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 oexport_args oexport; 884 struct export_args export; 885 struct mount *mp; 886 int error, export_error; 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 if (error == 0) { 955 /* Process the export option. */ 956 if (vfs_copyopt(mp->mnt_optnew, "export", &export, 957 sizeof(export)) == 0) { 958 export_error = vfs_export(mp, &export); 959 } else if (vfs_copyopt(mp->mnt_optnew, "export", &oexport, 960 sizeof(oexport)) == 0) { 961 export.ex_flags = oexport.ex_flags; 962 export.ex_root = oexport.ex_root; 963 export.ex_anon = oexport.ex_anon; 964 export.ex_addr = oexport.ex_addr; 965 export.ex_addrlen = oexport.ex_addrlen; 966 export.ex_mask = oexport.ex_mask; 967 export.ex_masklen = oexport.ex_masklen; 968 export.ex_indexfile = oexport.ex_indexfile; 969 export.ex_numsecflavors = 0; 970 export_error = vfs_export(mp, &export); 971 } 972 } 973 974 MNT_ILOCK(mp); 975 if (error == 0) { 976 mp->mnt_flag &= ~(MNT_UPDATE | MNT_RELOAD | MNT_FORCE | 977 MNT_SNAPSHOT); 978 } else { 979 /* 980 * If we fail, restore old mount flags. MNT_QUOTA is special, 981 * because it is not part of MNT_UPDATEMASK, but it could have 982 * changed in the meantime if quotactl(2) was called. 983 * All in all we want current value of MNT_QUOTA, not the old 984 * one. 985 */ 986 mp->mnt_flag = (mp->mnt_flag & MNT_QUOTA) | (flag & ~MNT_QUOTA); 987 } 988 if ((mp->mnt_flag & MNT_ASYNC) != 0 && 989 (mp->mnt_kern_flag & MNTK_NOASYNC) == 0) 990 mp->mnt_kern_flag |= MNTK_ASYNC; 991 else 992 mp->mnt_kern_flag &= ~MNTK_ASYNC; 993 MNT_IUNLOCK(mp); 994 995 if (error != 0) 996 goto end; 997 998 if (mp->mnt_opt != NULL) 999 vfs_freeopts(mp->mnt_opt); 1000 mp->mnt_opt = mp->mnt_optnew; 1001 *optlist = NULL; 1002 (void)VFS_STATFS(mp, &mp->mnt_stat); 1003 /* 1004 * Prevent external consumers of mount options from reading 1005 * mnt_optnew. 1006 */ 1007 mp->mnt_optnew = NULL; 1008 1009 if ((mp->mnt_flag & MNT_RDONLY) == 0) 1010 vfs_allocate_syncvnode(mp); 1011 else 1012 vfs_deallocate_syncvnode(mp); 1013 end: 1014 vfs_unbusy(mp); 1015 VI_LOCK(vp); 1016 vp->v_iflag &= ~VI_MOUNT; 1017 VI_UNLOCK(vp); 1018 vrele(vp); 1019 return (error != 0 ? error : export_error); 1020 } 1021 1022 /* 1023 * vfs_domount(): actually attempt a filesystem mount. 1024 */ 1025 static int 1026 vfs_domount( 1027 struct thread *td, /* Calling thread. */ 1028 const char *fstype, /* Filesystem type. */ 1029 char *fspath, /* Mount path. */ 1030 uint64_t fsflags, /* Flags common to all filesystems. */ 1031 struct vfsoptlist **optlist /* Options local to the filesystem. */ 1032 ) 1033 { 1034 struct vfsconf *vfsp; 1035 struct nameidata nd; 1036 struct vnode *vp; 1037 char *pathbuf; 1038 int error; 1039 1040 /* 1041 * Be ultra-paranoid about making sure the type and fspath 1042 * variables will fit in our mp buffers, including the 1043 * terminating NUL. 1044 */ 1045 if (strlen(fstype) >= MFSNAMELEN || strlen(fspath) >= MNAMELEN) 1046 return (ENAMETOOLONG); 1047 1048 if (jailed(td->td_ucred) || usermount == 0) { 1049 if ((error = priv_check(td, PRIV_VFS_MOUNT)) != 0) 1050 return (error); 1051 } 1052 1053 /* 1054 * Do not allow NFS export or MNT_SUIDDIR by unprivileged users. 