1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 2007-2009 Google Inc. and Amit Singh 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions are 9 * met: 10 * 11 * * Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * * Redistributions in binary form must reproduce the above 14 * copyright notice, this list of conditions and the following disclaimer 15 * in the documentation and/or other materials provided with the 16 * distribution. 17 * * Neither the name of Google Inc. nor the names of its 18 * contributors may be used to endorse or promote products derived from 19 * this software without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 22 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 24 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 25 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 26 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 27 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 31 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 32 * 33 * Copyright (C) 2005 Csaba Henk. 34 * All rights reserved. 35 * 36 * Copyright (c) 2019 The FreeBSD Foundation 37 * 38 * Portions of this software were developed by BFF Storage Systems, LLC under 39 * sponsorship from the FreeBSD Foundation. 40 * 41 * Redistribution and use in source and binary forms, with or without 42 * modification, are permitted provided that the following conditions 43 * are met: 44 * 1. Redistributions of source code must retain the above copyright 45 * notice, this list of conditions and the following disclaimer. 46 * 2. Redistributions in binary form must reproduce the above copyright 47 * notice, this list of conditions and the following disclaimer in the 48 * documentation and/or other materials provided with the distribution. 49 * 50 * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND 51 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 52 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 53 * ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE 54 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 55 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 56 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 57 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 58 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 59 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 60 * SUCH DAMAGE. 61 */ 62 63 #include <sys/param.h> 64 #include <sys/module.h> 65 #include <sys/systm.h> 66 #include <sys/counter.h> 67 #include <sys/errno.h> 68 #include <sys/kernel.h> 69 #include <sys/conf.h> 70 #include <sys/uio.h> 71 #include <sys/malloc.h> 72 #include <sys/queue.h> 73 #include <sys/lock.h> 74 #include <sys/sx.h> 75 #include <sys/mutex.h> 76 #include <sys/proc.h> 77 #include <sys/mount.h> 78 #include <sys/sdt.h> 79 #include <sys/vnode.h> 80 #include <sys/signalvar.h> 81 #include <sys/syscallsubr.h> 82 #include <sys/sysctl.h> 83 #include <vm/uma.h> 84 85 #include "fuse.h" 86 #include "fuse_node.h" 87 #include "fuse_ipc.h" 88 #include "fuse_internal.h" 89 90 SDT_PROVIDER_DECLARE(fusefs); 91 /* 92 * Fuse trace probe: 93 * arg0: verbosity. Higher numbers give more verbose messages 94 * arg1: Textual message 95 */ 96 SDT_PROBE_DEFINE2(fusefs, , ipc, trace, "int", "char*"); 97 98 static void fdisp_make_pid(struct fuse_dispatcher *fdip, enum fuse_opcode op, 99 struct fuse_data *data, uint64_t nid, pid_t pid, struct ucred *cred); 100 static void fuse_interrupt_send(struct fuse_ticket *otick, int err); 101 static struct fuse_ticket *fticket_alloc(struct fuse_data *data); 102 static void fticket_refresh(struct fuse_ticket *ftick); 103 static inline void fticket_reset(struct fuse_ticket *ftick); 104 static void fticket_destroy(struct fuse_ticket *ftick); 105 static