From patchwork Wed Sep 16 10:41:10 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 7193991 Return-Path: X-Original-To: patchwork-kvm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 8AA5BBEEC1 for ; Wed, 16 Sep 2015 10:41:36 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 7B54720837 for ; Wed, 16 Sep 2015 10:41:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7A6D620809 for ; Wed, 16 Sep 2015 10:41:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753038AbbIPKlb (ORCPT ); Wed, 16 Sep 2015 06:41:31 -0400 Received: from foss.arm.com ([217.140.101.70]:54879 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751945AbbIPKla (ORCPT ); Wed, 16 Sep 2015 06:41:30 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5A3E556C; Wed, 16 Sep 2015 03:41:46 -0700 (PDT) Received: from approximate.cambridge.arm.com (approximate.cambridge.arm.com [10.1.209.148]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 66C083F57E; Wed, 16 Sep 2015 03:41:29 -0700 (PDT) From: Marc Zyngier To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org Cc: Christoffer Dall , =?UTF-8?q?Alex=20Benn=C3=A9e?= , Peter Maydell Subject: [PATCH] arm64: KVM: Fix user access for debug registers Date: Wed, 16 Sep 2015 11:41:10 +0100 Message-Id: <1442400070-23316-1-git-send-email-marc.zyngier@arm.com> X-Mailer: git-send-email 2.1.4 MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP When setting the debug register from userspace, make sure that copy_from_user() is called with its parameters in the expected order. It otherwise doesn't do what you think. Reported-by: Peter Maydell Cc: Alex Bennée Fixes: 84e690bfbed1 ("KVM: arm64: introduce vcpu->arch.debug_ptr") Signed-off-by: Marc Zyngier Reviewed-by: Christoffer Dall Reviewed-by: Alex Bennée --- arch/arm64/kvm/sys_regs.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index b41607d..1d0463e 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -272,7 +272,7 @@ static int set_bvr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, { __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_bvr[rd->reg]; - if (copy_from_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) + if (copy_from_user(r, uaddr, KVM_REG_SIZE(reg->id)) != 0) return -EFAULT; return 0; } @@ -314,7 +314,7 @@ static int set_bcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, { __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_bcr[rd->reg]; - if (copy_from_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) + if (copy_from_user(r, uaddr, KVM_REG_SIZE(reg->id)) != 0) return -EFAULT; return 0; @@ -358,7 +358,7 @@ static int set_wvr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, { __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_wvr[rd->reg]; - if (copy_from_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) + if (copy_from_user(r, uaddr, KVM_REG_SIZE(reg->id)) != 0) return -EFAULT; return 0; } @@ -400,7 +400,7 @@ static int set_wcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, { __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_wcr[rd->reg]; - if (copy_from_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) + if (copy_from_user(r, uaddr, KVM_REG_SIZE(reg->id)) != 0) return -EFAULT; return 0; }