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 struct nameidata nd; 1298 struct mount *mp; 1299 char *pathbuf; 1300 int error, id0, id1; 1301 1302 AUDIT_ARG_VALUE(uap->flags); 1303 if (jailed(td->td_ucred) || usermount == 0) { 1304 error = priv_check(td, PRIV_VFS_UNMOUNT); 1305 if (error) 1306 return (error); 1307 } 1308 1309 pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK); 1310 error = copyinstr(uap->path, pathbuf, MNAMELEN, NULL); 1311 if (error) { 1312 free(pathbuf, M_TEMP); 1313 return (error); 1314 } 1315 if (uap->flags & MNT_BYFSID) { 1316 AUDIT_ARG_TEXT(pathbuf); 1317 /* Decode the filesystem ID. */ 1318 if (sscanf(pathbuf, "FSID:%d:%d", &id0, &id1) != 2) { 1319 free(pathbuf, M_TEMP); 1320 return (EINVAL); 1321 } 1322 1323 mtx_lock(&mountlist_mtx); 1324 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1325 if (mp->mnt_stat.f_fsid.val[0] == id0 && 1326 mp->mnt_stat.f_fsid.val[1] == id1) { 1327 vfs_ref(mp); 1328 break; 1329 } 1330 } 1331 mtx_unlock(&mountlist_mtx); 1332 } else { 1333 /* 1334 * Try to find global path for path argument. 1335 */ 1336 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, 1337 UIO_SYSSPACE, pathbuf, td); 1338 if (namei(&nd) == 0) { 1339 NDFREE(&nd, NDF_ONLY_PNBUF); 1340 error = vn_path_to_global_path(td, nd.ni_vp, pathbuf, 1341 MNAMELEN); 1342 if (error == 0 || error == ENODEV) 1343 vput(nd.ni_vp); 1344 } 1345 mtx_lock(&mountlist_mtx); 1346 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1347 if (strcmp(mp->mnt_stat.f_mntonname, pathbuf) == 0) { 1348 vfs_ref(mp); 1349 break; 1350 } 1351 } 1352 mtx_unlock(&mountlist_mtx); 1353 } 1354 free(pathbuf, M_TEMP); 1355 if (mp == NULL) { 1356 /* 1357 * Previously we returned ENOENT for a nonexistent path and 1358 * EINVAL for a non-mountpoint. We cannot tell these apart 1359 * now, so in the !MNT_BYFSID case return the more likely 1360 * EINVAL for compatibility. 1361 */ 1362 return ((uap->flags & MNT_BYFSID) ? ENOENT : EINVAL); 1363 } 1364 1365 /* 1366 * Don't allow unmounting the root filesystem. 1367 */ 1368 if (mp->mnt_flag & MNT_ROOTFS) { 1369 vfs_rel(mp); 1370 return (EINVAL); 1371 } 1372 error = dounmount(mp, uap->flags, td); 1373 return (error); 1374 } 1375 1376 /* 1377 * Return error if any of the vnodes, ignoring the root vnode 1378 * and the syncer vnode, have non-zero usecount. 1379 * 1380 * This function is purely advisory - it can return false positives 1381 * and negatives. 1382 */ 1383 static int 1384 vfs_check_usecounts(struct mount *mp) 1385 { 1386 struct vnode *vp, *mvp; 1387 1388 MNT_VNODE_FOREACH_ALL(vp, mp, mvp) { 1389 if ((vp->v_vflag & VV_ROOT) == 0 && vp->v_type != VNON && 1390 vp->v_usecount != 0) { 1391 VI_UNLOCK(vp); 1392 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp); 1393 return (EBUSY); 1394 } 1395 VI_UNLOCK(vp); 1396 } 1397 1398 return (0); 1399 } 1400 1401 static void 1402 dounmount_cleanup(struct mount *mp, struct vnode *coveredvp, int mntkflags) 1403 { 1404 1405 mtx_assert(MNT_MTX(mp), MA_OWNED); 1406 mp->mnt_kern_flag &= ~mntkflags; 1407 if ((mp->mnt_kern_flag & MNTK_MWAIT) != 0) { 1408 mp->mnt_kern_flag &= ~MNTK_MWAIT; 1409 wakeup(mp); 1410 } 1411 vfs_op_exit_locked(mp); 1412 MNT_IUNLOCK(mp); 1413 if (coveredvp != NULL) { 1414 VOP_UNLOCK(coveredvp); 1415 vdrop(coveredvp); 1416 } 1417 vn_finished_write(mp); 1418 } 1419 1420 /* 1421 * There are various reference counters associated with the mount point. 