From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ZenIV.linux.org.uk>
Subject: Re: [PATCH 1/5] WIP: Add syscall unlinkat_s (currently x86* only)
Date: Tue, 3 Feb 2015 08:10:19 +0000
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On Tue, Feb 03, 2015 at 09:01:36AM +0100, Alexander Holler wrote:
> Am 03.02.2015 um 08:56 schrieb Al Viro:
> 
> >While we are at it, "overwrite with zeroes" is too weak if the attacker
> >might get hold of the actual hardware.  Google for details - it's far too
> >long story for l-k posting.  Look for data recovery and secure data erasure...
> 
> You might read
> 
> http://link.springer.com/chapter/10.1007/978-3-540-89862-7_21
> 
> Here is an article in german about that:
> 
> http://www.heise.de/security/meldung/Sicheres-Loeschen-Einmal-ueberschreiben-genuegt-198816.html
> 
> In short, it's enough to overwrite it once with zeros,

Regardless of the media used?  How does that work on e.g. flash?