net/sched/act_api.c

   1 /*
   2  * net/sched/act_api.c  Packet action API.
   3  *
   4  *              This program is free software; you can redistribute it and/or
   5  *              modify it under the terms of the GNU General Public License
   6  *              as published by the Free Software Foundation; either version
   7  *              2 of the License, or (at your option) any later version.
   8  *
   9  * Author:      Jamal Hadi Salim
  10  *
  11  *
  12  */
  13
  14 #include <linux/types.h>
  15 #include <linux/kernel.h>
  16 #include <linux/string.h>
  17 #include <linux/errno.h>
  18 #include <linux/slab.h>
  19 #include <linux/skbuff.h>
  20 #include <linux/init.h>
  21 #include <linux/kmod.h>
  22 #include <linux/err.h>
  23 #include <linux/module.h>
  24 #include <linux/rhashtable.h>
  25 #include <linux/list.h>
  26 #include <net/net_namespace.h>
  27 #include <net/sock.h>
  28 #include <net/sch_generic.h>
  29 #include <net/pkt_cls.h>
  30 #include <net/act_api.h>
  31 #include <net/netlink.h>
  32
  33 static int tcf_action_goto_chain_init(struct tc_action *a, struct tcf_proto *tp)
  34 {
  35         u32 chain_index = a->tcfa_action & TC_ACT_EXT_VAL_MASK;
  36
  37         if (!tp)
  38                 return -EINVAL;
  39         a->goto_chain = tcf_chain_get(tp->chain->block, chain_index, true);
  40         if (!a->goto_chain)
  41                 return -ENOMEM;
  42         return 0;
  43 }
  44
  45 static void tcf_action_goto_chain_fini(struct tc_action *a)
  46 {
  47         tcf_chain_put(a->goto_chain);
  48 }
  49
  50 static void tcf_action_goto_chain_exec(const struct tc_action *a,
  51                                        struct tcf_result *res)
  52 {
  53         const struct tcf_chain *chain = a->goto_chain;
  54
  55         res->goto_tp = rcu_dereference_bh(chain->filter_chain);
  56 }
  57
  58 /* XXX: For standalone actions, we don't need a RCU grace period either, because
  59  * actions are always connected to filters and filters are already destroyed in
  60  * RCU callbacks, so after a RCU grace period actions are already disconnected
  61  * from filters. Readers later can not find us.
  62  */
  63 static void free_tcf(struct tc_action *p)
  64 {
  65         free_percpu(p->cpu_bstats);
  66         free_percpu(p->cpu_qstats);
  67
  68         if (p->act_cookie) {
  69                 kfree(p->act_cookie->data);
  70                 kfree(p->act_cookie);
  71         }
  72         if (p->goto_chain)
  73                 tcf_action_goto_chain_fini(p);
  74
  75         kfree(p);
  76 }
  77
  78 static void tcf_idr_remove(struct tcf_idrinfo *idrinfo, struct tc_action *p)
  79 {
  80         spin_lock(&idrinfo->lock);
  81         idr_remove(&idrinfo->action_idr, p->tcfa_index);
  82         spin_unlock(&idrinfo->lock);
  83         gen_kill_estimator(&p->tcfa_rate_est);
  84         free_tcf(p);
  85 }
  86
  87 int __tcf_idr_release(struct tc_action *p, bool bind, bool strict)
  88 {
  89         int ret = 0;
  90
  91         ASSERT_RTNL();
  92
  93         if (p) {
  94                 if (bind)
  95                         p->tcfa_bindcnt--;
  96                 else if (strict && p->tcfa_bindcnt > 0)
  97                         return -EPERM;
  98
  99                 p->tcfa_refcnt--;
 100                 if (p->tcfa_bindcnt <= 0 && p->tcfa_refcnt <= 0) {
 101                         if (p->ops->cleanup)
 102                                 p->ops->cleanup(p);
 103                         tcf_idr_remove(p->idrinfo, p);
 104                         ret = ACT_P_DELETED;
 105                 }
 106         }
 107
 108         return ret;
 109 }
 110 EXPORT_SYMBOL(__tcf_idr_release);
 111
 112 static size_t tcf_action_shared_attrs_size(const struct tc_action *act)
 113 {
 114         u32 cookie_len = 0;
 115
 116         if (act->act_cookie)
 117                 cookie_len = nla_total_size(act->act_cookie->len);
 118
 119         return  nla_total_size(0) /* action number nested */
 120                 + nla_total_size(IFNAMSIZ) /* TCA_ACT_KIND */
 121                 + cookie_len /* TCA_ACT_COOKIE */
 122                 + nla_total_size(0) /* TCA_ACT_STATS nested */
 123                 /* TCA_STATS_BASIC */
 124                 + nla_total_size_64bit(sizeof(struct gnet_stats_basic))
 125                 /* TCA_STATS_QUEUE */
 126                 + nla_total_size_64bit(sizeof(struct gnet_stats_queue))
 127                 + nla_total_size(0) /* TCA_OPTIONS nested */
 128                 + nla_total_size(sizeof(struct tcf_t)); /* TCA_GACT_TM */
 129 }
 130
 131 static size_t tcf_action_full_attrs_size(size_t sz)
 132 {
 133         return NLMSG_HDRLEN                     /* struct nlmsghdr */
 134                 + sizeof(struct tcamsg)
 135                 + nla_total_size(0)             /* TCA_ACT_TAB nested */
 136                 + sz;
 137 }
 138
 139 static size_t tcf_action_fill_size(const struct tc_action *act)
 140 {
 141         size_t sz = tcf_action_shared_attrs_size(act);
 142
 143         if (act->ops->get_fill_size)
 144                 return act->ops->get_fill_size(act) + sz;
 145         return sz;
 146 }
 147
 148 static int tcf_dump_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb,
 149                            struct netlink_callback *cb)
 150 {
 151         int err = 0, index = -1, s_i = 0, n_i = 0;
 152         u32 act_flags = cb->args[2];
 153         unsigned long jiffy_since = cb->args[3];
 154         struct nlattr *nest;
 155         struct idr *idr = &idrinfo->action_idr;
 156         struct tc_action *p;
 157         unsigned long id = 1;
 158
 159         spin_lock(&idrinfo->lock);
 160
 161         s_i = cb->args[0];
 162
 163         idr_for_each_entry_ul(idr, p, id) {
 164                 index++;
 165                 if (index < s_i)
 166                         continue;
 167
 168                 if (jiffy_since &&
 169                     time_after(jiffy_since,
 170                                (unsigned long)p->tcfa_tm.lastuse))
 171                         continue;
 172
 173                 nest = nla_nest_start(skb, n_i);
 174                 if (!nest) {
 175                         index--;
 176                         goto nla_put_failure;
 177                 }
 178                 err = tcf_action_dump_1(skb, p, 0, 0);
 179                 if (err < 0) {
 180                         index--;
 181                         nlmsg_trim(skb, nest);
 182                         goto done;
 183                 }
 184                 nla_nest_end(skb, nest);
 185                 n_i++;
 186                 if (!(act_flags & TCA_FLAG_LARGE_DUMP_ON) &&
 187                     n_i >= TCA_ACT_MAX_PRIO)
 188                         goto done;
 189         }
 190 done:
 191         if (index >= 0)
 192                 cb->args[0] = index + 1;
 193
 194         spin_unlock(&idrinfo->lock);
 195         if (n_i) {
 196                 if (act_flags & TCA_FLAG_LARGE_DUMP_ON)
 197                         cb->args[1] = n_i;
 198         }
 199         return n_i;
 200
 201 nla_put_failure:
 202         nla_nest_cancel(skb, nest);
 203         goto done;
 204 }
 205
 206 static int tcf_del_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb,
