn->idr_lock);
 982}
 983
 984static struct tcf_block *tcf_block_create(struct net *net, struct Qdisc *q,
 985					  u32 block_index,
 986					  struct netlink_ext_ack *extack)
 987{
 988	struct tcf_block *block;
 989
 990	block = kzalloc(sizeof(*block), GFP_KERNEL);
 991	if (!block) {
 992		NL_SET_ERR_MSG(extack, "Memory allocation for block failed");
 993		return ERR_PTR(-ENOMEM);
 994	}
 995	mutex_init(&block->lock);
 996	mutex_init(&block->proto_destroy_lock);
 997	init_rwsem(&block->cb_lock);
 998	flow_block_init(&block->flow_block);
 999	INIT_LIST_HEAD(&block->chain_list);
1000	INIT_LIST_HEAD(&block->owner_list);
1001	INIT_LIST_HEAD(&block->chain0.filter_chain_list);
1002
1003	refcount_set(&block->refcnt, 1);
1004	block->net = net;
1005	block->index = block_index;
1006	xa_init(&block->ports);
1007
1008	/* Don't store q pointer for blocks which are shared */
1009	if (!tcf_block_shared(block))
1010		block->q = q;
1011	return block;
1012}
1013
1014struct tcf_block *tcf_block_lookup(struct net *net, u32 block_index)
1015{
1016	struct tcf_net *tn = net_generic(net, tcf_net_id);
1017
1018	return idr_find(&tn->idr, block_index);
1019}
1020EXPORT_SYMBOL(tcf_block_lookup);
1021
1022static struct tcf_block *tcf_block_refcnt_get(struct net *net, u32 block_index)
1023{
1024	struct tcf_block *block;
1025
1026	rcu_read_lock();
1027	block = tcf_block_lookup(net, block_index);
1028	if (block && !refcount_inc_not_zero(&block->refcnt))
1029		block = NULL;
1030	rcu_read_unlock();
1031
1032	return block;
1033}
1034
1035static struct tcf_chain *
1036__tcf_get_next_chain(struct tcf_block *block, struct tcf_chain *chain)
1037{
1038	mutex_lock(&block->lock);
1039	if (chain)
1040		chain = list_is_last(&chain->list, &block->chain_list) ?
1041			NULL : list_next_entry(chain, list);
1042	else
1043		chain = list_first_entry_or_null(&block->chain_list,
1044						 struct tcf_chain, list);
1045
1046	/* skip all action-only chains */
1047	while (chain && tcf_chain_held_by_acts_only(chain))
1048		chain = list_is_last(&chain->list, &block->chain_list) ?
1049			NULL : list_next_entry(chain, list);
1050
1051	if (chain)
1052		tcf_chain_hold(chain);
1053	mutex_unlock(&block->lock);
1054
1055	return chain;
1056}
1057
1058/* Function to be used by all clients that want to iterate over all chains on
1059 * block. It properly obtains block->lock and takes reference to chain before
1060 * returning it. Users of this function must be tolerant to concurrent chain
1061 * insertion/deletion or ensure that no concurrent chain modification is
1062 * possible. Note that all netlink dump callbacks cannot guarantee to provide
1063 * consistent dump because rtnl lock is released each time skb is filled with
1064 * data and sent to user-space.
1065 */
1066
1067struct tcf_chain *
1068tcf_get_next_chain(struct tcf_block *block, struct tcf_chain *chain)
1069{
1070	struct tcf_chain *chain_next = __tcf_get_next_chain(block, chain);
1071
1072	if (chain)
1073		tcf_chain_put(chain);
1074
1075	return chain_next;
1076}
1077EXPORT_SYMBOL(tcf_get_next_chain);
1078
1079static struct tcf_proto *
1080__tcf_get_next_proto(struct tcf_chain *chain, struct tcf_proto *tp)
1081{
1082	u32 prio = 0;
1083
1084	ASSERT_RTNL();
1085	mutex_lock(&chain->filter_chain_lock);
1086
1087	if (!tp) {
1088		tp = tcf_chain_dereference(chain->filter_chain, chain);
1089	} else if (tcf_proto_is_deleting(tp)) {
1090		/* 'deleting' flag is set and chain->filter_chain_lock was
1091		 * unlocked, which means next pointer could be invalid. Restart
1092		 * search.
1093		 */
1094		prio = tp->prio + 1;
1095		tp = tcf_chain_dereference(chain->filter_chain, chain);
1096
1097		for (; tp; tp = tcf_chain_dereference(tp->next, chain))
1098			if (!tp->deleting && tp->prio >= prio)
1099				break;
1100	} else {
1101		tp = tcf_chain_dereference(tp->next, chain);
1102	}
1103
1104	if (tp)
1105		tcf_proto_get(tp);
1106
1107	mutex_unlock(&chain->filter_chain_lock);
1108
1109	return tp;
1110}
1111
1112/* Function to be used by all clients that want to iterate over all tp's on
1113 * chain. Users of this function must be tolerant to concurrent tp
1114 * insertion/deletion or ensure that no concurrent chain modification is
1115 * possible. Note that all netlink dump callbacks cannot guarantee to provide
1116 * consistent dump because rtnl lock is released each time skb is filled with
1117 * data and sent to user-space.
1118 */
1119
1120struct tcf_proto *
1121tcf_get_next_proto(struct tcf_chain *chain, struct tcf_proto *tp)
 
