1 /* 2 * Copyright (C) 2017-2018 Netronome Systems, Inc. 3 * 4 * This software is licensed under the GNU General License Version 2, 5 * June 1991 as shown in the file COPYING in the top-level directory of this 6 * source tree. 7 * 8 * THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" 9 * WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, 10 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 11 * FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE 12 * OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME 13 * THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION. 14 */ 15 16 #include <linux/bpf.h> 17 #include <linux/bpf_verifier.h> 18 #include <linux/bug.h> 19 #include <linux/kdev_t.h> 20 #include <linux/list.h> 21 #include <linux/lockdep.h> 22 #include <linux/netdevice.h> 23 #include <linux/printk.h> 24 #include <linux/proc_ns.h> 25 #include <linux/rhashtable.h> 26 #include <linux/rtnetlink.h> 27 #include <linux/rwsem.h> 28 #include <net/netdev_lock.h> 29 #include <net/xdp.h> 30 31 /* Protects offdevs, members of bpf_offload_netdev and offload members 32 * of all progs. 33 * RTNL lock cannot be taken when holding this lock. 34 */ 35 static DECLARE_RWSEM(bpf_devs_lock); 36 37 struct bpf_offload_dev { 38 const struct bpf_prog_offload_ops *ops; 39 struct list_head netdevs; 40 void *priv; 41 }; 42 43 struct bpf_offload_netdev { 44 struct rhash_head l; 45 struct net_device *netdev; 46 struct bpf_offload_dev *offdev; /* NULL when bound-only */ 47 struct list_head progs; 48 struct list_head maps; 49 struct list_head offdev_netdevs; 50 }; 51 52 static const struct rhashtable_params offdevs_params = { 53 .nelem_hint = 4, 54 .key_len = sizeof(struct net_device *), 55 .key_offset = offsetof(struct bpf_offload_netdev, netdev), 56 .head_offset = offsetof(struct bpf_offload_netdev, l), 57 .automatic_shrinking = true, 58 }; 59 60 static struct rhashtable offdevs; 61 62 static int bpf_dev_offload_check(struct net_device *netdev) 63 { 64 if (!netdev) 65 return -EINVAL; 66 if (!netdev->netdev_ops->ndo_bpf) 67 return -EOPNOTSUPP; 68 return 0; 69 } 70 71 static struct bpf_offload_netdev * 72 bpf_offload_find_netdev(struct net_device *netdev) 73 { 74 lockdep_assert_held(&bpf_devs_lock); 75 76 return rhashtable_lookup_fast(&offdevs, &netdev, offdevs_params); 77 } 78 79 static int __bpf_offload_dev_netdev_register(struct bpf_offload_dev *offdev, 80 struct net_device *netdev) 81 { 82 struct bpf_offload_netdev *ondev; 83 int err; 84 85 ondev = kzalloc(sizeof(*ondev), GFP_KERNEL); 86 if (!ondev) 87 return -ENOMEM; 88 89 ondev->netdev = netdev; 90 ondev->offdev = offdev; 91 INIT_LIST_HEAD(&ondev->progs); 92 INIT_LIST_HEAD(&ondev->maps); 93 94 err = rhashtable_insert_fast(&offdevs, &ondev->l, offdevs_params); 95 if (err) { 96 netdev_warn(netdev, "failed to register for BPF offload\n"); 97 goto err_free; 98 } 99 100 if (offdev) 101 list_add(&ondev->offdev_netdevs, &offdev->netdevs); 102 return 0; 103 104 err_free: 105 kfree(ondev); 106 return err; 107 } 108 109 static void __bpf_prog_offload_destroy(struct bpf_prog *prog) 110 { 111 struct bpf_prog_offload *offload = prog->aux->offload; 112 113 if (offload->dev_state) 114 offload->offdev->ops->destroy(prog); 115 116 list_del_init(&offload->offloads); 117 kfree(offload); 118 prog->aux->offload = NULL; 119 } 120 121 static int bpf_map_offload_ndo(struct bpf_offloaded_map *offmap, 122 enum bpf_netdev_command cmd) 123 { 124 struct netdev_bpf data = {}; 125 struct net_device *netdev; 126 127 ASSERT_RTNL(); 128 129 data.command = cmd; 130 data.offmap = offmap; 131 /* Caller must make sure netdev is valid */ 132 netdev = offmap->netdev; 133 134 return netdev->netdev_ops->ndo_bpf(netdev, &data); 135 } 136 137 static void __bpf_map_offload_destroy(struct bpf_offloaded_map *offmap) 138 { 139 WARN_ON(bpf_map_offload_ndo(offmap, BPF_OFFLOAD_MAP_FREE)); 140 /* Make sure BPF_MAP_GET_NEXT_ID can't find this dead map */ 141 bpf_map_free_id(&offmap->map); 142 list_del_init(&offmap->offloads); 143 offmap->netdev = NULL; 144 } 145 146 static void __bpf_offload_dev_netdev_unregister(struct bpf_offload_dev *offdev, 147 struct net_device *netdev) 148 { 149 struct bpf_offload_netdev *ondev, *altdev = NULL; 150 struct bpf_offloaded_map *offmap, *mtmp; 151 struct bpf_prog_offload *offload, *ptmp; 152 153 ASSERT_RTNL(); 154 155 ondev = rhashtable_lookup_fast(&offdevs, &netdev, offdevs_params); 156 if (WARN_ON(!ondev)) 157 return; 158 159 WARN_ON(rhashtable_remove_fast(&offdevs, &ondev->l, offdevs_params)); 160 161 /* Try to move the objects to another netdev of the device */ 162 if (offdev) { 163 list_del(&ondev->offdev_netdevs); 164 altdev = list_first_entry_or_null(&offdev->netdevs, 165 struct bpf_offload_netdev, 166 offdev_netdevs); 167 } 168 169 if (altdev) { 170 list_for_each_entry(offload, &ondev->progs, offloads) 171 offload->netdev = altdev->netdev; 172 list_splice_init(&ondev->progs, &altdev->progs); 173 174 list_for_each_entry(offmap, &ondev->maps, offloads) 175 offmap->netdev = altdev->netdev; 176 list_splice_init(&ondev->maps, &altdev->maps); 177 } else { 178 list_for_each_entry_safe(offload, ptmp, &ondev->progs, offloads) 179 __bpf_prog_offload_destroy(offload->prog); 180 list_for_each_entry_safe(offmap, mtmp, &ondev->maps, offloads) 181 __bpf_map_offload_destroy(offmap); 182 } 183 184 WARN_ON(!list_empty(&ondev->progs)); 185 WARN_ON(!list_empty(&ondev->maps)); 186 kfree(ondev); 187 } 188 189 static int __bpf_prog_dev_bound_init(struct bpf_prog *prog, struct net_device *netdev) 190 { 191 struct bpf_offload_netdev *ondev; 192 struct bpf_prog_offload *offload; 193 int err; 194 195 offload = kzalloc(sizeof(*offload), GFP_USER); 196 if (!offload) 197 return -ENOMEM; 198 199 offload->prog = prog; 200 offload->netdev = netdev; 201 202 ondev = bpf_offload_find_netdev(offload->netdev); 203 /* When program is offloaded require presence of "true" 204 * bpf_offload_netdev, avoid the one created for !ondev case below. 205 */ 206 if (bpf_prog_is_offloaded(prog->aux) && (!ondev || !ondev->offdev)) { 207 err = -EINVAL; 208 goto err_free; 209 } 210 if (!ondev) { 211 /* When only binding to the device, explicitly 212 * create an entry in the hashtable. 213 */ 214 err = __bpf_offload_dev_netdev_register(NULL, offload->netdev); 215 if (err) 216 goto err_free; 217 ondev = bpf_offload_find_netdev(offload->netdev); 218 } 219 offload->offdev = ondev->offdev; 220 prog->aux->offload = offload; 221 list_add_tail(&offload->offloads, &ondev->progs); 222 223 return 0; 224 err_free: 225 kfree(offload); 226 return err; 227 } 228 229 int bpf_prog_dev_bound_init(struct bpf_prog *prog, union bpf_attr *attr) 230 { 231 struct net_device *netdev; 232 int err; 233 234 if (attr->prog_type != BPF_PROG_TYPE_SCHED_CLS && 235 attr->prog_type != BPF_PROG_TYPE_XDP) 236 return -EINVAL; 237 238 if (attr->prog_flags & ~(BPF_F_XDP_DEV_BOUND_ONLY | BPF_F_XDP_HAS_FRAGS)) 239 return -EINVAL; 240 241 /* Frags are allowed only if program is dev-bound-only, but not 242 * if it is requesting bpf offload. 