NULL pointer dereference in unpack_fields (libmariadb)

libmariadb/mariadb_lib.c

    ...

    for (i=0; i < field_count; i++)

    {

      uint length= (uint)(row->data[i+1] - row->data[i] - 1);

      if (!row->data[i] && row->data[i][length])

        goto error;

    ...

Even if row->data[i] is NULL we still continue condition evaluation and dereference NULL pointer in row->data[i][length]. Possibly || should be used instead of &&.