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Subject: Re: [PATCH 2/2] proc,security: move restriction on writing
 /proc/pid/attr nodes to proc
From: =?ISO-8859-1?Q?Jos=E9?= Bollo <jobol@nonadev.net>
To: Casey Schaufler <casey@schaufler-ca.com>, John Johansen
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Date: Tue, 20 Dec 2016 15:40:41 +0100
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Le lundi 19 décembre 2016 à 13:25 -0800, Casey Schaufler a écrit :

snip
> 
> A brief look at the existing modules leads me to believe that
> everyone ought to be happier if we moved the LSM task blob out
> of the cred structure. SELinux keeps a small (6xu32) task blob
> that has no reason to share and refcount. Smack has a couple of
> lists in the task blob that really shouldn't be in the cred.
> There would have to be some rework of the task_alloc and task_free
> hooks to get the life of the blobs correct, but I think on the
> whole it would be lots cleaner.
> 

Hi Casey,

Let suppose that creds is, in effect, the wrong place for implementing
PTAGS and let suppose that the correct way is to add a t_ptags element
in the task structure.

How to use task_alloc and task_free? There is nothing there. Is it just
possible to inherit or copy the parent attributes? no.

So there is a need to define a hook to copy or do something for the
child based on the parent. A new hook, a kind of 'task_child_init'
whose argument would be the task to init.

Is it it?

Best regards
José Bollo