xref: /linux/net/sched/act_api.c (revision a1ff5a7d78a036d6c2178ee5acd6ba4946243800)
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 
tcf_dev_queue_xmit(struct sk_buff * skb,int (* xmit)(struct sk_buff * skb))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 
tcf_action_goto_chain_exec(const struct tc_action * a,struct tcf_result * res)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 
tcf_free_cookie_rcu(struct rcu_head * p)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 
tcf_set_action_cookie(struct tc_cookie __rcu ** old_cookie,struct tc_cookie * new_cookie)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 = unrcu_pointer(xchg(old_cookie, RCU_INITIALIZER(new_cookie)));
66 	if (old)
67 		call_rcu(&old->rcu, tcf_free_cookie_rcu);
68 }
69 
tcf_action_check_ctrlact(int action,struct tcf_proto * tp,struct tcf_chain ** newchain,struct netlink_ext_ack * extack)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 
tcf_action_set_ctrlact(struct tc_action * a,int action,struct tcf_chain * goto_chain)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  */
free_tcf(struct tc_action * p)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 
offload_action_hw_count_set(struct tc_action * act,u32 hw_count)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 
offload_action_hw_count_inc(struct tc_action * act,u32 hw_count)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 
offload_action_hw_count_dec(struct tc_action * act,u32 hw_count)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 
tcf_offload_act_num_actions_single(struct tc_action * act)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 
tc_act_skip_hw(u32 flags)162 static bool tc_act_skip_hw(u32 flags)
163 {
164 	return (flags & TCA_ACT_FLAGS_SKIP_HW) ? true : false;
165 }
166 
tc_act_skip_sw(u32 flags)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. */
tc_act_flags_valid(u32 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 
offload_action_init(struct flow_offload_action * fl_action,struct tc_action * act,enum offload_act_command cmd,struct netlink_ext_ack * extack)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 
tcf_action_offload_cmd_ex(struct flow_offload_action * fl_act,u32 * hw_count)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 
tcf_action_offload_cmd_cb_ex(struct flow_offload_action * fl_act,u32 * hw_count,flow_indr_block_bind_cb_t * cb,void * cb_priv)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 
tcf_action_offload_cmd(struct flow_offload_action * fl_act,u32 * hw_count,flow_indr_block_bind_cb_t * cb,void * cb_priv)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 
tcf_action_offload_add_ex(struct tc_action * action,struct netlink_ext_ack * extack,flow_indr_block_bind_cb_t * cb,void * cb_priv)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 */
tcf_action_offload_add(struct tc_action * action,struct netlink_ext_ack * extack)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 
tcf_action_update_hw_stats(struct tc_action * action)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 
tcf_action_offload_del_ex(struct tc_action * action,flow_indr_block_bind_cb_t * cb,void * cb_priv)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 
tcf_action_offload_del(struct tc_action * action)358 static int tcf_action_offload_del(struct tc_action *action)
359 {
360 	return tcf_action_offload_del_ex(action, NULL, NULL);
361 }
362 
tcf_action_cleanup(struct tc_action * p)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 
__tcf_action_put(struct tc_action * p,bool bind)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 
__tcf_idr_release(struct tc_action * p,bool bind,bool strict)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 
tcf_idr_release(struct tc_action * a,bool bind)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 
tcf_action_shared_attrs_size(const struct tc_action * act)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 
tcf_action_full_attrs_size(size_t sz)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 
tcf_action_fill_size(const struct tc_action * act)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
tcf_action_dump_terse(struct sk_buff * skb,struct tc_action * a,bool from_act)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 
tcf_dump_walker(struct tcf_idrinfo * idrinfo,struct sk_buff * skb,struct netlink_callback * cb)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 
tcf_idr_release_unsafe(struct tc_action * p)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 
tcf_del_walker(struct tcf_idrinfo * idrinfo,struct sk_buff * skb,const struct tc_action_ops * ops,struct netlink_ext_ack * extack)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 
tcf_generic_walker(struct tc_action_net * tn,struct sk_buff * skb,struct netlink_callback * cb,int type,const struct tc_action_ops * ops,struct netlink_ext_ack * extack)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 
tcf_idr_search(struct tc_action_net * tn,struct tc_action ** a,u32 index)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 
__tcf_generic_walker(struct net * net,struct sk_buff * skb,struct netlink_callback * cb,int type,const struct tc_action_ops * ops,struct netlink_ext_ack * extack)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 
__tcf_idr_search(struct net * net,const struct tc_action_ops * ops,struct tc_action ** a,u32 index)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 
tcf_idr_delete_index(struct tcf_idrinfo * idrinfo,u32 index)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 
tcf_idr_create(struct tc_action_net * tn,u32 index,struct nlattr * est,struct tc_action ** a,const struct tc_action_ops * ops,int bind,bool cpustats,u32 flags)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 
tcf_idr_create_from_flags(struct tc_action_net * tn,u32 index,struct nlattr * est,struct tc_action ** a,const struct tc_action_ops * ops,int bind,u32 flags)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 
tcf_idr_cleanup(struct tc_action_net * tn,u32 index)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 
tcf_idr_check_alloc(struct tc_action_net * tn,u32 * index,struct tc_action ** a,int bind)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 		rcu_read_lock();
834 		p = idr_find(&idrinfo->action_idr, *index);
835 
836 		if (IS_ERR(p)) {
837 			/* This means that another process allocated
838 			 * index but did not assign the pointer yet.
839 			 */
840 			rcu_read_unlock();
841 			return -EAGAIN;
842 		}
843 
844 		if (!p) {
845 			/* Empty slot, try to allocate it */
846 			max = *index;
847 			rcu_read_unlock();
848 			goto new;
849 		}
850 
851 		if (!refcount_inc_not_zero(&p->tcfa_refcnt)) {
852 			/* Action was deleted in parallel */
853 			rcu_read_unlock();
854 			return -EAGAIN;
855 		}
856 
857 		if (bind)
858 			atomic_inc(&p->tcfa_bindcnt);
859 		*a = p;
860 
861 		rcu_read_unlock();
862 
863 		return 1;
864 	} else {
865 		/* Find a slot */
866 		*index = 1;
867 		max = UINT_MAX;
868 	}
869 
870 new:
871 	*a = NULL;
872 
873 	mutex_lock(&idrinfo->lock);
874 	ret = idr_alloc_u32(&idrinfo->action_idr, ERR_PTR(-EBUSY), index, max,
875 			    GFP_KERNEL);
876 	mutex_unlock(&idrinfo->lock);
877 
878 	/* N binds raced for action allocation,
879 	 * retry for all the ones that failed.
880 	 */
881 	if (ret == -ENOSPC && *index == max)
882 		ret = -EAGAIN;
883 
884 	return ret;
885 }
886 EXPORT_SYMBOL(tcf_idr_check_alloc);
887 
tcf_idrinfo_destroy(const struct tc_action_ops * ops,struct tcf_idrinfo * idrinfo)888 void tcf_idrinfo_destroy(const struct tc_action_ops *ops,
889 			 struct tcf_idrinfo *idrinfo)
890 {
891 	struct idr *idr = &idrinfo->action_idr;
892 	struct tc_action *p;
893 	int ret;
894 	unsigned long id = 1;
895 	unsigned long tmp;
896 
897 	idr_for_each_entry_ul(idr, p, tmp, id) {
898 		ret = __tcf_idr_release(p, false, true);
899 		if (ret == ACT_P_DELETED)
900 			module_put(ops->owner);
901 		else if (ret < 0)
902 			return;
903 	}
904 	idr_destroy(&idrinfo->action_idr);
905 }
906 EXPORT_SYMBOL(tcf_idrinfo_destroy);
907 
908 static LIST_HEAD(act_base);
909 static DEFINE_RWLOCK(act_mod_lock);
910 /* since act ops id is stored in pernet subsystem list,
911  * then there is no way to walk through only all the action
912  * subsystem, so we keep tc action pernet ops id for
913  * reoffload to walk through.
