Commit | Line | Data |
---|---|---|
e9be9d5e MS |
1 | /* |
2 | * | |
3 | * Copyright (C) 2011 Novell Inc. | |
4 | * | |
5 | * This program is free software; you can redistribute it and/or modify it | |
6 | * under the terms of the GNU General Public License version 2 as published by | |
7 | * the Free Software Foundation. | |
8 | */ | |
9 | ||
10 | #include <linux/fs.h> | |
11 | #include <linux/namei.h> | |
12 | #include <linux/xattr.h> | |
13 | #include <linux/security.h> | |
14 | #include <linux/cred.h> | |
3ea22a71 | 15 | #include <linux/module.h> |
38b25697 MS |
16 | #include <linux/posix_acl.h> |
17 | #include <linux/posix_acl_xattr.h> | |
6a45b362 | 18 | #include <linux/atomic.h> |
a6c60655 | 19 | #include <linux/ratelimit.h> |
e9be9d5e MS |
20 | #include "overlayfs.h" |
21 | ||
3ea22a71 MS |
22 | static unsigned short ovl_redirect_max = 256; |
23 | module_param_named(redirect_max, ovl_redirect_max, ushort, 0644); | |
24 | MODULE_PARM_DESC(ovl_redirect_max, | |
25 | "Maximum length of absolute redirect xattr value"); | |
26 | ||
4120fe64 VG |
27 | static int ovl_set_redirect(struct dentry *dentry, bool samedir); |
28 | ||
415543d5 | 29 | int ovl_cleanup(struct inode *wdir, struct dentry *wdentry) |
e9be9d5e MS |
30 | { |
31 | int err; | |
32 | ||
33 | dget(wdentry); | |
e36cb0b8 | 34 | if (d_is_dir(wdentry)) |
e9be9d5e MS |
35 | err = ovl_do_rmdir(wdir, wdentry); |
36 | else | |
37 | err = ovl_do_unlink(wdir, wdentry); | |
38 | dput(wdentry); | |
39 | ||
40 | if (err) { | |
41 | pr_err("overlayfs: cleanup of '%pd2' failed (%i)\n", | |
42 | wdentry, err); | |
43 | } | |
415543d5 AG |
44 | |
45 | return err; | |
e9be9d5e MS |
46 | } |
47 | ||
137ec526 | 48 | static struct dentry *ovl_lookup_temp(struct dentry *workdir) |
e9be9d5e MS |
49 | { |
50 | struct dentry *temp; | |
51 | char name[20]; | |
6a45b362 | 52 | static atomic_t temp_id = ATOMIC_INIT(0); |
e9be9d5e | 53 | |
6a45b362 RW |
54 | /* counter is allowed to wrap, since temp dentries are ephemeral */ |
55 | snprintf(name, sizeof(name), "#%x", atomic_inc_return(&temp_id)); | |
e9be9d5e MS |
56 | |
57 | temp = lookup_one_len(name, workdir, strlen(name)); | |
58 | if (!IS_ERR(temp) && temp->d_inode) { | |
59 | pr_err("overlayfs: workdir/%s already exists\n", name); | |
60 | dput(temp); | |
61 | temp = ERR_PTR(-EIO); | |
62 | } | |
63 | ||
64 | return temp; | |
65 | } | |
66 | ||
67 | /* caller holds i_mutex on workdir */ | |
e7dd0e71 | 68 | static struct dentry *ovl_whiteout(struct dentry *workdir) |
e9be9d5e MS |
69 | { |
70 | int err; | |
71 | struct dentry *whiteout; | |
72 | struct inode *wdir = workdir->d_inode; | |
73 | ||
3d27573c | 74 | whiteout = ovl_lookup_temp(workdir); |
e9be9d5e MS |
75 | if (IS_ERR(whiteout)) |
76 | return whiteout; | |
77 | ||
78 | err = ovl_do_whiteout(wdir, whiteout); | |
79 | if (err) { | |
80 | dput(whiteout); | |
81 | whiteout = ERR_PTR(err); | |
82 | } | |
83 | ||
84 | return whiteout; | |
85 | } | |
86 | ||
e7dd0e71 AG |
87 | /* Caller must hold i_mutex on both workdir and dir */ |
88 | int ovl_cleanup_and_whiteout(struct dentry *workdir, struct inode *dir, | |
89 | struct dentry *dentry) | |
90 | { | |
91 | struct inode *wdir = workdir->d_inode; | |
92 | struct dentry *whiteout; | |
93 | int err; | |
94 | int flags = 0; | |
95 | ||
96 | whiteout = ovl_whiteout(workdir); | |
97 | err = PTR_ERR(whiteout); | |
98 | if (IS_ERR(whiteout)) | |
99 | return err; | |
100 | ||
101 | if (d_is_dir(dentry)) | |
102 | flags = RENAME_EXCHANGE; | |
103 | ||
104 | err = ovl_do_rename(wdir, whiteout, dir, dentry, flags); | |
105 | if (err) | |
106 | goto kill_whiteout; | |
107 | if (flags) | |
108 | ovl_cleanup(wdir, dentry); | |
109 | ||
110 | out: | |
111 | dput(whiteout); | |
112 | return err; | |
113 | ||
114 | kill_whiteout: | |
115 | ovl_cleanup(wdir, whiteout); | |
116 | goto out; | |
117 | } | |
118 | ||
f73cc77c AV |
119 | static int ovl_mkdir_real(struct inode *dir, struct dentry **newdentry, |
120 | umode_t mode) | |
121 | { | |
122 | int err; | |
123 | struct dentry *d, *dentry = *newdentry; | |
124 | ||
125 | err = ovl_do_mkdir(dir, dentry, mode); | |
126 | if (err) | |
127 | return err; | |
128 | ||
129 | if (likely(!d_unhashed(dentry))) | |
130 | return 0; | |
131 | ||
132 | /* | |
133 | * vfs_mkdir() may succeed and leave the dentry passed | |
134 | * to it unhashed and negative. If that happens, try to | |
135 | * lookup a new hashed and positive dentry. | |
136 | */ | |
137 | d = lookup_one_len(dentry->d_name.name, dentry->d_parent, | |
138 | dentry->d_name.len); | |
139 | if (IS_ERR(d)) { | |
140 | pr_warn("overlayfs: failed lookup after mkdir (%pd2, err=%i).\n", | |
141 | dentry, err); | |
142 | return PTR_ERR(d); | |
143 | } | |
144 | dput(dentry); | |
145 | *newdentry = d; | |
146 | ||
147 | return 0; | |
148 | } | |
149 | ||
95a1c815 MS |
150 | struct dentry *ovl_create_real(struct inode *dir, struct dentry *newdentry, |
151 | struct ovl_cattr *attr) | |
e9be9d5e MS |
152 | { |
153 | int err; | |
154 | ||
95a1c815 MS |
155 | if (IS_ERR(newdentry)) |
156 | return newdentry; | |
157 | ||
158 | err = -ESTALE; | |
e9be9d5e | 159 | if (newdentry->d_inode) |
95a1c815 | 160 | goto out; |
e9be9d5e | 161 | |
471ec5dc AG |
162 | if (attr->hardlink) { |
163 | err = ovl_do_link(attr->hardlink, dir, newdentry); | |
e9be9d5e | 164 | } else { |
32a3d848 | 165 | switch (attr->mode & S_IFMT) { |