 207                           const struct tc_action_ops *ops)
 208 {
 209         struct nlattr *nest;
 210         int n_i = 0;
 211         int ret = -EINVAL;
 212         struct idr *idr = &idrinfo->action_idr;
 213         struct tc_action *p;
 214         unsigned long id = 1;
 215
 216         nest = nla_nest_start(skb, 0);
 217         if (nest == NULL)
 218                 goto nla_put_failure;
 219         if (nla_put_string(skb, TCA_KIND, ops->kind))
 220                 goto nla_put_failure;
 221
 222         idr_for_each_entry_ul(idr, p, id) {
 223                 ret = __tcf_idr_release(p, false, true);
 224                 if (ret == ACT_P_DELETED) {
 225                         module_put(ops->owner);
 226                         n_i++;
 227                 } else if (ret < 0) {
 228                         goto nla_put_failure;
 229                 }
 230         }
 231         if (nla_put_u32(skb, TCA_FCNT, n_i))
 232                 goto nla_put_failure;
 233         nla_nest_end(skb, nest);
 234
 235         return n_i;
 236 nla_put_failure:
 237         nla_nest_cancel(skb, nest);
 238         return ret;
 239 }
 240
 241 int tcf_generic_walker(struct tc_action_net *tn, struct sk_buff *skb,
 242                        struct netlink_callback *cb, int type,
 243                        const struct tc_action_ops *ops,
 244                        struct netlink_ext_ack *extack)
 245 {
 246         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 247
 248         if (type == RTM_DELACTION) {
 249                 return tcf_del_walker(idrinfo, skb, ops);
 250         } else if (type == RTM_GETACTION) {
 251                 return tcf_dump_walker(idrinfo, skb, cb);
 252         } else {
 253                 WARN(1, "tcf_generic_walker: unknown command %d\n", type);
 254                 NL_SET_ERR_MSG(extack, "tcf_generic_walker: unknown command");
 255                 return -EINVAL;
 256         }
 257 }
 258 EXPORT_SYMBOL(tcf_generic_walker);
 259
 260 static struct tc_action *tcf_idr_lookup(u32 index, struct tcf_idrinfo *idrinfo)
 261 {
 262         struct tc_action *p = NULL;
 263
 264         spin_lock(&idrinfo->lock);
 265         p = idr_find(&idrinfo->action_idr, index);
 266         spin_unlock(&idrinfo->lock);
 267
 268         return p;
 269 }
 270
 271 int tcf_idr_search(struct tc_action_net *tn, struct tc_action **a, u32 index)
 272 {
 273         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 274         struct tc_action *p = tcf_idr_lookup(index, idrinfo);
 275
 276         if (p) {
 277                 *a = p;
 278                 return 1;
 279         }
 280         return 0;
 281 }
 282 EXPORT_SYMBOL(tcf_idr_search);
 283
 284 bool tcf_idr_check(struct tc_action_net *tn, u32 index, struct tc_action **a,
 285                    int bind)
 286 {
 287         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 288         struct tc_action *p = tcf_idr_lookup(index, idrinfo);
 289
 290         if (index && p) {
 291                 if (bind)
 292                         p->tcfa_bindcnt++;
 293                 p->tcfa_refcnt++;
 294                 *a = p;
 295                 return true;
 296         }
 297         return false;
 298 }
 299 EXPORT_SYMBOL(tcf_idr_check);
 300
 301 int tcf_idr_create(struct tc_action_net *tn, u32 index, struct nlattr *est,
 302                    struct tc_action **a, const struct tc_action_ops *ops,
 303                    int bind, bool cpustats)
 304 {
 305         struct tc_action *p = kzalloc(ops->size, GFP_KERNEL);
 306         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 307         struct idr *idr = &idrinfo->action_idr;
 308         int err = -ENOMEM;
 309
 310         if (unlikely(!p))
 311                 return -ENOMEM;
 312         p->tcfa_refcnt = 1;
 313         if (bind)
 314                 p->tcfa_bindcnt = 1;
 315
 316         if (cpustats) {
 317                 p->cpu_bstats = netdev_alloc_pcpu_stats(struct gnet_stats_basic_cpu);
 318                 if (!p->cpu_bstats)
 319                         goto err1;
 320                 p->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
 321                 if (!p->cpu_qstats)
 322                         goto err2;
 323         }
 324         spin_lock_init(&p->tcfa_lock);
 325         idr_preload(GFP_KERNEL);
 326         spin_lock(&idrinfo->lock);
 327         /* user doesn't specify an index */
 328         if (!index) {
 329                 index = 1;
 330                 err = idr_alloc_u32(idr, NULL, &index, UINT_MAX, GFP_ATOMIC);
 331         } else {
 332                 err = idr_alloc_u32(idr, NULL, &index, index, GFP_ATOMIC);
 333         }
 334         spin_unlock(&idrinfo->lock);
 335         idr_preload_end();
 336         if (err)
 337                 goto err3;
 338
 339         p->tcfa_index = index;
 340         p->tcfa_tm.install = jiffies;
 341         p->tcfa_tm.lastuse = jiffies;
 342         p->tcfa_tm.firstuse = 0;
 343         if (est) {
 344                 err = gen_new_estimator(&p->tcfa_bstats, p->cpu_bstats,
 345                                         &p->tcfa_rate_est,
 346                                         &p->tcfa_lock, NULL, est);
 347                 if (err)
 348                         goto err4;
 349         }
 350
 351         p->idrinfo = idrinfo;
 352         p->ops = ops;
 353         INIT_LIST_HEAD(&p->list);
 354         *a = p;
 355         return 0;
 356 err4:
 357         idr_remove(idr, index);
 358 err3:
 359         free_percpu(p->cpu_qstats);
 360 err2:
 361         free_percpu(p->cpu_bstats);
 362 err1:
 363         kfree(p);
 364         return err;
 365 }
 366 EXPORT_SYMBOL(tcf_idr_create);
 367
 368 void tcf_idr_insert(struct tc_action_net *tn, struct tc_action *a)
 369 {
 370         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 371
 372         spin_lock(&idrinfo->lock);
 373         idr_replace(&idrinfo->action_idr, a, a->tcfa_index);
 374         spin_unlock(&idrinfo->lock);
 375 }
 376 EXPORT_SYMBOL(tcf_idr_insert);
 377
 378 void tcf_idrinfo_destroy(const struct tc_action_ops *ops,
 379                          struct tcf_idrinfo *idrinfo)
 380 {
 381         struct idr *idr = &idrinfo->action_idr;
 382         struct tc_action *p;
 383         int ret;
 384         unsigned long id = 1;
 385
 386         idr_for_each_entry_ul(idr, p, id) {
 387                 ret = __tcf_idr_release(p, false, true);
 388                 if (ret == ACT_P_DELETED)
 389                         module_put(ops->owner);
 390                 else if (ret < 0)
 391                         return;
 392         }
 393         idr_destroy(&idrinfo->action_idr);
 394 }
 395 EXPORT_SYMBOL(tcf_idrinfo_destroy);
 396
 397 static LIST_HEAD(act_base);
 398 static DEFINE_RWLOCK(act_mod_lock);
 399
 400 int tcf_register_action(struct tc_action_ops *act,
 401                         struct pernet_operations *ops)
 402 {
 403         struct tc_action_ops *a;
 404         int ret;
 405
 406         if (!act->act || !act->dump || !act->init || !act->walk || !act->lookup)
 407                 return -EINVAL;
 408
 409         /* We have to register pernet ops before making the action ops visible,
 410          * otherwise tcf_action_init_1() could get a partially initialized
 411          * netns.
