1 // SPDX-License-Identifier: GPL-2.0 2 /* Copyright (c) 2017 - 2018 Covalent IO, Inc. http://covalent.io */ 3 4 #include <linux/skmsg.h> 5 #include <linux/filter.h> 6 #include <linux/bpf.h> 7 #include <linux/init.h> 8 #include <linux/wait.h> 9 #include <linux/util_macros.h> 10 11 #include <net/inet_common.h> 12 #include <net/tls.h> 13 #include <asm/ioctls.h> 14 15 void tcp_eat_skb(struct sock *sk, struct sk_buff *skb) 16 { 17 struct tcp_sock *tcp; 18 int copied; 19 20 if (!skb || !skb->len || !sk_is_tcp(sk)) 21 return; 22 23 if (skb_bpf_strparser(skb)) 24 return; 25 26 tcp = tcp_sk(sk); 27 copied = tcp->copied_seq + skb->len; 28 WRITE_ONCE(tcp->copied_seq, copied); 29 tcp_rcv_space_adjust(sk); 30 __tcp_cleanup_rbuf(sk, skb->len); 31 } 32 33 static int bpf_tcp_ingress(struct sock *sk, struct sk_psock *psock, 34 struct sk_msg *msg, u32 apply_bytes) 35 { 36 bool apply = apply_bytes; 37 struct scatterlist *sge; 38 u32 size, copied = 0; 39 struct sk_msg *tmp; 40 int i, ret = 0; 41 42 tmp = kzalloc(sizeof(*tmp), __GFP_NOWARN | GFP_KERNEL); 43 if (unlikely(!tmp)) 44 return -ENOMEM; 45 46 lock_sock(sk); 47 tmp->sg.start = msg->sg.start; 48 i = msg->sg.start; 49 do { 50 sge = sk_msg_elem(msg, i); 51 size = (apply && apply_bytes < sge->length) ? 52 apply_bytes : sge->length; 53 if (!__sk_rmem_schedule(sk, size, false)) { 54 if (!copied) 55 ret = -ENOMEM; 56 break; 57 } 58 59 sk_mem_charge(sk, size); 60 atomic_add(size, &sk->sk_rmem_alloc); 61 sk_msg_xfer(tmp, msg, i, size); 62 copied += size; 63 if (sge->length) 64 get_page(sk_msg_page(tmp, i)); 65 sk_msg_iter_var_next(i); 66 tmp->sg.end = i; 67 if (apply) { 68 apply_bytes -= size; 69 if (!apply_bytes) { 70 if (sge->length) 71 sk_msg_iter_var_prev(i); 72 break; 73 } 74 } 75 } while (i != msg->sg.end); 76 77 if (!ret) { 78 msg->sg.start = i; 79 if (!sk_psock_queue_msg(psock, tmp)) 80 atomic_sub(copied, &sk->sk_rmem_alloc); 81 sk_psock_data_ready(sk, psock); 82 } else { 83 sk_msg_free(sk, tmp); 84 kfree(tmp); 85 } 86 87 release_sock(sk); 88 return ret; 89 } 90 91 static int tcp_bpf_push(struct sock *sk, struct sk_msg *msg, u32 apply_bytes, 92 int flags, bool uncharge) 93 { 94 struct msghdr msghdr = {}; 95 bool apply = apply_bytes; 96 struct scatterlist *sge; 97 struct page *page; 98 int size, ret = 0; 99 u32 off; 100 101 while (1) { 102 struct bio_vec bvec; 103 bool has_tx_ulp; 104 105 sge = sk_msg_elem(msg, msg->sg.start); 106 size = (apply && apply_bytes < sge->length) ? 