1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * acl.c
4 *
5 * Copyright (C) 2004, 2008 Oracle. All rights reserved.
6 *
7 * CREDITS:
8 * Lots of code in this file is copy from linux/fs/ext3/acl.c.
9 * Copyright (C) 2001-2003 Andreas Gruenbacher, <agruen@suse.de>
10 */
11
12 #include <linux/init.h>
13 #include <linux/module.h>
14 #include <linux/slab.h>
15 #include <linux/string.h>
16
17 #include <cluster/masklog.h>
18
19 #include "ocfs2.h"
20 #include "alloc.h"
21 #include "dlmglue.h"
22 #include "file.h"
23 #include "inode.h"
24 #include "journal.h"
25 #include "ocfs2_fs.h"
26
27 #include "xattr.h"
28 #include "acl.h"
29
30 /*
31 * Convert from xattr value to acl struct.
32 */
ocfs2_acl_from_xattr(const void * value,size_t size)33 static struct posix_acl *ocfs2_acl_from_xattr(const void *value, size_t size)
34 {
35 int n, count;
36 struct posix_acl *acl;
37
38 if (!value)
39 return NULL;
40 if (size < sizeof(struct posix_acl_entry))
41 return ERR_PTR(-EINVAL);
42
43 count = size / sizeof(struct posix_acl_entry);
44
45 acl = posix_acl_alloc(count, GFP_NOFS);
46 if (!acl)
47 return ERR_PTR(-ENOMEM);
48 for (n = 0; n < count; n++) {
49 struct ocfs2_acl_entry *entry =
50 (struct ocfs2_acl_entry *)value;
51
52 acl->a_entries[n].e_tag = le16_to_cpu(entry->e_tag);
53 acl->a_entries[n].e_perm = le16_to_cpu(entry->e_perm);
54 switch(acl->a_entries[n].e_tag) {
55 case ACL_USER:
56 acl->a_entries[n].e_uid =
57 make_kuid(&init_user_ns,
58 le32_to_cpu(entry->e_id));
59 break;
60 case ACL_GROUP:
61 acl->a_entries[n].e_gid =
62 make_kgid(&init_user_ns,
63 le32_to_cpu(entry->e_id));
64 break;
65 default:
66 break;
67 }
68 value += sizeof(struct posix_acl_entry);
69
70 }
71 return acl;
72 }
73
74 /*
75 * Convert acl struct to xattr value.
76 */
ocfs2_acl_to_xattr(const struct posix_acl * acl,size_t * size)77 static void *ocfs2_acl_to_xattr(const struct posix_acl *acl, size_t *size)
78 {
79 struct ocfs2_acl_entry *entry = NULL;
80 char *ocfs2_acl;
81 size_t n;
82
83 *size = acl->a_count * sizeof(struct posix_acl_entry);
84
85 ocfs2_acl = kmalloc(*size, GFP_NOFS);
86 if (!ocfs2_acl)
87 return ERR_PTR(-ENOMEM);
88
89 entry = (struct ocfs2_acl_entry *)ocfs2_acl;
90 for (n = 0; n < acl->a_count; n++, entry++) {
91 entry->e_tag = cpu_to_le16(acl->a_entries[n].e_tag);
92 entry->e_perm = cpu_to_le16(acl->a_entries[n].e_perm);
93 switch(acl->a_entries[n].e_tag) {
94 case ACL_USER:
95 entry->e_id = cpu_to_le32(
96 from_kuid(&init_user_ns,
97 acl->a_entries[n].e_uid));
98 break;
99 case ACL_GROUP:
100 entry->e_id = cpu_to_le32(
101 from_kgid(&init_user_ns,
102 acl->a_entries[n].e_gid));
103 break;
104 default:
105 entry->e_id = cpu_to_le32(ACL_UNDEFINED_ID);
106 break;
107 }
108 }
109 return ocfs2_acl;
110 }
111
ocfs2_get_acl_nolock(struct inode * inode,int type,struct buffer_head * di_bh)112 static struct posix_acl *ocfs2_get_acl_nolock(struct inode *inode,
113 int type,
114 struct buffer_head *di_bh)
115 {
116 int name_index;
117 char *value = NULL;
118 struct posix_acl *acl;
119 int retval;
120
121 switch (type) {
122 case ACL_TYPE_ACCESS:
123 name_index = OCFS2_XATTR_INDEX_POSIX_ACL_ACCESS;
124 break;
125 case ACL_TYPE_DEFAULT:
126 name_index = OCFS2_XATTR_INDEX_POSIX_ACL_DEFAULT;
127 break;
128 default:
129 return ERR_PTR(-EINVAL);
130 }
131
132 retval = ocfs2_xattr_get_nolock(inode, di_bh, name_index, "", NULL, 0);
133 if (retval > 0) {
134 value = kmalloc(retval, GFP_NOFS);
135 if (!value)
136 return ERR_PTR(-ENOMEM);
137 retval = ocfs2_xattr_get_nolock(inode, di_bh, name_index,
138 "", value, retval);
139 }
140
141 if (retval > 0)
142 acl = ocfs2_acl_from_xattr(value, retval);
143 else if (retval == -ENODATA || retval == 0)
144 acl = NULL;
145 else
146 acl = ERR_PTR(retval);
147
148 kfree(value);
149
150 return acl;
151 }
152
153 /*
154 * Helper function to set i_mode in memory and disk. Some call paths
155 * will not have di_bh or a journal handle to pass, in which case it
156 * will create it's own.
