xref: /linux/net/sched/act_api.c (revision 7b16eb911091aae237a8673da94e4dfb9cd21d54)
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 tcf_chain *chain,
45 				       struct tcf_result *res)
46 {
47 	res->goto_tp = rcu_dereference_bh(chain->filter_chain);
48 }
49 
50 static void tcf_free_cookie_rcu(struct rcu_head *p)
51 {
52 	struct tc_cookie *cookie = container_of(p, struct tc_cookie, rcu);
53 
54 	kfree(cookie->data);
55 	kfree(cookie);
56 }
57 
58 static void tcf_set_action_cookie(struct tc_cookie __rcu **old_cookie,
59 				  struct tc_cookie *new_cookie)
60 {
61 	struct tc_cookie *old;
62 
63 	old = unrcu_pointer(xchg(old_cookie, RCU_INITIALIZER(new_cookie)));
64 	if (old)
65 		call_rcu(&old->rcu, tcf_free_cookie_rcu);
66 }
67 
68 int tcf_action_check_ctrlact(int action, struct tcf_proto *tp,
69 			     struct tcf_chain **newchain,
70 			     struct netlink_ext_ack *extack)
71 {
72 	int opcode = TC_ACT_EXT_OPCODE(action), ret = -EINVAL;
73 	u32 chain_index;
74 
75 	if (!opcode)
76 		ret = action > TC_ACT_VALUE_MAX ? -EINVAL : 0;
77 	else if (opcode <= TC_ACT_EXT_OPCODE_MAX || action == TC_ACT_UNSPEC)
78 		ret = 0;
79 	if (ret) {
80 		NL_SET_ERR_MSG(extack, "invalid control action");
81 		goto end;
82 	}
83 
84 	if (TC_ACT_EXT_CMP(action, TC_ACT_GOTO_CHAIN)) {
85 		chain_index = action & TC_ACT_EXT_VAL_MASK;
86 		if (!tp || !newchain) {
87 			ret = -EINVAL;
88 			NL_SET_ERR_MSG(extack,
89 				       "can't goto NULL proto/chain");
90 			goto end;
91 		}
92 		*newchain = tcf_chain_get_by_act(tp->chain->block, chain_index);
93 		if (!*newchain) {
94 			ret = -ENOMEM;
95 			NL_SET_ERR_MSG(extack,
96 				       "can't allocate goto_chain");
97 		}
98 	}
99 end:
100 	return ret;
101 }
102 EXPORT_SYMBOL(tcf_action_check_ctrlact);
103 
104 struct tcf_chain *tcf_action_set_ctrlact(struct tc_action *a, int action,
105 					 struct tcf_chain *goto_chain)
106 {
107 	a->tcfa_action = action;
108 	goto_chain = rcu_replace_pointer(a->goto_chain, goto_chain, 1);
109 	return goto_chain;
110 }
111 EXPORT_SYMBOL(tcf_action_set_ctrlact);
112 
113 static void free_tcf(struct tc_action *p)
114 {
115 	struct tcf_chain *chain = rcu_dereference_protected(p->goto_chain, 1);
116 
117 	free_percpu(p->cpu_bstats);
118 	free_percpu(p->cpu_bstats_hw);
119 	free_percpu(p->cpu_qstats);
120 
121 	tcf_set_action_cookie(&p->user_cookie, NULL);
122 	if (chain)
123 		tcf_chain_put_by_act(chain);
124 
125 	kfree_rcu(p, tcfa_rcu);
126 }
127 
128 static void offload_action_hw_count_set(struct tc_action *act,
129 					u32 hw_count)
130 {
131 	act->in_hw_count = hw_count;
132 }
133 
134 static void offload_action_hw_count_inc(struct tc_action *act,
135 					u32 hw_count)
136 {
137 	act->in_hw_count += hw_count;
138 }
139 
140 static void offload_action_hw_count_dec(struct tc_action *act,
141 					u32 hw_count)
142 {
143 	act->in_hw_count = act->in_hw_count > hw_count ?
144 			   act->in_hw_count - hw_count : 0;
145 }
146 
147 static unsigned int tcf_offload_act_num_actions_single(struct tc_action *act)
148 {
149 	unsigned int count;
150 
151 	if (is_tcf_pedit(act)) {
152 		spin_lock_bh(&act->tcfa_lock);
153 		count = tcf_pedit_nkeys_locked(act);
154 		spin_unlock_bh(&act->tcfa_lock);
155 		return count;
156 	}
157 	return 1;
158 }
159 
160 static bool tc_act_skip_hw(u32 flags)
161 {
162 	return (flags & TCA_ACT_FLAGS_SKIP_HW) ? true : false;
163 }
164 
165 static bool tc_act_skip_sw(u32 flags)
166 {
167 	return (flags & TCA_ACT_FLAGS_SKIP_SW) ? true : false;
168 }
169 
170 /* SKIP_HW and SKIP_SW are mutually exclusive flags. */
171 static bool tc_act_flags_valid(u32 flags)
172 {
173 	flags &= TCA_ACT_FLAGS_SKIP_HW | TCA_ACT_FLAGS_SKIP_SW;
174 
175 	return flags ^ (TCA_ACT_FLAGS_SKIP_HW | TCA_ACT_FLAGS_SKIP_SW);
176 }
177 
178 static int offload_action_init(struct flow_offload_action *fl_action,
179 			       struct tc_action *act,
180 			       enum offload_act_command  cmd,
181 			       struct netlink_ext_ack *extack)
182 {
183 	int err;
184 
185 	fl_action->extack = extack;
186 	fl_action->command = cmd;
187 	fl_action->index = act->tcfa_index;
188 	fl_action->cookie = (unsigned long)act;
189 
190 	if (act->ops->offload_act_setup) {
191 		spin_lock_bh(&act->tcfa_lock);
192 		err = act->ops->offload_act_setup(act, fl_action, NULL,
193 						  false, extack);
194 		spin_unlock_bh(&act->tcfa_lock);
195 		return err;
196 	}
197 
198 	return -EOPNOTSUPP;
199 }
200 
201 static int tcf_action_offload_cmd_ex(struct flow_offload_action *fl_act,
202 				     u32 *hw_count)
203 {
204 	int err;
205 
206 	err = flow_indr_dev_setup_offload(NULL, NULL, TC_SETUP_ACT,
207 					  fl_act, NULL, NULL);
208 	if (err < 0)
209 		return err;
210 
211 	if (hw_count)
212 		*hw_count = err;
213 
214 	return 0;
215 }
216 
217 static int tcf_action_offload_cmd_cb_ex(struct flow_offload_action *fl_act,
218 					u32 *hw_count,
219 					flow_indr_block_bind_cb_t *cb,
220 					void *cb_priv)
221 {
222 	int err;
223 
224 	err = cb(NULL, NULL, cb_priv, TC_SETUP_ACT, NULL, fl_act, NULL);
225 	if (err < 0)
226 		return err;
227 
228 	if (hw_count)
229 		*hw_count = 1;
230 
231 	return 0;
232 }
233 
234 static int tcf_action_offload_cmd(struct flow_offload_action *fl_act,
235 				  u32 *hw_count,
236 				  flow_indr_block_bind_cb_t *cb,
237 				  void *cb_priv)
238 {
239 	return cb ? tcf_action_offload_cmd_cb_ex(fl_act, hw_count,
240 						 cb, cb_priv) :
241 		    tcf_action_offload_cmd_ex(fl_act, hw_count);
242 }
243 
244 static int tcf_action_offload_add_ex(struct tc_action *action,
245 				     struct netlink_ext_ack *extack,
246 				     flow_indr_block_bind_cb_t *cb,
247 				     void *cb_priv)
248 {
249 	bool skip_sw = tc_act_skip_sw(action->tcfa_flags);
250 	struct tc_action *actions[TCA_ACT_MAX_PRIO] = {
251 		[0] = action,
252 	};
253 	struct flow_offload_action *fl_action;
254 	u32 in_hw_count = 0;
255 	int num, err = 0;
256 
257 	if (tc_act_skip_hw(action->tcfa_flags))
258 		return 0;
259 
260 	num = tcf_offload_act_num_actions_single(action);
261 	fl_action = offload_action_alloc(num);
262 	if (!fl_action)
263 		return -ENOMEM;
264 
265 	err = offload_action_init(fl_action, action, FLOW_ACT_REPLACE, extack);
266 	if (err)
267 		goto fl_err;
268 
269 	err = tc_setup_action(&fl_action->action, actions, 0, extack);
270 	if (err) {
271 		NL_SET_ERR_MSG_MOD(extack,
272 				   "Failed to setup tc actions for offload");
273 		goto fl_err;
274 	}
275 
276 	err = tcf_action_offload_cmd(fl_action, &in_hw_count, cb, cb_priv);
277 	if (!err)
278 		cb ? offload_action_hw_count_inc(action, in_hw_count) :
279 		     offload_action_hw_count_set(action, in_hw_count);
280 
281 	if (skip_sw && !tc_act_in_hw(action))
282 		err = -EINVAL;
283 
284 	tc_cleanup_offload_action(&fl_action->action);
285 
286 fl_err:
287 	kfree(fl_action);
288 
289 	return err;
290 }
291 
292 /* offload the tc action after it is inserted */
293 static int tcf_action_offload_add(struct tc_action *action,
294 				  struct netlink_ext_ack *extack)
295 {
296 	return tcf_action_offload_add_ex(action, extack, NULL, NULL);
297 }
298 
299 int tcf_action_update_hw_stats(struct tc_action *action)
300 {
301 	struct flow_offload_action fl_act = {};
302 	int err;
303 
304 	err = offload_action_init(&fl_act, action, FLOW_ACT_STATS, NULL);
305 	if (err)
306 		return err;
307 
308 	err = tcf_action_offload_cmd(&fl_act, NULL, NULL, NULL);
309 	if (!err) {
310 		preempt_disable();
311 		tcf_action_stats_update(action, fl_act.stats.bytes,
312 					fl_act.stats.pkts,
313 					fl_act.stats.drops,
314 					fl_act.stats.lastused,
315 					true);
316 		preempt_enable();
317 		action->used_hw_stats = fl_act.stats.used_hw_stats;
318 		action->used_hw_stats_valid = true;
319 	} else {
320 		return -EOPNOTSUPP;
321 	}
322 
323 	return 0;
324 }
325 EXPORT_SYMBOL(tcf_action_update_hw_stats);
326 
327 static int tcf_action_offload_del_ex(struct tc_action *action,
328 				     flow_indr_block_bind_cb_t *cb,
329 				     void *cb_priv)
330 {
331 	struct flow_offload_action fl_act = {};
332 	u32 in_hw_count = 0;
333 	int err = 0;
334 
335 	if (!tc_act_in_hw(action))
336 		return 0;
337 
338 	err = offload_action_init(&fl_act, action, FLOW_ACT_DESTROY, NULL);
339 	if (err)
340 		return err;
341 
342 	err = tcf_action_offload_cmd(&fl_act, &in_hw_count, cb, cb_priv);
343 	if (err < 0)
344 		return err;
345 
346 	if (!cb && action->in_hw_count != in_hw_count)
347 		return -EINVAL;
348 
349 	/* do not need to update hw state when deleting action */
350 	if (cb && in_hw_count)
351 		offload_action_hw_count_dec(action, in_hw_count);
352 
353 	return 0;
354 }
355 
356 static int tcf_action_offload_del(struct tc_action *action)
357 {
358 	return tcf_action_offload_del_ex(action, NULL, NULL);
359 }
360 
361 static void tcf_action_cleanup(struct tc_action *p)
362 {
363 	tcf_action_offload_del(p);
364 	if (p->ops->cleanup)
365 		p->ops->cleanup(p);
366 
367 	gen_kill_estimator(&p->tcfa_rate_est);
368 	free_tcf(p);
369 }
370 
371 static int __tcf_action_put(struct tc_action *p, bool bind)
372 {
373 	struct tcf_idrinfo *idrinfo = p->idrinfo;
374 
375 	mutex_lock(&idrinfo->lock);
376 	if (bind)
377 		atomic_dec(&p->tcfa_bindcnt);
378 	if (refcount_dec_and_test(&p->tcfa_refcnt)) {
379 		idr_remove(&idrinfo->action_idr, p->tcfa_index);
380 		mutex_unlock(&idrinfo->lock);
381 
382 		tcf_action_cleanup(p);
383 		return 1;
384 	}
385 
386 	mutex_unlock(&idrinfo->lock);
387 	return 0;
388 }
389 
390 static int __tcf_idr_release(struct tc_action *p, bool bind, bool strict)
391 {
392 	int ret = 0;
393 
394 	/* Release with strict==1 and bind==0 is only called through act API
395 	 * interface (classifiers always bind). Only case when action with
396 	 * positive reference count and zero bind count can exist is when it was
397 	 * also created with act API (unbinding last classifier will destroy the
398 	 * action if it was created by classifier). So only case when bind count
399 	 * can be changed after initial check is when unbound action is
400 	 * destroyed by act API while classifier binds to action with same id
401 	 * concurrently. This result either creation of new action(same behavior
402 	 * as before), or reusing existing action if concurrent process
403 	 * increments reference count before action is deleted. Both scenarios
404 	 * are acceptable.
