- Problem: data separators were copied to a fixed-size buffer
  on the stack; memcpy was used, without bounds checking; a
  server crash could result if long FIELDS ENCLOSED BY, etc.,
  was given
- Fix: write the separators directly, instead of copying to
  a buffer first (in select_export::send_data())


sql/sql_class.cc:
  In select_export::send_data(), write data separators
  directly, instead of copying into a fixed-size memory
  buffer before writing.  This avoids a buffer overflow
  when very large separators are specified.