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From: "Robert N. M. Watson" <rwatson@freebsd.org>
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To: Jilles Tjoelker <jilles@stack.nl>
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Subject: Re: "ps -e" without procfs(5)
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On 4 Dec 2011, at 14:31, Jilles Tjoelker wrote:

> On Sat, Oct 29, 2011 at 01:32:39PM +0300, Mikolaj Golub wrote:
>> [KERN_PROC_AUXV requires just p_cansee()]
>=20
> If we are ever going to do ASLR, the AUXV information tells an =
attacker
> where the stack, executable and RTLD are located, which defeats much =
of
> the point of randomizing the addresses in the first place.
>=20
> Given that the AUXV information seems to be used by debuggers only
> anyway, I think it would be good to move it to p_candebug() now.
>=20
> The full virtual memory maps (KERN_PROC_VMMAP, procstat -v) are =
already
> under p_candebug().


Agreed. In general, my view is that p_cansee() should be used for very =
few of our process inspection APIs. I like your example of ASLR =
especially, as it illustrates how debugging information can aid even =
local attacks (i.e., user vs. setuid binary).

Robert=