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/cdefs.h> 64 #include <sys/param.h> 65 #include <sys/module.h> 66 #include <sys/systm.h> 67 #include <sys/counter.h> 68 #include <sys/errno.h> 69 #include <sys/kernel.h> 70 #include <sys/conf.h> 71 #include <sys/uio.h> 72 #include <sys/malloc.h> 73 #include <sys/queue.h> 74 #include <sys/lock.h> 75 #include <sys/sx.h> 76 #include <sys/mutex.h> 77 #include <sys/proc.h> 78 #include <sys/mount.h> 79 #include <sys/sdt.h> 80 #include <sys/vnode.h> 81 #include <sys/signalvar.h> 82 #include <sys/syscallsubr.h> 83 #include <sys/sysctl.h> 84 #include <vm/uma.h> 85 86 #include "fuse.h" 87 #include "fuse_node.h" 88 #include "fuse_ipc.h" 89 #include "fuse_internal.h" 90 91 SDT_PROVIDER_DECLARE(fusefs); 92 /* 93 * Fuse trace probe: 94 * arg0: verbosity. Higher numbers give more verbose messages 95 * arg1: Textual message 96 */ 97 SDT_PROBE_DEFINE2(fusefs, , ipc, trace, "int", "char*"); 98 99 static void fdisp_make_pid(struct fuse_dispatcher *fdip, enum fuse_opcode op, 100 struct fuse_data *data, uint64_t nid, pid_t pid, struct ucred *cred); 101 static void fuse_interrupt_send(struct fuse_ticket *otick, int err); 102 static struct fuse_ticket *fticket_alloc(struct fuse_data *data); 103 static void fticket_refresh(struct fuse_ticket *ftick); 104 static inline void fticket_reset(struct fuse_ticket *ftick); 105 static void fticket_destroy(struct fuse_ticket *ftick); 106 static int fticket_wait_answer(struct fuse_ticket *ftick); 107 static inline int 108 fticket_aw_pull_uio(struct fuse_ticket *ftick, 109 struct uio *uio); 110 111 static int fuse_body_audit(struct fuse_ticket *ftick, size_t blen); 112 113 static fuse_handler_t fuse_standard_handler; 114 115 static counter_u64_t fuse_ticket_count; 116 SYSCTL_COUNTER_U64(_vfs_fusefs_stats, OID_AUTO, ticket_count, CTLFLAG_RD, 117 &fuse_ticket_count, "Number of allocated tickets"); 118 119 static long fuse_iov_permanent_bufsize = 1 << 19; 120 121 SYSCTL_LONG(_vfs_fusefs, OID_AUTO, iov_permanent_bufsize, CTLFLAG_RW, 122 &fuse_iov_permanent_bufsize, 0, 123 "limit for permanently stored buffer size for fuse_iovs"); 124 static int fuse_iov_credit = 16; 125 126 SYSCTL_INT(_vfs_fusefs, OID_AUTO, iov_credit, CTLFLAG_RW, 127 &fuse_iov_credit, 0, 128 "how many times is an oversized fuse_iov tolerated"); 129 130 MALLOC_DEFINE(M_FUSEMSG, "fuse_msgbuf", "fuse message buffer"); 131 static uma_zone_t ticket_zone; 132 133 /* 134 * TODO: figure out how to timeout INTERRUPT requests, because the daemon may 135 * leagally never respond 136 */ 137 static int 138 fuse_interrupt_callback(struct fuse_ticket *tick, struct uio *uio) 139 { 140 struct fuse_ticket *otick, *x_tick; 141 struct fuse_interrupt_in *fii; 142 struct fuse_data *data = tick->tk_data; 143 bool found = false; 144 145 fii = (struct fuse_interrupt_in*)((char*)tick->tk_ms_fiov.base + 146 sizeof(struct fuse_in_header)); 147 148 fuse_lck_mtx_lock(data->aw_mtx); 149 TAILQ_FOREACH_SAFE(otick, &data->aw_head, tk_aw_link, x_tick) { 150 if (otick->tk_unique == fii->unique) { 151 found = true; 152 break; 153 } 154 } 155 fuse_lck_mtx_unlock(data->aw_mtx); 156 157 if (!found) { 158 /* Original is already complete. Just return */ 159 return 0; 160 } 161 162 /* Clear the original ticket's interrupt association */ 163 otick->irq_unique = 0; 164 165 if (tick->tk_aw_ohead.error == ENOSYS) { 166 fsess_set_notimpl(data->mp, FUSE_INTERRUPT); 167 return 0; 168 } else if (tick->tk_aw_ohead.error == EAGAIN) { 169 /* 170 * There are two reasons we might get this: 171 * 1) the daemon received the INTERRUPT request before the 172 * original, or 173 * 2) the daemon received the INTERRUPT request after it 174 * completed the original request. 