Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
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FreeBSD/Linux Kernel Cross Reference
sys/fs/fuse/fuse_ipc.c
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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 __FBSDID("$FreeBSD$"); 65 66 #include <sys/param.h> 67 #include <sys/module.h> 68 #include <sys/systm.h> 69 #include <sys/counter.h> 70 #include <sys/errno.h> 71 #include <sys/kernel.h> 72 #include <sys/conf.h> 73 #include <sys/uio.h> 74 #include <sys/malloc.h> 75 #include <sys/queue.h> 76 #include <sys/lock.h> 77 #include <sys/sx.h> 78 #include <sys/mutex.h> 79 #include <sys/proc.h> 80 #include <sys/mount.h> 81 #include <sys/sdt.h> 82 #include <sys/vnode.h> 83 #include <sys/signalvar.h> 84 #include <sys/syscallsubr.h> 85 #include <sys/sysctl.h> 86 #include <vm/uma.h> 87 88 #include "fuse.h" 89 #include "fuse_node.h" 90 #include "fuse_ipc.h" 91 #include "fuse_internal.h" 92 93 SDT_PROVIDER_DECLARE(fusefs); 94 /* 95 * Fuse trace probe: 96 * arg0: verbosity. Higher numbers give more verbose messages 97 * arg1: Textual message 98 */ 99 SDT_PROBE_DEFINE2(fusefs, , ipc, trace, "int", "char*"); 100 101 static void fdisp_make_pid(struct fuse_dispatcher *fdip, enum fuse_opcode op, 102 struct fuse_data *data, uint64_t nid, pid_t pid, struct ucred *cred); 103 static void fuse_interrupt_send(struct fuse_ticket *otick, int err); 104 static struct fuse_ticket *fticket_alloc(struct fuse_data *data); 105 static void fticket_refresh(struct fuse_ticket *ftick); 106 static inline void fticket_reset(struct fuse_ticket *ftick); 107 static void fticket_destroy(struct fuse_ticket *ftick); 108 static int fticket_wait_answer(struct fuse_ticket *ftick); 109 static inline int 110 fticket_aw_pull_uio(struct fuse_ticket *ftick, 111 struct uio *uio); 112 113 static int fuse_body_audit(struct fuse_ticket *ftick, size_t blen); 114 115 static fuse_handler_t fuse_standard_handler; 116 117 static counter_u64_t fuse_ticket_count; 118 SYSCTL_COUNTER_U64(_vfs_fusefs_stats, OID_AUTO, ticket_count, CTLFLAG_RD, 119 &fuse_ticket_count, "Number of allocated tickets"); 120 121 static long fuse_iov_permanent_bufsize = 1 << 19; 122 123 SYSCTL_LONG(_vfs_fusefs, OID_AUTO, iov_permanent_bufsize, CTLFLAG_RW, 124 &fuse_iov_permanent_bufsize, 0, 125 "limit for permanently stored buffer size for fuse_iovs"); 126 static int fuse_iov_credit = 16; 127 128 SYSCTL_INT(_vfs_fusefs, OID_AUTO, iov_credit, CTLFLAG_RW, 129 &fuse_iov_credit, 0, 130 "how many times is an oversized fuse_iov tolerated"); 131 132 MALLOC_DEFINE(M_FUSEMSG, "fuse_msgbuf", "fuse message buffer"); 133 static uma_zone_t ticket_zone; 134 135 /* 136 * TODO: figure out how to timeout INTERRUPT requests, because the daemon may 137 * leagally never respond 138 */ 139 static int 140 fuse_interrupt_callback(struct fuse_ticket *tick, struct uio *uio) 141 { 142 struct fuse_ticket *otick, *x_tick; 143 struct fuse_interrupt_in *fii; 144 struct fuse_data *data = tick->tk_data; 145 bool found = false; 146 147 fii = (struct fuse_interrupt_in*)((char*)tick->tk_ms_fiov.base + 148 sizeof(struct fuse_in_header)); 149 150 fuse_lck_mtx_lock(data->aw_mtx); 151 TAILQ_FOREACH_SAFE(otick, &data->aw_head, tk_aw_link, x_tick) { 152 if (otick->tk_unique == fii->unique) { 153 found = true; 154 break; 155 } 156 } 157 fuse_lck_mtx_unlock(data->aw_mtx); 158 159 if (!found) { 160 /* Original is already complete. Just return */ 161 return 0; 162 } 163 164 /* Clear the original ticket's interrupt association */ 165 otick->irq_unique = 0; 166 167 if (tick->tk_aw_ohead.error == ENOSYS) { 168 fsess_set_notimpl(data->mp, FUSE_INTERRUPT); 169 return 0; 170 } else if (tick->tk_aw_ohead.error == EAGAIN) { 171 /* 172 * There are two reasons we might get this: 173 * 1) the daemon received the INTERRUPT request before the 174 * original, or 175 * 2) the daemon received the INTERRUPT request after it 176 * completed the original request. 