1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 *
4 * Copyright (C) 2019-2021 Paragon Software GmbH, All rights reserved.
5 *
6 */
7
8 #include <linux/fs.h>
9 #include <linux/nls.h>
10
11 #include "debug.h"
12 #include "ntfs.h"
13 #include "ntfs_fs.h"
14
15 /*
16 * fill_name_de - Format NTFS_DE in @buf.
17 */
fill_name_de(struct ntfs_sb_info * sbi,void * buf,const struct qstr * name,const struct cpu_str * uni)18 int fill_name_de(struct ntfs_sb_info *sbi, void *buf, const struct qstr *name,
19 const struct cpu_str *uni)
20 {
21 int err;
22 struct NTFS_DE *e = buf;
23 u16 data_size;
24 struct ATTR_FILE_NAME *fname = (struct ATTR_FILE_NAME *)(e + 1);
25
26 #ifndef CONFIG_NTFS3_64BIT_CLUSTER
27 e->ref.high = fname->home.high = 0;
28 #endif
29 if (uni) {
30 #ifdef __BIG_ENDIAN
31 int ulen = uni->len;
32 __le16 *uname = fname->name;
33 const u16 *name_cpu = uni->name;
34
35 while (ulen--)
36 *uname++ = cpu_to_le16(*name_cpu++);
37 #else
38 memcpy(fname->name, uni->name, uni->len * sizeof(u16));
39 #endif
40 fname->name_len = uni->len;
41
42 } else {
43 /* Convert input string to unicode. */
44 err = ntfs_nls_to_utf16(sbi, name->name, name->len,
45 (struct cpu_str *)&fname->name_len,
46 NTFS_NAME_LEN, UTF16_LITTLE_ENDIAN);
47 if (err < 0)
48 return err;
49 }
50
51 fname->type = FILE_NAME_POSIX;
52 data_size = fname_full_size(fname);
53
54 e->size = cpu_to_le16(ALIGN(data_size, 8) + sizeof(struct NTFS_DE));
55 e->key_size = cpu_to_le16(data_size);
56 e->flags = 0;
57 e->res = 0;
58
59 return 0;
60 }
61
62 /*
63 * ntfs_lookup - inode_operations::lookup
64 */
ntfs_lookup(struct inode * dir,struct dentry * dentry,u32 flags)65 static struct dentry *ntfs_lookup(struct inode *dir, struct dentry *dentry,
66 u32 flags)
67 {
68 struct ntfs_inode *ni = ntfs_i(dir);
69 struct cpu_str *uni = __getname();
70 struct inode *inode;
71 int err;
72
73 if (!uni)
74 inode = ERR_PTR(-ENOMEM);
75 else {
76 err = ntfs_nls_to_utf16(ni->mi.sbi, dentry->d_name.name,
77 dentry->d_name.len, uni, NTFS_NAME_LEN,
78 UTF16_HOST_ENDIAN);
79 if (err < 0)
80 inode = ERR_PTR(err);
81 else {
82 ni_lock(ni);
83 inode = dir_search_u(dir, uni, NULL);
84 ni_unlock(ni);
85 }
86 __putname(uni);
87 }
88
89 return d_splice_alias(inode, dentry);
90 }
91
92 /*
93 * ntfs_create - inode_operations::create
94 */
ntfs_create(struct user_namespace * mnt_userns,struct inode * dir,struct dentry * dentry,umode_t mode,bool excl)95 static int ntfs_create(struct user_namespace *mnt_userns, struct inode *dir,
96 struct dentry *dentry, umode_t mode, bool excl)
97 {
98 struct inode *inode;
99
100 inode = ntfs_create_inode(mnt_userns, dir, dentry, NULL, S_IFREG | mode,
101 0, NULL, 0, NULL);
102
103 return IS_ERR(inode) ? PTR_ERR(inode) : 0;
104 }
105
106 /*
107 * ntfs_mknod
108 *
109 * inode_operations::mknod
110 */
ntfs_mknod(struct user_namespace * mnt_userns,struct inode * dir,struct dentry * dentry,umode_t mode,dev_t rdev)111 static int ntfs_mknod(struct user_namespace *mnt_userns, struct inode *dir,
112 struct dentry *dentry, umode_t mode, dev_t rdev)
113 {
114 struct inode *inode;
115
116 inode = ntfs_create_inode(mnt_userns, dir, dentry, NULL, mode, rdev,
117 NULL, 0, NULL);
118
119 return IS_ERR(inode) ? PTR_ERR(inode) : 0;
120 }
121
122 /*
123 * ntfs_link - inode_operations::link
124 */
ntfs_link(struct dentry * ode,struct inode * dir,struct dentry * de)125 static int ntfs_link(struct dentry *ode, struct inode *dir, struct dentry *de)
126 {
127 int err;
128 struct inode *inode = d_inode(ode);