 412          */
 413         ret = register_pernet_subsys(ops);
 414         if (ret)
 415                 return ret;
 416
 417         write_lock(&act_mod_lock);
 418         list_for_each_entry(a, &act_base, head) {
 419                 if (act->type == a->type || (strcmp(act->kind, a->kind) == 0)) {
 420                         write_unlock(&act_mod_lock);
 421                         unregister_pernet_subsys(ops);
 422                         return -EEXIST;
 423                 }
 424         }
 425         list_add_tail(&act->head, &act_base);
 426         write_unlock(&act_mod_lock);
 427
 428         return 0;
 429 }
 430 EXPORT_SYMBOL(tcf_register_action);
 431
 432 int tcf_unregister_action(struct tc_action_ops *act,
 433                           struct pernet_operations *ops)
 434 {
 435         struct tc_action_ops *a;
 436         int err = -ENOENT;
 437
 438         write_lock(&act_mod_lock);
 439         list_for_each_entry(a, &act_base, head) {
 440                 if (a == act) {
 441                         list_del(&act->head);
 442                         err = 0;
 443                         break;
 444                 }
 445         }
 446         write_unlock(&act_mod_lock);
 447         if (!err)
 448                 unregister_pernet_subsys(ops);
 449         return err;
 450 }
 451 EXPORT_SYMBOL(tcf_unregister_action);
 452
 453 /* lookup by name */
 454 static struct tc_action_ops *tc_lookup_action_n(char *kind)
 455 {
 456         struct tc_action_ops *a, *res = NULL;
 457
 458         if (kind) {
 459                 read_lock(&act_mod_lock);
 460                 list_for_each_entry(a, &act_base, head) {
 461                         if (strcmp(kind, a->kind) == 0) {
 462                                 if (try_module_get(a->owner))
 463                                         res = a;
 464                                 break;
 465                         }
 466                 }
 467                 read_unlock(&act_mod_lock);
 468         }
 469         return res;
 470 }
 471
 472 /* lookup by nlattr */
 473 static struct tc_action_ops *tc_lookup_action(struct nlattr *kind)
 474 {
 475         struct tc_action_ops *a, *res = NULL;
 476
 477         if (kind) {
 478                 read_lock(&act_mod_lock);
 479                 list_for_each_entry(a, &act_base, head) {
 480                         if (nla_strcmp(kind, a->kind) == 0) {
 481                                 if (try_module_get(a->owner))
 482                                         res = a;
 483                                 break;
 484                         }
 485                 }
 486                 read_unlock(&act_mod_lock);
 487         }
 488         return res;
 489 }
 490
 491 /*TCA_ACT_MAX_PRIO is 32, there count upto 32 */
 492 #define TCA_ACT_MAX_PRIO_MASK 0x1FF
 493 int tcf_action_exec(struct sk_buff *skb, struct tc_action **actions,
 494                     int nr_actions, struct tcf_result *res)
 495 {
 496         u32 jmp_prgcnt = 0;
 497         u32 jmp_ttl = TCA_ACT_MAX_PRIO; /*matches actions per filter */
 498         int i;
 499         int ret = TC_ACT_OK;
 500
 501         if (skb_skip_tc_classify(skb))
 502                 return TC_ACT_OK;
 503
 504 restart_act_graph:
 505         for (i = 0; i < nr_actions; i++) {
 506                 const struct tc_action *a = actions[i];
 507
 508                 if (jmp_prgcnt > 0) {
 509                         jmp_prgcnt -= 1;
 510                         continue;
 511                 }
 512 repeat:
 513                 ret = a->ops->act(skb, a, res);
 514                 if (ret == TC_ACT_REPEAT)
 515                         goto repeat;    /* we need a ttl - JHS */
 516
 517                 if (TC_ACT_EXT_CMP(ret, TC_ACT_JUMP)) {
 518                         jmp_prgcnt = ret & TCA_ACT_MAX_PRIO_MASK;
 519                         if (!jmp_prgcnt || (jmp_prgcnt > nr_actions)) {
 520                                 /* faulty opcode, stop pipeline */
 521                                 return TC_ACT_OK;
 522                         } else {
 523                                 jmp_ttl -= 1;
 524                                 if (jmp_ttl > 0)
 525                                         goto restart_act_graph;
 526                                 else /* faulty graph, stop pipeline */
 527                                         return TC_ACT_OK;
 528                         }
 529                 } else if (TC_ACT_EXT_CMP(ret, TC_ACT_GOTO_CHAIN)) {
 530                         tcf_action_goto_chain_exec(a, res);
 531                 }
 532
 533                 if (ret != TC_ACT_PIPE)
 534                         break;
 535         }
 536
 537         return ret;
 538 }
 539 EXPORT_SYMBOL(tcf_action_exec);
 540
 541 int tcf_action_destroy(struct list_head *actions, int bind)
 542 {
 543         const struct tc_action_ops *ops;
 544         struct tc_action *a, *tmp;
 545         int ret = 0;
 546
 547         list_for_each_entry_safe(a, tmp, actions, list) {
 548                 ops = a->ops;
 549                 ret = __tcf_idr_release(a, bind, true);
 550                 if (ret == ACT_P_DELETED)
 551                         module_put(ops->owner);
 552                 else if (ret < 0)
 553                         return ret;
 554         }
 555         return ret;
 556 }
 557
 558 int
 559 tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 560 {
 561         return a->ops->dump(skb, a, bind, ref);
 562 }
 563
 564 int
 565 tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 566 {
 567         int err = -EINVAL;
 568         unsigned char *b = skb_tail_pointer(skb);
 569         struct nlattr *nest;
 570
 571         if (nla_put_string(skb, TCA_KIND, a->ops->kind))
 572                 goto nla_put_failure;
 573         if (tcf_action_copy_stats(skb, a, 0))
 574                 goto nla_put_failure;
 575         if (a->act_cookie) {
 576                 if (nla_put(skb, TCA_ACT_COOKIE, a->act_cookie->len,
 577                             a->act_cookie->data))
 578                         goto nla_put_failure;
 579         }
 580
 581         nest = nla_nest_start(skb, TCA_OPTIONS);
 582         if (nest == NULL)
 583                 goto nla_put_failure;
 584         err = tcf_action_dump_old(skb, a, bind, ref);
 585         if (err > 0) {
 586                 nla_nest_end(skb, nest);
 587                 return err;
 588         }
 589
 590 nla_put_failure:
 591         nlmsg_trim(skb, b);
 592         return -1;
 593 }
 594 EXPORT_SYMBOL(tcf_action_dump_1);
 595
 596 int tcf_action_dump(struct sk_buff *skb, struct list_head *actions,
 597                     int bind, int ref)
 598 {
 599         struct tc_action *a;
 600         int err = -EINVAL;
 601         struct nlattr *nest;
 602
 603         list_for_each_entry(a, actions, list) {
 604                 nest = nla_nest_start(skb, a->order);
 605                 if (nest == NULL)
 606                         goto nla_put_failure;
 607                 err = tcf_action_dump_1(skb, a, bind, ref);
 608                 if (err < 0)
 609                         goto errout;
 610                 nla_nest_end(skb, nest);
 611         }
 612
 613         return 0;
 614
 615 nla_put_failure:
 616         err = -EINVAL;
 617 errout:
 618         nla_nest_cancel(skb, nest);
 619         return err;
 620 }
 621
 622 static struct tc_cookie *nla_memdup_cookie(struct nlattr **tb)
 623 {
 624         struct tc_cookie *c = kzalloc(sizeof(*c), GFP_KERNEL);
 625         if (!c)
 626                 return NULL;
