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 X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7176FC3B189 for ; Thu, 13 Feb 2020 15:57:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 39ED02073C for ; Thu, 13 Feb 2020 15:57:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581609437; bh=m6L8pam+h6zNTKCrrIJgMWsEWjH208nmDDvKR29STTM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=jE0cs/vK/qVbsG2IjJlfRAWkfONqBOP8mjwsY3lFDr/PLTwPZJk2X6ewSzlC1G6p5 7qQFoFPLec47UyuPQxMWdlwMLGMw/EnFLQJZfI7X5rX0w/SsMBh2IYsHQlDiqXxHVq HmCah87/ndarBhtV+Vf/iYyYrgRwev4LtmyolyPc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728972AbgBMPZV (ORCPT ); Thu, 13 Feb 2020 10:25:21 -0500 Received: from mail.kernel.org ([198.145.29.99]:40532 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728968AbgBMPZV (ORCPT ); Thu, 13 Feb 2020 10:25:21 -0500 Received: from localhost (unknown [104.132.1.104]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 386A420848; Thu, 13 Feb 2020 15:25:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581607520; bh=m6L8pam+h6zNTKCrrIJgMWsEWjH208nmDDvKR29STTM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PDZsqbBjfF1bAZCqd6v7gWKyRY9SyEoteMuHaIB2wDAjZI/D/ROnOrnYNQShjdstn D2AyT6xlx8uLdlCnkDaojp5jyA7CYdGtTmMgMwc2kwsQUFpiI9SEdoNOwpZ4s3Wlgy JQTy0nMvKdU+ZDThB3PspNj+VRvx3OwQEKwLYvk4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Nick Finco , Marios Pomonis , Andrew Honig , Jim Mattson , Paolo Bonzini Subject: [PATCH 4.14 086/173] KVM: x86: Protect MSR-based index computations from Spectre-v1/L1TF attacks in x86.c Date: Thu, 13 Feb 2020 07:19:49 -0800 Message-Id: <20200213151954.912757003@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200213151931.677980430@linuxfoundation.org> References: <20200213151931.677980430@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Marios Pomonis commit 6ec4c5eee1750d5d17951c4e1960d953376a0dda upstream. This fixes a Spectre-v1/L1TF vulnerability in set_msr_mce() and get_msr_mce(). Both functions contain index computations based on the (attacker-controlled) MSR number. Fixes: 890ca9aefa78 ("KVM: Add MCE support") Signed-off-by: Nick Finco Signed-off-by: Marios Pomonis Reviewed-by: Andrew Honig Cc: stable@vger.kernel.org Reviewed-by: Jim Mattson Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/x86.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2165,7 +2165,10 @@ static int set_msr_mce(struct kvm_vcpu * default: if (msr >= MSR_IA32_MC0_CTL && msr < MSR_IA32_MCx_CTL(bank_num)) { - u32 offset = msr - MSR_IA32_MC0_CTL; + u32 offset = array_index_nospec( + msr - MSR_IA32_MC0_CTL, + MSR_IA32_MCx_CTL(bank_num) - MSR_IA32_MC0_CTL); + /* only 0 or all 1s can be written to IA32_MCi_CTL * some Linux kernels though clear bit 10 in bank 4 to * workaround a BIOS/GART TBL issue on AMD K8s, ignore @@ -2549,7 +2552,10 @@ static int get_msr_mce(struct kvm_vcpu * default: if (msr >= MSR_IA32_MC0_CTL && msr < MSR_IA32_MCx_CTL(bank_num)) { - u32 offset = msr - MSR_IA32_MC0_CTL; + u32 offset = array_index_nospec( + msr - MSR_IA32_MC0_CTL, + MSR_IA32_MCx_CTL(bank_num) - MSR_IA32_MC0_CTL); + data = vcpu->arch.mce_banks[offset]; break; }