Re: [PATCH v7 7/7] iommu/vt-d: Check UAPI data processed by IOMMU core

[Auger Eric]

Hi Jacob,

On 7/30/20 2:21 AM, Jacob Pan wrote:
> IOMMU generic layer already does sanity checks UAPI data for version
> match and argsz range under generic information.
> Remove the redundant version check from VT-d driver and check for vendor
> specific data size.
> 
> Signed-off-by: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>

> ---
>  drivers/iommu/intel/iommu.c | 3 +--
>  drivers/iommu/intel/svm.c   | 7 +++++--
>  2 files changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
> index 021f62078f52..7e03cca31a0e 100644
> --- a/drivers/iommu/intel/iommu.c
> +++ b/drivers/iommu/intel/iommu.c
> @@ -5391,8 +5391,7 @@ intel_iommu_sva_invalidate(struct iommu_domain *domain, struct device *dev,
>  	int ret = 0;
>  	u64 size = 0;
>  
> -	if (!inv_info || !dmar_domain ||
> -	    inv_info->version != IOMMU_CACHE_INVALIDATE_INFO_VERSION_1)
> +	if (!inv_info || !dmar_domain)
>  		return -EINVAL;
>  
>  	if (!dev || !dev_is_pci(dev))
> diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c
> index 713b3a218483..55ea11e9c0f5 100644
> --- a/drivers/iommu/intel/svm.c
> +++ b/drivers/iommu/intel/svm.c
> @@ -240,8 +240,11 @@ int intel_svm_bind_gpasid(struct iommu_domain *domain, struct device *dev,
>  	if (WARN_ON(!iommu) || !data)
>  		return -EINVAL;
>  
> -	if (data->version != IOMMU_GPASID_BIND_VERSION_1 ||
> -	    data->format != IOMMU_PASID_FORMAT_INTEL_VTD)
> +	if (data->format != IOMMU_PASID_FORMAT_INTEL_VTD)
> +		return -EINVAL;
> +
> +	/* IOMMU core ensures argsz is more than the start of the union */
> +	if (data->argsz < offsetofend(struct iommu_gpasid_bind_data, vendor.vtd))
>  		return -EINVAL;
Shouldn't you test the vendor flags here? intel_pasid_setup_bind_data()
only checks valid ones but not ~mask.

Thanks

Eric
>  
>  	if (!dev_is_pci(dev))
>