175 * In the first case we should re-send the INTERRUPT. In the 176 * second, we should ignore it. 177 */ 178 /* Resend */ 179 fuse_interrupt_send(otick, EINTR); 180 return 0; 181 } else { 182 /* Illegal FUSE_INTERRUPT response */ 183 return EINVAL; 184 } 185 } 186 187 /* Interrupt the operation otick. Return err as its error code */ 188 void 189 fuse_interrupt_send(struct fuse_ticket *otick, int err) 190 { 191 struct fuse_dispatcher fdi; 192 struct fuse_interrupt_in *fii; 193 struct fuse_in_header *ftick_hdr; 194 struct fuse_data *data = otick->tk_data; 195 struct fuse_ticket *tick, *xtick; 196 struct ucred reused_creds; 197 gid_t reused_groups[1]; 198 199 if (otick->irq_unique == 0) { 200 /* 201 * If the daemon hasn't yet received otick, then we can answer 202 * it ourselves and return. 203 */ 204 fuse_lck_mtx_lock(data->ms_mtx); 205 STAILQ_FOREACH_SAFE(tick, &otick->tk_data->ms_head, tk_ms_link, 206 xtick) { 207 if (tick == otick) { 208 STAILQ_REMOVE(&otick->tk_data->ms_head, tick, 209 fuse_ticket, tk_ms_link); 210 otick->tk_data->ms_count--; 211 otick->tk_ms_link.stqe_next = NULL; 212 fuse_lck_mtx_unlock(data->ms_mtx); 213 214 fuse_lck_mtx_lock(otick->tk_aw_mtx); 215 if (!fticket_answered(otick)) { 216 fticket_set_answered(otick); 217 otick->tk_aw_errno = err; 218 wakeup(otick); 219 } 220 fuse_lck_mtx_unlock(otick->tk_aw_mtx); 221 222 fuse_ticket_drop(tick); 223 return; 224 } 225 } 226 fuse_lck_mtx_unlock(data->ms_mtx); 227 228 /* 229 * If the fuse daemon doesn't support interrupts, then there's 230 * nothing more that we can do 231 */ 232 if (fsess_not_impl(data->mp, FUSE_INTERRUPT)) 233 return; 234 235 /* 236 * If the fuse daemon has already received otick, then we must 237 * send FUSE_INTERRUPT. 238 */ 239 ftick_hdr = fticket_in_header(otick); 240 reused_creds.cr_uid = ftick_hdr->uid; 241 reused_groups[0] = ftick_hdr->gid; 242 reused_creds.cr_groups = reused_groups; 243 fdisp_init(&fdi, sizeof(*fii)); 244 fdisp_make_pid(&fdi, FUSE_INTERRUPT, data, ftick_hdr->nodeid, 245 ftick_hdr->pid, &reused_creds); 246 247 fii = fdi.indata; 248 fii->unique = otick->tk_unique; 249 fuse_insert_callback(fdi.tick, fuse_interrupt_callback); 250 251 otick->irq_unique = fdi.tick->tk_unique; 252 /* Interrupt ops should be delivered ASAP */ 253 fuse_insert_message(fdi.tick, true); 254 fdisp_destroy(&fdi); 255 } else { 256 /* This ticket has already been interrupted */ 257 } 258 } 259 260 void 261 fiov_init(struct fuse_iov *fiov, size_t size) 262 { 263 uint32_t msize = FU_AT_LEAST(size); 264 265 fiov->len = 0; 266 267 fiov->base = malloc(msize, M_FUSEMSG, M_WAITOK | M_ZERO); 268 269 fiov->allocated_size = msize; 270 fiov->credit = fuse_iov_credit; 271 } 272 273 void 274 fiov_teardown(struct fuse_iov *fiov) 275 { 276 MPASS(fiov->base != NULL); 277 free(fiov->base, M_FUSEMSG); 278 } 279 280 void 281 fiov_adjust(struct fuse_iov *fiov, size_t size) 282 { 283 if (fiov->allocated_size < size || 284 (fuse_iov_permanent_bufsize >= 0 && 285 fiov->allocated_size - size > fuse_iov_permanent_bufsize && 286 --fiov->credit < 0)) { 287 fiov->base = realloc(fiov->base, FU_AT_LEAST(size), M_FUSEMSG, 288 M_WAITOK | M_ZERO); 289 if (!fiov->base) { 290 panic("FUSE: realloc failed"); 291 } 292 fiov->allocated_size = FU_AT_LEAST(size); 293 fiov->credit = fuse_iov_credit; 294 /* Clear data buffer after reallocation */ 295 bzero(fiov->base, size); 296 } else if (size > fiov->len) { 297 /* Clear newly extended portion of data buffer */ 298 bzero((char*)fiov->base + fiov->len, size - fiov->len); 299 } 300 fiov->len = size; 301 } 302 303 /* Resize the fiov if needed, and clear it's buffer */ 304 void 305 fiov_refresh(struct fuse_iov *fiov) 306 { 307 fiov_adjust(fiov, 0); 308 } 309 310 static int 311 fticket_ctor(void *mem, int size, void *arg, int flags) 312 { 313 struct fuse_ticket *ftick = mem; 314 struct fuse_data *data = arg; 315 316 FUSE_ASSERT_MS_DONE(ftick); 317 FUSE_ASSERT_AW_DONE(ftick); 318 319 ftick->tk_data = data; 320 ftick->irq_unique = 0; 321 refcount_init(&ftick->tk_refcount, 1); 322 counter_u64_add(fuse_ticket_count, 1); 323 324 fticket_refresh(ftick); 325 326 return 0; 327 } 328 329 static void 330 fticket_dtor(void *mem, int size, void *arg) 331 { 332 #ifdef INVARIANTS 333 struct fuse_ticket *ftick = mem; 334 #endif 335 336 FUSE_ASSERT_MS_DONE(ftick); 337 FUSE_ASSERT_AW_DONE(ftick); 338 339 counter_u64_add(fuse_ticket_count, -1); 340 } 341 342 static int 343 fticket_init(void *mem, int size, int flags) 344 { 345 struct fuse_ticket *ftick = mem; 346 347 bzero(ftick, sizeof(struct fuse_ticket)); 348 349 fiov_init(&ftick->tk_ms_fiov, sizeof(struct fuse_in_header)); 350 351 mtx_init(&ftick->tk_aw_mtx, "fuse answer delivery mutex", NULL, MTX_DEF); 352 fiov_init(&ftick->tk_aw_fiov, 0); 353 354 return 0; 355 } 356 357 static void 358 fticket_fini(void *mem, int size) 359 { 360 struct fuse_ticket *ftick = mem; 361 362 fiov_teardown(&ftick->tk_ms_fiov); 363 fiov_teardown(&ftick->tk_aw_fiov); 364 mtx_destroy(&ftick->tk_aw_mtx); 365 } 366 367 static inline struct fuse_ticket * 368 fticket_alloc(struct fuse_data *data) 369 { 370 return uma_zalloc_arg(ticket_zone, data, M_WAITOK); 371 } 372 373 static inline void 374 fticket_destroy(struct fuse_ticket *ftick) 375 { 376 return uma_zfree(ticket_zone, ftick); 377 } 378 379 /* Prepare the ticket to be reused and clear its data buffers */ 380 static inline void 381 fticket_refresh(struct fuse_ticket *ftick) 382 { 383 fticket_reset(ftick); 384 385 fiov_refresh(&ftick->tk_ms_fiov); 386 fiov_refresh(&ftick->tk_aw_fiov); 387 } 388 389 /* Prepare the ticket to be reused, but don't clear its data buffers */ 390 static inline void 391 fticket_reset(struct fuse_ticket *ftick) 392 { 393 struct fuse_data *data = ftick->tk_data; 394 395 FUSE_ASSERT_MS_DONE(ftick); 396 FUSE_ASSERT_AW_DONE(ftick); 397 398 bzero(&ftick->tk_aw_ohead, sizeof(struct fuse_out_header)); 399 400 ftick->tk_aw_errno = 0; 401 ftick->tk_flag = 0; 402 403 /* May be truncated to 32 bits on LP32 arches */ 404 ftick->tk_unique = atomic_fetchadd_long(&data->ticketer, 1); 405 if (ftick->tk_unique == 0) 406 ftick->tk_unique = atomic_fetchadd_long(&data->ticketer, 1); 407 } 408 409 static int 410 fticket_wait_answer(struct fuse_ticket *ftick) 411 { 412 struct thread *td = curthread; 413 sigset_t blockedset, oldset; 414 int err = 0, stops_deferred; 415 struct fuse_data *data = ftick->tk_data; 416 bool interrupted = false; 417 418 if (fsess_maybe_impl(ftick->tk_data->mp, FUSE_INTERRUPT) && 419 data->dataflags & FSESS_INTR) { 420 SIGEMPTYSET(blockedset); 421 } else { 422 /* Block all signals except (implicitly) SIGKILL */ 423 SIGFILLSET(blockedset); 424 } 425 stops_deferred = sigdeferstop(SIGDEFERSTOP_SILENT); 426 kern_sigprocmask(td, SIG_BLOCK, NULL, &oldset, 0); 427 428 