Merge branch 'stable-4.10' of git://git.infradead.org/users/pcmoore/audit
[linux-2.6-block.git] / fs / reiserfs / xattr_acl.c
CommitLineData
16f7e0fe 1#include <linux/capability.h>
1da177e4
LT
2#include <linux/fs.h>
3#include <linux/posix_acl.h>
f466c6fd 4#include "reiserfs.h"
1da177e4
LT
5#include <linux/errno.h>
6#include <linux/pagemap.h>
7#include <linux/xattr.h>
5a0e3ad6 8#include <linux/slab.h>
9a59f452 9#include <linux/posix_acl_xattr.h>
c45ac888 10#include "xattr.h"
a3063ab8 11#include "acl.h"
17093991 12#include <linux/uaccess.h>
1da177e4 13
47f70d08 14static int __reiserfs_set_acl(struct reiserfs_transaction_handle *th,
0ab2621e 15 struct inode *inode, int type,
bd4c625c 16 struct posix_acl *acl);
1da177e4 17
47f70d08
CH
18
19int
20reiserfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
1da177e4 21{
0ab2621e
JM
22 int error, error2;
23 struct reiserfs_transaction_handle th;
24 size_t jcreate_blocks;
47f70d08
CH
25 int size = acl ? posix_acl_xattr_size(acl->a_count) : 0;
26
1da177e4 27
098297b2
JM
28 /*
29 * Pessimism: We can't assume that anything from the xattr root up
30 * has been created.
31 */
0ab2621e
JM
32
33 jcreate_blocks = reiserfs_xattr_jcreate_nblocks(inode) +
34 reiserfs_xattr_nblocks(inode, size) * 2;
35
36 reiserfs_write_lock(inode->i_sb);
37 error = journal_begin(&th, inode->i_sb, jcreate_blocks);
4c05141d 38 reiserfs_write_unlock(inode->i_sb);
0ab2621e 39 if (error == 0) {
47f70d08 40 error = __reiserfs_set_acl(&th, inode, type, acl);
4c05141d 41 reiserfs_write_lock(inode->i_sb);
58d85426 42 error2 = journal_end(&th);
4c05141d 43 reiserfs_write_unlock(inode->i_sb);
0ab2621e
JM
44 if (error2)
45 error = error2;
46 }
1da177e4 47
1da177e4
LT
48 return error;
49}
50
1da177e4
LT
51/*
52 * Convert from filesystem to in-memory representation.
53 */
9dad943a 54static struct posix_acl *reiserfs_posix_acl_from_disk(const void *value, size_t size)
1da177e4
LT
55{
56 const char *end = (char *)value + size;
57 int n, count;
58 struct posix_acl *acl;
59
60 if (!value)
61 return NULL;
62 if (size < sizeof(reiserfs_acl_header))
bd4c625c
LT
63 return ERR_PTR(-EINVAL);
64 if (((reiserfs_acl_header *) value)->a_version !=
1da177e4
LT
65 cpu_to_le32(REISERFS_ACL_VERSION))
66 return ERR_PTR(-EINVAL);
67 value = (char *)value + sizeof(reiserfs_acl_header);
68 count = reiserfs_acl_count(size);
69 if (count < 0)
70 return ERR_PTR(-EINVAL);
71 if (count == 0)
72 return NULL;
73 acl = posix_acl_alloc(count, GFP_NOFS);
74 if (!acl)
75 return ERR_PTR(-ENOMEM);
bd4c625c
LT
76 for (n = 0; n < count; n++) {
77 reiserfs_acl_entry *entry = (reiserfs_acl_entry *) value;
1da177e4
LT
78 if ((char *)value + sizeof(reiserfs_acl_entry_short) > end)
79 goto fail;
bd4c625c 80 acl->a_entries[n].e_tag = le16_to_cpu(entry->e_tag);
1da177e4 81 acl->a_entries[n].e_perm = le16_to_cpu(entry->e_perm);
bd4c625c
LT
82 switch (acl->a_entries[n].e_tag) {
83 case ACL_USER_OBJ:
84 case ACL_GROUP_OBJ:
85 case ACL_MASK:
86 case ACL_OTHER:
87 value = (char *)value +
88 sizeof(reiserfs_acl_entry_short);
bd4c625c
LT
89 break;
90
91 case ACL_USER:
df814654
EB
92 value = (char *)value + sizeof(reiserfs_acl_entry);
93 if ((char *)value > end)
94 goto fail;
95 acl->a_entries[n].e_uid =
96 make_kuid(&init_user_ns,
97 le32_to_cpu(entry->e_id));
98 break;
bd4c625c
LT
99 case ACL_GROUP:
100 value = (char *)value + sizeof(reiserfs_acl_entry);
101 if ((char *)value > end)
1da177e4 102 goto fail;
df814654
EB
103 acl->a_entries[n].e_gid =
104 make_kgid(&init_user_ns,
105 le32_to_cpu(entry->e_id));
bd4c625c
LT
106 break;
107
108 default:
109 goto fail;
1da177e4
LT
110 }
111 }
112 if (value != end)
113 goto fail;
114 return acl;
115
cf776a7a 116fail:
1da177e4
LT
117 posix_acl_release(acl);
118 return ERR_PTR(-EINVAL);
119}
120
121/*
122 * Convert from in-memory to filesystem representation.
