xref: /linux/net/sched/act_api.c (revision d7b4e3287ca3a7baf66efd9158498e551a9550da)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * net/sched/act_api.c	Packet action API.
4  *
5  * Author:	Jamal Hadi Salim
6  */
7 
8 #include <linux/types.h>
9 #include <linux/kernel.h>
10 #include <linux/string.h>
11 #include <linux/errno.h>
12 #include <linux/slab.h>
13 #include <linux/skbuff.h>
14 #include <linux/init.h>
15 #include <linux/kmod.h>
16 #include <linux/err.h>
17 #include <linux/module.h>
18 #include <net/net_namespace.h>
19 #include <net/sock.h>
20 #include <net/sch_generic.h>
21 #include <net/pkt_cls.h>
22 #include <net/tc_act/tc_pedit.h>
23 #include <net/act_api.h>
24 #include <net/netlink.h>
25 #include <net/flow_offload.h>
26 #include <net/tc_wrapper.h>
27 
28 #ifdef CONFIG_INET
29 DEFINE_STATIC_KEY_FALSE(tcf_frag_xmit_count);
30 EXPORT_SYMBOL_GPL(tcf_frag_xmit_count);
31 #endif
32 
33 int tcf_dev_queue_xmit(struct sk_buff *skb, int (*xmit)(struct sk_buff *skb))
34 {
35 #ifdef CONFIG_INET
36 	if (static_branch_unlikely(&tcf_frag_xmit_count))
37 		return sch_frag_xmit_hook(skb, xmit);
38 #endif
39 
40 	return xmit(skb);
41 }
42 EXPORT_SYMBOL_GPL(tcf_dev_queue_xmit);
43 
44 static void tcf_action_goto_chain_exec(const struct tc_action *a,
45 				       struct tcf_result *res)
46 {
47 	const struct tcf_chain *chain = rcu_dereference_bh(a->goto_chain);
48 
49 	res->goto_tp = rcu_dereference_bh(chain->filter_chain);
50 }
51 
52 static void tcf_free_cookie_rcu(struct rcu_head *p)
53 {
54 	struct tc_cookie *cookie = container_of(p, struct tc_cookie, rcu);
55 
56 	kfree(cookie->data);
57 	kfree(cookie);
58 }
59 
60 static void tcf_set_action_cookie(struct tc_cookie __rcu **old_cookie,
61 				  struct tc_cookie *new_cookie)
62 {
63 	struct tc_cookie *old;
64 
65 	old = xchg((__force struct tc_cookie **)old_cookie, new_cookie);
66 	if (old)
67 		call_rcu(&old->rcu, tcf_free_cookie_rcu);
68 }
69 
70 int tcf_action_check_ctrlact(int action, struct tcf_proto *tp,
71 			     struct tcf_chain **newchain,
72 			     struct netlink_ext_ack *extack)
73 {
74 	int opcode = TC_ACT_EXT_OPCODE(action), ret = -EINVAL;
75 	u32 chain_index;
76 
77 	if (!opcode)
78 		ret = action > TC_ACT_VALUE_MAX ? -EINVAL : 0;
79 	else if (opcode <= TC_ACT_EXT_OPCODE_MAX || action == TC_ACT_UNSPEC)
80 		ret = 0;
81 	if (ret) {
82 		NL_SET_ERR_MSG(extack, "invalid control action");
83 		goto end;
84 	}
85 
86 	if (TC_ACT_EXT_CMP(action, TC_ACT_GOTO_CHAIN)) {
87 		chain_index = action & TC_ACT_EXT_VAL_MASK;
88 		if (!tp || !newchain) {
89 			ret = -EINVAL;
90 			NL_SET_ERR_MSG(extack,
91 				       "can't goto NULL proto/chain");
92 			goto end;
93 		}
94 		*newchain = tcf_chain_get_by_act(tp->chain->block, chain_index);
95 		if (!*newchain) {
96 			ret = -ENOMEM;
97 			NL_SET_ERR_MSG(extack,
98 				       "can't allocate goto_chain");
99 		}
100 	}
101 end:
102 	return ret;
103 }
104 EXPORT_SYMBOL(tcf_action_check_ctrlact);
105 
106 struct tcf_chain *tcf_action_set_ctrlact(struct tc_action *a, int action,
107 					 struct tcf_chain *goto_chain)
108 {
109 	a->tcfa_action = action;
110 	goto_chain = rcu_replace_pointer(a->goto_chain, goto_chain, 1);
111 	return goto_chain;
112 }
113 EXPORT_SYMBOL(tcf_action_set_ctrlact);
114 
115 /* XXX: For standalone actions, we don't need a RCU grace period either, because
116  * actions are always connected to filters and filters are already destroyed in
117  * RCU callbacks, so after a RCU grace period actions are already disconnected
118  * from filters. Readers later can not find us.
119  */
120 static void free_tcf(struct tc_action *p)
121 {
122 	struct tcf_chain *chain = rcu_dereference_protected(p->goto_chain, 1);
123 
124 	free_percpu(p->cpu_bstats);
125 	free_percpu(p->cpu_bstats_hw);
126 	free_percpu(p->cpu_qstats);
127 
128 	tcf_set_action_cookie(&p->user_cookie, NULL);
129 	if (chain)
130 		tcf_chain_put_by_act(chain);
131 
132 	kfree(p);
133 }
134 
135 static void offload_action_hw_count_set(struct tc_action *act,
136 					u32 hw_count)
137 {
138 	act->in_hw_count = hw_count;
139 }
140 
141 static void offload_action_hw_count_inc(struct tc_action *act,
142 					u32 hw_count)
143 {
144 	act->in_hw_count += hw_count;
145 }
146 
147 static void offload_action_hw_count_dec(struct tc_action *act,
148 					u32 hw_count)
149 {
150 	act->in_hw_count = act->in_hw_count > hw_count ?
151 			   act->in_hw_count - hw_count : 0;
152 }
153 
154 static unsigned int tcf_offload_act_num_actions_single(struct tc_action *act)
155 {
156 	if (is_tcf_pedit(act))
157 		return tcf_pedit_nkeys(act);
158 	else
159 		return 1;
160 }
161 
162 static bool tc_act_skip_hw(u32 flags)
163 {
164 	return (flags & TCA_ACT_FLAGS_SKIP_HW) ? true : false;
165 }
166 
167 static bool tc_act_skip_sw(u32 flags)
168 {
169 	return (flags & TCA_ACT_FLAGS_SKIP_SW) ? true : false;
170 }
171 
172 /* SKIP_HW and SKIP_SW are mutually exclusive flags. */
173 static bool tc_act_flags_valid(u32 flags)
174 {
175 	flags &= TCA_ACT_FLAGS_SKIP_HW | TCA_ACT_FLAGS_SKIP_SW;
176 
177 	return flags ^ (TCA_ACT_FLAGS_SKIP_HW | TCA_ACT_FLAGS_SKIP_SW);
178 }
179 
180 static int offload_action_init(struct flow_offload_action *fl_action,
181 			       struct tc_action *act,
182 			       enum offload_act_command  cmd,
183 			       struct netlink_ext_ack *extack)
184 {
185 	int err;
186 
187 	fl_action->extack = extack;
188 	fl_action->command = cmd;
189 	fl_action->index = act->tcfa_index;
190 	fl_action->cookie = (unsigned long)act;
191 
192 	if (act->ops->offload_act_setup) {
193 		spin_lock_bh(&act->tcfa_lock);
194 		err = act->ops->offload_act_setup(act, fl_action, NULL,
195 						  false, extack);
196 		spin_unlock_bh(&act->tcfa_lock);
197 		return err;
198 	}
199 
200 	return -EOPNOTSUPP;
201 }
202 
203 static int tcf_action_offload_cmd_ex(struct flow_offload_action *fl_act,
204 				     u32 *hw_count)
205 {
206 	int err;
207 
208 	err = flow_indr_dev_setup_offload(NULL, NULL, TC_SETUP_ACT,
209 					  fl_act, NULL, NULL);
210 	if (err < 0)
211 		return err;
212 
213 	if (hw_count)
214 		*hw_count = err;
215 
216 	return 0;
217 }
218 
219 static int tcf_action_offload_cmd_cb_ex(struct flow_offload_action *fl_act,
220 					u32 *hw_count,
221 					flow_indr_block_bind_cb_t *cb,
222 					void *cb_priv)
223 {
224 	int err;
225 
226 	err = cb(NULL, NULL, cb_priv, TC_SETUP_ACT, NULL, fl_act, NULL);
227 	if (err < 0)
228 		return err;
229 
230 	if (hw_count)
231 		*hw_count = 1;
232 
233 	return 0;
234 }
235 
236 static int tcf_action_offload_cmd(struct flow_offload_action *fl_act,
237 				  u32 *hw_count,
238 				  flow_indr_block_bind_cb_t *cb,
239 				  void *cb_priv)
240 {
241 	return cb ? tcf_action_offload_cmd_cb_ex(fl_act, hw_count,
242 						 cb, cb_priv) :
243 		    tcf_action_offload_cmd_ex(fl_act, hw_count);
244 }
245 
246 static int tcf_action_offload_add_ex(struct tc_action *action,
247 				     struct netlink_ext_ack *extack,
248 				     flow_indr_block_bind_cb_t *cb,
249 				     void *cb_priv)
250 {
251 	bool skip_sw = tc_act_skip_sw(action->tcfa_flags);
252 	struct tc_action *actions[TCA_ACT_MAX_PRIO] = {
253 		[0] = action,
254 	};
255 	struct flow_offload_action *fl_action;
256 	u32 in_hw_count = 0;
257 	int num, err = 0;
258 
259 	if (tc_act_skip_hw(action->tcfa_flags))
260 		return 0;
261 
262 	num = tcf_offload_act_num_actions_single(action);
263 	fl_action = offload_action_alloc(num);
264 	if (!fl_action)
265 		return -ENOMEM;
266 
267 	err = offload_action_init(fl_action, action, FLOW_ACT_REPLACE, extack);
268 	if (err)
269 		goto fl_err;
270 
271 	err = tc_setup_action(&fl_action->action, actions, 0, extack);
272 	if (err) {
273 		NL_SET_ERR_MSG_MOD(extack,
274 				   "Failed to setup tc actions for offload");
275 		goto fl_err;
