Re: [PATCH v2 4/8] cxl/mem: Add basic IOCTL interface

[Al Viro <viro@xxxxxxxxxxxxxxxxxx>]

On Sun, Feb 14, 2021 at 11:50:12PM +0000, Al Viro wrote:
> 	check that len is reasonable
> 	p = kmalloc(offsetof(struct foo, string[len]), GFP_KERNEL);
> 	copy_from_user(p, user_object, len);
			offsetof(struct foo, string[len]), that is