1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1989, 1993
5 * The Regents of the University of California. All rights reserved.
6 * (c) UNIX System Laboratories, Inc.
7 * All or some portions of this file are derived from material licensed
8 * to the University of California by American Telephone and Telegraph
9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10 * the permission of UNIX System Laboratories, Inc.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 */
36
37 #include <sys/cdefs.h>
38 #include "opt_ufs.h"
39 #include "opt_quota.h"
40
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/kernel.h>
44 #include <sys/namei.h>
45 #include <sys/bio.h>
46 #include <sys/buf.h>
47 #include <sys/proc.h>
48 #include <sys/stat.h>
49 #include <sys/mount.h>
50 #include <sys/vnode.h>
51 #include <sys/sysctl.h>
52
53 #include <vm/vm.h>
54 #include <vm/vm_extern.h>
55
56 #include <ufs/ufs/extattr.h>
57 #include <ufs/ufs/quota.h>
58 #include <ufs/ufs/inode.h>
59 #include <ufs/ufs/dir.h>
60 #ifdef UFS_DIRHASH
61 #include <ufs/ufs/dirhash.h>
62 #endif
63 #include <ufs/ufs/ufsmount.h>
64 #include <ufs/ufs/ufs_extern.h>
65 #include <ufs/ffs/ffs_extern.h>
66
67 #ifdef DIAGNOSTIC
68 static int dirchk = 1;
69 #else
70 static int dirchk = 0;
71 #endif
72
73 SYSCTL_INT(_debug, OID_AUTO, dircheck, CTLFLAG_RW, &dirchk, 0, "");
74
75 static int
ufs_delete_denied(struct vnode * vdp,struct vnode * tdp,struct ucred * cred,struct thread * td)76 ufs_delete_denied(struct vnode *vdp, struct vnode *tdp, struct ucred *cred,
77 struct thread *td)
78 {
79 int error;
80
81 #ifdef UFS_ACL
82 /*
83 * NFSv4 Minor Version 1, draft-ietf-nfsv4-minorversion1-03.txt
84 *
85 * 3.16.2.1. ACE4_DELETE vs. ACE4_DELETE_CHILD
86 */
87
88 /*
89 * XXX: Is this check required?
90 */
91 error = VOP_ACCESS(vdp, VEXEC, cred, td);
92 if (error)
93 return (error);
94
95 error = VOP_ACCESSX(tdp, VDELETE, cred, td);
96 if (error == 0)
97 return (0);
98
99 error = VOP_ACCESSX(vdp, VDELETE_CHILD, cred, td);
100 if (error == 0)
101 return (0);
102
103 error = VOP_ACCESSX(vdp, VEXPLICIT_DENY | VDELETE_CHILD, cred, td);
104 if (error)
105 return (error);
106
107 #endif /* !UFS_ACL */
108
109 /*
110 * Standard Unix access control - delete access requires VWRITE.
111 */
112 error = VOP_ACCESS(vdp, VWRITE, cred, td);
113 if (error)
114 return (error);
115
116 /*
117 * If directory is "sticky", then user must own
118 * the directory, or the file in it, else she
119 * may not delete it (unless she's root). This
120 * implements append-only directories.
121 */
122 if ((VTOI(vdp)->i_mode & ISVTX) &&
123 VOP_ACCESS(vdp, VADMIN, cred, td) &&
124 VOP_ACCESS(tdp, VADMIN, cred, td))
125 return (EPERM);
126
127 return (0);
128 }
129
130 /*
131 * Convert a component of a pathname into a pointer to a locked inode.
132 * This is a very central and rather complicated routine.
133 * If the filesystem is not maintained in a strict tree hierarchy,
134 * this can result in a deadlock situation (see comments in code below).
135 *
136 * The cnp->cn_nameiop argument is LOOKUP, CREATE, RENAME, or DELETE depending
137 * on whether the name is to be looked up, created, renamed, or deleted.
138 * When CREATE, RENAME, or DELETE is specified, information usable in
139 * creating, renaming, or deleting a directory entry may be calculated.
140 * If flag has LOCKPARENT or'ed into it and the target of the pathname
141 * exists, lookup returns both the target and its parent directory locked.
142 * When creating or renaming and LOCKPARENT is specified, the target may
143 * not be ".". When deleting and LOCKPARENT is specified, the target may
144 * be "."., but the caller must check to ensure it does an vrele and vput
145 * instead of two vputs.
146 *
147 * This routine is actually used as VOP_CACHEDLOOKUP method, and the
148 * filesystem employs the generic vfs_cache_lookup() as VOP_LOOKUP
149 * method.
150 *
151 * vfs_cache_lookup() performs the following for us:
152 * check that it is a directory
153 * check accessibility of directory
154 * check for modification attempts on read-only mounts
155 * if name found in cache
156 * if at end of path and deleting or creating
157 * drop it
158 * else
159 * return name.
160 * return VOP_CACHEDLOOKUP()
161 *
162 * Overall outline of ufs_lookup:
163 *
164 * search for name in directory, to found or notfound
165 * notfound:
166 * if creating, return locked directory, leaving info on available slots
167 * else return error
168 * found:
169 * if at end of path and deleting, return information to allow delete
170 * if at end of path and rewriting (RENAME and LOCKPARENT), lock target
171 * inode and return info to allow rewrite
172 * if not at end, add name to cache; if at end and neither creating
173 * nor deleting, add name to cache
174 */
175 int
ufs_lookup(struct vop_cachedlookup_args * ap)176 ufs_lookup(
177 struct vop_cachedlookup_args /* {
178 struct vnode *a_dvp;
179 struct vnode **a_vpp;
180 struct componentname *a_cnp;
181 } */ *ap)
182 {
183
184 return (ufs_lookup_ino(ap->a_dvp, ap->a_vpp, ap->a_cnp, NULL));
185 }
186
187 int
ufs_lookup_ino(struct vnode * vdp,struct vnode ** vpp,struct componentname * cnp,ino_t * dd_ino)188 ufs_lookup_ino(struct vnode *vdp, struct vnode **vpp, struct componentname *cnp,
189 ino_t *dd_ino)
190 {
191 struct inode *dp; /* inode for directory being searched */
192 struct buf *bp; /* a buffer of directory entries */
193 struct direct *ep; /* the current directory entry */
194 int entryoffsetinblock; /* offset of ep in bp's buffer */
195 enum {NONE, COMPACT, FOUND} slotstatus;
196 doff_t slotoffset; /* offset of area with free space */
197 doff_t i_diroff; /* cached i_diroff value. */
198 doff_t i_offset; /* cached i_offset value. */
199 int slotsize; /* size of area at slotoffset */
200 int slotfreespace; /* amount of space free in slot */
201 int slotneeded; /* size of the entry we're seeking */
202 int numdirpasses; /* strategy for directory search */
203 doff_t endsearch; /* offset to end directory search */
204 doff_t prevoff; /* prev entry dp->i_offset */
205 struct vnode *pdp; /* saved dp during symlink work */
206 struct vnode *tdp; /* returned by VFS_VGET */
207 doff_t enduseful; /* pointer past last used dir slot */
208 uint64_t bmask; /* block offset mask */
209 int namlen, error;
210 struct ucred *cred = cnp->cn_cred;
211 int flags = cnp->cn_flags;
212 int nameiop = cnp->cn_nameiop;
213 ino_t ino, ino1;
214 int ltype;
215
216 if (vpp != NULL)
217 *vpp = NULL;
218
219 dp = VTOI(vdp);
220 if (dp->i_effnlink == 0)
221 return (ENOENT);
222
223 /*
224 * Create a vm object if vmiodirenable is enabled.
225 * Alternatively we could call vnode_create_vobject
226 * in VFS_VGET but we could end up creating objects
227 * that are never used.
