Commit | Line | Data |
---|---|---|
d2912cb1 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
e9be9d5e MS |
2 | /* |
3 | * | |
4 | * Copyright (C) 2011 Novell Inc. | |
e9be9d5e MS |
5 | */ |
6 | ||
7 | #include <linux/fs.h> | |
8 | #include <linux/namei.h> | |
9 | #include <linux/xattr.h> | |
10 | #include <linux/security.h> | |
11 | #include <linux/cred.h> | |
3ea22a71 | 12 | #include <linux/module.h> |
38b25697 MS |
13 | #include <linux/posix_acl.h> |
14 | #include <linux/posix_acl_xattr.h> | |
6a45b362 | 15 | #include <linux/atomic.h> |
a6c60655 | 16 | #include <linux/ratelimit.h> |
e9be9d5e MS |
17 | #include "overlayfs.h" |
18 | ||
3ea22a71 MS |
19 | static unsigned short ovl_redirect_max = 256; |
20 | module_param_named(redirect_max, ovl_redirect_max, ushort, 0644); | |
253e7483 | 21 | MODULE_PARM_DESC(redirect_max, |
3ea22a71 MS |
22 | "Maximum length of absolute redirect xattr value"); |
23 | ||
4120fe64 VG |
24 | static int ovl_set_redirect(struct dentry *dentry, bool samedir); |
25 | ||
415543d5 | 26 | int ovl_cleanup(struct inode *wdir, struct dentry *wdentry) |
e9be9d5e MS |
27 | { |
28 | int err; | |
29 | ||
30 | dget(wdentry); | |
e36cb0b8 | 31 | if (d_is_dir(wdentry)) |
e9be9d5e MS |
32 | err = ovl_do_rmdir(wdir, wdentry); |
33 | else | |
34 | err = ovl_do_unlink(wdir, wdentry); | |
35 | dput(wdentry); | |
36 | ||
37 | if (err) { | |
38 | pr_err("overlayfs: cleanup of '%pd2' failed (%i)\n", | |
39 | wdentry, err); | |
40 | } | |
415543d5 AG |
41 | |
42 | return err; | |
e9be9d5e MS |
43 | } |
44 | ||
137ec526 | 45 | static struct dentry *ovl_lookup_temp(struct dentry *workdir) |
e9be9d5e MS |
46 | { |
47 | struct dentry *temp; | |
48 | char name[20]; | |
6a45b362 | 49 | static atomic_t temp_id = ATOMIC_INIT(0); |
e9be9d5e | 50 | |
6a45b362 RW |
51 | /* counter is allowed to wrap, since temp dentries are ephemeral */ |
52 | snprintf(name, sizeof(name), "#%x", atomic_inc_return(&temp_id)); | |
e9be9d5e MS |
53 | |
54 | temp = lookup_one_len(name, workdir, strlen(name)); | |
55 | if (!IS_ERR(temp) && temp->d_inode) { | |
56 | pr_err("overlayfs: workdir/%s already exists\n", name); | |
57 | dput(temp); | |
58 | temp = ERR_PTR(-EIO); | |
59 | } | |
60 | ||
61 | return temp; | |
62 | } | |
63 | ||
64 | /* caller holds i_mutex on workdir */ | |
e7dd0e71 | 65 | static struct dentry *ovl_whiteout(struct dentry *workdir) |
e9be9d5e MS |
66 | { |
67 | int err; | |
68 | struct dentry *whiteout; | |
69 | struct inode *wdir = workdir->d_inode; | |
70 | ||
3d27573c | 71 | whiteout = ovl_lookup_temp(workdir); |
e9be9d5e MS |
72 | if (IS_ERR(whiteout)) |
73 | return whiteout; | |
74 | ||
75 | err = ovl_do_whiteout(wdir, whiteout); | |
76 | if (err) { | |
77 | dput(whiteout); | |
78 | whiteout = ERR_PTR(err); | |
79 | } | |
80 | ||
81 | return whiteout; | |
82 | } | |
83 | ||
e7dd0e71 AG |
84 | /* Caller must hold i_mutex on both workdir and dir */ |
85 | int ovl_cleanup_and_whiteout(struct dentry *workdir, struct inode *dir, | |
86 | struct dentry *dentry) | |
87 | { | |
88 | struct inode *wdir = workdir->d_inode; | |
89 | struct dentry *whiteout; | |
90 | int err; | |
91 | int flags = 0; | |
92 | ||
93 | whiteout = ovl_whiteout(workdir); | |
94 | err = PTR_ERR(whiteout); | |
95 | if (IS_ERR(whiteout)) | |
96 | return err; | |
97 | ||
98 | if (d_is_dir(dentry)) | |
99 | flags = RENAME_EXCHANGE; | |
100 | ||
101 | err = ovl_do_rename(wdir, whiteout, dir, dentry, flags); | |
102 | if (err) | |
103 | goto kill_whiteout; | |
104 | if (flags) | |
105 | ovl_cleanup(wdir, dentry); | |
106 | ||
107 | out: | |
108 | dput(whiteout); | |
109 | return err; | |
110 | ||
111 | kill_whiteout: | |
112 | ovl_cleanup(wdir, whiteout); | |
113 | goto out; | |
114 | } | |
115 | ||
f73cc77c AV |
116 | static int ovl_mkdir_real(struct inode *dir, struct dentry **newdentry, |
117 | umode_t mode) | |
118 | { | |
119 | int err; | |
120 | struct dentry *d, *dentry = *newdentry; | |
121 | ||
122 | err = ovl_do_mkdir(dir, dentry, mode); | |
123 | if (err) | |
124 | return err; | |
125 | ||
126 | if (likely(!d_unhashed(dentry))) | |
127 | return 0; | |
128 | ||
129 | /* | |
130 | * vfs_mkdir() may succeed and leave the dentry passed | |
131 | * to it unhashed and negative. If that happens, try to | |
132 | * lookup a new hashed and positive dentry. | |
133 | */ | |
134 | d = lookup_one_len(dentry->d_name.name, dentry->d_parent, | |
135 | dentry->d_name.len); | |
136 | if (IS_ERR(d)) { | |
137 | pr_warn("overlayfs: failed lookup after mkdir (%pd2, err=%i).\n", | |
138 | dentry, err); | |
139 | return PTR_ERR(d); | |
140 | } | |
141 | dput(dentry); | |
142 | *newdentry = d; | |