276 	}
277 
278 	err = tcf_action_offload_cmd(fl_action, &in_hw_count, cb, cb_priv);
279 	if (!err)
280 		cb ? offload_action_hw_count_inc(action, in_hw_count) :
281 		     offload_action_hw_count_set(action, in_hw_count);
282 
283 	if (skip_sw && !tc_act_in_hw(action))
284 		err = -EINVAL;
285 
286 	tc_cleanup_offload_action(&fl_action->action);
287 
288 fl_err:
289 	kfree(fl_action);
290 
291 	return err;
292 }
293 
294 /* offload the tc action after it is inserted */
295 static int tcf_action_offload_add(struct tc_action *action,
296 				  struct netlink_ext_ack *extack)
297 {
298 	return tcf_action_offload_add_ex(action, extack, NULL, NULL);
299 }
300 
301 int tcf_action_update_hw_stats(struct tc_action *action)
302 {
303 	struct flow_offload_action fl_act = {};
304 	int err;
305 
306 	err = offload_action_init(&fl_act, action, FLOW_ACT_STATS, NULL);
307 	if (err)
308 		return err;
309 
310 	err = tcf_action_offload_cmd(&fl_act, NULL, NULL, NULL);
311 	if (!err) {
312 		preempt_disable();
313 		tcf_action_stats_update(action, fl_act.stats.bytes,
314 					fl_act.stats.pkts,
315 					fl_act.stats.drops,
316 					fl_act.stats.lastused,
317 					true);
318 		preempt_enable();
319 		action->used_hw_stats = fl_act.stats.used_hw_stats;
320 		action->used_hw_stats_valid = true;
321 	} else {
322 		return -EOPNOTSUPP;
323 	}
324 
325 	return 0;
326 }
327 EXPORT_SYMBOL(tcf_action_update_hw_stats);
328 
329 static int tcf_action_offload_del_ex(struct tc_action *action,
330 				     flow_indr_block_bind_cb_t *cb,
331 				     void *cb_priv)
332 {
333 	struct flow_offload_action fl_act = {};
334 	u32 in_hw_count = 0;
335 	int err = 0;
336 
337 	if (!tc_act_in_hw(action))
338 		return 0;
339 
340 	err = offload_action_init(&fl_act, action, FLOW_ACT_DESTROY, NULL);
341 	if (err)
342 		return err;
343 
344 	err = tcf_action_offload_cmd(&fl_act, &in_hw_count, cb, cb_priv);
345 	if (err < 0)
346 		return err;
347 
348 	if (!cb && action->in_hw_count != in_hw_count)
349 		return -EINVAL;
350 
351 	/* do not need to update hw state when deleting action */
352 	if (cb && in_hw_count)
353 		offload_action_hw_count_dec(action, in_hw_count);
354 
355 	return 0;
356 }
357 
358 static int tcf_action_offload_del(struct tc_action *action)
359 {
360 	return tcf_action_offload_del_ex(action, NULL, NULL);
361 }
362 
363 static void tcf_action_cleanup(struct tc_action *p)
364 {
365 	tcf_action_offload_del(p);
366 	if (p->ops->cleanup)
367 		p->ops->cleanup(p);
368 
369 	gen_kill_estimator(&p->tcfa_rate_est);
370 	free_tcf(p);
371 }
372 
373 static int __tcf_action_put(struct tc_action *p, bool bind)
374 {
375 	struct tcf_idrinfo *idrinfo = p->idrinfo;
376 
377 	if (refcount_dec_and_mutex_lock(&p->tcfa_refcnt, &idrinfo->lock)) {
378 		if (bind)
379 			atomic_dec(&p->tcfa_bindcnt);
380 		idr_remove(&idrinfo->action_idr, p->tcfa_index);
381 		mutex_unlock(&idrinfo->lock);
382 
383 		tcf_action_cleanup(p);
384 		return 1;
385 	}
386 
387 	if (bind)
388 		atomic_dec(&p->tcfa_bindcnt);
389 
390 	return 0;
391 }
392 
393 static int __tcf_idr_release(struct tc_action *p, bool bind, bool strict)
394 {
395 	int ret = 0;
396 
397 	/* Release with strict==1 and bind==0 is only called through act API
398 	 * interface (classifiers always bind). Only case when action with
399 	 * positive reference count and zero bind count can exist is when it was
400 	 * also created with act API (unbinding last classifier will destroy the
401 	 * action if it was created by classifier). So only case when bind count
402 	 * can be changed after initial check is when unbound action is
403 	 * destroyed by act API while classifier binds to action with same id
404 	 * concurrently. This result either creation of new action(same behavior
405 	 * as before), or reusing existing action if concurrent process
406 	 * increments reference count before action is deleted. Both scenarios
407 	 * are acceptable.
408 	 */
409 	if (p) {
410 		if (!bind && strict && atomic_read(&p->tcfa_bindcnt) > 0)
411 			return -EPERM;
412 
413 		if (__tcf_action_put(p, bind))
414 			ret = ACT_P_DELETED;
415 	}
416 
417 	return ret;
418 }
419 
420 int tcf_idr_release(struct tc_action *a, bool bind)
421 {
422 	const struct tc_action_ops *ops = a->ops;
423 	int ret;
424 
425 	ret = __tcf_idr_release(a, bind, false);
426 	if (ret == ACT_P_DELETED)
427 		module_put(ops->owner);
428 	return ret;
429 }
430 EXPORT_SYMBOL(tcf_idr_release);
431 
432 static size_t tcf_action_shared_attrs_size(const struct tc_action *act)
433 {
434 	struct tc_cookie *user_cookie;
435 	u32 cookie_len = 0;
436 
437 	rcu_read_lock();
438 	user_cookie = rcu_dereference(act->user_cookie);
439 
440 	if (user_cookie)
441 		cookie_len = nla_total_size(user_cookie->len);
442 	rcu_read_unlock();
443 
444 	return  nla_total_size(0) /* action number nested */
445 		+ nla_total_size(IFNAMSIZ) /* TCA_ACT_KIND */
446 		+ cookie_len /* TCA_ACT_COOKIE */
447 		+ nla_total_size(sizeof(struct nla_bitfield32)) /* TCA_ACT_HW_STATS */
448 		+ nla_total_size(0) /* TCA_ACT_STATS nested */
449 		+ nla_total_size(sizeof(struct nla_bitfield32)) /* TCA_ACT_FLAGS */
450 		/* TCA_STATS_BASIC */
451 		+ nla_total_size_64bit(sizeof(struct gnet_stats_basic))
452 		/* TCA_STATS_PKT64 */
453 		+ nla_total_size_64bit(sizeof(u64))
454 		/* TCA_STATS_QUEUE */
455 		+ nla_total_size_64bit(sizeof(struct gnet_stats_queue))
456 		+ nla_total_size(0) /* TCA_ACT_OPTIONS nested */
457 		+ nla_total_size(sizeof(struct tcf_t)); /* TCA_GACT_TM */
458 }
459 
460 static size_t tcf_action_full_attrs_size(size_t sz)
461 {
462 	return NLMSG_HDRLEN                     /* struct nlmsghdr */
463 		+ sizeof(struct tcamsg)
464 		+ nla_total_size(0)             /* TCA_ACT_TAB nested */
465 		+ sz;
466 }
467 
468 static size_t tcf_action_fill_size(const struct tc_action *act)
469 {
470 	size_t sz = tcf_action_shared_attrs_size(act);
471 
472 	if (act->ops->get_fill_size)
473 		return act->ops->get_fill_size(act) + sz;
474 	return sz;
475 }
476 
477 static int
478 tcf_action_dump_terse(struct sk_buff *skb, struct tc_action *a, bool from_act)
479 {
480 	unsigned char *b = skb_tail_pointer(skb);
481 	struct tc_cookie *cookie;
482 
483 	if (nla_put_string(skb, TCA_ACT_KIND, a->ops->kind))
484 		goto nla_put_failure;
485 	if (tcf_action_copy_stats(skb, a, 0))
486 		goto nla_put_failure;
487 	if (from_act && nla_put_u32(skb, TCA_ACT_INDEX, a->tcfa_index))
488 		goto nla_put_failure;
489 
490 	rcu_read_lock();
491 	cookie = rcu_dereference(a->user_cookie);
492 	if (cookie) {
493 		if (nla_put(skb, TCA_ACT_COOKIE, cookie->len, cookie->data)) {
494 			rcu_read_unlock();
495 			goto nla_put_failure;
496 		}
497 	}
498 	rcu_read_unlock();
499 
500 	return 0;
501 
502 nla_put_failure:
503 	nlmsg_trim(skb, b);
504 	return -1;
505 }
506 
507 static int tcf_dump_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb,
508 			   struct netlink_callback *cb)
509 {
510 	int err = 0, index = -1, s_i = 0, n_i = 0;
511 	u32 act_flags = cb->args[2];
512 	unsigned long jiffy_since = cb->args[3];
513 	struct nlattr *nest;
514 	struct idr *idr = &idrinfo->action_idr;
515 	struct tc_action *p;
516 	unsigned long id = 1;
517 	unsigned long tmp;
518 
519 	mutex_lock(&idrinfo->lock);
520 
521 	s_i = cb->args[0];
522 
523 	idr_for_each_entry_ul(idr, p, tmp, id) {
524 		index++;
525 		if (index < s_i)
526 			continue;
527 		if (IS_ERR(p))
528 			continue;
529 
530 		if (jiffy_since &&
531 		    time_after(jiffy_since,
532 			       (unsigned long)p->tcfa_tm.lastuse))
533 			continue;
534 
535 		tcf_action_update_hw_stats(p);
536 
537 		nest = nla_nest_start_noflag(skb, n_i);
538 		if (!nest) {
539 			index--;
540 			goto nla_put_failure;
541 		}
542 		err = (act_flags & TCA_ACT_FLAG_TERSE_DUMP) ?
