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From: =?iso-8859-1?q?Lu=EDs=20Henriques?= 
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To: Anton Altaparmakov <aia21@cam.ac.uk>, <linux-kernel@vger.kernel.org>
Subject: Re: copy to suer space
Date: Tue, 20 Nov 2001 17:08:52 +0000
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> I don't think what you are trying to do is possible. Even if you somehow
> managed to write over the code segment of a user space process (which I
> very much doubt would be possible as I assume the memory is mapped
> read-only)

Is there a way to solve this problem? To temporarly turn it read/write?

>, as soon as the kernel pages out (i.e. discards!) some portion
> of the executable due to memory shortage your changes would be lost, since
> the paging back into memory would happen by reading the executable back
> from disk, which would mean it would read the unmodified code into
> memory...

When I'm modifing the code, I'm sure that the page is in memory because my 
code is called from the user space, in the exact location where I want to 
change it (with a breakpoint interruption...)

The point is that I can't write to the memory location I want... How do I 
solve this?

-- 
Lu?s Henriques
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