int fticket_wait_answer(struct fuse_ticket *ftick); 106 static inline int 107 fticket_aw_pull_uio(struct fuse_ticket *ftick, 108 struct uio *uio); 109 110 static int fuse_body_audit(struct fuse_ticket *ftick, size_t blen); 111 112 static fuse_handler_t fuse_standard_handler; 113 114 static counter_u64_t fuse_ticket_count; 115 SYSCTL_COUNTER_U64(_vfs_fusefs_stats, OID_AUTO, ticket_count, CTLFLAG_RD, 116 &fuse_ticket_count, "Number of allocated tickets"); 117 118 static long fuse_iov_permanent_bufsize = 1 << 19; 119 120 SYSCTL_LONG(_vfs_fusefs, OID_AUTO, iov_permanent_bufsize, CTLFLAG_RW, 121 &fuse_iov_permanent_bufsize, 0, 122 "limit for permanently stored buffer size for fuse_iovs"); 123 static int fuse_iov_credit = 16; 124 125 SYSCTL_INT(_vfs_fusefs, OID_AUTO, iov_credit, CTLFLAG_RW, 126 &fuse_iov_credit, 0, 127 "how many times is an oversized fuse_iov tolerated"); 128 129 MALLOC_DEFINE(M_FUSEMSG, "fuse_msgbuf", "fuse message buffer"); 130 static uma_zone_t ticket_zone; 131 132 /* 133 * TODO: figure out how to timeout INTERRUPT requests, because the daemon may 134 * leagally never respond 135 */ 136 static int 137 fuse_interrupt_callback(struct fuse_ticket *tick, struct uio *uio) 138 { 139 struct fuse_ticket *otick, *x_tick; 140 struct fuse_interrupt_in *fii; 141 struct fuse_data *data = tick->tk_data; 142 bool found = false; 143 144 fii = (struct fuse_interrupt_in*)((char*)tick->tk_ms_fiov.base + 145 sizeof(struct fuse_in_header)); 146 147 fuse_lck_mtx_lock(data->aw_mtx); 148 TAILQ_FOREACH_SAFE(otick, &data->aw_head, tk_aw_link, x_tick) { 149 if (otick->tk_unique == fii->unique) { 150 found = true; 151 break; 152 } 153 } 154 fuse_lck_mtx_unlock(data->aw_mtx); 155 156 if (!found) { 157 /* Original is already complete. Just return */ 158 return 0; 159 } 160 161 /* Clear the original ticket's interrupt association */ 162 otick->irq_unique = 0; 163 164 if (tick->tk_aw_ohead.error == ENOSYS) { 165 fsess_set_notimpl(data->mp, FUSE_INTERRUPT); 166 return 0; 167 } else if (tick->tk_aw_ohead.error == EAGAIN) { 168 /* 169 * There are two reasons we might get this: 170 * 1) the daemon received the INTERRUPT request before the 171 * original, or 172 * 2) the daemon received the INTERRUPT request after it 173 * completed the original request. 174 * In the first case we should re-send the INTERRUPT. In the 175 * second, we should ignore it. 176 */ 177 /* Resend */ 178 fuse_interrupt_send(otick, EINTR); 179 return 0; 180 } else { 181 /* Illegal FUSE_INTERRUPT response */ 182 return EINVAL; 183 } 184 } 185 186 /* Interrupt the operation otick. Return err as its error code */ 187 void 188 fuse_interrupt_send(struct fuse_ticket *otick, int err) 189 { 190 struct fuse_dispatcher fdi; 191 struct fuse_interrupt_in *fii; 192 struct fuse_in_header *ftick_hdr; 193 struct fuse_data *data = otick->tk_data; 194 struct fuse_ticket *tick, *xtick; 195 struct ucred reused_creds; 196 197 if (otick->irq_unique == 0) { 198 /* 199 * If the daemon hasn't yet received otick, then we can answer 200 * it ourselves and return. 201 */ 202 fuse_lck_mtx_lock(data->ms_mtx); 203 STAILQ_FOREACH_SAFE(tick, &otick->tk_data->ms_head, tk_ms_link, 204 xtick) { 205 if (tick == otick) { 206 STAILQ_REMOVE(&otick->tk_data->ms_head, tick, 207 fuse_ticket, tk_ms_link); 208 otick->tk_data->ms_count--; 209 otick->tk_ms_link.stqe_next = NULL; 210 fuse_lck_mtx_unlock(data->ms_mtx); 211 212 fuse_lck_mtx_lock(otick->tk_aw_mtx); 213 if (!fticket_answered(otick)) { 214 fticket_set_answered(otick); 215 otick->tk_aw_errno = err; 216 wakeup(otick); 217 } 218 fuse_lck_mtx_unlock(otick->tk_aw_mtx); 219 220 fuse_ticket_drop(tick); 221 return; 222 } 223 } 224 fuse_lck_mtx_unlock(data->ms_mtx); 225 226 /* 227 * If the fuse daemon doesn't support interrupts, then there's 228 * nothing more that we can do 229 */ 230 if (fsess_not_impl(data->mp, FUSE_INTERRUPT)) 231 return; 232 233 /* 234 * If the fuse daemon has already received otick, then we must 235 * send FUSE_INTERRUPT. 