1122{
1123	struct tcf_proto *tp_next = __tcf_get_next_proto(chain, tp);
1124
1125	if (tp)
1126		tcf_proto_put(tp, true, NULL);
1127
1128	return tp_next;
1129}
1130EXPORT_SYMBOL(tcf_get_next_proto);
1131
1132static void tcf_block_flush_all_chains(struct tcf_block *block, bool rtnl_held)
1133{
1134	struct tcf_chain *chain;
1135
1136	/* Last reference to block. At this point chains cannot be added or
1137	 * removed concurrently.
1138	 */
1139	for (chain = tcf_get_next_chain(block, NULL);
1140	     chain;
1141	     chain = tcf_get_next_chain(block, chain)) {
1142		tcf_chain_put_explicitly_created(chain);
1143		tcf_chain_flush(chain, rtnl_held);
1144	}
1145}
1146
1147/* Lookup Qdisc and increments its reference counter.
1148 * Set parent, if necessary.
1149 */
1150
1151static int __tcf_qdisc_find(struct net *net, struct Qdisc **q,
1152			    u32 *parent, int ifindex, bool rtnl_held,
1153			    struct netlink_ext_ack *extack)
1154{
1155	const struct Qdisc_class_ops *cops;
1156	struct net_device *dev;
1157	int err = 0;
1158
1159	if (ifindex == TCM_IFINDEX_MAGIC_BLOCK)
1160		return 0;
1161
1162	rcu_read_lock();
1163
1164	/* Find link */
1165	dev = dev_get_by_index_rcu(net, ifindex);
1166	if (!dev) {
1167		rcu_read_unlock();
1168		return -ENODEV;
1169	}
1170
1171	/* Find qdisc */
1172	if (!*parent) {
1173		*q = rcu_dereference(dev->qdisc);
1174		*parent = (*q)->handle;
1175	} else {
1176		*q = qdisc_lookup_rcu(dev, TC_H_MAJ(*parent));
1177		if (!*q) {
1178			NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists");
1179			err = -EINVAL;
1180			goto errout_rcu;
1181		}
1182	}
1183
1184	*q = qdisc_refcount_inc_nz(*q);
1185	if (!*q) {
1186		NL_SET_ERR_MSG(extack, "Parent Qdisc doesn't exists");
1187		err = -EINVAL;
1188		goto errout_rcu;
1189	}
1190
1191	/* Is it classful? */
1192	cops = (*q)->ops->cl_ops;
1193	if (!cops) {
1194		NL_SET_ERR_MSG(extack, "Qdisc not classful");
1195		err = -EINVAL;
1196		goto errout_qdisc;
1197	}
1198
1199	if (!cops->tcf_block) {
1200		NL_SET_ERR_MSG(extack, "Class doesn't support blocks");
1201		err = -EOPNOTSUPP;
1202		goto errout_qdisc;
1203	}
1204
1205errout_rcu:
1206	/* At this point we know that qdisc is not noop_qdisc,
1207	 * which means that qdisc holds a reference to net_device
1208	 * and we hold a reference to qdisc, so it is safe to release
1209	 * rcu read lock.
1210	 */
1211	rcu_read_unlock();
1212	return err;
1213
1214errout_qdisc:
1215	rcu_read_unlock();
1216
1217	if (rtnl_held)
1218		qdisc_put(*q);
1219	else
1220		qdisc_put_unlocked(*q);
1221	*q = NULL;
1222
1223	return err;
1224}
1225
1226static int __tcf_qdisc_cl_find(struct Qdisc *q, u32 parent, unsigned long *cl,
1227			       int ifindex, struct netlink_ext_ack *extack)
1228{
1229	if (ifindex == TCM_IFINDEX_MAGIC_BLOCK)
1230		return 0;
1231
1232	/* Do we search for filter, attached to class? */
1233	if (TC_H_MIN(parent)) {
1234		const struct Qdisc_class_ops *cops = q->ops->cl_ops;
1235
1236		*cl = cops->find(q, parent);
1237		if (*cl == 0) {
1238			NL_SET_ERR_MSG(extack, "Specified class doesn't exist");
1239			return -ENOENT;
1240		}
1241	}
1242
1243	return 0;
1244}
1245
1246static struct tcf_block *__tcf_block_find(struct net *net, struct Qdisc *q,
1247					  unsigned long cl, int ifindex,
1248					  u32 block_index,
1249					  struct netlink_ext_ack *extack)
1250{
1251	struct tcf_block *block;
1252
1253	if (ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
1254		block = tcf_block_refcnt_get(net, block_index);
1255		if (!block) {
1256			NL_SET_ERR_MSG(extack, "Block of given index was not found");
1257			return ERR_PTR(-EINVAL);
1258		}
1259	} else {
1260		const struct Qdisc_class_ops *cops = q->ops->cl_ops;
1261
1262		block = cops->tcf_block(q, cl, extack);
1263		if (!block)
1264			return ERR_PTR(-EINVAL);
1265
1266		if (tcf_block_shared(block)) {
1267			NL_SET_ERR_MSG(extack, "This filter block is shared. Please use the block index to manipulate the filters");
1268			return ERR_PTR(-EOPNOTSUPP);
1269		}
1270
1271		/* Always take reference to block in order to support execution
1272		 * of rules update path of cls API without rtnl lock. Caller
1273		 * must release block when it is finished using it. 'if' block
1274		 * of this conditional obtain reference to block by calling
1275		 * tcf_block_refcnt_get().
1276		 */
1277		refcount_inc(&block->refcnt);
1278	}
1279
1280	return block;
1281}
1282
1283static void __tcf_block_put(struct tcf_block *block, struct Qdisc *q,
1284			    struct tcf_block_ext_info *ei, bool rtnl_held)
1285{
1286	if (refcount_dec_and_mutex_lock(&block->refcnt, &block->lock)) {
1287		/* Flushing/putting all chains will cause the block to be
1288		 * deallocated when last chain is freed. However, if chain_list
1289		 * is empty, block has to be manually deallocated. After block
1290		 * reference counter reached 0, it is no longer possible to
1291		 * increment it or add new chains to block.
1292		 */
1293		bool free_block = list_empty(&block->chain_list);
1294
1295		mutex_unlock(&block->lock);
1296		if (tcf_block_shared(block))
1297			tcf_block_remove(block, block->net);
1298
1299		if (q)
1300			tcf_block_offload_unbind(block, q, ei);
1301
1302		if (free_block)
1303			tcf_block_destroy(block);
1304		else
1305			tcf_block_flush_all_chains(block, rtnl_held);
1306	} else if (q) {
1307		tcf_block_offload_unbind(block, q, ei);
1308	}
1309}
1310
1311static void tcf_block_refcnt_put(struct tcf_block *block, bool rtnl_held)
1312{
1313	__tcf_block_put(block, NULL, NULL, rtnl_held);
1314}
1315
1316/* Find tcf block.
1317 * Set q, parent, cl when appropriate.
1318 */
1319
1320static struct tcf_block *tcf_block_find(struct net *net, struct Qdisc **q,
1321					u32 *parent, unsigned long *cl,
1322					int ifindex, u32 block_index,
1323					struct netlink_ext_ack *extack)
1324{
1325	struct tcf_block *block;
1326	int err = 0;
1327
1328	ASSERT_RTNL();
1329
1330	err = __tcf_qdisc_find(net, q, parent, ifindex, true, extack);
1331	if (err)
1332		goto errout;
1333
1334	err = __tcf_qdisc_cl_find(*q, *parent, cl, ifindex, extack);
1335	if (err)
1336		goto errout_qdisc;
1337
1338	block = __tcf_block_find(net, *q, *cl, ifindex, block_index, extack);
1339	if (IS_ERR(block)) {
1340		err = PTR_ERR(block);
1341		goto errout_qdisc;
1342	}
1343
1344	return block;
1345
1346errout_qdisc:
1347	if (*q)
1348		qdisc_put(*q);
1349errout:
1350	*q = NULL;
1351	return ERR_PTR(err);
1352}
1353
1354static void tcf_block_release(struct Qdisc *q, struct tcf_block *block,
1355			      bool rtnl_held)
1356{
1357	if (!IS_ERR_OR_NULL(block))
1358		tcf_block_refcnt_put(block, rtnl_held);
1359
1360	if (q) {
1361		if (rtnl_held)
1362			qdisc_put(q);
1363		else
1364			qdisc_put_unlocked(q);
1365	}
1366}
1367
1368struct tcf_block_owner_item {
1369	struct list_head list;
1370	struct Qdisc *q;
1371	enum flow_block_binder_type binder_type;
1372};
1373
1374static void
1375tcf_block_owner_netif_keep_dst(struct tcf_block *block,
1376			       struct Qdisc *q,
1377			       enum flow_block_binder_type binder_type)
1378{
1379	if (block->keep_dst &&
1380	    binder_type != FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS &&
1381	    binder_type != FLOW_BLOCK_BINDER_TYPE_CLSACT_EGRESS)
1382		netif_keep_dst(qdisc_dev(q));
1383}
1384
1385void tcf_block_netif_keep_dst(struct tcf_block *block)
1386{
1387	struct tcf_block_owner_item *item;
1388
1389	block->keep_dst = true;
1390	list_for_each_entry(item, &block->owner_list, list)
1391		tcf_block_owner_netif_keep_dst(block, item->q,
1392					       item->binder_type);
1393}
1394EXPORT_SYMBOL(tcf_block_netif_keep_dst);
1395
1396static int tcf_block_owner_add(struct tcf_block *block,
1397			       struct Qdisc *q,
1398			       enum flow_block_binder_type binder_type)
1399{
1400	struct tcf_block_owner_item *item;
1401
1402	item = kmalloc(sizeof(*item), GFP_KERNEL);
1403	if (!item)
1404		return -ENOMEM;
1405	item->q = q;
1406	item->binder_type = binder_type;
1407	list_add(&item->list, &block->owner_list);
1408	return 0;
1409}
1410
1411static void tcf_block_owner_del(struct tcf_block *block,
1412				struct Qdisc *q,
1413				enum flow_block_binder_type binder_type)
1414{
1415	struct tcf_block_owner_item *item;
1416
1417	list_for_each_entry(item, &block->owner_list, list) {
1418		if (item->q == q && item->binder_type == binder_type) {
1419			list_del(&item->list);
1420			kfree(item);
1421			return;
1422		}
1423	}
1424	WARN_ON(1);
1425}
1426
1427static bool tcf_block_tracks_dev(struct tcf_block *block,
1428				 struct tcf_block_ext_info *ei)
1429{
1430	return tcf_block_shared(block) &&
1431	       (ei->binder_type == FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS ||
1432		ei->binder_type == FLOW_BLOCK_BINDER_TYPE_CLSACT_EGRESS);
1433}
1434
1435int tcf_block_get_ext(struct tcf_block **p_block, struct Qdisc *q,
1436		      struct tcf_block_ext_info *ei,
1437		      struct netlink_ext_ack *extack)
1438{
1439	struct net_device *dev = qdisc_dev(q);
1440	struct net *net = qdisc_net(q);
1441	struct tcf_block *block = NULL;
1442	int err;
1443
1444	if (ei->block_index)
1445		/* block_index not 0 means the shared block is requested */
1446		block = tcf_block_refcnt_get(net, ei->block_index);
1447
1448	if (!block) {
1449		block = tcf_block_create(net, q, ei->block_index, extack);
1450		if (IS_ERR(block))
1451			return PTR_ERR(block);
1452		if (tcf_block_shared(block)) {
1453			err = tcf_block_insert(block, net, extack);
1454			if (err)
1455				goto err_block_insert;
1456		}
1457	}
1458
1459	err = tcf_block_owner_add(block, q, ei->binder_type);
1460	if (err)
1461		goto err_block_owner_add;
1462
1463	tcf_block_owner_netif_keep_dst(block, q, ei->binder_type);
1464
1465	err = tcf_chain0_head_change_cb_add(block, ei, extack);
1466	if (err)
1467		goto err_chain0_head_change_cb_add;
1468
1469	err = tcf_block_offload_bind(block, q, ei, extack);
1470	if (err)
1471		goto err_block_offload_bind;
1472
1473	if (tcf_block_tracks_dev(block, ei)) {
1474		err = xa_insert(&block->ports, dev->ifindex, dev, GFP_KERNEL);
1475		if (err) {
1476			NL_SET_ERR_MSG(extack, "block dev insert failed");
1477			goto err_dev_insert;
1478		}
1479	}
1480
1481	*p_block = block;
1482	return 0;
1483
1484err_dev_insert:
1485err_block_offload_bind:
1486	tcf_chain0_head_change_cb_del(block, ei);
1487err_chain0_head_change_cb_add:
1488	tcf_block_owner_del(block, q, ei->binder_type);
1489err_block_owner_add:
1490err_block_insert:
1491	tcf_block_refcnt_put(block, true);
1492	return err;
1493}
1494EXPORT_SYMBOL(tcf_block_get_ext);
1495
1496static void tcf_chain_head_change_dflt(struct tcf_proto *tp_head, void *priv)
1497{
1498	struct tcf_proto __rcu **p_filter_chain = priv;
1499
1500	rcu_assign_pointer(*p_filter_chain, tp_head);
1501}
1502
1503int tcf_block_get(struct tcf_block **p_block,
1504		  struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q,
1505		  struct netlink_ext_ack *extack)
1506{
1507	struct tcf_block_ext_info ei = {
1508		.chain_head_change = tcf_chain_head_change_dflt,
1509		.chain_head_change_priv = p_filter_chain,
1510	};
1511
1512	WARN_ON(!p_filter_chain);
1513	return tcf_block_get_ext(p_block, q, &ei, extack);
1514}
1515EXPORT_SYMBOL(tcf_block_get);
1516
1517/* XXX: Standalone actions are not allowed to jump to any chain, and bound
1518 * actions should be all removed after flushing.
1519 */
1520void tcf_block_put_ext(struct tcf_block *block, struct Qdisc *q,
1521		       struct tcf_block_ext_info *ei)
1522{
1523	struct net_device *dev = qdisc_dev(q);
1524
1525	if (!block)
1526		return;
1527	if (tcf_block_tracks_dev(block, ei))
1528		xa_erase(&block->ports, dev->ifindex);
1529	tcf_chain0_head_change_cb_del(block, ei);
1530	tcf_block_owner_del(block, q, ei->binder_type);
1531
1532	__tcf_block_put(block, q, ei, true);
1533}
1534EXPORT_SYMBOL(tcf_block_put_ext);
1535
1536void tcf_block_put(struct tcf_block *block)
1537{
1538	struct tcf_block_ext_info ei = {0, };
1539
1540	if (!block)
1541		return;
1542	tcf_block_put_ext(block, block->q, &ei);
1543}
1544
1545EXPORT_SYMBOL(tcf_block_put);
1546
1547static int
1548tcf_block_playback_offloads(struct tcf_block *block, flow_setup_cb_t *cb,
1549			    void *cb_priv, bool add, bool offload_in_use,
1550			    struct netlink_ext_ack *extack)
1551{
1552	struct tcf_chain *chain, *chain_prev;
1553	struct tcf_proto *tp, *tp_prev;
1554	int err;
1555
1556	lockdep_assert_held(&block->cb_lock);
1557
1558	for (chain = __tcf_get_next_chain(block, NULL);
1559	     chain;
1560	     chain_prev = chain,
1561		     chain = __tcf_get_next_chain(block, chain),
1562		     tcf_chain_put(chain_prev)) {
1563		if (chain->tmplt_ops && add)
1564			chain->tmplt_ops->tmplt_reoffload(chain, true, cb,
1565							  cb_priv);
1566		for (tp = __tcf_get_next_proto(chain, NULL); tp;
1567		     tp_prev = tp,
1568			     tp = __tcf_get_next_proto(chain, tp),
1569			     tcf_proto_put(tp_prev, true, NULL)) {
1570			if (tp->ops->reoffload) {
1571				err = tp->ops->reoffload(tp, add, cb, cb_priv,
1572							 extack);
1573				if (err && add)
1574					goto err_playback_remove;
1575			} else if (add && offload_in_use) {
1576				err = -EOPNOTSUPP;
1577				NL_SET_ERR_MSG(extack, "Filter HW offload failed - classifier without re-offloading support");
1578				goto err_playback_remove;
1579			}
1580		}
1581		if (chain->tmplt_ops && !add)
1582			chain->tmplt_ops->tmplt_reoffload(chain, false, cb,
1583							  cb_priv);
1584	}
1585
1586	return 0;
1587
1588err_playback_remove:
1589	tcf_proto_put(tp, true, NULL);
1590	tcf_chain_put(chain);
1591	tcf_block_playback_offloads(block, cb, cb_priv, false, offload_in_use,
1592				    extack);
1593	return err;
1594}
1595
1596static int tcf_block_bind(struct tcf_block *block,
1597			  struct flow_block_offload *bo)
1598{
1599	struct flow_block_cb *block_cb, *next;
1600	int err, i = 0;
1601
1602	lockdep_assert_held(&block->cb_lock);
1603
1604	list_for_each_entry(block_cb, &bo->cb_list, list) {
1605		err = tcf_block_playback_offloads(block, block_cb->cb,
1606						  block_cb->cb_priv, true,
1607						  tcf_block_offload_in_use(block),
1608						  bo->extack);
1609		if (err)
1610			goto err_unroll;
1611		if (!bo->unlocked_driver_cb)
1612			block->lockeddevcnt++;
1613
1614		i++;
1615	}
1616	list_splice(&bo->cb_list, &block->flow_block.cb_list);
1617
1618	return 0;
1619
1620err_unroll:
1621	list_for_each_entry_safe(block_cb, next, &bo->cb_list, list) {
1622		list_del(&block_cb->driver_list);
1623		if (i-- > 0) {
1624			list_del(&block_cb->list);
1625			tcf_block_playback_offloads(block, block_cb->cb,
1626						    block_cb->cb_priv, false,
1627						    tcf_block_offload_in_use(block),
1628						    NULL);
1629			if (!bo->unlocked_driver_cb)
1630				block->lockeddevcnt--;
1631		}
1632		flow_block_cb_free(block_cb);
1633	}
1634
1635	return err;
1636}
1637
1638static void tcf_block_unbind(struct tcf_block *block,
1639			     struct flow_block_offload *bo)
1640{
1641	struct flow_block_cb *block_cb, *next;
1642
1643	lockdep_assert_held(&block->cb_lock);
1644
1645	list_for_each_entry_safe(block_cb, next, &bo->cb_list, list) {
1646		tcf_block_playback_offloads(block, block_cb->cb,
1647					    block_cb->cb_priv, false,
1648					    tcf_block_offload_in_use(block),
1649					    NULL);
1650		list_del(&block_cb->list);
1651		flow_block_cb_free(block_cb);
1652		if (!bo->unlocked_driver_cb)
1653			block->lockeddevcnt--;
1654	}
1655}
1656
1657static int tcf_block_setup(struct tcf_block *block,
1658			   struct flow_block_offload *bo)
1659{
1660	int err;
1661
1662	switch (bo->command) {
1663	case FLOW_BLOCK_BIND:
1664		err = tcf_block_bind(block, bo);
1665		break;
1666	case FLOW_BLOCK_UNBIND:
1667		err = 0;
1668		tcf_block_unbind(block, bo);
1669		break;
1670	default:
1671		WARN_ON_ONCE(1);
1672		err = -EOPNOTSUPP;
1673	}
1674
1675	return err;
1676}
1677
1678/* Main classifier routine: scans classifier chain attached
1679 * to this qdisc, (optionally) tests for protocol and asks
1680 * specific classifiers.
1681 */
1682static inline int __tcf_classify(struct sk_buff *skb,
1683				 const struct tcf_proto *tp,
1684				 const struct tcf_proto *orig_tp,
1685				 struct tcf_result *res,
1686				 bool compat_mode,
1687				 struct tcf_exts_miss_cookie_node *n,
1688				 int act_index,
1689				 u32 *last_executed_chain)
1690{
1691#ifdef CONFIG_NET_CLS_ACT
1692	const int max_reclassify_loop = 16;
 
1693	const struct tcf_proto *first_tp;
1694	int limit = 0;
1695
1696reclassify:
1697#endif
1698	for (; tp; tp = rcu_dereference_bh(tp->next)) {
1699		__be16 protocol = skb_protocol(skb, false);
1700		int err = 0;
1701
1702		if (n) {
1703			struct tcf_exts *exts;
1704
1705			if (n->tp_prio != tp->prio)
1706				continue;
1707
1708			/* We re-lookup the tp and chain based on index instead
1709			 * of having hard refs and locks to them, so do a sanity
1710			 * check if any of tp,chain,exts was replaced by the
1711			 * time we got here with a cookie from hardware.
1712			 */
1713			if (unlikely(n->tp != tp || n->tp->chain != n->chain ||
1714				     !tp->ops->get_exts)) {
1715				tcf_set_drop_reason(skb,
1716						    SKB_DROP_REASON_TC_COOKIE_ERROR);
1717				return TC_ACT_SHOT;
1718			}
1719
1720			exts = tp->ops->get_exts(tp, n->handle);
1721			if (unlikely(!exts || n->exts != exts)) {
1722				tcf_set_drop_reason(skb,
1723						    SKB_DROP_REASON_TC_COOKIE_ERROR);
1724				return TC_ACT_SHOT;
1725			}
1726
1727			n = NULL;
1728			err = tcf_exts_exec_ex(skb, exts, act_index, res);
1729		} else {
1730			if (tp->protocol != protocol &&
1731			    tp->protocol != htons(ETH_P_ALL))
1732				continue;
1733
1734			err = tc_classify(skb, tp, res);
1735		}
1736#ifdef CONFIG_NET_CLS_ACT
1737		if (unlikely(err == TC_ACT_RECLASSIFY && !compat_mode)) {
1738			first_tp = orig_tp;
1739			*last_executed_chain = first_tp->chain->index;
1740			goto reset;
1741		} else if (unlikely(TC_ACT_EXT_CMP(err, TC_ACT_GOTO_CHAIN))) {
1742			first_tp = res->goto_tp;
1743			*last_executed_chain = err & TC_ACT_EXT_VAL_MASK;
 
 
 
 
 
 
 
 
 
 
 