243 */ 244 if (attr->prog_flags & BPF_F_XDP_HAS_FRAGS && 245 !(attr->prog_flags & BPF_F_XDP_DEV_BOUND_ONLY)) 246 return -EINVAL; 247 248 if (attr->prog_type == BPF_PROG_TYPE_SCHED_CLS && 249 attr->prog_flags & BPF_F_XDP_DEV_BOUND_ONLY) 250 return -EINVAL; 251 252 netdev = dev_get_by_index(current->nsproxy->net_ns, attr->prog_ifindex); 253 if (!netdev) 254 return -EINVAL; 255 256 err = bpf_dev_offload_check(netdev); 257 if (err) 258 goto out; 259 260 prog->aux->offload_requested = !(attr->prog_flags & BPF_F_XDP_DEV_BOUND_ONLY); 261 262 down_write(&bpf_devs_lock); 263 err = __bpf_prog_dev_bound_init(prog, netdev); 264 up_write(&bpf_devs_lock); 265 266 out: 267 dev_put(netdev); 268 return err; 269 } 270 271 int bpf_prog_dev_bound_inherit(struct bpf_prog *new_prog, struct bpf_prog *old_prog) 272 { 273 int err; 274 275 if (!bpf_prog_is_dev_bound(old_prog->aux)) 276 return 0; 277 278 if (bpf_prog_is_offloaded(old_prog->aux)) 279 return -EINVAL; 280 281 new_prog->aux->dev_bound = old_prog->aux->dev_bound; 282 new_prog->aux->offload_requested = old_prog->aux->offload_requested; 283 284 down_write(&bpf_devs_lock); 285 if (!old_prog->aux->offload) { 286 err = -EINVAL; 287 goto out; 288 } 289 290 err = __bpf_prog_dev_bound_init(new_prog, old_prog->aux->offload->netdev); 291 292 out: 293 up_write(&bpf_devs_lock); 294 return err; 295 } 296 297 int bpf_prog_offload_verifier_prep(struct bpf_prog *prog) 298 { 299 struct bpf_prog_offload *offload; 300 int ret = -ENODEV; 301 302 down_read(&bpf_devs_lock); 303 offload = prog->aux->offload; 304 if (offload) { 305 ret = offload->offdev->ops->prepare(prog); 306 offload->dev_state = !ret; 307 } 308 up_read(&bpf_devs_lock); 309 310 return ret; 311 } 312 313 int bpf_prog_offload_verify_insn(struct bpf_verifier_env *env, 314 int insn_idx, int prev_insn_idx) 315 { 316 struct bpf_prog_offload *offload; 317 int ret = -ENODEV; 318 319 down_read(&bpf_devs_lock); 320 offload = env->prog->aux->offload; 321 if (offload) 322 ret = offload->offdev->ops->insn_hook(env, insn_idx, 323 prev_insn_idx); 324 up_read(&bpf_devs_lock); 325 326 return ret; 327 } 328 329 int bpf_prog_offload_finalize(struct bpf_verifier_env *env) 330 { 331 struct bpf_prog_offload *offload; 332 int ret = -ENODEV; 333 334 down_read(&bpf_devs_lock); 335 offload = env->prog->aux->offload; 336 if (offload) { 337 if (offload->offdev->ops->finalize) 338 ret = offload->offdev->ops->finalize(env); 339 else 340 ret = 0; 341 } 342 up_read(&bpf_devs_lock); 343 344 return ret; 345 } 346 347 void 348 bpf_prog_offload_replace_insn(struct bpf_verifier_env *env, u32 off, 349 struct bpf_insn *insn) 350 { 351 const struct bpf_prog_offload_ops *ops; 352 struct bpf_prog_offload *offload; 353 int ret = -EOPNOTSUPP; 354 355 down_read(&bpf_devs_lock); 356 offload = env->prog->aux->offload; 357 if (offload) { 358 ops = offload->offdev->ops; 359 if (!offload->opt_failed && ops->replace_insn) 360 ret = ops->replace_insn(env, off, insn); 361 offload->opt_failed |= ret; 362 } 363 up_read(&bpf_devs_lock); 364 } 365 366 void 367 bpf_prog_offload_remove_insns(struct bpf_verifier_env *env, u32 off, u32 cnt) 368 { 369 struct bpf_prog_offload *offload; 370 int ret = -EOPNOTSUPP; 371 372 down_read(&bpf_devs_lock); 373 offload = env->prog->aux->offload; 374 if (offload) { 375 if (!offload->opt_failed && offload->offdev->ops->remove_insns) 376 ret = offload->offdev->ops->remove_insns(env, off, cnt); 377 offload->opt_failed |= ret; 378 } 379 up_read(&bpf_devs_lock); 380 } 381 382 void bpf_prog_dev_bound_destroy(struct bpf_prog *prog) 383 { 384 struct bpf_offload_netdev *ondev; 385 struct net_device *netdev; 386 387 rtnl_lock(); 388 down_write(&bpf_devs_lock); 389 if (prog->aux->offload) { 390 list_del_init(&prog->aux->offload->offloads); 391 392 netdev = prog->aux->offload->netdev; 393 __bpf_prog_offload_destroy(prog); 394 395 ondev = bpf_offload_find_netdev(netdev); 396 if (!ondev->offdev && list_empty(&ondev->progs)) 397 __bpf_offload_dev_netdev_unregister(NULL, netdev); 398 } 399 up_write(&bpf_devs_lock); 400 rtnl_unlock(); 401 } 402 403 static int bpf_prog_offload_translate(struct bpf_prog *prog) 404 { 405 struct bpf_prog_offload *offload; 406 int ret = -ENODEV; 407 408 down_read(&bpf_devs_lock); 409 offload = prog->aux->offload; 410 if (offload) 411 ret = offload->offdev->ops->translate(prog); 412 up_read(&bpf_devs_lock); 413 414 return ret; 415 } 416 417 static unsigned int bpf_prog_warn_on_exec(const void *ctx, 418 const struct bpf_insn *insn) 419 { 420 WARN(1, "attempt to execute device eBPF program on the host!"); 421 return 0; 422 } 423 424 int bpf_prog_offload_compile(struct bpf_prog *prog) 425 { 426 prog->bpf_func = bpf_prog_warn_on_exec; 427 428 return bpf_prog_offload_translate(prog); 429 } 430 431 struct ns_get_path_bpf_prog_args { 432 struct bpf_prog *prog; 433 struct bpf_prog_info *info; 434 }; 435 436 static struct ns_common *bpf_prog_offload_info_fill_ns(void *private_data) 437 { 438 struct ns_get_path_bpf_prog_args *args = private_data; 439 struct bpf_prog_aux *aux = args->prog->aux; 440 struct ns_common *ns; 441 struct net *net; 442 443 rtnl_lock(); 444 down_read(&bpf_devs_lock); 445 446 if (aux->offload) { 447 args->info->ifindex = aux->offload->netdev->ifindex; 448 net = dev_net(aux->offload->netdev); 449 get_net(net); 450 ns = &net->ns; 451 } else { 452 args->info->ifindex = 0; 453 ns = NULL; 454 } 455 456 up_read(&bpf_devs_lock); 457 rtnl_unlock(); 458 459 return ns; 460 } 461 462 int bpf_prog_offload_info_fill(struct bpf_prog_info *info, 463 struct bpf_prog *prog) 464 { 465 struct ns_get_path_bpf_prog_args args = { 466 .prog = prog, 467 .info = info, 468 }; 469 struct bpf_prog_aux *aux = prog->aux; 470 struct inode *ns_inode; 471 struct path ns_path; 472 char __user *uinsns; 473 int res; 474 u32 ulen; 475 476 res = ns_get_path_cb(&ns_path, bpf_prog_offload_info_fill_ns, &args); 477 if (res) { 478 if (!info->ifindex) 479 return -ENODEV; 480 return res; 481 } 482 483 down_read(&bpf_devs_lock); 484 485 if (!aux->offload) { 486 up_read(&bpf_devs_lock); 487 return -ENODEV; 488 } 489 490 ulen = info->jited_prog_len; 491 info->jited_prog_len = aux->offload->jited_len; 492 if (info->jited_prog_len && ulen) { 493 uinsns = u64_to_user_ptr(info->jited_prog_insns); 