e9be9d5e | 166 | case S_IFREG: |
6cf00764 | 167 | err = ovl_do_create(dir, newdentry, attr->mode); |
e9be9d5e MS |
168 | break; |
169 | ||
170 | case S_IFDIR: | |
f73cc77c AV |
171 | /* mkdir is special... */ |
172 | err = ovl_mkdir_real(dir, &newdentry, attr->mode); | |
e9be9d5e MS |
173 | break; |
174 | ||
175 | case S_IFCHR: | |
176 | case S_IFBLK: | |
177 | case S_IFIFO: | |
178 | case S_IFSOCK: | |
6cf00764 AG |
179 | err = ovl_do_mknod(dir, newdentry, attr->mode, |
180 | attr->rdev); | |
e9be9d5e MS |
181 | break; |
182 | ||
183 | case S_IFLNK: | |
6cf00764 | 184 | err = ovl_do_symlink(dir, newdentry, attr->link); |
e9be9d5e MS |
185 | break; |
186 | ||
187 | default: | |
188 | err = -EPERM; | |
189 | } | |
190 | } | |
191 | if (!err && WARN_ON(!newdentry->d_inode)) { | |
192 | /* | |
193 | * Not quite sure if non-instantiated dentry is legal or not. | |
194 | * VFS doesn't seem to care so check and warn here. | |
195 | */ | |
dd8ac699 | 196 | err = -EIO; |
e9be9d5e | 197 | } |
95a1c815 MS |
198 | out: |
199 | if (err) { | |
200 | dput(newdentry); | |
201 | return ERR_PTR(err); | |
202 | } | |
203 | return newdentry; | |
e9be9d5e MS |
204 | } |
205 | ||
137ec526 AG |
206 | struct dentry *ovl_create_temp(struct dentry *workdir, struct ovl_cattr *attr) |
207 | { | |
208 | return ovl_create_real(d_inode(workdir), ovl_lookup_temp(workdir), | |
209 | attr); | |
210 | } | |
211 | ||
21a22878 AG |
212 | static int ovl_set_opaque_xerr(struct dentry *dentry, struct dentry *upper, |
213 | int xerr) | |
e9be9d5e | 214 | { |
5cf5b477 MS |
215 | int err; |
216 | ||
21a22878 | 217 | err = ovl_check_setxattr(dentry, upper, OVL_XATTR_OPAQUE, "y", 1, xerr); |
5cf5b477 MS |
218 | if (!err) |
219 | ovl_dentry_set_opaque(dentry); | |
220 | ||
221 | return err; | |
e9be9d5e MS |
222 | } |
223 | ||
21a22878 AG |
224 | static int ovl_set_opaque(struct dentry *dentry, struct dentry *upperdentry) |
225 | { | |
226 | /* | |
227 | * Fail with -EIO when trying to create opaque dir and upper doesn't | |
228 | * support xattrs. ovl_rename() calls ovl_set_opaque_xerr(-EXDEV) to | |
229 | * return a specific error for noxattr case. | |
230 | */ | |
231 | return ovl_set_opaque_xerr(dentry, upperdentry, -EIO); | |
232 | } | |
233 | ||
01b39dcc AG |
234 | /* |
235 | * Common operations required to be done after creation of file on upper. | |
236 | * If @hardlink is false, then @inode is a pre-allocated inode, we may or | |
237 | * may not use to instantiate the new dentry. | |
238 | */ | |
239 | static int ovl_instantiate(struct dentry *dentry, struct inode *inode, | |
240 | struct dentry *newdentry, bool hardlink) | |
72e48481 | 241 | { |
01b39dcc AG |
242 | struct ovl_inode_params oip = { |
243 | .upperdentry = newdentry, | |
244 | .newinode = inode, | |
245 | }; | |
246 | ||
d9854c87 | 247 | ovl_dir_modified(dentry->d_parent, false); |
55acc661 | 248 | ovl_dentry_set_upper_alias(dentry); |
51f7e52d | 249 | if (!hardlink) { |
01b39dcc AG |
250 | /* |
251 | * ovl_obtain_alias() can be called after ovl_create_real() | |
252 | * and before we get here, so we may get an inode from cache | |
253 | * with the same real upperdentry that is not the inode we | |
254 | * pre-allocated. In this case we will use the cached inode | |
255 | * to instantiate the new dentry. | |
256 | * | |
257 | * XXX: if we ever use ovl_obtain_alias() to decode directory | |
258 | * file handles, need to use ovl_get_inode_locked() and | |
259 | * d_instantiate_new() here to prevent from creating two | |
260 | * hashed directory inode aliases. | |
261 | */ | |
262 | inode = ovl_get_inode(dentry->d_sb, &oip); | |
263 | if (WARN_ON(IS_ERR(inode))) | |
264 | return PTR_ERR(inode); | |
51f7e52d | 265 | } else { |
09d8b586 MS |
266 | WARN_ON(ovl_inode_real(inode) != d_inode(newdentry)); |
267 | dput(newdentry); | |
51f7e52d MS |
268 | inc_nlink(inode); |
269 | } | |
01b39dcc | 270 | |
72e48481 | 271 | d_instantiate(dentry, inode); |
01b39dcc AG |
272 | if (inode != oip.newinode) { |
273 | pr_warn_ratelimited("overlayfs: newly created inode found in cache (%pd2)\n", | |
274 | dentry); | |
275 | } | |
276 | ||
5b6c9053 AG |
277 | /* Force lookup of new upper hardlink to find its lower */ |
278 | if (hardlink) | |
279 | d_drop(dentry); | |
01b39dcc AG |
280 | |
281 | return 0; | |
72e48481 VG |
282 | } |
283 | ||
97c684cc AG |
284 | static bool ovl_type_merge(struct dentry *dentry) |
285 | { | |
286 | return OVL_TYPE_MERGE(ovl_path_type(dentry)); | |
287 | } | |
288 | ||
ee1d6d37 AG |
289 | static bool ovl_type_origin(struct dentry *dentry) |
290 | { | |
291 | return OVL_TYPE_ORIGIN(ovl_path_type(dentry)); | |
292 | } | |
293 | ||
e9be9d5e | 294 | static int ovl_create_upper(struct dentry *dentry, struct inode *inode, |
471ec5dc | 295 | struct ovl_cattr *attr) |
e9be9d5e MS |
296 | { |
297 | struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent); | |
298 | struct inode *udir = upperdir->d_inode; | |
299 | struct dentry *newdentry; | |
300 | int err; | |
301 | ||
471ec5dc | 302 | if (!attr->hardlink && !IS_POSIXACL(udir)) |
32a3d848 | 303 | attr->mode &= ~current_umask(); |
38b25697 | 304 | |
5955102c | 305 | inode_lock_nested(udir, I_MUTEX_PARENT); |
95a1c815 MS |
306 | newdentry = ovl_create_real(udir, |
307 | lookup_one_len(dentry->d_name.name, | |
308 | upperdir, | |
309 | dentry->d_name.len), | |
310 | attr); | |
e9be9d5e MS |
