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=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, 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,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 8F882C433E2 for ; Wed, 31 Mar 2021 03:20:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 67611619D9 for ; Wed, 31 Mar 2021 03:20:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233628AbhCaDUX (ORCPT ); Tue, 30 Mar 2021 23:20:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42366 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233486AbhCaDTu (ORCPT ); Tue, 30 Mar 2021 23:19:50 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 16F5DC061574 for ; Tue, 30 Mar 2021 20:19:50 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id c17so822614ybs.0 for ; Tue, 30 Mar 2021 20:19:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=reply-to:date:in-reply-to:message-id:mime-version:references :subject:from:to:cc; bh=3Xa1OKEIcZ5edRwAMZLibB+Ad1pcD0ADTTrJiSO76FU=; b=U0dDAMw5AWHxlOqCtiXJpoymuGVxzLFXL1A4mlfI9uLaMbLLGk45tLAgKX1qjOccmR cTevpLRzVJqNmfwPQFzh9m2DRDgvyV3sxKLBL7DGw0tBxNZU1FmmCrBGRaxm+XeF9GhC Hwe2L+EpDVfyH3o2QCwSMd12qVhUUklccyj9paEDibFrU+0bp42pkhunV4PyqQJqGCCY lDKuGej38L4ReQUgV+4kMcPpL8C5+/EMh7xgg98CsQBhDcKL9WWhhvb8H9cbfufK/VfC IkdR/BrdtTxnTKbkHjjcbWTKDtDWNRmft5OnlBUgBnLeNFPVsA6t6+1wUWKw4E/Jv7Wj rXUQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:reply-to:date:in-reply-to:message-id :mime-version:references:subject:from:to:cc; bh=3Xa1OKEIcZ5edRwAMZLibB+Ad1pcD0ADTTrJiSO76FU=; b=l0rQRiRmQ96OaBlqGggh4Ig2ldjRQ28zA2R9d57XIL5NnfcA6of+Za5FJ975LuXWqi fU7X8y22Y7wssGQMFFTTSR5X5BPyAX6bDBylWMdLydnEKB+PNLBzg3C51w4UBgGPAe5K NitX142pkXXMIe3s4nGqNip/bpUzn1QpmxGp0r/Mu6N573xh3jht7L2Vjd++oeUiErWI eOc6MwRaFAe1mMmIrz+h+QdN/zW3tL6rr0p4N5EN6zSXvVvsiL7F6YvVSegx5t6+PVpX pF2+ykLk8rfmvCTuBS3Cfc/G1/7MIQvMEdXw1yoS/EQ6ae2u4n8O+OiJKEex4Mz0A6zB gUUw== X-Gm-Message-State: AOAM530nQGz86pgSEdgXMrA3Izm75mUJbLVTpch2p2NYyYjrkETVcAZM s66X6zKC3S6HEYOhnu8HgZ5wUdOuFGQ= X-Google-Smtp-Source: ABdhPJzBx7uD+67poCDf2QYRxAznyzYMGF0Hynxyll63eq1q/oZtnzx23zwvh/FRi1trMJENU/uX+ZtWzOA= X-Received: from seanjc798194.pdx.corp.google.com ([2620:15c:f:10:6c6b:5d63:9b3b:4a77]) (user=seanjc job=sendgmr) by 2002:a25:268e:: with SMTP id m136mr1876235ybm.220.1617160789338; Tue, 30 Mar 2021 20:19:49 -0700 (PDT) Reply-To: Sean Christopherson Date: Tue, 30 Mar 2021 20:19:36 -0700 In-Reply-To: <20210331031936.2495277-1-seanjc@google.com> Message-Id: <20210331031936.2495277-4-seanjc@google.com> Mime-Version: 1.0 References: <20210331031936.2495277-1-seanjc@google.com> X-Mailer: git-send-email 2.31.0.291.g576ba9dcdaf-goog Subject: [PATCH 3/3] KVM: SVM: Do not allow SEV/SEV-ES initialization after vCPUs are created From: Sean Christopherson To: Paolo Bonzini Cc: Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Brijesh Singh , Tom Lendacky Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 --- arch/x86/kvm/svm/sev.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index 97d42a007b86..824bc7d22e77 100644 --- 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 *kvm, struct kvm_sev_cmd *argp) 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; -- 2.31.0.291.g576ba9dcdaf-goog