177 * In the first case we should re-send the INTERRUPT. In the 178 * second, we should ignore it. 179 */ 180 /* Resend */ 181 fuse_interrupt_send(otick, EINTR); 182 return 0; 183 } else { 184 /* Illegal FUSE_INTERRUPT response */ 185 return EINVAL; 186 } 187 } 188 189 /* Interrupt the operation otick. Return err as its error code */ 190 void 191 fuse_interrupt_send(struct fuse_ticket *otick, int err) 192 { 193 struct fuse_dispatcher fdi; 194 struct fuse_interrupt_in *fii; 195 struct fuse_in_header *ftick_hdr; 196 struct fuse_data *data = otick->tk_data; 197 struct fuse_ticket *tick, *xtick; 198 struct ucred reused_creds; 199 gid_t reused_groups[1]; 200 201 if (otick->irq_unique == 0) { 202 /* 203 * If the daemon hasn't yet received otick, then we can answer 204 * it ourselves and return. 205 */ 206 fuse_lck_mtx_lock(data->ms_mtx); 207 STAILQ_FOREACH_SAFE(tick, &otick->tk_data->ms_head, tk_ms_link, 208 xtick) { 209 if (tick == otick) { 210 STAILQ_REMOVE(&otick->tk_data->ms_head, tick, 211 fuse_ticket, tk_ms_link); 212 otick->tk_data->ms_count--; 213 otick->tk_ms_link.stqe_next = NULL; 214 fuse_lck_mtx_unlock(data->ms_mtx); 215 216 fuse_lck_mtx_lock(otick->tk_aw_mtx); 217 if (!fticket_answered(otick)) { 218 fticket_set_answered(otick); 219 otick->tk_aw_errno = err; 220 wakeup(otick); 221 } 222 fuse_lck_mtx_unlock(otick->tk_aw_mtx); 223 224 fuse_ticket_drop(tick); 225 return; 226 } 227 } 228 fuse_lck_mtx_unlock(data->ms_mtx); 229 230 /* 231 * If the fuse daemon doesn't support interrupts, then there's 232 * nothing more that we can do 233 */ 234 if (!fsess_isimpl(data->mp, FUSE_INTERRUPT)) 235 return; 236 237 /* 238 * If the fuse daemon has already received otick, then we must 239 * send FUSE_INTERRUPT. 240 */ 241 ftick_hdr = fticket_in_header(otick); 242 reused_creds.cr_uid = ftick_hdr->uid; 243 reused_groups[0] = ftick_hdr->gid; 244 reused_creds.cr_groups = reused_groups; 245 fdisp_init(&fdi, sizeof(*fii)); 246 fdisp_make_pid(&fdi, FUSE_INTERRUPT, data, ftick_hdr->nodeid, 247 ftick_hdr->pid, &reused_creds); 248 249 fii = fdi.indata; 250 fii->unique = otick->tk_unique; 251 fuse_insert_callback(fdi.tick, fuse_interrupt_callback); 252 253 otick->irq_unique = fdi.tick->tk_unique; 254 /* Interrupt ops should be delivered ASAP */ 255 fuse_insert_message(fdi.tick, true); 256 fdisp_destroy(&fdi); 257 } else { 258 /* This ticket has already been interrupted */ 259 } 260 } 261 262 void 263 fiov_init(struct fuse_iov *fiov, size_t size) 264 { 265 uint32_t msize = FU_AT_LEAST(size); 266 267 fiov->len = 0; 268 269 fiov->base = malloc(msize, M_FUSEMSG, M_WAITOK | M_ZERO); 270 271 fiov->allocated_size = msize; 272 fiov->credit = fuse_iov_credit; 273 } 274 275 void 276 fiov_teardown(struct fuse_iov *fiov) 277 { 278 MPASS(fiov->base != NULL); 279 free(fiov->base, M_FUSEMSG); 280 } 281 282 void 283 fiov_adjust(struct fuse_iov *fiov, size_t size) 284 { 285 if (fiov->allocated_size < size || 286 (fuse_iov_permanent_bufsize >= 0 && 287 fiov->allocated_size - size > fuse_iov_permanent_bufsize && 288 --fiov->credit < 0)) { 289 290 fiov->base = realloc(fiov->base, FU_AT_LEAST(size), M_FUSEMSG, 291 M_WAITOK | M_ZERO); 292 if (!fiov->base) { 293 panic("FUSE: realloc failed"); 294 } 295 fiov->allocated_size = FU_AT_LEAST(size); 296 fiov->credit = fuse_iov_credit; 297 /* Clear data buffer after reallocation */ 298 bzero(fiov->base, size); 299 } else if (size > fiov->len) { 300 /* Clear newly extended portion of data buffer */ 301 bzero((char*)fiov->base + fiov->len, size - fiov->len); 302 } 303 fiov->len = size; 304 } 305 306 /* Resize the fiov if needed, and clear it's buffer */ 307 void 308 fiov_refresh(struct fuse_iov *fiov) 309 { 310 fiov_adjust(fiov, 0); 311 } 312 313 static int 314 fticket_ctor(void *mem, int size, void *arg, int flags) 315 { 316 struct fuse_ticket *ftick = mem; 317 struct fuse_data *data = arg; 318 319 FUSE_ASSERT_MS_DONE(ftick); 320 FUSE_ASSERT_AW_DONE(ftick); 321 322 ftick->tk_data = data; 323 ftick->irq_unique = 0; 324 refcount_init(&ftick->tk_refcount, 1); 325 counter_u64_add(fuse_ticket_count, 1); 326 327 fticket_refresh(ftick); 328 329 return 0; 330 } 331 332 static void 333 fticket_dtor(void *mem, int size, void *arg) 334 { 335 #ifdef INVARIANTS 336 struct fuse_ticket *ftick = mem; 337 #endif 338 339 FUSE_ASSERT_MS_DONE(ftick); 340 FUSE_ASSERT_AW_DONE(ftick); 341 342 counter_u64_add(fuse_ticket_count, -1); 343 } 344 345 static int 346 fticket_init(void *mem, int size, int flags) 347 { 348 struct fuse_ticket *ftick = mem; 349 350 bzero(ftick, sizeof(struct fuse_ticket)); 351 352 fiov_init(&ftick->tk_ms_fiov, sizeof(struct fuse_in_header)); 353 354 mtx_init(&ftick->tk_aw_mtx, "fuse answer delivery mutex", NULL, MTX_DEF); 355 fiov_init(&ftick->tk_aw_fiov, 0); 356 357 return 0; 358 } 359 360 static void 361 fticket_fini(void *mem, int size) 362 { 363 struct fuse_ticket *ftick = mem; 364 365 fiov_teardown(&ftick->tk_ms_fiov); 366 fiov_teardown(&ftick->tk_aw_fiov); 367 mtx_destroy(&ftick->tk_aw_mtx); 368 } 369 370 static inline struct fuse_ticket * 371 fticket_alloc(struct fuse_data *data) 372 { 373 return uma_zalloc_arg(ticket_zone, data, M_WAITOK); 374 } 375 376 static inline void 377 fticket_destroy(struct fuse_ticket *ftick) 378 { 379 return uma_zfree(ticket_zone, ftick); 380 } 381 382 /* Prepare the ticket to be reused and clear its data buffers */ 383 static inline void 384 fticket_refresh(struct fuse_ticket *ftick) 385 { 386 fticket_reset(ftick); 387 388 fiov_refresh(&ftick->tk_ms_fiov); 389 fiov_refresh(&ftick->tk_aw_fiov); 390 } 391 392 /* Prepare the ticket to be reused, but don't clear its data buffers */ 393 static inline void 394 fticket_reset(struct fuse_ticket *ftick) 395 { 396 struct fuse_data *data = ftick->tk_data; 397 398 FUSE_ASSERT_MS_DONE(ftick); 399 FUSE_ASSERT_AW_DONE(ftick); 400 401 bzero(&ftick->tk_aw_ohead, sizeof(struct fuse_out_header)); 402 403 ftick->tk_aw_errno = 0; 404 ftick->tk_flag = 0; 405 406 /* May be truncated to 32 bits on LP32 arches */ 407 ftick->tk_unique = atomic_fetchadd_long(&data->ticketer, 1); 408 if (ftick->tk_unique == 0) 409 ftick->tk_unique = atomic_fetchadd_long(&data->ticketer, 1); 410 } 411 412 static int 413 fticket_wait_answer(struct fuse_ticket *ftick) 414 { 415 struct thread *td = curthread; 416 sigset_t blockedset, oldset; 417 int err = 0, stops_deferred; 418 struct fuse_data *data = ftick->tk_data; 419 bool interrupted = false; 420 421 if (fsess_isimpl(ftick->tk_data->mp, FUSE_INTERRUPT) && 422 data->dataflags & FSESS_INTR) { 423 SIGEMPTYSET(blockedset); 424 } else { 425 /* Block all signals except (implicitly) SIGKILL */ 426 SIGFILLSET(blockedset); 427 } 428 stops_deferred = sigdeferstop(SIGDEFERSTOP_SILENT); 429 kern_sigprocmask(td, SIG_BLOCK, NULL, &oldset, 0); 430 431 fuse_lck_mtx_lock(ftick->tk_aw_mtx); 432 433 retry: 434 if (fticket_answered(ftick)) { 435 goto out; 436 } 437 438 if (fdata_get_dead(data)) { 439 err = ENOTCONN; 440 fticket_set_answered(ftick); 441 goto out; 442 } 443 kern_sigprocmask(td, SIG_BLOCK, &blockedset, NULL, 0); 444 err = msleep(ftick, &ftick->tk_aw_mtx, PCATCH, "fu_ans", 445 data->daemon_timeout * hz); 446 kern_sigprocmask(td, SIG_SETMASK, &oldset, NULL, 0); 447 if (err == EWOULDBLOCK) { 448 SDT_PROBE2(fusefs, , ipc, trace, 3, 449 "fticket_wait_answer: EWOULDBLOCK"); 450 #ifdef XXXIP /* die conditionally */ 451 if (!fdata_get_dead(data)) { 452 fdata_set_dead(data); 453 } 454 #endif 455 err = ETIMEDOUT; 456 fticket_set_answered(ftick); 457 } else if ((err == EINTR || err == ERESTART)) { 458 /* 459 * Whether we get EINTR or ERESTART depends on whether 460 * SA_RESTART was set by sigaction(2). 461 * 462 * Try to interrupt the operation and wait for an EINTR response 463 * to the original operation. If the file system does not 464 * support FUSE_INTERRUPT, then we'll just wait for it to 465 * complete like normal. If it does support FUSE_INTERRUPT, 466 * then it will either respond EINTR to the original operation, 467 * or EAGAIN to the interrupt. 468 */ 469 sigset_t tmpset; 470 471 SDT_PROBE2(fusefs, , ipc, trace, 4, 472 "fticket_wait_answer: interrupt"); 473 fuse_lck_mtx_unlock(ftick->tk_aw_mtx); 474 fuse_interrupt_send(ftick, err); 475 476 PROC_LOCK(td->td_proc); 477 mtx_lock(&td->td_proc->p_sigacts->ps_mtx); 478 tmpset = td->td_proc->p_siglist; 479 SIGSETOR(tmpset, td->td_siglist); 480 mtx_unlock(&td->td_proc->p_sigacts->ps_mtx); 481 PROC_UNLOCK(td->td_proc); 482 483 fuse_lck_mtx_lock(ftick->tk_aw_mtx); 484 if (!interrupted && !SIGISMEMBER(tmpset, SIGKILL)) { 485 /* 486 * Block all signals while we wait for an interrupt 487 * response. The protocol doesn't discriminate between 488 * different signals. 489 */ 490 SIGFILLSET(blockedset); 491 interrupted = true; 492 goto retry; 493 } else { 494 /* 495 * Return immediately for fatal signals, or if this is 496 * the second interruption. We should only be 497 * interrupted twice if the thread is stopped, for 498 * example during sigexit. 499 */ 500 } 501 } else if (err) { 502 SDT_PROBE2(fusefs, , ipc, trace, 6, 503 "fticket_wait_answer: other error"); 504 } else { 505 SDT_PROBE2(fusefs, , ipc, trace, 7, "fticket_wait_answer: OK"); 506 } 507 out: 508 if (!(err || fticket_answered(ftick))) { 509 SDT_PROBE2(fusefs, , ipc, trace, 1, 510 "FUSE: requester was woken up but still no answer"); 511 err = ENXIO; 512 } 513 fuse_lck_mtx_unlock(ftick->tk_aw_mtx); 514 sigallowstop(stops_deferred); 515 516 return err; 517 } 518 519 static inline 520 int 521 fticket_aw_pull_uio(struct fuse_ticket *ftick, struct uio *uio) 522 { 523 int err = 0; 524 size_t len = uio_resid(uio); 525 526 if (len) { 527 fiov_adjust(fticket_resp(ftick), len); 528 err = uiomove(fticket_resp(ftick)->base, len, uio); 529 } 530 return err; 531 } 532 533 int 534 fticket_pull(struct fuse_ticket *ftick, struct uio *uio) 535 { 536 int err = 0; 537 538 if (ftick->tk_aw_ohead.error) { 539 return 0; 540 } 541 err = fuse_body_audit(ftick, uio_resid(uio)); 542 if (!err) { 543 err = fticket_aw_pull_uio(ftick, uio); 544 } 545 return err; 546 } 547 548 struct fuse_data * 