228 */
229 vnode_create_vobject(vdp, DIP(dp, i_size), curthread);
230
231 bmask = VFSTOUFS(vdp->v_mount)->um_mountp->mnt_stat.f_iosize - 1;
232
233 #ifdef DEBUG_VFS_LOCKS
234 /*
235 * Assert that the directory vnode is locked, and locked
236 * exclusively for the last component lookup for modifying
237 * operations.
238 *
239 * The directory-modifying operations need to save
240 * intermediate state in the inode between namei() call and
241 * actual directory manipulations. See fields in the struct
242 * inode marked as 'used during directory lookup'. We must
243 * ensure that upgrade in namei() does not happen, since
244 * upgrade might need to unlock vdp. If quotas are enabled,
245 * getinoquota() also requires exclusive lock to modify inode.
246 */
247 ASSERT_VOP_LOCKED(vdp, "ufs_lookup1");
248 if ((nameiop == CREATE || nameiop == DELETE || nameiop == RENAME) &&
249 (flags & (LOCKPARENT | ISLASTCN)) == (LOCKPARENT | ISLASTCN))
250 ASSERT_VOP_ELOCKED(vdp, "ufs_lookup2");
251 #endif
252
253 restart:
254 bp = NULL;
255 slotoffset = -1;
256
257 /*
258 * We now have a segment name to search for, and a directory to search.
259 *
260 * Suppress search for slots unless creating
261 * file and at end of pathname, in which case
262 * we watch for a place to put the new file in
263 * case it doesn't already exist.
264 */
265 ino = 0;
266 i_diroff = dp->i_diroff;
267 slotstatus = FOUND;
268 slotfreespace = slotsize = slotneeded = 0;
269 if ((nameiop == CREATE || nameiop == RENAME) &&
270 (flags & ISLASTCN)) {
271 slotstatus = NONE;
272 slotneeded = DIRECTSIZ(cnp->cn_namelen);
273 }
274
275 #ifdef UFS_DIRHASH
276 /*
277 * Use dirhash for fast operations on large directories. The logic
278 * to determine whether to hash the directory is contained within
279 * ufsdirhash_build(); a zero return means that it decided to hash
280 * this directory and it successfully built up the hash table.
281 */
282 if (ufsdirhash_build(dp) == 0) {
283 /* Look for a free slot if needed. */
284 enduseful = dp->i_size;
285 if (slotstatus != FOUND) {
286 slotoffset = ufsdirhash_findfree(dp, slotneeded,
287 &slotsize);
288 if (slotoffset >= 0) {
289 slotstatus = COMPACT;
290 enduseful = ufsdirhash_enduseful(dp);
291 if (enduseful < 0)
292 enduseful = dp->i_size;
293 }
294 }
295 /* Look up the component. */
296 numdirpasses = 1;
297 entryoffsetinblock = 0; /* silence compiler warning */
298 switch (ufsdirhash_lookup(dp, cnp->cn_nameptr, cnp->cn_namelen,
299 &i_offset, &bp, nameiop == DELETE ? &prevoff : NULL)) {
300 case 0:
301 ep = (struct direct *)((char *)bp->b_data +
302 (i_offset & bmask));
303 goto foundentry;
304 case ENOENT:
305 i_offset = roundup2(dp->i_size, DIRBLKSIZ);
306 goto notfound;
307 default:
308 /* Something failed; just do a linear search. */
309 break;
310 }
311 }
312 #endif /* UFS_DIRHASH */
313 /*
314 * If there is cached information on a previous search of
315 * this directory, pick up where we last left off.
316 * We cache only lookups as these are the most common
317 * and have the greatest payoff. Caching CREATE has little
318 * benefit as it usually must search the entire directory
319 * to determine that the entry does not exist. Caching the
320 * location of the last DELETE or RENAME has not reduced
321 * profiling time and hence has been removed in the interest
322 * of simplicity.
323 */
324 if (nameiop != LOOKUP || i_diroff == 0 || i_diroff >= dp->i_size) {
325 entryoffsetinblock = 0;
326 i_offset = 0;
327 numdirpasses = 1;
328 } else {
329 i_offset = i_diroff;
330 if ((entryoffsetinblock = i_offset & bmask) &&
331 (error = UFS_BLKATOFF(vdp, (off_t)i_offset, NULL, &bp)))
332 return (error);
333 numdirpasses = 2;
334 nchstats.ncs_2passes++;
335 }
336 prevoff = i_offset;
337 endsearch = roundup2(dp->i_size, DIRBLKSIZ);
338 enduseful = 0;
339
340 searchloop:
341 while (i_offset < endsearch) {
342 /*
343 * If necessary, get the next directory block.
344 */
345 if ((i_offset & bmask) == 0) {
346 if (bp != NULL)
347 brelse(bp);
348 error =
349 UFS_BLKATOFF(vdp, (off_t)i_offset, NULL, &bp);
350 if (error)
351 return (error);
352 entryoffsetinblock = 0;
353 }
354 /*
355 * If still looking for a slot, and at a DIRBLKSIZE
356 * boundary, have to start looking for free space again.
357 */
358 if (slotstatus == NONE &&
359 (entryoffsetinblock & (DIRBLKSIZ - 1)) == 0) {
360 slotoffset = -1;
361 slotfreespace = 0;
362 }
363 /*
364 * Get pointer to next entry.
365 * Full validation checks are slow, so we only check
366 * enough to insure forward progress through the
367 * directory. Complete checks can be run by patching
368 * "dirchk" to be true.
369 */
370 ep = (struct direct *)((char *)bp->b_data + entryoffsetinblock);
371 if (ep->d_reclen == 0 || ep->d_reclen >
372 DIRBLKSIZ - (entryoffsetinblock & (DIRBLKSIZ - 1)) ||
373 (dirchk && ufs_dirbadentry(vdp, ep, entryoffsetinblock))) {
374 int i;
375
376 ufs_dirbad(dp, i_offset, "mangled entry");
377 i = DIRBLKSIZ - (entryoffsetinblock & (DIRBLKSIZ - 1));
378 i_offset += i;
379 entryoffsetinblock += i;
380 continue;
381 }
382
383 /*
384 * If an appropriate sized slot has not yet been found,
385 * check to see if one is available. Also accumulate space
386 * in the current block so that we can determine if
387 * compaction is viable.
388 */
389 if (slotstatus != FOUND) {
390 int size = ep->d_reclen;
391
392 if (ep->d_ino != 0)
393 size -= DIRSIZ(OFSFMT(vdp), ep);
394 if (size > 0) {
395 if (size >= slotneeded) {
396 slotstatus = FOUND;
397 slotoffset = i_offset;
398 slotsize = ep->d_reclen;
399 } else if (slotstatus == NONE) {
400 slotfreespace += size;
401 if (slotoffset == -1)
402 slotoffset = i_offset;
403 if (slotfreespace >= slotneeded) {
404 slotstatus = COMPACT;
405 slotsize = i_offset +
406 ep->d_reclen - slotoffset;
407 }
408 }
409 }
410 }
411
412 /*
413 * Check for a name match.
414 */
415 if (ep->d_ino) {
416 # if (BYTE_ORDER == LITTLE_ENDIAN)
417 if (OFSFMT(vdp))
418 namlen = ep->d_type;
419 else
420 namlen = ep->d_namlen;
421 # else
422 namlen = ep->d_namlen;
423 # endif
424 if (namlen == cnp->cn_namelen &&
425 (cnp->cn_nameptr[0] == ep->d_name[0]) &&
426 !bcmp(cnp->cn_nameptr, ep->d_name,
427 (unsigned)namlen)) {
428 #ifdef UFS_DIRHASH
429 foundentry:
430 #endif
431 /*
432 * Save directory entry's inode number and
433 * reclen in ndp->ni_ufs area, and release
434 * directory buffer.