543 			tcf_action_dump_terse(skb, p, true) :
544 			tcf_action_dump_1(skb, p, 0, 0);
545 		if (err < 0) {
546 			index--;
547 			nlmsg_trim(skb, nest);
548 			goto done;
549 		}
550 		nla_nest_end(skb, nest);
551 		n_i++;
552 		if (!(act_flags & TCA_ACT_FLAG_LARGE_DUMP_ON) &&
553 		    n_i >= TCA_ACT_MAX_PRIO)
554 			goto done;
555 	}
556 done:
557 	if (index >= 0)
558 		cb->args[0] = index + 1;
559 
560 	mutex_unlock(&idrinfo->lock);
561 	if (n_i) {
562 		if (act_flags & TCA_ACT_FLAG_LARGE_DUMP_ON)
563 			cb->args[1] = n_i;
564 	}
565 	return n_i;
566 
567 nla_put_failure:
568 	nla_nest_cancel(skb, nest);
569 	goto done;
570 }
571 
572 static int tcf_idr_release_unsafe(struct tc_action *p)
573 {
574 	if (atomic_read(&p->tcfa_bindcnt) > 0)
575 		return -EPERM;
576 
577 	if (refcount_dec_and_test(&p->tcfa_refcnt)) {
578 		idr_remove(&p->idrinfo->action_idr, p->tcfa_index);
579 		tcf_action_cleanup(p);
580 		return ACT_P_DELETED;
581 	}
582 
583 	return 0;
584 }
585 
586 static int tcf_del_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb,
587 			  const struct tc_action_ops *ops,
588 			  struct netlink_ext_ack *extack)
589 {
590 	struct nlattr *nest;
591 	int n_i = 0;
592 	int ret = -EINVAL;
593 	struct idr *idr = &idrinfo->action_idr;
594 	struct tc_action *p;
595 	unsigned long id = 1;
596 	unsigned long tmp;
597 
598 	nest = nla_nest_start_noflag(skb, 0);
599 	if (nest == NULL)
600 		goto nla_put_failure;
601 	if (nla_put_string(skb, TCA_ACT_KIND, ops->kind))
602 		goto nla_put_failure;
603 
604 	ret = 0;
605 	mutex_lock(&idrinfo->lock);
606 	idr_for_each_entry_ul(idr, p, tmp, id) {
607 		if (IS_ERR(p))
608 			continue;
609 		ret = tcf_idr_release_unsafe(p);
610 		if (ret == ACT_P_DELETED)
611 			module_put(ops->owner);
612 		else if (ret < 0)
613 			break;
614 		n_i++;
615 	}
616 	mutex_unlock(&idrinfo->lock);
617 	if (ret < 0) {
618 		if (n_i)
619 			NL_SET_ERR_MSG(extack, "Unable to flush all TC actions");
620 		else
621 			goto nla_put_failure;
622 	}
623 
624 	ret = nla_put_u32(skb, TCA_FCNT, n_i);
625 	if (ret)
626 		goto nla_put_failure;
627 	nla_nest_end(skb, nest);
628 
629 	return n_i;
630 nla_put_failure:
631 	nla_nest_cancel(skb, nest);
632 	return ret;
633 }
634 
635 int tcf_generic_walker(struct tc_action_net *tn, struct sk_buff *skb,
636 		       struct netlink_callback *cb, int type,
637 		       const struct tc_action_ops *ops,
638 		       struct netlink_ext_ack *extack)
639 {
640 	struct tcf_idrinfo *idrinfo = tn->idrinfo;
641 
642 	if (type == RTM_DELACTION) {
643 		return tcf_del_walker(idrinfo, skb, ops, extack);
644 	} else if (type == RTM_GETACTION) {
645 		return tcf_dump_walker(idrinfo, skb, cb);
646 	} else {
647 		WARN(1, "tcf_generic_walker: unknown command %d\n", type);
648 		NL_SET_ERR_MSG(extack, "tcf_generic_walker: unknown command");
649 		return -EINVAL;
650 	}
651 }
652 EXPORT_SYMBOL(tcf_generic_walker);
653 
654 int tcf_idr_search(struct tc_action_net *tn, struct tc_action **a, u32 index)
655 {
656 	struct tcf_idrinfo *idrinfo = tn->idrinfo;
657 	struct tc_action *p;
658 
659 	mutex_lock(&idrinfo->lock);
660 	p = idr_find(&idrinfo->action_idr, index);
661 	if (IS_ERR(p))
662 		p = NULL;
663 	else if (p)
664 		refcount_inc(&p->tcfa_refcnt);
665 	mutex_unlock(&idrinfo->lock);
666 
667 	if (p) {
668 		*a = p;
669 		return true;
670 	}
671 	return false;
672 }
673 EXPORT_SYMBOL(tcf_idr_search);
674 
675 static int __tcf_generic_walker(struct net *net, struct sk_buff *skb,
676 				struct netlink_callback *cb, int type,
677 				const struct tc_action_ops *ops,
678 				struct netlink_ext_ack *extack)
679 {
680 	struct tc_action_net *tn = net_generic(net, ops->net_id);
681 
682 	if (unlikely(ops->walk))
683 		return ops->walk(net, skb, cb, type, ops, extack);
684 
685 	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
686 }
687 
688 static int __tcf_idr_search(struct net *net,
689 			    const struct tc_action_ops *ops,
690 			    struct tc_action **a, u32 index)
691 {
692 	struct tc_action_net *tn = net_generic(net, ops->net_id);
693 
694 	if (unlikely(ops->lookup))
695 		return ops->lookup(net, a, index);
696 
697 	return tcf_idr_search(tn, a, index);
698 }
699 
700 static int tcf_idr_delete_index(struct tcf_idrinfo *idrinfo, u32 index)
701 {
702 	struct tc_action *p;
703 	int ret = 0;
704 
705 	mutex_lock(&idrinfo->lock);
706 	p = idr_find(&idrinfo->action_idr, index);
707 	if (!p) {
708 		mutex_unlock(&idrinfo->lock);
709 		return -ENOENT;
710 	}
711 
712 	if (!atomic_read(&p->tcfa_bindcnt)) {
713 		if (refcount_dec_and_test(&p->tcfa_refcnt)) {
714 			struct module *owner = p->ops->owner;
715 
716 			WARN_ON(p != idr_remove(&idrinfo->action_idr,
717 						p->tcfa_index));
718 			mutex_unlock(&idrinfo->lock);
719 
720 			tcf_action_cleanup(p);
721 			module_put(owner);
722 			return 0;
723 		}
724 		ret = 0;
725 	} else {
726 		ret = -EPERM;
727 	}
728 
729 	mutex_unlock(&idrinfo->lock);
730 	return ret;
731 }
732 
733 int tcf_idr_create(struct tc_action_net *tn, u32 index, struct nlattr *est,
734 		   struct tc_action **a, const struct tc_action_ops *ops,
735 		   int bind, bool cpustats, u32 flags)
736 {
737 	struct tc_action *p = kzalloc(ops->size, GFP_KERNEL);
738 	struct tcf_idrinfo *idrinfo = tn->idrinfo;
739 	int err = -ENOMEM;
740 
741 	if (unlikely(!p))
742 		return -ENOMEM;
743 	refcount_set(&p->tcfa_refcnt, 1);
744 	if (bind)
745 		atomic_set(&p->tcfa_bindcnt, 1);
746 
747 	if (cpustats) {
748 		p->cpu_bstats = netdev_alloc_pcpu_stats(struct gnet_stats_basic_sync);
749 		if (!p->cpu_bstats)
750 			goto err1;
751 		p->cpu_bstats_hw = netdev_alloc_pcpu_stats(struct gnet_stats_basic_sync);
752 		if (!p->cpu_bstats_hw)
753 			goto err2;
754 		p->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
755 		if (!p->cpu_qstats)
756 			goto err3;
757 	}
758 	gnet_stats_basic_sync_init(&p->tcfa_bstats);
759 	gnet_stats_basic_sync_init(&p->tcfa_bstats_hw);
760 	spin_lock_init(&p->tcfa_lock);
761 	p->tcfa_index = index;
762 	p->tcfa_tm.install = jiffies;
763 	p->tcfa_tm.lastuse = jiffies;
764 	p->tcfa_tm.firstuse = 0;
765 	p->tcfa_flags = flags;
766 	if (est) {
767 		err = gen_new_estimator(&p->tcfa_bstats, p->cpu_bstats,
768 					&p->tcfa_rate_est,
769 					&p->tcfa_lock, false, est);
770 		if (err)
771 			goto err4;
772 	}
773 
774 	p->idrinfo = idrinfo;
775 	__module_get(ops->owner);
776 	p->ops = ops;
777 	*a = p;
778 	return 0;
779 err4:
780 	free_percpu(p->cpu_qstats);
781 err3:
782 	free_percpu(p->cpu_bstats_hw);
783 err2:
784 	free_percpu(p->cpu_bstats);
785 err1:
786 	kfree(p);
787 	return err;
788 }
789 EXPORT_SYMBOL(tcf_idr_create);
790 
791 int tcf_idr_create_from_flags(struct tc_action_net *tn, u32 index,
792 			      struct nlattr *est, struct tc_action **a,
793 			      const struct tc_action_ops *ops, int bind,
794 			      u32 flags)
795 {
796 	/* Set cpustats according to actions flags. */
797 	return tcf_idr_create(tn, index, est, a, ops, bind,
798 			      !(flags & TCA_ACT_FLAGS_NO_PERCPU_STATS), flags);
799 }
800 EXPORT_SYMBOL(tcf_idr_create_from_flags);
801 
802 /* Cleanup idr index that was allocated but not initialized. */
803 
804 void tcf_idr_cleanup(struct tc_action_net *tn, u32 index)
805 {
806 	struct tcf_idrinfo *idrinfo = tn->idrinfo;
807 
808 	mutex_lock(&idrinfo->lock);
809 	/* Remove ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */
810 	WARN_ON(!IS_ERR(idr_remove(&idrinfo->action_idr, index)));
811 	mutex_unlock(&idrinfo->lock);
812 }
813 EXPORT_SYMBOL(tcf_idr_cleanup);
814 
815 /* Check if action with specified index exists. If actions is found, increments
816  * its reference and bind counters, and return 1. Otherwise insert temporary
817  * error pointer (to prevent concurrent users from inserting actions with same
818  * index) and return 0.
819  *
820  * May return -EAGAIN for binding actions in case of a parallel add/delete on
821  * the requested index.
822  */
823 
824 int tcf_idr_check_alloc(struct tc_action_net *tn, u32 *index,
825 			struct tc_action **a, int bind)
826 {
827 	struct tcf_idrinfo *idrinfo = tn->idrinfo;
828 	struct tc_action *p;
829 	int ret;
830 	u32 max;
831 
832 	if (*index) {
833 again:
834 		rcu_read_lock();
835 		p = idr_find(&idrinfo->action_idr, *index);
836 
837 		if (IS_ERR(p)) {
838 			/* This means that another process allocated
839 			 * index but did not assign the pointer yet.
