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 mp->mnt_op = vfsp->vfc_vfsops; 467 mp->mnt_vfc = vfsp; 468 vfsp->vfc_refcount++; /* XXX Unlocked */ 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 mp->mnt_vfc->vfc_refcount--; 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 } 653 654 /* 655 * Be ultra-paranoid about making sure the type and fspath 656 * variables will fit in our mp buffers, including the 657 * terminating NUL. 658 */ 659 if (fstypelen >= MFSNAMELEN - 1 || fspathlen >= MNAMELEN - 1) { 660 error = ENAMETOOLONG; 661 goto bail; 662 } 663 664 error = vfs_domount(td, fstype, fspath, fsflags, &optlist); 665 bail: 666 /* copyout the errmsg */ 667 if (errmsg_pos != -1 && ((2 * errmsg_pos + 1) < fsoptions->uio_iovcnt) 668 && errmsg_len > 0 && errmsg != NULL) { 669 if (fsoptions->uio_segflg == UIO_SYSSPACE) { 670 bcopy(errmsg, 671 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_base, 672 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_len); 673 } else { 674 copyout(errmsg, 675 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_base, 676 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_len); 677 } 678 } 679 680 if (optlist != NULL) 681 vfs_freeopts(optlist); 682 return (error); 683 } 684 685 /* 686 * Old mount API. 687 */ 688 #ifndef _SYS_SYSPROTO_H_ 689 struct mount_args { 690 char *type; 691 char *path; 692 int flags; 693 caddr_t data; 694 }; 695 #endif 696 /* ARGSUSED */ 697 int 698 sys_mount(td, uap) 699 struct thread *td; 700 struct mount_args /* { 701 char *type; 702 char *path; 703 int flags; 704 caddr_t data; 705 } */ *uap; 706 { 707 char *fstype; 708 struct vfsconf *vfsp = NULL; 709 struct mntarg *ma = NULL; 710 uint64_t flags; 711 int error; 712 713 /* 714 * Mount flags are now 64-bits. On 32-bit architectures only 715 * 32-bits are passed in, but from here on everything handles 716 * 64-bit flags correctly. 717 */ 718 flags = uap->flags; 719 720 AUDIT_ARG_FFLAGS(flags); 721 722 /* 723 * Filter out MNT_ROOTFS. We do not want clients of mount() in 724 * userspace to set this flag, but we must filter it out if we want 725 * MNT_UPDATE on the root file system to work. 726 * MNT_ROOTFS should only be set by the kernel when mounting its 727 * root file system. 728 */ 729 flags &= ~MNT_ROOTFS; 730 731 fstype = malloc(MFSNAMELEN, M_TEMP, M_WAITOK); 732 error = copyinstr(uap->type, fstype, MFSNAMELEN, NULL); 733 if (error) { 734 free(fstype, M_TEMP); 735 return (error); 736 } 737 738 AUDIT_ARG_TEXT(fstype); 739 mtx_lock(&Giant); 740 vfsp = vfs_byname_kld(fstype, td, &error); 741 free(fstype, M_TEMP); 742 if (vfsp == NULL) { 743 mtx_unlock(&Giant); 744 return (ENOENT); 745 } 746 if (vfsp->vfc_vfsops->vfs_cmount == NULL) { 747 mtx_unlock(&Giant); 748 return (EOPNOTSUPP); 749 } 750 751 ma = mount_argsu(ma, "fstype", uap->type, MNAMELEN); 752 ma = mount_argsu(ma, "fspath", uap->path, MNAMELEN); 753 ma = mount_argb(ma, flags & MNT_RDONLY, "noro"); 754 ma = mount_argb(ma, !(flags & MNT_NOSUID), "nosuid"); 755 ma = mount_argb(ma, !(flags & MNT_NOEXEC), "noexec"); 756 757 error = vfsp->vfc_vfsops->vfs_cmount(ma, uap->data, flags); 758 mtx_unlock(&Giant); 759 return (error); 760 } 761 762 /* 763 * vfs_domount_first(): first file system mount (not update) 764 */ 765 static int 766 vfs_domount_first( 767 struct thread *td, /* Calling thread. */ 768 struct vfsconf *vfsp, /* File system type. */ 769 char *fspath, /* Mount path. */ 770 struct vnode *vp, /* Vnode to be covered. */ 771 uint64_t fsflags, /* Flags common to all filesystems. */ 772 struct vfsoptlist **optlist /* Options local to the filesystem. */ 773 ) 774 { 775 struct vattr va; 776 struct mount *mp; 777 struct vnode *newdp; 778 int error; 779 780 mtx_assert(&Giant, MA_OWNED); 781 ASSERT_VOP_ELOCKED(vp, __func__); 782 KASSERT((fsflags & MNT_UPDATE) == 0, ("MNT_UPDATE shouldn't be here")); 783 784 /* 785 * If the user is not root, ensure that they own the directory 786 * onto which we are attempting to mount. 