Re: [PATCH] vsprintf: avoid misleading "(null)" for %px

[Tobin C. Harding]

On Mon, Feb 05, 2018 at 09:36:03AM -0800, Randy Dunlap wrote:
> On 02/05/2018 08:49 AM, Steven Rostedt wrote:
> > On Mon, 5 Feb 2018 16:22:19 +0100
> > Adam Borowski <kilobyte@xxxxxxxxxx> wrote:
> > 
> >> My change touches %px only, where your concern doesn't apply.
> >>
> >> You're right, though, when it comes to %pK:
> >>     printk("%%pK: %pK, %%px: %px\n", 0, 0);
> >> says
> >>     %pK: 00000000ba8bdc0a, %px: 0000000000000000
> >>
> >> So what should we do?  Avoid hashing 0?  Print a special value?
> > 
> > My personal opinion is that NULL should stay NULL and not be hashed.
> > What security issue could be leaked by a NULL? I'm not a security
> > person, that's a real question.
> 
> Agree.

While these views seem valid I don't think we are going to get much
love trying to change %pK to give a smidgen more information when %pK is
arguably out of favour :)

	Tobin