1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1999-2004 Poul-Henning Kamp 5 * Copyright (c) 1999 Michael Smith 6 * Copyright (c) 1989, 1993 7 * The Regents of the University of California. All rights reserved. 8 * (c) UNIX System Laboratories, Inc. 9 * All or some portions of this file are derived from material licensed 10 * to the University of California by American Telephone and Telegraph 11 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 12 * the permission of UNIX System Laboratories, Inc. 13 * 14 * Redistribution and use in source and binary forms, with or without 15 * modification, are permitted provided that the following conditions 16 * are met: 17 * 1. Redistributions of source code must retain the above copyright 18 * notice, this list of conditions and the following disclaimer. 19 * 2. Redistributions in binary form must reproduce the above copyright 20 * notice, this list of conditions and the following disclaimer in the 21 * documentation and/or other materials provided with the distribution. 22 * 3. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 */ 38 39 #include <sys/cdefs.h> 40 __FBSDID("$FreeBSD$"); 41 42 #include <sys/param.h> 43 #include <sys/conf.h> 44 #include <sys/smp.h> 45 #include <sys/eventhandler.h> 46 #include <sys/fcntl.h> 47 #include <sys/jail.h> 48 #include <sys/kernel.h> 49 #include <sys/ktr.h> 50 #include <sys/libkern.h> 51 #include <sys/malloc.h> 52 #include <sys/mount.h> 53 #include <sys/mutex.h> 54 #include <sys/namei.h> 55 #include <sys/priv.h> 56 #include <sys/proc.h> 57 #include <sys/filedesc.h> 58 #include <sys/reboot.h> 59 #include <sys/sbuf.h> 60 #include <sys/syscallsubr.h> 61 #include <sys/sysproto.h> 62 #include <sys/sx.h> 63 #include <sys/sysctl.h> 64 #include <sys/sysent.h> 65 #include <sys/systm.h> 66 #include <sys/vnode.h> 67 #include <vm/uma.h> 68 69 #include <geom/geom.h> 70 71 #include <machine/stdarg.h> 72 73 #include <security/audit/audit.h> 74 #include <security/mac/mac_framework.h> 75 76 #define VFS_MOUNTARG_SIZE_MAX (1024 * 64) 77 78 static int vfs_domount(struct thread *td, const char *fstype, char *fspath, 79 uint64_t fsflags, struct vfsoptlist **optlist); 80 static void free_mntarg(struct mntarg *ma); 81 82 static int usermount = 0; 83 SYSCTL_INT(_vfs, OID_AUTO, usermount, CTLFLAG_RW, &usermount, 0, 84 "Unprivileged users may mount and unmount file systems"); 85 86 static bool default_autoro = false; 87 SYSCTL_BOOL(_vfs, OID_AUTO, default_autoro, CTLFLAG_RW, &default_autoro, 0, 88 "Retry failed r/w mount as r/o if no explicit ro/rw option is specified"); 89 90 MALLOC_DEFINE(M_MOUNT, "mount", "vfs mount structure"); 91 MALLOC_DEFINE(M_STATFS, "statfs", "statfs structure"); 92 static uma_zone_t mount_zone; 93 94 /* List of mounted filesystems. */ 95 struct mntlist mountlist = TAILQ_HEAD_INITIALIZER(mountlist); 96 97 /* For any iteration/modification of mountlist */ 98 struct mtx mountlist_mtx; 99 MTX_SYSINIT(mountlist, &mountlist_mtx, "mountlist", MTX_DEF); 100 101 EVENTHANDLER_LIST_DEFINE(vfs_mounted); 102 EVENTHANDLER_LIST_DEFINE(vfs_unmounted); 103 104 /* 105 * Global opts, taken by all filesystems 106 */ 107 static const char *global_opts[] = { 108 "errmsg", 109 "fstype", 110 "fspath", 111 "ro", 112 "rw", 113 "nosuid", 114 "noexec", 115 NULL 116 }; 117 118 static int 119 mount_init(void *mem, int size, int flags) 120 { 121 struct mount *mp; 122 123 mp = (struct mount *)mem; 124 mtx_init(&mp->mnt_mtx, "struct mount mtx", NULL, MTX_DEF); 125 mtx_init(&mp->mnt_listmtx, "struct mount vlist mtx", NULL, MTX_DEF); 126 lockinit(&mp->mnt_explock, PVFS, "explock", 0, 0); 127 mp->mnt_thread_in_ops_pcpu = uma_zalloc_pcpu(pcpu_zone_int, 128 M_WAITOK | M_ZERO); 129 mp->mnt_ref_pcpu = uma_zalloc_pcpu(pcpu_zone_int, 130 M_WAITOK | M_ZERO); 131 mp->mnt_lockref_pcpu = uma_zalloc_pcpu(pcpu_zone_int, 132 M_WAITOK | M_ZERO); 133 mp->mnt_writeopcount_pcpu = uma_zalloc_pcpu(pcpu_zone_int, 134 M_WAITOK | M_ZERO); 135 mp->mnt_ref = 0; 136 mp->mnt_vfs_ops = 1; 137 mp->mnt_rootvnode = NULL; 138 return (0); 139 } 140 141 static void 142 mount_fini(void *mem, int size) 143 { 144 struct mount *mp; 145 146 mp = (struct mount *)mem; 147 uma_zfree_pcpu(pcpu_zone_int, mp->mnt_writeopcount_pcpu); 148 uma_zfree_pcpu(pcpu_zone_int, mp->mnt_lockref_pcpu); 149 uma_zfree_pcpu(pcpu_zone_int, mp->mnt_ref_pcpu); 150 uma_zfree_pcpu(pcpu_zone_int, mp->mnt_thread_in_ops_pcpu); 151 lockdestroy(&mp->mnt_explock); 152 mtx_destroy(&mp->mnt_listmtx); 153 mtx_destroy(&mp->mnt_mtx); 154 } 155 156 static void 157 vfs_mount_init(void *dummy __unused) 158 { 159 160 mount_zone = uma_zcreate("Mountpoints", sizeof(struct mount), NULL, 161 NULL, mount_init, mount_fini, UMA_ALIGN_CACHE, UMA_ZONE_NOFREE); 162 } 163 SYSINIT(vfs_mount, SI_SUB_VFS, SI_ORDER_ANY, vfs_mount_init, NULL); 164 165 /* 166 * --------------------------------------------------------------------- 167 * Functions for building and sanitizing the mount options 168 */ 169 170 /* Remove one mount option. */ 171 static void 172 vfs_freeopt(struct vfsoptlist *opts, struct vfsopt *opt) 173 { 174 175 TAILQ_REMOVE(opts, opt, link); 176 free(opt->name, M_MOUNT); 177 if (opt->value != NULL) 178 free(opt->value, M_MOUNT); 179 free(opt, M_MOUNT); 180 } 181 182 /* Release all resources related to the mount options. */ 183 void 184 vfs_freeopts(struct vfsoptlist *opts) 185 { 186 struct vfsopt *opt; 187 188 while (!TAILQ_EMPTY(opts)) { 189 opt = TAILQ_FIRST(opts); 190 vfs_freeopt(opts, opt); 191 } 192 free(opts, M_MOUNT); 193 } 194 195 void 196 vfs_deleteopt(struct vfsoptlist *opts, const char *name) 197 { 198 struct vfsopt *opt, *temp; 199 200 if (opts == NULL) 201 return; 202 TAILQ_FOREACH_SAFE(opt, opts, link, temp) { 203 if (strcmp(opt->name, name) == 0) 204 vfs_freeopt(opts, opt); 205 } 206 } 207 208 static int 209 vfs_isopt_ro(const char *opt) 210 { 211 212 if (strcmp(opt, "ro") == 0 || strcmp(opt, "rdonly") == 0 || 213 strcmp(opt, "norw") == 0) 214 return (1); 215 return (0); 216 } 217 218 static int 219 vfs_isopt_rw(const char *opt) 220 { 221 222 if (strcmp(opt, "rw") == 0 || strcmp(opt, "noro") == 0) 223 return (1); 224 return (0); 225 } 226 227 /* 228 * Check if options are equal (with or without the "no" prefix). 229 */ 230 static int 231 vfs_equalopts(const char *opt1, const char *opt2) 232 { 233 char *p; 234 235 /* "opt" vs. "opt" or "noopt" vs. "noopt" */ 236 if (strcmp(opt1, opt2) == 0) 237 return (1); 238 /* "noopt" vs. "opt" */ 239 if (strncmp(opt1, "no", 2) == 0 && strcmp(opt1 + 2, opt2) == 0) 240 return (1); 241 /* "opt" vs. "noopt" */ 242 if (strncmp(opt2, "no", 2) == 0 && strcmp(opt1, opt2 + 2) == 0) 243 return (1); 244 while ((p = strchr(opt1, '.')) != NULL && 245 !strncmp(opt1, opt2, ++p - opt1)) { 246 opt2 += p - opt1; 247 opt1 = p; 248 /* "foo.noopt" vs. "foo.opt" */ 249 if (strncmp(opt1, "no", 2) == 0 && strcmp(opt1 + 2, opt2) == 0) 250 return (1); 251 /* "foo.opt" vs. "foo.noopt" */ 252 if (strncmp(opt2, "no", 2) == 0 && strcmp(opt1, opt2 + 2) == 0) 253 return (1); 254 } 255 /* "ro" / "rdonly" / "norw" / "rw" / "noro" */ 256 if ((vfs_isopt_ro(opt1) || vfs_isopt_rw(opt1)) && 257 (vfs_isopt_ro(opt2) || vfs_isopt_rw(opt2))) 258 return (1); 259 return (0); 260 } 261 262 /* 263 * If a mount option is specified several times, 264 * (with or without the "no" prefix) only keep 265 * the last occurrence of it. 266 */ 267 static void 268 vfs_sanitizeopts(struct vfsoptlist *opts) 269 { 270 struct vfsopt *opt, *opt2, *tmp; 271 272 TAILQ_FOREACH_REVERSE(opt, opts, vfsoptlist, link) { 273 opt2 = TAILQ_PREV(opt, vfsoptlist, link); 274 while (opt2 != NULL) { 275 if (vfs_equalopts(opt->name, opt2->name)) { 276 tmp = TAILQ_PREV(opt2, vfsoptlist, link); 277 vfs_freeopt(opts, opt2); 278 opt2 = tmp; 279 } else { 280 opt2 = TAILQ_PREV(opt2, vfsoptlist, link); 281 } 282 } 283 } 284 } 285 286 /* 287 * Build a linked list of mount options from a struct uio. 288 */ 289 int 290 vfs_buildopts(struct uio *auio, struct vfsoptlist **options) 291 { 292 struct vfsoptlist *opts; 293 struct vfsopt *opt; 294 size_t memused, namelen, optlen; 295 unsigned int i, iovcnt; 296 int error; 297 298 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 299 TAILQ_INIT(opts); 300 memused = 0; 301 iovcnt = auio->uio_iovcnt; 302 for (i = 0; i < iovcnt; i += 2) { 303 namelen = auio->uio_iov[i].iov_len; 304 optlen = auio->uio_iov[i + 1].iov_len; 305 memused += sizeof(struct vfsopt) + optlen + namelen; 306 /* 307 * Avoid consuming too much memory, and attempts to overflow 308 * memused. 