236 */ 237 ftick_hdr = fticket_in_header(otick); 238 reused_creds.cr_uid = ftick_hdr->uid; 239 reused_creds.cr_gid = ftick_hdr->gid; 240 fdisp_init(&fdi, sizeof(*fii)); 241 fdisp_make_pid(&fdi, FUSE_INTERRUPT, data, ftick_hdr->nodeid, 242 ftick_hdr->pid, &reused_creds); 243 244 fii = fdi.indata; 245 fii->unique = otick->tk_unique; 246 fuse_insert_callback(fdi.tick, fuse_interrupt_callback); 247 248 otick->irq_unique = fdi.tick->tk_unique; 249 /* Interrupt ops should be delivered ASAP */ 250 fuse_insert_message(fdi.tick, true); 251 fdisp_destroy(&fdi); 252 } else { 253 /* This ticket has already been interrupted */ 254 } 255 } 256 257 void 258 fiov_init(struct fuse_iov *fiov, size_t size) 259 { 260 uint32_t msize = FU_AT_LEAST(size); 261 262 fiov->len = 0; 263 264 fiov->base = malloc(msize, M_FUSEMSG, M_WAITOK | M_ZERO); 265 266 fiov->allocated_size = msize; 267 fiov->credit = fuse_iov_credit; 268 } 269 270 void 271 fiov_teardown(struct fuse_iov *fiov) 272 { 273 MPASS(fiov->base != NULL); 274 free(fiov->base, M_FUSEMSG); 275 } 276 277 void 278 fiov_adjust(struct fuse_iov *fiov, size_t size) 279 { 280 if (fiov->allocated_size < size || 281 (fuse_iov_permanent_bufsize >= 0 && 282 fiov->allocated_size - size > fuse_iov_permanent_bufsize && 283 --fiov->credit < 0)) { 284 fiov->base = realloc(fiov->base, FU_AT_LEAST(size), M_FUSEMSG, 285 M_WAITOK | M_ZERO); 286 if (!fiov->base) { 287 panic("FUSE: realloc failed"); 288 } 289 fiov->allocated_size = FU_AT_LEAST(size); 290 fiov->credit = fuse_iov_credit; 291 /* Clear data buffer after reallocation */ 292 bzero(fiov->base, size); 293 } else if (size > fiov->len) { 294 /* Clear newly extended portion of data buffer */ 295 bzero((char*)fiov->base + fiov->len, size - fiov->len); 296 } 297 fiov->len = size; 298 } 299 300 /* Resize the fiov if needed, and clear it's buffer */ 301 void 302 fiov_refresh(struct fuse_iov *fiov) 303 { 304 fiov_adjust(fiov, 0); 305 } 306 307 static int 308 fticket_ctor(void *mem, int size, void *arg, int flags) 309 { 310 struct fuse_ticket *ftick = mem; 311 struct fuse_data *data = arg; 312 313 FUSE_ASSERT_MS_DONE(ftick); 314 FUSE_ASSERT_AW_DONE(ftick); 315 316 ftick->tk_data = data; 317 ftick->irq_unique = 0; 318 refcount_init(&ftick->tk_refcount, 1); 319 counter_u64_add(fuse_ticket_count, 1); 320 321 fticket_refresh(ftick); 322 323 return 0; 324 } 325 326 static void 327 fticket_dtor(void *mem, int size, void *arg) 328 { 329 #ifdef INVARIANTS 330 struct fuse_ticket *ftick = mem; 331 #endif 332 333 FUSE_ASSERT_MS_DONE(ftick); 334 FUSE_ASSERT_AW_DONE(ftick); 335 336 counter_u64_add(fuse_ticket_count, -1); 337 } 338 339 static int 340 fticket_init(void *mem, int size, int flags) 341 { 342 struct fuse_ticket *ftick = mem; 343 344 bzero(ftick, sizeof(struct fuse_ticket)); 345 346 fiov_init(&ftick->tk_ms_fiov, sizeof(struct fuse_in_header)); 347 348 mtx_init(&ftick->tk_aw_mtx, "fuse answer delivery mutex", NULL, MTX_DEF); 349 fiov_init(&ftick->tk_aw_fiov, 0); 350 351 return 0; 352 } 353 354 static void 355 fticket_fini(void *mem, int size) 356 { 357 struct fuse_ticket *ftick = mem; 358 359 fiov_teardown(&ftick->tk_ms_fiov); 360 fiov_teardown(&ftick->tk_aw_fiov); 361 mtx_destroy(&ftick->tk_aw_mtx); 362 } 363 364 static inline struct fuse_ticket * 365 fticket_alloc(struct fuse_data *data) 366 { 367 return uma_zalloc_arg(ticket_zone, data, M_WAITOK); 368 } 369 370 static inline void 371 fticket_destroy(struct fuse_ticket *ftick) 372 { 373 return uma_zfree(ticket_zone, ftick); 374 } 375 376 /* Prepare the ticket to be