[PATCH v5 09/15] iommu/vt-d: Check ownership for PASIDs from user-space

Liu Yi L
2020-07-12T11:16:13Z

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@intel.com>
CC: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Eric Auger <eric.auger@redhat.com>
Cc: Jean-Philippe Brucker <jean-philippe@linaro.org>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Liu Yi L <yi.l.liu@intel.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
---
drivers/iommu/intel/iommu.c | 10 ++++++++++
drivers/iommu/intel/svm.c | 7 +++++--
2 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 4d54198..a9504cb 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -5436,6 +5436,7 @@ 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) {
@@ -5456,6 +5457,15 @@ intel_iommu_sva_invalidate(struct iommu_domain *domain, struct device *dev,
(inv_info->granu.addr_info.flags & IOMMU_INV_ADDR_FLAGS_PASID))
pasid = inv_info->granu.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 d2c0e1a..212dee0 100644
--- a/drivers/iommu/intel/svm.c
+++ b/drivers/iommu/intel/svm.c
@@ -319,7 +319,7 @@ 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;
@@ -436,6 +436,7 @@ int intel_svm_unbind_gpasid(struct iommu_domain *domain,
struct device *dev, ioasid_t pasid)
{
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;
@@ -443,8 +444,10 @@ int intel_svm_unbind_gpasid(struct iommu_domain *domain,
if (WARN_ON(!iommu))
return -EINVAL;

+ 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