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"
14 #include "xfs_trace.h"
15 #include "xfs_error.h"
16 #include <linux/posix_acl_xattr.h>
21 * - all ACL updates are protected by inode->i_mutex, which is taken before
22 * calling into this file.
25 STATIC struct posix_acl *
28 const struct xfs_acl *aclp,
32 struct posix_acl_entry *acl_e;
33 struct posix_acl *acl;
34 const struct xfs_acl_entry *ace;
35 unsigned int count, i;
37 if (len < sizeof(*aclp)) {
38 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, aclp,
40 return ERR_PTR(-EFSCORRUPTED);
43 count = be32_to_cpu(aclp->acl_cnt);
44 if (count > max_entries || XFS_ACL_SIZE(count) != len) {
45 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, aclp,
47 return ERR_PTR(-EFSCORRUPTED);
50 acl = posix_acl_alloc(count, GFP_KERNEL);
52 return ERR_PTR(-ENOMEM);
54 for (i = 0; i < count; i++) {
55 acl_e = &acl->a_entries[i];
56 ace = &aclp->acl_entry[i];
59 * The tag is 32 bits on disk and 16 bits in core.
61 * Because every access to it goes through the core
62 * format first this is not a problem.
64 acl_e->e_tag = be32_to_cpu(ace->ae_tag);
65 acl_e->e_perm = be16_to_cpu(ace->ae_perm);
67 switch (acl_e->e_tag) {
69 acl_e->e_uid = make_kuid(&init_user_ns,
70 be32_to_cpu(ace->ae_id));
73 acl_e->e_gid = make_kgid(&init_user_ns,
74 be32_to_cpu(ace->ae_id));
88 posix_acl_release(acl);
89 return ERR_PTR(-EINVAL);
93 xfs_acl_to_disk(struct xfs_acl *aclp, const struct posix_acl *acl)
95 const struct posix_acl_entry *acl_e;
96 struct xfs_acl_entry *ace;
99 aclp->acl_cnt = cpu_to_be32(acl->a_count);
100 for (i = 0; i < acl->a_count; i++) {
101 ace = &aclp->acl_entry[i];
102 acl_e = &acl->a_entries[i];
104 ace->ae_tag = cpu_to_be32(acl_e->e_tag);
105 switch (acl_e->e_tag) {
107 ace->ae_id = cpu_to_be32(
108 from_kuid(&init_user_ns, acl_e->e_uid));
111 ace->ae_id = cpu_to_be32(
112 from_kgid(&init_user_ns, acl_e->e_gid));
115 ace->ae_id = cpu_to_be32(ACL_UNDEFINED_ID);
119 ace->ae_perm = cpu_to_be16(acl_e->e_perm);
124 xfs_get_acl(struct inode *inode, int type)
126 struct xfs_inode *ip = XFS_I(inode);
127 struct posix_acl *acl = NULL;
128 struct xfs_acl *xfs_acl = NULL;
129 unsigned char *ea_name;
133 trace_xfs_get_acl(ip);
136 case ACL_TYPE_ACCESS:
137 ea_name = SGI_ACL_FILE;
139 case ACL_TYPE_DEFAULT:
140 ea_name = SGI_ACL_DEFAULT;
147 * If we have a cached ACLs value just return it, not need to
148 * go out to the disk.
150 len = XFS_ACL_MAX_SIZE(ip->i_mount);
151 error = xfs_attr_get(ip, ea_name, (unsigned char **)&xfs_acl, &len,
152 ATTR_ALLOC | ATTR_ROOT);
155 * If the attribute doesn't exist make sure we have a negative
156 * cache entry, for any other error assume it is transient.
158 if (error != -ENOATTR)
159 acl = ERR_PTR(error);
161 acl = xfs_acl_from_disk(ip->i_mount, xfs_acl, len,
162 XFS_ACL_MAX_ENTRIES(ip->i_mount));
169 __xfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
171 struct xfs_inode *ip = XFS_I(inode);
172 unsigned char *ea_name;
176 case ACL_TYPE_ACCESS:
177 ea_name = SGI_ACL_FILE;
179 case ACL_TYPE_DEFAULT:
180 if (!S_ISDIR(inode->i_mode))
181 return acl ? -EACCES : 0;
182 ea_name = SGI_ACL_DEFAULT;
189 struct xfs_acl *xfs_acl;
190 int len = XFS_ACL_MAX_SIZE(ip->i_mount);
192 xfs_acl = kmem_zalloc_large(len, 0);
196 xfs_acl_to_disk(xfs_acl, acl);
198 /* subtract away the unused acl entries */
199 len -= sizeof(struct xfs_acl_entry) *
200 (XFS_ACL_MAX_ENTRIES(ip->i_mount) - acl->a_count);
202 error = xfs_attr_set(ip, ea_name, (unsigned char *)xfs_acl,
208 * A NULL ACL argument means we want to remove the ACL.
210 error = xfs_attr_remove(ip, ea_name, ATTR_ROOT);
213 * If the attribute didn't exist to start with that's fine.
215 if (error == -ENOATTR)
220 set_cached_acl(inode, type, acl);
225 xfs_set_mode(struct inode *inode, umode_t mode)
229 if (mode != inode->i_mode) {
232 iattr.ia_valid = ATTR_MODE | ATTR_CTIME;
233 iattr.ia_mode = mode;
234 iattr.ia_ctime = current_time(inode);
236 error = xfs_setattr_nonsize(XFS_I(inode), &iattr, XFS_ATTR_NOACL);
243 xfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
246 bool set_mode = false;
253 if (acl->a_count > XFS_ACL_MAX_ENTRIES(XFS_M(inode->i_sb)))
256 if (type == ACL_TYPE_ACCESS) {
257 error = posix_acl_update_mode(inode, &mode, &acl);
264 error = __xfs_set_acl(inode, acl, type);
269 * We set the mode after successfully updating the ACL xattr because the
270 * xattr update can fail at ENOSPC and we don't want to change the mode
271 * if the ACL update hasn't been applied.
274 error = xfs_set_mode(inode, mode);