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Re: NSA SE enabled devfsd

To: SE Linux <selinux@xxxxxxxxxxxxx>
Subject: Re: NSA SE enabled devfsd
From: Russell Coker <russell@xxxxxxxxxxxx>
Date: Wed, 6 Mar 2002 13:16:38 +0100
Cc: devfs@xxxxxxxxxxx
Reply-to: Russell Coker <russell@xxxxxxxxxxxx>
Sender: owner-devfs@xxxxxxxxxxx
On Wed, 6 Mar 2002 00:23, Russell Coker wrote:
> I have hacked support for SE Linux into devfsd.

I have found one problem with my current code.  devfsd wants to re-apply it's 
permissions to device nodes whenever it's restarted and whenever you do
"killall -1 devfsd"  to tell it to reload it's config.

During the course of a login session the SID of the pty device will change.  
It starts as devpts_t, goes to sshd_devpts_t (for a ssh session - an 
equivalent type for a non-ssh session), then goes to user_t (or an 
appropriate type for the user).

So if devfsd is restarted when someone is logged in then the result is likely 
to be a logout for them (which is tough if you've logged in to change the 
devfsd config).

Currently I've got my devfsd config matching on ^pts$ and using domain 
transition rules for the rest.

For the /dev/vc/* devices (devfs equivalent to /dev/tty[0-9]*) the only 
solution I get think of right now is to have the devfs_contexts file specify 
them.



Also this is not an issue that is restricted to SE Linux.  Currently if I run 
"killall -1 devfsd" it will be equivalent to "mesg n" for all users!

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