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 <linux/posix_acl_xattr.h>
20 * - all ACL updates are protected by inode->i_mutex, which is taken before
21 * calling into this file.
24 STATIC struct posix_acl *
26 const struct xfs_acl *aclp,
30 struct posix_acl_entry *acl_e;
31 struct posix_acl *acl;
32 const struct xfs_acl_entry *ace;
33 unsigned int count, i;
35 if (len < sizeof(*aclp))
36 return ERR_PTR(-EFSCORRUPTED);
37 count = be32_to_cpu(aclp->acl_cnt);
38 if (count > max_entries || XFS_ACL_SIZE(count) != len)
39 return ERR_PTR(-EFSCORRUPTED);
41 acl = posix_acl_alloc(count, GFP_KERNEL);
43 return ERR_PTR(-ENOMEM);
45 for (i = 0; i < count; i++) {
46 acl_e = &acl->a_entries[i];
47 ace = &aclp->acl_entry[i];
50 * The tag is 32 bits on disk and 16 bits in core.
52 * Because every access to it goes through the core
53 * format first this is not a problem.
55 acl_e->e_tag = be32_to_cpu(ace->ae_tag);
56 acl_e->e_perm = be16_to_cpu(ace->ae_perm);
58 switch (acl_e->e_tag) {
60 acl_e->e_uid = xfs_uid_to_kuid(be32_to_cpu(ace->ae_id));
63 acl_e->e_gid = xfs_gid_to_kgid(be32_to_cpu(ace->ae_id));
77 posix_acl_release(acl);
78 return ERR_PTR(-EINVAL);
82 xfs_acl_to_disk(struct xfs_acl *aclp, const struct posix_acl *acl)
84 const struct posix_acl_entry *acl_e;
85 struct xfs_acl_entry *ace;
88 aclp->acl_cnt = cpu_to_be32(acl->a_count);
89 for (i = 0; i < acl->a_count; i++) {
90 ace = &aclp->acl_entry[i];
91 acl_e = &acl->a_entries[i];
93 ace->ae_tag = cpu_to_be32(acl_e->e_tag);
94 switch (acl_e->e_tag) {
96 ace->ae_id = cpu_to_be32(xfs_kuid_to_uid(acl_e->e_uid));
99 ace->ae_id = cpu_to_be32(xfs_kgid_to_gid(acl_e->e_gid));
102 ace->ae_id = cpu_to_be32(ACL_UNDEFINED_ID);
106 ace->ae_perm = cpu_to_be16(acl_e->e_perm);
111 xfs_get_acl(struct inode *inode, int type)
113 struct xfs_inode *ip = XFS_I(inode);
114 struct posix_acl *acl = NULL;
115 struct xfs_acl *xfs_acl = NULL;
116 unsigned char *ea_name;
120 trace_xfs_get_acl(ip);
123 case ACL_TYPE_ACCESS:
124 ea_name = SGI_ACL_FILE;
126 case ACL_TYPE_DEFAULT:
127 ea_name = SGI_ACL_DEFAULT;
134 * If we have a cached ACLs value just return it, not need to
135 * go out to the disk.
137 len = XFS_ACL_MAX_SIZE(ip->i_mount);
138 error = xfs_attr_get(ip, ea_name, (unsigned char **)&xfs_acl, &len,
139 ATTR_ALLOC | ATTR_ROOT);
142 * If the attribute doesn't exist make sure we have a negative
143 * cache entry, for any other error assume it is transient.
145 if (error != -ENOATTR)
146 acl = ERR_PTR(error);
148 acl = xfs_acl_from_disk(xfs_acl, len,
149 XFS_ACL_MAX_ENTRIES(ip->i_mount));
156 __xfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
158 struct xfs_inode *ip = XFS_I(inode);
159 unsigned char *ea_name;
163 case ACL_TYPE_ACCESS:
164 ea_name = SGI_ACL_FILE;
166 case ACL_TYPE_DEFAULT:
167 if (!S_ISDIR(inode->i_mode))
168 return acl ? -EACCES : 0;
169 ea_name = SGI_ACL_DEFAULT;
176 struct xfs_acl *xfs_acl;
177 int len = XFS_ACL_MAX_SIZE(ip->i_mount);
179 xfs_acl = kmem_zalloc_large(len, 0);
183 xfs_acl_to_disk(xfs_acl, acl);
185 /* subtract away the unused acl entries */
186 len -= sizeof(struct xfs_acl_entry) *
187 (XFS_ACL_MAX_ENTRIES(ip->i_mount) - acl->a_count);
189 error = xfs_attr_set(ip, ea_name, (unsigned char *)xfs_acl,
195 * A NULL ACL argument means we want to remove the ACL.
197 error = xfs_attr_remove(ip, ea_name, ATTR_ROOT);
200 * If the attribute didn't exist to start with that's fine.
202 if (error == -ENOATTR)
207 set_cached_acl(inode, type, acl);
212 xfs_set_mode(struct inode *inode, umode_t mode)
216 if (mode != inode->i_mode) {
219 iattr.ia_valid = ATTR_MODE | ATTR_CTIME;
220 iattr.ia_mode = mode;
221 iattr.ia_ctime = current_time(inode);
223 error = xfs_setattr_nonsize(XFS_I(inode), &iattr, XFS_ATTR_NOACL);
230 xfs_set_acl(struct inode *inode, struct posix_acl *acl, int type)
233 bool set_mode = false;
240 if (acl->a_count > XFS_ACL_MAX_ENTRIES(XFS_M(inode->i_sb)))
243 if (type == ACL_TYPE_ACCESS) {
244 error = posix_acl_update_mode(inode, &mode, &acl);
251 error = __xfs_set_acl(inode, acl, type);
256 * We set the mode after successfully updating the ACL xattr because the
257 * xattr update can fail at ENOSPC and we don't want to change the mode
258 * if the ACL update hasn't been applied.
261 error = xfs_set_mode(inode, mode);