 627
 628         c->data = nla_memdup(tb[TCA_ACT_COOKIE], GFP_KERNEL);
 629         if (!c->data) {
 630                 kfree(c);
 631                 return NULL;
 632         }
 633         c->len = nla_len(tb[TCA_ACT_COOKIE]);
 634
 635         return c;
 636 }
 637
 638 struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
 639                                     struct nlattr *nla, struct nlattr *est,
 640                                     char *name, int ovr, int bind,
 641                                     struct netlink_ext_ack *extack)
 642 {
 643         struct tc_action *a;
 644         struct tc_action_ops *a_o;
 645         struct tc_cookie *cookie = NULL;
 646         char act_name[IFNAMSIZ];
 647         struct nlattr *tb[TCA_ACT_MAX + 1];
 648         struct nlattr *kind;
 649         int err;
 650
 651         if (name == NULL) {
 652                 err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL, extack);
 653                 if (err < 0)
 654                         goto err_out;
 655                 err = -EINVAL;
 656                 kind = tb[TCA_ACT_KIND];
 657                 if (!kind) {
 658                         NL_SET_ERR_MSG(extack, "TC action kind must be specified");
 659                         goto err_out;
 660                 }
 661                 if (nla_strlcpy(act_name, kind, IFNAMSIZ) >= IFNAMSIZ) {
 662                         NL_SET_ERR_MSG(extack, "TC action name too long");
 663                         goto err_out;
 664                 }
 665                 if (tb[TCA_ACT_COOKIE]) {
 666                         int cklen = nla_len(tb[TCA_ACT_COOKIE]);
 667
 668                         if (cklen > TC_COOKIE_MAX_SIZE) {
 669                                 NL_SET_ERR_MSG(extack, "TC cookie size above the maximum");
 670                                 goto err_out;
 671                         }
 672
 673                         cookie = nla_memdup_cookie(tb);
 674                         if (!cookie) {
 675                                 NL_SET_ERR_MSG(extack, "No memory to generate TC cookie");
 676                                 err = -ENOMEM;
 677                                 goto err_out;
 678                         }
 679                 }
 680         } else {
 681                 if (strlcpy(act_name, name, IFNAMSIZ) >= IFNAMSIZ) {
 682                         NL_SET_ERR_MSG(extack, "TC action name too long");
 683                         err = -EINVAL;
 684                         goto err_out;
 685                 }
 686         }
 687
 688         a_o = tc_lookup_action_n(act_name);
 689         if (a_o == NULL) {
 690 #ifdef CONFIG_MODULES
 691                 rtnl_unlock();
 692                 request_module("act_%s", act_name);
 693                 rtnl_lock();
 694
 695                 a_o = tc_lookup_action_n(act_name);
 696
 697                 /* We dropped the RTNL semaphore in order to
 698                  * perform the module load.  So, even if we
 699                  * succeeded in loading the module we have to
 700                  * tell the caller to replay the request.  We
 701                  * indicate this using -EAGAIN.
 702                  */
 703                 if (a_o != NULL) {
 704                         err = -EAGAIN;
 705                         goto err_mod;
 706                 }
 707 #endif
 708                 NL_SET_ERR_MSG(extack, "Failed to load TC action module");
 709                 err = -ENOENT;
 710                 goto err_out;
 711         }
 712
 713         /* backward compatibility for policer */
 714         if (name == NULL)
 715                 err = a_o->init(net, tb[TCA_ACT_OPTIONS], est, &a, ovr, bind,
 716                                 extack);
 717         else
 718                 err = a_o->init(net, nla, est, &a, ovr, bind, extack);
 719         if (err < 0)
 720                 goto err_mod;
 721
 722         if (name == NULL && tb[TCA_ACT_COOKIE]) {
 723                 if (a->act_cookie) {
 724                         kfree(a->act_cookie->data);
 725                         kfree(a->act_cookie);
 726                 }
 727                 a->act_cookie = cookie;
 728         }
 729
 730         /* module count goes up only when brand new policy is created
 731          * if it exists and is only bound to in a_o->init() then
 732          * ACT_P_CREATED is not returned (a zero is).
 733          */
 734         if (err != ACT_P_CREATED)
 735                 module_put(a_o->owner);
 736
 737         if (TC_ACT_EXT_CMP(a->tcfa_action, TC_ACT_GOTO_CHAIN)) {
 738                 err = tcf_action_goto_chain_init(a, tp);
 739                 if (err) {
 740                         LIST_HEAD(actions);
 741
 742                         list_add_tail(&a->list, &actions);
 743                         tcf_action_destroy(&actions, bind);
 744                         NL_SET_ERR_MSG(extack, "Failed to init TC action chain");
 745                         return ERR_PTR(err);
 746                 }
 747         }
 748
 749         return a;
 750
 751 err_mod:
 752         module_put(a_o->owner);
 753 err_out:
 754         if (cookie) {
 755                 kfree(cookie->data);
 756                 kfree(cookie);
 757         }
 758         return ERR_PTR(err);
 759 }
 760
 761 static void cleanup_a(struct list_head *actions, int ovr)
 762 {
 763         struct tc_action *a;
 764
 765         if (!ovr)
 766                 return;
 767
 768         list_for_each_entry(a, actions, list)
 769                 a->tcfa_refcnt--;
 770 }
 771
 772 int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla,
 773                     struct nlattr *est, char *name, int ovr, int bind,
 774                     struct list_head *actions, size_t *attr_size,
 775                     struct netlink_ext_ack *extack)
 776 {
 777         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
 778         struct tc_action *act;
 779         size_t sz = 0;
 780         int err;
 781         int i;
 782
 783         err = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL, extack);
 784         if (err < 0)
 785                 return err;
 786
 787         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
 788                 act = tcf_action_init_1(net, tp, tb[i], est, name, ovr, bind,
 789                                         extack);
 790                 if (IS_ERR(act)) {
 791                         err = PTR_ERR(act);
 792                         goto err;
 793                 }
 794                 act->order = i;
 795                 sz += tcf_action_fill_size(act);
 796                 if (ovr)
 797                         act->tcfa_refcnt++;
 798                 list_add_tail(&act->list, actions);
 799         }
 800
 801         *attr_size = tcf_action_full_attrs_size(sz);
 802
 803         /* Remove the temp refcnt which was necessary to protect against
 804          * destroying an existing action which was being replaced
 805          */
 806         cleanup_a(actions, ovr);
 807         return 0;
 808
 809 err:
 810         tcf_action_destroy(actions, bind);
 811         return err;
 812 }
 813
 814 int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *p,
 815                           int compat_mode)
 816 {
 817         int err = 0;
 818         struct gnet_dump d;
 819
 820         if (p == NULL)
 821                 goto errout;
 822
 823         /* compat_mode being true specifies a call that is supposed
 824          * to add additional backward compatibility statistic TLVs.
