Commit | Line | Data |
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652ecc20 KK |
1 | /* |
2 | * JFFS2 -- Journalling Flash File System, Version 2. | |
aa98d7cf | 3 | * |
c00c310e | 4 | * Copyright © 2006 NEC Corporation |
aa98d7cf | 5 | * |
652ecc20 KK |
6 | * Created by KaiGai Kohei <kaigai@ak.jp.nec.com> |
7 | * | |
8 | * For licensing information, see the file 'LICENCE' in this directory. | |
9 | * | |
10 | */ | |
c00c310e | 11 | |
5a528957 JP |
12 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
13 | ||
aa98d7cf KK |
14 | #include <linux/kernel.h> |
15 | #include <linux/slab.h> | |
16 | #include <linux/fs.h> | |
914e2637 | 17 | #include <linux/sched.h> |
aa98d7cf KK |
18 | #include <linux/time.h> |
19 | #include <linux/crc32.h> | |
20 | #include <linux/jffs2.h> | |
21 | #include <linux/xattr.h> | |
22 | #include <linux/posix_acl_xattr.h> | |
23 | #include <linux/mtd/mtd.h> | |
24 | #include "nodelist.h" | |
25 | ||
26 | static size_t jffs2_acl_size(int count) | |
27 | { | |
28 | if (count <= 4) { | |
de1f72fa KK |
29 | return sizeof(struct jffs2_acl_header) |
30 | + count * sizeof(struct jffs2_acl_entry_short); | |
aa98d7cf | 31 | } else { |
de1f72fa KK |
32 | return sizeof(struct jffs2_acl_header) |
33 | + 4 * sizeof(struct jffs2_acl_entry_short) | |
34 | + (count - 4) * sizeof(struct jffs2_acl_entry); | |
aa98d7cf KK |
35 | } |
36 | } | |
37 | ||
38 | static int jffs2_acl_count(size_t size) | |
39 | { | |
40 | size_t s; | |
41 | ||
de1f72fa | 42 | size -= sizeof(struct jffs2_acl_header); |
fc371a25 | 43 | if (size < 4 * sizeof(struct jffs2_acl_entry_short)) { |
de1f72fa | 44 | if (size % sizeof(struct jffs2_acl_entry_short)) |
aa98d7cf | 45 | return -1; |
de1f72fa | 46 | return size / sizeof(struct jffs2_acl_entry_short); |
aa98d7cf | 47 | } else { |
fc371a25 | 48 | s = size - 4 * sizeof(struct jffs2_acl_entry_short); |
de1f72fa | 49 | if (s % sizeof(struct jffs2_acl_entry)) |
aa98d7cf | 50 | return -1; |
de1f72fa | 51 | return s / sizeof(struct jffs2_acl_entry) + 4; |
aa98d7cf KK |
52 | } |
53 | } | |
54 | ||
dea80134 | 55 | static struct posix_acl *jffs2_acl_from_medium(void *value, size_t size) |
aa98d7cf | 56 | { |
dea80134 KK |
57 | void *end = value + size; |
58 | struct jffs2_acl_header *header = value; | |
59 | struct jffs2_acl_entry *entry; | |
aa98d7cf KK |
60 | struct posix_acl *acl; |
61 | uint32_t ver; | |
62 | int i, count; | |
63 | ||
64 | if (!value) | |
65 | return NULL; | |
de1f72fa | 66 | if (size < sizeof(struct jffs2_acl_header)) |
aa98d7cf | 67 | return ERR_PTR(-EINVAL); |
dea80134 | 68 | ver = je32_to_cpu(header->a_version); |
aa98d7cf KK |
69 | if (ver != JFFS2_ACL_VERSION) { |
