Re: [PATCH] sysctl: permission check based on capability not euid

* Stephen Hemminger (stephen.hemminger@vyatta.com) wrote:

This patch modifies the permission checks for sysctl's from being based on uid=0 (root)
to use the capability system. This matches the behavior of other OS's using sysctl's
and capabilities. Linux has tried to get away from using uid=0 for security overrides
and use capabilities instead. 

I was working on Quagga enhancement that involved enabling a sysctl, and it didn't
work because is a safe daemon and drops privileges and resets its real/effective uid
after initialization; it then re-enables only the capabilities when it needs to
do some privileged operation. This wouldn't work because sysctl's were still using
the root based permission check. The existing code in quagga to enable ip forwarding
doesn't work for the same reason.

I don't think CAP_SYS_ADMIN makes sense for net.*, for example.