1422 * Normally it is permitted to modify them without taking the mnt ilock, 1423 * but this behavior can be temporarily disabled if stable value is needed 1424 * or callers are expected to block (e.g. to not allow new users during 1425 * forced unmount). 1426 */ 1427 void 1428 vfs_op_enter(struct mount *mp) 1429 { 1430 int cpu; 1431 1432 MNT_ILOCK(mp); 1433 mp->mnt_vfs_ops++; 1434 if (mp->mnt_vfs_ops > 1) { 1435 MNT_IUNLOCK(mp); 1436 return; 1437 } 1438 /* 1439 * Paired with a fence in vfs_op_thread_enter(). See the comment 1440 * above it for details. 1441 */ 1442 atomic_thread_fence_seq_cst(); 1443 vfs_op_barrier_wait(mp); 1444 /* 1445 * Paired with a fence in vfs_op_thread_exit(). 1446 */ 1447 atomic_thread_fence_acq(); 1448 CPU_FOREACH(cpu) { 1449 mp->mnt_ref += 1450 zpcpu_replace_cpu(mp->mnt_ref_pcpu, 0, cpu); 1451 mp->mnt_lockref += 1452 zpcpu_replace_cpu(mp->mnt_lockref_pcpu, 0, cpu); 1453 mp->mnt_writeopcount += 1454 zpcpu_replace_cpu(mp->mnt_writeopcount_pcpu, 0, cpu); 1455 } 1456 MNT_IUNLOCK(mp); 1457 vfs_assert_mount_counters(mp); 1458 } 1459 1460 void 1461 vfs_op_exit_locked(struct mount *mp) 1462 { 1463 1464 mtx_assert(MNT_MTX(mp), MA_OWNED); 1465 1466 if (mp->mnt_vfs_ops <= 0) 1467 panic("%s: invalid vfs_ops count %d for mp %p\n", 1468 __func__, mp->mnt_vfs_ops, mp); 1469 mp->mnt_vfs_ops--; 1470 } 1471 1472 void 1473 vfs_op_exit(struct mount *mp) 1474 { 1475 1476 MNT_ILOCK(mp); 1477 vfs_op_exit_locked(mp); 1478 MNT_IUNLOCK(mp); 1479 } 1480 1481 /* 1482 * It is assumed the caller already posted at least an acquire barrier. 1483 */ 1484 void 1485 vfs_op_barrier_wait(struct mount *mp) 1486 { 1487 int *in_op; 1488 int cpu; 1489 1490 CPU_FOREACH(cpu) { 1491 in_op = zpcpu_get_cpu(mp->mnt_thread_in_ops_pcpu, cpu); 1492 while (atomic_load_int(in_op)) 1493 cpu_spinwait(); 1494 } 1495 } 1496 1497 #ifdef DIAGNOSTIC 1498 void 1499 vfs_assert_mount_counters(struct mount *mp) 1500 { 1501 int cpu; 1502 1503 if (mp->mnt_vfs_ops == 0) 1504 return; 1505 1506 CPU_FOREACH(cpu) { 1507 if (*(int *)zpcpu_get_cpu(mp->mnt_ref_pcpu, cpu) != 0 || 1508 *(int *)zpcpu_get_cpu(mp->mnt_lockref_pcpu, cpu) != 0 || 1509 *(int *)zpcpu_get_cpu(mp->mnt_writeopcount_pcpu, cpu) != 0) 1510 vfs_dump_mount_counters(mp); 1511 } 1512 } 1513 1514 void 1515 vfs_dump_mount_counters(struct mount *mp) 1516 { 1517 int cpu, *count; 1518 int ref, lockref, writeopcount; 1519 1520 printf("%s: mp %p vfs_ops %d\n", __func__, mp, mp->mnt_vfs_ops); 1521 1522 printf(" ref : "); 1523 ref = mp->mnt_ref; 1524 CPU_FOREACH(cpu) { 1525 count = zpcpu_get_cpu(mp->mnt_ref_pcpu, cpu); 1526 printf("%d ", *count); 1527 ref += *count; 1528 } 1529 printf("\n"); 1530 printf(" lockref : "); 1531 lockref = mp->mnt_lockref; 1532 CPU_FOREACH(cpu) { 1533 count = zpcpu_get_cpu(mp->mnt_lockref_pcpu, cpu); 1534 printf("%d ", *count); 1535 lockref += *count; 1536 } 1537 printf("\n"); 1538 printf("writeopcount: "); 1539 writeopcount = mp->mnt_writeopcount; 1540 CPU_FOREACH(cpu) { 1541 count = zpcpu_get_cpu(mp->mnt_writeopcount_pcpu, cpu); 1542 printf("%d ", *count); 1543 writeopcount += *count; 1544 } 1545 printf("\n"); 