435 */
436 if (!OFSFMT(vdp) && ep->d_type == DT_WHT) {
437 slotstatus = FOUND;
438 slotoffset = i_offset;
439 slotsize = ep->d_reclen;
440 enduseful = dp->i_size;
441 cnp->cn_flags |= ISWHITEOUT;
442 numdirpasses--;
443 goto notfound;
444 }
445 ino = ep->d_ino;
446 goto found;
447 }
448 }
449 prevoff = i_offset;
450 i_offset += ep->d_reclen;
451 entryoffsetinblock += ep->d_reclen;
452 if (ep->d_ino)
453 enduseful = i_offset;
454 }
455 notfound:
456 /*
457 * If we started in the middle of the directory and failed
458 * to find our target, we must check the beginning as well.
459 */
460 if (numdirpasses == 2) {
461 numdirpasses--;
462 i_offset = 0;
463 endsearch = i_diroff;
464 goto searchloop;
465 }
466 if (bp != NULL)
467 brelse(bp);
468 /*
469 * If creating, and at end of pathname and current
470 * directory has not been removed, then can consider
471 * allowing file to be created.
472 */
473 if ((nameiop == CREATE || nameiop == RENAME ||
474 (nameiop == DELETE &&
475 (cnp->cn_flags & DOWHITEOUT) &&
476 (cnp->cn_flags & ISWHITEOUT))) &&
477 (flags & ISLASTCN) && dp->i_effnlink != 0) {
478 /*
479 * Access for write is interpreted as allowing
480 * creation of files in the directory.
481 *
482 * XXX: Fix the comment above.
483 */
484 if (flags & WILLBEDIR)
485 error = VOP_ACCESSX(vdp, VWRITE | VAPPEND, cred, curthread);
486 else
487 error = VOP_ACCESS(vdp, VWRITE, cred, curthread);
488 if (error)
489 return (error);
490 /*
491 * Return an indication of where the new directory
492 * entry should be put. If we didn't find a slot,
493 * then set dp->i_count to 0 indicating
494 * that the new slot belongs at the end of the
495 * directory. If we found a slot, then the new entry
496 * can be put in the range from dp->i_offset to
497 * dp->i_offset + dp->i_count.
498 */
499 if (slotstatus == NONE) {
500 SET_I_OFFSET(dp, roundup2(dp->i_size, DIRBLKSIZ));
501 SET_I_COUNT(dp, 0);
502 enduseful = I_OFFSET(dp);
503 } else if (nameiop == DELETE) {
504 SET_I_OFFSET(dp, slotoffset);
505 if ((I_OFFSET(dp) & (DIRBLKSIZ - 1)) == 0)
506 SET_I_COUNT(dp, 0);
507 else
508 SET_I_COUNT(dp, I_OFFSET(dp) - prevoff);
509 } else {
510 SET_I_OFFSET(dp, slotoffset);
511 SET_I_COUNT(dp, slotsize);
512 if (enduseful < slotoffset + slotsize)
513 enduseful = slotoffset + slotsize;
514 }
515 SET_I_ENDOFF(dp, roundup2(enduseful, DIRBLKSIZ));
516 /*
517 * We return with the directory locked, so that
518 * the parameters we set up above will still be
519 * valid if we actually decide to do a direnter().
520 * We return ni_vp == NULL to indicate that the entry
521 * does not currently exist; we leave a pointer to
522 * the (locked) directory inode in ndp->ni_dvp.
523 *
524 * NB - if the directory is unlocked, then this
525 * information cannot be used.
526 */
527 return (EJUSTRETURN);
528 }
529 /*
530 * Insert name into cache (as non-existent) if appropriate.
531 */
532 if ((cnp->cn_flags & MAKEENTRY) != 0)
533 cache_enter(vdp, NULL, cnp);
534 return (ENOENT);
535
536 found:
537 if (dd_ino != NULL)
538 *dd_ino = ino;
539 if (numdirpasses == 2)
540 nchstats.ncs_pass2++;
541 /*
542 * Check that directory length properly reflects presence
543 * of this entry.
544 */
545 if (i_offset + DIRSIZ(OFSFMT(vdp), ep) > dp->i_size) {
546 ufs_dirbad(dp, i_offset, "i_size too small");
547 brelse(bp);
548 return (EIO);
549 }
550 brelse(bp);
551
552 /*
553 * Found component in pathname.
554 * If the final component of path name, save information
555 * in the cache as to where the entry was found.
556 */
557 if ((flags & ISLASTCN) && nameiop == LOOKUP)
558 dp->i_diroff = rounddown2(i_offset, DIRBLKSIZ);
559
560 /*
561 * If deleting, and at end of pathname, return
562 * parameters which can be used to remove file.
563 */
564 if (nameiop == DELETE && (flags & ISLASTCN)) {
565 if (flags & LOCKPARENT)
566 ASSERT_VOP_ELOCKED(vdp, __FUNCTION__);
567
568 if (VOP_ISLOCKED(vdp) == LK_EXCLUSIVE) {
569 /*
570 * Return pointer to current entry in
571 * dp->i_offset, and distance past previous
572 * entry (if there is a previous entry in this
573 * block) in dp->i_count.
574 *
575 * We shouldn't be setting these in the
576 * WANTPARENT case (first lookup in rename()), but any
577 * lookups that will result in directory changes will
578 * overwrite these.
579 */
580 SET_I_OFFSET(dp, i_offset);
581 if ((I_OFFSET(dp) & (DIRBLKSIZ - 1)) == 0)
582 SET_I_COUNT(dp, 0);
583 else
584 SET_I_COUNT(dp, I_OFFSET(dp) - prevoff);
585 }
586 if (dd_ino != NULL)
587 return (0);
588
589 /*
590 * Save directory inode pointer in ndp->ni_dvp for
591 * dirremove().
592 */
593 if ((error = VFS_VGET(vdp->v_mount, ino,
594 LK_EXCLUSIVE, &tdp)) != 0)
595 return (error);
596 error = ufs_delete_denied(vdp, tdp, cred, curthread);
597 if (error) {
598 vput(tdp);
599 return (error);
600 }
601 if (dp->i_number == ino) {
602 VREF(vdp);
603 *vpp = vdp;
604 vput(tdp);
605 return (0);
606 }
607
608 *vpp = tdp;
609 return (0);
610 }
611
612 /*
613 * If rewriting (RENAME), return the inode and the
614 * information required to rewrite the present directory
615 * Must get inode of directory entry to verify it's a
616 * regular file, or empty directory.
617 */
618 if (nameiop == RENAME && (flags & ISLASTCN)) {
619 if (flags & WILLBEDIR)
620 error = VOP_ACCESSX(vdp, VWRITE | VAPPEND, cred, curthread);
621 else
622 error = VOP_ACCESS(vdp, VWRITE, cred, curthread);
623 if (error)
624 return (error);
625 /*
626 * Careful about locking second inode.
627 * This can only occur if the target is ".".
628 */
629 SET_I_OFFSET(dp, i_offset);
630 if (dp->i_number == ino)
631 return (EISDIR);
632 if (dd_ino != NULL)
633 return (0);
634 if ((error = VFS_VGET(vdp->v_mount, ino,
635 LK_EXCLUSIVE, &tdp)) != 0)
636 return (error);
637
638 error = ufs_delete_denied(vdp, tdp, cred, curthread);
639 if (error) {
640 vput(tdp);
641 return (error);
642 }
643
644 #ifdef SunOS_doesnt_do_that
645 /*
646 * The only purpose of this check is to return the correct
647 * error. Assume that we want to rename directory "a"
648 * to a file "b", and that we have no ACL_WRITE_DATA on
649 * a containing directory, but we _do_ have ACL_APPEND_DATA.
