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From: John Baldwin <jhb@freebsd.org>
To: freebsd-hackers@freebsd.org, John-Mark Gurney <gurney_j@resnet.uoregon.edu>
Date: Tue, 28 Feb 2006 13:33:47 -0500
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Cc: Tanmay <tanmayinamdar@gmail.com>
Subject: Re: Accessing address space of a process through kld!!
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On Monday 27 February 2006 13:31, John-Mark Gurney wrote:
> Tanmay wrote this message on Mon, Feb 27, 2006 at 13:56 +0530:
> > How do I access the address space ie text,data and stack of a (user
> > level)process whose pid I know from my kld. for eg: Suppose 'vi' is running
> > and I want to access its address space through my kld, then how do I do it?
> 
> You look up the process with pfind(9), and then you can use uio(9) to
> transfer data into kernel space...  Don't forget to PROC_UNLOCK the
> struct once you are done referencing it.

You can use the proc_rwmem() function (it takes a uio and a struct proc)
to do the actual I/O portion.  You can see example use in the ptrace()
syscall.

-- 
John Baldwin <jhb@FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve"  =  http://www.FreeBSD.org