840 			 */
841 			rcu_read_unlock();
842 			goto again;
843 		}
844 
845 		if (!p) {
846 			/* Empty slot, try to allocate it */
847 			max = *index;
848 			rcu_read_unlock();
849 			goto new;
850 		}
851 
852 		if (!refcount_inc_not_zero(&p->tcfa_refcnt)) {
853 			/* Action was deleted in parallel */
854 			rcu_read_unlock();
855 			return -EAGAIN;
856 		}
857 
858 		if (bind)
859 			atomic_inc(&p->tcfa_bindcnt);
860 		*a = p;
861 
862 		rcu_read_unlock();
863 
864 		return 1;
865 	} else {
866 		/* Find a slot */
867 		*index = 1;
868 		max = UINT_MAX;
869 	}
870 
871 new:
872 	*a = NULL;
873 
874 	mutex_lock(&idrinfo->lock);
875 	ret = idr_alloc_u32(&idrinfo->action_idr, ERR_PTR(-EBUSY), index, max,
876 			    GFP_KERNEL);
877 	mutex_unlock(&idrinfo->lock);
878 
879 	/* N binds raced for action allocation,
880 	 * retry for all the ones that failed.
881 	 */
882 	if (ret == -ENOSPC && *index == max)
883 		ret = -EAGAIN;
884 
885 	return ret;
886 }
887 EXPORT_SYMBOL(tcf_idr_check_alloc);
888 
889 void tcf_idrinfo_destroy(const struct tc_action_ops *ops,
890 			 struct tcf_idrinfo *idrinfo)
891 {
892 	struct idr *idr = &idrinfo->action_idr;
893 	struct tc_action *p;
894 	int ret;
895 	unsigned long id = 1;
896 	unsigned long tmp;
897 
898 	idr_for_each_entry_ul(idr, p, tmp, id) {
899 		ret = __tcf_idr_release(p, false, true);
900 		if (ret == ACT_P_DELETED)
901 			module_put(ops->owner);
902 		else if (ret < 0)
903 			return;
904 	}
905 	idr_destroy(&idrinfo->action_idr);
906 }
907 EXPORT_SYMBOL(tcf_idrinfo_destroy);
908 
909 static LIST_HEAD(act_base);
910 static DEFINE_RWLOCK(act_mod_lock);
911 /* since act ops id is stored in pernet subsystem list,
912  * then there is no way to walk through only all the action
913  * subsystem, so we keep tc action pernet ops id for
914  * reoffload to walk through.
915  */
916 static LIST_HEAD(act_pernet_id_list);
917 static DEFINE_MUTEX(act_id_mutex);
918 struct tc_act_pernet_id {
919 	struct list_head list;
920 	unsigned int id;
921 };
922 
923 static int tcf_pernet_add_id_list(unsigned int id)
924 {
925 	struct tc_act_pernet_id *id_ptr;
926 	int ret = 0;
927 
928 	mutex_lock(&act_id_mutex);
929 	list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
930 		if (id_ptr->id == id) {
931 			ret = -EEXIST;
932 			goto err_out;
933 		}
934 	}
935 
936 	id_ptr = kzalloc(sizeof(*id_ptr), GFP_KERNEL);
937 	if (!id_ptr) {
938 		ret = -ENOMEM;
939 		goto err_out;
940 	}
941 	id_ptr->id = id;
942 
943 	list_add_tail(&id_ptr->list, &act_pernet_id_list);
944 
945 err_out:
946 	mutex_unlock(&act_id_mutex);
947 	return ret;
948 }
949 
950 static void tcf_pernet_del_id_list(unsigned int id)
951 {
952 	struct tc_act_pernet_id *id_ptr;
953 
954 	mutex_lock(&act_id_mutex);
955 	list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
956 		if (id_ptr->id == id) {
957 			list_del(&id_ptr->list);
958 			kfree(id_ptr);
959 			break;
960 		}
961 	}
962 	mutex_unlock(&act_id_mutex);
963 }
964 
965 int tcf_register_action(struct tc_action_ops *act,
966 			struct pernet_operations *ops)
967 {
968 	struct tc_action_ops *a;
969 	int ret;
970 
971 	if (!act->act || !act->dump || !act->init)
972 		return -EINVAL;
973 
974 	/* We have to register pernet ops before making the action ops visible,
975 	 * otherwise tcf_action_init_1() could get a partially initialized
976 	 * netns.
977 	 */
978 	ret = register_pernet_subsys(ops);
979 	if (ret)
980 		return ret;
981 
982 	if (ops->id) {
983 		ret = tcf_pernet_add_id_list(*ops->id);
984 		if (ret)
985 			goto err_id;
986 	}
987 
988 	write_lock(&act_mod_lock);
989 	list_for_each_entry(a, &act_base, head) {
990 		if (act->id == a->id || (strcmp(act->kind, a->kind) == 0)) {
991 			ret = -EEXIST;
992 			goto err_out;
993 		}
994 	}
995 	list_add_tail(&act->head, &act_base);
996 	write_unlock(&act_mod_lock);
997 
998 	return 0;
999 
1000 err_out:
1001 	write_unlock(&act_mod_lock);
1002 	if (ops->id)
1003 		tcf_pernet_del_id_list(*ops->id);
1004 err_id:
1005 	unregister_pernet_subsys(ops);
1006 	return ret;
1007 }
1008 EXPORT_SYMBOL(tcf_register_action);
1009 
1010 int tcf_unregister_action(struct tc_action_ops *act,
1011 			  struct pernet_operations *ops)
1012 {
1013 	struct tc_action_ops *a;
1014 	int err = -ENOENT;
1015 
1016 	write_lock(&act_mod_lock);
1017 	list_for_each_entry(a, &act_base, head) {
1018 		if (a == act) {
1019 			list_del(&act->head);
1020 			err = 0;
1021 			break;
1022 		}
1023 	}
1024 	write_unlock(&act_mod_lock);
1025 	if (!err) {
1026 		unregister_pernet_subsys(ops);
1027 		if (ops->id)
1028 			tcf_pernet_del_id_list(*ops->id);
1029 	}
1030 	return err;
1031 }
1032 EXPORT_SYMBOL(tcf_unregister_action);
1033 
1034 /* lookup by name */
1035 static struct tc_action_ops *tc_lookup_action_n(char *kind)
1036 {
1037 	struct tc_action_ops *a, *res = NULL;
1038 
1039 	if (kind) {
1040 		read_lock(&act_mod_lock);
1041 		list_for_each_entry(a, &act_base, head) {
1042 			if (strcmp(kind, a->kind) == 0) {
1043 				if (try_module_get(a->owner))
1044 					res = a;
1045 				break;
1046 			}
1047 		}
1048 		read_unlock(&act_mod_lock);
1049 	}
1050 	return res;
1051 }
1052 
1053 /* lookup by nlattr */
1054 static struct tc_action_ops *tc_lookup_action(struct nlattr *kind)
1055 {
1056 	struct tc_action_ops *a, *res = NULL;
1057 
1058 	if (kind) {
1059 		read_lock(&act_mod_lock);
1060 		list_for_each_entry(a, &act_base, head) {
1061 			if (nla_strcmp(kind, a->kind) == 0) {
1062 				if (try_module_get(a->owner))
1063 					res = a;
1064 				break;
1065 			}
1066 		}
1067 		read_unlock(&act_mod_lock);
1068 	}
1069 	return res;
1070 }
1071 
1072 /*TCA_ACT_MAX_PRIO is 32, there count up to 32 */
1073 #define TCA_ACT_MAX_PRIO_MASK 0x1FF
1074 int tcf_action_exec(struct sk_buff *skb, struct tc_action **actions,
1075 		    int nr_actions, struct tcf_result *res)
1076 {
1077 	u32 jmp_prgcnt = 0;
1078 	u32 jmp_ttl = TCA_ACT_MAX_PRIO; /*matches actions per filter */
1079 	int i;
1080 	int ret = TC_ACT_OK;
1081 
1082 	if (skb_skip_tc_classify(skb))
1083 		return TC_ACT_OK;
1084 
1085 restart_act_graph:
1086 	for (i = 0; i < nr_actions; i++) {
1087 		const struct tc_action *a = actions[i];
1088 		int repeat_ttl;
1089 
1090 		if (jmp_prgcnt > 0) {
1091 			jmp_prgcnt -= 1;
1092 			continue;
1093 		}
1094 
1095 		if (tc_act_skip_sw(a->tcfa_flags))
1096 			continue;
1097 
1098 		repeat_ttl = 32;
1099 repeat:
1100 		ret = tc_act(skb, a, res);
1101 		if (unlikely(ret == TC_ACT_REPEAT)) {
1102 			if (--repeat_ttl != 0)
1103 				goto repeat;
1104 			/* suspicious opcode, stop pipeline */
1105 			net_warn_ratelimited("TC_ACT_REPEAT abuse ?\n");
1106 			return TC_ACT_OK;
1107 		}
1108 		if (TC_ACT_EXT_CMP(ret, TC_ACT_JUMP)) {
1109 			jmp_prgcnt = ret & TCA_ACT_MAX_PRIO_MASK;
1110 			if (!jmp_prgcnt || (jmp_prgcnt > nr_actions)) {
1111 				/* faulty opcode, stop pipeline */
1112 				return TC_ACT_OK;
1113 			} else {
1114 				jmp_ttl -= 1;
1115 				if (jmp_ttl > 0)
1116 					goto restart_act_graph;
1117 				else /* faulty graph, stop pipeline */
1118 					return TC_ACT_OK;
1119 			}
1120 		} else if (TC_ACT_EXT_CMP(ret, TC_ACT_GOTO_CHAIN)) {
1121 			if (unlikely(!rcu_access_pointer(a->goto_chain))) {
1122 				tcf_set_drop_reason(skb,
