Re: shell code on minix

Sridhar wrote:
I installed gcc3.4 on minix3.1.2a which compiles the program without
errors which implies that symbol table construction by the two
compilers may be different.

The program however fails with a "Memory fault- core dumped". Does
that mean that stack is not executable? Again, any piece of code/
literature will be great.

I wonder if that piece of code really works as you expect.

The stack (or data) segment in a i386 processor are not executable and analyzing in details the assembler generated in the Minix and Linux you may see what trick are used and why it works on Linux. I'm sorry, but I.m not familiar with gcc assembler.

It doubt that the compiler is so smart that it changes the segment descriptors (it won't work) but I suppose that it may use some capability of the ELF format used in Linux.

The stack segment could be described twice. As stack and as text segment. The Minix format does not have such feature.

Reading any book on the i386 family of processors would be of help to understand how memory protection and allocation works.

Ciao
Giovanni
--
A computer is like an air conditioner,
it stops working when you open Windows.
Registered Linux user #337974 < http://giovanni.homelinux.net/ >
.

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