From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37849) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XkDl4-0005MJ-Oe for qemu-devel@nongnu.org; Fri, 31 Oct 2014 11:05:16 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XkAJf-0002uj-8e for qemu-devel@nongnu.org; Fri, 31 Oct 2014 07:24:33 -0400 Received: from mx1.redhat.com ([209.132.183.28]:37657) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XkAJf-0002tX-0s for qemu-devel@nongnu.org; Fri, 31 Oct 2014 07:24:27 -0400 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id s9VBOPcr010610 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL) for ; Fri, 31 Oct 2014 07:24:25 -0400 Date: Fri, 31 Oct 2014 11:24:23 +0000 From: Stefan Hajnoczi Message-ID: <20141031112423.GE10332@stefanha-thinkpad.redhat.com> References: <1414512220-19058-1-git-send-email-armbru@redhat.com> <1414512220-19058-3-git-send-email-armbru@redhat.com> <5452001E.9070907@redhat.com> <20141030092722.GB30746@stefanha-thinkpad.redhat.com> <20141030093635.GB9097@noname.str.redhat.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="HeFlAV5LIbMFYYuh" Content-Disposition: inline In-Reply-To: <20141030093635.GB9097@noname.str.redhat.com> Subject: Re: [Qemu-devel] [PATCH RFC 2/2] block: Warn on insecure format probing List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Kevin Wolf Cc: qemu-devel@nongnu.org, jcody@redhat.com, Markus Armbruster , Max Reitz --HeFlAV5LIbMFYYuh Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Oct 30, 2014 at 10:36:35AM +0100, Kevin Wolf wrote: > Am 30.10.2014 um 10:27 hat Stefan Hajnoczi geschrieben: > > The guest may legitimately use raw devices that contain image format > > data. Imagine tools similar to libguestfs. > >=20 > > It's perfectly okay for them to lay out image format data onto a raw > > device. > >=20 > > Probing is the problem, not putting image format data onto a raw device. >=20 > Agreed, that's why any restrictions only apply when probing was used to > detect a raw image. If you want to do anything exotic like storing a > qcow2 image for nested virt on a disk that is a raw image in the host, > then making sure to pass format=3Draw shouldn't be too much. Because at that point the solution is way over-engineered. Probing checks should be in the QEMU command-line code, not sprinkled across the codebase and even at run-time. Isn't Markus approach much simpler and cleaner? Stefan --HeFlAV5LIbMFYYuh Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQEcBAEBAgAGBQJUU3FnAAoJEJykq7OBq3PIfSkH/0OnVz6ID4nMulBAfKcUFPEW rfMM2ttlcBm9/B/GxwD2/j0Rw1adQK3wUKAWcObYfjr/d6wPEDQD3rOGLkRnTV9B FLU4znM/i9IWu/t/H3/TL8ZnK8QuuHTxxgfvRE71el2PCHWW8Dwt4bn9yURBEH6Y J94WrKNqk2YHOVdq/J60YUf82HhfYCbjJTCgS+86SzkM/9r+N1HFCpIRgut6/rIm ePrk0FsxQXs3apv0Tlf6McUFj0oL9nCQpsIqmIsUuAnY3zQzDjE4CQEUmLi4WCeb 68NP8iJCTpiW7zpKwslvHA/VUn5wz6T0A27Q+NRx1gMGIc5WdiVIQD4CYk2SCJs= =mIhp -----END PGP SIGNATURE----- --HeFlAV5LIbMFYYuh--