914  */
915 static LIST_HEAD(act_pernet_id_list);
916 static DEFINE_MUTEX(act_id_mutex);
917 struct tc_act_pernet_id {
918 	struct list_head list;
919 	unsigned int id;
920 };
921 
tcf_pernet_add_id_list(unsigned int id)922 static int tcf_pernet_add_id_list(unsigned int id)
923 {
924 	struct tc_act_pernet_id *id_ptr;
925 	int ret = 0;
926 
927 	mutex_lock(&act_id_mutex);
928 	list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
929 		if (id_ptr->id == id) {
930 			ret = -EEXIST;
931 			goto err_out;
932 		}
933 	}
934 
935 	id_ptr = kzalloc(sizeof(*id_ptr), GFP_KERNEL);
936 	if (!id_ptr) {
937 		ret = -ENOMEM;
938 		goto err_out;
939 	}
940 	id_ptr->id = id;
941 
942 	list_add_tail(&id_ptr->list, &act_pernet_id_list);
943 
944 err_out:
945 	mutex_unlock(&act_id_mutex);
946 	return ret;
947 }
948 
tcf_pernet_del_id_list(unsigned int id)949 static void tcf_pernet_del_id_list(unsigned int id)
950 {
951 	struct tc_act_pernet_id *id_ptr;
952 
953 	mutex_lock(&act_id_mutex);
954 	list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
955 		if (id_ptr->id == id) {
956 			list_del(&id_ptr->list);
957 			kfree(id_ptr);
958 			break;
959 		}
960 	}
961 	mutex_unlock(&act_id_mutex);
962 }
963 
tcf_register_action(struct tc_action_ops * act,struct pernet_operations * ops)964 int tcf_register_action(struct tc_action_ops *act,
965 			struct pernet_operations *ops)
966 {
967 	struct tc_action_ops *a;
968 	int ret;
969 
970 	if (!act->act || !act->dump || !act->init)
971 		return -EINVAL;
972 
973 	/* We have to register pernet ops before making the action ops visible,
974 	 * otherwise tcf_action_init_1() could get a partially initialized
975 	 * netns.
976 	 */
977 	ret = register_pernet_subsys(ops);
978 	if (ret)
979 		return ret;
980 
981 	if (ops->id) {
982 		ret = tcf_pernet_add_id_list(*ops->id);
983 		if (ret)
984 			goto err_id;
985 	}
986 
987 	write_lock(&act_mod_lock);
988 	list_for_each_entry(a, &act_base, head) {
989 		if (act->id == a->id || (strcmp(act->kind, a->kind) == 0)) {
990 			ret = -EEXIST;
991 			goto err_out;
992 		}
993 	}
994 	list_add_tail(&act->head, &act_base);
995 	write_unlock(&act_mod_lock);
996 
997 	return 0;
998 
999 err_out:
1000 	write_unlock(&act_mod_lock);
1001 	if (ops->id)
1002 		tcf_pernet_del_id_list(*ops->id);
1003 err_id:
1004 	unregister_pernet_subsys(ops);
1005 	return ret;
1006 }
1007 EXPORT_SYMBOL(tcf_register_action);
1008 
tcf_unregister_action(struct tc_action_ops * act,struct pernet_operations * ops)1009 int tcf_unregister_action(struct tc_action_ops *act,
1010 			  struct pernet_operations *ops)
1011 {
1012 	struct tc_action_ops *a;
1013 	int err = -ENOENT;
1014 
1015 	write_lock(&act_mod_lock);
1016 	list_for_each_entry(a, &act_base, head) {
1017 		if (a == act) {
1018 			list_del(&act->head);
1019 			err = 0;
1020 			break;
1021 		}
1022 	}
1023 	write_unlock(&act_mod_lock);
1024 	if (!err) {
1025 		unregister_pernet_subsys(ops);
1026 		if (ops->id)
1027 			tcf_pernet_del_id_list(*ops->id);
1028 	}
1029 	return err;
1030 }
1031 EXPORT_SYMBOL(tcf_unregister_action);
1032 
1033 /* lookup by name */
tc_lookup_action_n(char * kind)1034 static struct tc_action_ops *tc_lookup_action_n(char *kind)
1035 {
1036 	struct tc_action_ops *a, *res = NULL;
1037 
1038 	if (kind) {
1039 		read_lock(&act_mod_lock);
1040 		list_for_each_entry(a, &act_base, head) {
1041 			if (strcmp(kind, a->kind) == 0) {
1042 				if (try_module_get(a->owner))
1043 					res = a;
1044 				break;
1045 			}
1046 		}
1047 		read_unlock(&act_mod_lock);
1048 	}
1049 	return res;
1050 }
1051 
1052 /* lookup by nlattr */
tc_lookup_action(struct nlattr * kind)1053 static struct tc_action_ops *tc_lookup_action(struct nlattr *kind)
1054 {
1055 	struct tc_action_ops *a, *res = NULL;
1056 
1057 	if (kind) {
1058 		read_lock(&act_mod_lock);
1059 		list_for_each_entry(a, &act_base, head) {
1060 			if (nla_strcmp(kind, a->kind) == 0) {
1061 				if (try_module_get(a->owner))
1062 					res = a;
1063 				break;
1064 			}
1065 		}
1066 		read_unlock(&act_mod_lock);
1067 	}
1068 	return res;
1069 }
1070 
1071 /*TCA_ACT_MAX_PRIO is 32, there count up to 32 */
1072 #define TCA_ACT_MAX_PRIO_MASK 0x1FF
tcf_action_exec(struct sk_buff * skb,struct tc_action ** actions,int nr_actions,struct tcf_result * res)1073 int tcf_action_exec(struct sk_buff *skb, struct tc_action **actions,
1074 		    int nr_actions, struct tcf_result *res)
1075 {
1076 	u32 jmp_prgcnt = 0;
1077 	u32 jmp_ttl = TCA_ACT_MAX_PRIO; /*matches actions per filter */
1078 	int i;
1079 	int ret = TC_ACT_OK;
1080 
1081 	if (skb_skip_tc_classify(skb))
1082 		return TC_ACT_OK;
1083 
1084 restart_act_graph:
1085 	for (i = 0; i < nr_actions; i++) {
1086 		const struct tc_action *a = actions[i];
1087 		int repeat_ttl;
1088 
1089 		if (jmp_prgcnt > 0) {
1090 			jmp_prgcnt -= 1;
1091 			continue;
1092 		}
1093 
1094 		if (tc_act_skip_sw(a->tcfa_flags))
1095 			continue;
1096 
1097 		repeat_ttl = 32;
1098 repeat:
1099 		ret = tc_act(skb, a, res);
1100 		if (unlikely(ret == TC_ACT_REPEAT)) {
1101 			if (--repeat_ttl != 0)
1102 				goto repeat;
1103 			/* suspicious opcode, stop pipeline */
1104 			net_warn_ratelimited("TC_ACT_REPEAT abuse ?\n");
1105 			return TC_ACT_OK;
1106 		}
1107 		if (TC_ACT_EXT_CMP(ret, TC_ACT_JUMP)) {
1108 			jmp_prgcnt = ret & TCA_ACT_MAX_PRIO_MASK;
