From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:35049) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YscsB-0006zp-Q8 for qemu-devel@nongnu.org; Wed, 13 May 2015 16:03:20 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Yscs8-0006EW-Ux for qemu-devel@nongnu.org; Wed, 13 May 2015 16:03:19 -0400 Message-ID: <5553ADFB.2060105@redhat.com> Date: Wed, 13 May 2015 16:03:07 -0400 From: John Snow MIME-Version: 1.0 References: <1431527602-29889-1-git-send-email-jsnow@redhat.com> <55539D17.7010000@weilnetz.de> <55539EFA.6050605@profihost.ag> <5553A07E.6070608@weilnetz.de> <5553A17D.4090308@profihost.ag> <5553A651.3060508@kamp.de> <877fsccl19.fsf@blackfin.pond.sub.org> <5553ADBF.6060005@kamp.de> In-Reply-To: <5553ADBF.6060005@kamp.de> Content-Type: text/plain; charset=iso-8859-15 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [Qemu-stable] [PATCH] fdc: force the fifo access to be in bounds of the allocated buffer List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Lieven , Markus Armbruster Cc: qemu-devel@nongnu.org, peter.maydell@linaro.org, Petr Matousek , qemu-stable@nongnu.org, Stefan Weil On 05/13/2015 04:02 PM, Peter Lieven wrote: > Am 13.05.2015 um 21:52 schrieb Markus Armbruster: >> Peter Lieven writes: >> >>> Am 13.05.2015 um 21:09 schrieb Stefan Priebe: >>>> Am 13.05.2015 um 21:05 schrieb Stefan Weil: >>>>> Am 13.05.2015 um 20:59 schrieb Stefan Priebe: >>>>>> Am 13.05.2015 um 20:51 schrieb Stefan Weil: >>>>>>> Hi, >>>>>>> >>>>>>> I just noticed this patch because my provider told me that my KVM based >>>>>>> server >>>>>>> needs a reboot because of a CVE (see this German news: >>>>>>> http://www.heise.de/newsticker/meldung/Venom-Schwachstelle-Aus-Hypervisor-ausbrechen-und-VMs-ausspionieren-2649614.html) >>>>>>> >>>>>> Isn't a live migration to a fixed version enough instead of a reboot? >>>>>> >>>>>> Stefan >>>>> Good point. A live migration would be sufficient - if there are no bugs >>>>> in QEMU's live migration. >>>> just migrating all our customer machines and wanted to be sure that >>>> live migration is enough. >>> Just to confirm: If Qemu is started with -nodefaults and there is no >>> fdc configuration the system is not affected by this CVE? >> Not true. The FD controller is still there. It has no drives attached >> then, but is vulnerable all the same. > > Are you sure? With -nodefaults the hmp command 'info block' returns nothing and > the guest sees no floppy drive. > > Without -nodefaults I indeed see floppy0 and I have /dev/fd0 in the guest respectively. > > Peter > It's not the *drive* that is the problem, it is the *controller*.