787 */ 788 error = VOP_GETATTR(vp, &va, td->td_ucred); 789 if (error == 0 && va.va_uid != td->td_ucred->cr_uid) 790 error = priv_check_cred(td->td_ucred, PRIV_VFS_ADMIN, 0); 791 if (error == 0) 792 error = vinvalbuf(vp, V_SAVE, 0, 0); 793 if (error == 0 && vp->v_type != VDIR) 794 error = ENOTDIR; 795 if (error == 0) { 796 VI_LOCK(vp); 797 if ((vp->v_iflag & VI_MOUNT) == 0 && vp->v_mountedhere == NULL) 798 vp->v_iflag |= VI_MOUNT; 799 else 800 error = EBUSY; 801 VI_UNLOCK(vp); 802 } 803 if (error != 0) { 804 vput(vp); 805 return (error); 806 } 807 VOP_UNLOCK(vp, 0); 808 809 /* Allocate and initialize the filesystem. */ 810 mp = vfs_mount_alloc(vp, vfsp, fspath, td->td_ucred); 811 /* XXXMAC: pass to vfs_mount_alloc? */ 812 mp->mnt_optnew = *optlist; 813 /* Set the mount level flags. */ 814 mp->mnt_flag = (fsflags & (MNT_UPDATEMASK | MNT_ROOTFS | MNT_RDONLY)); 815 816 /* 817 * Mount the filesystem. 818 * XXX The final recipients of VFS_MOUNT just overwrite the ndp they 819 * get. No freeing of cn_pnbuf. 820 */ 821 error = VFS_MOUNT(mp); 822 if (error != 0) { 823 vfs_unbusy(mp); 824 vfs_mount_destroy(mp); 825 VI_LOCK(vp); 826 vp->v_iflag &= ~VI_MOUNT; 827 VI_UNLOCK(vp); 828 vrele(vp); 829 return (error); 830 } 831 832 if (mp->mnt_opt != NULL) 833 vfs_freeopts(mp->mnt_opt); 834 mp->mnt_opt = mp->mnt_optnew; 835 *optlist = NULL; 836 (void)VFS_STATFS(mp, &mp->mnt_stat); 837 838 /* 839 * Prevent external consumers of mount options from reading mnt_optnew. 840 */ 841 mp->mnt_optnew = NULL; 842 843 MNT_ILOCK(mp); 844 if ((mp->mnt_flag & MNT_ASYNC) != 0 && 845 (mp->mnt_kern_flag & MNTK_NOASYNC) == 0) 846 mp->mnt_kern_flag |= MNTK_ASYNC; 847 else 848 mp->mnt_kern_flag &= ~MNTK_ASYNC; 849 MNT_IUNLOCK(mp); 850 851 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 852 cache_purge(vp); 853 VI_LOCK(vp); 854 vp->v_iflag &= ~VI_MOUNT; 855 VI_UNLOCK(vp); 856 vp->v_mountedhere = mp; 857 /* Place the new filesystem at the end of the mount list. */ 858 mtx_lock(&mountlist_mtx); 859 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 860 mtx_unlock(&mountlist_mtx); 861 vfs_event_signal(NULL, VQ_MOUNT, 0); 862 if (VFS_ROOT(mp, LK_EXCLUSIVE, &newdp)) 863 panic("mount: lost mount"); 864 VOP_UNLOCK(newdp, 0); 865 VOP_UNLOCK(vp, 0); 866 mountcheckdirs(vp, newdp); 867 vrele(newdp); 868 if ((mp->mnt_flag & MNT_RDONLY) == 0) 869 vfs_allocate_syncvnode(mp); 870 vfs_unbusy(mp); 871 return (0); 872 } 873 874 /* 875 * vfs_domount_update(): update of mounted file system 876 */ 877 static int 878 vfs_domount_update( 879 struct thread *td, /* Calling thread. */ 880 struct vnode *vp, /* Mount point vnode. */ 881 uint64_t fsflags, /* Flags common to all filesystems. */ 882 struct vfsoptlist **optlist /* Options local to the filesystem. */ 883 ) 884 { 885 struct oexport_args oexport; 886 struct export_args export; 887 struct mount *mp; 888 int error, export_error; 889 uint64_t flag; 890 891 mtx_assert(&Giant, MA_OWNED); 892 ASSERT_VOP_ELOCKED(vp, __func__); 893 KASSERT((fsflags & MNT_UPDATE) != 0, ("MNT_UPDATE should be here")); 894 895 if ((vp->v_vflag & VV_ROOT) == 0) { 896 vput(vp); 897 return (EINVAL); 898 } 899 mp = vp->v_mount; 900 /* 901 * We only allow the filesystem to be reloaded if it 902 * is currently mounted read-only. 903 */ 904 flag = mp->mnt_flag; 905 if ((fsflags & MNT_RELOAD) != 0 && (flag & MNT_RDONLY) == 0) { 906 vput(vp); 907 return (EOPNOTSUPP); /* Needs translation */ 908 } 909 /* 910 * Only privileged root, or (if MNT_USER is set) the user that 911 * did the original mount is permitted to update it. 912 */ 913 error = vfs_suser(mp, td); 914 if (error != 0) { 915 vput(vp); 916 return (error); 917 } 918 if (vfs_busy(mp, MBF_NOWAIT)) { 919 vput(vp); 920 return (EBUSY); 921 } 922 VI_LOCK(vp); 923 if ((vp->v_iflag & VI_MOUNT) != 0 || vp->v_mountedhere != NULL) { 924 VI_UNLOCK(vp); 925 vfs_unbusy(mp); 926 vput(vp); 927 return (EBUSY); 928 } 929 vp->v_iflag |= VI_MOUNT; 930 VI_UNLOCK(vp); 931 VOP_UNLOCK(vp, 0); 932 933 MNT_ILOCK(mp); 934 mp->mnt_flag &= ~MNT_UPDATEMASK; 935 mp->mnt_flag |= fsflags & (MNT_RELOAD | MNT_FORCE | MNT_UPDATE | 936 MNT_SNAPSHOT | MNT_ROOTFS | MNT_UPDATEMASK | MNT_RDONLY); 937 if ((mp->mnt_flag & MNT_ASYNC) == 0) 938 mp->mnt_kern_flag &= ~MNTK_ASYNC; 939 MNT_IUNLOCK(mp); 940 mp->mnt_optnew = *optlist; 941 vfs_mergeopts(mp->mnt_optnew, mp->mnt_opt); 942 943 /* 944 * Mount the filesystem. 