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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E141BC433EF for ; Thu, 11 Nov 2021 09:34:19 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 6A4B5610F8 for ; Thu, 11 Nov 2021 09:34:19 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 6A4B5610F8 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=nongnu.org Received: from localhost ([::1]:40414 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ml6TK-0005NV-EZ for qemu-devel@archiver.kernel.org; Thu, 11 Nov 2021 04:34:18 -0500 Received: from eggs.gnu.org ([209.51.188.92]:57074) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ml6PD-0006Cr-Kc for qemu-devel@nongnu.org; Thu, 11 Nov 2021 04:30:03 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:38438) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ml6PB-00052b-R7 for qemu-devel@nongnu.org; Thu, 11 Nov 2021 04:30:03 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1636623001; 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=z0vKcxWWrzshsuq26TpYnutdOTseWzgssH8/x8YRRsQ=; b=eJdVYsk/bUDXClIO5aph6hl1hAovy/1AAeG2v5iJZID64Rgq/gQ9CcxRyLB4WEs38unNO+ vacnptVRvoDtj+K9XEFDHgmgsfWIUfcpGOF8HF3PSKFhc2AhRwM8ZZIr1rF2b0G9+q4qzD 3D+fppZWsX2lh0/Uo7XmiOSYXKybfDE= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-88-lbxf0NTPMia5whBi2tmd7w-1; Thu, 11 Nov 2021 04:29:58 -0500 X-MC-Unique: lbxf0NTPMia5whBi2tmd7w-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id CC3A5875048; Thu, 11 Nov 2021 09:29:56 +0000 (UTC) Received: from redhat.com (unknown [10.39.193.115]) by smtp.corp.redhat.com (Postfix) with ESMTPS id D527A60C0F; Thu, 11 Nov 2021 09:29:47 +0000 (UTC) Date: Thu, 11 Nov 2021 09:29:44 +0000 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Dov Murik Subject: Re: [PATCH v2 4/6] target/i386/sev: Fail when invalid hashes table area detected Message-ID: References: <20211108134840.2757206-1-dovmurik@linux.ibm.com> <20211108134840.2757206-5-dovmurik@linux.ibm.com> MIME-Version: 1.0 In-Reply-To: <20211108134840.2757206-5-dovmurik@linux.ibm.com> User-Agent: Mutt/2.0.7 (2021-05-04) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=berrange@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -34 X-Spam_score: -3.5 X-Spam_bar: --- X-Spam_report: (-3.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.7, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 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?= Cc: Tom Lendacky , Ashish Kalra , Brijesh Singh , Eduardo Habkost , Eric Blake , James Bottomley , Marcelo Tosatti , qemu-devel@nongnu.org, "Dr. David Alan Gilbert" , Tobin Feldman-Fitzthum , Gerd Hoffmann , Paolo Bonzini , Philippe =?utf-8?Q?Mathieu-Daud=C3=A9?= , Markus Armbruster Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Mon, Nov 08, 2021 at 01:48:38PM +0000, Dov Murik wrote: > Commit cff03145ed3c ("sev/i386: Introduce sev_add_kernel_loader_hashes > for measured linux boot", 2021-09-30) introduced measured direct boot > with -kernel, using an OVMF-designated hashes table which QEMU fills. > > However, no checks are performed on the validity of the hashes area > designated by OVMF. Specifically, if OVMF publishes the > SEV_HASH_TABLE_RV_GUID entry but it is filled with zeroes, this will > cause QEMU to write the hashes entries over the first page of the > guest's memory (GPA 0). > > Add validity checks to the published area. If the hashes table area's > base address is zero, or its size is too small to fit the aligned hashes > table, display an error and stop the guest launch. In such case, the > following error will be displayed: > > qemu-system-x86_64: SEV: guest firmware hashes table area is invalid (base=0x0 size=0x0) > > Signed-off-by: Dov Murik > Reported-by: Brijesh Singh > --- > target/i386/sev.c | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) Reviewed-by: Daniel P. Berrangé 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 :|