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_set_ctime_current(inode);
195 di->i_mode = cpu_to_le16(inode->i_mode);
196 di->i_ctime = cpu_to_le64(inode_get_ctime_sec(inode));
197 di->i_ctime_nsec = cpu_to_le32(inode_get_ctime_nsec(inode));
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 mnt_idmap * idmap,struct dentry * dentry,struct posix_acl * acl,int type)263 int ocfs2_iop_set_acl(struct mnt_idmap *idmap, struct dentry *dentry,
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 struct inode *inode = d_inode(dentry);
270
271 had_lock = ocfs2_inode_lock_tracker(inode, &bh, 1, &oh);
272 if (had_lock < 0)
273 return had_lock;
274 if (type == ACL_TYPE_ACCESS && acl) {
275 umode_t mode;
276
277 status = posix_acl_update_mode(&nop_mnt_idmap, inode, &mode,
278 &acl);
279 if (status)
280 goto unlock;
281
282 status = ocfs2_acl_set_mode(inode, bh, NULL, mode);
283 if (status)
284 goto unlock;
285 }
286 status = ocfs2_set_acl(NULL, inode, bh, type, acl, NULL, NULL);
287 unlock:
288 ocfs2_inode_unlock_tracker(inode, 1, &oh, had_lock);
289 brelse(bh);
290 return status;
291 }
292
ocfs2_iop_get_acl(struct inode * inode,int type,bool rcu)293 struct posix_acl *ocfs2_iop_get_acl(struct inode *inode, int type, bool rcu)
294 {
295 struct ocfs2_super *osb;
296 struct buffer_head *di_bh = NULL;
297 struct posix_acl *acl;
298 int had_lock;
299 struct ocfs2_lock_holder oh;
300
301 if (rcu)
302 return ERR_PTR(-ECHILD);
303
304 osb = OCFS2_SB(inode->i_sb);
305 if (!(osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL))
306 return NULL;
307
308 had_lock = ocfs2_inode_lock_tracker(inode, &di_bh, 0, &oh);
309 if (had_lock < 0)
310 return ERR_PTR(had_lock);
311
312 down_read(&OCFS2_I(inode)->ip_xattr_sem);
313 acl = ocfs2_get_acl_nolock(inode, type, di_bh);
314 up_read(&OCFS2_I(inode)->ip_xattr_sem);
315
316 ocfs2_inode_unlock_tracker(inode, 0, &oh, had_lock);
317 brelse(di_bh);
318 return acl;
319 }
320
ocfs2_acl_chmod(struct inode * inode,struct buffer_head * bh)321 int ocfs2_acl_chmod(struct inode *inode, struct buffer_head *bh)
322 {
323 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
324 struct posix_acl *acl;
325 int ret;
326
327 if (S_ISLNK(inode->i_mode))
328 return -EOPNOTSUPP;
329
330 if (!(osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL))
331 return 0;
332
333 down_read(&OCFS2_I(inode)->ip_xattr_sem);
334 acl = ocfs2_get_acl_nolock(inode, ACL_TYPE_ACCESS, bh);
335 up_read(&OCFS2_I(inode)->ip_xattr_sem);
336 if (IS_ERR_OR_NULL(acl))
337 return PTR_ERR_OR_ZERO(acl);
338 ret = __posix_acl_chmod(&acl, GFP_KERNEL, inode->i_mode);
339 if (ret)
340 return ret;
341 ret = ocfs2_set_acl(NULL, inode, NULL, ACL_TYPE_ACCESS,
342 acl, NULL, NULL);
343 posix_acl_release(acl);
344 return ret;
345 }
346
347 /*
348 * Initialize the ACLs of a new inode. If parent directory has default ACL,
349 * then clone to new inode. Called from ocfs2_mknod.
350 */
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)351 int ocfs2_init_acl(handle_t *handle,
352 struct inode *inode,
353 struct inode *dir,
354 struct buffer_head *di_bh,
355 struct buffer_head *dir_bh,
356 struct ocfs2_alloc_context *meta_ac,
357 struct ocfs2_alloc_context *data_ac)
358 {
359 struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
360 struct posix_acl *acl = NULL;
361 int ret = 0, ret2;
362 umode_t mode;
363
364 if (!S_ISLNK(inode->i_mode)) {
365 if (osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL) {
366 down_read(&OCFS2_I(dir)->ip_xattr_sem);
367 acl = ocfs2_get_acl_nolock(dir, ACL_TYPE_DEFAULT,
368 dir_bh);
369 up_read(&OCFS2_I(dir)->ip_xattr_sem);
370 if (IS_ERR(acl))
371 return PTR_ERR(acl);
372 }
373 if (!acl) {
374 mode = inode->i_mode & ~current_umask();
375 ret = ocfs2_acl_set_mode(inode, di_bh, handle, mode);
376 if (ret) {
377 mlog_errno(ret);
378 goto cleanup;
379 }
380 }
381 }
382 if ((osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL) && acl) {
383 if (S_ISDIR(inode->i_mode)) {
384 ret = ocfs2_set_acl(handle, inode, di_bh,
385 ACL_TYPE_DEFAULT, acl,
386 meta_ac, data_ac);
387 if (ret)
388 goto cleanup;
389 }
390 mode = inode->i_mode;
391 ret = __posix_acl_create(&acl, GFP_NOFS, &mode);
392 if (ret < 0)
393 return ret;
394
395 ret2 = ocfs2_acl_set_mode(inode, di_bh, handle, mode);
396 if (ret2) {
397 mlog_errno(ret2);
398 ret = ret2;
399 goto cleanup;
400 }
401 if (ret > 0) {
402 ret = ocfs2_set_acl(handle, inode,
403 di_bh, ACL_TYPE_ACCESS,
404 acl, meta_ac, data_ac);
405 }
406 }
407 cleanup:
408 posix_acl_release(acl);
409 return ret;
410 }
411