107 apply_bytes : sge->length; 108 off = sge->offset; 109 page = sg_page(sge); 110 111 tcp_rate_check_app_limited(sk); 112 retry: 113 msghdr.msg_flags = flags | MSG_SPLICE_PAGES; 114 has_tx_ulp = tls_sw_has_ctx_tx(sk); 115 if (has_tx_ulp) 116 msghdr.msg_flags |= MSG_SENDPAGE_NOPOLICY; 117 118 if (size < sge->length && msg->sg.start != msg->sg.end) 119 msghdr.msg_flags |= MSG_MORE; 120 121 bvec_set_page(&bvec, page, size, off); 122 iov_iter_bvec(&msghdr.msg_iter, ITER_SOURCE, &bvec, 1, size); 123 ret = tcp_sendmsg_locked(sk, &msghdr, size); 124 if (ret <= 0) 125 return ret; 126 127 if (apply) 128 apply_bytes -= ret; 129 msg->sg.size -= ret; 130 sge->offset += ret; 131 sge->length -= ret; 132 if (uncharge) 133 sk_mem_uncharge(sk, ret); 134 if (ret != size) { 135 size -= ret; 136 off += ret; 137 goto retry; 138 } 139 if (!sge->length) { 140 put_page(page); 141 sk_msg_iter_next(msg, start); 142 sg_init_table(sge, 1); 143 if (msg->sg.start == msg->sg.end) 144 break; 145 } 146 if (apply && !apply_bytes) 147 break; 148 } 149 150 return 0; 151 } 152 153 static int tcp_bpf_push_locked(struct sock *sk, struct sk_msg *msg, 154 u32 apply_bytes, int flags, bool uncharge) 155 { 156 int ret; 157 158 lock_sock(sk); 159 ret = tcp_bpf_push(sk, msg, apply_bytes, flags, uncharge); 160 release_sock(sk); 161 return ret; 162 } 163 164 int tcp_bpf_sendmsg_redir(struct sock *sk, bool ingress, 165 struct sk_msg *msg, u32 bytes, int flags) 166 { 167 struct sk_psock *psock = sk_psock_get(sk); 168 int ret; 169 170 if (unlikely(!psock)) 171 return -EPIPE; 172 173 ret = ingress ? bpf_tcp_ingress(sk, psock, msg, bytes) : 174 tcp_bpf_push_locked(sk, msg, bytes, flags, false); 175 sk_psock_put(sk, psock); 176 return ret; 177 } 178 EXPORT_SYMBOL_GPL(tcp_bpf_sendmsg_redir); 179 180 #ifdef CONFIG_BPF_SYSCALL 181 static int tcp_msg_wait_data(struct sock *sk, struct sk_psock *psock, 182 long timeo) 183 { 184 DEFINE_WAIT_FUNC(wait, woken_wake_function); 185 int ret = 0; 186 187 if (sk->sk_shutdown & RCV_SHUTDOWN) 188 return 1; 189 190 if (!timeo) 191 return ret; 192 193 add_wait_queue(sk_sleep(sk), &wait); 194 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk); 195 ret = sk_wait_event(sk, &timeo, 196 !list_empty(&psock->ingress_msg) || 197 !skb_queue_empty_lockless(&sk->sk_receive_queue), &wait); 198 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk); 199 remove_wait_queue(sk_sleep(sk), &wait); 200 return ret; 201 } 202 203 static bool is_next_msg_fin(struct sk_psock *psock) 204 { 205 struct scatterlist *sge; 206 struct sk_msg *msg_rx; 207 int i; 208 209 msg_rx = sk_psock_peek_msg(psock); 210 i = msg_rx->sg.start; 211 sge = sk_msg_elem(msg_rx, i); 212 if (!sge->length) { 213 struct sk_buff *skb = msg_rx->skb; 214 215 if (skb && TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) 216 return true; 217 } 218 return false; 219 } 220 221 static int tcp_bpf_recvmsg_parser(struct sock *sk, 222 struct msghdr *msg, 223 size_t len, 224 int flags, 225 int *addr_len) 226 { 227 int peek = flags & MSG_PEEK; 228 struct sk_psock *psock; 229 struct tcp_sock *tcp; 230 int copied_from_self = 0; 231 int copied = 0; 232 u32 seq; 233 234 if (unlikely(flags & MSG_ERRQUEUE)) 235 return