1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/capability.h>
4 #include <linux/posix_acl.h>
6 #include <linux/errno.h>
7 #include <linux/pagemap.h>
8 #include <linux/xattr.h>
9 #include <linux/slab.h>
10 #include <linux/posix_acl_xattr.h>
13 #include <linux/uaccess.h>
15 static int __reiserfs_set_acl(struct reiserfs_transaction_handle
*th
,
16 struct inode
*inode
, int type
,
17 struct posix_acl
*acl
);
21 reiserfs_set_acl(struct user_namespace
*mnt_userns
, struct inode
*inode
,
22 struct posix_acl
*acl
, int type
)
25 struct reiserfs_transaction_handle th
;
26 size_t jcreate_blocks
;
27 int size
= acl
? posix_acl_xattr_size(acl
->a_count
) : 0;
29 umode_t mode
= inode
->i_mode
;
32 * Pessimism: We can't assume that anything from the xattr root up
36 jcreate_blocks
= reiserfs_xattr_jcreate_nblocks(inode
) +
37 reiserfs_xattr_nblocks(inode
, size
) * 2;
39 reiserfs_write_lock(inode
->i_sb
);
40 error
= journal_begin(&th
, inode
->i_sb
, jcreate_blocks
);
41 reiserfs_write_unlock(inode
->i_sb
);
43 if (type
== ACL_TYPE_ACCESS
&& acl
) {
44 error
= posix_acl_update_mode(&init_user_ns
, inode
,
50 error
= __reiserfs_set_acl(&th
, inode
, type
, acl
);
51 if (!error
&& update_mode
)
54 reiserfs_write_lock(inode
->i_sb
);
55 error2
= journal_end(&th
);
56 reiserfs_write_unlock(inode
->i_sb
);
65 * Convert from filesystem to in-memory representation.
67 static struct posix_acl
*reiserfs_posix_acl_from_disk(const void *value
, size_t size
)
69 const char *end
= (char *)value
+ size
;
71 struct posix_acl
*acl
;
75 if (size
< sizeof(reiserfs_acl_header
))
76 return ERR_PTR(-EINVAL
);
77 if (((reiserfs_acl_header
*) value
)->a_version
!=
78 cpu_to_le32(REISERFS_ACL_VERSION
))
79 return ERR_PTR(-EINVAL
);
80 value
= (char *)value
+ sizeof(reiserfs_acl_header
);
81 count
= reiserfs_acl_count(size
);
83 return ERR_PTR(-EINVAL
);
86 acl
= posix_acl_alloc(count
, GFP_NOFS
);
88 return ERR_PTR(-ENOMEM
);
89 for (n
= 0; n
< count
; n
++) {
90 reiserfs_acl_entry
*entry
= (reiserfs_acl_entry
*) value
;
91 if ((char *)value
+ sizeof(reiserfs_acl_entry_short
) > end
)
93 acl
->a_entries
[n
].e_tag
= le16_to_cpu(entry
->e_tag
);
94 acl
->a_entries
[n
].e_perm
= le16_to_cpu(entry
->e_perm
);
95 switch (acl
->a_entries
[n
].e_tag
) {
100 value
= (char *)value
+
101 sizeof(reiserfs_acl_entry_short
);
105 value
= (char *)value
+ sizeof(reiserfs_acl_entry
);
106 if ((char *)value
> end
)
108 acl
->a_entries
[n
].e_uid
=
109 make_kuid(&init_user_ns
,
110 le32_to_cpu(entry
->e_id
));
113 value
= (char *)value
+ sizeof(reiserfs_acl_entry
);
114 if ((char *)value
> end
)
116 acl
->a_entries
[n
].e_gid
=
117 make_kgid(&init_user_ns
,
118 le32_to_cpu(entry
->e_id
));
130 posix_acl_release(acl
);
131 return ERR_PTR(-EINVAL
);
135 * Convert from in-memory to filesystem representation.
137 static void *reiserfs_posix_acl_to_disk(const struct posix_acl
*acl
, size_t * size
)
139 reiserfs_acl_header
*ext_acl
;
143 *size
= reiserfs_acl_size(acl
->a_count
);
144 ext_acl
= kmalloc(sizeof(reiserfs_acl_header
) +
146 sizeof(reiserfs_acl_entry
),
149 return ERR_PTR(-ENOMEM
);
150 ext_acl
->a_version
= cpu_to_le32(REISERFS_ACL_VERSION
);
151 e
= (char *)ext_acl
+ sizeof(reiserfs_acl_header
);
152 for (n
= 0; n
< acl
->a_count
; n
++) {
153 const struct posix_acl_entry
*acl_e
= &acl
->a_entries
[n
];
154 reiserfs_acl_entry
*entry
= (reiserfs_acl_entry
*) e
;
155 entry
->e_tag
= cpu_to_le16(acl
->a_entries
[n
].e_tag
);
156 entry
->e_perm
= cpu_to_le16(acl
->a_entries
[n
].e_perm
);
157 switch (acl
->a_entries
[n
].e_tag
) {
159 entry
->e_id
= cpu_to_le32(
160 from_kuid(&init_user_ns
, acl_e
->e_uid
));
161 e
+= sizeof(reiserfs_acl_entry
);
164 entry
->e_id
= cpu_to_le32(
165 from_kgid(&init_user_ns
, acl_e
->e_gid
));
166 e
+= sizeof(reiserfs_acl_entry
);
173 e
+= sizeof(reiserfs_acl_entry_short
);
180 return (char *)ext_acl
;
184 return ERR_PTR(-EINVAL
);
188 * Inode operation get_posix_acl().