650 * In that case, the VOP_ACCESS check above will return 0,
651 * and the operation will fail with ENOTDIR instead
652 * of EACCESS.
653 */
654 if (tdp->v_type == VDIR)
655 error = VOP_ACCESSX(vdp, VWRITE | VAPPEND, cred, curthread);
656 else
657 error = VOP_ACCESS(vdp, VWRITE, cred, curthread);
658 if (error) {
659 vput(tdp);
660 return (error);
661 }
662 #endif
663
664 *vpp = tdp;
665 return (0);
666 }
667 if (dd_ino != NULL)
668 return (0);
669
670 /*
671 * Step through the translation in the name. We do not `vput' the
672 * directory because we may need it again if a symbolic link
673 * is relative to the current directory. Instead we save it
674 * unlocked as "pdp". We must get the target inode before unlocking
675 * the directory to insure that the inode will not be removed
676 * before we get it. We prevent deadlock by always fetching
677 * inodes from the root, moving down the directory tree. Thus
678 * when following backward pointers ".." we must unlock the
679 * parent directory before getting the requested directory.
680 * There is a potential race condition here if both the current
681 * and parent directories are removed before the VFS_VGET for the
682 * inode associated with ".." returns. We hope that this occurs
683 * infrequently since we cannot avoid this race condition without
684 * implementing a sophisticated deadlock detection algorithm.
685 * Note also that this simple deadlock detection scheme will not
686 * work if the filesystem has any hard links other than ".."
687 * that point backwards in the directory structure.
688 */
689 pdp = vdp;
690 if (flags & ISDOTDOT) {
691 error = vn_vget_ino(pdp, ino, cnp->cn_lkflags, &tdp);
692 if (error)
693 return (error);
694
695 /*
696 * Recheck that ".." entry in the vdp directory points
697 * to the inode we looked up before vdp lock was
698 * dropped.
699 */
700 error = ufs_lookup_ino(pdp, NULL, cnp, &ino1);
701 if (error) {
702 vput(tdp);
703 return (error);
704 }
705 if (ino1 != ino) {
706 vput(tdp);
707 goto restart;
708 }
709
710 *vpp = tdp;
711 } else if (dp->i_number == ino) {
712 VREF(vdp); /* we want ourself, ie "." */
713 /*
714 * When we lookup "." we still can be asked to lock it
715 * differently.
716 */
717 ltype = cnp->cn_lkflags & LK_TYPE_MASK;
718 if (ltype != VOP_ISLOCKED(vdp)) {
719 if (ltype == LK_EXCLUSIVE)
720 vn_lock(vdp, LK_UPGRADE | LK_RETRY);
721 else /* if (ltype == LK_SHARED) */
722 vn_lock(vdp, LK_DOWNGRADE | LK_RETRY);
723 /*
724 * Relock for the "." case may left us with
725 * reclaimed vnode.
726 */
727 if (VN_IS_DOOMED(vdp)) {
728 vrele(vdp);
729 return (ENOENT);
730 }
731 }
732 *vpp = vdp;
733 } else {
734 error = VFS_VGET(pdp->v_mount, ino, cnp->cn_lkflags, &tdp);
735 if (error == 0 && VTOI(tdp)->i_mode == 0) {
736 vgone(tdp);
737 vput(tdp);
738 error = ENOENT;
739 }
740 if (error)
741 return (error);
742 *vpp = tdp;
743 }
744
745 /*
746 * Insert name into cache if appropriate.
747 */
748 if (cnp->cn_flags & MAKEENTRY)
749 cache_enter(vdp, *vpp, cnp);
750 return (0);
751 }
752
753 void
ufs_dirbad(struct inode * ip,doff_t offset,char * how)754 ufs_dirbad(struct inode *ip, doff_t offset, char *how)
755 {
756
757 (void)printf("%s: bad dir ino %ju at offset %ld: %s\n",
758 ITOV(ip)->v_mount->mnt_stat.f_mntonname, (uintmax_t)ip->i_number,
759 (long)offset, how);
760 }
761
762 /*
763 * Do consistency checking on a directory entry:
764 * record length must be multiple of 4
765 * entry must fit in rest of its DIRBLKSIZ block
766 * record must be large enough to contain entry
767 * name is not longer than UFS_MAXNAMLEN
768 * name must be as long as advertised, and null terminated
769 */
770 int
ufs_dirbadentry(struct vnode * dp,struct direct * ep,int entryoffsetinblock)771 ufs_dirbadentry(struct vnode *dp, struct direct *ep, int entryoffsetinblock)
772 {
773 int i, namlen;
774
775 # if (BYTE_ORDER == LITTLE_ENDIAN)
776 if (OFSFMT(dp))
777 namlen = ep->d_type;
778 else
779 namlen = ep->d_namlen;
780 # else
781 namlen = ep->d_namlen;
782 # endif
783 if ((ep->d_reclen & 0x3) != 0 ||
784 ep->d_reclen > DIRBLKSIZ - (entryoffsetinblock & (DIRBLKSIZ - 1)) ||
785 ep->d_reclen < DIRSIZ(OFSFMT(dp), ep) || namlen > UFS_MAXNAMLEN) {
786 /*return (1); */
787 printf("First bad\n");
788 goto bad;
789 }
790 if (ep->d_ino == 0)
791 return (0);
792 for (i = 0; i < namlen; i++)
793 if (ep->d_name[i] == '\0') {
794 /*return (1); */
795 printf("Second bad\n");
796 goto bad;
797 }
798 if (ep->d_name[i])
799 goto bad;
800 return (0);
801 bad:
802 return (1);
803 }
804
805 /*
806 * Construct a new directory entry after a call to namei, using the
807 * parameters that it left in the componentname argument cnp. The
808 * argument ip is the inode to which the new directory entry will refer.
809 */
810 void
ufs_makedirentry(struct inode * ip,struct componentname * cnp,struct direct * newdirp)811 ufs_makedirentry(struct inode *ip, struct componentname *cnp,
812 struct direct *newdirp)
813 {
814 uint64_t namelen;
815
816 namelen = (unsigned)cnp->cn_namelen;
817 KASSERT(namelen <= UFS_MAXNAMLEN,
818 ("ufs_makedirentry: name too long"));
819 newdirp->d_ino = ip->i_number;
820 newdirp->d_namlen = namelen;
821
822 /* Zero out after-name padding */
823 *(uint32_t *)(&newdirp->d_name[namelen & ~(DIR_ROUNDUP - 1)]) = 0;
824
825 bcopy(cnp->cn_nameptr, newdirp->d_name, namelen);
826
827 if (!OFSFMT(ITOV(ip)))
828 newdirp->d_type = IFTODT(ip->i_mode);
829 else {
830 newdirp->d_type = 0;
831 # if (BYTE_ORDER == LITTLE_ENDIAN)
832 { uint8_t tmp = newdirp->d_namlen;
833 newdirp->d_namlen = newdirp->d_type;
834 newdirp->d_type = tmp; }
835 # endif
836 }
837 }
838
839 /*
840 * Write a directory entry after a call to namei, using the parameters
841 * that it left in nameidata. The argument dirp is the new directory
842 * entry contents. Dvp is a pointer to the directory to be written,
843 * which was left locked by namei. Remaining parameters (dp->i_offset,
844 * dp->i_count) indicate how the space for the new entry is to be obtained.
845 * Non-null bp indicates that a directory is being created (for the
846 * soft dependency code).
