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Date: Wed, 23 Mar 2016 10:19:47 +1100 (AEDT)
From: James Morris <jmorris@namei.org>
To: Seth Forshee <seth.forshee@canonical.com>
cc: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>,
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 Pavel Emelyanov <xemul@virtuozzo.com>
Subject: Re: [PATCH] fs: remove excess check for in_userns
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On Tue, 15 Mar 2016, Seth Forshee wrote:

> On Tue, Mar 15, 2016 at 03:09:00PM +0300, Pavel Tikhomirov wrote:
> > If in_userns returns false mnt_may_suid also returns false, and we
> > will reach second(removed) if-check only in case it does not trigger,
> > so remove it.
> 
> We had a somewhat lengthy discussion previously where one of the
> conclusions was that we'd have that check in both places even though
> it's redundant. Iirc the reason was that though they're doing the same
> test they're doing so to answer different questions, so we should have
> the test in both places (or something along those lines).

A comment in the code might be useful here.

-- 
James Morris
<jmorris@namei.org>