 825          */
 826         if (compat_mode) {
 827                 if (p->type == TCA_OLD_COMPAT)
 828                         err = gnet_stats_start_copy_compat(skb, 0,
 829                                                            TCA_STATS,
 830                                                            TCA_XSTATS,
 831                                                            &p->tcfa_lock, &d,
 832                                                            TCA_PAD);
 833                 else
 834                         return 0;
 835         } else
 836                 err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
 837                                             &p->tcfa_lock, &d, TCA_ACT_PAD);
 838
 839         if (err < 0)
 840                 goto errout;
 841
 842         if (gnet_stats_copy_basic(NULL, &d, p->cpu_bstats, &p->tcfa_bstats) < 0 ||
 843             gnet_stats_copy_rate_est(&d, &p->tcfa_rate_est) < 0 ||
 844             gnet_stats_copy_queue(&d, p->cpu_qstats,
 845                                   &p->tcfa_qstats,
 846                                   p->tcfa_qstats.qlen) < 0)
 847                 goto errout;
 848
 849         if (gnet_stats_finish_copy(&d) < 0)
 850                 goto errout;
 851
 852         return 0;
 853
 854 errout:
 855         return -1;
 856 }
 857
 858 static int tca_get_fill(struct sk_buff *skb, struct list_head *actions,
 859                         u32 portid, u32 seq, u16 flags, int event, int bind,
 860                         int ref)
 861 {
 862         struct tcamsg *t;
 863         struct nlmsghdr *nlh;
 864         unsigned char *b = skb_tail_pointer(skb);
 865         struct nlattr *nest;
 866
 867         nlh = nlmsg_put(skb, portid, seq, event, sizeof(*t), flags);
 868         if (!nlh)
 869                 goto out_nlmsg_trim;
 870         t = nlmsg_data(nlh);
 871         t->tca_family = AF_UNSPEC;
 872         t->tca__pad1 = 0;
 873         t->tca__pad2 = 0;
 874
 875         nest = nla_nest_start(skb, TCA_ACT_TAB);
 876         if (!nest)
 877                 goto out_nlmsg_trim;
 878
 879         if (tcf_action_dump(skb, actions, bind, ref) < 0)
 880                 goto out_nlmsg_trim;
 881
 882         nla_nest_end(skb, nest);
 883
 884         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 885         return skb->len;
 886
 887 out_nlmsg_trim:
 888         nlmsg_trim(skb, b);
 889         return -1;
 890 }
 891
 892 static int
 893 tcf_get_notify(struct net *net, u32 portid, struct nlmsghdr *n,
 894                struct list_head *actions, int event,
 895                struct netlink_ext_ack *extack)
 896 {
 897         struct sk_buff *skb;
 898
 899         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 900         if (!skb)
 901                 return -ENOBUFS;
 902         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, event,
 903                          0, 0) <= 0) {
 904                 NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
 905                 kfree_skb(skb);
 906                 return -EINVAL;
 907         }
 908
 909         return rtnl_unicast(skb, net, portid);
 910 }
 911
 912 static struct tc_action *tcf_action_get_1(struct net *net, struct nlattr *nla,
 913                                           struct nlmsghdr *n, u32 portid,
 914                                           struct netlink_ext_ack *extack)
 915 {
 916         struct nlattr *tb[TCA_ACT_MAX + 1];
 917         const struct tc_action_ops *ops;
 918         struct tc_action *a;
 919         int index;
 920         int err;
 921
 922         err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL, extack);
 923         if (err < 0)
 924                 goto err_out;
 925
 926         err = -EINVAL;
 927         if (tb[TCA_ACT_INDEX] == NULL ||
 928             nla_len(tb[TCA_ACT_INDEX]) < sizeof(index)) {
 929                 NL_SET_ERR_MSG(extack, "Invalid TC action index value");
 930                 goto err_out;
 931         }
 932         index = nla_get_u32(tb[TCA_ACT_INDEX]);
 933
 934         err = -EINVAL;
 935         ops = tc_lookup_action(tb[TCA_ACT_KIND]);
 936         if (!ops) { /* could happen in batch of actions */
 937                 NL_SET_ERR_MSG(extack, "Specified TC action not found");
 938                 goto err_out;
 939         }
 940         err = -ENOENT;
 941         if (ops->lookup(net, &a, index, extack) == 0)
 942                 goto err_mod;
 943
 944         module_put(ops->owner);
 945         return a;
 946
 947 err_mod:
 948         module_put(ops->owner);
 949 err_out:
 950         return ERR_PTR(err);
 951 }
 952
 953 static int tca_action_flush(struct net *net, struct nlattr *nla,
 954                             struct nlmsghdr *n, u32 portid,
 955                             struct netlink_ext_ack *extack)
 956 {
 957         struct sk_buff *skb;
 958         unsigned char *b;
 959         struct nlmsghdr *nlh;
 960         struct tcamsg *t;
 961         struct netlink_callback dcb;
 962         struct nlattr *nest;
 963         struct nlattr *tb[TCA_ACT_MAX + 1];
 964         const struct tc_action_ops *ops;
 965         struct nlattr *kind;
 966         int err = -ENOMEM;
 967
 968         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 969         if (!skb)
 970                 return err;
 971
 972         b = skb_tail_pointer(skb);
 973
 974         err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL, extack);
 975         if (err < 0)
 976                 goto err_out;
 977
 978         err = -EINVAL;
 979         kind = tb[TCA_ACT_KIND];
 980         ops = tc_lookup_action(kind);
 981         if (!ops) { /*some idjot trying to flush unknown action */
 982                 NL_SET_ERR_MSG(extack, "Cannot flush unknown TC action");
 983                 goto err_out;
 984         }
 985
 986         nlh = nlmsg_put(skb, portid, n->nlmsg_seq, RTM_DELACTION,
 987                         sizeof(*t), 0);
 988         if (!nlh) {
 989                 NL_SET_ERR_MSG(extack, "Failed to create TC action flush notification");
 990                 goto out_module_put;
 991         }
 992         t = nlmsg_data(nlh);
 993         t->tca_family = AF_UNSPEC;
 994         t->tca__pad1 = 0;
 995         t->tca__pad2 = 0;
 996
 997         nest = nla_nest_start(skb, TCA_ACT_TAB);
 998         if (!nest) {
 999                 NL_SET_ERR_MSG(extack, "Failed to add new netlink message");
1000                 goto out_module_put;
1001         }
1002
1003         err = ops->walk(net, skb, &dcb, RTM_DELACTION, ops, extack);
1004         if (err <= 0) {
1005                 nla_nest_cancel(skb, nest);