945 * XXX The final recipients of VFS_MOUNT just overwrite the ndp they 946 * get. No freeing of cn_pnbuf. 947 */ 948 error = VFS_MOUNT(mp); 949 950 export_error = 0; 951 if (error == 0) { 952 /* Process the export option. */ 953 if (vfs_copyopt(mp->mnt_optnew, "export", &export, 954 sizeof(export)) == 0) { 955 export_error = vfs_export(mp, &export); 956 } else if (vfs_copyopt(mp->mnt_optnew, "export", &oexport, 957 sizeof(oexport)) == 0) { 958 export.ex_flags = oexport.ex_flags; 959 export.ex_root = oexport.ex_root; 960 export.ex_anon = oexport.ex_anon; 961 export.ex_addr = oexport.ex_addr; 962 export.ex_addrlen = oexport.ex_addrlen; 963 export.ex_mask = oexport.ex_mask; 964 export.ex_masklen = oexport.ex_masklen; 965 export.ex_indexfile = oexport.ex_indexfile; 966 export.ex_numsecflavors = 0; 967 export_error = vfs_export(mp, &export); 968 } 969 } 970 971 MNT_ILOCK(mp); 972 if (error == 0) { 973 mp->mnt_flag &= ~(MNT_UPDATE | MNT_RELOAD | MNT_FORCE | 974 MNT_SNAPSHOT); 975 } else { 976 /* 977 * If we fail, restore old mount flags. MNT_QUOTA is special, 978 * because it is not part of MNT_UPDATEMASK, but it could have 979 * changed in the meantime if quotactl(2) was called. 980 * All in all we want current value of MNT_QUOTA, not the old 981 * one. 982 */ 983 mp->mnt_flag = (mp->mnt_flag & MNT_QUOTA) | (flag & ~MNT_QUOTA); 984 } 985 if ((mp->mnt_flag & MNT_ASYNC) != 0 && 986 (mp->mnt_kern_flag & MNTK_NOASYNC) == 0) 987 mp->mnt_kern_flag |= MNTK_ASYNC; 988 else 989 mp->mnt_kern_flag &= ~MNTK_ASYNC; 990 MNT_IUNLOCK(mp); 991 992 if (error != 0) 993 goto end; 994 995 if (mp->mnt_opt != NULL) 996 vfs_freeopts(mp->mnt_opt); 997 mp->mnt_opt = mp->mnt_optnew; 998 *optlist = NULL; 999 (void)VFS_STATFS(mp, &mp->mnt_stat); 1000 /* 1001 * Prevent external consumers of mount options from reading 1002 * mnt_optnew. 1003 */ 1004 mp->mnt_optnew = NULL; 1005 1006 if ((mp->mnt_flag & MNT_RDONLY) == 0) 1007 vfs_allocate_syncvnode(mp); 1008 else 1009 vfs_deallocate_syncvnode(mp); 1010 end: 1011 vfs_unbusy(mp); 1012 VI_LOCK(vp); 1013 vp->v_iflag &= ~VI_MOUNT; 1014 VI_UNLOCK(vp); 1015 vrele(vp); 1016 return (error != 0 ? error : export_error); 1017 } 1018 1019 /* 1020 * vfs_domount(): actually attempt a filesystem mount. 1021 */ 1022 static int 1023 vfs_domount( 1024 struct thread *td, /* Calling thread. */ 1025 const char *fstype, /* Filesystem type. */ 1026 char *fspath, /* Mount path. */ 1027 uint64_t fsflags, /* Flags common to all filesystems. */ 1028 struct vfsoptlist **optlist /* Options local to the filesystem. */ 1029 ) 1030 { 1031 struct vfsconf *vfsp; 1032 struct nameidata nd; 1033 struct vnode *vp; 1034 char *pathbuf; 1035 int error; 1036 1037 /* 1038 * Be ultra-paranoid about making sure the type and fspath 1039 * variables will fit in our mp buffers, including the 1040 * terminating NUL. 1041 */ 1042 if (strlen(fstype) >= MFSNAMELEN || strlen(fspath) >= MNAMELEN) 1043 return (ENAMETOOLONG); 1044 1045 if (jailed(td->td_ucred) || usermount == 0) { 1046 if ((error = priv_check(td, PRIV_VFS_MOUNT)) != 0) 1047 return (error); 1048 } 1049 1050 /* 1051 * Do not allow NFS export or MNT_SUIDDIR by unprivileged users. 1052 */ 1053 if (fsflags & MNT_EXPORTED) { 1054 error = priv_check(td, PRIV_VFS_MOUNT_EXPORTED); 1055 if (error) 1056 return (error); 1057 } 1058 if (fsflags & MNT_SUIDDIR) { 1059 error = priv_check(td, PRIV_VFS_MOUNT_SUIDDIR); 1060 if (error) 1061 return (error); 1062 } 1063 /* 1064 * Silently enforce MNT_NOSUID and MNT_USER for unprivileged users. 1065 */ 1066 if ((fsflags & (MNT_NOSUID | MNT_USER)) != (MNT_NOSUID | MNT_USER)) { 1067 if (priv_check(td, PRIV_VFS_MOUNT_NONUSER) != 0) 1068 fsflags |= MNT_NOSUID | MNT_USER; 1069 } 1070 1071 /* Load KLDs before we lock the covered vnode to avoid reversals. */ 1072 vfsp = NULL; 1073 if ((fsflags & MNT_UPDATE) == 0) { 1074 /* Don't try to load KLDs if we're mounting the root. */ 1075 if (fsflags & MNT_ROOTFS) 1076 vfsp = vfs_byname(fstype); 1077 else 1078 vfsp = vfs_byname_kld(fstype, td, &error); 1079 if (vfsp == NULL) 1080 return (ENODEV); 1081 if (jailed(td->td_ucred) && !(vfsp->vfc_flags & VFCF_JAIL)) 1082 return (EPERM); 1083 } 1084 1085 /* 1086 * Get vnode to be covered or mount point's vnode in case of MNT_UPDATE. 