Loading...
1/*
2 * fs/cifs/readdir.c
3 *
4 * Directory search handling
5 *
6 * Copyright (C) International Business Machines Corp., 2004, 2008
7 * Copyright (C) Red Hat, Inc., 2011
8 * Author(s): Steve French (sfrench@us.ibm.com)
9 *
10 * This library is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU Lesser General Public License as published
12 * by the Free Software Foundation; either version 2.1 of the License, or
13 * (at your option) any later version.
14 *
15 * This library is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
18 * the GNU Lesser General Public License for more details.
19 *
20 * You should have received a copy of the GNU Lesser General Public License
21 * along with this library; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 */
24#include <linux/fs.h>
25#include <linux/pagemap.h>
26#include <linux/slab.h>
27#include <linux/stat.h>
28#include "cifspdu.h"
29#include "cifsglob.h"
30#include "cifsproto.h"
31#include "cifs_unicode.h"
32#include "cifs_debug.h"
33#include "cifs_fs_sb.h"
34#include "cifsfs.h"
35
36/*
37 * To be safe - for UCS to UTF-8 with strings loaded with the rare long
38 * characters alloc more to account for such multibyte target UTF-8
39 * characters.
40 */
41#define UNICODE_NAME_MAX ((4 * NAME_MAX) + 2)
42
43#ifdef CONFIG_CIFS_DEBUG2
44static void dump_cifs_file_struct(struct file *file, char *label)
45{
46 struct cifsFileInfo *cf;
47
48 if (file) {
49 cf = file->private_data;
50 if (cf == NULL) {
51 cifs_dbg(FYI, "empty cifs private file data\n");
52 return;
53 }
54 if (cf->invalidHandle)
55 cifs_dbg(FYI, "invalid handle\n");
56 if (cf->srch_inf.endOfSearch)
57 cifs_dbg(FYI, "end of search\n");
58 if (cf->srch_inf.emptyDir)
59 cifs_dbg(FYI, "empty dir\n");
60 }
61}
62#else
63static inline void dump_cifs_file_struct(struct file *file, char *label)
64{
65}
66#endif /* DEBUG2 */
67
68/*
69 * Attempt to preload the dcache with the results from the FIND_FIRST/NEXT
70 *
71 * Find the dentry that matches "name". If there isn't one, create one. If it's
72 * a negative dentry or the uniqueid changed, then drop it and recreate it.
73 */
74static void
75cifs_prime_dcache(struct dentry *parent, struct qstr *name,
76 struct cifs_fattr *fattr)
77{
78 struct dentry *dentry, *alias;
79 struct inode *inode;
80 struct super_block *sb = parent->d_inode->i_sb;
81 struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
82
83 cifs_dbg(FYI, "%s: for %s\n", __func__, name->name);
84
85 dentry = d_hash_and_lookup(parent, name);
86 if (unlikely(IS_ERR(dentry)))
87 return;
88
89 if (dentry) {
90 int err;
91
92 inode = dentry->d_inode;
93 if (inode) {
94 /*
95 * If we're generating inode numbers, then we don't
96 * want to clobber the existing one with the one that
97 * the readdir code created.
98 */
99 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM))
100 fattr->cf_uniqueid = CIFS_I(inode)->uniqueid;
101
102 /* update inode in place if i_ino didn't change */
103 if (CIFS_I(inode)->uniqueid == fattr->cf_uniqueid) {
104 cifs_fattr_to_inode(inode, fattr);
105 goto out;
106 }
107 }
108 err = d_invalidate(dentry);
109 dput(dentry);
110 if (err)
111 return;
112 }
113
114 /*
115 * If we know that the inode will need to be revalidated immediately,
116 * then don't create a new dentry for it. We'll end up doing an on
117 * the wire call either way and this spares us an invalidation.
118 */
119 if (fattr->cf_flags & CIFS_FATTR_NEED_REVAL)
120 return;
121
122 dentry = d_alloc(parent, name);
123 if (!dentry)
124 return;
125
126 inode = cifs_iget(sb, fattr);
127 if (!inode)
128 goto out;
129
130 alias = d_materialise_unique(dentry, inode);
131 if (alias && !IS_ERR(alias))
132 dput(alias);
133out:
134 dput(dentry);
135}
136
137static void
138cifs_fill_common_info(struct cifs_fattr *fattr, struct cifs_sb_info *cifs_sb)
139{
140 fattr->cf_uid = cifs_sb->mnt_uid;
141 fattr->cf_gid = cifs_sb->mnt_gid;
142
143 if (fattr->cf_cifsattrs & ATTR_DIRECTORY) {
144 fattr->cf_mode = S_IFDIR | cifs_sb->mnt_dir_mode;
145 fattr->cf_dtype = DT_DIR;
146 } else {
147 fattr->cf_mode = S_IFREG | cifs_sb->mnt_file_mode;
148 fattr->cf_dtype = DT_REG;
149 }
150
151 /*
152 * We need to revalidate it further to make a decision about whether it
153 * is a symbolic link, DFS referral or a reparse point with a direct
154 * access like junctions, deduplicated files, NFS symlinks.
155 */
156 if (fattr->cf_cifsattrs & ATTR_REPARSE)
157 fattr->cf_flags |= CIFS_FATTR_NEED_REVAL;
158
159 /* non-unix readdir doesn't provide nlink */
160 fattr->cf_flags |= CIFS_FATTR_UNKNOWN_NLINK;
161
162 if (fattr->cf_cifsattrs & ATTR_READONLY)
163 fattr->cf_mode &= ~S_IWUGO;
164
165 /*
166 * We of course don't get ACL info in FIND_FIRST/NEXT results, so
167 * mark it for revalidation so that "ls -l" will look right. It might
168 * be super-slow, but if we don't do this then the ownership of files
169 * may look wrong since the inodes may not have timed out by the time
170 * "ls" does a stat() call on them.
171 */
172 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_ACL)
173 fattr->cf_flags |= CIFS_FATTR_NEED_REVAL;
174
175 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL &&
176 fattr->cf_cifsattrs & ATTR_SYSTEM) {
177 if (fattr->cf_eof == 0) {
178 fattr->cf_mode &= ~S_IFMT;
179 fattr->cf_mode |= S_IFIFO;
180 fattr->cf_dtype = DT_FIFO;
181 } else {
182 /*
183 * trying to get the type and mode via SFU can be slow,
184 * so just call those regular files for now, and mark
185 * for reval
186 */
187 fattr->cf_flags |= CIFS_FATTR_NEED_REVAL;
188 }
189 }
190}
191
192void
193cifs_dir_info_to_fattr(struct cifs_fattr *fattr, FILE_DIRECTORY_INFO *info,
194 struct cifs_sb_info *cifs_sb)
195{
196 memset(fattr, 0, sizeof(*fattr));
197 fattr->cf_cifsattrs = le32_to_cpu(info->ExtFileAttributes);
198 fattr->cf_eof = le64_to_cpu(info->EndOfFile);
199 fattr->cf_bytes = le64_to_cpu(info->AllocationSize);
200 fattr->cf_createtime = le64_to_cpu(info->CreationTime);
201 fattr->cf_atime = cifs_NTtimeToUnix(info->LastAccessTime);
202 fattr->cf_ctime = cifs_NTtimeToUnix(info->ChangeTime);
203 fattr->cf_mtime = cifs_NTtimeToUnix(info->LastWriteTime);
204
205 cifs_fill_common_info(fattr, cifs_sb);
206}
207
208static void
209cifs_std_info_to_fattr(struct cifs_fattr *fattr, FIND_FILE_STANDARD_INFO *info,
210 struct cifs_sb_info *cifs_sb)
211{
212 int offset = cifs_sb_master_tcon(cifs_sb)->ses->server->timeAdj;
213
214 memset(fattr, 0, sizeof(*fattr));
215 fattr->cf_atime = cnvrtDosUnixTm(info->LastAccessDate,
216 info->LastAccessTime, offset);
217 fattr->cf_ctime = cnvrtDosUnixTm(info->LastWriteDate,
218 info->LastWriteTime, offset);
219 fattr->cf_mtime = cnvrtDosUnixTm(info->LastWriteDate,
220 info->LastWriteTime, offset);
221
222 fattr->cf_cifsattrs = le16_to_cpu(info->Attributes);
223 fattr->cf_bytes = le32_to_cpu(info->AllocationSize);
224 fattr->cf_eof = le32_to_cpu(info->DataSize);
225
226 cifs_fill_common_info(fattr, cifs_sb);
227}
228
229/* BB eventually need to add the following helper function to
230 resolve NT_STATUS_STOPPED_ON_SYMLINK return code when
231 we try to do FindFirst on (NTFS) directory symlinks */
232/*
233int get_symlink_reparse_path(char *full_path, struct cifs_sb_info *cifs_sb,
234 unsigned int xid)
235{
236 __u16 fid;
237 int len;
238 int oplock = 0;
239 int rc;
240 struct cifs_tcon *ptcon = cifs_sb_tcon(cifs_sb);
241 char *tmpbuffer;
242
243 rc = CIFSSMBOpen(xid, ptcon, full_path, FILE_OPEN, GENERIC_READ,
244 OPEN_REPARSE_POINT, &fid, &oplock, NULL,
245 cifs_sb->local_nls,
246 cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
247 if (!rc) {
248 tmpbuffer = kmalloc(maxpath);
249 rc = CIFSSMBQueryReparseLinkInfo(xid, ptcon, full_path,
250 tmpbuffer,
251 maxpath -1,