847 */
848 int
ufs_direnter(struct vnode * dvp,struct vnode * tvp,struct direct * dirp,struct componentname * cnp,struct buf * newdirbp)849 ufs_direnter(struct vnode *dvp, struct vnode *tvp, struct direct *dirp,
850 struct componentname *cnp, struct buf *newdirbp)
851 {
852 struct ucred *cr;
853 struct thread *td;
854 int newentrysize;
855 struct inode *dp;
856 struct buf *bp;
857 uint64_t dsize;
858 struct direct *ep, *nep;
859 uint64_t old_isize;
860 int error, ret, blkoff, loc, spacefree, flags, namlen;
861 char *dirbuf;
862
863 td = curthread; /* XXX */
864 cr = td->td_ucred;
865
866 dp = VTOI(dvp);
867 newentrysize = DIRSIZ(OFSFMT(dvp), dirp);
868
869 if (I_COUNT(dp) == 0) {
870 /*
871 * If dp->i_count is 0, then namei could find no
872 * space in the directory. Here, dp->i_offset will
873 * be on a directory block boundary and we will write the
874 * new entry into a fresh block.
875 */
876 if (I_OFFSET(dp) & (DIRBLKSIZ - 1))
877 panic("ufs_direnter: newblk");
878 flags = BA_CLRBUF;
879 if (!DOINGSOFTDEP(dvp) && !DOINGASYNC(dvp))
880 flags |= IO_SYNC;
881 #ifdef QUOTA
882 if ((error = getinoquota(dp)) != 0) {
883 if (DOINGSOFTDEP(dvp) && newdirbp != NULL)
884 bdwrite(newdirbp);
885 return (error);
886 }
887 #endif
888 old_isize = dp->i_size;
889 vnode_pager_setsize(dvp,
890 (vm_ooffset_t)I_OFFSET(dp) + DIRBLKSIZ);
891 if ((error = UFS_BALLOC(dvp, (off_t)I_OFFSET(dp), DIRBLKSIZ,
892 cr, flags, &bp)) != 0) {
893 if (DOINGSOFTDEP(dvp) && newdirbp != NULL)
894 bdwrite(newdirbp);
895 vnode_pager_setsize(dvp, (vm_ooffset_t)old_isize);
896 return (error);
897 }
898 dp->i_size = I_OFFSET(dp) + DIRBLKSIZ;
899 DIP_SET(dp, i_size, dp->i_size);
900 SET_I_ENDOFF(dp, dp->i_size);
901 UFS_INODE_SET_FLAG(dp, IN_SIZEMOD | IN_CHANGE | IN_UPDATE);
902 dirp->d_reclen = DIRBLKSIZ;
903 blkoff = I_OFFSET(dp) &
904 (VFSTOUFS(dvp->v_mount)->um_mountp->mnt_stat.f_iosize - 1);
905 bcopy((caddr_t)dirp, (caddr_t)bp->b_data + blkoff,newentrysize);
906 #ifdef UFS_DIRHASH
907 if (dp->i_dirhash != NULL) {
908 ufsdirhash_newblk(dp, I_OFFSET(dp));
909 ufsdirhash_add(dp, dirp, I_OFFSET(dp));
910 ufsdirhash_checkblock(dp, (char *)bp->b_data + blkoff,
911 I_OFFSET(dp));
912 }
913 #endif
914 if (DOINGSOFTDEP(dvp)) {
915 /*
916 * Ensure that the entire newly allocated block is a
917 * valid directory so that future growth within the
918 * block does not have to ensure that the block is
919 * written before the inode.
920 */
921 blkoff += DIRBLKSIZ;
922 while (blkoff < bp->b_bcount) {
923 ((struct direct *)
924 (bp->b_data + blkoff))->d_reclen = DIRBLKSIZ;
925 blkoff += DIRBLKSIZ;
926 }
927 if (softdep_setup_directory_add(bp, dp, I_OFFSET(dp),
928 dirp->d_ino, newdirbp, 1))
929 UFS_INODE_SET_FLAG(dp, IN_NEEDSYNC);
930 if (newdirbp)
931 bdwrite(newdirbp);
932 bdwrite(bp);
933 return (UFS_UPDATE(dvp, 0));
934 }
935 if (DOINGASYNC(dvp)) {
936 bdwrite(bp);
937 return (UFS_UPDATE(dvp, 0));
938 }
939 error = bwrite(bp);
940 ret = UFS_UPDATE(dvp, 1);
941 if (error == 0)
942 return (ret);
943 return (error);
944 }
945
946 /*
947 * If dp->i_count is non-zero, then namei found space for the new
948 * entry in the range dp->i_offset to dp->i_offset + dp->i_count
949 * in the directory. To use this space, we may have to compact
950 * the entries located there, by copying them together towards the
951 * beginning of the block, leaving the free space in one usable
952 * chunk at the end.
953 */
954
955 /*
956 * Increase size of directory if entry eats into new space.
957 * This should never push the size past a new multiple of
958 * DIRBLKSIZE.
959 *
960 * N.B. - THIS IS AN ARTIFACT OF 4.2 AND SHOULD NEVER HAPPEN.
961 */
962 if (I_OFFSET(dp) + I_COUNT(dp) > dp->i_size) {
963 dp->i_size = I_OFFSET(dp) + I_COUNT(dp);
964 DIP_SET(dp, i_size, dp->i_size);
965 UFS_INODE_SET_FLAG(dp, IN_SIZEMOD | IN_MODIFIED);
966 }
967 /*
968 * Get the block containing the space for the new directory entry.
969 */
970 error = UFS_BLKATOFF(dvp, (off_t)I_OFFSET(dp), &dirbuf, &bp);
971 if (error) {
972 if (DOINGSOFTDEP(dvp) && newdirbp != NULL)
973 bdwrite(newdirbp);
974 return (error);
975 }
976 /*
977 * Find space for the new entry. In the simple case, the entry at
978 * offset base will have the space. If it does not, then namei
979 * arranged that compacting the region dp->i_offset to
980 * dp->i_offset + dp->i_count would yield the space.
981 */
982 ep = (struct direct *)dirbuf;
983 dsize = ep->d_ino ? DIRSIZ(OFSFMT(dvp), ep) : 0;
984 spacefree = ep->d_reclen - dsize;
985 for (loc = ep->d_reclen; loc < I_COUNT(dp); ) {
986 nep = (struct direct *)(dirbuf + loc);
987
988 /* Trim the existing slot (NB: dsize may be zero). */
989 ep->d_reclen = dsize;
990 ep = (struct direct *)((char *)ep + dsize);
991
992 /* Read nep->d_reclen now as the bcopy() may clobber it. */
993 loc += nep->d_reclen;
994 if (nep->d_ino == 0) {
995 /*
996 * A mid-block unused entry. Such entries are
997 * never created by the kernel, but fsck_ffs
998 * can create them (and it doesn't fix them).
999 *
1000 * Add up the free space, and initialise the
1001 * relocated entry since we don't bcopy it.
1002 */
1003 spacefree += nep->d_reclen;
1004 ep->d_ino = 0;
1005 dsize = 0;
1006 continue;
1007 }
1008 dsize = DIRSIZ(OFSFMT(dvp), nep);
1009 spacefree += nep->d_reclen - dsize;
1010 #ifdef UFS_DIRHASH
1011 if (dp->i_dirhash != NULL)
1012 ufsdirhash_move(dp, nep,
1013 I_OFFSET(dp) + ((char *)nep - dirbuf),
1014 I_OFFSET(dp) + ((char *)ep - dirbuf));
1015 #endif
1016 if (DOINGSOFTDEP(dvp))
1017 softdep_change_directoryentry_offset(bp, dp, dirbuf,
1018 (caddr_t)nep, (caddr_t)ep, dsize);
1019 else
1020 bcopy((caddr_t)nep, (caddr_t)ep, dsize);
1021 }
1022 /*
1023 * Here, `ep' points to a directory entry containing `dsize' in-use
1024 * bytes followed by `spacefree' unused bytes. If ep->d_ino == 0,
1025 * then the entry is completely unused (dsize == 0). The value
1026 * of ep->d_reclen is always indeterminate.