1087 */ 1088 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, 1089 UIO_SYSSPACE, fspath, td); 1090 error = namei(&nd); 1091 if (error != 0) 1092 return (error); 1093 mtx_lock(&Giant); 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 mtx_unlock(&Giant); 1109 1110 ASSERT_VI_UNLOCKED(vp, __func__); 1111 ASSERT_VOP_UNLOCKED(vp, __func__); 1112 1113 return (error); 1114 } 1115 1116 /* 1117 * Unmount a filesystem. 1118 * 1119 * Note: unmount takes a path to the vnode mounted on as argument, not 1120 * special file (as before). 1121 */ 1122 #ifndef _SYS_SYSPROTO_H_ 1123 struct unmount_args { 1124 char *path; 1125 int flags; 1126 }; 1127 #endif 1128 /* ARGSUSED */ 1129 int 1130 sys_unmount(td, uap) 1131 struct thread *td; 1132 register struct unmount_args /* { 1133 char *path; 1134 int flags; 1135 } */ *uap; 1136 { 1137 struct nameidata nd; 1138 struct mount *mp; 1139 char *pathbuf; 1140 int error, id0, id1; 1141 1142 AUDIT_ARG_VALUE(uap->flags); 1143 if (jailed(td->td_ucred) || usermount == 0) { 1144 error = priv_check(td, PRIV_VFS_UNMOUNT); 1145 if (error) 1146 return (error); 1147 } 1148 1149 pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK); 1150 error = copyinstr(uap->path, pathbuf, MNAMELEN, NULL); 1151 if (error) { 1152 free(pathbuf, M_TEMP); 1153 return (error); 1154 } 1155 mtx_lock(&Giant); 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 mtx_unlock(&Giant); 1161 free(pathbuf, M_TEMP); 1162 return (EINVAL); 1163 } 1164 1165 mtx_lock(&mountlist_mtx); 1166 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1167 if (mp->mnt_stat.f_fsid.val[0] == id0 && 1168 mp->mnt_stat.f_fsid.val[1] == id1) 1169 break; 1170 } 1171 mtx_unlock(&mountlist_mtx); 1172 } else { 1173 /* 1174 * Try to find global path for path argument. 1175 */ 1176 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, 1177 UIO_SYSSPACE, pathbuf, td); 1178 if (namei(&nd) == 0) { 1179 NDFREE(&nd, NDF_ONLY_PNBUF); 1180 error = vn_path_to_global_path(td, nd.ni_vp, pathbuf, 1181 MNAMELEN); 1182 if (error == 0 || error == ENODEV) 1183 vput(nd.ni_vp); 1184 } 1185 mtx_lock(&mountlist_mtx); 1186 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1187 if (strcmp(mp->mnt_stat.f_mntonname, pathbuf) == 0) 1188 break; 1189 } 1190 mtx_unlock(&mountlist_mtx); 1191 } 1192 free(pathbuf, M_TEMP); 1193 if (mp == NULL) { 1194 /* 1195 * Previously we returned ENOENT for a nonexistent path and 1196 * EINVAL for a non-mountpoint. We cannot tell these apart 1197 * now, so in the !MNT_BYFSID case return the more likely 1198 * EINVAL for compatibility. 1199 */ 1200 mtx_unlock(&Giant); 1201 return ((uap->flags & MNT_BYFSID) ? ENOENT : EINVAL); 1202 } 1203 1204 /* 1205 * Don't allow unmounting the root filesystem. 1206 */ 1207 if (mp->mnt_flag & MNT_ROOTFS) { 1208 mtx_unlock(&Giant); 1209 return (EINVAL); 1210 } 1211 error = dounmount(mp, uap->flags, td); 1212 mtx_unlock(&Giant); 1213 return (error); 1214 } 1215 1216 /* 1217 * Do the actual filesystem unmount. 1218 */ 1219 int 1220 dounmount(mp, flags, td) 1221 struct mount *mp; 1222 int flags; 1223 struct thread *td; 1224 { 1225 struct vnode *coveredvp, *fsrootvp; 1226 int error; 1227 uint64_t async_flag; 1228 int mnt_gen_r; 1229 1230 mtx_assert(&Giant, MA_OWNED); 1231 1232 if ((coveredvp = mp->mnt_vnodecovered) != NULL) { 1233 mnt_gen_r = mp->mnt_gen; 1234 VI_LOCK(coveredvp); 1235 vholdl(coveredvp); 1236 vn_lock(coveredvp, LK_EXCLUSIVE | LK_INTERLOCK | LK_RETRY); 1237 vdrop(coveredvp); 1238 /* 1239 * Check for mp being unmounted while waiting for the 1240 * covered vnode lock. 1241 */ 1242 if (coveredvp->v_mountedhere != mp || 1243 coveredvp->v_mountedhere->mnt_gen != mnt_gen_r) { 1244 VOP_UNLOCK(coveredvp, 0); 1245 return (EBUSY); 1246 } 1247 } 1248 /* 1249 * Only privileged root, or (if MNT_USER is set) the user that did the 1250 * original mount is permitted to unmount this filesystem. 