405 	 */
406 	if (p) {
407 		if (!bind && strict && atomic_read(&p->tcfa_bindcnt) > 0)
408 			return -EPERM;
409 
410 		if (__tcf_action_put(p, bind))
411 			ret = ACT_P_DELETED;
412 	}
413 
414 	return ret;
415 }
416 
417 int tcf_idr_release(struct tc_action *a, bool bind)
418 {
419 	const struct tc_action_ops *ops = a->ops;
420 	int ret;
421 
422 	ret = __tcf_idr_release(a, bind, false);
423 	if (ret == ACT_P_DELETED)
424 		module_put(ops->owner);
425 	return ret;
426 }
427 EXPORT_SYMBOL(tcf_idr_release);
428 
429 static size_t tcf_action_shared_attrs_size(const struct tc_action *act)
430 {
431 	struct tc_cookie *user_cookie;
432 	u32 cookie_len = 0;
433 
434 	rcu_read_lock();
435 	user_cookie = rcu_dereference(act->user_cookie);
436 
437 	if (user_cookie)
438 		cookie_len = nla_total_size(user_cookie->len);
439 	rcu_read_unlock();
440 
441 	return  nla_total_size(0) /* action number nested */
442 		+ nla_total_size(IFNAMSIZ) /* TCA_ACT_KIND */
443 		+ cookie_len /* TCA_ACT_COOKIE */
444 		+ nla_total_size(sizeof(struct nla_bitfield32)) /* TCA_ACT_HW_STATS */
445 		/* TCA_ACT_USED_HW_STATS */
446 		+ nla_total_size(sizeof(struct nla_bitfield32))
447 		+ nla_total_size(sizeof(u32)) /* TCA_ACT_IN_HW_COUNT */
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_BASIC_HW */
453 		+ nla_total_size_64bit(sizeof(struct gnet_stats_basic))
454 		/* TCA_STATS_PKT64, emitted by both of the basic copies above */
455 		+ 2 * nla_total_size_64bit(sizeof(u64))
456 		/* TCA_STATS_RATE_EST */
457 		+ nla_total_size_64bit(sizeof(struct gnet_stats_rate_est))
458 		/* TCA_STATS_RATE_EST64 */
459 		+ nla_total_size_64bit(sizeof(struct gnet_stats_rate_est64))
460 		/* TCA_STATS_QUEUE */
461 		+ nla_total_size_64bit(sizeof(struct gnet_stats_queue))
462 		+ nla_total_size(0) /* TCA_ACT_OPTIONS nested */
463 		/* TCA_GACT_TM; actions dump their tcf_t with nla_put_64bit(),
464 		 * which may emit an extra NLA_PAD attribute.
465 		 */
466 		+ nla_total_size_64bit(sizeof(struct tcf_t));
467 }
468 
469 static size_t tcf_action_full_attrs_size(size_t sz)
470 {
471 	return NLMSG_HDRLEN                     /* struct nlmsghdr */
472 		+ sizeof(struct tcamsg)
473 		+ nla_total_size(0)             /* TCA_ACT_TAB nested */
474 		+ sz;
475 }
476 
477 static size_t tcf_action_fill_size(const struct tc_action *act)
478 {
479 	size_t sz = tcf_action_shared_attrs_size(act);
480 
481 	if (act->ops->get_fill_size)
482 		return act->ops->get_fill_size(act) + sz;
483 	return sz;
484 }
485 
486 static int
487 tcf_action_dump_terse(struct sk_buff *skb, struct tc_action *a, bool from_act)
488 {
489 	unsigned char *b = skb_tail_pointer(skb);
490 	struct tc_cookie *cookie;
491 
492 	if (nla_put_string(skb, TCA_ACT_KIND, a->ops->kind))
493 		goto nla_put_failure;
494 	if (tcf_action_copy_stats(skb, a, 0))
495 		goto nla_put_failure;
496 	if (from_act && nla_put_u32(skb, TCA_ACT_INDEX, a->tcfa_index))
497 		goto nla_put_failure;
498 
499 	rcu_read_lock();
500 	cookie = rcu_dereference(a->user_cookie);
501 	if (cookie) {
502 		if (nla_put(skb, TCA_ACT_COOKIE, cookie->len, cookie->data)) {
503 			rcu_read_unlock();
504 			goto nla_put_failure;
505 		}
506 	}
507 	rcu_read_unlock();
508 
509 	return 0;
510 
511 nla_put_failure:
512 	nlmsg_trim(skb, b);
513 	return -1;
514 }
515 
516 static int
517 tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
518 {
519 	unsigned char *b = skb_tail_pointer(skb);
520 	struct nlattr *nest;
521 	int err = -EINVAL;
522 	u32 flags;
523 
524 	if (tcf_action_dump_terse(skb, a, false))
525 		goto nla_put_failure;
526 
527 	if (a->hw_stats != TCA_ACT_HW_STATS_ANY &&
528 	    nla_put_bitfield32(skb, TCA_ACT_HW_STATS,
529 			       a->hw_stats, TCA_ACT_HW_STATS_ANY))
530 		goto nla_put_failure;
531 
532 	if (a->used_hw_stats_valid &&
533 	    nla_put_bitfield32(skb, TCA_ACT_USED_HW_STATS,
534 			       a->used_hw_stats, TCA_ACT_HW_STATS_ANY))
535 		goto nla_put_failure;
536 
537 	flags = a->tcfa_flags & TCA_ACT_FLAGS_USER_MASK;
538 	if (flags &&
539 	    nla_put_bitfield32(skb, TCA_ACT_FLAGS,
540 			       flags, flags))
541 		goto nla_put_failure;
542 
543 	if (nla_put_u32(skb, TCA_ACT_IN_HW_COUNT, a->in_hw_count))
544 		goto nla_put_failure;
545 
546 	nest = nla_nest_start_noflag(skb, TCA_ACT_OPTIONS);
547 	if (nest == NULL)
548 		goto nla_put_failure;
549 	err = tcf_action_dump_old(skb, a, bind, ref);
550 	if (err > 0) {
551 		nla_nest_end(skb, nest);
552 		return err;
553 	}
554 
555 nla_put_failure:
556 	nlmsg_trim(skb, b);
557 	return -1;
558 }
559 
560 static int tcf_dump_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb,
561 			   struct netlink_callback *cb)
562 {
563 	int err = 0, index = -1, s_i = 0, n_i = 0;
564 	u32 act_flags = cb->args[2];
565 	unsigned long jiffy_since = cb->args[3];
566 	struct nlattr *nest;
567 	struct idr *idr = &idrinfo->action_idr;
568 	struct tc_action *p;
569 	unsigned long id = 1;
570 	unsigned long tmp;
571 
572 	mutex_lock(&idrinfo->lock);
573 
574 	s_i = cb->args[0];
575 
576 	idr_for_each_entry_ul(idr, p, tmp, id) {
577 		index++;
578 		if (index < s_i)
579 			continue;
580 		if (IS_ERR(p))
581 			continue;
582 
583 		if (jiffy_since &&
584 		    time_after(jiffy_since,
585 			       (unsigned long)p->tcfa_tm.lastuse))
586 			continue;
587 
588 		tcf_action_update_hw_stats(p);
589 
590 		nest = nla_nest_start_noflag(skb, n_i);
591 		if (!nest) {
592 			index--;
593 			goto nla_put_failure;
594 		}
595 		err = (act_flags & TCA_ACT_FLAG_TERSE_DUMP) ?
