1 // SPDX-License-Identifier: LGPL-2.1
2 /*
3 *
4 * vfs operations that deal with dentries
5 *
6 * Copyright (C) International Business Machines Corp., 2002,2009
7 * Author(s): Steve French (sfrench@us.ibm.com)
8 *
9 */
10 #include <linux/fs.h>
11 #include <linux/stat.h>
12 #include <linux/slab.h>
13 #include <linux/namei.h>
14 #include <linux/mount.h>
15 #include <linux/file.h>
16 #include "cifsfs.h"
17 #include "cifspdu.h"
18 #include "cifsglob.h"
19 #include "cifsproto.h"
20 #include "cifs_debug.h"
21 #include "cifs_fs_sb.h"
22 #include "cifs_unicode.h"
23 #include "fs_context.h"
24 #include "cifs_ioctl.h"
25 #include "fscache.h"
26
27 static void
28 renew_parental_timestamps(struct dentry *direntry)
29 {
30 /* BB check if there is a way to get the kernel to do this or if we
31 really need this */
32 do {
33 cifs_set_time(direntry, jiffies);
34 direntry = direntry->d_parent;
35 } while (!IS_ROOT(direntry));
36 }
37
38 char *
39 cifs_build_path_to_root(struct smb3_fs_context *ctx, struct cifs_sb_info *cifs_sb,
40 struct cifs_tcon *tcon, int add_treename)
41 {
42 int pplen = ctx->prepath ? strlen(ctx->prepath) + 1 : 0;
43 int dfsplen;
44 char *full_path = NULL;
45
46 /* if no prefix path, simply set path to the root of share to "" */
47 if (pplen == 0) {
48 full_path = kzalloc(1, GFP_KERNEL);
49 return full_path;
50 }
51
52 if (add_treename)
53 dfsplen = strnlen(tcon->tree_name, MAX_TREE_SIZE + 1);
54 else
55 dfsplen = 0;
56
57 full_path = kmalloc(dfsplen + pplen + 1, GFP_KERNEL);
58 if (full_path == NULL)
59 return full_path;
60
61 if (dfsplen)
62 memcpy(full_path, tcon->tree_name, dfsplen);
63 full_path[dfsplen] = CIFS_DIR_SEP(cifs_sb);
64 memcpy(full_path + dfsplen + 1, ctx->prepath, pplen);
65 convert_delimiter(full_path, CIFS_DIR_SEP(cifs_sb));
66 return full_path;
67 }
68
69 /* Note: caller must free return buffer */
70 const char *
71 build_path_from_dentry(struct dentry *direntry, void *page)
72 {
73 struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
74 struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
75 bool prefix = tcon->Flags & SMB_SHARE_IS_IN_DFS;
76
77 return build_path_from_dentry_optional_prefix(direntry, page,
78 prefix);
79 }
80
81 char *__build_path_from_dentry_optional_prefix(struct dentry *direntry, void *page,
82 const char *tree, int tree_len,
83 bool prefix)
84 {
85 int dfsplen;
86 int pplen = 0;
87 struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
88 char dirsep = CIFS_DIR_SEP(cifs_sb);
89 char *s;
90
91 if (unlikely(!page))
92 return ERR_PTR(-ENOMEM);
93
94 if (prefix)
95 dfsplen = strnlen(tree, tree_len + 1);
96 else
97 dfsplen = 0;
98
99 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH)
100 pplen = cifs_sb->prepath ? strlen(cifs_sb->prepath) + 1 : 0;
101
102 s = dentry_path_raw(direntry, page, PATH_MAX);
103 if (IS_ERR(s))
104 return s;
105 if (!s[1]) // for root we want "", not "/"
106 s++;
107 if (s < (char *)page + pplen + dfsplen)
108 return ERR_PTR(-ENAMETOOLONG);
109 if (pplen) {
110 cifs_dbg(FYI, "using cifs_sb prepath <%s>\n", cifs_sb->prepath);
111 s -= pplen;
112 memcpy(s + 1, cifs_sb->prepath, pplen - 1);
113 *s = '/';
114 }
115 if (dirsep != '/') {
116 /* BB test paths to Windows with '/' in the midst of prepath */
117 char *p;
118
119 for (p = s; *p; p++)
120 if (*p == '/')
121 *p = dirsep;
122 }
123 if (dfsplen) {
124 s -= dfsplen;
125 memcpy(s, tree, dfsplen);
126 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS) {
127 int i;
128 for (i = 0; i < dfsplen; i++) {
129 if (s[i] == '\\')
130 s[i] = '/';
131 }
132 }
133 }
134 return s;
135 }
136
137 char *build_path_from_dentry_optional_prefix(struct dentry *direntry, void *page,
138 bool prefix)
139 {
140 struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
141 struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
142
143 return __build_path_from_dentry_optional_prefix(direntry, page, tcon->tree_name,
144 MAX_TREE_SIZE, prefix);
145 }
146
147 /*
148 * Don't allow path components longer than the server max.
