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