309 */ 310 if (memused > VFS_MOUNTARG_SIZE_MAX || 311 optlen > VFS_MOUNTARG_SIZE_MAX || 312 namelen > VFS_MOUNTARG_SIZE_MAX) { 313 error = EINVAL; 314 goto bad; 315 } 316 317 opt = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 318 opt->name = malloc(namelen, M_MOUNT, M_WAITOK); 319 opt->value = NULL; 320 opt->len = 0; 321 opt->pos = i / 2; 322 opt->seen = 0; 323 324 /* 325 * Do this early, so jumps to "bad" will free the current 326 * option. 327 */ 328 TAILQ_INSERT_TAIL(opts, opt, link); 329 330 if (auio->uio_segflg == UIO_SYSSPACE) { 331 bcopy(auio->uio_iov[i].iov_base, opt->name, namelen); 332 } else { 333 error = copyin(auio->uio_iov[i].iov_base, opt->name, 334 namelen); 335 if (error) 336 goto bad; 337 } 338 /* Ensure names are null-terminated strings. */ 339 if (namelen == 0 || opt->name[namelen - 1] != '\0') { 340 error = EINVAL; 341 goto bad; 342 } 343 if (optlen != 0) { 344 opt->len = optlen; 345 opt->value = malloc(optlen, M_MOUNT, M_WAITOK); 346 if (auio->uio_segflg == UIO_SYSSPACE) { 347 bcopy(auio->uio_iov[i + 1].iov_base, opt->value, 348 optlen); 349 } else { 350 error = copyin(auio->uio_iov[i + 1].iov_base, 351 opt->value, optlen); 352 if (error) 353 goto bad; 354 } 355 } 356 } 357 vfs_sanitizeopts(opts); 358 *options = opts; 359 return (0); 360 bad: 361 vfs_freeopts(opts); 362 return (error); 363 } 364 365 /* 366 * Merge the old mount options with the new ones passed 367 * in the MNT_UPDATE case. 368 * 369 * XXX: This function will keep a "nofoo" option in the new 370 * options. E.g, if the option's canonical name is "foo", 371 * "nofoo" ends up in the mount point's active options. 372 */ 373 static void 374 vfs_mergeopts(struct vfsoptlist *toopts, struct vfsoptlist *oldopts) 375 { 376 struct vfsopt *opt, *new; 377 378 TAILQ_FOREACH(opt, oldopts, link) { 379 new = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 380 new->name = strdup(opt->name, M_MOUNT); 381 if (opt->len != 0) { 382 new->value = malloc(opt->len, M_MOUNT, M_WAITOK); 383 bcopy(opt->value, new->value, opt->len); 384 } else 385 new->value = NULL; 386 new->len = opt->len; 387 new->seen = opt->seen; 388 TAILQ_INSERT_HEAD(toopts, new, link); 389 } 390 vfs_sanitizeopts(toopts); 391 } 392 393 /* 394 * Mount a filesystem. 395 */ 396 #ifndef _SYS_SYSPROTO_H_ 397 struct nmount_args { 398 struct iovec *iovp; 399 unsigned int iovcnt; 400 int flags; 401 }; 402 #endif 403 int 404 sys_nmount(struct thread *td, struct nmount_args *uap) 405 { 406 struct uio *auio; 407 int error; 408 u_int iovcnt; 409 uint64_t flags; 410 411 /* 412 * Mount flags are now 64-bits. On 32-bit archtectures only 413 * 32-bits are passed in, but from here on everything handles 414 * 64-bit flags correctly. 415 */ 416 flags = uap->flags; 417 418 AUDIT_ARG_FFLAGS(flags); 419 CTR4(KTR_VFS, "%s: iovp %p with iovcnt %d and flags %d", __func__, 420 uap->iovp, uap->iovcnt, flags); 421 422 /* 423 * Filter out MNT_ROOTFS. We do not want clients of nmount() in 424 * userspace to set this flag, but we must filter it out if we want 425 * MNT_UPDATE on the root file system to work. 426 * MNT_ROOTFS should only be set by the kernel when mounting its 427 * root file system. 428 */ 429 flags &= ~MNT_ROOTFS; 430 431 iovcnt = uap->iovcnt; 432 /* 433 * Check that we have an even number of iovec's 434 * and that we have at least two options. 435 */ 436 if ((iovcnt & 1) || (iovcnt < 4)) { 437 CTR2(KTR_VFS, "%s: failed for invalid iovcnt %d", __func__, 438 uap->iovcnt); 439 return (EINVAL); 440 } 441 442 error = copyinuio(uap->iovp, iovcnt, &auio); 443 if (error) { 444 CTR2(KTR_VFS, "%s: failed for invalid uio op with %d errno", 445 __func__, error); 446 return (error); 447 } 448 error = vfs_donmount(td, flags, auio); 449 450 free(auio, M_IOV); 451 return (error); 452 } 453 454 /* 455 * --------------------------------------------------------------------- 456 * Various utility functions 457 */ 458 459 void 460 vfs_ref(struct mount *mp) 461 { 462 463 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 464 if (vfs_op_thread_enter(mp)) { 465 vfs_mp_count_add_pcpu(mp, ref, 1); 466 vfs_op_thread_exit(mp); 467 return; 468 } 469 470 MNT_ILOCK(mp); 471 MNT_REF(mp); 472 MNT_IUNLOCK(mp); 473 } 474 475 void 476 vfs_rel(struct mount *mp) 477 { 478 479 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 480 if (vfs_op_thread_enter(mp)) { 481 vfs_mp_count_sub_pcpu(mp, ref, 1); 482 vfs_op_thread_exit(mp); 483 return; 484 } 485 486 MNT_ILOCK(mp); 487 MNT_REL(mp); 488 MNT_IUNLOCK(mp); 489 } 490 491 /* 492 * Allocate and initialize the mount point struct. 493 */ 494 struct mount * 495 vfs_mount_alloc(struct vnode *vp, struct vfsconf *vfsp, const char *fspath, 496 struct ucred *cred) 497 { 498 struct mount *mp; 499 500 mp = uma_zalloc(mount_zone, M_WAITOK); 501 bzero(&mp->mnt_startzero, 502 __rangeof(struct mount, mnt_startzero, mnt_endzero)); 503 TAILQ_INIT(&mp->mnt_nvnodelist); 504 mp->mnt_nvnodelistsize = 0; 505 TAILQ_INIT(&mp->mnt_lazyvnodelist); 506 mp->mnt_lazyvnodelistsize = 0; 507 if (mp->mnt_ref != 0 || mp->mnt_lockref != 0 || 508 mp->mnt_writeopcount != 0) 509 panic("%s: non-zero counters on new mp %p\n", __func__, mp); 510 if (mp->mnt_vfs_ops != 1) 511 panic("%s: vfs_ops should be 1 but %d found\n", __func__, 512 mp->mnt_vfs_ops); 513 (void) vfs_busy(mp, MBF_NOWAIT); 514 atomic_add_acq_int(&vfsp->vfc_refcount, 1); 515 mp->mnt_op = vfsp->vfc_vfsops; 516 mp->mnt_vfc = vfsp; 517 mp->mnt_stat.f_type = vfsp->vfc_typenum; 518 mp->mnt_gen++; 519 strlcpy(mp->mnt_stat.f_fstypename, vfsp->vfc_name, MFSNAMELEN); 520 mp->mnt_vnodecovered = vp; 521 mp->mnt_cred = crdup(cred); 522 mp->mnt_stat.f_owner = cred->cr_uid; 523 strlcpy(mp->mnt_stat.f_mntonname, fspath, MNAMELEN); 524 mp->mnt_iosize_max = DFLTPHYS; 525 #ifdef MAC 526 mac_mount_init(mp); 527 mac_mount_create(cred, mp); 528 #endif 529 arc4rand(&mp->mnt_hashseed, sizeof mp->mnt_hashseed, 0); 530 TAILQ_INIT(&mp->mnt_uppers); 531 return (mp); 532 } 533 534 /* 535 * Destroy the mount struct previously allocated by vfs_mount_alloc(). 536 */ 537 void 538 vfs_mount_destroy(struct mount *mp) 539 { 540 541 if (mp->mnt_vfs_ops == 0) 542 panic("%s: entered with zero vfs_ops\n", __func__); 543 544 vfs_assert_mount_counters(mp); 545 546 MNT_ILOCK(mp); 547 mp->mnt_kern_flag |= MNTK_REFEXPIRE; 548 if (mp->mnt_kern_flag & MNTK_MWAIT) { 549 mp->mnt_kern_flag &= ~MNTK_MWAIT; 550 wakeup(mp); 551 } 552 while (mp->mnt_ref) 553 msleep(mp, MNT_MTX(mp), PVFS, "mntref", 0); 554 KASSERT(mp->mnt_ref == 0, 555 ("%s: invalid refcount in the drain path @ %s:%d", __func__, 556 __FILE__, __LINE__)); 557 if (mp->mnt_writeopcount != 0) 558 panic("vfs_mount_destroy: nonzero writeopcount"); 559 if (mp->mnt_secondary_writes != 0) 560 panic("vfs_mount_destroy: nonzero secondary_writes"); 561 atomic_subtract_rel_int(&mp->mnt_vfc->vfc_refcount, 1); 562 if (!TAILQ_EMPTY(&mp->mnt_nvnodelist)) { 563 struct vnode *vp; 564 565 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) 566 vn_printf(vp, "dangling vnode "); 567 panic("unmount: dangling vnode"); 568 } 569 KASSERT(TAILQ_EMPTY(&mp->mnt_uppers), ("mnt_uppers")); 570 if (mp->mnt_nvnodelistsize != 0) 571 panic("vfs_mount_destroy: nonzero nvnodelistsize"); 572 if (mp->mnt_lazyvnodelistsize != 0) 573 panic("vfs_mount_destroy: nonzero lazyvnodelistsize"); 