1 /*- 2 * Copyright (c) 1982, 1986, 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)vfs_lookup.c 8.4 (Berkeley) 2/16/94 35 */ 36 37 #include <sys/cdefs.h> 38 __FBSDID("$FreeBSD$"); 39 40 #include "opt_capsicum.h" 41 #include "opt_kdtrace.h" 42 #include "opt_ktrace.h" 43 44 #include <sys/param.h> 45 #include <sys/systm.h> 46 #include <sys/kernel.h> 47 #include <sys/capability.h> 48 #include <sys/fcntl.h> 49 #include <sys/jail.h> 50 #include <sys/lock.h> 51 #include <sys/mutex.h> 52 #include <sys/namei.h> 53 #include <sys/vnode.h> 54 #include <sys/mount.h> 55 #include <sys/filedesc.h> 56 #include <sys/proc.h> 57 #include <sys/sdt.h> 58 #include <sys/syscallsubr.h> 59 #include <sys/sysctl.h> 60 #ifdef KTRACE 61 #include <sys/ktrace.h> 62 #endif 63 64 #include <security/audit/audit.h> 65 #include <security/mac/mac_framework.h> 66 67 #include <vm/uma.h> 68 69 #define NAMEI_DIAGNOSTIC 1 70 #undef NAMEI_DIAGNOSTIC 71 72 SDT_PROVIDER_DECLARE(vfs); 73 SDT_PROBE_DEFINE3(vfs, namei, lookup, entry, entry, "struct vnode *", "char *", 74 "unsigned long"); 75 SDT_PROBE_DEFINE2(vfs, namei, lookup, return, return, "int", "struct vnode *"); 76 77 /* 78 * Allocation zone for namei 79 */ 80 uma_zone_t namei_zone; 81 /* 82 * Placeholder vnode for mp traversal 83 */ 84 static struct vnode *vp_crossmp; 85 86 static void 87 nameiinit(void *dummy __unused) 88 { 89 90 namei_zone = uma_zcreate("NAMEI", MAXPATHLEN, NULL, NULL, NULL, NULL, 91 UMA_ALIGN_PTR, 0); 92 getnewvnode("crossmp", NULL, &dead_vnodeops, &vp_crossmp); 93 vn_lock(vp_crossmp, LK_EXCLUSIVE); 94 VN_LOCK_ASHARE(vp_crossmp); 95 VOP_UNLOCK(vp_crossmp, 0); 96 } 97 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_SECOND, nameiinit, NULL); 98 99 static int lookup_shared = 1; 100 SYSCTL_INT(_vfs, OID_AUTO, lookup_shared, CTLFLAG_RW, &lookup_shared, 0, 101 "Enables/Disables shared locks for path name translation"); 102 TUNABLE_INT("vfs.lookup_shared", &lookup_shared); 103 104 /* 105 * Convert a pathname into a pointer to a locked vnode. 106 * 107 * The FOLLOW flag is set when symbolic links are to be followed 108 * when they occur at the end of the name translation process. 109 * Symbolic links are always followed for all other pathname 110 * components other than the last. 111 * 112 * The segflg defines whether the name is to be copied from user 113 * space or kernel space. 114 * 115 * Overall outline of namei: 116 * 117 * copy in name 118 * get starting directory 119 * while (!done && !error) { 120 * call lookup to search path. 121 * if symbolic link, massage name in buffer and continue 122 * } 123 */ 124 int 125 namei(struct nameidata *ndp) 126 { 127 struct filedesc *fdp; /* pointer to file descriptor state */ 128 char *cp; /* pointer into pathname argument */ 129 struct vnode *dp; /* the directory we are searching */ 130 struct iovec aiov; /* uio for reading symbolic links */ 131 struct uio auio; 132 int error, linklen; 133 struct componentname *cnp = &ndp->ni_cnd; 134 struct thread *td = cnp->cn_thread; 135 struct proc *p = td->td_proc; 136 137 ndp->ni_cnd.cn_cred = ndp->ni_cnd.cn_thread->td_ucred; 138 KASSERT(cnp->cn_cred && p, ("namei: bad cred/proc")); 139 KASSERT((cnp->cn_nameiop & (~OPMASK)) == 0, 140 ("namei: nameiop contaminated with flags")); 141 KASSERT((cnp->cn_flags & OPMASK) == 0, 142 ("namei: flags contaminated with nameiops")); 143 if (!lookup_shared) 144 cnp->cn_flags &= ~LOCKSHARED; 145 fdp = p->p_fd; 146 147 /* We will set this ourselves if we need it. */ 148 cnp->cn_flags &= ~TRAILINGSLASH; 149 150 /* 151 * Get a buffer for the name to be translated, and copy the 152 * name into the buffer. 153 */ 154 if ((cnp->cn_flags & HASBUF) == 0) 155 cnp->cn_pnbuf = uma_zalloc(namei_zone, M_WAITOK); 156 if (ndp->ni_segflg == UIO_SYSSPACE) 157 error = copystr(ndp->ni_dirp, cnp->cn_pnbuf, 158 MAXPATHLEN, (size_t *)&ndp->ni_pathlen); 159 else 160 error = copyinstr(ndp->ni_dirp, cnp->cn_pnbuf, 161 MAXPATHLEN, (size_t *)&ndp->ni_pathlen); 162 163 /* 164 * Don't allow empty pathnames. 165 */ 166 if (!error && *cnp->cn_pnbuf == '\0') 167 error = ENOENT; 168 169 #ifdef CAPABILITY_MODE 170 /* 171 * In capability mode, lookups must be "strictly relative" (i.e. 172 * not an absolute path, and not containing '..' components) to 173 * a real file descriptor, not the pseudo-descriptor AT_FDCWD. 