fuse_lck_mtx_lock(ftick->tk_aw_mtx); 429 430 retry: 431 if (fticket_answered(ftick)) { 432 goto out; 433 } 434 435 if (fdata_get_dead(data)) { 436 err = ENOTCONN; 437 fticket_set_answered(ftick); 438 goto out; 439 } 440 kern_sigprocmask(td, SIG_BLOCK, &blockedset, NULL, 0); 441 err = msleep(ftick, &ftick->tk_aw_mtx, PCATCH, "fu_ans", 442 data->daemon_timeout * hz); 443 kern_sigprocmask(td, SIG_SETMASK, &oldset, NULL, 0); 444 if (err == EWOULDBLOCK) { 445 SDT_PROBE2(fusefs, , ipc, trace, 3, 446 "fticket_wait_answer: EWOULDBLOCK"); 447 #ifdef XXXIP /* die conditionally */ 448 if (!fdata_get_dead(data)) { 449 fdata_set_dead(data); 450 } 451 #endif 452 err = ETIMEDOUT; 453 fticket_set_answered(ftick); 454 } else if ((err == EINTR || err == ERESTART)) { 455 /* 456 * Whether we get EINTR or ERESTART depends on whether 457 * SA_RESTART was set by sigaction(2). 458 * 459 * Try to interrupt the operation and wait for an EINTR response 460 * to the original operation. If the file system does not 461 * support FUSE_INTERRUPT, then we'll just wait for it to 462 * complete like normal. If it does support FUSE_INTERRUPT, 463 * then it will either respond EINTR to the original operation, 464 * or EAGAIN to the interrupt. 465 */ 466 sigset_t tmpset; 467 468 SDT_PROBE2(fusefs, , ipc, trace, 4, 469 "fticket_wait_answer: interrupt"); 470 fuse_lck_mtx_unlock(ftick->tk_aw_mtx); 471 fuse_interrupt_send(ftick, err); 472 473 PROC_LOCK(td->td_proc); 474 mtx_lock(&td->td_proc->p_sigacts->ps_mtx); 475 tmpset = td->td_proc->p_siglist; 476 SIGSETOR(tmpset, td->td_siglist); 477 mtx_unlock(&td->td_proc->p_sigacts->ps_mtx); 478 PROC_UNLOCK(td->td_proc); 479 480 fuse_lck_mtx_lock(ftick->tk_aw_mtx); 481 if (!interrupted && !SIGISMEMBER(tmpset, SIGKILL)) { 482 /* 483 * Block all signals while we wait for an interrupt 484 * response. The protocol doesn't discriminate between 485 * different signals. 486 */ 487 SIGFILLSET(blockedset); 488 interrupted = true; 489 goto retry; 490 } else { 491 /* 492 * Return immediately for fatal signals, or if this is 493 * the second interruption. We should only be 494 * interrupted twice if the thread is stopped, for 495 * example during sigexit. 496 */ 497 } 498 } else if (err) { 499 SDT_PROBE2(fusefs, , ipc, trace, 6, 500 "fticket_wait_answer: other error"); 501 } else { 502 SDT_PROBE2(fusefs, , ipc, trace, 7, "fticket_wait_answer: OK"); 503 } 504 out: 505 if (!(err || fticket_answered(ftick))) { 506 SDT_PROBE2(fusefs, , ipc, trace, 1, 507 "FUSE: requester was woken up but still no answer"); 508 err = ENXIO; 509 } 510 fuse_lck_mtx_unlock(ftick->tk_aw_mtx); 511 sigallowstop(stops_deferred); 512 513 return err; 514 } 515 516 static inline 517 int 518 fticket_aw_pull_uio(struct fuse_ticket *ftick, struct uio *uio) 519 { 520 int err = 0; 521 size_t len = uio_resid(uio); 522 523 if (len) { 524 fiov_adjust(fticket_resp(ftick), len); 525 err = uiomove(fticket_resp(ftick)->base, len, uio); 526 } 527 return err; 528 } 529 530 int 531 fticket_pull(struct fuse_ticket *ftick, struct uio *uio) 532 { 533 int err = 0; 534 535 if (ftick->tk_aw_ohead.error) { 536 return 0; 537 } 538 err = fuse_body_audit(ftick, uio_resid(uio)); 539 if (!err) { 540 err = fticket_aw_pull_uio(ftick, uio); 541 } 542 return err; 543 } 544 545 struct fuse_data * 546 fdata_alloc(struct cdev *fdev, struct ucred *cred) 547 { 548 struct fuse_data *data; 549 550 data = malloc(sizeof(struct fuse_data), M_FUSEMSG, M_WAITOK | M_ZERO); 551 552 data->fdev = fdev; 553 mtx_init(&data->ms_mtx, "fuse