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 <rpc/types.h> 74 #include <rpc/auth.h> 75 76 #include <security/audit/audit.h> 77 #include <security/mac/mac_framework.h> 78 79 #define VFS_MOUNTARG_SIZE_MAX (1024 * 64) 80 81 static int vfs_domount(struct thread *td, const char *fstype, char *fspath, 82 uint64_t fsflags, struct vfsoptlist **optlist); 83 static void free_mntarg(struct mntarg *ma); 84 85 static int usermount = 0; 86 SYSCTL_INT(_vfs, OID_AUTO, usermount, CTLFLAG_RW, &usermount, 0, 87 "Unprivileged users may mount and unmount file systems"); 88 89 static bool default_autoro = false; 90 SYSCTL_BOOL(_vfs, OID_AUTO, default_autoro, CTLFLAG_RW, &default_autoro, 0, 91 "Retry failed r/w mount as r/o if no explicit ro/rw option is specified"); 92 93 MALLOC_DEFINE(M_MOUNT, "mount", "vfs mount structure"); 94 MALLOC_DEFINE(M_STATFS, "statfs", "statfs structure"); 95 static uma_zone_t mount_zone; 96 97 /* List of mounted filesystems. */ 98 struct mntlist mountlist = TAILQ_HEAD_INITIALIZER(mountlist); 99 100 /* For any iteration/modification of mountlist */ 101 struct mtx mountlist_mtx; 102 MTX_SYSINIT(mountlist, &mountlist_mtx, "mountlist", MTX_DEF); 103 104 EVENTHANDLER_LIST_DEFINE(vfs_mounted); 105 EVENTHANDLER_LIST_DEFINE(vfs_unmounted); 106 107 /* 108 * Global opts, taken by all filesystems 109 */ 110 static const char *global_opts[] = { 111 "errmsg", 112 "fstype", 113 "fspath", 114 "ro", 115 "rw", 116 "nosuid", 117 "noexec", 118 NULL 119 }; 120 121 static int 122 mount_init(void *mem, int size, int flags) 123 { 124 struct mount *mp; 125 126 mp = (struct mount *)mem; 127 mtx_init(&mp->mnt_mtx, "struct mount mtx", NULL, MTX_DEF); 128 mtx_init(&mp->mnt_listmtx, "struct mount vlist mtx", NULL, MTX_DEF); 129 lockinit(&mp->mnt_explock, PVFS, "explock", 0, 0); 130 mp->mnt_thread_in_ops_pcpu = uma_zalloc_pcpu(pcpu_zone_int, 131 M_WAITOK | M_ZERO); 132 mp->mnt_ref_pcpu = uma_zalloc_pcpu(pcpu_zone_int, 133 M_WAITOK | M_ZERO); 134 mp->mnt_lockref_pcpu = uma_zalloc_pcpu(pcpu_zone_int, 135 M_WAITOK | M_ZERO); 136 mp->mnt_writeopcount_pcpu = uma_zalloc_pcpu(pcpu_zone_int, 137 M_WAITOK | M_ZERO); 138 mp->mnt_ref = 0; 139 mp->mnt_vfs_ops = 1; 140 mp->mnt_rootvnode = NULL; 141 return (0); 142 } 143 144 static void 145 mount_fini(void *mem, int size) 146 { 147 struct mount *mp; 148 149 mp = (struct mount *)mem; 150 uma_zfree_pcpu(pcpu_zone_int, mp->mnt_writeopcount_pcpu); 151 uma_zfree_pcpu(pcpu_zone_int, mp->mnt_lockref_pcpu); 152 uma_zfree_pcpu(pcpu_zone_int, mp->mnt_ref_pcpu); 153 uma_zfree_pcpu(pcpu_zone_int, mp->mnt_thread_in_ops_pcpu); 154 lockdestroy(&mp->mnt_explock); 155 mtx_destroy(&mp->mnt_listmtx); 156 mtx_destroy(&mp->mnt_mtx); 157 } 158 159 static void 160 vfs_mount_init(void *dummy __unused) 161 { 162 163 mount_zone = uma_zcreate("Mountpoints", sizeof(struct mount), NULL, 164 NULL, mount_init, mount_fini, UMA_ALIGN_CACHE, UMA_ZONE_NOFREE); 165 } 166 SYSINIT(vfs_mount, SI_SUB_VFS, SI_ORDER_ANY, vfs_mount_init, NULL); 167 168 /* 169 * --------------------------------------------------------------------- 170 * Functions for building and sanitizing the mount options 171 */ 172 173 /* Remove one mount option. */ 174 static void 175 vfs_freeopt(struct vfsoptlist *opts, struct vfsopt *opt) 176 { 177 178 TAILQ_REMOVE(opts, opt, link); 179 free(opt->name, M_MOUNT); 180 if (opt->value != NULL) 181 free(opt->value, M_MOUNT); 182 free(opt, M_MOUNT); 183 } 184 185 /* Release all resources related to the mount options. */ 186 void 187 vfs_freeopts(struct vfsoptlist *opts) 188 { 189 struct vfsopt *opt; 190 191 while (!TAILQ_EMPTY(opts)) { 192 opt = TAILQ_FIRST(opts); 193 vfs_freeopt(opts, opt); 194 } 195 free(opts, M_MOUNT); 196 } 197 198 void 199 vfs_deleteopt(struct vfsoptlist *opts, const char *name) 200 { 201 struct vfsopt *opt, *temp; 202 203 if (opts == NULL) 204 return; 205 TAILQ_FOREACH_SAFE(opt, opts, link, temp) { 206 if (strcmp(opt->name, name) == 0) 207 vfs_freeopt(opts, opt); 208 } 209 } 210 211 static int 212 vfs_isopt_ro(const char *opt) 213 { 214 215 if (strcmp(opt, "ro") == 0 || strcmp(opt, "rdonly") == 0 || 216 strcmp(opt, "norw") == 0) 217 return (1); 218 return (0); 219 } 220 221 static int 222 vfs_isopt_rw(const char *opt) 223 { 224 225 if (strcmp(opt, "rw") == 0 || strcmp(opt, "noro") == 0) 226 return (1); 227 return (0); 228 } 229 230 /* 231 * Check if options are equal (with or without the "no" prefix). 232 */ 233 static int 234 vfs_equalopts(const char *opt1, const char *opt2) 235 { 236 char *p; 237 238 /* "opt" vs. "opt" or "noopt" vs. "noopt" */ 239 if (strcmp(opt1, opt2) == 0) 240 return (1); 241 /* "noopt" vs. "opt" */ 242 if (strncmp(opt1, "no", 2) == 0 && strcmp(opt1 + 2, opt2) == 0) 243 return (1); 244 /* "opt" vs. "noopt" */ 245 if (strncmp(opt2, "no", 2) == 0 && strcmp(opt1, opt2 + 2) == 0) 246 return (1); 247 while ((p = strchr(opt1, '.')) != NULL && 248 !strncmp(opt1, opt2, ++p - opt1)) { 249 opt2 += p - opt1; 250 opt1 = p; 251 /* "foo.noopt" vs. "foo.opt" */ 252 if (strncmp(opt1, "no", 2) == 0 && strcmp(opt1 + 2, opt2) == 0) 253 return (1); 254 /* "foo.opt" vs. "foo.noopt" */ 255 if (strncmp(opt2, "no", 2) == 0 && strcmp(opt1, opt2 + 2) == 0) 256 return (1); 257 } 258 /* "ro" / "rdonly" / "norw" / "rw" / "noro" */ 259 if ((vfs_isopt_ro(opt1) || vfs_isopt_rw(opt1)) && 260 (vfs_isopt_ro(opt2) || vfs_isopt_rw(opt2))) 261 return (1); 262 return (0); 263 } 264 265 /* 266 * If a mount option is specified several times, 267 * (with or without the "no" prefix) only keep 268 * the last occurrence of it. 269 */ 270 static void 271 vfs_sanitizeopts(struct vfsoptlist *opts) 272 { 273 struct vfsopt *opt, *opt2, *tmp; 274 275 TAILQ_FOREACH_REVERSE(opt, opts, vfsoptlist, link) { 276 opt2 = TAILQ_PREV(opt, vfsoptlist, link); 277 while (opt2 != NULL) { 278 if (vfs_equalopts(opt->name, opt2->name)) { 279 tmp = TAILQ_PREV(opt2, vfsoptlist, link); 280 vfs_freeopt(opts, opt2); 281 opt2 = tmp; 282 } else { 283 opt2 = TAILQ_PREV(opt2, vfsoptlist, link); 284 } 285 } 286 } 287 } 288 289 /* 290 * Build a linked list of mount options from a struct uio. 291 */ 292 int 293 vfs_buildopts(struct uio *auio, struct vfsoptlist **options) 294 { 295 struct vfsoptlist *opts; 296 struct vfsopt *opt; 297 size_t memused, namelen, optlen; 298 unsigned int i, iovcnt; 299 int error; 300 301 opts = malloc(sizeof(struct vfsoptlist), M_MOUNT, M_WAITOK); 302 TAILQ_INIT(opts); 303 memused = 0; 304 iovcnt = auio->uio_iovcnt; 305 for (i = 0; i < iovcnt; i += 2) { 306 namelen = auio->uio_iov[i].iov_len; 307 optlen = auio->uio_iov[i + 1].iov_len; 308 memused += sizeof(struct vfsopt) + optlen + namelen; 309 /* 310 * Avoid consuming too much memory, and attempts to overflow 311 * memused. 312 */ 313 if (memused > VFS_MOUNTARG_SIZE_MAX || 314 optlen > VFS_MOUNTARG_SIZE_MAX || 315 namelen > VFS_MOUNTARG_SIZE_MAX) { 316 error = EINVAL; 317 goto bad; 318 } 319 320 opt = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 321 opt->name = malloc(namelen, M_MOUNT, M_WAITOK); 322 opt->value = NULL; 323 opt->len = 0; 324 opt->pos = i / 2; 325 opt->seen = 0; 326 327 /* 328 * Do this early, so jumps to "bad" will free the current 329 * option. 330 */ 331 TAILQ_INSERT_TAIL(opts, opt, link); 332 333 if (auio->uio_segflg == UIO_SYSSPACE) { 334 bcopy(auio->uio_iov[i].iov_base, opt->name, namelen); 335 } else { 336 error = copyin(auio->uio_iov[i].iov_base, opt->name, 337 namelen); 338 if (error) 339 goto bad; 340 } 341 /* Ensure names are null-terminated strings. */ 342 if (namelen == 0 || opt->name[namelen - 1] != '\0') { 343 error = EINVAL; 344 goto bad; 345 } 346 if (optlen != 0) { 347 opt->len = optlen; 348 opt->value = malloc(optlen, M_MOUNT, M_WAITOK); 349 if (auio->uio_segflg == UIO_SYSSPACE) { 350 bcopy(auio->uio_iov[i + 1].iov_base, opt->value, 351 optlen); 352 } else { 353 error = copyin(auio->uio_iov[i + 1].iov_base, 354 opt->value, optlen); 355 if (error) 356 goto bad; 357 } 358 } 359 } 360 vfs_sanitizeopts(opts); 361 *options = opts; 362 return (0); 363 bad: 364 vfs_freeopts(opts); 365 return (error); 366 } 367 368 /* 369 * Merge the old mount options with the new ones passed 370 * in the MNT_UPDATE case. 371 * 372 * XXX: This function will keep a "nofoo" option in the new 373 * options. E.g, if the option's canonical name is "foo", 374 * "nofoo" ends up in the mount point's active options. 