596 			tcf_action_dump_terse(skb, p, true) :
597 			tcf_action_dump_1(skb, p, 0, 0);
598 		if (err < 0) {
599 			index--;
600 			nlmsg_trim(skb, nest);
601 			goto done;
602 		}
603 		nla_nest_end(skb, nest);
604 		n_i++;
605 		if (!(act_flags & TCA_ACT_FLAG_LARGE_DUMP_ON) &&
606 		    n_i >= TCA_ACT_MAX_PRIO)
607 			goto done;
608 	}
609 done:
610 	if (index >= 0)
611 		cb->args[0] = index + 1;
612 
613 	mutex_unlock(&idrinfo->lock);
614 	if (n_i) {
615 		if (act_flags & TCA_ACT_FLAG_LARGE_DUMP_ON)
616 			cb->args[1] = n_i;
617 	}
618 	return n_i;
619 
620 nla_put_failure:
621 	nla_nest_cancel(skb, nest);
622 	goto done;
623 }
624 
625 static int tcf_idr_release_unsafe(struct tc_action *p)
626 {
627 	if (atomic_read(&p->tcfa_bindcnt) > 0)
628 		return -EPERM;
629 
630 	if (refcount_dec_and_test(&p->tcfa_refcnt)) {
631 		idr_remove(&p->idrinfo->action_idr, p->tcfa_index);
632 		tcf_action_cleanup(p);
633 		return ACT_P_DELETED;
634 	}
635 
636 	return 0;
637 }
638 
639 static int tcf_del_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb,
640 			  const struct tc_action_ops *ops,
641 			  struct netlink_ext_ack *extack)
642 {
643 	struct nlattr *nest;
644 	int n_i = 0;
645 	int ret = -EINVAL;
646 	struct idr *idr = &idrinfo->action_idr;
647 	struct tc_action *p;
648 	unsigned long id = 1;
649 	unsigned long tmp;
650 
651 	nest = nla_nest_start_noflag(skb, 0);
652 	if (nest == NULL)
653 		goto nla_put_failure;
654 	if (nla_put_string(skb, TCA_ACT_KIND, ops->kind))
655 		goto nla_put_failure;
656 
657 	ret = 0;
658 	mutex_lock(&idrinfo->lock);
659 	idr_for_each_entry_ul(idr, p, tmp, id) {
660 		if (IS_ERR(p))
661 			continue;
662 		ret = tcf_idr_release_unsafe(p);
663 		if (ret == ACT_P_DELETED)
664 			module_put(ops->owner);
665 		else if (ret < 0)
666 			break;
667 		n_i++;
668 	}
669 	mutex_unlock(&idrinfo->lock);
670 	if (ret < 0) {
671 		if (n_i)
672 			NL_SET_ERR_MSG(extack, "Unable to flush all TC actions");
673 		else
674 			goto nla_put_failure;
675 	}
676 
677 	ret = nla_put_u32(skb, TCA_FCNT, n_i);
678 	if (ret)
679 		goto nla_put_failure;
680 	nla_nest_end(skb, nest);
681 
682 	return n_i;
683 nla_put_failure:
684 	nla_nest_cancel(skb, nest);
685 	return ret;
686 }
687 
688 int tcf_generic_walker(struct tc_action_net *tn, struct sk_buff *skb,
689 		       struct netlink_callback *cb, int type,
690 		       const struct tc_action_ops *ops,
691 		       struct netlink_ext_ack *extack)
692 {
693 	struct tcf_idrinfo *idrinfo = tn->idrinfo;
694 
695 	if (type == RTM_DELACTION) {
696 		return tcf_del_walker(idrinfo, skb, ops, extack);
697 	} else if (type == RTM_GETACTION) {
698 		return tcf_dump_walker(idrinfo, skb, cb);
699 	} else {
700 		WARN(1, "tcf_generic_walker: unknown command %d\n", type);
701 		NL_SET_ERR_MSG(extack, "tcf_generic_walker: unknown command");
702 		return -EINVAL;
703 	}
704 }
705 EXPORT_SYMBOL(tcf_generic_walker);
706 
707 int tcf_idr_search(struct tc_action_net *tn, struct tc_action **a, u32 index)
708 {
709 	struct tcf_idrinfo *idrinfo = tn->idrinfo;
710 	struct tc_action *p;
711 
712 	mutex_lock(&idrinfo->lock);
713 	p = idr_find(&idrinfo->action_idr, index);
714 	if (IS_ERR(p))
715 		p = NULL;
716 	else if (p)
717 		refcount_inc(&p->tcfa_refcnt);
718 	mutex_unlock(&idrinfo->lock);
719 
720 	if (p) {
721 		*a = p;
722 		return true;
723 	}
724 	return false;
725 }
726 EXPORT_SYMBOL(tcf_idr_search);
727 
728 static int __tcf_generic_walker(struct net *net, struct sk_buff *skb,
729 				struct netlink_callback *cb, int type,
730 				const struct tc_action_ops *ops,
731 				struct netlink_ext_ack *extack)
732 {
733 	struct tc_action_net *tn = net_generic(net, ops->net_id);
734 
735 	if (unlikely(ops->walk))
736 		return ops->walk(net, skb, cb, type, ops, extack);
737 
738 	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
739 }
740 
741 static int __tcf_idr_search(struct net *net,
742 			    const struct tc_action_ops *ops,
743 			    struct tc_action **a, u32 index)
744 {
745 	struct tc_action_net *tn = net_generic(net, ops->net_id);
746 
747 	if (unlikely(ops->lookup))
748 		return ops->lookup(net, a, index);
749 
750 	return tcf_idr_search(tn, a, index);
751 }
752 
753 static int tcf_idr_delete_index(struct tcf_idrinfo *idrinfo, u32 index)
754 {
755 	struct tc_action *p;
756 	int ret = 0;
757 
758 	mutex_lock(&idrinfo->lock);
759 	p = idr_find(&idrinfo->action_idr, index);
760 	if (IS_ERR_OR_NULL(p)) {
761 		mutex_unlock(&idrinfo->lock);
762 		return -ENOENT;
763 	}
764 
765 	if (!atomic_read(&p->tcfa_bindcnt)) {
766 		if (refcount_dec_and_test(&p->tcfa_refcnt)) {
767 			struct module *owner = p->ops->owner;
768 
769 			WARN_ON(p != idr_remove(&idrinfo->action_idr,
770 						p->tcfa_index));
771 			mutex_unlock(&idrinfo->lock);
772 
773 			tcf_action_cleanup(p);
774 			module_put(owner);
775 			return 0;
776 		}
777 		ret = 0;
778 	} else {
779 		ret = -EPERM;
780 	}
781 
782 	mutex_unlock(&idrinfo->lock);
783 	return ret;
784 }
785 
786 int tcf_idr_create(struct tc_action_net *tn, u32 index, struct nlattr *est,
787 		   struct tc_action **a, const struct tc_action_ops *ops,
788 		   int bind, bool cpustats, u32 flags)
789 {
790 	struct tc_action *p = kzalloc(ops->size, GFP_KERNEL);
791 	struct tcf_idrinfo *idrinfo = tn->idrinfo;
792 	int err = -ENOMEM;
793 
794 	if (unlikely(!p))
795 		return -ENOMEM;
796 	refcount_set(&p->tcfa_refcnt, 1);
797 	if (bind)
798 		atomic_set(&p->tcfa_bindcnt, 1);
799 
800 	if (cpustats) {
801 		p->cpu_bstats = netdev_alloc_pcpu_stats(struct gnet_stats_basic_sync);
802 		if (!p->cpu_bstats)
803 			goto err1;
804 		p->cpu_bstats_hw = netdev_alloc_pcpu_stats(struct gnet_stats_basic_sync);
805 		if (!p->cpu_bstats_hw)
806 			goto err2;
807 		p->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
808 		if (!p->cpu_qstats)
809 			goto err3;
810 	}
811 	gnet_stats_basic_sync_init(&p->tcfa_bstats);
812 	gnet_stats_basic_sync_init(&p->tcfa_bstats_hw);
813 	spin_lock_init(&p->tcfa_lock);
814 	p->tcfa_index = index;
815 	p->tcfa_tm.install = jiffies;
816 	p->tcfa_tm.lastuse = jiffies;
817 	p->tcfa_tm.firstuse = 0;
818 	p->tcfa_flags = flags;
819 	if (est) {
820 		err = gen_new_estimator(&p->tcfa_bstats, p->cpu_bstats,
821 					&p->tcfa_rate_est,
822 					&p->tcfa_lock, false, est);
823 		if (err)
824 			goto err4;
825 	}
826 
827 	p->idrinfo = idrinfo;
828 	__module_get(ops->owner);
829 	p->ops = ops;
830 	*a = p;
831 	return 0;
832 err4:
833 	free_percpu(p->cpu_qstats);
834 err3:
835 	free_percpu(p->cpu_bstats_hw);
836 err2:
837 	free_percpu(p->cpu_bstats);
838 err1:
839 	kfree(p);
840 	return err;
841 }
842 EXPORT_SYMBOL(tcf_idr_create);
843 
844 int tcf_idr_create_from_flags(struct tc_action_net *tn, u32 index,
845 			      struct nlattr *est, struct tc_action **a,
846 			      const struct tc_action_ops *ops, int bind,
847 			      u32 flags)
848 {
849 	/* Set cpustats according to actions flags. */
850 	return tcf_idr_create(tn, index, est, a, ops, bind,
851 			      !(flags & TCA_ACT_FLAGS_NO_PERCPU_STATS), flags);
852 }
853 EXPORT_SYMBOL(tcf_idr_create_from_flags);
854 
855 /* Cleanup idr index that was allocated but not initialized. */
856 
857 void tcf_idr_cleanup(struct tc_action_net *tn, u32 index)
858 {
859 	struct tcf_idrinfo *idrinfo = tn->idrinfo;
860 
861 	mutex_lock(&idrinfo->lock);
862 	/* Remove ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */
863 	WARN_ON(!IS_ERR(idr_remove(&idrinfo->action_idr, index)));
864 	mutex_unlock(&idrinfo->lock);
865 }
866 EXPORT_SYMBOL(tcf_idr_cleanup);
867 
868 /* Check if action with specified index exists. If actions is found, increments
869  * its reference and bind counters, and return 1. Otherwise insert temporary
870  * error pointer (to prevent concurrent users from inserting actions with same
871  * index) and return 0.
872  *
873  * May return -EAGAIN for binding actions in case of a parallel add/delete on
874  * the requested index.
875  */
876 
877 int tcf_idr_check_alloc(struct tc_action_net *tn, u32 *index,
878 			struct tc_action **a, int bind)
879 {
880 	struct tcf_idrinfo *idrinfo = tn->idrinfo;
881 	struct tc_action *p;
882 	int ret;
883 	u32 max;
884 
885 	if (*index) {
886 		rcu_read_lock();
887 		p = idr_find(&idrinfo->action_idr, *index);
888 
889 		if (IS_ERR(p)) {
890 			/* This means that another process allocated
891 			 * index but did not assign the pointer yet.
