1 /*- 2 * Copyright (c) 1999-2004 Poul-Henning Kamp 3 * Copyright (c) 1999 Michael Smith 4 * Copyright (c) 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * (c) UNIX System Laboratories, Inc. 7 * All or some portions of this file are derived from material licensed 8 * to the University of California by American Telephone and Telegraph 9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 10 * the permission of UNIX System Laboratories, Inc. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37 #include <sys/cdefs.h> 38 __FBSDID("$FreeBSD$"); 39 40 #include <sys/param.h> 41 #include <sys/conf.h> 42 #include <sys/fcntl.h> 43 #include <sys/jail.h> 44 #include <sys/kernel.h> 45 #include <sys/libkern.h> 46 #include <sys/malloc.h> 47 #include <sys/mount.h> 48 #include <sys/mutex.h> 49 #include <sys/namei.h> 50 #include <sys/priv.h> 51 #include <sys/proc.h> 52 #include <sys/filedesc.h> 53 #include <sys/reboot.h> 54 #include <sys/sbuf.h> 55 #include <sys/syscallsubr.h> 56 #include <sys/sysproto.h> 57 #include <sys/sx.h> 58 #include <sys/sysctl.h> 59 #include <sys/sysent.h> 60 #include <sys/systm.h> 61 #include <sys/vnode.h> 62 #include <vm/uma.h> 63 64 #include <geom/geom.h> 65 66 #include <machine/stdarg.h> 67 68 #include <security/audit/audit.h> 69 #include <security/mac/mac_framework.h> 70 71 #define VFS_MOUNTARG_SIZE_MAX (1024 * 64) 72 73 static int vfs_domount(struct thread *td, const char *fstype, char *fspath, 74 uint64_t fsflags, struct vfsoptlist **optlist); 75 static void free_mntarg(struct mntarg *ma); 76 77 static int usermount = 0; 78 SYSCTL_INT(_vfs, OID_AUTO, usermount, CTLFLAG_RW, &usermount, 0, 79 "Unprivileged users may mount and unmount file systems"); 80 81 MALLOC_DEFINE(M_MOUNT, "mount", "vfs mount structure"); 82 static uma_zone_t mount_zone; 83 84 /* List of mounted filesystems. */ 85 struct mntlist mountlist = TAILQ_HEAD_INITIALIZER(mountlist); 86 87 /* For any iteration/modification of mountlist */ 88 struct mtx mountlist_mtx; 89 MTX_SYSINIT(mountlist, &mountlist_mtx, "mountlist", MTX_DEF); 90 91 /* 92 * Global opts, taken by all filesystems 93 */ 94 static const char *global_opts[] = { 95 "errmsg", 96 "fstype", 97 "fspath", 98 "ro", 99 "rw", 100 "nosuid", 101 "noexec", 102 NULL 103 }; 104 105 static int 106 mount_init(void *mem, int size, int flags) 107 { 108 struct mount *mp; 109 110 mp = (struct mount *)mem; 111 mtx_init(&mp->mnt_mtx, "struct mount mtx", NULL, MTX_DEF); 112 lockinit(&mp->mnt_explock, PVFS, "explock", 0, 0); 113 return (0); 114 } 115 116 static void 117 mount_fini(void *mem, int size) 118 { 119 struct mount *mp; 120 121 mp = (struct mount *)mem; 122 lockdestroy(&mp->mnt_explock); 123 mtx_destroy(&mp->mnt_mtx); 124 } 125 126 static void 127 vfs_mount_init(void *dummy __unused) 128 { 129 130 mount_zone = uma_zcreate("Mountpoints", sizeof(struct mount), NULL, 131 NULL, mount_init, mount_fini, UMA_ALIGN_PTR, UMA_ZONE_NOFREE); 132 } 133 SYSINIT(vfs_mount, SI_SUB_VFS, SI_ORDER_ANY, vfs_mount_init, NULL); 134 135 /* 136 * --------------------------------------------------------------------- 137 * Functions for building and sanitizing the mount options 138 */ 139 140 /* Remove one mount option. */ 141 static void 142 vfs_freeopt(struct vfsoptlist *opts, struct vfsopt *opt) 143 { 144 145 TAILQ_REMOVE(opts, opt, link); 146 free(opt->name, M_MOUNT); 147 if (opt->value != NULL) 148 free(opt->value, M_MOUNT); 149 free(opt, M_MOUNT); 150 } 151 152 /* Release all resources related to the mount options. */ 153 void 154 vfs_freeopts(struct vfsoptlist *opts) 155 { 156 struct vfsopt *opt; 157 158 while (!TAILQ_EMPTY(opts)) { 159 opt = TAILQ_FIRST(opts); 160 vfs_freeopt(opts, opt); 161 } 162 free(opts, M_MOUNT); 163 } 164 165 void 166 vfs_deleteopt(struct vfsoptlist *opts, const char *name) 167 { 168 struct vfsopt *opt, *temp; 169 170 if (opts == NULL) 171 return; 172 TAILQ_FOREACH_SAFE(opt, opts, link, temp) { 173 if (strcmp(opt->name, name) == 0) 174 vfs_freeopt(opts, opt); 175 } 176 } 177 178 static int 179 vfs_isopt_ro(const char *opt) 180 { 181 182 if (strcmp(opt, "ro") == 0 || strcmp(opt, "rdonly") == 0 || 183 strcmp(opt, "norw") == 0) 184 return (1); 185 return (0); 186 } 187 188 static int 189 vfs_isopt_rw(const char *opt) 190 { 191 192 if (strcmp(opt, "rw") == 0 || strcmp(opt, "noro") == 0) 193 return (1); 194 return (0); 195 } 196 197 /* 198 * Check if options are equal (with or without the "no" prefix). 199 */ 200 static int 201 vfs_equalopts(const char *opt1, const char *opt2) 202 { 203 char *p; 204 205 /* "opt" vs. "opt" or "noopt" vs. "noopt" */ 206 if (strcmp(opt1, opt2) == 0) 207 return (1); 208 /* "noopt" vs. "opt" */ 209 if (strncmp(opt1, "no", 2) == 0 && strcmp(opt1 + 2, opt2) == 0) 210 return (1); 211 /* "opt" vs. "noopt" */ 212 if (strncmp(opt2, "no", 2) == 0 && strcmp(opt1, opt2 + 2) == 0) 213 return (1); 214 while ((p = strchr(opt1, '.')) != NULL && 215 !strncmp(opt1, opt2, ++p - opt1)) { 216 opt2 += p - opt1; 217 opt1 = p; 218 /* "foo.noopt" vs. "foo.opt" */ 219 if (strncmp(opt1, "no", 2) == 0 && strcmp(opt1 + 2, opt2) == 0) 220 return (1); 221 /* "foo.opt" vs. "foo.noopt" */ 222 if (strncmp(opt2, "no", 2) == 0 && strcmp(opt1, opt2 + 2) == 0) 223 return (1); 224 } 225 /* "ro" / "rdonly" / "norw" / "rw" / "noro" */ 226 if ((vfs_isopt_ro(opt1) || vfs_isopt_rw(opt1)) && 227 (vfs_isopt_ro(opt2) || vfs_isopt_rw(opt2))) 228 return (1); 229 return (0); 230 } 231 232 /* 233 * If a mount option is specified several times, 234 * (with or without the "no" prefix) only keep 235 * the last occurrence of it. 236 */ 237 static void 238 vfs_sanitizeopts(struct vfsoptlist *opts) 239 { 240 struct vfsopt *opt, *opt2, *tmp; 241 242 TAILQ_FOREACH_REVERSE(opt, opts, vfsoptlist, link) { 243 opt2 = TAILQ_PREV(opt, vfsoptlist, link); 244 while (opt2 != NULL) { 245 if (vfs_equalopts(opt->name, opt2->name)) { 246 tmp = TAILQ_PREV(opt2, vfsoptlist, link); 247 vfs_freeopt(opts, opt2); 248 opt2 = tmp; 249 } else { 250 opt2 = TAILQ_PREV(opt2, vfsoptlist, link); 251 } 252 } 253 } 254 } 255 256 /* 257 * Build a linked list of mount options from a struct uio. 258 */ 259 int 260 vfs_buildopts(struct uio *auio, struct vfsoptlist **options) 261 { 262 struct vfsoptlist *opts; 263 struct vfsopt *opt; 264 size_t memused, namelen, optlen; 265 unsigned int i, iovcnt; 266 int error; 267 268 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 269 TAILQ_INIT(opts); 270 memused = 0; 271 iovcnt = auio->uio_iovcnt; 272 for (i = 0; i < iovcnt; i += 2) { 273 namelen = auio->uio_iov[i].iov_len; 274 optlen = auio->uio_iov[i + 1].iov_len; 275 memused += sizeof(struct vfsopt) + optlen + namelen; 276 /* 277 * Avoid consuming too much memory, and attempts to overflow 278 * memused. 