311 | err = PTR_ERR(newdentry); |
312 | if (IS_ERR(newdentry)) | |
313 | goto out_unlock; | |
e9be9d5e | 314 | |
4a99f3c8 | 315 | if (ovl_type_merge(dentry->d_parent) && d_is_dir(newdentry)) { |
97c684cc AG |
316 | /* Setting opaque here is just an optimization, allow to fail */ |
317 | ovl_set_opaque(dentry, newdentry); | |
318 | } | |
319 | ||
01b39dcc AG |
320 | err = ovl_instantiate(dentry, inode, newdentry, !!attr->hardlink); |
321 | if (err) | |
322 | goto out_cleanup; | |
e9be9d5e | 323 | out_unlock: |
5955102c | 324 | inode_unlock(udir); |
e9be9d5e | 325 | return err; |
01b39dcc AG |
326 | |
327 | out_cleanup: | |
328 | ovl_cleanup(udir, newdentry); | |
329 | dput(newdentry); | |
330 | goto out_unlock; | |
e9be9d5e MS |
331 | } |
332 | ||
e9be9d5e MS |
333 | static struct dentry *ovl_clear_empty(struct dentry *dentry, |
334 | struct list_head *list) | |
335 | { | |
336 | struct dentry *workdir = ovl_workdir(dentry); | |
337 | struct inode *wdir = workdir->d_inode; | |
338 | struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent); | |
339 | struct inode *udir = upperdir->d_inode; | |
340 | struct path upperpath; | |
341 | struct dentry *upper; | |
342 | struct dentry *opaquedir; | |
343 | struct kstat stat; | |
344 | int err; | |
345 | ||
cc6f67bc MS |
346 | if (WARN_ON(!workdir)) |
347 | return ERR_PTR(-EROFS); | |
348 | ||
e9be9d5e MS |
349 | err = ovl_lock_rename_workdir(workdir, upperdir); |
350 | if (err) | |
351 | goto out; | |
352 | ||
353 | ovl_path_upper(dentry, &upperpath); | |
a528d35e DH |
354 | err = vfs_getattr(&upperpath, &stat, |
355 | STATX_BASIC_STATS, AT_STATX_SYNC_AS_STAT); | |
e9be9d5e MS |
356 | if (err) |
357 | goto out_unlock; | |
358 | ||
359 | err = -ESTALE; | |
360 | if (!S_ISDIR(stat.mode)) | |
361 | goto out_unlock; | |
362 | upper = upperpath.dentry; | |
363 | if (upper->d_parent->d_inode != udir) | |
364 | goto out_unlock; | |
365 | ||
137ec526 | 366 | opaquedir = ovl_create_temp(workdir, OVL_CATTR(stat.mode)); |
e9be9d5e MS |
367 | err = PTR_ERR(opaquedir); |
368 | if (IS_ERR(opaquedir)) | |
369 | goto out_unlock; | |
370 | ||
e9be9d5e MS |
371 | err = ovl_copy_xattr(upper, opaquedir); |
372 | if (err) | |
373 | goto out_cleanup; | |
374 | ||
5cf5b477 | 375 | err = ovl_set_opaque(dentry, opaquedir); |
e9be9d5e MS |
376 | if (err) |
377 | goto out_cleanup; | |
378 | ||
5955102c | 379 | inode_lock(opaquedir->d_inode); |
e9be9d5e | 380 | err = ovl_set_attr(opaquedir, &stat); |
5955102c | 381 | inode_unlock(opaquedir->d_inode); |
e9be9d5e MS |
382 | if (err) |
383 | goto out_cleanup; | |
384 | ||
385 | err = ovl_do_rename(wdir, opaquedir, udir, upper, RENAME_EXCHANGE); | |
386 | if (err) | |
387 | goto out_cleanup; | |
388 | ||
389 | ovl_cleanup_whiteouts(upper, list); | |
390 | ovl_cleanup(wdir, upper); | |
391 | unlock_rename(workdir, upperdir); | |
392 | ||
393 | /* dentry's upper doesn't match now, get rid of it */ | |
394 | d_drop(dentry); | |
395 | ||
396 | return opaquedir; | |
397 | ||
398 | out_cleanup: | |
399 | ovl_cleanup(wdir, opaquedir); | |
e9be9d5e MS |
400 | dput(opaquedir); |
401 | out_unlock: | |
402 | unlock_rename(workdir, upperdir); | |
403 | out: | |
404 | return ERR_PTR(err); | |
405 | } | |
406 | ||
38b25697 MS |
407 | static int ovl_set_upper_acl(struct dentry *upperdentry, const char *name, |
408 | const struct posix_acl *acl) | |
409 | { | |
410 | void *buffer; | |
411 | size_t size; | |
412 | int err; | |
413 | ||
414 | if (!IS_ENABLED(CONFIG_FS_POSIX_ACL) || !acl) | |
415 | return 0; | |
416 | ||
417 | size = posix_acl_to_xattr(NULL, acl, NULL, 0); | |
418 | buffer = kmalloc(size, GFP_KERNEL); | |
419 | if (!buffer) | |
420 | return -ENOMEM; | |
421 | ||
422 | size = posix_acl_to_xattr(&init_user_ns, acl, buffer, size); | |
423 | err = size; | |
424 | if (err < 0) | |
425 | goto out_free; | |
426 | ||
427 | err = vfs_setxattr(upperdentry, name, buffer, size, XATTR_CREATE); | |
428 | out_free: | |
429 | kfree(buffer); | |
430 | return err; | |
431 | } | |
432 | ||
e9be9d5e | 433 | static int ovl_create_over_whiteout(struct dentry *dentry, struct inode *inode, |
471ec5dc | 434 | struct ovl_cattr *cattr) |
e9be9d5e MS |
435 | { |
436 | struct dentry *workdir = ovl_workdir(dentry); | |
437 | struct inode *wdir = workdir->d_inode; | |
438 | struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent); | |
439 | struct inode *udir = upperdir->d_inode; | |
440 | struct dentry *upper; | |
441 | struct dentry *newdentry; | |
442 | int err; | |
38b25697 | 443 | struct posix_acl *acl, *default_acl; |
471ec5dc | 444 | bool hardlink = !!cattr->hardlink; |
e9be9d5e | 445 | |
cc6f67bc MS |
446 | if (WARN_ON(!workdir)) |
447 | return -EROFS; | |
448 | ||
38b25697 MS |
449 | if (!hardlink) { |
450 | err = posix_acl_create(dentry->d_parent->d_inode, | |
32a3d848 | 451 | &cattr->mode, &default_acl, &acl); |
38b25697 MS |
452 | if (err) |
453 | return err; | |
454 | } | |
455 | ||
e9be9d5e MS |
456 | err = ovl_lock_rename_workdir(workdir, upperdir); |
457 | if (err) | |
458 | goto out; | |
459 | ||
e9be9d5e MS |
460 | upper = lookup_one_len(dentry->d_name.name, upperdir, |
461 | dentry->d_name.len); | |
462 | err = PTR_ERR(upper); | |
463 | if (IS_ERR(upper)) | |
95a1c815 | 464 | goto out_unlock; |
e9be9d5e | 465 | |
137ec526 | 466 | newdentry = ovl_create_temp(workdir, cattr); |
95a1c815 MS |
467 | err = PTR_ERR(newdentry); |