1109 			if (!jmp_prgcnt || (jmp_prgcnt > nr_actions)) {
1110 				/* faulty opcode, stop pipeline */
1111 				return TC_ACT_OK;
1112 			} else {
1113 				jmp_ttl -= 1;
1114 				if (jmp_ttl > 0)
1115 					goto restart_act_graph;
1116 				else /* faulty graph, stop pipeline */
1117 					return TC_ACT_OK;
1118 			}
1119 		} else if (TC_ACT_EXT_CMP(ret, TC_ACT_GOTO_CHAIN)) {
1120 			if (unlikely(!rcu_access_pointer(a->goto_chain))) {
1121 				tcf_set_drop_reason(skb,
1122 						    SKB_DROP_REASON_TC_CHAIN_NOTFOUND);
1123 				return TC_ACT_SHOT;
1124 			}
1125 			tcf_action_goto_chain_exec(a, res);
1126 		}
1127 
1128 		if (ret != TC_ACT_PIPE)
1129 			break;
1130 	}
1131 
1132 	return ret;
1133 }
1134 EXPORT_SYMBOL(tcf_action_exec);
1135 
tcf_action_destroy(struct tc_action * actions[],int bind)1136 int tcf_action_destroy(struct tc_action *actions[], int bind)
1137 {
1138 	const struct tc_action_ops *ops;
1139 	struct tc_action *a;
1140 	int ret = 0, i;
1141 
1142 	tcf_act_for_each_action(i, a, actions) {
1143 		actions[i] = NULL;
1144 		ops = a->ops;
1145 		ret = __tcf_idr_release(a, bind, true);
1146 		if (ret == ACT_P_DELETED)
1147 			module_put(ops->owner);
1148 		else if (ret < 0)
1149 			return ret;
1150 	}
1151 	return ret;
1152 }
1153 
tcf_action_put(struct tc_action * p)1154 static int tcf_action_put(struct tc_action *p)
1155 {
1156 	return __tcf_action_put(p, false);
1157 }
1158 
tcf_action_put_many(struct tc_action * actions[])1159 static void tcf_action_put_many(struct tc_action *actions[])
1160 {
1161 	struct tc_action *a;
1162 	int i;
1163 
1164 	tcf_act_for_each_action(i, a, actions) {
1165 		const struct tc_action_ops *ops = a->ops;
1166 		if (tcf_action_put(a))
1167 			module_put(ops->owner);
1168 	}
1169 }
1170 
tca_put_bound_many(struct tc_action * actions[],int init_res[])1171 static void tca_put_bound_many(struct tc_action *actions[], int init_res[])
1172 {
1173 	struct tc_action *a;
1174 	int i;
1175 
1176 	tcf_act_for_each_action(i, a, actions) {
1177 		const struct tc_action_ops *ops = a->ops;
1178 
1179 		if (init_res[i] == ACT_P_CREATED)
1180 			continue;
1181 
1182 		if (tcf_action_put(a))
1183 			module_put(ops->owner);
1184 	}
1185 }
1186 
1187 int
tcf_action_dump_old(struct sk_buff * skb,struct tc_action * a,int bind,int ref)1188 tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
1189 {
1190 	return a->ops->dump(skb, a, bind, ref);
1191 }
1192 
1193 int
tcf_action_dump_1(struct sk_buff * skb,struct tc_action * a,int bind,int ref)1194 tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
1195 {
1196 	int err = -EINVAL;
1197 	unsigned char *b = skb_tail_pointer(skb);
1198 	struct nlattr *nest;
1199 	u32 flags;
1200 
1201 	if (tcf_action_dump_terse(skb, a, false))
1202 		goto nla_put_failure;
1203 
1204 	if (a->hw_stats != TCA_ACT_HW_STATS_ANY &&
1205 	    nla_put_bitfield32(skb, TCA_ACT_HW_STATS,
1206 			       a->hw_stats, TCA_ACT_HW_STATS_ANY))
1207 		goto nla_put_failure;
1208 
1209 	if (a->used_hw_stats_valid &&
1210 	    nla_put_bitfield32(skb, TCA_ACT_USED_HW_STATS,
1211 			       a->used_hw_stats, TCA_ACT_HW_STATS_ANY))
1212 		goto nla_put_failure;
1213 
1214 	flags = a->tcfa_flags & TCA_ACT_FLAGS_USER_MASK;
1215 	if (flags &&
1216 	    nla_put_bitfield32(skb, TCA_ACT_FLAGS,
1217 			       flags, flags))
1218 		goto nla_put_failure;
1219 
1220 	if (nla_put_u32(skb, TCA_ACT_IN_HW_COUNT, a->in_hw_count))
1221 		goto nla_put_failure;
1222 
1223 	nest = nla_nest_start_noflag(skb, TCA_ACT_OPTIONS);
1224 	if (nest == NULL)
1225 		goto nla_put_failure;
1226 	err = tcf_action_dump_old(skb, a, bind, ref);
1227 	if (err > 0) {
1228 		nla_nest_end(skb, nest);
1229 		return err;
1230 	}
1231 
1232 nla_put_failure:
1233 	nlmsg_trim(skb, b);
1234 	return -1;
1235 }
1236 EXPORT_SYMBOL(tcf_action_dump_1);
1237 
tcf_action_dump(struct sk_buff * skb,struct tc_action * actions[],int bind,int ref,bool terse)1238 int tcf_action_dump(struct sk_buff *skb, struct tc_action *actions[],
1239 		    int bind, int ref, bool terse)
1240 {
1241 	struct tc_action *a;
1242 	int err = -EINVAL, i;
1243 	struct nlattr *nest;
1244 
1245 	tcf_act_for_each_action(i, a, actions) {
1246 		nest = nla_nest_start_noflag(skb, i + 1);
1247 		if (nest == NULL)
1248 			goto nla_put_failure;
1249 		err = terse ? tcf_action_dump_terse(skb, a, false) :
1250 			tcf_action_dump_1(skb, a, bind, ref);
1251 		if (err < 0)
1252 			goto errout;
1253 		nla_nest_end(skb, nest);
1254 	}
1255 
1256 	return 0;
1257 
1258 nla_put_failure:
1259 	err = -EINVAL;
1260 errout:
1261 	nla_nest_cancel(skb, nest);
1262 	return err;
1263 }
1264 
nla_memdup_cookie(struct nlattr ** tb)1265 static struct tc_cookie *nla_memdup_cookie(struct nlattr **tb)
1266 {
1267 	struct tc_cookie *c = kzalloc(sizeof(*c), GFP_KERNEL);
1268 	if (!c)
1269 		return NULL;
1270 
1271 	c->data = nla_memdup(tb[TCA_ACT_COOKIE], GFP_KERNEL);
1272 	if (!c->data) {
1273 		kfree(c);
1274 		return NULL;
1275 	}
1276 	c->len = nla_len(tb[TCA_ACT_COOKIE]);
1277 
1278 	return c;
1279 }
1280 
tcf_action_hw_stats_get(struct nlattr * hw_stats_attr)1281 static u8 tcf_action_hw_stats_get(struct nlattr *hw_stats_attr)
1282 {
1283 	struct nla_bitfield32 hw_stats_bf;
1284 
1285 	/* If the user did not pass the attr, that means he does
1286 	 * not care about the type. Return "any" in that case
1287 	 * which is setting on all supported types.
