[8823] in bugtraq
Re: Postfix design directions
daemon@ATHENA.MIT.EDU (Chris Adams)
Thu Dec 24 21:18:43 1998
Date: Wed, 23 Dec 1998 14:35:12 -0600
Reply-To: Bugtraq List <BUGTRAQ@NETSPACE.ORG>
From: Chris Adams <cadams@RO.COM>
To: BUGTRAQ@NETSPACE.ORG
In-Reply-To: <19981222200230.6E97245901@spike.porcupine.org>; from Wietse
Venema on Tue, Dec 22, 1998 at 03:02:30PM -0500
Once upon a time, Wietse Venema <wietse@PORCUPINE.ORG> said:
> Attack 2 is a wash. Postfix deletes a queue file that has multiple
> links, so that the link count goes down; Postfix delivers a queue
> file that has one hard link and that satisfies the Postfix-specific
> record structure and record sequence requirements; Postfix discards
> any other queue file.
Seems like there could be race conditions here too. For example, if you
check the link count, and if it is 1, process the file and unlink it,
someone could wait until you are processing the file to create a hard
link to it. Then, after you unlinked the first copy, the second copy
would again have a link count of 1.
--
Chris Adams - cadams@ro.com
System Administrator - Renaissance Internet Services
I don't speak for anybody but myself - that's enough trouble.