1123 						    SKB_DROP_REASON_TC_CHAIN_NOTFOUND);
1124 				return TC_ACT_SHOT;
1125 			}
1126 			tcf_action_goto_chain_exec(a, res);
1127 		}
1128 
1129 		if (ret != TC_ACT_PIPE)
1130 			break;
1131 	}
1132 
1133 	return ret;
1134 }
1135 EXPORT_SYMBOL(tcf_action_exec);
1136 
1137 int tcf_action_destroy(struct tc_action *actions[], int bind)
1138 {
1139 	const struct tc_action_ops *ops;
1140 	struct tc_action *a;
1141 	int ret = 0, i;
1142 
1143 	tcf_act_for_each_action(i, a, actions) {
1144 		actions[i] = NULL;
1145 		ops = a->ops;
1146 		ret = __tcf_idr_release(a, bind, true);
1147 		if (ret == ACT_P_DELETED)
1148 			module_put(ops->owner);
1149 		else if (ret < 0)
1150 			return ret;
1151 	}
1152 	return ret;
1153 }
1154 
1155 static int tcf_action_put(struct tc_action *p)
1156 {
1157 	return __tcf_action_put(p, false);
1158 }
1159 
1160 static void tcf_action_put_many(struct tc_action *actions[])
1161 {
1162 	struct tc_action *a;
1163 	int i;
1164 
1165 	tcf_act_for_each_action(i, a, actions) {
1166 		const struct tc_action_ops *ops = a->ops;
1167 		if (tcf_action_put(a))
1168 			module_put(ops->owner);
1169 	}
1170 }
1171 
1172 static void tca_put_bound_many(struct tc_action *actions[], int init_res[])
1173 {
1174 	struct tc_action *a;
1175 	int i;
1176 
1177 	tcf_act_for_each_action(i, a, actions) {
1178 		const struct tc_action_ops *ops = a->ops;
1179 
1180 		if (init_res[i] == ACT_P_CREATED)
1181 			continue;
1182 
1183 		if (tcf_action_put(a))
1184 			module_put(ops->owner);
1185 	}
1186 }
1187 
1188 int
1189 tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
1190 {
1191 	return a->ops->dump(skb, a, bind, ref);
1192 }
1193 
1194 int
1195 tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
1196 {
1197 	int err = -EINVAL;
1198 	unsigned char *b = skb_tail_pointer(skb);
1199 	struct nlattr *nest;
1200 	u32 flags;
1201 
1202 	if (tcf_action_dump_terse(skb, a, false))
1203 		goto nla_put_failure;
1204 
1205 	if (a->hw_stats != TCA_ACT_HW_STATS_ANY &&
1206 	    nla_put_bitfield32(skb, TCA_ACT_HW_STATS,
1207 			       a->hw_stats, TCA_ACT_HW_STATS_ANY))
1208 		goto nla_put_failure;
1209 
1210 	if (a->used_hw_stats_valid &&
1211 	    nla_put_bitfield32(skb, TCA_ACT_USED_HW_STATS,
1212 			       a->used_hw_stats, TCA_ACT_HW_STATS_ANY))
1213 		goto nla_put_failure;
1214 
1215 	flags = a->tcfa_flags & TCA_ACT_FLAGS_USER_MASK;
1216 	if (flags &&
1217 	    nla_put_bitfield32(skb, TCA_ACT_FLAGS,
1218 			       flags, flags))
1219 		goto nla_put_failure;
1220 
1221 	if (nla_put_u32(skb, TCA_ACT_IN_HW_COUNT, a->in_hw_count))
1222 		goto nla_put_failure;
1223 
1224 	nest = nla_nest_start_noflag(skb, TCA_ACT_OPTIONS);
1225 	if (nest == NULL)
1226 		goto nla_put_failure;
1227 	err = tcf_action_dump_old(skb, a, bind, ref);
1228 	if (err > 0) {
1229 		nla_nest_end(skb, nest);
1230 		return err;
1231 	}
1232 
1233 nla_put_failure:
1234 	nlmsg_trim(skb, b);
1235 	return -1;
1236 }
1237 EXPORT_SYMBOL(tcf_action_dump_1);
1238 
1239 int tcf_action_dump(struct sk_buff *skb, struct tc_action *actions[],
1240 		    int bind, int ref, bool terse)
1241 {
1242 	struct tc_action *a;
1243 	int err = -EINVAL, i;
1244 	struct nlattr *nest;
1245 
1246 	tcf_act_for_each_action(i, a, actions) {
1247 		nest = nla_nest_start_noflag(skb, i + 1);
1248 		if (nest == NULL)
1249 			goto nla_put_failure;
1250 		err = terse ? tcf_action_dump_terse(skb, a, false) :
1251 			tcf_action_dump_1(skb, a, bind, ref);
1252 		if (err < 0)
1253 			goto errout;
1254 		nla_nest_end(skb, nest);
1255 	}
1256 
1257 	return 0;
1258 
1259 nla_put_failure:
1260 	err = -EINVAL;
1261 errout:
1262 	nla_nest_cancel(skb, nest);
1263 	return err;
1264 }
1265 
1266 static struct tc_cookie *nla_memdup_cookie(struct nlattr **tb)
1267 {
1268 	struct tc_cookie *c = kzalloc(sizeof(*c), GFP_KERNEL);
1269 	if (!c)
1270 		return NULL;
1271 
1272 	c->data = nla_memdup(tb[TCA_ACT_COOKIE], GFP_KERNEL);
1273 	if (!c->data) {
1274 		kfree(c);
1275 		return NULL;
1276 	}
1277 	c->len = nla_len(tb[TCA_ACT_COOKIE]);
1278 
1279 	return c;
1280 }
1281 
1282 static u8 tcf_action_hw_stats_get(struct nlattr *hw_stats_attr)
1283 {
1284 	struct nla_bitfield32 hw_stats_bf;
1285 
1286 	/* If the user did not pass the attr, that means he does
1287 	 * not care about the type. Return "any" in that case
1288 	 * which is setting on all supported types.
1289 	 */
1290 	if (!hw_stats_attr)
1291 		return TCA_ACT_HW_STATS_ANY;
1292 	hw_stats_bf = nla_get_bitfield32(hw_stats_attr);
1293 	return hw_stats_bf.value;
1294 }
1295 
1296 static const struct nla_policy tcf_action_policy[TCA_ACT_MAX + 1] = {
1297 	[TCA_ACT_KIND]		= { .type = NLA_STRING },
1298 	[TCA_ACT_INDEX]		= { .type = NLA_U32 },
1299 	[TCA_ACT_COOKIE]	= { .type = NLA_BINARY,
1300 				    .len = TC_COOKIE_MAX_SIZE },
1301 	[TCA_ACT_OPTIONS]	= { .type = NLA_NESTED },
1302 	[TCA_ACT_FLAGS]		= NLA_POLICY_BITFIELD32(TCA_ACT_FLAGS_NO_PERCPU_STATS |
1303 							TCA_ACT_FLAGS_SKIP_HW |
1304 							TCA_ACT_FLAGS_SKIP_SW),
1305 	[TCA_ACT_HW_STATS]	= NLA_POLICY_BITFIELD32(TCA_ACT_HW_STATS_ANY),
1306 };
1307 
1308 void tcf_idr_insert_many(struct tc_action *actions[], int init_res[])
1309 {
1310 	struct tc_action *a;
1311 	int i;
1312 
1313 	tcf_act_for_each_action(i, a, actions) {
1314 		struct tcf_idrinfo *idrinfo;
1315 
1316 		if (init_res[i] == ACT_P_BOUND)
1317 			continue;
1318 
1319 		idrinfo = a->idrinfo;
1320 		mutex_lock(&idrinfo->lock);
1321 		/* Replace ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */
1322 		idr_replace(&idrinfo->action_idr, a, a->tcfa_index);
1323 		mutex_unlock(&idrinfo->lock);
1324 	}
1325 }
1326 
1327 struct tc_action_ops *tc_action_load_ops(struct nlattr *nla, u32 flags,
1328 					 struct netlink_ext_ack *extack)
1329 {
1330 	bool police = flags & TCA_ACT_FLAGS_POLICE;
1331 	struct nlattr *tb[TCA_ACT_MAX + 1];
1332 	struct tc_action_ops *a_o;
1333 	char act_name[IFNAMSIZ];
1334 	struct nlattr *kind;
1335 	int err;
1336 
1337 	if (!police) {
1338 		err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1339 						  tcf_action_policy, extack);
1340 		if (err < 0)
1341 			return ERR_PTR(err);
1342 		err = -EINVAL;
1343 		kind = tb[TCA_ACT_KIND];
1344 		if (!kind) {
1345 			NL_SET_ERR_MSG(extack, "TC action kind must be specified");
1346 			return ERR_PTR(err);
1347 		}
1348 		if (nla_strscpy(act_name, kind, IFNAMSIZ) < 0) {
1349 			NL_SET_ERR_MSG(extack, "TC action name too long");
1350 			return ERR_PTR(err);
1351 		}
1352 	} else {
1353 		if (strscpy(act_name, "police", IFNAMSIZ) < 0) {
1354 			NL_SET_ERR_MSG(extack, "TC action name too long");
1355 			return ERR_PTR(-EINVAL);
1356 		}
1357 	}
1358 
1359 	a_o = tc_lookup_action_n(act_name);
1360 	if (a_o == NULL) {
1361 #ifdef CONFIG_MODULES
1362 		bool rtnl_held = !(flags & TCA_ACT_FLAGS_NO_RTNL);
1363 
1364 		if (rtnl_held)
1365 			rtnl_unlock();
1366 		request_module("act_%s", act_name);
1367 		if (rtnl_held)
1368 			rtnl_lock();
1369 
1370 		a_o = tc_lookup_action_n(act_name);
1371 
1372 		/* We dropped the RTNL semaphore in order to
1373 		 * perform the module load.  So, even if we
1374 		 * succeeded in loading the module we have to
1375 		 * tell the caller to replay the request.  We
1376 		 * indicate this using -EAGAIN.
1377 		 */
1378 		if (a_o != NULL) {
1379 			module_put(a_o->owner);
1380 			return ERR_PTR(-EAGAIN);
1381 		}
1382 #endif
1383 		NL_SET_ERR_MSG(extack, "Failed to load TC action module");
1384 		return ERR_PTR(-ENOENT);
1385 	}
1386 
1387 	return a_o;
1388 }
1389 
1390 struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
1391 				    struct nlattr *nla, struct nlattr *est,
1392 				    struct tc_action_ops *a_o, int *init_res,
1393 				    u32 flags, struct netlink_ext_ack *extack)
1394 {
1395 	bool police = flags & TCA_ACT_FLAGS_POLICE;
1396 	struct nla_bitfield32 userflags = { 0, 0 };
1397 	struct tc_cookie *user_cookie = NULL;
1398 	u8 hw_stats = TCA_ACT_HW_STATS_ANY;
1399 	struct nlattr *tb[TCA_ACT_MAX + 1];
1400 	struct tc_action *a;
1401 	int err;
1402 
1403 	/* backward compatibility for policer */
1404 	if (!police) {
1405 		err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1406 						  tcf_action_policy, extack);
1407 		if (err < 0)
1408 			return ERR_PTR(err);
1409 		if (tb[TCA_ACT_COOKIE]) {
1410 			user_cookie = nla_memdup_cookie(tb);
1411 			if (!user_cookie) {
1412 				NL_SET_ERR_MSG(extack, "No memory to generate TC cookie");
1413 				err = -ENOMEM;
1414 				goto err_out;
1415 			}
1416 		}
1417 		hw_stats = tcf_action_hw_stats_get(tb[TCA_ACT_HW_STATS]);
1418 		if (tb[TCA_ACT_FLAGS]) {
1419 			userflags = nla_get_bitfield32(tb[TCA_ACT_FLAGS]);
1420 			if (!tc_act_flags_valid(userflags.value)) {
1421 				err = -EINVAL;
1422 				goto err_out;
1423 			}
1424 		}
1425 
1426 		err = a_o->init(net, tb[TCA_ACT_OPTIONS], est, &a, tp,
1427 				userflags.value | flags, extack);
1428 	} else {
1429 		err = a_o->init(net, nla, est, &a, tp, userflags.value | flags,
1430 				extack);
1431 	}
1432 	if (err < 0)
1433 		goto err_out;
1434 	*init_res = err;
1435 
1436 	if (!police && tb[TCA_ACT_COOKIE])
1437 		tcf_set_action_cookie(&a->user_cookie, user_cookie);
1438 
1439 	if (!police)
1440 		a->hw_stats = hw_stats;
1441 
1442 	return a;
1443 
1444 err_out:
1445 	if (user_cookie) {
1446 		kfree(user_cookie->data);
1447 		kfree(user_cookie);
1448 	}
1449 	return ERR_PTR(err);
1450 }
1451 
1452 static bool tc_act_bind(u32 flags)
1453 {
1454 	return !!(flags & TCA_ACT_FLAGS_BIND);
1455 }
1456 
1457 /* Returns numbers of initialized actions or negative error. */
1458 
1459 int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla,
1460 		    struct nlattr *est, struct tc_action *actions[],
1461 		    int init_res[], size_t *attr_size,
1462 		    u32 flags, u32 fl_flags,
1463 		    struct netlink_ext_ack *extack)
1464 {
1465 	struct tc_action_ops *ops[TCA_ACT_MAX_PRIO] = {};
1466 	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1467 	struct tc_action *act;
1468 	size_t sz = 0;
1469 	int err;
1470 	int i;
1471 
1472 	err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX_PRIO, nla, NULL,
1473 					  extack);
1474 	if (err < 0)
1475 		return err;
1476 
1477 	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1478 		struct tc_action_ops *a_o;
1479 
1480 		a_o = tc_action_load_ops(tb[i], flags, extack);
1481 		if (IS_ERR(a_o)) {
1482 			err = PTR_ERR(a_o);
1483 			goto err_mod;
1484 		}
1485 		ops[i - 1] = a_o;
1486 	}
1487 
1488 	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1489 		act = tcf_action_init_1(net, tp, tb[i], est, ops[i - 1],
1490 					&init_res[i - 1], flags, extack);
1491 		if (IS_ERR(act)) {
1492 			err = PTR_ERR(act);
1493 			goto err;
1494 		}
1495 		sz += tcf_action_fill_size(act);
1496 		/* Start from index 0 */
1497 		actions[i - 1] = act;
1498 		if (tc_act_bind(flags)) {
1499 			bool skip_sw = tc_skip_sw(fl_flags);
1500 			bool skip_hw = tc_skip_hw(fl_flags);
1501 
1502 			if (tc_act_bind(act->tcfa_flags))
1503 				continue;
1504 			if (skip_sw != tc_act_skip_sw(act->tcfa_flags) ||
1505 			    skip_hw != tc_act_skip_hw(act->tcfa_flags)) {
1506 				NL_SET_ERR_MSG(extack,
1507 					       "Mismatch between action and filter offload flags");
1508 				err = -EINVAL;
1509 				goto err;
1510 			}
1511 		} else {
1512 			err = tcf_action_offload_add(act, extack);
1513 			if (tc_act_skip_sw(act->tcfa_flags) && err)
1514 				goto err;
1515 		}
1516 	}
1517 
1518 	/* We have to commit them all together, because if any error happened in
1519 	 * between, we could not handle the failure gracefully.
1520 	 */
1521 	tcf_idr_insert_many(actions, init_res);
1522 
1523 	*attr_size = tcf_action_full_attrs_size(sz);
1524 	err = i - 1;
1525 	goto err_mod;
1526 
1527 err:
1528 	tcf_action_destroy(actions, flags & TCA_ACT_FLAGS_BIND);
1529 err_mod:
1530 	for (i = 0; i < TCA_ACT_MAX_PRIO && ops[i]; i++)
1531 		module_put(ops[i]->owner);
1532 	return err;
1533 }
1534 
1535 void tcf_action_update_stats(struct tc_action *a, u64 bytes, u64 packets,
1536 			     u64 drops, bool hw)
1537 {
1538 	if (a->cpu_bstats) {
1539 		_bstats_update(this_cpu_ptr(a->cpu_bstats), bytes, packets);
1540 
1541 		this_cpu_ptr(a->cpu_qstats)->drops += drops;
1542 
1543 		if (hw)
1544 			_bstats_update(this_cpu_ptr(a->cpu_bstats_hw),
1545 				       bytes, packets);
1546 		return;
1547 	}
1548 
1549 	_bstats_update(&a->tcfa_bstats, bytes, packets);
1550 	a->tcfa_qstats.drops += drops;
1551 	if (hw)
1552 		_bstats_update(&a->tcfa_bstats_hw, bytes, packets);
1553 }
1554 EXPORT_SYMBOL(tcf_action_update_stats);
1555 
1556 int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *p,
1557 			  int compat_mode)
1558 {
1559 	int err = 0;
1560 	struct gnet_dump d;
1561 
1562 	if (p == NULL)
1563 		goto errout;
1564 
1565 	/* compat_mode being true specifies a call that is supposed
1566 	 * to add additional backward compatibility statistic TLVs.
1567 	 */
1568 	if (compat_mode) {
1569 		if (p->type == TCA_OLD_COMPAT)
1570 			err = gnet_stats_start_copy_compat(skb, 0,
1571 							   TCA_STATS,
1572 							   TCA_XSTATS,
1573 							   &p->tcfa_lock, &d,
1574 							   TCA_PAD);
1575 		else
1576 			return 0;
1577 	} else
1578 		err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
1579 					    &p->tcfa_lock, &d, TCA_ACT_PAD);
1580 
1581 	if (err < 0)
1582 		goto errout;
1583 
1584 	if (gnet_stats_copy_basic(&d, p->cpu_bstats,
1585 				  &p->tcfa_bstats, false) < 0 ||
1586 	    gnet_stats_copy_basic_hw(&d, p->cpu_bstats_hw,
1587 				     &p->tcfa_bstats_hw, false) < 0 ||
1588 	    gnet_stats_copy_rate_est(&d, &p->tcfa_rate_est) < 0 ||
1589 	    gnet_stats_copy_queue(&d, p->cpu_qstats,
1590 				  &p->tcfa_qstats,
1591 				  p->tcfa_qstats.qlen) < 0)
1592 		goto errout;
1593 
1594 	if (gnet_stats_finish_copy(&d) < 0)
1595 		goto errout;
1596 
1597 	return 0;
1598 
1599 errout:
1600 	return -1;
1601 }
1602 
1603 static int tca_get_fill(struct sk_buff *skb, struct tc_action *actions[],
1604 			u32 portid, u32 seq, u16 flags, int event, int bind,
1605 			int ref, struct netlink_ext_ack *extack)
1606 {
1607 	struct tcamsg *t;
1608 	struct nlmsghdr *nlh;
1609 	unsigned char *b = skb_tail_pointer(skb);
1610 	struct nlattr *nest;
1611 
1612 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*t), flags);
1613 	if (!nlh)
1614 		goto out_nlmsg_trim;
1615 	t = nlmsg_data(nlh);
1616 	t->tca_family = AF_UNSPEC;
1617 	t->tca__pad1 = 0;
1618 	t->tca__pad2 = 0;
1619 
1620 	if (extack && extack->_msg &&
1621 	    nla_put_string(skb, TCA_ROOT_EXT_WARN_MSG, extack->_msg))
1622 		goto out_nlmsg_trim;
1623 
1624 	nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
1625 	if (!nest)
1626 		goto out_nlmsg_trim;
1627 
1628 	if (tcf_action_dump(skb, actions, bind, ref, false) < 0)
1629 		goto out_nlmsg_trim;
1630 
1631 	nla_nest_end(skb, nest);
1632 
1633 	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1634 
1635 	return skb->len;
1636 
1637 out_nlmsg_trim:
1638 	nlmsg_trim(skb, b);
1639 	return -1;
1640 }
1641 
1642 static int
1643 tcf_get_notify(struct net *net, u32 portid, struct nlmsghdr *n,
1644 	       struct tc_action *actions[], int event,
1645 	       struct netlink_ext_ack *extack)
1646 {
1647 	struct sk_buff *skb;
1648 
1649 	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1650 	if (!skb)
1651 		return -ENOBUFS;
1652 	if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, event,
1653 			 0, 1, NULL) <= 0) {
1654 		NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1655 		kfree_skb(skb);
1656 		return -EINVAL;
1657 	}
1658 
1659 	return rtnl_unicast(skb, net, portid);
1660 }
1661 
1662 static struct tc_action *tcf_action_get_1(struct net *net, struct nlattr *nla,
1663 					  struct nlmsghdr *n, u32 portid,
1664 					  struct netlink_ext_ack *extack)
1665 {
1666 	struct nlattr *tb[TCA_ACT_MAX + 1];
1667 	const struct tc_action_ops *ops;
1668 	struct tc_action *a;
1669 	int index;
1670 	int err;
1671 
1672 	err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1673 					  tcf_action_policy, extack);
1674 	if (err < 0)
1675 		goto err_out;
1676 
1677 	err = -EINVAL;
1678 	if (tb[TCA_ACT_INDEX] == NULL ||
1679 	    nla_len(tb[TCA_ACT_INDEX]) < sizeof(index)) {
1680 		NL_SET_ERR_MSG(extack, "Invalid TC action index value");
1681 		goto err_out;
1682 	}
1683 	index = nla_get_u32(tb[TCA_ACT_INDEX]);
1684 
1685 	err = -EINVAL;
1686 	ops = tc_lookup_action(tb[TCA_ACT_KIND]);
1687 	if (!ops) { /* could happen in batch of actions */
1688 		NL_SET_ERR_MSG(extack, "Specified TC action kind not found");
1689 		goto err_out;
1690 	}
1691 	err = -ENOENT;
1692 	if (__tcf_idr_search(net, ops, &a, index) == 0) {
1693 		NL_SET_ERR_MSG(extack, "TC action with specified index not found");
1694 		goto err_mod;
1695 	}
1696 
1697 	module_put(ops->owner);
1698 	return a;
1699 
1700 err_mod:
1701 	module_put(ops->owner);
1702 err_out:
1703 	return ERR_PTR(err);
1704 }
1705 
1706 static int tca_action_flush(struct net *net, struct nlattr *nla,
1707 			    struct nlmsghdr *n, u32 portid,
1708 			    struct netlink_ext_ack *extack)
1709 {
1710 	struct sk_buff *skb;
1711 	unsigned char *b;
1712 	struct nlmsghdr *nlh;
1713 	struct tcamsg *t;
1714 	struct netlink_callback dcb;
1715 	struct nlattr *nest;
1716 	struct nlattr *tb[TCA_ACT_MAX + 1];
1717 	const struct tc_action_ops *ops;
1718 	struct nlattr *kind;
1719 	int err = -ENOMEM;
1720 
1721 	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1722 	if (!skb)
1723 		return err;
1724 
1725 	b = skb_tail_pointer(skb);
1726 
1727 	err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1728 					  tcf_action_policy, extack);
1729 	if (err < 0)
1730 		goto err_out;
1731 
1732 	err = -EINVAL;
1733 	kind = tb[TCA_ACT_KIND];
1734 	ops = tc_lookup_action(kind);
1735 	if (!ops) { /*some idjot trying to flush unknown action */
1736 		NL_SET_ERR_MSG(extack, "Cannot flush unknown TC action");
1737 		goto err_out;
1738 	}
1739 
1740 	nlh = nlmsg_put(skb, portid, n->nlmsg_seq, RTM_DELACTION,
1741 			sizeof(*t), 0);
1742 	if (!nlh) {
1743 		NL_SET_ERR_MSG(extack, "Failed to create TC action flush notification");
1744 		goto out_module_put;
1745 	}
1746 	t = nlmsg_data(nlh);
1747 	t->tca_family = AF_UNSPEC;
1748 	t->tca__pad1 = 0;
1749 	t->tca__pad2 = 0;
1750 
1751 	nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
1752 	if (!nest) {
1753 		NL_SET_ERR_MSG(extack, "Failed to add new netlink message");
1754 		goto out_module_put;
1755 	}
1756 
1757 	err = __tcf_generic_walker(net, skb, &dcb, RTM_DELACTION, ops, extack);
1758 	if (err <= 0) {
1759 		nla_nest_cancel(skb, nest);
1760 		goto out_module_put;
1761 	}
1762 
1763 	nla_nest_end(skb, nest);
1764 
1765 	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1766 	nlh->nlmsg_flags |= NLM_F_ROOT;
1767 	module_put(ops->owner);
1768 	err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1769 			     n->nlmsg_flags & NLM_F_ECHO);
1770 	if (err < 0)
1771 		NL_SET_ERR_MSG(extack, "Failed to send TC action flush notification");
1772 
1773 	return err;
1774 
1775 out_module_put:
1776 	module_put(ops->owner);
1777 err_out:
1778 	kfree_skb(skb);
1779 	return err;
1780 }
1781 
1782 static int tcf_action_delete(struct net *net, struct tc_action *actions[])
1783 {
1784 	struct tc_action *a;
1785 	int i;
1786 
1787 	tcf_act_for_each_action(i, a, actions) {
1788 		const struct tc_action_ops *ops = a->ops;
1789 		/* Actions can be deleted concurrently so we must save their
1790 		 * type and id to search again after reference is released.
