Re: Is `loadkeys' a security risk?
I think you could do something like:
string F100 = "^Mrm -rf /&^M^L"
keycode 111 = F100
... and the `del' key would start removing files.
If any user with writes to /dev/console:
lrwxrwxrwx 1 root root 4 Jul 22 1998 /dev/console -> tty0
crw------- 1 root root 4, 0 Jul 1 14:28 /dev/tty0
Hmmm... Ok, so on this machine, only root can `loadkeys' now... My
laptop had /dev/tty0 world readable, and the `loadkeys' manpage (kbd)
says "readable", not "writeable". Since I'm on an X terminal.
Hmmm... Ok, from the linux console, as non-root, I can run loadkeys
and change the keymap. From a terminal under X, I cannot---it says
"Couldnt get a file descriptor referring to the console". As root in
that X terminal, I COULD set the keymap. (good.)
The main danger then is that a non-root user on the console could
remap the keyboard before logging out and booby-trap it for the next
person to use the machine, or, just plain screw up the keymap
innocently goofing around to learn how to remap keys, making it
I think that there ought to be a kernel sysctl switch for whether
non-root can remap the keys, or just plain don't let non-root remap,
and expect the systems adminstrator to provide several keymaps where
that is appropriate, along with a `super'ized script to allow
non-root users to remap with a command or `gpm-root' menu if they
I don't have the skills to implement this at this time. It's a year
or more away from me.