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6#include "xfs.h"
7#include "xfs_shared.h"
8#include "xfs_format.h"
9#include "xfs_log_format.h"
10#include "xfs_trans_resv.h"
11#include "xfs_mount.h"
12#include "xfs_inode.h"
13#include "xfs_attr.h"
14#include "xfs_trace.h"
15#include "xfs_error.h"
16#include "xfs_acl.h"
17#include "xfs_da_format.h"
18#include "xfs_da_btree.h"
19#include "xfs_trans.h"
20
21#include <linux/posix_acl_xattr.h>
22
23
24
25
26
27
28
29STATIC struct posix_acl *
30xfs_acl_from_disk(
31 struct xfs_mount *mp,
32 const struct xfs_acl *aclp,
33 int len,
34 int max_entries)
35{
36 struct posix_acl_entry *acl_e;
37 struct posix_acl *acl;
38 const struct xfs_acl_entry *ace;
39 unsigned int count, i;
40
41 if (len < sizeof(*aclp)) {
42 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, aclp,
43 len);
44 return ERR_PTR(-EFSCORRUPTED);
45 }
46
47 count = be32_to_cpu(aclp->acl_cnt);
48 if (count > max_entries || XFS_ACL_SIZE(count) != len) {
49 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, aclp,
50 len);
51 return ERR_PTR(-EFSCORRUPTED);
52 }
53
54 acl = posix_acl_alloc(count, GFP_KERNEL);
55 if (!acl)
56 return ERR_PTR(-ENOMEM);
57
58 for (i = 0; i < count; i++) {
59 acl_e = &acl->a_entries[i];
60 ace = &aclp->acl_entry[i];
61
62
63
64
65
66
67
68 acl_e->e_tag = be32_to_cpu(ace->ae_tag);
69 acl_e->e_perm = be16_to_cpu(ace->ae_perm);
70
71 switch (acl_e->e_tag) {
72 case ACL_USER:
73 acl_e->e_uid = make_kuid(&init_user_ns,
74 be32_to_cpu(ace->ae_id));
75 break;
76 case ACL_GROUP:
77 acl_e->e_gid = make_kgid(&init_user_ns,
78 be32_to_cpu(ace->ae_id));
79 break;
80 case ACL_USER_OBJ:
81 case ACL_GROUP_OBJ:
82 case ACL_MASK:
83 case ACL_OTHER:
84 break;
85 default:
86 goto fail;
87 }
88 }
89 return acl;
90
91fail:
92 posix_acl_release(acl);
93 return ERR_PTR(-EINVAL);
94}
95
96STATIC void
97xfs_acl_to_disk(struct xfs_acl *aclp, const struct posix_acl *acl)
98{
99 const struct posix_acl_entry *acl_e;
100 struct xfs_acl_entry *ace;
101 int i;
102
103 aclp->acl_cnt = cpu_to_be32(acl->a_count);
104 for (i = 0; i < acl->a_count; i++) {
105 ace = &aclp->acl_entry[i];
106 acl_e = &acl->a_entries[i];
107
108 ace->ae_tag = cpu_to_be32(acl_e->e_tag);
109 switch (acl_e->e_tag) {
110 case ACL_USER:
111 ace->ae_id = cpu_to_be32(
112 from_kuid(&init_user_ns, acl_e->e_uid));
113 break;
114 case ACL_GROUP:
115 ace->ae_id = cpu_to_be32(
116 from_kgid(&init_user_ns, acl_e->e_gid));
117 break;
118 default:
119 ace->ae_id = cpu_to_be32(ACL_UNDEFINED_ID);
120 break;
121 }
122
123 ace->ae_perm = cpu_to_be16(acl_e->e_perm);
124 }
125}
126
127struct posix_acl *
128xfs_get_acl(struct inode *inode, int type)
129{
130 struct xfs_inode *ip = XFS_I(inode);
131 struct xfs_mount *mp = ip->i_mount;
132 struct posix_acl *acl = NULL;
133 struct xfs_da_args args = {
134 .dp = ip,
135 .attr_filter = XFS_ATTR_ROOT,
136 .valuelen = XFS_ACL_MAX_SIZE(mp),
137 };
138 int error;
139
140 trace_xfs_get_acl(ip);
141
142 switch (type) {
143 case ACL_TYPE_ACCESS:
