FreeBSD/Linux Kernel Cross Reference
sys/kern/vfs_lookup.c
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: releng/11.0/sys/kern/vfs_lookup.c 298819 2016-04-29 22:15:33Z pfg $");
39
40 #include "opt_capsicum.h"
41 #include "opt_ktrace.h"
42
43 #include <sys/param.h>
44 #include <sys/systm.h>
45 #include <sys/kernel.h>
46 #include <sys/capsicum.h>
47 #include <sys/fcntl.h>
48 #include <sys/jail.h>
49 #include <sys/lock.h>
50 #include <sys/mutex.h>
51 #include <sys/namei.h>
52 #include <sys/vnode.h>
53 #include <sys/mount.h>
54 #include <sys/filedesc.h>
55 #include <sys/proc.h>
56 #include <sys/sdt.h>
57 #include <sys/syscallsubr.h>
58 #include <sys/sysctl.h>
59 #ifdef KTRACE
60 #include <sys/ktrace.h>
61 #endif
62
63 #include <security/audit/audit.h>
64 #include <security/mac/mac_framework.h>
65
66 #include <vm/uma.h>
67
68 #define NAMEI_DIAGNOSTIC 1
69 #undef NAMEI_DIAGNOSTIC
70
71 SDT_PROVIDER_DECLARE(vfs);
72 SDT_PROBE_DEFINE3(vfs, namei, lookup, entry, "struct vnode *", "char *",
73 "unsigned long");
74 SDT_PROBE_DEFINE2(vfs, namei, lookup, return, "int", "struct vnode *");
75
76 /*
77 * Allocation zone for namei
78 */
79 uma_zone_t namei_zone;
80 /*
81 * Placeholder vnode for mp traversal
82 */
83 static struct vnode *vp_crossmp;
84
85 static void
86 nameiinit(void *dummy __unused)
87 {
88
89 namei_zone = uma_zcreate("NAMEI", MAXPATHLEN, NULL, NULL, NULL, NULL,
90 UMA_ALIGN_PTR, 0);
91 getnewvnode("crossmp", NULL, &dead_vnodeops, &vp_crossmp);
92 vn_lock(vp_crossmp, LK_EXCLUSIVE);
93 VN_LOCK_ASHARE(vp_crossmp);
94 VOP_UNLOCK(vp_crossmp, 0);
95 }
96 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_SECOND, nameiinit, NULL);
97
98 static int lookup_shared = 1;
99 SYSCTL_INT(_vfs, OID_AUTO, lookup_shared, CTLFLAG_RWTUN, &lookup_shared, 0,
100 "Enables/Disables shared locks for path name translation");
101
102 static void
103 namei_cleanup_cnp(struct componentname *cnp)
104 {
105 uma_zfree(namei_zone, cnp->cn_pnbuf);
106 #ifdef DIAGNOSTIC
107 cnp->cn_pnbuf = NULL;
108 cnp->cn_nameptr = NULL;
109 #endif
110 }
111
112 static int
113 namei_handle_root(struct nameidata *ndp, struct vnode **dpp)
114 {
115 struct componentname *cnp;
116
117 cnp = &ndp->ni_cnd;
118 if (ndp->ni_strictrelative != 0) {
119 #ifdef KTRACE
120 if (KTRPOINT(curthread, KTR_CAPFAIL))
121 ktrcapfail(CAPFAIL_LOOKUP, NULL, NULL);
122 #endif
123 return (ENOTCAPABLE);
124 }
125 while (*(cnp->cn_nameptr) == '/') {
126 cnp->cn_nameptr++;
127 ndp->ni_pathlen--;
128 }
129 *dpp = ndp->ni_rootdir;
130 VREF(*dpp);
131 return (0);
132 }
133
134 /*
135 * Convert a pathname into a pointer to a locked vnode.
136 *
137 * The FOLLOW flag is set when symbolic links are to be followed
138 * when they occur at the end of the name translation process.
139 * Symbolic links are always followed for all other pathname
140 * components other than the last.
141 *
142 * The segflg defines whether the name is to be copied from user
143 * space or kernel space.
144 *
145 * Overall outline of namei:
146 *
147 * copy in name
148 * get starting directory
149 * while (!done && !error) {
150 * call lookup to search path.
151 * if symbolic link, massage name in buffer and continue
152 * }
153 */
154 int
155 namei(struct nameidata *ndp)
156 {
157 struct filedesc *fdp; /* pointer to file descriptor state */
158 char *cp; /* pointer into pathname argument */
159 struct vnode *dp; /* the directory we are searching */
160 struct iovec aiov; /* uio for reading symbolic links */
161 struct uio auio;
162 int error, linklen, startdir_used;
163 struct componentname *cnp = &ndp->ni_cnd;
164 struct thread *td = cnp->cn_thread;
165 struct proc *p = td->td_proc;
166
167 ndp->ni_cnd.cn_cred = ndp->ni_cnd.cn_thread->td_ucred;
168 KASSERT(cnp->cn_cred && p, ("namei: bad cred/proc"));
169 KASSERT((cnp->cn_nameiop & (~OPMASK)) == 0,
170 ("namei: nameiop contaminated with flags"));
171 KASSERT((cnp->cn_flags & OPMASK) == 0,
172 ("namei: flags contaminated with nameiops"));
173 MPASS(ndp->ni_startdir == NULL || ndp->ni_startdir->v_type == VDIR ||
174 ndp->ni_startdir->v_type == VBAD);
175 if (!lookup_shared)
176 cnp->cn_flags &= ~LOCKSHARED;
177 fdp = p->p_fd;
178
179 /* We will set this ourselves if we need it. */
180 cnp->cn_flags &= ~TRAILINGSLASH;
181
182 /*
183 * Get a buffer for the name to be translated, and copy the
184 * name into the buffer.
