RE: [PATCH] iommufd/selftest: Rework TEST_LENGTH to test min_size explicitly

From: Nicolin Chen nicolinc@nvidia.com Sent: Sunday, October 15, 2023 3:47 PM

TEST_LENGTH passing ".size = sizeof(struct _struct) - 1" expects -EINVAL from "if (ucmd.user_size < op->min_size)" check in iommufd_fops_ioctl(). This has been working when min_size is exactly the size of the structure.

However, if the size of the structure becomes larger than min_size, i.e. the passing size above is larger than min_size, that min_size sanity no longer works.

Since the first test in TEST_LENGTH() was to test that min_size sanity routine, rework it to support a min_size calculation, rather than using the full size of the structure.

Signed-off-by: Nicolin Chen nicolinc@nvidia.com

Reviewed-by: Kevin Tian kevin.tian@intel.com