574 if (mp->mnt_lockref != 0) 575 panic("vfs_mount_destroy: nonzero lock refcount"); 576 MNT_IUNLOCK(mp); 577 578 if (mp->mnt_vfs_ops != 1) 579 panic("%s: vfs_ops should be 1 but %d found\n", __func__, 580 mp->mnt_vfs_ops); 581 582 if (mp->mnt_rootvnode != NULL) 583 panic("%s: mount point still has a root vnode %p\n", __func__, 584 mp->mnt_rootvnode); 585 586 if (mp->mnt_vnodecovered != NULL) 587 vrele(mp->mnt_vnodecovered); 588 #ifdef MAC 589 mac_mount_destroy(mp); 590 #endif 591 if (mp->mnt_opt != NULL) 592 vfs_freeopts(mp->mnt_opt); 593 crfree(mp->mnt_cred); 594 uma_zfree(mount_zone, mp); 595 } 596 597 static bool 598 vfs_should_downgrade_to_ro_mount(uint64_t fsflags, int error) 599 { 600 /* This is an upgrade of an exisiting mount. */ 601 if ((fsflags & MNT_UPDATE) != 0) 602 return (false); 603 /* This is already an R/O mount. */ 604 if ((fsflags & MNT_RDONLY) != 0) 605 return (false); 606 607 switch (error) { 608 case ENODEV: /* generic, geom, ... */ 609 case EACCES: /* cam/scsi, ... */ 610 case EROFS: /* md, mmcsd, ... */ 611 /* 612 * These errors can be returned by the storage layer to signal 613 * that the media is read-only. No harm in the R/O mount 614 * attempt if the error was returned for some other reason. 615 */ 616 return (true); 617 default: 618 return (false); 619 } 620 } 621 622 int 623 vfs_donmount(struct thread *td, uint64_t fsflags, struct uio *fsoptions) 624 { 625 struct vfsoptlist *optlist; 626 struct vfsopt *opt, *tmp_opt; 627 char *fstype, *fspath, *errmsg; 628 int error, fstypelen, fspathlen, errmsg_len, errmsg_pos; 629 bool autoro; 630 631 errmsg = fspath = NULL; 632 errmsg_len = fspathlen = 0; 633 errmsg_pos = -1; 634 autoro = default_autoro; 635 636 error = vfs_buildopts(fsoptions, &optlist); 637 if (error) 638 return (error); 639 640 if (vfs_getopt(optlist, "errmsg", (void **)&errmsg, &errmsg_len) == 0) 641 errmsg_pos = vfs_getopt_pos(optlist, "errmsg"); 642 643 /* 644 * We need these two options before the others, 645 * and they are mandatory for any filesystem. 646 * Ensure they are NUL terminated as well. 647 */ 648 fstypelen = 0; 649 error = vfs_getopt(optlist, "fstype", (void **)&fstype, &fstypelen); 650 if (error || fstypelen <= 0 || fstype[fstypelen - 1] != '\0') { 651 error = EINVAL; 652 if (errmsg != NULL) 653 strncpy(errmsg, "Invalid fstype", errmsg_len); 654 goto bail; 655 } 656 fspathlen = 0; 657 error = vfs_getopt(optlist, "fspath", (void **)&fspath, &fspathlen); 658 if (error || fspathlen <= 0 || fspath[fspathlen - 1] != '\0') { 659 error = EINVAL; 660 if (errmsg != NULL) 661 strncpy(errmsg, "Invalid fspath", errmsg_len); 662 goto bail; 663 } 664 665 /* 666 * We need to see if we have the "update" option 667 * before we call vfs_domount(), since vfs_domount() has special 668 * logic based on MNT_UPDATE. This is very important 669 * when we want to update the root filesystem. 670 */ 671 TAILQ_FOREACH_SAFE(opt, optlist, link, tmp_opt) { 672 int do_freeopt = 0; 673 674 if (strcmp(opt->name, "update") == 0) { 675 fsflags |= MNT_UPDATE; 676 do_freeopt = 1; 677 } 678 else if (strcmp(opt->name, "async") == 0) 679 fsflags |= MNT_ASYNC; 680 else if (strcmp(opt->name, "force") == 0) { 681 fsflags |= MNT_FORCE; 682 do_freeopt = 1; 683 } 684 else if (strcmp(opt->name, "reload") == 0) { 685 fsflags |= MNT_RELOAD; 686 do_freeopt = 1; 687 } 688 else if (strcmp(opt->name, "multilabel") == 0) 689 fsflags |= MNT_MULTILABEL; 690 else if (strcmp(opt->name, "noasync") == 0) 691 fsflags &= ~MNT_ASYNC; 692 else if (strcmp(opt->name, "noatime") == 0) 693 fsflags |= MNT_NOATIME; 694 else if (strcmp(opt->name, "atime") == 0) { 695 free(opt->name, M_MOUNT); 696 opt->name = strdup("nonoatime", M_MOUNT); 697 } 698 else if (strcmp(opt->name, "noclusterr") == 0) 699 fsflags |= MNT_NOCLUSTERR; 700 else if (strcmp(opt->name, "clusterr") == 0) { 701 free(opt->name, M_MOUNT); 702 opt->name = strdup("nonoclusterr", M_MOUNT); 703 } 704 else if (strcmp(opt->name, "noclusterw") == 0) 705 fsflags |= MNT_NOCLUSTERW; 706 else if (strcmp(opt->name, "clusterw") == 0) { 707 free(opt->name, M_MOUNT); 708 opt->name = strdup("nonoclusterw", M_MOUNT); 709 } 710 else if (strcmp(opt->name, "noexec") == 0) 711 fsflags |= MNT_NOEXEC; 712 else if (strcmp(opt->name, "exec") == 0) { 713 free(opt->name, M_MOUNT); 714 opt->name = strdup("nonoexec", M_MOUNT); 715 } 716 else if (strcmp(opt->name, "nosuid") == 0) 717 fsflags |= MNT_NOSUID; 718 else if (strcmp(opt->name, "suid") == 0) { 719 free(opt->name, M_MOUNT); 720 opt->name = strdup("nonosuid", M_MOUNT); 721 } 722 else if (strcmp(opt->name, "nosymfollow") == 0) 723 fsflags |= MNT_NOSYMFOLLOW; 724 else if (strcmp(opt->name, "symfollow") == 0) { 725 free(opt->name, M_MOUNT); 726 opt->name = strdup("nonosymfollow", M_MOUNT); 727 } 728 else if (strcmp(opt->name, "noro") == 0) { 729 fsflags &= ~MNT_RDONLY; 730 autoro = false; 731 } 732 else if (strcmp(opt->name, "rw") == 0) { 733 fsflags &= ~MNT_RDONLY; 734 autoro = false; 735 } 736 else if (strcmp(opt->name, "ro") == 0) { 737 fsflags |= MNT_RDONLY; 738 autoro = false; 739 } 740 else if (strcmp(opt->name, "rdonly") == 0) { 741 free(opt->name, M_MOUNT); 742 opt->name = strdup("ro", M_MOUNT); 743 fsflags |= MNT_RDONLY; 744 autoro = false; 745 } 746 else if (strcmp(opt->name, "autoro") == 0) { 747 do_freeopt = 1; 748 autoro = true; 749 } 750 else if (strcmp(opt->name, "suiddir") == 0) 751 fsflags |= MNT_SUIDDIR; 752 else if (strcmp(opt->name, "sync") == 0) 753 fsflags |= MNT_SYNCHRONOUS; 754 else if (strcmp(opt->name, "union") == 0) 755 fsflags |= MNT_UNION; 756 else if (strcmp(opt->name, "automounted") == 0) { 757 fsflags |= MNT_AUTOMOUNTED; 758 do_freeopt = 1; 759 } else if (strcmp(opt->name, "nocover") == 0) { 760 fsflags |= MNT_NOCOVER; 761 do_freeopt = 1; 762 } else if (strcmp(opt->name, "cover") == 0) { 763 fsflags &= ~MNT_NOCOVER; 764 do_freeopt = 1; 765 } else if (strcmp(opt->name, "emptydir") == 0) { 766 fsflags |= MNT_EMPTYDIR; 767 do_freeopt = 1; 768 } else if (strcmp(opt->name, "noemptydir") == 0) { 769 fsflags &= ~MNT_EMPTYDIR; 770 do_freeopt = 1; 771 } 772 if (do_freeopt) 773 vfs_freeopt(optlist, opt); 774 } 775 776 /* 777 * Be ultra-paranoid about making sure the type and fspath 778 * variables will fit in our mp buffers, including the 779 * terminating NUL. 780 */ 781 if (fstypelen > MFSNAMELEN || fspathlen > MNAMELEN) { 782 error = ENAMETOOLONG; 783 goto bail; 784 } 785 786 error = vfs_domount(td, fstype, fspath, fsflags, &optlist); 787 788 /* 789 * See if we can mount in the read-only mode if the error code suggests 790 * that it could be possible and the mount options allow for that. 791 * Never try it if "[no]{ro|rw}" has been explicitly requested and not 792 * overridden by "autoro". 793 */ 794 if (autoro && vfs_should_downgrade_to_ro_mount(fsflags, error)) { 795 printf("%s: R/W mount failed, possibly R/O media," 796 " trying R/O mount\n", __func__); 797 fsflags |= MNT_RDONLY; 798 error = vfs_domount(td, fstype, fspath, fsflags, &optlist); 799 } 800 bail: 801 /* copyout the errmsg */ 802 if (errmsg_pos != -1 && ((2 * errmsg_pos + 1) < fsoptions->uio_iovcnt) 803 && errmsg_len > 0 && errmsg != NULL) { 804 if (fsoptions->uio_segflg == UIO_SYSSPACE) { 805 bcopy(errmsg, 806 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_base, 807 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_len); 808 } else { 809 copyout(errmsg, 810 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_base, 811 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_len); 812 } 813 } 814 815 if (optlist != NULL) 816 vfs_freeopts(optlist); 817 return (error); 818 } 819 820 /* 821 * Old mount API. 822 */ 823 #ifndef _SYS_SYSPROTO_H_ 824 struct mount_args { 825 char *type; 826 char *path; 827 int flags; 828 caddr_t data; 829 }; 830 #endif 831 /* ARGSUSED */ 832 int 833 sys_mount(struct thread *td, struct mount_args *uap) 834 { 835 char *fstype; 836 struct vfsconf *vfsp = NULL; 837 struct mntarg *ma = NULL; 838 uint64_t flags; 839 int error; 840 841 /* 842 * Mount flags are now 64-bits. On 32-bit architectures only 843 * 32-bits are passed in, but from here on everything handles 844 * 64-bit flags correctly. 