From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ZenIV.linux.org.uk>
Subject: Re: /proc/pid/fd/ shows strange mode when executed via sudo.
Date: Fri, 18 May 2012 19:08:12 +0100
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> I would suggest just moving the i_mode initialization from
> proc_fd_instantiate() into the revalidate function that we already
> have, and that already fixes up i_uid/i_gid etc. Attached is a TOTALLY
> UNTESTED patch that does this, and actually seems to simplify things
> in the process.

I think this is bogus.  We don't give a fuck about *any* of those fields
for symlinks; the only problem here is that default ->getattr() uses
them to fill ->st_mode et.al.  The same goes for ->i_uid/->i_gid.
So how about simply adding ->getattr() for those guys?  And to hell
with assignments in that ->d_revalidate() instance...