gdi32/font: Prevent possible buffer overrun

[Dmitry Timoshkov]

"Nikolay Sivov" <bunglehead at gmail.com> wrote:

> Reported as http://bugs.winehq.org/show_bug.cgi?id=19819
> 
> Changelog:
>     - prevent possible buffer overrun

> - while (!(*lpSrc>>index & 0x0001) && index<MAXTCIINDEX) index++;
> +      while (index < MAXTCIINDEX && !(*lpSrc>>index & 0x0001)) index++;

'index >= MAXTCIINDEX' won't trigger in that case:

if (index >= MAXTCIINDEX || FONT_tci[index].ciCharset == DEFAULT_CHARSET) return FALSE;

It would be simpler IMO to add one more item to FONT_tci[] instead.

-- 
Dmitry.