279 */ 280 if (memused > VFS_MOUNTARG_SIZE_MAX || 281 optlen > VFS_MOUNTARG_SIZE_MAX || 282 namelen > VFS_MOUNTARG_SIZE_MAX) { 283 error = EINVAL; 284 goto bad; 285 } 286 287 opt = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 288 opt->name = malloc(namelen, M_MOUNT, M_WAITOK); 289 opt->value = NULL; 290 opt->len = 0; 291 opt->pos = i / 2; 292 opt->seen = 0; 293 294 /* 295 * Do this early, so jumps to "bad" will free the current 296 * option. 297 */ 298 TAILQ_INSERT_TAIL(opts, opt, link); 299 300 if (auio->uio_segflg == UIO_SYSSPACE) { 301 bcopy(auio->uio_iov[i].iov_base, opt->name, namelen); 302 } else { 303 error = copyin(auio->uio_iov[i].iov_base, opt->name, 304 namelen); 305 if (error) 306 goto bad; 307 } 308 /* Ensure names are null-terminated strings. */ 309 if (namelen == 0 || opt->name[namelen - 1] != '\0') { 310 error = EINVAL; 311 goto bad; 312 } 313 if (optlen != 0) { 314 opt->len = optlen; 315 opt->value = malloc(optlen, M_MOUNT, M_WAITOK); 316 if (auio->uio_segflg == UIO_SYSSPACE) { 317 bcopy(auio->uio_iov[i + 1].iov_base, opt->value, 318 optlen); 319 } else { 320 error = copyin(auio->uio_iov[i + 1].iov_base, 321 opt->value, optlen); 322 if (error) 323 goto bad; 324 } 325 } 326 } 327 vfs_sanitizeopts(opts); 328 *options = opts; 329 return (0); 330 bad: 331 vfs_freeopts(opts); 332 return (error); 333 } 334 335 /* 336 * Merge the old mount options with the new ones passed 337 * in the MNT_UPDATE case. 338 * 339 * XXX: This function will keep a "nofoo" option in the new 340 * options. E.g, if the option's canonical name is "foo", 341 * "nofoo" ends up in the mount point's active options. 342 */ 343 static void 344 vfs_mergeopts(struct vfsoptlist *toopts, struct vfsoptlist *oldopts) 345 { 346 struct vfsopt *opt, *new; 347 348 TAILQ_FOREACH(opt, oldopts, link) { 349 new = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 350 new->name = strdup(opt->name, M_MOUNT); 351 if (opt->len != 0) { 352 new->value = malloc(opt->len, M_MOUNT, M_WAITOK); 353 bcopy(opt->value, new->value, opt->len); 354 } else 355 new->value = NULL; 356 new->len = opt->len; 357 new->seen = opt->seen; 358 TAILQ_INSERT_HEAD(toopts, new, link); 359 } 360 vfs_sanitizeopts(toopts); 361 } 362 363 /* 364 * Mount a filesystem. 365 */ 366 int 367 sys_nmount(td, uap) 368 struct thread *td; 369 struct nmount_args /* { 370 struct iovec *iovp; 371 unsigned int iovcnt; 372 int flags; 373 } */ *uap; 374 { 375 struct uio *auio; 376 int error; 377 u_int iovcnt; 378 uint64_t flags; 379 380 /* 381 * Mount flags are now 64-bits. On 32-bit archtectures only 382 * 32-bits are passed in, but from here on everything handles 383 * 64-bit flags correctly. 384 */ 385 flags = uap->flags; 386 387 AUDIT_ARG_FFLAGS(flags); 388 CTR4(KTR_VFS, "%s: iovp %p with iovcnt %d and flags %d", __func__, 389 uap->iovp, uap->iovcnt, flags); 390 391 /* 392 * Filter out MNT_ROOTFS. We do not want clients of nmount() in 393 * userspace to set this flag, but we must filter it out if we want 394 * MNT_UPDATE on the root file system to work. 395 * MNT_ROOTFS should only be set by the kernel when mounting its 396 * root file system. 397 */ 398 flags &= ~MNT_ROOTFS; 399 400 iovcnt = uap->iovcnt; 401 /* 402 * Check that we have an even number of iovec's 403 * and that we have at least two options. 404 */ 405 if ((iovcnt & 1) || (iovcnt < 4)) { 406 CTR2(KTR_VFS, "%s: failed for invalid iovcnt %d", __func__, 407 uap->iovcnt); 408 return (EINVAL); 409 } 410 411 error = copyinuio(uap->iovp, iovcnt, &auio); 412 if (error) { 413 CTR2(KTR_VFS, "%s: failed for invalid uio op with %d errno", 414 __func__, error); 415 return (error); 416 } 417 error = vfs_donmount(td, flags, auio); 418 419 free(auio, M_IOV); 420 return (error); 421 } 422 423 /* 424 * --------------------------------------------------------------------- 425 * Various utility functions 426 */ 427 428 void 429 vfs_ref(struct mount *mp) 430 { 431 432 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 433 MNT_ILOCK(mp); 434 MNT_REF(mp); 435 MNT_IUNLOCK(mp); 436 } 437 438 void 439 vfs_rel(struct mount *mp) 440 { 441 442 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 443 MNT_ILOCK(mp); 444 MNT_REL(mp); 445 MNT_IUNLOCK(mp); 446 } 447 448 /* 449 * Allocate and initialize the mount point struct. 450 */ 451 struct mount * 452 vfs_mount_alloc(struct vnode *vp, struct vfsconf *vfsp, const char *fspath, 453 struct ucred *cred) 454 { 455 struct mount *mp; 456 457 mp = uma_zalloc(mount_zone, M_WAITOK); 458 bzero(&mp->mnt_startzero, 459 __rangeof(struct mount, mnt_startzero, mnt_endzero)); 460 TAILQ_INIT(&mp->mnt_nvnodelist); 461 mp->mnt_nvnodelistsize = 0; 462 TAILQ_INIT(&mp->mnt_activevnodelist); 463 mp->mnt_activevnodelistsize = 0; 464 mp->mnt_ref = 0; 465 (void) vfs_busy(mp, MBF_NOWAIT); 466 atomic_add_acq_int(&vfsp->vfc_refcount, 1); 467 mp->mnt_op = vfsp->vfc_vfsops; 468 mp->mnt_vfc = vfsp; 469 mp->mnt_stat.f_type = vfsp->vfc_typenum; 470 mp->mnt_gen++; 471 strlcpy(mp->mnt_stat.f_fstypename, vfsp->vfc_name, MFSNAMELEN); 472 mp->mnt_vnodecovered = vp; 473 mp->mnt_cred = crdup(cred); 474 mp->mnt_stat.f_owner = cred->cr_uid; 475 strlcpy(mp->mnt_stat.f_mntonname, fspath, MNAMELEN); 476 mp->mnt_iosize_max = DFLTPHYS; 477 #ifdef MAC 478 mac_mount_init(mp); 479 mac_mount_create(cred, mp); 480 #endif 481 arc4rand(&mp->mnt_hashseed, sizeof mp->mnt_hashseed, 0); 482 TAILQ_INIT(&mp->mnt_uppers); 483 return (mp); 484 } 485 486 /* 487 * Destroy the mount struct previously allocated by vfs_mount_alloc(). 