185 */
186 if ((cnp->cn_flags & HASBUF) == 0)
187 cnp->cn_pnbuf = uma_zalloc(namei_zone, M_WAITOK);
188 if (ndp->ni_segflg == UIO_SYSSPACE)
189 error = copystr(ndp->ni_dirp, cnp->cn_pnbuf,
190 MAXPATHLEN, (size_t *)&ndp->ni_pathlen);
191 else
192 error = copyinstr(ndp->ni_dirp, cnp->cn_pnbuf,
193 MAXPATHLEN, (size_t *)&ndp->ni_pathlen);
194
195 /*
196 * Don't allow empty pathnames.
197 */
198 if (error == 0 && *cnp->cn_pnbuf == '\0')
199 error = ENOENT;
200
201 #ifdef CAPABILITY_MODE
202 /*
203 * In capability mode, lookups must be "strictly relative" (i.e.
204 * not an absolute path, and not containing '..' components) to
205 * a real file descriptor, not the pseudo-descriptor AT_FDCWD.
206 */
207 if (error == 0 && IN_CAPABILITY_MODE(td) &&
208 (cnp->cn_flags & NOCAPCHECK) == 0) {
209 ndp->ni_strictrelative = 1;
210 if (ndp->ni_dirfd == AT_FDCWD) {
211 #ifdef KTRACE
212 if (KTRPOINT(td, KTR_CAPFAIL))
213 ktrcapfail(CAPFAIL_LOOKUP, NULL, NULL);
214 #endif
215 error = ECAPMODE;
216 }
217 }
218 #endif
219 if (error != 0) {
220 namei_cleanup_cnp(cnp);
221 ndp->ni_vp = NULL;
222 return (error);
223 }
224 ndp->ni_loopcnt = 0;
225 #ifdef KTRACE
226 if (KTRPOINT(td, KTR_NAMEI)) {
227 KASSERT(cnp->cn_thread == curthread,
228 ("namei not using curthread"));
229 ktrnamei(cnp->cn_pnbuf);
230 }
231 #endif
232 /*
233 * Get starting point for the translation.
234 */
235 FILEDESC_SLOCK(fdp);
236 ndp->ni_rootdir = fdp->fd_rdir;
237 VREF(ndp->ni_rootdir);
238 ndp->ni_topdir = fdp->fd_jdir;
239
240 /*
241 * If we are auditing the kernel pathname, save the user pathname.
242 */
243 if (cnp->cn_flags & AUDITVNODE1)
244 AUDIT_ARG_UPATH1(td, ndp->ni_dirfd, cnp->cn_pnbuf);
245 if (cnp->cn_flags & AUDITVNODE2)
246 AUDIT_ARG_UPATH2(td, ndp->ni_dirfd, cnp->cn_pnbuf);
247
248 startdir_used = 0;
249 dp = NULL;
250 cnp->cn_nameptr = cnp->cn_pnbuf;
251 if (cnp->cn_pnbuf[0] == '/') {
252 error = namei_handle_root(ndp, &dp);
253 } else {
254 if (ndp->ni_startdir != NULL) {
255 dp = ndp->ni_startdir;
256 startdir_used = 1;
257 } else if (ndp->ni_dirfd == AT_FDCWD) {
258 dp = fdp->fd_cdir;
259 VREF(dp);
260 } else {
261 cap_rights_t rights;
262
263 rights = ndp->ni_rightsneeded;
264 cap_rights_set(&rights, CAP_LOOKUP);
265
266 if (cnp->cn_flags & AUDITVNODE1)
267 AUDIT_ARG_ATFD1(ndp->ni_dirfd);
268 if (cnp->cn_flags & AUDITVNODE2)
269 AUDIT_ARG_ATFD2(ndp->ni_dirfd);
270 error = fgetvp_rights(td, ndp->ni_dirfd,
271 &rights, &ndp->ni_filecaps, &dp);
272 if (error == EINVAL)
273 error = ENOTDIR;
274 #ifdef CAPABILITIES
275 /*
276 * If file descriptor doesn't have all rights,
277 * all lookups relative to it must also be
278 * strictly relative.
279 */
280 CAP_ALL(&rights);
281 if (!cap_rights_contains(&ndp->ni_filecaps.fc_rights,
282 &rights) ||
283 ndp->ni_filecaps.fc_fcntls != CAP_FCNTL_ALL ||
284 ndp->ni_filecaps.fc_nioctls != -1) {
285 ndp->ni_strictrelative = 1;
286 }
287 #endif
288 }
289 if (error == 0 && dp->v_type != VDIR)
290 error = ENOTDIR;
291 }
292 FILEDESC_SUNLOCK(fdp);
293 if (ndp->ni_startdir != NULL && !startdir_used)
294 vrele(ndp->ni_startdir);
295 if (error != 0) {
296 if (dp != NULL)
297 vrele(dp);
298 vrele(ndp->ni_rootdir);
299 namei_cleanup_cnp(cnp);
300 return (error);
301 }
302 SDT_PROBE3(vfs, namei, lookup, entry, dp, cnp->cn_pnbuf,
303 cnp->cn_flags);
304 for (;;) {
305 ndp->ni_startdir = dp;
306 error = lookup(ndp);
307 if (error != 0) {
308 vrele(ndp->ni_rootdir);
309 namei_cleanup_cnp(cnp);
310 SDT_PROBE2(vfs, namei, lookup, return, error, NULL);
311 return (error);
312 }
313 /*
314 * If not a symbolic link, we're done.
