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Subject: Re: [PATCH] p9caps: add Plan9 capability devices
To:     "Serge E. Hallyn" <serge@hallyn.com>
Cc:     linux-kernel@vger.kernel.org
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 <20180211215028.16210-1-metux@gmx.de> <20180211215028.16210-2-metux@gmx.de>
 <20180213071655.GA11240@mail.hallyn.com>
From:   "Enrico Weigelt, metux IT consult" <metux@gmx.de>
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Date:   Tue, 13 Feb 2018 12:40:14 +0000
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On 13.02.2018 07:16, Serge E. Hallyn wrote:
>> +	/* make sure only one instance per namespace can be opened */ > > ... at a time
yeah, right.

> might be better to keep this state in the user_ns itself, would
> avoid kzalloc below.

thought about, but hesitated to touch user_ns. might not be the best
idea when having p9caps as module (OTOH, doesn't need to be a module)

the whole thing might become a bit more complex when introducing
plan9-like unprivileged mount operations. haven't sorted out how to
do that yet.

> Would it be worth doing any privilege checking here?

Which ones should I check ?


--mtx