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 if (error == 0) { 1270 error = vfs_domount_first(td, vfsp, pathbuf, vp, 1271 fsflags, optlist); 1272 } 1273 free(pathbuf, M_TEMP); 1274 } else 1275 error = vfs_domount_update(td, vp, fsflags, optlist); 1276 1277 return (error); 1278 } 1279 1280 /* 1281 * Unmount a filesystem. 1282 * 1283 * Note: unmount takes a path to the vnode mounted on as argument, not 1284 * special file (as before). 1285 */ 1286 #ifndef _SYS_SYSPROTO_H_ 1287 struct unmount_args { 1288 char *path; 1289 int flags; 1290 }; 1291 #endif 1292 /* ARGSUSED */ 1293 int 1294 sys_unmount(struct thread *td, struct unmount_args *uap) 1295 { 1296 1297 return (kern_unmount(td, uap->path, uap->flags)); 1298 } 1299 1300 int 1301 kern_unmount(struct thread *td, const char *path, int flags) 1302 { 1303 struct nameidata nd; 1304 struct mount *mp; 1305 char *pathbuf; 1306 int error, id0, id1; 1307 1308 AUDIT_ARG_VALUE(flags); 1309 if (jailed(td->td_ucred) || usermount == 0) { 1310 error = priv_check(td, PRIV_VFS_UNMOUNT); 1311 if (error) 1312 return (error); 1313 } 1314 1315 pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK); 1316 error = copyinstr(path, pathbuf, MNAMELEN, NULL); 1317 if (error) { 1318 free(pathbuf, M_TEMP); 1319 return (error); 1320 } 1321 if (flags & MNT_BYFSID) { 1322 AUDIT_ARG_TEXT(pathbuf); 1323 /* Decode the filesystem ID. */ 1324 if (sscanf(pathbuf, "FSID:%d:%d", &id0, &id1) != 2) { 1325 free(pathbuf, M_TEMP); 1326 return (EINVAL); 1327 } 1328 1329 mtx_lock(&mountlist_mtx); 1330 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1331 if (mp->mnt_stat.f_fsid.val[0] == id0 && 1332 mp->mnt_stat.f_fsid.val[1] == id1) { 1333 vfs_ref(mp); 1334 break; 1335 } 1336 } 1337 mtx_unlock(&mountlist_mtx); 1338 } else { 1339 /* 1340 * Try to find global path for path argument. 1341 */ 1342 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, 1343 UIO_SYSSPACE, pathbuf, td); 1344 if (namei(&nd) == 0) { 1345 NDFREE(&nd, NDF_ONLY_PNBUF); 1346 error = vn_path_to_global_path(td, nd.ni_vp, pathbuf, 1347 MNAMELEN); 1348 if (error == 0) 1349 vput(nd.ni_vp); 1350 } 1351 mtx_lock(&mountlist_mtx); 1352 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1353 if (strcmp(mp->mnt_stat.f_mntonname, pathbuf) == 0) { 1354 vfs_ref(mp); 1355 break; 1356 } 1357 } 1358 mtx_unlock(&mountlist_mtx); 1359 } 1360 free(pathbuf, M_TEMP); 1361 if (mp == NULL) { 1362 /* 1363 * Previously we returned ENOENT for a nonexistent path and 1364 * EINVAL for a non-mountpoint. We cannot tell these apart 1365 * now, so in the !MNT_BYFSID case return the more likely 1366 * EINVAL for compatibility. 1367 */ 1368 return ((flags & MNT_BYFSID) ? ENOENT : EINVAL); 1369 } 1370 1371 /* 1372 * Don't allow unmounting the root filesystem. 1373 */ 1374 if (mp->mnt_flag & MNT_ROOTFS) { 1375 vfs_rel(mp); 1376 return (EINVAL); 1377 } 1378 error = dounmount(mp, flags, td); 1379 return (error); 1380 } 1381 1382 /* 1383 * Return error if any of the vnodes, ignoring the root vnode 1384 * and the syncer vnode, have non-zero usecount. 1385 * 1386 * This function is purely advisory - it can return false positives 1387 * and negatives. 