From owner-freebsd-jail@freebsd.org Mon Dec 12 14:40:51 2016 Return-Path: Delivered-To: freebsd-jail@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id E495FC7308D for ; Mon, 12 Dec 2016 14:40:51 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2001:1900:2254:206a::16:76]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id CD8051618 for ; Mon, 12 Dec 2016 14:40:51 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from bugs.freebsd.org ([127.0.1.118]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id uBCEepBa042726 for ; Mon, 12 Dec 2016 14:40:51 GMT (envelope-from bugzilla-noreply@freebsd.org) From: bugzilla-noreply@freebsd.org To: freebsd-jail@FreeBSD.org Subject: [Bug 215250] jail break under particular circumstance Date: Mon, 12 Dec 2016 14:40:52 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: kern X-Bugzilla-Version: 11.0-STABLE X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Many People X-Bugzilla-Who: jamie@FreeBSD.org X-Bugzilla-Status: Closed X-Bugzilla-Resolution: Works As Intended X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: freebsd-jail@FreeBSD.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: cc resolution bug_status Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: freebsd-jail@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: "Discussion about FreeBSD jail\(8\)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 12 Dec 2016 14:40:52 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D215250 Jamie Gritton changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |jamie@FreeBSD.org Resolution|--- |Works As Intended Status|New |Closed --- Comment #2 from Jamie Gritton --- Yes, it's expected behavior. It's not so much a "break" as being pulled ou= t of the jail by an administrator with proper permission who presumably knows wh= at he's doing. Preventing an assisted break like this would be doable, but would involve either tracing all .. traversals back to at least a prison root, or attachi= ng a prison reference to every directory in the vnode cache. Both of those seem= to be a bit of overkill. I have to admin I've done the very thing in the example: temporarily moving /usr/ports to a jail. Lately I've gone with nullfs instead, which doesn't = open this hole. --=20 You are receiving this mail because: You are the assignee for the bug.=