From 423873736b78f549fbfa2f715f2e4de7e6c5e1e9 Mon Sep 17 00:00:00 2001 From: Alex Williamson Date: Tue, 20 Dec 2011 21:59:03 -0700 Subject: [PATCH] KVM: Remove ability to assign a device without iommu support 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 Signed-off-by: Marcelo Tosatti --- Documentation/virtual/kvm/api.txt | 3 +++ virt/kvm/assigned-dev.c | 18 +++++++++--------- 2 files changed, 12 insertions(+), 9 deletions(-) diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 7945b0bd35e2..ee2c96b3ba5a 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -1151,6 +1151,9 @@ following flags are specified: /* Depends on KVM_CAP_IOMMU */ #define KVM_DEV_ASSIGN_ENABLE_IOMMU (1 << 0) +The KVM_DEV_ASSIGN_ENABLE_IOMMU flag is a mandatory option to ensure +isolation of the device. Usages not specifying this flag are deprecated. + 4.49 KVM_DEASSIGN_PCI_DEVICE Capability: KVM_CAP_DEVICE_DEASSIGNMENT diff --git a/virt/kvm/assigned-dev.c b/virt/kvm/assigned-dev.c index 3ad0925d23a9..a251a28f79c7 100644 --- a/virt/kvm/assigned-dev.c +++ b/virt/kvm/assigned-dev.c @@ -487,6 +487,9 @@ 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; + mutex_lock(&kvm->lock); idx = srcu_read_lock(&kvm->srcu); @@ -544,16 +547,14 @@ 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: srcu_read_unlock(&kvm->srcu, idx); @@ -593,8 +594,7 @@ 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); -- 2.30.2