1388 */ 1389 static int 1390 vfs_check_usecounts(struct mount *mp) 1391 { 1392 struct vnode *vp, *mvp; 1393 1394 MNT_VNODE_FOREACH_ALL(vp, mp, mvp) { 1395 if ((vp->v_vflag & VV_ROOT) == 0 && vp->v_type != VNON && 1396 vp->v_usecount != 0) { 1397 VI_UNLOCK(vp); 1398 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp); 1399 return (EBUSY); 1400 } 1401 VI_UNLOCK(vp); 1402 } 1403 1404 return (0); 1405 } 1406 1407 static void 1408 dounmount_cleanup(struct mount *mp, struct vnode *coveredvp, int mntkflags) 1409 { 1410 1411 mtx_assert(MNT_MTX(mp), MA_OWNED); 1412 mp->mnt_kern_flag &= ~mntkflags; 1413 if ((mp->mnt_kern_flag & MNTK_MWAIT) != 0) { 1414 mp->mnt_kern_flag &= ~MNTK_MWAIT; 1415 wakeup(mp); 1416 } 1417 vfs_op_exit_locked(mp); 1418 MNT_IUNLOCK(mp); 1419 if (coveredvp != NULL) { 1420 VOP_UNLOCK(coveredvp); 1421 vdrop(coveredvp); 1422 } 1423 vn_finished_write(mp); 1424 } 1425 1426 /* 1427 * There are various reference counters associated with the mount point. 1428 * Normally it is permitted to modify them without taking the mnt ilock, 1429 * but this behavior can be temporarily disabled if stable value is needed 1430 * or callers are expected to block (e.g. to not allow new users during 1431 * forced unmount). 1432 */ 1433 void 1434 vfs_op_enter(struct mount *mp) 1435 { 1436 int cpu; 1437 1438 MNT_ILOCK(mp); 1439 mp->mnt_vfs_ops++; 1440 if (mp->mnt_vfs_ops > 1) { 1441 MNT_IUNLOCK(mp); 1442 return; 1443 } 1444 vfs_op_barrier_wait(mp); 1445 CPU_FOREACH(cpu) { 1446 mp->mnt_ref += 1447 zpcpu_replace_cpu(mp->mnt_ref_pcpu, 0, cpu); 1448 mp->mnt_lockref += 1449 zpcpu_replace_cpu(mp->mnt_lockref_pcpu, 0, cpu); 1450 mp->mnt_writeopcount += 1451 zpcpu_replace_cpu(mp->mnt_writeopcount_pcpu, 0, cpu); 1452 } 1453 MNT_IUNLOCK(mp); 1454 vfs_assert_mount_counters(mp); 1455 } 1456 1457 void 1458 vfs_op_exit_locked(struct mount *mp) 1459 { 1460 1461 mtx_assert(MNT_MTX(mp), MA_OWNED); 1462 1463 if (mp->mnt_vfs_ops <= 0) 1464 panic("%s: invalid vfs_ops count %d for mp %p\n", 1465 __func__, mp->mnt_vfs_ops, mp); 1466 mp->mnt_vfs_ops--; 1467 } 1468 1469 void 1470 vfs_op_exit(struct mount *mp) 1471 { 1472 1473 MNT_ILOCK(mp); 1474 vfs_op_exit_locked(mp); 1475 MNT_IUNLOCK(mp); 1476 } 1477 1478 struct vfs_op_barrier_ipi { 1479 struct mount *mp; 1480 struct smp_rendezvous_cpus_retry_arg srcra; 1481 }; 1482 1483 static void 1484 vfs_op_action_func(void *arg) 1485 { 1486 struct vfs_op_barrier_ipi *vfsopipi; 1487 struct mount *mp; 1488 1489 vfsopipi = __containerof(arg, struct vfs_op_barrier_ipi, srcra); 1490 mp = vfsopipi->mp; 1491 1492 if (!vfs_op_thread_entered(mp)) 1493 smp_rendezvous_cpus_done(arg); 1494 } 1495 1496 static void 1497 vfs_op_wait_func(void *arg, int cpu) 1498 { 1499 struct vfs_op_barrier_ipi *vfsopipi; 1500 struct mount *mp; 1501 int *in_op; 1502 1503 vfsopipi = __containerof(arg, struct vfs_op_barrier_ipi, srcra); 1504 mp = vfsopipi->mp; 1505 1506 in_op = zpcpu_get_cpu(mp->mnt_thread_in_ops_pcpu, cpu); 1507 while (atomic_load_int(in_op)) 1508 cpu_spinwait(); 1509 } 1510 1511 void 1512 vfs_op_barrier_wait(struct mount *mp) 1513 { 1514 struct vfs_op_barrier_ipi vfsopipi; 1515 1516 vfsopipi.mp = mp; 1517 1518 smp_rendezvous_cpus_retry(all_cpus, 1519 smp_no_rendezvous_barrier, 1520 vfs_op_action_func, 1521 smp_no_rendezvous_barrier, 1522 vfs_op_wait_func, 1523 &vfsopipi.srcra); 1524 } 1525 1526 #ifdef DIAGNOSTIC 1527 void 1528 vfs_assert_mount_counters(struct mount *mp) 1529 { 1530 int cpu; 1531 1532 if (mp->mnt_vfs_ops == 0) 1533 return; 1534 1535 CPU_FOREACH(cpu) { 1536 if (*zpcpu_get_cpu(mp->mnt_ref_pcpu, cpu) != 0 || 1537 *zpcpu_get_cpu(mp->mnt_lockref_pcpu, cpu) != 