174 */ 175 if (error == 0 && IN_CAPABILITY_MODE(td) && 176 (cnp->cn_flags & NOCAPCHECK) == 0) { 177 ndp->ni_strictrelative = 1; 178 if (ndp->ni_dirfd == AT_FDCWD) { 179 #ifdef KTRACE 180 if (KTRPOINT(td, KTR_CAPFAIL)) 181 ktrcapfail(CAPFAIL_LOOKUP, 0, 0); 182 #endif 183 error = ECAPMODE; 184 } 185 } 186 #endif 187 if (error) { 188 uma_zfree(namei_zone, cnp->cn_pnbuf); 189 #ifdef DIAGNOSTIC 190 cnp->cn_pnbuf = NULL; 191 cnp->cn_nameptr = NULL; 192 #endif 193 ndp->ni_vp = NULL; 194 return (error); 195 } 196 ndp->ni_loopcnt = 0; 197 #ifdef KTRACE 198 if (KTRPOINT(td, KTR_NAMEI)) { 199 KASSERT(cnp->cn_thread == curthread, 200 ("namei not using curthread")); 201 ktrnamei(cnp->cn_pnbuf); 202 } 203 #endif 204 /* 205 * Get starting point for the translation. 206 */ 207 FILEDESC_SLOCK(fdp); 208 ndp->ni_rootdir = fdp->fd_rdir; 209 ndp->ni_topdir = fdp->fd_jdir; 210 211 /* 212 * If we are auditing the kernel pathname, save the user pathname. 213 */ 214 if (cnp->cn_flags & AUDITVNODE1) 215 AUDIT_ARG_UPATH1(td, ndp->ni_dirfd, cnp->cn_pnbuf); 216 if (cnp->cn_flags & AUDITVNODE2) 217 AUDIT_ARG_UPATH2(td, ndp->ni_dirfd, cnp->cn_pnbuf); 218 219 dp = NULL; 220 if (cnp->cn_pnbuf[0] != '/') { 221 if (ndp->ni_startdir != NULL) { 222 dp = ndp->ni_startdir; 223 error = 0; 224 } else if (ndp->ni_dirfd != AT_FDCWD) { 225 cap_rights_t rights; 226 227 rights = ndp->ni_rightsneeded; 228 cap_rights_set(&rights, CAP_LOOKUP); 229 230 if (cnp->cn_flags & AUDITVNODE1) 231 AUDIT_ARG_ATFD1(ndp->ni_dirfd); 232 if (cnp->cn_flags & AUDITVNODE2) 233 AUDIT_ARG_ATFD2(ndp->ni_dirfd); 234 error = fgetvp_rights(td, ndp->ni_dirfd, 235 &rights, &ndp->ni_filecaps, &dp); 236 #ifdef CAPABILITIES 237 /* 238 * If file descriptor doesn't have all rights, 239 * all lookups relative to it must also be 240 * strictly relative. 241 */ 242 CAP_ALL(&rights); 243 if (!cap_rights_contains(&ndp->ni_filecaps.fc_rights, 244 &rights) || 245 ndp->ni_filecaps.fc_fcntls != CAP_FCNTL_ALL || 246 ndp->ni_filecaps.fc_nioctls != -1) { 247 ndp->ni_strictrelative = 1; 248 } 249 #endif 250 } 251 if (error != 0 || dp != NULL) { 252 FILEDESC_SUNLOCK(fdp); 253 if (error == 0 && dp->v_type != VDIR) { 254 vrele(dp); 255 error = ENOTDIR; 256 } 257 } 258 if (error) { 259 uma_zfree(namei_zone, cnp->cn_pnbuf); 260 #ifdef DIAGNOSTIC 261 cnp->cn_pnbuf = NULL; 262 cnp->cn_nameptr = NULL; 263 #endif 264 return (error); 265 } 266 } 267 if (dp == NULL) { 268 dp = fdp->fd_cdir; 269 VREF(dp); 270 FILEDESC_SUNLOCK(fdp); 271 if (ndp->ni_startdir != NULL) 272 vrele(ndp->ni_startdir); 273 } 274 SDT_PROBE(vfs, namei, lookup, entry, dp, cnp->cn_pnbuf, 275 cnp->cn_flags, 0, 0); 276 for (;;) { 277 /* 278 * Check if root directory should replace current directory. 279 * Done at start of translation and after symbolic link. 280 */ 281 cnp->cn_nameptr = cnp->cn_pnbuf; 282 if (*(cnp->cn_nameptr) == '/') { 283 vrele(dp); 284 if (ndp->ni_strictrelative != 0) { 285 #ifdef KTRACE 286 if (KTRPOINT(curthread, KTR_CAPFAIL)) 287 ktrcapfail(CAPFAIL_LOOKUP, 0, 0); 288 #endif 289 return (ENOTCAPABLE); 290 } 291 while (*(cnp->cn_nameptr) == '/') { 292 cnp->cn_nameptr++; 293 ndp->ni_pathlen--; 294 } 295 dp = ndp->ni_rootdir; 296 VREF(dp); 297 } 298 ndp->ni_startdir = dp; 299 error = lookup(ndp); 300 if (error) { 301 uma_zfree(namei_zone, cnp->cn_pnbuf); 302 #ifdef DIAGNOSTIC 303 cnp->cn_pnbuf = NULL; 304 cnp->cn_nameptr = NULL; 305 #endif 306 SDT_PROBE(vfs, namei, lookup, return, error, NULL, 0, 307 0, 0); 308 return (error); 309 } 310 /* 311 * If not a symbolic link, we're done. 312 */ 313 if ((cnp->cn_flags & ISSYMLINK) == 0) { 314 if ((cnp->cn_flags & (SAVENAME | SAVESTART)) == 0) { 315 uma_zfree(namei_zone, cnp->cn_pnbuf); 316 #ifdef DIAGNOSTIC 317 cnp->cn_pnbuf = NULL; 318 cnp->cn_nameptr = NULL; 319 #endif 320 } else 321 cnp->cn_flags |= HASBUF; 322 323 SDT_PROBE(vfs, namei, lookup, return, 0, ndp->ni_vp, 324 0, 0, 0); 325 return (0); 326 } 327 if (ndp->ni_loopcnt++ >= MAXSYMLINKS) { 328 error = ELOOP; 329 break; 330 } 331 #ifdef MAC 332 if ((cnp->cn_flags & NOMACCHECK) == 0) { 333 error = mac_vnode_check_readlink(td->td_ucred, 334 ndp->ni_vp); 335 if (error) 336 break; 337 } 338 #endif 339 if (ndp->ni_pathlen > 1) 340 cp = uma_zalloc(namei_zone, M_WAITOK); 341 else 342 cp = cnp->cn_pnbuf; 343 aiov.iov_base = cp; 344 aiov.iov_len = MAXPATHLEN; 345 auio.uio_iov = &aiov; 346 auio.uio_iovcnt = 1; 347 auio.uio_offset = 0; 348 auio.uio_rw = UIO_READ; 349 auio.uio_segflg = UIO_SYSSPACE; 350 