149 * Don't allow the separator character in a path component.
150 * The VFS will not allow "/", but "\" is allowed by posix.
151 */
152 static int
153 check_name(struct dentry *direntry, struct cifs_tcon *tcon)
154 {
155 struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
156 int i;
157
158 if (unlikely(tcon->fsAttrInfo.MaxPathNameComponentLength &&
159 direntry->d_name.len >
160 le32_to_cpu(tcon->fsAttrInfo.MaxPathNameComponentLength)))
161 return -ENAMETOOLONG;
162
163 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS)) {
164 for (i = 0; i < direntry->d_name.len; i++) {
165 if (direntry->d_name.name[i] == '\\') {
166 cifs_dbg(FYI, "Invalid file name\n");
167 return -EINVAL;
168 }
169 }
170 }
171 return 0;
172 }
173
174
175 /* Inode operations in similar order to how they appear in Linux file fs.h */
176
177 static int cifs_do_create(struct inode *inode, struct dentry *direntry, unsigned int xid,
178 struct tcon_link *tlink, unsigned int oflags, umode_t mode, __u32 *oplock,
179 struct cifs_fid *fid, struct cifs_open_info_data *buf)
180 {
181 int rc = -ENOENT;
182 int create_options = CREATE_NOT_DIR;
183 int desired_access;
184 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
185 struct cifs_tcon *tcon = tlink_tcon(tlink);
186 const char *full_path;
187 void *page = alloc_dentry_path();
188 struct inode *newinode = NULL;
189 int disposition;
190 struct TCP_Server_Info *server = tcon->ses->server;
191 struct cifs_open_parms oparms;
192 int rdwr_for_fscache = 0;
193
194 *oplock = 0;
195 if (tcon->ses->server->oplocks)
196 *oplock = REQ_OPLOCK;
197
198 full_path = build_path_from_dentry(direntry, page);
199 if (IS_ERR(full_path)) {
200 free_dentry_path(page);
201 return PTR_ERR(full_path);
202 }
203
204 /* If we're caching, we need to be able to fill in around partial writes. */
205 if (cifs_fscache_enabled(inode) && (oflags & O_ACCMODE) == O_WRONLY)
206 rdwr_for_fscache = 1;
207
208 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
209 if (tcon->unix_ext && cap_unix(tcon->ses) && !tcon->broken_posix_open &&
210 (CIFS_UNIX_POSIX_PATH_OPS_CAP &
211 le64_to_cpu(tcon->fsUnixInfo.Capability))) {
212 rc = cifs_posix_open(full_path, &newinode, inode->i_sb, mode,
213 oflags, oplock, &fid->netfid, xid);
214 switch (rc) {
215 case 0:
216 if (newinode == NULL) {
217 /* query inode info */
218 goto cifs_create_get_file_info;
219 }
220
221 if (S_ISDIR(newinode->i_mode)) {
222 CIFSSMBClose(xid, tcon, fid->netfid);
223 iput(newinode);
224 rc = -EISDIR;
225 goto out;
226 }
227
228 if (!S_ISREG(newinode->i_mode)) {
229 /*
230 * The server may allow us to open things like
231 * FIFOs, but the client isn't set up to deal
232 * with that. If it's not a regular file, just
233 * close it and proceed as if it were a normal
234 * lookup.
235 */
236 CIFSSMBClose(xid, tcon, fid->netfid);
237 goto cifs_create_get_file_info;
238 }
239 /* success, no need to query */
240 goto cifs_create_set_dentry;
241
242 case -ENOENT:
243 goto cifs_create_get_file_info;
244
245 case -EIO:
246 case -EINVAL:
247 /*
248 * EIO could indicate that (posix open) operation is not
249 * supported, despite what server claimed in capability
250 * negotiation.
