From patchwork Thu Oct 4 11:56:05 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paul Mackerras X-Patchwork-Id: 10626013 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4FCBD17E0 for ; Thu, 4 Oct 2018 11:56:48 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3F00D28E47 for ; Thu, 4 Oct 2018 11:56:48 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3269C28E79; Thu, 4 Oct 2018 11:56:48 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id BA80528E47 for ; Thu, 4 Oct 2018 11:56:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727629AbeJDSte (ORCPT ); Thu, 4 Oct 2018 14:49:34 -0400 Received: from ozlabs.org ([203.11.71.1]:45859 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727627AbeJDStd (ORCPT ); Thu, 4 Oct 2018 14:49:33 -0400 Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPSA id 42Qrvm0bVfzB4NR; Thu, 4 Oct 2018 21:56:36 +1000 (AEST) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=ozlabs.org DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ozlabs.org; s=201707; t=1538654196; bh=reJiOr/rOtA+EbVRyPzCx6KaCXK7LKR+tqEqffS0WKY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=vV5EhcNjklMH2+cpJ9RT51q5uh1/ULCsh8ncJvJ0IHbLWMdGK4IoPtqU6OpVsfJZb 0kbrzVMz7YhQDv2hfFkqiQ5mOzUBSyjjTXZcJHTGVyIGEjwdMRptQmys8tZMXtx/X/ hqe0saeFVLZPD1YdViiYlaXy2FKIUmgbbnu3/ECbzSK1tMGAAlA5CwES8kYjKGJtVy lJBcoh4iF7/0rbrZGlhR4DhF9EvisamcWNsdD+62Ilb+TSXfOuAAAKMBTASPwVeszA jZpjJ5SBA7xYorWLYt6noaU+67WIBmyt+rH0Y4gkVJnH7VG0DOQItS74tSbO1bZTB3 53huiuzNx6/mw== From: Paul Mackerras To: kvm@vger.kernel.org, kvm-ppc@vger.kernel.org Cc: linuxppc-dev@ozlabs.org, David Gibson Subject: [PATCH v4 28/32] KVM: PPC: Book3S HV: Sanitise hv_regs on nested guest entry Date: Thu, 4 Oct 2018 21:56:05 +1000 Message-Id: <1538654169-15602-29-git-send-email-paulus@ozlabs.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1538654169-15602-1-git-send-email-paulus@ozlabs.org> References: <1538654169-15602-1-git-send-email-paulus@ozlabs.org> Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Suraj Jitindar Singh restore_hv_regs() is used to copy the hv_regs L1 wants to set to run the nested (L2) guest into the vcpu structure. We need to sanitise these values to ensure we don't let the L1 guest hypervisor do things we don't want it to. We don't let data address watchpoints or completed instruction address breakpoints be set to match in hypervisor state. We also don't let L1 enable features in the hypervisor facility status and control register (HFSCR) for L2 which we have disabled for L1. That is L2 will get the subset of features which the L0 hypervisor has enabled for L1 and the features L1 wants to enable for L2. This could mean we give L1 a hypervisor facility unavailable interrupt for a facility it thinks it has enabled, however it shouldn't have enabled a facility it itself doesn't have for the L2 guest. We sanitise the registers when copying in the L2 hv_regs. We don't need to sanitise when copying back the L1 hv_regs since these shouldn't be able to contain invalid values as they're just what was copied out. Reviewed-by: David Gibson Signed-off-by: Suraj Jitindar Singh Signed-off-by: Paul Mackerras --- arch/powerpc/include/asm/reg.h | 1 + arch/powerpc/kvm/book3s_hv_nested.c | 17 +++++++++++++++++ 2 files changed, 18 insertions(+) diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h index 6fda746..c9069897 100644 --- a/arch/powerpc/include/asm/reg.h +++ b/arch/powerpc/include/asm/reg.h @@ -415,6 +415,7 @@ #define HFSCR_DSCR __MASK(FSCR_DSCR_LG) #define HFSCR_VECVSX __MASK(FSCR_VECVSX_LG) #define HFSCR_FP __MASK(FSCR_FP_LG) +#define HFSCR_INTR_CAUSE (ASM_CONST(0xFF) << 56) /* interrupt cause */ #define SPRN_TAR 0x32f /* Target Address Register */ #define SPRN_LPCR 0x13E /* LPAR Control Register */ #define LPCR_VPM0 ASM_CONST(0x8000000000000000) diff --git a/arch/powerpc/kvm/book3s_hv_nested.c b/arch/powerpc/kvm/book3s_hv_nested.c index 1a8c40d..f54f779 100644 --- a/arch/powerpc/kvm/book3s_hv_nested.c +++ b/arch/powerpc/kvm/book3s_hv_nested.c @@ -85,6 +85,22 @@ static void save_hv_return_state(struct kvm_vcpu *vcpu, int trap, } } +static void sanitise_hv_regs(struct kvm_vcpu *vcpu, struct hv_guest_state *hr) +{ + /* + * Don't let L1 enable features for L2 which we've disabled for L1, + * but preserve the interrupt cause field. + */ + hr->hfscr &= (HFSCR_INTR_CAUSE | vcpu->arch.hfscr); + + /* Don't let data address watchpoint match in hypervisor state */ + hr->dawrx0 &= ~DAWRX_HYP; + + /* Don't let completed instruction address breakpt match in HV state */ + if ((hr->ciabr & CIABR_PRIV) == CIABR_PRIV_HYPER) + hr->ciabr &= ~CIABR_PRIV; +} + static void restore_hv_regs(struct kvm_vcpu *vcpu, struct hv_guest_state *hr) { struct kvmppc_vcore *vc = vcpu->arch.vcore; @@ -197,6 +213,7 @@ long kvmhv_enter_nested_guest(struct kvm_vcpu *vcpu) mask = LPCR_DPFD | LPCR_ILE | LPCR_TC | LPCR_AIL | LPCR_LD | LPCR_LPES | LPCR_MER; lpcr = (vc->lpcr & ~mask) | (l2_hv.lpcr & mask); + sanitise_hv_regs(vcpu, &l2_hv); restore_hv_regs(vcpu, &l2_hv); vcpu->arch.ret = RESUME_GUEST;