From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-1427278-1518185000-2-9745878783143423814 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.001, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES endafr, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='US', FromHeader='org', MailFrom='org' X-Spam-charsets: plain='UTF-8' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1518184999; b=Nw4vXd+DfMWRT4EyNTbQ8RWDy/yLrn/EsWLaNgpg68ZTgRt hZtvH8iLXCxnDQTeFXIUEciTta/AasRYsWH6poDsEKsMhrRCQotBhrn0xucUhPXb 8EqiSfBH8HvNSS5l4+kTHsM/BmUZlWV8T/8VGQmWbrstyIsxPSgZjGD9lgRoUKfw 0+9aleEKvFmIDznTLmPnbWkNw2CNeHr7+lTKK0KVJQUpdpB0g8w5lmAQCGZi13fS 0oVM5y+S4u+6PKzXu2f1uZa1B0NRsNJ0hJjXBEVsGobZXYOgGzE6OoUkVwSNkQr2 +xH0ImRxblvxNhmHfYzT3R1ObP+ivzcQIT9C3eg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-type:sender :list-id; s=arctest; t=1518184999; bh=+hOnHHypFOF+/U3VviiSNtRQqa ZG/gvQttODkbHZnzo=; b=VaC7WYBeMVJB2sa4q54yNFYPS3bp6tf7MHGtXg4755 wxZf4FkyqSApTzn/WSZ4kVdF29ZkeVwSmuL8XPou7xzKLswlRQxtHqsNSw9B9MC8 0xp4/GCPi9jTSLvRAZBIczMtmUJ+FMD8QWYrzGtewxHzp9h7evmWRdbxXq/a4l5+ Y8Ay0HslhgaJwlnXpxCeCB5s4oCyVF1JaoHczQokMcdA44x2E+PiGwoX0SsPQ9/n viUDCgeAO3JjKtvv3hC3klneqV6pJHjlr5nDvc7bl2/qrV7Tfi7KTatmYc0WXNc/ wyPpLvLCan9oLjPi0XY0Tr4+/U1KvIvV97g9S6Ek8jNA== ARC-Authentication-Results: i=1; mx3.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes Authentication-Results: mx3.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=linuxfoundation.org; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=linuxfoundation.org header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753399AbeBIODP (ORCPT ); Fri, 9 Feb 2018 09:03:15 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:50864 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753277AbeBINni (ORCPT ); Fri, 9 Feb 2018 08:43:38 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dan Williams , Thomas Gleixner , Paolo Bonzini , Andrew Honig , kvm@vger.kernel.org, Jim Mattson , David Woodhouse Subject: [PATCH 4.9 71/92] x86/kvm: Update spectre-v1 mitigation Date: Fri, 9 Feb 2018 14:39:40 +0100 Message-Id: <20180209133936.369984467@linuxfoundation.org> X-Mailer: git-send-email 2.16.1 In-Reply-To: <20180209133931.211869118@linuxfoundation.org> References: <20180209133931.211869118@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dan Williams (cherry picked from commit 085331dfc6bbe3501fb936e657331ca943827600) Commit 75f139aaf896 "KVM: x86: Add memory barrier on vmcs field lookup" added a raw 'asm("lfence");' to prevent a bounds check bypass of 'vmcs_field_to_offset_table'. The lfence can be avoided in this path by using the array_index_nospec() helper designed for these types of fixes. Signed-off-by: Dan Williams Signed-off-by: Thomas Gleixner Acked-by: Paolo Bonzini Cc: Andrew Honig Cc: kvm@vger.kernel.org Cc: Jim Mattson Link: https://lkml.kernel.org/r/151744959670.6342.3001723920950249067.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: David Woodhouse Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/vmx.c | 20 +++++++++----------- 1 file changed, 9 insertions(+), 11 deletions(-) --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -33,6 +33,7 @@ #include #include #include +#include #include "kvm_cache_regs.h" #include "x86.h" @@ -856,21 +857,18 @@ static const unsigned short vmcs_field_t static inline short vmcs_field_to_offset(unsigned long field) { - BUILD_BUG_ON(ARRAY_SIZE(vmcs_field_to_offset_table) > SHRT_MAX); + const size_t size = ARRAY_SIZE(vmcs_field_to_offset_table); + unsigned short offset; - if (field >= ARRAY_SIZE(vmcs_field_to_offset_table)) + BUILD_BUG_ON(size > SHRT_MAX); + if (field >= size) return -ENOENT; - /* - * FIXME: Mitigation for CVE-2017-5753. To be replaced with a - * generic mechanism. - */ - asm("lfence"); - - if (vmcs_field_to_offset_table[field] == 0) + field = array_index_nospec(field, size); + offset = vmcs_field_to_offset_table[field]; + if (offset == 0) return -ENOENT; - - return vmcs_field_to_offset_table[field]; + return offset; } static inline struct vmcs12 *get_vmcs12(struct kvm_vcpu *vcpu)