[PATCH v2 09/15] iommu/vt-d: Check ownership for PASIDs from user-space

From: Liu Yi L
Date: Thu Jun 11 2020 - 08:09:57 EST


When an IOMMU domain with nesting attribute is used for guest SVA, a
system-wide PASID is allocated for binding with the device and the domain.
For security reason, we need to check the PASID passsed from user-space.
e.g. page table bind/unbind and PASID related cache invalidation.

Cc: Kevin Tian <kevin.tian@xxxxxxxxx>
CC: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>
Cc: Alex Williamson <alex.williamson@xxxxxxxxxx>
Cc: Eric Auger <eric.auger@xxxxxxxxxx>
Cc: Jean-Philippe Brucker <jean-philippe@xxxxxxxxxx>
Cc: Joerg Roedel <joro@xxxxxxxxxx>
Cc: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
Signed-off-by: Liu Yi L <yi.l.liu@xxxxxxxxx>
Signed-off-by: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>
---
drivers/iommu/intel-iommu.c | 10 ++++++++++
drivers/iommu/intel-svm.c | 6 ++++--
2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 2d59a5d..25650ac 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -5433,6 +5433,7 @@ intel_iommu_sva_invalidate(struct iommu_domain *domain, struct device *dev,
int granu = 0;
u64 pasid = 0;
u64 addr = 0;
+ void *pdata;

granu = to_vtd_granularity(cache_type, inv_info->granularity);
if (granu == -EINVAL) {
@@ -5452,6 +5453,15 @@ intel_iommu_sva_invalidate(struct iommu_domain *domain, struct device *dev,
(inv_info->addr_info.flags & IOMMU_INV_ADDR_FLAGS_PASID))
pasid = inv_info->addr_info.pasid;

+ pdata = ioasid_find(dmar_domain->ioasid_sid, pasid, NULL);
+ if (!pdata) {
+ ret = -EINVAL;
+ goto out_unlock;
+ } else if (IS_ERR(pdata)) {
+ ret = PTR_ERR(pdata);
+ goto out_unlock;
+ }
+
switch (BIT(cache_type)) {
case IOMMU_CACHE_INV_TYPE_IOTLB:
/* HW will ignore LSB bits based on address mask */
diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c
index bf55e2f..49059c1 100644
--- a/drivers/iommu/intel-svm.c
+++ b/drivers/iommu/intel-svm.c
@@ -332,7 +332,7 @@ int intel_svm_bind_gpasid(struct iommu_domain *domain, struct device *dev,
dmar_domain = to_dmar_domain(domain);

mutex_lock(&pasid_mutex);
- svm = ioasid_find(INVALID_IOASID_SET, data->hpasid, NULL);
+ svm = ioasid_find(dmar_domain->ioasid_sid, data->hpasid, NULL);
if (IS_ERR(svm)) {
ret = PTR_ERR(svm);
goto out;
@@ -450,6 +450,7 @@ int intel_svm_unbind_gpasid(struct iommu_domain *domain,
struct iommu_gpasid_unbind_data *data)
{
struct intel_iommu *iommu = intel_svm_device_to_iommu(dev);
+ struct dmar_domain *dmar_domain;
struct intel_svm_dev *sdev;
struct intel_svm *svm;
int ret = -EINVAL;
@@ -464,9 +465,10 @@ int intel_svm_unbind_gpasid(struct iommu_domain *domain,
return -EINVAL;

pasid = data->pasid;
+ dmar_domain = to_dmar_domain(domain);

mutex_lock(&pasid_mutex);
- svm = ioasid_find(INVALID_IOASID_SET, pasid, NULL);
+ svm = ioasid_find(dmar_domain->ioasid_sid, pasid, NULL);
if (!svm) {
ret = -EINVAL;
goto out;
--
2.7.4