252 fid,
253 cifs_sb->local_nls);
254 if (CIFSSMBClose(xid, ptcon, fid)) {
255 cifs_dbg(FYI, "Error closing temporary reparsepoint open\n");
256 }
257 }
258}
259 */
260
261static int
262initiate_cifs_search(const unsigned int xid, struct file *file)
263{
264 __u16 search_flags;
265 int rc = 0;
266 char *full_path = NULL;
267 struct cifsFileInfo *cifsFile;
268 struct cifs_sb_info *cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
269 struct tcon_link *tlink = NULL;
270 struct cifs_tcon *tcon;
271 struct TCP_Server_Info *server;
272
273 if (file->private_data == NULL) {
274 tlink = cifs_sb_tlink(cifs_sb);
275 if (IS_ERR(tlink))
276 return PTR_ERR(tlink);
277
278 cifsFile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
279 if (cifsFile == NULL) {
280 rc = -ENOMEM;
281 goto error_exit;
282 }
283 file->private_data = cifsFile;
284 cifsFile->tlink = cifs_get_tlink(tlink);
285 tcon = tlink_tcon(tlink);
286 } else {
287 cifsFile = file->private_data;
288 tcon = tlink_tcon(cifsFile->tlink);
289 }
290
291 server = tcon->ses->server;
292
293 if (!server->ops->query_dir_first) {
294 rc = -ENOSYS;
295 goto error_exit;
296 }
297
298 cifsFile->invalidHandle = true;
299 cifsFile->srch_inf.endOfSearch = false;
300
301 full_path = build_path_from_dentry(file->f_path.dentry);
302 if (full_path == NULL) {
303 rc = -ENOMEM;
304 goto error_exit;
305 }
306
307 cifs_dbg(FYI, "Full path: %s start at: %lld\n", full_path, file->f_pos);
308
309ffirst_retry:
310 /* test for Unix extensions */
311 /* but now check for them on the share/mount not on the SMB session */
312 /* if (cap_unix(tcon->ses) { */
313 if (tcon->unix_ext)
314 cifsFile->srch_inf.info_level = SMB_FIND_FILE_UNIX;
315 else if ((tcon->ses->capabilities &
316 tcon->ses->server->vals->cap_nt_find) == 0) {
317 cifsFile->srch_inf.info_level = SMB_FIND_FILE_INFO_STANDARD;
318 } else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) {
319 cifsFile->srch_inf.info_level = SMB_FIND_FILE_ID_FULL_DIR_INFO;
320 } else /* not srvinos - BB fixme add check for backlevel? */ {
321 cifsFile->srch_inf.info_level = SMB_FIND_FILE_DIRECTORY_INFO;
322 }
323
324 search_flags = CIFS_SEARCH_CLOSE_AT_END | CIFS_SEARCH_RETURN_RESUME;
325 if (backup_cred(cifs_sb))
326 search_flags |= CIFS_SEARCH_BACKUP_SEARCH;
327
328 rc = server->ops->query_dir_first(xid, tcon, full_path, cifs_sb,
329 &cifsFile->fid, search_flags,
330 &cifsFile->srch_inf);
331
332 if (rc == 0)
333 cifsFile->invalidHandle = false;
334 /* BB add following call to handle readdir on new NTFS symlink errors
335 else if STATUS_STOPPED_ON_SYMLINK
336 call get_symlink_reparse_path and retry with new path */
337 else if ((rc == -EOPNOTSUPP) &&
338 (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {
339 cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM;
340 goto ffirst_retry;
341 }
342error_exit:
343 kfree(full_path);
344 cifs_put_tlink(tlink);
345 return rc;
346}
347
348/* return length of unicode string in bytes */
349static int cifs_unicode_bytelen(const char *str)
350{
351 int len;
352 const __le16 *ustr = (const __le16 *)str;
353
354 for (len = 0; len <= PATH_MAX; len++) {
355 if (ustr[len] == 0)
356 return len << 1;
357 }
358 cifs_dbg(FYI, "Unicode string longer than PATH_MAX found\n");
359 return len << 1;
360}
361
362static char *nxt_dir_entry(char *old_entry, char *end_of_smb, int level)
363{
364 char *new_entry;
365 FILE_DIRECTORY_INFO *pDirInfo = (FILE_DIRECTORY_INFO *)old_entry;
366
367 if (level == SMB_FIND_FILE_INFO_STANDARD) {
368 FIND_FILE_STANDARD_INFO *pfData;
369 pfData = (FIND_FILE_STANDARD_INFO *)pDirInfo;
370
371 new_entry = old_entry + sizeof(FIND_FILE_STANDARD_INFO) +
372 pfData->FileNameLength;
373 } else
374 new_entry = old_entry + le32_to_cpu(pDirInfo->NextEntryOffset);
375 cifs_dbg(FYI, "new entry %p old entry %p\n", new_entry, old_entry);
376 /* validate that new_entry is not past end of SMB */
377 if (new_entry >= end_of_smb) {
378 cifs_dbg(VFS, "search entry %p began after end of SMB %p old entry %p\n",
379 new_entry, end_of_smb, old_entry);
380 return NULL;
381 } else if (((level == SMB_FIND_FILE_INFO_STANDARD) &&
382 (new_entry + sizeof(FIND_FILE_STANDARD_INFO) > end_of_smb))
383 || ((level != SMB_FIND_FILE_INFO_STANDARD) &&
384 (new_entry + sizeof(FILE_DIRECTORY_INFO) > end_of_smb))) {
385 cifs_dbg(VFS, "search entry %p extends after end of SMB %p\n",
386 new_entry, end_of_smb);
387 return NULL;
388 } else
389 return new_entry;
390
391}
392
393struct cifs_dirent {
394 const char *name;
395 size_t namelen;
396 u32 resume_key;
397 u64 ino;
398};
399
400static void cifs_fill_dirent_unix(struct cifs_dirent *de,
401 const FILE_UNIX_INFO *info, bool is_unicode)
402{
403 de->name = &info->FileName[0];
404 if (is_unicode)
405 de->namelen = cifs_unicode_bytelen(de->name);
406 else
407 de->namelen = strnlen(de->name, PATH_MAX);
408 de->resume_key = info->ResumeKey;
409 de->ino = le64_to_cpu(info->basic.UniqueId);
410}
411
412static void cifs_fill_dirent_dir(struct cifs_dirent *de,
413 const FILE_DIRECTORY_INFO *info)
414{
415 de->name = &info->FileName[0];
416 de->namelen = le32_to_cpu(info->FileNameLength);
417 de->resume_key = info->FileIndex;
418}
419
420static void cifs_fill_dirent_full(struct cifs_dirent *de,
421 const FILE_FULL_DIRECTORY_INFO *info)
422{
423 de->name = &info->FileName[0];
424 de->namelen = le32_to_cpu(info->FileNameLength);
425 de->resume_key = info->FileIndex;
426}
427
428static void cifs_fill_dirent_search(struct cifs_dirent *de,
429 const SEARCH_ID_FULL_DIR_INFO *info)
430{
431 de->name = &info->FileName[0];
432 de->namelen = le32_to_cpu(info->FileNameLength);
433 de->resume_key = info->FileIndex;
434 de->ino = le64_to_cpu(info->UniqueId);
435}
436
437static void cifs_fill_dirent_both(struct cifs_dirent *de,
438 const FILE_BOTH_DIRECTORY_INFO *info)
439{
440 de->name = &info->FileName[0];
441 de->namelen = le32_to_cpu(info->FileNameLength);
442 de->resume_key = info->FileIndex;
443}
444
445static void cifs_fill_dirent_std(struct cifs_dirent *de,
446 const FIND_FILE_STANDARD_INFO *info)
447{
448 de->name = &info->FileName[0];
449 /* one byte length, no endianess conversion */
450 de->namelen = info->FileNameLength;
451 de->resume_key = info->ResumeKey;
452}
453
454static int cifs_fill_dirent(struct cifs_dirent *de, const void *info,
455 u16 level, bool is_unicode)
456{
457 memset(de, 0, sizeof(*de));
458
459 switch (level) {
460 case SMB_FIND_FILE_UNIX:
461 cifs_fill_dirent_unix(de, info, is_unicode);
462 break;
463 case SMB_FIND_FILE_DIRECTORY_INFO:
464 cifs_fill_dirent_dir(de, info);
465 break;
466 case SMB_FIND_FILE_FULL_DIRECTORY_INFO:
467 cifs_fill_dirent_full(de, info);
468 break;
469 case SMB_FIND_FILE_ID_FULL_DIR_INFO:
470 cifs_fill_dirent_search(de, info);
471 break;
472 case SMB_FIND_FILE_BOTH_DIRECTORY_INFO:
473 cifs_fill_dirent_both(de, info);
474 break;
475 case SMB_FIND_FILE_INFO_STANDARD:
476 cifs_fill_dirent_std(de, info);
477 break;
478 default:
479 cifs_dbg(FYI, "Unknown findfirst level %d\n", level);
480 return -EINVAL;
481 }
482
483 return 0;
484}
485
486#define UNICODE_DOT cpu_to_le16(0x2e)
487
488/* return 0 if no match and 1 for . (current directory) and 2 for .. (parent) */
489static int cifs_entry_is_dot(struct cifs_dirent *de, bool is_unicode)
490{
491 int rc = 0;
492
493 if (!de->name)
494 return 0;
495
496 if (is_unicode) {
497 __le16 *ufilename = (__le16 *)de->name;
498 if (de->namelen == 2) {
499 /* check for . */
500 if (ufilename[0] == UNICODE_DOT)
501 rc = 1;
502 } else if (de->namelen == 4) {
503 /* check for .. */
504 if (ufilename[0] == UNICODE_DOT &&
505 ufilename[1] == UNICODE_DOT)
506 rc = 2;
507 }
508 } else /* ASCII */ {
509 if (de->namelen == 1) {
510 if (de->name[0] == '.')