375 */ 376 static void 377 vfs_mergeopts(struct vfsoptlist *toopts, struct vfsoptlist *oldopts) 378 { 379 struct vfsopt *opt, *new; 380 381 TAILQ_FOREACH(opt, oldopts, link) { 382 new = malloc(sizeof(struct vfsopt), M_MOUNT, M_WAITOK); 383 new->name = strdup(opt->name, M_MOUNT); 384 if (opt->len != 0) { 385 new->value = malloc(opt->len, M_MOUNT, M_WAITOK); 386 bcopy(opt->value, new->value, opt->len); 387 } else 388 new->value = NULL; 389 new->len = opt->len; 390 new->seen = opt->seen; 391 TAILQ_INSERT_HEAD(toopts, new, link); 392 } 393 vfs_sanitizeopts(toopts); 394 } 395 396 /* 397 * Mount a filesystem. 398 */ 399 #ifndef _SYS_SYSPROTO_H_ 400 struct nmount_args { 401 struct iovec *iovp; 402 unsigned int iovcnt; 403 int flags; 404 }; 405 #endif 406 int 407 sys_nmount(struct thread *td, struct nmount_args *uap) 408 { 409 struct uio *auio; 410 int error; 411 u_int iovcnt; 412 uint64_t flags; 413 414 /* 415 * Mount flags are now 64-bits. On 32-bit archtectures only 416 * 32-bits are passed in, but from here on everything handles 417 * 64-bit flags correctly. 418 */ 419 flags = uap->flags; 420 421 AUDIT_ARG_FFLAGS(flags); 422 CTR4(KTR_VFS, "%s: iovp %p with iovcnt %d and flags %d", __func__, 423 uap->iovp, uap->iovcnt, flags); 424 425 /* 426 * Filter out MNT_ROOTFS. We do not want clients of nmount() in 427 * userspace to set this flag, but we must filter it out if we want 428 * MNT_UPDATE on the root file system to work. 429 * MNT_ROOTFS should only be set by the kernel when mounting its 430 * root file system. 431 */ 432 flags &= ~MNT_ROOTFS; 433 434 iovcnt = uap->iovcnt; 435 /* 436 * Check that we have an even number of iovec's 437 * and that we have at least two options. 438 */ 439 if ((iovcnt & 1) || (iovcnt < 4)) { 440 CTR2(KTR_VFS, "%s: failed for invalid iovcnt %d", __func__, 441 uap->iovcnt); 442 return (EINVAL); 443 } 444 445 error = copyinuio(uap->iovp, iovcnt, &auio); 446 if (error) { 447 CTR2(KTR_VFS, "%s: failed for invalid uio op with %d errno", 448 __func__, error); 449 return (error); 450 } 451 error = vfs_donmount(td, flags, auio); 452 453 free(auio, M_IOV); 454 return (error); 455 } 456 457 /* 458 * --------------------------------------------------------------------- 459 * Various utility functions 460 */ 461 462 void 463 vfs_ref(struct mount *mp) 464 { 465 466 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 467 if (vfs_op_thread_enter(mp)) { 468 vfs_mp_count_add_pcpu(mp, ref, 1); 469 vfs_op_thread_exit(mp); 470 return; 471 } 472 473 MNT_ILOCK(mp); 474 MNT_REF(mp); 475 MNT_IUNLOCK(mp); 476 } 477 478 void 479 vfs_rel(struct mount *mp) 480 { 481 482 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 483 if (vfs_op_thread_enter(mp)) { 484 vfs_mp_count_sub_pcpu(mp, ref, 1); 485 vfs_op_thread_exit(mp); 486 return; 487 } 488 489 MNT_ILOCK(mp); 490 MNT_REL(mp); 491 MNT_IUNLOCK(mp); 492 } 493 494 /* 495 * Allocate and initialize the mount point struct. 496 */ 497 struct mount * 498 vfs_mount_alloc(struct vnode *vp, struct vfsconf *vfsp, const char *fspath, 499 struct ucred *cred) 500 { 501 struct mount *mp; 502 503 mp = uma_zalloc(mount_zone, M_WAITOK); 504 bzero(&mp->mnt_startzero, 505 __rangeof(struct mount, mnt_startzero, mnt_endzero)); 506 TAILQ_INIT(&mp->mnt_nvnodelist); 507 mp->mnt_nvnodelistsize = 0; 508 TAILQ_INIT(&mp->mnt_lazyvnodelist); 509 mp->mnt_lazyvnodelistsize = 0; 510 if (mp->mnt_ref != 0 || mp->mnt_lockref != 0 || 511 mp->mnt_writeopcount != 0) 512 panic("%s: non-zero counters on new mp %p\n", __func__, mp); 513 if (mp->mnt_vfs_ops != 1) 514 panic("%s: vfs_ops should be 1 but %d found\n", __func__, 515 mp->mnt_vfs_ops); 516 (void) vfs_busy(mp, MBF_NOWAIT); 517 atomic_add_acq_int(&vfsp->vfc_refcount, 1); 518 mp->mnt_op = vfsp->vfc_vfsops; 519 mp->mnt_vfc = vfsp; 520 mp->mnt_stat.f_type = vfsp->vfc_typenum; 521 mp->mnt_gen++; 522 strlcpy(mp->mnt_stat.f_fstypename, vfsp->vfc_name, MFSNAMELEN); 523 mp->mnt_vnodecovered = vp; 524 mp->mnt_cred = crdup(cred); 525 mp->mnt_stat.f_owner = cred->cr_uid; 526 strlcpy(mp->mnt_stat.f_mntonname, fspath, MNAMELEN); 527 mp->mnt_iosize_max = DFLTPHYS; 528 #ifdef MAC 529 mac_mount_init(mp); 530 mac_mount_create(cred, mp); 531 #endif 532 arc4rand(&mp->mnt_hashseed, sizeof mp->mnt_hashseed, 0); 533 TAILQ_INIT(&mp->mnt_uppers); 534 return (mp); 535 } 536 537 /* 538 * Destroy the mount struct previously allocated by vfs_mount_alloc(). 539 */ 540 void 541 vfs_mount_destroy(struct mount *mp) 542 { 543 544 if (mp->mnt_vfs_ops == 0) 545 panic("%s: entered with zero vfs_ops\n", __func__); 546 547 vfs_assert_mount_counters(mp); 548 549 MNT_ILOCK(mp); 550 mp->mnt_kern_flag |= MNTK_REFEXPIRE; 551 if (mp->mnt_kern_flag & MNTK_MWAIT) { 552 mp->mnt_kern_flag &= ~MNTK_MWAIT; 553 wakeup(mp); 554 } 555 while (mp->mnt_ref) 556 msleep(mp, MNT_MTX(mp), PVFS, "mntref", 0); 557 KASSERT(mp->mnt_ref == 0, 558 ("%s: invalid refcount in the drain path @ %s:%d", __func__, 559 __FILE__, __LINE__)); 560 if (mp->mnt_writeopcount != 0) 561 panic("vfs_mount_destroy: nonzero writeopcount"); 562 if (mp->mnt_secondary_writes != 0) 563 panic("vfs_mount_destroy: nonzero secondary_writes"); 564 atomic_subtract_rel_int(&mp->mnt_vfc->vfc_refcount, 1); 565 if (!TAILQ_EMPTY(&mp->mnt_nvnodelist)) { 566 struct vnode *vp; 567 568 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) 569 vn_printf(vp, "dangling vnode "); 570 panic("unmount: dangling vnode"); 571 } 572 KASSERT(TAILQ_EMPTY(&mp->mnt_uppers), ("mnt_uppers")); 573 if (mp->mnt_nvnodelistsize != 0) 574 panic("vfs_mount_destroy: nonzero nvnodelistsize"); 575 if (mp->mnt_lazyvnodelistsize != 0) 576 panic("vfs_mount_destroy: nonzero lazyvnodelistsize"); 577 if (mp->mnt_lockref != 0) 578 panic("vfs_mount_destroy: nonzero lock refcount"); 579 MNT_IUNLOCK(mp); 580 581 if (mp->mnt_vfs_ops != 1) 582 panic("%s: vfs_ops should be 1 but %d found\n", __func__, 583 mp->mnt_vfs_ops); 584 585 if (mp->mnt_rootvnode != NULL) 586 panic("%s: mount point still has a root vnode %p\n", __func__, 587 mp->mnt_rootvnode); 588 589 if (mp->mnt_vnodecovered != NULL) 590 vrele(mp->mnt_vnodecovered); 591 #ifdef MAC 592 mac_mount_destroy(mp); 593 #endif 594 if (mp->mnt_opt != NULL) 595 vfs_freeopts(mp->mnt_opt); 596 crfree(mp->mnt_cred); 597 uma_zfree(mount_zone, mp); 598 } 599 600 static bool 601 vfs_should_downgrade_to_ro_mount(uint64_t fsflags, int error) 602 { 603 /* This is an upgrade of an exisiting mount. */ 604 if ((fsflags & MNT_UPDATE) != 0) 605 return (false); 606 /* This is already an R/O mount. */ 607 if ((fsflags & MNT_RDONLY) != 0) 608 return (false); 609 610 switch (error) { 611 case ENODEV: /* generic, geom, ... */ 612 case EACCES: /* cam/scsi, ... */ 613 case EROFS: /* md, mmcsd, ... */ 614 /* 615 * These errors can be returned by the storage layer to signal 616 * that the media is read-only. No harm in the R/O mount 617 * attempt if the error was returned for some other reason. 