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Date: Fri, 12 May 2017 00:35:21 -0700
From: Christoph Hellwig <hch@infradead.org>
To: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Ingo Molnar <mingo@kernel.org>, Andy Lutomirski <luto@kernel.org>,
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Subject: Re: [kernel-hardening] Re: [PATCH v9 1/4] syscalls: Verify address
 limit before returning to user-mode
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On Fri, May 12, 2017 at 08:15:49AM +0100, Al Viro wrote:
> And converting everything to ->read_iter()/->write_iter() means an insane
> amount of code churn, not to mention coping with random bogosities in
> semantics.  ->read() and ->write() are going to stay around, pretty
> much indefinitely.

But I don't think kernel users of them have to.  I've been digging
through the calllers and will send an analysis to the list in a bit.