488 */ 489 void 490 vfs_mount_destroy(struct mount *mp) 491 { 492 493 MNT_ILOCK(mp); 494 mp->mnt_kern_flag |= MNTK_REFEXPIRE; 495 if (mp->mnt_kern_flag & MNTK_MWAIT) { 496 mp->mnt_kern_flag &= ~MNTK_MWAIT; 497 wakeup(mp); 498 } 499 while (mp->mnt_ref) 500 msleep(mp, MNT_MTX(mp), PVFS, "mntref", 0); 501 KASSERT(mp->mnt_ref == 0, 502 ("%s: invalid refcount in the drain path @ %s:%d", __func__, 503 __FILE__, __LINE__)); 504 if (mp->mnt_writeopcount != 0) 505 panic("vfs_mount_destroy: nonzero writeopcount"); 506 if (mp->mnt_secondary_writes != 0) 507 panic("vfs_mount_destroy: nonzero secondary_writes"); 508 atomic_subtract_rel_int(&mp->mnt_vfc->vfc_refcount, 1); 509 if (!TAILQ_EMPTY(&mp->mnt_nvnodelist)) { 510 struct vnode *vp; 511 512 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) 513 vprint("", vp); 514 panic("unmount: dangling vnode"); 515 } 516 KASSERT(TAILQ_EMPTY(&mp->mnt_uppers), ("mnt_uppers")); 517 if (mp->mnt_nvnodelistsize != 0) 518 panic("vfs_mount_destroy: nonzero nvnodelistsize"); 519 if (mp->mnt_activevnodelistsize != 0) 520 panic("vfs_mount_destroy: nonzero activevnodelistsize"); 521 if (mp->mnt_lockref != 0) 522 panic("vfs_mount_destroy: nonzero lock refcount"); 523 MNT_IUNLOCK(mp); 524 #ifdef MAC 525 mac_mount_destroy(mp); 526 #endif 527 if (mp->mnt_opt != NULL) 528 vfs_freeopts(mp->mnt_opt); 529 crfree(mp->mnt_cred); 530 uma_zfree(mount_zone, mp); 531 } 532 533 int 534 vfs_donmount(struct thread *td, uint64_t fsflags, struct uio *fsoptions) 535 { 536 struct vfsoptlist *optlist; 537 struct vfsopt *opt, *tmp_opt; 538 char *fstype, *fspath, *errmsg; 539 int error, fstypelen, fspathlen, errmsg_len, errmsg_pos; 540 541 errmsg = fspath = NULL; 542 errmsg_len = fspathlen = 0; 543 errmsg_pos = -1; 544 545 error = vfs_buildopts(fsoptions, &optlist); 546 if (error) 547 return (error); 548 549 if (vfs_getopt(optlist, "errmsg", (void **)&errmsg, &errmsg_len) == 0) 550 errmsg_pos = vfs_getopt_pos(optlist, "errmsg"); 551 552 /* 553 * We need these two options before the others, 554 * and they are mandatory for any filesystem. 555 * Ensure they are NUL terminated as well. 556 */ 557 fstypelen = 0; 558 error = vfs_getopt(optlist, "fstype", (void **)&fstype, &fstypelen); 559 if (error || fstype[fstypelen - 1] != '\0') { 560 error = EINVAL; 561 if (errmsg != NULL) 562 strncpy(errmsg, "Invalid fstype", errmsg_len); 563 goto bail; 564 } 565 fspathlen = 0; 566 error = vfs_getopt(optlist, "fspath", (void **)&fspath, &fspathlen); 567 if (error || fspath[fspathlen - 1] != '\0') { 568 error = EINVAL; 569 if (errmsg != NULL) 570 strncpy(errmsg, "Invalid fspath", errmsg_len); 571 goto bail; 572 } 573 574 /* 575 * We need to see if we have the "update" option 576 * before we call vfs_domount(), since vfs_domount() has special 577 * logic based on MNT_UPDATE. This is very important 578 * when we want to update the root filesystem. 579 */ 580 TAILQ_FOREACH_SAFE(opt, optlist, link, tmp_opt) { 581 if (strcmp(opt->name, "update") == 0) { 582 fsflags |= MNT_UPDATE; 583 vfs_freeopt(optlist, opt); 584 } 585 else if (strcmp(opt->name, "async") == 0) 586 fsflags |= MNT_ASYNC; 587 else if (strcmp(opt->name, "force") == 0) { 588 fsflags |= MNT_FORCE; 589 vfs_freeopt(optlist, opt); 590 } 591 else if (strcmp(opt->name, "reload") == 0) { 592 fsflags |= MNT_RELOAD; 593 vfs_freeopt(optlist, opt); 594 } 595 else if (strcmp(opt->name, "multilabel") == 0) 596 fsflags |= MNT_MULTILABEL; 597 else if (strcmp(opt->name, "noasync") == 0) 598 fsflags &= ~MNT_ASYNC; 599 else if (strcmp(opt->name, "noatime") == 0) 600 fsflags |= MNT_NOATIME; 601 else if (strcmp(opt->name, "atime") == 0) { 602 free(opt->name, M_MOUNT); 603 opt->name = strdup("nonoatime", M_MOUNT); 604 } 605 else if (strcmp(opt->name, "noclusterr") == 0) 606 fsflags |= MNT_NOCLUSTERR; 607 else if (strcmp(opt->name, "clusterr") == 0) { 608 free(opt->name, M_MOUNT); 609 opt->name = strdup("nonoclusterr", M_MOUNT); 610 } 611 else if (strcmp(opt->name, "noclusterw") == 0) 612 fsflags |= MNT_NOCLUSTERW; 613 else if (strcmp(opt->name, "clusterw") == 0) { 614 free(opt->name, M_MOUNT); 615 opt->name = strdup("nonoclusterw", M_MOUNT); 616 } 617 else if (strcmp(opt->name, "noexec") == 0) 618 fsflags |= MNT_NOEXEC; 619 else if (strcmp(opt->name, "exec") == 0) { 620 free(opt->name, M_MOUNT); 621 opt->name = strdup("nonoexec", M_MOUNT); 622 } 623 else if (strcmp(opt->name, "nosuid") == 0) 624 fsflags |= MNT_NOSUID; 625 else if (strcmp(opt->name, "suid") == 0) { 626 free(opt->name, M_MOUNT); 627 opt->name = strdup("nonosuid", M_MOUNT); 628 } 629 else if (strcmp(opt->name, "nosymfollow") == 0) 630 fsflags |= MNT_NOSYMFOLLOW; 631 else if (strcmp(opt->name, "symfollow") == 0) { 632 free(opt->name, M_MOUNT); 633 opt->name = strdup("nonosymfollow", M_MOUNT); 634 } 635 else if (strcmp(opt->name, "noro") == 0) 636 fsflags &= ~MNT_RDONLY; 637 else if (strcmp(opt->name, "rw") == 0) 638 fsflags &= ~MNT_RDONLY; 639 else if (strcmp(opt->name, "ro") == 0) 640 fsflags |= MNT_RDONLY; 641 else if (strcmp(opt->name, "rdonly") == 0) { 642 free(opt->name, M_MOUNT); 643 opt->name = strdup("ro", M_MOUNT); 644 fsflags |= MNT_RDONLY; 645 } 646 else if (strcmp(opt->name, "suiddir") == 0) 647 fsflags |= MNT_SUIDDIR; 648 else if (strcmp(opt->name, "sync") == 0) 649 fsflags |= MNT_SYNCHRONOUS; 650 else if (strcmp(opt->name, "union") == 0) 651 fsflags |= MNT_UNION; 652 else if (strcmp(opt->name, "automounted") == 0) { 653 fsflags |= MNT_AUTOMOUNTED; 654 vfs_freeopt(optlist, opt); 655 } 656 } 657 658 /* 659 * Be ultra-paranoid about making sure the type and fspath 660 * variables will fit in our mp buffers, including the 661 * terminating NUL. 662 */ 663 if (fstypelen > MFSNAMELEN || fspathlen > MNAMELEN) { 664 error = ENAMETOOLONG; 665 goto bail; 666 } 667 668 error = vfs_domount(td, fstype, fspath, fsflags, &optlist); 669 bail: 670 /* copyout the errmsg */ 671 if (errmsg_pos != -1 && ((2 * errmsg_pos + 1) < fsoptions->uio_iovcnt) 672 && errmsg_len > 0 && errmsg != NULL) { 673 if (fsoptions->uio_segflg == UIO_SYSSPACE) { 674 bcopy(errmsg, 675 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_base, 676 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_len); 677 } else { 678 copyout(errmsg, 679 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_base, 680 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_len); 681 } 682 } 683 684 if (optlist != NULL) 685 vfs_freeopts(optlist); 686 return (error); 687 } 688 689 /* 690 * Old mount API. 691 */ 692 #ifndef _SYS_SYSPROTO_H_ 693 struct mount_args { 694 char *type; 695 char *path; 696 int flags; 697 caddr_t data; 698 }; 699 #endif 700 /* ARGSUSED */ 701 int 702 sys_mount(td, uap) 703 struct thread *td; 704 struct mount_args /* { 705 char *type; 706 char *path; 707 int flags; 708 caddr_t data; 709 } */ *uap; 710 { 711 char *fstype; 712 struct vfsconf *vfsp = NULL; 713 struct mntarg *ma = NULL; 714 uint64_t flags; 715 int error; 716 717 /* 718 * Mount flags are now 64-bits. On 32-bit architectures only 719 * 32-bits are passed in, but from here on everything handles 720 * 64-bit flags correctly. 721 */ 722 flags = uap->flags; 723 724 AUDIT_ARG_FFLAGS(flags); 725 726 /* 727 * Filter out MNT_ROOTFS. We do not want clients of mount() in 728 * userspace to set this flag, but we must filter it out if we want 729 * MNT_UPDATE on the root file system to work. 730 * MNT_ROOTFS should only be set by the kernel when mounting its 731 * root file system. 