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Date: Sat, 2 Oct 2004 16:12:11 -0400
From: David Schultz <das@FreeBSD.ORG>
To: Michael Reifenberger <mike@Reifenberger.com>
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cc: freebsd-hackers@FreeBSD.ORG
Subject: Re: Protection from the dreaded "rm -fr /"
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On Sat, Oct 02, 2004, Michael Reifenberger wrote:
> On Sat, 2 Oct 2004, David Schultz wrote:
> ...
> >Do you also want to be able to swap to the root partition while
> >it's mounted?  We can bring back that feature, too.  But
> >personally, I don't see anything wrong with the view that
> >operations that are guaranteed to shoot people in the foot should
> >be disallowed.
> >
> 
> Every anti foot shooting takes time to check for.
> A strncmp for every arg is maybe ok. Traversing the tree for realpath is 
> not.
> The job for `rm` is to remove whatever it is given to get removed.
> As fast as possible. Nothing else.

Sigh.  The original patch that just used strcmp() wouldn't have
increased the time to execute rm by more than a few hundred
nanoseconds.