reused and clear its data buffers */ 377 static inline void 378 fticket_refresh(struct fuse_ticket *ftick) 379 { 380 fticket_reset(ftick); 381 382 fiov_refresh(&ftick->tk_ms_fiov); 383 fiov_refresh(&ftick->tk_aw_fiov); 384 } 385 386 /* Prepare the ticket to be reused, but don't clear its data buffers */ 387 static inline void 388 fticket_reset(struct fuse_ticket *ftick) 389 { 390 struct fuse_data *data = ftick->tk_data; 391 392 FUSE_ASSERT_MS_DONE(ftick); 393 FUSE_ASSERT_AW_DONE(ftick); 394 395 bzero(&ftick->tk_aw_ohead, sizeof(struct fuse_out_header)); 396 397 ftick->tk_aw_errno = 0; 398 ftick->tk_flag = 0; 399 400 /* May be truncated to 32 bits on LP32 arches */ 401 ftick->tk_unique = atomic_fetchadd_long(&data->ticketer, 1); 402 if (ftick->tk_unique == 0) 403 ftick->tk_unique = atomic_fetchadd_long(&data->ticketer, 1); 404 } 405 406 static int 407 fticket_wait_answer(struct fuse_ticket *ftick) 408 { 409 struct thread *td = curthread; 410 sigset_t blockedset, oldset; 411 int err = 0, stops_deferred; 412 struct fuse_data *data = ftick->tk_data; 413 bool interrupted = false; 414 415 if (fsess_maybe_impl(ftick->tk_data->mp, FUSE_INTERRUPT) && 416 data->dataflags & FSESS_INTR) { 417 SIGEMPTYSET(blockedset); 418 } else { 419 /* Block all signals except (implicitly) SIGKILL */ 420 SIGFILLSET(blockedset); 421 } 422 stops_deferred = sigdeferstop(SIGDEFERSTOP_SILENT); 423 kern_sigprocmask(td, SIG_BLOCK, NULL, &oldset, 0); 424 425 fuse_lck_mtx_lock(ftick->tk_aw_mtx); 426 427 retry: 428 if (fticket_answered(ftick)) { 429 goto out; 430 } 431 432 if (fdata_get_dead(data)) { 433 err = ENOTCONN; 434 fticket_set_answered(ftick); 435 goto out; 436 } 437 kern_sigprocmask(td, SIG_BLOCK, &blockedset, NULL, 0); 438 err = msleep(ftick, &ftick->tk_aw_mtx, PCATCH, "fu_ans", 439 data->daemon_timeout * hz); 440 kern_sigprocmask(td, SIG_SETMASK, &oldset, NULL, 0); 441 if (err == EWOULDBLOCK) { 442 SDT_PROBE2(fusefs, , ipc, trace, 3, 443 "fticket_wait_answer: EWOULDBLOCK"); 444 err = ETIMEDOUT; 445 fticket_set_answered(ftick); 446 } else if ((err == EINTR || err == ERESTART)) { 447 /* 448 * Whether we get EINTR or ERESTART depends on whether 449 * SA_RESTART was set by sigaction(2). 450 * 451 * Try to interrupt the operation and wait for an EINTR response 452 * to the original operation. If the file system does not 453 * support FUSE_INTERRUPT, then we'll just wait for it to 454 * complete like normal. If it does support FUSE_INTERRUPT, 455 * then it will either respond EINTR to the original operation, 456 * or EAGAIN to the interrupt. 457 */ 458 sigset_t tmpset; 459 460 SDT_PROBE2(fusefs, , ipc, trace, 4, 461 "fticket_wait_answer: interrupt"); 462 fuse_lck_mtx_unlock(ftick->tk_aw_mtx); 463 fuse_interrupt_send(ftick, err); 464 465 PROC_LOCK(td->td_proc); 466 mtx_lock(&td->td_proc->p_sigacts->ps_mtx); 467 tmpset = td->td_proc->p_siglist; 468 SIGSETOR(tmpset, td->td_siglist); 469 mtx_unlock(&td->td_proc->p_sigacts->ps_mtx); 470 PROC_UNLOCK(td->td_proc); 471 472 fuse_lck_mtx_lock(ftick->tk_aw_mtx); 473 if (!interrupted && !SIGISMEMBER(tmpset, SIGKILL)) { 474 /* 475 * Block all signals while we wait for an interrupt 476 * response. The protocol doesn't discriminate between 477 * different signals. 478 */ 479 SIGFILLSET(blockedset); 480 interrupted = true; 481 goto retry; 482 } else { 483 /* 484 * Return immediately for fatal signals, or if this is 485 * the second interruption. We should only be 486 * interrupted twice if the thread is stopped, for 487 * example during sigexit. 488 */ 489 } 490 } else if (err) { 491 SDT_PROBE2(fusefs, , ipc, trace, 6, 492 "fticket_wait_answer: other error"); 493 } else { 494 SDT_PROBE2(fusefs, , ipc, trace, 7, "fticket_wait_answer: OK"); 495 } 496 out: 497 if (!