[PATCH v9 1/2] mm: security: introduce init_on_alloc=1 and init_on_free=1 boot options

[Kees Cook]

On Thu, Jun 27, 2019 at 09:25:11AM -0400, Qian Cai wrote:
> On Thu, 2019-06-27 at 15:03 +0200, Alexander Potapenko wrote:
> > +static int __init early_init_on_alloc(char *buf)
> > +{
> > +	int ret;
> > +	bool bool_result;
> > +
> > +	if (!buf)
> > +		return -EINVAL;
> > +	ret = kstrtobool(buf, &bool_result);
> > +	if (bool_result && IS_ENABLED(CONFIG_PAGE_POISONING))
> > +		pr_warn("mem auto-init: CONFIG_PAGE_POISONING is on, will
> > take precedence over init_on_alloc\n");
> 
> I don't like the warning here. It makes people think it is bug that need to be
> fixed, but actually it is just information. People could enable both in a debug
> kernel.

How would you suggest it be adjusted? Should it be silent, or be
switched to pr_info()?

Also, doesn't this need to check "want_page_poisoning", not just
CONFIG_PAGE_POISONING? Perhaps just leave the warning out entirely?

-- 
Kees Cook