1288 	 */
1289 	if (!hw_stats_attr)
1290 		return TCA_ACT_HW_STATS_ANY;
1291 	hw_stats_bf = nla_get_bitfield32(hw_stats_attr);
1292 	return hw_stats_bf.value;
1293 }
1294 
1295 static const struct nla_policy tcf_action_policy[TCA_ACT_MAX + 1] = {
1296 	[TCA_ACT_KIND]		= { .type = NLA_STRING },
1297 	[TCA_ACT_INDEX]		= { .type = NLA_U32 },
1298 	[TCA_ACT_COOKIE]	= { .type = NLA_BINARY,
1299 				    .len = TC_COOKIE_MAX_SIZE },
1300 	[TCA_ACT_OPTIONS]	= { .type = NLA_NESTED },
1301 	[TCA_ACT_FLAGS]		= NLA_POLICY_BITFIELD32(TCA_ACT_FLAGS_NO_PERCPU_STATS |
1302 							TCA_ACT_FLAGS_SKIP_HW |
1303 							TCA_ACT_FLAGS_SKIP_SW),
1304 	[TCA_ACT_HW_STATS]	= NLA_POLICY_BITFIELD32(TCA_ACT_HW_STATS_ANY),
1305 };
1306 
tcf_idr_insert_many(struct tc_action * actions[],int init_res[])1307 void tcf_idr_insert_many(struct tc_action *actions[], int init_res[])
1308 {
1309 	struct tc_action *a;
1310 	int i;
1311 
1312 	tcf_act_for_each_action(i, a, actions) {
1313 		struct tcf_idrinfo *idrinfo;
1314 
1315 		if (init_res[i] == ACT_P_BOUND)
1316 			continue;
1317 
1318 		idrinfo = a->idrinfo;
1319 		mutex_lock(&idrinfo->lock);
1320 		/* Replace ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */
1321 		idr_replace(&idrinfo->action_idr, a, a->tcfa_index);
1322 		mutex_unlock(&idrinfo->lock);
1323 	}
1324 }
1325 
tc_action_load_ops(struct nlattr * nla,u32 flags,struct netlink_ext_ack * extack)1326 struct tc_action_ops *tc_action_load_ops(struct nlattr *nla, u32 flags,
1327 					 struct netlink_ext_ack *extack)
1328 {
1329 	bool police = flags & TCA_ACT_FLAGS_POLICE;
1330 	struct nlattr *tb[TCA_ACT_MAX + 1];
1331 	struct tc_action_ops *a_o;
1332 	char act_name[IFNAMSIZ];
1333 	struct nlattr *kind;
1334 	int err;
1335 
1336 	if (!police) {
1337 		err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1338 						  tcf_action_policy, extack);
1339 		if (err < 0)
1340 			return ERR_PTR(err);
1341 		err = -EINVAL;
1342 		kind = tb[TCA_ACT_KIND];
1343 		if (!kind) {
1344 			NL_SET_ERR_MSG(extack, "TC action kind must be specified");
1345 			return ERR_PTR(err);
1346 		}
1347 		if (nla_strscpy(act_name, kind, IFNAMSIZ) < 0) {
1348 			NL_SET_ERR_MSG(extack, "TC action name too long");
1349 			return ERR_PTR(err);
1350 		}
1351 	} else {
1352 		if (strscpy(act_name, "police", IFNAMSIZ) < 0) {
1353 			NL_SET_ERR_MSG(extack, "TC action name too long");
1354 			return ERR_PTR(-EINVAL);
1355 		}
1356 	}
1357 
1358 	a_o = tc_lookup_action_n(act_name);
1359 	if (a_o == NULL) {
1360 #ifdef CONFIG_MODULES
1361 		bool rtnl_held = !(flags & TCA_ACT_FLAGS_NO_RTNL);
1362 
1363 		if (rtnl_held)
1364 			rtnl_unlock();
1365 		request_module(NET_ACT_ALIAS_PREFIX "%s", act_name);
1366 		if (rtnl_held)
1367 			rtnl_lock();
1368 
1369 		a_o = tc_lookup_action_n(act_name);
1370 
1371 		/* We dropped the RTNL semaphore in order to
1372 		 * perform the module load.  So, even if we
1373 		 * succeeded in loading the module we have to
1374 		 * tell the caller to replay the request.  We
1375 		 * indicate this using -EAGAIN.
1376 		 */
1377 		if (a_o != NULL) {
1378 			module_put(a_o->owner);
1379 			return ERR_PTR(-EAGAIN);
1380 		}
1381 #endif
1382 		NL_SET_ERR_MSG(extack, "Failed to load TC action module");
1383 		return ERR_PTR(-ENOENT);
1384 	}
1385 
1386 	return a_o;
1387 }
1388 
tcf_action_init_1(struct net * net,struct tcf_proto * tp,struct nlattr * nla,struct nlattr * est,struct tc_action_ops * a_o,int * init_res,u32 flags,struct netlink_ext_ack * extack)1389 struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
1390 				    struct nlattr *nla, struct nlattr *est,
1391 				    struct tc_action_ops *a_o, int *init_res,
1392 				    u32 flags, struct netlink_ext_ack *extack)
1393 {
1394 	bool police = flags & TCA_ACT_FLAGS_POLICE;
1395 	struct nla_bitfield32 userflags = { 0, 0 };
1396 	struct tc_cookie *user_cookie = NULL;
1397 	u8 hw_stats = TCA_ACT_HW_STATS_ANY;
1398 	struct nlattr *tb[TCA_ACT_MAX + 1];
1399 	struct tc_action *a;
1400 	int err;
1401 
1402 	/* backward compatibility for policer */
1403 	if (!police) {
1404 		err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1405 						  tcf_action_policy, extack);
1406 		if (err < 0)
1407 			return ERR_PTR(err);
1408 		if (tb[TCA_ACT_COOKIE]) {
1409 			user_cookie = nla_memdup_cookie(tb);
1410 			if (!user_cookie) {
1411 				NL_SET_ERR_MSG(extack, "No memory to generate TC cookie");
1412 				err = -ENOMEM;
1413 				goto err_out;
1414 			}
1415 		}
1416 		hw_stats = tcf_action_hw_stats_get(tb[TCA_ACT_HW_STATS]);
1417 		if (tb[TCA_ACT_FLAGS]) {
1418 			userflags = nla_get_bitfield32(tb[TCA_ACT_FLAGS]);
1419 			if (!tc_act_flags_valid(userflags.value)) {
1420 				err = -EINVAL;
1421 				goto err_out;
1422 			}
1423 		}
1424 
1425 		err = a_o->init(net, tb[TCA_ACT_OPTIONS], est, &a, tp,
1426 				userflags.value | flags, extack);
1427 	} else {
1428 		err = a_o->init(net, nla, est, &a, tp, userflags.value | flags,
1429 				extack);
1430 	}
1431 	if (err < 0)
1432 		goto err_out;
1433 	*init_res = err;
1434 
1435 	if (!police && tb[TCA_ACT_COOKIE])
1436 		tcf_set_action_cookie(&a->user_cookie, user_cookie);
1437 
1438 	if (!police)
1439 		a->hw_stats = hw_stats;
1440 
1441 	return a;
1442 
1443 err_out:
1444 	if (user_cookie) {
1445 		kfree(user_cookie->data);
1446 		kfree(user_cookie);
1447 	}
1448 	return ERR_PTR(err);
1449 }
1450 
tc_act_bind(u32 flags)1451 static bool tc_act_bind(u32 flags)
1452 {
1453 	return !!(flags & TCA_ACT_FLAGS_BIND);
1454 }
1455 
1456 /* Returns numbers of initialized actions or negative error. */
1457 
tcf_action_init(struct net * net,struct tcf_proto * tp,struct nlattr * nla,struct nlattr * est,struct tc_action * actions[],int init_res[],size_t * attr_size,u32 flags,u32 fl_flags,struct netlink_ext_ack * extack)1458 int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla,
1459 		    struct nlattr *est, struct tc_action *actions[],
1460 		    int init_res[], size_t *attr_size,
1461 		    u32 flags, u32 fl_flags,
1462 		    struct netlink_ext_ack *extack)
1463 {
1464 	struct tc_action_ops *ops[TCA_ACT_MAX_PRIO] = {};
1465 	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1466 	struct tc_action *act;
1467 	size_t sz = 0;
1468 	int err;
1469 	int i;
1470 
1471 	err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX_PRIO, nla, NULL,
1472 					  extack);
1473 	if (err < 0)
1474 		return err;
1475 
1476 	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1477 		struct tc_action_ops *a_o;
1478 
1479 		a_o = tc_action_load_ops(tb[i], flags, extack);
1480 		if (IS_ERR(a_o)) {
1481 			err = PTR_ERR(a_o);
1482 			goto err_mod;
1483 		}
1484 		ops[i - 1] = a_o;
1485 	}
1486 
1487 	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1488 		act = tcf_action_init_1(net, tp, tb[i], est, ops[i - 1],
1489 					&init_res[i - 1], flags, extack);
1490 		if (IS_ERR(act)) {
1491 			err = PTR_ERR(act);
1492 			goto err;
1493 		}
1494 		sz += tcf_action_fill_size(act);
1495 		/* Start from index 0 */
1496 		actions[i - 1] = act;
1497 		if (tc_act_bind(flags)) {
1498 			bool skip_sw = tc_skip_sw(fl_flags);
1499 			bool skip_hw = tc_skip_hw(fl_flags);
1500 
1501 			if (tc_act_bind(act->tcfa_flags))
1502 				continue;
1503 			if (skip_sw != tc_act_skip_sw(act->tcfa_flags) ||
1504 			    skip_hw != tc_act_skip_hw(act->tcfa_flags)) {
1505 				NL_SET_ERR_MSG(extack,
1506 					       "Mismatch between action and filter offload flags");
1507 				err = -EINVAL;
1508 				goto err;
1509 			}
1510 		} else {
1511 			err = tcf_action_offload_add(act, extack);
1512 			if (tc_act_skip_sw(act->tcfa_flags) && err)
1513 				goto err;
1514 		}
1515 	}
1516 
1517 	/* We have to commit them all together, because if any error happened in
1518 	 * between, we could not handle the failure gracefully.