511 rc = 1;
512 } else if (de->namelen == 2) {
513 if (de->name[0] == '.' && de->name[1] == '.')
514 rc = 2;
515 }
516 }
517
518 return rc;
519}
520
521/* Check if directory that we are searching has changed so we can decide
522 whether we can use the cached search results from the previous search */
523static int is_dir_changed(struct file *file)
524{
525 struct inode *inode = file_inode(file);
526 struct cifsInodeInfo *cifsInfo = CIFS_I(inode);
527
528 if (cifsInfo->time == 0)
529 return 1; /* directory was changed, perhaps due to unlink */
530 else
531 return 0;
532
533}
534
535static int cifs_save_resume_key(const char *current_entry,
536 struct cifsFileInfo *file_info)
537{
538 struct cifs_dirent de;
539 int rc;
540
541 rc = cifs_fill_dirent(&de, current_entry, file_info->srch_inf.info_level,
542 file_info->srch_inf.unicode);
543 if (!rc) {
544 file_info->srch_inf.presume_name = de.name;
545 file_info->srch_inf.resume_name_len = de.namelen;
546 file_info->srch_inf.resume_key = de.resume_key;
547 }
548 return rc;
549}
550
551/*
552 * Find the corresponding entry in the search. Note that the SMB server returns
553 * search entries for . and .. which complicates logic here if we choose to
554 * parse for them and we do not assume that they are located in the findfirst
555 * return buffer. We start counting in the buffer with entry 2 and increment for
556 * every entry (do not increment for . or .. entry).
557 */
558static int
559find_cifs_entry(const unsigned int xid, struct cifs_tcon *tcon, loff_t pos,
560 struct file *file, char **current_entry, int *num_to_ret)
561{
562 __u16 search_flags;
563 int rc = 0;
564 int pos_in_buf = 0;
565 loff_t first_entry_in_buffer;
566 loff_t index_to_find = pos;
567 struct cifsFileInfo *cfile = file->private_data;
568 struct cifs_sb_info *cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
569 struct TCP_Server_Info *server = tcon->ses->server;
570 /* check if index in the buffer */
571
572 if (!server->ops->query_dir_first || !server->ops->query_dir_next)
573 return -ENOSYS;
574
575 if ((cfile == NULL) || (current_entry == NULL) || (num_to_ret == NULL))
576 return -ENOENT;
577
578 *current_entry = NULL;
579 first_entry_in_buffer = cfile->srch_inf.index_of_last_entry -
580 cfile->srch_inf.entries_in_buffer;
581
582 /*
583 * If first entry in buf is zero then is first buffer
584 * in search response data which means it is likely . and ..
585 * will be in this buffer, although some servers do not return
586 * . and .. for the root of a drive and for those we need
587 * to start two entries earlier.
588 */
589
590 dump_cifs_file_struct(file, "In fce ");
591 if (((index_to_find < cfile->srch_inf.index_of_last_entry) &&
592 is_dir_changed(file)) || (index_to_find < first_entry_in_buffer)) {
593 /* close and restart search */
594 cifs_dbg(FYI, "search backing up - close and restart search\n");
595 spin_lock(&cifs_file_list_lock);
596 if (!cfile->srch_inf.endOfSearch && !cfile->invalidHandle) {
597 cfile->invalidHandle = true;
598 spin_unlock(&cifs_file_list_lock);
599 if (server->ops->close)
600 server->ops->close(xid, tcon, &cfile->fid);
601 } else
602 spin_unlock(&cifs_file_list_lock);
603 if (cfile->srch_inf.ntwrk_buf_start) {
604 cifs_dbg(FYI, "freeing SMB ff cache buf on search rewind\n");
605 if (cfile->srch_inf.smallBuf)
606 cifs_small_buf_release(cfile->srch_inf.
607 ntwrk_buf_start);
608 else
609 cifs_buf_release(cfile->srch_inf.
610 ntwrk_buf_start);
611 cfile->srch_inf.ntwrk_buf_start = NULL;
612 }
613 rc = initiate_cifs_search(xid, file);
614 if (rc) {
615 cifs_dbg(FYI, "error %d reinitiating a search on rewind\n",
616 rc);
617 return rc;
618 }
619 /* FindFirst/Next set last_entry to NULL on malformed reply */
620 if (cfile->srch_inf.last_entry)
621 cifs_save_resume_key(cfile->srch_inf.last_entry, cfile);
622 }
623
624 search_flags = CIFS_SEARCH_CLOSE_AT_END | CIFS_SEARCH_RETURN_RESUME;
625 if (backup_cred(cifs_sb))
626 search_flags |= CIFS_SEARCH_BACKUP_SEARCH;
627
628 while ((index_to_find >= cfile->srch_inf.index_of_last_entry) &&
629 (rc == 0) && !cfile->srch_inf.endOfSearch) {
630 cifs_dbg(FYI, "calling findnext2\n");
631 rc = server->ops->query_dir_next(xid, tcon, &cfile->fid,
632 search_flags,
633 &cfile->srch_inf);
634 /* FindFirst/Next set last_entry to NULL on malformed reply */
635 if (cfile->srch_inf.last_entry)
636 cifs_save_resume_key(cfile->srch_inf.last_entry, cfile);
637 if (rc)
638 return -ENOENT;
639 }
640 if (index_to_find < cfile->srch_inf.index_of_last_entry) {
641 /* we found the buffer that contains the entry */
642 /* scan and find it */
643 int i;
644 char *cur_ent;
645 char *end_of_smb = cfile->srch_inf.ntwrk_buf_start +
646 server->ops->calc_smb_size(
647 cfile->srch_inf.ntwrk_buf_start);
648
649 cur_ent = cfile->srch_inf.srch_entries_start;
650 first_entry_in_buffer = cfile->srch_inf.index_of_last_entry
651 - cfile->srch_inf.entries_in_buffer;
652 pos_in_buf = index_to_find - first_entry_in_buffer;
653 cifs_dbg(FYI, "found entry - pos_in_buf %d\n", pos_in_buf);
654
655 for (i = 0; (i < (pos_in_buf)) && (cur_ent != NULL); i++) {
656 /* go entry by entry figuring out which is first */
657 cur_ent = nxt_dir_entry(cur_ent, end_of_smb,
658 cfile->srch_inf.info_level);
659 }
660 if ((cur_ent == NULL) && (i < pos_in_buf)) {
661 /* BB fixme - check if we should flag this error */
662 cifs_dbg(VFS, "reached end of buf searching for pos in buf %d index to find %lld rc %d\n",
663 pos_in_buf, index_to_find, rc);
664 }
665 rc = 0;
666 *current_entry = cur_ent;
667 } else {
668 cifs_dbg(FYI, "index not in buffer - could not findnext into it\n");
669 return 0;
670 }
671
672 if (pos_in_buf >= cfile->srch_inf.entries_in_buffer) {
673 cifs_dbg(FYI, "can not return entries pos_in_buf beyond last\n");
674 *num_to_ret = 0;
675 } else
676 *num_to_ret = cfile->srch_inf.entries_in_buffer - pos_in_buf;
677
678 return rc;
679}
680
681static int cifs_filldir(char *find_entry, struct file *file,
682 struct dir_context *ctx,
683 char *scratch_buf, unsigned int max_len)
684{
685 struct cifsFileInfo *file_info = file->private_data;
686 struct super_block *sb = file->f_path.dentry->d_sb;
687 struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
688 struct cifs_dirent de = { NULL, };
689 struct cifs_fattr fattr;
690 struct qstr name;
691 int rc = 0;
692 ino_t ino;
693
694 rc = cifs_fill_dirent(&de, find_entry, file_info->srch_inf.info_level,
695 file_info->srch_inf.unicode);
696 if (rc)
697 return rc;
698
699 if (de.namelen > max_len) {
700 cifs_dbg(VFS, "bad search response length %zd past smb end\n",
701 de.namelen);
702 return -EINVAL;
703 }
704
705 /* skip . and .. since we added them first */
706 if (cifs_entry_is_dot(&de, file_info->srch_inf.unicode))
707 return 0;
708
709 if (file_info->srch_inf.unicode) {
710 struct nls_table *nlt = cifs_sb->local_nls;
711
712 name.name = scratch_buf;
713 name.len =
714 cifs_from_utf16((char *)name.name, (__le16 *)de.name,
715 UNICODE_NAME_MAX,
716 min_t(size_t, de.namelen,
717 (size_t)max_len), nlt,
718 cifs_sb->mnt_cifs_flags &
719 CIFS_MOUNT_MAP_SPECIAL_CHR);
720 name.len -= nls_nullsize(nlt);
721 } else {
722 name.name = de.name;
723 name.len = de.namelen;
724 }
725
726 switch (file_info->srch_inf.info_level) {
727 case SMB_FIND_FILE_UNIX:
728 cifs_unix_basic_to_fattr(&fattr,
729 &((FILE_UNIX_INFO *)find_entry)->basic,
730 cifs_sb);
731 break;
732 case SMB_FIND_FILE_INFO_STANDARD:
733 cifs_std_info_to_fattr(&fattr,
734 (FIND_FILE_STANDARD_INFO *)find_entry,
735 cifs_sb);
736 break;
737 default:
738 cifs_dir_info_to_fattr(&fattr,
739 (FILE_DIRECTORY_INFO *)find_entry,
740 cifs_sb);
741 break;
742 }
743
744 if (de.ino && (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {
745 fattr.cf_uniqueid = de.ino;
746 } else {
747 fattr.cf_uniqueid = iunique(sb, ROOT_I);
748 cifs_autodisable_serverino(cifs_sb);
749 }
750
751 if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS) &&
752 couldbe_mf_symlink(&fattr))
753 /*
754 * trying to get the type and mode can be slow,
755 * so just call those regular files for now, and mark
756 * for reval
757 */
758 fattr.cf_flags |= CIFS_FATTR_NEED_REVAL;
759
760 cifs_prime_dcache(file->f_dentry, &name, &fattr);
761
762 ino = cifs_uniqueid_to_ino_t(fattr.cf_uniqueid);
763 return !dir_emit(ctx, name.name, name.len, ino, fattr.cf_dtype);
764}
765
766
767int cifs_readdir(struct file *file, struct dir_context *ctx)
768{
769 int rc = 0;
770 unsigned int xid;
771 int i;
772 struct cifs_tcon *tcon;
773 struct cifsFileInfo *cifsFile = NULL;
774 char *current_entry;
775 int num_to_fill = 0;
776 char *tmp_buf = NULL;
777 char *end_of_smb;
778 unsigned int max_len;
779
780 xid = get_xid();
781
782 /*
783 * Ensure FindFirst doesn't fail before doing filldir() for '.' and
784 * '..'. Otherwise we won't be able to notify VFS in case of failure.
