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Date: Sun, 4 Sep 2016 15:29:39 +0100
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Dmitry Vyukov <dvyukov@google.com>
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Subject: Re: fs: GPF in bd_mount
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On Sun, Sep 04, 2016 at 03:06:06PM +0100, Al Viro wrote:

> Said that, I'm not sure why mount_pseudo() would be returning any errors;
> rejection should happen in the caller (due to MS_NOUSER in the flags), but
> I don't understand what would trigger it on mount_pseudo() level...

I see what's going on, but I wonder if sget() is the right place for userns
checks...