732 */ 733 flags &= ~MNT_ROOTFS; 734 735 fstype = malloc(MFSNAMELEN, M_TEMP, M_WAITOK); 736 error = copyinstr(uap->type, fstype, MFSNAMELEN, NULL); 737 if (error) { 738 free(fstype, M_TEMP); 739 return (error); 740 } 741 742 AUDIT_ARG_TEXT(fstype); 743 vfsp = vfs_byname_kld(fstype, td, &error); 744 free(fstype, M_TEMP); 745 if (vfsp == NULL) 746 return (ENOENT); 747 if (vfsp->vfc_vfsops->vfs_cmount == NULL) 748 return (EOPNOTSUPP); 749 750 ma = mount_argsu(ma, "fstype", uap->type, MFSNAMELEN); 751 ma = mount_argsu(ma, "fspath", uap->path, MNAMELEN); 752 ma = mount_argb(ma, flags & MNT_RDONLY, "noro"); 753 ma = mount_argb(ma, !(flags & MNT_NOSUID), "nosuid"); 754 ma = mount_argb(ma, !(flags & MNT_NOEXEC), "noexec"); 755 756 error = vfsp->vfc_vfsops->vfs_cmount(ma, uap->data, flags); 757 return (error); 758 } 759 760 /* 761 * vfs_domount_first(): first file system mount (not update) 762 */ 763 static int 764 vfs_domount_first( 765 struct thread *td, /* Calling thread. */ 766 struct vfsconf *vfsp, /* File system type. */ 767 char *fspath, /* Mount path. */ 768 struct vnode *vp, /* Vnode to be covered. */ 769 uint64_t fsflags, /* Flags common to all filesystems. */ 770 struct vfsoptlist **optlist /* Options local to the filesystem. */ 771 ) 772 { 773 struct vattr va; 774 struct mount *mp; 775 struct vnode *newdp; 776 int error; 777 778 ASSERT_VOP_ELOCKED(vp, __func__); 779 KASSERT((fsflags & MNT_UPDATE) == 0, ("MNT_UPDATE shouldn't be here")); 780 781 /* 782 * If the user is not root, ensure that they own the directory 783 * onto which we are attempting to mount. 784 */ 785 error = VOP_GETATTR(vp, &va, td->td_ucred); 786 if (error == 0 && va.va_uid != td->td_ucred->cr_uid) 787 error = priv_check_cred(td->td_ucred, PRIV_VFS_ADMIN, 0); 788 if (error == 0) 789 error = vinvalbuf(vp, V_SAVE, 0, 0); 790 if (error == 0 && vp->v_type != VDIR) 791 error = ENOTDIR; 792 if (error == 0) { 793 VI_LOCK(vp); 794 if ((vp->v_iflag & VI_MOUNT) == 0 && vp->v_mountedhere == NULL) 795 vp->v_iflag |= VI_MOUNT; 796 else 797 error = EBUSY; 798 VI_UNLOCK(vp); 799 } 800 if (error != 0) { 801 vput(vp); 802 return (error); 803 } 804 VOP_UNLOCK(vp, 0); 805 806 /* Allocate and initialize the filesystem. */ 807 mp = vfs_mount_alloc(vp, vfsp, fspath, td->td_ucred); 808 /* XXXMAC: pass to vfs_mount_alloc? */ 809 mp->mnt_optnew = *optlist; 810 /* Set the mount level flags. */ 811 mp->mnt_flag = (fsflags & (MNT_UPDATEMASK | MNT_ROOTFS | MNT_RDONLY)); 812 813 /* 814 * Mount the filesystem. 815 * XXX The final recipients of VFS_MOUNT just overwrite the ndp they 816 * get. No freeing of cn_pnbuf. 817 */ 818 error = VFS_MOUNT(mp); 819 if (error != 0) { 820 vfs_unbusy(mp); 821 vfs_mount_destroy(mp); 822 VI_LOCK(vp); 823 vp->v_iflag &= ~VI_MOUNT; 824 VI_UNLOCK(vp); 825 vrele(vp); 826 return (error); 827 } 828 829 if (mp->mnt_opt != NULL) 830 vfs_freeopts(mp->mnt_opt); 831 mp->mnt_opt = mp->mnt_optnew; 832 *optlist = NULL; 833 (void)VFS_STATFS(mp, &mp->mnt_stat); 834 835 /* 836 * Prevent external consumers of mount options from reading mnt_optnew. 837 */ 838 mp->mnt_optnew = NULL; 839 840 MNT_ILOCK(mp); 841 if ((mp->mnt_flag & MNT_ASYNC) != 0 && 842 (mp->mnt_kern_flag & MNTK_NOASYNC) == 0) 843 mp->mnt_kern_flag |= MNTK_ASYNC; 844 else 845 mp->mnt_kern_flag &= ~MNTK_ASYNC; 846 MNT_IUNLOCK(mp); 847 848 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 849 cache_purge(vp); 850 VI_LOCK(vp); 851 vp->v_iflag &= ~VI_MOUNT; 852 VI_UNLOCK(vp); 853 vp->v_mountedhere = mp; 854 /* Place the new filesystem at the end of the mount list. */ 855 mtx_lock(&mountlist_mtx); 856 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 857 mtx_unlock(&mountlist_mtx); 858 vfs_event_signal(NULL, VQ_MOUNT, 0); 859 if (VFS_ROOT(mp, LK_EXCLUSIVE, &newdp)) 860 panic("mount: lost mount"); 861 VOP_UNLOCK(vp, 0); 862 EVENTHANDLER_INVOKE(vfs_mounted, mp, newdp, td); 863 VOP_UNLOCK(newdp, 0); 864 mountcheckdirs(vp, newdp); 865 vrele(newdp); 866 if ((mp->mnt_flag & MNT_RDONLY) == 0) 867 vfs_allocate_syncvnode(mp); 868 vfs_unbusy(mp); 869 return (0); 870 } 871 872 /* 873 * vfs_domount_update(): update of mounted file system 874 */ 875 static int 876 vfs_domount_update( 877 struct thread *td, /* Calling thread. */ 878 struct vnode *vp, /* Mount point vnode. */ 879 uint64_t fsflags, /* Flags common to all filesystems. */ 880 struct vfsoptlist **optlist /* Options local to the filesystem. */ 881 ) 882 { 883 struct export_args export; 884 void *bufp; 885 struct mount *mp; 886 int error, export_error, len; 887 uint64_t flag; 888 889 ASSERT_VOP_ELOCKED(vp, __func__); 890 KASSERT((fsflags & MNT_UPDATE) != 0, ("MNT_UPDATE should be here")); 891 mp = vp->v_mount; 892 893 if ((vp->v_vflag & VV_ROOT) == 0) { 894 if (vfs_copyopt(*optlist, "export", &export, sizeof(export)) 895 == 0) 896 error = EXDEV; 897 else 898 error = EINVAL; 899 vput(vp); 900 return (error); 901 } 902 903 /* 904 * We only allow the filesystem to be reloaded if it 905 * is currently mounted read-only. 906 */ 907 flag = mp->mnt_flag; 908 if ((fsflags & MNT_RELOAD) != 0 && (flag & MNT_RDONLY) == 0) { 909 vput(vp); 910 return (EOPNOTSUPP); /* Needs translation */ 911 } 912 /* 913 * Only privileged root, or (if MNT_USER is set) the user that 914 * did the original mount is permitted to update it. 915 */ 916 error = vfs_suser(mp, td); 917 if (error != 0) { 918 vput(vp); 919 return (error); 920 } 921 if (vfs_busy(mp, MBF_NOWAIT)) { 922 vput(vp); 923 return (EBUSY); 924 } 925 VI_LOCK(vp); 926 if ((vp->v_iflag & VI_MOUNT) != 0 || vp->v_mountedhere != NULL) { 927 VI_UNLOCK(vp); 928 vfs_unbusy(mp); 929 vput(vp); 930 return (EBUSY); 931 } 932 vp->v_iflag |= VI_MOUNT; 933 VI_UNLOCK(vp); 934 VOP_UNLOCK(vp, 0); 935 936 MNT_ILOCK(mp); 937 mp->mnt_flag &= ~MNT_UPDATEMASK; 938 mp->mnt_flag |= fsflags & (MNT_RELOAD | MNT_FORCE | MNT_UPDATE | 939 MNT_SNAPSHOT | MNT_ROOTFS | MNT_UPDATEMASK | MNT_RDONLY); 940 if ((mp->mnt_flag & MNT_ASYNC) == 0) 941 mp->mnt_kern_flag &= ~MNTK_ASYNC; 942 MNT_IUNLOCK(mp); 943 mp->mnt_optnew = *optlist; 944 vfs_mergeopts(mp->mnt_optnew, mp->mnt_opt); 945 946 /* 947 * Mount the filesystem. 948 * XXX The final recipients of VFS_MOUNT just overwrite the ndp they 949 * get. No freeing of cn_pnbuf. 