70 | JFFS2_WARNING("Invalid ACL version. (=%u)\n", ver); | |
71 | return ERR_PTR(-EINVAL); | |
72 | } | |
73 | ||
dea80134 | 74 | value += sizeof(struct jffs2_acl_header); |
aa98d7cf KK |
75 | count = jffs2_acl_count(size); |
76 | if (count < 0) | |
77 | return ERR_PTR(-EINVAL); | |
78 | if (count == 0) | |
79 | return NULL; | |
80 | ||
81 | acl = posix_acl_alloc(count, GFP_KERNEL); | |
82 | if (!acl) | |
83 | return ERR_PTR(-ENOMEM); | |
84 | ||
85 | for (i=0; i < count; i++) { | |
dea80134 KK |
86 | entry = value; |
87 | if (value + sizeof(struct jffs2_acl_entry_short) > end) | |
aa98d7cf KK |
88 | goto fail; |
89 | acl->a_entries[i].e_tag = je16_to_cpu(entry->e_tag); | |
90 | acl->a_entries[i].e_perm = je16_to_cpu(entry->e_perm); | |
91 | switch (acl->a_entries[i].e_tag) { | |
92 | case ACL_USER_OBJ: | |
93 | case ACL_GROUP_OBJ: | |
94 | case ACL_MASK: | |
95 | case ACL_OTHER: | |
dea80134 | 96 | value += sizeof(struct jffs2_acl_entry_short); |
aa98d7cf KK |
97 | break; |
98 | ||
99 | case ACL_USER: | |
0cfe53d3 EB |
100 | value += sizeof(struct jffs2_acl_entry); |
101 | if (value > end) | |
102 | goto fail; | |
103 | acl->a_entries[i].e_uid = | |
104 | make_kuid(&init_user_ns, | |
105 | je32_to_cpu(entry->e_id)); | |
106 | break; | |
aa98d7cf | 107 | case ACL_GROUP: |
dea80134 KK |
108 | value += sizeof(struct jffs2_acl_entry); |
109 | if (value > end) | |
aa98d7cf | 110 | goto fail; |
0cfe53d3 EB |
111 | acl->a_entries[i].e_gid = |
112 | make_kgid(&init_user_ns, | |
113 | je32_to_cpu(entry->e_id)); | |
aa98d7cf KK |
114 | break; |
115 | ||
116 | default: | |
117 | goto fail; | |
118 | } | |
119 | } | |
120 | if (value != end) | |
121 | goto fail; | |
122 | return acl; | |
123 | fail: | |
124 | posix_acl_release(acl); | |
125 | return ERR_PTR(-EINVAL); | |
126 | } | |
127 | ||
128 | static void *jffs2_acl_to_medium(const struct posix_acl *acl, size_t *size) | |
129 | { | |
dea80134 KK |
130 | struct jffs2_acl_header *header; |
131 | struct jffs2_acl_entry *entry; | |
132 | void *e; | |
aa98d7cf KK |
133 | size_t i; |
134 | ||
135 | *size = jffs2_acl_size(acl->a_count); | |
a3ac9730 MW |
136 | header = kmalloc(struct_size(header, a_entries, acl->a_count), |
137 | GFP_KERNEL); | |
dea80134 | 138 | if (!header) |
aa98d7cf | 139 | return ERR_PTR(-ENOMEM); |
dea80134 KK |
140 | header->a_version = cpu_to_je32(JFFS2_ACL_VERSION); |
141 | e = header + 1; | |
aa98d7cf | 142 | for (i=0; i < acl->a_count; i++) { |
0cfe53d3 | 143 | const struct posix_acl_entry *acl_e = &acl->a_entries[i]; |
dea80134 | 144 | entry = e; |
0cfe53d3 EB |
145 | entry->e_tag = cpu_to_je16(acl_e->e_tag); |
146 | entry->e_perm = cpu_to_je16(acl_e->e_perm); | |
147 | switch(acl_e->e_tag) { | |
