Re: dmidecode and access to /dev/mem denied

[Stuart Henderson]

On 2016-10-21, Kapetanakis Giannis <bil...@edu.physics.uoc.gr> wrote:
> Hi,
>
> # dmidecode 
> # dmidecode 3.0
> Scanning /dev/mem for entry point.
> /dev/mem: Operation not permitted
>
> I guess this is similar to 
> http://marc.info/?l=openbsd-misc&m=147575799412450&w=2
>
> where stu@ said:
> "Kernel virtual memory access is no longer permitted by the kernel on a
> normally running system.  The relevant parts of net-snmp will need to be
> disabled or rewritten"

sthen@ != stu@

> Any way to get through that and read DMI entries?

There is a sysctl kern.allowkmem:

   KERN_ALLOWKMEM
           Allow userland processes access to /dev/kmem.  When running with a
           securelevel(7) greater than 0, this variable may not be changed.