549 fdata_alloc(struct cdev *fdev, struct ucred *cred) 550 { 551 struct fuse_data *data; 552 553 data = malloc(sizeof(struct fuse_data), M_FUSEMSG, M_WAITOK | M_ZERO); 554 555 data->fdev = fdev; 556 mtx_init(&data->ms_mtx, "fuse message list mutex", NULL, MTX_DEF); 557 STAILQ_INIT(&data->ms_head); 558 data->ms_count = 0; 559 knlist_init_mtx(&data->ks_rsel.si_note, &data->ms_mtx); 560 mtx_init(&data->aw_mtx, "fuse answer list mutex", NULL, MTX_DEF); 561 TAILQ_INIT(&data->aw_head); 562 data->daemoncred = crhold(cred); 563 data->daemon_timeout = FUSE_DEFAULT_DAEMON_TIMEOUT; 564 sx_init(&data->rename_lock, "fuse rename lock"); 565 data->ref = 1; 566 567 return data; 568 } 569 570 void 571 fdata_trydestroy(struct fuse_data *data) 572 { 573 data->ref--; 574 MPASS(data->ref >= 0); 575 if (data->ref != 0) 576 return; 577 578 /* Driving off stage all that stuff thrown at device... */ 579 sx_destroy(&data->rename_lock); 580 crfree(data->daemoncred); 581 mtx_destroy(&data->aw_mtx); 582 knlist_delete(&data->ks_rsel.si_note, curthread, 0); 583 knlist_destroy(&data->ks_rsel.si_note); 584 mtx_destroy(&data->ms_mtx); 585 586 free(data, M_FUSEMSG); 587 } 588 589 void 590 fdata_set_dead(struct fuse_data *data) 591 { 592 FUSE_LOCK(); 593 if (fdata_get_dead(data)) { 594 FUSE_UNLOCK(); 595 return; 596 } 597 fuse_lck_mtx_lock(data->ms_mtx); 598 data->dataflags |= FSESS_DEAD; 599 wakeup_one(data); 600 selwakeuppri(&data->ks_rsel, PZERO + 1); 601 wakeup(&data->ticketer); 602 fuse_lck_mtx_unlock(data->ms_mtx); 603 FUSE_UNLOCK(); 604 } 605 606 struct fuse_ticket * 607 fuse_ticket_fetch(struct fuse_data *data) 608 { 609 int err = 0; 610 struct fuse_ticket *ftick; 611 612 ftick = fticket_alloc(data); 613 614 if (!(data->dataflags & FSESS_INITED)) { 615 /* Sleep until get answer for INIT messsage */ 616 FUSE_LOCK(); 617 if (!(data->dataflags & FSESS_INITED) && data->ticketer > 2) { 618 err = msleep(&data->ticketer, &fuse_mtx, PCATCH | PDROP, 619 "fu_ini", 0); 620 if (err) 621 fdata_set_dead(data); 622 } else 623 FUSE_UNLOCK(); 624 } 625 return ftick; 626 } 627 628 int 629 fuse_ticket_drop(struct fuse_ticket *ftick) 630 { 631 int die; 632 633 die = refcount_release(&ftick->tk_refcount); 634 if (die) 635 fticket_destroy(ftick); 636 637 return die; 638 } 639 640 void 641 fuse_insert_callback(struct fuse_ticket *ftick, fuse_handler_t * handler) 642 { 643 if (fdata_get_dead(ftick->tk_data)) { 644 return; 645 } 646 ftick->tk_aw_handler = handler; 647 648 fuse_lck_mtx_lock(ftick->tk_data->aw_mtx); 649 fuse_aw_push(ftick); 650 fuse_lck_mtx_unlock(ftick->tk_data->aw_mtx); 651 } 652 653 /* 654 * Insert a new upgoing ticket into the message queue 655 * 656 * If urgent is true, insert at the front of the queue. Otherwise, insert in 657 * FIFO order. 658 */ 659 void 660 fuse_insert_message(struct fuse_ticket *ftick, bool urgent) 661 { 662 if (ftick->tk_flag & FT_DIRTY) { 663 panic("FUSE: ticket reused without being refreshed"); 664 } 665 ftick->tk_flag |= FT_DIRTY; 666 667 if (fdata_get_dead(ftick->tk_data)) { 668 return; 669 } 670 fuse_lck_mtx_lock(ftick->tk_data->ms_mtx); 671 if (urgent) 672 fuse_ms_push_head(ftick); 673 else 674 fuse_ms_push(ftick); 675 wakeup_one(ftick->tk_data); 676 selwakeuppri(&ftick->tk_data->ks_rsel, PZERO + 1); 677 KNOTE_LOCKED(&ftick->tk_data->ks_rsel.si_note, 0); 678 fuse_lck_mtx_unlock(ftick->tk_data->ms_mtx); 679 } 680 681 static int 682 fuse_body_audit(struct fuse_ticket *ftick, size_t blen) 683 { 684 int err = 0; 685 enum fuse_opcode opcode; 686 687 opcode = fticket_opcode(ftick); 688 689 switch (opcode) { 690 case FUSE_BMAP: 691 err = (blen == sizeof(struct fuse_bmap_out)) ? 