1055 */ 1056 if (fsflags & MNT_EXPORTED) { 1057 error = priv_check(td, PRIV_VFS_MOUNT_EXPORTED); 1058 if (error) 1059 return (error); 1060 } 1061 if (fsflags & MNT_SUIDDIR) { 1062 error = priv_check(td, PRIV_VFS_MOUNT_SUIDDIR); 1063 if (error) 1064 return (error); 1065 } 1066 /* 1067 * Silently enforce MNT_NOSUID and MNT_USER for unprivileged users. 1068 */ 1069 if ((fsflags & (MNT_NOSUID | MNT_USER)) != (MNT_NOSUID | MNT_USER)) { 1070 if (priv_check(td, PRIV_VFS_MOUNT_NONUSER) != 0) 1071 fsflags |= MNT_NOSUID | MNT_USER; 1072 } 1073 1074 /* Load KLDs before we lock the covered vnode to avoid reversals. */ 1075 vfsp = NULL; 1076 if ((fsflags & MNT_UPDATE) == 0) { 1077 /* Don't try to load KLDs if we're mounting the root. */ 1078 if (fsflags & MNT_ROOTFS) 1079 vfsp = vfs_byname(fstype); 1080 else 1081 vfsp = vfs_byname_kld(fstype, td, &error); 1082 if (vfsp == NULL) 1083 return (ENODEV); 1084 if (jailed(td->td_ucred) && !(vfsp->vfc_flags & VFCF_JAIL)) 1085 return (EPERM); 1086 } 1087 1088 /* 1089 * Get vnode to be covered or mount point's vnode in case of MNT_UPDATE. 1090 */ 1091 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, 1092 UIO_SYSSPACE, fspath, td); 1093 error = namei(&nd); 1094 if (error != 0) 1095 return (error); 1096 NDFREE(&nd, NDF_ONLY_PNBUF); 1097 vp = nd.ni_vp; 1098 if ((fsflags & MNT_UPDATE) == 0) { 1099 pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK); 1100 strcpy(pathbuf, fspath); 1101 error = vn_path_to_global_path(td, vp, pathbuf, MNAMELEN); 1102 /* debug.disablefullpath == 1 results in ENODEV */ 1103 if (error == 0 || error == ENODEV) { 1104 error = vfs_domount_first(td, vfsp, pathbuf, vp, 1105 fsflags, optlist); 1106 } 1107 free(pathbuf, M_TEMP); 1108 } else 1109 error = vfs_domount_update(td, vp, fsflags, optlist); 1110 1111 ASSERT_VI_UNLOCKED(vp, __func__); 1112 ASSERT_VOP_UNLOCKED(vp, __func__); 1113 1114 return (error); 1115 } 1116 1117 /* 1118 * Unmount a filesystem. 1119 * 1120 * Note: unmount takes a path to the vnode mounted on as argument, not 1121 * special file (as before). 1122 */ 1123 #ifndef _SYS_SYSPROTO_H_ 1124 struct unmount_args { 1125 char *path; 1126 int flags; 1127 }; 1128 #endif 1129 /* ARGSUSED */ 1130 int 1131 sys_unmount(td, uap) 1132 struct thread *td; 1133 register struct unmount_args /* { 1134 char *path; 1135 int flags; 1136 } */ *uap; 1137 { 1138 struct nameidata nd; 1139 struct mount *mp; 1140 char *pathbuf; 1141 int error, id0, id1; 1142 1143 AUDIT_ARG_VALUE(uap->flags); 1144 if (jailed(td->td_ucred) || usermount == 0) { 1145 error = priv_check(td, PRIV_VFS_UNMOUNT); 1146 if (error) 1147 return (error); 1148 } 1149 1150 pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK); 1151 error = copyinstr(uap->path, pathbuf, MNAMELEN, NULL); 1152 if (error) { 1153 free(pathbuf, M_TEMP); 1154 return (error); 1155 } 1156 if (uap->flags & MNT_BYFSID) { 1157 AUDIT_ARG_TEXT(pathbuf); 1158 /* Decode the filesystem ID. */ 1159 if (sscanf(pathbuf, "FSID:%d:%d", &id0, &id1) != 2) { 1160 free(pathbuf, M_TEMP); 1161 return (EINVAL); 1162 } 1163 1164 mtx_lock(&mountlist_mtx); 1165 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1166 if (mp->mnt_stat.f_fsid.val[0] == id0 && 1167 mp->mnt_stat.f_fsid.val[1] == id1) 1168 break; 1169 } 1170 mtx_unlock(&mountlist_mtx); 1171 } else { 1172 /* 1173 * Try to find global path for path argument. 