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Date: Sun, 26 Apr 2020 16:59:58 +0100
From: Al Viro <viro@zeniv.linux.org.uk>
To: Christoph Hellwig <hch@lst.de>
Cc: Kees Cook <keescook@chromium.org>, Iurii Zaikin <yzaikin@google.com>,
	Alexei Starovoitov <ast@kernel.org>,
	Daniel Borkmann <daniel@iogearbox.net>,
	linux-kernel@vger.kernel.org, linux-mm@kvack.org,
	linux-fsdevel@vger.kernel.org, netdev@vger.kernel.org,
	bpf@vger.kernel.org
Subject: Re: pass kernel pointers to the sysctl ->proc_handler method v3
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References: <20200424064338.538313-1-hch@lst.de>
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On Fri, Apr 24, 2020 at 08:43:33AM +0200, Christoph Hellwig wrote:
> Hi all,
> 
> this series changes the sysctl ->proc_handler methods to take kernel
> pointers.  This simplifies some of the pointer handling in the methods
> (which could probably be further simplified now), and gets rid of the
> set_fs address space overrides used by bpf.
> 
> Changes since v2:
>  - free the buffer modified by BPF
>  - move pid_max and friends to pid.h
> 
> Changes since v1:
>  - drop a patch merged by Greg
>  - don't copy data out on a write
>  - fix buffer allocation in bpf

OK, I can live with that; further work can live on top of that, anyway.
How are we going to handle that?  I can put it into never-rebased branch
in vfs.git (#work.sysctl), so that people could pull that.

FWIW, I'm putting together more uaccess stuff (will probably hit -next
tonight or tomorrow); this would fit well there...