0 || 1538 *zpcpu_get_cpu(mp->mnt_writeopcount_pcpu, cpu) != 0) 1539 vfs_dump_mount_counters(mp); 1540 } 1541 } 1542 1543 void 1544 vfs_dump_mount_counters(struct mount *mp) 1545 { 1546 int cpu, *count; 1547 int ref, lockref, writeopcount; 1548 1549 printf("%s: mp %p vfs_ops %d\n", __func__, mp, mp->mnt_vfs_ops); 1550 1551 printf(" ref : "); 1552 ref = mp->mnt_ref; 1553 CPU_FOREACH(cpu) { 1554 count = zpcpu_get_cpu(mp->mnt_ref_pcpu, cpu); 1555 printf("%d ", *count); 1556 ref += *count; 1557 } 1558 printf("\n"); 1559 printf(" lockref : "); 1560 lockref = mp->mnt_lockref; 1561 CPU_FOREACH(cpu) { 1562 count = zpcpu_get_cpu(mp->mnt_lockref_pcpu, cpu); 1563 printf("%d ", *count); 1564 lockref += *count; 1565 } 1566 printf("\n"); 1567 printf("writeopcount: "); 1568 writeopcount = mp->mnt_writeopcount; 1569 CPU_FOREACH(cpu) { 1570 count = zpcpu_get_cpu(mp->mnt_writeopcount_pcpu, cpu); 1571 printf("%d ", *count); 1572 writeopcount += *count; 1573 } 1574 printf("\n"); 1575 1576 printf("counter struct total\n"); 1577 printf("ref %-5d %-5d\n", mp->mnt_ref, ref); 1578 printf("lockref %-5d %-5d\n", mp->mnt_lockref, lockref); 1579 printf("writeopcount %-5d %-5d\n", mp->mnt_writeopcount, writeopcount); 1580 1581 panic("invalid counts on struct mount"); 1582 } 1583 #endif 1584 1585 int 1586 vfs_mount_fetch_counter(struct mount *mp, enum mount_counter which) 1587 { 1588 int *base, *pcpu; 1589 int cpu, sum; 1590 1591 switch (which) { 1592 case MNT_COUNT_REF: 1593 base = &mp->mnt_ref; 1594 pcpu = mp->mnt_ref_pcpu; 1595 break; 1596 case MNT_COUNT_LOCKREF: 1597 base = &mp->mnt_lockref; 1598 pcpu = mp->mnt_lockref_pcpu; 1599 break; 1600 case MNT_COUNT_WRITEOPCOUNT: 1601 base = &mp->mnt_writeopcount; 1602 pcpu = mp->mnt_writeopcount_pcpu; 1603 break; 1604 } 1605 1606 sum = *base; 1607 CPU_FOREACH(cpu) { 1608 sum += *zpcpu_get_cpu(pcpu, cpu); 1609 } 1610 return (sum); 1611 } 1612 1613 /* 1614 * Do the actual filesystem unmount. 1615 */ 1616 int 1617 dounmount(struct mount *mp, int flags, struct thread *td) 1618 { 1619 struct vnode *coveredvp, *rootvp; 1620 int error; 1621 uint64_t async_flag; 1622 int mnt_gen_r; 1623 1624 if ((coveredvp = mp->mnt_vnodecovered) != NULL) { 1625 mnt_gen_r = mp->mnt_gen; 1626 VI_LOCK(coveredvp); 1627 vholdl(coveredvp); 1628 vn_lock(coveredvp, LK_EXCLUSIVE | LK_INTERLOCK | LK_RETRY); 1629 /* 1630 * Check for mp being unmounted while waiting for the 1631 * covered vnode lock. 1632 */ 1633 if (coveredvp->v_mountedhere != mp || 1634 coveredvp->v_mountedhere->mnt_gen != mnt_gen_r) { 1635 VOP_UNLOCK(coveredvp); 1636 vdrop(coveredvp); 1637 vfs_rel(mp); 1638 return (EBUSY); 1639 } 1640 } 1641 1642 /* 1643 * Only privileged root, or (if MNT_USER is set) the user that did the 1644 * original mount is permitted to unmount this filesystem. 1645 */ 1646 error = vfs_suser(mp, td); 1647 if (error != 0) { 1648 if (coveredvp != NULL) { 1649 VOP_UNLOCK(coveredvp); 1650 vdrop(coveredvp); 1651 } 1652 vfs_rel(mp); 1653 return (error); 1654 } 1655 1656 vfs_op_enter(mp); 1657 1658 vn_start_write(NULL, &mp, V_WAIT | V_MNTREF); 1659 MNT_ILOCK(mp); 1660 if ((mp->mnt_kern_flag & MNTK_UNMOUNT) != 0 || 1661 (mp->mnt_flag & MNT_UPDATE) != 0 || 1662 !TAILQ_EMPTY(&mp->mnt_uppers)) { 1663 dounmount_cleanup(mp, coveredvp, 0); 1664 return (EBUSY); 1665 } 1666 mp->mnt_kern_flag |= MNTK_UNMOUNT; 1667 rootvp = vfs_cache_root_clear(mp); 