315 */
316 if ((cnp->cn_flags & ISSYMLINK) == 0) {
317 vrele(ndp->ni_rootdir);
318 if ((cnp->cn_flags & (SAVENAME | SAVESTART)) == 0) {
319 namei_cleanup_cnp(cnp);
320 } else
321 cnp->cn_flags |= HASBUF;
322
323 SDT_PROBE2(vfs, namei, lookup, return, 0, ndp->ni_vp);
324 return (0);
325 }
326 if (ndp->ni_loopcnt++ >= MAXSYMLINKS) {
327 error = ELOOP;
328 break;
329 }
330 #ifdef MAC
331 if ((cnp->cn_flags & NOMACCHECK) == 0) {
332 error = mac_vnode_check_readlink(td->td_ucred,
333 ndp->ni_vp);
334 if (error != 0)
335 break;
336 }
337 #endif
338 if (ndp->ni_pathlen > 1)
339 cp = uma_zalloc(namei_zone, M_WAITOK);
340 else
341 cp = cnp->cn_pnbuf;
342 aiov.iov_base = cp;
343 aiov.iov_len = MAXPATHLEN;
344 auio.uio_iov = &aiov;
345 auio.uio_iovcnt = 1;
346 auio.uio_offset = 0;
347 auio.uio_rw = UIO_READ;
348 auio.uio_segflg = UIO_SYSSPACE;
349 auio.uio_td = td;
350 auio.uio_resid = MAXPATHLEN;
351 error = VOP_READLINK(ndp->ni_vp, &auio, cnp->cn_cred);
352 if (error != 0) {
353 if (ndp->ni_pathlen > 1)
354 uma_zfree(namei_zone, cp);
355 break;
356 }
357 linklen = MAXPATHLEN - auio.uio_resid;
358 if (linklen == 0) {
359 if (ndp->ni_pathlen > 1)
360 uma_zfree(namei_zone, cp);
361 error = ENOENT;
362 break;
363 }
364 if (linklen + ndp->ni_pathlen >= MAXPATHLEN) {
365 if (ndp->ni_pathlen > 1)
366 uma_zfree(namei_zone, cp);
367 error = ENAMETOOLONG;
368 break;
369 }
370 if (ndp->ni_pathlen > 1) {
371 bcopy(ndp->ni_next, cp + linklen, ndp->ni_pathlen);
372 uma_zfree(namei_zone, cnp->cn_pnbuf);
373 cnp->cn_pnbuf = cp;
374 } else
375 cnp->cn_pnbuf[linklen] = '\0';
376 ndp->ni_pathlen += linklen;
377 vput(ndp->ni_vp);
378 dp = ndp->ni_dvp;
379 /*
380 * Check if root directory should replace current directory.
381 */
382 cnp->cn_nameptr = cnp->cn_pnbuf;
383 if (*(cnp->cn_nameptr) == '/') {
384 vrele(dp);
385 error = namei_handle_root(ndp, &dp);
386 if (error != 0) {
387 vrele(ndp->ni_rootdir);
388 namei_cleanup_cnp(cnp);
389 return (error);
390 }
391 }
392 }
393 vrele(ndp->ni_rootdir);
394 namei_cleanup_cnp(cnp);
395 vput(ndp->ni_vp);
396 ndp->ni_vp = NULL;
397 vrele(ndp->ni_dvp);
398 SDT_PROBE2(vfs, namei, lookup, return, error, NULL);
399 return (error);
400 }
401
402 static int
403 compute_cn_lkflags(struct mount *mp, int lkflags, int cnflags)
404 {
405
406 if (mp == NULL || ((lkflags & LK_SHARED) &&
407 (!(mp->mnt_kern_flag & MNTK_LOOKUP_SHARED) ||
408 ((cnflags & ISDOTDOT) &&
409 (mp->mnt_kern_flag & MNTK_LOOKUP_EXCL_DOTDOT))))) {
410 lkflags &= ~LK_SHARED;
411 lkflags |= LK_EXCLUSIVE;
412 }
413 lkflags |= LK_NODDLKTREAT;
414 return (lkflags);
415 }
416
417 static __inline int
418 needs_exclusive_leaf(struct mount *mp, int flags)
419 {
420
421 /*
422 * Intermediate nodes can use shared locks, we only need to
423 * force an exclusive lock for leaf nodes.
424 */
425 if ((flags & (ISLASTCN | LOCKLEAF)) != (ISLASTCN | LOCKLEAF))
426 return (0);
427
428 /* Always use exclusive locks if LOCKSHARED isn't set. */
429 if (!(flags & LOCKSHARED))
430 return (1);
431
432 /*
433 * For lookups during open(), if the mount point supports
434 * extended shared operations, then use a shared lock for the
435 * leaf node, otherwise use an exclusive lock.
436 */
437 if ((flags & ISOPEN) != 0)
438 return (!MNT_EXTENDED_SHARED(mp));
439
440 /*
441 * Lookup requests outside of open() that specify LOCKSHARED
442 * only need a shared lock on the leaf vnode.
443 */
444 return (0);
445 }
446
447 /*
448 * Search a pathname.
449 * This is a very central and rather complicated routine.
450 *
451 * The pathname is pointed to by ni_ptr and is of length ni_pathlen.
452 * The starting directory is taken from ni_startdir. The pathname is
453 * descended until done, or a symbolic link is encountered. The variable
454 * ni_more is clear if the path is completed; it is set to one if a
455 * symbolic link needing interpretation is encountered.
456 *
457 * The flag argument is LOOKUP, CREATE, RENAME, or DELETE depending on
458 * whether the name is to be looked up, created, renamed, or deleted.
459 * When CREATE, RENAME, or DELETE is specified, information usable in
460 * creating, renaming, or deleting a directory entry may be calculated.
461 * If flag has LOCKPARENT or'ed into it, the parent directory is returned
462 * locked. If flag has WANTPARENT or'ed into it, the parent directory is
463 * returned unlocked. Otherwise the parent directory is not returned. If
464 * the target of the pathname exists and LOCKLEAF is or'ed into the flag
465 * the target is returned locked, otherwise it is returned unlocked.
466 * When creating or renaming and LOCKPARENT is specified, the target may not
467 * be ".". When deleting and LOCKPARENT is specified, the target may be ".".
468 *
469 * Overall outline of lookup:
470 *
471 * dirloop:
472 * identify next component of name at ndp->ni_ptr
473 * handle degenerate case where name is null string
474 * if .. and crossing mount points and on mounted filesys, find parent
475 * call VOP_LOOKUP routine for next component name
476 * directory vnode returned in ni_dvp, unlocked unless LOCKPARENT set
477 * component vnode returned in ni_vp (if it exists), locked.