1546 1547 printf("counter struct total\n"); 1548 printf("ref %-5d %-5d\n", mp->mnt_ref, ref); 1549 printf("lockref %-5d %-5d\n", mp->mnt_lockref, lockref); 1550 printf("writeopcount %-5d %-5d\n", mp->mnt_writeopcount, writeopcount); 1551 1552 panic("invalid counts on struct mount"); 1553 } 1554 #endif 1555 1556 int 1557 vfs_mount_fetch_counter(struct mount *mp, enum mount_counter which) 1558 { 1559 int *base, *pcpu; 1560 int cpu, sum; 1561 1562 switch (which) { 1563 case MNT_COUNT_REF: 1564 base = &mp->mnt_ref; 1565 pcpu = mp->mnt_ref_pcpu; 1566 break; 1567 case MNT_COUNT_LOCKREF: 1568 base = &mp->mnt_lockref; 1569 pcpu = mp->mnt_lockref_pcpu; 1570 break; 1571 case MNT_COUNT_WRITEOPCOUNT: 1572 base = &mp->mnt_writeopcount; 1573 pcpu = mp->mnt_writeopcount_pcpu; 1574 break; 1575 } 1576 1577 sum = *base; 1578 CPU_FOREACH(cpu) { 1579 sum += *(int *)zpcpu_get_cpu(pcpu, cpu); 1580 } 1581 return (sum); 1582 } 1583 1584 /* 1585 * Do the actual filesystem unmount. 1586 */ 1587 int 1588 dounmount(struct mount *mp, int flags, struct thread *td) 1589 { 1590 struct vnode *coveredvp, *rootvp; 1591 int error; 1592 uint64_t async_flag; 1593 int mnt_gen_r; 1594 1595 if ((coveredvp = mp->mnt_vnodecovered) != NULL) { 1596 mnt_gen_r = mp->mnt_gen; 1597 VI_LOCK(coveredvp); 1598 vholdl(coveredvp); 1599 vn_lock(coveredvp, LK_EXCLUSIVE | LK_INTERLOCK | LK_RETRY); 1600 /* 1601 * Check for mp being unmounted while waiting for the 1602 * covered vnode lock. 1603 */ 1604 if (coveredvp->v_mountedhere != mp || 1605 coveredvp->v_mountedhere->mnt_gen != mnt_gen_r) { 1606 VOP_UNLOCK(coveredvp); 1607 vdrop(coveredvp); 1608 vfs_rel(mp); 1609 return (EBUSY); 1610 } 1611 } 1612 1613 /* 1614 * Only privileged root, or (if MNT_USER is set) the user that did the 1615 * original mount is permitted to unmount this filesystem. 1616 */ 1617 error = vfs_suser(mp, td); 1618 if (error != 0) { 1619 if (coveredvp != NULL) { 1620 VOP_UNLOCK(coveredvp); 1621 vdrop(coveredvp); 1622 } 1623 vfs_rel(mp); 1624 return (error); 1625 } 1626 1627 vfs_op_enter(mp); 1628 1629 vn_start_write(NULL, &mp, V_WAIT | V_MNTREF); 1630 MNT_ILOCK(mp); 1631 if ((mp->mnt_kern_flag & MNTK_UNMOUNT) != 0 || 1632 (mp->mnt_flag & MNT_UPDATE) != 0 || 1633 !TAILQ_EMPTY(&mp->mnt_uppers)) { 1634 dounmount_cleanup(mp, coveredvp, 0); 1635 return (EBUSY); 1636 } 1637 mp->mnt_kern_flag |= MNTK_UNMOUNT; 1638 rootvp = vfs_cache_root_clear(mp); 1639 if (flags & MNT_NONBUSY) { 1640 MNT_IUNLOCK(mp); 1641 error = vfs_check_usecounts(mp); 1642 MNT_ILOCK(mp); 1643 if (error != 0) { 1644 dounmount_cleanup(mp, coveredvp, MNTK_UNMOUNT); 1645 if (rootvp != NULL) 1646 vrele(rootvp); 1647 return (error); 1648 } 1649 } 1650 /* Allow filesystems to detect that a forced unmount is in progress. */ 1651 if (flags & MNT_FORCE) { 1652 mp->mnt_kern_flag |= MNTK_UNMOUNTF; 1653 MNT_IUNLOCK(mp); 1654 /* 1655 * Must be done after setting MNTK_UNMOUNTF and before 1656 * waiting for mnt_lockref to become 0. 