OpenBSD process maps

Question

I am using OpenBSD 7.7.

So I know that procfs is not mounted on /proc, and I need to use sysctl to fetch process maps. But this fails as I am not running as a root user. The secure level is set to 1 so that is why I can't use sysctl without root. But even procmap is not permitted as a root user.

Is there any way I can fetch the process maps without root?

Answer 1

If securelevel is set to 1 you simply can't access /dev/kmem (nor /dev/mem), which is used by procmap. And you also can't change securelevel back to 0 on-the-fly (you'd need to set it in /etc/sysctl.conf and reboot). From securelevel(7):

1 Secure mode
     -   default mode when system is multi-user
     -   securelevel may no longer be lowered except by init
     -   /dev/mem and /dev/kmem cannot be opened
    (...)
     -   the hw.allowpowerdown, kern.allowkmem, kern.utc_offset,
         net.inet.ip.sourceroute, and machdep.kbdreset sysctl(8)
         variables may not be changed

Furthermore, procmap(1) says that:

procmap requires the ability to open /dev/kmem which may be restricted
based upon the value of the kern.allowkmem sysctl(8).

and on my machine ls -l /dev/kmem shows that

crw-r-----  1 root  kmem  2, 1 May 14 16:37 /dev/kmem

So to be able to use procmap, you would need:

1. to set kern.securelevel=0 in /etc/sysctl.conf, and reboot the machine,
2. set kern.allowkmem to 1 (or add this to /etc/sysctl.conf, while you're at it), and
3. be either root or a user in the kmem group to be able to access /dev/kmem.

So no, there is no way you can fetch the process maps without root, nor without fiddling with some knobs.