1006                 goto out_module_put;
1007         }
1008
1009         nla_nest_end(skb, nest);
1010
1011         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1012         nlh->nlmsg_flags |= NLM_F_ROOT;
1013         module_put(ops->owner);
1014         err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1015                              n->nlmsg_flags & NLM_F_ECHO);
1016         if (err > 0)
1017                 return 0;
1018         if (err < 0)
1019                 NL_SET_ERR_MSG(extack, "Failed to send TC action flush notification");
1020
1021         return err;
1022
1023 out_module_put:
1024         module_put(ops->owner);
1025 err_out:
1026         kfree_skb(skb);
1027         return err;
1028 }
1029
1030 static int
1031 tcf_del_notify(struct net *net, struct nlmsghdr *n, struct list_head *actions,
1032                u32 portid, size_t attr_size, struct netlink_ext_ack *extack)
1033 {
1034         int ret;
1035         struct sk_buff *skb;
1036
1037         skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1038                         GFP_KERNEL);
1039         if (!skb)
1040                 return -ENOBUFS;
1041
1042         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, RTM_DELACTION,
1043                          0, 1) <= 0) {
1044                 NL_SET_ERR_MSG(extack, "Failed to fill netlink TC action attributes");
1045                 kfree_skb(skb);
1046                 return -EINVAL;
1047         }
1048
1049         /* now do the delete */
1050         ret = tcf_action_destroy(actions, 0);
1051         if (ret < 0) {
1052                 NL_SET_ERR_MSG(extack, "Failed to delete TC action");
1053                 kfree_skb(skb);
1054                 return ret;
1055         }
1056
1057         ret = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1058                              n->nlmsg_flags & NLM_F_ECHO);
1059         if (ret > 0)
1060                 return 0;
1061         return ret;
1062 }
1063
1064 static int
1065 tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
1066               u32 portid, int event, struct netlink_ext_ack *extack)
1067 {
1068         int i, ret;
1069         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1070         struct tc_action *act;
1071         size_t attr_size = 0;
1072         LIST_HEAD(actions);
1073
1074         ret = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL, extack);
1075         if (ret < 0)
1076                 return ret;
1077
1078         if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) {
1079                 if (tb[1])
1080                         return tca_action_flush(net, tb[1], n, portid, extack);
1081
1082                 NL_SET_ERR_MSG(extack, "Invalid netlink attributes while flushing TC action");
1083                 return -EINVAL;
1084         }
1085
1086         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1087                 act = tcf_action_get_1(net, tb[i], n, portid, extack);
1088                 if (IS_ERR(act)) {
1089                         ret = PTR_ERR(act);
1090                         goto err;
1091                 }
1092                 act->order = i;
1093                 attr_size += tcf_action_fill_size(act);
1094                 list_add_tail(&act->list, &actions);
1095         }
1096
1097         attr_size = tcf_action_full_attrs_size(attr_size);
1098
1099         if (event == RTM_GETACTION)
1100                 ret = tcf_get_notify(net, portid, n, &actions, event, extack);
1101         else { /* delete */
1102                 ret = tcf_del_notify(net, n, &actions, portid, attr_size, extack);
1103                 if (ret)
1104                         goto err;
1105                 return ret;
1106         }
1107 err:
1108         if (event != RTM_GETACTION)
1109                 tcf_action_destroy(&actions, 0);
1110         return ret;
1111 }
1112
1113 static int
1114 tcf_add_notify(struct net *net, struct nlmsghdr *n, struct list_head *actions,
1115                u32 portid, size_t attr_size, struct netlink_ext_ack *extack)
1116 {
1117         struct sk_buff *skb;
1118         int err = 0;
1119
1120         skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1121                         GFP_KERNEL);
1122         if (!skb)
1123                 return -ENOBUFS;
1124
1125         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, n->nlmsg_flags,
1126                          RTM_NEWACTION, 0, 0) <= 0) {
1127                 NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1128                 kfree_skb(skb);
1129                 return -EINVAL;
1130         }
1131
1132         err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1133                              n->nlmsg_flags & NLM_F_ECHO);
1134         if (err > 0)
1135                 err = 0;
1136         return err;
1137 }
1138
1139 static int tcf_action_add(struct net *net, struct nlattr *nla,
1140                           struct nlmsghdr *n, u32 portid, int ovr,
1141                           struct netlink_ext_ack *extack)
1142 {
1143         size_t attr_size = 0;
1144         int ret = 0;
1145         LIST_HEAD(actions);
1146
1147         ret = tcf_action_init(net, NULL, nla, NULL, NULL, ovr, 0, &actions,
1148                               &attr_size, extack);
1149         if (ret)
1150                 return ret;
1151
1152         return tcf_add_notify(net, n, &actions, portid, attr_size, extack);
1153 }
1154
1155 static u32 tcaa_root_flags_allowed = TCA_FLAG_LARGE_DUMP_ON;
1156 static const struct nla_policy tcaa_policy[TCA_ROOT_MAX + 1] = {
1157         [TCA_ROOT_FLAGS] = { .type = NLA_BITFIELD32,
1158                              .validation_data = &tcaa_root_flags_allowed },
1159         [TCA_ROOT_TIME_DELTA]      = { .type = NLA_U32 },
1160 };
1161
1162 static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n,
1163                          struct netlink_ext_ack *extack)
1164 {
1165         struct net *net = sock_net(skb->sk);
1166         struct nlattr *tca[TCA_ROOT_MAX + 1];
1167         u32 portid = skb ? NETLINK_CB(skb).portid : 0;
1168         int ret = 0, ovr = 0;
1169
1170         if ((n->nlmsg_type != RTM_GETACTION) &&
1171             !netlink_capable(skb, CAP_NET_ADMIN))
1172                 return -EPERM;
1173
1174         ret = nlmsg_parse(n, sizeof(struct tcamsg), tca, TCA_ROOT_MAX, NULL,
1175                           extack);
1176         if (ret < 0)
1177                 return ret;
1178
1179         if (tca[TCA_ACT_TAB] == NULL) {
1180                 NL_SET_ERR_MSG(extack, "Netlink action attributes missing");
1181                 return -EINVAL;
1182         }
1183
