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Subject: Re: tar: symlinks unpacked to empty files (tar security problem?)
From: "Yaakov (Cygwin/X)" <yselkowitz AT users DOT sourceforge DOT net>
To: cygwin <cygwin AT cygwin DOT com>
In-Reply-To: <20100704171709.GA12616@ednor.casa.cgf.cx>
References: <1278237042 DOT 6012 DOT 15 DOT camel AT YAAKOV04>	 <20100704171709 DOT GA12616 AT ednor DOT casa DOT cgf DOT cx>
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Date: Sun, 04 Jul 2010 14:46:32 -0500
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On Sun, 2010-07-04 at 13:17 -0400, Christopher Faylor wrote:
> That's because of the way that tar handles symlinks.  If you have a
> reference to an absolute path, tar makes a zero-length regular file
> placeholder.  Then when it is done extracting, tar is supposed to remove
> this file and create the real symlink.  However, the test to make sure
> that it is ok to do this was broken by a recent DLL change.  The inode
> returned the first time that the file was created was != the inode when
> the file is checked later.  So tar thought that the zero-length file was
> modified and silently decided not to create the symlink.
> 
> I've fixed the cygwin problem - it should be in the next snapshot.

It appears to be working with 20100704 snapshot.  Thanks for the quick
response.


Yaakov



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