Re: cp -p error when directory security is modified from Windows

[Bob Proulx]

Greg Aloe wrote:
> I'm not sure what information to relay to you, so I'll do the best I
> can, and let you follow up with questions.

First thanks for reporting bugs and problems.  However, I was just a
little confused as to the exact problem you were trying to report.  If
I missed the mark then send a correction.

> Linux hostname 2.4.21-193-smp #1 SMP Wed Jan 21 18:41:44 UTC 2004 x86_64
> x86_64 x86_64 GNU/Linux
> 
> Linux hostname 2.4.18 #14 SMP Mon Feb 10 15:36:47 EST 2003 i686 unknown
> 
> Works on Solaris:
> 
> SunOS hostname 5.6 Generic_105181-33 sun4u sparc SUNW,Ultra-Enterprise

Okay.  (Is SunOS an NFS fileserver in your example?  You did not say
but I am guessing that is true.)

> Now, here's the bug.
>       [hostname:/home/galoe/trash]128 % ls -ld testdir
>       drwxr-xr-x    2 galoe    users        4096 Jul 27 11:06 testdir
>       [hostname:/home/galoe/trash]129 % cp -p
> /devel/A/nightly/matlabinternetfile.txt testdir/

Your word wrapping here is unfortunate and makes the examples hard to
follow.  In the future if you could make your examples verbatim it
would be easier to read.  I needed to do a lot of trimming and
*imagining* what it must have looked like to you.

>       -rw-r--r--    1 galoe    users       20051 Oct 15  2003
> matlabinternetfile.txt
> 
> Now I'll remove the file so I can show you the bug:
>       [hostname:/home/galoe/trash]131 % rm
> testdir/matlabinternetfile.txt
>       [hostname:/home/galoe/trash]132 % ls testdir/

I don't see any problems yet.  Should I?

> Now, since my Windows machine has access to this network, I can modify
> the security of the directory.  Note, however, that I'm not even
> changing anything.  I'm just checking a box, unchecking it, and clicking
> Apply.  Here are the exact steps from Windows XP Pro 2002 with Service
> Pack 2:

This is not the right list to talk about MS-Windows problems.
Probably the better list would be the Cygwin list.

  http://cygwin.com

> ...a bunch of MS stuff deleted...not appropriate for this list...
>
> Now, back on Linux, let's look at the permissions and notice they didn't
> change:
> 
>       [hostname:/home/galoe/trash]133 % ls -ld testdir
>       drwxr-xr-x    2 galoe    users        4096 Jul 27 11:06 testdir

This is all that matters here.

> Now, try to copy a file owned by someone else using -p, and notice the
> error, and that the permissions and ownership are incorrect:
> 
>       [hostname:/home/galoe/trash]134 % cp -p
> /devel/A/nightly/matlabinternetfile.txt testdir/
> 
>       cp: setting permissions for `testdir/matlabinternetfile.txt':
> Operation not permitted

Whether this is allowed or not is based upon your kernel security
poilcy.  See this FAQ for more information.

  http://www.gnu.org/software/coreutils/faq/

Look for "Why can only root chown files?"

>       [hostname:/home/galoe/trash]135 % ls -l testdir/
>       -rwxr-xr-x    1 batserve users       20051 Oct 15  2003
> matlabinternetfile.txt

Apparently you are running a security policy on that filesystem which
is different from the modern norm.  Normally you would not have had
permission to change the ownership of that file to user "batserve"
because you are not that user.  But because it did allow you to change
the ownership then it no longer allowed you to change the permissions
because you did not own the file.  That is the source of the error
message.

> If this has already been reported, please tell me where to find the bug
> report.

So far in this discussion we don't know the exact location of the
bug.  To me it looks like a bug in your system to allow this behavior
this way.  But the jury is still out.

What type of filesystem are you working in?  Is it a local filesystem
or a networked filesystem?  I am guessing it is a networked
filesystem.  In which case the problem seems to be on your fileserver.
However, one persons bug is another persons feature.  The legacy
behavior of SysV systems is to allow chown from non-root users.  So I
am guessing that your SunOS machine is an NFS fileserver and chown is
allowed there and you are working from your GNU/Linux machine onto
your SunOS fileserver.  Correct?

I will trail off here and allow others to comment further.

Bob