1657 */ 1658 VFS_PURGE(mp); 1659 MNT_ILOCK(mp); 1660 } 1661 error = 0; 1662 if (mp->mnt_lockref) { 1663 mp->mnt_kern_flag |= MNTK_DRAINING; 1664 error = msleep(&mp->mnt_lockref, MNT_MTX(mp), PVFS, 1665 "mount drain", 0); 1666 } 1667 MNT_IUNLOCK(mp); 1668 KASSERT(mp->mnt_lockref == 0, 1669 ("%s: invalid lock refcount in the drain path @ %s:%d", 1670 __func__, __FILE__, __LINE__)); 1671 KASSERT(error == 0, 1672 ("%s: invalid return value for msleep in the drain path @ %s:%d", 1673 __func__, __FILE__, __LINE__)); 1674 1675 if (rootvp != NULL) 1676 vrele(rootvp); 1677 1678 if (mp->mnt_flag & MNT_EXPUBLIC) 1679 vfs_setpublicfs(NULL, NULL, NULL); 1680 1681 /* 1682 * From now, we can claim that the use reference on the 1683 * coveredvp is ours, and the ref can be released only by 1684 * successfull unmount by us, or left for later unmount 1685 * attempt. The previously acquired hold reference is no 1686 * longer needed to protect the vnode from reuse. 1687 */ 1688 if (coveredvp != NULL) 1689 vdrop(coveredvp); 1690 1691 vfs_periodic(mp, MNT_WAIT); 1692 MNT_ILOCK(mp); 1693 async_flag = mp->mnt_flag & MNT_ASYNC; 1694 mp->mnt_flag &= ~MNT_ASYNC; 1695 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1696 MNT_IUNLOCK(mp); 1697 cache_purgevfs(mp, false); /* remove cache entries for this file sys */ 1698 vfs_deallocate_syncvnode(mp); 1699 error = VFS_UNMOUNT(mp, flags); 1700 vn_finished_write(mp); 1701 /* 1702 * If we failed to flush the dirty blocks for this mount point, 1703 * undo all the cdir/rdir and rootvnode changes we made above. 1704 * Unless we failed to do so because the device is reporting that 1705 * it doesn't exist anymore. 1706 */ 1707 if (error && error != ENXIO) { 1708 MNT_ILOCK(mp); 1709 if ((mp->mnt_flag & MNT_RDONLY) == 0) { 1710 MNT_IUNLOCK(mp); 1711 vfs_allocate_syncvnode(mp); 1712 MNT_ILOCK(mp); 1713 } 1714 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 1715 mp->mnt_flag |= async_flag; 1716 if ((mp->mnt_flag & MNT_ASYNC) != 0 && 1717 (mp->mnt_kern_flag & MNTK_NOASYNC) == 0) 1718 mp->mnt_kern_flag |= MNTK_ASYNC; 1719 if (mp->mnt_kern_flag & MNTK_MWAIT) { 1720 mp->mnt_kern_flag &= ~MNTK_MWAIT; 1721 wakeup(mp); 1722 } 1723 vfs_op_exit_locked(mp); 1724 MNT_IUNLOCK(mp); 1725 if (coveredvp) 1726 VOP_UNLOCK(coveredvp); 1727 return (error); 1728 } 1729 mtx_lock(&mountlist_mtx); 1730 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1731 mtx_unlock(&mountlist_mtx); 1732 EVENTHANDLER_DIRECT_INVOKE(vfs_unmounted, mp, td); 1733 if (coveredvp != NULL) { 1734 coveredvp->v_mountedhere = NULL; 1735 VOP_UNLOCK(coveredvp); 1736 } 1737 vfs_event_signal(NULL, VQ_UNMOUNT, 0); 1738 if (rootvnode != NULL && mp == rootvnode->v_mount) { 1739 vrele(rootvnode); 1740 rootvnode = NULL; 1741 } 1742 if (mp == rootdevmp) 1743 rootdevmp = NULL; 1744 vfs_mount_destroy(mp); 1745 return (0); 1746 } 1747 1748 /* 1749 * Report errors during filesystem mounting. 1750 */ 1751 void 1752 vfs_mount_error(struct mount *mp, const char *fmt, ...) 1753 { 1754 struct vfsoptlist *moptlist = mp->mnt_optnew; 1755 va_list ap; 1756 int error, len; 1757 char *errmsg; 1758 1759 error = vfs_getopt(moptlist, "errmsg", (void **)&errmsg, &len); 1760 if (error || errmsg == NULL || len <= 0) 1761 return; 1762 1763 va_start(ap, fmt); 1764 vsnprintf(errmsg, (size_t)len, fmt, ap); 1765 va_end(ap); 1766 } 1767 1768 void 1769 vfs_opterror(struct vfsoptlist *opts, const char *fmt, ...) 