1 // SPDX-License-Identifier: LGPL-2.1
4 * vfs operations that deal with dentries
6 * Copyright (C) International Business Machines Corp., 2002,2009
7 * Author(s): Steve French (sfrench@us.ibm.com)
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>
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"
28 renew_parental_timestamps(struct dentry *direntry)
30 /* BB check if there is a way to get the kernel to do this or if we
33 cifs_set_time(direntry, jiffies);
34 direntry = direntry->d_parent;
35 } while (!IS_ROOT(direntry));
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)
42 int pplen = ctx->prepath ? strlen(ctx->prepath) + 1 : 0;
44 char *full_path = NULL;
46 /* if no prefix path, simply set path to the root of share to "" */
48 full_path = kzalloc(1, GFP_KERNEL);
53 dfsplen = strnlen(tcon->tree_name, MAX_TREE_SIZE + 1);
57 full_path = kmalloc(dfsplen + pplen + 1, GFP_KERNEL);
58 if (full_path == NULL)
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));
69 /* Note: caller must free return buffer */
71 build_path_from_dentry(struct dentry *direntry, void *page)
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;
77 return build_path_from_dentry_optional_prefix(direntry, page,
82 build_path_from_dentry_optional_prefix(struct dentry *direntry, void *page,
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);
93 return ERR_PTR(-ENOMEM);
96 dfsplen = strnlen(tcon->tree_name, MAX_TREE_SIZE + 1);
100 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH)
101 pplen = cifs_sb->prepath ? strlen(cifs_sb->prepath) + 1 : 0;
103 s = dentry_path_raw(direntry, page, PATH_MAX);
106 if (!s[1]) // for root we want "", not "/"
108 if (s < (char *)page + pplen + dfsplen)
109 return ERR_PTR(-ENAMETOOLONG);
111 cifs_dbg(FYI, "using cifs_sb prepath <%s>\n", cifs_sb->prepath);
113 memcpy(s + 1, cifs_sb->prepath, pplen - 1);
117 /* BB test paths to Windows with '/' in the midst of prepath */
126 memcpy(s, tcon->tree_name, dfsplen);
127 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS) {
129 for (i = 0; i < dfsplen; i++) {
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.
144 check_name(struct dentry *direntry, struct cifs_tcon *tcon)
146 struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
149 if (unlikely(tcon->fsAttrInfo.MaxPathNameComponentLength &&
150 direntry->d_name.len >
151 le32_to_cpu(tcon->fsAttrInfo.MaxPathNameComponentLength)))
152 return -ENAMETOOLONG;
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");
166 /* Inode operations in similar order to how they appear in Linux file fs.h */
168 static int cifs_do_create(struct inode *inode, struct dentry *direntry, unsigned int xid,
169 struct tcon_link *tlink, unsigned int oflags, umode_t mode, __u32 *oplock,
170 struct cifs_fid *fid, struct cifs_open_info_data *buf)
173 int create_options = CREATE_NOT_DIR;
175 struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
176 struct cifs_tcon *tcon = tlink_tcon(tlink);
177 const char *full_path;
178 void *page = alloc_dentry_path();
179 struct inode *newinode = NULL;
181 struct TCP_Server_Info *server = tcon->ses->server;
182 struct cifs_open_parms oparms;
183 int rdwr_for_fscache = 0;
186 if (tcon->ses->server->oplocks)
187 *oplock = REQ_OPLOCK;
189 full_path = build_path_from_dentry(direntry, page);
190 if (IS_ERR(full_path)) {
191 free_dentry_path(page);
192 return PTR_ERR(full_path);
195 /* If we're caching, we need to be able to fill in around partial writes. */
196 if (cifs_fscache_enabled(inode) && (oflags & O_ACCMODE) == O_WRONLY)
197 rdwr_for_fscache = 1;
199 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
200 if (tcon->unix_ext && cap_unix(tcon->ses) && !tcon->broken_posix_open &&
201 (CIFS_UNIX_POSIX_PATH_OPS_CAP &
202 le64_to_cpu(tcon->fsUnixInfo.Capability))) {
203 rc = cifs_posix_open(full_path, &newinode, inode->i_sb, mode,
204 oflags, oplock, &fid->netfid, xid);
207 if (newinode == NULL) {
208 /* query inode info */
209 goto cifs_create_get_file_info;
212 if (S_ISDIR(newinode->i_mode)) {
213 CIFSSMBClose(xid, tcon, fid->netfid);
219 if (!S_ISREG(newinode->i_mode)) {
221 * The server may allow us to open things like
222 * FIFOs, but the client isn't set up to deal
223 * with that. If it's not a regular file, just
224 * close it and proceed as if it were a normal
227 CIFSSMBClose(xid, tcon, fid->netfid);
228 goto cifs_create_get_file_info;
230 /* success, no need to query */
231 goto cifs_create_set_dentry;
234 goto cifs_create_get_file_info;
239 * EIO could indicate that (posix open) operation is not
240 * supported, despite what server claimed in capability
243 * POSIX open in samba versions 3.3.1 and earlier could
244 * incorrectly fail with invalid parameter.
246 tcon->broken_posix_open = true;
252 * EREMOTE indicates DFS junction, which is not handled
253 * in posix open. If either that or op not supported
254 * returned, follow the normal lookup.
262 * fallthrough to retry, using older open call, this is case
263 * where server does not support this SMB level, and falsely
264 * claims capability (also get here for DFS case which should be
265 * rare for path not covered on files)
268 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
271 if (OPEN_FMODE(oflags) & FMODE_READ)
272 desired_access |= GENERIC_READ; /* is this too little? */
273 if (OPEN_FMODE(oflags) & FMODE_WRITE)
274 desired_access |= GENERIC_WRITE;
275 if (rdwr_for_fscache == 1)
276 desired_access |= GENERIC_READ;
278 disposition = FILE_OVERWRITE_IF;
279 if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
280 disposition = FILE_CREATE;
281 else if ((oflags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))
282 disposition = FILE_OVERWRITE_IF;
283 else if ((oflags & O_CREAT) == O_CREAT)
284 disposition = FILE_OPEN_IF;
286 cifs_dbg(FYI, "Create flag not set in create function\n");
289 * BB add processing to set equivalent of mode - e.g. via CreateX with
293 if (!server->ops->open) {
299 * if we're not using unix extensions, see if we need to set
300 * ATTR_READONLY on the create call
302 if (!tcon->unix_ext && (mode & S_IWUGO) == 0)
303 create_options |= CREATE_OPTION_READONLY;
306 oparms = (struct cifs_open_parms) {
309 .desired_access = desired_access,
310 .create_options = cifs_create_options(cifs_sb, create_options),
311 .disposition = disposition,
316 rc = server->ops->open(xid, &oparms, oplock, buf);
318 cifs_dbg(FYI, "cifs_create returned 0x%x\n", rc);
319 if (rc == -EACCES && rdwr_for_fscache == 1) {
320 desired_access &= ~GENERIC_READ;
321 rdwr_for_fscache = 2;
326 if (rdwr_for_fscache == 2)
327 cifs_invalidate_cache(inode, FSCACHE_INVAL_DIO_WRITE);
329 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
331 * If Open reported that we actually created a file then we now have to
332 * set the mode if possible.