inet_recv_error(sk, msg, len, addr_len); 236 237 if (!len) 238 return 0; 239 240 psock = sk_psock_get(sk); 241 if (unlikely(!psock)) 242 return tcp_recvmsg(sk, msg, len, flags, addr_len); 243 244 lock_sock(sk); 245 tcp = tcp_sk(sk); 246 seq = tcp->copied_seq; 247 /* We may have received data on the sk_receive_queue pre-accept and 248 * then we can not use read_skb in this context because we haven't 249 * assigned a sk_socket yet so have no link to the ops. The work-around 250 * is to check the sk_receive_queue and in these cases read skbs off 251 * queue again. The read_skb hook is not running at this point because 252 * of lock_sock so we avoid having multiple runners in read_skb. 253 */ 254 if (unlikely(!skb_queue_empty(&sk->sk_receive_queue))) { 255 tcp_data_ready(sk); 256 /* This handles the ENOMEM errors if we both receive data 257 * pre accept and are already under memory pressure. At least 258 * let user know to retry. 259 */ 260 if (unlikely(!skb_queue_empty(&sk->sk_receive_queue))) { 261 copied = -EAGAIN; 262 goto out; 263 } 264 } 265 266 msg_bytes_ready: 267 copied = __sk_msg_recvmsg(sk, psock, msg, len, flags, &copied_from_self); 268 /* The typical case for EFAULT is the socket was gracefully 269 * shutdown with a FIN pkt. So check here the other case is 270 * some error on copy_page_to_iter which would be unexpected. 271 * On fin return correct return code to zero. 272 */ 273 if (copied == -EFAULT) { 274 bool is_fin = is_next_msg_fin(psock); 275 276 if (is_fin) { 277 copied = 0; 278 seq++; 279 goto out; 280 } 281 } 282 seq += copied_from_self; 283 if (!copied) { 284 long timeo; 285 int data; 286 287 if (sock_flag(sk, SOCK_DONE)) 288 goto out; 289 290 if (sk->sk_err) { 291 copied = sock_error(sk); 292 goto out; 293 } 294 295 if (sk->sk_shutdown & RCV_SHUTDOWN) 296 goto out; 297 298 if (sk->sk_state == TCP_CLOSE) { 299 copied = -ENOTCONN; 300 goto out; 301 } 302 303 timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); 304 if (!timeo) { 305 copied = -EAGAIN; 306 goto out; 307 } 308 309 if (signal_pending(current)) { 310 copied = sock_intr_errno(timeo); 311 goto out; 312 } 313 314 data = tcp_msg_wait_data(sk, psock, timeo); 315 if (data < 0) { 316 copied = data; 317 goto unlock; 318 } 319 if (data && !sk_psock_queue_empty(psock)) 320 goto msg_bytes_ready; 321 copied = -EAGAIN; 322 } 323 out: 324 if (!peek) 325 WRITE_ONCE(tcp->copied_seq, seq); 326 tcp_rcv_space_adjust(sk); 327 if (copied > 0) 328 __tcp_cleanup_rbuf(sk, copied); 329 330 unlock: 331 release_sock(sk); 332 sk_psock_put(sk, psock); 333 return copied; 334 } 335 336 static int tcp_bpf_ioctl(struct sock *sk, int cmd, int *karg) 337 { 338 bool slow; 339 340 if (cmd != SIOCINQ) 341 return tcp_ioctl(sk, cmd, karg); 342 343 /* works similar as tcp_ioctl */ 344 if (sk->sk_state == TCP_LISTEN) 345 return -EINVAL; 346 347 slow = lock_sock_fast(sk); 348 *karg = sk_psock_msg_inq(sk); 349 unlock_sock_fast(sk, slow); 350 351 return 0; 352 } 353 354 static int tcp_bpf_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, 355 int flags, int *addr_len) 356 { 357 struct sk_psock *psock; 358 int copied, ret; 359 360 if (unlikely(flags & MSG_ERRQUEUE)) 361 return inet_recv_error(sk, msg, len, addr_len); 362 363 if (!len) 364 return 0; 365 366 psock = sk_psock_get(sk); 367 if (unlikely(!psock)) 368 return tcp_recvmsg(sk, msg, len, flags, addr_len); 369 if (!skb_queue_empty(&sk->sk_receive_queue) && 370 sk_psock_queue_empty(psock)) { 371 sk_psock_put(sk, psock); 372 return tcp_recvmsg(sk, msg, len, flags, addr_len); 373 } 374 lock_sock(sk); 375 msg_bytes_ready: 376 copied = sk_msg_recvmsg(sk, psock, msg, len, flags); 377 if (!copied) { 378 long timeo; 379 int data; 380 381 timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT); 382 data = tcp_msg_wait_data(sk, psock, timeo); 383 if (data < 0) { 384 ret = data; 385 goto unlock; 386 } 387 if (data) { 388 if (!sk_psock_queue_empty(psock)) 389 goto msg_bytes_ready; 390 release_sock(sk); 391 sk_psock_put(sk, psock); 392 return tcp_recvmsg(sk, msg, len, flags, addr_len); 393 } 394 copied = -EAGAIN; 395 } 396 ret = copied; 397 398 unlock: 399 release_sock(sk); 400 sk_psock_put(sk, psock); 401 return ret; 402 } 403 404 static int tcp_bpf_send_verdict(struct sock *sk, struct sk_psock *psock, 405 struct sk_msg *msg, int *copied, int flags) 406 { 407 bool cork = false, enospc = sk_msg_full(msg), redir_ingress; 408 struct sock *sk_redir; 409 u32 tosend, origsize, sent, delta = 0; 410 u32 eval; 411 int ret; 412 413 more_data: 414 if (psock->eval == __SK_NONE) { 415 /* Track delta in msg size to add/subtract it on SK_DROP from 416 * returned to user copied size. This ensures user doesn't 417 * get a positive return code with msg_cut_data and SK_DROP 418 * verdict. 419 */ 420 delta = msg->sg.size; 421 psock->eval = sk_psock_msg_verdict(sk, psock, msg); 422 delta -= msg->sg.size; 423 } 424 425 if (msg->cork_bytes && 426 msg->cork_bytes > msg->sg.size && !enospc) { 427 psock->cork_bytes = msg->cork_bytes - msg->sg.size; 428 if (!psock->cork) { 429 psock->cork = kzalloc(sizeof(*psock->cork), 430 GFP_ATOMIC | __GFP_NOWARN); 431 if (!psock->cork) { 432 sk_msg_free(sk, msg); 433 *copied = 0; 434 return -ENOMEM; 435 } 436 } 437 memcpy(psock->cork, msg, sizeof(*msg)); 438 return 0; 439 } 440 441 tosend = msg->sg.size; 442 if (psock->apply_bytes && psock->apply_bytes < tosend) 443 tosend = psock->apply_bytes; 444 eval = __SK_NONE; 445 446 switch (psock->eval) { 447 case __SK_PASS: 448 ret = tcp_bpf_push(sk, msg, tosend, flags, true); 449 if (unlikely(ret)) { 450 *copied -= sk_msg_free(sk, msg); 451 break; 452 } 453 sk_msg_apply_bytes(psock, tosend); 454 break; 455 case __SK_REDIRECT: 456 