251 *
252 * POSIX open in samba versions 3.3.1 and earlier could
253 * incorrectly fail with invalid parameter.
254 */
255 tcon->broken_posix_open = true;
256 break;
257
258 case -EREMOTE:
259 case -EOPNOTSUPP:
260 /*
261 * EREMOTE indicates DFS junction, which is not handled
262 * in posix open. If either that or op not supported
263 * returned, follow the normal lookup.
264 */
265 break;
266
267 default:
268 goto out;
269 }
270 /*
271 * fallthrough to retry, using older open call, this is case
272 * where server does not support this SMB level, and falsely
273 * claims capability (also get here for DFS case which should be
274 * rare for path not covered on files)
275 */
276 }
277 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
278
279 desired_access = 0;
280 if (OPEN_FMODE(oflags) & FMODE_READ)
281 desired_access |= GENERIC_READ; /* is this too little? */
282 if (OPEN_FMODE(oflags) & FMODE_WRITE)
283 desired_access |= GENERIC_WRITE;
284 if (rdwr_for_fscache == 1)
285 desired_access |= GENERIC_READ;
286
287 disposition = FILE_OVERWRITE_IF;
288 if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
289 disposition = FILE_CREATE;
290 else if ((oflags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))
291 disposition = FILE_OVERWRITE_IF;
292 else if ((oflags & O_CREAT) == O_CREAT)
293 disposition = FILE_OPEN_IF;
294 else
295 cifs_dbg(FYI, "Create flag not set in create function\n");
296
297 /*
298 * BB add processing to set equivalent of mode - e.g. via CreateX with
299 * ACLs
300 */
301
302 if (!server->ops->open) {
303 rc = -ENOSYS;
304 goto out;
305 }
306
307 /*
308 * if we're not using unix extensions, see if we need to set
309 * ATTR_READONLY on the create call
310 */
311 if (!tcon->unix_ext && (mode & S_IWUGO) == 0)
312 create_options |= CREATE_OPTION_READONLY;
313
314 retry_open:
315 oparms = (struct cifs_open_parms) {
316 .tcon = tcon,
317 .cifs_sb = cifs_sb,
318 .desired_access = desired_access,
319 .create_options = cifs_create_options(cifs_sb, create_options),
320 .disposition = disposition,
321 .path = full_path,
322 .fid = fid,
323 .mode = mode,
324 };
325 rc = server->ops->open(xid, &oparms, oplock, buf);
326 if (rc) {
327 cifs_dbg(FYI, "cifs_create returned 0x%x\n", rc);
328 if (rc == -EACCES && rdwr_for_fscache == 1) {
329 desired_access &= ~GENERIC_READ;
330 rdwr_for_fscache = 2;
331 goto retry_open;
332 }
333 goto out;
334 }
335 if (rdwr_for_fscache == 2)
336 cifs_invalidate_cache(inode, FSCACHE_INVAL_DIO_WRITE);
337
338 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
339 /*
340 * If Open reported that we actually created a file then we now have to
341 * set the mode if possible.
342 */
343 if ((tcon->unix_ext) && (*oplock & CIFS_CREATE_ACTION)) {
344 struct cifs_unix_set_info_args args = {
345 .mode = mode,
346 .ctime = NO_CHANGE_64,
347 .atime = NO_CHANGE_64,
348 .mtime = NO_CHANGE_64,
349 .device = 0,
350 };
351
352 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
353 args.uid = current_fsuid();
354 if (inode->i_mode & S_ISGID)
355 args.gid = inode->i_gid;
356 else
357 args.gid = current_fsgid();
358 } else {
359 args.uid = INVALID_UID; /* no change */
360 args.gid = INVALID_GID; /* no change */
361 }
362 CIFSSMBUnixSetFileInfo(xid, tcon, &args, fid->netfid,
363 current->tgid);
364 } else {
365 /*
366 * BB implement mode setting via Windows security
367 * descriptors e.g.
