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Date: Sat, 11 Jul 2015 14:15:53 +0100
From: RW <rwmaillists@googlemail.com>
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Subject: Re: RFC: Pass TRIM through GELI
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On Fri, 10 Jul 2015 17:28:37 -0500
Matthew D. Fuller wrote:


> 2) Security.  For whatever your threat model is, leaking the "how much
>    space is in use" datum is unacceptable. 

It's not about how much space is free, it's about giving away which
blocks do and don't contain data.


Perhaps more importantly TRIM breaks plausible deniabily, which was
the the point of allowing the geli metadata to be store separately. You
can't argue that a partition has been wiped with 'dd if=/dev/random ...'
if the the partition has been subsequently trimmed.