auio.uio_td = td; 351 auio.uio_resid = MAXPATHLEN; 352 error = VOP_READLINK(ndp->ni_vp, &auio, cnp->cn_cred); 353 if (error) { 354 if (ndp->ni_pathlen > 1) 355 uma_zfree(namei_zone, cp); 356 break; 357 } 358 linklen = MAXPATHLEN - auio.uio_resid; 359 if (linklen == 0) { 360 if (ndp->ni_pathlen > 1) 361 uma_zfree(namei_zone, cp); 362 error = ENOENT; 363 break; 364 } 365 if (linklen + ndp->ni_pathlen >= MAXPATHLEN) { 366 if (ndp->ni_pathlen > 1) 367 uma_zfree(namei_zone, cp); 368 error = ENAMETOOLONG; 369 break; 370 } 371 if (ndp->ni_pathlen > 1) { 372 bcopy(ndp->ni_next, cp + linklen, ndp->ni_pathlen); 373 uma_zfree(namei_zone, cnp->cn_pnbuf); 374 cnp->cn_pnbuf = cp; 375 } else 376 cnp->cn_pnbuf[linklen] = '\0'; 377 ndp->ni_pathlen += linklen; 378 vput(ndp->ni_vp); 379 dp = ndp->ni_dvp; 380 } 381 uma_zfree(namei_zone, cnp->cn_pnbuf); 382 #ifdef DIAGNOSTIC 383 cnp->cn_pnbuf = NULL; 384 cnp->cn_nameptr = NULL; 385 #endif 386 vput(ndp->ni_vp); 387 ndp->ni_vp = NULL; 388 vrele(ndp->ni_dvp); 389 SDT_PROBE(vfs, namei, lookup, return, error, NULL, 0, 0, 0); 390 return (error); 391 } 392 393 static int 394 compute_cn_lkflags(struct mount *mp, int lkflags, int cnflags) 395 { 396 397 if (mp == NULL || ((lkflags & LK_SHARED) && 398 (!(mp->mnt_kern_flag & MNTK_LOOKUP_SHARED) || 399 ((cnflags & ISDOTDOT) && 400 (mp->mnt_kern_flag & MNTK_LOOKUP_EXCL_DOTDOT))))) { 401 lkflags &= ~LK_SHARED; 402 lkflags |= LK_EXCLUSIVE; 403 } 404 return (lkflags); 405 } 406 407 static __inline int 408 needs_exclusive_leaf(struct mount *mp, int flags) 409 { 410 411 /* 412 * Intermediate nodes can use shared locks, we only need to 413 * force an exclusive lock for leaf nodes. 414 */ 415 if ((flags & (ISLASTCN | LOCKLEAF)) != (ISLASTCN | LOCKLEAF)) 416 return (0); 417 418 /* Always use exclusive locks if LOCKSHARED isn't set. */ 419 if (!(flags & LOCKSHARED)) 420 return (1); 421 422 /* 423 * For lookups during open(), if the mount point supports 424 * extended shared operations, then use a shared lock for the 425 * leaf node, otherwise use an exclusive lock. 426 */ 427 if (flags & ISOPEN) { 428 if (mp != NULL && 429 (mp->mnt_kern_flag & MNTK_EXTENDED_SHARED)) 430 return (0); 431 else 432 return (1); 433 } 434 435 /* 436 * Lookup requests outside of open() that specify LOCKSHARED 437 * only need a shared lock on the leaf vnode. 438 */ 439 return (0); 440 } 441 442 /* 443 * Search a pathname. 444 * This is a very central and rather complicated routine. 445 * 446 * The pathname is pointed to by ni_ptr and is of length ni_pathlen. 447 * The starting directory is taken from ni_startdir. The pathname is 448 * descended until done, or a symbolic link is encountered. The variable 449 * ni_more is clear if the path is completed; it is set to one if a 450 * symbolic link needing interpretation is encountered. 451 * 452 * The flag argument is LOOKUP, CREATE, RENAME, or DELETE depending on 453 * whether the name is to be looked up, created, renamed, or deleted. 454 * When CREATE, RENAME, or DELETE is specified, information usable in 455 * creating, renaming, or deleting a directory entry may be calculated. 456 * If flag has LOCKPARENT or'ed into it, the parent directory is returned 457 * locked. If flag has WANTPARENT or'ed into it, the parent directory is 458 * returned unlocked. Otherwise the parent directory is not returned. If 459 * the target of the pathname exists and LOCKLEAF is or'ed into the flag 460 * the target is returned locked, otherwise it is returned unlocked. 461 * When creating or renaming and LOCKPARENT is specified, the target may not 462 * be ".". When deleting and LOCKPARENT is specified, the target may be ".". 463 * 464 * Overall outline of lookup: 465 * 466 * dirloop: 467 * identify next component of name at ndp->ni_ptr 468 * handle degenerate case where name is null string 469 * if .. and crossing mount points and on mounted filesys, find parent 470 * call VOP_LOOKUP routine for next component name 471 * directory vnode returned in ni_dvp, unlocked unless LOCKPARENT set 472 * component vnode returned in ni_vp (if it exists), locked. 