1519 	 */
1520 	tcf_idr_insert_many(actions, init_res);
1521 
1522 	*attr_size = tcf_action_full_attrs_size(sz);
1523 	err = i - 1;
1524 	goto err_mod;
1525 
1526 err:
1527 	tcf_action_destroy(actions, flags & TCA_ACT_FLAGS_BIND);
1528 err_mod:
1529 	for (i = 0; i < TCA_ACT_MAX_PRIO && ops[i]; i++)
1530 		module_put(ops[i]->owner);
1531 	return err;
1532 }
1533 
tcf_action_update_stats(struct tc_action * a,u64 bytes,u64 packets,u64 drops,bool hw)1534 void tcf_action_update_stats(struct tc_action *a, u64 bytes, u64 packets,
1535 			     u64 drops, bool hw)
1536 {
1537 	if (a->cpu_bstats) {
1538 		_bstats_update(this_cpu_ptr(a->cpu_bstats), bytes, packets);
1539 
1540 		this_cpu_ptr(a->cpu_qstats)->drops += drops;
1541 
1542 		if (hw)
1543 			_bstats_update(this_cpu_ptr(a->cpu_bstats_hw),
1544 				       bytes, packets);
1545 		return;
1546 	}
1547 
1548 	_bstats_update(&a->tcfa_bstats, bytes, packets);
1549 	a->tcfa_qstats.drops += drops;
1550 	if (hw)
1551 		_bstats_update(&a->tcfa_bstats_hw, bytes, packets);
1552 }
1553 EXPORT_SYMBOL(tcf_action_update_stats);
1554 
tcf_action_copy_stats(struct sk_buff * skb,struct tc_action * p,int compat_mode)1555 int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *p,
1556 			  int compat_mode)
1557 {
1558 	int err = 0;
1559 	struct gnet_dump d;
1560 
1561 	if (p == NULL)
1562 		goto errout;
1563 
1564 	/* compat_mode being true specifies a call that is supposed
1565 	 * to add additional backward compatibility statistic TLVs.
1566 	 */
1567 	if (compat_mode) {
1568 		if (p->type == TCA_OLD_COMPAT)
1569 			err = gnet_stats_start_copy_compat(skb, 0,
1570 							   TCA_STATS,
1571 							   TCA_XSTATS,
1572 							   &p->tcfa_lock, &d,
1573 							   TCA_PAD);
1574 		else
1575 			return 0;
1576 	} else
1577 		err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
1578 					    &p->tcfa_lock, &d, TCA_ACT_PAD);
1579 
1580 	if (err < 0)
1581 		goto errout;
1582 
1583 	if (gnet_stats_copy_basic(&d, p->cpu_bstats,
1584 				  &p->tcfa_bstats, false) < 0 ||
1585 	    gnet_stats_copy_basic_hw(&d, p->cpu_bstats_hw,
1586 				     &p->tcfa_bstats_hw, false) < 0 ||
1587 	    gnet_stats_copy_rate_est(&d, &p->tcfa_rate_est) < 0 ||
1588 	    gnet_stats_copy_queue(&d, p->cpu_qstats,
1589 				  &p->tcfa_qstats,
1590 				  p->tcfa_qstats.qlen) < 0)
1591 		goto errout;
1592 
1593 	if (gnet_stats_finish_copy(&d) < 0)
1594 		goto errout;
1595 
1596 	return 0;
1597 
1598 errout:
1599 	return -1;
1600 }
1601 
tca_get_fill(struct sk_buff * skb,struct tc_action * actions[],u32 portid,u32 seq,u16 flags,int event,int bind,int ref,struct netlink_ext_ack * extack)1602 static int tca_get_fill(struct sk_buff *skb, struct tc_action *actions[],
1603 			u32 portid, u32 seq, u16 flags, int event, int bind,
1604 			int ref, struct netlink_ext_ack *extack)
1605 {
1606 	struct tcamsg *t;
1607 	struct nlmsghdr *nlh;
1608 	unsigned char *b = skb_tail_pointer(skb);
1609 	struct nlattr *nest;
1610 
1611 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*t), flags);
1612 	if (!nlh)
1613 		goto out_nlmsg_trim;
1614 	t = nlmsg_data(nlh);
1615 	t->tca_family = AF_UNSPEC;
1616 	t->tca__pad1 = 0;
1617 	t->tca__pad2 = 0;
1618 
1619 	if (extack && extack->_msg &&
1620 	    nla_put_string(skb, TCA_ROOT_EXT_WARN_MSG, extack->_msg))
1621 		goto out_nlmsg_trim;
1622 
1623 	nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
1624 	if (!nest)
1625 		goto out_nlmsg_trim;
1626 
1627 	if (tcf_action_dump(skb, actions, bind, ref, false) < 0)
1628 		goto out_nlmsg_trim;
1629 
1630 	nla_nest_end(skb, nest);
1631 
1632 	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1633 
1634 	return skb->len;
1635 
1636 out_nlmsg_trim:
1637 	nlmsg_trim(skb, b);
1638 	return -1;
1639 }
1640 
1641 static int
tcf_get_notify(struct net * net,u32 portid,struct nlmsghdr * n,struct tc_action * actions[],int event,struct netlink_ext_ack * extack)1642 tcf_get_notify(struct net *net, u32 portid, struct nlmsghdr *n,
1643 	       struct tc_action *actions[], int event,
1644 	       struct netlink_ext_ack *extack)
1645 {
1646 	struct sk_buff *skb;
1647 
1648 	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1649 	if (!skb)
1650 		return -ENOBUFS;
1651 	if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, event,
1652 			 0, 1, NULL) <= 0) {
1653 		NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1654 		kfree_skb(skb);
1655 		return -EINVAL;
1656 	}
1657 
1658 	return rtnl_unicast(skb, net, portid);
1659 }
1660 
tcf_action_get_1(struct net * net,struct nlattr * nla,struct nlmsghdr * n,u32 portid,struct netlink_ext_ack * extack)1661 static struct tc_action *tcf_action_get_1(struct net *net, struct nlattr *nla,
1662 					  struct nlmsghdr *n, u32 portid,
1663 					  struct netlink_ext_ack *extack)
1664 {
1665 	struct nlattr *tb[TCA_ACT_MAX + 1];
1666 	const struct tc_action_ops *ops;
1667 	struct tc_action *a;
1668 	int index;
1669 	int err;
1670 
1671 	err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1672 					  tcf_action_policy, extack);
1673 	if (err < 0)
1674 		goto err_out;
1675 
1676 	err = -EINVAL;
1677 	if (tb[TCA_ACT_INDEX] == NULL ||
1678 	    nla_len(tb[TCA_ACT_INDEX]) < sizeof(index)) {
1679 		NL_SET_ERR_MSG(extack, "Invalid TC action index value");
1680 		goto err_out;
1681 	}
1682 	index = nla_get_u32(tb[TCA_ACT_INDEX]);
1683 
1684 	err = -EINVAL;
1685 	ops = tc_lookup_action(tb[TCA_ACT_KIND]);
1686 	if (!ops) { /* could happen in batch of actions */
1687 		NL_SET_ERR_MSG(extack, "Specified TC action kind not found");
1688 		goto err_out;
1689 	}
1690 	err = -ENOENT;
1691 	if (__tcf_idr_search(net, ops, &a, index) == 0) {
1692 		NL_SET_ERR_MSG(extack, "TC action with specified index not found");
1693 		goto err_mod;
1694 	}
1695 
1696 	module_put(ops->owner);
1697 	return a;
1698 
1699 err_mod:
1700 	module_put(ops->owner);
1701 err_out:
1702 	return ERR_PTR(err);
1703 }
1704 