368 */
369 /* CIFSSMBWinSetPerms(xid,tcon,path,mode,-1,-1,nls);*/
370
371 /* Could set r/o dos attribute if mode & 0222 == 0 */
372 }
373
374 cifs_create_get_file_info:
375 /* server might mask mode so we have to query for it */
376 if (tcon->unix_ext)
377 rc = cifs_get_inode_info_unix(&newinode, full_path, inode->i_sb,
378 xid);
379 else {
380 #else
381 {
382 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
383 /* TODO: Add support for calling POSIX query info here, but passing in fid */
384 rc = cifs_get_inode_info(&newinode, full_path, buf, inode->i_sb, xid, fid);
385 if (newinode) {
386 if (server->ops->set_lease_key)
387 server->ops->set_lease_key(newinode, fid);
388 if ((*oplock & CIFS_CREATE_ACTION) && S_ISREG(newinode->i_mode)) {
389 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DYNPERM)
390 newinode->i_mode = mode;
391 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
392 newinode->i_uid = current_fsuid();
393 if (inode->i_mode & S_ISGID)
394 newinode->i_gid = inode->i_gid;
395 else
396 newinode->i_gid = current_fsgid();
397 }
398 }
399 }
400 }
401
402 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
403 cifs_create_set_dentry:
404 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
405 if (rc != 0) {
406 cifs_dbg(FYI, "Create worked, get_inode_info failed rc = %d\n",
407 rc);
408 goto out_err;
409 }
410
411 if (newinode)
412 if (S_ISDIR(newinode->i_mode)) {
413 rc = -EISDIR;
414 goto out_err;
415 }
416
417 d_drop(direntry);
418 d_add(direntry, newinode);
419
420 out:
421 free_dentry_path(page);
422 return rc;
423
424 out_err:
425 if (server->ops->close)
426 server->ops->close(xid, tcon, fid);
427 if (newinode)
428 iput(newinode);
429 goto out;
430 }
431
432 int
433 cifs_atomic_open(struct inode *inode, struct dentry *direntry,
434 struct file *file, unsigned oflags, umode_t mode)
435 {
436 int rc;
437 unsigned int xid;
438 struct tcon_link *tlink;
439 struct cifs_tcon *tcon;
440 struct TCP_Server_Info *server;
441 struct cifs_fid fid = {};
442 struct cifs_pending_open open;
443 __u32 oplock;
444 struct cifsFileInfo *file_info;
445 struct cifs_open_info_data buf = {};
446
447 if (unlikely(cifs_forced_shutdown(CIFS_SB(inode->i_sb))))
448 return -EIO;
449
450 /*
451 * Posix open is only called (at lookup time) for file create now. For
452 * opens (rather than creates), because we do not know if it is a file
453 * or directory yet, and current Samba no longer allows us to do posix
454 * open on dirs, we could end up wasting an open call on what turns out
455 * to be a dir. For file opens, we wait to call posix open till
456 * cifs_open. It could be added to atomic_open in the future but the
457 * performance tradeoff of the extra network request when EISDIR or
458 * EACCES is returned would have to be weighed against the 50% reduction
459 * in network traffic in the other paths.
460 */
461 if (!(oflags & O_CREAT)) {
462 struct dentry *res;
463
464 /*
465 * Check for hashed negative dentry. We have already revalidated
466 * the dentry and it is fine. No need to perform another lookup.
