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From: Kees Cook <keescook@chromium.org>
To: yunhui cui <cuiyunhui@bytedance.com>, brauner@kernel.org
Cc: jeffxu@google.com, akpm@linux-foundation.org, cyphar@cyphar.come,
	mcgrof@kernel.org, frederic@kernel.org,
	lkml - Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: Discuss the implementation of pidns_install()
Date: Mon, 9 Oct 2023 13:08:05 -0700	[thread overview]
Message-ID: <202310091307.CB416B950@keescook> (raw)
In-Reply-To: <CAEEQ3wnfOOpKAKGt07cFv1Du-NaFOzX_=yeQZfD6VNojpPFTqA@mail.gmail.com>

On Wed, Sep 20, 2023 at 05:37:20PM +0800, yunhui cui wrote:
> Hi Kees, jeff, Andrew, Christian,
> 
> We hope that containers at the same level can also switch pid namespace.
> To fork() the entire pstree of a container, we need to switch from the pid
> namespace of the template container to the  target container's pid
> namespace. But it is blocked by the following code:
> 
> ...
>         while (ancestor->level > active->level)
>                 ancestor = ancestor->parent;
>         if (ancestor != active)
>                 return -EINVAL;
> ...
> 
> Can we give this code permission, such as CAP_SYS_ADMIN ..., so that those
> with this permission can switch to sibling pid namespace. Rather than just
> parent, parent ...
> 
> Do you think this plan is okay?  Or can you give me some suggestions?

I'll defer to Christian on this, but it seems like moving processes
sideways is kind of unexpected. I agree it'd need privilege if we did
it, though.

-- 
Kees Cook

       reply	other threads:[~2023-10-09 20:08 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <CAEEQ3wnfOOpKAKGt07cFv1Du-NaFOzX_=yeQZfD6VNojpPFTqA@mail.gmail.com>
2023-10-09 20:08 ` Kees Cook [this message]
2023-10-10  3:29   ` [External] Re: Discuss the implementation of pidns_install() yunhui cui
2023-10-11  1:46     ` yunhui cui

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