1251 */ 1252 error = vfs_suser(mp, td); 1253 if (error) { 1254 if (coveredvp) 1255 VOP_UNLOCK(coveredvp, 0); 1256 return (error); 1257 } 1258 1259 vn_start_write(NULL, &mp, V_WAIT); 1260 MNT_ILOCK(mp); 1261 if ((mp->mnt_kern_flag & MNTK_UNMOUNT) != 0 || 1262 !TAILQ_EMPTY(&mp->mnt_uppers)) { 1263 MNT_IUNLOCK(mp); 1264 if (coveredvp) 1265 VOP_UNLOCK(coveredvp, 0); 1266 vn_finished_write(mp); 1267 return (EBUSY); 1268 } 1269 mp->mnt_kern_flag |= MNTK_UNMOUNT | MNTK_NOINSMNTQ; 1270 /* Allow filesystems to detect that a forced unmount is in progress. */ 1271 if (flags & MNT_FORCE) 1272 mp->mnt_kern_flag |= MNTK_UNMOUNTF; 1273 error = 0; 1274 if (mp->mnt_lockref) { 1275 mp->mnt_kern_flag |= MNTK_DRAINING; 1276 error = msleep(&mp->mnt_lockref, MNT_MTX(mp), PVFS, 1277 "mount drain", 0); 1278 } 1279 MNT_IUNLOCK(mp); 1280 KASSERT(mp->mnt_lockref == 0, 1281 ("%s: invalid lock refcount in the drain path @ %s:%d", 1282 __func__, __FILE__, __LINE__)); 1283 KASSERT(error == 0, 1284 ("%s: invalid return value for msleep in the drain path @ %s:%d", 1285 __func__, __FILE__, __LINE__)); 1286 1287 if (mp->mnt_flag & MNT_EXPUBLIC) 1288 vfs_setpublicfs(NULL, NULL, NULL); 1289 1290 vfs_msync(mp, MNT_WAIT); 1291 MNT_ILOCK(mp); 1292 async_flag = mp->mnt_flag & MNT_ASYNC; 1293 mp->mnt_flag &= ~MNT_ASYNC; 1294 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1295 MNT_IUNLOCK(mp); 1296 cache_purgevfs(mp); /* remove cache entries for this file sys */ 1297 vfs_deallocate_syncvnode(mp); 1298 /* 1299 * For forced unmounts, move process cdir/rdir refs on the fs root 1300 * vnode to the covered vnode. For non-forced unmounts we want 1301 * such references to cause an EBUSY error. 1302 */ 1303 if ((flags & MNT_FORCE) && 1304 VFS_ROOT(mp, LK_EXCLUSIVE, &fsrootvp) == 0) { 1305 if (mp->mnt_vnodecovered != NULL) 1306 mountcheckdirs(fsrootvp, mp->mnt_vnodecovered); 1307 if (fsrootvp == rootvnode) { 1308 vrele(rootvnode); 1309 rootvnode = NULL; 1310 } 1311 vput(fsrootvp); 1312 } 1313 if (((mp->mnt_flag & MNT_RDONLY) || 1314 (error = VFS_SYNC(mp, MNT_WAIT)) == 0) || (flags & MNT_FORCE) != 0) 1315 error = VFS_UNMOUNT(mp, flags); 1316 vn_finished_write(mp); 1317 /* 1318 * If we failed to flush the dirty blocks for this mount point, 1319 * undo all the cdir/rdir and rootvnode changes we made above. 1320 * Unless we failed to do so because the device is reporting that 1321 * it doesn't exist anymore. 1322 */ 1323 if (error && error != ENXIO) { 1324 if ((flags & MNT_FORCE) && 1325 VFS_ROOT(mp, LK_EXCLUSIVE, &fsrootvp) == 0) { 1326 if (mp->mnt_vnodecovered != NULL) 1327 mountcheckdirs(mp->mnt_vnodecovered, fsrootvp); 1328 if (rootvnode == NULL) { 1329 rootvnode = fsrootvp; 1330 vref(rootvnode); 1331 } 1332 vput(fsrootvp); 1333 } 1334 MNT_ILOCK(mp); 1335 mp->mnt_kern_flag &= ~MNTK_NOINSMNTQ; 1336 if ((mp->mnt_flag & MNT_RDONLY) == 0) { 1337 MNT_IUNLOCK(mp); 1338 vfs_allocate_syncvnode(mp); 1339 MNT_ILOCK(mp); 1340 } 1341 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 1342 mp->mnt_flag |= async_flag; 1343 if ((mp->mnt_flag & MNT_ASYNC) != 0 && 1344 (mp->mnt_kern_flag & MNTK_NOASYNC) == 0) 1345 mp->mnt_kern_flag |= MNTK_ASYNC; 1346 if (mp->mnt_kern_flag & MNTK_MWAIT) { 1347 mp->mnt_kern_flag &= ~MNTK_MWAIT; 1348 wakeup(mp); 1349 } 1350 MNT_IUNLOCK(mp); 1351 if (coveredvp) 1352 VOP_UNLOCK(coveredvp, 0); 1353 return (error); 1354 } 1355 mtx_lock(&mountlist_mtx); 1356 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1357 mtx_unlock(&mountlist_mtx); 1358 if (coveredvp != NULL) { 1359 coveredvp->v_mountedhere = NULL; 1360 vput(coveredvp); 1361 } 1362 vfs_event_signal(NULL, VQ_UNMOUNT, 0); 1363 vfs_mount_destroy(mp); 1364 return (0); 1365 } 1366 1367 /* 1368 * Report errors during filesystem mounting. 1369 */ 1370 void 1371 vfs_mount_error(struct mount *mp, const char *fmt, ...) 1372 { 1373 struct vfsoptlist *moptlist = mp->mnt_optnew; 1374 va_list ap; 1375 int error, len; 1376 char *errmsg; 1377 1378 error = vfs_getopt(moptlist, "errmsg", (void **)&errmsg, &len); 1379 if (error || errmsg == NULL || len <= 0) 1380 return; 1381 1382 va_start(ap, fmt); 1383 vsnprintf(errmsg, (size_t)len, fmt, ap); 1384 va_end(ap); 1385 } 1386 1387 void 1388 vfs_opterror(struct vfsoptlist *opts, const char *fmt, ...) 1389 { 1390 va_list ap; 1391 int error, len; 1392 char *errmsg; 1393 1394 error = vfs_getopt(opts, "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 /* 1404 * --------------------------------------------------------------------- 1405 * Functions for querying mount options/arguments from filesystems. 