618 */ 619 return (true); 620 default: 621 return (false); 622 } 623 } 624 625 int 626 vfs_donmount(struct thread *td, uint64_t fsflags, struct uio *fsoptions) 627 { 628 struct vfsoptlist *optlist; 629 struct vfsopt *opt, *tmp_opt; 630 char *fstype, *fspath, *errmsg; 631 int error, fstypelen, fspathlen, errmsg_len, errmsg_pos; 632 bool autoro; 633 634 errmsg = fspath = NULL; 635 errmsg_len = fspathlen = 0; 636 errmsg_pos = -1; 637 autoro = default_autoro; 638 639 error = vfs_buildopts(fsoptions, &optlist); 640 if (error) 641 return (error); 642 643 if (vfs_getopt(optlist, "errmsg", (void **)&errmsg, &errmsg_len) == 0) 644 errmsg_pos = vfs_getopt_pos(optlist, "errmsg"); 645 646 /* 647 * We need these two options before the others, 648 * and they are mandatory for any filesystem. 649 * Ensure they are NUL terminated as well. 650 */ 651 fstypelen = 0; 652 error = vfs_getopt(optlist, "fstype", (void **)&fstype, &fstypelen); 653 if (error || fstypelen <= 0 || fstype[fstypelen - 1] != '\0') { 654 error = EINVAL; 655 if (errmsg != NULL) 656 strncpy(errmsg, "Invalid fstype", errmsg_len); 657 goto bail; 658 } 659 fspathlen = 0; 660 error = vfs_getopt(optlist, "fspath", (void **)&fspath, &fspathlen); 661 if (error || fspathlen <= 0 || fspath[fspathlen - 1] != '\0') { 662 error = EINVAL; 663 if (errmsg != NULL) 664 strncpy(errmsg, "Invalid fspath", errmsg_len); 665 goto bail; 666 } 667 668 /* 669 * We need to see if we have the "update" option 670 * before we call vfs_domount(), since vfs_domount() has special 671 * logic based on MNT_UPDATE. This is very important 672 * when we want to update the root filesystem. 673 */ 674 TAILQ_FOREACH_SAFE(opt, optlist, link, tmp_opt) { 675 int do_freeopt = 0; 676 677 if (strcmp(opt->name, "update") == 0) { 678 fsflags |= MNT_UPDATE; 679 do_freeopt = 1; 680 } 681 else if (strcmp(opt->name, "async") == 0) 682 fsflags |= MNT_ASYNC; 683 else if (strcmp(opt->name, "force") == 0) { 684 fsflags |= MNT_FORCE; 685 do_freeopt = 1; 686 } 687 else if (strcmp(opt->name, "reload") == 0) { 688 fsflags |= MNT_RELOAD; 689 do_freeopt = 1; 690 } 691 else if (strcmp(opt->name, "multilabel") == 0) 692 fsflags |= MNT_MULTILABEL; 693 else if (strcmp(opt->name, "noasync") == 0) 694 fsflags &= ~MNT_ASYNC; 695 else if (strcmp(opt->name, "noatime") == 0) 696 fsflags |= MNT_NOATIME; 697 else if (strcmp(opt->name, "atime") == 0) { 698 free(opt->name, M_MOUNT); 699 opt->name = strdup("nonoatime", M_MOUNT); 700 } 701 else if (strcmp(opt->name, "noclusterr") == 0) 702 fsflags |= MNT_NOCLUSTERR; 703 else if (strcmp(opt->name, "clusterr") == 0) { 704 free(opt->name, M_MOUNT); 705 opt->name = strdup("nonoclusterr", M_MOUNT); 706 } 707 else if (strcmp(opt->name, "noclusterw") == 0) 708 fsflags |= MNT_NOCLUSTERW; 709 else if (strcmp(opt->name, "clusterw") == 0) { 710 free(opt->name, M_MOUNT); 711 opt->name = strdup("nonoclusterw", M_MOUNT); 712 } 713 else if (strcmp(opt->name, "noexec") == 0) 714 fsflags |= MNT_NOEXEC; 715 else if (strcmp(opt->name, "exec") == 0) { 716 free(opt->name, M_MOUNT); 717 opt->name = strdup("nonoexec", M_MOUNT); 718 } 719 else if (strcmp(opt->name, "nosuid") == 0) 720 fsflags |= MNT_NOSUID; 721 else if (strcmp(opt->name, "suid") == 0) { 722 free(opt->name, M_MOUNT); 723 opt->name = strdup("nonosuid", M_MOUNT); 724 } 725 else if (strcmp(opt->name, "nosymfollow") == 0) 726 fsflags |= MNT_NOSYMFOLLOW; 727 else if (strcmp(opt->name, "symfollow") == 0) { 728 free(opt->name, M_MOUNT); 729 opt->name = strdup("nonosymfollow", M_MOUNT); 730 } 731 else if (strcmp(opt->name, "noro") == 0) { 732 fsflags &= ~MNT_RDONLY; 733 autoro = false; 734 } 735 else if (strcmp(opt->name, "rw") == 0) { 736 fsflags &= ~MNT_RDONLY; 737 autoro = false; 738 } 739 else if (strcmp(opt->name, "ro") == 0) { 740 fsflags |= MNT_RDONLY; 741 autoro = false; 742 } 743 else if (strcmp(opt->name, "rdonly") == 0) { 744 free(opt->name, M_MOUNT); 745 opt->name = strdup("ro", M_MOUNT); 746 fsflags |= MNT_RDONLY; 747 autoro = false; 748 } 749 else if (strcmp(opt->name, "autoro") == 0) { 750 do_freeopt = 1; 751 autoro = true; 752 } 753 else if (strcmp(opt->name, "suiddir") == 0) 754 fsflags |= MNT_SUIDDIR; 755 else if (strcmp(opt->name, "sync") == 0) 756 fsflags |= MNT_SYNCHRONOUS; 757 else if (strcmp(opt->name, "union") == 0) 758 fsflags |= MNT_UNION; 759 else if (strcmp(opt->name, "automounted") == 0) { 760 fsflags |= MNT_AUTOMOUNTED; 761 do_freeopt = 1; 762 } else if (strcmp(opt->name, "nocover") == 0) { 763 fsflags |= MNT_NOCOVER; 764 do_freeopt = 1; 765 } else if (strcmp(opt->name, "cover") == 0) { 766 fsflags &= ~MNT_NOCOVER; 767 do_freeopt = 1; 768 } else if (strcmp(opt->name, "emptydir") == 0) { 769 fsflags |= MNT_EMPTYDIR; 770 do_freeopt = 1; 771 } else if (strcmp(opt->name, "noemptydir") == 0) { 772 fsflags &= ~MNT_EMPTYDIR; 773 do_freeopt = 1; 774 } 775 if (do_freeopt) 776 vfs_freeopt(optlist, opt); 777 } 778 779 /* 780 * Be ultra-paranoid about making sure the type and fspath 781 * variables will fit in our mp buffers, including the 782 * terminating NUL. 783 */ 784 if (fstypelen > MFSNAMELEN || fspathlen > MNAMELEN) { 785 error = ENAMETOOLONG; 786 goto bail; 787 } 788 789 error = vfs_domount(td, fstype, fspath, fsflags, &optlist); 790 791 /* 792 * See if we can mount in the read-only mode if the error code suggests 793 * that it could be possible and the mount options allow for that. 794 * Never try it if "[no]{ro|rw}" has been explicitly requested and not 795 * overridden by "autoro". 796 */ 797 if (autoro && vfs_should_downgrade_to_ro_mount(fsflags, error)) { 798 printf("%s: R/W mount failed, possibly R/O media," 799 " trying R/O mount\n", __func__); 800 fsflags |= MNT_RDONLY; 801 error = vfs_domount(td, fstype, fspath, fsflags, &optlist); 802 } 803 bail: 804 /* copyout the errmsg */ 805 if (errmsg_pos != -1 && ((2 * errmsg_pos + 1) < fsoptions->uio_iovcnt) 806 && errmsg_len > 0 && errmsg != NULL) { 807 if (fsoptions->uio_segflg == UIO_SYSSPACE) { 808 bcopy(errmsg, 809 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_base, 810 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_len); 811 } else { 812 copyout(errmsg, 813 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_base, 814 fsoptions->uio_iov[2 * errmsg_pos + 1].iov_len); 815 } 816 } 817 818 if (optlist != NULL) 819 vfs_freeopts(optlist); 820 return (error); 821 } 822 823 /* 824 * Old mount API. 825 */ 826 #ifndef _SYS_SYSPROTO_H_ 827 struct mount_args { 828 char *type; 829 char *path; 830 int flags; 831 caddr_t data; 832 }; 833 #endif 834 /* ARGSUSED */ 835 int 836 sys_mount(struct thread *td, struct mount_args *uap) 837 { 838 char *fstype; 839 struct vfsconf *vfsp = NULL; 840 struct mntarg *ma = NULL; 841 uint64_t flags; 842 int error; 843 844 /* 845 * Mount flags are now 64-bits. On 32-bit architectures only 846 * 32-bits are passed in, but from here on everything handles 847 * 64-bit flags correctly. 848 */ 849 flags = uap->flags; 850 851 AUDIT_ARG_FFLAGS(flags); 852 853 /* 854 * Filter out MNT_ROOTFS. We do not want clients of mount() in 855 * userspace to set this flag, but we must filter it out if we want 856 * MNT_UPDATE on the root file system to work. 857 * MNT_ROOTFS should only be set by the kernel when mounting its 858 * root file system. 859 */ 860 flags &= ~MNT_ROOTFS; 861 862 fstype = malloc(MFSNAMELEN, M_TEMP, M_WAITOK); 863 error = copyinstr(uap->type, fstype, MFSNAMELEN, NULL); 864 if (error) { 865 free(fstype, M_TEMP); 866 return (error); 867 } 868 869 AUDIT_ARG_TEXT(fstype); 870 vfsp = vfs_byname_kld(fstype, td, &error); 871 free(fstype, M_TEMP); 872 if (vfsp == NULL) 873 return (ENOENT); 874 if (((vfsp->vfc_flags & VFCF_SBDRY) != 0 && 875 vfsp->vfc_vfsops_sd->vfs_cmount == NULL) || 876 ((vfsp->vfc_flags & VFCF_SBDRY) == 0 && 877 vfsp->vfc_vfsops->vfs_cmount == NULL)) 878 return (EOPNOTSUPP); 879 880 ma = mount_argsu(ma, "fstype", uap->type, MFSNAMELEN); 881 ma = mount_argsu(ma, "fspath", uap->path, MNAMELEN); 882 ma = mount_argb(ma, flags & MNT_RDONLY, "noro"); 883 ma = mount_argb(ma, !(flags & MNT_NOSUID), "nosuid"); 884 ma = mount_argb(ma, !