468 | if (IS_ERR(newdentry)) | |
469 | goto out_dput; | |
e9be9d5e | 470 | |
bb0d2b8a MS |
471 | /* |
472 | * mode could have been mutilated due to umask (e.g. sgid directory) | |
473 | */ | |
51f7e52d | 474 | if (!hardlink && |
32a3d848 AV |
475 | !S_ISLNK(cattr->mode) && |
476 | newdentry->d_inode->i_mode != cattr->mode) { | |
bb0d2b8a MS |
477 | struct iattr attr = { |
478 | .ia_valid = ATTR_MODE, | |
32a3d848 | 479 | .ia_mode = cattr->mode, |
bb0d2b8a MS |
480 | }; |
481 | inode_lock(newdentry->d_inode); | |
482 | err = notify_change(newdentry, &attr, NULL); | |
483 | inode_unlock(newdentry->d_inode); | |
484 | if (err) | |
485 | goto out_cleanup; | |
486 | } | |
38b25697 MS |
487 | if (!hardlink) { |
488 | err = ovl_set_upper_acl(newdentry, XATTR_NAME_POSIX_ACL_ACCESS, | |
489 | acl); | |
490 | if (err) | |
491 | goto out_cleanup; | |
492 | ||
493 | err = ovl_set_upper_acl(newdentry, XATTR_NAME_POSIX_ACL_DEFAULT, | |
494 | default_acl); | |
495 | if (err) | |
496 | goto out_cleanup; | |
497 | } | |
bb0d2b8a | 498 | |
32a3d848 | 499 | if (!hardlink && S_ISDIR(cattr->mode)) { |
5cf5b477 | 500 | err = ovl_set_opaque(dentry, newdentry); |
e9be9d5e MS |
501 | if (err) |
502 | goto out_cleanup; | |
503 | ||
504 | err = ovl_do_rename(wdir, newdentry, udir, upper, | |
505 | RENAME_EXCHANGE); | |
506 | if (err) | |
507 | goto out_cleanup; | |
508 | ||
509 | ovl_cleanup(wdir, upper); | |
510 | } else { | |
511 | err = ovl_do_rename(wdir, newdentry, udir, upper, 0); | |
512 | if (err) | |
513 | goto out_cleanup; | |
514 | } | |
01b39dcc AG |
515 | err = ovl_instantiate(dentry, inode, newdentry, hardlink); |
516 | if (err) | |
517 | goto out_cleanup; | |
e9be9d5e | 518 | out_dput: |
95a1c815 | 519 | dput(upper); |
e9be9d5e MS |
520 | out_unlock: |
521 | unlock_rename(workdir, upperdir); | |
522 | out: | |
38b25697 MS |
523 | if (!hardlink) { |
524 | posix_acl_release(acl); | |
525 | posix_acl_release(default_acl); | |
526 | } | |
e9be9d5e MS |
527 | return err; |
528 | ||
529 | out_cleanup: | |
530 | ovl_cleanup(wdir, newdentry); | |
95a1c815 MS |
531 | dput(newdentry); |
532 | goto out_dput; | |
e9be9d5e MS |
533 | } |
534 | ||
51f7e52d | 535 | static int ovl_create_or_link(struct dentry *dentry, struct inode *inode, |
471ec5dc | 536 | struct ovl_cattr *attr, bool origin) |
e9be9d5e MS |
537 | { |
538 | int err; | |
1175b6b8 VG |
539 | const struct cred *old_cred; |
540 | struct cred *override_cred; | |
ea3dad18 | 541 | struct dentry *parent = dentry->d_parent; |
e9be9d5e | 542 | |
ea3dad18 | 543 | err = ovl_copy_up(parent); |
e9be9d5e | 544 | if (err) |
51f7e52d | 545 | return err; |
bb0d2b8a | 546 | |
1175b6b8 | 547 | old_cred = ovl_override_creds(dentry->d_sb); |
ea3dad18 AG |
548 | |
549 | /* | |
550 | * When linking a file with copy up origin into a new parent, mark the | |
551 | * new parent dir "impure". | |
552 | */ | |
553 | if (origin) { | |
554 | err = ovl_set_impure(parent, ovl_dentry_upper(parent)); | |
555 | if (err) | |
556 | goto out_revert_creds; | |
557 | } | |
558 | ||
1175b6b8 VG |
559 | err = -ENOMEM; |
560 | override_cred = prepare_creds(); | |
561 | if (override_cred) { | |
bb0d2b8a MS |
562 | override_cred->fsuid = inode->i_uid; |
563 | override_cred->fsgid = inode->i_gid; | |
471ec5dc | 564 | if (!attr->hardlink) { |
2602625b | 565 | err = security_dentry_create_files_as(dentry, |
32a3d848 | 566 | attr->mode, &dentry->d_name, old_cred, |
2602625b VG |
567 | override_cred); |
568 | if (err) { | |
569 | put_cred(override_cred); | |
570 | goto out_revert_creds; | |
571 | } | |
572 | } | |
1175b6b8 VG |
573 | put_cred(override_creds(override_cred)); |
574 | put_cred(override_cred); | |
575 | ||
c412ce49 | 576 | if (!ovl_dentry_is_whiteout(dentry)) |
471ec5dc | 577 | err = ovl_create_upper(dentry, inode, attr); |
1175b6b8 | 578 | else |
471ec5dc | 579 | err = ovl_create_over_whiteout(dentry, inode, attr); |
e9be9d5e | 580 | } |
2602625b | 581 | out_revert_creds: |
1175b6b8 | 582 | revert_creds(old_cred); |
e9be9d5e MS |
583 | return err; |
584 | } | |
585 | ||
586 | static int ovl_create_object(struct dentry *dentry, int mode, dev_t rdev, | |
587 | const char *link) | |
588 | { | |
589 | int err; | |
51f7e52d | 590 | struct inode *inode; |
471ec5dc | 591 | struct ovl_cattr attr = { |
51f7e52d | 592 | .rdev = rdev, |
32a3d848 | 593 | .link = link, |
51f7e52d | 594 | }; |
e9be9d5e MS |
595 | |
596 | err = ovl_want_write(dentry); | |
51f7e52d MS |
597 | if (err) |
598 | goto out; | |
599 | ||
01b39dcc | 600 | /* Preallocate inode to be used by ovl_get_inode() */ |
51f7e52d | 601 | err = -ENOMEM; |
ca4c8a3a | 602 | inode = ovl_new_inode(dentry->d_sb, mode, rdev); |
51f7e52d MS |
603 | if (!inode) |
604 | goto out_drop_write; | |
605 | ||
6faf05c2 MS |
606 | spin_lock(&inode->i_lock); |
607 | inode->i_state |= I_CREATING; | |
608 | spin_unlock(&inode->i_lock); | |
609 | ||
51f7e52d | 610 | inode_init_owner(inode, dentry->d_parent->d_inode, mode); |
32a3d848 | 611 | attr.mode = inode->i_mode; |
51f7e52d | 612 | |
471ec5dc | 613 | err = ovl_create_or_link(dentry, inode, &attr, false); |
01b39dcc AG |
614 | /* Did we end up using the preallocated inode? */ |
615 | if (inode != d_inode(dentry)) | |
51f7e52d | 616 | iput(inode); |
e9be9d5e | 617 | |
51f7e52d MS |
618 | out_drop_write: |
619 | ovl_drop_write(dentry); | |
620 | out: | |
e9be9d5e MS |
621 | return err; |
