On Mon, Aug 07, 2023 at 03:08:29PM +0000, Liu, Yi L wrote:
From: Liu, Yi L yi.l.liu@intel.com Sent: Monday, July 24, 2023 7:14 PM
+static int intel_nested_cache_invalidate_user(struct iommu_domain *domain,
void *user_data)+{
- struct iommu_hwpt_vtd_s1_invalidate_desc *req = user_data;
- struct iommu_hwpt_vtd_s1_invalidate *inv_info = user_data;
- struct dmar_domain *dmar_domain = to_dmar_domain(domain);
- unsigned int entry_size = inv_info->entry_size;
- u64 uptr = inv_info->inv_data_uptr;
- u64 nr_uptr = inv_info->entry_nr_uptr;
- struct device_domain_info *info;
- u32 entry_nr, index;
- unsigned long flags;
- int ret = 0;
- if (get_user(entry_nr, (uint32_t __user *)u64_to_user_ptr(nr_uptr)))
return -EFAULT;- for (index = 0; index < entry_nr; index++) {
ret = copy_struct_from_user(req, sizeof(*req),u64_to_user_ptr(uptr + index *entry_size),
entry_size);If continuing this direction then the driver should also check minsz etc. for struct iommu_hwpt_vtd_s1_invalidate and iommu_hwpt_vtd_s1_invalidate_desc since they are uAPI and subject to change.
Then needs to define size in the uapi data structure, and copy size first and check minsz before going forward. How about the structures for hwpt alloc like struct iommu_hwpt_vtd_s1? Should check minsz for them as well?
Assuming that every uAPI data structure needs a min_size, we can either add a structure holding all min_sizes like iommufd main.c or have another xx_min_len in iommu_/domain_ops.
Currently, we have the union of structures in iommu.h and also a xx_data_len in iommu_ops. So, neither of the two places seem to be optimal from my p.o.v... any suggestion?
Also, alloc allows data_len=0, so a min_size check will be only applied to data_len > 0 case.
Thanks Nic