From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 5863CC43334 for ; Mon, 20 Jun 2022 10:09:29 +0000 (UTC) Received: from localhost ([::1]:36602 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1o3ELX-0000gN-6C for qemu-devel@archiver.kernel.org; Mon, 20 Jun 2022 06:09:28 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:43034) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1o3EIf-0007Be-TI for qemu-devel@nongnu.org; Mon, 20 Jun 2022 06:06:29 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:24416) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1o3EId-0005Vk-6y for qemu-devel@nongnu.org; Mon, 20 Jun 2022 06:06:28 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1655719586; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=L5RKrfPpYYRSdPHBPwdJLW/eVR7eHBYdoYlkUvyWejQ=; b=ARZt8he8Ht+DjLED5zx4ygoBncXkd7uCrndj3OO0JC0pn+UEvoxjM3wDubRvtA1G+nYBqP MuC1+UvOoI5gMAC3Pi+O72psN2SCBgnuE7BlBE2Y+8lTHcAsBQsgsbCWsq5E1CuP/I6IML OW6dgGJu3QDHLa2eCPiHN8UB46DFwFc= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-363-cStsaEA_Pai9h9ATPzaSbA-1; Mon, 20 Jun 2022 06:06:23 -0400 X-MC-Unique: cStsaEA_Pai9h9ATPzaSbA-1 Received: from smtp.corp.redhat.com (int-mx10.intmail.prod.int.rdu2.redhat.com [10.11.54.10]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id D078E80013E; Mon, 20 Jun 2022 10:06:22 +0000 (UTC) Received: from redhat.com (unknown [10.33.36.144]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 050A940314B; Mon, 20 Jun 2022 10:06:21 +0000 (UTC) Date: Mon, 20 Jun 2022 11:06:19 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: =?utf-8?Q?Marc-Andr=C3=A9?= Lureau Cc: selinux@lists.fedoraproject.org, QEMU , rmetrich@redhat.com Subject: Re: qemu-ga guest-exec & SELinux Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/2.2.1 (2022-02-19) X-Scanned-By: MIMEDefang 2.85 on 10.11.54.10 Received-SPF: pass client-ip=170.10.129.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -28 X-Spam_score: -2.9 X-Spam_bar: -- X-Spam_report: (-2.9 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.082, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Mon, Jun 20, 2022 at 01:44:05PM +0400, Marc-André Lureau wrote: > Hi! > > https://bugzilla.redhat.com/show_bug.cgi?id=2093355 ("AVCs when trying to > execute a command through qemu-ga ("guest-exec" command)") describes an > issue with fedora/rhel SELinux rules, where some program executions are > denied. > > qemu-ga has "virt_qemu_ga_t" context, and is not allowed to execute > binaries that are not "bin_t", iiuc. The suggestion from Renaud Métrich is > for qemu-ga exec command to launch the user program through an helper > program that would have the virt_qemu_ga_unconfined_exec_t context, and > appropriate rules in selinux (similar to fsfreeze-hook rules), so any > program can be executed. qemu-ga would thus ship and use that helper, in > all OS, to avoid varying code paths. > > Does that sound reasonable or should we try to find a solution with SELinux > rules instead? I thought was did not allow qemu-ga to execute binaries at all, regardless of whether they're bin_t or not. The 'guest-exec' command is essentially a giant hole that defeats the purpose of confining qemu-ga with SELinux at all IMHO. IMHO execution of external commands should only be allowed after toggling a SELinux boolean tunable. With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|