1791 		 */
1792 		struct tcf_idrinfo *idrinfo = a->idrinfo;
1793 		u32 act_index = a->tcfa_index;
1794 
1795 		actions[i] = NULL;
1796 		if (tcf_action_put(a)) {
1797 			/* last reference, action was deleted concurrently */
1798 			module_put(ops->owner);
1799 		} else {
1800 			int ret;
1801 
1802 			/* now do the delete */
1803 			ret = tcf_idr_delete_index(idrinfo, act_index);
1804 			if (ret < 0)
1805 				return ret;
1806 		}
1807 	}
1808 	return 0;
1809 }
1810 
1811 static struct sk_buff *tcf_reoffload_del_notify_msg(struct net *net,
1812 						    struct tc_action *action)
1813 {
1814 	size_t attr_size = tcf_action_fill_size(action);
1815 	struct tc_action *actions[TCA_ACT_MAX_PRIO] = {
1816 		[0] = action,
1817 	};
1818 	struct sk_buff *skb;
1819 
1820 	skb = alloc_skb(max(attr_size, NLMSG_GOODSIZE), GFP_KERNEL);
1821 	if (!skb)
1822 		return ERR_PTR(-ENOBUFS);
1823 
1824 	if (tca_get_fill(skb, actions, 0, 0, 0, RTM_DELACTION, 0, 1, NULL) <= 0) {
1825 		kfree_skb(skb);
1826 		return ERR_PTR(-EINVAL);
1827 	}
1828 
1829 	return skb;
1830 }
1831 
1832 static int tcf_reoffload_del_notify(struct net *net, struct tc_action *action)
1833 {
1834 	const struct tc_action_ops *ops = action->ops;
1835 	struct sk_buff *skb;
1836 	int ret;
1837 
1838 	if (!rtnl_notify_needed(net, 0, RTNLGRP_TC)) {
1839 		skb = NULL;
1840 	} else {
1841 		skb = tcf_reoffload_del_notify_msg(net, action);
1842 		if (IS_ERR(skb))
1843 			return PTR_ERR(skb);
1844 	}
1845 
1846 	ret = tcf_idr_release_unsafe(action);
1847 	if (ret == ACT_P_DELETED) {
1848 		module_put(ops->owner);
1849 		ret = rtnetlink_maybe_send(skb, net, 0, RTNLGRP_TC, 0);
1850 	} else {
1851 		kfree_skb(skb);
1852 	}
1853 
1854 	return ret;
1855 }
1856 
1857 int tcf_action_reoffload_cb(flow_indr_block_bind_cb_t *cb,
1858 			    void *cb_priv, bool add)
1859 {
1860 	struct tc_act_pernet_id *id_ptr;
1861 	struct tcf_idrinfo *idrinfo;
1862 	struct tc_action_net *tn;
1863 	struct tc_action *p;
1864 	unsigned int act_id;
1865 	unsigned long tmp;
1866 	unsigned long id;
1867 	struct idr *idr;
1868 	struct net *net;
1869 	int ret;
1870 
1871 	if (!cb)
1872 		return -EINVAL;
1873 
1874 	down_read(&net_rwsem);
1875 	mutex_lock(&act_id_mutex);
1876 
1877 	for_each_net(net) {
1878 		list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
1879 			act_id = id_ptr->id;
1880 			tn = net_generic(net, act_id);
1881 			if (!tn)
1882 				continue;
1883 			idrinfo = tn->idrinfo;
1884 			if (!idrinfo)
1885 				continue;
1886 
1887 			mutex_lock(&idrinfo->lock);
1888 			idr = &idrinfo->action_idr;
1889 			idr_for_each_entry_ul(idr, p, tmp, id) {
1890 				if (IS_ERR(p) || tc_act_bind(p->tcfa_flags))
1891 					continue;
1892 				if (add) {
1893 					tcf_action_offload_add_ex(p, NULL, cb,
1894 								  cb_priv);
1895 					continue;
1896 				}
1897 
1898 				/* cb unregister to update hw count */
1899 				ret = tcf_action_offload_del_ex(p, cb, cb_priv);
1900 				if (ret < 0)
1901 					continue;
1902 				if (tc_act_skip_sw(p->tcfa_flags) &&
1903 				    !tc_act_in_hw(p))
1904 					tcf_reoffload_del_notify(net, p);
1905 			}
1906 			mutex_unlock(&idrinfo->lock);
1907 		}
1908 	}
1909 	mutex_unlock(&act_id_mutex);
1910 	up_read(&net_rwsem);
1911 
1912 	return 0;
1913 }
1914 
1915 static struct sk_buff *tcf_del_notify_msg(struct net *net, struct nlmsghdr *n,
1916 					  struct tc_action *actions[],
1917 					  u32 portid, size_t attr_size,
1918 					  struct netlink_ext_ack *extack)
1919 {
1920 	struct sk_buff *skb;
1921 
1922 	skb = alloc_skb(max(attr_size, NLMSG_GOODSIZE), GFP_KERNEL);
1923 	if (!skb)
1924 		return ERR_PTR(-ENOBUFS);
1925 
1926 	if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, RTM_DELACTION,
1927 			 0, 2, extack) <= 0) {
1928 		NL_SET_ERR_MSG(extack, "Failed to fill netlink TC action attributes");
1929 		kfree_skb(skb);
1930 		return ERR_PTR(-EINVAL);
1931 	}
1932 
1933 	return skb;
1934 }
1935 
1936 static int tcf_del_notify(struct net *net, struct nlmsghdr *n,
1937 			  struct tc_action *actions[], u32 portid,
1938 			  size_t attr_size, struct netlink_ext_ack *extack)
1939 {
1940 	struct sk_buff *skb;
1941 	int ret;
1942 
1943 	if (!rtnl_notify_needed(net, n->nlmsg_flags, RTNLGRP_TC)) {
1944 		skb = NULL;
1945 	} else {
1946 		skb = tcf_del_notify_msg(net, n, actions, portid, attr_size,
1947 					 extack);
1948 		if (IS_ERR(skb))
1949 			return PTR_ERR(skb);
1950 	}
1951 
1952 	/* now do the delete */
1953 	ret = tcf_action_delete(net, actions);
1954 	if (ret < 0) {
1955 		NL_SET_ERR_MSG(extack, "Failed to delete TC action");
1956 		kfree_skb(skb);
1957 		return ret;
1958 	}
1959 
1960 	return rtnetlink_maybe_send(skb, net, portid, RTNLGRP_TC,
1961 				    n->nlmsg_flags & NLM_F_ECHO);
1962 }
1963 
1964 static int
1965 tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
1966 	      u32 portid, int event, struct netlink_ext_ack *extack)
1967 {
1968 	int i, ret;
1969 	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1970 	struct tc_action *act;
1971 	size_t attr_size = 0;
1972 	struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
1973 
1974 	ret = nla_parse_nested_deprecated(tb, TCA_ACT_MAX_PRIO, nla, NULL,
1975 					  extack);
1976 	if (ret < 0)
1977 		return ret;
1978 
1979 	if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) {
1980 		if (tb[1])
1981 			return tca_action_flush(net, tb[1], n, portid, extack);
1982 
1983 		NL_SET_ERR_MSG(extack, "Invalid netlink attributes while flushing TC action");
1984 		return -EINVAL;
1985 	}
1986 
1987 	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1988 		act = tcf_action_get_1(net, tb[i], n, portid, extack);
1989 		if (IS_ERR(act)) {
1990 			ret = PTR_ERR(act);
1991 			goto err;
1992 		}
1993 		attr_size += tcf_action_fill_size(act);
1994 		actions[i - 1] = act;
1995 	}
1996 
1997 	attr_size = tcf_action_full_attrs_size(attr_size);
1998 
1999 	if (event == RTM_GETACTION)
2000 		ret = tcf_get_notify(net, portid, n, actions, event, extack);
2001 	else { /* delete */
2002 		ret = tcf_del_notify(net, n, actions, portid, attr_size, extack);
2003 		if (ret)
2004 			goto err;
2005 		return 0;
2006 	}
2007 err:
2008 	tcf_action_put_many(actions);
2009 	return ret;
2010 }
2011 
2012 static struct sk_buff *tcf_add_notify_msg(struct net *net, struct nlmsghdr *n,
2013 					  struct tc_action *actions[],
2014 					  u32 portid, size_t attr_size,
2015 					  struct netlink_ext_ack *extack)
2016 {
2017 	struct sk_buff *skb;
2018 
2019 	skb = alloc_skb(max(attr_size, NLMSG_GOODSIZE), GFP_KERNEL);
2020 	if (!skb)
2021 		return ERR_PTR(-ENOBUFS);
2022 
2023 	if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, n->nlmsg_flags,
2024 			 RTM_NEWACTION, 0, 0, extack) <= 0) {
2025 		NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
2026 		kfree_skb(skb);
2027 		return ERR_PTR(-EINVAL);
2028 	}
2029 
2030 	return skb;