(flags & MNT_NOEXEC), "noexec"); 885 886 if ((vfsp->vfc_flags & VFCF_SBDRY) != 0) 887 return (vfsp->vfc_vfsops_sd->vfs_cmount(ma, uap->data, flags)); 888 return (vfsp->vfc_vfsops->vfs_cmount(ma, uap->data, flags)); 889 } 890 891 /* 892 * vfs_domount_first(): first file system mount (not update) 893 */ 894 static int 895 vfs_domount_first( 896 struct thread *td, /* Calling thread. */ 897 struct vfsconf *vfsp, /* File system type. */ 898 char *fspath, /* Mount path. */ 899 struct vnode *vp, /* Vnode to be covered. */ 900 uint64_t fsflags, /* Flags common to all filesystems. */ 901 struct vfsoptlist **optlist /* Options local to the filesystem. */ 902 ) 903 { 904 struct vattr va; 905 struct mount *mp; 906 struct vnode *newdp, *rootvp; 907 int error, error1; 908 909 ASSERT_VOP_ELOCKED(vp, __func__); 910 KASSERT((fsflags & MNT_UPDATE) == 0, ("MNT_UPDATE shouldn't be here")); 911 912 if ((fsflags & MNT_EMPTYDIR) != 0) { 913 error = vfs_emptydir(vp); 914 if (error != 0) { 915 vput(vp); 916 return (error); 917 } 918 } 919 920 /* 921 * If the jail of the calling thread lacks permission for this type of 922 * file system, deny immediately. 923 */ 924 if (jailed(td->td_ucred) && !prison_allow(td->td_ucred, 925 vfsp->vfc_prison_flag)) { 926 vput(vp); 927 return (EPERM); 928 } 929 930 /* 931 * If the user is not root, ensure that they own the directory 932 * onto which we are attempting to mount. 933 */ 934 error = VOP_GETATTR(vp, &va, td->td_ucred); 935 if (error == 0 && va.va_uid != td->td_ucred->cr_uid) 936 error = priv_check_cred(td->td_ucred, PRIV_VFS_ADMIN); 937 if (error == 0) 938 error = vinvalbuf(vp, V_SAVE, 0, 0); 939 if (error == 0 && vp->v_type != VDIR) 940 error = ENOTDIR; 941 if (error == 0) { 942 VI_LOCK(vp); 943 if ((vp->v_iflag & VI_MOUNT) == 0 && vp->v_mountedhere == NULL) 944 vp->v_iflag |= VI_MOUNT; 945 else 946 error = EBUSY; 947 VI_UNLOCK(vp); 948 } 949 if (error != 0) { 950 vput(vp); 951 return (error); 952 } 953 VOP_UNLOCK(vp); 954 955 /* Allocate and initialize the filesystem. */ 956 mp = vfs_mount_alloc(vp, vfsp, fspath, td->td_ucred); 957 /* XXXMAC: pass to vfs_mount_alloc? */ 958 mp->mnt_optnew = *optlist; 959 /* Set the mount level flags. */ 960 mp->mnt_flag = (fsflags & (MNT_UPDATEMASK | MNT_ROOTFS | MNT_RDONLY)); 961 962 /* 963 * Mount the filesystem. 964 * XXX The final recipients of VFS_MOUNT just overwrite the ndp they 965 * get. No freeing of cn_pnbuf. 966 */ 967 error1 = 0; 968 if ((error = VFS_MOUNT(mp)) != 0 || 969 (error1 = VFS_STATFS(mp, &mp->mnt_stat)) != 0 || 970 (error1 = VFS_ROOT(mp, LK_EXCLUSIVE, &newdp)) != 0) { 971 if (error1 != 0) { 972 error = error1; 973 rootvp = vfs_cache_root_clear(mp); 974 if (rootvp != NULL) 975 vrele(rootvp); 976 if ((error1 = VFS_UNMOUNT(mp, 0)) != 0) 977 printf("VFS_UNMOUNT returned %d\n", error1); 978 } 979 vfs_unbusy(mp); 980 mp->mnt_vnodecovered = NULL; 981 vfs_mount_destroy(mp); 982 VI_LOCK(vp); 983 vp->v_iflag &= ~VI_MOUNT; 984 VI_UNLOCK(vp); 985 vrele(vp); 986 return (error); 987 } 988 VOP_UNLOCK(newdp); 989 990 if (mp->mnt_opt != NULL) 991 vfs_freeopts(mp->mnt_opt); 992 mp->mnt_opt = mp->mnt_optnew; 993 *optlist = NULL; 994 995 /* 996 * Prevent external consumers of mount options from reading mnt_optnew. 997 */ 998 mp->mnt_optnew = NULL; 999 1000 MNT_ILOCK(mp); 1001 if ((mp->mnt_flag & MNT_ASYNC) != 0 && 1002 (mp->mnt_kern_flag & MNTK_NOASYNC) == 0) 1003 mp->mnt_kern_flag |= MNTK_ASYNC; 1004 else 1005 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1006 MNT_IUNLOCK(mp); 1007 1008 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1009 cache_purge(vp); 1010 VI_LOCK(vp); 1011 vp->v_iflag &= ~VI_MOUNT; 1012 VI_UNLOCK(vp); 1013 vp->v_mountedhere = mp; 1014 /* Place the new filesystem at the end of the mount list. */ 1015 mtx_lock(&mountlist_mtx); 1016 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list); 1017 mtx_unlock(&mountlist_mtx); 1018 vfs_event_signal(NULL, VQ_MOUNT, 0); 1019 vn_lock(newdp, LK_EXCLUSIVE | LK_RETRY); 1020 VOP_UNLOCK(vp); 1021 EVENTHANDLER_DIRECT_INVOKE(vfs_mounted, mp, newdp, td); 1022 VOP_UNLOCK(newdp); 1023 mountcheckdirs(vp, newdp); 1024 vrele(newdp); 1025 if ((mp->mnt_flag & MNT_RDONLY) == 0) 1026 vfs_allocate_syncvnode(mp); 1027 vfs_op_exit(mp); 1028 vfs_unbusy(mp); 1029 return (0); 1030 } 1031 1032 /* 1033 * vfs_domount_update(): update of mounted file system 1034 */ 1035 static int 1036 vfs_domount_update( 1037 struct thread *td, /* Calling thread. */ 1038 struct vnode *vp, /* Mount point vnode. */ 1039 uint64_t fsflags, /* Flags common to all filesystems. */ 1040 struct vfsoptlist **optlist /* Options local to the filesystem. */ 1041 ) 1042 { 1043 struct export_args export; 1044 struct vnode *rootvp; 1045 void *bufp; 1046 struct mount *mp; 1047 int error, export_error, len; 1048 uint64_t flag; 1049 1050 ASSERT_VOP_ELOCKED(vp, __func__); 1051 KASSERT((fsflags & MNT_UPDATE) != 0, ("MNT_UPDATE should be here")); 1052 mp = vp->v_mount; 1053 1054 if ((vp->v_vflag & VV_ROOT) == 0) { 1055 if (vfs_copyopt(*optlist, "export", &export, sizeof(export)) 1056 == 0) 1057 error = EXDEV; 1058 else 1059 error = EINVAL; 1060 vput(vp); 1061 return (error); 1062 } 1063 1064 /* 1065 * We only allow the filesystem to be reloaded if it 1066 * is currently mounted read-only. 1067 */ 1068 flag = mp->mnt_flag; 1069 if ((fsflags & MNT_RELOAD) != 0 && (flag & MNT_RDONLY) == 0) { 1070 vput(vp); 1071 return (EOPNOTSUPP); /* Needs translation */ 1072 } 1073 /* 1074 * Only privileged root, or (if MNT_USER is set) the user that 1075 * did the original mount is permitted to update it. 1076 */ 1077 error = vfs_suser(mp, td); 1078 if (error != 0) { 1079 vput(vp); 1080 return (error); 1081 } 1082 if (vfs_busy(mp, MBF_NOWAIT)) { 1083 vput(vp); 1084 return (EBUSY); 1085 } 1086 VI_LOCK(vp); 1087 if ((vp->v_iflag & VI_MOUNT) != 0 || vp->v_mountedhere != NULL) { 1088 VI_UNLOCK(vp); 1089 vfs_unbusy(mp); 1090 vput(vp); 1091 return (EBUSY); 1092 } 1093 vp->v_iflag |= VI_MOUNT; 1094 VI_UNLOCK(vp); 1095 VOP_UNLOCK(vp); 1096 1097 vfs_op_enter(mp); 1098 1099 MNT_ILOCK(mp); 1100 if ((mp->mnt_kern_flag & MNTK_UNMOUNT) != 0) { 1101 MNT_IUNLOCK(mp); 1102 error = EBUSY; 1103 goto end; 1104 } 1105 mp->mnt_flag &= ~MNT_UPDATEMASK; 1106 mp->mnt_flag |= fsflags & (MNT_RELOAD | MNT_FORCE | MNT_UPDATE | 1107 MNT_SNAPSHOT | MNT_ROOTFS | MNT_UPDATEMASK | MNT_RDONLY); 1108 if ((mp->mnt_flag & MNT_ASYNC) == 0) 1109 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1110 rootvp = vfs_cache_root_clear(mp); 1111 MNT_IUNLOCK(mp); 1112 if (rootvp != NULL) 1113 vrele(rootvp); 1114 mp->mnt_optnew = *optlist; 1115 vfs_mergeopts(mp->mnt_optnew, mp->mnt_opt); 1116 1117 /* 1118 * Mount the filesystem. 1119 * XXX The final recipients of VFS_MOUNT just overwrite the ndp they 1120 * get. No freeing of cn_pnbuf. 1121 */ 1122 error = VFS_MOUNT(mp); 1123 1124 export_error = 0; 1125 /* Process the export option. */ 1126 if (error == 0 && vfs_getopt(mp->mnt_optnew, "export", &bufp, 1127 &len) == 0) { 1128 /* Assume that there is only 1 ABI for each length. */ 1129 switch (len) { 1130 case (sizeof(struct oexport_args)): 1131 bzero(&export, sizeof(export)); 1132 /* FALLTHROUGH */ 1133 case (sizeof(export)): 1134 bcopy(bufp, &export, len); 1135 export_error = vfs_export(mp, &export); 1136 break; 1137 default: 1138 export_error = EINVAL; 1139 break; 1140 } 1141 } 1142 1143 MNT_ILOCK(mp); 1144 if (error == 0) { 1145 mp->mnt_flag &= ~(MNT_UPDATE | MNT_RELOAD | MNT_FORCE | 1146 MNT_SNAPSHOT); 1147 } else { 1148 /* 1149 * If we fail, restore old mount flags. MNT_QUOTA is special, 1150 * because it is not part of MNT_UPDATEMASK, but it could have 1151 * changed in the meantime if quotactl(2) was called. 