1668 if (flags & MNT_NONBUSY) { 1669 MNT_IUNLOCK(mp); 1670 error = vfs_check_usecounts(mp); 1671 MNT_ILOCK(mp); 1672 if (error != 0) { 1673 dounmount_cleanup(mp, coveredvp, MNTK_UNMOUNT); 1674 if (rootvp != NULL) 1675 vrele(rootvp); 1676 return (error); 1677 } 1678 } 1679 /* Allow filesystems to detect that a forced unmount is in progress. */ 1680 if (flags & MNT_FORCE) { 1681 mp->mnt_kern_flag |= MNTK_UNMOUNTF; 1682 MNT_IUNLOCK(mp); 1683 /* 1684 * Must be done after setting MNTK_UNMOUNTF and before 1685 * waiting for mnt_lockref to become 0. 1686 */ 1687 VFS_PURGE(mp); 1688 MNT_ILOCK(mp); 1689 } 1690 error = 0; 1691 if (mp->mnt_lockref) { 1692 mp->mnt_kern_flag |= MNTK_DRAINING; 1693 error = msleep(&mp->mnt_lockref, MNT_MTX(mp), PVFS, 1694 "mount drain", 0); 1695 } 1696 MNT_IUNLOCK(mp); 1697 KASSERT(mp->mnt_lockref == 0, 1698 ("%s: invalid lock refcount in the drain path @ %s:%d", 1699 __func__, __FILE__, __LINE__)); 1700 KASSERT(error == 0, 1701 ("%s: invalid return value for msleep in the drain path @ %s:%d", 1702 __func__, __FILE__, __LINE__)); 1703 1704 if (rootvp != NULL) 1705 vrele(rootvp); 1706 1707 if (mp->mnt_flag & MNT_EXPUBLIC) 1708 vfs_setpublicfs(NULL, NULL, NULL); 1709 1710 /* 1711 * From now, we can claim that the use reference on the 1712 * coveredvp is ours, and the ref can be released only by 1713 * successfull unmount by us, or left for later unmount 1714 * attempt. The previously acquired hold reference is no 1715 * longer needed to protect the vnode from reuse. 1716 */ 1717 if (coveredvp != NULL) 1718 vdrop(coveredvp); 1719 1720 vfs_periodic(mp, MNT_WAIT); 1721 MNT_ILOCK(mp); 1722 async_flag = mp->mnt_flag & MNT_ASYNC; 1723 mp->mnt_flag &= ~MNT_ASYNC; 1724 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1725 MNT_IUNLOCK(mp); 1726 cache_purgevfs(mp, false); /* remove cache entries for this file sys */ 1727 vfs_deallocate_syncvnode(mp); 1728 error = VFS_UNMOUNT(mp, flags); 1729 vn_finished_write(mp); 1730 /* 1731 * If we failed to flush the dirty blocks for this mount point, 1732 * undo all the cdir/rdir and rootvnode changes we made above. 1733 * Unless we failed to do so because the device is reporting that 1734 * it doesn't exist anymore. 1735 */ 1736 if (error && error != ENXIO) { 1737 MNT_ILOCK(mp); 1738 if ((mp->mnt_flag & MNT_RDONLY) == 0) { 1739 MNT_IUNLOCK(mp); 1740 vfs_allocate_syncvnode(mp); 1741 MNT_ILOCK(mp); 1742 } 1743 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 1744 mp->mnt_flag |= async_flag; 1745 if ((mp->mnt_flag & MNT_ASYNC) != 0 && 1746 (mp->mnt_kern_flag & MNTK_NOASYNC) == 0) 1747 mp->mnt_kern_flag |= MNTK_ASYNC; 1748 if (mp->mnt_kern_flag & MNTK_MWAIT) { 1749 mp->mnt_kern_flag &= ~MNTK_MWAIT; 1750 wakeup(mp); 1751 } 1752 vfs_op_exit_locked(mp); 1753 MNT_IUNLOCK(mp); 1754 if (coveredvp) 1755 VOP_UNLOCK(coveredvp); 1756 return (error); 1757 } 1758 mtx_lock(&mountlist_mtx); 1759 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1760 mtx_unlock(&mountlist_mtx); 1761 EVENTHANDLER_DIRECT_INVOKE(vfs_unmounted, mp, td); 1762 if (coveredvp != NULL) { 1763 coveredvp->v_mountedhere = NULL; 1764 VOP_UNLOCK(coveredvp); 1765 } 1766 vfs_event_signal(NULL, VQ_UNMOUNT, 0); 1767 if (rootvnode != NULL && mp == rootvnode->v_mount) { 1768 vrele(rootvnode); 1769 rootvnode = NULL; 1770 } 1771 if (mp == rootdevmp) 1772 rootdevmp = NULL; 1773 vfs_mount_destroy(mp); 1774 return (0); 1775 } 1776 1777 /* 1778 * Report errors during filesystem mounting. 