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"
18 #include <linux/posix_acl_xattr.h>
22 * - all ACL updates are protected by inode->i_mutex, which is taken before
23 * calling into this file.
26 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 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, aclp,
41 return ERR_PTR(-EFSCORRUPTED);
44 count = be32_to_cpu(aclp->acl_cnt);
45 if (count > max_entries || XFS_ACL_SIZE(count) != len) {
46 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, aclp,
48 return ERR_PTR(-EFSCORRUPTED);
51 acl = posix_acl_alloc(count, GFP_KERNEL);
53 return ERR_PTR(-ENOMEM);
55 for (i = 0; i < count; i++) {
56 acl_e = &acl->a_entries[i];
57 ace = &aclp->acl_entry[i];
60 * The tag is 32 bits on disk and 16 bits in core.
62 * Because every access to it goes through the core
63 * format first this is not a problem.
65 acl_e->e_tag = be32_to_cpu(ace->ae_tag);
66 acl_e->e_perm = be16_to_cpu(ace->ae_perm);
68 switch (acl_e->e_tag) {
70 acl_e->e_uid = xfs_uid_to_kuid(be32_to_cpu(ace->ae_id));
73 acl_e->e_gid = xfs_gid_to_kgid(be32_to_cpu(ace->ae_id));
87 posix_acl_release(acl);
88 return ERR_PTR(-EINVAL);
92 xfs_acl_to_disk(struct xfs_acl *aclp, const struct posix_acl *acl)
94 const struct posix_acl_entry *acl_e;
95 struct xfs_acl_entry *ace;
98 aclp->acl_cnt = cpu_to_be32(acl->a_count);
99 for (i = 0; i < acl->a_count; i++) {
100 ace = &aclp->acl_entry[i];
101 acl_e = &acl->a_entries[i];
103 ace->ae_tag = cpu_to_be32(acl_e->e_tag);
104 switch (acl_e->e_tag) {
106 ace->ae_id = cpu_to_be32(xfs_kuid_to_uid(acl_e->e_uid));
109 ace->ae_id = cpu_to_be32(xfs_kgid_to_gid(acl_e->e_gid));
112 ace->ae_id = cpu_to_be32(ACL_UNDEFINED_ID);
116 ace->ae_perm = cpu_to_be16(acl_e->e_perm);
121 xfs_get_acl(struct inode *inode, int type)
123 struct xfs_inode *ip = XFS_I(inode);
124 struct posix_acl *acl = NULL;
125 struct xfs_acl *xfs_acl = NULL;
126 unsigned char *ea_name;
130 trace_xfs_get_acl(ip);
133 case ACL_TYPE_ACCESS:
134 ea_name = SGI_ACL_FILE;
136 case ACL_TYPE_DEFAULT:
137 ea_name = SGI_ACL_DEFAULT;
144 * If we have a cached ACLs value just return it, not need to
145 * go out to the disk.
147 len = XFS_ACL_MAX_SIZE(ip->i_mount);
148 error = xfs_attr_get(ip, ea_name, (unsigned char **)&xfs_acl, &len,
149 ATTR_ALLOC | ATTR_ROOT);
152 * If the attribute doesn't exist make sure we have a negative
153 * cache entry, for any other error assume it is transient.
155 if (error != -ENOATTR)
156 acl = ERR_PTR(error);
158 acl = xfs_acl_from_disk(ip->i_mount, xfs_acl, len,
159 XFS_ACL_MAX_ENTRIES(ip->i_mount));
166 __xfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
168 struct xfs_inode *ip = XFS_I(inode);
169 unsigned char *ea_name;
173 case ACL_TYPE_ACCESS:
174 ea_name = SGI_ACL_FILE;
176 case ACL_TYPE_DEFAULT:
177 if (!S_ISDIR(inode->i_mode))
178 return acl ? -EACCES : 0;
179 ea_name = SGI_ACL_DEFAULT;
186 struct xfs_acl *xfs_acl;
187 int len = XFS_ACL_MAX_SIZE(ip->i_mount);
189 xfs_acl = kmem_zalloc_large(len, 0);
193 xfs_acl_to_disk(xfs_acl, acl);
195 /* subtract away the unused acl entries */
196 len -= sizeof(struct xfs_acl_entry) *
197 (XFS_ACL_MAX_ENTRIES(ip->i_mount) - acl->a_count);
199 error = xfs_attr_set(ip, ea_name, (unsigned char *)xfs_acl,
205 * A NULL ACL argument means we want to remove the ACL.
207 error = xfs_attr_remove(ip, ea_name, ATTR_ROOT);
210 * If the attribute didn't exist to start with that's fine.
212 if (error == -ENOATTR)
217 set_cached_acl(inode, type, acl);
222 xfs_set_mode(struct inode *inode, umode_t mode)
226 if (mode != inode->i_mode) {
229 iattr.ia_valid = ATTR_MODE | ATTR_CTIME;
230 iattr.ia_mode = mode;
231 iattr.ia_ctime = current_time(inode);
233 error = xfs_setattr_nonsize(XFS_I(inode), &iattr, XFS_ATTR_NOACL);
240 xfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
243 bool set_mode = false;
250 if (acl->a_count > XFS_ACL_MAX_ENTRIES(XFS_M(inode->i_sb)))
253 if (type == ACL_TYPE_ACCESS) {
254 error = posix_acl_update_mode(inode, &mode, &acl);
261 error = __xfs_set_acl(inode, acl, type);
266 * We set the mode after successfully updating the ACL xattr because the
267 * xattr update can fail at ENOSPC and we don't want to change the mode
268 * if the ACL update hasn't been applied.
271 error = xfs_set_mode(inode, mode);