845 */ 846 flags = uap->flags; 847 848 AUDIT_ARG_FFLAGS(flags); 849 850 /* 851 * Filter out MNT_ROOTFS. We do not want clients of mount() in 852 * userspace to set this flag, but we must filter it out if we want 853 * MNT_UPDATE on the root file system to work. 854 * MNT_ROOTFS should only be set by the kernel when mounting its 855 * root file system. 856 */ 857 flags &= ~MNT_ROOTFS; 858 859 fstype = malloc(MFSNAMELEN, M_TEMP, M_WAITOK); 860 error = copyinstr(uap->type, fstype, MFSNAMELEN, NULL); 861 if (error) { 862 free(fstype, M_TEMP); 863 return (error); 864 } 865 866 AUDIT_ARG_TEXT(fstype); 867 vfsp = vfs_byname_kld(fstype, td, &error); 868 free(fstype, M_TEMP); 869 if (vfsp == NULL) 870 return (ENOENT); 871 if (((vfsp->vfc_flags & VFCF_SBDRY) != 0 && 872 vfsp->vfc_vfsops_sd->vfs_cmount == NULL) || 873 ((vfsp->vfc_flags & VFCF_SBDRY) == 0 && 874 vfsp->vfc_vfsops->vfs_cmount == NULL)) 875 return (EOPNOTSUPP); 876 877 ma = mount_argsu(ma, "fstype", uap->type, MFSNAMELEN); 878 ma = mount_argsu(ma, "fspath", uap->path, MNAMELEN); 879 ma = mount_argb(ma, flags & MNT_RDONLY, "noro"); 880 ma = mount_argb(ma, !(flags & MNT_NOSUID), "nosuid"); 881 ma = mount_argb(ma, !(flags & MNT_NOEXEC), "noexec"); 882 883 if ((vfsp->vfc_flags & VFCF_SBDRY) != 0) 884 return (vfsp->vfc_vfsops_sd->vfs_cmount(ma, uap->data, flags)); 885 return (vfsp->vfc_vfsops->vfs_cmount(ma, uap->data, flags)); 886 } 887 888 /* 889 * vfs_domount_first(): first file system mount (not update) 890 */ 891 static int 892 vfs_domount_first( 893 struct thread *td, /* Calling thread. */ 894 struct vfsconf *vfsp, /* File system type. */ 895 char *fspath, /* Mount path. */ 896 struct vnode *vp, /* Vnode to be covered. */ 897 uint64_t fsflags, /* Flags common to all filesystems. */ 898 struct vfsoptlist **optlist /* Options local to the filesystem. */ 899 ) 900 { 901 struct vattr va; 902 struct mount *mp; 903 struct vnode *newdp; 904 int error, error1; 905 906 ASSERT_VOP_ELOCKED(vp, __func__); 907 KASSERT((fsflags & MNT_UPDATE) == 0, ("MNT_UPDATE shouldn't be here")); 908 909 if ((fsflags & MNT_EMPTYDIR) != 0) { 910 error = vfs_emptydir(vp); 911 if (error != 0) { 912 vput(vp); 913 return (error); 914 } 915 } 916 917 /* 918 * If the jail of the calling thread lacks permission for this type of 919 * file system, deny immediately. 920 */ 921 if (jailed(td->td_ucred) && !prison_allow(td->td_ucred, 922 vfsp->vfc_prison_flag)) { 923 vput(vp); 924 return (EPERM); 925 } 926 927 /* 928 * If the user is not root, ensure that they own the directory 929 * onto which we are attempting to mount. 930 */ 931 error = VOP_GETATTR(vp, &va, td->td_ucred); 932 if (error == 0 && va.va_uid != td->td_ucred->cr_uid) 933 error = priv_check_cred(td->td_ucred, PRIV_VFS_ADMIN); 934 if (error == 0) 935 error = vinvalbuf(vp, V_SAVE, 0, 0); 936 if (error == 0 && vp->v_type != VDIR) 937 error = ENOTDIR; 938 if (error == 0) { 939 VI_LOCK(vp); 940 if ((vp->v_iflag & VI_MOUNT) == 0 && vp->v_mountedhere == NULL) 941 vp->v_iflag |= VI_MOUNT; 942 else 943 error = EBUSY; 944 VI_UNLOCK(vp); 945 } 946 if (error != 0) { 947 vput(vp); 948 return (error); 949 } 950 VOP_UNLOCK(vp); 951 952 /* Allocate and initialize the filesystem. */ 953 mp = vfs_mount_alloc(vp, vfsp, fspath, td->td_ucred); 954 /* XXXMAC: pass to vfs_mount_alloc? */ 955 mp->mnt_optnew = *optlist; 956 /* Set the mount level flags. */ 957 mp->mnt_flag = (fsflags & (MNT_UPDATEMASK | MNT_ROOTFS | MNT_RDONLY)); 958 959 /* 960 * Mount the filesystem. 961 * XXX The final recipients of VFS_MOUNT just overwrite the ndp they 962 * get. No freeing of cn_pnbuf. 963 */ 964 error1 = 0; 965 if ((error = VFS_MOUNT(mp)) != 0 || 966 (error1 = VFS_STATFS(mp, &mp->mnt_stat)) != 0 || 967 (error1 = VFS_ROOT(mp, LK_EXCLUSIVE, &newdp)) != 0) { 968 if (error1 != 0) { 969 error = error1; 970 if ((error1 = VFS_UNMOUNT(mp, 0)) != 0) 971 printf("VFS_UNMOUNT returned %d\n", error1); 972 } 973 vfs_unbusy(mp); 974 mp->mnt_vnodecovered = NULL; 975 vfs_mount_destroy(mp); 976 VI_LOCK(vp); 977 vp->v_iflag &= ~VI_MOUNT; 978 VI_UNLOCK(vp); 979 vrele(vp); 980 return (error); 981 } 982 VOP_UNLOCK(newdp); 983 984 if (mp->mnt_opt != NULL) 985 vfs_freeopts(mp->mnt_opt); 986 mp->mnt_opt = mp->mnt_optnew; 987 *optlist = NULL; 988 989 /* 990 * Prevent external consumers of mount options from reading mnt_optnew. 991 */ 992 mp->mnt_optnew = NULL; 993 994 MNT_ILOCK(mp); 995 if ((mp->mnt_flag & MNT_ASYNC) != 0 && 996 (mp->mnt_kern_flag & MNTK_NOASYNC) == 0) 997 mp->mnt_kern_flag |= MNTK_ASYNC; 998 else 999 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1000 MNT_IUNLOCK(mp); 1001 1002 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1003 cache_purge(vp); 1004 VI_LOCK(vp); 1005 vp->v_iflag &= ~VI_MOUNT; 1006 VI_UNLOCK(vp); 1007 vp->v_mountedhere = mp; 1008 /* Place the new filesystem at the end of the mount list. */ 1009 mtx_lock(&mountlist_mtx); 1010 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 1011 mtx_unlock(&mountlist_mtx); 1012 vfs_event_signal(NULL, VQ_MOUNT, 0); 1013 vn_lock(newdp, LK_EXCLUSIVE | LK_RETRY); 1014 VOP_UNLOCK(vp); 1015 EVENTHANDLER_DIRECT_INVOKE(vfs_mounted, mp, newdp, td); 1016 VOP_UNLOCK(newdp); 1017 mountcheckdirs(vp, newdp); 1018 vrele(newdp); 1019 if ((mp->mnt_flag & MNT_RDONLY) == 0) 1020 vfs_allocate_syncvnode(mp); 1021 vfs_op_exit(mp); 1022 vfs_unbusy(mp); 1023 return (0); 1024 } 1025 1026 /* 1027 * vfs_domount_update(): update of mounted file system 1028 */ 1029 static int 1030 vfs_domount_update( 1031 struct thread *td, /* Calling thread. */ 1032 struct vnode *vp, /* Mount point vnode. */ 1033 uint64_t fsflags, /* Flags common to all filesystems. */ 1034 struct vfsoptlist **optlist /* Options local to the filesystem. */ 1035 ) 1036 { 1037 struct export_args export; 1038 struct vnode *rootvp; 1039 void *bufp; 1040 struct mount *mp; 1041 int error, export_error, len; 1042 uint64_t flag; 1043 1044 ASSERT_VOP_ELOCKED(vp, __func__); 1045 KASSERT((fsflags & MNT_UPDATE) != 0, ("MNT_UPDATE should be here")); 1046 mp = vp->v_mount; 1047 1048 if ((vp->v_vflag & VV_ROOT) == 0) { 1049 if (vfs_copyopt(*optlist, "export", &export, sizeof(export)) 1050 == 0) 1051 error = EXDEV; 1052 else 1053 error = EINVAL; 1054 vput(vp); 1055 return (error); 1056 } 1057 1058 /* 1059 * We only allow the filesystem to be reloaded if it 1060 * is currently mounted read-only. 1061 */ 1062 flag = mp->mnt_flag; 1063 if ((fsflags & MNT_RELOAD) != 0 && (flag & MNT_RDONLY) == 0) { 1064 vput(vp); 1065 return (EOPNOTSUPP); /* Needs translation */ 1066 } 1067 /* 1068 * Only privileged root, or (if MNT_USER is set) the user that 1069 * did the original mount is permitted to update it. 1070 */ 1071 error = vfs_suser(mp, td); 1072 if (error != 0) { 1073 vput(vp); 1074 return (error); 1075 } 1076 if (vfs_busy(mp, MBF_NOWAIT)) { 1077 vput(vp); 1078 return (EBUSY); 1079 } 1080 VI_LOCK(vp); 1081 if ((vp->v_iflag & VI_MOUNT) != 0 || vp->v_mountedhere != NULL) { 1082 VI_UNLOCK(vp); 1083 vfs_unbusy(mp); 1084 vput(vp); 1085 return (EBUSY); 1086 } 1087 vp->v_iflag |= VI_MOUNT; 1088 VI_UNLOCK(vp); 1089 VOP_UNLOCK(vp); 1090 1091 vfs_op_enter(mp); 1092 1093 MNT_ILOCK(mp); 1094 if ((mp->mnt_kern_flag & MNTK_UNMOUNT) != 0) { 1095 MNT_IUNLOCK(mp); 1096 error = EBUSY; 1097 goto end; 1098 } 1099 mp->mnt_flag &= ~MNT_UPDATEMASK; 1100 mp->mnt_flag |= fsflags & (MNT_RELOAD | MNT_FORCE | MNT_UPDATE | 1101 MNT_SNAPSHOT | MNT_ROOTFS | MNT_UPDATEMASK | MNT_RDONLY); 1102 if ((mp->mnt_flag & MNT_ASYNC) == 0) 1103 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1104 rootvp = vfs_cache_root_clear(mp); 1105 MNT_IUNLOCK(mp); 1106 if (rootvp != NULL) 1107 vrele(rootvp); 1108 mp->mnt_optnew = *optlist; 1109 vfs_mergeopts(mp->mnt_optnew, mp->mnt_opt); 1110 1111 /* 1112 * Mount the filesystem. 