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Date: Sun, 13 May 2018 19:56:46 +0100
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        NeilBrown <neilb@suse.com>
Subject: Re: [RFC][PATCH] fix breakage caused by d_find_alias() semantics
 change
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On Sun, May 13, 2018 at 11:35:15AM -0700, Linus Torvalds wrote:
> On Sun, May 13, 2018 at 9:18 AM Al Viro <viro@zeniv.linux.org.uk> wrote:
> 
> >                          /* Called from selinux_complete_init, try to find
> a dentry. */
> >                          dentry = d_find_alias(inode);
> > +                       if (!dentry)
> > +                               dentry = d_find_any_alias(inode);
> 
> Can you please explain why this isn't just
> 
>          dentry = d_find_any_alias(inode);
> 
> without the initial "try to find a hashed alias"?

The whole reason why that thing is getting a dentry is that some filesystems
really want a *connected* dentry for getxattr.  Sure, saner ones will be
happy with disconnected dentry, but...

If you want to rearchitect the shitpile under security/* so that it would
not rely upon accidental properties of filesystems, you are welcome to that
and to the resulting psychiatrist bills ;-/