467 */
468 if (!d_in_lookup(direntry))
469 return -ENOENT;
470
471 res = cifs_lookup(inode, direntry, 0);
472 if (IS_ERR(res))
473 return PTR_ERR(res);
474
475 return finish_no_open(file, res);
476 }
477
478 xid = get_xid();
479
480 cifs_dbg(FYI, "parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
481 inode, direntry, direntry);
482
483 tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));
484 if (IS_ERR(tlink)) {
485 rc = PTR_ERR(tlink);
486 goto out_free_xid;
487 }
488
489 tcon = tlink_tcon(tlink);
490
491 rc = check_name(direntry, tcon);
492 if (rc)
493 goto out;
494
495 server = tcon->ses->server;
496
497 if (server->ops->new_lease_key)
498 server->ops->new_lease_key(&fid);
499
500 cifs_add_pending_open(&fid, tlink, &open);
501
502 rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode,
503 &oplock, &fid, &buf);
504 if (rc) {
505 cifs_del_pending_open(&open);
506 goto out;
507 }
508
509 if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
510 file->f_mode |= FMODE_CREATED;
511
512 rc = finish_open(file, direntry, generic_file_open);
513 if (rc) {
514 if (server->ops->close)
515 server->ops->close(xid, tcon, &fid);
516 cifs_del_pending_open(&open);
517 goto out;
518 }
519
520 if (file->f_flags & O_DIRECT &&
521 CIFS_SB(inode->i_sb)->mnt_cifs_flags & CIFS_MOUNT_STRICT_IO) {
522 if (CIFS_SB(inode->i_sb)->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
523 file->f_op = &cifs_file_direct_nobrl_ops;
524 else
525 file->f_op = &cifs_file_direct_ops;
526 }
527
528 file_info = cifs_new_fileinfo(&fid, file, tlink, oplock, buf.symlink_target);
529 if (file_info == NULL) {
530 if (server->ops->close)
531 server->ops->close(xid, tcon, &fid);
532 cifs_del_pending_open(&open);
533 rc = -ENOMEM;
534 goto out;
535 }
536
537 fscache_use_cookie(cifs_inode_cookie(file_inode(file)),
538 file->f_mode & FMODE_WRITE);
539
540 out:
541 cifs_put_tlink(tlink);
542 out_free_xid:
543 free_xid(xid);
544 cifs_free_open_info(&buf);
545 return rc;
546 }
547
548 int cifs_create(struct mnt_idmap *idmap, struct inode *inode,
549 struct dentry *direntry, umode_t mode, bool excl)
550 {
551 int rc;
552 unsigned int xid = get_xid();
553 /*
554 * BB below access is probably too much for mknod to request
555 * but we have to do query and setpathinfo so requesting
556 * less could fail (unless we want to request getatr and setatr
557 * permissions (only). At least for POSIX we do not have to
558 * request so much.
559 */
560 unsigned oflags = O_EXCL | O_CREAT | O_RDWR;
561 struct tcon_link *tlink;
562 struct cifs_tcon *tcon;
563 struct TCP_Server_Info *server;
564 struct cifs_fid fid;
565 __u32 oplock;
566 struct cifs_open_info_data buf = {};
567
568 cifs_dbg(FYI, "cifs_create parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
569 inode, direntry, direntry);
570
571 if (unlikely(cifs_forced_shutdown(CIFS_SB(inode->i_sb)))) {
572 rc = -EIO;
573 goto out_free_xid;
574 }
575
576 tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));
577 rc = PTR_ERR(tlink);
578 if (IS_ERR(tlink))
579 goto out_free_xid;
580
581 tcon = tlink_tcon(tlink);
582 server = tcon->ses->server;
583
584 if (server->ops->new_lease_key)
585 server->ops->new_lease_key(&fid);
586
587 rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode, &oplock, &fid, &buf);
588 if (!rc && server->ops->close)
589 server->ops->close(xid, tcon, &fid);
590
591 cifs_free_open_info(&buf);
592 cifs_put_tlink(tlink);
593 out_free_xid:
594 free_xid(xid);
595 return rc;
596 }
597
598 int cifs_mknod(struct mnt_idmap *idmap, struct inode *inode,
599 struct dentry *direntry, umode_t mode, dev_t device_number)
600 {
601 int rc = -EPERM;
602 unsigned int xid;
603 struct cifs_sb_info *cifs_sb;
604 struct tcon_link *tlink;
605 struct cifs_tcon *tcon;
606 const char *full_path;
607 void *page;
608
609 if (!old_valid_dev(device_number))
610 return -EINVAL;
611
612 cifs_sb = CIFS_SB(inode->i_sb);
613 if (unlikely(cifs_forced_shutdown(cifs_sb)))
614 return -EIO;
615
616 tlink = cifs_sb_tlink(cifs_sb);
617 if (IS_ERR(tlink))
618 return PTR_ERR(tlink);
619
620 page = alloc_dentry_path();
621 tcon = tlink_tcon(tlink);
622 xid = get_xid();
623
624 full_path = build_path_from_dentry(direntry, page);
625 if (IS_ERR(full_path)) {