1174 */ 1175 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, 1176 UIO_SYSSPACE, pathbuf, td); 1177 if (namei(&nd) == 0) { 1178 NDFREE(&nd, NDF_ONLY_PNBUF); 1179 error = vn_path_to_global_path(td, nd.ni_vp, pathbuf, 1180 MNAMELEN); 1181 if (error == 0 || error == ENODEV) 1182 vput(nd.ni_vp); 1183 } 1184 mtx_lock(&mountlist_mtx); 1185 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1186 if (strcmp(mp->mnt_stat.f_mntonname, pathbuf) == 0) 1187 break; 1188 } 1189 mtx_unlock(&mountlist_mtx); 1190 } 1191 free(pathbuf, M_TEMP); 1192 if (mp == NULL) { 1193 /* 1194 * Previously we returned ENOENT for a nonexistent path and 1195 * EINVAL for a non-mountpoint. We cannot tell these apart 1196 * now, so in the !MNT_BYFSID case return the more likely 1197 * EINVAL for compatibility. 1198 */ 1199 return ((uap->flags & MNT_BYFSID) ? ENOENT : EINVAL); 1200 } 1201 1202 /* 1203 * Don't allow unmounting the root filesystem. 1204 */ 1205 if (mp->mnt_flag & MNT_ROOTFS) 1206 return (EINVAL); 1207 error = dounmount(mp, uap->flags, td); 1208 return (error); 1209 } 1210 1211 /* 1212 * Do the actual filesystem unmount. 1213 */ 1214 int 1215 dounmount(mp, flags, td) 1216 struct mount *mp; 1217 int flags; 1218 struct thread *td; 1219 { 1220 struct vnode *coveredvp, *fsrootvp; 1221 int error; 1222 uint64_t async_flag; 1223 int mnt_gen_r; 1224 1225 if ((coveredvp = mp->mnt_vnodecovered) != NULL) { 1226 mnt_gen_r = mp->mnt_gen; 1227 VI_LOCK(coveredvp); 1228 vholdl(coveredvp); 1229 vn_lock(coveredvp, LK_EXCLUSIVE | LK_INTERLOCK | LK_RETRY); 1230 vdrop(coveredvp); 1231 /* 1232 * Check for mp being unmounted while waiting for the 1233 * covered vnode lock. 1234 */ 1235 if (coveredvp->v_mountedhere != mp || 1236 coveredvp->v_mountedhere->mnt_gen != mnt_gen_r) { 1237 VOP_UNLOCK(coveredvp, 0); 1238 return (EBUSY); 1239 } 1240 } 1241 /* 1242 * Only privileged root, or (if MNT_USER is set) the user that did the 1243 * original mount is permitted to unmount this filesystem. 1244 */ 1245 error = vfs_suser(mp, td); 1246 if (error) { 1247 if (coveredvp) 1248 VOP_UNLOCK(coveredvp, 0); 1249 return (error); 1250 } 1251 1252 vn_start_write(NULL, &mp, V_WAIT); 1253 MNT_ILOCK(mp); 1254 if ((mp->mnt_kern_flag & MNTK_UNMOUNT) != 0 || 1255 !TAILQ_EMPTY(&mp->mnt_uppers)) { 1256 MNT_IUNLOCK(mp); 1257 if (coveredvp) 1258 VOP_UNLOCK(coveredvp, 0); 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 vfs_msync(mp, MNT_WAIT); 1292 MNT_ILOCK(mp); 1293 async_flag = mp->mnt_flag & MNT_ASYNC; 1294 mp->mnt_flag &= ~MNT_ASYNC; 1295 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1296 MNT_IUNLOCK(mp); 1297 cache_purgevfs(mp); /* remove cache entries for this file sys */ 1298 vfs_deallocate_syncvnode(mp); 1299 /* 1300 * For forced unmounts, move process cdir/rdir refs on the fs root 1301 * vnode to the covered vnode. For non-forced unmounts we want 1302 * such references to cause an EBUSY error. 