950 */ 951 error = VFS_MOUNT(mp); 952 953 export_error = 0; 954 /* Process the export option. */ 955 if (error == 0 && vfs_getopt(mp->mnt_optnew, "export", &bufp, 956 &len) == 0) { 957 /* Assume that there is only 1 ABI for each length. */ 958 switch (len) { 959 case (sizeof(struct oexport_args)): 960 bzero(&export, sizeof(export)); 961 /* FALLTHROUGH */ 962 case (sizeof(export)): 963 bcopy(bufp, &export, len); 964 export_error = vfs_export(mp, &export); 965 break; 966 default: 967 export_error = EINVAL; 968 break; 969 } 970 } 971 972 MNT_ILOCK(mp); 973 if (error == 0) { 974 mp->mnt_flag &= ~(MNT_UPDATE | MNT_RELOAD | MNT_FORCE | 975 MNT_SNAPSHOT); 976 } else { 977 /* 978 * If we fail, restore old mount flags. MNT_QUOTA is special, 979 * because it is not part of MNT_UPDATEMASK, but it could have 980 * changed in the meantime if quotactl(2) was called. 981 * All in all we want current value of MNT_QUOTA, not the old 982 * one. 983 */ 984 mp->mnt_flag = (mp->mnt_flag & MNT_QUOTA) | (flag & ~MNT_QUOTA); 985 } 986 if ((mp->mnt_flag & MNT_ASYNC) != 0 && 987 (mp->mnt_kern_flag & MNTK_NOASYNC) == 0) 988 mp->mnt_kern_flag |= MNTK_ASYNC; 989 else 990 mp->mnt_kern_flag &= ~MNTK_ASYNC; 991 MNT_IUNLOCK(mp); 992 993 if (error != 0) 994 goto end; 995 996 if (mp->mnt_opt != NULL) 997 vfs_freeopts(mp->mnt_opt); 998 mp->mnt_opt = mp->mnt_optnew; 999 *optlist = NULL; 1000 (void)VFS_STATFS(mp, &mp->mnt_stat); 1001 /* 1002 * Prevent external consumers of mount options from reading 1003 * mnt_optnew. 1004 */ 1005 mp->mnt_optnew = NULL; 1006 1007 if ((mp->mnt_flag & MNT_RDONLY) == 0) 1008 vfs_allocate_syncvnode(mp); 1009 else 1010 vfs_deallocate_syncvnode(mp); 1011 end: 1012 vfs_unbusy(mp); 1013 VI_LOCK(vp); 1014 vp->v_iflag &= ~VI_MOUNT; 1015 VI_UNLOCK(vp); 1016 vrele(vp); 1017 return (error != 0 ? error : export_error); 1018 } 1019 1020 /* 1021 * vfs_domount(): actually attempt a filesystem mount. 1022 */ 1023 static int 1024 vfs_domount( 1025 struct thread *td, /* Calling thread. */ 1026 const char *fstype, /* Filesystem type. */ 1027 char *fspath, /* Mount path. */ 1028 uint64_t fsflags, /* Flags common to all filesystems. */ 1029 struct vfsoptlist **optlist /* Options local to the filesystem. */ 1030 ) 1031 { 1032 struct vfsconf *vfsp; 1033 struct nameidata nd; 1034 struct vnode *vp; 1035 char *pathbuf; 1036 int error; 1037 1038 /* 1039 * Be ultra-paranoid about making sure the type and fspath 1040 * variables will fit in our mp buffers, including the 1041 * terminating NUL. 1042 */ 1043 if (strlen(fstype) >= MFSNAMELEN || strlen(fspath) >= MNAMELEN) 1044 return (ENAMETOOLONG); 1045 1046 if (jailed(td->td_ucred) || usermount == 0) { 1047 if ((error = priv_check(td, PRIV_VFS_MOUNT)) != 0) 1048 return (error); 1049 } 1050 1051 /* 1052 * Do not allow NFS export or MNT_SUIDDIR by unprivileged users. 1053 */ 1054 if (fsflags & MNT_EXPORTED) { 1055 error = priv_check(td, PRIV_VFS_MOUNT_EXPORTED); 1056 if (error) 1057 return (error); 1058 } 1059 if (fsflags & MNT_SUIDDIR) { 1060 error = priv_check(td, PRIV_VFS_MOUNT_SUIDDIR); 1061 if (error) 1062 return (error); 1063 } 1064 /* 1065 * Silently enforce MNT_NOSUID and MNT_USER for unprivileged users. 1066 */ 1067 if ((fsflags & (MNT_NOSUID | MNT_USER)) != (MNT_NOSUID | MNT_USER)) { 1068 if (priv_check(td, PRIV_VFS_MOUNT_NONUSER) != 0) 1069 fsflags |= MNT_NOSUID | MNT_USER; 1070 } 1071 1072 /* Load KLDs before we lock the covered vnode to avoid reversals. */ 1073 vfsp = NULL; 1074 if ((fsflags & MNT_UPDATE) == 0) { 1075 /* Don't try to load KLDs if we're mounting the root. */ 1076 if (fsflags & MNT_ROOTFS) 1077 vfsp = vfs_byname(fstype); 1078 else 1079 vfsp = vfs_byname_kld(fstype, td, &error); 1080 if (vfsp == NULL) 1081 return (ENODEV); 1082 if (jailed(td->td_ucred) && !(vfsp->vfc_flags & VFCF_JAIL)) 1083 return (EPERM); 1084 } 1085 1086 /* 1087 * Get vnode to be covered or mount point's vnode in case of MNT_UPDATE. 1088 */ 1089 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, 1090 UIO_SYSSPACE, fspath, td); 1091 error = namei(&nd); 1092 if (error != 0) 1093 return (error); 1094 NDFREE(&nd, NDF_ONLY_PNBUF); 1095 vp = nd.ni_vp; 1096 if ((fsflags & MNT_UPDATE) == 0) { 1097 pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK); 1098 strcpy(pathbuf, fspath); 1099 error = vn_path_to_global_path(td, vp, pathbuf, MNAMELEN); 1100 /* debug.disablefullpath == 1 results in ENODEV */ 1101 if (error == 0 || error == ENODEV) { 1102 error = vfs_domount_first(td, vfsp, pathbuf, vp, 1103 fsflags, optlist); 1104 } 1105 free(pathbuf, M_TEMP); 1106 } else 1107 error = vfs_domount_update(td, vp, fsflags, optlist); 1108 1109 return (error); 1110 } 1111 1112 /* 1113 * Unmount a filesystem. 1114 * 1115 * Note: unmount takes a path to the vnode mounted on as argument, not 1116 * special file (as before). 1117 */ 1118 #ifndef _SYS_SYSPROTO_H_ 1119 struct unmount_args { 1120 char *path; 1121 int flags; 1122 }; 1123 #endif 1124 /* ARGSUSED */ 1125 int 1126 sys_unmount(struct thread *td, struct unmount_args *uap) 1127 { 1128 struct nameidata nd; 1129 struct mount *mp; 1130 char *pathbuf; 1131 int error, id0, id1; 1132 1133 AUDIT_ARG_VALUE(uap->flags); 1134 if (jailed(td->td_ucred) || usermount == 0) { 1135 error = priv_check(td, PRIV_VFS_UNMOUNT); 1136 if (error) 1137 return (error); 1138 } 1139 1140 pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK); 1141 error = copyinstr(uap->path, pathbuf, MNAMELEN, NULL); 1142 if (error) { 1143 free(pathbuf, M_TEMP); 1144 return (error); 1145 } 1146 if (uap->flags & MNT_BYFSID) { 1147 AUDIT_ARG_TEXT(pathbuf); 1148 /* Decode the filesystem ID. */ 1149 if (sscanf(pathbuf, "FSID:%d:%d", &id0, &id1) != 2) { 1150 free(pathbuf, M_TEMP); 1151 return (EINVAL); 1152 } 1153 1154 mtx_lock(&mountlist_mtx); 1155 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1156 if (mp->mnt_stat.f_fsid.val[0] == id0 && 1157 mp->mnt_stat.f_fsid.val[1] == id1) { 1158 vfs_ref(mp); 1159 break; 1160 } 1161 } 1162 mtx_unlock(&mountlist_mtx); 1163 } else { 1164 /* 1165 * Try to find global path for path argument. 1166 */ 1167 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, 1168 UIO_SYSSPACE, pathbuf, td); 1169 if (namei(&nd) == 0) { 1170 NDFREE(&nd, NDF_ONLY_PNBUF); 1171 error = vn_path_to_global_path(td, nd.ni_vp, pathbuf, 1172 MNAMELEN); 1173 if (error == 0 || error == ENODEV) 1174 vput(nd.ni_vp); 1175 } 1176 mtx_lock(&mountlist_mtx); 1177 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1178 if (strcmp(mp->mnt_stat.f_mntonname, pathbuf) == 0) { 1179 vfs_ref(mp); 1180 break; 1181 } 1182 } 1183 mtx_unlock(&mountlist_mtx); 1184 } 1185 free(pathbuf, M_TEMP); 1186 if (mp == NULL) { 1187 /* 1188 * Previously we returned ENOENT for a nonexistent path and 1189 * EINVAL for a non-mountpoint. We cannot tell these apart 1190 * now, so in the !MNT_BYFSID case return the more likely 1191 * EINVAL for compatibility. 