Re: Tar extraction: Member name contains `..'

[Eli Zaretskii]

> From: Fred Ma <address@hidden>
> Newsgroups: gnu.utils.help,gnu.utils.bug
> Date: 18 Jul 2004 22:33:27 GMT
> 
> I've been googling and google-grouping the gnu tar problem 
> where file extraction generates the error message:
> 
>    Member name contains `..'
> 
> It seems like one can capture files with paths having "..", but not
> extract them.

It could well be a bug in the Cygwin port of Tar.

> I am using version 1.13.25 on Cygwin, but this problem
> seems to be many years old, and span many target OS's.

I doubt that.  1.13.25 is quite new (1.14 was released in May this
year), and I cannot find this string in Tar 1.12.

>    1. Explicitly disallow the inclusion of such files in the tar file
>       through the use of an informative error message, and don't
>       bother using up the bytes to embed such a file in the tar
>       archive (since it can't be retrieved anyway).
> 
>    2. Allow the inclusion of such files with a warning.  Warn of the
>       presence of such files in the extraction, and do not extract
>       them by default.  But do allow this default to be overridden.

Can you explain why this is a problem?  I don't see why having two
dots in a row in a file name would prevent it from being extracted,
including on Windows.

P.S. I'm not the official maintainer of GNU Tar, but I hacked through
its sources quite a bit.