1303 */ 1304 if ((flags & MNT_FORCE) && 1305 VFS_ROOT(mp, LK_EXCLUSIVE, &fsrootvp) == 0) { 1306 if (mp->mnt_vnodecovered != NULL) 1307 mountcheckdirs(fsrootvp, mp->mnt_vnodecovered); 1308 if (fsrootvp == rootvnode) { 1309 vrele(rootvnode); 1310 rootvnode = NULL; 1311 } 1312 vput(fsrootvp); 1313 } 1314 if ((mp->mnt_flag & MNT_RDONLY) != 0 || (flags & MNT_FORCE) != 0 || 1315 (error = VFS_SYNC(mp, MNT_WAIT)) == 0) 1316 error = VFS_UNMOUNT(mp, flags); 1317 vn_finished_write(mp); 1318 /* 1319 * If we failed to flush the dirty blocks for this mount point, 1320 * undo all the cdir/rdir and rootvnode changes we made above. 1321 * Unless we failed to do so because the device is reporting that 1322 * it doesn't exist anymore. 1323 */ 1324 if (error && error != ENXIO) { 1325 if ((flags & MNT_FORCE) && 1326 VFS_ROOT(mp, LK_EXCLUSIVE, &fsrootvp) == 0) { 1327 if (mp->mnt_vnodecovered != NULL) 1328 mountcheckdirs(mp->mnt_vnodecovered, fsrootvp); 1329 if (rootvnode == NULL) { 1330 rootvnode = fsrootvp; 1331 vref(rootvnode); 1332 } 1333 vput(fsrootvp); 1334 } 1335 MNT_ILOCK(mp); 1336 mp->mnt_kern_flag &= ~MNTK_NOINSMNTQ; 1337 if ((mp->mnt_flag & MNT_RDONLY) == 0) { 1338 MNT_IUNLOCK(mp); 1339 vfs_allocate_syncvnode(mp); 1340 MNT_ILOCK(mp); 1341 } 1342 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 1343 mp->mnt_flag |= async_flag; 1344 if ((mp->mnt_flag & MNT_ASYNC) != 0 && 1345 (mp->mnt_kern_flag & MNTK_NOASYNC) == 0) 1346 mp->mnt_kern_flag |= MNTK_ASYNC; 1347 if (mp->mnt_kern_flag & MNTK_MWAIT) { 1348 mp->mnt_kern_flag &= ~MNTK_MWAIT; 1349 wakeup(mp); 1350 } 1351 MNT_IUNLOCK(mp); 1352 if (coveredvp) 1353 VOP_UNLOCK(coveredvp, 0); 1354 return (error); 1355 } 1356 mtx_lock(&mountlist_mtx); 1357 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1358 mtx_unlock(&mountlist_mtx); 1359 EVENTHANDLER_INVOKE(vfs_unmounted, mp, td); 1360 if (coveredvp != NULL) { 1361 coveredvp->v_mountedhere = NULL; 1362 vput(coveredvp); 1363 } 1364 vfs_event_signal(NULL, VQ_UNMOUNT, 0); 1365 vfs_mount_destroy(mp); 1366 return (0); 1367 } 1368 1369 /* 1370 * Report errors during filesystem mounting. 1371 */ 1372 void 1373 vfs_mount_error(struct mount *mp, const char *fmt, ...) 1374 { 1375 struct vfsoptlist *moptlist = mp->mnt_optnew; 1376 va_list ap; 1377 int error, len; 1378 char *errmsg; 1379 1380 error = vfs_getopt(moptlist, "errmsg", (void **)&errmsg, &len); 1381 if (error || errmsg == NULL || len <= 0) 1382 return; 1383 1384 va_start(ap, fmt); 1385 vsnprintf(errmsg, (size_t)len, fmt, ap); 1386 va_end(ap); 1387 } 1388 1389 void 1390 vfs_opterror(struct vfsoptlist *opts, const char *fmt, ...) 1391 { 1392 va_list ap; 1393 int error, len; 1394 char *errmsg; 1395 1396 error = vfs_getopt(opts, "errmsg", (void **)&errmsg, &len); 1397 if (error || errmsg == NULL || len <= 0) 1398 return; 1399 1400 va_start(ap, fmt); 1401 vsnprintf(errmsg, (size_t)len, fmt, ap); 1402 va_end(ap); 1403 } 1404 1405 /* 1406 * --------------------------------------------------------------------- 1407 * Functions for querying mount options/arguments from filesystems. 