892 			 */
893 			rcu_read_unlock();
894 			return -EAGAIN;
895 		}
896 
897 		if (!p) {
898 			/* Empty slot, try to allocate it */
899 			max = *index;
900 			rcu_read_unlock();
901 			goto new;
902 		}
903 
904 		if (!refcount_inc_not_zero(&p->tcfa_refcnt)) {
905 			/* Action was deleted in parallel */
906 			rcu_read_unlock();
907 			return -EAGAIN;
908 		}
909 
910 		if (bind)
911 			atomic_inc(&p->tcfa_bindcnt);
912 		*a = p;
913 
914 		rcu_read_unlock();
915 
916 		return 1;
917 	} else {
918 		/* Find a slot */
919 		*index = 1;
920 		max = UINT_MAX;
921 	}
922 
923 new:
924 	*a = NULL;
925 
926 	mutex_lock(&idrinfo->lock);
927 	ret = idr_alloc_u32(&idrinfo->action_idr, ERR_PTR(-EBUSY), index, max,
928 			    GFP_KERNEL);
929 	mutex_unlock(&idrinfo->lock);
930 
931 	/* N binds raced for action allocation,
932 	 * retry for all the ones that failed.
933 	 */
934 	if (ret == -ENOSPC && *index == max)
935 		ret = -EAGAIN;
936 
937 	return ret;
938 }
939 EXPORT_SYMBOL(tcf_idr_check_alloc);
940 
941 void tcf_idrinfo_destroy(const struct tc_action_ops *ops,
942 			 struct tcf_idrinfo *idrinfo)
943 {
944 	struct idr *idr = &idrinfo->action_idr;
945 	bool mutex_taken = false;
946 	struct tc_action *p;
947 	unsigned long id = 1;
948 	unsigned long tmp;
949 	int ret;
950 
951 	idr_for_each_entry_ul(idr, p, tmp, id) {
952 		if (IS_ERR(p))
953 			continue;
954 		if (tc_act_in_hw(p) && !mutex_taken) {
955 			rtnl_lock();
956 			mutex_taken = true;
957 		}
958 		ret = __tcf_idr_release(p, false, true);
959 		if (ret == ACT_P_DELETED)
960 			module_put(ops->owner);
961 		else if (ret < 0)
962 			return;
963 	}
964 	if (mutex_taken)
965 		rtnl_unlock();
966 	idr_destroy(&idrinfo->action_idr);
967 }
968 EXPORT_SYMBOL(tcf_idrinfo_destroy);
969 
970 static LIST_HEAD(act_base);
971 static DEFINE_RWLOCK(act_mod_lock);
972 /* since act ops id is stored in pernet subsystem list,
973  * then there is no way to walk through only all the action
974  * subsystem, so we keep tc action pernet ops id for
975  * reoffload to walk through.
976  */
977 static LIST_HEAD(act_pernet_id_list);
978 static DEFINE_MUTEX(act_id_mutex);
979 struct tc_act_pernet_id {
980 	struct list_head list;
981 	unsigned int id;
982 };
983 
984 static int tcf_pernet_add_id_list(unsigned int id)
985 {
986 	struct tc_act_pernet_id *id_ptr;
987 	int ret = 0;
988 
989 	mutex_lock(&act_id_mutex);
990 	list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
991 		if (id_ptr->id == id) {
992 			ret = -EEXIST;
993 			goto err_out;
994 		}
995 	}
996 
997 	id_ptr = kzalloc_obj(*id_ptr);
998 	if (!id_ptr) {
999 		ret = -ENOMEM;
1000 		goto err_out;
1001 	}
1002 	id_ptr->id = id;
1003 
1004 	list_add_tail(&id_ptr->list, &act_pernet_id_list);
1005 
1006 err_out:
1007 	mutex_unlock(&act_id_mutex);
1008 	return ret;
1009 }
1010 
1011 static void tcf_pernet_del_id_list(unsigned int id)
1012 {
1013 	struct tc_act_pernet_id *id_ptr;
1014 
1015 	mutex_lock(&act_id_mutex);
1016 	list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
1017 		if (id_ptr->id == id) {
1018 			list_del(&id_ptr->list);
1019 			kfree(id_ptr);
1020 			break;
1021 		}
1022 	}
1023 	mutex_unlock(&act_id_mutex);
1024 }
1025 
1026 int tcf_register_action(struct tc_action_ops *act,
1027 			struct pernet_operations *ops)
1028 {
1029 	struct tc_action_ops *a;
1030 	int ret;
1031 
1032 	if (!act->act || !act->dump || !act->init)
1033 		return -EINVAL;
1034 
1035 	/* We have to register pernet ops before making the action ops visible,
1036 	 * otherwise tcf_action_init_1() could get a partially initialized
1037 	 * netns.
1038 	 */
1039 	ret = register_pernet_subsys(ops);
1040 	if (ret)
1041 		return ret;
1042 
1043 	if (ops->id) {
1044 		ret = tcf_pernet_add_id_list(*ops->id);
1045 		if (ret)
1046 			goto err_id;
1047 	}
1048 
1049 	write_lock(&act_mod_lock);
1050 	list_for_each_entry(a, &act_base, head) {
1051 		if (act->id == a->id || (strcmp(act->kind, a->kind) == 0)) {
1052 			ret = -EEXIST;
1053 			goto err_out;
1054 		}
1055 	}
1056 	list_add_tail(&act->head, &act_base);
1057 	write_unlock(&act_mod_lock);
1058 
1059 	return 0;
1060 
1061 err_out:
1062 	write_unlock(&act_mod_lock);
1063 	if (ops->id)
1064 		tcf_pernet_del_id_list(*ops->id);
1065 err_id:
1066 	unregister_pernet_subsys(ops);
1067 	return ret;
1068 }
1069 EXPORT_SYMBOL(tcf_register_action);
1070 
1071 int tcf_unregister_action(struct tc_action_ops *act,
1072 			  struct pernet_operations *ops)
1073 {
1074 	struct tc_action_ops *a;
1075 	int err = -ENOENT;
1076 
1077 	write_lock(&act_mod_lock);
1078 	list_for_each_entry(a, &act_base, head) {
1079 		if (a == act) {
1080 			list_del(&act->head);
1081 			err = 0;
1082 			break;
1083 		}
1084 	}
1085 	write_unlock(&act_mod_lock);
1086 	if (!err) {
1087 		unregister_pernet_subsys(ops);
1088 		if (ops->id)
1089 			tcf_pernet_del_id_list(*ops->id);
1090 	}
1091 	return err;
1092 }
1093 EXPORT_SYMBOL(tcf_unregister_action);
1094 
1095 /* lookup by name */
1096 static struct tc_action_ops *tc_lookup_action_n(char *kind)
1097 {
1098 	struct tc_action_ops *a, *res = NULL;
1099 
1100 	if (kind) {
1101 		read_lock(&act_mod_lock);
1102 		list_for_each_entry(a, &act_base, head) {
1103 			if (strcmp(kind, a->kind) == 0) {
1104 				if (try_module_get(a->owner))
1105 					res = a;
1106 				break;
1107 			}
1108 		}
1109 		read_unlock(&act_mod_lock);
1110 	}
1111 	return res;
1112 }
1113 
1114 /* lookup by nlattr */
1115 static struct tc_action_ops *tc_lookup_action(struct nlattr *kind)
1116 {
1117 	struct tc_action_ops *a, *res = NULL;
1118 
1119 	if (kind) {
1120 		read_lock(&act_mod_lock);
1121 		list_for_each_entry(a, &act_base, head) {
1122 			if (nla_strcmp(kind, a->kind) == 0) {
1123 				if (try_module_get(a->owner))
1124 					res = a;
1125 				break;
1126 			}
1127 		}
1128 		read_unlock(&act_mod_lock);
1129 	}
1130 	return res;
1131 }
1132 
1133 /*TCA_ACT_MAX_PRIO is 32, there count up to 32 */
1134 #define TCA_ACT_MAX_PRIO_MASK 0x1FF
1135 int tcf_action_exec(struct sk_buff *skb, struct tc_action **actions,
1136 		    int nr_actions, struct tcf_result *res)
1137 {
1138 	u32 jmp_prgcnt = 0;
1139 	u32 jmp_ttl = TCA_ACT_MAX_PRIO; /*matches actions per filter */
1140 	int i;
1141 	int ret = TC_ACT_OK;
1142 
1143 	if (skb_skip_tc_classify(skb))
1144 		return TC_ACT_OK;
1145 
1146 restart_act_graph:
1147 	for (i = 0; i < nr_actions; i++) {
1148 		const struct tc_action *a = actions[i];
1149 		int repeat_ttl;
1150 
1151 		if (jmp_prgcnt > 0) {
1152 			jmp_prgcnt -= 1;
1153 			continue;
1154 		}
1155 
1156 		if (tc_act_skip_sw(a->tcfa_flags))
1157 			continue;
1158 
1159 		repeat_ttl = 32;
1160 repeat:
1161 		ret = tc_act(skb, a, res);
1162 		if (unlikely(ret == TC_ACT_REPEAT)) {
1163 			if (--repeat_ttl != 0)
1164 				goto repeat;
1165 			/* suspicious opcode, stop pipeline */
1166 			net_warn_ratelimited("TC_ACT_REPEAT abuse ?\n");
1167 			return TC_ACT_OK;
1168 		}
1169 		if (TC_ACT_EXT_CMP(ret, TC_ACT_JUMP)) {
1170 			jmp_prgcnt = ret & TCA_ACT_MAX_PRIO_MASK;
1171 			if (!jmp_prgcnt || (jmp_prgcnt > nr_actions)) {
1172 				/* faulty opcode, stop pipeline */
1173 				return TC_ACT_OK;
1174 			} else {
1175 				jmp_ttl -= 1;
1176 				if (jmp_ttl > 0)
1177 					goto restart_act_graph;
1178 				else /* faulty graph, stop pipeline */
1179 					return TC_ACT_OK;
1180 			}
1181 		} else if (TC_ACT_EXT_CMP(ret, TC_ACT_GOTO_CHAIN)) {
1182 			struct tcf_chain *chain = rcu_dereference_bh(a->goto_chain);
1183 
1184 			if (unlikely(!chain)) {
1185 				tcf_set_drop_reason(skb,
1186 						    SKB_DROP_REASON_TC_CHAIN_NOTFOUND);
1187 				return TC_ACT_SHOT;
1188 			}
1189 			tcf_action_goto_chain_exec(chain, res);
1190 		}
1191 
1192 		if (ret != TC_ACT_PIPE)
1193 			break;
1194 	}
1195 
1196 	return ret;
1197 }
1198 EXPORT_SYMBOL(tcf_action_exec);
1199 
1200 int tcf_action_destroy(struct tc_action *actions[], int bind)
1201 {
1202 	struct tc_action *a;
1203 	int ret = 0, i;
1204 
1205 	tcf_act_for_each_action(i, a, actions) {
1206 		actions[i] = NULL;
1207 		/* Drop our reference even if the action is still bound to a filter. */
1208 		ret = tcf_idr_release(a, bind);
1209 	}
1210 	return ret;
1211 }
1212 
1213 static int tcf_action_put(struct tc_action *p)
1214 {
1215 	return __tcf_action_put(p, false);
1216 }
1217 
1218 static void tcf_action_put_many(struct tc_action *actions[])
1219 {
1220 	int i;
1221 
1222 	/* Deletion may have cleared entries before failing. */
1223 	for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
1224 		struct tc_action *a = actions[i];
1225 		const struct tc_action_ops *ops;
1226 
1227 		if (!a)
1228 			continue;
1229 		ops = a->ops;
1230 		if (tcf_action_put(a))
1231 			module_put(ops->owner);
1232 	}
1233 }
1234 
1235 static void tca_put_bound_many(struct tc_action *actions[], int init_res[])
1236 {
1237 	struct tc_action *a;
1238 	int i;
1239 
1240 	tcf_act_for_each_action(i, a, actions) {
1241 		const struct tc_action_ops *ops = a->ops;
1242 
1243 		if (init_res[i] == ACT_P_CREATED)
1244 			continue;
1245 
1246 		if (tcf_action_put(a))
1247 			module_put(ops->owner);
1248 	}
1249 }
1250 
1251 int
1252 tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
1253 {
1254 	return a->ops->dump(skb, a, bind, ref);
1255 }
1256 
1257 int tcf_action_dump(struct sk_buff *skb, struct tc_action *actions[],
1258 		    int bind, int ref, bool terse)
1259 {
1260 	struct tc_action *a;
1261 	int err = -EINVAL, i;
1262 	struct nlattr *nest;
1263 
1264 	tcf_act_for_each_action(i, a, actions) {
1265 		nest = nla_nest_start_noflag(skb, i + 1);
1266 		if (nest == NULL)
1267 			goto nla_put_failure;
1268 		err = terse ? tcf_action_dump_terse(skb, a, false) :
1269 			tcf_action_dump_1(skb, a, bind, ref);
1270 		if (err < 0)
1271 			goto errout;
1272 		nla_nest_end(skb, nest);
1273 	}
1274 
1275 	return 0;
1276 
1277 nla_put_failure:
1278 	err = -EINVAL;
1279 errout:
1280 	nla_nest_cancel(skb, nest);
1281 	return err;
1282 }
1283 
1284 static struct tc_cookie *nla_memdup_cookie(struct nlattr **tb)
1285 {
1286 	struct tc_cookie *c = kzalloc_obj(*c);
1287 	if (!c)
1288 		return NULL;
1289 
1290 	c->data = nla_memdup(tb[TCA_ACT_COOKIE], GFP_KERNEL);
1291 	if (!c->data) {
1292 		kfree(c);
1293 		return NULL;
1294 	}
1295 	c->len = nla_len(tb[TCA_ACT_COOKIE]);
1296 
1297 	return c;
1298 }
1299 
1300 static u8 tcf_action_hw_stats_get(struct nlattr *hw_stats_attr)
1301 {
1302 	struct nla_bitfield32 hw_stats_bf;
1303 
1304 	/* If the user did not pass the attr, that means he does
1305 	 * not care about the type. Return "any" in that case
1306 	 * which is setting on all supported types.
