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 93SDT_PROVIDER_DECLARE(fusefs); 94/* 95 * Fuse trace probe: 96 * arg0: verbosity. Higher numbers give more verbose messages 97 * arg1: Textual message 98 */ 99SDT_PROBE_DEFINE2(fusefs, , ipc, trace, "int", "char*"); 100 101static 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); 103static void fuse_interrupt_send(struct fuse_ticket *otick, int err); 104static struct fuse_ticket *fticket_alloc(struct fuse_data *data); 105static void fticket_refresh(struct fuse_ticket *ftick); 106static void fticket_destroy(struct fuse_ticket *ftick); 107static int fticket_wait_answer(struct fuse_ticket *ftick); 108static inline int 109fticket_aw_pull_uio(struct fuse_ticket *ftick, 110 struct uio *uio); 111 112static int fuse_body_audit(struct fuse_ticket *ftick, size_t blen); 113 114static fuse_handler_t fuse_standard_handler; 115 116static counter_u64_t fuse_ticket_count; 117SYSCTL_COUNTER_U64(_vfs_fusefs_stats, OID_AUTO, ticket_count, CTLFLAG_RD, 118 &fuse_ticket_count, "Number of allocated tickets"); 119 120static long fuse_iov_permanent_bufsize = 1 << 19; 121 122SYSCTL_LONG(_vfs_fusefs, OID_AUTO, iov_permanent_bufsize, CTLFLAG_RW, 123 &fuse_iov_permanent_bufsize, 0, 124 "limit for permanently stored buffer size for fuse_iovs"); 125static int fuse_iov_credit = 16; 126 127SYSCTL_INT(_vfs_fusefs, OID_AUTO, iov_credit, CTLFLAG_RW, 128 &fuse_iov_credit, 0, 129 "how many times is an oversized fuse_iov tolerated"); 130 131MALLOC_DEFINE(M_FUSEMSG, "fuse_msgbuf", "fuse message buffer"); 132static uma_zone_t ticket_zone; 133 134/* 135 * TODO: figure out how to timeout INTERRUPT requests, because the daemon may 136 * leagally never respond 137 */ 138static int 139fuse_interrupt_callback(struct fuse_ticket *tick, struct uio *uio) 140{ 141 struct fuse_ticket *otick, *x_tick; 142 struct fuse_interrupt_in *fii; 143 struct fuse_data *data = tick->tk_data; 144 bool found = false; 145 146 fii = (struct fuse_interrupt_in*)((char*)tick->tk_ms_fiov.base + 147 sizeof(struct fuse_in_header)); 148 149 fuse_lck_mtx_lock(data->aw_mtx); 150 TAILQ_FOREACH_SAFE(otick, &data->aw_head, tk_aw_link, x_tick) { 151 if (otick->tk_unique == fii->unique) { 152 found = true; 153 break; 154 } 155 } 156 fuse_lck_mtx_unlock(data->aw_mtx); 157 158 if (!found) { 159 /* Original is already complete. Just return */ 160 return 0; 161 } 162 163 /* Clear the original ticket's interrupt association */ 164 otick->irq_unique = 0; 165 166 if (tick->tk_aw_ohead.error == ENOSYS) { 167 fsess_set_notimpl(data->mp, FUSE_INTERRUPT); 168 return 0; 169 } else if (tick->tk_aw_ohead.error == EAGAIN) { 170 /* 171 * There are two reasons we might get this: 172 * 1) the daemon received the INTERRUPT request before the 173 * original, or 174 * 2) the daemon received the INTERRUPT request after it 175 * completed the original request. 176 * In the first case we should re-send the INTERRUPT. In the 177 * second, we should ignore it. 178 */ 179 /* Resend */ 180 fuse_interrupt_send(otick, EINTR); 181 return 0; 182 } else { 183 /* Illegal FUSE_INTERRUPT response */ 184 return EINVAL; 185 } 186} 187 188/* Interrupt the operation otick. Return err as its error code */ 189void 190fuse_interrupt_send(struct fuse_ticket *otick, int err) 191{ 192 struct fuse_dispatcher fdi; 193 struct fuse_interrupt_in *fii; 194 struct fuse_in_header *ftick_hdr; 195 struct fuse_data *data = otick->tk_data; 196 struct fuse_ticket *tick, *xtick; 197 struct ucred reused_creds; 198 gid_t reused_groups[1]; 199 200 if (otick->irq_unique == 0) { 201 /* 202 * If the daemon hasn't yet received otick, then we can answer 203 * it ourselves and return. 