334 if ((tcon->unix_ext) && (*oplock & CIFS_CREATE_ACTION)) {
335 struct cifs_unix_set_info_args args = {
337 .ctime = NO_CHANGE_64,
338 .atime = NO_CHANGE_64,
339 .mtime = NO_CHANGE_64,
343 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
344 args.uid = current_fsuid();
345 if (inode->i_mode & S_ISGID)
346 args.gid = inode->i_gid;
348 args.gid = current_fsgid();
350 args.uid = INVALID_UID; /* no change */
351 args.gid = INVALID_GID; /* no change */
353 CIFSSMBUnixSetFileInfo(xid, tcon, &args, fid->netfid,
357 * BB implement mode setting via Windows security
360 /* CIFSSMBWinSetPerms(xid,tcon,path,mode,-1,-1,nls);*/
362 /* Could set r/o dos attribute if mode & 0222 == 0 */
365 cifs_create_get_file_info:
366 /* server might mask mode so we have to query for it */
368 rc = cifs_get_inode_info_unix(&newinode, full_path, inode->i_sb,
373 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
374 /* TODO: Add support for calling POSIX query info here, but passing in fid */
375 rc = cifs_get_inode_info(&newinode, full_path, buf, inode->i_sb, xid, fid);
377 if (server->ops->set_lease_key)
378 server->ops->set_lease_key(newinode, fid);
379 if ((*oplock & CIFS_CREATE_ACTION) && S_ISREG(newinode->i_mode)) {
380 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DYNPERM)
381 newinode->i_mode = mode;
382 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
383 newinode->i_uid = current_fsuid();
384 if (inode->i_mode & S_ISGID)
385 newinode->i_gid = inode->i_gid;
387 newinode->i_gid = current_fsgid();
393 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
394 cifs_create_set_dentry:
395 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
397 cifs_dbg(FYI, "Create worked, get_inode_info failed rc = %d\n",
403 if (S_ISDIR(newinode->i_mode)) {
409 d_add(direntry, newinode);
412 free_dentry_path(page);
416 if (server->ops->close)
417 server->ops->close(xid, tcon, fid);
424 cifs_atomic_open(struct inode *inode, struct dentry *direntry,
425 struct file *file, unsigned oflags, umode_t mode)
429 struct tcon_link *tlink;
430 struct cifs_tcon *tcon;
431 struct TCP_Server_Info *server;
432 struct cifs_fid fid = {};
433 struct cifs_pending_open open;
435 struct cifsFileInfo *file_info;
436 struct cifs_open_info_data buf = {};
438 if (unlikely(cifs_forced_shutdown(CIFS_SB(inode->i_sb))))
442 * Posix open is only called (at lookup time) for file create now. For
443 * opens (rather than creates), because we do not know if it is a file
444 * or directory yet, and current Samba no longer allows us to do posix
445 * open on dirs, we could end up wasting an open call on what turns out
446 * to be a dir. For file opens, we wait to call posix open till
447 * cifs_open. It could be added to atomic_open in the future but the
448 * performance tradeoff of the extra network request when EISDIR or
449 * EACCES is returned would have to be weighed against the 50% reduction
450 * in network traffic in the other paths.
452 if (!(oflags & O_CREAT)) {
456 * Check for hashed negative dentry. We have already revalidated
457 * the dentry and it is fine. No need to perform another lookup.
459 if (!d_in_lookup(direntry))
462 res = cifs_lookup(inode, direntry, 0);
466 return finish_no_open(file, res);
471 cifs_dbg(FYI, "parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
472 inode, direntry, direntry);
474 tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));
480 tcon = tlink_tcon(tlink);
482 rc = check_name(direntry, tcon);
486 server = tcon->ses->server;
488 if (server->ops->new_lease_key)
489 server->ops->new_lease_key(&fid);
491 cifs_add_pending_open(&fid, tlink, &open);
493 rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode,
494 &oplock, &fid, &buf);
496 cifs_del_pending_open(&open);
500 if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
501 file->f_mode |= FMODE_CREATED;
503 rc = finish_open(file, direntry, generic_file_open);
505 if (server->ops->close)
506 server->ops->close(xid, tcon, &fid);
507 cifs_del_pending_open(&open);
511 if (file->f_flags & O_DIRECT &&