(err || fticket_answered(ftick))) { 498 SDT_PROBE2(fusefs, , ipc, trace, 1, 499 "FUSE: requester was woken up but still no answer"); 500 err = ENXIO; 501 } 502 fuse_lck_mtx_unlock(ftick->tk_aw_mtx); 503 sigallowstop(stops_deferred); 504 505 return err; 506 } 507 508 static inline 509 int 510 fticket_aw_pull_uio(struct fuse_ticket *ftick, struct uio *uio) 511 { 512 int err = 0; 513 size_t len = uio_resid(uio); 514 515 if (len) { 516 fiov_adjust(fticket_resp(ftick), len); 517 err = uiomove(fticket_resp(ftick)->base, len, uio); 518 } 519 return err; 520 } 521 522 int 523 fticket_pull(struct fuse_ticket *ftick, struct uio *uio) 524 { 525 int err = 0; 526 527 if (ftick->tk_aw_ohead.error) { 528 return 0; 529 } 530 err = fuse_body_audit(ftick, uio_resid(uio)); 531 if (!err) { 532 err = fticket_aw_pull_uio(ftick, uio); 533 } 534 return err; 535 } 536 537 struct fuse_data * 538 fdata_alloc(struct cdev *fdev, struct ucred *cred) 539 { 540 struct fuse_data *data; 541 542 data = malloc(sizeof(struct fuse_data), M_FUSEMSG, M_WAITOK | M_ZERO); 543 544 data->fdev = fdev; 545 mtx_init(&data->ms_mtx, "fuse message list mutex", NULL, MTX_DEF); 546 STAILQ_INIT(&data->ms_head); 547 data->ms_count = 0; 548 knlist_init_mtx(&data->ks_rsel.si_note, &data->ms_mtx); 549 mtx_init(&data->aw_mtx, "fuse answer list mutex", NULL, MTX_DEF); 550 TAILQ_INIT(&data->aw_head); 551 data->daemoncred = crhold(cred); 552 data->daemon_timeout = FUSE_DEFAULT_DAEMON_TIMEOUT; 553 data->ref = 1; 554 555 return data; 556 } 557 558 void 559 fdata_trydestroy(struct fuse_data *data) 560 { 561 data->ref--; 562 MPASS(data->ref >= 0); 563 if (data->ref != 0) 564 return; 565 566 /* Driving off stage all that stuff thrown at device... */ 567 crfree(data->daemoncred); 568 mtx_destroy(&data->aw_mtx); 569 knlist_delete(&data->ks_rsel.si_note, curthread, 0); 570 knlist_destroy(&data->ks_rsel.si_note); 571 mtx_destroy(&data->ms_mtx); 572 573 free(data, M_FUSEMSG); 574 } 575 576 void 577 fdata_set_dead(struct fuse_data *data) 578 { 579 FUSE_LOCK(); 580 if (fdata_get_dead(data)) { 581 FUSE_UNLOCK(); 582 return; 583 } 584 fuse_lck_mtx_lock(data->ms_mtx); 585 data->dataflags |= FSESS_DEAD; 586 wakeup_one(data); 587 selwakeuppri(&data->ks_rsel, PZERO); 588 wakeup(&data->ticketer); 589 fuse_lck_mtx_unlock(data->ms_mtx); 590 FUSE_UNLOCK(); 591 } 592 593 struct fuse_ticket * 594 fuse_ticket_fetch(struct fuse_data *data) 595 { 596 int err = 0; 597 struct fuse_ticket *ftick; 598 599 ftick = fticket_alloc(data); 600 601 if (!(data->dataflags & FSESS_INITED)) { 602 /* Sleep until get answer for INIT message */ 603 FUSE_LOCK(); 604 if (!(data->dataflags & FSESS_INITED) && data->ticketer > 2) { 605 err = msleep(&data->ticketer, &fuse_mtx, PCATCH | PDROP, 606 "fu_ini", 0); 607 if (err) 608 fdata_set_dead(data); 609 } else 610 FUSE_UNLOCK(); 611 } 612 return ftick; 613 } 614 615 int 616 fuse_ticket_drop(struct fuse_ticket *ftick) 617 { 618 int die; 619 620 die = refcount_release(&ftick->tk_refcount); 621 if (die) 622 fticket_destroy(ftick); 623 624 return die; 625 } 626 627 void 628 fuse_insert_callback(struct fuse_ticket *ftick, fuse_handler_t * handler) 629 { 630 if (fdata_get_dead(ftick->tk_data)) { 631 return; 632 } 633 ftick->tk_aw_handler = handler; 634 635 fuse_lck_mtx_lock(ftick->tk_data->aw_mtx); 636 fuse_aw_push(ftick); 637 fuse_lck_mtx_unlock(ftick->tk_data->aw_mtx); 638 } 639 640 /* 641 * Insert a new upgoing ticket into the message queue 642 * 643 * If urgent is true, insert at the front of the queue. Otherwise, insert in 644 * FIFO order. 