1113 * XXX The final recipients of VFS_MOUNT just overwrite the ndp they 1114 * get. No freeing of cn_pnbuf. 1115 */ 1116 error = VFS_MOUNT(mp); 1117 1118 export_error = 0; 1119 /* Process the export option. */ 1120 if (error == 0 && vfs_getopt(mp->mnt_optnew, "export", &bufp, 1121 &len) == 0) { 1122 /* Assume that there is only 1 ABI for each length. */ 1123 switch (len) { 1124 case (sizeof(struct oexport_args)): 1125 bzero(&export, sizeof(export)); 1126 /* FALLTHROUGH */ 1127 case (sizeof(export)): 1128 bcopy(bufp, &export, len); 1129 export_error = vfs_export(mp, &export); 1130 break; 1131 default: 1132 export_error = EINVAL; 1133 break; 1134 } 1135 } 1136 1137 MNT_ILOCK(mp); 1138 if (error == 0) { 1139 mp->mnt_flag &= ~(MNT_UPDATE | MNT_RELOAD | MNT_FORCE | 1140 MNT_SNAPSHOT); 1141 } else { 1142 /* 1143 * If we fail, restore old mount flags. MNT_QUOTA is special, 1144 * because it is not part of MNT_UPDATEMASK, but it could have 1145 * changed in the meantime if quotactl(2) was called. 1146 * All in all we want current value of MNT_QUOTA, not the old 1147 * one. 1148 */ 1149 mp->mnt_flag = (mp->mnt_flag & MNT_QUOTA) | (flag & ~MNT_QUOTA); 1150 } 1151 if ((mp->mnt_flag & MNT_ASYNC) != 0 && 1152 (mp->mnt_kern_flag & MNTK_NOASYNC) == 0) 1153 mp->mnt_kern_flag |= MNTK_ASYNC; 1154 else 1155 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1156 MNT_IUNLOCK(mp); 1157 1158 if (error != 0) 1159 goto end; 1160 1161 if (mp->mnt_opt != NULL) 1162 vfs_freeopts(mp->mnt_opt); 1163 mp->mnt_opt = mp->mnt_optnew; 1164 *optlist = NULL; 1165 (void)VFS_STATFS(mp, &mp->mnt_stat); 1166 /* 1167 * Prevent external consumers of mount options from reading 1168 * mnt_optnew. 1169 */ 1170 mp->mnt_optnew = NULL; 1171 1172 if ((mp->mnt_flag & MNT_RDONLY) == 0) 1173 vfs_allocate_syncvnode(mp); 1174 else 1175 vfs_deallocate_syncvnode(mp); 1176 end: 1177 vfs_op_exit(mp); 1178 vfs_unbusy(mp); 1179 VI_LOCK(vp); 1180 vp->v_iflag &= ~VI_MOUNT; 1181 VI_UNLOCK(vp); 1182 vrele(vp); 1183 return (error != 0 ? error : export_error); 1184 } 1185 1186 /* 1187 * vfs_domount(): actually attempt a filesystem mount. 1188 */ 1189 static int 1190 vfs_domount( 1191 struct thread *td, /* Calling thread. */ 1192 const char *fstype, /* Filesystem type. */ 1193 char *fspath, /* Mount path. */ 1194 uint64_t fsflags, /* Flags common to all filesystems. */ 1195 struct vfsoptlist **optlist /* Options local to the filesystem. */ 1196 ) 1197 { 1198 struct vfsconf *vfsp; 1199 struct nameidata nd; 1200 struct vnode *vp; 1201 char *pathbuf; 1202 int error; 1203 1204 /* 1205 * Be ultra-paranoid about making sure the type and fspath 1206 * variables will fit in our mp buffers, including the 1207 * terminating NUL. 1208 */ 1209 if (strlen(fstype) >= MFSNAMELEN || strlen(fspath) >= MNAMELEN) 1210 return (ENAMETOOLONG); 1211 1212 if (jailed(td->td_ucred) || usermount == 0) { 1213 if ((error = priv_check(td, PRIV_VFS_MOUNT)) != 0) 1214 return (error); 1215 } 1216 1217 /* 1218 * Do not allow NFS export or MNT_SUIDDIR by unprivileged users. 1219 */ 1220 if (fsflags & MNT_EXPORTED) { 1221 error = priv_check(td, PRIV_VFS_MOUNT_EXPORTED); 1222 if (error) 1223 return (error); 1224 } 1225 if (fsflags & MNT_SUIDDIR) { 1226 error = priv_check(td, PRIV_VFS_MOUNT_SUIDDIR); 1227 if (error) 1228 return (error); 1229 } 1230 /* 1231 * Silently enforce MNT_NOSUID and MNT_USER for unprivileged users. 1232 */ 1233 if ((fsflags & (MNT_NOSUID | MNT_USER)) != (MNT_NOSUID | MNT_USER)) { 1234 if (priv_check(td, PRIV_VFS_MOUNT_NONUSER) != 0) 1235 fsflags |= MNT_NOSUID | MNT_USER; 1236 } 1237 1238 /* Load KLDs before we lock the covered vnode to avoid reversals. */ 1239 vfsp = NULL; 1240 if ((fsflags & MNT_UPDATE) == 0) { 1241 /* Don't try to load KLDs if we're mounting the root. */ 1242 if (fsflags & MNT_ROOTFS) 1243 vfsp = vfs_byname(fstype); 1244 else 1245 vfsp = vfs_byname_kld(fstype, td, &error); 1246 if (vfsp == NULL) 1247 return (ENODEV); 1248 } 1249 1250 /* 1251 * Get vnode to be covered or mount point's vnode in case of MNT_UPDATE. 1252 */ 1253 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, 1254 UIO_SYSSPACE, fspath, td); 1255 error = namei(&nd); 1256 if (error != 0) 1257 return (error); 1258 NDFREE(&nd, NDF_ONLY_PNBUF); 1259 vp = nd.ni_vp; 1260 if ((fsflags & MNT_UPDATE) == 0) { 1261 if ((vp->v_vflag & VV_ROOT) != 0 && 1262 (fsflags & MNT_NOCOVER) != 0) { 1263 vput(vp); 1264 return (EBUSY); 1265 } 1266 pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK); 1267 strcpy(pathbuf, fspath); 1268 error = vn_path_to_global_path(td, vp, pathbuf, MNAMELEN); 1269 /* debug.disablefullpath == 1 results in ENODEV */ 1270 if (error == 0 || error == ENODEV) { 1271 error = vfs_domount_first(td, vfsp, pathbuf, vp, 1272 fsflags, optlist); 1273 } 1274 free(pathbuf, M_TEMP); 1275 } else 1276 error = vfs_domount_update(td, vp, fsflags, optlist); 1277 1278 return (error); 1279 } 1280 1281 /* 1282 * Unmount a filesystem. 1283 * 1284 * Note: unmount takes a path to the vnode mounted on as argument, not 1285 * special file (as before). 1286 */ 1287 #ifndef _SYS_SYSPROTO_H_ 1288 struct unmount_args { 1289 char *path; 1290 int flags; 1291 }; 1292 #endif 1293 /* ARGSUSED */ 1294 int 1295 sys_unmount(struct thread *td, struct unmount_args *uap) 1296 { 1297 1298 return (kern_unmount(td, uap->path, uap->flags)); 1299 } 1300 1301 int 1302 kern_unmount(struct thread *td, const char *path, int flags) 1303 { 1304 struct nameidata nd; 1305 struct mount *mp; 1306 char *pathbuf; 1307 int error, id0, id1; 1308 1309 AUDIT_ARG_VALUE(flags); 1310 if (jailed(td->td_ucred) || usermount == 0) { 1311 error = priv_check(td, PRIV_VFS_UNMOUNT); 1312 if (error) 1313 return (error); 1314 } 1315 1316 pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK); 1317 error = copyinstr(path, pathbuf, MNAMELEN, NULL); 1318 if (error) { 1319 free(pathbuf, M_TEMP); 1320 return (error); 1321 } 1322 if (flags & MNT_BYFSID) { 1323 AUDIT_ARG_TEXT(pathbuf); 1324 /* Decode the filesystem ID. */ 1325 if (sscanf(pathbuf, "FSID:%d:%d", &id0, &id1) != 2) { 1326 free(pathbuf, M_TEMP); 1327 return (EINVAL); 1328 } 1329 1330 mtx_lock(&mountlist_mtx); 1331 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1332 if (mp->mnt_stat.f_fsid.val[0] == id0 && 1333 mp->mnt_stat.f_fsid.val[1] == id1) { 1334 vfs_ref(mp); 1335 break; 1336 } 1337 } 1338 mtx_unlock(&mountlist_mtx); 1339 } else { 1340 /* 1341 * Try to find global path for path argument. 1342 */ 1343 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, 1344 UIO_SYSSPACE, pathbuf, td); 1345 if (namei(&nd) == 0) { 1346 NDFREE(&nd, NDF_ONLY_PNBUF); 1347 error = vn_path_to_global_path(td, nd.ni_vp, pathbuf, 1348 MNAMELEN); 1349 if (error == 0 || error == ENODEV) 1350 vput(nd.ni_vp); 1351 } 1352 mtx_lock(&mountlist_mtx); 1353 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1354 if (strcmp(mp->mnt_stat.f_mntonname, pathbuf) == 0) { 1355 vfs_ref(mp); 1356 break; 1357 } 1358 } 1359 mtx_unlock(&mountlist_mtx); 1360 } 1361 free(pathbuf, M_TEMP); 1362 if (mp == NULL) { 1363 /* 1364 * Previously we returned ENOENT for a nonexistent path and 1365 * EINVAL for a non-mountpoint. We cannot tell these apart 1366 * now, so in the !MNT_BYFSID case return the more likely 1367 * EINVAL for compatibility. 1368 */ 1369 return ((flags & MNT_BYFSID) ? ENOENT : EINVAL); 1370 } 1371 1372 /* 1373 * Don't allow unmounting the root filesystem. 1374 */ 1375 if (mp->mnt_flag & MNT_ROOTFS) { 1376 vfs_rel(mp); 1377 return (EINVAL); 1378 } 1379 error = dounmount(mp, flags, td); 1380 return (error); 1381 } 1382 1383 /* 1384 * Return error if any of the vnodes, ignoring the root vnode 1385 * and the syncer vnode, have non-zero usecount. 1386 * 1387 * This function is purely advisory - it can return false positives 1388 * and negatives. 