1770 { 1771 va_list ap; 1772 int error, len; 1773 char *errmsg; 1774 1775 error = vfs_getopt(opts, "errmsg", (void **)&errmsg, &len); 1776 if (error || errmsg == NULL || len <= 0) 1777 return; 1778 1779 va_start(ap, fmt); 1780 vsnprintf(errmsg, (size_t)len, fmt, ap); 1781 va_end(ap); 1782 } 1783 1784 /* 1785 * --------------------------------------------------------------------- 1786 * Functions for querying mount options/arguments from filesystems. 1787 */ 1788 1789 /* 1790 * Check that no unknown options are given 1791 */ 1792 int 1793 vfs_filteropt(struct vfsoptlist *opts, const char **legal) 1794 { 1795 struct vfsopt *opt; 1796 char errmsg[255]; 1797 const char **t, *p, *q; 1798 int ret = 0; 1799 1800 TAILQ_FOREACH(opt, opts, link) { 1801 p = opt->name; 1802 q = NULL; 1803 if (p[0] == 'n' && p[1] == 'o') 1804 q = p + 2; 1805 for(t = global_opts; *t != NULL; t++) { 1806 if (strcmp(*t, p) == 0) 1807 break; 1808 if (q != NULL) { 1809 if (strcmp(*t, q) == 0) 1810 break; 1811 } 1812 } 1813 if (*t != NULL) 1814 continue; 1815 for(t = legal; *t != NULL; t++) { 1816 if (strcmp(*t, p) == 0) 1817 break; 1818 if (q != NULL) { 1819 if (strcmp(*t, q) == 0) 1820 break; 1821 } 1822 } 1823 if (*t != NULL) 1824 continue; 1825 snprintf(errmsg, sizeof(errmsg), 1826 "mount option <%s> is unknown", p); 1827 ret = EINVAL; 1828 } 1829 if (ret != 0) { 1830 TAILQ_FOREACH(opt, opts, link) { 1831 if (strcmp(opt->name, "errmsg") == 0) { 1832 strncpy((char *)opt->value, errmsg, opt->len); 1833 break; 1834 } 1835 } 1836 if (opt == NULL) 1837 printf("%s\n", errmsg); 1838 } 1839 return (ret); 1840 } 1841 1842 /* 1843 * Get a mount option by its name. 1844 * 1845 * Return 0 if the option was found, ENOENT otherwise. 1846 * If len is non-NULL it will be filled with the length 1847 * of the option. If buf is non-NULL, it will be filled 1848 * with the address of the option. 1849 */ 1850 int 1851 vfs_getopt(struct vfsoptlist *opts, const char *name, void **buf, int *len) 1852 { 1853 struct vfsopt *opt; 1854 1855 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1856 1857 TAILQ_FOREACH(opt, opts, link) { 1858 if (strcmp(name, opt->name) == 0) { 1859 opt->seen = 1; 1860 if (len != NULL) 1861 *len = opt->len; 1862 if (buf != NULL) 1863 *buf = opt->value; 1864 return (0); 1865 } 1866 } 1867 return (ENOENT); 1868 } 1869 1870 int 1871 vfs_getopt_pos(struct vfsoptlist *opts, const char *name) 1872 { 1873 struct vfsopt *opt; 1874 1875 if (opts == NULL) 1876 return (-1); 1877 1878 TAILQ_FOREACH(opt, opts, link) { 1879 if (strcmp(name, opt->name) == 0) { 1880 opt->seen = 1; 1881 return (opt->pos); 1882 } 1883 } 1884 return (-1); 1885 } 1886 1887 int 1888 vfs_getopt_size(struct vfsoptlist *opts, const char *name, off_t *value) 1889 { 1890 char *opt_value, *vtp; 1891 quad_t iv; 1892 int error, opt_len; 1893 1894 error = vfs_getopt(opts, name, (void **)&opt_value, &opt_len); 1895 if (error != 0) 1896 return (error); 1897 if (opt_len == 0 || opt_value == NULL) 1898 return (EINVAL); 1899 if (opt_value[0] == '\0' || opt_value[opt_len - 1] != '\0') 1900 return (EINVAL); 1901 iv = strtoq(opt_value, &vtp, 0); 1902 if (vtp == opt_value || (vtp[0] != '\0' && vtp[1] != '\0')) 1903 return (EINVAL); 1904 if (iv < 0) 1905 return (EINVAL); 1906 switch (vtp[0]) { 1907 case 't': case 'T': 1908 iv *= 1024; 1909 /* FALLTHROUGH */ 1910 case 'g': case 'G': 1911 iv *= 1024; 1912 /* FALLTHROUGH */ 1913 case 'm': case 