message list mutex", NULL, MTX_DEF); 554 STAILQ_INIT(&data->ms_head); 555 data->ms_count = 0; 556 knlist_init_mtx(&data->ks_rsel.si_note, &data->ms_mtx); 557 mtx_init(&data->aw_mtx, "fuse answer list mutex", NULL, MTX_DEF); 558 TAILQ_INIT(&data->aw_head); 559 data->daemoncred = crhold(cred); 560 data->daemon_timeout = FUSE_DEFAULT_DAEMON_TIMEOUT; 561 sx_init(&data->rename_lock, "fuse rename lock"); 562 data->ref = 1; 563 564 return data; 565 } 566 567 void 568 fdata_trydestroy(struct fuse_data *data) 569 { 570 data->ref--; 571 MPASS(data->ref >= 0); 572 if (data->ref != 0) 573 return; 574 575 /* Driving off stage all that stuff thrown at device... */ 576 sx_destroy(&data->rename_lock); 577 crfree(data->daemoncred); 578 mtx_destroy(&data->aw_mtx); 579 knlist_delete(&data->ks_rsel.si_note, curthread, 0); 580 knlist_destroy(&data->ks_rsel.si_note); 581 mtx_destroy(&data->ms_mtx); 582 583 free(data, M_FUSEMSG); 584 } 585 586 void 587 fdata_set_dead(struct fuse_data *data) 588 { 589 FUSE_LOCK(); 590 if (fdata_get_dead(data)) { 591 FUSE_UNLOCK(); 592 return; 593 } 594 fuse_lck_mtx_lock(data->ms_mtx); 595 data->dataflags |= FSESS_DEAD; 596 wakeup_one(data); 597 selwakeuppri(&data->ks_rsel, PZERO + 1); 598 wakeup(&data->ticketer); 599 fuse_lck_mtx_unlock(data->ms_mtx); 600 FUSE_UNLOCK(); 601 } 602 603 struct fuse_ticket * 604 fuse_ticket_fetch(struct fuse_data *data) 605 { 606 int err = 0; 607 struct fuse_ticket *ftick; 608 609 ftick = fticket_alloc(data); 610 611 if (!(data->dataflags & FSESS_INITED)) { 612 /* Sleep until get answer for INIT messsage */ 613 FUSE_LOCK(); 614 if (!(data->dataflags & FSESS_INITED) && data->ticketer > 2) { 615 err = msleep(&data->ticketer, &fuse_mtx, PCATCH | PDROP, 616 "fu_ini", 0); 617 if (err) 618 fdata_set_dead(data); 619 } else 620 FUSE_UNLOCK(); 621 } 622 return ftick; 623 } 624 625 int 626 fuse_ticket_drop(struct fuse_ticket *ftick) 627 { 628 int die; 629 630 die = refcount_release(&ftick->tk_refcount); 631 if (die) 632 fticket_destroy(ftick); 633 634 return die; 635 } 636 637 void 638 fuse_insert_callback(struct fuse_ticket *ftick, fuse_handler_t * handler) 639 { 640 if (fdata_get_dead(ftick->tk_data)) { 641 return; 642 } 643 ftick->tk_aw_handler = handler; 644 645 fuse_lck_mtx_lock(ftick->tk_data->aw_mtx); 646 fuse_aw_push(ftick); 647 fuse_lck_mtx_unlock(ftick->tk_data->aw_mtx); 648 } 649 650 /* 651 * Insert a new upgoing ticket into the message queue 652 * 653 * If urgent is true, insert at the front of the queue. Otherwise, insert in 654 * FIFO order. 655 */ 656 void 657 fuse_insert_message(struct fuse_ticket *ftick, bool urgent) 658 { 659 if (ftick->tk_flag & FT_DIRTY) { 660 panic("FUSE: ticket reused without being refreshed"); 661 } 662 ftick->tk_flag |= FT_DIRTY; 663 664 if (fdata_get_dead(ftick->tk_data)) { 665 return; 666 } 667 fuse_lck_mtx_lock(ftick->tk_data->ms_mtx); 668 if (urgent) 669 fuse_ms_push_head(ftick); 670 else 671 fuse_ms_push(ftick); 672 wakeup_one(ftick->tk_data); 673 selwakeuppri(&ftick->tk_data->ks_rsel, PZERO + 1); 674 KNOTE_LOCKED(&ftick->tk_data->ks_rsel.si_note, 0); 675 fuse_lck_mtx_unlock(ftick->tk_data->ms_mtx); 676 } 677 678 static int 679 fuse_body_audit(struct fuse_ticket *ftick, size_t blen) 680 { 681 int err = 0; 682 enum fuse_opcode opcode; 683 684 opcode = fticket_opcode(ftick); 685 686 switch (opcode) { 687 case FUSE_BMAP: 688 err = (blen == sizeof(struct fuse_bmap_out)) ? 