143 | ||
144 | return 0; | |
145 | } | |
146 | ||
95a1c815 MS |
147 | struct dentry *ovl_create_real(struct inode *dir, struct dentry *newdentry, |
148 | struct ovl_cattr *attr) | |
e9be9d5e MS |
149 | { |
150 | int err; | |
151 | ||
95a1c815 MS |
152 | if (IS_ERR(newdentry)) |
153 | return newdentry; | |
154 | ||
155 | err = -ESTALE; | |
e9be9d5e | 156 | if (newdentry->d_inode) |
95a1c815 | 157 | goto out; |
e9be9d5e | 158 | |
471ec5dc AG |
159 | if (attr->hardlink) { |
160 | err = ovl_do_link(attr->hardlink, dir, newdentry); | |
e9be9d5e | 161 | } else { |
32a3d848 | 162 | switch (attr->mode & S_IFMT) { |
e9be9d5e | 163 | case S_IFREG: |
6cf00764 | 164 | err = ovl_do_create(dir, newdentry, attr->mode); |
e9be9d5e MS |
165 | break; |
166 | ||
167 | case S_IFDIR: | |
f73cc77c AV |
168 | /* mkdir is special... */ |
169 | err = ovl_mkdir_real(dir, &newdentry, attr->mode); | |
e9be9d5e MS |
170 | break; |
171 | ||
172 | case S_IFCHR: | |
173 | case S_IFBLK: | |
174 | case S_IFIFO: | |
175 | case S_IFSOCK: | |
6cf00764 AG |
176 | err = ovl_do_mknod(dir, newdentry, attr->mode, |
177 | attr->rdev); | |
e9be9d5e MS |
178 | break; |
179 | ||
180 | case S_IFLNK: | |
6cf00764 | 181 | err = ovl_do_symlink(dir, newdentry, attr->link); |
e9be9d5e MS |
182 | break; |
183 | ||
184 | default: | |
185 | err = -EPERM; | |
186 | } | |
187 | } | |
188 | if (!err && WARN_ON(!newdentry->d_inode)) { | |
189 | /* | |
190 | * Not quite sure if non-instantiated dentry is legal or not. | |
191 | * VFS doesn't seem to care so check and warn here. | |
192 | */ | |
dd8ac699 | 193 | err = -EIO; |
e9be9d5e | 194 | } |
95a1c815 MS |
195 | out: |
196 | if (err) { | |
197 | dput(newdentry); | |
198 | return ERR_PTR(err); | |
199 | } | |
200 | return newdentry; | |
e9be9d5e MS |
201 | } |
202 | ||
137ec526 AG |
203 | struct dentry *ovl_create_temp(struct dentry *workdir, struct ovl_cattr *attr) |
204 | { | |
205 | return ovl_create_real(d_inode(workdir), ovl_lookup_temp(workdir), | |
206 | attr); | |
207 | } | |
208 | ||
21a22878 AG |
209 | static int ovl_set_opaque_xerr(struct dentry *dentry, struct dentry *upper, |
210 | int xerr) | |
e9be9d5e | 211 | { |
5cf5b477 MS |
212 | int err; |
213 | ||
21a22878 | 214 | err = ovl_check_setxattr(dentry, upper, OVL_XATTR_OPAQUE, "y", 1, xerr); |
5cf5b477 MS |
215 | if (!err) |
216 | ovl_dentry_set_opaque(dentry); | |
217 | ||
218 | return err; | |
e9be9d5e MS |
219 | } |
220 | ||
21a22878 AG |
221 | static int ovl_set_opaque(struct dentry *dentry, struct dentry *upperdentry) |
222 | { | |
223 | /* | |
224 | * Fail with -EIO when trying to create opaque dir and upper doesn't | |
225 | * support xattrs. ovl_rename() calls ovl_set_opaque_xerr(-EXDEV) to | |
226 | * return a specific error for noxattr case. | |
227 | */ | |
228 | return ovl_set_opaque_xerr(dentry, upperdentry, -EIO); | |
229 | } | |
230 | ||
01b39dcc AG |
231 | /* |
232 | * Common operations required to be done after creation of file on upper. | |
233 | * If @hardlink is false, then @inode is a pre-allocated inode, we may or | |
234 | * may not use to instantiate the new dentry. | |
235 | */ | |
236 | static int ovl_instantiate(struct dentry *dentry, struct inode *inode, | |
237 | struct dentry *newdentry, bool hardlink) | |
72e48481 | 238 | { |
01b39dcc AG |
239 | struct ovl_inode_params oip = { |
240 | .upperdentry = newdentry, | |
241 | .newinode = inode, | |
242 | }; | |
243 | ||
d9854c87 | 244 | ovl_dir_modified(dentry->d_parent, false); |
55acc661 | 245 | ovl_dentry_set_upper_alias(dentry); |
51f7e52d | 246 | if (!hardlink) { |
01b39dcc AG |
247 | /* |
248 | * ovl_obtain_alias() can be called after ovl_create_real() | |
249 | * and before we get here, so we may get an inode from cache | |
250 | * with the same real upperdentry that is not the inode we | |
251 | * pre-allocated. In this case we will use the cached inode | |
252 | * to instantiate the new dentry. | |
253 | * | |
254 | * XXX: if we ever use ovl_obtain_alias() to decode directory | |
255 | * file handles, need to use ovl_get_inode_locked() and | |
256 | * d_instantiate_new() here to prevent from creating two | |
257 | * hashed directory inode aliases. | |
258 | */ | |
259 | inode = ovl_get_inode(dentry->d_sb, &oip); | |
acf3062a | 260 | if (IS_ERR(inode)) |
01b39dcc | 261 | return PTR_ERR(inode); |
51f7e52d | 262 | } else { |
09d8b586 MS |
263 | WARN_ON(ovl_inode_real(inode) != d_inode(newdentry)); |
264 | dput(newdentry); | |
51f7e52d MS |
265 | inc_nlink(inode); |
266 | } | |
01b39dcc | 267 | |
72e48481 | 268 | d_instantiate(dentry, inode); |
01b39dcc AG |
269 | if (inode != oip.newinode) { |