'M': 1914 iv *= 1024; 1915 /* FALLTHROUGH */ 1916 case 'k': case 'K': 1917 iv *= 1024; 1918 case '\0': 1919 break; 1920 default: 1921 return (EINVAL); 1922 } 1923 *value = iv; 1924 1925 return (0); 1926 } 1927 1928 char * 1929 vfs_getopts(struct vfsoptlist *opts, const char *name, int *error) 1930 { 1931 struct vfsopt *opt; 1932 1933 *error = 0; 1934 TAILQ_FOREACH(opt, opts, link) { 1935 if (strcmp(name, opt->name) != 0) 1936 continue; 1937 opt->seen = 1; 1938 if (opt->len == 0 || 1939 ((char *)opt->value)[opt->len - 1] != '\0') { 1940 *error = EINVAL; 1941 return (NULL); 1942 } 1943 return (opt->value); 1944 } 1945 *error = ENOENT; 1946 return (NULL); 1947 } 1948 1949 int 1950 vfs_flagopt(struct vfsoptlist *opts, const char *name, uint64_t *w, 1951 uint64_t val) 1952 { 1953 struct vfsopt *opt; 1954 1955 TAILQ_FOREACH(opt, opts, link) { 1956 if (strcmp(name, opt->name) == 0) { 1957 opt->seen = 1; 1958 if (w != NULL) 1959 *w |= val; 1960 return (1); 1961 } 1962 } 1963 if (w != NULL) 1964 *w &= ~val; 1965 return (0); 1966 } 1967 1968 int 1969 vfs_scanopt(struct vfsoptlist *opts, const char *name, const char *fmt, ...) 1970 { 1971 va_list ap; 1972 struct vfsopt *opt; 1973 int ret; 1974 1975 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1976 1977 TAILQ_FOREACH(opt, opts, link) { 1978 if (strcmp(name, opt->name) != 0) 1979 continue; 1980 opt->seen = 1; 1981 if (opt->len == 0 || opt->value == NULL) 1982 return (0); 1983 if (((char *)opt->value)[opt->len - 1] != '\0') 1984 return (0); 1985 va_start(ap, fmt); 1986 ret = vsscanf(opt->value, fmt, ap); 1987 va_end(ap); 1988 return (ret); 1989 } 1990 return (0); 1991 } 1992 1993 int 1994 vfs_setopt(struct vfsoptlist *opts, const char *name, void *value, int len) 1995 { 1996 struct vfsopt *opt; 1997 1998 TAILQ_FOREACH(opt, opts, link) { 1999 if (strcmp(name, opt->name) != 0) 2000 continue; 2001 opt->seen = 1; 2002 if (opt->value == NULL) 2003 opt->len = len; 2004 else { 2005 if (opt->len != len) 2006 return (EINVAL); 2007 bcopy(value, opt->value, len); 2008 } 2009 return (0); 2010 } 2011 return (ENOENT); 2012 } 2013 2014 int 2015 vfs_setopt_part(struct vfsoptlist *opts, const char *name, void *value, int len) 2016 { 2017 struct vfsopt *opt; 2018 2019 TAILQ_FOREACH(opt, opts, link) { 2020 if (strcmp(name, opt->name) != 0) 2021 continue; 2022 opt->seen = 1; 2023 if (opt->value == NULL) 2024 opt->len = len; 2025 else { 2026 if (opt->len < len) 2027 return (EINVAL); 2028 opt->len = len; 2029 bcopy(value, opt->value, len); 2030 } 2031 return (0); 2032 } 2033 return (ENOENT); 2034 } 2035 2036 int 2037 vfs_setopts(struct vfsoptlist *opts, const char *name, const char *value) 2038 { 2039 struct vfsopt *opt; 2040 2041 TAILQ_FOREACH(opt, opts, link) { 2042 if (strcmp(name, opt->name) != 0) 2043 continue; 2044 opt->seen = 1; 2045 if (opt->value == NULL) 2046 opt->len = strlen(value) + 1; 2047 else if (strlcpy(opt->value, value, opt->len) >= opt->len) 2048 return (EINVAL); 2049 return (0); 2050 } 2051 return (ENOENT); 2052 } 2053 2054 /* 2055 * Find and copy a mount option. 2056 * 2057 * The size of the buffer has to be specified 2058 * in len, if it is not the same length as the 2059 * mount option, EINVAL is returned. 2060 * Returns ENOENT if the option is not found. 