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Date: Mon, 08 Apr 2013 23:18:52 -0700
From: Xin Li <delphij@delphij.net>
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To: freebsd-hackers@freebsd.org
Subject: Re: copyinstr()
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On 4/8/13 6:15 PM, Vijay Singh wrote:
> Hi, I was looking for some help with copyinstr() on an amd64
> platform.
> 
> My from address happens to be in the kernel (stack). I am getting
> an EFAULT, and I am wondering how to fix that.

Since you are doing a copy*in*str, I think "from" address would be the
uaddr?  In that case, it should be a userland address...

> Would using memory from malloc() make a difference?

Maybe not...  EFAULT means the address is not valid.

Cheers,
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