270 | pr_warn_ratelimited("overlayfs: newly created inode found in cache (%pd2)\n", | |
271 | dentry); | |
272 | } | |
273 | ||
5b6c9053 AG |
274 | /* Force lookup of new upper hardlink to find its lower */ |
275 | if (hardlink) | |
276 | d_drop(dentry); | |
01b39dcc AG |
277 | |
278 | return 0; | |
72e48481 VG |
279 | } |
280 | ||
97c684cc AG |
281 | static bool ovl_type_merge(struct dentry *dentry) |
282 | { | |
283 | return OVL_TYPE_MERGE(ovl_path_type(dentry)); | |
284 | } | |
285 | ||
ee1d6d37 AG |
286 | static bool ovl_type_origin(struct dentry *dentry) |
287 | { | |
288 | return OVL_TYPE_ORIGIN(ovl_path_type(dentry)); | |
289 | } | |
290 | ||
e9be9d5e | 291 | static int ovl_create_upper(struct dentry *dentry, struct inode *inode, |
471ec5dc | 292 | struct ovl_cattr *attr) |
e9be9d5e MS |
293 | { |
294 | struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent); | |
295 | struct inode *udir = upperdir->d_inode; | |
296 | struct dentry *newdentry; | |
297 | int err; | |
298 | ||
471ec5dc | 299 | if (!attr->hardlink && !IS_POSIXACL(udir)) |
32a3d848 | 300 | attr->mode &= ~current_umask(); |
38b25697 | 301 | |
5955102c | 302 | inode_lock_nested(udir, I_MUTEX_PARENT); |
95a1c815 MS |
303 | newdentry = ovl_create_real(udir, |
304 | lookup_one_len(dentry->d_name.name, | |
305 | upperdir, | |
306 | dentry->d_name.len), | |
307 | attr); | |
e9be9d5e MS |
308 | err = PTR_ERR(newdentry); |
309 | if (IS_ERR(newdentry)) | |
310 | goto out_unlock; | |
e9be9d5e | 311 | |
4a99f3c8 | 312 | if (ovl_type_merge(dentry->d_parent) && d_is_dir(newdentry)) { |
97c684cc AG |
313 | /* Setting opaque here is just an optimization, allow to fail */ |
314 | ovl_set_opaque(dentry, newdentry); | |
315 | } | |
316 | ||
01b39dcc AG |
317 | err = ovl_instantiate(dentry, inode, newdentry, !!attr->hardlink); |
318 | if (err) | |
319 | goto out_cleanup; | |
e9be9d5e | 320 | out_unlock: |
5955102c | 321 | inode_unlock(udir); |
e9be9d5e | 322 | return err; |
01b39dcc AG |
323 | |
324 | out_cleanup: | |
325 | ovl_cleanup(udir, newdentry); | |
326 | dput(newdentry); | |
327 | goto out_unlock; | |
e9be9d5e MS |
328 | } |
329 | ||
e9be9d5e MS |
330 | static struct dentry *ovl_clear_empty(struct dentry *dentry, |
331 | struct list_head *list) | |
332 | { | |
333 | struct dentry *workdir = ovl_workdir(dentry); | |
334 | struct inode *wdir = workdir->d_inode; | |
335 | struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent); | |
336 | struct inode *udir = upperdir->d_inode; | |
337 | struct path upperpath; | |
338 | struct dentry *upper; | |
339 | struct dentry *opaquedir; | |
340 | struct kstat stat; | |
341 | int err; | |
342 | ||
cc6f67bc MS |
343 | if (WARN_ON(!workdir)) |
344 | return ERR_PTR(-EROFS); | |
345 | ||
e9be9d5e MS |
346 | err = ovl_lock_rename_workdir(workdir, upperdir); |
347 | if (err) | |
348 | goto out; | |
349 | ||
350 | ovl_path_upper(dentry, &upperpath); | |
a528d35e DH |
351 | err = vfs_getattr(&upperpath, &stat, |
352 | STATX_BASIC_STATS, AT_STATX_SYNC_AS_STAT); | |
e9be9d5e MS |
353 | if (err) |
354 | goto out_unlock; | |
355 | ||
356 | err = -ESTALE; | |
357 | if (!S_ISDIR(stat.mode)) | |
358 | goto out_unlock; | |
359 | upper = upperpath.dentry; | |
360 | if (upper->d_parent->d_inode != udir) | |
361 | goto out_unlock; | |
362 | ||
137ec526 | 363 | opaquedir = ovl_create_temp(workdir, OVL_CATTR(stat.mode)); |
e9be9d5e MS |
364 | err = PTR_ERR(opaquedir); |
365 | if (IS_ERR(opaquedir)) | |
366 | goto out_unlock; | |
367 | ||
e9be9d5e MS |
368 | err = ovl_copy_xattr(upper, opaquedir); |
369 | if (err) | |
370 | goto out_cleanup; | |
371 | ||
5cf5b477 | 372 | err = ovl_set_opaque(dentry, opaquedir); |
e9be9d5e MS |
373 | if (err) |
374 | goto out_cleanup; | |
375 | ||
5955102c | 376 | inode_lock(opaquedir->d_inode); |
e9be9d5e | 377 | err = ovl_set_attr(opaquedir, &stat); |
5955102c | 378 | inode_unlock(opaquedir->d_inode); |
e9be9d5e MS |
379 | if (err) |
380 | goto out_cleanup; | |
381 | ||
382 | err = ovl_do_rename(wdir, opaquedir, udir, upper, RENAME_EXCHANGE); | |
383 | if (err) | |
384 | goto out_cleanup; | |
385 | ||
386 | ovl_cleanup_whiteouts(upper, list); | |
387 | ovl_cleanup(wdir, upper); | |
388 | unlock_rename(workdir, upperdir); | |
389 | ||
390 | /* dentry's upper doesn't match now, get rid of it */ | |
391 | d_drop(dentry); | |
392 | ||
393 | return opaquedir; | |
394 | ||
395 | out_cleanup: | |
396 | ovl_cleanup(wdir, opaquedir); | |
e9be9d5e MS |
397 | dput(opaquedir); |
398 | out_unlock: | |
399 | unlock_rename(workdir, upperdir); | |
400 | out: | |
401 | return ERR_PTR(err); | |
402 | } | |
403 | ||
38b25697 MS |
