[TUHS] There is turmoil in Linux-land - When did rm first avoid going upwards?

Noel Chiappa jnc at mercury.lcs.mit.edu
Tue Apr 25 08:06:03 AEST 2017


    > From: Josh Good

    > Would the command "cd /tmp ; rm -rf .*" be able to kill a V6 ... system?

Looking at the vanilla 'rm' source for V6, it cannot/does not delete
directories; one has to use the special 'rmdir' command for that. But,
somewhat to my surprise, it does support both the '-r' and '-f' flags, which I
thought were later. (Although not as 'stacked' flags, so you'd have to say
'rm -r -f'.)

So, assuming one did that, _and_ (important caveat!) _performed that command
as root_, it probably would empty out the entire directory tree. (I checked,
and "cd /tmp ; echo .*" evaluates to ". .." on V6.

	Noel


More information about the TUHS mailing list