From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753125AbdCMJAw (ORCPT ); Mon, 13 Mar 2017 05:00:52 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:40478 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752623AbdCMIpf (ORCPT ); Mon, 13 Mar 2017 04:45:35 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Janosch Frank , Martin Schwidefsky , Cornelia Huck , Christian Borntraeger Subject: [PATCH 4.10 03/75] KVM: s390: Disable dirty log retrieval for UCONTROL guests Date: Mon, 13 Mar 2017 16:43:12 +0800 Message-Id: <20170313083411.595859509@linuxfoundation.org> X-Mailer: git-send-email 2.12.0 In-Reply-To: <20170313083411.408297387@linuxfoundation.org> References: <20170313083411.408297387@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Janosch Frank commit e1e8a9624f7ba8ead4f056ff558ed070e86fa747 upstream. User controlled KVM guests do not support the dirty log, as they have no single gmap that we can check for changes. As they have no single gmap, kvm->arch.gmap is NULL and all further referencing to it for dirty checking will result in a NULL dereference. Let's return -EINVAL if a caller tries to sync dirty logs for a UCONTROL guest. Fixes: 15f36eb ("KVM: s390: Add proper dirty bitmap support to S390 kvm.") Signed-off-by: Janosch Frank Reported-by: Martin Schwidefsky Reviewed-by: Cornelia Huck Signed-off-by: Christian Borntraeger Signed-off-by: Greg Kroah-Hartman --- arch/s390/kvm/kvm-s390.c | 3 +++ 1 file changed, 3 insertions(+) --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -442,6 +442,9 @@ int kvm_vm_ioctl_get_dirty_log(struct kv struct kvm_memory_slot *memslot; int is_dirty = 0; + if (kvm_is_ucontrol(kvm)) + return -EINVAL; + mutex_lock(&kvm->slots_lock); r = -EINVAL;