478 * if result vnode is mounted on and crossing mount points,
479 * find mounted on vnode
480 * if more components of name, do next level at dirloop
481 * return the answer in ni_vp, locked if LOCKLEAF set
482 * if LOCKPARENT set, return locked parent in ni_dvp
483 * if WANTPARENT set, return unlocked parent in ni_dvp
484 */
485 int
486 lookup(struct nameidata *ndp)
487 {
488 char *cp; /* pointer into pathname argument */
489 struct vnode *dp = NULL; /* the directory we are searching */
490 struct vnode *tdp; /* saved dp */
491 struct mount *mp; /* mount table entry */
492 struct prison *pr;
493 int docache; /* == 0 do not cache last component */
494 int wantparent; /* 1 => wantparent or lockparent flag */
495 int rdonly; /* lookup read-only flag bit */
496 int error = 0;
497 int dpunlocked = 0; /* dp has already been unlocked */
498 int relookup = 0; /* do not consume the path component */
499 struct componentname *cnp = &ndp->ni_cnd;
500 int lkflags_save;
501 int ni_dvp_unlocked;
502
503 /*
504 * Setup: break out flag bits into variables.
505 */
506 ni_dvp_unlocked = 0;
507 wantparent = cnp->cn_flags & (LOCKPARENT | WANTPARENT);
508 KASSERT(cnp->cn_nameiop == LOOKUP || wantparent,
509 ("CREATE, DELETE, RENAME require LOCKPARENT or WANTPARENT."));
510 docache = (cnp->cn_flags & NOCACHE) ^ NOCACHE;
511 if (cnp->cn_nameiop == DELETE ||
512 (wantparent && cnp->cn_nameiop != CREATE &&
513 cnp->cn_nameiop != LOOKUP))
514 docache = 0;
515 rdonly = cnp->cn_flags & RDONLY;
516 cnp->cn_flags &= ~ISSYMLINK;
517 ndp->ni_dvp = NULL;
518 /*
519 * We use shared locks until we hit the parent of the last cn then
520 * we adjust based on the requesting flags.
521 */
522 if (lookup_shared)
523 cnp->cn_lkflags = LK_SHARED;
524 else
525 cnp->cn_lkflags = LK_EXCLUSIVE;
526 dp = ndp->ni_startdir;
527 ndp->ni_startdir = NULLVP;
528 vn_lock(dp,
529 compute_cn_lkflags(dp->v_mount, cnp->cn_lkflags | LK_RETRY,
530 cnp->cn_flags));
531
532 dirloop:
533 /*
534 * Search a new directory.
535 *
536 * The last component of the filename is left accessible via
537 * cnp->cn_nameptr for callers that need the name. Callers needing
538 * the name set the SAVENAME flag. When done, they assume
539 * responsibility for freeing the pathname buffer.
540 */
541 for (cp = cnp->cn_nameptr; *cp != 0 && *cp != '/'; cp++)
542 continue;
543 cnp->cn_namelen = cp - cnp->cn_nameptr;
544 if (cnp->cn_namelen > NAME_MAX) {
545 error = ENAMETOOLONG;
546 goto bad;
547 }
548 #ifdef NAMEI_DIAGNOSTIC
549 { char c = *cp;
550 *cp = '\0';
551 printf("{%s}: ", cnp->cn_nameptr);
552 *cp = c; }
553 #endif
554 ndp->ni_pathlen -= cnp->cn_namelen;
555 ndp->ni_next = cp;
556
557 /*
558 * Replace multiple slashes by a single slash and trailing slashes
559 * by a null. This must be done before VOP_LOOKUP() because some
560 * fs's don't know about trailing slashes. Remember if there were
561 * trailing slashes to handle symlinks, existing non-directories
562 * and non-existing files that won't be directories specially later.
563 */
564 while (*cp == '/' && (cp[1] == '/' || cp[1] == '\0')) {
565 cp++;
566 ndp->ni_pathlen--;
567 if (*cp == '\0') {
568 *ndp->ni_next = '\0';
569 cnp->cn_flags |= TRAILINGSLASH;
570 }
571 }
572 ndp->ni_next = cp;
573
574 cnp->cn_flags |= MAKEENTRY;
575 if (*cp == '\0' && docache == 0)
576 cnp->cn_flags &= ~MAKEENTRY;
577 if (cnp->cn_namelen == 2 &&
578 cnp->cn_nameptr[1] == '.' && cnp->cn_nameptr[0] == '.')
579 cnp->cn_flags |= ISDOTDOT;
580 else
581 cnp->cn_flags &= ~ISDOTDOT;
582 if (*ndp->ni_next == 0)
583 cnp->cn_flags |= ISLASTCN;
584 else
585 cnp->cn_flags &= ~ISLASTCN;
586
587 if ((cnp->cn_flags & ISLASTCN) != 0 &&
588 cnp->cn_namelen == 1 && cnp->cn_nameptr[0] == '.' &&
589 (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME)) {
590 error = EINVAL;
591 goto bad;
592 }
593
594 /*
595 * Check for degenerate name (e.g. / or "")
596 * which is a way of talking about a directory,
597 * e.g. like "/." or ".".
598 */
599 if (cnp->cn_nameptr[0] == '\0') {
600 if (dp->v_type != VDIR) {
601 error = ENOTDIR;
602 goto bad;
603 }
604 if (cnp->cn_nameiop != LOOKUP) {
605 error = EISDIR;
606 goto bad;
607 }
608 if (wantparent) {
609 ndp->ni_dvp = dp;
610 VREF(dp);
611 }
612 ndp->ni_vp = dp;
613
614 if (cnp->cn_flags & AUDITVNODE1)
615 AUDIT_ARG_VNODE1(dp);
616 else if (cnp->cn_flags & AUDITVNODE2)
617 AUDIT_ARG_VNODE2(dp);
618
619 if (!(cnp->cn_flags & (LOCKPARENT | LOCKLEAF)))
620 VOP_UNLOCK(dp, 0);
621 /* XXX This should probably move to the top of function. */
622 if (cnp->cn_flags & SAVESTART)
623 panic("lookup: SAVESTART");
624 goto success;
625 }
626
627 /*
628 * Handle "..": five special cases.
629 * 0. If doing a capability lookup, return ENOTCAPABLE (this is a
630 * fairly conservative design choice, but it's the only one that we
631 * are satisfied guarantees the property we're looking for).
