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

[Jacob Pan]

On Thu, 13 Aug 2020 11:19:46 +0200
Auger Eric <eric.auger@xxxxxxxxxx> wrote:

> 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.
> 
Yes, vendor flags should be tested to make sure there is no undefined
flags being used.

Thanks!

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

[Jacob Pan]