1408 */ 1409 1410 /* 1411 * Check that no unknown options are given 1412 */ 1413 int 1414 vfs_filteropt(struct vfsoptlist *opts, const char **legal) 1415 { 1416 struct vfsopt *opt; 1417 char errmsg[255]; 1418 const char **t, *p, *q; 1419 int ret = 0; 1420 1421 TAILQ_FOREACH(opt, opts, link) { 1422 p = opt->name; 1423 q = NULL; 1424 if (p[0] == 'n' && p[1] == 'o') 1425 q = p + 2; 1426 for(t = global_opts; *t != NULL; t++) { 1427 if (strcmp(*t, p) == 0) 1428 break; 1429 if (q != NULL) { 1430 if (strcmp(*t, q) == 0) 1431 break; 1432 } 1433 } 1434 if (*t != NULL) 1435 continue; 1436 for(t = legal; *t != NULL; t++) { 1437 if (strcmp(*t, p) == 0) 1438 break; 1439 if (q != NULL) { 1440 if (strcmp(*t, q) == 0) 1441 break; 1442 } 1443 } 1444 if (*t != NULL) 1445 continue; 1446 snprintf(errmsg, sizeof(errmsg), 1447 "mount option <%s> is unknown", p); 1448 ret = EINVAL; 1449 } 1450 if (ret != 0) { 1451 TAILQ_FOREACH(opt, opts, link) { 1452 if (strcmp(opt->name, "errmsg") == 0) { 1453 strncpy((char *)opt->value, errmsg, opt->len); 1454 break; 1455 } 1456 } 1457 if (opt == NULL) 1458 printf("%s\n", errmsg); 1459 } 1460 return (ret); 1461 } 1462 1463 /* 1464 * Get a mount option by its name. 1465 * 1466 * Return 0 if the option was found, ENOENT otherwise. 1467 * If len is non-NULL it will be filled with the length 1468 * of the option. If buf is non-NULL, it will be filled 1469 * with the address of the option. 1470 */ 1471 int 1472 vfs_getopt(opts, name, buf, len) 1473 struct vfsoptlist *opts; 1474 const char *name; 1475 void **buf; 1476 int *len; 1477 { 1478 struct vfsopt *opt; 1479 1480 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1481 1482 TAILQ_FOREACH(opt, opts, link) { 1483 if (strcmp(name, opt->name) == 0) { 1484 opt->seen = 1; 1485 if (len != NULL) 1486 *len = opt->len; 1487 if (buf != NULL) 1488 *buf = opt->value; 1489 return (0); 1490 } 1491 } 1492 return (ENOENT); 1493 } 1494 1495 int 1496 vfs_getopt_pos(struct vfsoptlist *opts, const char *name) 1497 { 1498 struct vfsopt *opt; 1499 1500 if (opts == NULL) 1501 return (-1); 1502 1503 TAILQ_FOREACH(opt, opts, link) { 1504 if (strcmp(name, opt->name) == 0) { 1505 opt->seen = 1; 1506 return (opt->pos); 1507 } 1508 } 1509 return (-1); 1510 } 1511 1512 int 1513 vfs_getopt_size(struct vfsoptlist *opts, const char *name, off_t *value) 1514 { 1515 char *opt_value, *vtp; 1516 quad_t iv; 1517 int error, opt_len; 1518 1519 error = vfs_getopt(opts, name, (void **)&opt_value, &opt_len); 1520 if (error != 0) 1521 return (error); 1522 if (opt_len == 0 || opt_value == NULL) 1523 return (EINVAL); 1524 if (opt_value[0] == '\0' || opt_value[opt_len - 1] != '\0') 1525 return (EINVAL); 1526 iv = strtoq(opt_value, &vtp, 0); 1527 if (vtp == opt_value || (vtp[0] != '\0' && vtp[1] != '\0')) 1528 return (EINVAL); 1529 if (iv < 0) 1530 return (EINVAL); 1531 switch (vtp[0]) { 1532 case 't': 1533 case 'T': 1534 iv *= 1024; 1535 case 'g': 1536 case 'G': 1537 iv *= 1024; 1538 case 'm': 1539 case 'M': 1540 iv *= 1024; 1541 case 'k': 1542 case 'K': 1543 iv *= 1024; 1544 case '\0': 1545 break; 1546 default: 1547 return (EINVAL); 1548 } 1549 *value = iv; 1550 1551 return (0); 1552 } 1553 1554 char * 1555 vfs_getopts(struct vfsoptlist *opts, const char *name, int *error) 1556 { 1557 struct vfsopt *opt; 1558 1559 *error = 0; 1560 TAILQ_FOREACH(opt, opts, link) { 1561 if (strcmp(name, opt->name) != 0) 1562 continue; 1563 opt->seen = 1; 1564 if (opt->len == 0 || 1565 ((char *)opt->value)[opt->len - 1] != '\0') { 1566 *error = EINVAL; 1567 return (NULL); 1568 } 1569 return (opt->value); 1570 } 1571 *error = ENOENT; 1572 return (NULL); 1573 } 1574 1575 int 1576 vfs_flagopt(struct vfsoptlist *opts, const char *name, uint64_t *w, 1577 uint64_t val) 1578 { 1579 struct vfsopt *opt; 1580 1581 TAILQ_FOREACH(opt, opts, link) { 1582 if (strcmp(name, opt->name) == 0) { 1583 opt->seen = 1; 1584 if (w != NULL) 1585 *w |= val; 1586 return (1); 1587 } 1588 } 1589 if (w != NULL) 1590 *w &= ~val; 1591 return (0); 1592 } 1593 1594 int 1595 vfs_scanopt(struct vfsoptlist *opts, const char *name, const char *fmt, ...) 1596 { 1597 va_list ap; 1598 struct vfsopt *opt; 1599 int ret; 1600 1601 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1602 1603 TAILQ_FOREACH(opt, opts, link) { 1604 if (strcmp(name, opt->name) != 0) 1605 continue; 1606 opt->seen = 1; 1607 if (opt->len == 0 || opt->value == NULL) 1608 return (0); 1609 if (((char *)opt->value)[opt->len - 1] != '\0') 1610 return (0); 1611 va_start(ap, fmt); 1612 ret = vsscanf(opt->value, fmt, ap); 1613 va_end(ap); 1614 return (ret); 1615 } 1616 return (0); 1617 } 1618 1619 int 1620 vfs_setopt(struct vfsoptlist *opts, const char *name, void *value, int len) 1621 { 1622 struct vfsopt *opt; 1623 1624 TAILQ_FOREACH(opt, opts, link) { 1625 if (strcmp(name, opt->name) != 0) 1626 continue; 1627 opt->seen = 1; 1628 if (opt->value == NULL) 1629 opt->len = len; 1630 else { 1631 if (opt->len != len) 1632 return (EINVAL); 1633 bcopy(value, opt->value, len); 1634 } 1635 return (0); 1636 } 1637 return (ENOENT); 1638 } 1639 1640 int 1641 vfs_setopt_part(struct vfsoptlist *opts, const char *name, void *value, int len) 1642 { 1643 struct vfsopt *opt; 1644 1645 TAILQ_FOREACH(opt, opts, link) { 1646 if (strcmp(name, opt->name) != 0) 1647 continue; 1648 opt->seen = 1; 1649 if (opt->value == NULL) 1650 opt->len = len; 1651 else { 1652 if (opt->len < len) 1653 return (EINVAL); 1654 opt->len = len; 1655 bcopy(value, opt->value, len); 1656 } 1657 return (0); 1658 } 1659 return (ENOENT); 1660 } 1661 1662 int 1663 vfs_setopts(struct vfsoptlist *opts, const char *name, const char *value) 1664 { 1665 struct vfsopt *opt; 1666 1667 TAILQ_FOREACH(opt, opts, link) { 1668 if (strcmp(name, opt->name) != 0) 1669 continue; 1670 opt->seen = 1; 1671 if (opt->value == NULL) 1672 opt->len = strlen(value) + 1; 1673 else if (strlcpy(opt->value, value, opt->len) >= opt->len) 1674 return (EINVAL); 1675 return (0); 1676 } 1677 return (ENOENT); 1678 } 1679 1680 /* 1681 * Find and copy a mount option. 1682 * 1683 * The size of the buffer has to be specified 1684 * in len, if it is not the same length as the 1685 * mount option, EINVAL is returned. 1686 * Returns ENOENT if the option is not found. 