Skip site navigation (1)Skip section navigation (2)
Date:      Sun, 05 Jun 2016 13:19:00 +0000
From:      bugzilla-noreply@freebsd.org
To:        freebsd-bugs@FreeBSD.org
Subject:   [Bug 210049] jails & the default  lo0 127.0.0.1 loopback interface
Message-ID:  <bug-210049-8@https.bugs.freebsd.org/bugzilla/>

next in thread | raw e-mail | index | archive | help
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D210049

            Bug ID: 210049
           Summary: jails & the default  lo0 127.0.0.1 loopback interface
           Product: Base System
           Version: 10.3-RELEASE
          Hardware: Any
                OS: Any
            Status: New
          Severity: Affects Many People
          Priority: ---
         Component: kern
          Assignee: freebsd-bugs@FreeBSD.org
          Reporter: qjail1@a1poweruser.com

The undocumented behavior of non-vimage jails populated with an port or pkg
that defaults to communicating over the lo0 127.0.0.1 loopback interface is=
 to
simply map it over with the jails defined primary IP address. This default =
jail
behavior exposes that port/pkg to all the traffic entering the jail over its
primary IP address whether from the LAN or public network. This is a securi=
ty
issue.=20

This is not the behavior of 127.0.0.1 as defined in [RFC1700, page 5] which
states  "127.0.0.0/8 - This block is assigned for use as the Internet host=
=20=20
loopback address. A datagram sent by a higher level protocol to an address
anywhere within this block should loop back inside the host."  In a jails c=
ase
the word "host" would also mean "jail".

The administrators of such jails have to manually activate loopback by addi=
ng
lo0:127.0.0.x to the jails ip4_addr parameter value alone with the jails
primary IP address. Then manually change the conf file of all the applicati=
ons
running in that jail to use that lo0 127.0.0.x IP address. Or an alternate =
is
to add a statement to the hosts rc.conf to clone the lo0 interface and them
code as above. This means each jail has a unique loopback ip address.=20

This manual work around is not documented and should not be necessary. The
non-vimage jail should just handle loopback localhost by default. The kernel
lo0 interface needs to be made jail aware.

This issue has been recently discussed with James Gritton jamie@freebsd.org=
 and
he agrees its time to address this long outstanding security issue.

--=20
You are receiving this mail because:
You are the assignee for the bug.=



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?bug-210049-8>