Re: [PATCH 02/18] vchecker: introduce the valid access checker

[Andi Kleen]

js1304@xxxxxxxxx writes:

> From: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>

Looks useful. Essentially unlimited hardware break points, combined
with slab.

Didn't do a full review, but noticed some things below.
> +
> +	buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
> +	if (!buf)
> +		return -ENOMEM;
> +
> +	if (copy_from_user(buf, ubuf, cnt)) {
> +		kfree(buf);
> +		return -EFAULT;
> +	}
> +
> +	if (isspace(buf[0]))
> +		remove = true;

and that may be uninitialized.

and the space changes the operation? That's a strange syntax.


> +	buf[cnt - 1] = '\0';

That's an underflow of one byte if cnt is 0.


-Andi