Re: [kernel-hardening][RFC PATCH v2 01/12] x86: add PAX_REFCOUNT support

[Greg KH <greg@kroah.com>]

On Thu, Dec 17, 2015 at 12:55:44PM -0500, David Windsor wrote:
> On Thu, Dec 17, 2015 at 12:16 PM, Greg KH <gregkh@linuxfoundation.org> wrote:
> > On Thu, Dec 17, 2015 at 09:57:39AM -0500, David Windsor wrote:
> >> --- a/include/linux/sched.h
> >> +++ b/include/linux/sched.h
> >> @@ -749,6 +749,17 @@ struct signal_struct {
> >>  #ifdef CONFIG_TASKSTATS
> >>       struct taskstats *stats;
> >>  #endif
> >> +
> >> +#ifdef CONFIG_GRKERNSEC
> >> +     u32 curr_ip;
> >> +     u32 saved_ip;
> >> +     u32 gr_saddr;
> >> +     u32 gr_daddr;
> >> +     u16 gr_sport;
> >> +     u16 gr_dport;
> >> +     u8 used_accept:1;
> >> +#endif
> >> +
> >
> > Why is this here in this patch?
> >
> 
> For pax_report_refcount_overflow in fs/exec.c:
> 
> 1754: if (current->signal->curr_ip)
> 
> This is guarded by CONFIG_PAX_REFCOUNT, which, as it stands, should
> depend on CONFIG_GRKERNSEC.  The Kconfig options likely need to
> change, depending on the naming of these features moving forward.

But that has nothing to do with this patch, and as that config option
isn't present in the kernel at this point in time, this change is not
needed at all, right?

Or am I missing something?

thanks,

greg k-h