1687 */ 1688 int 1689 vfs_copyopt(opts, name, dest, len) 1690 struct vfsoptlist *opts; 1691 const char *name; 1692 void *dest; 1693 int len; 1694 { 1695 struct vfsopt *opt; 1696 1697 KASSERT(opts != NULL, ("vfs_copyopt: caller passed 'opts' as NULL")); 1698 1699 TAILQ_FOREACH(opt, opts, link) { 1700 if (strcmp(name, opt->name) == 0) { 1701 opt->seen = 1; 1702 if (len != opt->len) 1703 return (EINVAL); 1704 bcopy(opt->value, dest, opt->len); 1705 return (0); 1706 } 1707 } 1708 return (ENOENT); 1709 } 1710 1711 int 1712 __vfs_statfs(struct mount *mp, struct statfs *sbp) 1713 { 1714 int error; 1715 1716 error = mp->mnt_op->vfs_statfs(mp, &mp->mnt_stat); 1717 if (sbp != &mp->mnt_stat) 1718 *sbp = mp->mnt_stat; 1719 return (error); 1720 } 1721 1722 void 1723 vfs_mountedfrom(struct mount *mp, const char *from) 1724 { 1725 1726 bzero(mp->mnt_stat.f_mntfromname, sizeof mp->mnt_stat.f_mntfromname); 1727 strlcpy(mp->mnt_stat.f_mntfromname, from, 1728 sizeof mp->mnt_stat.f_mntfromname); 1729 } 1730 1731 /* 1732 * --------------------------------------------------------------------- 1733 * This is the api for building mount args and mounting filesystems from 1734 * inside the kernel. 1735 * 1736 * The API works by accumulation of individual args. First error is 1737 * latched. 1738 * 1739 * XXX: should be documented in new manpage kernel_mount(9) 1740 */ 1741 1742 /* A memory allocation which must be freed when we are done */ 1743 struct mntaarg { 1744 SLIST_ENTRY(mntaarg) next; 1745 }; 1746 1747 /* The header for the mount arguments */ 1748 struct mntarg { 1749 struct iovec *v; 1750 int len; 1751 int error; 1752 SLIST_HEAD(, mntaarg) list; 1753 }; 1754 1755 /* 1756 * Add a boolean argument. 1757 * 1758 * flag is the boolean value. 1759 * name must start with "no". 1760 */ 1761 struct mntarg * 1762 mount_argb(struct mntarg *ma, int flag, const char *name) 1763 { 1764 1765 KASSERT(name[0] == 'n' && name[1] == 'o', 1766 ("mount_argb(...,%s): name must start with 'no'", name)); 1767 1768 return (mount_arg(ma, name + (flag ? 2 : 0), NULL, 0)); 1769 } 1770 1771 /* 1772 * Add an argument printf style 1773 */ 1774 struct mntarg * 1775 mount_argf(struct mntarg *ma, const char *name, const char *fmt, ...) 1776 { 1777 va_list ap; 1778 struct mntaarg *maa; 1779 struct sbuf *sb; 1780 int len; 1781 1782 if (ma == NULL) { 1783 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 1784 SLIST_INIT(&ma->list); 1785 } 1786 if (ma->error) 1787 return (ma); 1788 1789 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 1790 M_MOUNT, M_WAITOK); 1791 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 1792 ma->v[ma->len].iov_len = strlen(name) + 1; 1793 ma->len++; 1794 1795 sb = sbuf_new_auto(); 1796 va_start(ap, fmt); 1797 sbuf_vprintf(sb, fmt, ap); 1798 va_end(ap); 1799 sbuf_finish(sb); 1800 len = sbuf_len(sb) + 1; 1801 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 1802 SLIST_INSERT_HEAD(&ma->list, maa, next); 1803 bcopy(sbuf_data(sb), maa + 1, len); 1804 sbuf_delete(sb); 1805 1806 ma->v[ma->len].iov_base = maa + 1; 1807 ma->v[ma->len].iov_len = len; 1808 ma->len++; 1809 1810 return (ma); 1811 } 1812 1813 /* 1814 * Add an argument which is a userland string. 