622 | } | |
623 | ||
624 | static int ovl_create(struct inode *dir, struct dentry *dentry, umode_t mode, | |
625 | bool excl) | |
626 | { | |
627 | return ovl_create_object(dentry, (mode & 07777) | S_IFREG, 0, NULL); | |
628 | } | |
629 | ||
630 | static int ovl_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) | |
631 | { | |
632 | return ovl_create_object(dentry, (mode & 07777) | S_IFDIR, 0, NULL); | |
633 | } | |
634 | ||
635 | static int ovl_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, | |
636 | dev_t rdev) | |
637 | { | |
638 | /* Don't allow creation of "whiteout" on overlay */ | |
639 | if (S_ISCHR(mode) && rdev == WHITEOUT_DEV) | |
640 | return -EPERM; | |
641 | ||
642 | return ovl_create_object(dentry, mode, rdev, NULL); | |
643 | } | |
644 | ||
645 | static int ovl_symlink(struct inode *dir, struct dentry *dentry, | |
646 | const char *link) | |
647 | { | |
648 | return ovl_create_object(dentry, S_IFLNK, 0, link); | |
649 | } | |
650 | ||
651 | static int ovl_link(struct dentry *old, struct inode *newdir, | |
652 | struct dentry *new) | |
653 | { | |
654 | int err; | |
5f8415d6 | 655 | bool locked = false; |
51f7e52d | 656 | struct inode *inode; |
e9be9d5e MS |
657 | |
658 | err = ovl_want_write(old); | |
659 | if (err) | |
660 | goto out; | |
661 | ||
662 | err = ovl_copy_up(old); | |
663 | if (err) | |
664 | goto out_drop_write; | |
665 | ||
6cd07870 AG |
666 | err = ovl_copy_up(new->d_parent); |
667 | if (err) | |
668 | goto out_drop_write; | |
669 | ||
4120fe64 VG |
670 | if (ovl_is_metacopy_dentry(old)) { |
671 | err = ovl_set_redirect(old, false); | |
672 | if (err) | |
673 | goto out_drop_write; | |
674 | } | |
675 | ||
5f8415d6 AG |
676 | err = ovl_nlink_start(old, &locked); |
677 | if (err) | |
678 | goto out_drop_write; | |
679 | ||
51f7e52d MS |
680 | inode = d_inode(old); |
681 | ihold(inode); | |
682 | ||
471ec5dc AG |
683 | err = ovl_create_or_link(new, inode, |
684 | &(struct ovl_cattr) {.hardlink = ovl_dentry_upper(old)}, | |
685 | ovl_type_origin(old)); | |
51f7e52d MS |
686 | if (err) |
687 | iput(inode); | |
e9be9d5e | 688 | |
5f8415d6 | 689 | ovl_nlink_end(old, locked); |
e9be9d5e MS |
690 | out_drop_write: |
691 | ovl_drop_write(old); | |
692 | out: | |
693 | return err; | |
694 | } | |
695 | ||
9020df37 MS |
696 | static bool ovl_matches_upper(struct dentry *dentry, struct dentry *upper) |
697 | { | |
698 | return d_inode(ovl_dentry_upper(dentry)) == d_inode(upper); | |
699 | } | |
700 | ||
6d0a8a90 AG |
701 | static int ovl_remove_and_whiteout(struct dentry *dentry, |
702 | struct list_head *list) | |
e9be9d5e MS |
703 | { |
704 | struct dentry *workdir = ovl_workdir(dentry); | |
e9be9d5e | 705 | struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent); |
e9be9d5e MS |
706 | struct dentry *upper; |
707 | struct dentry *opaquedir = NULL; | |
708 | int err; | |
709 | ||
cc6f67bc MS |
710 | if (WARN_ON(!workdir)) |
711 | return -EROFS; | |
712 | ||
6d0a8a90 AG |
713 | if (!list_empty(list)) { |
714 | opaquedir = ovl_clear_empty(dentry, list); | |
30c17ebf MS |
715 | err = PTR_ERR(opaquedir); |
716 | if (IS_ERR(opaquedir)) | |
717 | goto out; | |
e9be9d5e MS |
718 | } |
719 | ||
720 | err = ovl_lock_rename_workdir(workdir, upperdir); | |
721 | if (err) | |
722 | goto out_dput; | |
723 | ||
cfc9fde0 MP |
724 | upper = lookup_one_len(dentry->d_name.name, upperdir, |
725 | dentry->d_name.len); | |
726 | err = PTR_ERR(upper); | |
727 | if (IS_ERR(upper)) | |
e9be9d5e MS |
728 | goto out_unlock; |
729 | ||
cfc9fde0 MP |
730 | err = -ESTALE; |
731 | if ((opaquedir && upper != opaquedir) || | |
732 | (!opaquedir && ovl_dentry_upper(dentry) && | |
9020df37 | 733 | !ovl_matches_upper(dentry, upper))) { |
cfc9fde0 MP |
734 | goto out_dput_upper; |
735 | } | |
e9be9d5e | 736 | |
e7dd0e71 | 737 | err = ovl_cleanup_and_whiteout(workdir, d_inode(upperdir), upper); |
cfc9fde0 | 738 | if (err) |
e7dd0e71 | 739 | goto out_d_drop; |
e9be9d5e | 740 | |
d9854c87 | 741 | ovl_dir_modified(dentry->d_parent, true); |
e9be9d5e MS |
742 | out_d_drop: |
743 | d_drop(dentry); | |
cfc9fde0 MP |
744 | out_dput_upper: |
745 | dput(upper); | |
e9be9d5e MS |
746 | out_unlock: |
747 | unlock_rename(workdir, upperdir); | |
748 | out_dput: | |
749 | dput(opaquedir); | |
750 | out: | |
751 | return err; | |
e9be9d5e MS |
752 | } |
753 | ||
6d0a8a90 AG |
754 | static int ovl_remove_upper(struct dentry *dentry, bool is_dir, |
755 | struct list_head *list) | |
e9be9d5e MS |
756 | { |
757 | struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent); | |
758 | struct inode *dir = upperdir->d_inode; | |
11f37104 | 759 | struct dentry *upper; |
d1595119 | 760 | struct dentry *opaquedir = NULL; |
e9be9d5e MS |
761 | int err; |
762 | ||
6d0a8a90 AG |
763 | if (!list_empty(list)) { |
764 | opaquedir = ovl_clear_empty(dentry, list); | |
d1595119 AG |
765 | err = PTR_ERR(opaquedir); |
766 | if (IS_ERR(opaquedir)) | |
767 | goto out; | |
768 | } | |
769 | ||
5955102c | 770 | inode_lock_nested(dir, I_MUTEX_PARENT); |
11f37104 MS |
771 | upper = lookup_one_len(dentry->d_name.name, upperdir, |
772 | dentry->d_name.len); | |
773 | err = PTR_ERR(upper); | |
774 | if (IS_ERR(upper)) | |
775 | goto out_unlock; | |
776 | ||
e9be9d5e | 777 | err = -ESTALE; |
d1595119 | 778 | if ((opaquedir && upper != opaquedir) || |
9020df37 | 779 | (!opaquedir && !ovl_matches_upper(dentry, upper))) |