473 * if result vnode is mounted on and crossing mount points, 474 * find mounted on vnode 475 * if more components of name, do next level at dirloop 476 * return the answer in ni_vp, locked if LOCKLEAF set 477 * if LOCKPARENT set, return locked parent in ni_dvp 478 * if WANTPARENT set, return unlocked parent in ni_dvp 479 */ 480 int 481 lookup(struct nameidata *ndp) 482 { 483 char *cp; /* pointer into pathname argument */ 484 struct vnode *dp = 0; /* the directory we are searching */ 485 struct vnode *tdp; /* saved dp */ 486 struct mount *mp; /* mount table entry */ 487 struct prison *pr; 488 int docache; /* == 0 do not cache last component */ 489 int wantparent; /* 1 => wantparent or lockparent flag */ 490 int rdonly; /* lookup read-only flag bit */ 491 int error = 0; 492 int dpunlocked = 0; /* dp has already been unlocked */ 493 struct componentname *cnp = &ndp->ni_cnd; 494 int lkflags_save; 495 int ni_dvp_unlocked; 496 497 /* 498 * Setup: break out flag bits into variables. 499 */ 500 ni_dvp_unlocked = 0; 501 wantparent = cnp->cn_flags & (LOCKPARENT | WANTPARENT); 502 KASSERT(cnp->cn_nameiop == LOOKUP || wantparent, 503 ("CREATE, DELETE, RENAME require LOCKPARENT or WANTPARENT.")); 504 docache = (cnp->cn_flags & NOCACHE) ^ NOCACHE; 505 if (cnp->cn_nameiop == DELETE || 506 (wantparent && cnp->cn_nameiop != CREATE && 507 cnp->cn_nameiop != LOOKUP)) 508 docache = 0; 509 rdonly = cnp->cn_flags & RDONLY; 510 cnp->cn_flags &= ~ISSYMLINK; 511 ndp->ni_dvp = NULL; 512 /* 513 * We use shared locks until we hit the parent of the last cn then 514 * we adjust based on the requesting flags. 515 */ 516 if (lookup_shared) 517 cnp->cn_lkflags = LK_SHARED; 518 else 519 cnp->cn_lkflags = LK_EXCLUSIVE; 520 dp = ndp->ni_startdir; 521 ndp->ni_startdir = NULLVP; 522 vn_lock(dp, 523 compute_cn_lkflags(dp->v_mount, cnp->cn_lkflags | LK_RETRY, 524 cnp->cn_flags)); 525 526 dirloop: 527 /* 528 * Search a new directory. 529 * 530 * The last component of the filename is left accessible via 531 * cnp->cn_nameptr for callers that need the name. Callers needing 532 * the name set the SAVENAME flag. When done, they assume 533 * responsibility for freeing the pathname buffer. 534 */ 535 cnp->cn_consume = 0; 536 for (cp = cnp->cn_nameptr; *cp != 0 && *cp != '/'; cp++) 537 continue; 538 cnp->cn_namelen = cp - cnp->cn_nameptr; 539 if (cnp->cn_namelen > NAME_MAX) { 540 error = ENAMETOOLONG; 541 goto bad; 542 } 543 #ifdef NAMEI_DIAGNOSTIC 544 { char c = *cp; 545 *cp = '\0'; 546 printf("{%s}: ", cnp->cn_nameptr); 547 *cp = c; } 548 #endif 549 ndp->ni_pathlen -= cnp->cn_namelen; 550 ndp->ni_next = cp; 551 552 /* 553 * Replace multiple slashes by a single slash and trailing slashes 554 * by a null. This must be done before VOP_LOOKUP() because some 555 * fs's don't know about trailing slashes. Remember if there were 556 * trailing slashes to handle symlinks, existing non-directories 557 * and non-existing files that won't be directories specially later. 558 */ 559 while (*cp == '/' && (cp[1] == '/' || cp[1] == '\0')) { 560 cp++; 561 ndp->ni_pathlen--; 562 if (*cp == '\0') { 563 *ndp->ni_next = '\0'; 564 cnp->cn_flags |= TRAILINGSLASH; 565 } 566 } 567 ndp->ni_next = cp; 568 569 cnp->cn_flags |= MAKEENTRY; 570 if (*cp == '\0' && docache == 0) 571 cnp->cn_flags &= ~MAKEENTRY; 572 if (cnp->cn_namelen == 2 && 573 cnp->cn_nameptr[1] == '.' && cnp->cn_nameptr[0] == '.') 574 cnp->cn_flags |= ISDOTDOT; 575 else 576 cnp->cn_flags &= ~ISDOTDOT; 577 if (*ndp->ni_next == 0) 578 cnp->cn_flags |= ISLASTCN; 579 else 580 cnp->cn_flags &= ~ISLASTCN; 581 582 if ((cnp->cn_flags & ISLASTCN) != 0 && 583 cnp->cn_namelen == 1 && cnp->cn_nameptr[0] == '.' && 584 (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME)) { 585 error = EINVAL; 586 goto bad; 587 } 588 589 /* 590 * Check for degenerate name (e.g. / or "") 591 * which is a way of talking about a directory, 592 * e.g. like "/." or ".". 593 */ 594 if (cnp->cn_nameptr[0] == '\0') { 595 if (dp->v_type != VDIR) { 596 error = ENOTDIR; 597 goto bad; 598 } 599 if (cnp->cn_nameiop != LOOKUP) { 600 error = EISDIR; 601 goto bad; 602 } 603 if (wantparent) { 604 ndp->ni_dvp = dp; 605 VREF(dp); 606 } 607 ndp->ni_vp = dp; 608 609 if (cnp->cn_flags & AUDITVNODE1) 610 AUDIT_ARG_VNODE1(dp); 611 else if (cnp->cn_flags & AUDITVNODE2) 612 AUDIT_ARG_VNODE2(dp); 613 614 if (!(cnp->cn_flags & (LOCKPARENT | LOCKLEAF))) 615 VOP_UNLOCK(dp, 0); 616 /* XXX This should probably move to the top of function. */ 617 if (cnp->cn_flags & SAVESTART) 618 panic("lookup: SAVESTART"); 619 goto success; 620 } 621 622 /* 623 * Handle "..": five special cases. 