404 | static int ovl_set_upper_acl(struct dentry *upperdentry, const char *name, |
405 | const struct posix_acl *acl) | |
406 | { | |
407 | void *buffer; | |
408 | size_t size; | |
409 | int err; | |
410 | ||
411 | if (!IS_ENABLED(CONFIG_FS_POSIX_ACL) || !acl) | |
412 | return 0; | |
413 | ||
14fa0856 | 414 | size = posix_acl_xattr_size(acl->a_count); |
38b25697 MS |
415 | buffer = kmalloc(size, GFP_KERNEL); |
416 | if (!buffer) | |
417 | return -ENOMEM; | |
418 | ||
14fa0856 | 419 | err = posix_acl_to_xattr(&init_user_ns, acl, buffer, size); |
38b25697 MS |
420 | if (err < 0) |
421 | goto out_free; | |
422 | ||
423 | err = vfs_setxattr(upperdentry, name, buffer, size, XATTR_CREATE); | |
424 | out_free: | |
425 | kfree(buffer); | |
426 | return err; | |
427 | } | |
428 | ||
e9be9d5e | 429 | static int ovl_create_over_whiteout(struct dentry *dentry, struct inode *inode, |
471ec5dc | 430 | struct ovl_cattr *cattr) |
e9be9d5e MS |
431 | { |
432 | struct dentry *workdir = ovl_workdir(dentry); | |
433 | struct inode *wdir = workdir->d_inode; | |
434 | struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent); | |
435 | struct inode *udir = upperdir->d_inode; | |
436 | struct dentry *upper; | |
437 | struct dentry *newdentry; | |
438 | int err; | |
38b25697 | 439 | struct posix_acl *acl, *default_acl; |
471ec5dc | 440 | bool hardlink = !!cattr->hardlink; |
e9be9d5e | 441 | |
cc6f67bc MS |
442 | if (WARN_ON(!workdir)) |
443 | return -EROFS; | |
444 | ||
38b25697 MS |
445 | if (!hardlink) { |
446 | err = posix_acl_create(dentry->d_parent->d_inode, | |
32a3d848 | 447 | &cattr->mode, &default_acl, &acl); |
38b25697 MS |
448 | if (err) |
449 | return err; | |
450 | } | |
451 | ||
e9be9d5e MS |
452 | err = ovl_lock_rename_workdir(workdir, upperdir); |
453 | if (err) | |
454 | goto out; | |
455 | ||
e9be9d5e MS |
456 | upper = lookup_one_len(dentry->d_name.name, upperdir, |
457 | dentry->d_name.len); | |
458 | err = PTR_ERR(upper); | |
459 | if (IS_ERR(upper)) | |
95a1c815 | 460 | goto out_unlock; |
e9be9d5e | 461 | |
5e127580 MS |
462 | err = -ESTALE; |
463 | if (d_is_negative(upper) || !IS_WHITEOUT(d_inode(upper))) | |
464 | goto out_dput; | |
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 | ||
91ff20f3 AG |
651 | static int ovl_set_link_redirect(struct dentry *dentry) |
652 | { | |
653 | const struct cred *old_cred; | |
654 | int err; | |
655 | ||
656 | old_cred = ovl_override_creds(dentry->d_sb); | |
657 | err = ovl_set_redirect(dentry, false); | |
658 | revert_creds(old_cred); | |
659 | ||
660 | return err; | |
661 | } | |
662 | ||
e9be9d5e MS |
663 | static int ovl_link(struct dentry *old, struct inode *newdir, |
664 | struct dentry *new) | |
665 | { | |
666 | int err; | |
51f7e52d | 667 | struct inode *inode; |
e9be9d5e MS |
668 | |
669 | err = ovl_want_write(old); | |
670 | if (err) | |
671 | goto out; | |
672 | ||
673 | err = ovl_copy_up(old); | |
674 | if (err) | |
675 | goto out_drop_write; | |
676 | ||
6cd07870 AG |
677 | err = ovl_copy_up(new->d_parent); |
678 | if (err) | |
679 | goto out_drop_write; | |
680 | ||
4120fe64 | 681 | if (ovl_is_metacopy_dentry(old)) { |
91ff20f3 | 682 | err = ovl_set_link_redirect(old); |
4120fe64 VG |
683 | if (err) |
684 | goto out_drop_write; | |
685 | } | |
686 | ||
0e32992f | 687 | err = ovl_nlink_start(old); |
5f8415d6 AG |
688 | if (err) |
689 | goto out_drop_write; | |
690 | ||
51f7e52d MS |
691 | inode = d_inode(old); |
692 | ihold(inode); | |
693 | ||
471ec5dc AG |
694 | err = ovl_create_or_link(new, inode, |
695 | &(struct ovl_cattr) {.hardlink = ovl_dentry_upper(old)}, | |
696 | ovl_type_origin(old)); | |
51f7e52d MS |
697 | if (err) |
698 | iput(inode); | |
e9be9d5e | 699 | |
0e32992f | 700 | ovl_nlink_end(old); |
e9be9d5e MS |
701 | out_drop_write: |
702 | ovl_drop_write(old); | |
703 | out: | |
704 | return err; | |
705 | } | |
706 | ||
9020df37 MS |
707 | static bool ovl_matches_upper(struct dentry *dentry, struct dentry *upper) |
708 | { | |
709 | return d_inode(ovl_dentry_upper(dentry)) == d_inode(upper); | |
710 | } | |
711 | ||
6d0a8a90 AG |
712 | static int ovl_remove_and_whiteout(struct dentry *dentry, |
713 | struct list_head *list) | |
e9be9d5e MS |
714 | { |
715 | struct dentry *workdir = ovl_workdir(dentry); | |
e9be9d5e | 716 | struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent); |
e9be9d5e MS |
717 | struct dentry *upper; |
718 | struct dentry *opaquedir = NULL; | |
719 | int err; | |
720 | ||
cc6f67bc MS |
721 | if (WARN_ON(!workdir)) |
722 | return -EROFS; | |
723 | ||
6d0a8a90 AG |
724 | if (!list_empty(list)) { |
725 | opaquedir = ovl_clear_empty(dentry, list); | |