1406 */ 1407 1408 /* 1409 * Check that no unknown options are given 1410 */ 1411 int 1412 vfs_filteropt(struct vfsoptlist *opts, const char **legal) 1413 { 1414 struct vfsopt *opt; 1415 char errmsg[255]; 1416 const char **t, *p, *q; 1417 int ret = 0; 1418 1419 TAILQ_FOREACH(opt, opts, link) { 1420 p = opt->name; 1421 q = NULL; 1422 if (p[0] == 'n' && p[1] == 'o') 1423 q = p + 2; 1424 for(t = global_opts; *t != NULL; t++) { 1425 if (strcmp(*t, p) == 0) 1426 break; 1427 if (q != NULL) { 1428 if (strcmp(*t, q) == 0) 1429 break; 1430 } 1431 } 1432 if (*t != NULL) 1433 continue; 1434 for(t = legal; *t != NULL; t++) { 1435 if (strcmp(*t, p) == 0) 1436 break; 1437 if (q != NULL) { 1438 if (strcmp(*t, q) == 0) 1439 break; 1440 } 1441 } 1442 if (*t != NULL) 1443 continue; 1444 snprintf(errmsg, sizeof(errmsg), 1445 "mount option <%s> is unknown", p); 1446 ret = EINVAL; 1447 } 1448 if (ret != 0) { 1449 TAILQ_FOREACH(opt, opts, link) { 1450 if (strcmp(opt->name, "errmsg") == 0) { 1451 strncpy((char *)opt->value, errmsg, opt->len); 1452 break; 1453 } 1454 } 1455 if (opt == NULL) 1456 printf("%s\n", errmsg); 1457 } 1458 return (ret); 1459 } 1460 1461 /* 1462 * Get a mount option by its name. 1463 * 1464 * Return 0 if the option was found, ENOENT otherwise. 1465 * If len is non-NULL it will be filled with the length 1466 * of the option. If buf is non-NULL, it will be filled 1467 * with the address of the option. 1468 */ 1469 int 1470 vfs_getopt(opts, name, buf, len) 1471 struct vfsoptlist *opts; 1472 const char *name; 1473 void **buf; 1474 int *len; 1475 { 1476 struct vfsopt *opt; 1477 1478 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1479 1480 TAILQ_FOREACH(opt, opts, link) { 1481 if (strcmp(name, opt->name) == 0) { 1482 opt->seen = 1; 1483 if (len != NULL) 1484 *len = opt->len; 1485 if (buf != NULL) 1486 *buf = opt->value; 1487 return (0); 1488 } 1489 } 1490 return (ENOENT); 1491 } 1492 1493 int 1494 vfs_getopt_pos(struct vfsoptlist *opts, const char *name) 1495 { 1496 struct vfsopt *opt; 1497 1498 if (opts == NULL) 1499 return (-1); 1500 1501 TAILQ_FOREACH(opt, opts, link) { 1502 if (strcmp(name, opt->name) == 0) { 1503 opt->seen = 1; 1504 return (opt->pos); 1505 } 1506 } 1507 return (-1); 1508 } 1509 1510 int 1511 vfs_getopt_size(struct vfsoptlist *opts, const char *name, off_t *value) 1512 { 1513 char *opt_value, *vtp; 1514 quad_t iv; 1515 int error, opt_len; 1516 1517 error = vfs_getopt(opts, name, (void **)&opt_value, &opt_len); 1518 if (error != 0) 1519 return (error); 1520 if (opt_len == 0 || opt_value == NULL) 1521 return (EINVAL); 1522 if (opt_value[0] == '\0' || opt_value[opt_len - 1] != '\0') 1523 return (EINVAL); 1524 iv = strtoq(opt_value, &vtp, 0); 1525 if (vtp == opt_value || (vtp[0] != '\0' && vtp[1] != '\0')) 1526 return (EINVAL); 1527 if (iv < 0) 1528 return (EINVAL); 1529 switch (vtp[0]) { 1530 case 't': 1531 case 'T': 1532 iv *= 1024; 1533 case 'g': 1534 case 'G': 1535 iv *= 1024; 1536 case 'm': 1537 case 'M': 1538 iv *= 1024; 1539 case 'k': 1540 case 'K': 1541 iv *= 1024; 1542 case '\0': 1543 break; 1544 default: 1545 return (EINVAL); 1546 } 1547 *value = iv; 1548 1549 return (0); 1550 } 1551 1552 char * 1553 vfs_getopts(struct vfsoptlist *opts, const char *name, int *error) 1554 { 1555 struct vfsopt *opt; 1556 1557 *error = 0; 1558 TAILQ_FOREACH(opt, opts, link) { 1559 if (strcmp(name, opt->name) != 0) 1560 continue; 1561 opt->seen = 1; 1562 if (opt->len == 0 || 1563 ((char *)opt->value)[opt->len - 1] != '\0') { 1564 *error = EINVAL; 1565 return (NULL); 1566 } 1567 return (opt->value); 1568 } 1569 *error = ENOENT; 1570 return (NULL); 1571 } 1572 1573 int 1574 vfs_flagopt(struct vfsoptlist *opts, const char *name, uint64_t *w, 1575 uint64_t val) 1576 { 1577 struct vfsopt *opt; 1578 1579 TAILQ_FOREACH(opt, opts, link) { 1580 if (strcmp(name, opt->name) == 0) { 1581 opt->seen = 1; 1582 if (w != NULL) 1583 *w |= val; 1584 return (1); 1585 } 1586 } 1587 if (w != NULL) 1588 *w &= ~val; 1589 return (0); 1590 } 1591 1592 int 1593 vfs_scanopt(struct vfsoptlist *opts, const char *name, const char *fmt, ...) 