1184         /* n->nlmsg_flags & NLM_F_CREATE */
1185         switch (n->nlmsg_type) {
1186         case RTM_NEWACTION:
1187                 /* we are going to assume all other flags
1188                  * imply create only if it doesn't exist
1189                  * Note that CREATE | EXCL implies that
1190                  * but since we want avoid ambiguity (eg when flags
1191                  * is zero) then just set this
1192                  */
1193                 if (n->nlmsg_flags & NLM_F_REPLACE)
1194                         ovr = 1;
1195 replay:
1196                 ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, portid, ovr,
1197                                      extack);
1198                 if (ret == -EAGAIN)
1199                         goto replay;
1200                 break;
1201         case RTM_DELACTION:
1202                 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
1203                                     portid, RTM_DELACTION, extack);
1204                 break;
1205         case RTM_GETACTION:
1206                 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
1207                                     portid, RTM_GETACTION, extack);
1208                 break;
1209         default:
1210                 BUG();
1211         }
1212
1213         return ret;
1214 }
1215
1216 static struct nlattr *find_dump_kind(struct nlattr **nla)
1217 {
1218         struct nlattr *tb1, *tb2[TCA_ACT_MAX + 1];
1219         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1220         struct nlattr *kind;
1221
1222         tb1 = nla[TCA_ACT_TAB];
1223         if (tb1 == NULL)
1224                 return NULL;
1225
1226         if (nla_parse(tb, TCA_ACT_MAX_PRIO, nla_data(tb1),
1227                       NLMSG_ALIGN(nla_len(tb1)), NULL, NULL) < 0)
1228                 return NULL;
1229
1230         if (tb[1] == NULL)
1231                 return NULL;
1232         if (nla_parse_nested(tb2, TCA_ACT_MAX, tb[1], NULL, NULL) < 0)
1233                 return NULL;
1234         kind = tb2[TCA_ACT_KIND];
1235
1236         return kind;
1237 }
1238
1239 static int tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
1240 {
1241         struct net *net = sock_net(skb->sk);
1242         struct nlmsghdr *nlh;
1243         unsigned char *b = skb_tail_pointer(skb);
1244         struct nlattr *nest;
1245         struct tc_action_ops *a_o;
1246         int ret = 0;
1247         struct tcamsg *t = (struct tcamsg *) nlmsg_data(cb->nlh);
1248         struct nlattr *tb[TCA_ROOT_MAX + 1];
1249         struct nlattr *count_attr = NULL;
1250         unsigned long jiffy_since = 0;
1251         struct nlattr *kind = NULL;
1252         struct nla_bitfield32 bf;
1253         u32 msecs_since = 0;
1254         u32 act_count = 0;
1255
1256         ret = nlmsg_parse(cb->nlh, sizeof(struct tcamsg), tb, TCA_ROOT_MAX,
1257                           tcaa_policy, NULL);
1258         if (ret < 0)
1259                 return ret;
1260
1261         kind = find_dump_kind(tb);
1262         if (kind == NULL) {
1263                 pr_info("tc_dump_action: action bad kind\n");
1264                 return 0;
1265         }
1266
1267         a_o = tc_lookup_action(kind);
1268         if (a_o == NULL)
1269                 return 0;
1270
1271         cb->args[2] = 0;
1272         if (tb[TCA_ROOT_FLAGS]) {
1273                 bf = nla_get_bitfield32(tb[TCA_ROOT_FLAGS]);
1274                 cb->args[2] = bf.value;
1275         }
1276
1277         if (tb[TCA_ROOT_TIME_DELTA]) {
1278                 msecs_since = nla_get_u32(tb[TCA_ROOT_TIME_DELTA]);
1279         }
1280
1281         nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
1282                         cb->nlh->nlmsg_type, sizeof(*t), 0);
1283         if (!nlh)
1284                 goto out_module_put;
1285
1286         if (msecs_since)
1287                 jiffy_since = jiffies - msecs_to_jiffies(msecs_since);
1288
1289         t = nlmsg_data(nlh);
1290         t->tca_family = AF_UNSPEC;
1291         t->tca__pad1 = 0;
1292         t->tca__pad2 = 0;
1293         cb->args[3] = jiffy_since;
1294         count_attr = nla_reserve(skb, TCA_ROOT_COUNT, sizeof(u32));
1295         if (!count_attr)
1296                 goto out_module_put;
1297
1298         nest = nla_nest_start(skb, TCA_ACT_TAB);
1299         if (nest == NULL)
1300                 goto out_module_put;
1301
1302         ret = a_o->walk(net, skb, cb, RTM_GETACTION, a_o, NULL);
1303         if (ret < 0)
1304                 goto out_module_put;
1305
1306         if (ret > 0) {
1307                 nla_nest_end(skb, nest);
1308                 ret = skb->len;
1309                 act_count = cb->args[1];
1310                 memcpy(nla_data(count_attr), &act_count, sizeof(u32));
1311                 cb->args[1] = 0;
1312         } else
1313                 nlmsg_trim(skb, b);
1314
1315         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1316         if (NETLINK_CB(cb->skb).portid && ret)
1317                 nlh->nlmsg_flags |= NLM_F_MULTI;
1318         module_put(a_o->owner);
1319         return skb->len;
1320
1321 out_module_put:
1322         module_put(a_o->owner);
1323         nlmsg_trim(skb, b);
1324         return skb->len;
1325 }
1326
1327 struct tcf_action_net {
1328         struct rhashtable egdev_ht;
1329 };
1330
1331 static unsigned int tcf_action_net_id;
1332
1333 struct tcf_action_egdev_cb {
1334         struct list_head list;
1335         tc_setup_cb_t *cb;
1336         void *cb_priv;
1337 };
1338
1339 struct tcf_action_egdev {
1340         struct rhash_head ht_node;
1341         const struct net_device *dev;
1342         unsigned int refcnt;
1343         struct list_head cb_list;
1344 };
1345
1346 static const struct rhashtable_params tcf_action_egdev_ht_params = {
1347         .key_offset = offsetof(struct tcf_action_egdev, dev),
1348         .head_offset = offsetof(struct tcf_action_egdev, ht_node),
1349         .key_len = sizeof(const struct net_device *),
1350 };
1351
1352 static struct tcf_action_egdev *
1353 tcf_action_egdev_lookup(const struct net_device *dev)
1354 {
1355         struct net *net = dev_net(dev);
1356         struct tcf_action_net *tan = net_generic(net, tcf_action_net_id);
1357
1358         return rhashtable_lookup_fast(&tan->egdev_ht, &dev,
1359                                       tcf_action_egdev_ht_params);
1360 }
1361
1362 static struct tcf_action_egdev *
1363 tcf_action_egdev_get(const struct net_device *dev)
1364 {
1365         struct tcf_action_egdev *egdev;
1366         struct tcf_action_net *tan;
1367
1368         egdev = tcf_action_egdev_lookup(dev);
1369         if (egdev)