0 : EINVAL; 689 break; 690 691 case FUSE_LINK: 692 case FUSE_LOOKUP: 693 case FUSE_MKDIR: 694 case FUSE_MKNOD: 695 case FUSE_SYMLINK: 696 if (fuse_libabi_geq(ftick->tk_data, 7, 9)) { 697 err = (blen == sizeof(struct fuse_entry_out)) ? 698 0 : EINVAL; 699 } else { 700 err = (blen == FUSE_COMPAT_ENTRY_OUT_SIZE) ? 0 : EINVAL; 701 } 702 break; 703 704 case FUSE_FORGET: 705 panic("FUSE: a handler has been intalled for FUSE_FORGET"); 706 break; 707 708 case FUSE_GETATTR: 709 case FUSE_SETATTR: 710 if (fuse_libabi_geq(ftick->tk_data, 7, 9)) { 711 err = (blen == sizeof(struct fuse_attr_out)) ? 712 0 : EINVAL; 713 } else { 714 err = (blen == FUSE_COMPAT_ATTR_OUT_SIZE) ? 0 : EINVAL; 715 } 716 break; 717 718 case FUSE_READLINK: 719 err = (PAGE_SIZE >= blen) ? 0 : EINVAL; 720 break; 721 722 case FUSE_UNLINK: 723 err = (blen == 0) ? 0 : EINVAL; 724 break; 725 726 case FUSE_RMDIR: 727 err = (blen == 0) ? 0 : EINVAL; 728 break; 729 730 case FUSE_RENAME: 731 err = (blen == 0) ? 0 : EINVAL; 732 break; 733 734 case FUSE_OPEN: 735 err = (blen == sizeof(struct fuse_open_out)) ? 0 : EINVAL; 736 break; 737 738 case FUSE_READ: 739 err = (((struct fuse_read_in *)( 740 (char *)ftick->tk_ms_fiov.base + 741 sizeof(struct fuse_in_header) 742 ))->size >= blen) ? 0 : EINVAL; 743 break; 744 745 case FUSE_WRITE: 746 err = (blen == sizeof(struct fuse_write_out)) ? 0 : EINVAL; 747 break; 748 749 case FUSE_STATFS: 750 if (fuse_libabi_geq(ftick->tk_data, 7, 4)) { 751 err = (blen == sizeof(struct fuse_statfs_out)) ? 752 0 : EINVAL; 753 } else { 754 err = (blen == FUSE_COMPAT_STATFS_SIZE) ? 0 : EINVAL; 755 } 756 break; 757 758 case FUSE_RELEASE: 759 err = (blen == 0) ? 0 : EINVAL; 760 break; 761 762 case FUSE_FSYNC: 763 err = (blen == 0) ? 0 : EINVAL; 764 break; 765 766 case FUSE_SETXATTR: 767 err = (blen == 0) ? 0 : EINVAL; 768 break; 769 770 case FUSE_GETXATTR: 771 case FUSE_LISTXATTR: 772 /* 773 * These can have varying response lengths, and 0 length 774 * isn't necessarily invalid. 775 */ 776 err = 0; 777 break; 778 779 case FUSE_REMOVEXATTR: 780 err = (blen == 0) ? 0 : EINVAL; 781 break; 782 783 case FUSE_FLUSH: 784 err = (blen == 0) ? 0 : EINVAL; 785 break; 786 787 case FUSE_INIT: 788 if (blen == sizeof(struct fuse_init_out) || 789 blen == FUSE_COMPAT_INIT_OUT_SIZE || 790 blen == FUSE_COMPAT_22_INIT_OUT_SIZE) { 791 err = 0; 792 } else { 793 err = EINVAL; 794 } 795 break; 796 797 case FUSE_OPENDIR: 798 err = (blen == sizeof(struct fuse_open_out)) ? 0 : EINVAL; 799 break; 800 801 case FUSE_READDIR: 802 err = (((struct fuse_read_in *)( 803 (char *)ftick->tk_ms_fiov.base + 804 sizeof(struct fuse_in_header) 805 ))->size >= blen) ? 0 : EINVAL; 806 break; 807 808 case FUSE_RELEASEDIR: 809 err = (blen == 0) ? 0 : EINVAL; 810 break; 811 812 case FUSE_FSYNCDIR: 813 err = (blen == 0) ? 0 : EINVAL; 814 break; 815 816 case FUSE_GETLK: 817 err = (blen == sizeof(struct fuse_lk_out)) ? 0 : EINVAL; 818 break; 819 820 case FUSE_SETLK: 821 err = (blen == 0) ? 0 : EINVAL; 822 break; 823 824 case FUSE_SETLKW: 825 err = (blen == 0) ? 0 : EINVAL; 826 break; 827 828 case FUSE_ACCESS: 829 err = (blen == 0) ? 0 : EINVAL; 830 break; 831 832 case FUSE_CREATE: 833 if (fuse_libabi_geq(ftick->tk_data, 7, 9)) { 834 err = (blen == sizeof(struct fuse_entry_out) + 835 sizeof(struct fuse_open_out)) ? 0 : EINVAL; 836 } else { 837 err = (blen == FUSE_COMPAT_ENTRY_OUT_SIZE + 838 sizeof(struct fuse_open_out)) ? 0 : EINVAL; 839 } 840 break; 841 842 case FUSE_DESTROY: 843 err = (blen == 0) ? 0 : EINVAL; 844 break; 845 846 case FUSE_FALLOCATE: 847 err = (blen == 0) ? 