1779 */ 1780 void 1781 vfs_mount_error(struct mount *mp, const char *fmt, ...) 1782 { 1783 struct vfsoptlist *moptlist = mp->mnt_optnew; 1784 va_list ap; 1785 int error, len; 1786 char *errmsg; 1787 1788 error = vfs_getopt(moptlist, "errmsg", (void **)&errmsg, &len); 1789 if (error || errmsg == NULL || len <= 0) 1790 return; 1791 1792 va_start(ap, fmt); 1793 vsnprintf(errmsg, (size_t)len, fmt, ap); 1794 va_end(ap); 1795 } 1796 1797 void 1798 vfs_opterror(struct vfsoptlist *opts, const char *fmt, ...) 1799 { 1800 va_list ap; 1801 int error, len; 1802 char *errmsg; 1803 1804 error = vfs_getopt(opts, "errmsg", (void **)&errmsg, &len); 1805 if (error || errmsg == NULL || len <= 0) 1806 return; 1807 1808 va_start(ap, fmt); 1809 vsnprintf(errmsg, (size_t)len, fmt, ap); 1810 va_end(ap); 1811 } 1812 1813 /* 1814 * --------------------------------------------------------------------- 1815 * Functions for querying mount options/arguments from filesystems. 1816 */ 1817 1818 /* 1819 * Check that no unknown options are given 1820 */ 1821 int 1822 vfs_filteropt(struct vfsoptlist *opts, const char **legal) 1823 { 1824 struct vfsopt *opt; 1825 char errmsg[255]; 1826 const char **t, *p, *q; 1827 int ret = 0; 1828 1829 TAILQ_FOREACH(opt, opts, link) { 1830 p = opt->name; 1831 q = NULL; 1832 if (p[0] == 'n' && p[1] == 'o') 1833 q = p + 2; 1834 for(t = global_opts; *t != NULL; t++) { 1835 if (strcmp(*t, p) == 0) 1836 break; 1837 if (q != NULL) { 1838 if (strcmp(*t, q) == 0) 1839 break; 1840 } 1841 } 1842 if (*t != NULL) 1843 continue; 1844 for(t = legal; *t != NULL; t++) { 1845 if (strcmp(*t, p) == 0) 1846 break; 1847 if (q != NULL) { 1848 if (strcmp(*t, q) == 0) 1849 break; 1850 } 1851 } 1852 if (*t != NULL) 1853 continue; 1854 snprintf(errmsg, sizeof(errmsg), 1855 "mount option <%s> is unknown", p); 1856 ret = EINVAL; 1857 } 1858 if (ret != 0) { 1859 TAILQ_FOREACH(opt, opts, link) { 1860 if (strcmp(opt->name, "errmsg") == 0) { 1861 strncpy((char *)opt->value, errmsg, opt->len); 1862 break; 1863 } 1864 } 1865 if (opt == NULL) 1866 printf("%s\n", errmsg); 1867 } 1868 return (ret); 1869 } 1870 1871 /* 1872 * Get a mount option by its name. 1873 * 1874 * Return 0 if the option was found, ENOENT otherwise. 1875 * If len is non-NULL it will be filled with the length 1876 * of the option. If buf is non-NULL, it will be filled 1877 * with the address of the option. 1878 */ 1879 int 1880 vfs_getopt(struct vfsoptlist *opts, const char *name, void **buf, int *len) 1881 { 1882 struct vfsopt *opt; 1883 1884 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1885 1886 TAILQ_FOREACH(opt, opts, link) { 1887 if (strcmp(name, opt->name) == 0) { 1888 opt->seen = 1; 1889 if (len != NULL) 1890 *len = opt->len; 1891 if (buf != NULL) 1892 *buf = opt->value; 1893 return (0); 1894 } 1895 } 1896 return (ENOENT); 1897 } 1898 1899 int 1900 vfs_getopt_pos(struct vfsoptlist *opts, const char *name) 1901 { 1902 struct vfsopt *opt; 1903 1904 if (opts == NULL) 1905 return (-1); 1906 1907 TAILQ_FOREACH(opt, opts, link) { 1908 if (strcmp(name, opt->name) == 0) { 1909 opt->seen = 1; 1910 return (opt->pos); 1911 } 1912 } 1913 return (-1); 1914 } 1915 1916 int 1917 vfs_getopt_size(struct vfsoptlist *opts, const char *name, off_t *value) 1918 { 1919 char *opt_value, *vtp; 1920 quad_t iv; 1921 int error, opt_len; 