1389 */ 1390 static int 1391 vfs_check_usecounts(struct mount *mp) 1392 { 1393 struct vnode *vp, *mvp; 1394 1395 MNT_VNODE_FOREACH_ALL(vp, mp, mvp) { 1396 if ((vp->v_vflag & VV_ROOT) == 0 && vp->v_type != VNON && 1397 vp->v_usecount != 0) { 1398 VI_UNLOCK(vp); 1399 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp); 1400 return (EBUSY); 1401 } 1402 VI_UNLOCK(vp); 1403 } 1404 1405 return (0); 1406 } 1407 1408 static void 1409 dounmount_cleanup(struct mount *mp, struct vnode *coveredvp, int mntkflags) 1410 { 1411 1412 mtx_assert(MNT_MTX(mp), MA_OWNED); 1413 mp->mnt_kern_flag &= ~mntkflags; 1414 if ((mp->mnt_kern_flag & MNTK_MWAIT) != 0) { 1415 mp->mnt_kern_flag &= ~MNTK_MWAIT; 1416 wakeup(mp); 1417 } 1418 vfs_op_exit_locked(mp); 1419 MNT_IUNLOCK(mp); 1420 if (coveredvp != NULL) { 1421 VOP_UNLOCK(coveredvp); 1422 vdrop(coveredvp); 1423 } 1424 vn_finished_write(mp); 1425 } 1426 1427 /* 1428 * There are various reference counters associated with the mount point. 1429 * Normally it is permitted to modify them without taking the mnt ilock, 1430 * but this behavior can be temporarily disabled if stable value is needed 1431 * or callers are expected to block (e.g. to not allow new users during 1432 * forced unmount). 1433 */ 1434 void 1435 vfs_op_enter(struct mount *mp) 1436 { 1437 int cpu; 1438 1439 MNT_ILOCK(mp); 1440 mp->mnt_vfs_ops++; 1441 if (mp->mnt_vfs_ops > 1) { 1442 MNT_IUNLOCK(mp); 1443 return; 1444 } 1445 /* 1446 * Paired with a fence in vfs_op_thread_enter(). See the comment 1447 * above it for details. 1448 */ 1449 atomic_thread_fence_seq_cst(); 1450 vfs_op_barrier_wait(mp); 1451 /* 1452 * Paired with a fence in vfs_op_thread_exit(). 1453 */ 1454 atomic_thread_fence_acq(); 1455 CPU_FOREACH(cpu) { 1456 mp->mnt_ref += 1457 zpcpu_replace_cpu(mp->mnt_ref_pcpu, 0, cpu); 1458 mp->mnt_lockref += 1459 zpcpu_replace_cpu(mp->mnt_lockref_pcpu, 0, cpu); 1460 mp->mnt_writeopcount += 1461 zpcpu_replace_cpu(mp->mnt_writeopcount_pcpu, 0, cpu); 1462 } 1463 MNT_IUNLOCK(mp); 1464 vfs_assert_mount_counters(mp); 1465 } 1466 1467 void 1468 vfs_op_exit_locked(struct mount *mp) 1469 { 1470 1471 mtx_assert(MNT_MTX(mp), MA_OWNED); 1472 1473 if (mp->mnt_vfs_ops <= 0) 1474 panic("%s: invalid vfs_ops count %d for mp %p\n", 1475 __func__, mp->mnt_vfs_ops, mp); 1476 mp->mnt_vfs_ops--; 1477 } 1478 1479 void 1480 vfs_op_exit(struct mount *mp) 1481 { 1482 1483 MNT_ILOCK(mp); 1484 vfs_op_exit_locked(mp); 1485 MNT_IUNLOCK(mp); 1486 } 1487 1488 /* 1489 * It is assumed the caller already posted at least an acquire barrier. 1490 */ 1491 void 1492 vfs_op_barrier_wait(struct mount *mp) 1493 { 1494 int *in_op; 1495 int cpu; 1496 1497 CPU_FOREACH(cpu) { 1498 in_op = zpcpu_get_cpu(mp->mnt_thread_in_ops_pcpu, cpu); 1499 while (atomic_load_int(in_op)) 1500 cpu_spinwait(); 1501 } 1502 } 1503 1504 #ifdef DIAGNOSTIC 1505 void 1506 vfs_assert_mount_counters(struct mount *mp) 1507 { 1508 int cpu; 1509 1510 if (mp->mnt_vfs_ops == 0) 1511 return; 1512 1513 CPU_FOREACH(cpu) { 1514 if (*(int *)zpcpu_get_cpu(mp->mnt_ref_pcpu, cpu) != 0 || 1515 *(int *)zpcpu_get_cpu(mp->mnt_lockref_pcpu, cpu) != 0 || 1516 *(int *)zpcpu_get_cpu(mp->mnt_writeopcount_pcpu, cpu) != 0) 1517 vfs_dump_mount_counters(mp); 1518 } 1519 } 1520 1521 void 1522 vfs_dump_mount_counters(struct mount *mp) 1523 { 1524 int cpu, *count; 1525 int ref, lockref, writeopcount; 1526 1527 printf("%s: mp %p vfs_ops %d\n", __func__, mp, mp->mnt_vfs_ops); 1528 1529 printf(" ref : "); 1530 ref = mp->mnt_ref; 1531 CPU_FOREACH(cpu) { 1532 count = zpcpu_get_cpu(mp->mnt_ref_pcpu, cpu); 1533 printf("%d ", *count); 1534 ref += *count; 1535 } 1536 printf("\n"); 1537 printf(" lockref : "); 1538 lockref = mp->mnt_lockref; 1539 CPU_FOREACH(cpu) { 1540 count = zpcpu_get_cpu(mp->mnt_lockref_pcpu, cpu); 1541 printf("%d ", *count); 1542 lockref += *count; 1543 } 1544 printf("\n"); 1545 printf("writeopcount: "); 1546 writeopcount = mp->mnt_writeopcount; 1547 CPU_FOREACH(cpu) { 1548 count = zpcpu_get_cpu(mp->mnt_writeopcount_pcpu, cpu); 1549 printf("%d ", *count); 1550 writeopcount += *count; 1551 } 1552 printf("\n"); 1553 1554 printf("counter struct total\n"); 1555 printf("ref %-5d %-5d\n", mp->mnt_ref, ref); 1556 printf("lockref %-5d %-5d\n", mp->mnt_lockref, lockref); 1557 printf("writeopcount %-5d %-5d\n", mp->mnt_writeopcount, writeopcount); 1558 1559 panic("invalid counts on struct mount"); 1560 } 1561 #endif 1562 1563 int 1564 vfs_mount_fetch_counter(struct mount *mp, enum mount_counter which) 1565 { 1566 int *base, *pcpu; 1567 int cpu, sum; 1568 1569 switch (which) { 1570 case MNT_COUNT_REF: 1571 base = &mp->mnt_ref; 1572 pcpu = mp->mnt_ref_pcpu; 1573 break; 1574 case MNT_COUNT_LOCKREF: 1575 base = &mp->mnt_lockref; 1576 pcpu = mp->mnt_lockref_pcpu; 1577 break; 1578 case MNT_COUNT_WRITEOPCOUNT: 1579 base = &mp->mnt_writeopcount; 1580 pcpu = mp->mnt_writeopcount_pcpu; 1581 break; 1582 } 1583 1584 sum = *base; 1585 CPU_FOREACH(cpu) { 1586 sum += *(int *)zpcpu_get_cpu(pcpu, cpu); 1587 } 1588 return (sum); 1589 } 1590 1591 /* 1592 * Do the actual filesystem unmount. 1593 */ 1594 int 1595 dounmount(struct mount *mp, int flags, struct thread *td) 1596 { 1597 struct vnode *coveredvp, *rootvp; 1598 int error; 1599 uint64_t async_flag; 1600 int mnt_gen_r; 1601 1602 if ((coveredvp = mp->mnt_vnodecovered) != NULL) { 1603 mnt_gen_r = mp->mnt_gen; 1604 VI_LOCK(coveredvp); 1605 vholdl(coveredvp); 1606 vn_lock(coveredvp, LK_EXCLUSIVE | LK_INTERLOCK | LK_RETRY); 1607 /* 1608 * Check for mp being unmounted while waiting for the 1609 * covered vnode lock. 1610 */ 1611 if (coveredvp->v_mountedhere != mp || 1612 coveredvp->v_mountedhere->mnt_gen != mnt_gen_r) { 1613 VOP_UNLOCK(coveredvp); 1614 vdrop(coveredvp); 1615 vfs_rel(mp); 1616 return (EBUSY); 1617 } 1618 } 1619 1620 /* 1621 * Only privileged root, or (if MNT_USER is set) the user that did the 1622 * original mount is permitted to unmount this filesystem. 1623 */ 1624 error = vfs_suser(mp, td); 1625 if (error != 0) { 1626 if (coveredvp != NULL) { 1627 VOP_UNLOCK(coveredvp); 1628 vdrop(coveredvp); 1629 } 1630 vfs_rel(mp); 1631 return (error); 1632 } 1633 1634 vfs_op_enter(mp); 1635 1636 vn_start_write(NULL, &mp, V_WAIT | V_MNTREF); 1637 MNT_ILOCK(mp); 1638 if ((mp->mnt_kern_flag & MNTK_UNMOUNT) != 0 || 1639 (mp->mnt_flag & MNT_UPDATE) != 0 || 1640 !TAILQ_EMPTY(&mp->mnt_uppers)) { 1641 dounmount_cleanup(mp, coveredvp, 0); 1642 return (EBUSY); 1643 } 1644 mp->mnt_kern_flag |= MNTK_UNMOUNT; 1645 rootvp = vfs_cache_root_clear(mp); 1646 if (flags & MNT_NONBUSY) { 1647 MNT_IUNLOCK(mp); 1648 error = vfs_check_usecounts(mp); 1649 MNT_ILOCK(mp); 1650 if (error != 0) { 1651 dounmount_cleanup(mp, coveredvp, MNTK_UNMOUNT); 1652 if (rootvp != NULL) 1653 vrele(rootvp); 1654 return (error); 1655 } 1656 } 1657 /* Allow filesystems to detect that a forced unmount is in progress. */ 1658 if (flags & MNT_FORCE) { 1659 mp->mnt_kern_flag |= MNTK_UNMOUNTF; 1660 MNT_IUNLOCK(mp); 1661 /* 1662 * Must be done after setting MNTK_UNMOUNTF and before 1663 * waiting for mnt_lockref to become 0. 1664 */ 1665 VFS_PURGE(mp); 1666 MNT_ILOCK(mp); 1667 } 1668 error = 0; 1669 if (mp->mnt_lockref) { 1670 mp->mnt_kern_flag |= MNTK_DRAINING; 1671 error = msleep(&mp->mnt_lockref, MNT_MTX(mp), PVFS, 1672 "mount drain", 0); 1673 } 1674 MNT_IUNLOCK(mp); 1675 KASSERT(mp->mnt_lockref == 0, 1676 ("%s: invalid lock refcount in the drain path @ %s:%d", 1677 __func__, __FILE__, __LINE__)); 1678 KASSERT(error == 0, 1679 ("%s: invalid return value for msleep in the drain path @ %s:%d", 1680 __func__, __FILE__, __LINE__)); 1681 1682 if (rootvp != NULL) 1683 vrele(rootvp); 1684 1685 if (mp->mnt_flag & MNT_EXPUBLIC) 1686 vfs_setpublicfs(NULL, NULL, NULL); 1687 1688 /* 1689 * From now, we can claim that the use reference on the 1690 * coveredvp is ours, and the ref can be released only by 1691 * successfull unmount by us, or left for later unmount 1692 * attempt. The previously acquired hold reference is no 1693 * longer needed to protect the vnode from reuse. 