aa98d7cf | 148 | case ACL_USER: |
0cfe53d3 EB |
149 | entry->e_id = cpu_to_je32( |
150 | from_kuid(&init_user_ns, acl_e->e_uid)); | |
151 | e += sizeof(struct jffs2_acl_entry); | |
152 | break; | |
aa98d7cf | 153 | case ACL_GROUP: |
0cfe53d3 EB |
154 | entry->e_id = cpu_to_je32( |
155 | from_kgid(&init_user_ns, acl_e->e_gid)); | |
de1f72fa | 156 | e += sizeof(struct jffs2_acl_entry); |
aa98d7cf KK |
157 | break; |
158 | ||
159 | case ACL_USER_OBJ: | |
160 | case ACL_GROUP_OBJ: | |
161 | case ACL_MASK: | |
162 | case ACL_OTHER: | |
de1f72fa | 163 | e += sizeof(struct jffs2_acl_entry_short); |
aa98d7cf KK |
164 | break; |
165 | ||
166 | default: | |
167 | goto fail; | |
168 | } | |
169 | } | |
dea80134 | 170 | return header; |
aa98d7cf | 171 | fail: |
dea80134 | 172 | kfree(header); |
aa98d7cf KK |
173 | return ERR_PTR(-EINVAL); |
174 | } | |
175 | ||
0cad6246 | 176 | struct posix_acl *jffs2_get_acl(struct inode *inode, int type, bool rcu) |
aa98d7cf | 177 | { |
aa98d7cf KK |
178 | struct posix_acl *acl; |
179 | char *value = NULL; | |
180 | int rc, xprefix; | |
181 | ||
0cad6246 MS |
182 | if (rcu) |
183 | return ERR_PTR(-ECHILD); | |
184 | ||
aa98d7cf KK |
185 | switch (type) { |
186 | case ACL_TYPE_ACCESS: | |
aa98d7cf KK |
187 | xprefix = JFFS2_XPREFIX_ACL_ACCESS; |
188 | break; | |
189 | case ACL_TYPE_DEFAULT: | |
aa98d7cf KK |
190 | xprefix = JFFS2_XPREFIX_ACL_DEFAULT; |
191 | break; | |
192 | default: | |
073aaa1b | 193 | BUG(); |
aa98d7cf KK |
194 | } |
195 | rc = do_jffs2_getxattr(inode, xprefix, "", NULL, 0); | |
196 | if (rc > 0) { | |
197 | value = kmalloc(rc, GFP_KERNEL); | |
198 | if (!value) | |
199 | return ERR_PTR(-ENOMEM); | |
200 | rc = do_jffs2_getxattr(inode, xprefix, "", value, rc); | |
201 | } | |
202 | if (rc > 0) { | |
203 | acl = jffs2_acl_from_medium(value, rc); | |
204 | } else if (rc == -ENODATA || rc == -ENOSYS) { | |
205 | acl = NULL; | |
206 | } else { | |
207 | acl = ERR_PTR(rc); | |
208 | } | |
b6861d0a | 209 | kfree(value); |
aa98d7cf KK |
210 | return acl; |
211 | } | |
212 | ||
cfc8dc6f KK |
213 | static int __jffs2_set_acl(struct inode *inode, int xprefix, struct posix_acl *acl) |
214 | { | |
215 | char *value = NULL; | |
216 | size_t size = 0; | |
217 | int rc; | |
218 | ||
219 | if (acl) { | |
220 | value = jffs2_acl_to_medium(acl, &size); | |
221 | if (IS_ERR(value)) | |
222 | return PTR_ERR(value); | |
223 | } | |
224 | rc = do_jffs2_setxattr(inode, xprefix, "", value, size, 0); | |
225 | if (!value && rc == -ENODATA) | |
226 | rc = 0; | |
227 | kfree(value); | |
228 | ||
229 | return rc; | |
230 | } | |
231 | ||
13e83a49 | 232 | int jffs2_set_acl(struct mnt_idmap *idmap, struct dentry *dentry, |