1152 * All in all we want current value of MNT_QUOTA, not the old 1153 * one. 1154 */ 1155 mp->mnt_flag = (mp->mnt_flag & MNT_QUOTA) | (flag & ~MNT_QUOTA); 1156 } 1157 if ((mp->mnt_flag & MNT_ASYNC) != 0 && 1158 (mp->mnt_kern_flag & MNTK_NOASYNC) == 0) 1159 mp->mnt_kern_flag |= MNTK_ASYNC; 1160 else 1161 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1162 MNT_IUNLOCK(mp); 1163 1164 if (error != 0) 1165 goto end; 1166 1167 if (mp->mnt_opt != NULL) 1168 vfs_freeopts(mp->mnt_opt); 1169 mp->mnt_opt = mp->mnt_optnew; 1170 *optlist = NULL; 1171 (void)VFS_STATFS(mp, &mp->mnt_stat); 1172 /* 1173 * Prevent external consumers of mount options from reading 1174 * mnt_optnew. 1175 */ 1176 mp->mnt_optnew = NULL; 1177 1178 if ((mp->mnt_flag & MNT_RDONLY) == 0) 1179 vfs_allocate_syncvnode(mp); 1180 else 1181 vfs_deallocate_syncvnode(mp); 1182 end: 1183 vfs_op_exit(mp); 1184 vfs_unbusy(mp); 1185 VI_LOCK(vp); 1186 vp->v_iflag &= ~VI_MOUNT; 1187 VI_UNLOCK(vp); 1188 vrele(vp); 1189 return (error != 0 ? error : export_error); 1190 } 1191 1192 /* 1193 * vfs_domount(): actually attempt a filesystem mount. 1194 */ 1195 static int 1196 vfs_domount( 1197 struct thread *td, /* Calling thread. */ 1198 const char *fstype, /* Filesystem type. */ 1199 char *fspath, /* Mount path. */ 1200 uint64_t fsflags, /* Flags common to all filesystems. */ 1201 struct vfsoptlist **optlist /* Options local to the filesystem. */ 1202 ) 1203 { 1204 struct vfsconf *vfsp; 1205 struct nameidata nd; 1206 struct vnode *vp; 1207 char *pathbuf; 1208 int error; 1209 1210 /* 1211 * Be ultra-paranoid about making sure the type and fspath 1212 * variables will fit in our mp buffers, including the 1213 * terminating NUL. 1214 */ 1215 if (strlen(fstype) >= MFSNAMELEN || strlen(fspath) >= MNAMELEN) 1216 return (ENAMETOOLONG); 1217 1218 if (jailed(td->td_ucred) || usermount == 0) { 1219 if ((error = priv_check(td, PRIV_VFS_MOUNT)) != 0) 1220 return (error); 1221 } 1222 1223 /* 1224 * Do not allow NFS export or MNT_SUIDDIR by unprivileged users. 1225 */ 1226 if (fsflags & MNT_EXPORTED) { 1227 error = priv_check(td, PRIV_VFS_MOUNT_EXPORTED); 1228 if (error) 1229 return (error); 1230 } 1231 if (fsflags & MNT_SUIDDIR) { 1232 error = priv_check(td, PRIV_VFS_MOUNT_SUIDDIR); 1233 if (error) 1234 return (error); 1235 } 1236 /* 1237 * Silently enforce MNT_NOSUID and MNT_USER for unprivileged users. 1238 */ 1239 if ((fsflags & (MNT_NOSUID | MNT_USER)) != (MNT_NOSUID | MNT_USER)) { 1240 if (priv_check(td, PRIV_VFS_MOUNT_NONUSER) != 0) 1241 fsflags |= MNT_NOSUID | MNT_USER; 1242 } 1243 1244 /* Load KLDs before we lock the covered vnode to avoid reversals. */ 1245 vfsp = NULL; 1246 if ((fsflags & MNT_UPDATE) == 0) { 1247 /* Don't try to load KLDs if we're mounting the root. */ 1248 if (fsflags & MNT_ROOTFS) 1249 vfsp = vfs_byname(fstype); 1250 else 1251 vfsp = vfs_byname_kld(fstype, td, &error); 1252 if (vfsp == NULL) 1253 return (ENODEV); 1254 } 1255 1256 /* 1257 * Get vnode to be covered or mount point's vnode in case of MNT_UPDATE. 1258 */ 1259 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, 1260 UIO_SYSSPACE, fspath, td); 1261 error = namei(&nd); 1262 if (error != 0) 1263 return (error); 1264 NDFREE(&nd, NDF_ONLY_PNBUF); 1265 vp = nd.ni_vp; 1266 if ((fsflags & MNT_UPDATE) == 0) { 1267 if ((vp->v_vflag & VV_ROOT) != 0 && 1268 (fsflags & MNT_NOCOVER) != 0) { 1269 vput(vp); 1270 return (EBUSY); 1271 } 1272 pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK); 1273 strcpy(pathbuf, fspath); 1274 error = vn_path_to_global_path(td, vp, pathbuf, MNAMELEN); 1275 if (error == 0) { 1276 error = vfs_domount_first(td, vfsp, pathbuf, vp, 1277 fsflags, optlist); 1278 } 1279 free(pathbuf, M_TEMP); 1280 } else 1281 error = vfs_domount_update(td, vp, fsflags, optlist); 1282 1283 return (error); 1284 } 1285 1286 /* 1287 * Unmount a filesystem. 1288 * 1289 * Note: unmount takes a path to the vnode mounted on as argument, not 1290 * special file (as before). 1291 */ 1292 #ifndef _SYS_SYSPROTO_H_ 1293 struct unmount_args { 1294 char *path; 1295 int flags; 1296 }; 1297 #endif 1298 /* ARGSUSED */ 1299 int 1300 sys_unmount(struct thread *td, struct unmount_args *uap) 1301 { 1302 1303 return (kern_unmount(td, uap->path, uap->flags)); 1304 } 1305 1306 int 1307 kern_unmount(struct thread *td, const char *path, int flags) 1308 { 1309 struct nameidata nd; 1310 struct mount *mp; 1311 char *pathbuf; 1312 int error, id0, id1; 1313 1314 AUDIT_ARG_VALUE(flags); 1315 if (jailed(td->td_ucred) || usermount == 0) { 1316 error = priv_check(td, PRIV_VFS_UNMOUNT); 1317 if (error) 1318 return (error); 1319 } 1320 1321 pathbuf = malloc(MNAMELEN, M_TEMP, M_WAITOK); 1322 error = copyinstr(path, pathbuf, MNAMELEN, NULL); 1323 if (error) { 1324 free(pathbuf, M_TEMP); 1325 return (error); 1326 } 1327 if (flags & MNT_BYFSID) { 1328 AUDIT_ARG_TEXT(pathbuf); 1329 /* Decode the filesystem ID. */ 1330 if (sscanf(pathbuf, "FSID:%d:%d", &id0, &id1) != 2) { 1331 free(pathbuf, M_TEMP); 1332 return (EINVAL); 1333 } 1334 1335 mtx_lock(&mountlist_mtx); 1336 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1337 if (mp->mnt_stat.f_fsid.val[0] == id0 && 1338 mp->mnt_stat.f_fsid.val[1] == id1) { 1339 vfs_ref(mp); 1340 break; 1341 } 1342 } 1343 mtx_unlock(&mountlist_mtx); 1344 } else { 1345 /* 1346 * Try to find global path for path argument. 1347 */ 1348 NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1, 1349 UIO_SYSSPACE, pathbuf, td); 1350 if (namei(&nd) == 0) { 1351 NDFREE(&nd, NDF_ONLY_PNBUF); 1352 error = vn_path_to_global_path(td, nd.ni_vp, pathbuf, 1353 MNAMELEN); 1354 if (error == 0) 1355 vput(nd.ni_vp); 1356 } 1357 mtx_lock(&mountlist_mtx); 1358 TAILQ_FOREACH_REVERSE(mp, &mountlist, mntlist, mnt_list) { 1359 if (strcmp(mp->mnt_stat.f_mntonname, pathbuf) == 0) { 1360 vfs_ref(mp); 1361 break; 1362 } 1363 } 1364 mtx_unlock(&mountlist_mtx); 1365 } 1366 free(pathbuf, M_TEMP); 1367 if (mp == NULL) { 1368 /* 1369 * Previously we returned ENOENT for a nonexistent path and 1370 * EINVAL for a non-mountpoint. We cannot tell these apart 1371 * now, so in the !MNT_BYFSID case return the more likely 1372 * EINVAL for compatibility. 1373 */ 1374 return ((flags & MNT_BYFSID) ? ENOENT : EINVAL); 1375 } 1376 1377 /* 1378 * Don't allow unmounting the root filesystem. 1379 */ 1380 if (mp->mnt_flag & MNT_ROOTFS) { 1381 vfs_rel(mp); 1382 return (EINVAL); 1383 } 1384 error = dounmount(mp, flags, td); 1385 return (error); 1386 } 1387 1388 /* 1389 * Return error if any of the vnodes, ignoring the root vnode 1390 * and the syncer vnode, have non-zero usecount. 1391 * 1392 * This function is purely advisory - it can return false positives 1393 * and negatives. 1394 */ 1395 static int 1396 vfs_check_usecounts(struct mount *mp) 1397 { 1398 struct vnode *vp, *mvp; 1399 1400 MNT_VNODE_FOREACH_ALL(vp, mp, mvp) { 1401 if ((vp->v_vflag & VV_ROOT) == 0 && vp->v_type != VNON && 1402 vp->v_usecount != 0) { 1403 VI_UNLOCK(vp); 1404 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp); 1405 return (EBUSY); 1406 } 1407 VI_UNLOCK(vp); 1408 } 1409 1410 return (0); 1411 } 1412 1413 static void 1414 dounmount_cleanup(struct mount *mp, struct vnode *coveredvp, int mntkflags) 1415 { 1416 1417 mtx_assert(MNT_MTX(mp), MA_OWNED); 1418 mp->mnt_kern_flag &= ~mntkflags; 1419 if ((mp->mnt_kern_flag & MNTK_MWAIT) != 0) { 1420 mp->mnt_kern_flag &= ~MNTK_MWAIT; 1421 wakeup(mp); 1422 } 1423 vfs_op_exit_locked(mp); 1424 MNT_IUNLOCK(mp); 1425 if (coveredvp != NULL) { 1426 VOP_UNLOCK(coveredvp); 1427 vdrop(coveredvp); 1428 } 1429 vn_finished_write(mp); 1430 } 1431 1432 /* 1433 * There are various reference counters associated with the mount point. 1434 * Normally it is permitted to modify them without taking the mnt ilock, 1435 * but this behavior can be temporarily disabled if stable value is needed 1436 * or callers are expected to block (e.g. to not allow new users during 1437 * forced unmount). 