Who will be the last HD maker down the road? - test-drb@ccmp.vtda.org

9 Mar 2011

On Wed, 09 Mar 2011 15:30:30 -0600
cctalk-request at classiccmp.org wrote:

...
   On Tue, 08 Mar
2011 18:14:38 -0600
 cctalk-request at classiccmp.org wrote:

  From: Richard <legalize at xmission.com>
 Subject: Re: Who will be the last HD maker down the road?
 To: cctalk <cctalk at classiccmp.org>
 Message-ID: <E1Px1RU-000789-Ic at shell.xmission.com>

 In article <4D75366B.21696.2604652 at cclist.sydex.com>,
     "Chuck Guzis" <cclist at sydex.com> writes:

  We may be using flash both for external storage
and internal
 storage.       
 Flash memory is problematic for secure data.  Basically, its nearly
 impossible to securely erase a file from flash based disks.    
 I don't know how that can be true. I can understand deleting doesn't
 work but is it true a simple dd if=/dev/zero of=/dev/sdx onto the flash
 card doesn't fill it with zeros?    
 You can't use dd to erase an individual file. 
You don't have to and that's not the point. The point is you can make a
flash drive unrecoverable using dd.

If you want individual files to be unrecoverable, just encrypt the whole
flash device and never write anything to it in the clear. Easy to implement
and a good general solution.

...
  In addition, there are all the machinations that Al
mentioned.  The device
 pretends to be a disk, but it isn't a disk. 
Doesn't matter as far as I can tell. It has to store the data you give it
somewhere, or it wouldn't be useful. Therefore you can get it to overwrite
whats already there, just not at the filesystem level.