123 */
9dad943a 124static void *reiserfs_posix_acl_to_disk(const struct posix_acl *acl, size_t * size)
1da177e4
LT
125{
126 reiserfs_acl_header *ext_acl;
127 char *e;
128 int n;
129
130 *size = reiserfs_acl_size(acl->a_count);
5cbded58 131 ext_acl = kmalloc(sizeof(reiserfs_acl_header) +
bd4c625c
LT
132 acl->a_count *
133 sizeof(reiserfs_acl_entry),
134 GFP_NOFS);
1da177e4
LT
135 if (!ext_acl)
136 return ERR_PTR(-ENOMEM);
137 ext_acl->a_version = cpu_to_le32(REISERFS_ACL_VERSION);
138 e = (char *)ext_acl + sizeof(reiserfs_acl_header);
bd4c625c 139 for (n = 0; n < acl->a_count; n++) {
df814654 140 const struct posix_acl_entry *acl_e = &acl->a_entries[n];
bd4c625c
LT
141 reiserfs_acl_entry *entry = (reiserfs_acl_entry *) e;
142 entry->e_tag = cpu_to_le16(acl->a_entries[n].e_tag);
1da177e4 143 entry->e_perm = cpu_to_le16(acl->a_entries[n].e_perm);
bd4c625c
LT
144 switch (acl->a_entries[n].e_tag) {
145 case ACL_USER:
df814654
EB
146 entry->e_id = cpu_to_le32(
147 from_kuid(&init_user_ns, acl_e->e_uid));
148 e += sizeof(reiserfs_acl_entry);
149 break;
bd4c625c 150 case ACL_GROUP:
df814654
EB
151 entry->e_id = cpu_to_le32(
152 from_kgid(&init_user_ns, acl_e->e_gid));
bd4c625c
LT
153 e += sizeof(reiserfs_acl_entry);
154 break;
155
156 case ACL_USER_OBJ:
157 case ACL_GROUP_OBJ:
158 case ACL_MASK:
159 case ACL_OTHER:
160 e += sizeof(reiserfs_acl_entry_short);
161 break;
162
163 default:
164 goto fail;
1da177e4
LT
165 }
166 }
167 return (char *)ext_acl;
168
cf776a7a 169fail:
1da177e4
LT
170 kfree(ext_acl);
171 return ERR_PTR(-EINVAL);
172}
173
174/*
175 * Inode operation get_posix_acl().