190 * inode->i_mutex: down
191 * BKL held [before 2.5.x]
193 struct posix_acl
*reiserfs_get_acl(struct inode
*inode
, int type
)
196 struct posix_acl
*acl
;
201 case ACL_TYPE_ACCESS
:
202 name
= XATTR_NAME_POSIX_ACL_ACCESS
;
204 case ACL_TYPE_DEFAULT
:
205 name
= XATTR_NAME_POSIX_ACL_DEFAULT
;
211 size
= reiserfs_xattr_get(inode
, name
, NULL
, 0);
213 if (size
== -ENODATA
|| size
== -ENOSYS
)
215 return ERR_PTR(size
);
218 value
= kmalloc(size
, GFP_NOFS
);
220 return ERR_PTR(-ENOMEM
);
222 retval
= reiserfs_xattr_get(inode
, name
, value
, size
);
223 if (retval
== -ENODATA
|| retval
== -ENOSYS
) {
225 * This shouldn't actually happen as it should have
226 * been caught above.. but just in case
229 } else if (retval
< 0) {
230 acl
= ERR_PTR(retval
);
232 acl
= reiserfs_posix_acl_from_disk(value
, retval
);
240 * Inode operation set_posix_acl().
242 * inode->i_mutex: down
243 * BKL held [before 2.5.x]
246 __reiserfs_set_acl(struct reiserfs_transaction_handle
*th
, struct inode
*inode
,
247 int type
, struct posix_acl
*acl
)
255 case ACL_TYPE_ACCESS
:
256 name
= XATTR_NAME_POSIX_ACL_ACCESS
;
258 case ACL_TYPE_DEFAULT
:
259 name
= XATTR_NAME_POSIX_ACL_DEFAULT
;
260 if (!S_ISDIR(inode
->i_mode
))
261 return acl
? -EACCES
: 0;
268 value
= reiserfs_posix_acl_to_disk(acl
, &size
);
270 return (int)PTR_ERR(value
);
273 error
= reiserfs_xattr_set_handle(th
, inode
, name
, value
, size
, 0);
276 * Ensure that the inode gets dirtied if we're only using
277 * the mode bits and an old ACL didn't exist. We don't need
278 * to check if the inode is hashed here since we won't get
279 * called by reiserfs_inherit_default_acl().
281 if (error
== -ENODATA
) {
283 if (type
== ACL_TYPE_ACCESS
) {
284 inode
->i_ctime
= current_time(inode
);
285 mark_inode_dirty(inode
);
292 set_cached_acl(inode
, type
, acl
);
298 * dir->i_mutex: locked,
299 * inode is new and not released into the wild yet
302 reiserfs_inherit_default_acl(struct reiserfs_transaction_handle
*th
,
303 struct inode
*dir
, struct dentry
*dentry
,
306 struct posix_acl
*default_acl
, *acl
;
309 /* ACLs only get applied to files and directories */
310 if (S_ISLNK(inode
->i_mode
))
314 * ACLs can only be used on "new" objects, so if it's an old object
315 * there is nothing to inherit from
317 if (get_inode_sd_version(dir
) == STAT_DATA_V1
)
321 * Don't apply ACLs to objects in the .reiserfs_priv tree.. This
322 * would be useless since permissions are ignored, and a pain because
323 * it introduces locking cycles
325 if (IS_PRIVATE(inode
))
328 err
= posix_acl_create(dir
, &inode
->i_mode
, &default_acl
, &acl
);
333 err
= __reiserfs_set_acl(th
, inode
, ACL_TYPE_DEFAULT
,
335 posix_acl_release(default_acl
);
339 err
= __reiserfs_set_acl(th
, inode
, ACL_TYPE_ACCESS
,
341 posix_acl_release(acl
);
347 /* no ACL, apply umask */
348 inode
->i_mode
&= ~current_umask();
352 /* This is used to cache the default acl before a new object is created.
353 * The biggest reason for this is to get an idea of how many blocks will
354 * actually be required for the create operation if we must inherit an ACL.
355 * An ACL write can add up to 3 object creations and an additional file write
356 * so we'd prefer not to reserve that many blocks in the journal if we can.
357 * It also has the advantage of not loading the ACL with a transaction open,
358 * this may seem silly, but if the owner of the directory is doing the
359 * creation, the ACL may not be loaded since the permissions wouldn't require
361 * We return the number of blocks required for the transaction.
363 int reiserfs_cache_default_acl(struct inode
*inode
)
365 struct posix_acl
*acl
;
368 if (IS_PRIVATE(inode
))
371 acl
= get_acl(inode
, ACL_TYPE_DEFAULT
);
373 if (acl
&& !IS_ERR(acl
)) {
374 int size
= reiserfs_acl_size(acl
->a_count
);
376 /* Other xattrs can be created during inode creation. We don't
377 * want to claim too many blocks, so we check to see if we
378 * need to create the tree to the xattrs, and then we
379 * just want two files. */
380 nblocks
= reiserfs_xattr_jcreate_nblocks(inode
);
381 nblocks
+= JOURNAL_BLOCKS_PER_OBJECT(inode
->i_sb
);
383 REISERFS_I(inode
)->i_flags
|= i_has_xattr_dir
;
385 /* We need to account for writes + bitmaps for two files */
386 nblocks
+= reiserfs_xattr_nblocks(inode
, size
) * 4;
387 posix_acl_release(acl
);
394 * Called under i_mutex
396 int reiserfs_acl_chmod(struct inode
*inode
)
398 if (IS_PRIVATE(inode
))
400 if (get_inode_sd_version(inode
) == STAT_DATA_V1
||
401 !reiserfs_posixacl(inode
->i_sb
))
404 return posix_acl_chmod(&init_user_ns
, inode
, inode
->i_mode
);