494 ulen = min_t(u32, info->jited_prog_len, ulen); 495 if (copy_to_user(uinsns, aux->offload->jited_image, ulen)) { 496 up_read(&bpf_devs_lock); 497 return -EFAULT; 498 } 499 } 500 501 up_read(&bpf_devs_lock); 502 503 ns_inode = ns_path.dentry->d_inode; 504 info->netns_dev = new_encode_dev(ns_inode->i_sb->s_dev); 505 info->netns_ino = ns_inode->i_ino; 506 path_put(&ns_path); 507 508 return 0; 509 } 510 511 const struct bpf_prog_ops bpf_offload_prog_ops = { 512 }; 513 514 struct bpf_map *bpf_map_offload_map_alloc(union bpf_attr *attr) 515 { 516 struct net *net = current->nsproxy->net_ns; 517 struct bpf_offload_netdev *ondev; 518 struct bpf_offloaded_map *offmap; 519 int err; 520 521 if (!capable(CAP_SYS_ADMIN)) 522 return ERR_PTR(-EPERM); 523 if (attr->map_type != BPF_MAP_TYPE_ARRAY && 524 attr->map_type != BPF_MAP_TYPE_HASH) 525 return ERR_PTR(-EINVAL); 526 527 offmap = bpf_map_area_alloc(sizeof(*offmap), NUMA_NO_NODE); 528 if (!offmap) 529 return ERR_PTR(-ENOMEM); 530 531 bpf_map_init_from_attr(&offmap->map, attr); 532 rtnl_lock(); 533 offmap->netdev = __dev_get_by_index(net, attr->map_ifindex); 534 err = bpf_dev_offload_check(offmap->netdev); 535 if (err) 536 goto err_unlock_rtnl; 537 538 netdev_lock_ops(offmap->netdev); 539 down_write(&bpf_devs_lock); 540 541 ondev = bpf_offload_find_netdev(offmap->netdev); 542 if (!ondev) { 543 err = -EINVAL; 544 goto err_unlock; 545 } 546 547 err = bpf_map_offload_ndo(offmap, BPF_OFFLOAD_MAP_ALLOC); 548 if (err) 549 goto err_unlock; 550 551 list_add_tail(&offmap->offloads, &ondev->maps); 552 up_write(&bpf_devs_lock); 553 netdev_unlock_ops(offmap->netdev); 554 rtnl_unlock(); 555 556 return &offmap->map; 557 558 err_unlock: 559 up_write(&bpf_devs_lock); 560 netdev_unlock_ops(offmap->netdev); 561 err_unlock_rtnl: 562 rtnl_unlock(); 563 bpf_map_area_free(offmap); 564 return ERR_PTR(err); 565 } 566 567 void bpf_map_offload_map_free(struct bpf_map *map) 568 { 569 struct bpf_offloaded_map *offmap = map_to_offmap(map); 570 571 rtnl_lock(); 572 down_write(&bpf_devs_lock); 573 if (offmap->netdev) 574 __bpf_map_offload_destroy(offmap); 575 up_write(&bpf_devs_lock); 576 rtnl_unlock(); 577 578 bpf_map_area_free(offmap); 579 } 580 581 u64 bpf_map_offload_map_mem_usage(const struct bpf_map *map) 582 { 583 /* The memory dynamically allocated in netdev dev_ops is not counted */ 584 return sizeof(struct bpf_offloaded_map); 585 } 586 587 int bpf_map_offload_lookup_elem(struct bpf_map *map, void *key, void *value) 588 { 589 struct bpf_offloaded_map *offmap = map_to_offmap(map); 590 int ret = -ENODEV; 591 592 down_read(&bpf_devs_lock); 593 if (offmap->netdev) 594 ret = offmap->dev_ops->map_lookup_elem(offmap, key, value); 595 up_read(&bpf_devs_lock); 596 597 return ret; 598 } 599 600 int bpf_map_offload_update_elem(struct bpf_map *map, 601 void *key, void *value, u64 flags) 602 { 603 struct bpf_offloaded_map *offmap = map_to_offmap(map); 604 int ret = -ENODEV; 605 606 if (unlikely(flags > BPF_EXIST)) 607 return -EINVAL; 608 609 down_read(&bpf_devs_lock); 610 if (offmap->netdev) 611 ret = offmap->dev_ops->map_update_elem(offmap, key, value, 612 flags); 613 up_read(&bpf_devs_lock); 614 615 return ret; 616 } 617 618 int bpf_map_offload_delete_elem(struct bpf_map *map, void *key) 619 { 620 struct bpf_offloaded_map *offmap = map_to_offmap(map); 621 int ret = -ENODEV; 622 623 down_read(&bpf_devs_lock); 624 if (offmap->netdev) 625 ret = offmap->dev_ops->map_delete_elem(offmap, key); 626 up_read(&bpf_devs_lock); 627 628 return ret; 629 } 630 631 int bpf_map_offload_get_next_key(struct bpf_map *map, void *key, void *next_key) 632 { 633 struct bpf_offloaded_map *offmap = map_to_offmap(map); 634 int ret = -ENODEV; 635 636 down_read(&bpf_devs_lock); 637 if (offmap->netdev) 638 ret = offmap->dev_ops->map_get_next_key(offmap, key, next_key); 639 up_read(&bpf_devs_lock); 640 641 return ret; 642 } 643 644 struct ns_get_path_bpf_map_args { 645 struct bpf_offloaded_map *offmap; 646 struct bpf_map_info *info; 647 }; 648 649 static struct ns_common *bpf_map_offload_info_fill_ns(void *private_data) 650 { 651 struct ns_get_path_bpf_map_args *args = private_data; 652 struct ns_common *ns; 653 struct net *net; 654 655 rtnl_lock(); 656 down_read(&bpf_devs_lock); 657 658 if (args->offmap->netdev) { 659 args->info->ifindex = args->offmap->netdev->ifindex; 660 net = dev_net(args->offmap->netdev); 661 get_net(net); 662 ns = &net->ns; 663 } else { 664 args->info->ifindex = 0; 665 ns = NULL; 666 } 667 668 up_read(&bpf_devs_lock); 669 rtnl_unlock(); 670 671 return ns; 672 } 673 674 int bpf_map_offload_info_fill(struct bpf_map_info *info, struct bpf_map *map) 675 { 676 struct ns_get_path_bpf_map_args args = { 677 .offmap = map_to_offmap(map), 678 .info = info, 679 }; 680 struct inode *ns_inode; 681 struct path ns_path; 682 int res; 683 684 res = ns_get_path_cb(&ns_path, bpf_map_offload_info_fill_ns, &args); 685 if (res) { 686 if (!info->ifindex) 687 return -ENODEV; 688 return res; 689 } 690 691 ns_inode = ns_path.dentry->d_inode; 692 info->netns_dev = new_encode_dev(ns_inode->i_sb->s_dev); 693 info->netns_ino = ns_inode->i_ino; 694 path_put(&ns_path); 695 696 return 0; 697 } 698 699 static bool __bpf_offload_dev_match(struct bpf_prog *prog, 700 struct net_device *netdev) 701 { 702 struct bpf_offload_netdev *ondev1, *ondev2; 703 struct bpf_prog_offload *offload; 704 705 if (!bpf_prog_is_dev_bound(prog->aux)) 706 return false; 707 708 offload = prog->aux->offload; 709 if (!offload) 710 return false; 711 if (offload->netdev == netdev) 712 return true; 713 714 ondev1 = bpf_offload_find_netdev(offload->netdev); 715 ondev2 = bpf_offload_find_netdev(netdev); 716 717 return ondev1 && ondev2 && ondev1->offdev == ondev2->offdev; 718 } 719 720 bool bpf_offload_dev_match(struct bpf_prog *prog, struct net_device *netdev) 721 { 722 bool ret; 723 724 down_read(&bpf_devs_lock); 725 ret = __bpf_offload_dev_match(prog, netdev); 726 up_read(&bpf_devs_lock); 727 728 return ret; 729 } 730 EXPORT_SYMBOL_GPL(bpf_offload_dev_match); 731 732 bool bpf_prog_dev_bound_match(const struct bpf_prog *lhs, const struct bpf_prog *rhs) 733 { 734 bool ret; 735 736 if (bpf_prog_is_offloaded(lhs->aux) != bpf_prog_is_offloaded(rhs->aux)) 737 return false; 738 739 down_read(&bpf_devs_lock); 740 ret = lhs->aux->offload && rhs->aux->offload && 741 lhs->aux->offload->netdev && 742 lhs->aux->offload->netdev == rhs->aux->offload->netdev; 743 up_read(&bpf_devs_lock); 744 745 return ret; 746 } 747 748 bool bpf_offload_prog_map_match(struct bpf_prog *prog, struct bpf_map *map) 749 { 750 struct bpf_offloaded_map *offmap; 751 bool ret; 752 753 if (!bpf_map_is_offloaded(map)) 754 return bpf_map_offload_neutral(map); 755 offmap = map_to_offmap(map); 756 757 down_read(&bpf_devs_lock); 758 ret = __bpf_offload_dev_match(prog, offmap->netdev); 759 up_read(&bpf_devs_lock); 760 761 return ret; 762 } 763 764 int bpf_offload_dev_netdev_register(struct bpf_offload_dev *offdev, 765 struct net_device *netdev) 766 { 767 int err; 768 769 down_write(&bpf_devs_lock); 770 err = __bpf_offload_dev_netdev_register(offdev, netdev); 771 up_write(&bpf_devs_lock); 772 return err; 773 } 774 EXPORT_SYMBOL_GPL(bpf_offload_dev_netdev_register); 775 776 void bpf_offload_dev_netdev_unregister(struct bpf_offload_dev *offdev, 777 struct net_device *netdev) 778 { 779 down_write(&bpf_devs_lock); 780 __bpf_offload_dev_netdev_unregister(offdev, netdev); 781 up_write(&bpf_devs_lock); 782 } 783 EXPORT_SYMBOL_GPL(bpf_offload_dev_netdev_unregister); 784 785 struct bpf_offload_dev * 786 bpf_offload_dev_create(const struct bpf_prog_offload_ops *ops, void *priv) 787 { 788 struct bpf_offload_dev *offdev; 789 790 offdev = kzalloc(sizeof(*offdev), GFP_KERNEL); 791 if (!offdev) 792 return ERR_PTR(-ENOMEM); 793 794 offdev->ops = ops; 795 offdev->priv = priv; 796 INIT_LIST_HEAD(&offdev->netdevs); 797 798 return offdev; 799 } 800 EXPORT_SYMBOL_GPL(bpf_offload_dev_create); 801 802 void bpf_offload_dev_destroy(struct bpf_offload_dev *offdev) 803 { 804 WARN_ON(!list_empty(&offdev->netdevs)); 805 kfree(offdev); 806 } 807 EXPORT_SYMBOL_GPL(bpf_offload_dev_destroy); 808 809 void *bpf_offload_dev_priv(struct bpf_offload_dev *offdev) 810 { 811 return offdev->priv; 812 } 813 EXPORT_SYMBOL_GPL(bpf_offload_dev_priv); 814 815 void bpf_dev_bound_netdev_unregister(struct net_device *dev) 816 { 817 struct bpf_offload_netdev *ondev; 818 819 ASSERT_RTNL(); 820 821 down_write(&bpf_devs_lock); 822 ondev = bpf_offload_find_netdev(dev); 823 if (ondev && !ondev->offdev) 824 __bpf_offload_dev_netdev_unregister(NULL, ondev->netdev); 825 up_write(&bpf_devs_lock); 826 } 827 828 int bpf_dev_bound_kfunc_check(struct bpf_verifier_log *log, 829 struct bpf_prog_aux *prog_aux) 830 { 831 if (!bpf_prog_is_dev_bound(prog_aux)) { 832 bpf_log(log, "metadata kfuncs require device-bound program\n"); 833 return -EINVAL; 834 } 835 836 if (bpf_prog_is_offloaded(prog_aux)) { 837 bpf_log(log, "metadata kfuncs can't be offloaded\n"); 838 return -EINVAL; 839 } 840 841 return 0; 842 } 843 844 void *bpf_dev_bound_resolve_kfunc(struct bpf_prog *prog, u32 func_id) 845 { 846 const struct xdp_metadata_ops *ops; 847 void *p = NULL; 848 849 /* We don't hold bpf_devs_lock while resolving several 850 * kfuncs and can race with the unregister_netdevice(). 851 * We rely on bpf_dev_bound_match() check at attach 852 * to render this program unusable. 853 */ 854 down_read(&bpf_devs_lock); 855 if (!prog->aux->offload) 856 goto out; 857 858 ops = prog->aux->offload->netdev->xdp_metadata_ops; 859 if (!ops) 860 goto out; 861 862 #define XDP_METADATA_KFUNC(name, _, __, xmo) \ 863 if (func_id == bpf_xdp_metadata_kfunc_id(name)) p = ops->xmo; 864 XDP_METADATA_KFUNC_xxx 865 #undef XDP_METADATA_KFUNC 866 867 out: 868 up_read(&bpf_devs_lock); 869 870 return p; 871 } 872 873 static int __init bpf_offload_init(void) 874 { 875 return rhashtable_init(&offdevs, &offdevs_params); 876 } 877 878 core_initcall(bpf_offload_init); 879