30c17ebf MS |
726 | err = PTR_ERR(opaquedir); |
727 | if (IS_ERR(opaquedir)) | |
728 | goto out; | |
e9be9d5e MS |
729 | } |
730 | ||
731 | err = ovl_lock_rename_workdir(workdir, upperdir); | |
732 | if (err) | |
733 | goto out_dput; | |
734 | ||
cfc9fde0 MP |
735 | upper = lookup_one_len(dentry->d_name.name, upperdir, |
736 | dentry->d_name.len); | |
737 | err = PTR_ERR(upper); | |
738 | if (IS_ERR(upper)) | |
e9be9d5e MS |
739 | goto out_unlock; |
740 | ||
cfc9fde0 MP |
741 | err = -ESTALE; |
742 | if ((opaquedir && upper != opaquedir) || | |
743 | (!opaquedir && ovl_dentry_upper(dentry) && | |
9020df37 | 744 | !ovl_matches_upper(dentry, upper))) { |
cfc9fde0 MP |
745 | goto out_dput_upper; |
746 | } | |
e9be9d5e | 747 | |
e7dd0e71 | 748 | err = ovl_cleanup_and_whiteout(workdir, d_inode(upperdir), upper); |
cfc9fde0 | 749 | if (err) |
e7dd0e71 | 750 | goto out_d_drop; |
e9be9d5e | 751 | |
d9854c87 | 752 | ovl_dir_modified(dentry->d_parent, true); |
e9be9d5e MS |
753 | out_d_drop: |
754 | d_drop(dentry); | |
cfc9fde0 MP |
755 | out_dput_upper: |
756 | dput(upper); | |
e9be9d5e MS |
757 | out_unlock: |
758 | unlock_rename(workdir, upperdir); | |
759 | out_dput: | |
760 | dput(opaquedir); | |
761 | out: | |
762 | return err; | |
e9be9d5e MS |
763 | } |
764 | ||
6d0a8a90 AG |
765 | static int ovl_remove_upper(struct dentry *dentry, bool is_dir, |
766 | struct list_head *list) | |
e9be9d5e MS |
767 | { |
768 | struct dentry *upperdir = ovl_dentry_upper(dentry->d_parent); | |
769 | struct inode *dir = upperdir->d_inode; | |
11f37104 | 770 | struct dentry *upper; |
d1595119 | 771 | struct dentry *opaquedir = NULL; |
e9be9d5e MS |
772 | int err; |
773 | ||
6d0a8a90 AG |
774 | if (!list_empty(list)) { |
775 | opaquedir = ovl_clear_empty(dentry, list); | |
d1595119 AG |
776 | err = PTR_ERR(opaquedir); |
777 | if (IS_ERR(opaquedir)) | |
778 | goto out; | |
779 | } | |
780 | ||
5955102c | 781 | inode_lock_nested(dir, I_MUTEX_PARENT); |
11f37104 MS |
782 | upper = lookup_one_len(dentry->d_name.name, upperdir, |
783 | dentry->d_name.len); | |
784 | err = PTR_ERR(upper); | |
785 | if (IS_ERR(upper)) | |
786 | goto out_unlock; | |
787 | ||
e9be9d5e | 788 | err = -ESTALE; |
d1595119 | 789 | if ((opaquedir && upper != opaquedir) || |
9020df37 | 790 | (!opaquedir && !ovl_matches_upper(dentry, upper))) |
d1595119 AG |
791 | goto out_dput_upper; |
792 | ||
793 | if (is_dir) | |
794 | err = vfs_rmdir(dir, upper); | |
795 | else | |
796 | err = vfs_unlink(dir, upper, NULL); | |
d9854c87 | 797 | ovl_dir_modified(dentry->d_parent, ovl_type_origin(dentry)); |
e9be9d5e MS |
798 | |
799 | /* | |
800 | * Keeping this dentry hashed would mean having to release | |
801 | * upperpath/lowerpath, which could only be done if we are the | |
802 | * sole user of this dentry. Too tricky... Just unhash for | |
803 | * now. | |
804 | */ | |
ce9113bb RW |
805 | if (!err) |
806 | d_drop(dentry); | |
d1595119 AG |
807 | out_dput_upper: |
808 | dput(upper); | |
11f37104 | 809 | out_unlock: |
5955102c | 810 | inode_unlock(dir); |
d1595119 AG |
811 | dput(opaquedir); |
812 | out: | |
e9be9d5e MS |
813 | return err; |
814 | } | |
815 | ||
6d0a8a90 AG |
816 | static bool ovl_pure_upper(struct dentry *dentry) |
817 | { | |
818 | return !ovl_dentry_lower(dentry) && | |
819 | !ovl_test_flag(OVL_WHITEOUTS, d_inode(dentry)); | |
820 | } | |
821 | ||
e9be9d5e MS |
822 | static int ovl_do_remove(struct dentry *dentry, bool is_dir) |
823 | { | |
e9be9d5e | 824 | int err; |
1175b6b8 | 825 | const struct cred *old_cred; |
d9854c87 | 826 | struct dentry *upperdentry; |
6d0a8a90 AG |
827 | bool lower_positive = ovl_lower_positive(dentry); |
828 | LIST_HEAD(list); | |
829 | ||
830 | /* No need to clean pure upper removed by vfs_rmdir() */ | |
831 | if (is_dir && (lower_positive || !ovl_pure_upper(dentry))) { | |
832 | err = ovl_check_empty_dir(dentry, &list); | |
833 | if (err) | |
834 | goto out; | |
835 | } | |
1175b6b8 | 836 | |
e9be9d5e MS |
837 | err = ovl_want_write(dentry); |
838 | if (err) | |
839 | goto out; | |
840 | ||
841 | err = ovl_copy_up(dentry->d_parent); | |
842 | if (err) | |
843 | goto out_drop_write; | |
844 | ||
0e32992f | 845 | err = ovl_nlink_start(dentry); |
5f8415d6 AG |
846 | if (err) |
847 | goto out_drop_write; | |
e9be9d5e | 848 | |
1175b6b8 | 849 | old_cred = ovl_override_creds(dentry->d_sb); |
6d0a8a90 AG |
850 | if (!lower_positive) |
851 | err = ovl_remove_upper(dentry, is_dir, &list); | |
1175b6b8 | 852 | else |
6d0a8a90 | 853 | err = ovl_remove_and_whiteout(dentry, &list); |
1175b6b8 | 854 | revert_creds(old_cred); |
dbc816d0 MS |
855 | if (!err) { |
856 | if (is_dir) | |