632 * 1. Return an error if this is the last component of
633 * the name and the operation is DELETE or RENAME.
634 * 2. If at root directory (e.g. after chroot)
635 * or at absolute root directory
636 * then ignore it so can't get out.
637 * 3. If this vnode is the root of a mounted
638 * filesystem, then replace it with the
639 * vnode which was mounted on so we take the
640 * .. in the other filesystem.
641 * 4. If the vnode is the top directory of
642 * the jail or chroot, don't let them out.
643 */
644 if (cnp->cn_flags & ISDOTDOT) {
645 if (ndp->ni_strictrelative != 0) {
646 #ifdef KTRACE
647 if (KTRPOINT(curthread, KTR_CAPFAIL))
648 ktrcapfail(CAPFAIL_LOOKUP, NULL, NULL);
649 #endif
650 error = ENOTCAPABLE;
651 goto bad;
652 }
653 if ((cnp->cn_flags & ISLASTCN) != 0 &&
654 (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME)) {
655 error = EINVAL;
656 goto bad;
657 }
658 for (;;) {
659 for (pr = cnp->cn_cred->cr_prison; pr != NULL;
660 pr = pr->pr_parent)
661 if (dp == pr->pr_root)
662 break;
663 if (dp == ndp->ni_rootdir ||
664 dp == ndp->ni_topdir ||
665 dp == rootvnode ||
666 pr != NULL ||
667 ((dp->v_vflag & VV_ROOT) != 0 &&
668 (cnp->cn_flags & NOCROSSMOUNT) != 0)) {
669 ndp->ni_dvp = dp;
670 ndp->ni_vp = dp;
671 VREF(dp);
672 goto nextname;
673 }
674 if ((dp->v_vflag & VV_ROOT) == 0)
675 break;
676 if (dp->v_iflag & VI_DOOMED) { /* forced unmount */
677 error = ENOENT;
678 goto bad;
679 }
680 tdp = dp;
681 dp = dp->v_mount->mnt_vnodecovered;
682 VREF(dp);
683 vput(tdp);
684 vn_lock(dp,
685 compute_cn_lkflags(dp->v_mount, cnp->cn_lkflags |
686 LK_RETRY, ISDOTDOT));
687 }
688 }
689
690 /*
691 * We now have a segment name to search for, and a directory to search.
692 */
693 unionlookup:
694 #ifdef MAC
695 if ((cnp->cn_flags & NOMACCHECK) == 0) {
696 error = mac_vnode_check_lookup(cnp->cn_thread->td_ucred, dp,
697 cnp);
698 if (error)
699 goto bad;
700 }
701 #endif
702 ndp->ni_dvp = dp;
703 ndp->ni_vp = NULL;
704 ASSERT_VOP_LOCKED(dp, "lookup");
705 /*
706 * If we have a shared lock we may need to upgrade the lock for the
707 * last operation.
708 */
709 if (dp != vp_crossmp &&
710 VOP_ISLOCKED(dp) == LK_SHARED &&
711 (cnp->cn_flags & ISLASTCN) && (cnp->cn_flags & LOCKPARENT))
712 vn_lock(dp, LK_UPGRADE|LK_RETRY);
713 if ((dp->v_iflag & VI_DOOMED) != 0) {
714 error = ENOENT;
715 goto bad;
716 }
717 /*
718 * If we're looking up the last component and we need an exclusive
719 * lock, adjust our lkflags.
720 */
721 if (needs_exclusive_leaf(dp->v_mount, cnp->cn_flags))
722 cnp->cn_lkflags = LK_EXCLUSIVE;
723 #ifdef NAMEI_DIAGNOSTIC
724 vprint("lookup in", dp);
725 #endif
726 lkflags_save = cnp->cn_lkflags;
727 cnp->cn_lkflags = compute_cn_lkflags(dp->v_mount, cnp->cn_lkflags,
728 cnp->cn_flags);
729 error = VOP_LOOKUP(dp, &ndp->ni_vp, cnp);
730 cnp->cn_lkflags = lkflags_save;
731 if (error != 0) {
732 KASSERT(ndp->ni_vp == NULL, ("leaf should be empty"));
733 #ifdef NAMEI_DIAGNOSTIC
734 printf("not found\n");
735 #endif
736 if ((error == ENOENT) &&
737 (dp->v_vflag & VV_ROOT) && (dp->v_mount != NULL) &&
738 (dp->v_mount->mnt_flag & MNT_UNION)) {
739 tdp = dp;
740 dp = dp->v_mount->mnt_vnodecovered;
741 VREF(dp);
742 vput(tdp);
743 vn_lock(dp,
744 compute_cn_lkflags(dp->v_mount, cnp->cn_lkflags |
745 LK_RETRY, cnp->cn_flags));
746 goto unionlookup;
747 }
748
749 if (error == ERELOOKUP) {
750 vref(dp);
751 ndp->ni_vp = dp;
752 error = 0;
753 relookup = 1;
754 goto good;
755 }
756
757 if (error != EJUSTRETURN)
758 goto bad;
759 /*
760 * At this point, we know we're at the end of the
761 * pathname. If creating / renaming, we can consider
762 * allowing the file or directory to be created / renamed,
763 * provided we're not on a read-only filesystem.
764 */
765 if (rdonly) {
766 error = EROFS;
767 goto bad;
768 }
769 /* trailing slash only allowed for directories */
770 if ((cnp->cn_flags & TRAILINGSLASH) &&
771 !(cnp->cn_flags & WILLBEDIR)) {
772 error = ENOENT;
773 goto bad;
774 }
775 if ((cnp->cn_flags & LOCKPARENT) == 0)
776 VOP_UNLOCK(dp, 0);
777 /*
778 * We return with ni_vp NULL to indicate that the entry
779 * doesn't currently exist, leaving a pointer to the
780 * (possibly locked) directory vnode in ndp->ni_dvp.