626 rc = PTR_ERR(full_path);
627 goto mknod_out;
628 }
629
630 trace_smb3_mknod_enter(xid, tcon->ses->Suid, tcon->tid, full_path);
631
632 rc = tcon->ses->server->ops->make_node(xid, inode, direntry, tcon,
633 full_path, mode,
634 device_number);
635
636 mknod_out:
637 if (rc)
638 trace_smb3_mknod_err(xid, tcon->ses->Suid, tcon->tid, rc);
639 else
640 trace_smb3_mknod_done(xid, tcon->ses->Suid, tcon->tid);
641
642 free_dentry_path(page);
643 free_xid(xid);
644 cifs_put_tlink(tlink);
645 return rc;
646 }
647
648 struct dentry *
649 cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,
650 unsigned int flags)
651 {
652 unsigned int xid;
653 int rc = 0; /* to get around spurious gcc warning, set to zero here */
654 struct cifs_sb_info *cifs_sb;
655 struct tcon_link *tlink;
656 struct cifs_tcon *pTcon;
657 struct inode *newInode = NULL;
658 const char *full_path;
659 void *page;
660 int retry_count = 0;
661
662 xid = get_xid();
663
664 cifs_dbg(FYI, "parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
665 parent_dir_inode, direntry, direntry);
666
667 /* check whether path exists */
668
669 cifs_sb = CIFS_SB(parent_dir_inode->i_sb);
670 tlink = cifs_sb_tlink(cifs_sb);
671 if (IS_ERR(tlink)) {
672 free_xid(xid);
673 return ERR_CAST(tlink);
674 }
675 pTcon = tlink_tcon(tlink);
676
677 rc = check_name(direntry, pTcon);
678 if (unlikely(rc)) {
679 cifs_put_tlink(tlink);
680 free_xid(xid);
681 return ERR_PTR(rc);
682 }
683
684 /* can not grab the rename sem here since it would
685 deadlock in the cases (beginning of sys_rename itself)
686 in which we already have the sb rename sem */
687 page = alloc_dentry_path();
688 full_path = build_path_from_dentry(direntry, page);
689 if (IS_ERR(full_path)) {
690 cifs_put_tlink(tlink);
691 free_xid(xid);
692 free_dentry_path(page);
693 return ERR_CAST(full_path);
694 }
695
696 if (d_really_is_positive(direntry)) {
697 cifs_dbg(FYI, "non-NULL inode in lookup\n");
698 } else {
699 cifs_dbg(FYI, "NULL inode in lookup\n");
700 }
701 cifs_dbg(FYI, "Full path: %s inode = 0x%p\n",
702 full_path, d_inode(direntry));
703
704 again:
705 if (pTcon->posix_extensions) {
706 rc = smb311_posix_get_inode_info(&newInode, full_path, NULL,
707 parent_dir_inode->i_sb, xid);
708 } else if (pTcon->unix_ext) {
709 rc = cifs_get_inode_info_unix(&newInode, full_path,
710 parent_dir_inode->i_sb, xid);
711 } else {
712 rc = cifs_get_inode_info(&newInode, full_path, NULL,
713 parent_dir_inode->i_sb, xid, NULL);
714 }
715
716 if (rc == 0) {
717 /* since paths are not looked up by component - the parent
718 directories are presumed to be good here */
719 renew_parental_timestamps(direntry);
720 } else if (rc == -EAGAIN && retry_count++ < 10) {
721 goto again;
722 } else if (rc == -ENOENT) {
723 cifs_set_time(direntry, jiffies);
724 newInode = NULL;
725 } else {
726 if (rc != -EACCES) {
727 cifs_dbg(FYI, "Unexpected lookup error %d\n", rc);
728 /* We special case check for Access Denied - since that
729 is a common return code */
730 }
731 newInode = ERR_PTR(rc);
732 }
733 free_dentry_path(page);
734 cifs_put_tlink(tlink);
735 free_xid(xid);
736 return d_splice_alias(newInode, direntry);
737 }
738
739 static int
740 cifs_d_revalidate(struct dentry *direntry, unsigned int flags)
741 {
742 struct inode *inode;
743 int rc;
744
745 if (flags & LOOKUP_RCU)
746 return -ECHILD;
747
748 if (d_really_is_positive(direntry)) {
749 inode = d_inode(direntry);
750 if ((flags & LOOKUP_REVAL) && !CIFS_CACHE_READ(CIFS_I(inode)))
751 CIFS_I(inode)->time = 0; /* force reval */
752
753 rc = cifs_revalidate_dentry(direntry);
754 if (rc) {
755 cifs_dbg(FYI, "cifs_revalidate_dentry failed with rc=%d", rc);
756 switch (rc) {
757 case -ENOENT:
758 case -ESTALE:
759 /*
760 * Those errors mean the dentry is invalid
761 * (file was deleted or recreated)
762 */
763 return 0;
764 default:
765 /*
766 * Otherwise some unexpected error happened
767 * report it as-is to VFS layer
768 */
769 return rc;
770 }
771 }
772 else {
773 /*
774 * If the inode wasn't known to be a dfs entry when
775 * the dentry was instantiated, such as when created
776 * via ->readdir(), it needs to be set now since the
777 * attributes will have been updated by
778 * cifs_revalidate_dentry().