129 struct ntfs_inode *ni = ntfs_i(inode);
130
131 if (S_ISDIR(inode->i_mode))
132 return -EPERM;
133
134 if (inode->i_nlink >= NTFS_LINK_MAX)
135 return -EMLINK;
136
137 ni_lock_dir(ntfs_i(dir));
138 if (inode != dir)
139 ni_lock(ni);
140
141 inc_nlink(inode);
142 ihold(inode);
143
144 err = ntfs_link_inode(inode, de);
145
146 if (!err) {
147 dir->i_ctime = dir->i_mtime = inode->i_ctime =
148 current_time(dir);
149 mark_inode_dirty(inode);
150 mark_inode_dirty(dir);
151 d_instantiate(de, inode);
152 } else {
153 drop_nlink(inode);
154 iput(inode);
155 }
156
157 if (inode != dir)
158 ni_unlock(ni);
159 ni_unlock(ntfs_i(dir));
160
161 return err;
162 }
163
164 /*
165 * ntfs_unlink - inode_operations::unlink
166 */
ntfs_unlink(struct inode * dir,struct dentry * dentry)167 static int ntfs_unlink(struct inode *dir, struct dentry *dentry)
168 {
169 struct ntfs_inode *ni = ntfs_i(dir);
170 int err;
171
172 ni_lock_dir(ni);
173
174 err = ntfs_unlink_inode(dir, dentry);
175
176 ni_unlock(ni);
177
178 return err;
179 }
180
181 /*
182 * ntfs_symlink - inode_operations::symlink
183 */
ntfs_symlink(struct user_namespace * mnt_userns,struct inode * dir,struct dentry * dentry,const char * symname)184 static int ntfs_symlink(struct user_namespace *mnt_userns, struct inode *dir,
185 struct dentry *dentry, const char *symname)
186 {
187 u32 size = strlen(symname);
188 struct inode *inode;
189
190 inode = ntfs_create_inode(mnt_userns, dir, dentry, NULL, S_IFLNK | 0777,
191 0, symname, size, NULL);
192
193 return IS_ERR(inode) ? PTR_ERR(inode) : 0;
194 }
195
196 /*
197 * ntfs_mkdir- inode_operations::mkdir
198 */
ntfs_mkdir(struct user_namespace * mnt_userns,struct inode * dir,struct dentry * dentry,umode_t mode)199 static int ntfs_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
200 struct dentry *dentry, umode_t mode)
201 {
202 struct inode *inode;
203
204 inode = ntfs_create_inode(mnt_userns, dir, dentry, NULL, S_IFDIR | mode,
205 0, NULL, 0, NULL);
206
207 return IS_ERR(inode) ? PTR_ERR(inode) : 0;
208 }
209
210 /*
211 * ntfs_rmdir - inode_operations::rm_dir
212 */
ntfs_rmdir(struct inode * dir,struct dentry * dentry)213 static int ntfs_rmdir(struct inode *dir, struct dentry *dentry)
214 {
215 struct ntfs_inode *ni = ntfs_i(dir);
216 int err;
217
218 ni_lock_dir(ni);
219
220 err = ntfs_unlink_inode(dir, dentry);
221
222 ni_unlock(ni);
223
224 return err;
225 }
226
227 /*
228 * ntfs_rename - inode_operations::rename
229 */
ntfs_rename(struct user_namespace * mnt_userns,struct inode * dir,struct dentry * dentry,struct inode * new_dir,struct dentry * new_dentry,u32 flags)230 static int ntfs_rename(struct user_namespace *mnt_userns, struct inode *dir,
231 struct dentry *dentry, struct inode *new_dir,
232 struct dentry *new_dentry, u32 flags)
233 {
234 int err;
235 struct super_block *sb = dir->i_sb;
236 struct ntfs_sb_info *sbi = sb->s_fs_info;
237 struct ntfs_inode *dir_ni = ntfs_i(dir);
238 struct ntfs_inode *new_dir_ni = ntfs_i(new_dir);
239 struct inode *inode = d_inode(dentry);
240 struct ntfs_inode *ni = ntfs_i(inode);
241 struct inode *new_inode = d_inode(new_dentry);
242 struct NTFS_DE *de, *new_de;
243 bool is_same, is_bad;
244 /*
245 * de - memory of PATH_MAX bytes:
246 * [0-1024) - original name (dentry->d_name)
247 * [1024-2048) - paired to original name, usually DOS variant of dentry->d_name
248 * [2048-3072) - new name (new_dentry->d_name)
249 */
250 static_assert(SIZEOF_ATTRIBUTE_FILENAME_MAX + SIZEOF_RESIDENT < 1024);
251 static_assert(SIZEOF_ATTRIBUTE_FILENAME_MAX + sizeof(struct NTFS_DE) <
252 1024);
253 static_assert(PATH_MAX >= 4 * 1024);
254
255 if (flags & ~RENAME_NOREPLACE)
256 return -EINVAL;
257
258 is_same = dentry->d_name.len == new_dentry->d_name.len &&
259 !memcmp(dentry->d_name.name, new_dentry->d_name.name,
260 dentry->d_name.len);
261
262 if (is_same && dir == new_dir) {
263 /* Nothing to do. */
264 return 0;
265 }
266
267 if (ntfs_is_meta_file(sbi, inode->i_ino)) {
268 /* Should we print an error? */
269 return -EINVAL;
270 }
271
272 if (new_inode) {
273 /* Target name exists. Unlink it. */
274 dget(new_dentry);
275 ni_lock_dir(new_dir_ni);
276 err = ntfs_unlink_inode(new_dir, new_dentry);
277 ni_unlock(new_dir_ni);
278 dput(new_dentry);
279 if (err)
280 return err;
281 }
282
283 /* Allocate PATH_MAX bytes. */
284 de = __getname();
285 if (!de)
286 return -ENOMEM;
287
288 /* Translate dentry->d_name into unicode form. */
289 err = fill_name_de(sbi, de, &dentry->d_name, NULL);
290 if (err < 0)
291 goto out;
292
293 if (is_same) {
294 /* Reuse 'de'. */
295 new_de = de;
296 } else {
297 /* Translate new_dentry->d_name into unicode form. */
298 new_de = Add2Ptr(de, 2048);
299 err = fill_name_de(sbi, new_de, &new_dentry->d_name, NULL);
300 if (err < 0)
301 goto out;
302 }
303
304 ni_lock_dir(dir_ni);
305 ni_lock(ni);
306
307 is_bad = false;
308 err = ni_rename(dir_ni, new_dir_ni, ni, de, new_de, &is_bad);
309 if (is_bad) {
310 /* Restore after failed rename failed too. */
311 make_bad_inode(inode);
312 ntfs_inode_err(inode, "failed to undo rename");
313 ntfs_set_state(sbi, NTFS_DIRTY_ERROR);
314 } else if (!err) {
315 inode->i_ctime = dir->i_ctime = dir->i_mtime =
316 current_time(dir);
317 mark_inode_dirty(inode);
318 mark_inode_dirty(dir);
319 if (dir != new_dir) {
320 new_dir->i_mtime = new_dir->i_ctime = dir->i_ctime;
321 mark_inode_dirty(new_dir);
322 }
323
324 if (IS_DIRSYNC(dir))
325 ntfs_sync_inode(dir);
326
327 if (IS_DIRSYNC(new_dir))
328 ntfs_sync_inode(inode);
329 }
330
331 ni_unlock(ni);
332 ni_unlock(dir_ni);
333 out:
334 __putname(de);
335 return err;
336 }
337
ntfs3_get_parent(struct dentry * child)338 struct dentry *ntfs3_get_parent(struct dentry *child)
339 {
340 struct inode *inode = d_inode(child);
341 struct ntfs_inode *ni = ntfs_i(inode);
342
343 struct ATTR_LIST_ENTRY *le = NULL;
344 struct ATTRIB *attr = NULL;
345 struct ATTR_FILE_NAME *fname;
346
347 while ((attr = ni_find_attr(ni, attr, &le, ATTR_NAME, NULL, 0, NULL,
348 NULL))) {
349 fname = resident_data_ex(attr, SIZEOF_ATTRIBUTE_FILENAME);
350 if (!fname)
351 continue;
352
353 return d_obtain_alias(
354 ntfs_iget5(inode->i_sb, &fname->home, NULL));
355 }
356
357 return ERR_PTR(-ENOENT);
358 }
359
360 // clang-format off
361 const struct inode_operations ntfs_dir_inode_operations = {
362 .lookup = ntfs_lookup,
363 .create = ntfs_create,
364 .link = ntfs_link,
365 .unlink = ntfs_unlink,
366 .symlink = ntfs_symlink,
367 .mkdir = ntfs_mkdir,
368 .rmdir = ntfs_rmdir,
369 .mknod = ntfs_mknod,
370 .rename = ntfs_rename,
371 .permission = ntfs_permission,
372 .get_acl = ntfs_get_acl,
373 .set_acl = ntfs_set_acl,
374 .setattr = ntfs3_setattr,
375 .getattr = ntfs_getattr,
376 .listxattr = ntfs_listxattr,
377 .fiemap = ntfs_fiemap,
378 };
379
380 const struct inode_operations ntfs_special_inode_operations = {
381 .setattr = ntfs3_setattr,
382 .getattr = ntfs_getattr,
383 .listxattr = ntfs_listxattr,
384 .get_acl = ntfs_get_acl,
385 .set_acl = ntfs_set_acl,
386 };
387 // clang-format on
388