1192 */ 1193 return ((uap->flags & MNT_BYFSID) ? ENOENT : EINVAL); 1194 } 1195 1196 /* 1197 * Don't allow unmounting the root filesystem. 1198 */ 1199 if (mp->mnt_flag & MNT_ROOTFS) { 1200 vfs_rel(mp); 1201 return (EINVAL); 1202 } 1203 error = dounmount(mp, uap->flags, td); 1204 return (error); 1205 } 1206 1207 /* 1208 * Do the actual filesystem unmount. 1209 */ 1210 int 1211 dounmount(struct mount *mp, int flags, struct thread *td) 1212 { 1213 struct vnode *coveredvp, *fsrootvp; 1214 int error; 1215 uint64_t async_flag; 1216 int mnt_gen_r; 1217 1218 if ((coveredvp = mp->mnt_vnodecovered) != NULL) { 1219 mnt_gen_r = mp->mnt_gen; 1220 VI_LOCK(coveredvp); 1221 vholdl(coveredvp); 1222 vn_lock(coveredvp, LK_EXCLUSIVE | LK_INTERLOCK | LK_RETRY); 1223 /* 1224 * Check for mp being unmounted while waiting for the 1225 * covered vnode lock. 1226 */ 1227 if (coveredvp->v_mountedhere != mp || 1228 coveredvp->v_mountedhere->mnt_gen != mnt_gen_r) { 1229 VOP_UNLOCK(coveredvp, 0); 1230 vdrop(coveredvp); 1231 vfs_rel(mp); 1232 return (EBUSY); 1233 } 1234 } 1235 1236 /* 1237 * Only privileged root, or (if MNT_USER is set) the user that did the 1238 * original mount is permitted to unmount this filesystem. 1239 */ 1240 error = vfs_suser(mp, td); 1241 if (error != 0) { 1242 if (coveredvp != NULL) { 1243 VOP_UNLOCK(coveredvp, 0); 1244 vdrop(coveredvp); 1245 } 1246 vfs_rel(mp); 1247 return (error); 1248 } 1249 1250 vn_start_write(NULL, &mp, V_WAIT | V_MNTREF); 1251 MNT_ILOCK(mp); 1252 if ((mp->mnt_kern_flag & MNTK_UNMOUNT) != 0 || 1253 !TAILQ_EMPTY(&mp->mnt_uppers)) { 1254 MNT_IUNLOCK(mp); 1255 if (coveredvp != NULL) { 1256 VOP_UNLOCK(coveredvp, 0); 1257 vdrop(coveredvp); 1258 } 1259 vn_finished_write(mp); 1260 return (EBUSY); 1261 } 1262 mp->mnt_kern_flag |= MNTK_UNMOUNT | MNTK_NOINSMNTQ; 1263 /* Allow filesystems to detect that a forced unmount is in progress. */ 1264 if (flags & MNT_FORCE) { 1265 mp->mnt_kern_flag |= MNTK_UNMOUNTF; 1266 MNT_IUNLOCK(mp); 1267 /* 1268 * Must be done after setting MNTK_UNMOUNTF and before 1269 * waiting for mnt_lockref to become 0. 1270 */ 1271 VFS_PURGE(mp); 1272 MNT_ILOCK(mp); 1273 } 1274 error = 0; 1275 if (mp->mnt_lockref) { 1276 mp->mnt_kern_flag |= MNTK_DRAINING; 1277 error = msleep(&mp->mnt_lockref, MNT_MTX(mp), PVFS, 1278 "mount drain", 0); 1279 } 1280 MNT_IUNLOCK(mp); 1281 KASSERT(mp->mnt_lockref == 0, 1282 ("%s: invalid lock refcount in the drain path @ %s:%d", 1283 __func__, __FILE__, __LINE__)); 1284 KASSERT(error == 0, 1285 ("%s: invalid return value for msleep in the drain path @ %s:%d", 1286 __func__, __FILE__, __LINE__)); 1287 1288 if (mp->mnt_flag & MNT_EXPUBLIC) 1289 vfs_setpublicfs(NULL, NULL, NULL); 1290 1291 /* 1292 * From now, we can claim that the use reference on the 1293 * coveredvp is ours, and the ref can be released only by 1294 * successfull unmount by us, or left for later unmount 1295 * attempt. The previously acquired hold reference is no 1296 * longer needed to protect the vnode from reuse. 1297 */ 1298 if (coveredvp != NULL) 1299 vdrop(coveredvp); 1300 1301 vfs_msync(mp, MNT_WAIT); 1302 MNT_ILOCK(mp); 1303 async_flag = mp->mnt_flag & MNT_ASYNC; 1304 mp->mnt_flag &= ~MNT_ASYNC; 1305 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1306 MNT_IUNLOCK(mp); 1307 cache_purgevfs(mp); /* remove cache entries for this file sys */ 1308 vfs_deallocate_syncvnode(mp); 1309 /* 1310 * For forced unmounts, move process cdir/rdir refs on the fs root 1311 * vnode to the covered vnode. For non-forced unmounts we want 1312 * such references to cause an EBUSY error. 1313 */ 1314 if ((flags & MNT_FORCE) && 1315 VFS_ROOT(mp, LK_EXCLUSIVE, &fsrootvp) == 0) { 1316 if (mp->mnt_vnodecovered != NULL && 1317 (mp->mnt_flag & MNT_IGNORE) == 0) 1318 mountcheckdirs(fsrootvp, mp->mnt_vnodecovered); 1319 if (fsrootvp == rootvnode) { 1320 vrele(rootvnode); 1321 rootvnode = NULL; 1322 } 1323 vput(fsrootvp); 1324 } 1325 if ((mp->mnt_flag & MNT_RDONLY) != 0 || (flags & MNT_FORCE) != 0 || 1326 (error = VFS_SYNC(mp, MNT_WAIT)) == 0) 1327 error = VFS_UNMOUNT(mp, flags); 1328 vn_finished_write(mp); 1329 /* 1330 * If we failed to flush the dirty blocks for this mount point, 1331 * undo all the cdir/rdir and rootvnode changes we made above. 1332 * Unless we failed to do so because the device is reporting that 1333 * it doesn't exist anymore. 1334 */ 1335 if (error && error != ENXIO) { 1336 if ((flags & MNT_FORCE) && 1337 VFS_ROOT(mp, LK_EXCLUSIVE, &fsrootvp) == 0) { 1338 if (mp->mnt_vnodecovered != NULL && 1339 (mp->mnt_flag & MNT_IGNORE) == 0) 1340 mountcheckdirs(mp->mnt_vnodecovered, fsrootvp); 1341 if (rootvnode == NULL) { 1342 rootvnode = fsrootvp; 1343 vref(rootvnode); 1344 } 1345 vput(fsrootvp); 1346 } 1347 MNT_ILOCK(mp); 1348 mp->mnt_kern_flag &= ~MNTK_NOINSMNTQ; 1349 if ((mp->mnt_flag & MNT_RDONLY) == 0) { 1350 MNT_IUNLOCK(mp); 1351 vfs_allocate_syncvnode(mp); 1352 MNT_ILOCK(mp); 1353 } 1354 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 1355 mp->mnt_flag |= async_flag; 1356 if ((mp->mnt_flag & MNT_ASYNC) != 0 && 1357 (mp->mnt_kern_flag & MNTK_NOASYNC) == 0) 1358 mp->mnt_kern_flag |= MNTK_ASYNC; 1359 if (mp->mnt_kern_flag & MNTK_MWAIT) { 1360 mp->mnt_kern_flag &= ~MNTK_MWAIT; 1361 wakeup(mp); 1362 } 1363 MNT_IUNLOCK(mp); 1364 if (coveredvp) 1365 VOP_UNLOCK(coveredvp, 0); 1366 return (error); 1367 } 1368 mtx_lock(&mountlist_mtx); 1369 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1370 mtx_unlock(&mountlist_mtx); 1371 EVENTHANDLER_INVOKE(vfs_unmounted, mp, td); 1372 if (coveredvp != NULL) { 1373 coveredvp->v_mountedhere = NULL; 1374 vput(coveredvp); 1375 } 1376 vfs_event_signal(NULL, VQ_UNMOUNT, 0); 1377 if (mp == rootdevmp) 1378 rootdevmp = NULL; 1379 vfs_mount_destroy(mp); 1380 return (0); 1381 } 1382 1383 /* 1384 * Report errors during filesystem mounting. 1385 */ 1386 void 1387 vfs_mount_error(struct mount *mp, const char *fmt, ...) 1388 { 1389 struct vfsoptlist *moptlist = mp->mnt_optnew; 1390 va_list ap; 1391 int error, len; 1392 char *errmsg; 1393 1394 error = vfs_getopt(moptlist, "errmsg", (void **)&errmsg, &len); 1395 if (error || errmsg == NULL || len <= 0) 1396 return; 1397 1398 va_start(ap, fmt); 1399 vsnprintf(errmsg, (size_t)len, fmt, ap); 1400 va_end(ap); 1401 } 1402 1403 void 1404 vfs_opterror(struct vfsoptlist *opts, const char *fmt, ...) 