645 */ 646 void 647 fuse_insert_message(struct fuse_ticket *ftick, bool urgent) 648 { 649 if (ftick->tk_flag & FT_DIRTY) { 650 panic("FUSE: ticket reused without being refreshed"); 651 } 652 ftick->tk_flag |= FT_DIRTY; 653 654 if (fdata_get_dead(ftick->tk_data)) { 655 return; 656 } 657 fuse_lck_mtx_lock(ftick->tk_data->ms_mtx); 658 if (urgent) 659 fuse_ms_push_head(ftick); 660 else 661 fuse_ms_push(ftick); 662 wakeup_one(ftick->tk_data); 663 selwakeuppri(&ftick->tk_data->ks_rsel, PZERO); 664 KNOTE_LOCKED(&ftick->tk_data->ks_rsel.si_note, 0); 665 fuse_lck_mtx_unlock(ftick->tk_data->ms_mtx); 666 } 667 668 static int 669 fuse_body_audit(struct fuse_ticket *ftick, size_t blen) 670 { 671 int err = 0; 672 enum fuse_opcode opcode; 673 674 opcode = fticket_opcode(ftick); 675 676 switch (opcode) { 677 case FUSE_BMAP: 678 err = (blen == sizeof(struct fuse_bmap_out)) ? 0 : EINVAL; 679 break; 680 681 case FUSE_LINK: 682 case FUSE_LOOKUP: 683 case FUSE_MKDIR: 684 case FUSE_MKNOD: 685 case FUSE_SYMLINK: 686 if (fuse_libabi_geq(ftick->tk_data, 7, 9)) { 687 err = (blen == sizeof(struct fuse_entry_out)) ? 688 0 : EINVAL; 689 } else { 690 err = (blen == FUSE_COMPAT_ENTRY_OUT_SIZE) ? 0 : EINVAL; 691 } 692 break; 693 694 case FUSE_FORGET: 695 panic("FUSE: a handler has been installed for FUSE_FORGET"); 696 break; 697 698 case FUSE_GETATTR: 699 case FUSE_SETATTR: 700 if (fuse_libabi_geq(ftick->tk_data, 7, 9)) { 701 err = (blen == sizeof(struct fuse_attr_out)) ? 702 0 : EINVAL; 703 } else { 704 err = (blen == FUSE_COMPAT_ATTR_OUT_SIZE) ? 0 : EINVAL; 705 } 706 break; 707 708 case FUSE_READLINK: 709 err = (PAGE_SIZE >= blen) ? 0 : EINVAL; 710 break; 711 712 case FUSE_UNLINK: 713 err = (blen == 0) ? 0 : EINVAL; 714 break; 715 716 case FUSE_RMDIR: 717 err = (blen == 0) ? 0 : EINVAL; 718 break; 719 720 case FUSE_RENAME: 721 err = (blen == 0) ? 0 : EINVAL; 722 break; 723 724 case FUSE_OPEN: 725 err = (blen == sizeof(struct fuse_open_out)) ? 0 : EINVAL; 726 break; 727 728 case FUSE_READ: 729 err = (((struct fuse_read_in *)( 730 (char *)ftick->tk_ms_fiov.base + 731 sizeof(struct fuse_in_header) 732 ))->size >= blen) ? 0 : EINVAL; 733 break; 734 735 case FUSE_WRITE: 736 err = (blen == sizeof(struct fuse_write_out)) ? 0 : EINVAL; 737 break; 738 739 case FUSE_STATFS: 740 if (fuse_libabi_geq(ftick->tk_data, 7, 4)) { 741 err = (blen == sizeof(struct fuse_statfs_out)) ? 742 0 : EINVAL; 743 } else { 744 err = (blen == FUSE_COMPAT_STATFS_SIZE) ? 0 : EINVAL; 745 } 746 break; 747 748 case FUSE_RELEASE: 749 err = (blen == 0) ? 0 : EINVAL; 750 break; 751 752 case FUSE_FSYNC: 753 err = (blen == 0) ? 0 : EINVAL; 754 break; 755 756 case FUSE_SETXATTR: 757 err = (blen == 0) ? 0 : EINVAL; 758 break; 759 760 case FUSE_GETXATTR: 761 case FUSE_LISTXATTR: 762 /* 763 * These can have varying response lengths, and 0 length 764 * isn't necessarily invalid. 765 */ 766 err = 0; 767 break; 768 769 case FUSE_REMOVEXATTR: 770 err = (blen == 0) ? 0 : EINVAL; 771 break; 772 773 case FUSE_FLUSH: 774 err = (blen == 0) ? 0 : EINVAL; 775 break; 776 777 case FUSE_INIT: 778 if (blen == sizeof(struct fuse_init_out) || 779 blen == FUSE_COMPAT_INIT_OUT_SIZE || 780 blen == FUSE_COMPAT_22_INIT_OUT_SIZE) { 781 err = 0; 782 } else { 783 err = EINVAL; 784 } 785 break; 786 787 case FUSE_OPENDIR: 788 err = (blen == sizeof(struct fuse_open_out)) ? 0 : EINVAL; 789 break; 790 791 case FUSE_READDIR: 792 err = (((struct fuse_read_in *)( 793 (char *)ftick->tk_ms_fiov.base + 794 sizeof(struct fuse_in_header) 795 ))->size >= blen) ? 0 : EINVAL; 796 break; 797 798 case FUSE_RELEASEDIR: 799 err = (blen == 0) ? 0 : EINVAL; 800 break; 801 802 case FUSE_FSYNCDIR: 803 err = (blen == 0) ? 0 : EINVAL; 804 break; 805 806 case FUSE_GETLK: 807 err = (blen == sizeof(struct fuse_lk_out)) ? 0 : EINVAL; 808 break; 809 810 case FUSE_SETLK: 811 err = (blen == 0) ? 0 : EINVAL; 812 break; 813 814 case FUSE_SETLKW: 815 err = (blen == 0) ? 0 : EINVAL; 816 break; 817 818 case FUSE_ACCESS: 819 err = (blen == 0) ? 