1744			goto reset;
1745		}
1746#endif
1747		if (err >= 0)
1748			return err;
1749	}
1750
1751	if (unlikely(n)) {
1752		tcf_set_drop_reason(skb,
1753				    SKB_DROP_REASON_TC_COOKIE_ERROR);
1754		return TC_ACT_SHOT;
1755	}
1756
1757	return TC_ACT_UNSPEC; /* signal: continue lookup */
1758#ifdef CONFIG_NET_CLS_ACT
1759reset:
1760	if (unlikely(limit++ >= max_reclassify_loop)) {
1761		net_notice_ratelimited("%u: reclassify loop, rule prio %u, protocol %02x\n",
1762				       tp->chain->block->index,
1763				       tp->prio & 0xffff,
1764				       ntohs(tp->protocol));
1765		tcf_set_drop_reason(skb,
1766				    SKB_DROP_REASON_TC_RECLASSIFY_LOOP);
1767		return TC_ACT_SHOT;
1768	}
1769
1770	tp = first_tp;
1771	goto reclassify;
1772#endif
1773}
1774
1775int tcf_classify(struct sk_buff *skb,
1776		 const struct tcf_block *block,
1777		 const struct tcf_proto *tp,
1778		 struct tcf_result *res, bool compat_mode)
1779{
1780#if !IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
1781	u32 last_executed_chain = 0;
1782
1783	return __tcf_classify(skb, tp, tp, res, compat_mode, NULL, 0,
1784			      &last_executed_chain);
1785#else
1786	u32 last_executed_chain = tp ? tp->chain->index : 0;
1787	struct tcf_exts_miss_cookie_node *n = NULL;
1788	const struct tcf_proto *orig_tp = tp;
1789	struct tc_skb_ext *ext;
1790	int act_index = 0;
1791	int ret;
1792
1793	if (block) {
1794		ext = skb_ext_find(skb, TC_SKB_EXT);
1795
1796		if (ext && (ext->chain || ext->act_miss)) {
1797			struct tcf_chain *fchain;
1798			u32 chain;
1799
1800			if (ext->act_miss) {
1801				n = tcf_exts_miss_cookie_lookup(ext->act_miss_cookie,
1802								&act_index);
1803				if (!n) {
1804					tcf_set_drop_reason(skb,
1805							    SKB_DROP_REASON_TC_COOKIE_ERROR);
1806					return TC_ACT_SHOT;
1807				}
1808
1809				chain = n->chain_index;
1810			} else {
1811				chain = ext->chain;
1812			}
1813
1814			fchain = tcf_chain_lookup_rcu(block, chain);
1815			if (!fchain) {
1816				tcf_set_drop_reason(skb,
1817						    SKB_DROP_REASON_TC_CHAIN_NOTFOUND);
1818
1819				return TC_ACT_SHOT;
1820			}
1821
1822			/* Consume, so cloned/redirect skbs won't inherit ext */
1823			skb_ext_del(skb, TC_SKB_EXT);
1824
1825			tp = rcu_dereference_bh(fchain->filter_chain);
1826			last_executed_chain = fchain->index;
1827		}
1828	}
1829
1830	ret = __tcf_classify(skb, tp, orig_tp, res, compat_mode, n, act_index,
1831			     &last_executed_chain);
1832
1833	if (tc_skb_ext_tc_enabled()) {
1834		/* If we missed on some chain */
1835		if (ret == TC_ACT_UNSPEC && last_executed_chain) {
1836			struct tc_skb_cb *cb = tc_skb_cb(skb);
1837
1838			ext = tc_skb_ext_alloc(skb);
1839			if (WARN_ON_ONCE(!ext)) {
1840				tcf_set_drop_reason(skb, SKB_DROP_REASON_NOMEM);
1841				return TC_ACT_SHOT;
1842			}
1843			ext->chain = last_executed_chain;
1844			ext->mru = cb->mru;
1845			ext->post_ct = cb->post_ct;
1846			ext->post_ct_snat = cb->post_ct_snat;
1847			ext->post_ct_dnat = cb->post_ct_dnat;
1848			ext->zone = cb->zone;
1849		}
1850	}
1851
1852	return ret;
1853#endif
1854}
1855EXPORT_SYMBOL(tcf_classify);
1856
1857struct tcf_chain_info {
1858	struct tcf_proto __rcu **pprev;
1859	struct tcf_proto __rcu *next;
1860};
1861
1862static struct tcf_proto *tcf_chain_tp_prev(struct tcf_chain *chain,
1863					   struct tcf_chain_info *chain_info)
1864{
1865	return tcf_chain_dereference(*chain_info->pprev, chain);
1866}
1867
1868static int tcf_chain_tp_insert(struct tcf_chain *chain,
1869			       struct tcf_chain_info *chain_info,
1870			       struct tcf_proto *tp)
1871{
1872	if (chain->flushing)
1873		return -EAGAIN;
1874
1875	RCU_INIT_POINTER(tp->next, tcf_chain_tp_prev(chain, chain_info));
1876	if (*chain_info->pprev == chain->filter_chain)
1877		tcf_chain0_head_change(chain, tp);
1878	tcf_proto_get(tp);
 
1879	rcu_assign_pointer(*chain_info->pprev, tp);
1880
1881	return 0;
1882}
1883
1884static void tcf_chain_tp_remove(struct tcf_chain *chain,
1885				struct tcf_chain_info *chain_info,
1886				struct tcf_proto *tp)
1887{
1888	struct tcf_proto *next = tcf_chain_dereference(chain_info->next, chain);
1889
1890	tcf_proto_mark_delete(tp);
1891	if (tp == chain->filter_chain)
1892		tcf_chain0_head_change(chain, next);
1893	RCU_INIT_POINTER(*chain_info->pprev, next);
1894}
1895
1896static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain,
1897					   struct tcf_chain_info *chain_info,
1898					   u32 protocol, u32 prio,
1899					   bool prio_allocate);
1900
1901/* Try to insert new proto.
1902 * If proto with specified priority already exists, free new proto
1903 * and return existing one.
1904 */
1905
1906static struct tcf_proto *tcf_chain_tp_insert_unique(struct tcf_chain *chain,
1907						    struct tcf_proto *tp_new,
1908						    u32 protocol, u32 prio,
1909						    bool rtnl_held)
1910{
1911	struct tcf_chain_info chain_info;
1912	struct tcf_proto *tp;
1913	int err = 0;
1914
1915	mutex_lock(&chain->filter_chain_lock);
1916
1917	if (tcf_proto_exists_destroying(chain, tp_new)) {
1918		mutex_unlock(&chain->filter_chain_lock);
1919		tcf_proto_destroy(tp_new, rtnl_held, false, NULL);
1920		return ERR_PTR(-EAGAIN);
1921	}
1922
1923	tp = tcf_chain_tp_find(chain, &chain_info,
1924			       protocol, prio, false);
1925	if (!tp)
1926		err = tcf_chain_tp_insert(chain, &chain_info, tp_new);
1927	mutex_unlock(&chain->filter_chain_lock);
1928
1929	if (tp) {
1930		tcf_proto_destroy(tp_new, rtnl_held, false, NULL);
1931		tp_new = tp;
1932	} else if (err) {
1933		tcf_proto_destroy(tp_new, rtnl_held, false, NULL);
1934		tp_new = ERR_PTR(err);
1935	}
1936
1937	return tp_new;
1938}
1939
1940static void tcf_chain_tp_delete_empty(struct tcf_chain *chain,
1941				      struct tcf_proto *tp, bool rtnl_held,
1942				      struct netlink_ext_ack *extack)
1943{
1944	struct tcf_chain_info chain_info;
1945	struct tcf_proto *tp_iter;
1946	struct tcf_proto **pprev;
1947	struct tcf_proto *next;
1948
1949	mutex_lock(&chain->filter_chain_lock);
1950
1951	/* Atomically find and remove tp from chain. */
1952	for (pprev = &chain->filter_chain;
1953	     (tp_iter = tcf_chain_dereference(*pprev, chain));
1954	     pprev = &tp_iter->next) {
1955		if (tp_iter == tp) {
1956			chain_info.pprev = pprev;
1957			chain_info.next = tp_iter->next;
1958			WARN_ON(tp_iter->deleting);
1959			break;
1960		}
1961	}
1962	/* Verify that tp still exists and no new filters were inserted
1963	 * concurrently.
1964	 * Mark tp for deletion if it is empty.
1965	 */
1966	if (!tp_iter || !tcf_proto_check_delete(tp)) {
1967		mutex_unlock(&chain->filter_chain_lock);
1968		return;
1969	}
1970
1971	tcf_proto_signal_destroying(chain, tp);
1972	next = tcf_chain_dereference(chain_info.next, chain);
1973	if (tp == chain->filter_chain)
1974		tcf_chain0_head_change(chain, next);
1975	RCU_INIT_POINTER(*chain_info.pprev, next);
1976	mutex_unlock(&chain->filter_chain_lock);
1977
1978	tcf_proto_put(tp, rtnl_held, extack);
1979}
1980
1981static struct tcf_proto *tcf_chain_tp_find(struct tcf_chain *chain,
1982					   struct tcf_chain_info *chain_info,
1983					   u32 protocol, u32 prio,
1984					   bool prio_allocate)
1985{
1986	struct tcf_proto **pprev;
1987	struct tcf_proto *tp;
1988
1989	/* Check the chain for existence of proto-tcf with this priority */
1990	for (pprev = &chain->filter_chain;
1991	     (tp = tcf_chain_dereference(*pprev, chain));
1992	     pprev = &tp->next) {
1993		if (tp->prio >= prio) {
1994			if (tp->prio == prio) {
1995				if (prio_allocate ||
1996				    (tp->protocol != protocol && protocol))
1997					return ERR_PTR(-EINVAL);
1998			} else {
1999				tp = NULL;
2000			}
2001			break;
2002		}
2003	}
2004	chain_info->pprev = pprev;
2005	if (tp) {
2006		chain_info->next = tp->next;
2007		tcf_proto_get(tp);
2008	} else {
2009		chain_info->next = NULL;
2010	}
2011	return tp;
2012}
2013
2014static int tcf_fill_node(struct net *net, struct sk_buff *skb,
2015			 struct tcf_proto *tp, struct tcf_block *block,
2016			 struct Qdisc *q, u32 parent, void *fh,
2017			 u32 portid, u32 seq, u16 flags, int event,
2018			 bool terse_dump, bool rtnl_held,
2019			 struct netlink_ext_ack *extack)
2020{
2021	struct tcmsg *tcm;
2022	struct nlmsghdr  *nlh;
2023	unsigned char *b = skb_tail_pointer(skb);
2024
2025	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
2026	if (!nlh)
2027		goto out_nlmsg_trim;
2028	tcm = nlmsg_data(nlh);
2029	tcm->tcm_family = AF_UNSPEC;
2030	tcm->tcm__pad1 = 0;
2031	tcm->tcm__pad2 = 0;
2032	if (q) {
2033		tcm->tcm_ifindex = qdisc_dev(q)->ifindex;
2034		tcm->tcm_parent = parent;
2035	} else {
2036		tcm->tcm_ifindex = TCM_IFINDEX_MAGIC_BLOCK;
2037		tcm->tcm_block_index = block->index;
2038	}
2039	tcm->tcm_info = TC_H_MAKE(tp->prio, tp->protocol);
2040	if (nla_put_string(skb, TCA_KIND, tp->ops->kind))
2041		goto nla_put_failure;
2042	if (nla_put_u32(skb, TCA_CHAIN, tp->chain->index))
2043		goto nla_put_failure;
2044	if (!fh) {
2045		tcm->tcm_handle = 0;
2046	} else if (terse_dump) {
2047		if (tp->ops->terse_dump) {
2048			if (tp->ops->terse_dump(net, tp, fh, skb, tcm,
2049						rtnl_held) < 0)
2050				goto nla_put_failure;
2051		} else {
2052			goto cls_op_not_supp;
2053		}
2054	} else {
2055		if (tp->ops->dump &&
2056		    tp->ops->dump(net, tp, fh, skb, tcm, rtnl_held) < 0)
2057			goto nla_put_failure;
2058	}
2059
2060	if (extack && extack->_msg &&
2061	    nla_put_string(skb, TCA_EXT_WARN_MSG, extack->_msg))
2062		goto nla_put_failure;
2063
2064	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
2065
2066	return skb->len;
2067
2068out_nlmsg_trim:
2069nla_put_failure:
2070cls_op_not_supp:
2071	nlmsg_trim(skb, b);
2072	return -1;
2073}
2074
2075static int tfilter_notify(struct net *net, struct sk_buff *oskb,
2076			  struct nlmsghdr *n, struct tcf_proto *tp,
2077			  struct tcf_block *block, struct Qdisc *q,
2078			  u32 parent, void *fh, int event, bool unicast,
2079			  bool rtnl_held, struct netlink_ext_ack *extack)
2080{
2081	struct sk_buff *skb;
2082	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
2083	int err = 0;
2084
2085	if (!unicast && !rtnl_notify_needed(net, n->nlmsg_flags, RTNLGRP_TC))
2086		return 0;
2087
2088	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2089	if (!skb)
2090		return -ENOBUFS;
2091
2092	if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid,
2093			  n->nlmsg_seq, n->nlmsg_flags, event,
2094			  false, rtnl_held, extack) <= 0) {
2095		kfree_skb(skb);
2096		return -EINVAL;
2097	}
2098
2099	if (unicast)
2100		err = rtnl_unicast(skb, net, portid);
2101	else
2102		err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
2103				     n->nlmsg_flags & NLM_F_ECHO);
 
 
 
2104	return err;
2105}
2106
2107static int tfilter_del_notify(struct net *net, struct sk_buff *oskb,
2108			      struct nlmsghdr *n, struct tcf_proto *tp,
2109			      struct tcf_block *block, struct Qdisc *q,
2110			      u32 parent, void *fh, bool *last, bool rtnl_held,
2111			      struct netlink_ext_ack *extack)
2112{
2113	struct sk_buff *skb;
2114	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
2115	int err;
2116
2117	if (!rtnl_notify_needed(net, n->nlmsg_flags, RTNLGRP_TC))
2118		return tp->ops->delete(tp, fh, last, rtnl_held, extack);
2119
2120	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2121	if (!skb)
2122		return -ENOBUFS;
2123
2124	if (tcf_fill_node(net, skb, tp, block, q, parent, fh, portid,
2125			  n->nlmsg_seq, n->nlmsg_flags, RTM_DELTFILTER,
2126			  false, rtnl_held, extack) <= 0) {
2127		NL_SET_ERR_MSG(extack, "Failed to build del event notification");
2128		kfree_skb(skb);
2129		return -EINVAL;
2130	}
2131
2132	err = tp->ops->delete(tp, fh, last, rtnl_held, extack);
2133	if (err) {
2134		kfree_skb(skb);
2135		return err;
2136	}
2137
2138	err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
2139			     n->nlmsg_flags & NLM_F_ECHO);
 