1438 */ 1439 void 1440 vfs_op_enter(struct mount *mp) 1441 { 1442 int cpu; 1443 1444 MNT_ILOCK(mp); 1445 mp->mnt_vfs_ops++; 1446 if (mp->mnt_vfs_ops > 1) { 1447 MNT_IUNLOCK(mp); 1448 return; 1449 } 1450 vfs_op_barrier_wait(mp); 1451 CPU_FOREACH(cpu) { 1452 mp->mnt_ref += 1453 zpcpu_replace_cpu(mp->mnt_ref_pcpu, 0, cpu); 1454 mp->mnt_lockref += 1455 zpcpu_replace_cpu(mp->mnt_lockref_pcpu, 0, cpu); 1456 mp->mnt_writeopcount += 1457 zpcpu_replace_cpu(mp->mnt_writeopcount_pcpu, 0, cpu); 1458 } 1459 MNT_IUNLOCK(mp); 1460 vfs_assert_mount_counters(mp); 1461 } 1462 1463 void 1464 vfs_op_exit_locked(struct mount *mp) 1465 { 1466 1467 mtx_assert(MNT_MTX(mp), MA_OWNED); 1468 1469 if (mp->mnt_vfs_ops <= 0) 1470 panic("%s: invalid vfs_ops count %d for mp %p\n", 1471 __func__, mp->mnt_vfs_ops, mp); 1472 mp->mnt_vfs_ops--; 1473 } 1474 1475 void 1476 vfs_op_exit(struct mount *mp) 1477 { 1478 1479 MNT_ILOCK(mp); 1480 vfs_op_exit_locked(mp); 1481 MNT_IUNLOCK(mp); 1482 } 1483 1484 struct vfs_op_barrier_ipi { 1485 struct mount *mp; 1486 struct smp_rendezvous_cpus_retry_arg srcra; 1487 }; 1488 1489 static void 1490 vfs_op_action_func(void *arg) 1491 { 1492 struct vfs_op_barrier_ipi *vfsopipi; 1493 struct mount *mp; 1494 1495 vfsopipi = __containerof(arg, struct vfs_op_barrier_ipi, srcra); 1496 mp = vfsopipi->mp; 1497 1498 if (!vfs_op_thread_entered(mp)) 1499 smp_rendezvous_cpus_done(arg); 1500 } 1501 1502 static void 1503 vfs_op_wait_func(void *arg, int cpu) 1504 { 1505 struct vfs_op_barrier_ipi *vfsopipi; 1506 struct mount *mp; 1507 int *in_op; 1508 1509 vfsopipi = __containerof(arg, struct vfs_op_barrier_ipi, srcra); 1510 mp = vfsopipi->mp; 1511 1512 in_op = zpcpu_get_cpu(mp->mnt_thread_in_ops_pcpu, cpu); 1513 while (atomic_load_int(in_op)) 1514 cpu_spinwait(); 1515 } 1516 1517 void 1518 vfs_op_barrier_wait(struct mount *mp) 1519 { 1520 struct vfs_op_barrier_ipi vfsopipi; 1521 1522 vfsopipi.mp = mp; 1523 1524 smp_rendezvous_cpus_retry(all_cpus, 1525 smp_no_rendezvous_barrier, 1526 vfs_op_action_func, 1527 smp_no_rendezvous_barrier, 1528 vfs_op_wait_func, 1529 &vfsopipi.srcra); 1530 } 1531 1532 #ifdef DIAGNOSTIC 1533 void 1534 vfs_assert_mount_counters(struct mount *mp) 1535 { 1536 int cpu; 1537 1538 if (mp->mnt_vfs_ops == 0) 1539 return; 1540 1541 CPU_FOREACH(cpu) { 1542 if (*zpcpu_get_cpu(mp->mnt_ref_pcpu, cpu) != 0 || 1543 *zpcpu_get_cpu(mp->mnt_lockref_pcpu, cpu) != 0 || 1544 *zpcpu_get_cpu(mp->mnt_writeopcount_pcpu, cpu) != 0) 1545 vfs_dump_mount_counters(mp); 1546 } 1547 } 1548 1549 void 1550 vfs_dump_mount_counters(struct mount *mp) 1551 { 1552 int cpu, *count; 1553 int ref, lockref, writeopcount; 1554 1555 printf("%s: mp %p vfs_ops %d\n", __func__, mp, mp->mnt_vfs_ops); 1556 1557 printf(" ref : "); 1558 ref = mp->mnt_ref; 1559 CPU_FOREACH(cpu) { 1560 count = zpcpu_get_cpu(mp->mnt_ref_pcpu, cpu); 1561 printf("%d ", *count); 1562 ref += *count; 1563 } 1564 printf("\n"); 1565 printf(" lockref : "); 1566 lockref = mp->mnt_lockref; 1567 CPU_FOREACH(cpu) { 1568 count = zpcpu_get_cpu(mp->mnt_lockref_pcpu, cpu); 1569 printf("%d ", *count); 1570 lockref += *count; 1571 } 1572 printf("\n"); 1573 printf("writeopcount: "); 1574 writeopcount = mp->mnt_writeopcount; 1575 CPU_FOREACH(cpu) { 1576 count = zpcpu_get_cpu(mp->mnt_writeopcount_pcpu, cpu); 1577 printf("%d ", *count); 1578 writeopcount += *count; 1579 } 1580 printf("\n"); 1581 1582 printf("counter struct total\n"); 1583 printf("ref %-5d %-5d\n", mp->mnt_ref, ref); 1584 printf("lockref %-5d %-5d\n", mp->mnt_lockref, lockref); 1585 printf("writeopcount %-5d %-5d\n", mp->mnt_writeopcount, writeopcount); 1586 1587 panic("invalid counts on struct mount"); 1588 } 1589 #endif 1590 1591 int 1592 vfs_mount_fetch_counter(struct mount *mp, enum mount_counter which) 1593 { 1594 int *base, *pcpu; 1595 int cpu, sum; 1596 1597 switch (which) { 1598 case MNT_COUNT_REF: 1599 base = &mp->mnt_ref; 1600 pcpu = mp->mnt_ref_pcpu; 1601 break; 1602 case MNT_COUNT_LOCKREF: 1603 base = &mp->mnt_lockref; 1604 pcpu = mp->mnt_lockref_pcpu; 1605 break; 1606 case MNT_COUNT_WRITEOPCOUNT: 1607 base = &mp->mnt_writeopcount; 1608 pcpu = mp->mnt_writeopcount_pcpu; 1609 break; 1610 } 1611 1612 sum = *base; 1613 CPU_FOREACH(cpu) { 1614 sum += *zpcpu_get_cpu(pcpu, cpu); 1615 } 1616 return (sum); 1617 } 1618 1619 /* 1620 * Do the actual filesystem unmount. 1621 */ 1622 int 1623 dounmount(struct mount *mp, int flags, struct thread *td) 1624 { 1625 struct vnode *coveredvp, *rootvp; 1626 int error; 1627 uint64_t async_flag; 1628 int mnt_gen_r; 1629 1630 if ((coveredvp = mp->mnt_vnodecovered) != NULL) { 1631 mnt_gen_r = mp->mnt_gen; 1632 VI_LOCK(coveredvp); 1633 vholdl(coveredvp); 1634 vn_lock(coveredvp, LK_EXCLUSIVE | LK_INTERLOCK | LK_RETRY); 1635 /* 1636 * Check for mp being unmounted while waiting for the 1637 * covered vnode lock. 1638 */ 1639 if (coveredvp->v_mountedhere != mp || 1640 coveredvp->v_mountedhere->mnt_gen != mnt_gen_r) { 1641 VOP_UNLOCK(coveredvp); 1642 vdrop(coveredvp); 1643 vfs_rel(mp); 1644 return (EBUSY); 1645 } 1646 } 1647 1648 /* 1649 * Only privileged root, or (if MNT_USER is set) the user that did the 1650 * original mount is permitted to unmount this filesystem. 1651 */ 1652 error = vfs_suser(mp, td); 1653 if (error != 0) { 1654 if (coveredvp != NULL) { 1655 VOP_UNLOCK(coveredvp); 1656 vdrop(coveredvp); 1657 } 1658 vfs_rel(mp); 1659 return (error); 1660 } 1661 1662 vfs_op_enter(mp); 1663 1664 vn_start_write(NULL, &mp, V_WAIT | V_MNTREF); 1665 MNT_ILOCK(mp); 1666 if ((mp->mnt_kern_flag & MNTK_UNMOUNT) != 0 || 1667 (mp->mnt_flag & MNT_UPDATE) != 0 || 1668 !TAILQ_EMPTY(&mp->mnt_uppers)) { 1669 dounmount_cleanup(mp, coveredvp, 0); 1670 return (EBUSY); 1671 } 1672 mp->mnt_kern_flag |= MNTK_UNMOUNT; 1673 rootvp = vfs_cache_root_clear(mp); 1674 if (flags & MNT_NONBUSY) { 1675 MNT_IUNLOCK(mp); 1676 error = vfs_check_usecounts(mp); 1677 MNT_ILOCK(mp); 1678 if (error != 0) { 1679 dounmount_cleanup(mp, coveredvp, MNTK_UNMOUNT); 1680 if (rootvp != NULL) 1681 vrele(rootvp); 1682 return (error); 1683 } 1684 } 1685 /* Allow filesystems to detect that a forced unmount is in progress. */ 1686 if (flags & MNT_FORCE) { 1687 mp->mnt_kern_flag |= MNTK_UNMOUNTF; 1688 MNT_IUNLOCK(mp); 1689 /* 1690 * Must be done after setting MNTK_UNMOUNTF and before 1691 * waiting for mnt_lockref to become 0. 1692 */ 1693 VFS_PURGE(mp); 1694 MNT_ILOCK(mp); 1695 } 1696 error = 0; 1697 if (mp->mnt_lockref) { 1698 mp->mnt_kern_flag |= MNTK_DRAINING; 1699 error = msleep(&mp->mnt_lockref, MNT_MTX(mp), PVFS, 1700 "mount drain", 0); 1701 } 1702 MNT_IUNLOCK(mp); 1703 KASSERT(mp->mnt_lockref == 0, 1704 ("%s: invalid lock refcount in the drain path @ %s:%d", 1705 __func__, __FILE__, __LINE__)); 1706 KASSERT(error == 0, 1707 ("%s: invalid return value for msleep in the drain path @ %s:%d", 1708 __func__, __FILE__, __LINE__)); 1709 1710 if (rootvp != NULL) 1711 vrele(rootvp); 1712 1713 if (mp->mnt_flag & MNT_EXPUBLIC) 1714 vfs_setpublicfs(NULL, NULL, NULL); 1715 1716 /* 1717 * From now, we can claim that the use reference on the 1718 * coveredvp is ours, and the ref can be released only by 1719 * successfull unmount by us, or left for later unmount 1720 * attempt. The previously acquired hold reference is no 1721 * longer needed to protect the vnode from reuse. 1722 */ 1723 if (coveredvp != NULL) 1724 vdrop(coveredvp); 1725 1726 vfs_periodic(mp, MNT_WAIT); 1727 MNT_ILOCK(mp); 1728 async_flag = mp->mnt_flag & MNT_ASYNC; 1729 mp->mnt_flag &= ~MNT_ASYNC; 1730 mp->mnt_kern_flag &= ~MNTK_ASYNC; 1731 MNT_IUNLOCK(mp); 1732 cache_purgevfs(mp, false); /* remove cache entries for this file sys */ 1733 vfs_deallocate_syncvnode(mp); 1734 error = VFS_UNMOUNT(mp, flags); 1735 vn_finished_write(mp); 1736 /* 1737 * If we failed to flush the dirty blocks for this mount point, 1738 * undo all the cdir/rdir and rootvnode changes we made above. 