From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Mon, 3 Mar 2008 13:40:39 +0300 From: "Dmitry V. Levin" To: ALT Linux Team development discussions Message-ID: <20080303104038.GB3425@wo.int.altlinux.org> Mail-Followup-To: ALT Linux Team development discussions References: <20070913231033.GC3619@basalt.office.altlinux.org> <20070917091229.GB10677@localhost.localdomain> <20070917172128.GB25433@basalt.office.altlinux.org> <20070917173545.GA10916@localhost.localdomain> <20070918214009.GB19447@basalt.office.altlinux.org> <20070919131433.GA373@localhost.localdomain> <20070919131950.GD13831@basalt.office.altlinux.org> <20070919133003.GA26869@localhost.localdomain> <20070919135301.GF13831@basalt.office.altlinux.org> <20080303103815.GA5098@localhost.localdomain> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="yEPQxsgoJgBvi8ip" Content-Disposition: inline In-Reply-To: <20080303103815.GA5098@localhost.localdomain> X-fingerprint: FE4C 93AB E19A 2E4C CB5D 3E4E 7CAB E6AC 9E35 361E Subject: Re: [devel] nologin X-BeenThere: devel@lists.altlinux.org X-Mailman-Version: 2.1.10b3 Precedence: list Reply-To: ALT Linux Team development discussions List-Id: ALT Linux Team development discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 03 Mar 2008 10:40:39 -0000 Archived-At: List-Archive: List-Post: --yEPQxsgoJgBvi8ip Content-Type: text/plain; charset=koi8-r Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Mar 03, 2008 at 12:38:15PM +0200, Kirill A. Shutemov wrote: > On [Wed, 19.09.2007 17:53], Dmitry V. Levin wrote: > > On Wed, Sep 19, 2007 at 04:30:03PM +0300, Kirill A. Shutemov wrote: > > > On [Wed, 19.09.2007 17:19], Dmitry V. Levin wrote: > > > > On Wed, Sep 19, 2007 at 04:14:33PM +0300, Kirill A. Shutemov wrote: > > [...] > > > > > nologin.c: Rewrite without glibc at all (#10729) > > > > >=20 > > > > > =EE=C5 =D3=CF=D7=D3=C5=CD =D0=CF=CE=D1=D4=CE=CF =DA=C1=DE=C5=CD = =C9 =CB=C1=CB =DC=D4=CF =CD=CF=C7=CC=CF =D0=CF=C6=C9=CB=D3=C9=D4=D8 =C2=C1= =C7. =ED=CF=D6=CE=CF =CC=C9 =D7=C5=D2=CE=D5=D4=D8 > > > > > =CF=C2=D2=C1=D4=CE=CF glibc? > > > >=20 > > > > =E5=D3=CC=C9 =D7=C5=D2=CE=D5=D4=D8 =CF=C2=D2=C1=D4=CE=CF glibc, =D4= =CF =D7=C5=D2=CE=A3=D4=D3=D1 #10729. > > >=20 > > > =E1 =DE=D4=CF =D1=D7=CC=D1=C5=D4=D3=D1 =D0=D2=C9=DE=C9=CE=CF=CA =DC= =D4=CF=C7=CF =C2=C1=C7=C1? > >=20 > > =EE=C5=D0=D2=C1=D7=C9=CC=D8=CE=C1=D1 =D3=D4=C1=D4=C9=DE=C5=D3=CB=C1=D1 = =CC=C9=CE=CB=CF=D7=CB=C1 =C2=C5=DA libc. >=20 > =E5=D3=CC=C9 =D3=CF=C2=D2=C1=D4=D8 =D3 -nostartfiles =CE=C5 =D3=D4=C1=D4= =C9=CB=CF=CA, =D2=C9=D3=CB =D3=CF=C8=D2=C1=CE=C9=D4=D3=D1?=20 =E5=D3=CC=C9 =D3=CF=C8=D2=C1=CE=C9=D4=D8 dynamic linker, =D4=CF =D3=CF=C8= =D2=C1=CE=C9=D4=D3=D1. =F2=C1=DA=D7=C5 =DE=D4=CF =D3=C4=C5=CC=C1=D4=D8 nologin sgid'=CE=D9=CD. =EE=CF =D2=C1=CE=D8=DB=C5 =C2=D9=CC=CF =D0=D2=CF=DD=C5 =D3=CC=C9=CE=CB=CF= =D7=C1=D4=D8 nologin =D3=D4=C1=D4=C9=DE=C5=D3=CB=C9. > > =FA=C1=DE=C5=CD =CE=D5=D6=CE=CF =CC=C9=CE=CB=CF=D7=C1=D4=D8 nologin =C2= =C5=DA libc? =F0=D2=C9=D7=C5=C4=D5 =C3=C9=D4=C1=D4=D5 (=CC=C5=CE=D8 =D0=C5= =D2=C5=D7=CF=C4=C9=D4=D8): > >=20 > > "The dynamic linker and libc startup code checks a number of environment > > variables, which may seriously alter the behavior of the starting > > program - up to execution of arbitrary code (other than that found in > > the program). Login services such as telnetd/login and sshd allow for > > initial environment variables to be passed from the remote. This has > > actually been used to break into systems in the past. > >=20 > > Now, modern/patched versions of login services use whitelists of > > known-safe environment variables - and allow only for those environment > > variables to be passed from the remote. > >=20 > > But we can feel a little bit safer if our disabled accounts' "shells" > > would not be subject to this risk at all - and the only currently > > practical way to achieve that is to avoid the use of the dynamic linker > > and libc." --=20 ldv --yEPQxsgoJgBvi8ip Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.8 (GNU/Linux) iEUEARECAAYFAkfL1aYACgkQfKvmrJ41Nh49GgCeKQkX52Sg4NnedBY8w20Yibha ZN4AlRtkJMXhq6tCBpsOBwgvuFoZTdk= =tnmF -----END PGP SIGNATURE----- --yEPQxsgoJgBvi8ip--