Re: [PATCH v7 13/28] iommufd/viommu: Add IOMMUFD_CMD_HW_QUEUE_ALLOC ioctl

On Thu, Jun 26, 2025 at 12:34:44PM -0700, Nicolin Chen wrote:

+static struct iommufd_access * +iommufd_hw_queue_alloc_phys(struct iommu_hw_queue_alloc *cmd,

• 	    struct iommufd_viommu *viommu, phys_addr_t *base_pa)
  

+{

• struct iommufd_access *access;
• struct page **pages;
• int max_npages, i;

These types are not int..

• u64 offset;
• int rc;
• offset =

• cmd->nesting_parent_iova - PAGE_ALIGN(cmd->nesting_parent_iova);
  

This is a u64

• max_npages = DIV_ROUND_UP(offset + cmd->length, PAGE_SIZE);

Length is a u64

It should be

/* DIV_ROUND_UP(offset + cmd->length, PAGE_SIZE) */ if (check_add_overflow(offset, cmd->length, &length)) return -ERANGE; if (check_add_overflow(length, PAGE_SIZE-1, &length)) return -ERANGE; if (length > SIZE_MAX) return -ERANGE; max_npages = length / PAGE_SIZE;

And then max_npages and i should be size_t.

Otherwise it looks OK

Reviewed-by: Jason Gunthorpe jgg@nvidia.com

Jason