204 */ 205 fuse_lck_mtx_lock(data->ms_mtx); 206 STAILQ_FOREACH_SAFE(tick, &otick->tk_data->ms_head, tk_ms_link, 207 xtick) { 208 if (tick == otick) { 209 STAILQ_REMOVE(&otick->tk_data->ms_head, tick, 210 fuse_ticket, tk_ms_link); 211 otick->tk_data->ms_count--; 212 otick->tk_ms_link.stqe_next = NULL; 213 fuse_lck_mtx_unlock(data->ms_mtx); 214 215 fuse_lck_mtx_lock(otick->tk_aw_mtx); 216 if (!fticket_answered(otick)) { 217 fticket_set_answered(otick); 218 otick->tk_aw_errno = err; 219 wakeup(otick); 220 } 221 fuse_lck_mtx_unlock(otick->tk_aw_mtx); 222 223 fuse_ticket_drop(tick); 224 return; 225 } 226 } 227 fuse_lck_mtx_unlock(data->ms_mtx); 228 229 /* 230 * If the fuse daemon doesn't support interrupts, then there's 231 * nothing more that we can do 232 */ 233 if (!fsess_isimpl(data->mp, FUSE_INTERRUPT)) 234 return; 235 236 /* 237 * If the fuse daemon has already received otick, then we must 238 * send FUSE_INTERRUPT. 239 */ 240 ftick_hdr = fticket_in_header(otick); 241 reused_creds.cr_uid = ftick_hdr->uid; 242 reused_groups[0] = ftick_hdr->gid; 243 reused_creds.cr_groups = reused_groups; 244 fdisp_init(&fdi, sizeof(*fii)); 245 fdisp_make_pid(&fdi, FUSE_INTERRUPT, data, ftick_hdr->nodeid, 246 ftick_hdr->pid, &reused_creds); 247 248 fii = fdi.indata; 249 fii->unique = otick->tk_unique; 250 fuse_insert_callback(fdi.tick, fuse_interrupt_callback); 251 252 otick->irq_unique = fdi.tick->tk_unique; 253 /* Interrupt ops should be delivered ASAP */ 254 fuse_insert_message(fdi.tick, true); 255 fdisp_destroy(&fdi); 256 } else { 257 /* This ticket has already been interrupted */ 258 } 259} 260 261void 262fiov_init(struct fuse_iov *fiov, size_t size) 263{ 264 uint32_t msize = FU_AT_LEAST(size); 265 266 fiov->len = 0; 267 268 fiov->base = malloc(msize, M_FUSEMSG, M_WAITOK | M_ZERO); 269 270 fiov->allocated_size = msize; 271 fiov->credit = fuse_iov_credit; 272} 273 274void 275fiov_teardown(struct fuse_iov *fiov) 276{ 277 MPASS(fiov->base != NULL); 278 free(fiov->base, M_FUSEMSG); 279} 280 281void 282fiov_adjust(struct fuse_iov *fiov, size_t size) 283{ 284 if (fiov->allocated_size < size || 285 (fuse_iov_permanent_bufsize >= 0 && 286 fiov->allocated_size - size > fuse_iov_permanent_bufsize && 287 --fiov->credit < 0)) { 288 289 fiov->base = realloc(fiov->base, FU_AT_LEAST(size), M_FUSEMSG, 290 M_WAITOK | M_ZERO); 291 if (!fiov->base) { 292 panic("FUSE: realloc failed"); 293 } 294 fiov->allocated_size = FU_AT_LEAST(size); 295 fiov->credit = fuse_iov_credit; 296 /* Clear data buffer after reallocation */ 297 bzero(fiov->base, size); 298 } else if (size > fiov->len) { 299 /* Clear newly extended portion of data buffer */ 300 bzero((char*)fiov->base + fiov->len, size - fiov->len); 301 } 302 fiov->len = size; 303} 304 305/* Resize the fiov if needed, and clear it's buffer */ 306void 307fiov_refresh(struct fuse_iov *fiov) 308{ 309 fiov_adjust(fiov, 0); 310} 311 312static int 313fticket_ctor(void *mem, int size, void *arg, int flags) 314{ 315 struct fuse_ticket *ftick = mem; 316 struct fuse_data *data = arg; 317 318 FUSE_ASSERT_MS_DONE(ftick); 319 FUSE_ASSERT_AW_DONE(ftick); 320 321 