2031 }
2032 
2033 static int tcf_add_notify(struct net *net, struct nlmsghdr *n,
2034 			  struct tc_action *actions[], u32 portid,
2035 			  size_t attr_size, struct netlink_ext_ack *extack)
2036 {
2037 	struct sk_buff *skb;
2038 
2039 	if (!rtnl_notify_needed(net, n->nlmsg_flags, RTNLGRP_TC)) {
2040 		skb = NULL;
2041 	} else {
2042 		skb = tcf_add_notify_msg(net, n, actions, portid, attr_size,
2043 					 extack);
2044 		if (IS_ERR(skb))
2045 			return PTR_ERR(skb);
2046 	}
2047 
2048 	return rtnetlink_maybe_send(skb, net, portid, RTNLGRP_TC,
2049 				    n->nlmsg_flags & NLM_F_ECHO);
2050 }
2051 
2052 static int tcf_action_add(struct net *net, struct nlattr *nla,
2053 			  struct nlmsghdr *n, u32 portid, u32 flags,
2054 			  struct netlink_ext_ack *extack)
2055 {
2056 	size_t attr_size = 0;
2057 	int loop, ret;
2058 	struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
2059 	int init_res[TCA_ACT_MAX_PRIO] = {};
2060 
2061 	for (loop = 0; loop < 10; loop++) {
2062 		ret = tcf_action_init(net, NULL, nla, NULL, actions, init_res,
2063 				      &attr_size, flags, 0, extack);
2064 		if (ret != -EAGAIN)
2065 			break;
2066 	}
2067 
2068 	if (ret < 0)
2069 		return ret;
2070 
2071 	ret = tcf_add_notify(net, n, actions, portid, attr_size, extack);
2072 
2073 	/* only put bound actions */
2074 	tca_put_bound_many(actions, init_res);
2075 
2076 	return ret;
2077 }
2078 
2079 static const struct nla_policy tcaa_policy[TCA_ROOT_MAX + 1] = {
2080 	[TCA_ROOT_FLAGS] = NLA_POLICY_BITFIELD32(TCA_ACT_FLAG_LARGE_DUMP_ON |
2081 						 TCA_ACT_FLAG_TERSE_DUMP),
2082 	[TCA_ROOT_TIME_DELTA]      = { .type = NLA_U32 },
2083 };
2084 
2085 static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n,
2086 			 struct netlink_ext_ack *extack)
2087 {
2088 	struct net *net = sock_net(skb->sk);
2089 	struct nlattr *tca[TCA_ROOT_MAX + 1];
2090 	u32 portid = NETLINK_CB(skb).portid;
2091 	u32 flags = 0;
2092 	int ret = 0;
2093 
2094 	if ((n->nlmsg_type != RTM_GETACTION) &&
2095 	    !netlink_capable(skb, CAP_NET_ADMIN))
2096 		return -EPERM;
2097 
2098 	ret = nlmsg_parse_deprecated(n, sizeof(struct tcamsg), tca,
2099 				     TCA_ROOT_MAX, NULL, extack);
2100 	if (ret < 0)
2101 		return ret;
2102 
2103 	if (tca[TCA_ACT_TAB] == NULL) {
2104 		NL_SET_ERR_MSG(extack, "Netlink action attributes missing");
2105 		return -EINVAL;
2106 	}
2107 
2108 	/* n->nlmsg_flags & NLM_F_CREATE */
2109 	switch (n->nlmsg_type) {
2110 	case RTM_NEWACTION:
2111 		/* we are going to assume all other flags
2112 		 * imply create only if it doesn't exist
2113 		 * Note that CREATE | EXCL implies that
2114 		 * but since we want avoid ambiguity (eg when flags
2115 		 * is zero) then just set this
2116 		 */
2117 		if (n->nlmsg_flags & NLM_F_REPLACE)
2118 			flags = TCA_ACT_FLAGS_REPLACE;
2119 		ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, portid, flags,
2120 				     extack);
2121 		break;
2122 	case RTM_DELACTION:
2123 		ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
2124 				    portid, RTM_DELACTION, extack);
2125 		break;
2126 	case RTM_GETACTION:
2127 		ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
2128 				    portid, RTM_GETACTION, extack);
2129 		break;
2130 	default:
2131 		BUG();
2132 	}
2133 
2134 	return ret;
2135 }
2136 
2137 static struct nlattr *find_dump_kind(struct nlattr **nla)
2138 {
2139 	struct nlattr *tb1, *tb2[TCA_ACT_MAX + 1];
2140 	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
2141 	struct nlattr *kind;
2142 
2143 	tb1 = nla[TCA_ACT_TAB];
2144 	if (tb1 == NULL)
2145 		return NULL;
2146 
2147 	if (nla_parse_deprecated(tb, TCA_ACT_MAX_PRIO, nla_data(tb1), NLMSG_ALIGN(nla_len(tb1)), NULL, NULL) < 0)
2148 		return NULL;
2149 
2150 	if (tb[1] == NULL)
2151 		return NULL;
2152 	if (nla_parse_nested_deprecated(tb2, TCA_ACT_MAX, tb[1], tcf_action_policy, NULL) < 0)
2153 		return NULL;
2154 	kind = tb2[TCA_ACT_KIND];
2155 
2156 	return kind;
2157 }
2158 
2159 static int tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
2160 {
2161 	struct net *net = sock_net(skb->sk);
2162 	struct nlmsghdr *nlh;
2163 	unsigned char *b = skb_tail_pointer(skb);
2164 	struct nlattr *nest;
2165 	struct tc_action_ops *a_o;
2166 	int ret = 0;
2167 	struct tcamsg *t = (struct tcamsg *) nlmsg_data(cb->nlh);
2168 	struct nlattr *tb[TCA_ROOT_MAX + 1];
2169 	struct nlattr *count_attr = NULL;
2170 	unsigned long jiffy_since = 0;
2171 	struct nlattr *kind = NULL;
2172 	struct nla_bitfield32 bf;
2173 	u32 msecs_since = 0;
2174 	u32 act_count = 0;
2175 
2176 	ret = nlmsg_parse_deprecated(cb->nlh, sizeof(struct tcamsg), tb,
2177 				     TCA_ROOT_MAX, tcaa_policy, cb->extack);
2178 	if (ret < 0)
2179 		return ret;
2180 
2181 	kind = find_dump_kind(tb);
2182 	if (kind == NULL) {
2183 		pr_info("tc_dump_action: action bad kind\n");
2184 		return 0;
2185 	}
2186 
2187 	a_o = tc_lookup_action(kind);
2188 	if (a_o == NULL)
2189 		return 0;
2190 
2191 	cb->args[2] = 0;
2192 	if (tb[TCA_ROOT_FLAGS]) {
2193 		bf = nla_get_bitfield32(tb[TCA_ROOT_FLAGS]);
2194 		cb->args[2] = bf.value;
2195 	}
2196 
2197 	if (tb[TCA_ROOT_TIME_DELTA]) {
2198 		msecs_since = nla_get_u32(tb[TCA_ROOT_TIME_DELTA]);
2199 	}
2200 
2201 	nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
2202 			cb->nlh->nlmsg_type, sizeof(*t), 0);
2203 	if (!nlh)
2204 		goto out_module_put;
2205 
2206 	if (msecs_since)
2207 		jiffy_since = jiffies - msecs_to_jiffies(msecs_since);
2208 
2209 	t = nlmsg_data(nlh);
2210 	t->tca_family = AF_UNSPEC;
2211 	t->tca__pad1 = 0;
2212 	t->tca__pad2 = 0;
2213 	cb->args[3] = jiffy_since;
2214 	count_attr = nla_reserve(skb, TCA_ROOT_COUNT, sizeof(u32));
2215 	if (!count_attr)
2216 		goto out_module_put;
2217 
2218 	nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
2219 	if (nest == NULL)
2220 		goto out_module_put;
2221 
2222 	ret = __tcf_generic_walker(net, skb, cb, RTM_GETACTION, a_o, NULL);
2223 	if (ret < 0)
2224 		goto out_module_put;
2225 
2226 	if (ret > 0) {
2227 		nla_nest_end(skb, nest);
2228 		ret = skb->len;
2229 		act_count = cb->args[1];
2230 		memcpy(nla_data(count_attr), &act_count, sizeof(u32));
2231 		cb->args[1] = 0;
2232 	} else
2233 		nlmsg_trim(skb, b);
2234 
2235 	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
2236 	if (NETLINK_CB(cb->skb).portid && ret)
2237 		nlh->nlmsg_flags |= NLM_F_MULTI;
2238 	module_put(a_o->owner);
2239 	return skb->len;
2240 
2241 out_module_put:
2242 	module_put(a_o->owner);
2243 	nlmsg_trim(skb, b);
2244 	return skb->len;
2245 }
2246 
2247 static int __init tc_action_init(void)
2248 {
2249 	rtnl_register(PF_UNSPEC, RTM_NEWACTION, tc_ctl_action, NULL, 0);
2250 	rtnl_register(PF_UNSPEC, RTM_DELACTION, tc_ctl_action, NULL, 0);
2251 	rtnl_register(PF_UNSPEC, RTM_GETACTION, tc_ctl_action, tc_dump_action,
2252 		      0);
2253 
2254 	return 0;
2255 }
2256 
2257 subsys_initcall(tc_action_init);
2258