From patchwork Tue Feb 4 20:29:38 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Cooper X-Patchwork-Id: 11365247 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 96DBB921 for ; Tue, 4 Feb 2020 20:31:31 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 7261A2082E for ; Tue, 4 Feb 2020 20:31:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=citrix.com header.i=@citrix.com header.b="PDuivNxn" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7261A2082E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=citrix.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1iz4pR-0002s7-Ip; Tue, 04 Feb 2020 20:29:49 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1iz4pQ-0002s2-6n for xen-devel@lists.xenproject.org; Tue, 04 Feb 2020 20:29:48 +0000 X-Inumbo-ID: 157d8964-478d-11ea-8396-bc764e2007e4 Received: from esa4.hc3370-68.iphmx.com (unknown [216.71.155.144]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id 157d8964-478d-11ea-8396-bc764e2007e4; Tue, 04 Feb 2020 20:29:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=citrix.com; s=securemail; t=1580848187; h=from:to:cc:subject:date:message-id:mime-version; bh=TTERVOZ9S/iNOlyJqrXR0pdx6zWgIYGbMEwNZesUB94=; b=PDuivNxnf1hLpBmL2EWLJyujqH/iPEliCsdy8WHxPeIql4LNHmJ3C4ox +B3Ns+YNU7dum+Q6FFAW/8OnsPxYDX+mjFTAenZqVPL0qWeZxxYL1zKId QEkY1rD4eHsz0x0o/z9X9stRaOu84oV+RALUITI6EsH8Yd2PQa4hEuYfY I=; Authentication-Results: esa4.hc3370-68.iphmx.com; dkim=none (message not signed) header.i=none; spf=None smtp.pra=andrew.cooper3@citrix.com; spf=Pass smtp.mailfrom=Andrew.Cooper3@citrix.com; spf=None smtp.helo=postmaster@mail.citrix.com Received-SPF: None (esa4.hc3370-68.iphmx.com: no sender authenticity information available from domain of andrew.cooper3@citrix.com) identity=pra; client-ip=162.221.158.21; receiver=esa4.hc3370-68.iphmx.com; envelope-from="Andrew.Cooper3@citrix.com"; x-sender="andrew.cooper3@citrix.com"; x-conformance=sidf_compatible Received-SPF: Pass (esa4.hc3370-68.iphmx.com: domain of Andrew.Cooper3@citrix.com designates 162.221.158.21 as permitted sender) identity=mailfrom; client-ip=162.221.158.21; receiver=esa4.hc3370-68.iphmx.com; envelope-from="Andrew.Cooper3@citrix.com"; x-sender="Andrew.Cooper3@citrix.com"; x-conformance=sidf_compatible; x-record-type="v=spf1"; x-record-text="v=spf1 ip4:209.167.231.154 ip4:178.63.86.133 ip4:195.66.111.40/30 ip4:85.115.9.32/28 ip4:199.102.83.4 ip4:192.28.146.160 ip4:192.28.146.107 ip4:216.52.6.88 ip4:216.52.6.188 ip4:162.221.158.21 ip4:162.221.156.83 ip4:168.245.78.127 ~all" Received-SPF: None (esa4.hc3370-68.iphmx.com: no sender authenticity information available from domain of postmaster@mail.citrix.com) identity=helo; client-ip=162.221.158.21; receiver=esa4.hc3370-68.iphmx.com; envelope-from="Andrew.Cooper3@citrix.com"; x-sender="postmaster@mail.citrix.com"; x-conformance=sidf_compatible IronPort-SDR: m48qUiOlZ8P7av1jl4GyVyrWTRdLAoNNIqxVaOgFgEH1sopO6bdzuQcFm7hqeGp+iNtmZ5YFf5 UhDSsGEsjCBzzEVqxPBAi3c38xUkuV4Ibp+85Ia8ERQRgMaFTi3a0YYyld918yysyBXHXYSMVn WbfK/sKAxlZxBH+Lm3Lt0dDnRD61S3XOgkvWNpXL7rUnDiSBaa3jalfceotKG4zcork/sADPbv 221Rv1WqQbp31yeklth0fmMvURrZWSPij/qv0ib8tVbarohggTwnETkhWCEUnx9XmeMOs+c88O ATc= X-SBRS: 2.7 X-MesageID: 12560048 X-Ironport-Server: esa4.hc3370-68.iphmx.com X-Remote-IP: 162.221.158.21 X-Policy: $RELAYED X-IronPort-AV: E=Sophos;i="5.70,403,1574139600"; d="scan'208";a="12560048" From: Andrew Cooper To: Xen-devel Date: Tue, 4 Feb 2020 20:29:38 +0000 Message-ID: <20200204202938.9605-1-andrew.cooper3@citrix.com> X-Mailer: git-send-email 2.11.0 MIME-Version: 1.0 Subject: [Xen-devel] [PATCH] libxc/restore: Fix REC_TYPE_X86_PV_VCPU_XSAVE data auditing (take 2) X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Andrew Cooper , Igor Druzhinin , Wei Liu , Ian Jackson Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" It turns out that a bug (since forever) in Xen causes XSAVE records to have non-architectural behaviour on xsave-capable hardware, when a PV guest has not touched the state. In such a case, the data record returned from Xen is 2*uint64_t, both claiming the (illegitimate) state of %xcr0 and %xcr0_accum being 0. Adjust the bound in handle_x86_pv_vcpu_blob() to cope with this. Fixes: 2a62c22715b "libxc/restore: Fix data auditing in handle_x86_pv_vcpu_blob()" Reported-by: Igor Druzhinin Signed-off-by: Andrew Cooper Acked-by: Wei Liu --- CC: Ian Jackson CC: Wei Liu CC: Igor Druzhinin I'll see about fixing Xen at some other point. A second bug is that we have two copies of part of the vCPU's FPU state. --- tools/libxc/xc_sr_restore_x86_pv.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/libxc/xc_sr_restore_x86_pv.c b/tools/libxc/xc_sr_restore_x86_pv.c index 16e738884e..904ccc462a 100644 --- a/tools/libxc/xc_sr_restore_x86_pv.c +++ b/tools/libxc/xc_sr_restore_x86_pv.c @@ -827,10 +827,10 @@ static int handle_x86_pv_vcpu_blob(struct xc_sr_context *ctx, break; case REC_TYPE_X86_PV_VCPU_XSAVE: - if ( blobsz < 128 ) + if ( blobsz < 16 ) { ERROR("%s record too short: min %zu, got %u", - rec_name, sizeof(*vhdr) + 128, rec->length); + rec_name, sizeof(*vhdr) + 16, rec->length); goto out; } blob = &vcpu->xsave;