1594 { 1595 va_list ap; 1596 struct vfsopt *opt; 1597 int ret; 1598 1599 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1600 1601 TAILQ_FOREACH(opt, opts, link) { 1602 if (strcmp(name, opt->name) != 0) 1603 continue; 1604 opt->seen = 1; 1605 if (opt->len == 0 || opt->value == NULL) 1606 return (0); 1607 if (((char *)opt->value)[opt->len - 1] != '\0') 1608 return (0); 1609 va_start(ap, fmt); 1610 ret = vsscanf(opt->value, fmt, ap); 1611 va_end(ap); 1612 return (ret); 1613 } 1614 return (0); 1615 } 1616 1617 int 1618 vfs_setopt(struct vfsoptlist *opts, const char *name, void *value, int len) 1619 { 1620 struct vfsopt *opt; 1621 1622 TAILQ_FOREACH(opt, opts, link) { 1623 if (strcmp(name, opt->name) != 0) 1624 continue; 1625 opt->seen = 1; 1626 if (opt->value == NULL) 1627 opt->len = len; 1628 else { 1629 if (opt->len != len) 1630 return (EINVAL); 1631 bcopy(value, opt->value, len); 1632 } 1633 return (0); 1634 } 1635 return (ENOENT); 1636 } 1637 1638 int 1639 vfs_setopt_part(struct vfsoptlist *opts, const char *name, void *value, int len) 1640 { 1641 struct vfsopt *opt; 1642 1643 TAILQ_FOREACH(opt, opts, link) { 1644 if (strcmp(name, opt->name) != 0) 1645 continue; 1646 opt->seen = 1; 1647 if (opt->value == NULL) 1648 opt->len = len; 1649 else { 1650 if (opt->len < len) 1651 return (EINVAL); 1652 opt->len = len; 1653 bcopy(value, opt->value, len); 1654 } 1655 return (0); 1656 } 1657 return (ENOENT); 1658 } 1659 1660 int 1661 vfs_setopts(struct vfsoptlist *opts, const char *name, const char *value) 1662 { 1663 struct vfsopt *opt; 1664 1665 TAILQ_FOREACH(opt, opts, link) { 1666 if (strcmp(name, opt->name) != 0) 1667 continue; 1668 opt->seen = 1; 1669 if (opt->value == NULL) 1670 opt->len = strlen(value) + 1; 1671 else if (strlcpy(opt->value, value, opt->len) >= opt->len) 1672 return (EINVAL); 1673 return (0); 1674 } 1675 return (ENOENT); 1676 } 1677 1678 /* 1679 * Find and copy a mount option. 1680 * 1681 * The size of the buffer has to be specified 1682 * in len, if it is not the same length as the 1683 * mount option, EINVAL is returned. 1684 * Returns ENOENT if the option is not found. 1685 */ 1686 int 1687 vfs_copyopt(opts, name, dest, len) 1688 struct vfsoptlist *opts; 1689 const char *name; 1690 void *dest; 1691 int len; 1692 { 1693 struct vfsopt *opt; 1694 1695 KASSERT(opts != NULL, ("vfs_copyopt: caller passed 'opts' as NULL")); 1696 1697 TAILQ_FOREACH(opt, opts, link) { 1698 if (strcmp(name, opt->name) == 0) { 1699 opt->seen = 1; 1700 if (len != opt->len) 1701 return (EINVAL); 1702 bcopy(opt->value, dest, opt->len); 1703 return (0); 1704 } 1705 } 1706 return (ENOENT); 1707 } 1708 1709 int 1710 __vfs_statfs(struct mount *mp, struct statfs *sbp) 1711 { 1712 int error; 1713 1714 error = mp->mnt_op->vfs_statfs(mp, &mp->mnt_stat); 1715 if (sbp != &mp->mnt_stat) 1716 *sbp = mp->mnt_stat; 1717 return (error); 1718 } 1719 1720 void 1721 vfs_mountedfrom(struct mount *mp, const char *from) 1722 { 1723 1724 bzero(mp->mnt_stat.f_mntfromname, sizeof mp->mnt_stat.f_mntfromname); 1725 strlcpy(mp->mnt_stat.f_mntfromname, from, 1726 sizeof mp->mnt_stat.f_mntfromname); 1727 } 1728 1729 /* 1730 * --------------------------------------------------------------------- 1731 * This is the api for building mount args and mounting filesystems from 1732 * inside the kernel. 1733 * 1734 * The API works by accumulation of individual args. First error is 1735 * latched. 1736 * 1737 * XXX: should be documented in new manpage kernel_mount(9) 1738 */ 1739 1740 /* A memory allocation which must be freed when we are done */ 1741 struct mntaarg { 1742 SLIST_ENTRY(mntaarg) next; 1743 }; 1744 1745 /* The header for the mount arguments */ 1746 struct mntarg { 1747 struct iovec *v; 1748 int len; 1749 int error; 1750 SLIST_HEAD(, mntaarg) list; 1751 }; 1752 1753 /* 1754 * Add a boolean argument. 1755 * 1756 * flag is the boolean value. 1757 * name must start with "no". 1758 */ 1759 struct mntarg * 1760 mount_argb(struct mntarg *ma, int flag, const char *name) 1761 { 1762 1763 KASSERT(name[0] == 'n' && name[1] == 'o', 1764 ("mount_argb(...,%s): name must start with 'no'", name)); 1765 1766 return (mount_arg(ma, name + (flag ? 