ftick->tk_data = data; 322 323 if (ftick->tk_unique != 0) 324 fticket_refresh(ftick); 325 326 /* May be truncated to 32 bits */ 327 ftick->tk_unique = atomic_fetchadd_long(&data->ticketer, 1); 328 if (ftick->tk_unique == 0) 329 ftick->tk_unique = atomic_fetchadd_long(&data->ticketer, 1); 330 331 ftick->irq_unique = 0; 332 333 refcount_init(&ftick->tk_refcount, 1); 334 counter_u64_add(fuse_ticket_count, 1); 335 336 return 0; 337} 338 339static void 340fticket_dtor(void *mem, int size, void *arg) 341{ 342#ifdef INVARIANTS 343 struct fuse_ticket *ftick = mem; 344#endif 345 346 FUSE_ASSERT_MS_DONE(ftick); 347 FUSE_ASSERT_AW_DONE(ftick); 348 349 counter_u64_add(fuse_ticket_count, -1); 350} 351 352static int 353fticket_init(void *mem, int size, int flags) 354{ 355 struct fuse_ticket *ftick = mem; 356 357 bzero(ftick, sizeof(struct fuse_ticket)); 358 359 fiov_init(&ftick->tk_ms_fiov, sizeof(struct fuse_in_header)); 360 ftick->tk_ms_type = FT_M_FIOV; 361 362 mtx_init(&ftick->tk_aw_mtx, "fuse answer delivery mutex", NULL, MTX_DEF); 363 fiov_init(&ftick->tk_aw_fiov, 0); 364 ftick->tk_aw_type = FT_A_FIOV; 365 366 return 0; 367} 368 369static void 370fticket_fini(void *mem, int size) 371{ 372 struct fuse_ticket *ftick = mem; 373 374 fiov_teardown(&ftick->tk_ms_fiov); 375 fiov_teardown(&ftick->tk_aw_fiov); 376 mtx_destroy(&ftick->tk_aw_mtx); 377} 378 379static inline struct fuse_ticket * 380fticket_alloc(struct fuse_data *data) 381{ 382 return uma_zalloc_arg(ticket_zone, data, M_WAITOK); 383} 384 385static inline void 386fticket_destroy(struct fuse_ticket *ftick) 387{ 388 return uma_zfree(ticket_zone, ftick); 389} 390 391static inline 392void 393fticket_refresh(struct fuse_ticket *ftick) 394{ 395 FUSE_ASSERT_MS_DONE(ftick); 396 FUSE_ASSERT_AW_DONE(ftick); 397 398 fiov_refresh(&ftick->tk_ms_fiov); 399 ftick->tk_ms_bufdata = NULL; 400 ftick->tk_ms_bufsize = 0; 401 ftick->tk_ms_type = FT_M_FIOV; 402 403 bzero(&ftick->tk_aw_ohead, sizeof(struct fuse_out_header)); 404 405 fiov_refresh(&ftick->tk_aw_fiov); 406 ftick->tk_aw_errno = 0; 407 ftick->tk_aw_bufdata = NULL; 408 ftick->tk_aw_bufsize = 0; 409 ftick->tk_aw_type = FT_A_FIOV; 410 411 ftick->tk_flag = 0; 412} 413 414/* Prepar the ticket to be reused, but don't clear its data buffers */ 415static inline void 416fticket_reset(struct fuse_ticket *ftick) 417{ 418 FUSE_ASSERT_MS_DONE(ftick); 419 FUSE_ASSERT_AW_DONE(ftick); 420 421 ftick->tk_ms_bufdata = NULL; 422 ftick->tk_ms_bufsize = 0; 423 ftick->tk_ms_type = FT_M_FIOV; 424 425 bzero(&ftick->tk_aw_ohead, sizeof(struct fuse_out_header)); 426 427 ftick->tk_aw_errno = 0; 428 ftick->tk_aw_bufdata = NULL; 429 ftick->tk_aw_bufsize = 0; 430 ftick->tk_aw_type = FT_A_FIOV; 431 432 ftick->tk_flag = 0; 433} 434 435static int 436fticket_wait_answer(struct fuse_ticket *ftick) 437{ 438 struct thread *td = curthread; 439 sigset_t blockedset, oldset; 440 int err = 0, stops_deferred; 441 struct fuse_data *data = ftick->tk_data; 442 bool interrupted = false; 443 444 if (fsess_isimpl(ftick->tk_data->mp, FUSE_INTERRUPT) && 445 data->dataflags & FSESS_INTR) { 446 SIGEMPTYSET(blockedset); 447 } else { 448 /* Block all signals except (implicitly) SIGKILL */ 449 SIGFILLSET(blockedset); 450 } 451 stops_deferred = sigdeferstop(SIGDEFERSTOP_SILENT); 452 kern_sigprocmask(td, SIG_BLOCK, NULL, &oldset, 0); 453 454 fuse_lck_mtx_lock(ftick->tk_aw_mtx); 455 456retry: 457 if (fticket_answered(ftick)) { 458 goto out; 459 } 460 461 if (fdata_get_dead(data)) { 462 err = ENOTCONN; 463 fticket_set_answered(ftick); 464 goto out; 465 } 466 kern_sigprocmask(td, SIG_BLOCK, &blockedset, NULL, 0); 467 err = msleep(ftick, &ftick->tk_aw_mtx, PCATCH, "fu_ans", 468 data->daemon_timeout * hz); 469 kern_sigprocmask(td, SIG_SETMASK, &oldset, NULL, 0); 470 if (err == EWOULDBLOCK) { 471 SDT_PROBE2(fusefs, , ipc, trace, 3, 472 "fticket_wait_answer: EWOULDBLOCK"); 473#ifdef XXXIP /* die conditionally */ 474 if (!fdata_get_dead(data)) { 475 fdata_set_dead(data); 476 } 477#endif 478 err = ETIMEDOUT; 479 fticket_set_answered(ftick); 480 } else if ((err == EINTR || err == ERESTART)) { 481 /* 482 * Whether we get EINTR or ERESTART depends on whether 483 * SA_RESTART was set by sigaction(2). 484 * 485 * Try to interrupt the operation and wait for an EINTR response 486 * to the original operation. If the file system does not 487 * support FUSE_INTERRUPT, then we'll just wait for it to 488 * complete like normal. If it does support FUSE_INTERRUPT, 489 * then it will either respond EINTR to the original operation, 490 * or EAGAIN to the interrupt. 491 */ 492 sigset_t tmpset; 493 494 SDT_PROBE2(fusefs, , ipc, trace, 4, 495 "fticket_wait_answer: interrupt"); 496 fuse_lck_mtx_unlock(ftick->tk_aw_mtx); 497 fuse_interrupt_send(ftick, err); 498 499 PROC_LOCK(td->td_proc); 500 mtx_lock(&td->td_proc->p_sigacts->ps_mtx); 501 tmpset = td->td_proc->p_siglist; 502 SIGSETOR(tmpset, td->td_siglist); 503 mtx_unlock(&td->td_proc->p_sigacts->ps_mtx); 504 PROC_UNLOCK(td->td_proc); 505 506 fuse_lck_mtx_lock(ftick->tk_aw_mtx); 507 if (!interrupted && !SIGISMEMBER(tmpset, SIGKILL)) { 508 /* 509 * Block all signals while we wait for an interrupt 510 * response. The protocol doesn't discriminate between 511 * different signals. 512 */ 513 SIGFILLSET(blockedset); 514 interrupted = true; 515 goto retry; 516 } else { 517 /* 518 * Return immediately for fatal signals, or if this is 519 * the second interruption. We should only be 520 * interrupted twice if the thread is stopped, for 521 * example during sigexit. 522 */ 523 } 524 } else if (err) { 525 SDT_PROBE2(fusefs, , ipc, trace, 6, 526 "fticket_wait_answer: other error"); 527 } else { 528 SDT_PROBE2(fusefs, , ipc, trace, 7, "fticket_wait_answer: OK"); 529 } 530out: 531 if (!(err || fticket_answered(ftick))) { 532 SDT_PROBE2(fusefs, , ipc, trace, 1, 533 "FUSE: requester was woken up but still no answer"); 534 err = ENXIO; 535 } 536 fuse_lck_mtx_unlock(ftick->tk_aw_mtx); 537 sigallowstop(stops_deferred); 538 539 return err; 540} 541 542static inline 543int 544fticket_aw_pull_uio(struct fuse_ticket *ftick, struct uio *uio) 545{ 546 int err = 0; 547 size_t len = uio_resid(uio); 548 549 if (len) { 550 switch (ftick->tk_aw_type) { 551 case FT_A_FIOV: 552 fiov_adjust(fticket_resp(ftick), len); 553 err = uiomove(fticket_resp(ftick)->base, len, uio); 554 break; 555 556 case FT_A_BUF: 557 ftick->tk_aw_bufsize = len; 558 err = uiomove(ftick->tk_aw_bufdata, len, uio); 559 break; 560 561 default: 562 panic("FUSE: unknown answer type for ticket %p", ftick); 563 } 564 } 565 return err; 566} 567 568int 569fticket_pull(struct fuse_ticket *ftick, struct uio *uio) 570{ 571 int err = 0; 572 573 if (ftick->tk_aw_ohead.error) { 574 return 0; 575 } 576 err = fuse_body_audit(ftick, uio_resid(uio)); 577 if (!err) { 578 err = fticket_aw_pull_uio(ftick, uio); 579 } 580 return err; 581} 582 583struct fuse_data * 584fdata_alloc(struct cdev *fdev, struct ucred *cred) 585{ 586 struct fuse_data *data; 587 588 data = malloc(sizeof(struct fuse_data), M_FUSEMSG, M_WAITOK | M_ZERO); 589 590 data->fdev = fdev; 591 mtx_init(&data->ms_mtx, "fuse message list mutex", NULL, MTX_DEF); 592 STAILQ_INIT(&data->ms_head); 593 data->ms_count = 0; 594 knlist_init_mtx(&data->ks_rsel.si_note, &data->ms_mtx); 595 mtx_init(&data->aw_mtx, "fuse answer list mutex", NULL, MTX_DEF); 596 TAILQ_INIT(&data->aw_head); 597 data->daemoncred = crhold(cred); 598 data->daemon_timeout = FUSE_DEFAULT_DAEMON_TIMEOUT; 599 sx_init(&data->rename_lock, "fuse rename lock"); 600 data->ref = 1; 601 602 return data; 603} 604 605void 606fdata_trydestroy(struct fuse_data *data) 607{ 608 data->ref--; 609 MPASS(data->ref >= 0); 610 if (data->ref != 0) 611 return; 612 613 /* Driving off stage all that stuff thrown at device... */ 614 sx_destroy(&data->rename_lock); 615 crfree(data->daemoncred); 616 mtx_destroy(&data->aw_mtx); 617 knlist_delete(&data->ks_rsel.si_note, curthread, 0); 618 knlist_destroy(&data->ks_rsel.si_note); 619 mtx_destroy(&data->ms_mtx); 620 621 free(data, M_FUSEMSG); 622} 623 624void 625fdata_set_dead(struct fuse_data *data) 626{ 627 FUSE_LOCK(); 628 if (fdata_get_dead(data)) { 629 FUSE_UNLOCK(); 630 return; 631 } 632 fuse_lck_mtx_lock(data->ms_mtx); 633 data->dataflags |= FSESS_DEAD; 634 wakeup_one(data); 635 selwakeuppri(&data->ks_rsel, PZERO + 1); 636 wakeup(&data->ticketer); 637 fuse_lck_mtx_unlock(data->ms_mtx); 638 FUSE_UNLOCK(); 639} 640 641struct fuse_ticket * 642fuse_ticket_fetch(struct fuse_data *data) 643{ 644 int err = 0; 645 struct fuse_ticket *ftick; 646 647 ftick = fticket_alloc(data); 648 649 if (!(data->dataflags & FSESS_INITED)) { 650 /* Sleep until get answer for INIT messsage */ 651 FUSE_LOCK(); 652 if (!(data->dataflags & FSESS_INITED) && data->ticketer > 2) { 653 err = msleep(&data->ticketer, &fuse_mtx, PCATCH | PDROP, 654 "fu_ini", 0); 655 if (err) 656 fdata_set_dead(data); 657 } else 658 FUSE_UNLOCK(); 659 } 660 return ftick; 661} 662 663int 664fuse_ticket_drop(struct fuse_ticket *ftick) 665{ 666 int die; 667 668 die = refcount_release(&ftick->tk_refcount); 669 if (die) 670 fticket_destroy(ftick); 671 672 return die; 673} 674 675void 676fuse_insert_callback(struct fuse_ticket *ftick, fuse_handler_t * handler) 677{ 678 if (fdata_get_dead(ftick->tk_data)) { 679 return; 680 } 681 ftick->tk_aw_handler = handler; 682 683 fuse_lck_mtx_lock(ftick->tk_data->aw_mtx); 684 fuse_aw_push(ftick); 685 fuse_lck_mtx_unlock(ftick->tk_data->aw_mtx); 686} 687 688/* 689 * Insert a new upgoing ticket into the message queue 690 * 691 * If urgent is true, insert at the front of the queue. Otherwise, insert in 692 * FIFO order. 693 */ 694void 695fuse_insert_message(struct fuse_ticket *ftick, bool urgent) 696{ 697 if (ftick->tk_flag & FT_DIRTY) { 698 panic("FUSE: ticket reused without being refreshed"); 699 } 700 ftick->tk_flag |= FT_DIRTY; 701 702 if (fdata_get_dead(ftick->tk_data)) { 703 return; 704 } 705 fuse_lck_mtx_lock(ftick->tk_data->ms_mtx); 706 if (urgent) 707 fuse_ms_push_head(ftick); 708 else 709 fuse_ms_push(ftick); 710 wakeup_one(ftick->tk_data); 711 selwakeuppri(&ftick->tk_data->ks_rsel, PZERO + 1); 712 KNOTE_LOCKED(&ftick->tk_data->ks_rsel.si_note, 0); 713 fuse_lck_mtx_unlock(ftick->tk_data->ms_mtx); 714} 715 716static int 717fuse_body_audit(struct fuse_ticket *ftick, size_t blen) 718{ 719 int err = 0; 720 enum fuse_opcode opcode; 721 722 opcode = fticket_opcode(ftick); 723 724 switch (opcode) { 725 case FUSE_BMAP: 726 err = (blen == sizeof(struct fuse_bmap_out)) ? 