781 */
782 if (cnp->cn_flags & SAVESTART) {
783 ndp->ni_startdir = ndp->ni_dvp;
784 VREF(ndp->ni_startdir);
785 }
786 goto success;
787 }
788
789 good:
790 #ifdef NAMEI_DIAGNOSTIC
791 printf("found\n");
792 #endif
793 dp = ndp->ni_vp;
794
795 /*
796 * Check to see if the vnode has been mounted on;
797 * if so find the root of the mounted filesystem.
798 */
799 while (dp->v_type == VDIR && (mp = dp->v_mountedhere) &&
800 (cnp->cn_flags & NOCROSSMOUNT) == 0) {
801 if (vfs_busy(mp, 0))
802 continue;
803 vput(dp);
804 if (dp != ndp->ni_dvp)
805 vput(ndp->ni_dvp);
806 else
807 vrele(ndp->ni_dvp);
808 vref(vp_crossmp);
809 ndp->ni_dvp = vp_crossmp;
810 error = VFS_ROOT(mp, compute_cn_lkflags(mp, cnp->cn_lkflags,
811 cnp->cn_flags), &tdp);
812 vfs_unbusy(mp);
813 if (vn_lock(vp_crossmp, LK_SHARED | LK_NOWAIT))
814 panic("vp_crossmp exclusively locked or reclaimed");
815 if (error) {
816 dpunlocked = 1;
817 goto bad2;
818 }
819 ndp->ni_vp = dp = tdp;
820 }
821
822 /*
823 * Check for symbolic link
824 */
825 if ((dp->v_type == VLNK) &&
826 ((cnp->cn_flags & FOLLOW) || (cnp->cn_flags & TRAILINGSLASH) ||
827 *ndp->ni_next == '/')) {
828 cnp->cn_flags |= ISSYMLINK;
829 if (dp->v_iflag & VI_DOOMED) {
830 /*
831 * We can't know whether the directory was mounted with
832 * NOSYMFOLLOW, so we can't follow safely.
833 */
834 error = ENOENT;
835 goto bad2;
836 }
837 if (dp->v_mount->mnt_flag & MNT_NOSYMFOLLOW) {
838 error = EACCES;
839 goto bad2;
840 }
841 /*
842 * Symlink code always expects an unlocked dvp.
843 */
844 if (ndp->ni_dvp != ndp->ni_vp) {
845 VOP_UNLOCK(ndp->ni_dvp, 0);
846 ni_dvp_unlocked = 1;
847 }
848 goto success;
849 }
850
851 nextname:
852 /*
853 * Not a symbolic link that we will follow. Continue with the
854 * next component if there is any; otherwise, we're done.
855 */
856 KASSERT((cnp->cn_flags & ISLASTCN) || *ndp->ni_next == '/',
857 ("lookup: invalid path state."));
858 if (relookup) {
859 relookup = 0;
860 if (ndp->ni_dvp != dp)
861 vput(ndp->ni_dvp);
862 else
863 vrele(ndp->ni_dvp);
864 goto dirloop;
865 }
866 if (*ndp->ni_next == '/') {
867 cnp->cn_nameptr = ndp->ni_next;
868 while (*cnp->cn_nameptr == '/') {
869 cnp->cn_nameptr++;
870 ndp->ni_pathlen--;
871 }
872 if (ndp->ni_dvp != dp)
873 vput(ndp->ni_dvp);
874 else
875 vrele(ndp->ni_dvp);
876 goto dirloop;
877 }
878 /*
879 * If we're processing a path with a trailing slash,
880 * check that the end result is a directory.
881 */
882 if ((cnp->cn_flags & TRAILINGSLASH) && dp->v_type != VDIR) {
883 error = ENOTDIR;
884 goto bad2;
885 }
886 /*
887 * Disallow directory write attempts on read-only filesystems.
888 */
889 if (rdonly &&
890 (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME)) {
891 error = EROFS;
892 goto bad2;
893 }
894 if (cnp->cn_flags & SAVESTART) {
895 ndp->ni_startdir = ndp->ni_dvp;
896 VREF(ndp->ni_startdir);
897 }
898 if (!wantparent) {
899 ni_dvp_unlocked = 2;
900 if (ndp->ni_dvp != dp)
901 vput(ndp->ni_dvp);
902 else
903 vrele(ndp->ni_dvp);
904 } else if ((cnp->cn_flags & LOCKPARENT) == 0 && ndp->ni_dvp != dp) {
905 VOP_UNLOCK(ndp->ni_dvp, 0);
906 ni_dvp_unlocked = 1;
907 }
908
909 if (cnp->cn_flags & AUDITVNODE1)
910 AUDIT_ARG_VNODE1(dp);
911 else if (cnp->cn_flags & AUDITVNODE2)
912 AUDIT_ARG_VNODE2(dp);
913
914 if ((cnp->cn_flags & LOCKLEAF) == 0)
915 VOP_UNLOCK(dp, 0);
916 success:
917 /*
918 * Because of lookup_shared we may have the vnode shared locked, but
919 * the caller may want it to be exclusively locked.
920 */
921 if (needs_exclusive_leaf(dp->v_mount, cnp->cn_flags) &&
922 VOP_ISLOCKED(dp) != LK_EXCLUSIVE) {
923 vn_lock(dp, LK_UPGRADE | LK_RETRY);
924 if (dp->v_iflag & VI_DOOMED) {
925 error = ENOENT;
926 goto bad2;
927 }
928 }
929 return (0);
930
931 bad2:
932 if (ni_dvp_unlocked != 2) {
933 if (dp != ndp->ni_dvp && !ni_dvp_unlocked)
934 vput(ndp->ni_dvp);
935 else
936 vrele(ndp->ni_dvp);
937 }
938 bad:
939 if (!dpunlocked)
940 vput(dp);
941 ndp->ni_vp = NULL;
942 return (error);
943 }
944
945 /*
946 * relookup - lookup a path name component
947 * Used by lookup to re-acquire things.
948 */
949 int
950 relookup(struct vnode *dvp, struct vnode **vpp, struct componentname *cnp)
951 {
952 struct vnode *dp = NULL; /* the directory we are searching */
953 int wantparent; /* 1 => wantparent or lockparent flag */
954 int rdonly; /* lookup read-only flag bit */
955 int error = 0;
956
957 KASSERT(cnp->cn_flags & ISLASTCN,
958 ("relookup: Not given last component."));
959 /*
960 * Setup: break out flag bits into variables.
