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 76878C3B18C for ; Thu, 13 Feb 2020 15:56:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 427E6217F4 for ; Thu, 13 Feb 2020 15:56:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581609407; bh=CSrHh6ckbplG7cDGcTH5GkDJu+ynBZmL5i67RFtgq/4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=fc1XaTrK7g8idqppcCwvqQgVhMi1VfvnfVVbezhpIsUMTRwBC22dMuUb3uG5pN79C Xcz8pY/nWcMTzeclHuL/EiCuY0vqstkleDfKPZ7/4J8zPbKF2stGMTJOkTXBVvyUwy 1Rf/x33Ho9ftcLecZcFowT/ufUbGwuLjyRoO2s8c= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387702AbgBMP4i (ORCPT ); Thu, 13 Feb 2020 10:56:38 -0500 Received: from mail.kernel.org ([198.145.29.99]:41104 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728512AbgBMPZ0 (ORCPT ); Thu, 13 Feb 2020 10:25:26 -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 F098324689; Thu, 13 Feb 2020 15:25:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581607526; bh=CSrHh6ckbplG7cDGcTH5GkDJu+ynBZmL5i67RFtgq/4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=2eukpSsNj/ybjLI/HQ725cfK2SULY/DJY/3nceZARMf0b1iOO9gTyPpNw1quXhrkN ISmnJCztfGvPt+2x7CM9AJuG7y0N5xWIfCrZje2VgFz7jfhgap1DSL51W96faAve6U Jv3N4P/ZUoZ3N8BG7Tkefv8IoOHFpeaWrblPLCik= 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 4.14 078/173] KVM: x86: Refactor picdev_write() to prevent Spectre-v1/L1TF attacks Date: Thu, 13 Feb 2020 07:19:41 -0800 Message-Id: <20200213151953.161057552@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: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Marios Pomonis commit 14e32321f3606e4b0970200b6e5e47ee6f1e6410 upstream. 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: 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 Reviewed-by: Jim Mattson Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/i8259.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) --- a/arch/x86/kvm/i8259.c +++ b/arch/x86/kvm/i8259.c @@ -460,10 +460,14 @@ static int picdev_write(struct kvm_pic * 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: