Running with a readonly root partition
andrew at qemg.org
Fri Jun 13 18:03:29 UTC 2008
As devfs is running by default, it seems to me that
it would be relatively easy to run with a readonly
root partition, assuming that the directories under
which writing is necessary (ie; /tmp, /var, /home)
are located in separate, writable partitions.
The main advantages are that none of the configuration
files or binaries in /etc and /usr (which may still
be on a separate readonly partition) are vulnerable
to attack (even from a local privilege escalation)
without remounting the partition as writable.
This used to be a very common setup in the *NIX
world, so I am surprised to find little to no mention
of it in the archives.
I set up my machine this way a couple of months back,
and have noticed some minor things (some few things
assume a writable /etc, notably including dump(8),
and the boot process update to /etc/motd). Once these
have been rectified by relocating the files and setting
up symlinks, there have been no problems.
My questions are:
- does anyone else do this?
- if not, why not?
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