176 *
1b1dcc1b 177 * inode->i_mutex: down
1da177e4
LT
178 * BKL held [before 2.5.x]
179 */
bd4c625c 180struct posix_acl *reiserfs_get_acl(struct inode *inode, int type)
1da177e4
LT
181{
182 char *name, *value;
073aaa1b 183 struct posix_acl *acl;
3cdc409c 184 int size;
1da177e4 185 int retval;
bd4c625c
LT
186
187 switch (type) {
188 case ACL_TYPE_ACCESS:
97d79299 189 name = XATTR_NAME_POSIX_ACL_ACCESS;
bd4c625c
LT
190 break;
191 case ACL_TYPE_DEFAULT:
97d79299 192 name = XATTR_NAME_POSIX_ACL_DEFAULT;
bd4c625c
LT
193 break;
194 default:
073aaa1b 195 BUG();
bd4c625c
LT
196 }
197
bd4c625c 198 size = reiserfs_xattr_get(inode, name, NULL, 0);
3cdc409c 199 if (size < 0) {
b8a7a3a6 200 if (size == -ENODATA || size == -ENOSYS)
bd4c625c 201 return NULL;
bd4c625c
LT
202 return ERR_PTR(size);
203 }
1da177e4 204
bd4c625c
LT
205 value = kmalloc(size, GFP_NOFS);
206 if (!value)
207 return ERR_PTR(-ENOMEM);
1da177e4
LT
208
209 retval = reiserfs_xattr_get(inode, name, value, size);
210 if (retval == -ENODATA || retval == -ENOSYS) {
098297b2
JM
211 /*
212 * This shouldn't actually happen as it should have
213 * been caught above.. but just in case
214 */
1da177e4 215 acl = NULL;
bd4c625c 216 } else if (retval < 0) {
1da177e4
LT
217 acl = ERR_PTR(retval);
218 } else {
9dad943a 219 acl = reiserfs_posix_acl_from_disk(value, retval);
bd4c625c 220 }
1da177e4
LT
221
222 kfree(value);
223 return acl;
224}
225
226/*
227 * Inode operation set_posix_acl().
228 *
1b1dcc1b 229 * inode->i_mutex: down
1da177e4
LT
230 * BKL held [before 2.5.x]
231 */
232static int
47f70d08 233__reiserfs_set_acl(struct reiserfs_transaction_handle *th, struct inode *inode,
0ab2621e 234 int type, struct posix_acl *acl)
1da177e4 235{
bd4c625c 236 char *name;
1da177e4 237 void *value = NULL;
48b32a35 238 size_t size = 0;
1da177e4 239 int error;
1da177e4 240
bd4c625c
LT
241 switch (type) {
242 case ACL_TYPE_ACCESS:
97d79299 243 name = XATTR_NAME_POSIX_ACL_ACCESS;
bd4c625c 244 if (acl) {
07393101
JK
245 error = posix_acl_update_mode(inode, &inode->i_mode, &acl);
246 if (error)
bd4c625c 247 return error;
bd4c625c
LT
248 }
249 break;
250 case ACL_TYPE_DEFAULT:
97d79299 251 name = XATTR_NAME_POSIX_ACL_DEFAULT;
bd4c625c
LT
252 if (!S_ISDIR(inode->i_mode))
253 return acl ? -EACCES : 0;
254 break;
255 default:
256 return -EINVAL;
257 }
258
259 if (acl) {
9dad943a 260 value = reiserfs_posix_acl_to_disk(acl, &size);
bd4c625c
LT
261 if (IS_ERR(value))
262 return (int)PTR_ERR(value);
48b32a35
JM
263 }
264
0ab2621e 265 error = reiserfs_xattr_set_handle(th, inode, name, value, size, 0);
48b32a35
JM
266
267 /*
268 * Ensure that the inode gets dirtied if we're only using
269 * the mode bits and an old ACL didn't exist. We don't need
270 * to check if the inode is hashed here since we won't get
271 * called by reiserfs_inherit_default_acl().
