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Date: Mon, 29 Feb 2016 17:20:53 +0000
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Dmitry Vyukov <dvyukov@google.com>, Ian Kent <raven@themaw.net>,
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Subject: Re: fs: NULL deref in atime_needs_update
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On Mon, Feb 29, 2016 at 04:50:31PM +0000, Al Viro wrote:

> In __d_entry_type(), you mean?  Should be, along with READ_ONCE() there.
> AFAICS, ordering shouldn't be an issue anymore...

	FWIW, I've pushed the candidate fix (including the above) into
vfs.git#for-linus; I'd prefer to wait for confirmation that dcache.c
part is sufficient to fix the problem (_without_ reordering in lookup_fast())
before sending a pull request, though.