redir_ingress = psock->redir_ingress; 457 sk_redir = psock->sk_redir; 458 sk_msg_apply_bytes(psock, tosend); 459 if (!psock->apply_bytes) { 460 /* Clean up before releasing the sock lock. */ 461 eval = psock->eval; 462 psock->eval = __SK_NONE; 463 psock->sk_redir = NULL; 464 } 465 if (psock->cork) { 466 cork = true; 467 psock->cork = NULL; 468 } 469 release_sock(sk); 470 471 origsize = msg->sg.size; 472 ret = tcp_bpf_sendmsg_redir(sk_redir, redir_ingress, 473 msg, tosend, flags); 474 sent = origsize - msg->sg.size; 475 476 if (eval == __SK_REDIRECT) 477 sock_put(sk_redir); 478 479 lock_sock(sk); 480 sk_mem_uncharge(sk, sent); 481 if (unlikely(ret < 0)) { 482 int free = sk_msg_free(sk, msg); 483 484 if (!cork) 485 *copied -= free; 486 } 487 if (cork) { 488 sk_msg_free(sk, msg); 489 kfree(msg); 490 msg = NULL; 491 ret = 0; 492 } 493 break; 494 case __SK_DROP: 495 default: 496 sk_msg_free(sk, msg); 497 sk_msg_apply_bytes(psock, tosend); 498 *copied -= (tosend + delta); 499 return -EACCES; 500 } 501 502 if (likely(!ret)) { 503 if (!psock->apply_bytes) { 504 psock->eval = __SK_NONE; 505 if (psock->sk_redir) { 506 sock_put(psock->sk_redir); 507 psock->sk_redir = NULL; 508 } 509 } 510 if (msg && 511 msg->sg.data[msg->sg.start].page_link && 512 msg->sg.data[msg->sg.start].length) 513 goto more_data; 514 } 515 return ret; 516 } 517 518 static int tcp_bpf_sendmsg(struct sock *sk, struct msghdr *msg, size_t size) 519 { 520 struct sk_msg tmp, *msg_tx = NULL; 521 int copied = 0, err = 0, ret = 0; 522 struct sk_psock *psock; 523 long timeo; 524 int flags; 525 526 /* Don't let internal flags through */ 527 flags = (msg->msg_flags & ~MSG_SENDPAGE_DECRYPTED); 528 flags |= MSG_NO_SHARED_FRAGS; 529 530 psock = sk_psock_get(sk); 531 if (unlikely(!psock)) 532 return tcp_sendmsg(sk, msg, size); 533 534 lock_sock(sk); 535 timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); 536 while (msg_data_left(msg)) { 537 bool enospc = false; 538 u32 copy, osize; 539 540 if (sk->sk_err) { 541 err = -sk->sk_err; 542 goto out_err; 543 } 544 545 copy = msg_data_left(msg); 546 if (!sk_stream_memory_free(sk)) 547 goto wait_for_sndbuf; 548 if (psock->cork) { 549 msg_tx = psock->cork; 550 } else { 551 msg_tx = &tmp; 552 sk_msg_init(msg_tx); 553 } 554 555 osize = msg_tx->sg.size; 556 err = sk_msg_alloc(sk, msg_tx, msg_tx->sg.size + copy, msg_tx->sg.end - 1); 557 if (err) { 558 if (err != -ENOSPC) 559 goto wait_for_memory; 560 enospc = true; 561 copy = msg_tx->sg.size - osize; 562 } 563 564 ret = sk_msg_memcopy_from_iter(sk, &msg->msg_iter, msg_tx, 565 copy); 566 if (ret < 0) { 567 sk_msg_trim(sk, msg_tx, osize); 568 goto out_err; 569 } 570 571 copied += ret; 572 if (psock->cork_bytes) { 573 if (size > psock->cork_bytes) 574 psock->cork_bytes = 0; 575 else 576 psock->cork_bytes -= size; 577 if (psock->cork_bytes && !enospc) 578 goto out_err; 579 /* All cork bytes are accounted, rerun the prog. */ 580 psock->eval = __SK_NONE; 581 psock->cork_bytes = 0; 582 } 583 584 err = tcp_bpf_send_verdict(sk, psock, msg_tx, &copied, flags); 585 if (unlikely(err < 0)) 586 goto out_err; 587 continue; 588 wait_for_sndbuf: 589 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); 590 wait_for_memory: 591 err = sk_stream_wait_memory(sk, &timeo); 592 if (err) { 593 if (msg_tx && msg_tx != psock->cork) 594 sk_msg_free(sk, msg_tx); 595 goto out_err; 596 } 597 } 598 out_err: 599 if (err < 0) 600 err = sk_stream_error(sk, msg->msg_flags, err); 601 release_sock(sk); 602 sk_psock_put(sk, psock); 603 return copied > 0 ? copied : err; 604 } 605 606 enum { 607 TCP_BPF_IPV4, 608 TCP_BPF_IPV6, 609 TCP_BPF_NUM_PROTS, 610 }; 611 612 enum { 613 TCP_BPF_BASE, 614 TCP_BPF_TX, 615 TCP_BPF_RX, 616 TCP_BPF_TXRX, 617 TCP_BPF_NUM_CFGS, 618 }; 619 620 static struct proto *tcpv6_prot_saved __read_mostly; 621 static DEFINE_SPINLOCK(tcpv6_prot_lock); 622 static struct proto tcp_bpf_prots[TCP_BPF_NUM_PROTS][TCP_BPF_NUM_CFGS]; 623 624 static void tcp_bpf_rebuild_protos(struct proto prot[TCP_BPF_NUM_CFGS], 625 struct proto *base) 626 { 627 prot[TCP_BPF_BASE] = *base; 628 prot[TCP_BPF_BASE].destroy = sock_map_destroy; 629 prot[TCP_BPF_BASE].close = sock_map_close; 630 prot[TCP_BPF_BASE].recvmsg = tcp_bpf_recvmsg; 631 prot[TCP_BPF_BASE].sock_is_readable = sk_msg_is_readable; 632 prot[TCP_BPF_BASE].ioctl = tcp_bpf_ioctl; 633 634 prot[TCP_BPF_TX] = prot[TCP_BPF_BASE]; 635 prot[TCP_BPF_TX].sendmsg = tcp_bpf_sendmsg; 636 637 prot[TCP_BPF_RX] = prot[TCP_BPF_BASE]; 638 prot[TCP_BPF_RX].recvmsg = tcp_bpf_recvmsg_parser; 639 640 prot[TCP_BPF_TXRX] = prot[TCP_BPF_TX]; 641 prot[TCP_BPF_TXRX].recvmsg = tcp_bpf_recvmsg_parser; 642 } 643 644 static void tcp_bpf_check_v6_needs_rebuild(struct proto *ops) 645 { 646 if (unlikely(ops != smp_load_acquire(&tcpv6_prot_saved))) { 647 spin_lock_bh(&tcpv6_prot_lock); 648 if (likely(ops != tcpv6_prot_saved)) { 649 tcp_bpf_rebuild_protos(tcp_bpf_prots[TCP_BPF_IPV6], ops); 650 smp_store_release(&tcpv6_prot_saved, ops); 651 } 652 spin_unlock_bh(&tcpv6_prot_lock); 653 } 654 } 655 656 static int __init tcp_bpf_v4_build_proto(void) 657 { 658 tcp_bpf_rebuild_protos(tcp_bpf_prots[TCP_BPF_IPV4], &tcp_prot); 659 return 0; 660 } 661 late_initcall(tcp_bpf_v4_build_proto); 662 663 static int tcp_bpf_assert_proto_ops(struct proto *ops) 664 { 665 /* In order to avoid retpoline, we make assumptions when we call 666 * into ops if e.g. a psock is not present. Make sure they are 667 * indeed valid assumptions. 668 */ 669 return ops->recvmsg == tcp_recvmsg && 670 ops->sendmsg == tcp_sendmsg ? 