diff --git a/man2/mount_setattr.2 b/man2/mount_setattr.2
index 0739624cc..6ffe5e009 100644
--- a/man2/mount_setattr.2
+++ b/man2/mount_setattr.2
@@ -961,7 +961,10 @@ main(int argc, char *argv[])
     const char *source = argv[optind];
     const char *target = argv[optind + 1];
 
-    int fd_tree = open_tree(\-EBADF, source,
+    /* In the following, \-1 as the \(aqdirfd\(aq argument ensures that
+       open_tree() fails if \(aqsource\(aq is not an absolute pathname. */
+
+    int fd_tree = open_tree(\-1, source,
                        OPEN_TREE_CLONE | OPEN_TREE_CLOEXEC |
                        AT_EMPTY_PATH | (recursive ? AT_RECURSIVE : 0));
     if (fd_tree == \-1)
@@ -980,7 +983,10 @@ main(int argc, char *argv[])
 
     close(fd_userns);
 
-    ret = move_mount(fd_tree, "", \-EBADF, target,
+    /* In the following, \-1 as the \(aqto_dirfd\(aq argument ensures that
+       open_tree() fails if \(aqtarget\(aq is not an absolute pathname. */
+
+    ret = move_mount(fd_tree, "", \-1, target,
                      MOVE_MOUNT_F_EMPTY_PATH);
     if (ret == \-1)
         exit_log("%m \- Failed to attach mount to %s\en", target);