2061 */ 2062 int 2063 vfs_copyopt(struct vfsoptlist *opts, const char *name, void *dest, int len) 2064 { 2065 struct vfsopt *opt; 2066 2067 KASSERT(opts != NULL, ("vfs_copyopt: caller passed 'opts' as NULL")); 2068 2069 TAILQ_FOREACH(opt, opts, link) { 2070 if (strcmp(name, opt->name) == 0) { 2071 opt->seen = 1; 2072 if (len != opt->len) 2073 return (EINVAL); 2074 bcopy(opt->value, dest, opt->len); 2075 return (0); 2076 } 2077 } 2078 return (ENOENT); 2079 } 2080 2081 int 2082 __vfs_statfs(struct mount *mp, struct statfs *sbp) 2083 { 2084 2085 /* 2086 * Filesystems only fill in part of the structure for updates, we 2087 * have to read the entirety first to get all content. 2088 */ 2089 memcpy(sbp, &mp->mnt_stat, sizeof(*sbp)); 2090 2091 /* 2092 * Set these in case the underlying filesystem fails to do so. 2093 */ 2094 sbp->f_version = STATFS_VERSION; 2095 sbp->f_namemax = NAME_MAX; 2096 sbp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK; 2097 2098 return (mp->mnt_op->vfs_statfs(mp, sbp)); 2099 } 2100 2101 void 2102 vfs_mountedfrom(struct mount *mp, const char *from) 2103 { 2104 2105 bzero(mp->mnt_stat.f_mntfromname, sizeof mp->mnt_stat.f_mntfromname); 2106 strlcpy(mp->mnt_stat.f_mntfromname, from, 2107 sizeof mp->mnt_stat.f_mntfromname); 2108 } 2109 2110 /* 2111 * --------------------------------------------------------------------- 2112 * This is the api for building mount args and mounting filesystems from 2113 * inside the kernel. 2114 * 2115 * The API works by accumulation of individual args. First error is 2116 * latched. 2117 * 2118 * XXX: should be documented in new manpage kernel_mount(9) 2119 */ 2120 2121 /* A memory allocation which must be freed when we are done */ 2122 struct mntaarg { 2123 SLIST_ENTRY(mntaarg) next; 2124 }; 2125 2126 /* The header for the mount arguments */ 2127 struct mntarg { 2128 struct iovec *v; 2129 int len; 2130 int error; 2131 SLIST_HEAD(, mntaarg) list; 2132 }; 2133 2134 /* 2135 * Add a boolean argument. 2136 * 2137 * flag is the boolean value. 2138 * name must start with "no". 2139 */ 2140 struct mntarg * 2141 mount_argb(struct mntarg *ma, int flag, const char *name) 2142 { 2143 2144 KASSERT(name[0] == 'n' && name[1] == 'o', 2145 ("mount_argb(...,%s): name must start with 'no'", name)); 2146 2147 return (mount_arg(ma, name + (flag ? 2 : 0), NULL, 0)); 2148 } 2149 2150 /* 2151 * Add an argument printf style 2152 */ 2153 struct mntarg * 2154 mount_argf(struct mntarg *ma, const char *name, const char *fmt, ...) 2155 { 2156 va_list ap; 2157 struct mntaarg *maa; 2158 struct sbuf *sb; 2159 int len; 2160 2161 if (ma == NULL) { 2162 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2163 SLIST_INIT(&ma->list); 2164 } 2165 if (ma->error) 2166 return (ma); 2167 2168 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 2169 M_MOUNT, M_WAITOK); 2170 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 2171 ma->v[ma->len].iov_len = strlen(name) + 1; 2172 ma->len++; 2173 2174 sb = sbuf_new_auto(); 2175 va_start(ap, fmt); 2176 sbuf_vprintf(sb, fmt, ap); 2177 va_end(ap); 2178 sbuf_finish(sb); 2179 len = sbuf_len(sb) + 1; 2180 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 2181 SLIST_INSERT_HEAD(&ma->list, maa, next); 2182 bcopy(sbuf_data(sb), maa + 1, len); 2183 sbuf_delete(sb); 2184 2185 ma->v[ma->len].iov_base = maa + 1; 2186 ma->v[ma->len].iov_len = len; 2187 ma->len++; 2188 2189 return (ma); 2190 } 2191 2192 /* 2193 * Add an argument which is a userland string. 