Re: [Tails-dev] PROBLEM: memtest tests only LOWMEM

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Author: intrigeri
Date:  
To: The Tails public development discussion list
Subject: Re: [Tails-dev] PROBLEM: memtest tests only LOWMEM
Hi,

Chris wrote (26 Dec 2011 07:33:00 GMT) :
> Is this still an issue? My understanding is that there is a maximum
> of about 2 minutes before all contents of memory have "dissipated".


Keywords: cold boot attack.

> How long does it take to 'wipe' the memory?


Few seconds.

> The 2nd question is what do you call wiping?


Overwrite as much memory as we can, several times. The approach
implemented in Tails 0.9 does one pass with zeroes, as documented in
our design document. The memtest=2 approach we're considering does
3 passes.

> Doing more than one pass is probably no more effective than
> a single pass.


This is why we've been doing only one pass until now.

Given the process is very quick, and no research results about the
effectiveness of single vs. multiple passes were ever published AFAIK,
I think it also makes sense to run a few passes, just to (blindly try
to) be on the safe side.

Cheers,
--
intrigeri <intrigeri@???>
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