Re: [PATCH 07/12] iommufd: Add IOMMU_HWPT_INVALIDATE

Jason Gunthorpe
2023-03-20T12:50:49Z

On Tue, Mar 14, 2023 at 04:18:21AM +0000, Liu, Yi L wrote:
> > From: Jason Gunthorpe <jgg@nvidia.com>
> > Sent: Saturday, March 11, 2023 1:50 AM
> >
> > On Thu, Mar 09, 2023 at 12:09:05AM -0800, Yi Liu wrote:
> > > +int iommufd_hwpt_invalidate(struct iommufd_ucmd *ucmd)
> > > +{
> > > + struct iommu_hwpt_invalidate *cmd = ucmd->cmd;
> > > + struct iommufd_hw_pagetable *hwpt;
> > > + u64 user_ptr;
> > > + u32 user_data_len, klen;
> > > + int rc = 0;
> > > +
> > > + /*
> > > + * For a user-managed HWPT, type should not be
> > IOMMU_HWPT_TYPE_DEFAULT.
> > > + * data_len should not exceed the size of
> > iommufd_invalidate_buffer.
> > > + */
> > > + if (cmd->data_type == IOMMU_HWPT_TYPE_DEFAULT || !cmd-
> > >data_len ||
> > > + cmd->data_type >=
> > ARRAY_SIZE(iommufd_hwpt_invalidate_info_size))
> > > + return -EOPNOTSUPP;
> >
> > This needs to do the standard check for zeros in unknown trailing data
> > bit. Check that alloc does it too
>
> Maybe it has been covered by the copy_struct_from_user(). Is it?

Yes

Jason