On Fri, Oct 20, 2023 at 11:28:02PM +0100, Joao Martins wrote:
> +static int iommufd_test_dirty(struct iommufd_ucmd *ucmd,
> + unsigned int mockpt_id, unsigned long iova,
> + size_t length, unsigned long page_size,
> + void __user *uptr, u32 flags)
> +{
> + unsigned long i, max = length / page_size;
> + struct iommu_test_cmd *cmd = ucmd->cmd;
> + struct iommufd_hw_pagetable *hwpt;
> + struct mock_iommu_domain *mock;
> + int rc, count = 0;
> +
> + if (iova % page_size || length % page_size ||
> + (uintptr_t)uptr % page_size)
> + return -EINVAL;
> +
> + hwpt = get_md_pagetable(ucmd, mockpt_id, &mock);
> + if (IS_ERR(hwpt))
> + return PTR_ERR(hwpt);
> +
> + if (!(mock->flags & MOCK_DIRTY_TRACK)) {
> + rc = -EINVAL;
> + goto out_put;
> + }
> +
> + for (i = 0; i < max; i++) {
> + unsigned long cur = iova + i * page_size;
> + void *ent, *old;
> +
> + if (!test_bit(i, (unsigned long *) uptr))
> + continue;
Is it okay to test_bit on a user pointer/page? Should we call
get_user_pages or so?
Thanks
Nicolin