tca_action_flush(struct net * net,struct nlattr * nla,struct nlmsghdr * n,u32 portid,struct netlink_ext_ack * extack)1705 static int tca_action_flush(struct net *net, struct nlattr *nla,
1706 			    struct nlmsghdr *n, u32 portid,
1707 			    struct netlink_ext_ack *extack)
1708 {
1709 	struct sk_buff *skb;
1710 	unsigned char *b;
1711 	struct nlmsghdr *nlh;
1712 	struct tcamsg *t;
1713 	struct netlink_callback dcb;
1714 	struct nlattr *nest;
1715 	struct nlattr *tb[TCA_ACT_MAX + 1];
1716 	const struct tc_action_ops *ops;
1717 	struct nlattr *kind;
1718 	int err = -ENOMEM;
1719 
1720 	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1721 	if (!skb)
1722 		return err;
1723 
1724 	b = skb_tail_pointer(skb);
1725 
1726 	err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla,
1727 					  tcf_action_policy, extack);
1728 	if (err < 0)
1729 		goto err_out;
1730 
1731 	err = -EINVAL;
1732 	kind = tb[TCA_ACT_KIND];
1733 	ops = tc_lookup_action(kind);
1734 	if (!ops) { /*some idjot trying to flush unknown action */
1735 		NL_SET_ERR_MSG(extack, "Cannot flush unknown TC action");
1736 		goto err_out;
1737 	}
1738 
1739 	nlh = nlmsg_put(skb, portid, n->nlmsg_seq, RTM_DELACTION,
1740 			sizeof(*t), 0);
1741 	if (!nlh) {
1742 		NL_SET_ERR_MSG(extack, "Failed to create TC action flush notification");
1743 		goto out_module_put;
1744 	}
1745 	t = nlmsg_data(nlh);
1746 	t->tca_family = AF_UNSPEC;
1747 	t->tca__pad1 = 0;
1748 	t->tca__pad2 = 0;
1749 
1750 	nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
1751 	if (!nest) {
1752 		NL_SET_ERR_MSG(extack, "Failed to add new netlink message");
1753 		goto out_module_put;
1754 	}
1755 
1756 	err = __tcf_generic_walker(net, skb, &dcb, RTM_DELACTION, ops, extack);
1757 	if (err <= 0) {
1758 		nla_nest_cancel(skb, nest);
1759 		goto out_module_put;
1760 	}
1761 
1762 	nla_nest_end(skb, nest);
1763 
1764 	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1765 	nlh->nlmsg_flags |= NLM_F_ROOT;
1766 	module_put(ops->owner);
1767 	err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1768 			     n->nlmsg_flags & NLM_F_ECHO);
1769 	if (err < 0)
1770 		NL_SET_ERR_MSG(extack, "Failed to send TC action flush notification");
1771 
1772 	return err;
1773 
1774 out_module_put:
1775 	module_put(ops->owner);
1776 err_out:
1777 	kfree_skb(skb);
1778 	return err;
1779 }
1780 
tcf_action_delete(struct net * net,struct tc_action * actions[])1781 static int tcf_action_delete(struct net *net, struct tc_action *actions[])
1782 {
1783 	struct tc_action *a;
1784 	int i;
1785 
1786 	tcf_act_for_each_action(i, a, actions) {
1787 		const struct tc_action_ops *ops = a->ops;
1788 		/* Actions can be deleted concurrently so we must save their
1789 		 * type and id to search again after reference is released.
1790 		 */
1791 		struct tcf_idrinfo *idrinfo = a->idrinfo;
1792 		u32 act_index = a->tcfa_index;
1793 
1794 		actions[i] = NULL;
1795 		if (tcf_action_put(a)) {
1796 			/* last reference, action was deleted concurrently */
1797 			module_put(ops->owner);
1798 		} else {
1799 			int ret;
1800 
1801 			/* now do the delete */
1802 			ret = tcf_idr_delete_index(idrinfo, act_index);
1803 			if (ret < 0)
1804 				return ret;
1805 		}
1806 	}
1807 	return 0;
1808 }
1809 
tcf_reoffload_del_notify_msg(struct net * net,struct tc_action * action)1810 static struct sk_buff *tcf_reoffload_del_notify_msg(struct net *net,
1811 						    struct tc_action *action)
1812 {
1813 	size_t attr_size = tcf_action_fill_size(action);
1814 	struct tc_action *actions[TCA_ACT_MAX_PRIO] = {
1815 		[0] = action,
1816 	};
1817 	struct sk_buff *skb;
1818 
1819 	skb = alloc_skb(max(attr_size, NLMSG_GOODSIZE), GFP_KERNEL);
1820 	if (!skb)
1821 		return ERR_PTR(-ENOBUFS);
1822 
1823 	if (tca_get_fill(skb, actions, 0, 0, 0, RTM_DELACTION, 0, 1, NULL) <= 0) {
1824 		kfree_skb(skb);
1825 		return ERR_PTR(-EINVAL);
1826 	}
1827 
1828 	return skb;
1829 }
1830 
tcf_reoffload_del_notify(struct net * net,struct tc_action * action)1831 static int tcf_reoffload_del_notify(struct net *net, struct tc_action *action)
1832 {
1833 	const struct tc_action_ops *ops = action->ops;
1834 	struct sk_buff *skb;
1835 	int ret;
1836 
1837 	if (!rtnl_notify_needed(net, 0, RTNLGRP_TC)) {
1838 		skb = NULL;
1839 	} else {
1840 		skb = tcf_reoffload_del_notify_msg(net, action);
1841 		if (IS_ERR(skb))
1842 			return PTR_ERR(skb);
1843 	}
1844 
1845 	ret = tcf_idr_release_unsafe(action);
1846 	if (ret == ACT_P_DELETED) {
1847 		module_put(ops->owner);
1848 		ret = rtnetlink_maybe_send(skb, net, 0, RTNLGRP_TC, 0);
1849 	} else {
1850 		kfree_skb(skb);
1851 	}
1852 
1853 	return ret;
1854 }
1855 
tcf_action_reoffload_cb(flow_indr_block_bind_cb_t * cb,void * cb_priv,bool add)1856 int tcf_action_reoffload_cb(flow_indr_block_bind_cb_t *cb,
1857 			    void *cb_priv, bool add)
1858 {
1859 	struct tc_act_pernet_id *id_ptr;
1860 	struct tcf_idrinfo *idrinfo;
1861 	struct tc_action_net *tn;
1862 	struct tc_action *p;
1863 	unsigned int act_id;
1864 	unsigned long tmp;
1865 	unsigned long id;
1866 	struct idr *idr;
1867 	struct net *net;
1868 	int ret;
1869 
1870 	if (!cb)
1871 		return -EINVAL;
1872 
1873 	down_read(&net_rwsem);
1874 	mutex_lock(&act_id_mutex);
1875 
1876 	for_each_net(net) {
1877 		list_for_each_entry(id_ptr, &act_pernet_id_list, list) {
1878 			act_id = id_ptr->id;
1879 			tn = net_generic(net, act_id);
1880 			if (!tn)
1881 				continue;
1882 			idrinfo = tn->idrinfo;
1883 			if (!idrinfo)
1884 				continue;
1885 
1886 			mutex_lock(&idrinfo->lock);
1887 			idr = &idrinfo->action_idr;
1888 			idr_for_each_entry_ul(idr, p, tmp, id) {
1889 				if (IS_ERR(p) || tc_act_bind(p->tcfa_flags))
1890 					continue;
1891 				if (add) {
1892 					tcf_action_offload_add_ex(p, NULL, cb,
1893 								  cb_priv);
1894 					continue;
1895 				}
1896 
1897 				/* cb unregister to update hw count */
1898 				ret = tcf_action_offload_del_ex(p, cb, cb_priv);
