From ee08ab77de75bcb1070aaf6141801808f802b554 Mon Sep 17 00:00:00 2001
From: Alex Williamson <alex.williamson@redhat.com>
Date: Thu, 5 Jan 2012 05:56:56 +0100
Subject: [PATCH 1/2] KVM: Remove ability to assign a device without iommu
 support

RH-Author: Alex Williamson <alex.williamson@redhat.com>
Message-id: <20120105055656.3950.64177.stgit@virtlab9.virt.bos.redhat.com>
Patchwork-id: 36236
O-Subject: [RHEL5.8 kmod-kvm PATCH 1/2] KVM: Remove ability to assign a device without iommu support
Bugzilla: 770095
RH-Acked-by: Don Dutile <ddutile@redhat.com>
RH-Acked-by: Marcelo Tosatti <mtosatti@redhat.com>
RH-Acked-by: Paul Moore <pmoore@redhat.com>

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=770095
Brew: https://brewweb.devel.redhat.com/taskinfo?taskID=3919196
Upstream commit: 423873736b78f549fbfa2f715f2e4de7e6c5e1e9

This option has no users and it exposes a security hole that we
can allow devices to be assigned without iommu protection.  Make
KVM_DEV_ASSIGN_ENABLE_IOMMU a mandatory option.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
---

 virt/kvm/kvm_main.c |   18 +++++++++---------
 1 files changed, 9 insertions(+), 9 deletions(-)

Signed-off-by: Michal Novotny <mignov@gmail.com>
---
 virt/kvm/kvm_main.c |   18 +++++++++---------
 1 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 02b858a..d0a4266 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -581,6 +581,9 @@ static int kvm_vm_ioctl_assign_device(struct kvm *kvm,
 	struct kvm_assigned_dev_kernel *match;
 	struct pci_dev *dev;
 
+	if (!(assigned_dev->flags & KVM_DEV_ASSIGN_ENABLE_IOMMU))
+		return -EINVAL;
+
 	down_read(&kvm->slots_lock);
 	mutex_lock(&kvm->lock);
 
@@ -634,16 +637,14 @@ static int kvm_vm_ioctl_assign_device(struct kvm *kvm,
 
 	list_add(&match->list, &kvm->arch.assigned_dev_head);
 
-	if (assigned_dev->flags & KVM_DEV_ASSIGN_ENABLE_IOMMU) {
-		if (!kvm->arch.iommu_domain) {
-			r = kvm_iommu_map_guest(kvm);
-			if (r)
-				goto out_list_del;
-		}
-		r = kvm_assign_device(kvm, match);
+	if (!kvm->arch.iommu_domain) {
+		r = kvm_iommu_map_guest(kvm);
 		if (r)
 			goto out_list_del;
 	}
+	r = kvm_assign_device(kvm, match);
+	if (r)
+		goto out_list_del;
 
 out:
 	mutex_unlock(&kvm->lock);
@@ -682,8 +683,7 @@ static int kvm_vm_ioctl_deassign_device(struct kvm *kvm,
 		goto out;
 	}
 
-	if (match->flags & KVM_DEV_ASSIGN_ENABLE_IOMMU)
-		kvm_deassign_device(kvm, match);
+	kvm_deassign_device(kvm, match);
 
 	kvm_free_assigned_device(kvm, match);
 
-- 
1.7.7.4