0 : -ENOTSUPP; 671 } 672 673 #if IS_ENABLED(CONFIG_BPF_STREAM_PARSER) 674 int tcp_bpf_strp_read_sock(struct strparser *strp, read_descriptor_t *desc, 675 sk_read_actor_t recv_actor) 676 { 677 struct sock *sk = strp->sk; 678 struct sk_psock *psock; 679 struct tcp_sock *tp; 680 int copied = 0; 681 682 tp = tcp_sk(sk); 683 rcu_read_lock(); 684 psock = sk_psock(sk); 685 if (WARN_ON_ONCE(!psock)) { 686 desc->error = -EINVAL; 687 goto out; 688 } 689 690 psock->ingress_bytes = 0; 691 copied = tcp_read_sock_noack(sk, desc, recv_actor, true, 692 &psock->copied_seq); 693 if (copied < 0) 694 goto out; 695 /* recv_actor may redirect skb to another socket (SK_REDIRECT) or 696 * just put skb into ingress queue of current socket (SK_PASS). 697 * For SK_REDIRECT, we need to ack the frame immediately but for 698 * SK_PASS, we want to delay the ack until tcp_bpf_recvmsg_parser(). 699 */ 700 tp->copied_seq = psock->copied_seq - psock->ingress_bytes; 701 tcp_rcv_space_adjust(sk); 702 __tcp_cleanup_rbuf(sk, copied - psock->ingress_bytes); 703 out: 704 rcu_read_unlock(); 705 return copied; 706 } 707 #endif /* CONFIG_BPF_STREAM_PARSER */ 708 709 int tcp_bpf_update_proto(struct sock *sk, struct sk_psock *psock, bool restore) 710 { 711 int family = sk->sk_family == AF_INET6 ? TCP_BPF_IPV6 : TCP_BPF_IPV4; 712 int config = psock->progs.msg_parser ? TCP_BPF_TX : TCP_BPF_BASE; 713 714 if (psock->progs.stream_verdict || psock->progs.skb_verdict) { 715 config = (config == TCP_BPF_TX) ? TCP_BPF_TXRX : TCP_BPF_RX; 716 } 717 718 if (restore) { 719 if (inet_csk_has_ulp(sk)) { 720 /* TLS does not have an unhash proto in SW cases, 721 * but we need to ensure we stop using the sock_map 722 * unhash routine because the associated psock is being 723 * removed. So use the original unhash handler. 724 */ 725 WRITE_ONCE(sk->sk_prot->unhash, psock->saved_unhash); 726 tcp_update_ulp(sk, psock->sk_proto, psock->saved_write_space); 727 } else { 728 sk->sk_write_space = psock->saved_write_space; 729 /* Pairs with lockless read in sk_clone_lock() */ 730 sock_replace_proto(sk, psock->sk_proto); 731 } 732 return 0; 733 } 734 735 if (sk->sk_family == AF_INET6) { 736 if (tcp_bpf_assert_proto_ops(psock->sk_proto)) 737 return -EINVAL; 738 739 tcp_bpf_check_v6_needs_rebuild(psock->sk_proto); 740 } 741 742 /* Pairs with lockless read in sk_clone_lock() */ 743 sock_replace_proto(sk, &tcp_bpf_prots[family][config]); 744 return 0; 745 } 746 EXPORT_SYMBOL_GPL(tcp_bpf_update_proto); 747 748 /* If a child got cloned from a listening socket that had tcp_bpf 749 * protocol callbacks installed, we need to restore the callbacks to 750 * the default ones because the child does not inherit the psock state 751 * that tcp_bpf callbacks expect. 752 */ 753 void tcp_bpf_clone(const struct sock *sk, struct sock *newsk) 754 { 755 struct proto *prot = newsk->sk_prot; 756 757 if (is_insidevar(prot, tcp_bpf_prots)) 758 newsk->sk_prot = sk->sk_prot_creator; 759 } 760 #endif /* CONFIG_BPF_SYSCALL */ 761