0 : EINVAL; 848 break; 849 850 case FUSE_LSEEK: 851 err = (blen == sizeof(struct fuse_lseek_out)) ? 0 : EINVAL; 852 break; 853 854 case FUSE_COPY_FILE_RANGE: 855 err = (blen == sizeof(struct fuse_write_out)) ? 0 : EINVAL; 856 break; 857 858 default: 859 panic("FUSE: opcodes out of sync (%d)\n", opcode); 860 } 861 862 return err; 863 } 864 865 static inline void 866 fuse_setup_ihead(struct fuse_in_header *ihead, struct fuse_ticket *ftick, 867 uint64_t nid, enum fuse_opcode op, size_t blen, pid_t pid, 868 struct ucred *cred) 869 { 870 ihead->len = sizeof(*ihead) + blen; 871 ihead->unique = ftick->tk_unique; 872 ihead->nodeid = nid; 873 ihead->opcode = op; 874 875 ihead->pid = pid; 876 ihead->uid = cred->cr_uid; 877 ihead->gid = cred->cr_groups[0]; 878 } 879 880 /* 881 * fuse_standard_handler just pulls indata and wakes up pretender. 882 * Doesn't try to interpret data, that's left for the pretender. 883 * Though might do a basic size verification before the pull-in takes place 884 */ 885 886 static int 887 fuse_standard_handler(struct fuse_ticket *ftick, struct uio *uio) 888 { 889 int err = 0; 890 891 err = fticket_pull(ftick, uio); 892 893 fuse_lck_mtx_lock(ftick->tk_aw_mtx); 894 895 if (!fticket_answered(ftick)) { 896 fticket_set_answered(ftick); 897 ftick->tk_aw_errno = err; 898 wakeup(ftick); 899 } 900 fuse_lck_mtx_unlock(ftick->tk_aw_mtx); 901 902 return err; 903 } 904 905 /* 906 * Reinitialize a dispatcher from a pid and node id, without resizing or 907 * clearing its data buffers 908 */ 909 static void 910 fdisp_refresh_pid(struct fuse_dispatcher *fdip, enum fuse_opcode op, 911 struct mount *mp, uint64_t nid, pid_t pid, struct ucred *cred) 912 { 913 MPASS(fdip->tick); 914 MPASS2(sizeof(fdip->finh) + fdip->iosize <= fdip->tick->tk_ms_fiov.len, 915 "Must use fdisp_make_pid to increase the size of the fiov"); 916 fticket_reset(fdip->tick); 917 918 FUSE_DIMALLOC(&fdip->tick->tk_ms_fiov, fdip->finh, 919 fdip->indata, fdip->iosize); 920 921 fuse_setup_ihead(fdip->finh, fdip->tick, nid, op, fdip->iosize, pid, 922 cred); 923 } 924 925 /* Initialize a dispatcher from a pid and node id */ 926 static void 927 fdisp_make_pid(struct fuse_dispatcher *fdip, enum fuse_opcode op, 928 struct fuse_data *data, uint64_t nid, pid_t pid, struct ucred *cred) 929 { 930 if (fdip->tick) { 931 fticket_refresh(fdip->tick); 932 } else { 933 fdip->tick = fuse_ticket_fetch(data); 934 } 935 936 /* FUSE_DIMALLOC will bzero the fiovs when it enlarges them */ 937 FUSE_DIMALLOC(&fdip->tick->tk_ms_fiov, fdip->finh, 938 fdip->indata, fdip->iosize); 939 940 fuse_setup_ihead(fdip->finh, fdip->tick, nid, op, fdip->iosize, pid, cred); 941 } 942 943 void 944 fdisp_make(struct fuse_dispatcher *fdip, enum fuse_opcode op, struct mount *mp, 945 uint64_t nid, struct thread *td, struct ucred *cred) 946 { 947 struct fuse_data *data = fuse_get_mpdata(mp); 948 RECTIFY_TDCR(td, cred); 949 950 return fdisp_make_pid(fdip, op, data, nid, td->td_proc->p_pid, cred); 951 } 952 953 void 954 fdisp_make_vp(struct fuse_dispatcher *fdip, enum fuse_opcode op, 955 struct vnode *vp, struct thread *td, struct ucred *cred) 956 { 957 struct mount *mp = vnode_mount(vp); 958 struct fuse_data *data = fuse_get_mpdata(mp); 959 960 RECTIFY_TDCR(td, cred); 961 return fdisp_make_pid(fdip, op, data, VTOI(vp), 962 td->td_proc->p_pid, cred); 963 } 964 965 /* Refresh a fuse_dispatcher so it can be reused, but don't zero its data */ 966 void 967 fdisp_refresh_vp(struct fuse_dispatcher *fdip, enum fuse_opcode op, 