[systemd-devel] PrivateDevices with more than basic set of devices?

[Simon McVittie]

On 24/01/15 10:09, Topi Miettinen wrote:
> For example, smartd only needs access to /dev/sd*.

Let me spell that differently: smartd "only" needs the ability to make
arbitrary filesystem changes, defeating any possible configurable
security mechanism.

If you give it access to /dev/sd* but not to other devices, what
security or safety have you actually gained, compared with giving it all
of /dev?

Admittedly, there are better examples, like saned only needing access to
USB scanners (plus SCSI scanners, serial ports and parallel ports if you
care about older hardware). I suspect device permissions are a rather
better answer for finer-grained access control than "all or nothing",
though.

    S