0 : EINVAL; 692 break; 693 694 case FUSE_LINK: 695 case FUSE_LOOKUP: 696 case FUSE_MKDIR: 697 case FUSE_MKNOD: 698 case FUSE_SYMLINK: 699 if (fuse_libabi_geq(ftick->tk_data, 7, 9)) { 700 err = (blen == sizeof(struct fuse_entry_out)) ? 701 0 : EINVAL; 702 } else { 703 err = (blen == FUSE_COMPAT_ENTRY_OUT_SIZE) ? 0 : EINVAL; 704 } 705 break; 706 707 case FUSE_FORGET: 708 panic("FUSE: a handler has been intalled for FUSE_FORGET"); 709 break; 710 711 case FUSE_GETATTR: 712 case FUSE_SETATTR: 713 if (fuse_libabi_geq(ftick->tk_data, 7, 9)) { 714 err = (blen == sizeof(struct fuse_attr_out)) ? 715 0 : EINVAL; 716 } else { 717 err = (blen == FUSE_COMPAT_ATTR_OUT_SIZE) ? 0 : EINVAL; 718 } 719 break; 720 721 case FUSE_READLINK: 722 err = (PAGE_SIZE >= blen) ? 0 : EINVAL; 723 break; 724 725 case FUSE_UNLINK: 726 err = (blen == 0) ? 0 : EINVAL; 727 break; 728 729 case FUSE_RMDIR: 730 err = (blen == 0) ? 0 : EINVAL; 731 break; 732 733 case FUSE_RENAME: 734 err = (blen == 0) ? 0 : EINVAL; 735 break; 736 737 case FUSE_OPEN: 738 err = (blen == sizeof(struct fuse_open_out)) ? 0 : EINVAL; 739 break; 740 741 case FUSE_READ: 742 err = (((struct fuse_read_in *)( 743 (char *)ftick->tk_ms_fiov.base + 744 sizeof(struct fuse_in_header) 745 ))->size >= blen) ? 0 : EINVAL; 746 break; 747 748 case FUSE_WRITE: 749 err = (blen == sizeof(struct fuse_write_out)) ? 0 : EINVAL; 750 break; 751 752 case FUSE_STATFS: 753 if (fuse_libabi_geq(ftick->tk_data, 7, 4)) { 754 err = (blen == sizeof(struct fuse_statfs_out)) ? 755 0 : EINVAL; 756 } else { 757 err = (blen == FUSE_COMPAT_STATFS_SIZE) ? 0 : EINVAL; 758 } 759 break; 760 761 case FUSE_RELEASE: 762 err = (blen == 0) ? 0 : EINVAL; 763 break; 764 765 case FUSE_FSYNC: 766 err = (blen == 0) ? 0 : EINVAL; 767 break; 768 769 case FUSE_SETXATTR: 770 err = (blen == 0) ? 0 : EINVAL; 771 break; 772 773 case FUSE_GETXATTR: 774 case FUSE_LISTXATTR: 775 /* 776 * These can have varying response lengths, and 0 length 777 * isn't necessarily invalid. 778 */ 779 err = 0; 780 break; 781 782 case FUSE_REMOVEXATTR: 783 err = (blen == 0) ? 0 : EINVAL; 784 break; 785 786 case FUSE_FLUSH: 787 err = (blen == 0) ? 0 : EINVAL; 788 break; 789 790 case FUSE_INIT: 791 if (blen == sizeof(struct fuse_init_out) || 792 blen == FUSE_COMPAT_INIT_OUT_SIZE || 793 blen == FUSE_COMPAT_22_INIT_OUT_SIZE) { 794 err = 0; 795 } else { 796 err = EINVAL; 797 } 798 break; 799 800 case FUSE_OPENDIR: 801 err = (blen == sizeof(struct fuse_open_out)) ? 0 : EINVAL; 802 break; 803 804 case FUSE_READDIR: 805 err = (((struct fuse_read_in *)( 806 (char *)ftick->tk_ms_fiov.base + 807 sizeof(struct fuse_in_header) 808 ))->size >= blen) ? 0 : EINVAL; 809 break; 810 811 case FUSE_RELEASEDIR: 812 err = (blen == 0) ? 0 : EINVAL; 813 break; 814 815 case FUSE_FSYNCDIR: 816 err = (blen == 0) ? 0 : EINVAL; 817 break; 818 819 case FUSE_GETLK: 820 err = (blen == sizeof(struct fuse_lk_out)) ? 0 : EINVAL; 821 break; 822 823 case FUSE_SETLK: 824 err = (blen == 0) ? 0 : EINVAL; 825 break; 826 827 case FUSE_SETLKW: 828 err = (blen == 0) ? 0 : EINVAL; 829 break; 830 831 case FUSE_ACCESS: 832 err = (blen == 0) ? 0 : EINVAL; 833 break; 834 835 case FUSE_CREATE: 836 if (fuse_libabi_geq(ftick->tk_data, 7, 9)) { 837 err = (blen == sizeof(struct fuse_entry_out) + 838 sizeof(struct fuse_open_out)) ? 0 : EINVAL; 839 } else { 840 err = (blen == FUSE_COMPAT_ENTRY_OUT_SIZE + 841 sizeof(struct fuse_open_out)) ? 