512 CIFS_SB(inode->i_sb)->mnt_cifs_flags & CIFS_MOUNT_STRICT_IO) {
513 if (CIFS_SB(inode->i_sb)->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
514 file->f_op = &cifs_file_direct_nobrl_ops;
516 file->f_op = &cifs_file_direct_ops;
519 file_info = cifs_new_fileinfo(&fid, file, tlink, oplock, buf.symlink_target);
520 if (file_info == NULL) {
521 if (server->ops->close)
522 server->ops->close(xid, tcon, &fid);
523 cifs_del_pending_open(&open);
528 fscache_use_cookie(cifs_inode_cookie(file_inode(file)),
529 file->f_mode & FMODE_WRITE);
532 cifs_put_tlink(tlink);
535 cifs_free_open_info(&buf);
539 int cifs_create(struct user_namespace *mnt_userns, struct inode *inode,
540 struct dentry *direntry, umode_t mode, bool excl)
543 unsigned int xid = get_xid();
545 * BB below access is probably too much for mknod to request
546 * but we have to do query and setpathinfo so requesting
547 * less could fail (unless we want to request getatr and setatr
548 * permissions (only). At least for POSIX we do not have to
551 unsigned oflags = O_EXCL | O_CREAT | O_RDWR;
552 struct tcon_link *tlink;
553 struct cifs_tcon *tcon;
554 struct TCP_Server_Info *server;
557 struct cifs_open_info_data buf = {};
559 cifs_dbg(FYI, "cifs_create parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
560 inode, direntry, direntry);
562 if (unlikely(cifs_forced_shutdown(CIFS_SB(inode->i_sb)))) {
567 tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));
572 tcon = tlink_tcon(tlink);
573 server = tcon->ses->server;
575 if (server->ops->new_lease_key)
576 server->ops->new_lease_key(&fid);
578 rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode, &oplock, &fid, &buf);
579 if (!rc && server->ops->close)
580 server->ops->close(xid, tcon, &fid);
582 cifs_free_open_info(&buf);
583 cifs_put_tlink(tlink);
589 int cifs_mknod(struct user_namespace *mnt_userns, struct inode *inode,
590 struct dentry *direntry, umode_t mode, dev_t device_number)
594 struct cifs_sb_info *cifs_sb;
595 struct tcon_link *tlink;
596 struct cifs_tcon *tcon;
597 const char *full_path;
600 if (!old_valid_dev(device_number))
603 cifs_sb = CIFS_SB(inode->i_sb);
604 if (unlikely(cifs_forced_shutdown(cifs_sb)))
607 tlink = cifs_sb_tlink(cifs_sb);
609 return PTR_ERR(tlink);
611 page = alloc_dentry_path();
612 tcon = tlink_tcon(tlink);
615 full_path = build_path_from_dentry(direntry, page);
616 if (IS_ERR(full_path)) {
617 rc = PTR_ERR(full_path);
621 rc = tcon->ses->server->ops->make_node(xid, inode, direntry, tcon,
626 free_dentry_path(page);
628 cifs_put_tlink(tlink);
633 cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,
637 int rc = 0; /* to get around spurious gcc warning, set to zero here */
638 struct cifs_sb_info *cifs_sb;
639 struct tcon_link *tlink;
640 struct cifs_tcon *pTcon;
641 struct inode *newInode = NULL;
642 const char *full_path;
648 cifs_dbg(FYI, "parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
649 parent_dir_inode, direntry, direntry);
651 /* check whether path exists */
653 cifs_sb = CIFS_SB(parent_dir_inode->i_sb);
654 tlink = cifs_sb_tlink(cifs_sb);
657 return ERR_CAST(tlink);
659 pTcon = tlink_tcon(tlink);
661 rc = check_name(direntry, pTcon);
663 cifs_put_tlink(tlink);
668 /* can not grab the rename sem here since it would
669 deadlock in the cases (beginning of sys_rename itself)
670 in which we already have the sb rename sem */
671 page = alloc_dentry_path();
672 full_path = build_path_from_dentry(direntry, page);
673 if (IS_ERR(full_path)) {
674 cifs_put_tlink(tlink);
676 free_dentry_path(page);
677 return ERR_CAST(full_path);
680 if (d_really_is_positive(direntry)) {
681 cifs_dbg(FYI, "non-NULL inode in lookup\n");
683 cifs_dbg(FYI, "NULL inode in lookup\n");
685 cifs_dbg(FYI, "Full path: %s inode = 0x%p\n",
686 full_path, d_inode(direntry));
689 if (pTcon->posix_extensions)
690 rc = smb311_posix_get_inode_info(&newInode, full_path, parent_dir_inode->i_sb, xid);
691 else if (pTcon->unix_ext) {
692 rc = cifs_get_inode_info_unix(&newInode, full_path,
693 parent_dir_inode->i_sb, xid);
695 rc = cifs_get_inode_info(&newInode, full_path, NULL,