1899 				if (ret < 0)
1900 					continue;
1901 				if (tc_act_skip_sw(p->tcfa_flags) &&
1902 				    !tc_act_in_hw(p))
1903 					tcf_reoffload_del_notify(net, p);
1904 			}
1905 			mutex_unlock(&idrinfo->lock);
1906 		}
1907 	}
1908 	mutex_unlock(&act_id_mutex);
1909 	up_read(&net_rwsem);
1910 
1911 	return 0;
1912 }
1913 
tcf_del_notify_msg(struct net * net,struct nlmsghdr * n,struct tc_action * actions[],u32 portid,size_t attr_size,struct netlink_ext_ack * extack)1914 static struct sk_buff *tcf_del_notify_msg(struct net *net, struct nlmsghdr *n,
1915 					  struct tc_action *actions[],
1916 					  u32 portid, size_t attr_size,
1917 					  struct netlink_ext_ack *extack)
1918 {
1919 	struct sk_buff *skb;
1920 
1921 	skb = alloc_skb(max(attr_size, NLMSG_GOODSIZE), GFP_KERNEL);
1922 	if (!skb)
1923 		return ERR_PTR(-ENOBUFS);
1924 
1925 	if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, RTM_DELACTION,
1926 			 0, 2, extack) <= 0) {
1927 		NL_SET_ERR_MSG(extack, "Failed to fill netlink TC action attributes");
1928 		kfree_skb(skb);
1929 		return ERR_PTR(-EINVAL);
1930 	}
1931 
1932 	return skb;
1933 }
1934 
tcf_del_notify(struct net * net,struct nlmsghdr * n,struct tc_action * actions[],u32 portid,size_t attr_size,struct netlink_ext_ack * extack)1935 static int tcf_del_notify(struct net *net, struct nlmsghdr *n,
1936 			  struct tc_action *actions[], u32 portid,
1937 			  size_t attr_size, struct netlink_ext_ack *extack)
1938 {
1939 	struct sk_buff *skb;
1940 	int ret;
1941 
1942 	if (!rtnl_notify_needed(net, n->nlmsg_flags, RTNLGRP_TC)) {
1943 		skb = NULL;
1944 	} else {
1945 		skb = tcf_del_notify_msg(net, n, actions, portid, attr_size,
1946 					 extack);
1947 		if (IS_ERR(skb))
1948 			return PTR_ERR(skb);
1949 	}
1950 
1951 	/* now do the delete */
1952 	ret = tcf_action_delete(net, actions);
1953 	if (ret < 0) {
1954 		NL_SET_ERR_MSG(extack, "Failed to delete TC action");
1955 		kfree_skb(skb);
1956 		return ret;
1957 	}
1958 
1959 	return rtnetlink_maybe_send(skb, net, portid, RTNLGRP_TC,
1960 				    n->nlmsg_flags & NLM_F_ECHO);
1961 }
1962 
1963 static int
tca_action_gd(struct net * net,struct nlattr * nla,struct nlmsghdr * n,u32 portid,int event,struct netlink_ext_ack * extack)1964 tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
1965 	      u32 portid, int event, struct netlink_ext_ack *extack)
1966 {
1967 	int i, ret;
1968 	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1969 	struct tc_action *act;
1970 	size_t attr_size = 0;
1971 	struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
1972 
1973 	ret = nla_parse_nested_deprecated(tb, TCA_ACT_MAX_PRIO, nla, NULL,
1974 					  extack);
1975 	if (ret < 0)
1976 		return ret;
1977 
1978 	if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) {
1979 		if (tb[1])
1980 			return tca_action_flush(net, tb[1], n, portid, extack);
1981 
1982 		NL_SET_ERR_MSG(extack, "Invalid netlink attributes while flushing TC action");
1983 		return -EINVAL;
1984 	}
1985 
1986 	for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1987 		act = tcf_action_get_1(net, tb[i], n, portid, extack);
1988 		if (IS_ERR(act)) {
1989 			ret = PTR_ERR(act);
1990 			goto err;
1991 		}
1992 		attr_size += tcf_action_fill_size(act);
1993 		actions[i - 1] = act;
1994 	}
1995 
1996 	attr_size = tcf_action_full_attrs_size(attr_size);
1997 
1998 	if (event == RTM_GETACTION)
1999 		ret = tcf_get_notify(net, portid, n, actions, event, extack);
2000 	else { /* delete */
2001 		ret = tcf_del_notify(net, n, actions, portid, attr_size, extack);
2002 		if (ret)
2003 			goto err;
2004 		return 0;
2005 	}
2006 err:
2007 	tcf_action_put_many(actions);
2008 	return ret;
2009 }
2010 
tcf_add_notify_msg(struct net * net,struct nlmsghdr * n,struct tc_action * actions[],u32 portid,size_t attr_size,struct netlink_ext_ack * extack)2011 static struct sk_buff *tcf_add_notify_msg(struct net *net, struct nlmsghdr *n,
2012 					  struct tc_action *actions[],
2013 					  u32 portid, size_t attr_size,
2014 					  struct netlink_ext_ack *extack)
2015 {
2016 	struct sk_buff *skb;
2017 
2018 	skb = alloc_skb(max(attr_size, NLMSG_GOODSIZE), GFP_KERNEL);
2019 	if (!skb)
2020 		return ERR_PTR(-ENOBUFS);
2021 
2022 	if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, n->nlmsg_flags,
2023 			 RTM_NEWACTION, 0, 0, extack) <= 0) {
2024 		NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
2025 		kfree_skb(skb);
2026 		return ERR_PTR(-EINVAL);
2027 	}
2028 
2029 	return skb;
2030 }
2031 
tcf_add_notify(struct net * net,struct nlmsghdr * n,struct tc_action * actions[],u32 portid,size_t attr_size,struct netlink_ext_ack * extack)2032 static int tcf_add_notify(struct net *net, struct nlmsghdr *n,
2033 			  struct tc_action *actions[], u32 portid,
2034 			  size_t attr_size, struct netlink_ext_ack *extack)
2035 {
2036 	struct sk_buff *skb;
2037 
2038 	if (!rtnl_notify_needed(net, n->nlmsg_flags, RTNLGRP_TC)) {
2039 		skb = NULL;
2040 	} else {
2041 		skb = tcf_add_notify_msg(net, n, actions, portid, attr_size,
2042 					 extack);
2043 		if (IS_ERR(skb))
2044 			return PTR_ERR(skb);
2045 	}
2046 
2047 	return rtnetlink_maybe_send(skb, net, portid, RTNLGRP_TC,
2048 				    n->nlmsg_flags & NLM_F_ECHO);
2049 }
2050 
tcf_action_add(struct net * net,struct nlattr * nla,struct nlmsghdr * n,u32 portid,u32 flags,struct netlink_ext_ack * extack)2051 static int tcf_action_add(struct net *net, struct nlattr *nla,
2052 			  struct nlmsghdr *n, u32 portid, u32 flags,
2053 			  struct netlink_ext_ack *extack)
2054 {
2055 	size_t attr_size = 0;
2056 	int loop, ret;
2057 	struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
2058 	int init_res[TCA_ACT_MAX_PRIO] = {};
2059 
2060 	for (loop = 0; loop < 10; loop++) {
2061 		ret = tcf_action_init(net, NULL, nla, NULL, actions, init_res,
2062 				      &attr_size, flags, 0, extack);
2063 		if (ret != -EAGAIN)
2064 			break;
2065 	}
2066 