549c7297 | 233 | struct posix_acl *acl, int type) |
aa98d7cf | 234 | { |
aa98d7cf | 235 | int rc, xprefix; |
138060ba | 236 | struct inode *inode = d_inode(dentry); |
aa98d7cf | 237 | |
aa98d7cf KK |
238 | switch (type) { |
239 | case ACL_TYPE_ACCESS: | |
240 | xprefix = JFFS2_XPREFIX_ACL_ACCESS; | |
241 | if (acl) { | |
07393101 JK |
242 | umode_t mode; |
243 | ||
700b7940 | 244 | rc = posix_acl_update_mode(&nop_mnt_idmap, inode, &mode, |
e65ce2a5 | 245 | &acl); |
07393101 | 246 | if (rc) |
aa98d7cf KK |
247 | return rc; |
248 | if (inode->i_mode != mode) { | |
9ed437c5 DW |
249 | struct iattr attr; |
250 | ||
1c24d06f | 251 | attr.ia_valid = ATTR_MODE | ATTR_CTIME; |
9ed437c5 | 252 | attr.ia_mode = mode; |
02027d42 | 253 | attr.ia_ctime = current_time(inode); |
9ed437c5 DW |
254 | rc = jffs2_do_setattr(inode, &attr); |
255 | if (rc < 0) | |
256 | return rc; | |
aa98d7cf | 257 | } |
aa98d7cf KK |
258 | } |
259 | break; | |
260 | case ACL_TYPE_DEFAULT: | |
261 | xprefix = JFFS2_XPREFIX_ACL_DEFAULT; | |
262 | if (!S_ISDIR(inode->i_mode)) | |
263 | return acl ? -EACCES : 0; | |
264 | break; | |
265 | default: | |
266 | return -EINVAL; | |
267 | } | |
cfc8dc6f | 268 | rc = __jffs2_set_acl(inode, xprefix, acl); |
073aaa1b AV |
269 | if (!rc) |
270 | set_cached_acl(inode, type, acl); | |
aa98d7cf KK |
271 | return rc; |
272 | } | |
273 | ||
d3fb6120 | 274 | int jffs2_init_acl_pre(struct inode *dir_i, struct inode *inode, umode_t *i_mode) |
aa98d7cf | 275 | { |
f2963d45 | 276 | struct posix_acl *default_acl, *acl; |
cfc8dc6f | 277 | int rc; |
aa98d7cf | 278 | |
72c04902 | 279 | cache_no_acl(inode); |
cfc8dc6f | 280 | |
f2963d45 CH |
281 | rc = posix_acl_create(dir_i, i_mode, &default_acl, &acl); |
282 | if (rc) | |
283 | return rc; | |
cfc8dc6f | 284 | |
f2963d45 CH |
285 | if (default_acl) { |
286 | set_cached_acl(inode, ACL_TYPE_DEFAULT, default_acl); | |
287 | posix_acl_release(default_acl); | |
288 | } | |
289 | if (acl) { | |
290 | set_cached_acl(inode, ACL_TYPE_ACCESS, acl); | |
826cae2f | 291 | posix_acl_release(acl); |
aa98d7cf | 292 | } |
cfc8dc6f KK |
293 | return 0; |
294 | } | |
295 | ||
296 | int jffs2_init_acl_post(struct inode *inode) | |
297 | { | |
cfc8dc6f KK |
298 | int rc; |
299 | ||
290c263b AV |
300 | if (inode->i_default_acl) { |
301 | rc = __jffs2_set_acl(inode, JFFS2_XPREFIX_ACL_DEFAULT, inode->i_default_acl); | |
cfc8dc6f KK |
302 | if (rc) |
303 | return rc; | |
304 | } | |
305 | ||
290c263b AV |
306 | if (inode->i_acl) { |
307 | rc = __jffs2_set_acl(inode, JFFS2_XPREFIX_ACL_ACCESS, inode->i_acl); | |
cfc8dc6f KK |
308 | if (rc) |
309 | return rc; | |
310 | } | |
311 | ||
8d6ea587 | 312 | return 0; |
aa98d7cf | 313 | } |