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=ham 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 7050EC43603 for ; Wed, 11 Dec 2019 20:48:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 467F0222C4 for ; Wed, 11 Dec 2019 20:48:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="Bpdltt77" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727213AbfLKUsh (ORCPT ); Wed, 11 Dec 2019 15:48:37 -0500 Received: from mail-pf1-f201.google.com ([209.85.210.201]:45722 "EHLO mail-pf1-f201.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726623AbfLKUse (ORCPT ); Wed, 11 Dec 2019 15:48:34 -0500 Received: by mail-pf1-f201.google.com with SMTP id x21so2833696pfp.12 for ; Wed, 11 Dec 2019 12:48:34 -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=C+6y73EXexRd0hR33vMuaMfO+5uThh3OpWASDclUdXg=; b=Bpdltt77InkOqMirGb9hF5cYmu5WGJuJ0I+s7SKo/MEfJ+hx2Gwwknfp4zMiBTWF5v KbKS2NW6PiYL2+p90yprg30UiDj51uWLgi/dpDBYgFFz5+ZoopDQK7yjbD+swPEhw6uO mDkPxhUFVZdctOJIiSjQ+8YIAO7teNe2UyR6/0grkYqGZuc5hV5FNOPVqul9pWo3ZQ7y A1TWZl83lLWARjYcmw8CkdJ98Sk7sznx06fGkfdV1jkSFW+sJ6KCnn6lE72jprhRTgPA 11t8BFJCfr1kfDEPVgGbHCWebxeb/vfn5S5AKLqH4F6RY5OumAIpOfzrueEQ7Genu8jV QTMw== 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=C+6y73EXexRd0hR33vMuaMfO+5uThh3OpWASDclUdXg=; b=hAHf3aEWBphRb1lFP/JgyaZRTL+2+SMGsu0A2R1ELw2pjjx3AnFxVyxvUThD+w81/X 8U7AWwgHXYJYznvyepCGW7P1lTyo1hEsQZOm7r6AAI/YvpmjRUBNvD4VervVSrVu3lH0 qN1dYIAwRepryIHyn6q77xAG340Tsynsra9QEsd3seYxOyBrEJN8vfg+KlxBjEqcC8rl 3++Z46pW/gQbKPrNagnBA8u4meTxh9lcjAsGeAfVeJ2Fa+jpkck6NPXoyeAAuhRpdr25 gjD9G7K21OC3w88Z7hvMMAYA2m955eSKbknVnwb5w7SSsad2Hxu4uVde9K+sm7AJwt+C gXiQ== X-Gm-Message-State: APjAAAVY40WKGYN3i8tsh0AtejjJ1ItMl6ooGuXuXeHI5rlILR6tvHtr ZEktrYZdWMExlTh1FCaim+SP8hTmuIv6 X-Google-Smtp-Source: APXvYqxauN2Xtwim1usUncxq4tvoh++Me89sTxe8ma6YZe7/GQCKgFE7FrAPcyLob9kJpl5tHySpflrnNfOA X-Received: by 2002:a63:e14b:: with SMTP id h11mr6137550pgk.297.1576097314200; Wed, 11 Dec 2019 12:48:34 -0800 (PST) Date: Wed, 11 Dec 2019 12:47:43 -0800 In-Reply-To: <20191211204753.242298-1-pomonis@google.com> Message-Id: <20191211204753.242298-4-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 03/13] KVM: x86: Refactor picdev_write() to prevent 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: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This fixes a Spectre-v1/L1TF vulnerability in picdev_write(). It replaces index computations based on the (attacked-controlled) port number with constants through a minor refactoring. Fixes: commit 85f455f7ddbe ("KVM: Add support for in-kernel PIC emulation") Signed-off-by: Nick Finco Signed-off-by: Marios Pomonis Reviewed-by: Andrew Honig Cc: stable@vger.kernel.org --- arch/x86/kvm/i8259.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c index 8b38bb4868a6..629a09ca9860 100644 --- a/arch/x86/kvm/i8259.c +++ b/arch/x86/kvm/i8259.c @@ -460,10 +460,14 @@ static int picdev_write(struct kvm_pic *s, switch (addr) { case 0x20: case 0x21: + pic_lock(s); + pic_ioport_write(&s->pics[0], addr, data); + pic_unlock(s); + break; case 0xa0: case 0xa1: pic_lock(s); - pic_ioport_write(&s->pics[addr >> 7], addr, data); + pic_ioport_write(&s->pics[1], addr, data); pic_unlock(s); break; case 0x4d0: -- 2.24.0.525.g8f36a354ae-goog