From patchwork Mon Aug 17 15:57:56 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Roger Pau Monne X-Patchwork-Id: 11718747 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 0A7C6109B for ; Mon, 17 Aug 2020 15:59:34 +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 D923D2072E for ; Mon, 17 Aug 2020 15:59:33 +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="Y1btFBef" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D923D2072E Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=citrix.com Authentication-Results: mail.kernel.org; spf=pass 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 4.92) (envelope-from ) id 1k7hXG-00072L-70; Mon, 17 Aug 2020 15:58:58 +0000 Received: from all-amaz-eas1.inumbo.com ([34.197.232.57] helo=us1-amaz-eas2.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1k7hXE-0006wT-Sr for xen-devel@lists.xenproject.org; Mon, 17 Aug 2020 15:58:56 +0000 X-Inumbo-ID: 2ce9f53b-fa70-4091-9fe2-e08bcbb8e0ef Received: from esa4.hc3370-68.iphmx.com (unknown [216.71.155.144]) by us1-amaz-eas2.inumbo.com (Halon) with ESMTPS id 2ce9f53b-fa70-4091-9fe2-e08bcbb8e0ef; Mon, 17 Aug 2020 15:58:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=citrix.com; s=securemail; t=1597679933; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=QNFt2MaUZcrOOAd88SQa0Ik2DvsRYhMp9yfE1IOX5hU=; b=Y1btFBefmPM8R1xh6XGy7YzgfqnRLNmoJQlhrDnXSvUjwcVMkqPPdCQd QpM2V4A8c+jhcxHoXIW96HI7vkK8z4VTq+YliykSk7lvrkk/sx4wd0WJO Ly5f1kwKo6iaW9IgankPKr7P+l4CWPJlokSBvvY8qxxiUnxlVQpjom2aq w=; Authentication-Results: esa4.hc3370-68.iphmx.com; dkim=none (message not signed) header.i=none IronPort-SDR: NU9qgm32sbZAg/M6wZCR814YO56u5+nQkqPxfQY6imYPhVmCJ0901RS9QRLzbmQCFQR3U8r538 zzhZ+JcpAxA5TCUddnOmWSAVeq36BYI5POJWt4HU+DoCXsyEWfcM0JXqOVbP64+ffpvJ9qDCTn PnF+c10//W6bOXIUtKENaPf+SJQJWfCS6R0JDFa7FMGLygthS+gewHlkkDssWmCpQxFg+gfnrq oN95CG2eSDgr4UXyXRvoe1pu4T3oBUEIa+tAYcfoMLZNVXraa1pcnEbOh+YhxA+dK7WaWmXnbB WfY= X-SBRS: 2.7 X-MesageID: 25616946 X-Ironport-Server: esa4.hc3370-68.iphmx.com X-Remote-IP: 162.221.158.21 X-Policy: $RELAYED X-IronPort-AV: E=Sophos;i="5.76,324,1592884800"; d="scan'208";a="25616946" From: Roger Pau Monne To: CC: Roger Pau Monne , Jan Beulich , Andrew Cooper , Wei Liu Subject: [PATCH 7/8] x86/pv: disallow access to unknown MSRs Date: Mon, 17 Aug 2020 17:57:56 +0200 Message-ID: <20200817155757.3372-8-roger.pau@citrix.com> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200817155757.3372-1-roger.pau@citrix.com> References: <20200817155757.3372-1-roger.pau@citrix.com> MIME-Version: 1.0 X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" Change the catch-all behavior for MSR not explicitly handled. Instead of allow full read-access to the MSR space and silently dropping writes return an exception when the MSR is not explicitly handled. Signed-off-by: Roger Pau Monné Acked-by: Andrew Cooper --- xen/arch/x86/pv/emul-priv-op.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) diff --git a/xen/arch/x86/pv/emul-priv-op.c b/xen/arch/x86/pv/emul-priv-op.c index 76c878b677..fcbcf5a6c2 100644 --- a/xen/arch/x86/pv/emul-priv-op.c +++ b/xen/arch/x86/pv/emul-priv-op.c @@ -976,9 +976,10 @@ static int read_msr(unsigned int reg, uint64_t *val, } /* fall through */ default: + gdprintk(XENLOG_WARNING, "RDMSR 0x%08x unimplemented\n", reg); + break; + normal: - /* Everyone can read the MSR space. */ - /* gdprintk(XENLOG_WARNING, "Domain attempted RDMSR %08x\n", reg); */ if ( rdmsr_safe(reg, *val) ) break; return X86EMUL_OKAY; @@ -1143,14 +1144,15 @@ static int write_msr(unsigned int reg, uint64_t val, } /* fall through */ default: - if ( rdmsr_safe(reg, temp) ) - break; + gdprintk(XENLOG_WARNING, + "WRMSR 0x%08x val 0x%016"PRIx64" unimplemented\n", + reg, val); + break; - if ( val != temp ) invalid: - gdprintk(XENLOG_WARNING, - "Domain attempted WRMSR %08x from 0x%016"PRIx64" to 0x%016"PRIx64"\n", - reg, temp, val); + gdprintk(XENLOG_WARNING, + "Domain attempted WRMSR %08x from 0x%016"PRIx64" to 0x%016"PRIx64"\n", + reg, temp, val); return X86EMUL_OKAY; }