1307 	 */
1308 	if (!hw_stats_attr)
1309 		return TCA_ACT_HW_STATS_ANY;
1310 	hw_stats_bf = nla_get_bitfield32(hw_stats_attr);
1311 	return hw_stats_bf.value;
1312 }
1313 
1314 static const struct nla_policy tcf_action_policy[TCA_ACT_MAX + 1] = {
1315 	[TCA_ACT_KIND]		= { .type = NLA_STRING },
1316 	[TCA_ACT_INDEX]		= { .type = NLA_U32 },
1317 	[TCA_ACT_COOKIE]	= { .type = NLA_BINARY,
1318 				    .len = TC_COOKIE_MAX_SIZE },
1319 	[TCA_ACT_OPTIONS]	= { .type = NLA_NESTED },
1320 	[TCA_ACT_FLAGS]		= NLA_POLICY_BITFIELD32(TCA_ACT_FLAGS_NO_PERCPU_STATS |
1321 							TCA_ACT_FLAGS_SKIP_HW |
1322 							TCA_ACT_FLAGS_SKIP_SW),
1323 	[TCA_ACT_HW_STATS]	= NLA_POLICY_BITFIELD32(TCA_ACT_HW_STATS_ANY),
1324 };
1325 
1326 void tcf_idr_insert_many(struct tc_action *actions[], int init_res[])
1327 {
1328 	struct tc_action *a;
1329 	int i;
1330 
1331 	tcf_act_for_each_action(i, a, actions) {
1332 		struct tcf_idrinfo *idrinfo;
1333 
1334 		if (init_res[i] == ACT_P_BOUND)
1335 			continue;
1336 
1337 		idrinfo = a->idrinfo;
1338 		mutex_lock(&idrinfo->lock);
1339 		/* Replace ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */
1340 		idr_replace(&idrinfo->action_idr, a, a->tcfa_index);
1341 		mutex_unlock(&idrinfo->lock);
1342 	}
1343 }
1344 
1345 struct tc_action_ops *tc_action_load_ops(struct nlattr *nla, u32 flags,
1346 					 struct netlink_ext_ack *extack)
1347 {
1348 	bool police = flags & TCA_ACT_FLAGS_POLICE;
1349 	struct nlattr *tb[TCA_ACT_MAX + 1];
1350 	struct tc_action_ops *a_o;
1351 	char act_name[IFNAMSIZ];
1352 	struct nlattr *kind;
1353 	int err;
1354 
1355 	if (!police) {
1356 		err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1357 						  tcf_action_policy, extack);
1358 		if (err < 0)
1359 			return ERR_PTR(err);
1360 		err = -EINVAL;
1361 		kind = tb[TCA_ACT_KIND];
1362 		if (!kind) {
1363 			NL_SET_ERR_MSG(extack, "TC action kind must be specified");
1364 			return ERR_PTR(err);
1365 		}
1366 		if (nla_strscpy(act_name, kind, IFNAMSIZ) < 0) {
1367 			NL_SET_ERR_MSG(extack, "TC action name too long");
1368 			return ERR_PTR(err);
1369 		}
1370 	} else {
1371 		if (strscpy(act_name, "police", IFNAMSIZ) < 0) {
1372 			NL_SET_ERR_MSG(extack, "TC action name too long");
1373 			return ERR_PTR(-EINVAL);
1374 		}
1375 	}
1376 
1377 	a_o = tc_lookup_action_n(act_name);
1378 	if (a_o == NULL) {
1379 #ifdef CONFIG_MODULES
1380 		bool rtnl_held = !(flags & TCA_ACT_FLAGS_NO_RTNL);
1381 
1382 		if (rtnl_held)
1383 			rtnl_unlock();
1384 		request_module(NET_ACT_ALIAS_PREFIX "%s", act_name);
1385 		if (rtnl_held)
1386 			rtnl_lock();
1387 
1388 		a_o = tc_lookup_action_n(act_name);
1389 
1390 		/* We dropped the RTNL semaphore in order to
1391 		 * perform the module load.  So, even if we
1392 		 * succeeded in loading the module we have to
1393 		 * tell the caller to replay the request.  We
1394 		 * indicate this using -EAGAIN.
1395 		 */
1396 		if (a_o != NULL) {
1397 			module_put(a_o->owner);
1398 			return ERR_PTR(-EAGAIN);
1399 		}
1400 #endif
1401 		NL_SET_ERR_MSG(extack, "Failed to load TC action module");
1402 		return ERR_PTR(-ENOENT);
1403 	}
1404 
1405 	return a_o;
1406 }
1407 
1408 struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
1409 				    struct nlattr *nla, struct nlattr *est,
1410 				    struct tc_action_ops *a_o, int *init_res,
1411 				    u32 flags, struct netlink_ext_ack *extack)
1412 {
1413 	bool police = flags & TCA_ACT_FLAGS_POLICE;
1414 	struct nla_bitfield32 userflags = { 0, 0 };
1415 	struct tc_cookie *user_cookie = NULL;
1416 	u8 hw_stats = TCA_ACT_HW_STATS_ANY;
1417 	struct nlattr *tb[TCA_ACT_MAX + 1];
1418 	struct tc_action *a;
1419 	int err;
1420 
1421 	/* backward compatibility for policer */
1422 	if (!police) {
1423 		err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1424 						  tcf_action_policy, extack);
1425 		if (err < 0)
1426 			return ERR_PTR(err);
1427 		if (tb[TCA_ACT_COOKIE]) {
1428 			user_cookie = nla_memdup_cookie(tb);
1429 			if (!user_cookie) {
1430 				NL_SET_ERR_MSG(extack, "No memory to generate TC cookie");
1431 				err = -ENOMEM;
1432 				goto err_out;
1433 			}
1434 		}
1435 		hw_stats = tcf_action_hw_stats_get(tb[TCA_ACT_HW_STATS]);
1436 		if (tb[TCA_ACT_FLAGS]) {
1437 			userflags = nla_get_bitfield32(tb[TCA_ACT_FLAGS]);
1438 			if (!tc_act_flags_valid(userflags.value)) {
1439 				err = -EINVAL;
1440 				goto err_out;
1441 			}
1442 		}
1443 
1444 		err = a_o->init(net, tb[TCA_ACT_OPTIONS], est, &a, tp,
1445 				userflags.value | flags, extack);
1446 	} else {
1447 		err = a_o->init(net, nla, est, &a, tp, userflags.value | flags,
1448 				extack);
1449 	}
1450 	if (err < 0)
1451 		goto err_out;
1452 	*init_res = err;
1453 
1454 	if (!police && tb[TCA_ACT_COOKIE])
1455 		tcf_set_action_cookie(&a->user_cookie, user_cookie);
1456 
1457 	if (!police)
1458 		a->hw_stats = hw_stats;
1459 
1460 	return a;
1461 
1462 err_out:
1463 	if (user_cookie) {
1464 		kfree(user_cookie->data);
1465 		kfree(user_cookie);
1466 	}
1467 	return ERR_PTR(err);
1468 }
1469 
1470 static bool tc_act_bind(u32 flags)
1471 {
1472 	return !!(flags & TCA_ACT_FLAGS_BIND);
1473 }
1474 
1475 /* Returns numbers of initialized actions or negative error. */
1476 
1477 int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla,
1478 		    struct nlattr *est, struct tc_action *actions[],
1479 		    int init_res[], size_t *attr_size,
1480 		    u32 flags, u32 fl_flags,
1481 		    struct netlink_ext_ack *extack)
1482 {
1483 	struct tc_action_ops *ops[TCA_ACT_MAX_PRIO] = {};
1484 	struct nlattr *tb[TCA_ACT_MAX_PRIO + 2];
1485 	struct tc_action *act;
1486 	size_t sz = 0;
1487 	int err;
1488 	int i;
1489 
1490 	err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX_PRIO + 1, nla, NULL,
1491 					  extack);
1492 	if (err < 0)
1493 		return err;
1494 
1495 	/* The nested attributes are parsed as types, but they are really an
1496 	 * array of actions. So we parse one more than we can handle, and return
1497 	 * an error if the last one is set (as that indicates that the request
1498 	 * contained more than the maximum number of actions).