1922 1923 error = vfs_getopt(opts, name, (void **)&opt_value, &opt_len); 1924 if (error != 0) 1925 return (error); 1926 if (opt_len == 0 || opt_value == NULL) 1927 return (EINVAL); 1928 if (opt_value[0] == '\0' || opt_value[opt_len - 1] != '\0') 1929 return (EINVAL); 1930 iv = strtoq(opt_value, &vtp, 0); 1931 if (vtp == opt_value || (vtp[0] != '\0' && vtp[1] != '\0')) 1932 return (EINVAL); 1933 if (iv < 0) 1934 return (EINVAL); 1935 switch (vtp[0]) { 1936 case 't': case 'T': 1937 iv *= 1024; 1938 /* FALLTHROUGH */ 1939 case 'g': case 'G': 1940 iv *= 1024; 1941 /* FALLTHROUGH */ 1942 case 'm': case 'M': 1943 iv *= 1024; 1944 /* FALLTHROUGH */ 1945 case 'k': case 'K': 1946 iv *= 1024; 1947 case '\0': 1948 break; 1949 default: 1950 return (EINVAL); 1951 } 1952 *value = iv; 1953 1954 return (0); 1955 } 1956 1957 char * 1958 vfs_getopts(struct vfsoptlist *opts, const char *name, int *error) 1959 { 1960 struct vfsopt *opt; 1961 1962 *error = 0; 1963 TAILQ_FOREACH(opt, opts, link) { 1964 if (strcmp(name, opt->name) != 0) 1965 continue; 1966 opt->seen = 1; 1967 if (opt->len == 0 || 1968 ((char *)opt->value)[opt->len - 1] != '\0') { 1969 *error = EINVAL; 1970 return (NULL); 1971 } 1972 return (opt->value); 1973 } 1974 *error = ENOENT; 1975 return (NULL); 1976 } 1977 1978 int 1979 vfs_flagopt(struct vfsoptlist *opts, const char *name, uint64_t *w, 1980 uint64_t val) 1981 { 1982 struct vfsopt *opt; 1983 1984 TAILQ_FOREACH(opt, opts, link) { 1985 if (strcmp(name, opt->name) == 0) { 1986 opt->seen = 1; 1987 if (w != NULL) 1988 *w |= val; 1989 return (1); 1990 } 1991 } 1992 if (w != NULL) 1993 *w &= ~val; 1994 return (0); 1995 } 1996 1997 int 1998 vfs_scanopt(struct vfsoptlist *opts, const char *name, const char *fmt, ...) 1999 { 2000 va_list ap; 2001 struct vfsopt *opt; 2002 int ret; 2003 2004 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 2005 2006 TAILQ_FOREACH(opt, opts, link) { 2007 if (strcmp(name, opt->name) != 0) 2008 continue; 2009 opt->seen = 1; 2010 if (opt->len == 0 || opt->value == NULL) 2011 return (0); 2012 if (((char *)opt->value)[opt->len - 1] != '\0') 2013 return (0); 2014 va_start(ap, fmt); 2015 ret = vsscanf(opt->value, fmt, ap); 2016 va_end(ap); 2017 return (ret); 2018 } 2019 return (0); 2020 } 2021 2022 int 2023 vfs_setopt(struct vfsoptlist *opts, const char *name, void *value, int len) 2024 { 2025 struct vfsopt *opt; 2026 2027 TAILQ_FOREACH(opt, opts, link) { 2028 if (strcmp(name, opt->name) != 0) 2029 continue; 2030 opt->seen = 1; 2031 if (opt->value == NULL) 2032 opt->len = len; 2033 else { 2034 if (opt->len != len) 2035 return (EINVAL); 2036 bcopy(value, opt->value, len); 2037 } 2038 return (0); 2039 } 2040 return (ENOENT); 2041 } 2042 2043 int 2044 vfs_setopt_part(struct vfsoptlist *opts, const char *name, void *value, int len) 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 = len; 2054 else { 2055 if (opt->len < len) 2056 return (EINVAL); 2057 opt->len = len; 2058 bcopy(value, opt->value, len); 2059 } 2060 return (0); 2061 } 2062 return (ENOENT); 2063 } 2064 2065 int 2066 vfs_setopts(struct vfsoptlist *opts, const char *name, const char *value) 2067 { 2068 struct vfsopt *opt; 2069 2070 TAILQ_FOREACH(opt, opts, link) { 2071 if (strcmp(name, opt->name) != 0) 2072 continue; 2073 opt->seen = 1; 2074 if (opt->value == NULL) 2075 opt->len = strlen(value) + 1; 2076 else if (strlcpy(opt->value, value, opt->len) >= opt->len) 2077 return (EINVAL); 2078 return (0); 2079 } 2080 return (ENOENT); 2081 } 2082 2083 /* 2084 * Find and copy a mount option. 