Function check_fs_node_mknod_access 

pub fn check_fs_node_mknod_access(
    current_task: &CurrentTask,
    parent: &FsNode,
    mode: FileMode,
    name: &FsStr,
    device_id: DeviceType,
) -> Result<(), Errno>

Validate that current_task has permission to create a new special file, socket or pipe, in the parent directory, and with the specified file mode and device_id. For consistency any calls to mknod() with a file mode specifying a regular file will be validated by check_fs_node_create_access() rather than by this hook. Corresponds to the inode_mknod() LSM hook.