785 */
786 if (file->private_data == NULL) {
787 rc = initiate_cifs_search(xid, file);
788 cifs_dbg(FYI, "initiate cifs search rc %d\n", rc);
789 if (rc)
790 goto rddir2_exit;
791 }
792
793 if (!dir_emit_dots(file, ctx))
794 goto rddir2_exit;
795
796 /* 1) If search is active,
797 is in current search buffer?
798 if it before then restart search
799 if after then keep searching till find it */
800
801 if (file->private_data == NULL) {
802 rc = -EINVAL;
803 goto rddir2_exit;
804 }
805 cifsFile = file->private_data;
806 if (cifsFile->srch_inf.endOfSearch) {
807 if (cifsFile->srch_inf.emptyDir) {
808 cifs_dbg(FYI, "End of search, empty dir\n");
809 rc = 0;
810 goto rddir2_exit;
811 }
812 } /* else {
813 cifsFile->invalidHandle = true;
814 tcon->ses->server->close(xid, tcon, &cifsFile->fid);
815 } */
816
817 tcon = tlink_tcon(cifsFile->tlink);
818 rc = find_cifs_entry(xid, tcon, ctx->pos, file, ¤t_entry,
819 &num_to_fill);
820 if (rc) {
821 cifs_dbg(FYI, "fce error %d\n", rc);
822 goto rddir2_exit;
823 } else if (current_entry != NULL) {
824 cifs_dbg(FYI, "entry %lld found\n", ctx->pos);
825 } else {
826 cifs_dbg(FYI, "could not find entry\n");
827 goto rddir2_exit;
828 }
829 cifs_dbg(FYI, "loop through %d times filling dir for net buf %p\n",
830 num_to_fill, cifsFile->srch_inf.ntwrk_buf_start);
831 max_len = tcon->ses->server->ops->calc_smb_size(
832 cifsFile->srch_inf.ntwrk_buf_start);
833 end_of_smb = cifsFile->srch_inf.ntwrk_buf_start + max_len;
834
835 tmp_buf = kmalloc(UNICODE_NAME_MAX, GFP_KERNEL);
836 if (tmp_buf == NULL) {
837 rc = -ENOMEM;
838 goto rddir2_exit;
839 }
840
841 for (i = 0; i < num_to_fill; i++) {
842 if (current_entry == NULL) {
843 /* evaluate whether this case is an error */
844 cifs_dbg(VFS, "past SMB end, num to fill %d i %d\n",
845 num_to_fill, i);
846 break;
847 }
848 /*
849 * if buggy server returns . and .. late do we want to
850 * check for that here?
851 */
852 rc = cifs_filldir(current_entry, file, ctx,
853 tmp_buf, max_len);
854 if (rc) {
855 if (rc > 0)
856 rc = 0;
857 break;
858 }
859
860 ctx->pos++;
861 if (ctx->pos ==
862 cifsFile->srch_inf.index_of_last_entry) {
863 cifs_dbg(FYI, "last entry in buf at pos %lld %s\n",
864 ctx->pos, tmp_buf);
865 cifs_save_resume_key(current_entry, cifsFile);
866 break;
867 } else
868 current_entry =
869 nxt_dir_entry(current_entry, end_of_smb,
870 cifsFile->srch_inf.info_level);
871 }
872 kfree(tmp_buf);
873
874rddir2_exit:
875 free_xid(xid);
876 return rc;
877}
1// SPDX-License-Identifier: LGPL-2.1
2/*
3 * fs/cifs/readdir.c
4 *
5 * Directory search handling
6 *
7 * Copyright (C) International Business Machines Corp., 2004, 2008
8 * Copyright (C) Red Hat, Inc., 2011
9 * Author(s): Steve French (sfrench@us.ibm.com)
10 *
11 */
12#include <linux/fs.h>
13#include <linux/pagemap.h>
14#include <linux/slab.h>
15#include <linux/stat.h>
16#include "cifspdu.h"
17#include "cifsglob.h"
18#include "cifsproto.h"
19#include "cifs_unicode.h"
20#include "cifs_debug.h"
21#include "cifs_fs_sb.h"
22#include "cifsfs.h"
23#include "smb2proto.h"
24#include "fs_context.h"
25
26/*
27 * To be safe - for UCS to UTF-8 with strings loaded with the rare long
28 * characters alloc more to account for such multibyte target UTF-8
29 * characters.
30 */
31#define UNICODE_NAME_MAX ((4 * NAME_MAX) + 2)
32
33#ifdef CONFIG_CIFS_DEBUG2
34static void dump_cifs_file_struct(struct file *file, char *label)
35{
36 struct cifsFileInfo *cf;
37
38 if (file) {
39 cf = file->private_data;
40 if (cf == NULL) {
41 cifs_dbg(FYI, "empty cifs private file data\n");
42 return;
43 }
44 if (cf->invalidHandle)
45 cifs_dbg(FYI, "Invalid handle\n");
46 if (cf->srch_inf.endOfSearch)
47 cifs_dbg(FYI, "end of search\n");
48 if (cf->srch_inf.emptyDir)
49 cifs_dbg(FYI, "empty dir\n");
50 }
51}
52#else
53static inline void dump_cifs_file_struct(struct file *file, char *label)
54{
55}
56#endif /* DEBUG2 */
57
58/*
59 * Attempt to preload the dcache with the results from the FIND_FIRST/NEXT
60 *
61 * Find the dentry that matches "name". If there isn't one, create one. If it's
62 * a negative dentry or the uniqueid or filetype(mode) changed,
63 * then drop it and recreate it.
64 */
65static void
66cifs_prime_dcache(struct dentry *parent, struct qstr *name,
67 struct cifs_fattr *fattr)
68{
69 struct dentry *dentry, *alias;
70 struct inode *inode;
71 struct super_block *sb = parent->d_sb;
72 struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
73 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);
74
75 cifs_dbg(FYI, "%s: for %s\n", __func__, name->name);
76
77 dentry = d_hash_and_lookup(parent, name);
78 if (!dentry) {
79 /*
80 * If we know that the inode will need to be revalidated
81 * immediately, then don't create a new dentry for it.
82 * We'll end up doing an on the wire call either way and
83 * this spares us an invalidation.
84 */
85 if (fattr->cf_flags & CIFS_FATTR_NEED_REVAL)
86 return;
87retry:
88 dentry = d_alloc_parallel(parent, name, &wq);
89 }
90 if (IS_ERR(dentry))
91 return;
92 if (!d_in_lookup(dentry)) {
93 inode = d_inode(dentry);
94 if (inode) {
95 if (d_mountpoint(dentry)) {
96 dput(dentry);
97 return;
98 }
99 /*
100 * If we're generating inode numbers, then we don't
101 * want to clobber the existing one with the one that
102 * the readdir code created.
103 */
104 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM))
105 fattr->cf_uniqueid = CIFS_I(inode)->uniqueid;
106
107 /* update inode in place
108 * if both i_ino and i_mode didn't change */
109 if (CIFS_I(inode)->uniqueid == fattr->cf_uniqueid &&
110 cifs_fattr_to_inode(inode, fattr) == 0) {
111 dput(dentry);
112 return;
113 }
114 }
115 d_invalidate(dentry);
116 dput(dentry);
117 goto retry;
118 } else {
119 inode = cifs_iget(sb, fattr);
120 if (!inode)
121 inode = ERR_PTR(-ENOMEM);
122 alias = d_splice_alias(inode, dentry);
123 d_lookup_done(dentry);
124 if (alias && !IS_ERR(alias))
125 dput(alias);
126 }
127 dput(dentry);
128}
129
130static bool reparse_file_needs_reval(const struct cifs_fattr *fattr)
131{
132 if (!(fattr->cf_cifsattrs & ATTR_REPARSE))
133 return false;
134 /*
135 * The DFS tags should be only intepreted by server side as per
136 * MS-FSCC 2.1.2.1, but let's include them anyway.
