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From: Eric Paris <eparis@redhat.com>
To: "J. R. Okajima" <hooanon05@yahoo.co.jp>
Cc: James Morris <jmorris@namei.org>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	linux-kernel@vger.kernel.org,
	linux-security-module@vger.kernel.org, w41ter@gmail.com
Subject: Re: [GIT] Security updates for 3.3: SELinux
Date: Tue, 17 Jan 2012 09:38:42 -0500	[thread overview]
Message-ID: <1326811122.2937.4.camel@localhost> (raw)
In-Reply-To: <12887.1326810483@jrobl>

On Tue, 2012-01-17 at 23:28 +0900, J. R. Okajima wrote:
> James Morris:
> > Eric Paris (12):
> 	:::
> >       capabitlies: ns_capable can use the cap helpers rather than lsm call
> 
> After this commit, I am afraid access(2) on NFS may not work correctly.
> The scenario based upon my guess.
> - access(2) overrides the credentials.
> - calls inode_permission() -- ... -- generic_permission() --
>   ns_capable().
> - while the old ns_capable() calls security_capable(current_cred()), the
>   new ns_capable() calls has_ns_capability(current) --
>   security_capable(__task_cred(t)).
> 
> current_cred() returns current->cred which is effective (overridden)
> credentials, but __task_cred(current) returns current->real_cred (the
> NFSD's credential). And the overridden credentials by access(2) lost.
> 
> Is my guess correct?

Linus please revert d2a7009f0bb03fa22ad08dd25472efa0568126b9

Your explanation seems plausible.  I will review the rest and make sure
a similar problem was not introduced elsewhere.

-Eric


      reply	other threads:[~2012-01-17 14:38 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-01-15  2:25 [GIT] Security updates for 3.3: SELinux James Morris
2012-01-15  2:54 ` Linus Torvalds
2012-01-15  4:04   ` James Morris
2012-01-17 14:28 ` J. R. Okajima
2012-01-17 14:38   ` Eric Paris [this message]

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