 
 
2140	if (err < 0)
2141		NL_SET_ERR_MSG(extack, "Failed to send filter delete notification");
2142
 
 
2143	return err;
2144}
2145
2146static void tfilter_notify_chain(struct net *net, struct sk_buff *oskb,
2147				 struct tcf_block *block, struct Qdisc *q,
2148				 u32 parent, struct nlmsghdr *n,
2149				 struct tcf_chain *chain, int event,
2150				 struct netlink_ext_ack *extack)
2151{
2152	struct tcf_proto *tp;
2153
2154	for (tp = tcf_get_next_proto(chain, NULL);
2155	     tp; tp = tcf_get_next_proto(chain, tp))
2156		tfilter_notify(net, oskb, n, tp, block, q, parent, NULL,
2157			       event, false, true, extack);
2158}
2159
2160static void tfilter_put(struct tcf_proto *tp, void *fh)
2161{
2162	if (tp->ops->put && fh)
2163		tp->ops->put(tp, fh);
2164}
2165
2166static bool is_qdisc_ingress(__u32 classid)
2167{
2168	return (TC_H_MIN(classid) == TC_H_MIN(TC_H_MIN_INGRESS));
2169}
2170
2171static int tc_new_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
2172			  struct netlink_ext_ack *extack)
2173{
2174	struct net *net = sock_net(skb->sk);
2175	struct nlattr *tca[TCA_MAX + 1];
2176	char name[IFNAMSIZ];
2177	struct tcmsg *t;
2178	u32 protocol;
2179	u32 prio;
2180	bool prio_allocate;
2181	u32 parent;
2182	u32 chain_index;
2183	struct Qdisc *q;
2184	struct tcf_chain_info chain_info;
2185	struct tcf_chain *chain;
2186	struct tcf_block *block;
2187	struct tcf_proto *tp;
2188	unsigned long cl;
2189	void *fh;
2190	int err;
2191	int tp_created;
2192	bool rtnl_held = false;
2193	u32 flags;
 
 
2194
2195replay:
2196	tp_created = 0;
2197
2198	err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
2199				     rtm_tca_policy, extack);
2200	if (err < 0)
2201		return err;
2202
2203	t = nlmsg_data(n);
2204	protocol = TC_H_MIN(t->tcm_info);
2205	prio = TC_H_MAJ(t->tcm_info);
2206	prio_allocate = false;
2207	parent = t->tcm_parent;
2208	tp = NULL;
2209	cl = 0;
2210	block = NULL;
2211	q = NULL;
2212	chain = NULL;
2213	flags = 0;
2214
2215	if (prio == 0) {
2216		/* If no priority is provided by the user,
2217		 * we allocate one.
2218		 */
2219		if (n->nlmsg_flags & NLM_F_CREATE) {
2220			prio = TC_H_MAKE(0x80000000U, 0U);
2221			prio_allocate = true;
2222		} else {
2223			NL_SET_ERR_MSG(extack, "Invalid filter command with priority of zero");
2224			return -ENOENT;
2225		}
2226	}
2227
2228	/* Find head of filter chain. */
2229
2230	err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack);
2231	if (err)
2232		return err;
2233
2234	if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
2235		NL_SET_ERR_MSG(extack, "Specified TC filter name too long");
2236		err = -EINVAL;
2237		goto errout;
2238	}
2239
2240	/* Take rtnl mutex if rtnl_held was set to true on previous iteration,
2241	 * block is shared (no qdisc found), qdisc is not unlocked, classifier
2242	 * type is not specified, classifier is not unlocked.
2243	 */
2244	if (rtnl_held ||
2245	    (q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
2246	    !tcf_proto_is_unlocked(name)) {
2247		rtnl_held = true;
2248		rtnl_lock();
2249	}
2250
2251	err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack);
2252	if (err)
2253		goto errout;
2254
2255	block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index,
2256				 extack);
2257	if (IS_ERR(block)) {
2258		err = PTR_ERR(block);
2259		goto errout;
2260	}
2261	block->classid = parent;
2262
2263	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2264	if (chain_index > TC_ACT_EXT_VAL_MASK) {
2265		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2266		err = -EINVAL;
2267		goto errout;
2268	}
2269	chain = tcf_chain_get(block, chain_index, true);
2270	if (!chain) {
2271		NL_SET_ERR_MSG(extack, "Cannot create specified filter chain");
2272		err = -ENOMEM;
2273		goto errout;
2274	}
2275
2276	mutex_lock(&chain->filter_chain_lock);
2277	tp = tcf_chain_tp_find(chain, &chain_info, protocol,
2278			       prio, prio_allocate);
2279	if (IS_ERR(tp)) {
2280		NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
2281		err = PTR_ERR(tp);
2282		goto errout_locked;
2283	}
2284
2285	if (tp == NULL) {
2286		struct tcf_proto *tp_new = NULL;
2287
2288		if (chain->flushing) {
2289			err = -EAGAIN;
2290			goto errout_locked;
2291		}
2292
2293		/* Proto-tcf does not exist, create new one */
2294
2295		if (tca[TCA_KIND] == NULL || !protocol) {
2296			NL_SET_ERR_MSG(extack, "Filter kind and protocol must be specified");
2297			err = -EINVAL;
2298			goto errout_locked;
2299		}
2300
2301		if (!(n->nlmsg_flags & NLM_F_CREATE)) {
2302			NL_SET_ERR_MSG(extack, "Need both RTM_NEWTFILTER and NLM_F_CREATE to create a new filter");
2303			err = -ENOENT;
2304			goto errout_locked;
2305		}
2306
2307		if (prio_allocate)
2308			prio = tcf_auto_prio(tcf_chain_tp_prev(chain,
2309							       &chain_info));
2310
2311		mutex_unlock(&chain->filter_chain_lock);
2312		tp_new = tcf_proto_create(name, protocol, prio, chain,
2313					  rtnl_held, extack);
 
2314		if (IS_ERR(tp_new)) {
2315			err = PTR_ERR(tp_new);
2316			goto errout_tp;
2317		}
2318
2319		tp_created = 1;
2320		tp = tcf_chain_tp_insert_unique(chain, tp_new, protocol, prio,
2321						rtnl_held);
2322		if (IS_ERR(tp)) {
2323			err = PTR_ERR(tp);
2324			goto errout_tp;
2325		}
2326	} else {
2327		mutex_unlock(&chain->filter_chain_lock);
2328	}
2329
2330	if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
2331		NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
2332		err = -EINVAL;
2333		goto errout;
2334	}
2335
2336	fh = tp->ops->get(tp, t->tcm_handle);
2337
2338	if (!fh) {
2339		if (!(n->nlmsg_flags & NLM_F_CREATE)) {
2340			NL_SET_ERR_MSG(extack, "Need both RTM_NEWTFILTER and NLM_F_CREATE to create a new filter");
2341			err = -ENOENT;
2342			goto errout;
2343		}
2344	} else if (n->nlmsg_flags & NLM_F_EXCL) {
2345		tfilter_put(tp, fh);
2346		NL_SET_ERR_MSG(extack, "Filter already exists");
2347		err = -EEXIST;
2348		goto errout;
2349	}
2350
2351	if (chain->tmplt_ops && chain->tmplt_ops != tp->ops) {
2352		tfilter_put(tp, fh);
2353		NL_SET_ERR_MSG(extack, "Chain template is set to a different filter kind");
2354		err = -EINVAL;
2355		goto errout;
2356	}
2357
2358	if (!(n->nlmsg_flags & NLM_F_CREATE))
2359		flags |= TCA_ACT_FLAGS_REPLACE;
2360	if (!rtnl_held)
2361		flags |= TCA_ACT_FLAGS_NO_RTNL;
2362	if (is_qdisc_ingress(parent))
2363		flags |= TCA_ACT_FLAGS_AT_INGRESS;
2364	err = tp->ops->change(net, skb, tp, cl, t->tcm_handle, tca, &fh,
2365			      flags, extack);
 
2366	if (err == 0) {
2367		tfilter_notify(net, skb, n, tp, block, q, parent, fh,
2368			       RTM_NEWTFILTER, false, rtnl_held, extack);
2369		tfilter_put(tp, fh);
2370		/* q pointer is NULL for shared blocks */
2371		if (q)
2372			q->flags &= ~TCQ_F_CAN_BYPASS;
2373	}
2374
2375errout:
2376	if (err && tp_created)
2377		tcf_chain_tp_delete_empty(chain, tp, rtnl_held, NULL);
2378errout_tp:
2379	if (chain) {
2380		if (tp && !IS_ERR(tp))
2381			tcf_proto_put(tp, rtnl_held, NULL);
2382		if (!tp_created)
2383			tcf_chain_put(chain);
2384	}
2385	tcf_block_release(q, block, rtnl_held);
2386
2387	if (rtnl_held)
2388		rtnl_unlock();
2389
2390	if (err == -EAGAIN) {
2391		/* Take rtnl lock in case EAGAIN is caused by concurrent flush
2392		 * of target chain.
2393		 */
2394		rtnl_held = true;
2395		/* Replay the request. */
2396		goto replay;
2397	}
2398	return err;
2399
2400errout_locked:
2401	mutex_unlock(&chain->filter_chain_lock);
2402	goto errout;
2403}
2404
2405static int tc_del_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
2406			  struct netlink_ext_ack *extack)
2407{
2408	struct net *net = sock_net(skb->sk);
2409	struct nlattr *tca[TCA_MAX + 1];
2410	char name[IFNAMSIZ];
2411	struct tcmsg *t;
2412	u32 protocol;
2413	u32 prio;
2414	u32 parent;
2415	u32 chain_index;
2416	struct Qdisc *q = NULL;
2417	struct tcf_chain_info chain_info;
2418	struct tcf_chain *chain = NULL;
2419	struct tcf_block *block = NULL;
2420	struct tcf_proto *tp = NULL;
2421	unsigned long cl = 0;
2422	void *fh = NULL;
2423	int err;
2424	bool rtnl_held = false;
2425
 
 
 
2426	err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
2427				     rtm_tca_policy, extack);
2428	if (err < 0)
2429		return err;
2430
2431	t = nlmsg_data(n);
2432	protocol = TC_H_MIN(t->tcm_info);
2433	prio = TC_H_MAJ(t->tcm_info);
2434	parent = t->tcm_parent;
2435
2436	if (prio == 0 && (protocol || t->tcm_handle || tca[TCA_KIND])) {
2437		NL_SET_ERR_MSG(extack, "Cannot flush filters with protocol, handle or kind set");
2438		return -ENOENT;
2439	}
2440
2441	/* Find head of filter chain. */
2442
2443	err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack);
2444	if (err)
2445		return err;
2446
2447	if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
2448		NL_SET_ERR_MSG(extack, "Specified TC filter name too long");
2449		err = -EINVAL;
2450		goto errout;
2451	}
2452	/* Take rtnl mutex if flushing whole chain, block is shared (no qdisc
2453	 * found), qdisc is not unlocked, classifier type is not specified,
2454	 * classifier is not unlocked.
2455	 */
2456	if (!prio ||
2457	    (q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
2458	    !tcf_proto_is_unlocked(name)) {
2459		rtnl_held = true;
2460		rtnl_lock();
2461	}
2462
2463	err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack);
2464	if (err)
2465		goto errout;
2466
2467	block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index,
2468				 extack);
2469	if (IS_ERR(block)) {
2470		err = PTR_ERR(block);
2471		goto errout;
2472	}
2473
2474	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2475	if (chain_index > TC_ACT_EXT_VAL_MASK) {
2476		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2477		err = -EINVAL;
2478		goto errout;
2479	}
2480	chain = tcf_chain_get(block, chain_index, false);
2481	if (!chain) {
2482		/* User requested flush on non-existent chain. Nothing to do,
2483		 * so just return success.
2484		 */
2485		if (prio == 0) {
2486			err = 0;
2487			goto errout;
2488		}
2489		NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
2490		err = -ENOENT;
2491		goto errout;
2492	}
2493
2494	if (prio == 0) {
2495		tfilter_notify_chain(net, skb, block, q, parent, n,
2496				     chain, RTM_DELTFILTER, extack);
2497		tcf_chain_flush(chain, rtnl_held);
2498		err = 0;
2499		goto errout;
2500	}
2501
2502	mutex_lock(&chain->filter_chain_lock);
2503	tp = tcf_chain_tp_find(chain, &chain_info, protocol,
2504			       prio, false);
2505	if (!tp || IS_ERR(tp)) {
2506		NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
2507		err = tp ? PTR_ERR(tp) : -ENOENT;
2508		goto errout_locked;
2509	} else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
2510		NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
2511		err = -EINVAL;
2512		goto errout_locked;
2513	} else if (t->tcm_handle == 0) {
2514		tcf_proto_signal_destroying(chain, tp);
2515		tcf_chain_tp_remove(chain, &chain_info, tp);
2516		mutex_unlock(&chain->filter_chain_lock);
2517
2518		tcf_proto_put(tp, rtnl_held, NULL);
2519		tfilter_notify(net, skb, n, tp, block, q, parent, fh,
2520			       RTM_DELTFILTER, false, rtnl_held, extack);
2521		err = 0;
2522		goto errout;
2523	}
2524	mutex_unlock(&chain->filter_chain_lock);
2525
2526	fh = tp->ops->get(tp, t->tcm_handle);
2527
2528	if (!fh) {
2529		NL_SET_ERR_MSG(extack, "Specified filter handle not found");
2530		err = -ENOENT;
2531	} else {
2532		bool last;
2533
2534		err = tfilter_del_notify(net, skb, n, tp, block, q, parent, fh,
2535					 &last, rtnl_held, extack);
 