2194 */ 2195 struct mntarg * 2196 mount_argsu(struct mntarg *ma, const char *name, const void *val, int len) 2197 { 2198 struct mntaarg *maa; 2199 char *tbuf; 2200 2201 if (val == NULL) 2202 return (ma); 2203 if (ma == NULL) { 2204 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2205 SLIST_INIT(&ma->list); 2206 } 2207 if (ma->error) 2208 return (ma); 2209 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 2210 SLIST_INSERT_HEAD(&ma->list, maa, next); 2211 tbuf = (void *)(maa + 1); 2212 ma->error = copyinstr(val, tbuf, len, NULL); 2213 return (mount_arg(ma, name, tbuf, -1)); 2214 } 2215 2216 /* 2217 * Plain argument. 2218 * 2219 * If length is -1, treat value as a C string. 2220 */ 2221 struct mntarg * 2222 mount_arg(struct mntarg *ma, const char *name, const void *val, int len) 2223 { 2224 2225 if (ma == NULL) { 2226 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2227 SLIST_INIT(&ma->list); 2228 } 2229 if (ma->error) 2230 return (ma); 2231 2232 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 2233 M_MOUNT, M_WAITOK); 2234 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 2235 ma->v[ma->len].iov_len = strlen(name) + 1; 2236 ma->len++; 2237 2238 ma->v[ma->len].iov_base = (void *)(uintptr_t)val; 2239 if (len < 0) 2240 ma->v[ma->len].iov_len = strlen(val) + 1; 2241 else 2242 ma->v[ma->len].iov_len = len; 2243 ma->len++; 2244 return (ma); 2245 } 2246 2247 /* 2248 * Free a mntarg structure 2249 */ 2250 static void 2251 free_mntarg(struct mntarg *ma) 2252 { 2253 struct mntaarg *maa; 2254 2255 while (!SLIST_EMPTY(&ma->list)) { 2256 maa = SLIST_FIRST(&ma->list); 2257 SLIST_REMOVE_HEAD(&ma->list, next); 2258 free(maa, M_MOUNT); 2259 } 2260 free(ma->v, M_MOUNT); 2261 free(ma, M_MOUNT); 2262 } 2263 2264 /* 2265 * Mount a filesystem 2266 */ 2267 int 2268 kernel_mount(struct mntarg *ma, uint64_t flags) 2269 { 2270 struct uio auio; 2271 int error; 2272 2273 KASSERT(ma != NULL, ("kernel_mount NULL ma")); 2274 KASSERT(ma->v != NULL, ("kernel_mount NULL ma->v")); 2275 KASSERT(!(ma->len & 1), ("kernel_mount odd ma->len (%d)", ma->len)); 2276 2277 auio.uio_iov = ma->v; 2278 auio.uio_iovcnt = ma->len; 2279 auio.uio_segflg = UIO_SYSSPACE; 2280 2281 error = ma->error; 2282 if (!error) 2283 error = vfs_donmount(curthread, flags, &auio); 2284 free_mntarg(ma); 2285 return (error); 2286 } 2287 2288 /* 2289 * A printflike function to mount a filesystem. 2290 */ 2291 int 2292 kernel_vmount(int flags, ...) 2293 { 2294 struct mntarg *ma = NULL; 2295 va_list ap; 2296 const char *cp; 2297 const void *vp; 2298 int error; 2299 2300 va_start(ap, flags); 2301 for (;;) { 2302 cp = va_arg(ap, const char *); 2303 if (cp == NULL) 2304 break; 2305 vp = va_arg(ap, const void *); 2306 ma = mount_arg(ma, cp, vp, (vp != NULL ? -1 : 0)); 2307 } 2308 va_end(ap); 2309 2310 error = kernel_mount(ma, flags); 2311 return (error); 2312 } 2313 2314 void 2315 vfs_oexport_conv(const struct oexport_args *oexp, struct export_args *exp) 2316 { 2317 2318 bcopy(oexp, exp, sizeof(*oexp)); 2319 exp->ex_numsecflavors = 0; 2320 } 2321