ceph: allow arbitrary security.* xattrs

Most filesystems don't limit what security.* xattrs can be set or
fetched. I see no reason that we need to limit that on cephfs either.

Drop the special xattr handler for "security." xattrs, and allow the
"other" xattr handler to handle security xattrs as well.

In addition to fixing xfstest generic/093, this allows us to support
per-file capabilities (a'la setcap(8)).

Link: https://tracker.ceph.com/issues/41135
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

diff --git a/fs/ceph/xattr.c b/fs/ceph/xattr.c
index 410eaf1ba2112e6f3fc75dfbaeab32573fdb9e61..cb18ee637cb7b66ee37221ceb9e521c852eec4b1 100644 (file)
--- a/fs/ceph/xattr.c
+++ b/fs/ceph/xattr.c
@@ -20,7 +20,8 @@ static int __remove_xattr(struct ceph_inode_info *ci,
 
 static bool ceph_is_valid_xattr(const char *name)
 {
-       return !strncmp(name, XATTR_CEPH_PREFIX, XATTR_CEPH_PREFIX_LEN) ||
+       return !strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) ||
+              !strncmp(name, XATTR_CEPH_PREFIX, XATTR_CEPH_PREFIX_LEN) ||
               !strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) ||
               !strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN);
 }
@@ -1265,35 +1266,6 @@ out:
                ceph_pagelist_release(pagelist);
        return err;
 }
-
-static int ceph_xattr_set_security_label(const struct xattr_handler *handler,
-                                   struct dentry *unused, struct inode *inode,
-                                   const char *key, const void *buf,
-                                   size_t buflen, int flags)
-{
-       if (security_ismaclabel(key)) {
-               const char *name = xattr_full_name(handler, key);
-               return __ceph_setxattr(inode, name, buf, buflen, flags);
-       }
-       return  -EOPNOTSUPP;
-}
-
-static int ceph_xattr_get_security_label(const struct xattr_handler *handler,
-                                   struct dentry *unused, struct inode *inode,
-                                   const char *key, void *buf, size_t buflen)
-{
-       if (security_ismaclabel(key)) {
-               const char *name = xattr_full_name(handler, key);
-               return __ceph_getxattr(inode, name, buf, buflen);
-       }
-       return  -EOPNOTSUPP;
-}
-
-static const struct xattr_handler ceph_security_label_handler = {
-       .prefix = XATTR_SECURITY_PREFIX,
-       .get    = ceph_xattr_get_security_label,
-       .set    = ceph_xattr_set_security_label,
-};
 #endif /* CONFIG_CEPH_FS_SECURITY_LABEL */
 #endif /* CONFIG_SECURITY */
 
@@ -1318,9 +1290,6 @@ const struct xattr_handler *ceph_xattr_handlers[] = {
 #ifdef CONFIG_CEPH_FS_POSIX_ACL
        &posix_acl_access_xattr_handler,
        &posix_acl_default_xattr_handler,
-#endif
-#ifdef CONFIG_CEPH_FS_SECURITY_LABEL
-       &ceph_security_label_handler,
 #endif
        &ceph_other_xattr_handler,
        NULL,