Re: [AppArmor 01/41] Pass struct vfsmount to the inode_create LSM hook

Pavel Machek
2007-05-29T14:49:09Z

Hi!

> > If we want "/etc/shadow" to be the only way to access the shadow file
> > we could label the data with "/etc/shadow". Any attempts to access
> > this data using a renamed file or link would be denied (attempts to
> > link or rename could also be denied).
> Eloquently put.
>
> AppArmor actually does something similar to this, by mediating all of
> the ways that you can make an alias to a file. These are:
...
> * Hard links: AppArmor explicitly mediates permission to make a hard

Unfortunately, aparmor is by design limited to subset of distro
(network daemons). Unfortunately, some other programs (passwd, vi)
routinely make hardlinks. So AA mediating hardlink is not enough, as
vi will happily hardlink /etc/shadow into /etc/.vi-shadow-1234.

Pavel
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