To me it looks like a duplicate/regression of bug #402884 since the os0file.c fix to change os_file_handle_error to os_file_handle_error_no_exit appears to be missing from current xtrabackup.
To me it looks like a duplicate/ regression of bug #402884 since the os0file.c fix to change os_file_ handle_ error to os_file_ handle_ error_no_ exit appears to be missing from current xtrabackup.