linux-kernel - How to hack syscall-table, in kernel 2.6+ ?

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Message-ID: <CAHP4M8WV64UMor_oU4UNgGx7P0Zet_M3yJrAZaCR+yYQmmeEYw@mail.gmail.com>
Date:	Tue, 14 Aug 2012 17:01:56 +0530
From:	Ajay Garg <ajaygargnsit@...il.com>
To:	linux-kernel@...r.kernel.org
Subject: How to hack syscall-table, in kernel 2.6+ ?

Hi all.

It is well known that the syscall-table had stopped being exported
from version 2.6 onwards.

So, now as a developer, if I wish to hack into the syscall-table, and
change the syscall-function-pointers to my custom-function-pointers
(mainly for the reason of adding/preventing access to certain files,
via Kernel-Loadable-Modules), what is the recommended way?

I have already tried extracting the address of the "sys_call_table"
from "System.Map"; however, I am still not able to replace the
function-pointers with mine.
Trying to do gives me page-faults, apparently meaning that the
syscall-table memory area is read-only.

I will be grateful, if someone could point me to the recommended way
of doing this.

Thanks and Regards,
Ajay
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