857 | clear_nlink(dentry->d_inode); | |
858 | else | |
859 | drop_nlink(dentry->d_inode); | |
860 | } | |
0e32992f | 861 | ovl_nlink_end(dentry); |
d9854c87 MS |
862 | |
863 | /* | |
864 | * Copy ctime | |
865 | * | |
866 | * Note: we fail to update ctime if there was no copy-up, only a | |
867 | * whiteout | |
868 | */ | |
869 | upperdentry = ovl_dentry_upper(dentry); | |
870 | if (upperdentry) | |
871 | ovl_copyattr(d_inode(upperdentry), d_inode(dentry)); | |
872 | ||
e9be9d5e MS |
873 | out_drop_write: |
874 | ovl_drop_write(dentry); | |
875 | out: | |
6d0a8a90 | 876 | ovl_cache_free(&list); |
e9be9d5e MS |
877 | return err; |
878 | } | |
879 | ||
880 | static int ovl_unlink(struct inode *dir, struct dentry *dentry) | |
881 | { | |
882 | return ovl_do_remove(dentry, false); | |
883 | } | |
884 | ||
885 | static int ovl_rmdir(struct inode *dir, struct dentry *dentry) | |
886 | { | |
887 | return ovl_do_remove(dentry, true); | |
888 | } | |
889 | ||
370e55ac MS |
890 | static bool ovl_type_merge_or_lower(struct dentry *dentry) |
891 | { | |
892 | enum ovl_path_type type = ovl_path_type(dentry); | |
893 | ||
894 | return OVL_TYPE_MERGE(type) || !OVL_TYPE_UPPER(type); | |
895 | } | |
896 | ||
a6c60655 MS |
897 | static bool ovl_can_move(struct dentry *dentry) |
898 | { | |
899 | return ovl_redirect_dir(dentry->d_sb) || | |
900 | !d_is_dir(dentry) || !ovl_type_merge_or_lower(dentry); | |
901 | } | |
902 | ||
7bb08383 | 903 | static char *ovl_get_redirect(struct dentry *dentry, bool abs_redirect) |
a6c60655 MS |
904 | { |
905 | char *buf, *ret; | |
906 | struct dentry *d, *tmp; | |
3ea22a71 | 907 | int buflen = ovl_redirect_max + 1; |
a6c60655 | 908 | |
7bb08383 | 909 | if (!abs_redirect) { |
a6c60655 MS |
910 | ret = kstrndup(dentry->d_name.name, dentry->d_name.len, |
911 | GFP_KERNEL); | |
912 | goto out; | |
913 | } | |
914 | ||
0ee931c4 | 915 | buf = ret = kmalloc(buflen, GFP_KERNEL); |
a6c60655 MS |
916 | if (!buf) |
917 | goto out; | |
918 | ||
919 | buflen--; | |
920 | buf[buflen] = '\0'; | |
921 | for (d = dget(dentry); !IS_ROOT(d);) { | |
922 | const char *name; | |
923 | int thislen; | |
924 | ||
925 | spin_lock(&d->d_lock); | |
926 | name = ovl_dentry_get_redirect(d); | |
927 | if (name) { | |
928 | thislen = strlen(name); | |
929 | } else { | |
930 | name = d->d_name.name; | |
931 | thislen = d->d_name.len; | |
932 | } | |
933 | ||
934 | /* If path is too long, fall back to userspace move */ | |
935 | if (thislen + (name[0] != '/') > buflen) { | |
936 | ret = ERR_PTR(-EXDEV); | |
937 | spin_unlock(&d->d_lock); | |
938 | goto out_put; | |
939 | } | |
940 | ||
941 | buflen -= thislen; | |
942 | memcpy(&buf[buflen], name, thislen); | |
943 | tmp = dget_dlock(d->d_parent); | |
944 | spin_unlock(&d->d_lock); | |
945 | ||
946 | dput(d); | |
947 | d = tmp; | |
948 | ||
949 | /* Absolute redirect: finished */ | |
950 | if (buf[buflen] == '/') | |
951 | break; | |
952 | buflen--; | |
953 | buf[buflen] = '/'; | |
954 | } | |
955 | ret = kstrdup(&buf[buflen], GFP_KERNEL); | |
956 | out_put: | |
957 | dput(d); | |
958 | kfree(buf); | |
959 | out: | |
960 | return ret ? ret : ERR_PTR(-ENOMEM); | |
961 | } | |
962 | ||
7bb08383 VG |
963 | static bool ovl_need_absolute_redirect(struct dentry *dentry, bool samedir) |
964 | { | |
965 | struct dentry *lowerdentry; | |
966 | ||
967 | if (!samedir) | |
968 | return true; | |
969 | ||
970 | if (d_is_dir(dentry)) | |
971 | return false; | |
972 | ||
973 | /* | |
974 | * For non-dir hardlinked files, we need absolute redirects | |
975 | * in general as two upper hardlinks could be in different | |
976 | * dirs. We could put a relative redirect now and convert | |
977 | * it to absolute redirect later. But when nlink > 1 and | |
978 | * indexing is on, that means relative redirect needs to be | |
979 | * converted to absolute during copy up of another lower | |
980 | * hardllink as well. | |
981 | * | |
982 | * So without optimizing too much, just check if lower is | |
983 | * a hard link or not. If lower is hard link, put absolute | |
984 | * redirect. | |
985 | */ | |
986 | lowerdentry = ovl_dentry_lower(dentry); | |
987 | return (d_inode(lowerdentry)->i_nlink > 1); | |
988 | } | |
989 | ||
a6c60655 MS |
990 | static int ovl_set_redirect(struct dentry *dentry, bool samedir) |
991 | { | |
992 | int err; | |
993 | const char *redirect = ovl_dentry_get_redirect(dentry); | |
7bb08383 | 994 | bool absolute_redirect = ovl_need_absolute_redirect(dentry, samedir); |
a6c60655 | 995 | |
7bb08383 | 996 | if (redirect && (!absolute_redirect || redirect[0] == '/')) |
a6c60655 MS |
997 | return 0; |
998 | ||