137 *
138 * Besides, if cf_cifstag is unset (0), then we still need it to be
139 * revalidated to know exactly what reparse point it is.
140 */
141 switch (fattr->cf_cifstag) {
142 case IO_REPARSE_TAG_DFS:
143 case IO_REPARSE_TAG_DFSR:
144 case IO_REPARSE_TAG_SYMLINK:
145 case IO_REPARSE_TAG_NFS:
146 case 0:
147 return true;
148 }
149 return false;
150}
151
152static void
153cifs_fill_common_info(struct cifs_fattr *fattr, struct cifs_sb_info *cifs_sb)
154{
155 fattr->cf_uid = cifs_sb->ctx->linux_uid;
156 fattr->cf_gid = cifs_sb->ctx->linux_gid;
157
158 /*
159 * The IO_REPARSE_TAG_LX_ tags originally were used by WSL but they
160 * are preferred by the Linux client in some cases since, unlike
161 * the NFS reparse tag (or EAs), they don't require an extra query
162 * to determine which type of special file they represent.
163 * TODO: go through all documented reparse tags to see if we can
164 * reasonably map some of them to directories vs. files vs. symlinks
165 */
166 if (fattr->cf_cifsattrs & ATTR_DIRECTORY) {
167 fattr->cf_mode = S_IFDIR | cifs_sb->ctx->dir_mode;
168 fattr->cf_dtype = DT_DIR;
169 } else if (fattr->cf_cifstag == IO_REPARSE_TAG_LX_SYMLINK) {
170 fattr->cf_mode |= S_IFLNK | cifs_sb->ctx->file_mode;
171 fattr->cf_dtype = DT_LNK;
172 } else if (fattr->cf_cifstag == IO_REPARSE_TAG_LX_FIFO) {
173 fattr->cf_mode |= S_IFIFO | cifs_sb->ctx->file_mode;
174 fattr->cf_dtype = DT_FIFO;
175 } else if (fattr->cf_cifstag == IO_REPARSE_TAG_AF_UNIX) {
176 fattr->cf_mode |= S_IFSOCK | cifs_sb->ctx->file_mode;
177 fattr->cf_dtype = DT_SOCK;
178 } else if (fattr->cf_cifstag == IO_REPARSE_TAG_LX_CHR) {
179 fattr->cf_mode |= S_IFCHR | cifs_sb->ctx->file_mode;
180 fattr->cf_dtype = DT_CHR;
181 } else if (fattr->cf_cifstag == IO_REPARSE_TAG_LX_BLK) {
182 fattr->cf_mode |= S_IFBLK | cifs_sb->ctx->file_mode;
183 fattr->cf_dtype = DT_BLK;
184 } else { /* TODO: should we mark some other reparse points (like DFSR) as directories? */
185 fattr->cf_mode = S_IFREG | cifs_sb->ctx->file_mode;
186 fattr->cf_dtype = DT_REG;
187 }
188
189 /*
190 * We need to revalidate it further to make a decision about whether it
191 * is a symbolic link, DFS referral or a reparse point with a direct
192 * access like junctions, deduplicated files, NFS symlinks.
193 */
194 if (reparse_file_needs_reval(fattr))
195 fattr->cf_flags |= CIFS_FATTR_NEED_REVAL;
196
197 /* non-unix readdir doesn't provide nlink */
198 fattr->cf_flags |= CIFS_FATTR_UNKNOWN_NLINK;
199
200 if (fattr->cf_cifsattrs & ATTR_READONLY)
201 fattr->cf_mode &= ~S_IWUGO;
202
203 /*
204 * We of course don't get ACL info in FIND_FIRST/NEXT results, so
205 * mark it for revalidation so that "ls -l" will look right. It might
206 * be super-slow, but if we don't do this then the ownership of files
207 * may look wrong since the inodes may not have timed out by the time
208 * "ls" does a stat() call on them.
209 */
210 if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_ACL) ||
211 (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MODE_FROM_SID))
212 fattr->cf_flags |= CIFS_FATTR_NEED_REVAL;
213
214 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL &&
215 fattr->cf_cifsattrs & ATTR_SYSTEM) {
216 if (fattr->cf_eof == 0) {
217 fattr->cf_mode &= ~S_IFMT;
218 fattr->cf_mode |= S_IFIFO;
219 fattr->cf_dtype = DT_FIFO;
220 } else {
221 /*
222 * trying to get the type and mode via SFU can be slow,
223 * so just call those regular files for now, and mark
224 * for reval
225 */
226 fattr->cf_flags |= CIFS_FATTR_NEED_REVAL;
227 }
228 }
229}
230
231/* Fill a cifs_fattr struct with info from SMB_FIND_FILE_POSIX_INFO. */
232static void
233cifs_posix_to_fattr(struct cifs_fattr *fattr, struct smb2_posix_info *info,
234 struct cifs_sb_info *cifs_sb)
235{
236 struct smb2_posix_info_parsed parsed;
237
238 posix_info_parse(info, NULL, &parsed);
239
240 memset(fattr, 0, sizeof(*fattr));
241 fattr->cf_uniqueid = le64_to_cpu(info->Inode);
242 fattr->cf_bytes = le64_to_cpu(info->AllocationSize);
243 fattr->cf_eof = le64_to_cpu(info->EndOfFile);
244
245 fattr->cf_atime = cifs_NTtimeToUnix(info->LastAccessTime);
246 fattr->cf_mtime = cifs_NTtimeToUnix(info->LastWriteTime);
247 fattr->cf_ctime = cifs_NTtimeToUnix(info->CreationTime);
248
249 fattr->cf_nlink = le32_to_cpu(info->HardLinks);
250 fattr->cf_cifsattrs = le32_to_cpu(info->DosAttributes);
251
252 /*
253 * Since we set the inode type below we need to mask off
254 * to avoid strange results if bits set above.
255 * XXX: why not make server&client use the type bits?
256 */
257 fattr->cf_mode = le32_to_cpu(info->Mode) & ~S_IFMT;
258
259 cifs_dbg(FYI, "posix fattr: dev %d, reparse %d, mode %o\n",
260 le32_to_cpu(info->DeviceId),
261 le32_to_cpu(info->ReparseTag),
262 le32_to_cpu(info->Mode));
263
264 if (fattr->cf_cifsattrs & ATTR_DIRECTORY) {
265 fattr->cf_mode |= S_IFDIR;
266 fattr->cf_dtype = DT_DIR;
267 } else {
268 /*
269 * mark anything that is not a dir as regular
270 * file. special files should have the REPARSE
271 * attribute and will be marked as needing revaluation
272 */
273 fattr->cf_mode |= S_IFREG;
274 fattr->cf_dtype = DT_REG;
275 }
276
277 if (reparse_file_needs_reval(fattr))
278 fattr->cf_flags |= CIFS_FATTR_NEED_REVAL;
279
280 sid_to_id(cifs_sb, &parsed.owner, fattr, SIDOWNER);
281 sid_to_id(cifs_sb, &parsed.group, fattr, SIDGROUP);
282}
283
284static void __dir_info_to_fattr(struct cifs_fattr *fattr, const void *info)
285{
286 const FILE_DIRECTORY_INFO *fi = info;
287
288 memset(fattr, 0, sizeof(*fattr));
289 fattr->cf_cifsattrs = le32_to_cpu(fi->ExtFileAttributes);
290 fattr->cf_eof = le64_to_cpu(fi->EndOfFile);
291 fattr->cf_bytes = le64_to_cpu(fi->AllocationSize);
292 fattr->cf_createtime = le64_to_cpu(fi->CreationTime);
293 fattr->cf_atime = cifs_NTtimeToUnix(fi->LastAccessTime);
294 fattr->cf_ctime = cifs_NTtimeToUnix(fi->ChangeTime);
295 fattr->cf_mtime = cifs_NTtimeToUnix(fi->LastWriteTime);
296}
297
298void
299cifs_dir_info_to_fattr(struct cifs_fattr *fattr, FILE_DIRECTORY_INFO *info,
300 struct cifs_sb_info *cifs_sb)
301{
302 __dir_info_to_fattr(fattr, info);
303 cifs_fill_common_info(fattr, cifs_sb);
304}
305
306static void cifs_fulldir_info_to_fattr(struct cifs_fattr *fattr,
307 SEARCH_ID_FULL_DIR_INFO *info,
308 struct cifs_sb_info *cifs_sb)
309{
310 __dir_info_to_fattr(fattr, info);
311
312 /* See MS-FSCC 2.4.19 FileIdFullDirectoryInformation */
313 if (fattr->cf_cifsattrs & ATTR_REPARSE)
314 fattr->cf_cifstag = le32_to_cpu(info->EaSize);
315 cifs_fill_common_info(fattr, cifs_sb);
316}
317
318static void
319cifs_std_info_to_fattr(struct cifs_fattr *fattr, FIND_FILE_STANDARD_INFO *info,
320 struct cifs_sb_info *cifs_sb)
321{
322 int offset = cifs_sb_master_tcon(cifs_sb)->ses->server->timeAdj;
323
324 memset(fattr, 0, sizeof(*fattr));