0 : EINVAL; 842 } 843 break; 844 845 case FUSE_DESTROY: 846 err = (blen == 0) ? 0 : EINVAL; 847 break; 848 849 default: 850 panic("FUSE: opcodes out of sync (%d)\n", opcode); 851 } 852 853 return err; 854 } 855 856 static inline void 857 fuse_setup_ihead(struct fuse_in_header *ihead, struct fuse_ticket *ftick, 858 uint64_t nid, enum fuse_opcode op, size_t blen, pid_t pid, 859 struct ucred *cred) 860 { 861 ihead->len = sizeof(*ihead) + blen; 862 ihead->unique = ftick->tk_unique; 863 ihead->nodeid = nid; 864 ihead->opcode = op; 865 866 ihead->pid = pid; 867 ihead->uid = cred->cr_uid; 868 ihead->gid = cred->cr_groups[0]; 869 } 870 871 /* 872 * fuse_standard_handler just pulls indata and wakes up pretender. 873 * Doesn't try to interpret data, that's left for the pretender. 874 * Though might do a basic size verification before the pull-in takes place 875 */ 876 877 static int 878 fuse_standard_handler(struct fuse_ticket *ftick, struct uio *uio) 879 { 880 int err = 0; 881 882 err = fticket_pull(ftick, uio); 883 884 fuse_lck_mtx_lock(ftick->tk_aw_mtx); 885 886 if (!fticket_answered(ftick)) { 887 fticket_set_answered(ftick); 888 ftick->tk_aw_errno = err; 889 wakeup(ftick); 890 } 891 fuse_lck_mtx_unlock(ftick->tk_aw_mtx); 892 893 return err; 894 } 895 896 /* 897 * Reinitialize a dispatcher from a pid and node id, without resizing or 898 * clearing its data buffers 899 */ 900 static void 901 fdisp_refresh_pid(struct fuse_dispatcher *fdip, enum fuse_opcode op, 902 struct mount *mp, uint64_t nid, pid_t pid, struct ucred *cred) 903 { 904 MPASS(fdip->tick); 905 MPASS2(sizeof(fdip->finh) + fdip->iosize <= fdip->tick->tk_ms_fiov.len, 906 "Must use fdisp_make_pid to increase the size of the fiov"); 907 fticket_reset(fdip->tick); 908 909 FUSE_DIMALLOC(&fdip->tick->tk_ms_fiov, fdip->finh, 910 fdip->indata, fdip->iosize); 911 912 fuse_setup_ihead(fdip->finh, fdip->tick, nid, op, fdip->iosize, pid, 913 cred); 914 } 915 916 /* Initialize a dispatcher from a pid and node id */ 917 static void 918 fdisp_make_pid(struct fuse_dispatcher *fdip, enum fuse_opcode op, 919 struct fuse_data *data, uint64_t nid, pid_t pid, struct ucred *cred) 920 { 921 if (fdip->tick) { 922 fticket_refresh(fdip->tick); 923 } else { 924 fdip->tick = fuse_ticket_fetch(data); 925 } 926 927 /* FUSE_DIMALLOC will bzero the fiovs when it enlarges them */ 928 FUSE_DIMALLOC(&fdip->tick->tk_ms_fiov, fdip->finh, 929 fdip->indata, fdip->iosize); 930 931 fuse_setup_ihead(fdip->finh, fdip->tick, nid, op, fdip->iosize, pid, cred); 932 } 933 934 void 935 fdisp_make(struct fuse_dispatcher *fdip, enum fuse_opcode op, struct mount *mp, 936 uint64_t nid, struct thread *td, struct ucred *cred) 937 { 938 struct fuse_data *data = fuse_get_mpdata(mp); 939 RECTIFY_TDCR(td, cred); 940 941 return fdisp_make_pid(fdip, op, data, nid, td->td_proc->p_pid, cred); 942 } 943 944 void 945 fdisp_make_vp(struct fuse_dispatcher *fdip, enum fuse_opcode op, 946 struct vnode *vp, struct thread *td, struct ucred *cred) 947 { 948 struct mount *mp = vnode_mount(vp); 949 struct fuse_data *data = fuse_get_mpdata(mp); 950 951 RECTIFY_TDCR(td, cred); 952 return fdisp_make_pid(fdip, op, data, VTOI(vp), 953 td->td_proc->p_pid, cred); 954 } 955 956 /* Refresh a fuse_dispatcher so it can be reused, but don't zero its data */ 957 void 958 fdisp_refresh_vp(struct fuse_dispatcher *fdip, enum fuse_opcode op, 959 struct vnode *vp, struct thread *td, struct ucred *cred) 960 { 961 