696 parent_dir_inode->i_sb, xid, NULL);
700 /* since paths are not looked up by component - the parent
701 directories are presumed to be good here */
702 renew_parental_timestamps(direntry);
703 } else if (rc == -EAGAIN && retry_count++ < 10) {
705 } else if (rc == -ENOENT) {
706 cifs_set_time(direntry, jiffies);
710 cifs_dbg(FYI, "Unexpected lookup error %d\n", rc);
711 /* We special case check for Access Denied - since that
712 is a common return code */
714 newInode = ERR_PTR(rc);
716 free_dentry_path(page);
717 cifs_put_tlink(tlink);
719 return d_splice_alias(newInode, direntry);
723 cifs_d_revalidate(struct dentry *direntry, unsigned int flags)
728 if (flags & LOOKUP_RCU)
731 if (d_really_is_positive(direntry)) {
732 inode = d_inode(direntry);
733 if ((flags & LOOKUP_REVAL) && !CIFS_CACHE_READ(CIFS_I(inode)))
734 CIFS_I(inode)->time = 0; /* force reval */
736 rc = cifs_revalidate_dentry(direntry);
738 cifs_dbg(FYI, "cifs_revalidate_dentry failed with rc=%d", rc);
743 * Those errors mean the dentry is invalid
744 * (file was deleted or recreated)
749 * Otherwise some unexpected error happened
750 * report it as-is to VFS layer
757 * If the inode wasn't known to be a dfs entry when
758 * the dentry was instantiated, such as when created
759 * via ->readdir(), it needs to be set now since the
760 * attributes will have been updated by
761 * cifs_revalidate_dentry().
763 if (IS_AUTOMOUNT(inode) &&
764 !(direntry->d_flags & DCACHE_NEED_AUTOMOUNT)) {
765 spin_lock(&direntry->d_lock);
766 direntry->d_flags |= DCACHE_NEED_AUTOMOUNT;
767 spin_unlock(&direntry->d_lock);
775 * This may be nfsd (or something), anyway, we can't see the
776 * intent of this. So, since this can be for creation, drop it.
782 * Drop the negative dentry, in order to make sure to use the
783 * case sensitive name which is specified by user if this is
786 if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))
789 if (time_after(jiffies, cifs_get_time(direntry) + HZ) || !lookupCacheEnabled)
795 /* static int cifs_d_delete(struct dentry *direntry)
799 cifs_dbg(FYI, "In cifs d_delete, name = %pd\n", direntry);
804 const struct dentry_operations cifs_dentry_ops = {
805 .d_revalidate = cifs_d_revalidate,
806 .d_automount = cifs_dfs_d_automount,
807 /* d_delete: cifs_d_delete, */ /* not needed except for debugging */
810 static int cifs_ci_hash(const struct dentry *dentry, struct qstr *q)
812 struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;
817 hash = init_name_hash(dentry);
818 for (i = 0; i < q->len; i += charlen) {
819 charlen = codepage->char2uni(&q->name[i], q->len - i, &c);
820 /* error out if we can't convert the character */
821 if (unlikely(charlen < 0))
823 hash = partial_name_hash(cifs_toupper(c), hash);
825 q->hash = end_name_hash(hash);
830 static int cifs_ci_compare(const struct dentry *dentry,
831 unsigned int len, const char *str, const struct qstr *name)
833 struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;
838 * We make the assumption here that uppercase characters in the local
839 * codepage are always the same length as their lowercase counterparts.
841 * If that's ever not the case, then this will fail to match it.
843 if (name->len != len)
846 for (i = 0; i < len; i += l1) {
847 /* Convert characters in both strings to UTF-16. */
848 l1 = codepage->char2uni(&str[i], len - i, &c1);
849 l2 = codepage->char2uni(&name->name[i], name->len - i, &c2);
852 * If we can't convert either character, just declare it to
853 * be 1 byte long and compare the original byte.
855 if (unlikely(l1 < 0 && l2 < 0)) {
856 if (str[i] != name->name[i])
863 * Here, we again ass|u|me that upper/lowercase versions of
864 * a character are the same length in the local NLS.
869 /* Now compare uppercase versions of these characters */
870 if (cifs_toupper(c1) != cifs_toupper(c2))
877 const struct dentry_operations cifs_ci_dentry_ops = {
878 .d_revalidate = cifs_d_revalidate,
879 .d_hash = cifs_ci_hash,
880 .d_compare = cifs_ci_compare,
881 .d_automount = cifs_dfs_d_automount,