624 * 0. If doing a capability lookup, return ENOTCAPABLE (this is a 625 * fairly conservative design choice, but it's the only one that we 626 * are satisfied guarantees the property we're looking for). 627 * 1. Return an error if this is the last component of 628 * the name and the operation is DELETE or RENAME. 629 * 2. If at root directory (e.g. after chroot) 630 * or at absolute root directory 631 * then ignore it so can't get out. 632 * 3. If this vnode is the root of a mounted 633 * filesystem, then replace it with the 634 * vnode which was mounted on so we take the 635 * .. in the other filesystem. 636 * 4. If the vnode is the top directory of 637 * the jail or chroot, don't let them out. 638 */ 639 if (cnp->cn_flags & ISDOTDOT) { 640 if (ndp->ni_strictrelative != 0) { 641 #ifdef KTRACE 642 if (KTRPOINT(curthread, KTR_CAPFAIL)) 643 ktrcapfail(CAPFAIL_LOOKUP, 0, 0); 644 #endif 645 error = ENOTCAPABLE; 646 goto bad; 647 } 648 if ((cnp->cn_flags & ISLASTCN) != 0 && 649 (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME)) { 650 error = EINVAL; 651 goto bad; 652 } 653 for (;;) { 654 for (pr = cnp->cn_cred->cr_prison; pr != NULL; 655 pr = pr->pr_parent) 656 if (dp == pr->pr_root) 657 break; 658 if (dp == ndp->ni_rootdir || 659 dp == ndp->ni_topdir || 660 dp == rootvnode || 661 pr != NULL || 662 ((dp->v_vflag & VV_ROOT) != 0 && 663 (cnp->cn_flags & NOCROSSMOUNT) != 0)) { 664 ndp->ni_dvp = dp; 665 ndp->ni_vp = dp; 666 VREF(dp); 667 goto nextname; 668 } 669 if ((dp->v_vflag & VV_ROOT) == 0) 670 break; 671 if (dp->v_iflag & VI_DOOMED) { /* forced unmount */ 672 error = ENOENT; 673 goto bad; 674 } 675 tdp = dp; 676 dp = dp->v_mount->mnt_vnodecovered; 677 VREF(dp); 678 vput(tdp); 679 vn_lock(dp, 680 compute_cn_lkflags(dp->v_mount, cnp->cn_lkflags | 681 LK_RETRY, ISDOTDOT)); 682 } 683 } 684 685 /* 686 * We now have a segment name to search for, and a directory to search. 687 */ 688 unionlookup: 689 #ifdef MAC 690 if ((cnp->cn_flags & NOMACCHECK) == 0) { 691 error = mac_vnode_check_lookup(cnp->cn_thread->td_ucred, dp, 692 cnp); 693 if (error) 694 goto bad; 695 } 696 #endif 697 ndp->ni_dvp = dp; 698 ndp->ni_vp = NULL; 699 ASSERT_VOP_LOCKED(dp, "lookup"); 700 /* 701 * If we have a shared lock we may need to upgrade the lock for the 702 * last operation. 703 */ 704 if (dp != vp_crossmp && 705 VOP_ISLOCKED(dp) == LK_SHARED && 706 (cnp->cn_flags & ISLASTCN) && (cnp->cn_flags & LOCKPARENT)) 707 vn_lock(dp, LK_UPGRADE|LK_RETRY); 708 if ((dp->v_iflag & VI_DOOMED) != 0) { 709 error = ENOENT; 710 goto bad; 711 } 712 /* 713 * If we're looking up the last component and we need an exclusive 714 * lock, adjust our lkflags. 715 */ 716 if (needs_exclusive_leaf(dp->v_mount, cnp->cn_flags)) 717 cnp->cn_lkflags = LK_EXCLUSIVE; 718 #ifdef NAMEI_DIAGNOSTIC 719 vprint("lookup in", dp); 720 #endif 721 lkflags_save = cnp->cn_lkflags; 722 cnp->cn_lkflags = compute_cn_lkflags(dp->v_mount, cnp->cn_lkflags, 723 cnp->cn_flags); 724 if ((error = VOP_LOOKUP(dp, &ndp->ni_vp, cnp)) != 0) { 725 cnp->cn_lkflags = lkflags_save; 726 KASSERT(ndp->ni_vp == NULL, ("leaf should be empty")); 727 #ifdef NAMEI_DIAGNOSTIC 728 printf("not found\n"); 729 #endif 730 if ((error == ENOENT) && 731 (dp->v_vflag & VV_ROOT) && (dp->v_mount != NULL) && 732 (dp->v_mount->mnt_flag & MNT_UNION)) { 733 tdp = dp; 734 dp = dp->v_mount->mnt_vnodecovered; 735 VREF(dp); 736 vput(tdp); 737 vn_lock(dp, 738 compute_cn_lkflags(dp->v_mount, cnp->cn_lkflags | 739 LK_RETRY, cnp->cn_flags)); 740 goto unionlookup; 741 } 742 743 if (error != EJUSTRETURN) 744 goto bad; 745 /* 746 * At this point, we know we're at the end of the 747 * pathname. If creating / renaming, we can consider 748 * allowing the file or directory to be created / renamed, 749 * provided we're not on a read-only filesystem. 750 */ 751 if (rdonly) { 752 error = EROFS; 753 goto bad; 754 } 755 /* trailing slash only allowed for directories */ 756 if ((cnp->cn_flags & TRAILINGSLASH) && 757 !(cnp->cn_flags & WILLBEDIR)) { 758 error = ENOENT; 759 goto bad; 760 } 761 if ((cnp->cn_flags & LOCKPARENT) == 0) 762 VOP_UNLOCK(dp, 0); 763 /* 764 * We return with ni_vp NULL to indicate that the entry 765 * doesn't currently exist, leaving a pointer to the 766 * (possibly locked) directory vnode in ndp->ni_dvp. 767 */ 768 if (cnp->cn_flags & SAVESTART) { 769 ndp->ni_startdir = ndp->ni_dvp; 770 VREF(ndp->ni_startdir); 771 } 772 goto success; 773 } else 774 cnp->cn_lkflags = lkflags_save; 775 #ifdef NAMEI_DIAGNOSTIC 776 printf("found\n"); 777 #endif 778 /* 779 * Take into account any additional components consumed by 780 * the underlying filesystem. 