d1595119 AG |
780 | goto out_dput_upper; |
781 | ||
782 | if (is_dir) | |
783 | err = vfs_rmdir(dir, upper); | |
784 | else | |
785 | err = vfs_unlink(dir, upper, NULL); | |
d9854c87 | 786 | ovl_dir_modified(dentry->d_parent, ovl_type_origin(dentry)); |
e9be9d5e MS |
787 | |
788 | /* | |
789 | * Keeping this dentry hashed would mean having to release | |
790 | * upperpath/lowerpath, which could only be done if we are the | |
791 | * sole user of this dentry. Too tricky... Just unhash for | |
792 | * now. | |
793 | */ | |
ce9113bb RW |
794 | if (!err) |
795 | d_drop(dentry); | |
d1595119 AG |
796 | out_dput_upper: |
797 | dput(upper); | |
11f37104 | 798 | out_unlock: |
5955102c | 799 | inode_unlock(dir); |
d1595119 AG |
800 | dput(opaquedir); |
801 | out: | |
e9be9d5e MS |
802 | return err; |
803 | } | |
804 | ||
6d0a8a90 AG |
805 | static bool ovl_pure_upper(struct dentry *dentry) |
806 | { | |
807 | return !ovl_dentry_lower(dentry) && | |
808 | !ovl_test_flag(OVL_WHITEOUTS, d_inode(dentry)); | |
809 | } | |
810 | ||
e9be9d5e MS |
811 | static int ovl_do_remove(struct dentry *dentry, bool is_dir) |
812 | { | |
e9be9d5e | 813 | int err; |
5f8415d6 | 814 | bool locked = false; |
1175b6b8 | 815 | const struct cred *old_cred; |
d9854c87 | 816 | struct dentry *upperdentry; |
6d0a8a90 AG |
817 | bool lower_positive = ovl_lower_positive(dentry); |
818 | LIST_HEAD(list); | |
819 | ||
820 | /* No need to clean pure upper removed by vfs_rmdir() */ | |
821 | if (is_dir && (lower_positive || !ovl_pure_upper(dentry))) { | |
822 | err = ovl_check_empty_dir(dentry, &list); | |
823 | if (err) | |
824 | goto out; | |
825 | } | |
1175b6b8 | 826 | |
e9be9d5e MS |
827 | err = ovl_want_write(dentry); |
828 | if (err) | |
829 | goto out; | |
830 | ||
831 | err = ovl_copy_up(dentry->d_parent); | |
832 | if (err) | |
833 | goto out_drop_write; | |
834 | ||
5f8415d6 AG |
835 | err = ovl_nlink_start(dentry, &locked); |
836 | if (err) | |
837 | goto out_drop_write; | |
e9be9d5e | 838 | |
1175b6b8 | 839 | old_cred = ovl_override_creds(dentry->d_sb); |
6d0a8a90 AG |
840 | if (!lower_positive) |
841 | err = ovl_remove_upper(dentry, is_dir, &list); | |
1175b6b8 | 842 | else |
6d0a8a90 | 843 | err = ovl_remove_and_whiteout(dentry, &list); |
1175b6b8 | 844 | revert_creds(old_cred); |
dbc816d0 MS |
845 | if (!err) { |
846 | if (is_dir) | |
847 | clear_nlink(dentry->d_inode); | |
848 | else | |
849 | drop_nlink(dentry->d_inode); | |
850 | } | |
5f8415d6 | 851 | ovl_nlink_end(dentry, locked); |
d9854c87 MS |
852 | |
853 | /* | |
854 | * Copy ctime | |
855 | * | |
856 | * Note: we fail to update ctime if there was no copy-up, only a | |
857 | * whiteout | |
858 | */ | |
859 | upperdentry = ovl_dentry_upper(dentry); | |
860 | if (upperdentry) | |
861 | ovl_copyattr(d_inode(upperdentry), d_inode(dentry)); | |
862 | ||
e9be9d5e MS |
863 | out_drop_write: |
864 | ovl_drop_write(dentry); | |
865 | out: | |
6d0a8a90 | 866 | ovl_cache_free(&list); |
e9be9d5e MS |
867 | return err; |
868 | } | |
869 | ||
870 | static int ovl_unlink(struct inode *dir, struct dentry *dentry) | |
871 | { | |
872 | return ovl_do_remove(dentry, false); | |
873 | } | |
874 | ||
875 | static int ovl_rmdir(struct inode *dir, struct dentry *dentry) | |
876 | { | |
877 | return ovl_do_remove(dentry, true); | |
878 | } | |
879 | ||
370e55ac MS |
880 | static bool ovl_type_merge_or_lower(struct dentry *dentry) |
881 | { | |
882 | enum ovl_path_type type = ovl_path_type(dentry); | |
883 | ||
884 | return OVL_TYPE_MERGE(type) || !OVL_TYPE_UPPER(type); | |
885 | } | |
886 | ||
a6c60655 MS |
887 | static bool ovl_can_move(struct dentry *dentry) |
888 | { | |
889 | return ovl_redirect_dir(dentry->d_sb) || | |
890 | !d_is_dir(dentry) || !ovl_type_merge_or_lower(dentry); | |
891 | } | |
892 | ||
7bb08383 | 893 | static char *ovl_get_redirect(struct dentry *dentry, bool abs_redirect) |
a6c60655 MS |
894 | { |
895 | char *buf, *ret; | |
896 | struct dentry *d, *tmp; | |
3ea22a71 | 897 | int buflen = ovl_redirect_max + 1; |
a6c60655 | 898 | |
7bb08383 | 899 | if (!abs_redirect) { |
a6c60655 MS |
900 | ret = kstrndup(dentry->d_name.name, dentry->d_name.len, |
901 | GFP_KERNEL); | |
902 | goto out; | |
903 | } | |
904 | ||
0ee931c4 | 905 | buf = ret = kmalloc(buflen, GFP_KERNEL); |
a6c60655 MS |
906 | if (!buf) |
907 | goto out; | |
908 | ||
909 | buflen--; | |
910 | buf[buflen] = '\0'; | |
911 | for (d = dget(dentry); !IS_ROOT(d);) { | |
912 | const char *name; | |
913 | int thislen; | |
914 | ||
915 | spin_lock(&d->d_lock); | |
916 | name = ovl_dentry_get_redirect(d); | |
917 | if (name) { | |
918 | thislen = strlen(name); | |
919 | } else { | |
920 | name = d->d_name.name; | |
921 | thislen = d->d_name.len; | |
922 | } | |
923 | ||
924 | /* If path is too long, fall back to userspace move */ | |
925 | if (thislen + (name[0] != '/') > buflen) { | |
926 | ret = ERR_PTR(-EXDEV); | |
927 | spin_unlock(&d->d_lock); | |
928 | goto out_put; | |
929 | } | |
930 | ||
931 | buflen -= thislen; | |
932 | memcpy(&buf[buflen], name, thislen); | |
933 | tmp = dget_dlock(d->d_parent); | |
934 | spin_unlock(&d->d_lock); | |
935 | ||
936 | dput(d); | |
937 | d = tmp; | |
938 | ||
939 | /* Absolute redirect: finished */ | |
940 | if (buf[buflen] == '/') | |
941 | break; | |
942 | buflen--; | |
943 | buf[buflen] = '/'; | |
944 | } | |
945 | ret = kstrdup(&buf[buflen], GFP_KERNEL); | |