325 fattr->cf_atime = cnvrtDosUnixTm(info->LastAccessDate,
326 info->LastAccessTime, offset);
327 fattr->cf_ctime = cnvrtDosUnixTm(info->LastWriteDate,
328 info->LastWriteTime, offset);
329 fattr->cf_mtime = cnvrtDosUnixTm(info->LastWriteDate,
330 info->LastWriteTime, offset);
331
332 fattr->cf_cifsattrs = le16_to_cpu(info->Attributes);
333 fattr->cf_bytes = le32_to_cpu(info->AllocationSize);
334 fattr->cf_eof = le32_to_cpu(info->DataSize);
335
336 cifs_fill_common_info(fattr, cifs_sb);
337}
338
339/* BB eventually need to add the following helper function to
340 resolve NT_STATUS_STOPPED_ON_SYMLINK return code when
341 we try to do FindFirst on (NTFS) directory symlinks */
342/*
343int get_symlink_reparse_path(char *full_path, struct cifs_sb_info *cifs_sb,
344 unsigned int xid)
345{
346 __u16 fid;
347 int len;
348 int oplock = 0;
349 int rc;
350 struct cifs_tcon *ptcon = cifs_sb_tcon(cifs_sb);
351 char *tmpbuffer;
352
353 rc = CIFSSMBOpen(xid, ptcon, full_path, FILE_OPEN, GENERIC_READ,
354 OPEN_REPARSE_POINT, &fid, &oplock, NULL,
355 cifs_sb->local_nls,
356 cifs_remap(cifs_sb);
357 if (!rc) {
358 tmpbuffer = kmalloc(maxpath);
359 rc = CIFSSMBQueryReparseLinkInfo(xid, ptcon, full_path,
360 tmpbuffer,
361 maxpath -1,
362 fid,
363 cifs_sb->local_nls);
364 if (CIFSSMBClose(xid, ptcon, fid)) {
365 cifs_dbg(FYI, "Error closing temporary reparsepoint open\n");
366 }
367 }
368}
369 */
370
371static int
372_initiate_cifs_search(const unsigned int xid, struct file *file,
373 const char *full_path)
374{
375 __u16 search_flags;
376 int rc = 0;
377 struct cifsFileInfo *cifsFile;
378 struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file);
379 struct tcon_link *tlink = NULL;
380 struct cifs_tcon *tcon;
381 struct TCP_Server_Info *server;
382
383 if (file->private_data == NULL) {
384 tlink = cifs_sb_tlink(cifs_sb);
385 if (IS_ERR(tlink))
386 return PTR_ERR(tlink);
387
388 cifsFile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
389 if (cifsFile == NULL) {
390 rc = -ENOMEM;
391 goto error_exit;
392 }
393 spin_lock_init(&cifsFile->file_info_lock);
394 file->private_data = cifsFile;
395 cifsFile->tlink = cifs_get_tlink(tlink);
396 tcon = tlink_tcon(tlink);
397 } else {
398 cifsFile = file->private_data;
399 tcon = tlink_tcon(cifsFile->tlink);
400 }
401
402 server = tcon->ses->server;
403
404 if (!server->ops->query_dir_first) {
405 rc = -ENOSYS;
406 goto error_exit;
407 }
408
409 cifsFile->invalidHandle = true;
410 cifsFile->srch_inf.endOfSearch = false;
411
412 cifs_dbg(FYI, "Full path: %s start at: %lld\n", full_path, file->f_pos);
413
414ffirst_retry:
415 /* test for Unix extensions */
416 /* but now check for them on the share/mount not on the SMB session */
417 /* if (cap_unix(tcon->ses) { */
418 if (tcon->unix_ext)
419 cifsFile->srch_inf.info_level = SMB_FIND_FILE_UNIX;
420 else if (tcon->posix_extensions)
421 cifsFile->srch_inf.info_level = SMB_FIND_FILE_POSIX_INFO;
422 else if ((tcon->ses->capabilities &
423 tcon->ses->server->vals->cap_nt_find) == 0) {
424 cifsFile->srch_inf.info_level = SMB_FIND_FILE_INFO_STANDARD;
425 } else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) {
426 cifsFile->srch_inf.info_level = SMB_FIND_FILE_ID_FULL_DIR_INFO;
427 } else /* not srvinos - BB fixme add check for backlevel? */ {
428 cifsFile->srch_inf.info_level = SMB_FIND_FILE_DIRECTORY_INFO;
429 }
430
431 search_flags = CIFS_SEARCH_CLOSE_AT_END | CIFS_SEARCH_RETURN_RESUME;
432 if (backup_cred(cifs_sb))
433 search_flags |= CIFS_SEARCH_BACKUP_SEARCH;
434
435 rc = server->ops->query_dir_first(xid, tcon, full_path, cifs_sb,
436 &cifsFile->fid, search_flags,
437 &cifsFile->srch_inf);
438
439 if (rc == 0)
440 cifsFile->invalidHandle = false;
441 /* BB add following call to handle readdir on new NTFS symlink errors
442 else if STATUS_STOPPED_ON_SYMLINK
443 call get_symlink_reparse_path and retry with new path */
444 else if ((rc == -EOPNOTSUPP) &&
445 (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {
446 cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM;
447 goto ffirst_retry;
448 }
449error_exit:
450 cifs_put_tlink(tlink);
451 return rc;
452}
453
454static int
455initiate_cifs_search(const unsigned int xid, struct file *file,
456 const char *full_path)
457{
458 int rc, retry_count = 0;
459
460 do {
461 rc = _initiate_cifs_search(xid, file, full_path);
462 /*
463 * If we don't have enough credits to start reading the
464 * directory just try again after short wait.
465 */
466 if (rc != -EDEADLK)
467 break;
468
469 usleep_range(512, 2048);
470 } while (retry_count++ < 5);
471
472 return rc;
473}
474
475/* return length of unicode string in bytes */
476static int cifs_unicode_bytelen(const char *str)
477{
478 int len;
479 const __le16 *ustr = (const __le16 *)str;
480
481 for (len = 0; len <= PATH_MAX; len++) {
482 if (ustr[len] == 0)
483 return len << 1;
484 }
485 cifs_dbg(FYI, "Unicode string longer than PATH_MAX found\n");
486 return len << 1;
487}
488
489static char *nxt_dir_entry(char *old_entry, char *end_of_smb, int level)
490{
491 char *new_entry;
492 FILE_DIRECTORY_INFO *pDirInfo = (FILE_DIRECTORY_INFO *)old_entry;
493
494 if (level == SMB_FIND_FILE_INFO_STANDARD) {
495 FIND_FILE_STANDARD_INFO *pfData;
496 pfData = (FIND_FILE_STANDARD_INFO *)pDirInfo;
497
498 new_entry = old_entry + sizeof(FIND_FILE_STANDARD_INFO) +
499 pfData->FileNameLength;
500 } else {
501 u32 next_offset = le32_to_cpu(pDirInfo->NextEntryOffset);
502
503 if (old_entry + next_offset < old_entry) {
504 cifs_dbg(VFS, "Invalid offset %u\n", next_offset);
505 return NULL;
506 }
507 new_entry = old_entry + next_offset;
508 }
509 cifs_dbg(FYI, "new entry %p old entry %p\n", new_entry, old_entry);
510 /* validate that new_entry is not past end of SMB */
511 if (new_entry >= end_of_smb) {
512 cifs_dbg(VFS, "search entry %p began after end of SMB %p old entry %p\n",
513 new_entry, end_of_smb, old_entry);
514 return NULL;
515 } else if (((level == SMB_FIND_FILE_INFO_STANDARD) &&
516 (new_entry + sizeof(FIND_FILE_STANDARD_INFO) > end_of_smb))
517 || ((level != SMB_FIND_FILE_INFO_STANDARD) &&
518 (new_entry + sizeof(FILE_DIRECTORY_INFO) > end_of_smb))) {
519 cifs_dbg(VFS, "search entry %p extends after end of SMB %p\n",
520 new_entry, end_of_smb);
521 return NULL;
522 } else
523 return new_entry;
524
525}
526
527struct cifs_dirent {
528 const char *name;
529 size_t namelen;
530 u32 resume_key;
531 u64 ino;
532};
533
534static void cifs_fill_dirent_posix(struct cifs_dirent *de,
535 const struct smb2_posix_info *info)
536{
537 struct smb2_posix_info_parsed parsed;
538
539 /* payload should have already been checked at this point */
540 if (posix_info_parse(info, NULL, &parsed) < 0) {
541 cifs_dbg(VFS, "Invalid POSIX info payload\n");
542 return;
543 }
544
545 de->name = parsed.name;
546 de->namelen = parsed.name_len;