781 */ 782 if (cnp->cn_consume > 0) { 783 cnp->cn_nameptr += cnp->cn_consume; 784 ndp->ni_next += cnp->cn_consume; 785 ndp->ni_pathlen -= cnp->cn_consume; 786 cnp->cn_consume = 0; 787 } 788 789 dp = ndp->ni_vp; 790 791 /* 792 * Check to see if the vnode has been mounted on; 793 * if so find the root of the mounted filesystem. 794 */ 795 while (dp->v_type == VDIR && (mp = dp->v_mountedhere) && 796 (cnp->cn_flags & NOCROSSMOUNT) == 0) { 797 if (vfs_busy(mp, 0)) 798 continue; 799 vput(dp); 800 if (dp != ndp->ni_dvp) 801 vput(ndp->ni_dvp); 802 else 803 vrele(ndp->ni_dvp); 804 vref(vp_crossmp); 805 ndp->ni_dvp = vp_crossmp; 806 error = VFS_ROOT(mp, compute_cn_lkflags(mp, cnp->cn_lkflags, 807 cnp->cn_flags), &tdp); 808 vfs_unbusy(mp); 809 if (vn_lock(vp_crossmp, LK_SHARED | LK_NOWAIT)) 810 panic("vp_crossmp exclusively locked or reclaimed"); 811 if (error) { 812 dpunlocked = 1; 813 goto bad2; 814 } 815 ndp->ni_vp = dp = tdp; 816 } 817 818 /* 819 * Check for symbolic link 820 */ 821 if ((dp->v_type == VLNK) && 822 ((cnp->cn_flags & FOLLOW) || (cnp->cn_flags & TRAILINGSLASH) || 823 *ndp->ni_next == '/')) { 824 cnp->cn_flags |= ISSYMLINK; 825 if (dp->v_iflag & VI_DOOMED) { 826 /* 827 * We can't know whether the directory was mounted with 828 * NOSYMFOLLOW, so we can't follow safely. 829 */ 830 error = ENOENT; 831 goto bad2; 832 } 833 if (dp->v_mount->mnt_flag & MNT_NOSYMFOLLOW) { 834 error = EACCES; 835 goto bad2; 836 } 837 /* 838 * Symlink code always expects an unlocked dvp. 839 */ 840 if (ndp->ni_dvp != ndp->ni_vp) { 841 VOP_UNLOCK(ndp->ni_dvp, 0); 842 ni_dvp_unlocked = 1; 843 } 844 goto success; 845 } 846 847 nextname: 848 /* 849 * Not a symbolic link that we will follow. Continue with the 850 * next component if there is any; otherwise, we're done. 851 */ 852 KASSERT((cnp->cn_flags & ISLASTCN) || *ndp->ni_next == '/', 853 ("lookup: invalid path state.")); 854 if (*ndp->ni_next == '/') { 855 cnp->cn_nameptr = ndp->ni_next; 856 while (*cnp->cn_nameptr == '/') { 857 cnp->cn_nameptr++; 858 ndp->ni_pathlen--; 859 } 860 if (ndp->ni_dvp != dp) 861 vput(ndp->ni_dvp); 862 else 863 vrele(ndp->ni_dvp); 864 goto dirloop; 865 } 866 /* 867 * If we're processing a path with a trailing slash, 868 * check that the end result is a directory. 869 */ 870 if ((cnp->cn_flags & TRAILINGSLASH) && dp->v_type != VDIR) { 871 error = ENOTDIR; 872 goto bad2; 873 } 874 /* 875 * Disallow directory write attempts on read-only filesystems. 876 */ 877 if (rdonly && 878 (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME)) { 879 error = EROFS; 880 goto bad2; 881 } 882 if (cnp->cn_flags & SAVESTART) { 883 ndp->ni_startdir = ndp->ni_dvp; 884 VREF(ndp->ni_startdir); 885 } 886 if (!wantparent) { 887 ni_dvp_unlocked = 2; 888 if (ndp->ni_dvp != dp) 889 vput(ndp->ni_dvp); 890 else 891 vrele(ndp->ni_dvp); 892 } else if ((cnp->cn_flags & LOCKPARENT) == 0 && ndp->ni_dvp != dp) { 893 VOP_UNLOCK(ndp->ni_dvp, 0); 894 ni_dvp_unlocked = 1; 895 } 896 897 if (cnp->cn_flags & AUDITVNODE1) 898 AUDIT_ARG_VNODE1(dp); 899 else if (cnp->cn_flags & AUDITVNODE2) 900 AUDIT_ARG_VNODE2(dp); 901 902 if ((cnp->cn_flags & LOCKLEAF) == 0) 903 VOP_UNLOCK(dp, 0); 904 success: 905 /* 906 * Because of lookup_shared we may have the vnode shared locked, but 907 * the caller may want it to be exclusively locked. 908 */ 909 if (needs_exclusive_leaf(dp->v_mount, cnp->cn_flags) && 910 VOP_ISLOCKED(dp) != LK_EXCLUSIVE) { 911 vn_lock(dp, LK_UPGRADE | LK_RETRY); 912 if (dp->v_iflag & VI_DOOMED) { 913 error = ENOENT; 914 goto bad2; 915 } 916 } 917 return (0); 918 919 bad2: 920 if (ni_dvp_unlocked != 2) { 921 if (dp != ndp->ni_dvp && !ni_dvp_unlocked) 922 vput(ndp->ni_dvp); 923 else 924 vrele(ndp->ni_dvp); 925 } 926 bad: 927 if (!dpunlocked) 928 vput(dp); 929 ndp->ni_vp = NULL; 930 return (error); 931 } 932 933 /* 934 * relookup - lookup a path name component 935 * Used by lookup to re-acquire things. 936 */ 937 int 938 relookup(struct vnode *dvp, struct vnode **vpp, struct componentname *cnp) 939 { 940 struct vnode *dp = 0; /* the directory we are searching */ 941 int wantparent; /* 1 => wantparent or lockparent flag */ 942 int rdonly; /* lookup read-only flag bit */ 943 int error = 0; 944 945 KASSERT(cnp->cn_flags & ISLASTCN, 946 ("relookup: Not given last component.")); 947 /* 948 * Setup: break out flag bits into variables. 