Re: Odd behaviour on Bash 2.04 and 2.05

[yap_noel]

Ooh, I think I understand this one.

Whenever you do this, you define a function ':' (that recursively calls
itself twice in the background) then you call that function.  Can the gurus
confirm this?

Don't do this, it'll bring down any system, not just Linux.

Noel

Hi,

A friend of mine stumbled over a sequence of characters with which he could
easily take down a running Debian and Suse (7.2) Linux 2.4 system.

Problem description:

- Login in to Linux, start bash if it's not default already, and enter the
following bogus command:

:(){ :|:&};:

- Press enter a couple of times, wait, and after a while you will get:

bash: fork: Cannot allocate memory
bash: fork: Cannot allocate memory
bash: fork: Cannot allocate memory
bash: fork: Cannot allocate memory
bash: fork: Cannot allocate memory
bash: fork: Cannot allocate memory
bash: pipe error: Too many open files in system
bash: pipe error: Too many open files in system
bash: pipe error: Too many open files in system
bash: pipe error: Too many open files in system
...
indefinetly until your linux box runs out of swap space and needs to be
hard-
reset.


Tested on:
GNU bash, version 2.05.0(1)-release (i386-suse-linux)
Copyright 2000 Free Software Foundation, Inc.

GNU bash, version 2.04.0(1)-release (i386-suse-linux)
Copyright 1999 Free Software Foundation, Inc.

Is this problem specific to Suse? Is it a possible bug?

Thanks,
Chris

ps: Please CC me for replies as I am not on the list/newsgroup


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