2085 * 2086 * The size of the buffer has to be specified 2087 * in len, if it is not the same length as the 2088 * mount option, EINVAL is returned. 2089 * Returns ENOENT if the option is not found. 2090 */ 2091 int 2092 vfs_copyopt(struct vfsoptlist *opts, const char *name, void *dest, int len) 2093 { 2094 struct vfsopt *opt; 2095 2096 KASSERT(opts != NULL, ("vfs_copyopt: caller passed 'opts' as NULL")); 2097 2098 TAILQ_FOREACH(opt, opts, link) { 2099 if (strcmp(name, opt->name) == 0) { 2100 opt->seen = 1; 2101 if (len != opt->len) 2102 return (EINVAL); 2103 bcopy(opt->value, dest, opt->len); 2104 return (0); 2105 } 2106 } 2107 return (ENOENT); 2108 } 2109 2110 int 2111 __vfs_statfs(struct mount *mp, struct statfs *sbp) 2112 { 2113 2114 /* 2115 * Filesystems only fill in part of the structure for updates, we 2116 * have to read the entirety first to get all content. 2117 */ 2118 memcpy(sbp, &mp->mnt_stat, sizeof(*sbp)); 2119 2120 /* 2121 * Set these in case the underlying filesystem fails to do so. 2122 */ 2123 sbp->f_version = STATFS_VERSION; 2124 sbp->f_namemax = NAME_MAX; 2125 sbp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK; 2126 2127 return (mp->mnt_op->vfs_statfs(mp, sbp)); 2128 } 2129 2130 void 2131 vfs_mountedfrom(struct mount *mp, const char *from) 2132 { 2133 2134 bzero(mp->mnt_stat.f_mntfromname, sizeof mp->mnt_stat.f_mntfromname); 2135 strlcpy(mp->mnt_stat.f_mntfromname, from, 2136 sizeof mp->mnt_stat.f_mntfromname); 2137 } 2138 2139 /* 2140 * --------------------------------------------------------------------- 2141 * This is the api for building mount args and mounting filesystems from 2142 * inside the kernel. 2143 * 2144 * The API works by accumulation of individual args. First error is 2145 * latched. 2146 * 2147 * XXX: should be documented in new manpage kernel_mount(9) 2148 */ 2149 2150 /* A memory allocation which must be freed when we are done */ 2151 struct mntaarg { 2152 SLIST_ENTRY(mntaarg) next; 2153 }; 2154 2155 /* The header for the mount arguments */ 2156 struct mntarg { 2157 struct iovec *v; 2158 int len; 2159 int error; 2160 SLIST_HEAD(, mntaarg) list; 2161 }; 2162 2163 /* 2164 * Add a boolean argument. 2165 * 2166 * flag is the boolean value. 2167 * name must start with "no". 2168 */ 2169 struct mntarg * 2170 mount_argb(struct mntarg *ma, int flag, const char *name) 2171 { 2172 2173 KASSERT(name[0] == 'n' && name[1] == 'o', 2174 ("mount_argb(...,%s): name must start with 'no'", name)); 2175 2176 return (mount_arg(ma, name + (flag ? 2 : 0), NULL, 0)); 2177 } 2178 2179 /* 2180 * Add an argument printf style 2181 */ 2182 struct mntarg * 2183 mount_argf(struct mntarg *ma, const char *name, const char *fmt, ...) 2184 { 2185 va_list ap; 2186 struct mntaarg *maa; 2187 struct sbuf *sb; 2188 int len; 2189 2190 if (ma == NULL) { 2191 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2192 SLIST_INIT(&ma->list); 2193 } 2194 if (ma->error) 2195 return (ma); 2196 2197 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 2198 M_MOUNT, M_WAITOK); 2199 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 2200 ma->v[ma->len].iov_len = strlen(name) + 1; 2201 ma->len++; 2202 2203 sb = sbuf_new_auto(); 2204 va_start(ap, fmt); 2205 sbuf_vprintf(sb, fmt, ap); 2206 va_end(ap); 2207 sbuf_finish(sb); 2208 len = sbuf_len(sb) + 1; 2209 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 2210 SLIST_INSERT_HEAD(&ma->list, maa, next); 2211 bcopy(sbuf_data(sb), maa + 1, len); 2212 sbuf_delete(sb); 2213 2214 ma->v[ma->len].iov_base = maa + 1; 2215 ma->v[ma->len].iov_len = len; 2216 ma->len++; 2217 2218 return (ma); 2219 } 2220 2221 /* 2222 * Add an argument which is a userland string. 