static int
xfs_xattr_acl_set(struct dentry *dentry, const char *name,
const void *value, size_t size, int flags, int type)
{
struct inode *inode = dentry->d_inode;
struct posix_acl *acl = NULL;
int error = 0;
if (flags & XATTR_CREATE)
return -EINVAL;
if (type == ACL_TYPE_DEFAULT && !S_ISDIR(inode->i_mode))
return value ? -EACCES : 0;
if ((current_fsuid() != inode->i_uid) && !capable(CAP_FOWNER))
return -EPERM;
if (!value)
goto set_acl;
acl = posix_acl_from_xattr(&init_user_ns, value, size);
if (!acl) {
/*
* acl_set_file(3) may request that we set default ACLs with
* zero length -- defend (gracefully) against that here.
*/
goto out;
}
if (IS_ERR(acl)) {
error = PTR_ERR(acl);
goto out;
}
error = posix_acl_valid(acl);
if (error)
goto out_release;
error = -EINVAL;
if (acl->a_count > XFS_ACL_MAX_ENTRIES(XFS_M(inode->i_sb)))
goto out_release;
if (type == ACL_TYPE_ACCESS) {
umode_t mode = inode->i_mode;
struct posix_acl *old_acl = acl;
error = posix_acl_update_mode(inode, &mode, &acl);
if (!acl)
posix_acl_release(old_acl);
if (error)
goto out_release;
error = xfs_set_mode(inode, mode);
if (error)
goto out_release;
}
set_acl:
error = xfs_set_acl(inode, type, acl);
out_release:
posix_acl_release(acl);
out:
return error;
}
STATIC int
xfs_set_acl(struct inode *inode, int type, struct posix_acl *acl)
{
struct xfs_inode *ip = XFS_I(inode);
unsigned char *ea_name;
int error;
if (S_ISLNK(inode->i_mode))
return -EOPNOTSUPP;
switch (type) {
case ACL_TYPE_ACCESS:
ea_name = SGI_ACL_FILE;
break;
case ACL_TYPE_DEFAULT:
if (!S_ISDIR(inode->i_mode))
return acl ? -EACCES : 0;
ea_name = SGI_ACL_DEFAULT;
break;
default:
return -EINVAL;
}
if (acl) {
struct xfs_acl *xfs_acl;
int len = XFS_ACL_MAX_SIZE(ip->i_mount);
xfs_acl = kzalloc(len, GFP_KERNEL);
if (!xfs_acl)
return -ENOMEM;
xfs_acl_to_disk(xfs_acl, acl);
/* subtract away the unused acl entries */
len -= sizeof(struct xfs_acl_entry) *
(XFS_ACL_MAX_ENTRIES(ip->i_mount) - acl->a_count);
error = -xfs_attr_set(ip, ea_name, (unsigned char *)xfs_acl,
len, ATTR_ROOT);
kfree(xfs_acl);
} else {
/*
* A NULL ACL argument means we want to remove the ACL.
*/
error = -xfs_attr_remove(ip, ea_name, ATTR_ROOT);
/*
* If the attribute didn't exist to start with that's fine.
*/
if (error == -ENOATTR)
error = 0;
}
if (!error)
set_cached_acl(inode, type, acl);
return error;
}
static int
xfs_acl_from_disk(
struct xfs_mount *mp,
struct xfs_icacl **aclp,
struct xfs_acl *dacl)
{
struct xfs_icacl *acl;
struct xfs_icacl_entry *ace;
struct xfs_acl_entry *dace;
int count;
int i;
count = be32_to_cpu(dacl->acl_cnt);
if (count > XFS_ACL_MAX_ENTRIES(mp)) {
do_warn(_("Too many ACL entries, count %d\n"), count);
*aclp = NULL;
return EINVAL;
}
acl = malloc(sizeof(struct xfs_icacl) +
count * sizeof(struct xfs_icacl_entry));
if (!acl) {
do_warn(_("cannot malloc enough for ACL attribute\n"));
do_warn(_("SKIPPING this ACL\n"));
*aclp = NULL;
return ENOMEM;
}
acl->acl_cnt = count;
for (i = 0; i < count; i++) {
ace = &acl->acl_entry[i];
dace = &dacl->acl_entry[i];
ace->ae_tag = be32_to_cpu(dace->ae_tag);
ace->ae_id = be32_to_cpu(dace->ae_id);
ace->ae_perm = be16_to_cpu(dace->ae_perm);
}
*aclp = acl;
return 0;
}
struct posix_acl *
xfs_get_acl(struct inode *inode, int type)
{
struct xfs_inode *ip = XFS_I(inode);
struct posix_acl *acl;
struct xfs_acl *xfs_acl;
unsigned char *ea_name;
int error;
int len;
acl = get_cached_acl(inode, type);
if (acl != ACL_NOT_CACHED)
return acl;
trace_xfs_get_acl(ip);
switch (type) {
case ACL_TYPE_ACCESS:
ea_name = SGI_ACL_FILE;
break;
case ACL_TYPE_DEFAULT:
ea_name = SGI_ACL_DEFAULT;
break;
default:
BUG();
}
/*
* If we have a cached ACLs value just return it, not need to
* go out to the disk.
*/
len = XFS_ACL_MAX_SIZE(ip->i_mount);
xfs_acl = kzalloc(len, GFP_KERNEL);
if (!xfs_acl)
return ERR_PTR(-ENOMEM);
error = -xfs_attr_get(ip, ea_name, (unsigned char *)xfs_acl,
&len, ATTR_ROOT);
if (error) {
/*
* If the attribute doesn't exist make sure we have a negative
* cache entry, for any other error assume it is transient and
* leave the cache entry as ACL_NOT_CACHED.
*/
if (error == -ENOATTR) {
acl = NULL;
goto out_update_cache;
}
goto out;
}
acl = xfs_acl_from_disk(xfs_acl, XFS_ACL_MAX_ENTRIES(ip->i_mount));
if (IS_ERR(acl))
goto out;
out_update_cache:
set_cached_acl(inode, type, acl);
out:
kfree(xfs_acl);
return acl;
}
