1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright (c) 2008, Christoph Hellwig
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"
15 #include "xfs_trace.h"
16 #include <linux/slab.h>
17 #include <linux/xattr.h>
18 #include <linux/posix_acl_xattr.h>
23 * - all ACL updates are protected by inode->i_mutex, which is taken before
24 * calling into this file.
27 STATIC struct posix_acl *
29 const struct xfs_acl *aclp,
33 struct posix_acl_entry *acl_e;
34 struct posix_acl *acl;
35 const struct xfs_acl_entry *ace;
36 unsigned int count, i;
38 if (len < sizeof(*aclp))
39 return ERR_PTR(-EFSCORRUPTED);
40 count = be32_to_cpu(aclp->acl_cnt);
41 if (count > max_entries || XFS_ACL_SIZE(count) != len)
42 return ERR_PTR(-EFSCORRUPTED);
44 acl = posix_acl_alloc(count, GFP_KERNEL);
46 return ERR_PTR(-ENOMEM);
48 for (i = 0; i < count; i++) {
49 acl_e = &acl->a_entries[i];
50 ace = &aclp->acl_entry[i];
53 * The tag is 32 bits on disk and 16 bits in core.
55 * Because every access to it goes through the core
56 * format first this is not a problem.
58 acl_e->e_tag = be32_to_cpu(ace->ae_tag);
59 acl_e->e_perm = be16_to_cpu(ace->ae_perm);
61 switch (acl_e->e_tag) {
63 acl_e->e_uid = xfs_uid_to_kuid(be32_to_cpu(ace->ae_id));
66 acl_e->e_gid = xfs_gid_to_kgid(be32_to_cpu(ace->ae_id));
80 posix_acl_release(acl);
81 return ERR_PTR(-EINVAL);
85 xfs_acl_to_disk(struct xfs_acl *aclp, const struct posix_acl *acl)
87 const struct posix_acl_entry *acl_e;
88 struct xfs_acl_entry *ace;
91 aclp->acl_cnt = cpu_to_be32(acl->a_count);
92 for (i = 0; i < acl->a_count; i++) {
93 ace = &aclp->acl_entry[i];
94 acl_e = &acl->a_entries[i];
96 ace->ae_tag = cpu_to_be32(acl_e->e_tag);
97 switch (acl_e->e_tag) {
99 ace->ae_id = cpu_to_be32(xfs_kuid_to_uid(acl_e->e_uid));
102 ace->ae_id = cpu_to_be32(xfs_kgid_to_gid(acl_e->e_gid));
105 ace->ae_id = cpu_to_be32(ACL_UNDEFINED_ID);
109 ace->ae_perm = cpu_to_be16(acl_e->e_perm);
114 xfs_get_acl(struct inode *inode, int type)
116 struct xfs_inode *ip = XFS_I(inode);
117 struct posix_acl *acl = NULL;
118 struct xfs_acl *xfs_acl;
119 unsigned char *ea_name;
123 trace_xfs_get_acl(ip);
126 case ACL_TYPE_ACCESS:
127 ea_name = SGI_ACL_FILE;
129 case ACL_TYPE_DEFAULT:
130 ea_name = SGI_ACL_DEFAULT;
137 * If we have a cached ACLs value just return it, not need to
138 * go out to the disk.
140 len = XFS_ACL_MAX_SIZE(ip->i_mount);
141 xfs_acl = kmem_zalloc_large(len, KM_SLEEP);
143 return ERR_PTR(-ENOMEM);
145 error = xfs_attr_get(ip, ea_name, (unsigned char *)xfs_acl,
149 * If the attribute doesn't exist make sure we have a negative
150 * cache entry, for any other error assume it is transient.
152 if (error != -ENOATTR)
153 acl = ERR_PTR(error);
155 acl = xfs_acl_from_disk(xfs_acl, len,
156 XFS_ACL_MAX_ENTRIES(ip->i_mount));
163 __xfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
165 struct xfs_inode *ip = XFS_I(inode);
166 unsigned char *ea_name;
170 case ACL_TYPE_ACCESS:
171 ea_name = SGI_ACL_FILE;
173 case ACL_TYPE_DEFAULT:
174 if (!S_ISDIR(inode->i_mode))
175 return acl ? -EACCES : 0;
176 ea_name = SGI_ACL_DEFAULT;
183 struct xfs_acl *xfs_acl;
184 int len = XFS_ACL_MAX_SIZE(ip->i_mount);
186 xfs_acl = kmem_zalloc_large(len, KM_SLEEP);
190 xfs_acl_to_disk(xfs_acl, acl);
192 /* subtract away the unused acl entries */
193 len -= sizeof(struct xfs_acl_entry) *
194 (XFS_ACL_MAX_ENTRIES(ip->i_mount) - acl->a_count);
196 error = xfs_attr_set(ip, ea_name, (unsigned char *)xfs_acl,
202 * A NULL ACL argument means we want to remove the ACL.
204 error = xfs_attr_remove(ip, ea_name, ATTR_ROOT);
207 * If the attribute didn't exist to start with that's fine.
209 if (error == -ENOATTR)
214 set_cached_acl(inode, type, acl);
219 xfs_set_mode(struct inode *inode, umode_t mode)
223 if (mode != inode->i_mode) {
226 iattr.ia_valid = ATTR_MODE | ATTR_CTIME;
227 iattr.ia_mode = mode;
228 iattr.ia_ctime = current_time(inode);
230 error = xfs_setattr_nonsize(XFS_I(inode), &iattr, XFS_ATTR_NOACL);
237 xfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
240 bool set_mode = false;
247 if (acl->a_count > XFS_ACL_MAX_ENTRIES(XFS_M(inode->i_sb)))
250 if (type == ACL_TYPE_ACCESS) {
251 error = posix_acl_update_mode(inode, &mode, &acl);
258 error = __xfs_set_acl(inode, acl, type);
263 * We set the mode after successfully updating the ACL xattr because the
264 * xattr update can fail at ENOSPC and we don't want to change the mode
265 * if the ACL update hasn't been applied.
268 error = xfs_set_mode(inode, mode);