7bb08383 | 999 | redirect = ovl_get_redirect(dentry, absolute_redirect); |
a6c60655 MS |
1000 | if (IS_ERR(redirect)) |
1001 | return PTR_ERR(redirect); | |
1002 | ||
21a22878 AG |
1003 | err = ovl_check_setxattr(dentry, ovl_dentry_upper(dentry), |
1004 | OVL_XATTR_REDIRECT, | |
1005 | redirect, strlen(redirect), -EXDEV); | |
a6c60655 MS |
1006 | if (!err) { |
1007 | spin_lock(&dentry->d_lock); | |
1008 | ovl_dentry_set_redirect(dentry, redirect); | |
1009 | spin_unlock(&dentry->d_lock); | |
1010 | } else { | |
1011 | kfree(redirect); | |
da2e6b7e AG |
1012 | pr_warn_ratelimited("overlayfs: failed to set redirect (%i)\n", |
1013 | err); | |
a6c60655 MS |
1014 | /* Fall back to userspace copy-up */ |
1015 | err = -EXDEV; | |
1016 | } | |
1017 | return err; | |
1018 | } | |
1019 | ||
6c02cb59 MS |
1020 | static int ovl_rename(struct inode *olddir, struct dentry *old, |
1021 | struct inode *newdir, struct dentry *new, | |
1022 | unsigned int flags) | |
e9be9d5e MS |
1023 | { |
1024 | int err; | |
e9be9d5e MS |
1025 | struct dentry *old_upperdir; |
1026 | struct dentry *new_upperdir; | |
1027 | struct dentry *olddentry; | |
1028 | struct dentry *newdentry; | |
1029 | struct dentry *trap; | |
1030 | bool old_opaque; | |
1031 | bool new_opaque; | |
e9be9d5e | 1032 | bool cleanup_whiteout = false; |
0e32992f | 1033 | bool update_nlink = false; |
e9be9d5e | 1034 | bool overwrite = !(flags & RENAME_EXCHANGE); |
e36cb0b8 | 1035 | bool is_dir = d_is_dir(old); |
370e55ac | 1036 | bool new_is_dir = d_is_dir(new); |
a6c60655 | 1037 | bool samedir = olddir == newdir; |
e9be9d5e MS |
1038 | struct dentry *opaquedir = NULL; |
1039 | const struct cred *old_cred = NULL; | |
6d0a8a90 | 1040 | LIST_HEAD(list); |
e9be9d5e MS |
1041 | |
1042 | err = -EINVAL; | |
1043 | if (flags & ~(RENAME_EXCHANGE | RENAME_NOREPLACE)) | |
1044 | goto out; | |
1045 | ||
1046 | flags &= ~RENAME_NOREPLACE; | |
1047 | ||
e9be9d5e | 1048 | /* Don't copy up directory trees */ |
e9be9d5e | 1049 | err = -EXDEV; |
a6c60655 | 1050 | if (!ovl_can_move(old)) |
370e55ac | 1051 | goto out; |
a6c60655 | 1052 | if (!overwrite && !ovl_can_move(new)) |
e9be9d5e | 1053 | goto out; |
e9be9d5e | 1054 | |
6d0a8a90 AG |
1055 | if (overwrite && new_is_dir && !ovl_pure_upper(new)) { |
1056 | err = ovl_check_empty_dir(new, &list); | |
1057 | if (err) | |
1058 | goto out; | |
1059 | } | |
1060 | ||
1061 | if (overwrite) { | |
1062 | if (ovl_lower_positive(old)) { | |
1063 | if (!ovl_dentry_is_whiteout(new)) { | |
1064 | /* Whiteout source */ | |
1065 | flags |= RENAME_WHITEOUT; | |
1066 | } else { | |
1067 | /* Switch whiteouts */ | |
1068 | flags |= RENAME_EXCHANGE; | |
1069 | } | |
1070 | } else if (is_dir && ovl_dentry_is_whiteout(new)) { | |
1071 | flags |= RENAME_EXCHANGE; | |
1072 | cleanup_whiteout = true; | |
1073 | } | |
1074 | } | |
1075 | ||
e9be9d5e MS |
1076 | err = ovl_want_write(old); |
1077 | if (err) | |
1078 | goto out; | |
1079 | ||
1080 | err = ovl_copy_up(old); | |
1081 | if (err) | |
1082 | goto out_drop_write; | |
1083 | ||
1084 | err = ovl_copy_up(new->d_parent); | |
1085 | if (err) | |
1086 | goto out_drop_write; | |
1087 | if (!overwrite) { | |
1088 | err = ovl_copy_up(new); | |
1089 | if (err) | |
1090 | goto out_drop_write; | |
0e32992f AG |
1091 | } else if (d_inode(new)) { |
1092 | err = ovl_nlink_start(new); | |
5f8415d6 AG |
1093 | if (err) |
1094 | goto out_drop_write; | |
0e32992f AG |
1095 | |
1096 | update_nlink = true; | |
e9be9d5e MS |
1097 | } |
1098 | ||
1175b6b8 | 1099 | old_cred = ovl_override_creds(old->d_sb); |
e9be9d5e | 1100 | |
6d0a8a90 AG |
1101 | if (!list_empty(&list)) { |
1102 | opaquedir = ovl_clear_empty(new, &list); | |
e9be9d5e MS |
1103 | err = PTR_ERR(opaquedir); |
1104 | if (IS_ERR(opaquedir)) { | |
1105 | opaquedir = NULL; | |
1106 | goto out_revert_creds; | |
1107 | } | |
1108 | } | |
1109 | ||
e9be9d5e MS |
1110 | old_upperdir = ovl_dentry_upper(old->d_parent); |
1111 | new_upperdir = ovl_dentry_upper(new->d_parent); | |
1112 | ||
ee1d6d37 AG |
1113 | if (!samedir) { |
1114 | /* | |
1115 | * When moving a merge dir or non-dir with copy up origin into | |
f3a15685 AG |
1116 | * a new parent, we are marking the new parent dir "impure". |
1117 | * When ovl_iterate() iterates an "impure" upper dir, it will | |
1118 | * lookup the origin inodes of the entries to fill d_ino. | |
ee1d6d37 | 1119 | */ |
f3a15685 | 1120 | if (ovl_type_origin(old)) { |
ee1d6d37 AG |
1121 | err = ovl_set_impure(new->d_parent, new_upperdir); |
1122 | if (err) | |
1123 | goto out_revert_creds; | |
1124 | } | |
f3a15685 | 1125 | if (!overwrite && ovl_type_origin(new)) { |
ee1d6d37 AG |