779 */
780 if (IS_AUTOMOUNT(inode) &&
781 !(direntry->d_flags & DCACHE_NEED_AUTOMOUNT)) {
782 spin_lock(&direntry->d_lock);
783 direntry->d_flags |= DCACHE_NEED_AUTOMOUNT;
784 spin_unlock(&direntry->d_lock);
785 }
786
787 return 1;
788 }
789 }
790
791 /*
792 * This may be nfsd (or something), anyway, we can't see the
793 * intent of this. So, since this can be for creation, drop it.
794 */
795 if (!flags)
796 return 0;
797
798 /*
799 * Drop the negative dentry, in order to make sure to use the
800 * case sensitive name which is specified by user if this is
801 * for creation.
802 */
803 if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))
804 return 0;
805
806 if (time_after(jiffies, cifs_get_time(direntry) + HZ) || !lookupCacheEnabled)
807 return 0;
808
809 return 1;
810 }
811
812 /* static int cifs_d_delete(struct dentry *direntry)
813 {
814 int rc = 0;
815
816 cifs_dbg(FYI, "In cifs d_delete, name = %pd\n", direntry);
817
818 return rc;
819 } */
820
821 const struct dentry_operations cifs_dentry_ops = {
822 .d_revalidate = cifs_d_revalidate,
823 .d_automount = cifs_d_automount,
824 /* d_delete: cifs_d_delete, */ /* not needed except for debugging */
825 };
826
827 static int cifs_ci_hash(const struct dentry *dentry, struct qstr *q)
828 {
829 struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;
830 unsigned long hash;
831 wchar_t c;
832 int i, charlen;
833
834 hash = init_name_hash(dentry);
835 for (i = 0; i < q->len; i += charlen) {
836 charlen = codepage->char2uni(&q->name[i], q->len - i, &c);
837 /* error out if we can't convert the character */
838 if (unlikely(charlen < 0))
839 return charlen;
840 hash = partial_name_hash(cifs_toupper(c), hash);
841 }
842 q->hash = end_name_hash(hash);
843
844 return 0;
845 }
846
847 static int cifs_ci_compare(const struct dentry *dentry,
848 unsigned int len, const char *str, const struct qstr *name)
849 {
850 struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;
851 wchar_t c1, c2;
852 int i, l1, l2;
853
854 /*
855 * We make the assumption here that uppercase characters in the local
856 * codepage are always the same length as their lowercase counterparts.
857 *
858 * If that's ever not the case, then this will fail to match it.
859 */
860 if (name->len != len)
861 return 1;
862
863 for (i = 0; i < len; i += l1) {
864 /* Convert characters in both strings to UTF-16. */
865 l1 = codepage->char2uni(&str[i], len - i, &c1);
866 l2 = codepage->char2uni(&name->name[i], name->len - i, &c2);
867
868 /*
869 * If we can't convert either character, just declare it to
870 * be 1 byte long and compare the original byte.
871 */
872 if (unlikely(l1 < 0 && l2 < 0)) {
873 if (str[i] != name->name[i])
874 return 1;
875 l1 = 1;
876 continue;
877 }
878
879 /*
880 * Here, we again ass|u|me that upper/lowercase versions of
881 * a character are the same length in the local NLS.
882 */
883 if (l1 != l2)
884 return 1;
885
886 /* Now compare uppercase versions of these characters */
887 if (cifs_toupper(c1) != cifs_toupper(c2))
888 return 1;
889 }
890
891 return 0;
892 }
893
894 const struct dentry_operations cifs_ci_dentry_ops = {
895 .d_revalidate = cifs_d_revalidate,
896 .d_hash = cifs_ci_hash,
897 .d_compare = cifs_ci_compare,
898 .d_automount = cifs_d_automount,
899 };
900
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