1405 { 1406 va_list ap; 1407 int error, len; 1408 char *errmsg; 1409 1410 error = vfs_getopt(opts, "errmsg", (void **)&errmsg, &len); 1411 if (error || errmsg == NULL || len <= 0) 1412 return; 1413 1414 va_start(ap, fmt); 1415 vsnprintf(errmsg, (size_t)len, fmt, ap); 1416 va_end(ap); 1417 } 1418 1419 /* 1420 * --------------------------------------------------------------------- 1421 * Functions for querying mount options/arguments from filesystems. 1422 */ 1423 1424 /* 1425 * Check that no unknown options are given 1426 */ 1427 int 1428 vfs_filteropt(struct vfsoptlist *opts, const char **legal) 1429 { 1430 struct vfsopt *opt; 1431 char errmsg[255]; 1432 const char **t, *p, *q; 1433 int ret = 0; 1434 1435 TAILQ_FOREACH(opt, opts, link) { 1436 p = opt->name; 1437 q = NULL; 1438 if (p[0] == 'n' && p[1] == 'o') 1439 q = p + 2; 1440 for(t = global_opts; *t != NULL; t++) { 1441 if (strcmp(*t, p) == 0) 1442 break; 1443 if (q != NULL) { 1444 if (strcmp(*t, q) == 0) 1445 break; 1446 } 1447 } 1448 if (*t != NULL) 1449 continue; 1450 for(t = legal; *t != NULL; t++) { 1451 if (strcmp(*t, p) == 0) 1452 break; 1453 if (q != NULL) { 1454 if (strcmp(*t, q) == 0) 1455 break; 1456 } 1457 } 1458 if (*t != NULL) 1459 continue; 1460 snprintf(errmsg, sizeof(errmsg), 1461 "mount option <%s> is unknown", p); 1462 ret = EINVAL; 1463 } 1464 if (ret != 0) { 1465 TAILQ_FOREACH(opt, opts, link) { 1466 if (strcmp(opt->name, "errmsg") == 0) { 1467 strncpy((char *)opt->value, errmsg, opt->len); 1468 break; 1469 } 1470 } 1471 if (opt == NULL) 1472 printf("%s\n", errmsg); 1473 } 1474 return (ret); 1475 } 1476 1477 /* 1478 * Get a mount option by its name. 1479 * 1480 * Return 0 if the option was found, ENOENT otherwise. 1481 * If len is non-NULL it will be filled with the length 1482 * of the option. If buf is non-NULL, it will be filled 1483 * with the address of the option. 1484 */ 1485 int 1486 vfs_getopt(opts, name, buf, len) 1487 struct vfsoptlist *opts; 1488 const char *name; 1489 void **buf; 1490 int *len; 1491 { 1492 struct vfsopt *opt; 1493 1494 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1495 1496 TAILQ_FOREACH(opt, opts, link) { 1497 if (strcmp(name, opt->name) == 0) { 1498 opt->seen = 1; 1499 if (len != NULL) 1500 *len = opt->len; 1501 if (buf != NULL) 1502 *buf = opt->value; 1503 return (0); 1504 } 1505 } 1506 return (ENOENT); 1507 } 1508 1509 int 1510 vfs_getopt_pos(struct vfsoptlist *opts, const char *name) 1511 { 1512 struct vfsopt *opt; 1513 1514 if (opts == NULL) 1515 return (-1); 1516 1517 TAILQ_FOREACH(opt, opts, link) { 1518 if (strcmp(name, opt->name) == 0) { 1519 opt->seen = 1; 1520 return (opt->pos); 1521 } 1522 } 1523 return (-1); 1524 } 1525 1526 int 1527 vfs_getopt_size(struct vfsoptlist *opts, const char *name, off_t *value) 1528 { 1529 char *opt_value, *vtp; 1530 quad_t iv; 1531 int error, opt_len; 1532 1533 error = vfs_getopt(opts, name, (void **)&opt_value, &opt_len); 1534 if (error != 0) 1535 return (error); 1536 if (opt_len == 0 || opt_value == NULL) 1537 return (EINVAL); 1538 if (opt_value[0] == '\0' || opt_value[opt_len - 1] != '\0') 1539 return (EINVAL); 1540 iv = strtoq(opt_value, &vtp, 0); 1541 if (vtp == opt_value || (vtp[0] != '\0' && vtp[1] != '\0')) 1542 return (EINVAL); 1543 if (iv < 0) 1544 return (EINVAL); 1545 switch (vtp[0]) { 1546 case 't': 1547 case 'T': 1548 iv *= 1024; 1549 case 'g': 1550 case 'G': 1551 iv *= 1024; 1552 case 'm': 1553 case 'M': 1554 iv *= 1024; 1555 case 'k': 1556 case 'K': 1557 iv *= 1024; 1558 case '\0': 1559 break; 1560 default: 1561 return (EINVAL); 1562 } 1563 *value = iv; 1564 1565 return (0); 1566 } 1567 1568 char * 1569 vfs_getopts(struct vfsoptlist *opts, const char *name, int *error) 1570 { 1571 struct vfsopt *opt; 1572 1573 *error = 0; 1574 TAILQ_FOREACH(opt, opts, link) { 1575 if (strcmp(name, opt->name) != 0) 1576 continue; 1577 opt->seen = 1; 1578 if (opt->len == 0 || 1579 ((char *)opt->value)[opt->len - 1] != '\0') { 1580 *error = EINVAL; 1581 return (NULL); 1582 } 1583 return (opt->value); 1584 } 1585 *error = ENOENT; 1586 return (NULL); 1587 } 1588 1589 int 1590 vfs_flagopt(struct vfsoptlist *opts, const char *name, uint64_t *w, 1591 uint64_t val) 1592 { 1593 struct vfsopt *opt; 1594 1595 TAILQ_FOREACH(opt, opts, link) { 1596 if (strcmp(name, opt->name) == 0) { 1597 opt->seen = 1; 1598 if (w != NULL) 1599 *w |= val; 1600 return (1); 1601 } 1602 } 1603 if (w != NULL) 1604 *w &= ~val; 1605 return (0); 1606 } 1607 1608 int 1609 vfs_scanopt(struct vfsoptlist *opts, const char *name, const char *fmt, ...) 1610 { 1611 va_list ap; 1612 struct vfsopt *opt; 1613 int ret; 1614 1615 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1616 1617 TAILQ_FOREACH(opt, opts, link) { 1618 if (strcmp(name, opt->name) != 0) 1619 continue; 1620 opt->seen = 1; 1621 if (opt->len == 0 || opt->value == NULL) 1622 return (0); 1623 if (((char *)opt->value)[opt->len - 1] != '\0') 1624 return (0); 1625 va_start(ap, fmt); 1626 ret = vsscanf(opt->value, fmt, ap); 1627 va_end(ap); 1628 return (ret); 1629 } 1630 return (0); 1631 } 1632 1633 int 1634 vfs_setopt(struct vfsoptlist *opts, const char *name, void *value, int len) 1635 { 1636 struct vfsopt *opt; 1637 1638 TAILQ_FOREACH(opt, opts, link) { 1639 if (strcmp(name, opt->name) != 0) 1640 continue; 1641 opt->seen = 1; 1642 if (opt->value == NULL) 1643 opt->len = len; 1644 else { 1645 if (opt->len != len) 1646 return (EINVAL); 1647 bcopy(value, opt->value, len); 1648 } 1649 return (0); 1650 } 1651 return (ENOENT); 1652 } 1653 1654 int 1655 vfs_setopt_part(struct vfsoptlist *opts, const char *name, void *value, int len) 1656 { 1657 struct vfsopt *opt; 1658 1659 TAILQ_FOREACH(opt, opts, link) { 1660 if (strcmp(name, opt->name) != 0) 1661 continue; 1662 opt->seen = 1; 1663 if (opt->value == NULL) 1664 opt->len = len; 1665 else { 1666 if (opt->len < len) 1667 return (EINVAL); 1668 opt->len = len; 1669 bcopy(value, opt->value, len); 1670 } 1671 return (0); 1672 } 1673 return (ENOENT); 1674 } 1675 1676 int 1677 vfs_setopts(struct vfsoptlist *opts, const char *name, const char *value) 1678 { 1679 struct vfsopt *opt; 1680 1681 TAILQ_FOREACH(opt, opts, link) { 1682 if (strcmp(name, opt->name) != 0) 1683 continue; 1684 opt->seen = 1; 1685 if (opt->value == NULL) 1686 opt->len = strlen(value) + 1; 1687 else if (strlcpy(opt->value, value, opt->len) >= opt->len) 1688 return (EINVAL); 1689 return (0); 1690 } 1691 return (ENOENT); 1692 } 1693 1694 /* 1695 * Find and copy a mount option. 