Date:	Thu, 13 Jan 2000 17:42:30 +0200 (IST)
From:	Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
X-Sender:	eliz AT is
To:	Martin Stromberg <eplmst AT lu DOT erisoft DOT se>
cc:	djgpp AT delorie DOT com
Subject:	Re: Problems with protected_mode_int
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On 13 Jan 2000, Martin Stromberg wrote:

> asm("
> my_handler:
> ...
> 
> my_handler_end:
> ");
> 
> int main()
> {
>   unsigned char code[1000];
> 
>   memcpy(code, &my_handler, my_handler_end - my_handler);

This will most probably crash, for several good reasons:

  - stack is allocated off the DS selector whose access rights forbid 
    executing any address accessed via that selector;

  - the only segment register that is guaranteed to be loaded with the 
    application's selector is CS, so you cannot trust SS.

- Raw text -