2 : 0), NULL, 0)); 1767 } 1768 1769 /* 1770 * Add an argument printf style 1771 */ 1772 struct mntarg * 1773 mount_argf(struct mntarg *ma, const char *name, const char *fmt, ...) 1774 { 1775 va_list ap; 1776 struct mntaarg *maa; 1777 struct sbuf *sb; 1778 int len; 1779 1780 if (ma == NULL) { 1781 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 1782 SLIST_INIT(&ma->list); 1783 } 1784 if (ma->error) 1785 return (ma); 1786 1787 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 1788 M_MOUNT, M_WAITOK); 1789 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 1790 ma->v[ma->len].iov_len = strlen(name) + 1; 1791 ma->len++; 1792 1793 sb = sbuf_new_auto(); 1794 va_start(ap, fmt); 1795 sbuf_vprintf(sb, fmt, ap); 1796 va_end(ap); 1797 sbuf_finish(sb); 1798 len = sbuf_len(sb) + 1; 1799 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 1800 SLIST_INSERT_HEAD(&ma->list, maa, next); 1801 bcopy(sbuf_data(sb), maa + 1, len); 1802 sbuf_delete(sb); 1803 1804 ma->v[ma->len].iov_base = maa + 1; 1805 ma->v[ma->len].iov_len = len; 1806 ma->len++; 1807 1808 return (ma); 1809 } 1810 1811 /* 1812 * Add an argument which is a userland string. 1813 */ 1814 struct mntarg * 1815 mount_argsu(struct mntarg *ma, const char *name, const void *val, int len) 1816 { 1817 struct mntaarg *maa; 1818 char *tbuf; 1819 1820 if (val == NULL) 1821 return (ma); 1822 if (ma == NULL) { 1823 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 1824 SLIST_INIT(&ma->list); 1825 } 1826 if (ma->error) 1827 return (ma); 1828 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 1829 SLIST_INSERT_HEAD(&ma->list, maa, next); 1830 tbuf = (void *)(maa + 1); 1831 ma->error = copyinstr(val, tbuf, len, NULL); 1832 return (mount_arg(ma, name, tbuf, -1)); 1833 } 1834 1835 /* 1836 * Plain argument. 1837 * 1838 * If length is -1, treat value as a C string. 1839 */ 1840 struct mntarg * 1841 mount_arg(struct mntarg *ma, const char *name, const void *val, int len) 1842 { 1843 1844 if (ma == NULL) { 1845 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 1846 SLIST_INIT(&ma->list); 1847 } 1848 if (ma->error) 1849 return (ma); 1850 1851 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 1852 M_MOUNT, M_WAITOK); 1853 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 1854 ma->v[ma->len].iov_len = strlen(name) + 1; 1855 ma->len++; 1856 1857 ma->v[ma->len].iov_base = (void *)(uintptr_t)val; 1858 if (len < 0) 1859 ma->v[ma->len].iov_len = strlen(val) + 1; 1860 else 1861 ma->v[ma->len].iov_len = len; 1862 ma->len++; 1863 return (ma); 1864 } 1865 1866 /* 1867 * Free a mntarg structure 1868 */ 1869 static void 1870 free_mntarg(struct mntarg *ma) 1871 { 1872 struct mntaarg *maa; 1873 1874 while (!SLIST_EMPTY(&ma->list)) { 1875 maa = SLIST_FIRST(&ma->list); 1876 SLIST_REMOVE_HEAD(&ma->list, next); 1877 free(maa, M_MOUNT); 1878 } 1879 free(ma->v, M_MOUNT); 1880 free(ma, M_MOUNT); 1881 } 1882 1883 /* 1884 * Mount a filesystem 1885 */ 1886 int 1887 kernel_mount(struct mntarg *ma, uint64_t flags) 1888 { 1889 struct uio auio; 1890 int error; 1891 1892 KASSERT(ma != NULL, ("kernel_mount NULL ma")); 1893 KASSERT(ma->v != NULL, ("kernel_mount NULL ma->v")); 1894 KASSERT(!(ma->len & 1), ("kernel_mount odd ma->len (%d)", ma->len)); 1895 1896 auio.uio_iov = ma->v; 1897 auio.uio_iovcnt = ma->len; 1898 auio.uio_segflg = UIO_SYSSPACE; 1899 1900 error = ma->error; 1901 if (!error) 1902 error = vfs_donmount(curthread, flags, &auio); 1903 free_mntarg(ma); 1904 return (error); 1905 } 1906 1907 /* 1908 * A printflike function to mount a filesystem. 1909 */ 1910 int 1911 kernel_vmount(int flags, ...) 1912 { 1913 struct mntarg *ma = NULL; 1914 va_list ap; 1915 const char *cp; 1916 const void *vp; 1917 int error; 1918 1919 va_start(ap, flags); 1920 for (;;) { 1921 cp = va_arg(ap, const char *); 1922 if (cp == NULL) 1923 break; 1924 vp = va_arg(ap, const void *); 1925 ma = mount_arg(ma, cp, vp, (vp != NULL ? -1 : 0)); 1926 } 1927 va_end(ap); 1928 1929 error = kernel_mount(ma, flags); 1930 return (error); 1931 } 1932 1933 void 1934 vfs_oexport_conv(const struct oexport_args *oexp, struct export_args *exp) 1935 { 1936 1937 bcopy(oexp, exp, sizeof(*oexp)); 1938 exp->ex_numsecflavors = 0; 1939 } 1940