Back To Basics: Avoiding Recursive Alias Disasters On Linux And Unix

Aug 14, 2008, 22:04 (2 Talkback[s])
(Other stories by Mike Tremell)

[ Thanks to Mike Golvach for this link. ]

"The infinite recursion problem with aliases closely parallels a very simple exploit that can be run in a simple shell script. The ends are the same, and the means are closely related. For instance, if you create a shell script called "ls," with the contents:

#!/bin/sh

ls;sleep 1500000000

"and manage to get that in a user's PATH before the real /bin/ls (or /usr/bin/ls), it'll ratchet up the number of open processes and filehandles very quickly. If let sit, it will take down any machine of any size eventually."

Complete Story

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