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Re: New ELF packages available



> > 	Changed ld-linux.so to map files with MAP_DENYWRITE to
> > 	keep them from being changed while the file is in use
> > 	(Rick Sladkey).
> 
> Woa there !  Under what circumstances can I map a file with
> MAP_DENYWRITE ?
> 
> If I can prevent a user updating their files simply by opening them
> for reading and then mmapping them with funny options there is a bug
> in the kernel.
> 
> It seems to me that this feature is not even required.  In general
> shared libraries are only created by (and hence writeable by) the
> sysadmin (who should follow the library upgrade release notes) or by
> clueful users (who deserve what they get if they write to in-use
> libraries).

I don't understand your objection.  The kernel already does this for
a.out binaries and libraries and the ELF dynamic linker.  How else do
you propose to prevent binaries/libraries which are in use from being
opened for writing?

If you feel this is a permission problem, you should take it up with
Linus.  It's been in the kernel for quite some time.

David
-- 
David Engel                        Optical Data Systems, Inc.
david@ods.com                      1101 E. Arapaho Road
(214) 234-6400                     Richardson, TX  75081


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