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Date: Thu, 30 Sep 2010 18:04:05 +0800
From: =?utf-8?Q?Am=C3=A9rico?= Wang <xiyou.wangcong@gmail.com>
To: Andreas Saebjoernsen <andreas@digitalplaywright.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: interpreting semantics of ipc system call
Message-ID: <20100930100405.GB5265@cr0.nay.redhat.com>
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On Wed, Sep 29, 2010 at 03:03:11PM -0700, Andreas Saebjoernsen wrote:
>We are developing a simulator that can simulate any specimen x86 linux program.
>Our simulator has a simulated memory, unlike the concrete memory state of
>tools like Valgrind, so that we can do concrete symbolic execution. Instead of
>reimplementing the system calls we marshal the system calls called by
>the specimen.
>
>I am currently working on marshaling calls to the ipc system call (system
>call 117) which has the following signature
>
>int ipc(unsigned int call, int first, int second, int third, void
>*ptr, long fifth)
>
>I have a problem interpreting what the size is of the data structure
>pointed to by
>the 'void*', and I have been unable to locate good documentation or code on the
>semantics of this system call.


Take a look at ipc/syscall.c, that pointer will be interpreted to different
data structures when you pass different arguments to 'call'.