144 args.name = SGI_ACL_FILE;
145 break;
146 case ACL_TYPE_DEFAULT:
147 args.name = SGI_ACL_DEFAULT;
148 break;
149 default:
150 BUG();
151 }
152 args.namelen = strlen(args.name);
153
154
155
156
157
158 error = xfs_attr_get(&args);
159 if (!error) {
160 acl = xfs_acl_from_disk(mp, args.value, args.valuelen,
161 XFS_ACL_MAX_ENTRIES(mp));
162 } else if (error != -ENOATTR) {
163 acl = ERR_PTR(error);
164 }
165
166 kmem_free(args.value);
167 return acl;
168}
169
170int
171__xfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
172{
173 struct xfs_inode *ip = XFS_I(inode);
174 struct xfs_da_args args = {
175 .dp = ip,
176 .attr_filter = XFS_ATTR_ROOT,
177 };
178 int error;
179
180 switch (type) {
181 case ACL_TYPE_ACCESS:
182 args.name = SGI_ACL_FILE;
183 break;
184 case ACL_TYPE_DEFAULT:
185 if (!S_ISDIR(inode->i_mode))
186 return acl ? -EACCES : 0;
187 args.name = SGI_ACL_DEFAULT;
188 break;
189 default:
190 return -EINVAL;
191 }
192 args.namelen = strlen(args.name);
193
194 if (acl) {
195 args.valuelen = XFS_ACL_SIZE(acl->a_count);
196 args.value = kvzalloc(args.valuelen, GFP_KERNEL);
197 if (!args.value)
198 return -ENOMEM;
199 xfs_acl_to_disk(args.value, acl);
200 }
201
202 error = xfs_attr_set(&args);
203 kmem_free(args.value);
204
205
206
207
208 if (!acl && error == -ENOATTR)
209 error = 0;
210 if (!error)
211 set_cached_acl(inode, type, acl);
212 return error;
213}
214
215static int
216xfs_acl_set_mode(
217 struct inode *inode,
218 umode_t mode)
219{
220 struct xfs_inode *ip = XFS_I(inode);
221 struct xfs_mount *mp = ip->i_mount;
222 struct xfs_trans *tp;
223 int error;
224
225 error = xfs_trans_alloc(mp, &M_RES(mp)->tr_ichange, 0, 0, 0, &tp);
226 if (error)
227 return error;
228
229 xfs_ilock(ip, XFS_ILOCK_EXCL);
230 xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
231 inode->i_mode = mode;
232 inode->i_ctime = current_time(inode);
233 xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
234
235 if (mp->m_flags & XFS_MOUNT_WSYNC)
236 xfs_trans_set_sync(tp);
237 return xfs_trans_commit(tp);
238}
239
240int
241xfs_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
242 struct posix_acl *acl, int type)
243{
244 umode_t mode;
245 bool set_mode = false;
246 int error = 0;
247
248 if (!acl)
249 goto set_acl;
250
251 error = -E2BIG;
252 if (acl->a_count > XFS_ACL_MAX_ENTRIES(XFS_M(inode->i_sb)))
253 return error;
254
255 if (type == ACL_TYPE_ACCESS) {
256 error = posix_acl_update_mode(mnt_userns, inode, &mode, &acl);
257 if (error)
258 return error;
259 set_mode = true;
260 }
261
262 set_acl:
263
264
265
266
267
268 error = __xfs_set_acl(inode, acl, type);
269 if (!error && set_mode && mode != inode->i_mode)
270 error = xfs_acl_set_mode(inode, mode);
271 return error;
272}
273
274
275
276
277
278
279void
280xfs_forget_acl(
281 struct inode *inode,
282 const char *name)
283{
284 if (!strcmp(name, SGI_ACL_FILE))
285 forget_cached_acl(inode, ACL_TYPE_ACCESS);
286 else if (!strcmp(name, SGI_ACL_DEFAULT))
287 forget_cached_acl(inode, ACL_TYPE_DEFAULT);
288}
289