547 de->resume_key = info->Ignored;
548 de->ino = le64_to_cpu(info->Inode);
549}
550
551static void cifs_fill_dirent_unix(struct cifs_dirent *de,
552 const FILE_UNIX_INFO *info, bool is_unicode)
553{
554 de->name = &info->FileName[0];
555 if (is_unicode)
556 de->namelen = cifs_unicode_bytelen(de->name);
557 else
558 de->namelen = strnlen(de->name, PATH_MAX);
559 de->resume_key = info->ResumeKey;
560 de->ino = le64_to_cpu(info->basic.UniqueId);
561}
562
563static void cifs_fill_dirent_dir(struct cifs_dirent *de,
564 const FILE_DIRECTORY_INFO *info)
565{
566 de->name = &info->FileName[0];
567 de->namelen = le32_to_cpu(info->FileNameLength);
568 de->resume_key = info->FileIndex;
569}
570
571static void cifs_fill_dirent_full(struct cifs_dirent *de,
572 const FILE_FULL_DIRECTORY_INFO *info)
573{
574 de->name = &info->FileName[0];
575 de->namelen = le32_to_cpu(info->FileNameLength);
576 de->resume_key = info->FileIndex;
577}
578
579static void cifs_fill_dirent_search(struct cifs_dirent *de,
580 const SEARCH_ID_FULL_DIR_INFO *info)
581{
582 de->name = &info->FileName[0];
583 de->namelen = le32_to_cpu(info->FileNameLength);
584 de->resume_key = info->FileIndex;
585 de->ino = le64_to_cpu(info->UniqueId);
586}
587
588static void cifs_fill_dirent_both(struct cifs_dirent *de,
589 const FILE_BOTH_DIRECTORY_INFO *info)
590{
591 de->name = &info->FileName[0];
592 de->namelen = le32_to_cpu(info->FileNameLength);
593 de->resume_key = info->FileIndex;
594}
595
596static void cifs_fill_dirent_std(struct cifs_dirent *de,
597 const FIND_FILE_STANDARD_INFO *info)
598{
599 de->name = &info->FileName[0];
600 /* one byte length, no endianess conversion */
601 de->namelen = info->FileNameLength;
602 de->resume_key = info->ResumeKey;
603}
604
605static int cifs_fill_dirent(struct cifs_dirent *de, const void *info,
606 u16 level, bool is_unicode)
607{
608 memset(de, 0, sizeof(*de));
609
610 switch (level) {
611 case SMB_FIND_FILE_POSIX_INFO:
612 cifs_fill_dirent_posix(de, info);
613 break;
614 case SMB_FIND_FILE_UNIX:
615 cifs_fill_dirent_unix(de, info, is_unicode);
616 break;
617 case SMB_FIND_FILE_DIRECTORY_INFO:
618 cifs_fill_dirent_dir(de, info);
619 break;
620 case SMB_FIND_FILE_FULL_DIRECTORY_INFO:
621 cifs_fill_dirent_full(de, info);
622 break;
623 case SMB_FIND_FILE_ID_FULL_DIR_INFO:
624 cifs_fill_dirent_search(de, info);
625 break;
626 case SMB_FIND_FILE_BOTH_DIRECTORY_INFO:
627 cifs_fill_dirent_both(de, info);
628 break;
629 case SMB_FIND_FILE_INFO_STANDARD:
630 cifs_fill_dirent_std(de, info);
631 break;
632 default:
633 cifs_dbg(FYI, "Unknown findfirst level %d\n", level);
634 return -EINVAL;
635 }
636
637 return 0;
638}
639
640#define UNICODE_DOT cpu_to_le16(0x2e)
641
642/* return 0 if no match and 1 for . (current directory) and 2 for .. (parent) */
643static int cifs_entry_is_dot(struct cifs_dirent *de, bool is_unicode)
644{
645 int rc = 0;
646
647 if (!de->name)
648 return 0;
649
650 if (is_unicode) {
651 __le16 *ufilename = (__le16 *)de->name;
652 if (de->namelen == 2) {
653 /* check for . */
654 if (ufilename[0] == UNICODE_DOT)
655 rc = 1;
656 } else if (de->namelen == 4) {
657 /* check for .. */
658 if (ufilename[0] == UNICODE_DOT &&
659 ufilename[1] == UNICODE_DOT)
660 rc = 2;
661 }
662 } else /* ASCII */ {
663 if (de->namelen == 1) {
664 if (de->name[0] == '.')
665 rc = 1;
666 } else if (de->namelen == 2) {
667 if (de->name[0] == '.' && de->name[1] == '.')
668 rc = 2;
669 }
670 }
671
672 return rc;
673}
674
675/* Check if directory that we are searching has changed so we can decide
676 whether we can use the cached search results from the previous search */
677static int is_dir_changed(struct file *file)
678{
679 struct inode *inode = file_inode(file);
680 struct cifsInodeInfo *cifsInfo = CIFS_I(inode);
681
682 if (cifsInfo->time == 0)
683 return 1; /* directory was changed, perhaps due to unlink */
684 else
685 return 0;
686
687}
688
689static int cifs_save_resume_key(const char *current_entry,
690 struct cifsFileInfo *file_info)
691{
692 struct cifs_dirent de;
693 int rc;
694
695 rc = cifs_fill_dirent(&de, current_entry, file_info->srch_inf.info_level,
696 file_info->srch_inf.unicode);
697 if (!rc) {
698 file_info->srch_inf.presume_name = de.name;
699 file_info->srch_inf.resume_name_len = de.namelen;
700 file_info->srch_inf.resume_key = de.resume_key;
701 }
702 return rc;
703}
704
705/*
706 * Find the corresponding entry in the search. Note that the SMB server returns
707 * search entries for . and .. which complicates logic here if we choose to
708 * parse for them and we do not assume that they are located in the findfirst
709 * return buffer. We start counting in the buffer with entry 2 and increment for
710 * every entry (do not increment for . or .. entry).
711 */
712static int
713find_cifs_entry(const unsigned int xid, struct cifs_tcon *tcon, loff_t pos,
714 struct file *file, const char *full_path,
715 char **current_entry, int *num_to_ret)
716{
717 __u16 search_flags;
718 int rc = 0;
719 int pos_in_buf = 0;
720 loff_t first_entry_in_buffer;
721 loff_t index_to_find = pos;
722 struct cifsFileInfo *cfile = file->private_data;
723 struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file);
724 struct TCP_Server_Info *server = tcon->ses->server;
725 /* check if index in the buffer */
726
727 if (!server->ops->query_dir_first || !server->ops->query_dir_next)
728 return -ENOSYS;
729
730 if ((cfile == NULL) || (current_entry == NULL) || (num_to_ret == NULL))
731 return -ENOENT;
732
733 *current_entry = NULL;
734 first_entry_in_buffer = cfile->srch_inf.index_of_last_entry -
735 cfile->srch_inf.entries_in_buffer;
736
737 /*
738 * If first entry in buf is zero then is first buffer
739 * in search response data which means it is likely . and ..
740 * will be in this buffer, although some servers do not return
741 * . and .. for the root of a drive and for those we need
742 * to start two entries earlier.
743 */
744
745 dump_cifs_file_struct(file, "In fce ");
746 if (((index_to_find < cfile->srch_inf.index_of_last_entry) &&
747 is_dir_changed(file)) || (index_to_find < first_entry_in_buffer)) {
748 /* close and restart search */
749 cifs_dbg(FYI, "search backing up - close and restart search\n");
750 spin_lock(&cfile->file_info_lock);
751 if (server->ops->dir_needs_close(cfile)) {
752 cfile->invalidHandle = true;
753 spin_unlock(&cfile->file_info_lock);
754 if (server->ops->close_dir)
755 server->ops->close_dir(xid, tcon, &cfile->fid);
756 } else
757 spin_unlock(&cfile->file_info_lock);
758 if (cfile->srch_inf.ntwrk_buf_start) {
759 cifs_dbg(FYI, "freeing SMB ff cache buf on search rewind\n");
760 if (cfile->srch_inf.smallBuf)
761 cifs_small_buf_release(cfile->srch_inf.
762 ntwrk_buf_start);
763 else
764 cifs_buf_release(cfile->srch_inf.