272 */
273 if (error == -ENODATA) {
274 error = 0;
275 if (type == ACL_TYPE_ACCESS) {
02027d42 276 inode->i_ctime = current_time(inode);
bd4c625c 277 mark_inode_dirty(inode);
bd4c625c
LT
278 }
279 }
1da177e4 280
833d304b 281 kfree(value);
1da177e4 282
d984561b 283 if (!error)
073aaa1b 284 set_cached_acl(inode, type, acl);
1da177e4
LT
285
286 return error;
287}
288
098297b2
JM
289/*
290 * dir->i_mutex: locked,
291 * inode is new and not released into the wild yet
292 */
1da177e4 293int
0ab2621e
JM
294reiserfs_inherit_default_acl(struct reiserfs_transaction_handle *th,
295 struct inode *dir, struct dentry *dentry,
bd4c625c 296 struct inode *inode)
1da177e4 297{
47f70d08 298 struct posix_acl *default_acl, *acl;
bd4c625c
LT
299 int err = 0;
300
301 /* ACLs only get applied to files and directories */
302 if (S_ISLNK(inode->i_mode))
303 return 0;
304
098297b2
JM
305 /*
306 * ACLs can only be used on "new" objects, so if it's an old object
307 * there is nothing to inherit from
308 */
bd4c625c
LT
309 if (get_inode_sd_version(dir) == STAT_DATA_V1)
310 goto apply_umask;
311
098297b2
JM
312 /*
313 * Don't apply ACLs to objects in the .reiserfs_priv tree.. This
bd4c625c 314 * would be useless since permissions are ignored, and a pain because
098297b2
JM
315 * it introduces locking cycles
316 */
6dfede69
JM
317 if (IS_PRIVATE(dir)) {
318 inode->i_flags |= S_PRIVATE;
bd4c625c
LT
319 goto apply_umask;
320 }
321
47f70d08
CH
322 err = posix_acl_create(dir, &inode->i_mode, &default_acl, &acl);
323 if (err)
324 return err;
bd4c625c 325
47f70d08
CH
326 if (default_acl) {
327 err = __reiserfs_set_acl(th, inode, ACL_TYPE_DEFAULT,
328 default_acl);
329 posix_acl_release(default_acl);
330 }
bd4c625c 331 if (acl) {
47f70d08
CH
332 if (!err)
333 err = __reiserfs_set_acl(th, inode, ACL_TYPE_ACCESS,
334 acl);
bd4c625c 335 posix_acl_release(acl);
bd4c625c
LT
336 }
337
338 return err;
47f70d08 339
cf776a7a 340apply_umask:
47f70d08
CH
341 /* no ACL, apply umask */
342 inode->i_mode &= ~current_umask();
343 return err;
1da177e4
LT
344}
345
0ab2621e
JM
346/* This is used to cache the default acl before a new object is created.
347 * The biggest reason for this is to get an idea of how many blocks will
348 * actually be required for the create operation if we must inherit an ACL.
349 * An ACL write can add up to 3 object creations and an additional file write
350 * so we'd prefer not to reserve that many blocks in the journal if we can.
351 * It also has the advantage of not loading the ACL with a transaction open,
352 * this may seem silly, but if the owner of the directory is doing the
353 * creation, the ACL may not be loaded since the permissions wouldn't require
354 * it.
355 * We return the number of blocks required for the transaction.
356 */
bd4c625c 357int reiserfs_cache_default_acl(struct inode *inode)
1da177e4 358{
0ab2621e
JM
359 struct posix_acl *acl;
360 int nblocks = 0;
361
362 if (IS_PRIVATE(inode))
363 return 0;
364
7dffc87f 365 acl = get_acl(inode, ACL_TYPE_DEFAULT);
0ab2621e
JM
366
367 if (acl && !IS_ERR(acl)) {
368 int size = reiserfs_acl_size(acl->a_count);
369
370 /* Other xattrs can be created during inode creation. We don't
371 * want to claim too many blocks, so we check to see if we
372 * we need to create the tree to the xattrs, and then we
373 * just want two files. */
374 nblocks = reiserfs_xattr_jcreate_nblocks(inode);
375 nblocks += JOURNAL_BLOCKS_PER_OBJECT(inode->i_sb);
376
377 REISERFS_I(inode)->i_flags |= i_has_xattr_dir;
378
379 /* We need to account for writes + bitmaps for two files */
380 nblocks += reiserfs_xattr_nblocks(inode, size) * 4;
381 posix_acl_release(acl);
bd4c625c
LT
382 }
383
0ab2621e 384 return nblocks;
1da177e4
LT
385}
386
4c05141d
JM
387/*
388 * Called under i_mutex
389 */
bd4c625c 390int reiserfs_acl_chmod(struct inode *inode)
1da177e4 391{
4a857011
JM
392 if (IS_PRIVATE(inode))
393 return 0;
bd4c625c 394 if (get_inode_sd_version(inode) == STAT_DATA_V1 ||
47f70d08 395 !reiserfs_posixacl(inode->i_sb))
bd4c625c 396 return 0;
1da177e4 397
47f70d08 398 return posix_acl_chmod(inode, inode->i_mode);
1da177e4 399}