949 */ 950 wantparent = cnp->cn_flags & (LOCKPARENT|WANTPARENT); 951 KASSERT(wantparent, ("relookup: parent not wanted.")); 952 rdonly = cnp->cn_flags & RDONLY; 953 cnp->cn_flags &= ~ISSYMLINK; 954 dp = dvp; 955 cnp->cn_lkflags = LK_EXCLUSIVE; 956 vn_lock(dp, LK_EXCLUSIVE | LK_RETRY); 957 958 /* 959 * Search a new directory. 960 * 961 * The last component of the filename is left accessible via 962 * cnp->cn_nameptr for callers that need the name. Callers needing 963 * the name set the SAVENAME flag. When done, they assume 964 * responsibility for freeing the pathname buffer. 965 */ 966 #ifdef NAMEI_DIAGNOSTIC 967 printf("{%s}: ", cnp->cn_nameptr); 968 #endif 969 970 /* 971 * Check for "" which represents the root directory after slash 972 * removal. 973 */ 974 if (cnp->cn_nameptr[0] == '\0') { 975 /* 976 * Support only LOOKUP for "/" because lookup() 977 * can't succeed for CREATE, DELETE and RENAME. 978 */ 979 KASSERT(cnp->cn_nameiop == LOOKUP, ("nameiop must be LOOKUP")); 980 KASSERT(dp->v_type == VDIR, ("dp is not a directory")); 981 982 if (!(cnp->cn_flags & LOCKLEAF)) 983 VOP_UNLOCK(dp, 0); 984 *vpp = dp; 985 /* XXX This should probably move to the top of function. */ 986 if (cnp->cn_flags & SAVESTART) 987 panic("lookup: SAVESTART"); 988 return (0); 989 } 990 991 if (cnp->cn_flags & ISDOTDOT) 992 panic ("relookup: lookup on dot-dot"); 993 994 /* 995 * We now have a segment name to search for, and a directory to search. 996 */ 997 #ifdef NAMEI_DIAGNOSTIC 998 vprint("search in:", dp); 999 #endif 1000 if ((error = VOP_LOOKUP(dp, vpp, cnp)) != 0) { 1001 KASSERT(*vpp == NULL, ("leaf should be empty")); 1002 if (error != EJUSTRETURN) 1003 goto bad; 1004 /* 1005 * If creating and at end of pathname, then can consider 1006 * allowing file to be created. 1007 */ 1008 if (rdonly) { 1009 error = EROFS; 1010 goto bad; 1011 } 1012 /* ASSERT(dvp == ndp->ni_startdir) */ 1013 if (cnp->cn_flags & SAVESTART) 1014 VREF(dvp); 1015 if ((cnp->cn_flags & LOCKPARENT) == 0) 1016 VOP_UNLOCK(dp, 0); 1017 /* 1018 * We return with ni_vp NULL to indicate that the entry 1019 * doesn't currently exist, leaving a pointer to the 1020 * (possibly locked) directory vnode in ndp->ni_dvp. 1021 */ 1022 return (0); 1023 } 1024 1025 dp = *vpp; 1026 1027 /* 1028 * Disallow directory write attempts on read-only filesystems. 1029 */ 1030 if (rdonly && 1031 (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME)) { 1032 if (dvp == dp) 1033 vrele(dvp); 1034 else 1035 vput(dvp); 1036 error = EROFS; 1037 goto bad; 1038 } 1039 /* 1040 * Set the parent lock/ref state to the requested state. 1041 */ 1042 if ((cnp->cn_flags & LOCKPARENT) == 0 && dvp != dp) { 1043 if (wantparent) 1044 VOP_UNLOCK(dvp, 0); 1045 else 1046 vput(dvp); 1047 } else if (!wantparent) 1048 vrele(dvp); 1049 /* 1050 * Check for symbolic link 1051 */ 1052 KASSERT(dp->v_type != VLNK || !(cnp->cn_flags & FOLLOW), 1053 ("relookup: symlink found.\n")); 1054 1055 /* ASSERT(dvp == ndp->ni_startdir) */ 1056 if (cnp->cn_flags & SAVESTART) 1057 VREF(dvp); 1058 1059 if ((cnp->cn_flags & LOCKLEAF) == 0) 1060 VOP_UNLOCK(dp, 0); 1061 return (0); 1062 bad: 1063 vput(dp); 1064 *vpp = NULL; 1065 return (error); 1066 } 1067 1068 void 1069 NDINIT_ALL(struct nameidata *ndp, u_long op, u_long flags, enum uio_seg segflg, 1070 const char *namep, int dirfd, struct vnode *startdir, cap_rights_t *rightsp, 1071 struct thread *td) 1072 { 1073 1074 ndp->ni_cnd.cn_nameiop = op; 1075 ndp->ni_cnd.cn_flags = flags; 1076 ndp->ni_segflg = segflg; 1077 ndp->ni_dirp = namep; 1078 ndp->ni_dirfd = dirfd; 1079 ndp->ni_startdir = startdir; 1080 ndp->ni_strictrelative = 0; 1081 if (rightsp != NULL) 1082 ndp->ni_rightsneeded = *rightsp; 1083 else 1084 cap_rights_init(&ndp->ni_rightsneeded); 1085 filecaps_init(&ndp->ni_filecaps); 1086 ndp->ni_cnd.cn_thread = td; 1087 } 1088 1089 /* 1090 * Free data allocated by namei(); see namei(9) for details. 1091 */ 1092 void 1093 NDFREE(struct nameidata *ndp, const u_int flags) 1094 { 1095 int unlock_dvp; 1096 int unlock_vp; 1097 1098 unlock_dvp = 0; 1099 unlock_vp = 0; 1100 1101 if (!(flags & NDF_NO_FREE_PNBUF) && 1102 (ndp->ni_cnd.cn_flags & HASBUF)) { 1103 uma_zfree(namei_zone, ndp->ni_cnd.cn_pnbuf); 1104 ndp->ni_cnd.cn_flags &= ~HASBUF; 1105 } 1106 if (!(flags & NDF_NO_VP_UNLOCK) && 1107 (ndp->ni_cnd.cn_flags & LOCKLEAF) && ndp->ni_vp) 1108 unlock_vp = 1; 1109 if (!