[arch-general] Policy about packages and file capabilities

[Damjan Georgievski]

>> What's the policy about capabilities for executables in Arch packages?
>
> I _guess_ that capabilities are used to avoid SUID binaries when this is
> secure.

well, also, unless you set capabilities on the executable a process
can't have capabilities when a non-root process execs the executable
-- that is until the ambient capabilities are supported in the kernel
and systemd
https://lwn.net/Articles/651052/ (afaik in 4.3)

>> I'm asking since in my setup I'm running wpa_supplicant as the
>> 'nobody' user, but I let it keep the NET_ADMIN and NET_RAW
>> capabilities (excerpt from the .service file):
>
> Read the caveat here: https://w1.fi/cgit/hostap/plain/wpa_supplicant/README .
> Basically, you'll need a special user/group for executing
> /usr/bin/wpa_supplicant.

right, I  think that too would need to be done in a proper package.
I'd rather make it 750, and root/wpa_supplicant

> In general, why is this necessary? What kind of attack (besides DoS) is
> possible against wpa_supplicant?

there have been buffer overflows etc. in wpa supplicant, not good for
a root process.
https://www.google.com/search?q=wpa_supplicant+CVE&ie=utf-8&oe=utf-8

-- 
damjan