0 : EINVAL; 820 break; 821 822 case FUSE_CREATE: 823 if (fuse_libabi_geq(ftick->tk_data, 7, 9)) { 824 err = (blen == sizeof(struct fuse_entry_out) + 825 sizeof(struct fuse_open_out)) ? 0 : EINVAL; 826 } else { 827 err = (blen == FUSE_COMPAT_ENTRY_OUT_SIZE + 828 sizeof(struct fuse_open_out)) ? 0 : EINVAL; 829 } 830 break; 831 832 case FUSE_DESTROY: 833 err = (blen == 0) ? 0 : EINVAL; 834 break; 835 836 case FUSE_IOCTL: 837 err = (blen >= sizeof(struct fuse_ioctl_out)) ? 0 : EINVAL; 838 break; 839 840 case FUSE_FALLOCATE: 841 err = (blen == 0) ? 0 : EINVAL; 842 break; 843 844 case FUSE_LSEEK: 845 err = (blen == sizeof(struct fuse_lseek_out)) ? 0 : EINVAL; 846 break; 847 848 case FUSE_COPY_FILE_RANGE: 849 err = (blen == sizeof(struct fuse_write_out)) ? 0 : EINVAL; 850 break; 851 852 default: 853 panic("FUSE: opcodes out of sync (%d)\n", opcode); 854 } 855 856 return err; 857 } 858 859 static inline void 860 fuse_setup_ihead(struct fuse_in_header *ihead, struct fuse_ticket *ftick, 861 uint64_t nid, enum fuse_opcode op, size_t blen, pid_t pid, 862 struct ucred *cred) 863 { 864 ihead->len = sizeof(*ihead) + blen; 865 ihead->unique = ftick->tk_unique; 866 ihead->nodeid = nid; 867 ihead->opcode = op; 868 869 ihead->pid = pid; 870 ihead->uid = cred->cr_uid; 871 ihead->gid = cred->cr_gid; 872 } 873 874 /* 875 * fuse_standard_handler just pulls indata and wakes up pretender. 876 * Doesn't try to interpret data, that's left for the pretender. 877 * Though might do a basic size verification before the pull-in takes place 878 */ 879 880 static int 881 fuse_standard_handler(struct fuse_ticket *ftick, struct uio *uio) 882 { 883 int err = 0; 884 885 err = fticket_pull(ftick, uio); 886 887 fuse_lck_mtx_lock(ftick->tk_aw_mtx); 888 889 if (!fticket_answered(ftick)) { 890 fticket_set_answered(ftick); 891 ftick->tk_aw_errno = err; 892 wakeup(ftick); 893 } 894 fuse_lck_mtx_unlock(ftick->tk_aw_mtx); 895 896 return err; 897 } 898 899 /* 900 * Reinitialize a dispatcher from a pid and node id, without resizing or 901 * clearing its data buffers 902 */ 903 static void 904 fdisp_refresh_pid(struct fuse_dispatcher *fdip, enum fuse_opcode op, 905 struct mount *mp, uint64_t nid, pid_t pid, struct ucred *cred) 906 { 907 MPASS(fdip->tick); 908 MPASS2(sizeof(fdip->finh) + fdip->iosize <= fdip->tick->tk_ms_fiov.len, 909 "Must use fdisp_make_pid to increase the size of the fiov"); 910 fticket_reset(fdip->tick); 911 912 FUSE_DIMALLOC(&fdip->tick->tk_ms_fiov, fdip->finh, 913 fdip->indata, fdip->iosize); 914 915 fuse_setup_ihead(fdip->finh, fdip->tick, nid, op, fdip->iosize, pid, 916 cred); 917 } 918 919 /* Initialize a dispatcher from a pid and node id */ 920 static void 921 fdisp_make_pid(struct fuse_dispatcher *fdip, enum fuse_opcode op, 922 struct fuse_data *data, uint64_t nid, pid_t pid, struct ucred *cred) 923 { 924 if (fdip->tick) { 925 fticket_refresh(fdip->tick); 926 } else { 927 fdip->tick = fuse_ticket_fetch(data); 928 } 929 930 /* FUSE_DIMALLOC will bzero the fiovs when it enlarges them */ 931 FUSE_DIMALLOC(&fdip->tick->tk_ms_fiov, fdip->finh, 932 fdip->indata, fdip->iosize); 933 934 fuse_setup_ihead(fdip->finh, fdip->tick, nid, op, fdip->iosize, pid, cred); 935 } 936 937 void 938 fdisp_make(struct fuse_dispatcher *fdip, enum fuse_opcode op, struct mount *mp, 939 uint64_t nid, struct thread *td, struct ucred *cred) 940 { 941 struct fuse_data *data = fuse_get_mpdata(mp); 942 RECTIFY_TDCR(td, cred); 943 944 return fdisp_make_pid(fdip, op, data, nid, td->td_proc->p_pid, cred); 945 } 946 947 void 948 fdisp_make_vp(struct fuse_dispatcher *fdip, enum fuse_opcode op, 949 struct vnode *vp, struct thread *td, struct ucred *cred) 950 { 951 struct mount *mp = vnode_mount(vp); 952 struct fuse_data *data = fuse_get_mpdata(mp); 953 954 