1499 	 */
1500 	if (tb[TCA_ACT_MAX_PRIO + 1]) {
1501 		NL_SET_ERR_MSG_FMT(extack,
1502 				   "Only %d actions supported per filter",
1503 				   TCA_ACT_MAX_PRIO);
1504 		return -EINVAL;
1505 	}
1506 
1507 	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1508 		struct tc_action_ops *a_o;
1509 
1510 		a_o = tc_action_load_ops(tb[i], flags, extack);
1511 		if (IS_ERR(a_o)) {
1512 			err = PTR_ERR(a_o);
1513 			goto err_mod;
1514 		}
1515 		ops[i - 1] = a_o;
1516 	}
1517 
1518 	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1519 		act = tcf_action_init_1(net, tp, tb[i], est, ops[i - 1],
1520 					&init_res[i - 1], flags, extack);
1521 		if (IS_ERR(act)) {
1522 			err = PTR_ERR(act);
1523 			goto err;
1524 		}
1525 		sz += tcf_action_fill_size(act);
1526 		/* Start from index 0 */
1527 		actions[i - 1] = act;
1528 		if (tc_act_bind(flags)) {
1529 			bool skip_sw = tc_skip_sw(fl_flags);
1530 			bool skip_hw = tc_skip_hw(fl_flags);
1531 
1532 			if (tc_act_bind(act->tcfa_flags)) {
1533 				/* Action is created by classifier and is not
1534 				 * standalone. Check that the user did not set
1535 				 * any action flags different than the
1536 				 * classifier flags, and inherit the flags from
1537 				 * the classifier for the compatibility case
1538 				 * where no flags were specified at all.
1539 				 */
1540 				if ((tc_act_skip_sw(act->tcfa_flags) && !skip_sw) ||
1541 				    (tc_act_skip_hw(act->tcfa_flags) && !skip_hw)) {
1542 					NL_SET_ERR_MSG(extack,
1543 						       "Mismatch between action and filter offload flags");
1544 					err = -EINVAL;
1545 					goto err;
1546 				}
1547 				if (skip_sw)
1548 					act->tcfa_flags |= TCA_ACT_FLAGS_SKIP_SW;
1549 				if (skip_hw)
1550 					act->tcfa_flags |= TCA_ACT_FLAGS_SKIP_HW;
1551 				continue;
1552 			}
1553 
1554 			/* Action is standalone */
1555 			if (skip_sw != tc_act_skip_sw(act->tcfa_flags) ||
1556 			    skip_hw != tc_act_skip_hw(act->tcfa_flags)) {
1557 				NL_SET_ERR_MSG(extack,
1558 					       "Mismatch between action and filter offload flags");
1559 				err = -EINVAL;
1560 				goto err;
1561 			}
1562 		} else {
1563 			err = tcf_action_offload_add(act, extack);
1564 			if (tc_act_skip_sw(act->tcfa_flags) && err)
1565 				goto err;
1566 		}
1567 	}
1568 
1569 	/* We have to commit them all together, because if any error happened in
1570 	 * between, we could not handle the failure gracefully.
1571 	 */
1572 	tcf_idr_insert_many(actions, init_res);
1573 
1574 	*attr_size = tcf_action_full_attrs_size(sz);
1575 	err = i - 1;
1576 	goto err_mod;
1577 
1578 err:
1579 	tcf_action_destroy(actions, flags & TCA_ACT_FLAGS_BIND);
1580 err_mod:
1581 	for (i = 0; i < TCA_ACT_MAX_PRIO && ops[i]; i++)
1582 		module_put(ops[i]->owner);
1583 	return err;
1584 }
1585 
1586 void tcf_action_update_stats(struct tc_action *a, u64 bytes, u64 packets,
1587 			     u64 drops, bool hw)
1588 {
1589 	if (a->cpu_bstats) {
1590 		_bstats_update(this_cpu_ptr(a->cpu_bstats), bytes, packets);
1591 
1592 		this_cpu_add(a->cpu_qstats->drops, drops);
1593 
1594 		if (hw)
1595 			_bstats_update(this_cpu_ptr(a->cpu_bstats_hw),
1596 				       bytes, packets);
1597 		return;
1598 	}
1599 
1600 	_bstats_update(&a->tcfa_bstats, bytes, packets);
1601 	atomic_add(drops, &a->tcfa_drops);
1602 	if (hw)
1603 		_bstats_update(&a->tcfa_bstats_hw, bytes, packets);
1604 }
1605 EXPORT_SYMBOL(tcf_action_update_stats);
1606 
1607 int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *p,
1608 			  int compat_mode)
1609 {
1610 	struct gnet_stats_queue qstats = {0};
1611 	struct gnet_dump d;
1612 	int err = 0;
1613 
1614 	if (p == NULL)
1615 		goto errout;
1616 
1617 	/* compat_mode being true specifies a call that is supposed
1618 	 * to add additional backward compatibility statistic TLVs.
1619 	 */
1620 	if (compat_mode) {
1621 		if (p->type == TCA_OLD_COMPAT)
1622 			err = gnet_stats_start_copy_compat(skb, 0,
1623 							   TCA_STATS,
1624 							   TCA_XSTATS,
1625 							   &p->tcfa_lock, &d,
1626 							   TCA_PAD);
1627 		else
1628 			return 0;
1629 	} else
1630 		err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
1631 					    &p->tcfa_lock, &d, TCA_ACT_PAD);
1632 
1633 	if (err < 0)
1634 		goto errout;
1635 
1636 	qstats.drops = atomic_read(&p->tcfa_drops);
1637 	qstats.overlimits = atomic_read(&p->tcfa_overlimits);
1638 
1639 	if (gnet_stats_copy_basic(&d, p->cpu_bstats,
1640 				  &p->tcfa_bstats, false) < 0 ||
1641 	    gnet_stats_copy_basic_hw(&d, p->cpu_bstats_hw,
1642 				     &p->tcfa_bstats_hw, false) < 0 ||
1643 	    gnet_stats_copy_rate_est(&d, &p->tcfa_rate_est) < 0 ||
1644 	    gnet_stats_copy_queue(&d, p->cpu_qstats,
1645 				  &qstats,
1646 				  qstats.qlen) < 0)
1647 		goto errout;
1648 
1649 	if (gnet_stats_finish_copy(&d) < 0)
1650 		goto errout;
1651 
1652 	return 0;
1653 
1654 errout:
1655 	return -1;
1656 }
1657 
1658 static int tca_get_fill(struct sk_buff *skb, struct tc_action *actions[],
1659 			u32 portid, u32 seq, u16 flags, int event, int bind,
1660 			int ref, struct netlink_ext_ack *extack)
1661 {
1662 	struct tcamsg *t;
1663 	struct nlmsghdr *nlh;
1664 	unsigned char *b = skb_tail_pointer(skb);
1665 	struct nlattr *nest;
1666 
1667 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*t), flags);
1668 	if (!nlh)
1669 		goto out_nlmsg_trim;
1670 	t = nlmsg_data(nlh);
1671 	t->tca_family = AF_UNSPEC;
1672 	t->tca__pad1 = 0;
1673 	t->tca__pad2 = 0;
1674 
1675 	if (extack && extack->_msg &&
1676 	    nla_put_string(skb, TCA_ROOT_EXT_WARN_MSG, extack->_msg))
1677 		goto out_nlmsg_trim;
1678 
1679 	nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
1680 	if (!nest)
1681 		goto out_nlmsg_trim;
1682 
1683 	if (tcf_action_dump(skb, actions, bind, ref, false) < 0)
1684 		goto out_nlmsg_trim;
1685 
1686 	nla_nest_end(skb, nest);
1687 
1688 	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1689 
1690 	return skb->len;
1691 
1692 out_nlmsg_trim:
1693 	nlmsg_trim(skb, b);
1694 	return -1;
1695 }
1696 
1697 static int
1698 tcf_get_notify(struct net *net, u32 portid, struct nlmsghdr *n,
1699 	       struct tc_action *actions[], size_t attr_size, int event,
1700 	       struct netlink_ext_ack *extack)
1701 {
1702 	struct sk_buff *skb;
1703 
1704 	skb = alloc_skb(max(attr_size, NLMSG_GOODSIZE), GFP_KERNEL);
1705 	if (!skb)
1706 		return -ENOBUFS;
1707 	if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, event,
1708 			 0, 1, NULL) <= 0) {
1709 		NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1710 		kfree_skb(skb);
1711 		return -EINVAL;
1712 	}
1713 
1714 	return rtnl_unicast(skb, net, portid);
1715 }
1716 
1717 static struct tc_action *tcf_action_get_1(struct net *net, struct nlattr *nla,
1718 					  struct nlmsghdr *n, u32 portid,
1719 					  struct netlink_ext_ack *extack)
1720 {
1721 	struct nlattr *tb[TCA_ACT_MAX + 1];
1722 	const struct tc_action_ops *ops;
1723 	struct tc_action *a;
1724 	int index;
1725 	int err;
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 	if (tb[TCA_ACT_INDEX] == NULL ||
1734 	    nla_len(tb[TCA_ACT_INDEX]) < sizeof(index)) {
1735 		NL_SET_ERR_MSG(extack, "Invalid TC action index value");
1736 		goto err_out;
1737 	}
1738 	index = nla_get_u32(tb[TCA_ACT_INDEX]);
1739 
1740 	err = -EINVAL;
1741 	ops = tc_lookup_action(tb[TCA_ACT_KIND]);
1742 	if (!ops) { /* could happen in batch of actions */
1743 		NL_SET_ERR_MSG(extack, "Specified TC action kind not found");
1744 		goto err_out;
1745 	}
1746 	err = -ENOENT;
1747 	if (__tcf_idr_search(net, ops, &a, index) == 0) {
1748 		NL_SET_ERR_MSG(extack, "TC action with specified index not found");
1749 		goto err_mod;
1750 	}
1751 
1752 	module_put(ops->owner);
1753 	return a;
1754 
1755 err_mod:
1756 	module_put(ops->owner);
1757 err_out:
1758 	return ERR_PTR(err);
1759 }
1760 
1761 static int tca_action_flush(struct net *net, struct nlattr *nla,
1762 			    struct nlmsghdr *n, u32 portid,
1763 			    struct netlink_ext_ack *extack)
1764 {
1765 	struct sk_buff *skb;
1766 	unsigned char *b;
1767 	struct nlmsghdr *nlh;
1768 	struct tcamsg *t;
1769 	struct netlink_callback dcb;
1770 	struct nlattr *nest;
1771 	struct nlattr *tb[TCA_ACT_MAX + 1];
1772 	const struct tc_action_ops *ops;
1773 	struct nlattr *kind;
1774 	int err = -ENOMEM;
1775 
1776 	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1777 	if (!skb)
1778 		return err;
1779 
1780 	b = skb_tail_pointer(skb);
1781 
1782 	err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1783 					  tcf_action_policy, extack);
1784 	if (err < 0)
1785 		goto err_out;
1786 
1787 	err = -EINVAL;
1788 	kind = tb[TCA_ACT_KIND];
1789 	ops = tc_lookup_action(kind);
1790 	if (!ops) { /*some idjot trying to flush unknown action */
1791 		NL_SET_ERR_MSG(extack, "Cannot flush unknown TC action");
1792 		goto err_out;
1793 	}
1794 
1795 	nlh = nlmsg_put(skb, portid, n->nlmsg_seq, RTM_DELACTION,
1796 			sizeof(*t), 0);
1797 	if (!nlh) {
1798 		NL_SET_ERR_MSG(extack, "Failed to create TC action flush notification");
1799 		goto out_module_put;
1800 	}
1801 	t = nlmsg_data(nlh);
1802 	t->tca_family = AF_UNSPEC;
1803 	t->tca__pad1 = 0;
1804 	t->tca__pad2 = 0;
1805 
1806 	nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
1807 	if (!nest) {
1808 		NL_SET_ERR_MSG(extack, "Failed to add new netlink message");
1809 		goto out_module_put;
1810 	}
1811 
1812 	err = __tcf_generic_walker(net, skb, &dcb, RTM_DELACTION, ops, extack);
1813 	if (err <= 0) {
1814 		nla_nest_cancel(skb, nest);
1815 		goto out_module_put;
1816 	}
1817 
1818 	nla_nest_end(skb, nest);
1819 
1820 	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1821 	nlh->nlmsg_flags |= NLM_F_ROOT;
1822 	module_put(ops->owner);
1823 	err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1824 			     n->nlmsg_flags & NLM_F_ECHO);
1825 	if (err < 0)
1826 		NL_SET_ERR_MSG(extack, "Failed to send TC action flush notification");
1827 
1828 	return err;
1829 
1830 out_module_put:
1831 	module_put(ops->owner);
1832 err_out:
1833 	kfree_skb(skb);
1834 	return err;
1835 }
1836 
1837 static int tcf_action_delete(struct net *net, struct tc_action *actions[])
1838 {
1839 	struct tc_action *a;
1840 	int i;
1841 
1842 	tcf_act_for_each_action(i, a, actions) {
1843 		const struct tc_action_ops *ops = a->ops;
1844 		/* Actions can be deleted concurrently so we must save their
1845 		 * type and id to search again after reference is released.
1846 		 */
1847 		struct tcf_idrinfo *idrinfo = a->idrinfo;
1848 		u32 act_index = a->tcfa_index;
1849 
1850 		actions[i] = NULL;
1851 		if (tcf_action_put(a)) {
1852 			/* last reference, action was deleted concurrently */
1853 			module_put(ops->owner);
1854 		} else {
1855 			int ret;
1856 
1857 			/* now do the delete */
1858 			ret = tcf_idr_delete_index(idrinfo, act_index);
1859 			if (ret < 0)
1860 				return ret;
1861 		}
1862 	}
1863 	return 0;
1864 }
1865 
1866 static struct sk_buff *tcf_reoffload_del_notify_msg(struct net *net,
1867 						    struct tc_action *action)
1868 {
1869 	struct tc_action *actions[TCA_ACT_MAX_PRIO] = {
1870 		[0] = action,
1871 	};
1872 	struct sk_buff *skb;
1873 	size_t attr_size;
1874 
1875 	attr_size = tcf_action_full_attrs_size(tcf_action_fill_size(action));
1876 
1877 	skb = alloc_skb(max(attr_size, NLMSG_GOODSIZE), GFP_KERNEL);
1878 	if (!skb)
1879 		return ERR_PTR(-ENOBUFS);
1880 
1881 	if (tca_get_fill(skb, actions, 0, 0, 0, RTM_DELACTION, 0, 1, NULL) <= 0) {
1882 		kfree_skb(skb);
1883 		return ERR_PTR(-EINVAL);
1884 	}
1885 
1886 	return skb;
1887 }
1888 
1889 static int tcf_reoffload_del_notify(struct net *net, struct tc_action *action)
1890 {
1891 	const struct tc_action_ops *ops = action->ops;
1892 	struct sk_buff *skb = NULL;
1893 	int ret;
1894 
1895 	if (rtnl_notify_needed(net, 0, RTNLGRP_TC)) {
1896 		skb = tcf_reoffload_del_notify_msg(net, action);
1897 		/* The action has already lost its hardware instance and is
1898 		 * skip_sw, so it must be released whether or not the
1899 		 * notification can be built.  Drop the notification rather
1900 		 * than leave an action behind that processes no packets.
1901 		 */
1902 		if (IS_ERR(skb))
1903 			skb = NULL;
1904 	}
1905 
1906 	ret = tcf_idr_release_unsafe(action);
1907 	if (ret == ACT_P_DELETED) {
1908 		module_put(ops->owner);
1909 		ret = rtnetlink_maybe_send(skb, net, 0, RTNLGRP_TC, 0);
1910 	} else {
1911 		kfree_skb(skb);
1912 	}
1913 
1914 	return ret;
1915 }
1916 
1917 int tcf_action_reoffload_cb(flow_indr_block_bind_cb_t *cb,
1918 			    void *cb_priv, bool add)
1919 {
1920 	struct tc_act_pernet_id *id_ptr;
1921 	struct tcf_idrinfo *idrinfo;
1922 	struct tc_action_net *tn;
1923 	struct tc_action *p;
1924 	unsigned int act_id;
1925 	unsigned long tmp;
1926 	unsigned long id;
1927 	struct idr *idr;
1928 	struct net *net;
1929 	int ret;
1930 
1931 	if (!cb)
1932 		return -EINVAL;
1933 
1934 	down_read(&net_rwsem);
1935 	mutex_lock(&act_id_mutex);
1936 
1937 	for_each_net(net) {
1938 		list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
1939 			act_id = id_ptr->id;
1940 			tn = net_generic(net, act_id);
1941 			if (!tn)
1942 				continue;
1943 			idrinfo = tn->idrinfo;
1944 			if (!idrinfo)
1945 				continue;
1946 
1947 			mutex_lock(&idrinfo->lock);
1948 			idr = &idrinfo->action_idr;
1949 			idr_for_each_entry_ul(idr, p, tmp, id) {
1950 				if (IS_ERR(p) || tc_act_bind(p->tcfa_flags))
1951 					continue;
1952 				if (add) {
1953 					tcf_action_offload_add_ex(p, NULL, cb,
1954 								  cb_priv);
1955 					continue;
1956 				}
1957 
1958 				/* cb unregister to update hw count */
1959 				ret = tcf_action_offload_del_ex(p, cb, cb_priv);
1960 				if (ret < 0)
1961 					continue;
1962 				if (tc_act_skip_sw(p->tcfa_flags) &&
1963 				    !tc_act_in_hw(p))
1964 					tcf_reoffload_del_notify(net, p);
1965 			}
1966 			mutex_unlock(&idrinfo->lock);
1967 		}
1968 	}
1969 	mutex_unlock(&act_id_mutex);
1970 	up_read(&net_rwsem);
1971 
1972 	return 0;
1973 }
1974 
1975 static struct sk_buff *tcf_del_notify_msg(struct net *net, struct nlmsghdr *n,
1976 					  struct tc_action *actions[],
1977 					  u32 portid, size_t attr_size,
1978 					  struct netlink_ext_ack *extack)
1979 {
1980 	struct sk_buff *skb;
1981 
1982 	skb = alloc_skb(max(attr_size, NLMSG_GOODSIZE), GFP_KERNEL);
1983 	if (!skb)
1984 		return ERR_PTR(-ENOBUFS);
1985 
1986 	if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, RTM_DELACTION,
1987 			 0, 2, extack) <= 0) {
1988 		NL_SET_ERR_MSG(extack, "Failed to fill netlink TC action attributes");
1989 		kfree_skb(skb);
1990 		return ERR_PTR(-EINVAL);
1991 	}
1992 
1993 	return skb;
1994 }
1995 
1996 static int tcf_del_notify(struct net *net, struct nlmsghdr *n,
1997 			  struct tc_action *actions[], u32 portid,
1998 			  size_t attr_size, struct netlink_ext_ack *extack)
1999 {
2000 	struct sk_buff *skb;
2001 	int ret;
2002 
2003 	if (!rtnl_notify_needed(net, n->nlmsg_flags, RTNLGRP_TC)) {
2004 		skb = NULL;
2005 	} else {
2006 		skb = tcf_del_notify_msg(net, n, actions, portid, attr_size,
2007 					 extack);
2008 		if (IS_ERR(skb))
2009 			return PTR_ERR(skb);
2010 	}
2011 
2012 	/* now do the delete */
2013 	ret = tcf_action_delete(net, actions);
2014 	if (ret < 0) {
2015 		NL_SET_ERR_MSG(extack, "Failed to delete TC action");
2016 		kfree_skb(skb);
2017 		return ret;
2018 	}
2019 
2020 	return rtnetlink_maybe_send(skb, net, portid, RTNLGRP_TC,
2021 				    n->nlmsg_flags & NLM_F_ECHO);
2022 }
2023 
2024 static int
2025 tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
2026 	      u32 portid, int event, struct netlink_ext_ack *extack)
2027 {
2028 	int i, ret;
2029 	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
2030 	struct tc_action *act;
2031 	size_t attr_size = 0;
2032 	struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
2033 
2034 	ret = nla_parse_nested_deprecated(tb, TCA_ACT_MAX_PRIO, nla, NULL,
2035 					  extack);
2036 	if (ret < 0)
2037 		return ret;
2038 
2039 	if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) {
2040 		if (tb[1])
2041 			return tca_action_flush(net, tb[1], n, portid, extack);
2042 
2043 		NL_SET_ERR_MSG(extack, "Invalid netlink attributes while flushing TC action");
2044 		return -EINVAL;
2045 	}
2046 
2047 	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
2048 		act = tcf_action_get_1(net, tb[i], n, portid, extack);
2049 		if (IS_ERR(act)) {
2050 			ret = PTR_ERR(act);
2051 			goto err;
2052 		}
2053 		attr_size += tcf_action_fill_size(act);
2054 		actions[i - 1] = act;
2055 	}
2056 
2057 	attr_size = tcf_action_full_attrs_size(attr_size);
2058 
2059 	if (event == RTM_GETACTION)
2060 		ret = tcf_get_notify(net, portid, n, actions, attr_size, event,
2061 				     extack);
2062 	else { /* delete */
2063 		ret = tcf_del_notify(net, n, actions, portid, attr_size, extack);
2064 		if (ret)
2065 			goto err;
2066 		return 0;
2067 	}
2068 err:
2069 	tcf_action_put_many(actions);
2070 	return ret;
2071 }
2072 
2073 static struct sk_buff *tcf_add_notify_msg(struct net *net, struct nlmsghdr *n,
2074 					  struct tc_action *actions[],
2075 					  u32 portid, size_t attr_size,
2076 					  struct netlink_ext_ack *extack)
2077 {
2078 	struct sk_buff *skb;
2079 
2080 	skb = alloc_skb(max(attr_size, NLMSG_GOODSIZE), GFP_KERNEL);
2081 	if (!skb)
2082 		return ERR_PTR(-ENOBUFS);
2083 
2084 	if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, n->nlmsg_flags,
2085 			 RTM_NEWACTION, 0, 0, extack) <= 0) {
2086 		NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
