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