157 */
ocfs2_acl_set_mode(struct inode * inode,struct buffer_head * di_bh,handle_t * handle,umode_t new_mode)158 static int ocfs2_acl_set_mode(struct inode *inode, struct buffer_head *di_bh,
159 handle_t *handle, umode_t new_mode)
160 {
161 int ret, commit_handle = 0;
162 struct ocfs2_dinode *di;
163
164 if (di_bh == NULL) {
165 ret = ocfs2_read_inode_block(inode, &di_bh);
166 if (ret) {
167 mlog_errno(ret);
168 goto out;
169 }
170 } else
171 get_bh(di_bh);
172
173 if (handle == NULL) {
174 handle = ocfs2_start_trans(OCFS2_SB(inode->i_sb),
175 OCFS2_INODE_UPDATE_CREDITS);
176 if (IS_ERR(handle)) {
177 ret = PTR_ERR(handle);
178 mlog_errno(ret);
179 goto out_brelse;
180 }
181
182 commit_handle = 1;
183 }
184
185 di = (struct ocfs2_dinode *)di_bh->b_data;
186 ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
187 OCFS2_JOURNAL_ACCESS_WRITE);
188 if (ret) {
189 mlog_errno(ret);
190 goto out_commit;
191 }
192
193 inode->i_mode = new_mode;
194 inode->i_ctime = current_time(inode);
195 di->i_mode = cpu_to_le16(inode->i_mode);
196 di->i_ctime = cpu_to_le64(inode->i_ctime.tv_sec);
197 di->i_ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
198 ocfs2_update_inode_fsync_trans(handle, inode, 0);
199
200 ocfs2_journal_dirty(handle, di_bh);
201
202 out_commit:
203 if (commit_handle)
204 ocfs2_commit_trans(OCFS2_SB(inode->i_sb), handle);
205 out_brelse:
206 brelse(di_bh);
207 out:
208 return ret;
209 }
210
211 /*
212 * Set the access or default ACL of an inode.
213 */
ocfs2_set_acl(handle_t * handle,struct inode * inode,struct buffer_head * di_bh,int type,struct posix_acl * acl,struct ocfs2_alloc_context * meta_ac,struct ocfs2_alloc_context * data_ac)214 static int ocfs2_set_acl(handle_t *handle,
215 struct inode *inode,
216 struct buffer_head *di_bh,
217 int type,
218 struct posix_acl *acl,
219 struct ocfs2_alloc_context *meta_ac,
220 struct ocfs2_alloc_context *data_ac)
221 {
222 int name_index;
223 void *value = NULL;
224 size_t size = 0;
225 int ret;
226
227 if (S_ISLNK(inode->i_mode))
228 return -EOPNOTSUPP;
229
230 switch (type) {
231 case ACL_TYPE_ACCESS:
232 name_index = OCFS2_XATTR_INDEX_POSIX_ACL_ACCESS;
233 break;
234 case ACL_TYPE_DEFAULT:
235 name_index = OCFS2_XATTR_INDEX_POSIX_ACL_DEFAULT;
236 if (!S_ISDIR(inode->i_mode))
237 return acl ? -EACCES : 0;
238 break;
239 default:
240 return -EINVAL;
241 }
242
243 if (acl) {
244 value = ocfs2_acl_to_xattr(acl, &size);
245 if (IS_ERR(value))
246 return (int)PTR_ERR(value);
247 }
248
249 if (handle)
250 ret = ocfs2_xattr_set_handle(handle, inode, di_bh, name_index,
251 "", value, size, 0,
252 meta_ac, data_ac);
253 else
254 ret = ocfs2_xattr_set(inode, name_index, "", value, size, 0);
255
256 kfree(value);
257 if (!ret)
258 set_cached_acl(inode, type, acl);
259
260 return ret;
261 }
262
ocfs2_iop_set_acl(struct user_namespace * mnt_userns,struct inode * inode,struct posix_acl * acl,int type)263 int ocfs2_iop_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
264 struct posix_acl *acl, int type)
265 {
266 struct buffer_head *bh = NULL;
267 int status, had_lock;
268 struct ocfs2_lock_holder oh;
269
270 had_lock = ocfs2_inode_lock_tracker(inode, &bh, 1, &oh);
271 if (had_lock < 0)
272 return had_lock;
273 if (type == ACL_TYPE_ACCESS && acl) {
274 umode_t mode;
275
276 status = posix_acl_update_mode(&init_user_ns, inode, &mode,
277 &acl);
278 if (status)
279 goto unlock;
280
281 status = ocfs2_acl_set_mode(inode, bh, NULL, mode);
282 if (status)
283 goto unlock;
284 }
285 status = ocfs2_set_acl(NULL, inode, bh, type, acl, NULL, NULL);
286 unlock:
287 ocfs2_inode_unlock_tracker(inode, 1, &oh, had_lock);