961 */
962 wantparent = cnp->cn_flags & (LOCKPARENT|WANTPARENT);
963 KASSERT(wantparent, ("relookup: parent not wanted."));
964 rdonly = cnp->cn_flags & RDONLY;
965 cnp->cn_flags &= ~ISSYMLINK;
966 dp = dvp;
967 cnp->cn_lkflags = LK_EXCLUSIVE;
968 vn_lock(dp, LK_EXCLUSIVE | LK_RETRY);
969
970 /*
971 * Search a new directory.
972 *
973 * The last component of the filename is left accessible via
974 * cnp->cn_nameptr for callers that need the name. Callers needing
975 * the name set the SAVENAME flag. When done, they assume
976 * responsibility for freeing the pathname buffer.
977 */
978 #ifdef NAMEI_DIAGNOSTIC
979 printf("{%s}: ", cnp->cn_nameptr);
980 #endif
981
982 /*
983 * Check for "" which represents the root directory after slash
984 * removal.
985 */
986 if (cnp->cn_nameptr[0] == '\0') {
987 /*
988 * Support only LOOKUP for "/" because lookup()
989 * can't succeed for CREATE, DELETE and RENAME.
990 */
991 KASSERT(cnp->cn_nameiop == LOOKUP, ("nameiop must be LOOKUP"));
992 KASSERT(dp->v_type == VDIR, ("dp is not a directory"));
993
994 if (!(cnp->cn_flags & LOCKLEAF))
995 VOP_UNLOCK(dp, 0);
996 *vpp = dp;
997 /* XXX This should probably move to the top of function. */
998 if (cnp->cn_flags & SAVESTART)
999 panic("lookup: SAVESTART");
1000 return (0);
1001 }
1002
1003 if (cnp->cn_flags & ISDOTDOT)
1004 panic ("relookup: lookup on dot-dot");
1005
1006 /*
1007 * We now have a segment name to search for, and a directory to search.
1008 */
1009 #ifdef NAMEI_DIAGNOSTIC
1010 vprint("search in:", dp);
1011 #endif
1012 if ((error = VOP_LOOKUP(dp, vpp, cnp)) != 0) {
1013 KASSERT(*vpp == NULL, ("leaf should be empty"));
1014 if (error != EJUSTRETURN)
1015 goto bad;
1016 /*
1017 * If creating and at end of pathname, then can consider
1018 * allowing file to be created.
1019 */
1020 if (rdonly) {
1021 error = EROFS;
1022 goto bad;
1023 }
1024 /* ASSERT(dvp == ndp->ni_startdir) */
1025 if (cnp->cn_flags & SAVESTART)
1026 VREF(dvp);
1027 if ((cnp->cn_flags & LOCKPARENT) == 0)
1028 VOP_UNLOCK(dp, 0);
1029 /*
1030 * We return with ni_vp NULL to indicate that the entry
1031 * doesn't currently exist, leaving a pointer to the
1032 * (possibly locked) directory vnode in ndp->ni_dvp.
1033 */
1034 return (0);
1035 }
1036
1037 dp = *vpp;
1038
1039 /*
1040 * Disallow directory write attempts on read-only filesystems.
1041 */
1042 if (rdonly &&
1043 (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME)) {
1044 if (dvp == dp)
1045 vrele(dvp);
1046 else
1047 vput(dvp);
1048 error = EROFS;
1049 goto bad;
1050 }
1051 /*
1052 * Set the parent lock/ref state to the requested state.
1053 */
1054 if ((cnp->cn_flags & LOCKPARENT) == 0 && dvp != dp) {
1055 if (wantparent)
1056 VOP_UNLOCK(dvp, 0);
1057 else
1058 vput(dvp);
1059 } else if (!wantparent)
1060 vrele(dvp);
1061 /*
1062 * Check for symbolic link
1063 */
1064 KASSERT(dp->v_type != VLNK || !(cnp->cn_flags & FOLLOW),
1065 ("relookup: symlink found.\n"));
1066
1067 /* ASSERT(dvp == ndp->ni_startdir) */
1068 if (cnp->cn_flags & SAVESTART)
1069 VREF(dvp);
1070
1071 if ((cnp->cn_flags & LOCKLEAF) == 0)
1072 VOP_UNLOCK(dp, 0);
1073 return (0);
1074 bad:
1075 vput(dp);
1076 *vpp = NULL;
1077 return (error);
1078 }
1079
1080 void
1081 NDINIT_ALL(struct nameidata *ndp, u_long op, u_long flags, enum uio_seg segflg,
1082 const char *namep, int dirfd, struct vnode *startdir, cap_rights_t *rightsp,
1083 struct thread *td)
1084 {
1085
1086 ndp->ni_cnd.cn_nameiop = op;
1087 ndp->ni_cnd.cn_flags = flags;
1088 ndp->ni_segflg = segflg;
1089 ndp->ni_dirp = namep;
1090 ndp->ni_dirfd = dirfd;
1091 ndp->ni_startdir = startdir;
1092 ndp->ni_strictrelative = 0;
1093 if (rightsp != NULL)
1094 ndp->ni_rightsneeded = *rightsp;
1095 else
1096 cap_rights_init(&ndp->ni_rightsneeded);
1097 filecaps_init(&ndp->ni_filecaps);
1098 ndp->ni_cnd.cn_thread = td;
1099 }
1100
1101 /*
1102 * Free data allocated by namei(); see namei(9) for details.