1694 */ 1695 if (coveredvp != NULL) 1696 vdrop(coveredvp); 1697 1698 vfs_periodic(mp, MNT_WAIT); 1699 MNT_ILOCK(mp); 1700 async_flag = mp->mnt_flag & MNT_ASYNC; 1701 mp->mnt_flag &= ~MNT_ASYNC; 1702 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1703 MNT_IUNLOCK(mp); 1704 cache_purgevfs(mp, false); /* remove cache entries for this file sys */ 1705 vfs_deallocate_syncvnode(mp); 1706 error = VFS_UNMOUNT(mp, flags); 1707 vn_finished_write(mp); 1708 /* 1709 * If we failed to flush the dirty blocks for this mount point, 1710 * undo all the cdir/rdir and rootvnode changes we made above. 1711 * Unless we failed to do so because the device is reporting that 1712 * it doesn't exist anymore. 1713 */ 1714 if (error && error != ENXIO) { 1715 MNT_ILOCK(mp); 1716 if ((mp->mnt_flag & MNT_RDONLY) == 0) { 1717 MNT_IUNLOCK(mp); 1718 vfs_allocate_syncvnode(mp); 1719 MNT_ILOCK(mp); 1720 } 1721 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 1722 mp->mnt_flag |= async_flag; 1723 if ((mp->mnt_flag & MNT_ASYNC) != 0 && 1724 (mp->mnt_kern_flag & MNTK_NOASYNC) == 0) 1725 mp->mnt_kern_flag |= MNTK_ASYNC; 1726 if (mp->mnt_kern_flag & MNTK_MWAIT) { 1727 mp->mnt_kern_flag &= ~MNTK_MWAIT; 1728 wakeup(mp); 1729 } 1730 vfs_op_exit_locked(mp); 1731 MNT_IUNLOCK(mp); 1732 if (coveredvp) 1733 VOP_UNLOCK(coveredvp); 1734 return (error); 1735 } 1736 mtx_lock(&mountlist_mtx); 1737 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1738 mtx_unlock(&mountlist_mtx); 1739 EVENTHANDLER_DIRECT_INVOKE(vfs_unmounted, mp, td); 1740 if (coveredvp != NULL) { 1741 coveredvp->v_mountedhere = NULL; 1742 VOP_UNLOCK(coveredvp); 1743 } 1744 vfs_event_signal(NULL, VQ_UNMOUNT, 0); 1745 if (rootvnode != NULL && mp == rootvnode->v_mount) { 1746 vrele(rootvnode); 1747 rootvnode = NULL; 1748 } 1749 if (mp == rootdevmp) 1750 rootdevmp = NULL; 1751 vfs_mount_destroy(mp); 1752 return (0); 1753 } 1754 1755 /* 1756 * Report errors during filesystem mounting. 1757 */ 1758 void 1759 vfs_mount_error(struct mount *mp, const char *fmt, ...) 1760 { 1761 struct vfsoptlist *moptlist = mp->mnt_optnew; 1762 va_list ap; 1763 int error, len; 1764 char *errmsg; 1765 1766 error = vfs_getopt(moptlist, "errmsg", (void **)&errmsg, &len); 1767 if (error || errmsg == NULL || len <= 0) 1768 return; 1769 1770 va_start(ap, fmt); 1771 vsnprintf(errmsg, (size_t)len, fmt, ap); 1772 va_end(ap); 1773 } 1774 1775 void 1776 vfs_opterror(struct vfsoptlist *opts, const char *fmt, ...) 1777 { 1778 va_list ap; 1779 int error, len; 1780 char *errmsg; 1781 1782 error = vfs_getopt(opts, "errmsg", (void **)&errmsg, &len); 1783 if (error || errmsg == NULL || len <= 0) 1784 return; 1785 1786 va_start(ap, fmt); 1787 vsnprintf(errmsg, (size_t)len, fmt, ap); 1788 va_end(ap); 1789 } 1790 1791 /* 1792 * --------------------------------------------------------------------- 1793 * Functions for querying mount options/arguments from filesystems. 1794 */ 1795 1796 /* 1797 * Check that no unknown options are given 1798 */ 1799 int 1800 vfs_filteropt(struct vfsoptlist *opts, const char **legal) 1801 { 1802 struct vfsopt *opt; 1803 char errmsg[255]; 1804 const char **t, *p, *q; 1805 int ret = 0; 1806 1807 TAILQ_FOREACH(opt, opts, link) { 1808 p = opt->name; 1809 q = NULL; 1810 if (p[0] == 'n' && p[1] == 'o') 1811 q = p + 2; 1812 for(t = global_opts; *t != NULL; t++) { 1813 if (strcmp(*t, p) == 0) 1814 break; 1815 if (q != NULL) { 1816 if (strcmp(*t, q) == 0) 1817 break; 1818 } 1819 } 1820 if (*t != NULL) 1821 continue; 1822 for(t = legal; *t != NULL; t++) { 1823 if (strcmp(*t, p) == 0) 1824 break; 1825 if (q != NULL) { 1826 if (strcmp(*t, q) == 0) 1827 break; 1828 } 1829 } 1830 if (*t != NULL) 1831 continue; 1832 snprintf(errmsg, sizeof(errmsg), 1833 "mount option <%s> is unknown", p); 1834 ret = EINVAL; 1835 } 1836 if (ret != 0) { 1837 TAILQ_FOREACH(opt, opts, link) { 1838 if (strcmp(opt->name, "errmsg") == 0) { 1839 strncpy((char *)opt->value, errmsg, opt->len); 1840 break; 1841 } 1842 } 1843 if (opt == NULL) 1844 printf("%s\n", errmsg); 1845 } 1846 return (ret); 1847 } 1848 1849 /* 1850 * Get a mount option by its name. 1851 * 1852 * Return 0 if the option was found, ENOENT otherwise. 1853 * If len is non-NULL it will be filled with the length 1854 * of the option. If buf is non-NULL, it will be filled 1855 * with the address of the option. 1856 */ 1857 int 1858 vfs_getopt(struct vfsoptlist *opts, const char *name, void **buf, int *len) 1859 { 1860 struct vfsopt *opt; 1861 1862 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1863 1864 TAILQ_FOREACH(opt, opts, link) { 1865 if (strcmp(name, opt->name) == 0) { 1866 opt->seen = 1; 1867 if (len != NULL) 1868 *len = opt->len; 1869 if (buf != NULL) 1870 *buf = opt->value; 1871 return (0); 1872 } 1873 } 1874 return (ENOENT); 1875 } 1876 1877 int 1878 vfs_getopt_pos(struct vfsoptlist *opts, const char *name) 1879 { 1880 struct vfsopt *opt; 1881 1882 if (opts == NULL) 1883 return (-1); 1884 1885 TAILQ_FOREACH(opt, opts, link) { 1886 if (strcmp(name, opt->name) == 0) { 1887 opt->seen = 1; 1888 return (opt->pos); 1889 } 1890 } 1891 return (-1); 1892 } 1893 1894 int 1895 vfs_getopt_size(struct vfsoptlist *opts, const char *name, off_t *value) 1896 { 1897 char *opt_value, *vtp; 1898 quad_t iv; 1899 int error, opt_len; 1900 1901 error = vfs_getopt(opts, name, (void **)&opt_value, &opt_len); 1902 if (error != 0) 1903 return (error); 1904 if (opt_len == 0 || opt_value == NULL) 1905 return (EINVAL); 1906 if (opt_value[0] == '\0' || opt_value[opt_len - 1] != '\0') 1907 return (EINVAL); 1908 iv = strtoq(opt_value, &vtp, 0); 1909 if (vtp == opt_value || (vtp[0] != '\0' && vtp[1] != '\0')) 1910 return (EINVAL); 1911 if (iv < 0) 1912 return (EINVAL); 1913 switch (vtp[0]) { 1914 case 't': case 'T': 1915 iv *= 1024; 1916 /* FALLTHROUGH */ 1917 case 'g': case 'G': 1918 iv *= 1024; 1919 /* FALLTHROUGH */ 1920 case 'm': case 'M': 1921 iv *= 1024; 1922 /* FALLTHROUGH */ 1923 case 'k': case 'K': 1924 iv *= 1024; 1925 case '\0': 1926 break; 1927 default: 1928 return (EINVAL); 1929 } 1930 *value = iv; 1931 1932 return (0); 1933 } 1934 1935 char * 1936 vfs_getopts(struct vfsoptlist *opts, const char *name, int *error) 1937 { 1938 struct vfsopt *opt; 1939 1940 *error = 0; 1941 TAILQ_FOREACH(opt, opts, link) { 1942 if (strcmp(name, opt->name) != 0) 1943 continue; 1944 opt->seen = 1; 1945 if (opt->len == 0 || 1946 ((char *)opt->value)[opt->len - 1] != '\0') { 1947 *error = EINVAL; 1948 return (NULL); 1949 } 1950 return (opt->value); 1951 } 1952 *error = ENOENT; 1953 return (NULL); 1954 } 1955 1956 int 1957 vfs_flagopt(struct vfsoptlist *opts, const char *name, uint64_t *w, 1958 uint64_t val) 1959 { 1960 struct vfsopt *opt; 1961 1962 TAILQ_FOREACH(opt, opts, link) { 1963 if (strcmp(name, opt->name) == 0) { 1964 opt->seen = 1; 1965 if (w != NULL) 1966 *w |= val; 1967 return (1); 1968 } 1969 } 1970 if (w != NULL) 1971 *w &= ~val; 1972 return (0); 1973 } 1974 1975 int 1976 vfs_scanopt(struct vfsoptlist *opts, const char *name, const char *fmt, ...) 