765 ntwrk_buf_start);
766 cfile->srch_inf.ntwrk_buf_start = NULL;
767 }
768 rc = initiate_cifs_search(xid, file, full_path);
769 if (rc) {
770 cifs_dbg(FYI, "error %d reinitiating a search on rewind\n",
771 rc);
772 return rc;
773 }
774 /* FindFirst/Next set last_entry to NULL on malformed reply */
775 if (cfile->srch_inf.last_entry)
776 cifs_save_resume_key(cfile->srch_inf.last_entry, cfile);
777 }
778
779 search_flags = CIFS_SEARCH_CLOSE_AT_END | CIFS_SEARCH_RETURN_RESUME;
780 if (backup_cred(cifs_sb))
781 search_flags |= CIFS_SEARCH_BACKUP_SEARCH;
782
783 while ((index_to_find >= cfile->srch_inf.index_of_last_entry) &&
784 (rc == 0) && !cfile->srch_inf.endOfSearch) {
785 cifs_dbg(FYI, "calling findnext2\n");
786 rc = server->ops->query_dir_next(xid, tcon, &cfile->fid,
787 search_flags,
788 &cfile->srch_inf);
789 /* FindFirst/Next set last_entry to NULL on malformed reply */
790 if (cfile->srch_inf.last_entry)
791 cifs_save_resume_key(cfile->srch_inf.last_entry, cfile);
792 if (rc)
793 return -ENOENT;
794 }
795 if (index_to_find < cfile->srch_inf.index_of_last_entry) {
796 /* we found the buffer that contains the entry */
797 /* scan and find it */
798 int i;
799 char *cur_ent;
800 char *end_of_smb;
801
802 if (cfile->srch_inf.ntwrk_buf_start == NULL) {
803 cifs_dbg(VFS, "ntwrk_buf_start is NULL during readdir\n");
804 return -EIO;
805 }
806
807 end_of_smb = cfile->srch_inf.ntwrk_buf_start +
808 server->ops->calc_smb_size(
809 cfile->srch_inf.ntwrk_buf_start,
810 server);
811
812 cur_ent = cfile->srch_inf.srch_entries_start;
813 first_entry_in_buffer = cfile->srch_inf.index_of_last_entry
814 - cfile->srch_inf.entries_in_buffer;
815 pos_in_buf = index_to_find - first_entry_in_buffer;
816 cifs_dbg(FYI, "found entry - pos_in_buf %d\n", pos_in_buf);
817
818 for (i = 0; (i < (pos_in_buf)) && (cur_ent != NULL); i++) {
819 /* go entry by entry figuring out which is first */
820 cur_ent = nxt_dir_entry(cur_ent, end_of_smb,
821 cfile->srch_inf.info_level);
822 }
823 if ((cur_ent == NULL) && (i < pos_in_buf)) {
824 /* BB fixme - check if we should flag this error */
825 cifs_dbg(VFS, "reached end of buf searching for pos in buf %d index to find %lld rc %d\n",
826 pos_in_buf, index_to_find, rc);
827 }
828 rc = 0;
829 *current_entry = cur_ent;
830 } else {
831 cifs_dbg(FYI, "index not in buffer - could not findnext into it\n");
832 return 0;
833 }
834
835 if (pos_in_buf >= cfile->srch_inf.entries_in_buffer) {
836 cifs_dbg(FYI, "can not return entries pos_in_buf beyond last\n");
837 *num_to_ret = 0;
838 } else
839 *num_to_ret = cfile->srch_inf.entries_in_buffer - pos_in_buf;
840
841 return rc;
842}
843
844static int cifs_filldir(char *find_entry, struct file *file,
845 struct dir_context *ctx,
846 char *scratch_buf, unsigned int max_len)
847{
848 struct cifsFileInfo *file_info = file->private_data;
849 struct super_block *sb = file_inode(file)->i_sb;
850 struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
851 struct cifs_dirent de = { NULL, };
852 struct cifs_fattr fattr;
853 struct qstr name;
854 int rc = 0;
855 ino_t ino;
856
857 rc = cifs_fill_dirent(&de, find_entry, file_info->srch_inf.info_level,
858 file_info->srch_inf.unicode);
859 if (rc)
860 return rc;
861
862 if (de.namelen > max_len) {
863 cifs_dbg(VFS, "bad search response length %zd past smb end\n",
864 de.namelen);
865 return -EINVAL;
866 }
867
868 /* skip . and .. since we added them first */
869 if (cifs_entry_is_dot(&de, file_info->srch_inf.unicode))
870 return 0;
871
872 if (file_info->srch_inf.unicode) {
873 struct nls_table *nlt = cifs_sb->local_nls;
874 int map_type;
875
876 map_type = cifs_remap(cifs_sb);
877 name.name = scratch_buf;
878 name.len =
879 cifs_from_utf16((char *)name.name, (__le16 *)de.name,
880 UNICODE_NAME_MAX,
881 min_t(size_t, de.namelen,
882 (size_t)max_len), nlt, map_type);
883 name.len -= nls_nullsize(nlt);
884 } else {
885 name.name = de.name;
886 name.len = de.namelen;
887 }
888
889 switch (file_info->srch_inf.info_level) {
890 case SMB_FIND_FILE_POSIX_INFO:
891 cifs_posix_to_fattr(&fattr,
892 (struct smb2_posix_info *)find_entry,
893 cifs_sb);
894 break;
895 case SMB_FIND_FILE_UNIX:
896 cifs_unix_basic_to_fattr(&fattr,
897 &((FILE_UNIX_INFO *)find_entry)->basic,
898 cifs_sb);
899 break;
900 case SMB_FIND_FILE_INFO_STANDARD:
901 cifs_std_info_to_fattr(&fattr,
902 (FIND_FILE_STANDARD_INFO *)find_entry,
903 cifs_sb);
904 break;
905 case SMB_FIND_FILE_ID_FULL_DIR_INFO:
906 cifs_fulldir_info_to_fattr(&fattr,
907 (SEARCH_ID_FULL_DIR_INFO *)find_entry,
908 cifs_sb);
909 break;
910 default:
911 cifs_dir_info_to_fattr(&fattr,
912 (FILE_DIRECTORY_INFO *)find_entry,
913 cifs_sb);
914 break;
915 }
916
917 if (de.ino && (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {
918 fattr.cf_uniqueid = de.ino;
919 } else {
920 fattr.cf_uniqueid = iunique(sb, ROOT_I);
921 cifs_autodisable_serverino(cifs_sb);
922 }
923
924 if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS) &&
925 couldbe_mf_symlink(&fattr))
926 /*
927 * trying to get the type and mode can be slow,
928 * so just call those regular files for now, and mark
929 * for reval
930 */
931 fattr.cf_flags |= CIFS_FATTR_NEED_REVAL;
932
933 cifs_prime_dcache(file_dentry(file), &name, &fattr);
934
935 ino = cifs_uniqueid_to_ino_t(fattr.cf_uniqueid);
936 return !dir_emit(ctx, name.name, name.len, ino, fattr.cf_dtype);
937}
938
939
940int cifs_readdir(struct file *file, struct dir_context *ctx)
941{
942 int rc = 0;
943 unsigned int xid;
944 int i;
945 struct cifs_tcon *tcon;
946 struct cifsFileInfo *cifsFile = NULL;
947 char *current_entry;
948 int num_to_fill = 0;
949 char *tmp_buf = NULL;
950 char *end_of_smb;
951 unsigned int max_len;
952 const char *full_path;
953 void *page = alloc_dentry_path();
954
955 xid = get_xid();
956
957 full_path = build_path_from_dentry(file_dentry(file), page);
958 if (IS_ERR(full_path)) {
959 rc = PTR_ERR(full_path);
960 goto rddir2_exit;
961 }
962
963 /*
964 * Ensure FindFirst doesn't fail before doing filldir() for '.' and
965 * '..'. Otherwise we won't be able to notify VFS in case of failure.
966 */
967 if (file->private_data == NULL) {
968 rc = initiate_cifs_search(xid, file, full_path);
969 cifs_dbg(FYI, "initiate cifs search rc %d\n", rc);
970 if (rc)
971 goto rddir2_exit;
972 }
973
974 if (!dir_emit_dots(file, ctx))
975 goto rddir2_exit;
976
977 /* 1) If search is active,
978 is in current search buffer?
979 if it before then restart search
980 if after then keep searching till find it */
981
982 cifsFile = file->private_data;
983 if (cifsFile->srch_inf.endOfSearch) {
984 if (cifsFile->srch_inf.emptyDir) {
985 cifs_dbg(FYI, "End of search, empty dir\n");
986 rc = 0;
987 goto rddir2_exit;
988 }
989 } /* else {
990 cifsFile->invalidHandle = true;
991 tcon->ses->server->close(xid, tcon, &cifsFile->fid);
992 } */
993
994 tcon = tlink_tcon(cifsFile->tlink);
995 rc = find_cifs_entry(xid, tcon, ctx->pos, file, full_path,
996 ¤t_entry, &num_to_fill);
997 if (rc) {
998 cifs_dbg(FYI, "fce error %d\n", rc);
999 goto rddir2_exit;
1000 } else if (current_entry != NULL) {
1001 cifs_dbg(FYI, "entry %lld found\n", ctx->pos);
1002 } else {
1003 cifs_dbg(FYI, "Could not find entry\n");
1004 goto rddir2_exit;
1005 }
1006 cifs_dbg(FYI, "loop through %d times filling dir for net buf %p\n",
1007 num_to_fill, cifsFile->srch_inf.ntwrk_buf_start);
1008 max_len = tcon->ses->server->ops->calc_smb_size(
1009 cifsFile->srch_inf.ntwrk_buf_start,
1010 tcon->ses->server);
1011 end_of_smb = cifsFile->srch_inf.ntwrk_buf_start + max_len;
1012
1013 tmp_buf = kmalloc(UNICODE_NAME_MAX, GFP_KERNEL);
1014 if (tmp_buf == NULL) {
1015 rc = -ENOMEM;
1016 goto rddir2_exit;
1017 }
1018
1019 for (i = 0; i < num_to_fill; i++) {
1020 if (current_entry == NULL) {
1021 /* evaluate whether this case is an error */
1022 cifs_dbg(VFS, "past SMB end, num to fill %d i %d\n",
1023 num_to_fill, i);
1024 break;
1025 }
1026 /*
1027 * if buggy server returns . and .. late do we want to
1028 * check for that here?
1029 */
1030 *tmp_buf = 0;
1031 rc = cifs_filldir(current_entry, file, ctx,
1032 tmp_buf, max_len);
1033 if (rc) {
1034 if (rc > 0)
1035 rc = 0;
1036 break;
1037 }
1038
1039 ctx->pos++;
1040 if (ctx->pos ==
1041 cifsFile->srch_inf.index_of_last_entry) {
1042 cifs_dbg(FYI, "last entry in buf at pos %lld %s\n",
1043 ctx->pos, tmp_buf);
1044 cifs_save_resume_key(current_entry, cifsFile);
1045 break;
1046 } else
1047 current_entry =
1048 nxt_dir_entry(current_entry, end_of_smb,
1049 cifsFile->srch_inf.info_level);
1050 }
1051 kfree(tmp_buf);
1052
1053rddir2_exit:
1054 free_dentry_path(page);
1055 free_xid(xid);
1056 return rc;
1057}