(flags & NDF_NO_VP_RELE) && ndp->ni_vp) { 1110 if (unlock_vp) { 1111 vput(ndp->ni_vp); 1112 unlock_vp = 0; 1113 } else 1114 vrele(ndp->ni_vp); 1115 ndp->ni_vp = NULL; 1116 } 1117 if (unlock_vp) 1118 VOP_UNLOCK(ndp->ni_vp, 0); 1119 if (!(flags & NDF_NO_DVP_UNLOCK) && 1120 (ndp->ni_cnd.cn_flags & LOCKPARENT) && 1121 ndp->ni_dvp != ndp->ni_vp) 1122 unlock_dvp = 1; 1123 if (!(flags & NDF_NO_DVP_RELE) && 1124 (ndp->ni_cnd.cn_flags & (LOCKPARENT|WANTPARENT))) { 1125 if (unlock_dvp) { 1126 vput(ndp->ni_dvp); 1127 unlock_dvp = 0; 1128 } else 1129 vrele(ndp->ni_dvp); 1130 ndp->ni_dvp = NULL; 1131 } 1132 if (unlock_dvp) 1133 VOP_UNLOCK(ndp->ni_dvp, 0); 1134 if (!(flags & NDF_NO_STARTDIR_RELE) && 1135 (ndp->ni_cnd.cn_flags & SAVESTART)) { 1136 vrele(ndp->ni_startdir); 1137 ndp->ni_startdir = NULL; 1138 } 1139 } 1140 1141 /* 1142 * Determine if there is a suitable alternate filename under the specified 1143 * prefix for the specified path. If the create flag is set, then the 1144 * alternate prefix will be used so long as the parent directory exists. 1145 * This is used by the various compatiblity ABIs so that Linux binaries prefer 1146 * files under /compat/linux for example. The chosen path (whether under 1147 * the prefix or under /) is returned in a kernel malloc'd buffer pointed 1148 * to by pathbuf. The caller is responsible for free'ing the buffer from 1149 * the M_TEMP bucket if one is returned. 1150 */ 1151 int 1152 kern_alternate_path(struct thread *td, const char *prefix, const char *path, 1153 enum uio_seg pathseg, char **pathbuf, int create, int dirfd) 1154 { 1155 struct nameidata nd, ndroot; 1156 char *ptr, *buf, *cp; 1157 size_t len, sz; 1158 int error; 1159 1160 buf = (char *) malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1161 *pathbuf = buf; 1162 1163 /* Copy the prefix into the new pathname as a starting point. */ 1164 len = strlcpy(buf, prefix, MAXPATHLEN); 1165 if (len >= MAXPATHLEN) { 1166 *pathbuf = NULL; 1167 free(buf, M_TEMP); 1168 return (EINVAL); 1169 } 1170 sz = MAXPATHLEN - len; 1171 ptr = buf + len; 1172 1173 /* Append the filename to the prefix. */ 1174 if (pathseg == UIO_SYSSPACE) 1175 error = copystr(path, ptr, sz, &len); 1176 else 1177 error = copyinstr(path, ptr, sz, &len); 1178 1179 if (error) { 1180 *pathbuf = NULL; 1181 free(buf, M_TEMP); 1182 return (error); 1183 } 1184 1185 /* Only use a prefix with absolute pathnames. */ 1186 if (*ptr != '/') { 1187 error = EINVAL; 1188 goto keeporig; 1189 } 1190 1191 if (dirfd != AT_FDCWD) { 1192 /* 1193 * We want the original because the "prefix" is 1194 * included in the already opened dirfd. 1195 */ 1196 bcopy(ptr, buf, len); 1197 return (0); 1198 } 1199 1200 /* 1201 * We know that there is a / somewhere in this pathname. 1202 * Search backwards for it, to find the file's parent dir 1203 * to see if it exists in the alternate tree. If it does, 1204 * and we want to create a file (cflag is set). We don't 1205 * need to worry about the root comparison in this case. 1206 */ 1207 1208 if (create) { 1209 for (cp = &ptr[len] - 1; *cp != '/'; cp--); 1210 *cp = '\0'; 1211 1212 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, buf, td); 1213 error = namei(&nd); 1214 *cp = '/'; 1215 if (error != 0) 1216 goto keeporig; 1217 } else { 1218 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, buf, td); 1219 1220 error = namei(&nd); 1221 if (error != 0) 1222 goto keeporig; 1223 1224 /* 1225 * We now compare the vnode of the prefix to the one 1226 * vnode asked. If they resolve to be the same, then we 1227 * ignore the match so that the real root gets used. 1228 * This avoids the problem of traversing "../.." to find the 1229 * root directory and never finding it, because "/" resolves 1230 * to the emulation root directory. This is expensive :-( 1231 */ 1232 NDINIT(&ndroot, LOOKUP, FOLLOW, UIO_SYSSPACE, prefix, 1233 td); 1234 1235 /* We shouldn't ever get an error from this namei(). */ 1236 error = namei(&ndroot); 1237 if (error == 0) { 1238 if (nd.ni_vp == ndroot.ni_vp) 1239 error = ENOENT; 1240 1241 NDFREE(&ndroot, NDF_ONLY_PNBUF); 1242 vrele(ndroot.ni_vp); 1243 } 1244 } 1245 1246 NDFREE(&nd, NDF_ONLY_PNBUF); 1247 vrele(nd.ni_vp); 1248 1249 keeporig: 1250 /* If there was an error, use the original path name. */ 1251 if (error) 1252 bcopy(ptr, buf, len); 1253 return (error); 1254 } 1255