1027 *
1028 * Update the pointer fields in the previous entry (if any),
1029 * copy in the new entry, and write out the block.
1030 */
1031 # if (BYTE_ORDER == LITTLE_ENDIAN)
1032 if (OFSFMT(dvp))
1033 namlen = ep->d_type;
1034 else
1035 namlen = ep->d_namlen;
1036 # else
1037 namlen = ep->d_namlen;
1038 # endif
1039 if (ep->d_ino == 0 ||
1040 (ep->d_ino == UFS_WINO && namlen == dirp->d_namlen &&
1041 bcmp(ep->d_name, dirp->d_name, dirp->d_namlen) == 0)) {
1042 if (spacefree + dsize < newentrysize)
1043 panic("ufs_direnter: compact1");
1044 dirp->d_reclen = spacefree + dsize;
1045 } else {
1046 if (spacefree < newentrysize)
1047 panic("ufs_direnter: compact2");
1048 dirp->d_reclen = spacefree;
1049 ep->d_reclen = dsize;
1050 ep = (struct direct *)((char *)ep + dsize);
1051 }
1052 #ifdef UFS_DIRHASH
1053 if (dp->i_dirhash != NULL && (ep->d_ino == 0 ||
1054 dirp->d_reclen == spacefree))
1055 ufsdirhash_add(dp, dirp, I_OFFSET(dp) + ((char *)ep - dirbuf));
1056 #endif
1057 bcopy((caddr_t)dirp, (caddr_t)ep, (uint64_t)newentrysize);
1058 #ifdef UFS_DIRHASH
1059 if (dp->i_dirhash != NULL)
1060 ufsdirhash_checkblock(dp, dirbuf -
1061 (I_OFFSET(dp) & (DIRBLKSIZ - 1)),
1062 rounddown2(I_OFFSET(dp), DIRBLKSIZ));
1063 #endif
1064
1065 if (DOINGSOFTDEP(dvp)) {
1066 (void) softdep_setup_directory_add(bp, dp,
1067 I_OFFSET(dp) + (caddr_t)ep - dirbuf,
1068 dirp->d_ino, newdirbp, 0);
1069 if (newdirbp != NULL)
1070 bdwrite(newdirbp);
1071 bdwrite(bp);
1072 } else {
1073 if (DOINGASYNC(dvp)) {
1074 bdwrite(bp);
1075 error = 0;
1076 } else {
1077 error = bwrite(bp);
1078 }
1079 }
1080
1081 /*
1082 * If all went well, and the directory can be shortened,
1083 * mark directory inode with the truncation request.
1084 */
1085 UFS_INODE_SET_FLAG(dp, IN_CHANGE | IN_UPDATE | (error == 0 &&
1086 I_ENDOFF(dp) != 0 && I_ENDOFF(dp) < dp->i_size ? IN_ENDOFF : 0));
1087
1088 return (error);
1089 }
1090
1091 /*
1092 * Remove a directory entry after a call to namei, using
1093 * the parameters which it left in nameidata. The entry
1094 * dp->i_offset contains the offset into the directory of the
1095 * entry to be eliminated. The dp->i_count field contains the
1096 * size of the previous record in the directory. If this
1097 * is 0, the first entry is being deleted, so we need only
1098 * zero the inode number to mark the entry as free. If the
1099 * entry is not the first in the directory, we must reclaim
1100 * the space of the now empty record by adding the record size
1101 * to the size of the previous entry.
1102 */
1103 int
ufs_dirremove(struct vnode * dvp,struct inode * ip,int flags,int isrmdir)1104 ufs_dirremove(struct vnode *dvp, struct inode *ip, int flags, int isrmdir)
1105 {
1106 struct inode *dp;
1107 struct direct *ep, *rep;
1108 struct buf *bp;
1109 off_t offset;
1110 int error;
1111
1112 dp = VTOI(dvp);
1113
1114 /*
1115 * Adjust the link count early so softdep can block if necessary.
1116 */
1117 if (ip) {
1118 ip->i_effnlink--;
1119 UFS_INODE_SET_FLAG(ip, IN_CHANGE);
1120 if (DOINGSOFTDEP(dvp)) {
1121 softdep_setup_unlink(dp, ip);
1122 } else {
1123 ip->i_nlink--;
1124 DIP_SET_NLINK(ip, ip->i_nlink);
1125 UFS_INODE_SET_FLAG(ip, IN_CHANGE);
1126 }
1127 }
1128 if (flags & DOWHITEOUT)
1129 offset = I_OFFSET(dp);
1130 else
1131 offset = I_OFFSET(dp) - I_COUNT(dp);
1132 if ((error = UFS_BLKATOFF(dvp, offset, (char **)&ep, &bp)) != 0) {
1133 if (ip) {
1134 ip->i_effnlink++;
1135 UFS_INODE_SET_FLAG(ip, IN_CHANGE);
1136 if (DOINGSOFTDEP(dvp)) {
1137 softdep_change_linkcnt(ip);
1138 } else {
1139 ip->i_nlink++;
1140 DIP_SET_NLINK(ip, ip->i_nlink);
1141 UFS_INODE_SET_FLAG(ip, IN_CHANGE);
1142 }
1143 }
1144 return (error);
1145 }
1146 if (flags & DOWHITEOUT) {
1147 /*
1148 * Whiteout entry: set d_ino to UFS_WINO.
1149 */
1150 ep->d_ino = UFS_WINO;
1151 ep->d_type = DT_WHT;
1152 goto out;
1153 }
1154 /* Set 'rep' to the entry being removed. */
1155 if (I_COUNT(dp) == 0)
1156 rep = ep;
1157 else
1158 rep = (struct direct *)((char *)ep + ep->d_reclen);
1159 #ifdef UFS_DIRHASH
1160 /*
1161 * Remove the dirhash entry. This is complicated by the fact
1162 * that `ep' is the previous entry when dp->i_count != 0.
1163 */
1164 if (dp->i_dirhash != NULL)
1165 ufsdirhash_remove(dp, rep, I_OFFSET(dp));
1166 #endif
1167 if (ip && rep->d_ino != ip->i_number)
1168 panic("ufs_dirremove: ip %ju does not match dirent ino %ju\n",
1169 (uintmax_t)ip->i_number, (uintmax_t)rep->d_ino);
1170 /*
1171 * Zero out the file directory entry metadata to reduce disk
1172 * scavenging disclosure.
1173 */
1174 bzero(&rep->d_name[0], rep->d_namlen);
1175 rep->d_namlen = 0;
1176 rep->d_type = 0;
1177 rep->d_ino = 0;
1178
1179 if (I_COUNT(dp) != 0) {
1180 /*
1181 * Collapse new free space into previous entry.
1182 */
1183 ep->d_reclen += rep->d_reclen;
1184 rep->d_reclen = 0;
1185 }
1186 #ifdef UFS_DIRHASH
1187 if (dp->i_dirhash != NULL)
1188 ufsdirhash_checkblock(dp, (char *)ep -
1189 ((I_OFFSET(dp) - I_COUNT(dp)) & (DIRBLKSIZ - 1)),
1190 rounddown2(I_OFFSET(dp), DIRBLKSIZ));
1191 #endif
1192 out:
1193 error = 0;
1194 if (DOINGSOFTDEP(dvp)) {
1195 if (ip)
1196 softdep_setup_remove(bp, dp, ip, isrmdir);
1197 if (softdep_slowdown(dvp))
1198 error = bwrite(bp);
1199 else
1200 bdwrite(bp);
1201 } else {
1202 if (flags & DOWHITEOUT)
1203 error = bwrite(bp);
1204 else if (DOINGASYNC(dvp))
1205 bdwrite(bp);
1206 else
1207 error = bwrite(bp);
1208 }
1209 UFS_INODE_SET_FLAG(dp, IN_CHANGE | IN_UPDATE);
1210 /*
1211 * If the last named reference to a snapshot goes away,
1212 * drop its snapshot reference so that it will be reclaimed
1213 * when last open reference goes away.