2536
2537		if (err)
2538			goto errout;
2539		if (last)
2540			tcf_chain_tp_delete_empty(chain, tp, rtnl_held, extack);
2541	}
2542
2543errout:
2544	if (chain) {
2545		if (tp && !IS_ERR(tp))
2546			tcf_proto_put(tp, rtnl_held, NULL);
2547		tcf_chain_put(chain);
2548	}
2549	tcf_block_release(q, block, rtnl_held);
2550
2551	if (rtnl_held)
2552		rtnl_unlock();
2553
2554	return err;
2555
2556errout_locked:
2557	mutex_unlock(&chain->filter_chain_lock);
2558	goto errout;
2559}
2560
2561static int tc_get_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
2562			  struct netlink_ext_ack *extack)
2563{
2564	struct net *net = sock_net(skb->sk);
2565	struct nlattr *tca[TCA_MAX + 1];
2566	char name[IFNAMSIZ];
2567	struct tcmsg *t;
2568	u32 protocol;
2569	u32 prio;
2570	u32 parent;
2571	u32 chain_index;
2572	struct Qdisc *q = NULL;
2573	struct tcf_chain_info chain_info;
2574	struct tcf_chain *chain = NULL;
2575	struct tcf_block *block = NULL;
2576	struct tcf_proto *tp = NULL;
2577	unsigned long cl = 0;
2578	void *fh = NULL;
2579	int err;
2580	bool rtnl_held = false;
2581
2582	err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
2583				     rtm_tca_policy, extack);
2584	if (err < 0)
2585		return err;
2586
2587	t = nlmsg_data(n);
2588	protocol = TC_H_MIN(t->tcm_info);
2589	prio = TC_H_MAJ(t->tcm_info);
2590	parent = t->tcm_parent;
2591
2592	if (prio == 0) {
2593		NL_SET_ERR_MSG(extack, "Invalid filter command with priority of zero");
2594		return -ENOENT;
2595	}
2596
2597	/* Find head of filter chain. */
2598
2599	err = __tcf_qdisc_find(net, &q, &parent, t->tcm_ifindex, false, extack);
2600	if (err)
2601		return err;
2602
2603	if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
2604		NL_SET_ERR_MSG(extack, "Specified TC filter name too long");
2605		err = -EINVAL;
2606		goto errout;
2607	}
2608	/* Take rtnl mutex if block is shared (no qdisc found), qdisc is not
2609	 * unlocked, classifier type is not specified, classifier is not
2610	 * unlocked.
2611	 */
2612	if ((q && !(q->ops->cl_ops->flags & QDISC_CLASS_OPS_DOIT_UNLOCKED)) ||
2613	    !tcf_proto_is_unlocked(name)) {
2614		rtnl_held = true;
2615		rtnl_lock();
2616	}
2617
2618	err = __tcf_qdisc_cl_find(q, parent, &cl, t->tcm_ifindex, extack);
2619	if (err)
2620		goto errout;
2621
2622	block = __tcf_block_find(net, q, cl, t->tcm_ifindex, t->tcm_block_index,
2623				 extack);
2624	if (IS_ERR(block)) {
2625		err = PTR_ERR(block);
2626		goto errout;
2627	}
2628
2629	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
2630	if (chain_index > TC_ACT_EXT_VAL_MASK) {
2631		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
2632		err = -EINVAL;
2633		goto errout;
2634	}
2635	chain = tcf_chain_get(block, chain_index, false);
2636	if (!chain) {
2637		NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
2638		err = -EINVAL;
2639		goto errout;
2640	}
2641
2642	mutex_lock(&chain->filter_chain_lock);
2643	tp = tcf_chain_tp_find(chain, &chain_info, protocol,
2644			       prio, false);
2645	mutex_unlock(&chain->filter_chain_lock);
2646	if (!tp || IS_ERR(tp)) {
2647		NL_SET_ERR_MSG(extack, "Filter with specified priority/protocol not found");
2648		err = tp ? PTR_ERR(tp) : -ENOENT;
2649		goto errout;
2650	} else if (tca[TCA_KIND] && nla_strcmp(tca[TCA_KIND], tp->ops->kind)) {
2651		NL_SET_ERR_MSG(extack, "Specified filter kind does not match existing one");
2652		err = -EINVAL;
2653		goto errout;
2654	}
2655
2656	fh = tp->ops->get(tp, t->tcm_handle);
2657
2658	if (!fh) {
2659		NL_SET_ERR_MSG(extack, "Specified filter handle not found");
2660		err = -ENOENT;
2661	} else {
2662		err = tfilter_notify(net, skb, n, tp, block, q, parent,
2663				     fh, RTM_NEWTFILTER, true, rtnl_held, NULL);
2664		if (err < 0)
2665			NL_SET_ERR_MSG(extack, "Failed to send filter notify message");
2666	}
2667
2668	tfilter_put(tp, fh);
2669errout:
2670	if (chain) {
2671		if (tp && !IS_ERR(tp))
2672			tcf_proto_put(tp, rtnl_held, NULL);
2673		tcf_chain_put(chain);
2674	}
2675	tcf_block_release(q, block, rtnl_held);
2676
2677	if (rtnl_held)
2678		rtnl_unlock();
2679
2680	return err;
2681}
2682
2683struct tcf_dump_args {
2684	struct tcf_walker w;
2685	struct sk_buff *skb;
2686	struct netlink_callback *cb;
2687	struct tcf_block *block;
2688	struct Qdisc *q;
2689	u32 parent;
2690	bool terse_dump;
2691};
2692
2693static int tcf_node_dump(struct tcf_proto *tp, void *n, struct tcf_walker *arg)
2694{
2695	struct tcf_dump_args *a = (void *)arg;
2696	struct net *net = sock_net(a->skb->sk);
2697
2698	return tcf_fill_node(net, a->skb, tp, a->block, a->q, a->parent,
2699			     n, NETLINK_CB(a->cb->skb).portid,
2700			     a->cb->nlh->nlmsg_seq, NLM_F_MULTI,
2701			     RTM_NEWTFILTER, a->terse_dump, true, NULL);
2702}
2703
2704static bool tcf_chain_dump(struct tcf_chain *chain, struct Qdisc *q, u32 parent,
2705			   struct sk_buff *skb, struct netlink_callback *cb,
2706			   long index_start, long *p_index, bool terse)
2707{
2708	struct net *net = sock_net(skb->sk);
2709	struct tcf_block *block = chain->block;
2710	struct tcmsg *tcm = nlmsg_data(cb->nlh);
2711	struct tcf_proto *tp, *tp_prev;
2712	struct tcf_dump_args arg;
2713
2714	for (tp = __tcf_get_next_proto(chain, NULL);
2715	     tp;
2716	     tp_prev = tp,
2717		     tp = __tcf_get_next_proto(chain, tp),
2718		     tcf_proto_put(tp_prev, true, NULL),
2719		     (*p_index)++) {
2720		if (*p_index < index_start)
2721			continue;
2722		if (TC_H_MAJ(tcm->tcm_info) &&
2723		    TC_H_MAJ(tcm->tcm_info) != tp->prio)
2724			continue;
2725		if (TC_H_MIN(tcm->tcm_info) &&
2726		    TC_H_MIN(tcm->tcm_info) != tp->protocol)
2727			continue;
2728		if (*p_index > index_start)
2729			memset(&cb->args[1], 0,
2730			       sizeof(cb->args) - sizeof(cb->args[0]));
2731		if (cb->args[1] == 0) {
2732			if (tcf_fill_node(net, skb, tp, block, q, parent, NULL,
2733					  NETLINK_CB(cb->skb).portid,
2734					  cb->nlh->nlmsg_seq, NLM_F_MULTI,
2735					  RTM_NEWTFILTER, false, true, NULL) <= 0)
2736				goto errout;
2737			cb->args[1] = 1;
2738		}
2739		if (!tp->ops->walk)
2740			continue;
2741		arg.w.fn = tcf_node_dump;
2742		arg.skb = skb;
2743		arg.cb = cb;
2744		arg.block = block;
2745		arg.q = q;
2746		arg.parent = parent;
2747		arg.w.stop = 0;
2748		arg.w.skip = cb->args[1] - 1;
2749		arg.w.count = 0;
2750		arg.w.cookie = cb->args[2];
2751		arg.terse_dump = terse;
2752		tp->ops->walk(tp, &arg.w, true);
2753		cb->args[2] = arg.w.cookie;
2754		cb->args[1] = arg.w.count + 1;
2755		if (arg.w.stop)
2756			goto errout;
2757	}
2758	return true;
2759
2760errout:
2761	tcf_proto_put(tp, true, NULL);
2762	return false;
2763}
2764
2765static const struct nla_policy tcf_tfilter_dump_policy[TCA_MAX + 1] = {
2766	[TCA_CHAIN]      = { .type = NLA_U32 },
2767	[TCA_DUMP_FLAGS] = NLA_POLICY_BITFIELD32(TCA_DUMP_FLAGS_TERSE),
2768};
2769
2770/* called with RTNL */
2771static int tc_dump_tfilter(struct sk_buff *skb, struct netlink_callback *cb)
2772{
2773	struct tcf_chain *chain, *chain_prev;
2774	struct net *net = sock_net(skb->sk);
2775	struct nlattr *tca[TCA_MAX + 1];
2776	struct Qdisc *q = NULL;
2777	struct tcf_block *block;
2778	struct tcmsg *tcm = nlmsg_data(cb->nlh);
2779	bool terse_dump = false;
2780	long index_start;
2781	long index;
2782	u32 parent;
2783	int err;
2784
2785	if (nlmsg_len(cb->nlh) < sizeof(*tcm))
2786		return skb->len;
2787
2788	err = nlmsg_parse_deprecated(cb->nlh, sizeof(*tcm), tca, TCA_MAX,
2789				     tcf_tfilter_dump_policy, cb->extack);
2790	if (err)
2791		return err;
2792
2793	if (tca[TCA_DUMP_FLAGS]) {
2794		struct nla_bitfield32 flags =
2795			nla_get_bitfield32(tca[TCA_DUMP_FLAGS]);
2796
2797		terse_dump = flags.value & TCA_DUMP_FLAGS_TERSE;
2798	}
2799
2800	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
2801		block = tcf_block_refcnt_get(net, tcm->tcm_block_index);
2802		if (!block)
2803			goto out;
2804		/* If we work with block index, q is NULL and parent value
2805		 * will never be used in the following code. The check
2806		 * in tcf_fill_node prevents it. However, compiler does not
2807		 * see that far, so set parent to zero to silence the warning
2808		 * about parent being uninitialized.
2809		 */
2810		parent = 0;
2811	} else {
2812		const struct Qdisc_class_ops *cops;
2813		struct net_device *dev;
2814		unsigned long cl = 0;
2815
2816		dev = __dev_get_by_index(net, tcm->tcm_ifindex);
2817		if (!dev)
2818			return skb->len;
2819
2820		parent = tcm->tcm_parent;
2821		if (!parent)
2822			q = rtnl_dereference(dev->qdisc);
2823		else
 
2824			q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
 
2825		if (!q)
2826			goto out;
2827		cops = q->ops->cl_ops;
2828		if (!cops)
2829			goto out;
2830		if (!cops->tcf_block)
2831			goto out;
2832		if (TC_H_MIN(tcm->tcm_parent)) {
2833			cl = cops->find(q, tcm->tcm_parent);
2834			if (cl == 0)
2835				goto out;
2836		}
2837		block = cops->tcf_block(q, cl, NULL);
2838		if (!block)
2839			goto out;
2840		parent = block->classid;
2841		if (tcf_block_shared(block))
2842			q = NULL;
2843	}
2844
2845	index_start = cb->args[0];
2846	index = 0;
2847
2848	for (chain = __tcf_get_next_chain(block, NULL);
2849	     chain;
2850	     chain_prev = chain,
2851		     chain = __tcf_get_next_chain(block, chain),
2852		     tcf_chain_put(chain_prev)) {
2853		if (tca[TCA_CHAIN] &&
2854		    nla_get_u32(tca[TCA_CHAIN]) != chain->index)
2855			continue;
2856		if (!tcf_chain_dump(chain, q, parent, skb, cb,
2857				    index_start, &index, terse_dump)) {
2858			tcf_chain_put(chain);
2859			err = -EMSGSIZE;
2860			break;
2861		}
2862	}
2863
2864	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK)
2865		tcf_block_refcnt_put(block, true);
2866	cb->args[0] = index;
2867
2868out:
2869	/* If we did no progress, the error (EMSGSIZE) is real */
2870	if (skb->len == 0 && err)
2871		return err;
2872	return skb->len;
2873}
2874
2875static int tc_chain_fill_node(const struct tcf_proto_ops *tmplt_ops,
2876			      void *tmplt_priv, u32 chain_index,
2877			      struct net *net, struct sk_buff *skb,
2878			      struct tcf_block *block,
2879			      u32 portid, u32 seq, u16 flags, int event,
2880			      struct netlink_ext_ack *extack)
2881{
2882	unsigned char *b = skb_tail_pointer(skb);
2883	const struct tcf_proto_ops *ops;
2884	struct nlmsghdr *nlh;
2885	struct tcmsg *tcm;
2886	void *priv;
2887
2888	ops = tmplt_ops;
2889	priv = tmplt_priv;
2890
2891	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
2892	if (!nlh)
2893		goto out_nlmsg_trim;
2894	tcm = nlmsg_data(nlh);
2895	tcm->tcm_family = AF_UNSPEC;
2896	tcm->tcm__pad1 = 0;
2897	tcm->tcm__pad2 = 0;
2898	tcm->tcm_handle = 0;
2899	if (block->q) {
2900		tcm->tcm_ifindex = qdisc_dev(block->q)->ifindex;
2901		tcm->tcm_parent = block->q->handle;
2902	} else {
2903		tcm->tcm_ifindex = TCM_IFINDEX_MAGIC_BLOCK;
2904		tcm->tcm_block_index = block->index;
2905	}
2906
2907	if (nla_put_u32(skb, TCA_CHAIN, chain_index))
2908		goto nla_put_failure;
2909
2910	if (ops) {
2911		if (nla_put_string(skb, TCA_KIND, ops->kind))
2912			goto nla_put_failure;
2913		if (ops->tmplt_dump(skb, net, priv) < 0)
2914			goto nla_put_failure;
2915	}
2916
2917	if (extack && extack->_msg &&
2918	    nla_put_string(skb, TCA_EXT_WARN_MSG, extack->_msg))
2919		goto out_nlmsg_trim;
2920
2921	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
2922
2923	return skb->len;
2924
2925out_nlmsg_trim:
2926nla_put_failure:
2927	nlmsg_trim(skb, b);
2928	return -EMSGSIZE;
2929}
2930
2931static int tc_chain_notify(struct tcf_chain *chain, struct sk_buff *oskb,
2932			   u32 seq, u16 flags, int event, bool unicast,
2933			   struct netlink_ext_ack *extack)
2934{
2935	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
2936	struct tcf_block *block = chain->block;
2937	struct net *net = block->net;
2938	struct sk_buff *skb;
2939	int err = 0;
2940
2941	if (!unicast && !rtnl_notify_needed(net, flags, RTNLGRP_TC))
2942		return 0;
2943
2944	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2945	if (!skb)
2946		return -ENOBUFS;
2947
2948	if (tc_chain_fill_node(chain->tmplt_ops, chain->tmplt_priv,
2949			       chain->index, net, skb, block, portid,
2950			       seq, flags, event, extack) <= 0) {
2951		kfree_skb(skb);
2952		return -EINVAL;
2953	}
2954
2955	if (unicast)
2956		err = rtnl_unicast(skb, net, portid);
2957	else
2958		err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
2959				     flags & NLM_F_ECHO);
2960
 