946 | out_put: | |
947 | dput(d); | |
948 | kfree(buf); | |
949 | out: | |
950 | return ret ? ret : ERR_PTR(-ENOMEM); | |
951 | } | |
952 | ||
7bb08383 VG |
953 | static bool ovl_need_absolute_redirect(struct dentry *dentry, bool samedir) |
954 | { | |
955 | struct dentry *lowerdentry; | |
956 | ||
957 | if (!samedir) | |
958 | return true; | |
959 | ||
960 | if (d_is_dir(dentry)) | |
961 | return false; | |
962 | ||
963 | /* | |
964 | * For non-dir hardlinked files, we need absolute redirects | |
965 | * in general as two upper hardlinks could be in different | |
966 | * dirs. We could put a relative redirect now and convert | |
967 | * it to absolute redirect later. But when nlink > 1 and | |
968 | * indexing is on, that means relative redirect needs to be | |
969 | * converted to absolute during copy up of another lower | |
970 | * hardllink as well. | |
971 | * | |
972 | * So without optimizing too much, just check if lower is | |
973 | * a hard link or not. If lower is hard link, put absolute | |
974 | * redirect. | |
975 | */ | |
976 | lowerdentry = ovl_dentry_lower(dentry); | |
977 | return (d_inode(lowerdentry)->i_nlink > 1); | |
978 | } | |
979 | ||
a6c60655 MS |
980 | static int ovl_set_redirect(struct dentry *dentry, bool samedir) |
981 | { | |
982 | int err; | |
983 | const char *redirect = ovl_dentry_get_redirect(dentry); | |
7bb08383 | 984 | bool absolute_redirect = ovl_need_absolute_redirect(dentry, samedir); |
a6c60655 | 985 | |
7bb08383 | 986 | if (redirect && (!absolute_redirect || redirect[0] == '/')) |
a6c60655 MS |
987 | return 0; |
988 | ||
7bb08383 | 989 | redirect = ovl_get_redirect(dentry, absolute_redirect); |
a6c60655 MS |
990 | if (IS_ERR(redirect)) |
991 | return PTR_ERR(redirect); | |
992 | ||
21a22878 AG |
993 | err = ovl_check_setxattr(dentry, ovl_dentry_upper(dentry), |
994 | OVL_XATTR_REDIRECT, | |
995 | redirect, strlen(redirect), -EXDEV); | |
a6c60655 MS |
996 | if (!err) { |
997 | spin_lock(&dentry->d_lock); | |
998 | ovl_dentry_set_redirect(dentry, redirect); | |
999 | spin_unlock(&dentry->d_lock); | |
1000 | } else { | |
1001 | kfree(redirect); | |
da2e6b7e AG |
1002 | pr_warn_ratelimited("overlayfs: failed to set redirect (%i)\n", |
1003 | err); | |
a6c60655 MS |
1004 | /* Fall back to userspace copy-up */ |
1005 | err = -EXDEV; | |
1006 | } | |
1007 | return err; | |
1008 | } | |
1009 | ||
6c02cb59 MS |
1010 | static int ovl_rename(struct inode *olddir, struct dentry *old, |
1011 | struct inode *newdir, struct dentry *new, | |
1012 | unsigned int flags) | |
e9be9d5e MS |
1013 | { |
1014 | int err; | |
5f8415d6 | 1015 | bool locked = false; |
e9be9d5e MS |
1016 | struct dentry *old_upperdir; |
1017 | struct dentry *new_upperdir; | |
1018 | struct dentry *olddentry; | |
1019 | struct dentry *newdentry; | |
1020 | struct dentry *trap; | |
1021 | bool old_opaque; | |
1022 | bool new_opaque; | |
e9be9d5e MS |
1023 | bool cleanup_whiteout = false; |
1024 | bool overwrite = !(flags & RENAME_EXCHANGE); | |
e36cb0b8 | 1025 | bool is_dir = d_is_dir(old); |
370e55ac | 1026 | bool new_is_dir = d_is_dir(new); |
a6c60655 | 1027 | bool samedir = olddir == newdir; |
e9be9d5e MS |
1028 | struct dentry *opaquedir = NULL; |
1029 | const struct cred *old_cred = NULL; | |
6d0a8a90 | 1030 | LIST_HEAD(list); |
e9be9d5e MS |
1031 | |
1032 | err = -EINVAL; | |
1033 | if (flags & ~(RENAME_EXCHANGE | RENAME_NOREPLACE)) | |
1034 | goto out; | |
1035 | ||
1036 | flags &= ~RENAME_NOREPLACE; | |
1037 | ||
e9be9d5e | 1038 | /* Don't copy up directory trees */ |
e9be9d5e | 1039 | err = -EXDEV; |
a6c60655 | 1040 | if (!ovl_can_move(old)) |
370e55ac | 1041 | goto out; |
a6c60655 | 1042 | if (!overwrite && !ovl_can_move(new)) |
e9be9d5e | 1043 | goto out; |
e9be9d5e | 1044 | |
6d0a8a90 AG |
1045 | if (overwrite && new_is_dir && !ovl_pure_upper(new)) { |
1046 | err = ovl_check_empty_dir(new, &list); | |
1047 | if (err) | |
1048 | goto out; | |
1049 | } | |
1050 | ||
1051 | if (overwrite) { | |
1052 | if (ovl_lower_positive(old)) { | |
1053 | if (!ovl_dentry_is_whiteout(new)) { | |
1054 | /* Whiteout source */ | |
1055 | flags |= RENAME_WHITEOUT; | |
1056 | } else { | |
1057 | /* Switch whiteouts */ | |
1058 | flags |= RENAME_EXCHANGE; | |
1059 | } | |
1060 | } else if (is_dir && ovl_dentry_is_whiteout(new)) { | |
1061 | flags |= RENAME_EXCHANGE; | |
1062 | cleanup_whiteout = true; | |
1063 | } | |
1064 | } | |
1065 | ||
e9be9d5e MS |
1066 | err = ovl_want_write(old); |
1067 | if (err) | |
1068 | goto out; | |
1069 | ||
1070 | err = ovl_copy_up(old); | |
1071 | if (err) | |
1072 | goto out_drop_write; | |
1073 | ||
1074 | err = ovl_copy_up(new->d_parent); | |
1075 | if (err) | |
1076 | goto out_drop_write; | |
1077 | if (!overwrite) { | |
1078 | err = ovl_copy_up(new); | |
1079 | if (err) | |
1080 | goto out_drop_write; | |
5f8415d6 AG |
1081 | } else { |
1082 | err = ovl_nlink_start(new, &locked); | |
1083 | if (err) | |
1084 | goto out_drop_write; | |
e9be9d5e MS |
1085 | } |
1086 | ||
1175b6b8 | 1087 | old_cred = ovl_override_creds(old->d_sb); |
e9be9d5e | 1088 | |
6d0a8a90 AG |
1089 | if (!list_empty(&list)) { |
1090 | opaquedir = ovl_clear_empty(new, &list); | |
e9be9d5e MS |
1091 | err = PTR_ERR(opaquedir); |
1092 | if (IS_ERR(opaquedir)) { | |
1093 | opaquedir = NULL; | |
1094 | goto out_revert_creds; | |
1095 | } | |
1096 | } | |
1097 | ||
