On Tue, Oct 10, 2017 at 09:06:50PM -0700, Joe Perches wrote:
> On Wed, 2017-10-11 at 14:48 +1100, Tobin C. Harding wrote:
> > Currently there are many places in the kernel where addresses are being
> > printed using an unadorned %p. Kernel pointers should be printed using
> > %pK allowing some control via the kptr_restrict sysctl. Exposing addresses
> > gives attackers sensitive information about the kernel layout in memory.
> []
> > diff --git a/lib/vsprintf.c b/lib/vsprintf.c
> []
> > @@ -1591,6 +1591,35 @@ char *device_node_string(char *buf, char *end,
> > struct device_node *dn,
> > return widen_string(buf, buf - buf_start, end, spec);
> > }
> >
> > +static long get_random_odd_long(void)
> > +{
> > + long val = 0;
> > +
> > + while((val & 1) == 0) {
> > + val = get_random_long();
> > + }
> > +
> > + return val;
> > +}
>
> Perhaps
>
> static long get_random_odd_long(void)
> {
> return get_random_long() | 1L;
> }
>
Nice.
thanks,
Tobin.
