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;
}

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