e9be9d5e MS |
1098 | old_upperdir = ovl_dentry_upper(old->d_parent); |
1099 | new_upperdir = ovl_dentry_upper(new->d_parent); | |
1100 | ||
ee1d6d37 AG |
1101 | if (!samedir) { |
1102 | /* | |
1103 | * When moving a merge dir or non-dir with copy up origin into | |
f3a15685 AG |
1104 | * a new parent, we are marking the new parent dir "impure". |
1105 | * When ovl_iterate() iterates an "impure" upper dir, it will | |
1106 | * lookup the origin inodes of the entries to fill d_ino. | |
ee1d6d37 | 1107 | */ |
f3a15685 | 1108 | if (ovl_type_origin(old)) { |
ee1d6d37 AG |
1109 | err = ovl_set_impure(new->d_parent, new_upperdir); |
1110 | if (err) | |
1111 | goto out_revert_creds; | |
1112 | } | |
f3a15685 | 1113 | if (!overwrite && ovl_type_origin(new)) { |
ee1d6d37 AG |
1114 | err = ovl_set_impure(old->d_parent, old_upperdir); |
1115 | if (err) | |
1116 | goto out_revert_creds; | |
1117 | } | |
1118 | } | |
1119 | ||
e9be9d5e MS |
1120 | trap = lock_rename(new_upperdir, old_upperdir); |
1121 | ||
11f37104 MS |
1122 | olddentry = lookup_one_len(old->d_name.name, old_upperdir, |
1123 | old->d_name.len); | |
1124 | err = PTR_ERR(olddentry); | |
1125 | if (IS_ERR(olddentry)) | |
1126 | goto out_unlock; | |
1127 | ||
1128 | err = -ESTALE; | |
9020df37 | 1129 | if (!ovl_matches_upper(old, olddentry)) |
11f37104 MS |
1130 | goto out_dput_old; |
1131 | ||
1132 | newdentry = lookup_one_len(new->d_name.name, new_upperdir, | |
1133 | new->d_name.len); | |
1134 | err = PTR_ERR(newdentry); | |
1135 | if (IS_ERR(newdentry)) | |
1136 | goto out_dput_old; | |
1137 | ||
3ee23ff1 MS |
1138 | old_opaque = ovl_dentry_is_opaque(old); |
1139 | new_opaque = ovl_dentry_is_opaque(new); | |
1140 | ||
11f37104 | 1141 | err = -ESTALE; |
09d8b586 | 1142 | if (d_inode(new) && ovl_dentry_upper(new)) { |
e9be9d5e | 1143 | if (opaquedir) { |
11f37104 MS |
1144 | if (newdentry != opaquedir) |
1145 | goto out_dput; | |
e9be9d5e | 1146 | } else { |
9020df37 | 1147 | if (!ovl_matches_upper(new, newdentry)) |
11f37104 | 1148 | goto out_dput; |
e9be9d5e MS |
1149 | } |
1150 | } else { | |
11f37104 MS |
1151 | if (!d_is_negative(newdentry) && |
1152 | (!new_opaque || !ovl_is_whiteout(newdentry))) | |
1153 | goto out_dput; | |
e9be9d5e MS |
1154 | } |
1155 | ||
e9be9d5e MS |
1156 | if (olddentry == trap) |
1157 | goto out_dput; | |
1158 | if (newdentry == trap) | |
1159 | goto out_dput; | |
1160 | ||
804032fa MS |
1161 | if (WARN_ON(olddentry->d_inode == newdentry->d_inode)) |
1162 | goto out_dput; | |
1163 | ||
5cf5b477 | 1164 | err = 0; |
7bb08383 VG |
1165 | if (ovl_type_merge_or_lower(old)) |
1166 | err = ovl_set_redirect(old, samedir); | |
1167 | else if (is_dir && !old_opaque && ovl_type_merge(new->d_parent)) | |
1168 | err = ovl_set_opaque_xerr(old, olddentry, -EXDEV); | |
1169 | if (err) | |
1170 | goto out_dput; | |
1171 | ||
1172 | if (!overwrite && ovl_type_merge_or_lower(new)) | |
1173 | err = ovl_set_redirect(new, samedir); | |
1174 | else if (!overwrite && new_is_dir && !new_opaque && | |
1175 | ovl_type_merge(old->d_parent)) | |
1176 | err = ovl_set_opaque_xerr(new, newdentry, -EXDEV); | |
1177 | if (err) | |
1178 | goto out_dput; | |
e9be9d5e | 1179 | |
3ee23ff1 MS |
1180 | err = ovl_do_rename(old_upperdir->d_inode, olddentry, |
1181 | new_upperdir->d_inode, newdentry, flags); | |
1182 | if (err) | |
e9be9d5e | 1183 | goto out_dput; |
e9be9d5e MS |
1184 | |
1185 | if (cleanup_whiteout) | |
1186 | ovl_cleanup(old_upperdir->d_inode, newdentry); | |
1187 | ||
f681eb1d AG |
1188 | if (overwrite && d_inode(new)) { |
1189 | if (new_is_dir) | |
1190 | clear_nlink(d_inode(new)); | |
1191 | else | |
1192 | drop_nlink(d_inode(new)); | |
1193 | } | |
1194 | ||
d9854c87 MS |
1195 | ovl_dir_modified(old->d_parent, ovl_type_origin(old) || |
1196 | (!overwrite && ovl_type_origin(new))); | |
1197 | ovl_dir_modified(new->d_parent, ovl_type_origin(old) || | |
1198 | (d_inode(new) && ovl_type_origin(new))); | |
1199 | ||
1200 | /* copy ctime: */ | |
1201 | ovl_copyattr(d_inode(olddentry), d_inode(old)); | |
1202 | if (d_inode(new) && ovl_dentry_upper(new)) | |
1203 | ovl_copyattr(d_inode(newdentry), d_inode(new)); | |
e9be9d5e MS |
1204 | |
1205 | out_dput: | |
1206 | dput(newdentry); | |
11f37104 MS |
1207 | out_dput_old: |
1208 | dput(olddentry); | |
e9be9d5e MS |
1209 | out_unlock: |
1210 | unlock_rename(new_upperdir, old_upperdir); | |
1211 | out_revert_creds: | |
1175b6b8 | 1212 | revert_creds(old_cred); |
5f8415d6 | 1213 | ovl_nlink_end(new, locked); |
e9be9d5e MS |
1214 | out_drop_write: |
1215 | ovl_drop_write(old); | |
1216 | out: | |
1217 | dput(opaquedir); | |
6d0a8a90 | 1218 | ovl_cache_free(&list); |
e9be9d5e MS |
1219 | return err; |
1220 | } | |
1221 | ||
1222 | const struct inode_operations ovl_dir_inode_operations = { | |
1223 | .lookup = ovl_lookup, | |
1224 | .mkdir = ovl_mkdir, | |
1225 | .symlink = ovl_symlink, | |
1226 | .unlink = ovl_unlink, | |
1227 | .rmdir = ovl_rmdir, | |
6c02cb59 | 1228 | .rename = ovl_rename, |
e9be9d5e MS |
1229 | .link = ovl_link, |
1230 | .setattr = ovl_setattr, | |
1231 | .create = ovl_create, | |
1232 | .mknod = ovl_mknod, | |
1233 | .permission = ovl_permission, | |
5b712091 | 1234 | .getattr = ovl_getattr, |
e9be9d5e | 1235 | .listxattr = ovl_listxattr, |
39a25b2b | 1236 | .get_acl = ovl_get_acl, |
d719e8f2 | 1237 | .update_time = ovl_update_time, |
e9be9d5e | 1238 | }; |