1815 */ 1816 struct mntarg * 1817 mount_argsu(struct mntarg *ma, const char *name, const void *val, int len) 1818 { 1819 struct mntaarg *maa; 1820 char *tbuf; 1821 1822 if (val == NULL) 1823 return (ma); 1824 if (ma == NULL) { 1825 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 1826 SLIST_INIT(&ma->list); 1827 } 1828 if (ma->error) 1829 return (ma); 1830 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 1831 SLIST_INSERT_HEAD(&ma->list, maa, next); 1832 tbuf = (void *)(maa + 1); 1833 ma->error = copyinstr(val, tbuf, len, NULL); 1834 return (mount_arg(ma, name, tbuf, -1)); 1835 } 1836 1837 /* 1838 * Plain argument. 1839 * 1840 * If length is -1, treat value as a C string. 1841 */ 1842 struct mntarg * 1843 mount_arg(struct mntarg *ma, const char *name, const void *val, int len) 1844 { 1845 1846 if (ma == NULL) { 1847 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 1848 SLIST_INIT(&ma->list); 1849 } 1850 if (ma->error) 1851 return (ma); 1852 1853 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 1854 M_MOUNT, M_WAITOK); 1855 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 1856 ma->v[ma->len].iov_len = strlen(name) + 1; 1857 ma->len++; 1858 1859 ma->v[ma->len].iov_base = (void *)(uintptr_t)val; 1860 if (len < 0) 1861 ma->v[ma->len].iov_len = strlen(val) + 1; 1862 else 1863 ma->v[ma->len].iov_len = len; 1864 ma->len++; 1865 return (ma); 1866 } 1867 1868 /* 1869 * Free a mntarg structure 1870 */ 1871 static void 1872 free_mntarg(struct mntarg *ma) 1873 { 1874 struct mntaarg *maa; 1875 1876 while (!SLIST_EMPTY(&ma->list)) { 1877 maa = SLIST_FIRST(&ma->list); 1878 SLIST_REMOVE_HEAD(&ma->list, next); 1879 free(maa, M_MOUNT); 1880 } 1881 free(ma->v, M_MOUNT); 1882 free(ma, M_MOUNT); 1883 } 1884 1885 /* 1886 * Mount a filesystem 1887 */ 1888 int 1889 kernel_mount(struct mntarg *ma, uint64_t flags) 1890 { 1891 struct uio auio; 1892 int error; 1893 1894 KASSERT(ma != NULL, ("kernel_mount NULL ma")); 1895 KASSERT(ma->v != NULL, ("kernel_mount NULL ma->v")); 1896 KASSERT(!(ma->len & 1), ("kernel_mount odd ma->len (%d)", ma->len)); 1897 1898 auio.uio_iov = ma->v; 1899 auio.uio_iovcnt = ma->len; 1900 auio.uio_segflg = UIO_SYSSPACE; 1901 1902 error = ma->error; 1903 if (!error) 1904 error = vfs_donmount(curthread, flags, &auio); 1905 free_mntarg(ma); 1906 return (error); 1907 } 1908 1909 /* 1910 * A printflike function to mount a filesystem. 1911 */ 1912 int 1913 kernel_vmount(int flags, ...) 1914 { 1915 struct mntarg *ma = NULL; 1916 va_list ap; 1917 const char *cp; 1918 const void *vp; 1919 int error; 1920 1921 va_start(ap, flags); 1922 for (;;) { 1923 cp = va_arg(ap, const char *); 1924 if (cp == NULL) 1925 break; 1926 vp = va_arg(ap, const void *); 1927 ma = mount_arg(ma, cp, vp, (vp != NULL ? -1 : 0)); 1928 } 1929 va_end(ap); 1930 1931 error = kernel_mount(ma, flags); 1932 return (error); 1933 } 1934 1935 void 1936 vfs_oexport_conv(const struct oexport_args *oexp, struct export_args *exp) 1937 { 1938 1939 bcopy(oexp, exp, sizeof(*oexp)); 1940 exp->ex_numsecflavors = 0; 1941 } 1942