968 struct vnode *vp, struct thread *td, struct ucred *cred) 969 { 970 RECTIFY_TDCR(td, cred); 971 return fdisp_refresh_pid(fdip, op, vnode_mount(vp), VTOI(vp), 972 td->td_proc->p_pid, cred); 973 } 974 975 SDT_PROBE_DEFINE2(fusefs, , ipc, fdisp_wait_answ_error, "char*", "int"); 976 977 int 978 fdisp_wait_answ(struct fuse_dispatcher *fdip) 979 { 980 int err = 0; 981 982 fdip->answ_stat = 0; 983 fuse_insert_callback(fdip->tick, fuse_standard_handler); 984 fuse_insert_message(fdip->tick, false); 985 986 if ((err = fticket_wait_answer(fdip->tick))) { 987 fuse_lck_mtx_lock(fdip->tick->tk_aw_mtx); 988 989 if (fticket_answered(fdip->tick)) { 990 /* 991 * Just between noticing the interrupt and getting here, 992 * the standard handler has completed his job. 993 * So we drop the ticket and exit as usual. 994 */ 995 SDT_PROBE2(fusefs, , ipc, fdisp_wait_answ_error, 996 "IPC: interrupted, already answered", err); 997 fuse_lck_mtx_unlock(fdip->tick->tk_aw_mtx); 998 goto out; 999 } else { 1000 /* 1001 * So we were faster than the standard handler. 1002 * Then by setting the answered flag we get *him* 1003 * to drop the ticket. 1004 */ 1005 SDT_PROBE2(fusefs, , ipc, fdisp_wait_answ_error, 1006 "IPC: interrupted, setting to answered", err); 1007 fticket_set_answered(fdip->tick); 1008 fuse_lck_mtx_unlock(fdip->tick->tk_aw_mtx); 1009 return err; 1010 } 1011 } 1012 1013 if (fdip->tick->tk_aw_errno == ENOTCONN) { 1014 /* The daemon died while we were waiting for a response */ 1015 err = ENOTCONN; 1016 goto out; 1017 } else if (fdip->tick->tk_aw_errno) { 1018 /* 1019 * There was some sort of communication error with the daemon 1020 * that the client wouldn't understand. 1021 */ 1022 SDT_PROBE2(fusefs, , ipc, fdisp_wait_answ_error, 1023 "IPC: explicit EIO-ing", fdip->tick->tk_aw_errno); 1024 err = EIO; 1025 goto out; 1026 } 1027 if ((err = fdip->tick->tk_aw_ohead.error)) { 1028 SDT_PROBE2(fusefs, , ipc, fdisp_wait_answ_error, 1029 "IPC: setting status", fdip->tick->tk_aw_ohead.error); 1030 /* 1031 * This means a "proper" fuse syscall error. 1032 * We record this value so the caller will 1033 * be able to know it's not a boring messaging 1034 * failure, if she wishes so (and if not, she can 1035 * just simply propagate the return value of this routine). 1036 * [XXX Maybe a bitflag would do the job too, 1037 * if other flags needed, this will be converted thusly.] 1038 */ 1039 fdip->answ_stat = err; 1040 goto out; 1041 } 1042 fdip->answ = fticket_resp(fdip->tick)->base; 1043 fdip->iosize = fticket_resp(fdip->tick)->len; 1044 1045 return 0; 1046 1047 out: 1048 return err; 1049 } 1050 1051 void 1052 fuse_ipc_init(void) 1053 { 1054 ticket_zone = uma_zcreate("fuse_ticket", sizeof(struct fuse_ticket), 1055 fticket_ctor, fticket_dtor, fticket_init, fticket_fini, 1056 UMA_ALIGN_PTR, 0); 1057 fuse_ticket_count = counter_u64_alloc(M_WAITOK); 1058 } 1059 1060 void 1061 fuse_ipc_destroy(void) 1062 { 1063 counter_u64_free(fuse_ticket_count); 1064 uma_zdestroy(ticket_zone); 1065 } 1066 1067 SDT_PROBE_DEFINE3(fusefs,, ipc, warn, "struct fuse_data*", "unsigned", "char*"); 1068 void 1069 fuse_warn(struct fuse_data *data, unsigned flag, const char *msg) 1070 { 1071 SDT_PROBE3(fusefs, , ipc, warn, data, flag, msg); 1072 if (!(data->dataflags & flag)) { 1073 printf("WARNING: FUSE protocol violation for server mounted at " 1074 "%s: %s " 1075 "This warning will not be repeated.\n", 1076 data->mp->mnt_stat.f_mntonname, msg); 1077 data->dataflags |= flag; 1078 } 1079 } 1080