2067 	if (ret < 0)
2068 		return ret;
2069 
2070 	ret = tcf_add_notify(net, n, actions, portid, attr_size, extack);
2071 
2072 	/* only put bound actions */
2073 	tca_put_bound_many(actions, init_res);
2074 
2075 	return ret;
2076 }
2077 
2078 static const struct nla_policy tcaa_policy[TCA_ROOT_MAX + 1] = {
2079 	[TCA_ROOT_FLAGS] = NLA_POLICY_BITFIELD32(TCA_ACT_FLAG_LARGE_DUMP_ON |
2080 						 TCA_ACT_FLAG_TERSE_DUMP),
2081 	[TCA_ROOT_TIME_DELTA]      = { .type = NLA_U32 },
2082 };
2083 
tc_ctl_action(struct sk_buff * skb,struct nlmsghdr * n,struct netlink_ext_ack * extack)2084 static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n,
2085 			 struct netlink_ext_ack *extack)
2086 {
2087 	struct net *net = sock_net(skb->sk);
2088 	struct nlattr *tca[TCA_ROOT_MAX + 1];
2089 	u32 portid = NETLINK_CB(skb).portid;
2090 	u32 flags = 0;
2091 	int ret = 0;
2092 
2093 	if ((n->nlmsg_type != RTM_GETACTION) &&
2094 	    !netlink_capable(skb, CAP_NET_ADMIN))
2095 		return -EPERM;
2096 
2097 	ret = nlmsg_parse_deprecated(n, sizeof(struct tcamsg), tca,
2098 				     TCA_ROOT_MAX, NULL, extack);
2099 	if (ret < 0)
2100 		return ret;
2101 
2102 	if (tca[TCA_ACT_TAB] == NULL) {
2103 		NL_SET_ERR_MSG(extack, "Netlink action attributes missing");
2104 		return -EINVAL;
2105 	}
2106 
2107 	/* n->nlmsg_flags & NLM_F_CREATE */
2108 	switch (n->nlmsg_type) {
2109 	case RTM_NEWACTION:
2110 		/* we are going to assume all other flags
2111 		 * imply create only if it doesn't exist
2112 		 * Note that CREATE | EXCL implies that
2113 		 * but since we want avoid ambiguity (eg when flags
2114 		 * is zero) then just set this
2115 		 */
2116 		if (n->nlmsg_flags & NLM_F_REPLACE)
2117 			flags = TCA_ACT_FLAGS_REPLACE;
2118 		ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, portid, flags,
2119 				     extack);
2120 		break;
2121 	case RTM_DELACTION:
2122 		ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
2123 				    portid, RTM_DELACTION, extack);
2124 		break;
2125 	case RTM_GETACTION:
2126 		ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
2127 				    portid, RTM_GETACTION, extack);
2128 		break;
2129 	default:
2130 		BUG();
2131 	}
2132 
2133 	return ret;
2134 }
2135 
find_dump_kind(struct nlattr ** nla)2136 static struct nlattr *find_dump_kind(struct nlattr **nla)
2137 {
2138 	struct nlattr *tb1, *tb2[TCA_ACT_MAX + 1];
2139 	struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
2140 	struct nlattr *kind;
2141 
2142 	tb1 = nla[TCA_ACT_TAB];
2143 	if (tb1 == NULL)
2144 		return NULL;
2145 
2146 	if (nla_parse_deprecated(tb, TCA_ACT_MAX_PRIO, nla_data(tb1), NLMSG_ALIGN(nla_len(tb1)), NULL, NULL) < 0)
2147 		return NULL;
2148 
2149 	if (tb[1] == NULL)
2150 		return NULL;
2151 	if (nla_parse_nested_deprecated(tb2, TCA_ACT_MAX, tb[1], tcf_action_policy, NULL) < 0)
2152 		return NULL;
2153 	kind = tb2[TCA_ACT_KIND];
2154 
2155 	return kind;
2156 }
2157 
tc_dump_action(struct sk_buff * skb,struct netlink_callback * cb)2158 static int tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
2159 {
2160 	struct net *net = sock_net(skb->sk);
2161 	struct nlmsghdr *nlh;
2162 	unsigned char *b = skb_tail_pointer(skb);
2163 	struct nlattr *nest;
2164 	struct tc_action_ops *a_o;
2165 	int ret = 0;
2166 	struct tcamsg *t = (struct tcamsg *) nlmsg_data(cb->nlh);
2167 	struct nlattr *tb[TCA_ROOT_MAX + 1];
2168 	struct nlattr *count_attr = NULL;
2169 	unsigned long jiffy_since = 0;
2170 	struct nlattr *kind = NULL;
2171 	struct nla_bitfield32 bf;
2172 	u32 msecs_since = 0;
2173 	u32 act_count = 0;
2174 
2175 	ret = nlmsg_parse_deprecated(cb->nlh, sizeof(struct tcamsg), tb,
2176 				     TCA_ROOT_MAX, tcaa_policy, cb->extack);
2177 	if (ret < 0)
2178 		return ret;
2179 
2180 	kind = find_dump_kind(tb);
2181 	if (kind == NULL) {
2182 		pr_info("tc_dump_action: action bad kind\n");
2183 		return 0;
2184 	}
2185 
2186 	a_o = tc_lookup_action(kind);
2187 	if (a_o == NULL)
2188 		return 0;
2189 
2190 	cb->args[2] = 0;
2191 	if (tb[TCA_ROOT_FLAGS]) {
2192 		bf = nla_get_bitfield32(tb[TCA_ROOT_FLAGS]);
2193 		cb->args[2] = bf.value;
2194 	}
2195 
2196 	if (tb[TCA_ROOT_TIME_DELTA]) {
2197 		msecs_since = nla_get_u32(tb[TCA_ROOT_TIME_DELTA]);
2198 	}
2199 
2200 	nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
2201 			cb->nlh->nlmsg_type, sizeof(*t), 0);
2202 	if (!nlh)
2203 		goto out_module_put;
2204 
2205 	if (msecs_since)
2206 		jiffy_since = jiffies - msecs_to_jiffies(msecs_since);
2207 
2208 	t = nlmsg_data(nlh);
2209 	t->tca_family = AF_UNSPEC;
2210 	t->tca__pad1 = 0;
2211 	t->tca__pad2 = 0;
2212 	cb->args[3] = jiffy_since;
2213 	count_attr = nla_reserve(skb, TCA_ROOT_COUNT, sizeof(u32));
2214 	if (!count_attr)
2215 		goto out_module_put;
2216 
2217 	nest = nla_nest_start_noflag(skb, TCA_ACT_TAB);
2218 	if (nest == NULL)
2219 		goto out_module_put;
2220 
2221 	ret = __tcf_generic_walker(net, skb, cb, RTM_GETACTION, a_o, NULL);
2222 	if (ret < 0)
2223 		goto out_module_put;
2224 
2225 	if (ret > 0) {
2226 		nla_nest_end(skb, nest);
2227 		ret = skb->len;
2228 		act_count = cb->args[1];
2229 		memcpy(nla_data(count_attr), &act_count, sizeof(u32));
2230 		cb->args[1] = 0;
2231 	} else
2232 		nlmsg_trim(skb, b);
2233 
2234 	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
2235 	if (NETLINK_CB(cb->skb).portid && ret)
2236 		nlh->nlmsg_flags |= NLM_F_MULTI;
2237 	module_put(a_o->owner);
2238 	return skb->len;
2239 
2240 out_module_put:
2241 	module_put(a_o->owner);
2242 	nlmsg_trim(skb, b);
2243 	return skb->len;
2244 }
2245 
tc_action_init(void)2246 static int __init tc_action_init(void)
2247 {
2248 	rtnl_register(PF_UNSPEC, RTM_NEWACTION, tc_ctl_action, NULL, 0);
2249 	rtnl_register(PF_UNSPEC, RTM_DELACTION, tc_ctl_action, NULL, 0);
2250 	rtnl_register(PF_UNSPEC, RTM_GETACTION, tc_ctl_action, tc_dump_action,
2251 		      0);
2252 
2253 	return 0;
2254 }
2255 
2256 subsys_initcall(tc_action_init);
2257