1739 * Unless we failed to do so because the device is reporting that 1740 * it doesn't exist anymore. 1741 */ 1742 if (error && error != ENXIO) { 1743 MNT_ILOCK(mp); 1744 if ((mp->mnt_flag & MNT_RDONLY) == 0) { 1745 MNT_IUNLOCK(mp); 1746 vfs_allocate_syncvnode(mp); 1747 MNT_ILOCK(mp); 1748 } 1749 mp->mnt_kern_flag &= ~(MNTK_UNMOUNT | MNTK_UNMOUNTF); 1750 mp->mnt_flag |= async_flag; 1751 if ((mp->mnt_flag & MNT_ASYNC) != 0 && 1752 (mp->mnt_kern_flag & MNTK_NOASYNC) == 0) 1753 mp->mnt_kern_flag |= MNTK_ASYNC; 1754 if (mp->mnt_kern_flag & MNTK_MWAIT) { 1755 mp->mnt_kern_flag &= ~MNTK_MWAIT; 1756 wakeup(mp); 1757 } 1758 vfs_op_exit_locked(mp); 1759 MNT_IUNLOCK(mp); 1760 if (coveredvp) 1761 VOP_UNLOCK(coveredvp); 1762 return (error); 1763 } 1764 mtx_lock(&mountlist_mtx); 1765 TAILQ_REMOVE(&mountlist, mp, mnt_list); 1766 mtx_unlock(&mountlist_mtx); 1767 EVENTHANDLER_DIRECT_INVOKE(vfs_unmounted, mp, td); 1768 if (coveredvp != NULL) { 1769 coveredvp->v_mountedhere = NULL; 1770 VOP_UNLOCK(coveredvp); 1771 } 1772 vfs_event_signal(NULL, VQ_UNMOUNT, 0); 1773 if (rootvnode != NULL && mp == rootvnode->v_mount) { 1774 vrele(rootvnode); 1775 rootvnode = NULL; 1776 } 1777 if (mp == rootdevmp) 1778 rootdevmp = NULL; 1779 vfs_mount_destroy(mp); 1780 return (0); 1781 } 1782 1783 /* 1784 * Report errors during filesystem mounting. 1785 */ 1786 void 1787 vfs_mount_error(struct mount *mp, const char *fmt, ...) 1788 { 1789 struct vfsoptlist *moptlist = mp->mnt_optnew; 1790 va_list ap; 1791 int error, len; 1792 char *errmsg; 1793 1794 error = vfs_getopt(moptlist, "errmsg", (void **)&errmsg, &len); 1795 if (error || errmsg == NULL || len <= 0) 1796 return; 1797 1798 va_start(ap, fmt); 1799 vsnprintf(errmsg, (size_t)len, fmt, ap); 1800 va_end(ap); 1801 } 1802 1803 void 1804 vfs_opterror(struct vfsoptlist *opts, const char *fmt, ...) 1805 { 1806 va_list ap; 1807 int error, len; 1808 char *errmsg; 1809 1810 error = vfs_getopt(opts, "errmsg", (void **)&errmsg, &len); 1811 if (error || errmsg == NULL || len <= 0) 1812 return; 1813 1814 va_start(ap, fmt); 1815 vsnprintf(errmsg, (size_t)len, fmt, ap); 1816 va_end(ap); 1817 } 1818 1819 /* 1820 * --------------------------------------------------------------------- 1821 * Functions for querying mount options/arguments from filesystems. 1822 */ 1823 1824 /* 1825 * Check that no unknown options are given 1826 */ 1827 int 1828 vfs_filteropt(struct vfsoptlist *opts, const char **legal) 1829 { 1830 struct vfsopt *opt; 1831 char errmsg[255]; 1832 const char **t, *p, *q; 1833 int ret = 0; 1834 1835 TAILQ_FOREACH(opt, opts, link) { 1836 p = opt->name; 1837 q = NULL; 1838 if (p[0] == 'n' && p[1] == 'o') 1839 q = p + 2; 1840 for(t = global_opts; *t != NULL; t++) { 1841 if (strcmp(*t, p) == 0) 1842 break; 1843 if (q != NULL) { 1844 if (strcmp(*t, q) == 0) 1845 break; 1846 } 1847 } 1848 if (*t != NULL) 1849 continue; 1850 for(t = legal; *t != NULL; t++) { 1851 if (strcmp(*t, p) == 0) 1852 break; 1853 if (q != NULL) { 1854 if (strcmp(*t, q) == 0) 1855 break; 1856 } 1857 } 1858 if (*t != NULL) 1859 continue; 1860 snprintf(errmsg, sizeof(errmsg), 1861 "mount option <%s> is unknown", p); 1862 ret = EINVAL; 1863 } 1864 if (ret != 0) { 1865 TAILQ_FOREACH(opt, opts, link) { 1866 if (strcmp(opt->name, "errmsg") == 0) { 1867 strncpy((char *)opt->value, errmsg, opt->len); 1868 break; 1869 } 1870 } 1871 if (opt == NULL) 1872 printf("%s\n", errmsg); 1873 } 1874 return (ret); 1875 } 1876 1877 /* 1878 * Get a mount option by its name. 1879 * 1880 * Return 0 if the option was found, ENOENT otherwise. 1881 * If len is non-NULL it will be filled with the length 1882 * of the option. If buf is non-NULL, it will be filled 1883 * with the address of the option. 1884 */ 1885 int 1886 vfs_getopt(struct vfsoptlist *opts, const char *name, void **buf, int *len) 1887 { 1888 struct vfsopt *opt; 1889 1890 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 1891 1892 TAILQ_FOREACH(opt, opts, link) { 1893 if (strcmp(name, opt->name) == 0) { 1894 opt->seen = 1; 1895 if (len != NULL) 1896 *len = opt->len; 1897 if (buf != NULL) 1898 *buf = opt->value; 1899 return (0); 1900 } 1901 } 1902 return (ENOENT); 1903 } 1904 1905 int 1906 vfs_getopt_pos(struct vfsoptlist *opts, const char *name) 1907 { 1908 struct vfsopt *opt; 1909 1910 if (opts == NULL) 1911 return (-1); 1912 1913 TAILQ_FOREACH(opt, opts, link) { 1914 if (strcmp(name, opt->name) == 0) { 1915 opt->seen = 1; 1916 return (opt->pos); 1917 } 1918 } 1919 return (-1); 1920 } 1921 1922 int 1923 vfs_getopt_size(struct vfsoptlist *opts, const char *name, off_t *value) 1924 { 1925 char *opt_value, *vtp; 1926 quad_t iv; 1927 int error, opt_len; 1928 1929 error = vfs_getopt(opts, name, (void **)&opt_value, &opt_len); 1930 if (error != 0) 1931 return (error); 1932 if (opt_len == 0 || opt_value == NULL) 1933 return (EINVAL); 1934 if (opt_value[0] == '\0' || opt_value[opt_len - 1] != '\0') 1935 return (EINVAL); 1936 iv = strtoq(opt_value, &vtp, 0); 1937 if (vtp == opt_value || (vtp[0] != '\0' && vtp[1] != '\0')) 1938 return (EINVAL); 1939 if (iv < 0) 1940 return (EINVAL); 1941 switch (vtp[0]) { 1942 case 't': case 'T': 1943 iv *= 1024; 1944 /* FALLTHROUGH */ 1945 case 'g': case 'G': 1946 iv *= 1024; 1947 /* FALLTHROUGH */ 1948 case 'm': case 'M': 1949 iv *= 1024; 1950 /* FALLTHROUGH */ 1951 case 'k': case 'K': 1952 iv *= 1024; 1953 case '\0': 1954 break; 1955 default: 1956 return (EINVAL); 1957 } 1958 *value = iv; 1959 1960 return (0); 1961 } 1962 1963 char * 1964 vfs_getopts(struct vfsoptlist *opts, const char *name, int *error) 1965 { 1966 struct vfsopt *opt; 1967 1968 *error = 0; 1969 TAILQ_FOREACH(opt, opts, link) { 1970 if (strcmp(name, opt->name) != 0) 1971 continue; 1972 opt->seen = 1; 1973 if (opt->len == 0 || 1974 ((char *)opt->value)[opt->len - 1] != '\0') { 1975 *error = EINVAL; 1976 return (NULL); 1977 } 1978 return (opt->value); 1979 } 1980 *error = ENOENT; 1981 return (NULL); 1982 } 1983 1984 int 1985 vfs_flagopt(struct vfsoptlist *opts, const char *name, uint64_t *w, 1986 uint64_t val) 1987 { 1988 struct vfsopt *opt; 1989 1990 TAILQ_FOREACH(opt, opts, link) { 1991 if (strcmp(name, opt->name) == 0) { 1992 opt->seen = 1; 1993 if (w != NULL) 1994 *w |= val; 1995 return (1); 1996 } 1997 } 1998 if (w != NULL) 1999 *w &= ~val; 2000 return (0); 2001 } 2002 2003 int 2004 vfs_scanopt(struct vfsoptlist *opts, const char *name, const char *fmt, ...) 2005 { 2006 va_list ap; 2007 struct vfsopt *opt; 2008 int ret; 2009 2010 KASSERT(opts != NULL, ("vfs_getopt: caller passed 'opts' as NULL")); 2011 2012 TAILQ_FOREACH(opt, opts, link) { 2013 if (strcmp(name, opt->name) != 0) 2014 continue; 2015 opt->seen = 1; 2016 if (opt->len == 0 || opt->value == NULL) 2017 return (0); 2018 if (((char *)opt->value)[opt->len - 1] != '\0') 2019 return (0); 2020 va_start(ap, fmt); 2021 ret = vsscanf(opt->value, fmt, ap); 2022 va_end(ap); 2023 return (ret); 2024 } 2025 return (0); 2026 } 2027 2028 int 2029 vfs_setopt(struct vfsoptlist *opts, const char *name, void *value, int len) 2030 { 2031 struct vfsopt *opt; 2032 2033 TAILQ_FOREACH(opt, opts, link) { 2034 if (strcmp(name, opt->name) != 0) 2035 continue; 2036 opt->seen = 1; 2037 if (opt->value == NULL) 2038 opt->len = len; 2039 else { 2040 if (opt->len != len) 2041 return (EINVAL); 2042 bcopy(value, opt->value, len); 2043 } 2044 return (0); 2045 } 2046 return (ENOENT); 2047 } 2048 2049 int 2050 vfs_setopt_part(struct vfsoptlist *opts, const char *name, void *value, int len) 2051 { 2052 struct vfsopt *opt; 2053 2054 TAILQ_FOREACH(opt, opts, link) { 2055 if (strcmp(name, opt->name) != 0) 2056 continue; 2057 opt->seen = 1; 2058 if (opt->value == NULL) 2059 opt->len = len; 2060 else { 2061 if (opt->len < len) 2062 return (EINVAL); 2063 opt->len = len; 2064 bcopy(value, opt->value, len); 2065 } 2066 return (0); 2067 } 2068 return (ENOENT); 2069 } 2070 2071 int 2072 vfs_setopts(struct vfsoptlist *opts, const char *name, const char *value) 2073 { 2074 struct vfsopt *opt; 2075 2076 TAILQ_FOREACH(opt, opts, link) { 2077 if (strcmp(name, opt->name) != 0) 2078 continue; 2079 opt->seen = 1; 2080 if (opt->value == NULL) 2081 opt->len = strlen(value) + 1; 2082 else if (strlcpy(opt->value, value, opt->len) >= opt->len) 2083 return (EINVAL); 2084 return (0); 2085 } 2086 return (ENOENT); 2087 } 2088 2089 /* 2090 * Find and copy a mount option. 