2223 */ 2224 struct mntarg * 2225 mount_argsu(struct mntarg *ma, const char *name, const void *val, int len) 2226 { 2227 struct mntaarg *maa; 2228 char *tbuf; 2229 2230 if (val == NULL) 2231 return (ma); 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 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 2239 SLIST_INSERT_HEAD(&ma->list, maa, next); 2240 tbuf = (void *)(maa + 1); 2241 ma->error = copyinstr(val, tbuf, len, NULL); 2242 return (mount_arg(ma, name, tbuf, -1)); 2243 } 2244 2245 /* 2246 * Plain argument. 2247 * 2248 * If length is -1, treat value as a C string. 2249 */ 2250 struct mntarg * 2251 mount_arg(struct mntarg *ma, const char *name, const void *val, int len) 2252 { 2253 2254 if (ma == NULL) { 2255 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2256 SLIST_INIT(&ma->list); 2257 } 2258 if (ma->error) 2259 return (ma); 2260 2261 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 2262 M_MOUNT, M_WAITOK); 2263 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 2264 ma->v[ma->len].iov_len = strlen(name) + 1; 2265 ma->len++; 2266 2267 ma->v[ma->len].iov_base = (void *)(uintptr_t)val; 2268 if (len < 0) 2269 ma->v[ma->len].iov_len = strlen(val) + 1; 2270 else 2271 ma->v[ma->len].iov_len = len; 2272 ma->len++; 2273 return (ma); 2274 } 2275 2276 /* 2277 * Free a mntarg structure 2278 */ 2279 static void 2280 free_mntarg(struct mntarg *ma) 2281 { 2282 struct mntaarg *maa; 2283 2284 while (!SLIST_EMPTY(&ma->list)) { 2285 maa = SLIST_FIRST(&ma->list); 2286 SLIST_REMOVE_HEAD(&ma->list, next); 2287 free(maa, M_MOUNT); 2288 } 2289 free(ma->v, M_MOUNT); 2290 free(ma, M_MOUNT); 2291 } 2292 2293 /* 2294 * Mount a filesystem 2295 */ 2296 int 2297 kernel_mount(struct mntarg *ma, uint64_t flags) 2298 { 2299 struct uio auio; 2300 int error; 2301 2302 KASSERT(ma != NULL, ("kernel_mount NULL ma")); 2303 KASSERT(ma->v != NULL, ("kernel_mount NULL ma->v")); 2304 KASSERT(!(ma->len & 1), ("kernel_mount odd ma->len (%d)", ma->len)); 2305 2306 auio.uio_iov = ma->v; 2307 auio.uio_iovcnt = ma->len; 2308 auio.uio_segflg = UIO_SYSSPACE; 2309 2310 error = ma->error; 2311 if (!error) 2312 error = vfs_donmount(curthread, flags, &auio); 2313 free_mntarg(ma); 2314 return (error); 2315 } 2316 2317 /* 2318 * A printflike function to mount a filesystem. 2319 */ 2320 int 2321 kernel_vmount(int flags, ...) 2322 { 2323 struct mntarg *ma = NULL; 2324 va_list ap; 2325 const char *cp; 2326 const void *vp; 2327 int error; 2328 2329 va_start(ap, flags); 2330 for (;;) { 2331 cp = va_arg(ap, const char *); 2332 if (cp == NULL) 2333 break; 2334 vp = va_arg(ap, const void *); 2335 ma = mount_arg(ma, cp, vp, (vp != NULL ? -1 : 0)); 2336 } 2337 va_end(ap); 2338 2339 error = kernel_mount(ma, flags); 2340 return (error); 2341 } 2342 2343 void 2344 vfs_oexport_conv(const struct oexport_args *oexp, struct export_args *exp) 2345 { 2346 2347 bcopy(oexp, exp, sizeof(*oexp)); 2348 exp->ex_numsecflavors = 0; 2349 } 2350