RECTIFY_TDCR(td, cred); 962 return fdisp_refresh_pid(fdip, op, vnode_mount(vp), VTOI(vp), 963 td->td_proc->p_pid, cred); 964 } 965 966 SDT_PROBE_DEFINE2(fusefs, , ipc, fdisp_wait_answ_error, "char*", "int"); 967 968 int 969 fdisp_wait_answ(struct fuse_dispatcher *fdip) 970 { 971 int err = 0; 972 973 fdip->answ_stat = 0; 974 fuse_insert_callback(fdip->tick, fuse_standard_handler); 975 fuse_insert_message(fdip->tick, false); 976 977 if ((err = fticket_wait_answer(fdip->tick))) { 978 fuse_lck_mtx_lock(fdip->tick->tk_aw_mtx); 979 980 if (fticket_answered(fdip->tick)) { 981 /* 982 * Just between noticing the interrupt and getting here, 983 * the standard handler has completed his job. 984 * So we drop the ticket and exit as usual. 985 */ 986 SDT_PROBE2(fusefs, , ipc, fdisp_wait_answ_error, 987 "IPC: interrupted, already answered", err); 988 fuse_lck_mtx_unlock(fdip->tick->tk_aw_mtx); 989 goto out; 990 } else { 991 /* 992 * So we were faster than the standard handler. 993 * Then by setting the answered flag we get *him* 994 * to drop the ticket. 995 */ 996 SDT_PROBE2(fusefs, , ipc, fdisp_wait_answ_error, 997 "IPC: interrupted, setting to answered", err); 998 fticket_set_answered(fdip->tick); 999 fuse_lck_mtx_unlock(fdip->tick->tk_aw_mtx); 1000 return err; 1001 } 1002 } 1003 1004 if (fdip->tick->tk_aw_errno == ENOTCONN) { 1005 /* The daemon died while we were waiting for a response */ 1006 err = ENOTCONN; 1007 goto out; 1008 } else if (fdip->tick->tk_aw_errno) { 1009 /* 1010 * There was some sort of communication error with the daemon 1011 * that the client wouldn't understand. 1012 */ 1013 SDT_PROBE2(fusefs, , ipc, fdisp_wait_answ_error, 1014 "IPC: explicit EIO-ing", fdip->tick->tk_aw_errno); 1015 err = EIO; 1016 goto out; 1017 } 1018 if ((err = fdip->tick->tk_aw_ohead.error)) { 1019 SDT_PROBE2(fusefs, , ipc, fdisp_wait_answ_error, 1020 "IPC: setting status", fdip->tick->tk_aw_ohead.error); 1021 /* 1022 * This means a "proper" fuse syscall error. 1023 * We record this value so the caller will 1024 * be able to know it's not a boring messaging 1025 * failure, if she wishes so (and if not, she can 1026 * just simply propagate the return value of this routine). 1027 * [XXX Maybe a bitflag would do the job too, 1028 * if other flags needed, this will be converted thusly.] 1029 */ 1030 fdip->answ_stat = err; 1031 goto out; 1032 } 1033 fdip->answ = fticket_resp(fdip->tick)->base; 1034 fdip->iosize = fticket_resp(fdip->tick)->len; 1035 1036 return 0; 1037 1038 out: 1039 return err; 1040 } 1041 1042 void 1043 fuse_ipc_init(void) 1044 { 1045 ticket_zone = uma_zcreate("fuse_ticket", sizeof(struct fuse_ticket), 1046 fticket_ctor, fticket_dtor, fticket_init, fticket_fini, 1047 UMA_ALIGN_PTR, 0); 1048 fuse_ticket_count = counter_u64_alloc(M_WAITOK); 1049 } 1050 1051 void 1052 fuse_ipc_destroy(void) 1053 { 1054 counter_u64_free(fuse_ticket_count); 1055 uma_zdestroy(ticket_zone); 1056 } 1057 1058 SDT_PROBE_DEFINE3(fusefs,, ipc, warn, "struct fuse_data*", "unsigned", "char*"); 1059 void 1060 fuse_warn(struct fuse_data *data, unsigned flag, const char *msg) 1061 { 1062 SDT_PROBE3(fusefs, , ipc, warn, data, flag, msg); 1063 if (!(data->dataflags & flag)) { 1064 printf("WARNING: FUSE protocol violation for server mounted at " 1065 "%s: %s " 1066 "This warning will not be repeated.\n", 1067 data->mp->mnt_stat.f_mntonname, msg); 1068 data->dataflags |= flag; 1069 } 1070 }
Cache object: a8383cdc802223dcd72533c48791192c
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