iommufd: Check the domain owner of the parent before creating a nesting domain

This check was missed, before we can pass a struct iommu_domain to a
driver callback we need to validate that the domain was created by that
driver.

Fixes: bd529dbb661d ("iommufd: Add a nested HW pagetable object")
Link: https://patch.msgid.link/r/0-v1-c8770519edde+1a-iommufd_nesting_ops_jgg@nvidia.com
Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

diff --git a/drivers/iommu/iommufd/hw_pagetable.c b/drivers/iommu/iommufd/hw_pagetable.c
index aefde4443671ed8d7745214ba966a1eaeb64cd36..d06bf6e6c19fd207a1b84d018920865b12a5b571 100644 (file)
--- a/drivers/iommu/iommufd/hw_pagetable.c
+++ b/drivers/iommu/iommufd/hw_pagetable.c
@@ -225,7 +225,8 @@ iommufd_hwpt_nested_alloc(struct iommufd_ctx *ictx,
        if ((flags & ~IOMMU_HWPT_FAULT_ID_VALID) ||
            !user_data->len || !ops->domain_alloc_user)
                return ERR_PTR(-EOPNOTSUPP);
-       if (parent->auto_domain || !parent->nest_parent)
+       if (parent->auto_domain || !parent->nest_parent ||
+           parent->common.domain->owner != ops)
                return ERR_PTR(-EINVAL);
 
        hwpt_nested = __iommufd_object_alloc(