1214 */
1215 if (ip != NULL && IS_SNAPSHOT(ip) && ip->i_effnlink == 0)
1216 UFS_SNAPGONE(ip);
1217 return (error);
1218 }
1219
1220 /*
1221 * Rewrite an existing directory entry to point at the inode
1222 * supplied. The parameters describing the directory entry are
1223 * set up by a call to namei.
1224 */
1225 int
ufs_dirrewrite(struct inode * dp,struct inode * oip,ino_t newinum,int newtype,int isrmdir)1226 ufs_dirrewrite(struct inode *dp, struct inode *oip, ino_t newinum, int newtype,
1227 int isrmdir)
1228 {
1229 struct buf *bp;
1230 struct direct *ep;
1231 struct vnode *vdp = ITOV(dp);
1232 int error;
1233
1234 /*
1235 * Drop the link before we lock the buf so softdep can block if
1236 * necessary.
1237 */
1238 oip->i_effnlink--;
1239 UFS_INODE_SET_FLAG(oip, IN_CHANGE);
1240 if (DOINGSOFTDEP(vdp)) {
1241 softdep_setup_unlink(dp, oip);
1242 } else {
1243 oip->i_nlink--;
1244 DIP_SET_NLINK(oip, oip->i_nlink);
1245 UFS_INODE_SET_FLAG(oip, IN_CHANGE);
1246 }
1247
1248 error = UFS_BLKATOFF(vdp, (off_t)I_OFFSET(dp), (char **)&ep, &bp);
1249 if (error == 0 && ep->d_namlen == 2 && ep->d_name[1] == '.' &&
1250 ep->d_name[0] == '.' && ep->d_ino != oip->i_number) {
1251 brelse(bp);
1252 error = EIDRM;
1253 }
1254 if (error) {
1255 oip->i_effnlink++;
1256 UFS_INODE_SET_FLAG(oip, IN_CHANGE);
1257 if (DOINGSOFTDEP(vdp)) {
1258 softdep_change_linkcnt(oip);
1259 } else {
1260 oip->i_nlink++;
1261 DIP_SET_NLINK(oip, oip->i_nlink);
1262 UFS_INODE_SET_FLAG(oip, IN_CHANGE);
1263 }
1264 return (error);
1265 }
1266 ep->d_ino = newinum;
1267 if (!OFSFMT(vdp))
1268 ep->d_type = newtype;
1269 if (DOINGSOFTDEP(vdp)) {
1270 softdep_setup_directory_change(bp, dp, oip, newinum, isrmdir);
1271 bdwrite(bp);
1272 } else {
1273 if (DOINGASYNC(vdp)) {
1274 bdwrite(bp);
1275 error = 0;
1276 } else {
1277 error = bwrite(bp);
1278 }
1279 }
1280 UFS_INODE_SET_FLAG(dp, IN_CHANGE | IN_UPDATE);
1281 /*
1282 * If the last named reference to a snapshot goes away,
1283 * drop its snapshot reference so that it will be reclaimed
1284 * when last open reference goes away.
1285 */
1286 if (IS_SNAPSHOT(oip) && oip->i_effnlink == 0)
1287 UFS_SNAPGONE(oip);
1288 return (error);
1289 }
1290
1291 /*
1292 * Check if a directory is empty or not.
1293 * Inode supplied must be locked.
1294 *
1295 * Using a struct dirtemplate here is not precisely
1296 * what we want, but better than using a struct direct.
1297 *
1298 * NB: does not handle corrupted directories.
1299 */
1300 int
ufs_dirempty(struct inode * ip,ino_t parentino,struct ucred * cred,int skipwhiteout)1301 ufs_dirempty(struct inode *ip, ino_t parentino, struct ucred *cred,
1302 int skipwhiteout)
1303 {
1304 doff_t off;
1305 struct dirtemplate dbuf;
1306 struct direct *dp = (struct direct *)&dbuf;
1307 int error, namlen;
1308 ssize_t count;
1309 #define MINDIRSIZ (sizeof (struct dirtemplate) / 2)
1310
1311 for (off = 0; off < ip->i_size; off += dp->d_reclen) {
1312 error = vn_rdwr(UIO_READ, ITOV(ip), (caddr_t)dp, MINDIRSIZ,
1313 off, UIO_SYSSPACE, IO_NODELOCKED | IO_NOMACCHECK, cred,
1314 NOCRED, &count, (struct thread *)0);
1315 /*
1316 * Since we read MINDIRSIZ, residual must
1317 * be 0 unless we're at end of file.
1318 */
1319 if (error || count != 0)
1320 return (0);
1321 /* avoid infinite loops */
1322 if (dp->d_reclen == 0)
1323 return (0);
1324 /* skip empty entries */
1325 if (dp->d_ino == 0 ||
1326 (skipwhiteout != 0 && dp->d_ino == UFS_WINO))
1327 continue;
1328 /* accept only "." and ".." */
1329 # if (BYTE_ORDER == LITTLE_ENDIAN)
1330 if (OFSFMT(ITOV(ip)))
1331 namlen = dp->d_type;
1332 else
1333 namlen = dp->d_namlen;
1334 # else
1335 namlen = dp->d_namlen;
1336 # endif
1337 if (namlen > 2)
1338 return (0);
1339 if (dp->d_name[0] != '.')
1340 return (0);
1341 /*
1342 * At this point namlen must be 1 or 2.
1343 * 1 implies ".", 2 implies ".." if second
1344 * char is also "."
1345 */
1346 if (namlen == 1 && dp->d_ino == ip->i_number)
1347 continue;
1348 if (dp->d_name[1] == '.' && dp->d_ino == parentino)
1349 continue;
1350 return (0);
1351 }
1352 return (1);
1353 }
1354
1355 static int
ufs_dir_dd_ino(struct vnode * vp,struct ucred * cred,ino_t * dd_ino,struct vnode ** dd_vp)1356 ufs_dir_dd_ino(struct vnode *vp, struct ucred *cred, ino_t *dd_ino,
1357 struct vnode **dd_vp)
1358 {
1359 struct dirtemplate dirbuf;
1360 struct vnode *ddvp;
1361 int error, namlen;
1362
1363 ASSERT_VOP_LOCKED(vp, "ufs_dir_dd_ino");
1364 *dd_vp = NULL;
1365 if (vp->v_type != VDIR)
1366 return (ENOTDIR);
1367 /*
1368 * First check to see if we have it in the name cache.
1369 */
1370 if ((ddvp = vn_dir_dd_ino(vp)) != NULL) {
1371 KASSERT(ddvp->v_mount == vp->v_mount,
1372 ("ufs_dir_dd_ino: Unexpected mount point crossing"));
1373 *dd_ino = VTOI(ddvp)->i_number;
1374 *dd_vp = ddvp;
1375 return (0);
1376 }
1377 /*
1378 * Have to read the directory.
1379 */
1380 error = vn_rdwr(UIO_READ, vp, (caddr_t)&dirbuf,
1381 sizeof (struct dirtemplate), (off_t)0, UIO_SYSSPACE,
1382 IO_NODELOCKED | IO_NOMACCHECK, cred, NOCRED, NULL, NULL);
1383 if (error != 0)
1384 return (error);
1385 #if (BYTE_ORDER == LITTLE_ENDIAN)
1386 if (OFSFMT(vp))
1387 namlen = dirbuf.dotdot_type;
1388 else
1389 namlen = dirbuf.dotdot_namlen;
1390 #else
1391 namlen = dirbuf.dotdot_namlen;
1392 #endif
1393 if (namlen != 2 || dirbuf.dotdot_name[0] != '.' ||
1394 dirbuf.dotdot_name[1] != '.')