2091 * 2092 * The size of the buffer has to be specified 2093 * in len, if it is not the same length as the 2094 * mount option, EINVAL is returned. 2095 * Returns ENOENT if the option is not found. 2096 */ 2097 int 2098 vfs_copyopt(struct vfsoptlist *opts, const char *name, void *dest, int len) 2099 { 2100 struct vfsopt *opt; 2101 2102 KASSERT(opts != NULL, ("vfs_copyopt: caller passed 'opts' as NULL")); 2103 2104 TAILQ_FOREACH(opt, opts, link) { 2105 if (strcmp(name, opt->name) == 0) { 2106 opt->seen = 1; 2107 if (len != opt->len) 2108 return (EINVAL); 2109 bcopy(opt->value, dest, opt->len); 2110 return (0); 2111 } 2112 } 2113 return (ENOENT); 2114 } 2115 2116 int 2117 __vfs_statfs(struct mount *mp, struct statfs *sbp) 2118 { 2119 2120 /* 2121 * Filesystems only fill in part of the structure for updates, we 2122 * have to read the entirety first to get all content. 2123 */ 2124 memcpy(sbp, &mp->mnt_stat, sizeof(*sbp)); 2125 2126 /* 2127 * Set these in case the underlying filesystem fails to do so. 2128 */ 2129 sbp->f_version = STATFS_VERSION; 2130 sbp->f_namemax = NAME_MAX; 2131 sbp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK; 2132 2133 return (mp->mnt_op->vfs_statfs(mp, sbp)); 2134 } 2135 2136 void 2137 vfs_mountedfrom(struct mount *mp, const char *from) 2138 { 2139 2140 bzero(mp->mnt_stat.f_mntfromname, sizeof mp->mnt_stat.f_mntfromname); 2141 strlcpy(mp->mnt_stat.f_mntfromname, from, 2142 sizeof mp->mnt_stat.f_mntfromname); 2143 } 2144 2145 /* 2146 * --------------------------------------------------------------------- 2147 * This is the api for building mount args and mounting filesystems from 2148 * inside the kernel. 2149 * 2150 * The API works by accumulation of individual args. First error is 2151 * latched. 2152 * 2153 * XXX: should be documented in new manpage kernel_mount(9) 2154 */ 2155 2156 /* A memory allocation which must be freed when we are done */ 2157 struct mntaarg { 2158 SLIST_ENTRY(mntaarg) next; 2159 }; 2160 2161 /* The header for the mount arguments */ 2162 struct mntarg { 2163 struct iovec *v; 2164 int len; 2165 int error; 2166 SLIST_HEAD(, mntaarg) list; 2167 }; 2168 2169 /* 2170 * Add a boolean argument. 2171 * 2172 * flag is the boolean value. 2173 * name must start with "no". 2174 */ 2175 struct mntarg * 2176 mount_argb(struct mntarg *ma, int flag, const char *name) 2177 { 2178 2179 KASSERT(name[0] == 'n' && name[1] == 'o', 2180 ("mount_argb(...,%s): name must start with 'no'", name)); 2181 2182 return (mount_arg(ma, name + (flag ? 2 : 0), NULL, 0)); 2183 } 2184 2185 /* 2186 * Add an argument printf style 2187 */ 2188 struct mntarg * 2189 mount_argf(struct mntarg *ma, const char *name, const char *fmt, ...) 2190 { 2191 va_list ap; 2192 struct mntaarg *maa; 2193 struct sbuf *sb; 2194 int len; 2195 2196 if (ma == NULL) { 2197 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2198 SLIST_INIT(&ma->list); 2199 } 2200 if (ma->error) 2201 return (ma); 2202 2203 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 2204 M_MOUNT, M_WAITOK); 2205 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 2206 ma->v[ma->len].iov_len = strlen(name) + 1; 2207 ma->len++; 2208 2209 sb = sbuf_new_auto(); 2210 va_start(ap, fmt); 2211 sbuf_vprintf(sb, fmt, ap); 2212 va_end(ap); 2213 sbuf_finish(sb); 2214 len = sbuf_len(sb) + 1; 2215 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 2216 SLIST_INSERT_HEAD(&ma->list, maa, next); 2217 bcopy(sbuf_data(sb), maa + 1, len); 2218 sbuf_delete(sb); 2219 2220 ma->v[ma->len].iov_base = maa + 1; 2221 ma->v[ma->len].iov_len = len; 2222 ma->len++; 2223 2224 return (ma); 2225 } 2226 2227 /* 2228 * Add an argument which is a userland string. 2229 */ 2230 struct mntarg * 2231 mount_argsu(struct mntarg *ma, const char *name, const void *val, int len) 2232 { 2233 struct mntaarg *maa; 2234 char *tbuf; 2235 2236 if (val == NULL) 2237 return (ma); 2238 if (ma == NULL) { 2239 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2240 SLIST_INIT(&ma->list); 2241 } 2242 if (ma->error) 2243 return (ma); 2244 maa = malloc(sizeof *maa + len, M_MOUNT, M_WAITOK | M_ZERO); 2245 SLIST_INSERT_HEAD(&ma->list, maa, next); 2246 tbuf = (void *)(maa + 1); 2247 ma->error = copyinstr(val, tbuf, len, NULL); 2248 return (mount_arg(ma, name, tbuf, -1)); 2249 } 2250 2251 /* 2252 * Plain argument. 2253 * 2254 * If length is -1, treat value as a C string. 2255 */ 2256 struct mntarg * 2257 mount_arg(struct mntarg *ma, const char *name, const void *val, int len) 2258 { 2259 2260 if (ma == NULL) { 2261 ma = malloc(sizeof *ma, M_MOUNT, M_WAITOK | M_ZERO); 2262 SLIST_INIT(&ma->list); 2263 } 2264 if (ma->error) 2265 return (ma); 2266 2267 ma->v = realloc(ma->v, sizeof *ma->v * (ma->len + 2), 2268 M_MOUNT, M_WAITOK); 2269 ma->v[ma->len].iov_base = (void *)(uintptr_t)name; 2270 ma->v[ma->len].iov_len = strlen(name) + 1; 2271 ma->len++; 2272 2273 ma->v[ma->len].iov_base = (void *)(uintptr_t)val; 2274 if (len < 0) 2275 ma->v[ma->len].iov_len = strlen(val) + 1; 2276 else 2277 ma->v[ma->len].iov_len = len; 2278 ma->len++; 2279 return (ma); 2280 } 2281 2282 /* 2283 * Free a mntarg structure 2284 */ 2285 static void 2286 free_mntarg(struct mntarg *ma) 2287 { 2288 struct mntaarg *maa; 2289 2290 while (!SLIST_EMPTY(&ma->list)) { 2291 maa = SLIST_FIRST(&ma->list); 2292 SLIST_REMOVE_HEAD(&ma->list, next); 2293 free(maa, M_MOUNT); 2294 } 2295 free(ma->v, M_MOUNT); 2296 free(ma, M_MOUNT); 2297 } 2298 2299 /* 2300 * Mount a filesystem 2301 */ 2302 int 2303 kernel_mount(struct mntarg *ma, uint64_t flags) 2304 { 2305 struct uio auio; 2306 int error; 2307 2308 KASSERT(ma != NULL, ("kernel_mount NULL ma")); 2309 KASSERT(ma->v != NULL, ("kernel_mount NULL ma->v")); 2310 KASSERT(!(ma->len & 1), ("kernel_mount odd ma->len (%d)", ma->len)); 2311 2312 auio.uio_iov = ma->v; 2313 auio.uio_iovcnt = ma->len; 2314 auio.uio_segflg = UIO_SYSSPACE; 2315 2316 error = ma->error; 2317 if (!error) 2318 error = vfs_donmount(curthread, flags, &auio); 2319 free_mntarg(ma); 2320 return (error); 2321 } 2322 2323 /* 2324 * A printflike function to mount a filesystem. 2325 */ 2326 int 2327 kernel_vmount(int flags, ...) 2328 { 2329 struct mntarg *ma = NULL; 2330 va_list ap; 2331 const char *cp; 2332 const void *vp; 2333 int error; 2334 2335 va_start(ap, flags); 2336 for (;;) { 2337 cp = va_arg(ap, const char *); 2338 if (cp == NULL) 2339 break; 2340 vp = va_arg(ap, const void *); 2341 ma = mount_arg(ma, cp, vp, (vp != NULL ? -1 : 0)); 2342 } 2343 va_end(ap); 2344 2345 error = kernel_mount(ma, flags); 2346 return (error); 2347 } 2348 2349 /* 2350 * Convert the old export args format into new export args. 2351 * 2352 * The old export args struct does not have security flavors. Otherwise, the 2353 * structs are identical. The default security flavor 'sys' is applied when 2354 * the given args export the filesystem. 2355 */ 2356 void 2357 vfs_oexport_conv(const struct oexport_args *oexp, struct export_args *exp) 2358 { 2359 2360 bcopy(oexp, exp, sizeof(*oexp)); 2361 if (exp->ex_flags & MNT_EXPORTED) { 2362 exp->ex_numsecflavors = 1; 2363 exp->ex_secflavors[0] = AUTH_SYS; 2364 } else { 2365 exp->ex_numsecflavors = 0; 2366 } 2367 } 2368