0 : EINVAL; 727 break; 728 729 case FUSE_LINK: 730 case FUSE_LOOKUP: 731 case FUSE_MKDIR: 732 case FUSE_MKNOD: 733 case FUSE_SYMLINK: 734 if (fuse_libabi_geq(ftick->tk_data, 7, 9)) { 735 err = (blen == sizeof(struct fuse_entry_out)) ? 736 0 : EINVAL; 737 } else { 738 err = (blen == FUSE_COMPAT_ENTRY_OUT_SIZE) ? 0 : EINVAL; 739 } 740 break; 741 742 case FUSE_FORGET: 743 panic("FUSE: a handler has been intalled for FUSE_FORGET"); 744 break; 745 746 case FUSE_GETATTR: 747 case FUSE_SETATTR: 748 if (fuse_libabi_geq(ftick->tk_data, 7, 9)) { 749 err = (blen == sizeof(struct fuse_attr_out)) ? 750 0 : EINVAL; 751 } else { 752 err = (blen == FUSE_COMPAT_ATTR_OUT_SIZE) ? 0 : EINVAL; 753 } 754 break; 755 756 case FUSE_READLINK: 757 err = (PAGE_SIZE >= blen) ? 0 : EINVAL; 758 break; 759 760 case FUSE_UNLINK: 761 err = (blen == 0) ? 0 : EINVAL; 762 break; 763 764 case FUSE_RMDIR: 765 err = (blen == 0) ? 0 : EINVAL; 766 break; 767 768 case FUSE_RENAME: 769 err = (blen == 0) ? 0 : EINVAL; 770 break; 771 772 case FUSE_OPEN: 773 err = (blen == sizeof(struct fuse_open_out)) ? 0 : EINVAL; 774 break; 775 776 case FUSE_READ: 777 err = (((struct fuse_read_in *)( 778 (char *)ftick->tk_ms_fiov.base + 779 sizeof(struct fuse_in_header) 780 ))->size >= blen) ? 0 : EINVAL; 781 break; 782 783 case FUSE_WRITE: 784 err = (blen == sizeof(struct fuse_write_out)) ? 0 : EINVAL; 785 break; 786 787 case FUSE_STATFS: 788 if (fuse_libabi_geq(ftick->tk_data, 7, 4)) { 789 err = (blen == sizeof(struct fuse_statfs_out)) ? 790 0 : EINVAL; 791 } else { 792 err = (blen == FUSE_COMPAT_STATFS_SIZE) ? 0 : EINVAL; 793 } 794 break; 795 796 case FUSE_RELEASE: 797 err = (blen == 0) ? 0 : EINVAL; 798 break; 799 800 case FUSE_FSYNC: 801 err = (blen == 0) ? 0 : EINVAL; 802 break; 803 804 case FUSE_SETXATTR: 805 err = (blen == 0) ? 0 : EINVAL; 806 break; 807 808 case FUSE_GETXATTR: 809 case FUSE_LISTXATTR: 810 /* 811 * These can have varying response lengths, and 0 length 812 * isn't necessarily invalid. 813 */ 814 err = 0; 815 break; 816 817 case FUSE_REMOVEXATTR: 818 err = (blen == 0) ? 0 : EINVAL; 819 break; 820 821 case FUSE_FLUSH: 822 err = (blen == 0) ? 0 : EINVAL; 823 break; 824 825 case FUSE_INIT: 826 if (blen == sizeof(struct fuse_init_out) || 827 blen == FUSE_COMPAT_INIT_OUT_SIZE || 828 blen == FUSE_COMPAT_22_INIT_OUT_SIZE) { 829 err = 0; 830 } else { 831 err = EINVAL; 832 } 833 break; 834 835 case FUSE_OPENDIR: 836 err = (blen == sizeof(struct fuse_open_out)) ? 0 : EINVAL; 837 break; 838 839 case FUSE_READDIR: 840 err = (((struct fuse_read_in *)( 841 (char *)ftick->tk_ms_fiov.base + 842 sizeof(struct fuse_in_header) 843 ))->size >= blen) ? 0 : EINVAL; 844 break; 845 846 case FUSE_RELEASEDIR: 847 err = (blen == 0) ? 0 : EINVAL; 848 break; 849 850 case FUSE_FSYNCDIR: 851 err = (blen == 0) ? 0 : EINVAL; 852 break; 853 854 case FUSE_GETLK: 855 err = (blen == sizeof(struct fuse_lk_out)) ? 0 : EINVAL; 856 break; 857 858 case FUSE_SETLK: 859 err = (blen == 0) ? 0 : EINVAL; 860 break; 861 862 case FUSE_SETLKW: 863 err = (blen == 0) ? 0 : EINVAL; 864 break; 865 866 case FUSE_ACCESS: 867 err = (blen == 0) ? 