From patchwork Wed May 12 14:42:42 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 438053 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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT 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 6BF6DC2B9F2 for ; Wed, 12 May 2021 16:37:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 33E8561107 for ; Wed, 12 May 2021 16:37:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235792AbhELQhW (ORCPT ); Wed, 12 May 2021 12:37:22 -0400 Received: from mail.kernel.org ([198.145.29.99]:42394 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241763AbhELQ2A (ORCPT ); Wed, 12 May 2021 12:28:00 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 5C47061628; Wed, 12 May 2021 15:55:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1620834956; bh=/wvoLUyYA1UsjMAd2kS2Adrl6OoTyo2MbKp7UH4xLjY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NquT0eZ71NQIheXbaKb9NsJrmDG+VRw7ndIMzMdSbvP/h5hUF90ypRJ1KgPg6XOah YFQIfTJ3u5L5sPmj6HS9zamRnoqXgcBmctgon+BqQW4s0ovZkUDNhip4ja1UGHCYY2 XffKla2vOephF4juO2AM5sJHCpAvHe+Kog/Lhomg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Brijesh Singh , Tom Lendacky , Sean Christopherson , Paolo Bonzini Subject: [PATCH 5.12 116/677] KVM: SVM: Do not allow SEV/SEV-ES initialization after vCPUs are created Date: Wed, 12 May 2021 16:42:42 +0200 Message-Id: <20210512144841.066163943@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210512144837.204217980@linuxfoundation.org> References: <20210512144837.204217980@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Sean Christopherson commit 8727906fde6ea665b52e68ddc58833772537f40a upstream. Reject KVM_SEV_INIT and KVM_SEV_ES_INIT if they are attempted after one or more vCPUs have been created. KVM assumes a VM is tagged SEV/SEV-ES prior to vCPU creation, e.g. init_vmcb() needs to mark the VMCB as SEV enabled, and svm_create_vcpu() needs to allocate the VMSA. At best, creating vCPUs before SEV/SEV-ES init will lead to unexpected errors and/or behavior, and at worst it will crash the host, e.g. sev_launch_update_vmsa() will dereference a null svm->vmsa pointer. Fixes: 1654efcbc431 ("KVM: SVM: Add KVM_SEV_INIT command") Fixes: ad73109ae7ec ("KVM: SVM: Provide support to launch and run an SEV-ES guest") Cc: stable@vger.kernel.org Cc: Brijesh Singh Cc: Tom Lendacky Signed-off-by: Sean Christopherson Message-Id: <20210331031936.2495277-4-seanjc@google.com> Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/svm/sev.c | 3 +++ 1 file changed, 3 insertions(+) --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -182,6 +182,9 @@ static int sev_guest_init(struct kvm *kv bool es_active = argp->id == KVM_SEV_ES_INIT; int asid, ret; + if (kvm->created_vcpus) + return -EINVAL; + ret = -EBUSY; if (unlikely(sev->active)) return ret;