288 brelse(bh);
289 return status;
290 }
291
ocfs2_iop_get_acl(struct inode * inode,int type,bool rcu)292 struct posix_acl *ocfs2_iop_get_acl(struct inode *inode, int type, bool rcu)
293 {
294 struct ocfs2_super *osb;
295 struct buffer_head *di_bh = NULL;
296 struct posix_acl *acl;
297 int had_lock;
298 struct ocfs2_lock_holder oh;
299
300 if (rcu)
301 return ERR_PTR(-ECHILD);
302
303 osb = OCFS2_SB(inode->i_sb);
304 if (!(osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL))
305 return NULL;
306
307 had_lock = ocfs2_inode_lock_tracker(inode, &di_bh, 0, &oh);
308 if (had_lock < 0)
309 return ERR_PTR(had_lock);
310
311 down_read(&OCFS2_I(inode)->ip_xattr_sem);
312 acl = ocfs2_get_acl_nolock(inode, type, di_bh);
313 up_read(&OCFS2_I(inode)->ip_xattr_sem);
314
315 ocfs2_inode_unlock_tracker(inode, 0, &oh, had_lock);
316 brelse(di_bh);
317 return acl;
318 }
319
ocfs2_acl_chmod(struct inode * inode,struct buffer_head * bh)320 int ocfs2_acl_chmod(struct inode *inode, struct buffer_head *bh)
321 {
322 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
323 struct posix_acl *acl;
324 int ret;
325
326 if (S_ISLNK(inode->i_mode))
327 return -EOPNOTSUPP;
328
329 if (!(osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL))
330 return 0;
331
332 down_read(&OCFS2_I(inode)->ip_xattr_sem);
333 acl = ocfs2_get_acl_nolock(inode, ACL_TYPE_ACCESS, bh);
334 up_read(&OCFS2_I(inode)->ip_xattr_sem);
335 if (IS_ERR_OR_NULL(acl))
336 return PTR_ERR_OR_ZERO(acl);
337 ret = __posix_acl_chmod(&acl, GFP_KERNEL, inode->i_mode);
338 if (ret)
339 return ret;
340 ret = ocfs2_set_acl(NULL, inode, NULL, ACL_TYPE_ACCESS,
341 acl, NULL, NULL);
342 posix_acl_release(acl);
343 return ret;
344 }
345
346 /*
347 * Initialize the ACLs of a new inode. If parent directory has default ACL,
348 * then clone to new inode. Called from ocfs2_mknod.
349 */
ocfs2_init_acl(handle_t * handle,struct inode * inode,struct inode * dir,struct buffer_head * di_bh,struct buffer_head * dir_bh,struct ocfs2_alloc_context * meta_ac,struct ocfs2_alloc_context * data_ac)350 int ocfs2_init_acl(handle_t *handle,
351 struct inode *inode,
352 struct inode *dir,
353 struct buffer_head *di_bh,
354 struct buffer_head *dir_bh,
355 struct ocfs2_alloc_context *meta_ac,
356 struct ocfs2_alloc_context *data_ac)
357 {
358 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
359 struct posix_acl *acl = NULL;
360 int ret = 0, ret2;
361 umode_t mode;
362
363 if (!S_ISLNK(inode->i_mode)) {
364 if (osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL) {
365 down_read(&OCFS2_I(dir)->ip_xattr_sem);
366 acl = ocfs2_get_acl_nolock(dir, ACL_TYPE_DEFAULT,
367 dir_bh);
368 up_read(&OCFS2_I(dir)->ip_xattr_sem);
369 if (IS_ERR(acl))
370 return PTR_ERR(acl);
371 }
372 if (!acl) {
373 mode = inode->i_mode & ~current_umask();
374 ret = ocfs2_acl_set_mode(inode, di_bh, handle, mode);
375 if (ret) {
376 mlog_errno(ret);
377 goto cleanup;
378 }
379 }
380 }
381 if ((osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL) && acl) {
382 if (S_ISDIR(inode->i_mode)) {
383 ret = ocfs2_set_acl(handle, inode, di_bh,
384 ACL_TYPE_DEFAULT, acl,
385 meta_ac, data_ac);
386 if (ret)
387 goto cleanup;
388 }
389 mode = inode->i_mode;
390 ret = __posix_acl_create(&acl, GFP_NOFS, &mode);
391 if (ret < 0)
392 return ret;
393
394 ret2 = ocfs2_acl_set_mode(inode, di_bh, handle, mode);
395 if (ret2) {
396 mlog_errno(ret2);
397 ret = ret2;
398 goto cleanup;
399 }
400 if (ret > 0) {
401 ret = ocfs2_set_acl(handle, inode,
402 di_bh, ACL_TYPE_ACCESS,
403 acl, meta_ac, data_ac);
404 }
405 }
406 cleanup:
407 posix_acl_release(acl);
408 return ret;
409 }
410