From owner-freebsd-security Sun Sep 26 16: 1:39 1999 Delivered-To: freebsd-security@freebsd.org Received: from bekool.com (ns2.netquick.net [216.48.34.2]) by hub.freebsd.org (Postfix) with ESMTP id 2C9F414C25; Sun, 26 Sep 1999 16:01:34 -0700 (PDT) (envelope-from trouble@hackfurby.com) Received: from angelsguardian.netquick.net ([199.72.47.239] helo=hackfurby.com) by bekool.com with esmtp (Exim 3.03 #1) id 11VNb5-0008Zg-00; Sun, 26 Sep 1999 23:20:48 +0000 Message-ID: <37F00602.96D098D3@hackfurby.com> Date: Mon, 27 Sep 1999 19:04:19 -0500 From: TrouBle Reply-To: trouble@hackfurby.com X-Mailer: Mozilla 4.61 [en] (X11; I; FreeBSD 3.3-RELEASE i386) X-Accept-Language: en MIME-Version: 1.0 To: Carol Deihl Cc: freebsd-security@FreeBSD.ORG, freebsd-hackers@FreeBSD.ORG Subject: Re: chroot could chdir? (was Re: about jail) References: <199909251302.RAA58030@grendel.sovlink.ru> <19990925171712.A80535@zenon.net> <37EEA27E.244DCF9A@tinker.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-security@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org Ummm sorry but i think you have goten this backwards it is more secure to chdir, then chrrot, not chroot then chdir.... I believe what you have here is backwards > > As we all know, the chroot can be escaped because the sample > program doesn't change the current working directory, and it's > still pointing outside the chrooted area. > > What if chroot itself chdir'ed to it's new root directory? Would > this break existing programs? I'd expect that well-behaved > programs would chdir someplace useful before continuing anyway. > > At the very end of chroot(), could it just > vrele(fdp->fd_cdir); > fdp->fd_cdir = nd.ni_vp; > before it returns, setting the current dir to the same place it > just chrooted to? > > Carol > -- > Carol Deihl - principal, Shrier and Deihl - mailto:carol@tinker.com > Remote Unix Network Admin, Security, Internet Software Development > Tinker Internet Services - Superior FreeBSD-based Web Hosting > http://www.tinker.com/ > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-security" in the body of the message To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-security" in the body of the message