1395 return (ENOTDIR);
1396 *dd_ino = dirbuf.dotdot_ino;
1397 return (0);
1398 }
1399
1400 /*
1401 * Check if source directory is in the path of the target directory.
1402 */
1403 int
ufs_checkpath(ino_t source_ino,ino_t parent_ino,struct inode * target,struct ucred * cred,ino_t * wait_ino)1404 ufs_checkpath(ino_t source_ino, ino_t parent_ino, struct inode *target,
1405 struct ucred *cred, ino_t *wait_ino)
1406 {
1407 struct mount *mp;
1408 struct vnode *tvp, *vp, *vp1;
1409 int error;
1410 ino_t dd_ino;
1411
1412 vp = tvp = ITOV(target);
1413 mp = vp->v_mount;
1414 *wait_ino = 0;
1415 sx_assert(&VFSTOUFS(mp)->um_checkpath_lock, SA_XLOCKED);
1416
1417 if (target->i_number == source_ino)
1418 return (EEXIST);
1419 if (target->i_number == parent_ino)
1420 return (0);
1421 if (target->i_number == UFS_ROOTINO)
1422 return (0);
1423 for (;;) {
1424 error = ufs_dir_dd_ino(vp, cred, &dd_ino, &vp1);
1425 if (error != 0)
1426 break;
1427 if (dd_ino == source_ino) {
1428 error = EINVAL;
1429 break;
1430 }
1431 if (dd_ino == UFS_ROOTINO)
1432 break;
1433 if (dd_ino == parent_ino)
1434 break;
1435 if (vp1 == NULL) {
1436 error = VFS_VGET(mp, dd_ino, LK_SHARED | LK_NOWAIT,
1437 &vp1);
1438 if (error != 0) {
1439 *wait_ino = dd_ino;
1440 break;
1441 }
1442 }
1443 KASSERT(dd_ino == VTOI(vp1)->i_number,
1444 ("directory %ju reparented\n",
1445 (uintmax_t)VTOI(vp1)->i_number));
1446 if (vp != tvp)
1447 vput(vp);
1448 vp = vp1;
1449 }
1450
1451 if (error == ENOTDIR)
1452 panic("checkpath: .. not a directory\n");
1453 if (vp1 != NULL)
1454 vput(vp1);
1455 if (vp != tvp)
1456 vput(vp);
1457 return (error);
1458 }
1459
1460 #ifdef DIAGNOSTIC
1461 static void
ufs_assert_inode_offset_owner(struct inode * ip,struct iown_tracker * tr,const char * name,const char * file,int line)1462 ufs_assert_inode_offset_owner(struct inode *ip, struct iown_tracker *tr,
1463 const char *name, const char *file, int line)
1464 {
1465 char msg[128];
1466
1467 snprintf(msg, sizeof(msg), "at %s@%d", file, line);
1468 ASSERT_VOP_ELOCKED(ITOV(ip), msg);
1469 MPASS((ip->i_mode & IFMT) == IFDIR);
1470 if (curthread == tr->tr_owner && ip->i_lock_gen == tr->tr_gen)
1471 return;
1472 printf("locked at\n");
1473 stack_print(&tr->tr_st);
1474 printf("unlocked at\n");
1475 stack_print(&tr->tr_unlock);
1476 panic("%s ip %p %jd offset owner %p %d gen %d "
1477 "curthread %p %d gen %d at %s@%d\n",
1478 name, ip, (uintmax_t)ip->i_number, tr->tr_owner,
1479 tr->tr_owner->td_tid, tr->tr_gen,
1480 curthread, curthread->td_tid, ip->i_lock_gen,
1481 file, line);
1482 }
1483
1484 static void
ufs_set_inode_offset_owner(struct inode * ip,struct iown_tracker * tr,const char * file,int line)1485 ufs_set_inode_offset_owner(struct inode *ip, struct iown_tracker *tr,
1486 const char *file, int line)
1487 {
1488 char msg[128];
1489
1490 snprintf(msg, sizeof(msg), "at %s@%d", file, line);
1491 ASSERT_VOP_ELOCKED(ITOV(ip), msg);
1492 MPASS((ip->i_mode & IFMT) == IFDIR);
1493 tr->tr_owner = curthread;
1494 tr->tr_gen = ip->i_lock_gen;
1495 stack_save(&tr->tr_st);
1496 }
1497
1498 static void
ufs_init_one_tracker(struct iown_tracker * tr)1499 ufs_init_one_tracker(struct iown_tracker *tr)
1500 {
1501 tr->tr_owner = NULL;
1502 stack_zero(&tr->tr_st);
1503 }
1504
1505 void
ufs_init_trackers(struct inode * ip)1506 ufs_init_trackers(struct inode *ip)
1507 {
1508 ufs_init_one_tracker(&ip->i_offset_tracker);
1509 ufs_init_one_tracker(&ip->i_count_tracker);
1510 ufs_init_one_tracker(&ip->i_endoff_tracker);
1511 }
1512
1513 void
ufs_unlock_tracker(struct inode * ip)1514 ufs_unlock_tracker(struct inode *ip)
1515 {
1516 if (ip->i_count_tracker.tr_gen == ip->i_lock_gen)
1517 stack_save(&ip->i_count_tracker.tr_unlock);
1518 if (ip->i_offset_tracker.tr_gen == ip->i_lock_gen)
1519 stack_save(&ip->i_offset_tracker.tr_unlock);
1520 if (ip->i_endoff_tracker.tr_gen == ip->i_lock_gen)
1521 stack_save(&ip->i_endoff_tracker.tr_unlock);
1522 ip->i_lock_gen++;
1523 }
1524
1525 doff_t
ufs_get_i_offset(struct inode * ip,const char * file,int line)1526 ufs_get_i_offset(struct inode *ip, const char *file, int line)
1527 {
1528 ufs_assert_inode_offset_owner(ip, &ip->i_offset_tracker, "i_offset",
1529 file, line);
1530 return (ip->i_offset);
1531 }
1532
1533 void
ufs_set_i_offset(struct inode * ip,doff_t off,const char * file,int line)1534 ufs_set_i_offset(struct inode *ip, doff_t off, const char *file, int line)
1535 {
1536 ufs_set_inode_offset_owner(ip, &ip->i_offset_tracker, file, line);
1537 ip->i_offset = off;
1538 }
1539
1540 int32_t
ufs_get_i_count(struct inode * ip,const char * file,int line)1541 ufs_get_i_count(struct inode *ip, const char *file, int line)
1542 {
1543 ufs_assert_inode_offset_owner(ip, &ip->i_count_tracker, "i_count",
1544 file, line);
1545 return (ip->i_count);
1546 }
1547
1548 void
ufs_set_i_count(struct inode * ip,int32_t cnt,const char * file,int line)1549 ufs_set_i_count(struct inode *ip, int32_t cnt, const char *file, int line)
1550 {
1551 ufs_set_inode_offset_owner(ip, &ip->i_count_tracker, file, line);
1552 ip->i_count = cnt;
1553 }
1554
1555 doff_t
ufs_get_i_endoff(struct inode * ip,const char * file,int line)1556 ufs_get_i_endoff(struct inode *ip, const char *file, int line)
1557 {
1558 ufs_assert_inode_offset_owner(ip, &ip->i_endoff_tracker, "i_endoff",
1559 file, line);
1560 return (ip->i_endoff);
1561 }
1562
1563 void
ufs_set_i_endoff(struct inode * ip,doff_t off,const char * file,int line)1564 ufs_set_i_endoff(struct inode *ip, doff_t off, const char *file, int line)
1565 {
1566 ufs_set_inode_offset_owner(ip, &ip->i_endoff_tracker, file, line);
1567 ip->i_endoff = off;
1568 }
1569
1570 #endif
1571