Re: Getting full path from dentry in LSM hooks

[Andrea Arcangeli <andrea@suse.de>]

On Fri, Sep 03, 2004 at 02:12:21PM +0200, Kristian Sørensen wrote:
> Hi!
> 
> I have a short question, concerning how to get the full path of a file 
> from a LSM hook.
> 
> - If the "file" of the dentry is located in the root filesystem: no
>   problem - simply traverse the dentrys, to generate the path.
> 
> - If the "file" is mounted from another partition, you do not get the
>   full path by traversing the dentrys.
> 
> Example:
> If we have a system with a normal root (/) and a seperate boot partition 
> (mounted on /boot :). In the LSM hook inode_permission, you get the 
> arguments (struct inode *inode, int mask, struct nameidata *nd).
> Finding the path, we traverse the dentrys from (nd->dentry). But if the 
> inode is a file in /boot we only get the filename (e.g. kernel-2.6.8.1 
> instead of /boot/kernel-2.6.8.1)
> 
> 
> Can some one reveal the trick to get the full path nomater if the 
> filesystem is root or mounted elsewhere in the filesystem?

fix d_path, I need that too ;)