Re: Virus Checking - COMPLETELY UNENCUMBERED!
On Wed 15 May 2002 at 09:05:32 +0300, Richard Braakman wrote:
> On Tue, May 14, 2002 at 08:41:11PM -0700, Luca Filipozzi wrote:
> > > Or tried to feed a .bz2 from 2 gigabytes of zeroes through an amavis
> > > with an unpacking partition of 150MB.
> >
> > That's interesting. Good thing I limit mail messages to 10MB with the
> > MTA, I guess.
>
> That might not help. Gigabytes of zeroes compress really well :)
> The actual .bz2 file can be under your 10MB limit, and still fill up
> any partition you try to unpack it in. So the virus scanner needs
> to be smart enough to deal with this.
For example:
$ cat /dev/zero | head -c 2147483647 | bzip2 -9 | wc -c
1522
$
For decompressors which can operate in a pipe (like bzip2, gzip), is
there anything much wrong with doing the decompressing something like
this:
$ cat $TMPFILE | bzcat | head -c $SIZELIMIT > $TMPFILEOUT
? Of course it will corrupt (by truncating) attachments which are zipped
files of zeros, but is that a problem?
Tim.
--
Tim Bell - bhat@trinity.unimelb.edu.au - System Administrator & Programmer
Trinity College, Royal Parade, Parkville, Victoria, 3052, Australia
--
To UNSUBSCRIBE, email to debian-devel-request@lists.debian.org
with a subject of "unsubscribe". Trouble? Contact listmaster@lists.debian.org
Reply to: