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=-17.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT, USER_IN_DEF_DKIM_WL 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 60395C2D0C7 for ; Wed, 11 Dec 2019 20:49:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3075122B48 for ; Wed, 11 Dec 2019 20:49:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="I8V2k3Of" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727302AbfLKUs4 (ORCPT ); Wed, 11 Dec 2019 15:48:56 -0500 Received: from mail-pj1-f73.google.com ([209.85.216.73]:43275 "EHLO mail-pj1-f73.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727045AbfLKUsz (ORCPT ); Wed, 11 Dec 2019 15:48:55 -0500 Received: by mail-pj1-f73.google.com with SMTP id b23so12148619pjz.10 for ; Wed, 11 Dec 2019 12:48:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=0uBm59z2CSkxE1Lwa309Nz0ygPbdvHmq/YUupdQxc7E=; b=I8V2k3Of6lRv1EDUC410FpR8FtBNQM0aht20sKEmAa2g/XoHx4ga+H6HGWK3VmCuRc wTNP5z9oSZKoLgQaiyZRfW3xul3WBjmcGmueZhYjDD73dzB9Pk28xF1dD4sse2hL8zCs jxasrPodRUF5TKbLIqwZEHjdr4+h3zVlhnWMAH3YR8JtbbJmHg/3dkQercCnt+w81iog QF9DyU5dmZwGDqQjdV8hbmxVUMt0l9lKPb2ajtxp0Of4aWkLYwN04vwYz55EgnrVXlpz J2cnKpCAoxhwh6R+UYYFI9d/vgFOs6CdW/2EtwTnyudLXsAeiI9rXMNbv63SXKTHu2dc 9xWw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=0uBm59z2CSkxE1Lwa309Nz0ygPbdvHmq/YUupdQxc7E=; b=etDpfHWVv6t80KCj/ue4EU/7CxZzwC/McHNicJt5MS3S0cYE+t2pR+NVcr+ftJ+r2k yaYq6nXZA1b98Sq3QYs9SKv5+CKyW5RCeh/3e+cd/TRpyrpCHxeBEl/7FnJsOszNNuYw SAEdoZbpfblDmd7X6pZaLR5sMMBSOkuGIfXyRQTiE1VlSUYhMjtQLy0O3/rwT2MjqmOV puyFDIuzF2RP9+n2Rmizk1UbCkA1lzdzgYmAVKXip7j3O34bxjYPOwpv63I6eYJ6tJ+4 D8mlKbVz2cLwEMD0ZRCvoRdNBJjpJGZLqYxtoLBPn7iziV2NCIDSCNB8BNEzQ/T8SzKL RPvw== X-Gm-Message-State: APjAAAV454/cmbJBp0EpzqpV09HpXYfsyvGRNev8UW/yh1CpACb309Cm nEeKY8EC6PnC/hfZoazCYnv3YWu+nQV8 X-Google-Smtp-Source: APXvYqzpV4iFVXiUK5BQScN74ZwB27juWvlBDSrPZNfl+y/rATB6M5QAfuVVUKOtVW9B7wan1hPJvtR1w6Bp X-Received: by 2002:a63:5525:: with SMTP id j37mr6269827pgb.180.1576097334639; Wed, 11 Dec 2019 12:48:54 -0800 (PST) Date: Wed, 11 Dec 2019 12:47:47 -0800 In-Reply-To: <20191211204753.242298-1-pomonis@google.com> Message-Id: <20191211204753.242298-8-pomonis@google.com> Mime-Version: 1.0 References: <20191211204753.242298-1-pomonis@google.com> X-Mailer: git-send-email 2.24.0.525.g8f36a354ae-goog Subject: [PATCH v2 07/13] KVM: x86: Protect MSR-based index computations in fixed_msr_to_seg_unit() from Spectre-v1/L1TF attacks From: Marios Pomonis To: Paolo Bonzini , rkrcmar@redhat.com, Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel Cc: Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , x86@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Nick Finco , Andrew Honig , Marios Pomonis , stable@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org This fixes a Spectre-v1/L1TF vulnerability in fixed_msr_to_seg_unit(). This function contains index computations based on the (attacker-controlled) MSR number. Fixes: commit de9aef5e1ad6 ("KVM: MTRR: introduce fixed_mtrr_segment table") Signed-off-by: Nick Finco Signed-off-by: Marios Pomonis Reviewed-by: Andrew Honig Cc: stable@vger.kernel.org --- arch/x86/kvm/mtrr.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/mtrr.c b/arch/x86/kvm/mtrr.c index 25ce3edd1872..7f0059aa30e1 100644 --- a/arch/x86/kvm/mtrr.c +++ b/arch/x86/kvm/mtrr.c @@ -192,11 +192,15 @@ static bool fixed_msr_to_seg_unit(u32 msr, int *seg, int *unit) break; case MSR_MTRRfix16K_80000 ... MSR_MTRRfix16K_A0000: *seg = 1; - *unit = msr - MSR_MTRRfix16K_80000; + *unit = array_index_nospec( + msr - MSR_MTRRfix16K_80000, + MSR_MTRRfix16K_A0000 - MSR_MTRRfix16K_80000 + 1); break; case MSR_MTRRfix4K_C0000 ... MSR_MTRRfix4K_F8000: *seg = 2; - *unit = msr - MSR_MTRRfix4K_C0000; + *unit = array_index_nospec( + msr - MSR_MTRRfix4K_C0000, + MSR_MTRRfix4K_F8000 - MSR_MTRRfix4K_C0000 + 1); break; default: return false; -- 2.24.0.525.g8f36a354ae-goog