From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hans Reiser Subject: Re: securely deleting files Date: Mon, 12 May 2003 14:39:51 +0400 Message-ID: <3EBF79F7.8090501@namesys.com> References: <20030512075022.GC21604@namesys.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: list-help: list-unsubscribe: list-post: Errors-To: flx@namesys.com In-Reply-To: <20030512075022.GC21604@namesys.com> List-Id: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: Oleg Drokin Cc: Jason Holt , reiserfs-list@namesys.com Oleg Drokin wrote: >Hello! > >On Tue, May 06, 2003 at 05:37:13AM +0000, Jason Holt wrote: > > > >>Now, a good friend of mine pointed out that part of the space on a filesystem >>is kept aside just for root, so you may want to fill the disk up as root. >>(Is this actually a concern? Can blocks which used to hold user data end up >>being reserved?) >> >> > >Yes they can. >No, we don't have such (supported) feature in reiserfsv3 yet. > You meant the reserved space for root? >Also if the file was deleted, but something still have open filehandle to it (or hardlink), >its blocks are not freed at rm time and therefore filling all the free space won't help. >There are other caveats. > > > >>Also, if your sensitive file was in memory recently it might have been swapped >>out, in which case it may still be in the swap partition. I have a program >>which fills up all available *memory* as well, and I could post the source >>here if everyone's interested. >> >> > >If the program that used the file and still have the copy of it is still running, >no matter how much you eat all the ram, the file still can end up in swap. > >The program that fills up all available memory is called "tail". Just run >"tail /dev/zero" and enjoy ;) (this does not work on FreeBSD, though). > >Bye, > Oleg > > > > -- Hans