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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS 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 32755C433F4 for ; Mon, 27 Aug 2018 16:49:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EC61D208B9 for ; Mon, 27 Aug 2018 16:49:09 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EC61D208B9 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727395AbeH0Uga (ORCPT ); Mon, 27 Aug 2018 16:36:30 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:33528 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726994AbeH0Ug3 (ORCPT ); Mon, 27 Aug 2018 16:36:29 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 3438640201CB; Mon, 27 Aug 2018 16:49:07 +0000 (UTC) Received: from vitty.brq.redhat.com (ovpn-204-86.brq.redhat.com [10.40.204.86]) by smtp.corp.redhat.com (Postfix) with ESMTP id EFF5F2166B41; Mon, 27 Aug 2018 16:49:03 +0000 (UTC) From: Vitaly Kuznetsov To: kvm@vger.kernel.org Cc: Paolo Bonzini , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , Roman Kagan , "K. Y. Srinivasan" , Haiyang Zhang , Stephen Hemminger , "Michael Kelley (EOSG)" , Mohammed Gamal , Cathy Avery , Wanpeng Li , linux-kernel@vger.kernel.org Subject: [PATCH v5 1/5] KVM: x86: hyperv: enforce vp_index < KVM_MAX_VCPUS Date: Mon, 27 Aug 2018 18:48:54 +0200 Message-Id: <20180827164858.12496-2-vkuznets@redhat.com> In-Reply-To: <20180827164858.12496-1-vkuznets@redhat.com> References: <20180827164858.12496-1-vkuznets@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.6 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.6]); Mon, 27 Aug 2018 16:49:07 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.6]); Mon, 27 Aug 2018 16:49:07 +0000 (UTC) for IP:'10.11.54.6' DOMAIN:'int-mx06.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'vkuznets@redhat.com' RCPT:'' Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hyper-V TLFS (5.0b) states: > Virtual processors are identified by using an index (VP index). The > maximum number of virtual processors per partition supported by the > current implementation of the hypervisor can be obtained through CPUID > leaf 0x40000005. A virtual processor index must be less than the > maximum number of virtual processors per partition. Forbid userspace to set VP_INDEX above KVM_MAX_VCPUS. get_vcpu_by_vpidx() can now be optimized to bail early when supplied vpidx is >= KVM_MAX_VCPUS. Signed-off-by: Vitaly Kuznetsov Reviewed-by: Roman Kagan --- arch/x86/kvm/hyperv.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c index 01d209ab5481..0cd597b0f754 100644 --- a/arch/x86/kvm/hyperv.c +++ b/arch/x86/kvm/hyperv.c @@ -132,8 +132,10 @@ static struct kvm_vcpu *get_vcpu_by_vpidx(struct kvm *kvm, u32 vpidx) struct kvm_vcpu *vcpu = NULL; int i; - if (vpidx < KVM_MAX_VCPUS) - vcpu = kvm_get_vcpu(kvm, vpidx); + if (vpidx >= KVM_MAX_VCPUS) + return NULL; + + vcpu = kvm_get_vcpu(kvm, vpidx); if (vcpu && vcpu_to_hv_vcpu(vcpu)->vp_index == vpidx) return vcpu; kvm_for_each_vcpu(i, vcpu, kvm) @@ -1044,7 +1046,7 @@ static int kvm_hv_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data, bool host) switch (msr) { case HV_X64_MSR_VP_INDEX: - if (!host) + if (!host || (u32)data >= KVM_MAX_VCPUS) return 1; hv->vp_index = (u32)data; break; -- 2.14.4