 
2961	return err;
2962}
2963
2964static int tc_chain_notify_delete(const struct tcf_proto_ops *tmplt_ops,
2965				  void *tmplt_priv, u32 chain_index,
2966				  struct tcf_block *block, struct sk_buff *oskb,
2967				  u32 seq, u16 flags)
2968{
2969	u32 portid = oskb ? NETLINK_CB(oskb).portid : 0;
2970	struct net *net = block->net;
2971	struct sk_buff *skb;
2972
2973	if (!rtnl_notify_needed(net, flags, RTNLGRP_TC))
2974		return 0;
2975
2976	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
2977	if (!skb)
2978		return -ENOBUFS;
2979
2980	if (tc_chain_fill_node(tmplt_ops, tmplt_priv, chain_index, net, skb,
2981			       block, portid, seq, flags, RTM_DELCHAIN, NULL) <= 0) {
2982		kfree_skb(skb);
2983		return -EINVAL;
2984	}
2985
 
 
 
2986	return rtnetlink_send(skb, net, portid, RTNLGRP_TC, flags & NLM_F_ECHO);
2987}
2988
2989static int tc_chain_tmplt_add(struct tcf_chain *chain, struct net *net,
2990			      struct nlattr **tca,
2991			      struct netlink_ext_ack *extack)
2992{
2993	const struct tcf_proto_ops *ops;
2994	char name[IFNAMSIZ];
2995	void *tmplt_priv;
2996
2997	/* If kind is not set, user did not specify template. */
2998	if (!tca[TCA_KIND])
2999		return 0;
3000
3001	if (tcf_proto_check_kind(tca[TCA_KIND], name)) {
3002		NL_SET_ERR_MSG(extack, "Specified TC chain template name too long");
3003		return -EINVAL;
3004	}
3005
3006	ops = tcf_proto_lookup_ops(name, true, extack);
3007	if (IS_ERR(ops))
3008		return PTR_ERR(ops);
3009	if (!ops->tmplt_create || !ops->tmplt_destroy || !ops->tmplt_dump ||
3010	    !ops->tmplt_reoffload) {
3011		NL_SET_ERR_MSG(extack, "Chain templates are not supported with specified classifier");
3012		module_put(ops->owner);
3013		return -EOPNOTSUPP;
3014	}
3015
3016	tmplt_priv = ops->tmplt_create(net, chain, tca, extack);
3017	if (IS_ERR(tmplt_priv)) {
3018		module_put(ops->owner);
3019		return PTR_ERR(tmplt_priv);
3020	}
3021	chain->tmplt_ops = ops;
3022	chain->tmplt_priv = tmplt_priv;
3023	return 0;
3024}
3025
3026static void tc_chain_tmplt_del(const struct tcf_proto_ops *tmplt_ops,
3027			       void *tmplt_priv)
3028{
3029	/* If template ops are set, no work to do for us. */
3030	if (!tmplt_ops)
3031		return;
3032
3033	tmplt_ops->tmplt_destroy(tmplt_priv);
3034	module_put(tmplt_ops->owner);
3035}
3036
3037/* Add/delete/get a chain */
3038
3039static int tc_ctl_chain(struct sk_buff *skb, struct nlmsghdr *n,
3040			struct netlink_ext_ack *extack)
3041{
3042	struct net *net = sock_net(skb->sk);
3043	struct nlattr *tca[TCA_MAX + 1];
3044	struct tcmsg *t;
3045	u32 parent;
3046	u32 chain_index;
3047	struct Qdisc *q;
3048	struct tcf_chain *chain;
3049	struct tcf_block *block;
3050	unsigned long cl;
3051	int err;
3052
 
 
 
 
3053replay:
3054	q = NULL;
3055	err = nlmsg_parse_deprecated(n, sizeof(*t), tca, TCA_MAX,
3056				     rtm_tca_policy, extack);
3057	if (err < 0)
3058		return err;
3059
3060	t = nlmsg_data(n);
3061	parent = t->tcm_parent;
3062	cl = 0;
3063
3064	block = tcf_block_find(net, &q, &parent, &cl,
3065			       t->tcm_ifindex, t->tcm_block_index, extack);
3066	if (IS_ERR(block))
3067		return PTR_ERR(block);
3068
3069	chain_index = tca[TCA_CHAIN] ? nla_get_u32(tca[TCA_CHAIN]) : 0;
3070	if (chain_index > TC_ACT_EXT_VAL_MASK) {
3071		NL_SET_ERR_MSG(extack, "Specified chain index exceeds upper limit");
3072		err = -EINVAL;
3073		goto errout_block;
3074	}
3075
3076	mutex_lock(&block->lock);
3077	chain = tcf_chain_lookup(block, chain_index);
3078	if (n->nlmsg_type == RTM_NEWCHAIN) {
3079		if (chain) {
3080			if (tcf_chain_held_by_acts_only(chain)) {
3081				/* The chain exists only because there is
3082				 * some action referencing it.
3083				 */
3084				tcf_chain_hold(chain);
3085			} else {
3086				NL_SET_ERR_MSG(extack, "Filter chain already exists");
3087				err = -EEXIST;
3088				goto errout_block_locked;
3089			}
3090		} else {
3091			if (!(n->nlmsg_flags & NLM_F_CREATE)) {
3092				NL_SET_ERR_MSG(extack, "Need both RTM_NEWCHAIN and NLM_F_CREATE to create a new chain");
3093				err = -ENOENT;
3094				goto errout_block_locked;
3095			}
3096			chain = tcf_chain_create(block, chain_index);
3097			if (!chain) {
3098				NL_SET_ERR_MSG(extack, "Failed to create filter chain");
3099				err = -ENOMEM;
3100				goto errout_block_locked;
3101			}
3102		}
3103	} else {
3104		if (!chain || tcf_chain_held_by_acts_only(chain)) {
3105			NL_SET_ERR_MSG(extack, "Cannot find specified filter chain");
3106			err = -EINVAL;
3107			goto errout_block_locked;
3108		}
3109		tcf_chain_hold(chain);
3110	}
3111
3112	if (n->nlmsg_type == RTM_NEWCHAIN) {
3113		/* Modifying chain requires holding parent block lock. In case
3114		 * the chain was successfully added, take a reference to the
3115		 * chain. This ensures that an empty chain does not disappear at
3116		 * the end of this function.
3117		 */
3118		tcf_chain_hold(chain);
3119		chain->explicitly_created = true;
3120	}
3121	mutex_unlock(&block->lock);
3122
3123	switch (n->nlmsg_type) {
3124	case RTM_NEWCHAIN:
3125		err = tc_chain_tmplt_add(chain, net, tca, extack);
3126		if (err) {
3127			tcf_chain_put_explicitly_created(chain);
3128			goto errout;
3129		}
3130
3131		tc_chain_notify(chain, NULL, 0, NLM_F_CREATE | NLM_F_EXCL,
3132				RTM_NEWCHAIN, false, extack);
3133		break;
3134	case RTM_DELCHAIN:
3135		tfilter_notify_chain(net, skb, block, q, parent, n,
3136				     chain, RTM_DELTFILTER, extack);
3137		/* Flush the chain first as the user requested chain removal. */
3138		tcf_chain_flush(chain, true);
3139		/* In case the chain was successfully deleted, put a reference
3140		 * to the chain previously taken during addition.
3141		 */
3142		tcf_chain_put_explicitly_created(chain);
3143		break;
3144	case RTM_GETCHAIN:
3145		err = tc_chain_notify(chain, skb, n->nlmsg_seq,
3146				      n->nlmsg_flags, n->nlmsg_type, true, extack);
3147		if (err < 0)
3148			NL_SET_ERR_MSG(extack, "Failed to send chain notify message");
3149		break;
3150	default:
3151		err = -EOPNOTSUPP;
3152		NL_SET_ERR_MSG(extack, "Unsupported message type");
3153		goto errout;
3154	}
3155
3156errout:
3157	tcf_chain_put(chain);
3158errout_block:
3159	tcf_block_release(q, block, true);
3160	if (err == -EAGAIN)
3161		/* Replay the request. */
3162		goto replay;
3163	return err;
3164
3165errout_block_locked:
3166	mutex_unlock(&block->lock);
3167	goto errout_block;
3168}
3169
3170/* called with RTNL */
3171static int tc_dump_chain(struct sk_buff *skb, struct netlink_callback *cb)
3172{
3173	struct net *net = sock_net(skb->sk);
3174	struct nlattr *tca[TCA_MAX + 1];
3175	struct Qdisc *q = NULL;
3176	struct tcf_block *block;
3177	struct tcmsg *tcm = nlmsg_data(cb->nlh);
3178	struct tcf_chain *chain;
3179	long index_start;
3180	long index;
 
3181	int err;
3182
3183	if (nlmsg_len(cb->nlh) < sizeof(*tcm))
3184		return skb->len;
3185
3186	err = nlmsg_parse_deprecated(cb->nlh, sizeof(*tcm), tca, TCA_MAX,
3187				     rtm_tca_policy, cb->extack);
3188	if (err)
3189		return err;
3190
3191	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK) {
3192		block = tcf_block_refcnt_get(net, tcm->tcm_block_index);
3193		if (!block)
3194			goto out;
 
 
 
 
 
 
 
3195	} else {
3196		const struct Qdisc_class_ops *cops;
3197		struct net_device *dev;
3198		unsigned long cl = 0;
3199
3200		dev = __dev_get_by_index(net, tcm->tcm_ifindex);
3201		if (!dev)
3202			return skb->len;
3203
3204		if (!tcm->tcm_parent)
3205			q = rtnl_dereference(dev->qdisc);
3206		else
 
 
3207			q = qdisc_lookup(dev, TC_H_MAJ(tcm->tcm_parent));
3208
3209		if (!q)
3210			goto out;
3211		cops = q->ops->cl_ops;
3212		if (!cops)
3213			goto out;
3214		if (!cops->tcf_block)
3215			goto out;
3216		if (TC_H_MIN(tcm->tcm_parent)) {
3217			cl = cops->find(q, tcm->tcm_parent);
3218			if (cl == 0)
3219				goto out;
3220		}
3221		block = cops->tcf_block(q, cl, NULL);
3222		if (!block)
3223			goto out;
3224		if (tcf_block_shared(block))
3225			q = NULL;
3226	}
3227
3228	index_start = cb->args[0];
3229	index = 0;
3230
3231	mutex_lock(&block->lock);
3232	list_for_each_entry(chain, &block->chain_list, list) {
3233		if ((tca[TCA_CHAIN] &&
3234		     nla_get_u32(tca[TCA_CHAIN]) != chain->index))
3235			continue;
3236		if (index < index_start) {
3237			index++;
3238			continue;
3239		}
3240		if (tcf_chain_held_by_acts_only(chain))
3241			continue;
3242		err = tc_chain_fill_node(chain->tmplt_ops, chain->tmplt_priv,
3243					 chain->index, net, skb, block,
3244					 NETLINK_CB(cb->skb).portid,
3245					 cb->nlh->nlmsg_seq, NLM_F_MULTI,
3246					 RTM_NEWCHAIN, NULL);
3247		if (err <= 0)
3248			break;
3249		index++;
3250	}
3251	mutex_unlock(&block->lock);
3252
3253	if (tcm->tcm_ifindex == TCM_IFINDEX_MAGIC_BLOCK)
3254		tcf_block_refcnt_put(block, true);
3255	cb->args[0] = index;
3256
3257out:
3258	/* If we did no progress, the error (EMSGSIZE) is real */
3259	if (skb->len == 0 && err)
3260		return err;
3261	return skb->len;
3262}
3263
3264int tcf_exts_init_ex(struct tcf_exts *exts, struct net *net, int action,
3265		     int police, struct tcf_proto *tp, u32 handle,
3266		     bool use_action_miss)
3267{
3268	int err = 0;
3269
3270#ifdef CONFIG_NET_CLS_ACT
3271	exts->type = 0;
3272	exts->nr_actions = 0;
3273	exts->miss_cookie_node = NULL;
3274	/* Note: we do not own yet a reference on net.
3275	 * This reference might be taken later from tcf_exts_get_net().
3276	 */
3277	exts->net = net;
3278	exts->actions = kcalloc(TCA_ACT_MAX_PRIO, sizeof(struct tc_action *),
3279				GFP_KERNEL);
3280	if (!exts->actions)
3281		return -ENOMEM;
3282#endif
3283
3284	exts->action = action;
3285	exts->police = police;
3286
3287	if (!use_action_miss)
3288		return 0;
3289
3290	err = tcf_exts_miss_cookie_base_alloc(exts, tp, handle);
3291	if (err)
3292		goto err_miss_alloc;
3293
3294	return 0;
3295
3296err_miss_alloc:
3297	tcf_exts_destroy(exts);
3298#ifdef CONFIG_NET_CLS_ACT
3299	exts->actions = NULL;
3300#endif
3301	return err;
3302}
3303EXPORT_SYMBOL(tcf_exts_init_ex);
3304
3305void tcf_exts_destroy(struct tcf_exts *exts)
3306{
3307	tcf_exts_miss_cookie_base_destroy(exts);
3308
3309#ifdef CONFIG_NET_CLS_ACT
3310	if (exts->actions) {
3311		tcf_action_destroy(exts->actions, TCA_ACT_UNBIND);
3312		kfree(exts->actions);
3313	}
3314	exts->nr_actions = 0;
3315#endif
3316}
3317EXPORT_SYMBOL(tcf_exts_destroy);
3318
3319int tcf_exts_validate_ex(struct net *net, struct tcf_proto *tp, struct nlattr **tb,
3320			 struct nlattr *rate_tlv, struct tcf_exts *exts,
3321			 u32 flags, u32 fl_flags, struct netlink_ext_ack *extack)
3322{
3323#ifdef CONFIG_NET_CLS_ACT
3324	{
3325		int init_res[TCA_ACT_MAX_PRIO] = {};
3326		struct tc_action *act;
3327		size_t attr_size = 0;
3328
3329		if (exts->police && tb[exts->police]) {
3330			struct tc_action_ops *a_o;
3331
3332			flags |= TCA_ACT_FLAGS_POLICE | TCA_ACT_FLAGS_BIND;
3333			a_o = tc_action_load_ops(tb[exts->police], flags,
3334						 extack);
3335			if (IS_ERR(a_o))
3336				return PTR_ERR(a_o);
3337			act = tcf_action_init_1(net, tp, tb[exts->police],
3338						rate_tlv, a_o, init_res, flags,
 
3339						extack);
3340			module_put(a_o->owner);
3341			if (IS_ERR(act))
3342				return PTR_ERR(act);
3343
3344			act->type = exts->type = TCA_OLD_COMPAT;
3345			exts->actions[0] = act;
3346			exts->nr_actions = 1;
3347			tcf_idr_insert_many(exts->actions, init_res);
3348		} else if (exts->action && tb[exts->action]) {
3349			int err;
3350
3351			flags |= TCA_ACT_FLAGS_BIND;
3352			err = tcf_action_init(net, tp, tb[exts->action],
3353					      rate_tlv, exts->actions, init_res,
3354					      &attr_size, flags, fl_flags,
3355					      extack);
3356			if (err < 0)
3357				return err;
3358			exts->nr_actions = err;
3359		}
3360	}
3361#else
3362	if ((exts->action && tb[exts->action]) ||
3363	    (exts->police && tb[exts->police])) {
3364		NL_SET_ERR_MSG(extack, "Classifier actions are not supported per compile options (CONFIG_NET_CLS_ACT)");
3365		return -EOPNOTSUPP;
3366	}
3367#endif
3368
3369	return 0;
3370}
3371EXPORT_SYMBOL(tcf_exts_validate_ex);
3372
3373int tcf_exts_validate(struct net *net, struct tcf_proto *tp, struct nlattr **tb,
3374		      struct nlattr *rate_tlv, struct tcf_exts *exts,
3375		      u32 flags, struct netlink_ext_ack *extack)
3376{
3377	return tcf_exts_validate_ex(net, tp, tb, rate_tlv, exts,
3378				    flags, 0, extack);
3379}
3380EXPORT_SYMBOL(tcf_exts_validate);
3381
3382void tcf_exts_change(struct tcf_exts *dst, struct tcf_exts *src)
3383{
3384#ifdef CONFIG_NET_CLS_ACT
3385	struct tcf_exts old = *dst;
3386
3387	*dst = *src;
3388	tcf_exts_destroy(&old);
3389#endif
3390}
3391EXPORT_SYMBOL(tcf_exts_change);
3392
3393#ifdef CONFIG_NET_CLS_ACT
3394static struct tc_action *tcf_exts_first_act(struct tcf_exts *exts)
3395{
3396	if (exts->nr_actions == 0)
3397		return NULL;
3398	else
3399		return exts->actions[0];
3400}
3401#endif
3402
3403int tcf_exts_dump(struct sk_buff *skb, struct tcf_exts *exts)
3404{
3405#ifdef CONFIG_NET_CLS_ACT
3406	struct nlattr *nest;
3407
3408	if (exts->action && tcf_exts_has_actions(exts)) {
3409		/*
3410		 * again for backward compatible mode - we want
3411		 * to work with both old and new modes of entering
3412		 * tc data even if iproute2  was newer - jhs
3413		 */
3414		if (exts->type != TCA_OLD_COMPAT) {
3415			nest = nla_nest_start_noflag(skb, exts->action);
3416			if (nest == NULL)
3417				goto nla_put_failure;
3418
3419			if (tcf_action_dump(skb, exts->actions, 0, 0, false)
3420			    < 0)
3421				goto nla_put_failure;
3422			nla_nest_end(skb, nest);
3423		} else if (exts->police) {
3424			struct tc_action *act = tcf_exts_first_act(exts);
3425			nest = nla_nest_start_noflag(skb, exts->police);
3426			if (nest == NULL || !act)
3427				goto nla_put_failure;
3428			if (tcf_action_dump_old(skb, act, 0, 0) < 0)
3429				goto nla_put_failure;
3430			nla_nest_end(skb, nest);
3431		}
3432	}
3433	return 0;
3434
3435nla_put_failure:
3436	nla_nest_cancel(skb, nest);
3437	return -1;
3438#else
3439	return 0;
3440#endif
3441}
3442EXPORT_SYMBOL(tcf_exts_dump);
3443
3444int tcf_exts_terse_dump(struct sk_buff *skb, struct tcf_exts *exts)
3445{
3446#ifdef CONFIG_NET_CLS_ACT
3447	struct nlattr *nest;
3448
3449	if (!exts->action || !tcf_exts_has_actions(exts))
3450		return 0;
3451
3452	nest = nla_nest_start_noflag(skb, exts->action);
3453	if (!nest)
3454		goto nla_put_failure;
3455
3456	if (tcf_action_dump(skb, exts->actions, 0, 0, true) < 0)
3457		goto nla_put_failure;
3458	nla_nest_end(skb, nest);
3459	return 0;
3460
3461nla_put_failure:
3462	nla_nest_cancel(skb, nest);
3463	return -1;
3464#else
3465	return 0;
3466#endif
3467}
3468EXPORT_SYMBOL(tcf_exts_terse_dump);
3469
3470int tcf_exts_dump_stats(struct sk_buff *skb, struct tcf_exts *exts)
3471{
3472#ifdef CONFIG_NET_CLS_ACT
3473	struct tc_action *a = tcf_exts_first_act(exts);
3474	if (a != NULL && tcf_action_copy_stats(skb, a, 1) < 0)
3475		return -1;
3476#endif
3477	return 0;
3478}
3479EXPORT_SYMBOL(tcf_exts_dump_stats);
3480
3481static void tcf_block_offload_inc(struct tcf_block *block, u32 *flags)
3482{
3483	if (*flags & TCA_CLS_FLAGS_IN_HW)
3484		return;
3485	*flags |= TCA_CLS_FLAGS_IN_HW;
3486	atomic_inc(&block->offloadcnt);
3487}
3488
3489static void tcf_block_offload_dec(struct tcf_block *block, u32 *flags)
3490{
3491	if (!(*flags & TCA_CLS_FLAGS_IN_HW))
3492		return;
3493	*flags &= ~TCA_CLS_FLAGS_IN_HW;
3494	atomic_dec(&block->offloadcnt);
3495}
3496
3497static void tc_cls_offload_cnt_update(struct tcf_block *block,
3498				      struct tcf_proto *tp, u32 *cnt,
3499				      u32 *flags, u32 diff, bool add)
3500{
3501	lockdep_assert_held(&block->cb_lock);
3502
3503	spin_lock(&tp->lock);
3504	if (add) {
3505		if (!*cnt)
3506			tcf_block_offload_inc(block, flags);
3507		*cnt += diff;
3508	} else {
3509		*cnt -= diff;
3510		if (!*cnt)
3511			tcf_block_offload_dec(block, flags);
3512	}
3513	spin_unlock(&tp->lock);
3514}
3515
3516static void
3517tc_cls_offload_cnt_reset(struct tcf_block *block, struct tcf_proto *tp,
3518			 u32 *cnt, u32 *flags)
3519{
3520	lockdep_assert_held(&block->cb_lock);
3521
3522	spin_lock(&tp->lock);
3523	tcf_block_offload_dec(block, flags);
3524	*cnt = 0;
3525	spin_unlock(&tp->lock);
3526}
3527
3528static int
3529__tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type,
3530		   void *type_data, bool err_stop)
3531{
3532	struct flow_block_cb *block_cb;
3533	int ok_count = 0;
3534	int err;
3535
3536	list_for_each_entry(block_cb, &block->flow_block.cb_list, list) {
3537		err = block_cb->cb(type, type_data, block_cb->cb_priv);
3538		if (err) {
3539			if (err_stop)
3540				return err;
3541		} else {
3542			ok_count++;
3543		}
3544	}
3545	return ok_count;
3546}
3547
3548int tc_setup_cb_call(struct tcf_block *block, enum tc_setup_type type,
3549		     void *type_data, bool err_stop, bool rtnl_held)
3550{
3551	bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3552	int ok_count;
3553
3554retry:
3555	if (take_rtnl)
3556		rtnl_lock();
3557	down_read(&block->cb_lock);
3558	/* Need to obtain rtnl lock if block is bound to devs that require it.
3559	 * In block bind code cb_lock is obtained while holding rtnl, so we must
3560	 * obtain the locks in same order here.
3561	 */
3562	if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3563		up_read(&block->cb_lock);
3564		take_rtnl = true;
3565		goto retry;
3566	}
3567
3568	ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3569
3570	up_read(&block->cb_lock);
3571	if (take_rtnl)
3572		rtnl_unlock();
3573	return ok_count;
3574}
3575EXPORT_SYMBOL(tc_setup_cb_call);
3576
3577/* Non-destructive filter add. If filter that wasn't already in hardware is
3578 * successfully offloaded, increment block offloads counter. On failure,
3579 * previously offloaded filter is considered to be intact and offloads counter
3580 * is not decremented.
3581 */
3582
3583int tc_setup_cb_add(struct tcf_block *block, struct tcf_proto *tp,
3584		    enum tc_setup_type type, void *type_data, bool err_stop,
3585		    u32 *flags, unsigned int *in_hw_count, bool rtnl_held)
3586{
3587	bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3588	int ok_count;
3589
3590retry:
3591	if (take_rtnl)
3592		rtnl_lock();
3593	down_read(&block->cb_lock);
3594	/* Need to obtain rtnl lock if block is bound to devs that require it.
3595	 * In block bind code cb_lock is obtained while holding rtnl, so we must
3596	 * obtain the locks in same order here.
3597	 */
3598	if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3599		up_read(&block->cb_lock);
3600		take_rtnl = true;
3601		goto retry;
3602	}
3603
3604	/* Make sure all netdevs sharing this block are offload-capable. */
3605	if (block->nooffloaddevcnt && err_stop) {
3606		ok_count = -EOPNOTSUPP;
3607		goto err_unlock;
3608	}
3609
3610	ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3611	if (ok_count < 0)
3612		goto err_unlock;
3613
3614	if (tp->ops->hw_add)
3615		tp->ops->hw_add(tp, type_data);
3616	if (ok_count > 0)
3617		tc_cls_offload_cnt_update(block, tp, in_hw_count, flags,
3618					  ok_count, true);
3619err_unlock:
3620	up_read(&block->cb_lock);
3621	if (take_rtnl)
3622		rtnl_unlock();
3623	return min(ok_count, 0);
3624}
3625EXPORT_SYMBOL(tc_setup_cb_add);
3626
3627/* Destructive filter replace. If filter that wasn't already in hardware is
3628 * successfully offloaded, increment block offload counter. On failure,
3629 * previously offloaded filter is considered to be destroyed and offload counter
3630 * is decremented.
3631 */
3632
3633int tc_setup_cb_replace(struct tcf_block *block, struct tcf_proto *tp,
3634			enum tc_setup_type type, void *type_data, bool err_stop,
3635			u32 *old_flags, unsigned int *old_in_hw_count,
3636			u32 *new_flags, unsigned int *new_in_hw_count,
3637			bool rtnl_held)
3638{
3639	bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3640	int ok_count;
3641
3642retry:
3643	if (take_rtnl)
3644		rtnl_lock();
3645	down_read(&block->cb_lock);
3646	/* Need to obtain rtnl lock if block is bound to devs that require it.
3647	 * In block bind code cb_lock is obtained while holding rtnl, so we must
3648	 * obtain the locks in same order here.
3649	 */
3650	if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3651		up_read(&block->cb_lock);
3652		take_rtnl = true;
3653		goto retry;
3654	}
3655
3656	/* Make sure all netdevs sharing this block are offload-capable. */
3657	if (block->nooffloaddevcnt && err_stop) {
3658		ok_count = -EOPNOTSUPP;
3659		goto err_unlock;
3660	}
3661
3662	tc_cls_offload_cnt_reset(block, tp, old_in_hw_count, old_flags);
3663	if (tp->ops->hw_del)
3664		tp->ops->hw_del(tp, type_data);
3665
3666	ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3667	if (ok_count < 0)
3668		goto err_unlock;
3669
3670	if (tp->ops->hw_add)
3671		tp->ops->hw_add(tp, type_data);
3672	if (ok_count > 0)
3673		tc_cls_offload_cnt_update(block, tp, new_in_hw_count,
3674					  new_flags, ok_count, true);
3675err_unlock:
3676	up_read(&block->cb_lock);
3677	if (take_rtnl)
3678		rtnl_unlock();
3679	return min(ok_count, 0);
3680}
3681EXPORT_SYMBOL(tc_setup_cb_replace);
3682
3683/* Destroy filter and decrement block offload counter, if filter was previously
3684 * offloaded.
3685 */
3686
3687int tc_setup_cb_destroy(struct tcf_block *block, struct tcf_proto *tp,
3688			enum tc_setup_type type, void *type_data, bool err_stop,
3689			u32 *flags, unsigned int *in_hw_count, bool rtnl_held)
3690{
3691	bool take_rtnl = READ_ONCE(block->lockeddevcnt) && !rtnl_held;
3692	int ok_count;
3693
3694retry:
3695	if (take_rtnl)
3696		rtnl_lock();
3697	down_read(&block->cb_lock);
3698	/* Need to obtain rtnl lock if block is bound to devs that require it.
3699	 * In block bind code cb_lock is obtained while holding rtnl, so we must
3700	 * obtain the locks in same order here.
3701	 */
3702	if (!rtnl_held && !take_rtnl && block->lockeddevcnt) {
3703		up_read(&block->cb_lock);
3704		take_rtnl = true;
3705		goto retry;
3706	}
3707
3708	ok_count = __tc_setup_cb_call(block, type, type_data, err_stop);
3709
3710	tc_cls_offload_cnt_reset(block, tp, in_hw_count, flags);
3711	if (tp->ops->hw_del)
3712		tp->ops->hw_del(tp, type_data);
3713
3714	up_read(&block->cb_lock);
3715	if (take_rtnl)
3716		rtnl_unlock();
3717	return min(ok_count, 0);
3718}
3719EXPORT_SYMBOL(tc_setup_cb_destroy);
3720
3721int tc_setup_cb_reoffload(struct tcf_block *block, struct tcf_proto *tp,
3722			  bool add, flow_setup_cb_t *cb,
3723			  enum tc_setup_type type, void *type_data,
3724			  void *cb_priv, u32 *flags, unsigned int *in_hw_count)
3725{
3726	int err = cb(type, type_data, cb_priv);
3727
3728	if (err) {
3729		if (add && tc_skip_sw(*flags))
3730			return err;
3731	} else {
3732		tc_cls_offload_cnt_update(block, tp, in_hw_count, flags, 1,
3733					  add);
3734	}
3735
3736	return 0;
3737}
3738EXPORT_SYMBOL(tc_setup_cb_reoffload);
3739
3740static int tcf_act_get_user_cookie(struct flow_action_entry *entry,
3741				   const struct tc_action *act)
3742{
3743	struct tc_cookie *user_cookie;
3744	int err = 0;
3745
3746	rcu_read_lock();
3747	user_cookie = rcu_dereference(act->user_cookie);
3748	if (user_cookie) {
3749		entry->user_cookie = flow_action_cookie_create(user_cookie->data,
3750							       user_cookie->len,
3751							       GFP_ATOMIC);
3752		if (!entry->user_cookie)
3753			err = -ENOMEM;
3754	}
3755	rcu_read_unlock();
3756	return err;
3757}
 