2087 		kfree_skb(skb);
2088 		return ERR_PTR(-EINVAL);
2089 	}
2090 
2091 	return skb;
2092 }
2093 
2094 static int tcf_add_notify(struct net *net, struct nlmsghdr *n,
2095 			  struct tc_action *actions[], u32 portid,
2096 			  size_t attr_size, struct netlink_ext_ack *extack)
2097 {
2098 	struct sk_buff *skb;
2099 
2100 	if (!rtnl_notify_needed(net, n->nlmsg_flags, RTNLGRP_TC)) {
2101 		skb = NULL;
2102 	} else {
2103 		skb = tcf_add_notify_msg(net, n, actions, portid, attr_size,
2104 					 extack);
2105 		if (IS_ERR(skb))
2106 			return PTR_ERR(skb);
2107 	}
2108 
2109 	return rtnetlink_maybe_send(skb, net, portid, RTNLGRP_TC,
2110 				    n->nlmsg_flags & NLM_F_ECHO);
2111 }
2112 
2113 static int tcf_action_add(struct net *net, struct nlattr *nla,
2114 			  struct nlmsghdr *n, u32 portid, u32 flags,
2115 			  struct netlink_ext_ack *extack)
2116 {
2117 	size_t attr_size = 0;
2118 	int loop, ret;
2119 	struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
2120 	int init_res[TCA_ACT_MAX_PRIO] = {};
2121 
2122 	for (loop = 0; loop < 10; loop++) {
2123 		ret = tcf_action_init(net, NULL, nla, NULL, actions, init_res,
2124 				      &attr_size, flags, 0, extack);
2125 		if (ret != -EAGAIN)
2126 			break;
2127 	}
2128 
2129 	if (ret < 0)
2130 		return ret;
2131 
2132 	ret = tcf_add_notify(net, n, actions, portid, attr_size, extack);
2133 
2134 	/* only put bound actions */
2135 	tca_put_bound_many(actions, init_res);
2136 
2137 	return ret;
2138 }
2139 
2140 static const struct nla_policy tcaa_policy[TCA_ROOT_MAX + 1] = {
2141 	[TCA_ROOT_FLAGS] = NLA_POLICY_BITFIELD32(TCA_ACT_FLAG_LARGE_DUMP_ON |
2142 						 TCA_ACT_FLAG_TERSE_DUMP),
2143 	[TCA_ROOT_TIME_DELTA]      = { .type = NLA_U32 },
2144 };
2145 
2146 static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n,
2147 			 struct netlink_ext_ack *extack)
2148 {
2149 	struct net *net = sock_net(skb->sk);
2150 	struct nlattr *tca[TCA_ROOT_MAX + 1];
2151 	u32 portid = NETLINK_CB(skb).portid;
2152 	u32 flags = 0;
2153 	int ret = 0;
2154 
2155 	if ((n->nlmsg_type != RTM_GETACTION) &&
2156 	    !netlink_capable(skb, CAP_NET_ADMIN))
2157 		return -EPERM;
2158 
2159 	ret = nlmsg_parse_deprecated(n, sizeof(struct tcamsg), tca,
2160 				     TCA_ROOT_MAX, NULL, extack);
2161 	if (ret < 0)
2162 		return ret;
2163 
2164 	if (tca[TCA_ACT_TAB] == NULL) {
2165 		NL_SET_ERR_MSG(extack, "Netlink action attributes missing");
2166 		return -EINVAL;
2167 	}
2168 
2169 	/* n->nlmsg_flags & NLM_F_CREATE */
2170 	switch (n->nlmsg_type) {
2171 	case RTM_NEWACTION:
2172 		/* we are going to assume all other flags
2173 		 * imply create only if it doesn't exist
2174 		 * Note that CREATE | EXCL implies that
2175 		 * but since we want avoid ambiguity (eg when flags
2176 		 * is zero) then just set this
2177 		 */
2178 		if (n->nlmsg_flags & NLM_F_REPLACE)
2179 			flags = TCA_ACT_FLAGS_REPLACE;
2180 		ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, portid, flags,
2181 				     extack);
2182 		break;
2183 	case RTM_DELACTION:
2184 		ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
2185 				    portid, RTM_DELACTION, extack);
2186 		break;
2187 	case RTM_GETACTION:
2188 		ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
2189 				    portid, RTM_GETACTION, extack);
2190 		break;
2191 	default:
2192 		BUG();
2193 	}
2194 
2195 	return ret;
2196 }
2197 
2198 static struct nlattr *find_dump_kind(struct nlattr **nla)
2199 {
2200 	struct nlattr *tb1, *tb2[TCA_ACT_MAX + 1];
2201 	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
2202 	struct nlattr *kind;
2203 
2204 	tb1 = nla[TCA_ACT_TAB];
2205 	if (tb1 == NULL)
2206 		return NULL;
2207 
2208 	if (nla_parse_deprecated(tb, TCA_ACT_MAX_PRIO, nla_data(tb1), NLMSG_ALIGN(nla_len(tb1)), NULL, NULL) < 0)
2209 		return NULL;
2210 
2211 	if (tb[1] == NULL)
2212 		return NULL;
2213 	if (nla_parse_nested_deprecated(tb2, TCA_ACT_MAX, tb[1], tcf_action_policy, NULL) < 0)
2214 		return NULL;
2215 	kind = tb2[TCA_ACT_KIND];
2216 
2217 	return kind;
2218 }
2219 
2220 static int tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
2221 {
2222 	struct net *net = sock_net(skb->sk);
2223 	struct nlmsghdr *nlh;
2224 	unsigned char *b = skb_tail_pointer(skb);
2225 	struct nlattr *nest;
2226 	struct tc_action_ops *a_o;
2227 	int ret = 0;
2228 	struct tcamsg *t = (struct tcamsg *) nlmsg_data(cb->nlh);
2229 	struct nlattr *tb[TCA_ROOT_MAX + 1];
2230 	struct nlattr *count_attr = NULL;
2231 	unsigned long jiffy_since = 0;
2232 	struct nlattr *kind = NULL;
2233 	struct nla_bitfield32 bf;
2234 	u32 msecs_since = 0;
2235 	u32 act_count = 0;
2236 
2237 	ret = nlmsg_parse_deprecated(cb->nlh, sizeof(struct tcamsg), tb,
2238 				     TCA_ROOT_MAX, tcaa_policy, cb->extack);
2239 	if (ret < 0)
2240 		return ret;
2241 
2242 	kind = find_dump_kind(tb);
2243 	if (kind == NULL) {
2244 		pr_info("tc_dump_action: action bad kind\n");
2245 		return 0;
2246 	}
2247 
2248 	a_o = tc_lookup_action(kind);
2249 	if (a_o == NULL)
2250 		return 0;
2251 
2252 	cb->args[2] = 0;
2253 	if (tb[TCA_ROOT_FLAGS]) {
2254 		bf = nla_get_bitfield32(tb[TCA_ROOT_FLAGS]);
2255 		cb->args[2] = bf.value;
2256 	}
2257 
2258 	if (tb[TCA_ROOT_TIME_DELTA]) {
2259 		msecs_since = nla_get_u32(tb[TCA_ROOT_TIME_DELTA]);
2260 	}
2261 
2262 	nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
2263 			cb->nlh->nlmsg_type, sizeof(*t), 0);
2264 	if (!nlh)
2265 		goto out_module_put;
2266 
2267 	if (msecs_since)
2268 		jiffy_since = jiffies - msecs_to_jiffies(msecs_since);
2269 
2270 	t = nlmsg_data(nlh);
2271 	t->tca_family = AF_UNSPEC;
2272 	t->tca__pad1 = 0;
2273 	t->tca__pad2 = 0;
2274 	cb->args[3] = jiffy_since;
2275 	count_attr = nla_reserve(skb, TCA_ROOT_COUNT, sizeof(u32));
2276 	if (!count_attr)
2277 		goto out_module_put;
2278 
2279 	nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
2280 	if (nest == NULL)
2281 		goto out_module_put;
2282 
2283 	ret = __tcf_generic_walker(net, skb, cb, RTM_GETACTION, a_o, NULL);
2284 	if (ret < 0)
2285 		goto out_module_put;
2286 
2287 	if (ret > 0) {
2288 		nla_nest_end(skb, nest);
2289 		ret = skb->len;
2290 		act_count = cb->args[1];
2291 		memcpy(nla_data(count_attr), &act_count, sizeof(u32));
2292 		cb->args[1] = 0;
2293 	} else
2294 		nlmsg_trim(skb, b);
2295 
2296 	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
2297 	if (NETLINK_CB(cb->skb).portid && ret)
2298 		nlh->nlmsg_flags |= NLM_F_MULTI;
2299 	module_put(a_o->owner);
2300 	return skb->len;
2301 
2302 out_module_put:
2303 	module_put(a_o->owner);
2304 	nlmsg_trim(skb, b);
2305 	return skb->len;
2306 }
2307 
2308 static const struct rtnl_msg_handler tc_action_rtnl_msg_handlers[] __initconst = {
2309 	{.msgtype = RTM_NEWACTION, .doit = tc_ctl_action},
2310 	{.msgtype = RTM_DELACTION, .doit = tc_ctl_action},
2311 	{.msgtype = RTM_GETACTION, .doit = tc_ctl_action,
2312 	 .dumpit = tc_dump_action},
2313 };
2314 
2315 static int __init tc_action_init(void)
2316 {
2317 	rtnl_register_many(tc_action_rtnl_msg_handlers);
2318 	return 0;
2319 }
2320 
2321 subsys_initcall(tc_action_init);
2322