RECTIFY_TDCR(td, cred); 955 return fdisp_make_pid(fdip, op, data, VTOI(vp), 956 td->td_proc->p_pid, cred); 957 } 958 959 /* Refresh a fuse_dispatcher so it can be reused, but don't zero its data */ 960 void 961 fdisp_refresh_vp(struct fuse_dispatcher *fdip, enum fuse_opcode op, 962 struct vnode *vp, struct thread *td, struct ucred *cred) 963 { 964 RECTIFY_TDCR(td, cred); 965 return fdisp_refresh_pid(fdip, op, vnode_mount(vp), VTOI(vp), 966 td->td_proc->p_pid, cred); 967 } 968 969 SDT_PROBE_DEFINE2(fusefs, , ipc, fdisp_wait_answ_error, "char*", "int"); 970 971 int 972 fdisp_wait_answ(struct fuse_dispatcher *fdip) 973 { 974 int err = 0; 975 976 fdip->answ_stat = 0; 977 fuse_insert_callback(fdip->tick, fuse_standard_handler); 978 fuse_insert_message(fdip->tick, false); 979 980 if ((err = fticket_wait_answer(fdip->tick))) { 981 fuse_lck_mtx_lock(fdip->tick->tk_aw_mtx); 982 983 if (fticket_answered(fdip->tick)) { 984 /* 985 * Just between noticing the interrupt and getting here, 986 * the standard handler has completed his job. 987 * So we drop the ticket and exit as usual. 988 */ 989 SDT_PROBE2(fusefs, , ipc, fdisp_wait_answ_error, 990 "IPC: interrupted, already answered", err); 991 fuse_lck_mtx_unlock(fdip->tick->tk_aw_mtx); 992 goto out; 993 } else { 994 /* 995 * So we were faster than the standard handler. 996 * Then by setting the answered flag we get *him* 997 * to drop the ticket. 998 */ 999 SDT_PROBE2(fusefs, , ipc, fdisp_wait_answ_error, 1000 "IPC: interrupted, setting to answered", err); 1001 fticket_set_answered(fdip->tick); 1002 fuse_lck_mtx_unlock(fdip->tick->tk_aw_mtx); 1003 return err; 1004 } 1005 } 1006 1007 if (fdip->tick->tk_aw_errno == ENOTCONN) { 1008 /* The daemon died while we were waiting for a response */ 1009 err = ENOTCONN; 1010 goto out; 1011 } else if (fdip->tick->tk_aw_errno) { 1012 /* 1013 * There was some sort of communication error with the daemon 1014 * that the client wouldn't understand. 1015 */ 1016 SDT_PROBE2(fusefs, , ipc, fdisp_wait_answ_error, 1017 "IPC: explicit EIO-ing", fdip->tick->tk_aw_errno); 1018 err = EIO; 1019 goto out; 1020 } 1021 if ((err = fdip->tick->tk_aw_ohead.error)) { 1022 SDT_PROBE2(fusefs, , ipc, fdisp_wait_answ_error, 1023 "IPC: setting status", fdip->tick->tk_aw_ohead.error); 1024 /* 1025 * This means a "proper" fuse syscall error. 1026 * We record this value so the caller will 1027 * be able to know it's not a boring messaging 1028 * failure, if she wishes so (and if not, she can 1029 * just simply propagate the return value of this routine). 1030 * [XXX Maybe a bitflag would do the job too, 1031 * if other flags needed, this will be converted thusly.] 1032 */ 1033 fdip->answ_stat = err; 1034 goto out; 1035 } 1036 fdip->answ = fticket_resp(fdip->tick)->base; 1037 fdip->iosize = fticket_resp(fdip->tick)->len; 1038 1039 return 0; 1040 1041 out: 1042 return err; 1043 } 1044 1045 void 1046 fuse_ipc_init(void) 1047 { 1048 ticket_zone = uma_zcreate("fuse_ticket", sizeof(struct fuse_ticket), 1049 fticket_ctor, fticket_dtor, fticket_init, fticket_fini, 1050 UMA_ALIGN_PTR, 0); 1051 fuse_ticket_count = counter_u64_alloc(M_WAITOK); 1052 } 1053 1054 void 1055 fuse_ipc_destroy(void) 1056 { 1057 counter_u64_free(fuse_ticket_count); 1058 uma_zdestroy(ticket_zone); 1059 } 1060 1061 SDT_PROBE_DEFINE3(fusefs,, ipc, warn, "struct fuse_data*", "unsigned", "char*"); 1062 void 1063 fuse_warn(struct fuse_data *data, unsigned flag, const char *msg) 1064 { 1065 SDT_PROBE3(fusefs, , ipc, warn, data, flag, msg); 1066 if (!(data->dataflags & flag)) { 1067 printf("WARNING: FUSE protocol violation for server mounted at " 1068 "%s: %s " 1069 "This warning will not be repeated.\n", 1070 data->mp->mnt_stat.f_mntonname, msg); 1071 data->dataflags |= flag; 1072 } 1073 } 1074