1370                 goto inc_ref;
1371
1372         egdev = kzalloc(sizeof(*egdev), GFP_KERNEL);
1373         if (!egdev)
1374                 return NULL;
1375         INIT_LIST_HEAD(&egdev->cb_list);
1376         egdev->dev = dev;
1377         tan = net_generic(dev_net(dev), tcf_action_net_id);
1378         rhashtable_insert_fast(&tan->egdev_ht, &egdev->ht_node,
1379                                tcf_action_egdev_ht_params);
1380
1381 inc_ref:
1382         egdev->refcnt++;
1383         return egdev;
1384 }
1385
1386 static void tcf_action_egdev_put(struct tcf_action_egdev *egdev)
1387 {
1388         struct tcf_action_net *tan;
1389
1390         if (--egdev->refcnt)
1391                 return;
1392         tan = net_generic(dev_net(egdev->dev), tcf_action_net_id);
1393         rhashtable_remove_fast(&tan->egdev_ht, &egdev->ht_node,
1394                                tcf_action_egdev_ht_params);
1395         kfree(egdev);
1396 }
1397
1398 static struct tcf_action_egdev_cb *
1399 tcf_action_egdev_cb_lookup(struct tcf_action_egdev *egdev,
1400                            tc_setup_cb_t *cb, void *cb_priv)
1401 {
1402         struct tcf_action_egdev_cb *egdev_cb;
1403
1404         list_for_each_entry(egdev_cb, &egdev->cb_list, list)
1405                 if (egdev_cb->cb == cb && egdev_cb->cb_priv == cb_priv)
1406                         return egdev_cb;
1407         return NULL;
1408 }
1409
1410 static int tcf_action_egdev_cb_call(struct tcf_action_egdev *egdev,
1411                                     enum tc_setup_type type,
1412                                     void *type_data, bool err_stop)
1413 {
1414         struct tcf_action_egdev_cb *egdev_cb;
1415         int ok_count = 0;
1416         int err;
1417
1418         list_for_each_entry(egdev_cb, &egdev->cb_list, list) {
1419                 err = egdev_cb->cb(type, type_data, egdev_cb->cb_priv);
1420                 if (err) {
1421                         if (err_stop)
1422                                 return err;
1423                 } else {
1424                         ok_count++;
1425                 }
1426         }
1427         return ok_count;
1428 }
1429
1430 static int tcf_action_egdev_cb_add(struct tcf_action_egdev *egdev,
1431                                    tc_setup_cb_t *cb, void *cb_priv)
1432 {
1433         struct tcf_action_egdev_cb *egdev_cb;
1434
1435         egdev_cb = tcf_action_egdev_cb_lookup(egdev, cb, cb_priv);
1436         if (WARN_ON(egdev_cb))
1437                 return -EEXIST;
1438         egdev_cb = kzalloc(sizeof(*egdev_cb), GFP_KERNEL);
1439         if (!egdev_cb)
1440                 return -ENOMEM;
1441         egdev_cb->cb = cb;
1442         egdev_cb->cb_priv = cb_priv;
1443         list_add(&egdev_cb->list, &egdev->cb_list);
1444         return 0;
1445 }
1446
1447 static void tcf_action_egdev_cb_del(struct tcf_action_egdev *egdev,
1448                                     tc_setup_cb_t *cb, void *cb_priv)
1449 {
1450         struct tcf_action_egdev_cb *egdev_cb;
1451
1452         egdev_cb = tcf_action_egdev_cb_lookup(egdev, cb, cb_priv);
1453         if (WARN_ON(!egdev_cb))
1454                 return;
1455         list_del(&egdev_cb->list);
1456         kfree(egdev_cb);
1457 }
1458
1459 static int __tc_setup_cb_egdev_register(const struct net_device *dev,
1460                                         tc_setup_cb_t *cb, void *cb_priv)
1461 {
1462         struct tcf_action_egdev *egdev = tcf_action_egdev_get(dev);
1463         int err;
1464
1465         if (!egdev)
1466                 return -ENOMEM;
1467         err = tcf_action_egdev_cb_add(egdev, cb, cb_priv);
1468         if (err)
1469                 goto err_cb_add;
1470         return 0;
1471
1472 err_cb_add:
1473         tcf_action_egdev_put(egdev);
1474         return err;
1475 }
1476 int tc_setup_cb_egdev_register(const struct net_device *dev,
1477                                tc_setup_cb_t *cb, void *cb_priv)
1478 {
1479         int err;
1480
1481         rtnl_lock();
1482         err = __tc_setup_cb_egdev_register(dev, cb, cb_priv);
1483         rtnl_unlock();
1484         return err;
1485 }
1486 EXPORT_SYMBOL_GPL(tc_setup_cb_egdev_register);
1487
1488 static void __tc_setup_cb_egdev_unregister(const struct net_device *dev,
1489                                            tc_setup_cb_t *cb, void *cb_priv)
1490 {
1491         struct tcf_action_egdev *egdev = tcf_action_egdev_lookup(dev);
1492
1493         if (WARN_ON(!egdev))
1494                 return;
1495         tcf_action_egdev_cb_del(egdev, cb, cb_priv);
1496         tcf_action_egdev_put(egdev);
1497 }
1498 void tc_setup_cb_egdev_unregister(const struct net_device *dev,
1499                                   tc_setup_cb_t *cb, void *cb_priv)
1500 {
1501         rtnl_lock();
1502         __tc_setup_cb_egdev_unregister(dev, cb, cb_priv);
1503         rtnl_unlock();
1504 }
1505 EXPORT_SYMBOL_GPL(tc_setup_cb_egdev_unregister);
1506
1507 int tc_setup_cb_egdev_call(const struct net_device *dev,
1508                            enum tc_setup_type type, void *type_data,
1509                            bool err_stop)
1510 {
1511         struct tcf_action_egdev *egdev = tcf_action_egdev_lookup(dev);
1512
1513         if (!egdev)
1514                 return 0;
1515         return tcf_action_egdev_cb_call(egdev, type, type_data, err_stop);
1516 }
1517 EXPORT_SYMBOL_GPL(tc_setup_cb_egdev_call);
1518
1519 static __net_init int tcf_action_net_init(struct net *net)
1520 {
1521         struct tcf_action_net *tan = net_generic(net, tcf_action_net_id);
1522
1523         return rhashtable_init(&tan->egdev_ht, &tcf_action_egdev_ht_params);
1524 }
1525
1526 static void __net_exit tcf_action_net_exit(struct net *net)
1527 {
1528         struct tcf_action_net *tan = net_generic(net, tcf_action_net_id);
1529
1530         rhashtable_destroy(&tan->egdev_ht);
1531 }
1532
1533 static struct pernet_operations tcf_action_net_ops = {
1534         .init = tcf_action_net_init,
1535         .exit = tcf_action_net_exit,
1536         .id = &tcf_action_net_id,
1537         .size = sizeof(struct tcf_action_net),
1538 };
1539
1540 static int __init tc_action_init(void)
1541 {
1542         int err;
1543
1544         err = register_pernet_subsys(&tcf_action_net_ops);
1545         if (err)
1546                 return err;
1547
1548         rtnl_register(PF_UNSPEC, RTM_NEWACTION, tc_ctl_action, NULL, 0);
1549         rtnl_register(PF_UNSPEC, RTM_DELACTION, tc_ctl_action, NULL, 0);
1550         rtnl_register(PF_UNSPEC, RTM_GETACTION, tc_ctl_action, tc_dump_action,
1551                       0);
1552
1553         return 0;
1554 }
1555
1556 subsys_initcall(tc_action_init);