0 : EINVAL; 868 break; 869 870 case FUSE_CREATE: 871 if (fuse_libabi_geq(ftick->tk_data, 7, 9)) { 872 err = (blen == sizeof(struct fuse_entry_out) + 873 sizeof(struct fuse_open_out)) ? 0 : EINVAL; 874 } else { 875 err = (blen == FUSE_COMPAT_ENTRY_OUT_SIZE + 876 sizeof(struct fuse_open_out)) ? 0 : EINVAL; 877 } 878 break; 879 880 case FUSE_DESTROY: 881 err = (blen == 0) ? 0 : EINVAL; 882 break; 883 884 default: 885 panic("FUSE: opcodes out of sync (%d)\n", opcode); 886 } 887 888 return err; 889} 890 891static inline void 892fuse_setup_ihead(struct fuse_in_header *ihead, struct fuse_ticket *ftick, 893 uint64_t nid, enum fuse_opcode op, size_t blen, pid_t pid, 894 struct ucred *cred) 895{ 896 ihead->len = sizeof(*ihead) + blen; 897 ihead->unique = ftick->tk_unique; 898 ihead->nodeid = nid; 899 ihead->opcode = op; 900 901 ihead->pid = pid; 902 ihead->uid = cred->cr_uid; 903 ihead->gid = cred->cr_groups[0]; 904} 905 906/* 907 * fuse_standard_handler just pulls indata and wakes up pretender. 908 * Doesn't try to interpret data, that's left for the pretender. 909 * Though might do a basic size verification before the pull-in takes place 910 */ 911 912static int 913fuse_standard_handler(struct fuse_ticket *ftick, struct uio *uio) 914{ 915 int err = 0; 916 917 err = fticket_pull(ftick, uio); 918 919 fuse_lck_mtx_lock(ftick->tk_aw_mtx); 920 921 if (!fticket_answered(ftick)) { 922 fticket_set_answered(ftick); 923 ftick->tk_aw_errno = err; 924 wakeup(ftick); 925 } 926 fuse_lck_mtx_unlock(ftick->tk_aw_mtx); 927 928 return err; 929} 930 931/* 932 * Reinitialize a dispatcher from a pid and node id, without resizing or 933 * clearing its data buffers 934 */ 935static void 936fdisp_refresh_pid(struct fuse_dispatcher *fdip, enum fuse_opcode op, 937 struct mount *mp, uint64_t nid, pid_t pid, struct ucred *cred) 938{ 939 MPASS(fdip->tick); 940 MPASS2(sizeof(fdip->finh) + fdip->iosize <= fdip->tick->tk_ms_fiov.len, 941 "Must use fdisp_make_pid to increase the size of the fiov"); 942 fticket_reset(fdip->tick); 943 944 FUSE_DIMALLOC(&fdip->tick->tk_ms_fiov, fdip->finh, 945 fdip->indata, fdip->iosize); 946 947 fuse_setup_ihead(fdip->finh, fdip->tick, nid, op, fdip->iosize, pid, 948 cred); 949} 950 951/* Initialize a dispatcher from a pid and node id */ 952static void 953fdisp_make_pid(struct fuse_dispatcher *fdip, enum fuse_opcode op, 954 struct fuse_data *data, uint64_t nid, pid_t pid, struct ucred *cred) 955{ 956 if (fdip->tick) { 957 fticket_refresh(fdip->tick); 958 } else { 959 fdip->tick = fuse_ticket_fetch(data); 960 } 961 962 /* FUSE_DIMALLOC will bzero the fiovs when it enlarges them */ 963 FUSE_DIMALLOC(&fdip->tick->tk_ms_fiov, fdip->finh, 964 fdip->indata, fdip->iosize); 965 966 fuse_setup_ihead(fdip->finh, fdip->tick, nid, op, fdip->iosize, pid, cred); 967} 968 969void 970fdisp_make(struct fuse_dispatcher *fdip, enum fuse_opcode op, struct mount *mp, 971 uint64_t nid, struct thread *td, struct ucred *cred) 972{ 973 struct fuse_data *data = fuse_get_mpdata(mp); 974 RECTIFY_TDCR(td, cred); 975 976 return fdisp_make_pid(fdip, op, data, nid, td->td_proc->p_pid, cred); 977} 978 979void 980fdisp_make_vp(struct fuse_dispatcher *fdip, enum fuse_opcode op, 981 struct vnode *vp, struct thread *td, struct ucred *cred) 982{ 983 struct mount *mp = vnode_mount(vp); 984 struct fuse_data *data = fuse_get_mpdata(mp); 985 986 