1977 { 1978 va_list ap; 1979 struct vfsopt *opt; 1980 int ret; 1981 1982 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1983 1984 TAILQ_FOREACH(opt, opts, link) { 1985 if (strcmp(name, opt->name) != 0) 1986 continue; 1987 opt->seen = 1; 1988 if (opt->len == 0 || opt->value == NULL) 1989 return (0); 1990 if (((char *)opt->value)[opt->len - 1] != '\0') 1991 return (0); 1992 va_start(ap, fmt); 1993 ret = vsscanf(opt->value, fmt, ap); 1994 va_end(ap); 1995 return (ret); 1996 } 1997 return (0); 1998 } 1999 2000 int 2001 vfs_setopt(struct vfsoptlist *opts, const char *name, void *value, int len) 2002 { 2003 struct vfsopt *opt; 2004 2005 TAILQ_FOREACH(opt, opts, link) { 2006 if (strcmp(name, opt->name) != 0) 2007 continue; 2008 opt->seen = 1; 2009 if (opt->value == NULL) 2010 opt->len = len; 2011 else { 2012 if (opt->len != len) 2013 return (EINVAL); 2014 bcopy(value, opt->value, len); 2015 } 2016 return (0); 2017 } 2018 return (ENOENT); 2019 } 2020 2021 int 2022 vfs_setopt_part(struct vfsoptlist *opts, const char *name, void *value, int len) 2023 { 2024 struct vfsopt *opt; 2025 2026 TAILQ_FOREACH(opt, opts, link) { 2027 if (strcmp(name, opt->name) != 0) 2028 continue; 2029 opt->seen = 1; 2030 if (opt->value == NULL) 2031 opt->len = len; 2032 else { 2033 if (opt->len < len) 2034 return (EINVAL); 2035 opt->len = len; 2036 bcopy(value, opt->value, len); 2037 } 2038 return (0); 2039 } 2040 return (ENOENT); 2041 } 2042 2043 int 2044 vfs_setopts(struct vfsoptlist *opts, const char *name, const char *value) 2045 { 2046 struct vfsopt *opt; 2047 2048 TAILQ_FOREACH(opt, opts, link) { 2049 if (strcmp(name, opt->name) != 0) 2050 continue; 2051 opt->seen = 1; 2052 if (opt->value == NULL) 2053 opt->len = strlen(value) + 1; 2054 else if (strlcpy(opt->value, value, opt->len) >= opt->len) 2055 return (EINVAL); 2056 return (0); 2057 } 2058 return (ENOENT); 2059 } 2060 2061 /* 2062 * Find and copy a mount option. 2063 * 2064 * The size of the buffer has to be specified 2065 * in len, if it is not the same length as the 2066 * mount option, EINVAL is returned. 2067 * Returns ENOENT if the option is not found. 2068 */ 2069 int 2070 vfs_copyopt(struct vfsoptlist *opts, const char *name, void *dest, int len) 2071 { 2072 struct vfsopt *opt; 2073 2074 KASSERT(opts != NULL, ("vfs_copyopt: caller passed 'opts' as NULL")); 2075 2076 TAILQ_FOREACH(opt, opts, link) { 2077 if (strcmp(name, opt->name) == 0) { 2078 opt->seen = 1; 2079 if (len != opt->len) 2080 return (EINVAL); 2081 bcopy(opt->value, dest, opt->len); 2082 return (0); 2083 } 2084 } 2085 return (ENOENT); 2086 } 2087 2088 int 2089 __vfs_statfs(struct mount *mp, struct statfs *sbp) 2090 { 2091 2092 /* 2093 * Filesystems only fill in part of the structure for updates, we 2094 * have to read the entirety first to get all content. 2095 */ 2096 memcpy(sbp, &mp->mnt_stat, sizeof(*sbp)); 2097 2098 /* 2099 * Set these in case the underlying filesystem fails to do so. 2100 */ 2101 sbp->f_version = STATFS_VERSION; 2102 sbp->f_namemax = NAME_MAX; 2103 sbp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK; 2104 2105 return (mp->mnt_op->vfs_statfs(mp, sbp)); 2106 } 2107 2108 void 2109 vfs_mountedfrom(struct mount *mp, const char *from) 2110 { 2111 2112 bzero(mp->mnt_stat.f_mntfromname, sizeof mp->mnt_stat.f_mntfromname); 2113 strlcpy(mp->mnt_stat.f_mntfromname, from, 2114 sizeof mp->mnt_stat.f_mntfromname); 2115 } 2116 2117 /* 2118 * --------------------------------------------------------------------- 2119 * This is the api for building mount args and mounting filesystems from 2120 * inside the kernel. 2121 * 2122 * The API works by accumulation of individual args. First error is 2123 * latched. 2124 * 2125 * XXX: should be documented in new manpage kernel_mount(9) 2126 */ 2127 2128 /* A memory allocation which must be freed when we are done */ 2129 struct mntaarg { 2130 SLIST_ENTRY(mntaarg) next; 2131 }; 2132 2133 /* The header for the mount arguments */ 2134 struct mntarg { 2135 struct iovec *v; 2136 int len; 2137 int error; 2138 SLIST_HEAD(, mntaarg) list; 2139 }; 2140 2141 /* 2142 * Add a boolean argument. 2143 * 2144 * flag is the boolean value. 2145 * name must start with "no". 2146 */ 2147 struct mntarg * 2148 mount_argb(struct mntarg *ma, int flag, const char *name) 2149 { 2150 2151 KASSERT(name[0] == 'n' && name[1] == 'o', 2152 ("mount_argb(...,%s): name must start with 'no'", name)); 2153 2154 return (mount_arg(ma, name + (flag ? 2 : 0), NULL, 0)); 2155 } 2156 2157 /* 2158 * Add an argument printf style 2159 */ 2160 struct mntarg * 2161 mount_argf(struct mntarg *ma, const char *name, const char *fmt, ...) 2162 { 2163 va_list ap; 2164 struct mntaarg *maa; 2165 struct sbuf *sb; 2166 int len; 2167 2168 if (ma == NULL) { 2169 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2170 SLIST_INIT(&ma->list); 2171 } 2172 if (ma->error) 2173 return (ma); 2174 2175 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 2176 M_MOUNT, M_WAITOK); 2177 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 2178 ma->v[ma->len].iov_len = strlen(name) + 1; 2179 ma->len++; 2180 2181 sb = sbuf_new_auto(); 2182 va_start(ap, fmt); 2183 sbuf_vprintf(sb, fmt, ap); 2184 va_end(ap); 2185 sbuf_finish(sb); 2186 len = sbuf_len(sb) + 1; 2187 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 2188 SLIST_INSERT_HEAD(&ma->list, maa, next); 2189 bcopy(sbuf_data(sb), maa + 1, len); 2190 sbuf_delete(sb); 2191 2192 ma->v[ma->len].iov_base = maa + 1; 2193 ma->v[ma->len].iov_len = len; 2194 ma->len++; 2195 2196 return (ma); 2197 } 2198 2199 /* 2200 * Add an argument which is a userland string. 2201 */ 2202 struct mntarg * 2203 mount_argsu(struct mntarg *ma, const char *name, const void *val, int len) 2204 { 2205 struct mntaarg *maa; 2206 char *tbuf; 2207 2208 if (val == NULL) 2209 return (ma); 2210 if (ma == NULL) { 2211 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2212 SLIST_INIT(&ma->list); 2213 } 2214 if (ma->error) 2215 return (ma); 2216 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 2217 SLIST_INSERT_HEAD(&ma->list, maa, next); 2218 tbuf = (void *)(maa + 1); 2219 ma->error = copyinstr(val, tbuf, len, NULL); 2220 return (mount_arg(ma, name, tbuf, -1)); 2221 } 2222 2223 /* 2224 * Plain argument. 2225 * 2226 * If length is -1, treat value as a C string. 2227 */ 2228 struct mntarg * 2229 mount_arg(struct mntarg *ma, const char *name, const void *val, int len) 2230 { 2231 2232 if (ma == NULL) { 2233 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2234 SLIST_INIT(&ma->list); 2235 } 2236 if (ma->error) 2237 return (ma); 2238 2239 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 2240 M_MOUNT, M_WAITOK); 2241 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 2242 ma->v[ma->len].iov_len = strlen(name) + 1; 2243 ma->len++; 2244 2245 ma->v[ma->len].iov_base = (void *)(uintptr_t)val; 2246 if (len < 0) 2247 ma->v[ma->len].iov_len = strlen(val) + 1; 2248 else 2249 ma->v[ma->len].iov_len = len; 2250 ma->len++; 2251 return (ma); 2252 } 2253 2254 /* 2255 * Free a mntarg structure 2256 */ 2257 static void 2258 free_mntarg(struct mntarg *ma) 2259 { 2260 struct mntaarg *maa; 2261 2262 while (!SLIST_EMPTY(&ma->list)) { 2263 maa = SLIST_FIRST(&ma->list); 2264 SLIST_REMOVE_HEAD(&ma->list, next); 2265 free(maa, M_MOUNT); 2266 } 2267 free(ma->v, M_MOUNT); 2268 free(ma, M_MOUNT); 2269 } 2270 2271 /* 2272 * Mount a filesystem 2273 */ 2274 int 2275 kernel_mount(struct mntarg *ma, uint64_t flags) 2276 { 2277 struct uio auio; 2278 int error; 2279 2280 KASSERT(ma != NULL, ("kernel_mount NULL ma")); 2281 KASSERT(ma->v != NULL, ("kernel_mount NULL ma->v")); 2282 KASSERT(!(ma->len & 1), ("kernel_mount odd ma->len (%d)", ma->len)); 2283 2284 auio.uio_iov = ma->v; 2285 auio.uio_iovcnt = ma->len; 2286 auio.uio_segflg = UIO_SYSSPACE; 2287 2288 error = ma->error; 2289 if (!error) 2290 error = vfs_donmount(curthread, flags, &auio); 2291 free_mntarg(ma); 2292 return (error); 2293 } 2294 2295 /* 2296 * A printflike function to mount a filesystem. 2297 */ 2298 int 2299 kernel_vmount(int flags, ...) 2300 { 2301 struct mntarg *ma = NULL; 2302 va_list ap; 2303 const char *cp; 2304 const void *vp; 2305 int error; 2306 2307 va_start(ap, flags); 2308 for (;;) { 2309 cp = va_arg(ap, const char *); 2310 if (cp == NULL) 2311 break; 2312 vp = va_arg(ap, const void *); 2313 ma = mount_arg(ma, cp, vp, (vp != NULL ? -1 : 0)); 2314 } 2315 va_end(ap); 2316 2317 error = kernel_mount(ma, flags); 2318 return (error); 2319 } 2320 2321 void 2322 vfs_oexport_conv(const struct oexport_args *oexp, struct export_args *exp) 2323 { 2324 2325 bcopy(oexp, exp, sizeof(*oexp)); 2326 exp->ex_numsecflavors = 0; 2327 } 2328