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Date: Sun, 05 Jul 2009 15:45:40 -0700
From: Ian Kelling <smallnow@gmail.com>
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Subject: Re: ssh-host-config eval password bug
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Eric Blake wrote:
> The eval is still reasonable, but with proper quoting:
> 
> if eval cygrunsrv ... -y tcpip "${cygwin_env}"

No, thats not true. It is impossible to safely eval arbitrary user input.
Your simple quote doesn't help much:

# x="ok;ls"
# eval echo "{$x}"

For more in depth information, read this:
http://mywiki.wooledge.org/BashFAQ/048

- Ian Kelling


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