3758
3759static void tcf_act_put_user_cookie(struct flow_action_entry *entry)
 
3760{
3761	flow_action_cookie_destroy(entry->user_cookie);
 
 
 
 
 
3762}
3763
3764void tc_cleanup_offload_action(struct flow_action *flow_action)
3765{
3766	struct flow_action_entry *entry;
3767	int i;
 
 
3768
3769	flow_action_for_each(i, entry, flow_action) {
3770		tcf_act_put_user_cookie(entry);
3771		if (entry->destructor)
3772			entry->destructor(entry->destructor_priv);
3773	}
 
 
 
 
3774}
3775EXPORT_SYMBOL(tc_cleanup_offload_action);
3776
3777static int tc_setup_offload_act(struct tc_action *act,
3778				struct flow_action_entry *entry,
3779				u32 *index_inc,
3780				struct netlink_ext_ack *extack)
3781{
3782#ifdef CONFIG_NET_CLS_ACT
3783	if (act->ops->offload_act_setup) {
3784		return act->ops->offload_act_setup(act, entry, index_inc, true,
3785						   extack);
3786	} else {
3787		NL_SET_ERR_MSG(extack, "Action does not support offload");
3788		return -EOPNOTSUPP;
3789	}
3790#else
3791	return 0;
3792#endif
3793}
3794
3795int tc_setup_action(struct flow_action *flow_action,
3796		    struct tc_action *actions[],
3797		    u32 miss_cookie_base,
3798		    struct netlink_ext_ack *extack)
3799{
3800	int i, j, k, index, err = 0;
3801	struct tc_action *act;
3802
3803	BUILD_BUG_ON(TCA_ACT_HW_STATS_ANY != FLOW_ACTION_HW_STATS_ANY);
3804	BUILD_BUG_ON(TCA_ACT_HW_STATS_IMMEDIATE != FLOW_ACTION_HW_STATS_IMMEDIATE);
3805	BUILD_BUG_ON(TCA_ACT_HW_STATS_DELAYED != FLOW_ACTION_HW_STATS_DELAYED);
3806
3807	if (!actions)
3808		return 0;
3809
3810	j = 0;
3811	tcf_act_for_each_action(i, act, actions) {
3812		struct flow_action_entry *entry;
3813
3814		entry = &flow_action->entries[j];
3815		spin_lock_bh(&act->tcfa_lock);
3816		err = tcf_act_get_user_cookie(entry, act);
3817		if (err)
3818			goto err_out_locked;
3819
3820		index = 0;
3821		err = tc_setup_offload_act(act, entry, &index, extack);
3822		if (err)
3823			goto err_out_locked;
3824
3825		for (k = 0; k < index ; k++) {
3826			entry[k].hw_stats = tc_act_hw_stats(act->hw_stats);
3827			entry[k].hw_index = act->tcfa_index;
3828			entry[k].cookie = (unsigned long)act;
3829			entry[k].miss_cookie =
3830				tcf_exts_miss_cookie_get(miss_cookie_base, i);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3831		}
3832
3833		j += index;
3834
3835		spin_unlock_bh(&act->tcfa_lock);
3836	}
3837
3838err_out:
 
 
 
3839	if (err)
3840		tc_cleanup_offload_action(flow_action);
3841
3842	return err;
3843err_out_locked:
3844	spin_unlock_bh(&act->tcfa_lock);
3845	goto err_out;
3846}
3847
3848int tc_setup_offload_action(struct flow_action *flow_action,
3849			    const struct tcf_exts *exts,
3850			    struct netlink_ext_ack *extack)
3851{
3852#ifdef CONFIG_NET_CLS_ACT
3853	u32 miss_cookie_base;
3854
3855	if (!exts)
3856		return 0;
3857
3858	miss_cookie_base = exts->miss_cookie_node ?
3859			   exts->miss_cookie_node->miss_cookie_base : 0;
3860	return tc_setup_action(flow_action, exts->actions, miss_cookie_base,
3861			       extack);
3862#else
3863	return 0;
3864#endif
3865}
3866EXPORT_SYMBOL(tc_setup_offload_action);
3867
3868unsigned int tcf_exts_num_actions(struct tcf_exts *exts)
3869{
3870	unsigned int num_acts = 0;
3871	struct tc_action *act;
3872	int i;
3873
3874	tcf_exts_for_each_action(i, act, exts) {
3875		if (is_tcf_pedit(act))
3876			num_acts += tcf_pedit_nkeys(act);
3877		else
3878			num_acts++;
3879	}
3880	return num_acts;
3881}
3882EXPORT_SYMBOL(tcf_exts_num_actions);
3883
3884#ifdef CONFIG_NET_CLS_ACT
3885static int tcf_qevent_parse_block_index(struct nlattr *block_index_attr,
3886					u32 *p_block_index,
3887					struct netlink_ext_ack *extack)
3888{
3889	*p_block_index = nla_get_u32(block_index_attr);
3890	if (!*p_block_index) {
3891		NL_SET_ERR_MSG(extack, "Block number may not be zero");
3892		return -EINVAL;
3893	}
3894
3895	return 0;
3896}
3897
3898int tcf_qevent_init(struct tcf_qevent *qe, struct Qdisc *sch,
3899		    enum flow_block_binder_type binder_type,
3900		    struct nlattr *block_index_attr,
3901		    struct netlink_ext_ack *extack)
3902{
3903	u32 block_index;
3904	int err;
3905
3906	if (!block_index_attr)
3907		return 0;
3908
3909	err = tcf_qevent_parse_block_index(block_index_attr, &block_index, extack);
3910	if (err)
3911		return err;
3912
3913	qe->info.binder_type = binder_type;
3914	qe->info.chain_head_change = tcf_chain_head_change_dflt;
3915	qe->info.chain_head_change_priv = &qe->filter_chain;
3916	qe->info.block_index = block_index;
3917
3918	return tcf_block_get_ext(&qe->block, sch, &qe->info, extack);
3919}
3920EXPORT_SYMBOL(tcf_qevent_init);
3921
3922void tcf_qevent_destroy(struct tcf_qevent *qe, struct Qdisc *sch)
3923{
3924	if (qe->info.block_index)
3925		tcf_block_put_ext(qe->block, sch, &qe->info);
3926}
3927EXPORT_SYMBOL(tcf_qevent_destroy);
3928
3929int tcf_qevent_validate_change(struct tcf_qevent *qe, struct nlattr *block_index_attr,
3930			       struct netlink_ext_ack *extack)
3931{
3932	u32 block_index;
3933	int err;
3934
3935	if (!block_index_attr)
3936		return 0;
3937
3938	err = tcf_qevent_parse_block_index(block_index_attr, &block_index, extack);
3939	if (err)
3940		return err;
3941
3942	/* Bounce newly-configured block or change in block. */
3943	if (block_index != qe->info.block_index) {
3944		NL_SET_ERR_MSG(extack, "Change of blocks is not supported");
3945		return -EINVAL;
3946	}
3947
3948	return 0;
3949}
3950EXPORT_SYMBOL(tcf_qevent_validate_change);
3951
3952struct sk_buff *tcf_qevent_handle(struct tcf_qevent *qe, struct Qdisc *sch, struct sk_buff *skb,
3953				  struct sk_buff **to_free, int *ret)
3954{
3955	struct tcf_result cl_res;
3956	struct tcf_proto *fl;
3957
3958	if (!qe->info.block_index)
3959		return skb;
3960
3961	fl = rcu_dereference_bh(qe->filter_chain);
3962
3963	switch (tcf_classify(skb, NULL, fl, &cl_res, false)) {
3964	case TC_ACT_SHOT:
3965		qdisc_qstats_drop(sch);
3966		__qdisc_drop(skb, to_free);
3967		*ret = __NET_XMIT_BYPASS;
3968		return NULL;
3969	case TC_ACT_STOLEN:
3970	case TC_ACT_QUEUED:
3971	case TC_ACT_TRAP:
3972		__qdisc_drop(skb, to_free);
3973		*ret = __NET_XMIT_STOLEN;
3974		return NULL;
3975	case TC_ACT_REDIRECT:
3976		skb_do_redirect(skb);
3977		*ret = __NET_XMIT_STOLEN;
3978		return NULL;
3979	}
3980
3981	return skb;
3982}
3983EXPORT_SYMBOL(tcf_qevent_handle);
3984
3985int tcf_qevent_dump(struct sk_buff *skb, int attr_name, struct tcf_qevent *qe)
3986{
3987	if (!qe->info.block_index)
3988		return 0;
3989	return nla_put_u32(skb, attr_name, qe->info.block_index);
3990}
3991EXPORT_SYMBOL(tcf_qevent_dump);
3992#endif
3993
3994static __net_init int tcf_net_init(struct net *net)
3995{
3996	struct tcf_net *tn = net_generic(net, tcf_net_id);
3997
3998	spin_lock_init(&tn->idr_lock);
3999	idr_init(&tn->idr);
4000	return 0;
4001}
4002
4003static void __net_exit tcf_net_exit(struct net *net)
4004{
4005	struct tcf_net *tn = net_generic(net, tcf_net_id);
4006
4007	idr_destroy(&tn->idr);
4008}
4009
4010static struct pernet_operations tcf_net_ops = {
4011	.init = tcf_net_init,
4012	.exit = tcf_net_exit,
4013	.id   = &tcf_net_id,
4014	.size = sizeof(struct tcf_net),
4015};
4016
 
 
 
 
 
4017static int __init tc_filter_init(void)
4018{
4019	int err;
4020
4021	tc_filter_wq = alloc_ordered_workqueue("tc_filter_workqueue", 0);
4022	if (!tc_filter_wq)
4023		return -ENOMEM;
4024
4025	err = register_pernet_subsys(&tcf_net_ops);
4026	if (err)
4027		goto err_register_pernet_subsys;
4028
4029	xa_init_flags(&tcf_exts_miss_cookies_xa, XA_FLAGS_ALLOC1);
4030
4031	rtnl_register(PF_UNSPEC, RTM_NEWTFILTER, tc_new_tfilter, NULL,
4032		      RTNL_FLAG_DOIT_UNLOCKED);
4033	rtnl_register(PF_UNSPEC, RTM_DELTFILTER, tc_del_tfilter, NULL,
4034		      RTNL_FLAG_DOIT_UNLOCKED);
4035	rtnl_register(PF_UNSPEC, RTM_GETTFILTER, tc_get_tfilter,
4036		      tc_dump_tfilter, RTNL_FLAG_DOIT_UNLOCKED);
4037	rtnl_register(PF_UNSPEC, RTM_NEWCHAIN, tc_ctl_chain, NULL, 0);
4038	rtnl_register(PF_UNSPEC, RTM_DELCHAIN, tc_ctl_chain, NULL, 0);
4039	rtnl_register(PF_UNSPEC, RTM_GETCHAIN, tc_ctl_chain,
4040		      tc_dump_chain, 0);
4041
4042	return 0;
4043
4044err_register_pernet_subsys:
4045	destroy_workqueue(tc_filter_wq);
4046	return err;
4047}
4048
4049subsys_initcall(tc_filter_init);