RECTIFY_TDCR(td, cred); 987 return fdisp_make_pid(fdip, op, data, VTOI(vp), 988 td->td_proc->p_pid, cred); 989} 990 991/* Refresh a fuse_dispatcher so it can be reused, but don't zero its data */ 992void 993fdisp_refresh_vp(struct fuse_dispatcher *fdip, enum fuse_opcode op, 994 struct vnode *vp, struct thread *td, struct ucred *cred) 995{ 996 RECTIFY_TDCR(td, cred); 997 return fdisp_refresh_pid(fdip, op, vnode_mount(vp), VTOI(vp), 998 td->td_proc->p_pid, cred); 999} 1000 1001void 1002fdisp_refresh(struct fuse_dispatcher *fdip) 1003{ 1004 fticket_refresh(fdip->tick); 1005} 1006 1007SDT_PROBE_DEFINE2(fusefs, , ipc, fdisp_wait_answ_error, "char*", "int"); 1008 1009int 1010fdisp_wait_answ(struct fuse_dispatcher *fdip) 1011{ 1012 int err = 0; 1013 1014 fdip->answ_stat = 0; 1015 fuse_insert_callback(fdip->tick, fuse_standard_handler); 1016 fuse_insert_message(fdip->tick, false); 1017 1018 if ((err = fticket_wait_answer(fdip->tick))) { 1019 fuse_lck_mtx_lock(fdip->tick->tk_aw_mtx); 1020 1021 if (fticket_answered(fdip->tick)) { 1022 /* 1023 * Just between noticing the interrupt and getting here, 1024 * the standard handler has completed his job. 1025 * So we drop the ticket and exit as usual. 1026 */ 1027 SDT_PROBE2(fusefs, , ipc, fdisp_wait_answ_error, 1028 "IPC: interrupted, already answered", err); 1029 fuse_lck_mtx_unlock(fdip->tick->tk_aw_mtx); 1030 goto out; 1031 } else { 1032 /* 1033 * So we were faster than the standard handler. 1034 * Then by setting the answered flag we get *him* 1035 * to drop the ticket. 1036 */ 1037 SDT_PROBE2(fusefs, , ipc, fdisp_wait_answ_error, 1038 "IPC: interrupted, setting to answered", err); 1039 fticket_set_answered(fdip->tick); 1040 fuse_lck_mtx_unlock(fdip->tick->tk_aw_mtx); 1041 return err; 1042 } 1043 } 1044 1045 if (fdip->tick->tk_aw_errno == ENOTCONN) { 1046 /* The daemon died while we were waiting for a response */ 1047 err = ENOTCONN; 1048 goto out; 1049 } else if (fdip->tick->tk_aw_errno) { 1050 /* 1051 * There was some sort of communication error with the daemon 1052 * that the client wouldn't understand. 1053 */ 1054 SDT_PROBE2(fusefs, , ipc, fdisp_wait_answ_error, 1055 "IPC: explicit EIO-ing", fdip->tick->tk_aw_errno); 1056 err = EIO; 1057 goto out; 1058 } 1059 if ((err = fdip->tick->tk_aw_ohead.error)) { 1060 SDT_PROBE2(fusefs, , ipc, fdisp_wait_answ_error, 1061 "IPC: setting status", fdip->tick->tk_aw_ohead.error); 1062 /* 1063 * This means a "proper" fuse syscall error. 1064 * We record this value so the caller will 1065 * be able to know it's not a boring messaging 1066 * failure, if she wishes so (and if not, she can 1067 * just simply propagate the return value of this routine). 1068 * [XXX Maybe a bitflag would do the job too, 1069 * if other flags needed, this will be converted thusly.] 1070 */ 1071 fdip->answ_stat = err; 1072 goto out; 1073 } 1074 fdip->answ = fticket_resp(fdip->tick)->base; 1075 fdip->iosize = fticket_resp(fdip->tick)->len; 1076 1077 return 0; 1078 1079out: 1080 return err; 1081} 1082 1083void 1084fuse_ipc_init(void) 1085{ 1086 ticket_zone = uma_zcreate("fuse_ticket", sizeof(struct fuse_ticket), 1087 fticket_ctor, fticket_dtor, fticket_init, fticket_fini, 1088 UMA_ALIGN_PTR, 0); 1089 fuse_ticket_count = counter_u64_alloc(M_WAITOK); 1090} 1091 1092void 1093fuse_ipc_destroy(void) 1094{ 1095 counter_u64_free(fuse_ticket_count); 1096 uma_zdestroy(ticket_zone); 1097} 1098