1103 */
1104 void
1105 NDFREE(struct nameidata *ndp, const u_int flags)
1106 {
1107 int unlock_dvp;
1108 int unlock_vp;
1109
1110 unlock_dvp = 0;
1111 unlock_vp = 0;
1112
1113 if (!(flags & NDF_NO_FREE_PNBUF) &&
1114 (ndp->ni_cnd.cn_flags & HASBUF)) {
1115 uma_zfree(namei_zone, ndp->ni_cnd.cn_pnbuf);
1116 ndp->ni_cnd.cn_flags &= ~HASBUF;
1117 }
1118 if (!(flags & NDF_NO_VP_UNLOCK) &&
1119 (ndp->ni_cnd.cn_flags & LOCKLEAF) && ndp->ni_vp)
1120 unlock_vp = 1;
1121 if (!(flags & NDF_NO_VP_RELE) && ndp->ni_vp) {
1122 if (unlock_vp) {
1123 vput(ndp->ni_vp);
1124 unlock_vp = 0;
1125 } else
1126 vrele(ndp->ni_vp);
1127 ndp->ni_vp = NULL;
1128 }
1129 if (unlock_vp)
1130 VOP_UNLOCK(ndp->ni_vp, 0);
1131 if (!(flags & NDF_NO_DVP_UNLOCK) &&
1132 (ndp->ni_cnd.cn_flags & LOCKPARENT) &&
1133 ndp->ni_dvp != ndp->ni_vp)
1134 unlock_dvp = 1;
1135 if (!(flags & NDF_NO_DVP_RELE) &&
1136 (ndp->ni_cnd.cn_flags & (LOCKPARENT|WANTPARENT))) {
1137 if (unlock_dvp) {
1138 vput(ndp->ni_dvp);
1139 unlock_dvp = 0;
1140 } else
1141 vrele(ndp->ni_dvp);
1142 ndp->ni_dvp = NULL;
1143 }
1144 if (unlock_dvp)
1145 VOP_UNLOCK(ndp->ni_dvp, 0);
1146 if (!(flags & NDF_NO_STARTDIR_RELE) &&
1147 (ndp->ni_cnd.cn_flags & SAVESTART)) {
1148 vrele(ndp->ni_startdir);
1149 ndp->ni_startdir = NULL;
1150 }
1151 }
1152
1153 /*
1154 * Determine if there is a suitable alternate filename under the specified
1155 * prefix for the specified path. If the create flag is set, then the
1156 * alternate prefix will be used so long as the parent directory exists.
1157 * This is used by the various compatibility ABIs so that Linux binaries prefer
1158 * files under /compat/linux for example. The chosen path (whether under
1159 * the prefix or under /) is returned in a kernel malloc'd buffer pointed
1160 * to by pathbuf. The caller is responsible for free'ing the buffer from
1161 * the M_TEMP bucket if one is returned.
1162 */
1163 int
1164 kern_alternate_path(struct thread *td, const char *prefix, const char *path,
1165 enum uio_seg pathseg, char **pathbuf, int create, int dirfd)
1166 {
1167 struct nameidata nd, ndroot;
1168 char *ptr, *buf, *cp;
1169 size_t len, sz;
1170 int error;
1171
1172 buf = (char *) malloc(MAXPATHLEN, M_TEMP, M_WAITOK);
1173 *pathbuf = buf;
1174
1175 /* Copy the prefix into the new pathname as a starting point. */
1176 len = strlcpy(buf, prefix, MAXPATHLEN);
1177 if (len >= MAXPATHLEN) {
1178 *pathbuf = NULL;
1179 free(buf, M_TEMP);
1180 return (EINVAL);
1181 }
1182 sz = MAXPATHLEN - len;
1183 ptr = buf + len;
1184
1185 /* Append the filename to the prefix. */
1186 if (pathseg == UIO_SYSSPACE)
1187 error = copystr(path, ptr, sz, &len);
1188 else
1189 error = copyinstr(path, ptr, sz, &len);
1190
1191 if (error) {
1192 *pathbuf = NULL;
1193 free(buf, M_TEMP);
1194 return (error);
1195 }
1196
1197 /* Only use a prefix with absolute pathnames. */
1198 if (*ptr != '/') {
1199 error = EINVAL;
1200 goto keeporig;
1201 }
1202
1203 if (dirfd != AT_FDCWD) {
1204 /*
1205 * We want the original because the "prefix" is
1206 * included in the already opened dirfd.
1207 */
1208 bcopy(ptr, buf, len);
1209 return (0);
1210 }
1211
1212 /*
1213 * We know that there is a / somewhere in this pathname.
1214 * Search backwards for it, to find the file's parent dir
1215 * to see if it exists in the alternate tree. If it does,
1216 * and we want to create a file (cflag is set). We don't
1217 * need to worry about the root comparison in this case.
1218 */
1219
1220 if (create) {
1221 for (cp = &ptr[len] - 1; *cp != '/'; cp--);
1222 *cp = '\0';
1223
1224 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, buf, td);
1225 error = namei(&nd);
1226 *cp = '/';
1227 if (error != 0)
1228 goto keeporig;
1229 } else {
1230 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, buf, td);
1231
1232 error = namei(&nd);
1233 if (error != 0)
1234 goto keeporig;
1235
1236 /*
1237 * We now compare the vnode of the prefix to the one
1238 * vnode asked. If they resolve to be the same, then we
1239 * ignore the match so that the real root gets used.
1240 * This avoids the problem of traversing "../.." to find the
1241 * root directory and never finding it, because "/" resolves
1242 * to the emulation root directory. This is expensive :-(
1243 */
1244 NDINIT(&ndroot, LOOKUP, FOLLOW, UIO_SYSSPACE, prefix,
1245 td);
1246
1247 /* We shouldn't ever get an error from this namei(). */
1248 error = namei(&ndroot);
1249 if (error == 0) {
1250 if (nd.ni_vp == ndroot.ni_vp)
1251 error = ENOENT;
1252
1253 NDFREE(&ndroot, NDF_ONLY_PNBUF);
1254 vrele(ndroot.ni_vp);
1255 }
1256 }
1257
1258 NDFREE(&nd, NDF_ONLY_PNBUF);
1259 vrele(nd.ni_vp);
1260
1261 keeporig:
1262 /* If there was an error, use the original path name. */
1263 if (error)
1264 bcopy(ptr, buf, len);
1265 return (error);
1266 }
Cache object: 1cb159fd1dab14de636f7b7e403ef0b6
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