1126 | err = ovl_set_impure(old->d_parent, old_upperdir); |
1127 | if (err) | |
1128 | goto out_revert_creds; | |
1129 | } | |
1130 | } | |
1131 | ||
e9be9d5e MS |
1132 | trap = lock_rename(new_upperdir, old_upperdir); |
1133 | ||
11f37104 MS |
1134 | olddentry = lookup_one_len(old->d_name.name, old_upperdir, |
1135 | old->d_name.len); | |
1136 | err = PTR_ERR(olddentry); | |
1137 | if (IS_ERR(olddentry)) | |
1138 | goto out_unlock; | |
1139 | ||
1140 | err = -ESTALE; | |
9020df37 | 1141 | if (!ovl_matches_upper(old, olddentry)) |
11f37104 MS |
1142 | goto out_dput_old; |
1143 | ||
1144 | newdentry = lookup_one_len(new->d_name.name, new_upperdir, | |
1145 | new->d_name.len); | |
1146 | err = PTR_ERR(newdentry); | |
1147 | if (IS_ERR(newdentry)) | |
1148 | goto out_dput_old; | |
1149 | ||
3ee23ff1 MS |
1150 | old_opaque = ovl_dentry_is_opaque(old); |
1151 | new_opaque = ovl_dentry_is_opaque(new); | |
1152 | ||
11f37104 | 1153 | err = -ESTALE; |
09d8b586 | 1154 | if (d_inode(new) && ovl_dentry_upper(new)) { |
e9be9d5e | 1155 | if (opaquedir) { |
11f37104 MS |
1156 | if (newdentry != opaquedir) |
1157 | goto out_dput; | |
e9be9d5e | 1158 | } else { |
9020df37 | 1159 | if (!ovl_matches_upper(new, newdentry)) |
11f37104 | 1160 | goto out_dput; |
e9be9d5e MS |
1161 | } |
1162 | } else { | |
11f37104 MS |
1163 | if (!d_is_negative(newdentry) && |
1164 | (!new_opaque || !ovl_is_whiteout(newdentry))) | |
1165 | goto out_dput; | |
e9be9d5e MS |
1166 | } |
1167 | ||
e9be9d5e MS |
1168 | if (olddentry == trap) |
1169 | goto out_dput; | |
1170 | if (newdentry == trap) | |
1171 | goto out_dput; | |
1172 | ||
804032fa MS |
1173 | if (WARN_ON(olddentry->d_inode == newdentry->d_inode)) |
1174 | goto out_dput; | |
1175 | ||
5cf5b477 | 1176 | err = 0; |
7bb08383 VG |
1177 | if (ovl_type_merge_or_lower(old)) |
1178 | err = ovl_set_redirect(old, samedir); | |
1179 | else if (is_dir && !old_opaque && ovl_type_merge(new->d_parent)) | |
1180 | err = ovl_set_opaque_xerr(old, olddentry, -EXDEV); | |
1181 | if (err) | |
1182 | goto out_dput; | |
1183 | ||
1184 | if (!overwrite && ovl_type_merge_or_lower(new)) | |
1185 | err = ovl_set_redirect(new, samedir); | |
1186 | else if (!overwrite && new_is_dir && !new_opaque && | |
1187 | ovl_type_merge(old->d_parent)) | |
1188 | err = ovl_set_opaque_xerr(new, newdentry, -EXDEV); | |
1189 | if (err) | |
1190 | goto out_dput; | |
e9be9d5e | 1191 | |
3ee23ff1 MS |
1192 | err = ovl_do_rename(old_upperdir->d_inode, olddentry, |
1193 | new_upperdir->d_inode, newdentry, flags); | |
1194 | if (err) | |
e9be9d5e | 1195 | goto out_dput; |
e9be9d5e MS |
1196 | |
1197 | if (cleanup_whiteout) | |
1198 | ovl_cleanup(old_upperdir->d_inode, newdentry); | |
1199 | ||
f681eb1d AG |
1200 | if (overwrite && d_inode(new)) { |
1201 | if (new_is_dir) | |
1202 | clear_nlink(d_inode(new)); | |
1203 | else | |
1204 | drop_nlink(d_inode(new)); | |
1205 | } | |
1206 | ||
d9854c87 MS |
1207 | ovl_dir_modified(old->d_parent, ovl_type_origin(old) || |
1208 | (!overwrite && ovl_type_origin(new))); | |
1209 | ovl_dir_modified(new->d_parent, ovl_type_origin(old) || | |
1210 | (d_inode(new) && ovl_type_origin(new))); | |
1211 | ||
1212 | /* copy ctime: */ | |
1213 | ovl_copyattr(d_inode(olddentry), d_inode(old)); | |
1214 | if (d_inode(new) && ovl_dentry_upper(new)) | |
1215 | ovl_copyattr(d_inode(newdentry), d_inode(new)); | |
e9be9d5e MS |
1216 | |
1217 | out_dput: | |
1218 | dput(newdentry); | |
11f37104 MS |
1219 | out_dput_old: |
1220 | dput(olddentry); | |
e9be9d5e MS |
1221 | out_unlock: |
1222 | unlock_rename(new_upperdir, old_upperdir); | |
1223 | out_revert_creds: | |
1175b6b8 | 1224 | revert_creds(old_cred); |
0e32992f AG |
1225 | if (update_nlink) |
1226 | ovl_nlink_end(new); | |
e9be9d5e MS |
1227 | out_drop_write: |
1228 | ovl_drop_write(old); | |
1229 | out: | |
1230 | dput(opaquedir); | |
6d0a8a90 | 1231 | ovl_cache_free(&list); |
e9be9d5e MS |
1232 | return err; |
1233 | } | |
1234 | ||
1235 | const struct inode_operations ovl_dir_inode_operations = { | |
1236 | .lookup = ovl_lookup, | |
1237 | .mkdir = ovl_mkdir, | |
1238 | .symlink = ovl_symlink, | |
1239 | .unlink = ovl_unlink, | |
1240 | .rmdir = ovl_rmdir, | |
6c02cb59 | 1241 | .rename = ovl_rename, |
e9be9d5e MS |
1242 | .link = ovl_link, |
1243 | .setattr = ovl_setattr, | |
1244 | .create = ovl_create, | |
1245 | .mknod = ovl_mknod, | |
1246 | .permission = ovl_permission, | |
5b712091 | 1247 | .getattr = ovl_getattr, |
e9be9d5e | 1248 | .listxattr = ovl_listxattr, |
39a25b2b | 1249 | .get_acl = ovl_get_acl, |
d719e8f2 | 1250 | .update_time = ovl_update_time, |
e9be9d5e | 1251 | }; |