1696 * 1697 * The size of the buffer has to be specified 1698 * in len, if it is not the same length as the 1699 * mount option, EINVAL is returned. 1700 * Returns ENOENT if the option is not found. 1701 */ 1702 int 1703 vfs_copyopt(opts, name, dest, len) 1704 struct vfsoptlist *opts; 1705 const char *name; 1706 void *dest; 1707 int len; 1708 { 1709 struct vfsopt *opt; 1710 1711 KASSERT(opts != NULL, ("vfs_copyopt: caller passed 'opts' as NULL")); 1712 1713 TAILQ_FOREACH(opt, opts, link) { 1714 if (strcmp(name, opt->name) == 0) { 1715 opt->seen = 1; 1716 if (len != opt->len) 1717 return (EINVAL); 1718 bcopy(opt->value, dest, opt->len); 1719 return (0); 1720 } 1721 } 1722 return (ENOENT); 1723 } 1724 1725 int 1726 __vfs_statfs(struct mount *mp, struct statfs *sbp) 1727 { 1728 int error; 1729 1730 error = mp->mnt_op->vfs_statfs(mp, &mp->mnt_stat); 1731 if (sbp != &mp->mnt_stat) 1732 *sbp = mp->mnt_stat; 1733 return (error); 1734 } 1735 1736 void 1737 vfs_mountedfrom(struct mount *mp, const char *from) 1738 { 1739 1740 bzero(mp->mnt_stat.f_mntfromname, sizeof mp->mnt_stat.f_mntfromname); 1741 strlcpy(mp->mnt_stat.f_mntfromname, from, 1742 sizeof mp->mnt_stat.f_mntfromname); 1743 } 1744 1745 /* 1746 * --------------------------------------------------------------------- 1747 * This is the api for building mount args and mounting filesystems from 1748 * inside the kernel. 1749 * 1750 * The API works by accumulation of individual args. First error is 1751 * latched. 1752 * 1753 * XXX: should be documented in new manpage kernel_mount(9) 1754 */ 1755 1756 /* A memory allocation which must be freed when we are done */ 1757 struct mntaarg { 1758 SLIST_ENTRY(mntaarg) next; 1759 }; 1760 1761 /* The header for the mount arguments */ 1762 struct mntarg { 1763 struct iovec *v; 1764 int len; 1765 int error; 1766 SLIST_HEAD(, mntaarg) list; 1767 }; 1768 1769 /* 1770 * Add a boolean argument. 1771 * 1772 * flag is the boolean value. 1773 * name must start with "no". 1774 */ 1775 struct mntarg * 1776 mount_argb(struct mntarg *ma, int flag, const char *name) 1777 { 1778 1779 KASSERT(name[0] == 'n' && name[1] == 'o', 1780 ("mount_argb(...,%s): name must start with 'no'", name)); 1781 1782 return (mount_arg(ma, name + (flag ? 2 : 0), NULL, 0)); 1783 } 1784 1785 /* 1786 * Add an argument printf style 1787 */ 1788 struct mntarg * 1789 mount_argf(struct mntarg *ma, const char *name, const char *fmt, ...) 1790 { 1791 va_list ap; 1792 struct mntaarg *maa; 1793 struct sbuf *sb; 1794 int len; 1795 1796 if (ma == NULL) { 1797 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 1798 SLIST_INIT(&ma->list); 1799 } 1800 if (ma->error) 1801 return (ma); 1802 1803 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 1804 M_MOUNT, M_WAITOK); 1805 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 1806 ma->v[ma->len].iov_len = strlen(name) + 1; 1807 ma->len++; 1808 1809 sb = sbuf_new_auto(); 1810 va_start(ap, fmt); 1811 sbuf_vprintf(sb, fmt, ap); 1812 va_end(ap); 1813 sbuf_finish(sb); 1814 len = sbuf_len(sb) + 1; 1815 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 1816 SLIST_INSERT_HEAD(&ma->list, maa, next); 1817 bcopy(sbuf_data(sb), maa + 1, len); 1818 sbuf_delete(sb); 1819 1820 ma->v[ma->len].iov_base = maa + 1; 1821 ma->v[ma->len].iov_len = len; 1822 ma->len++; 1823 1824 return (ma); 1825 } 1826 1827 /* 1828 * Add an argument which is a userland string. 1829 */ 1830 struct mntarg * 1831 mount_argsu(struct mntarg *ma, const char *name, const void *val, int len) 1832 { 1833 struct mntaarg *maa; 1834 char *tbuf; 1835 1836 if (val == NULL) 1837 return (ma); 1838 if (ma == NULL) { 1839 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 1840 SLIST_INIT(&ma->list); 1841 } 1842 if (ma->error) 1843 return (ma); 1844 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 1845 SLIST_INSERT_HEAD(&ma->list, maa, next); 1846 tbuf = (void *)(maa + 1); 1847 ma->error = copyinstr(val, tbuf, len, NULL); 1848 return (mount_arg(ma, name, tbuf, -1)); 1849 } 1850 1851 /* 1852 * Plain argument. 1853 * 1854 * If length is -1, treat value as a C string. 1855 */ 1856 struct mntarg * 1857 mount_arg(struct mntarg *ma, const char *name, const void *val, int len) 1858 { 1859 1860 if (ma == NULL) { 1861 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 1862 SLIST_INIT(&ma->list); 1863 } 1864 if (ma->error) 1865 return (ma); 1866 1867 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 1868 M_MOUNT, M_WAITOK); 1869 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 1870 ma->v[ma->len].iov_len = strlen(name) + 1; 1871 ma->len++; 1872 1873 ma->v[ma->len].iov_base = (void *)(uintptr_t)val; 1874 if (len < 0) 1875 ma->v[ma->len].iov_len = strlen(val) + 1; 1876 else 1877 ma->v[ma->len].iov_len = len; 1878 ma->len++; 1879 return (ma); 1880 } 1881 1882 /* 1883 * Free a mntarg structure 1884 */ 1885 static void 1886 free_mntarg(struct mntarg *ma) 1887 { 1888 struct mntaarg *maa; 1889 1890 while (!SLIST_EMPTY(&ma->list)) { 1891 maa = SLIST_FIRST(&ma->list); 1892 SLIST_REMOVE_HEAD(&ma->list, next); 1893 free(maa, M_MOUNT); 1894 } 1895 free(ma->v, M_MOUNT); 1896 free(ma, M_MOUNT); 1897 } 1898 1899 /* 1900 * Mount a filesystem 1901 */ 1902 int 1903 kernel_mount(struct mntarg *ma, uint64_t flags) 1904 { 1905 struct uio auio; 1906 int error; 1907 1908 KASSERT(ma != NULL, ("kernel_mount NULL ma")); 1909 KASSERT(ma->v != NULL, ("kernel_mount NULL ma->v")); 1910 KASSERT(!(ma->len & 1), ("kernel_mount odd ma->len (%d)", ma->len)); 1911 1912 auio.uio_iov = ma->v; 1913 auio.uio_iovcnt = ma->len; 1914 auio.uio_segflg = UIO_SYSSPACE; 1915 1916 error = ma->error; 1917 if (!error) 1918 error = vfs_donmount(curthread, flags, &auio); 1919 free_mntarg(ma); 1920 return (error); 1921 } 1922 1923 /* 1924 * A printflike function to mount a filesystem. 1925 */ 1926 int 1927 kernel_vmount(int flags, ...) 1928 { 1929 struct mntarg *ma = NULL; 1930 va_list ap; 1931 const char *cp; 1932 const void *vp; 1933 int error; 1934 1935 va_start(ap, flags); 1936 for (;;) { 1937 cp = va_arg(ap, const char *); 1938 if (cp == NULL) 1939 break; 1940 vp = va_arg(ap, const void *); 1941 ma = mount_arg(ma, cp, vp, (vp != NULL ? -1 : 0)); 1942 } 1943 va_end(ap); 1944 1945 error = kernel_mount(ma, flags); 1946 return (error); 1947 } 1948 1949 void 1950 vfs_oexport_conv(const struct oexport_args *oexp, struct export_args *exp) 1951 { 1952 1953 bcopy(oexp, exp, sizeof(*oexp)); 1954 exp->ex_numsecflavors = 0; 1955 } 1956