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