Re: kern/47040: renaming mount point panics in namei

[David Holland <dholland-bugs%netbsd.org@localhost>]

The following reply was made to PR kern/47040; it has been noted by GNATS.

From: David Holland <dholland-bugs%netbsd.org@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: 
Subject: Re: kern/47040: renaming mount point panics in namei
Date: Tue, 9 Oct 2012 15:19:56 +0000

 On Fri, Oct 05, 2012 at 02:00:08PM +0000, Taylor R Campbell wrote:
  >     I had a directory /foo/bar/current.ro, and I wanted to rename
  >     it to /foo/current.ro, so I ran
  > 
  >             % mv bar/current.ro .
  > 
  >     from /foo, forgetting that /foo/bar/current.ro had a file
  >     system mounted.  This immediately triggered a panic in namei:
  > 
  >             panic: leaf `current.ro' should be empty
  > 
  >     I am not sure which instance of the panic this is -- whether
  >     it's the one in lookup_once or the one in relookup -- because I
  >     can't read a kernel core dump on this machine.
 
 It doesn't matter, because either way it's caused by VOP_LOOKUP
 returning both an error and a result, which it's not supposed to do.
 
 Which fs(es)?
 
  >     (Real fix: rewrite namei...)
 
 Not this time! :-p
 
 -- 
 David A. Holland
 dholland%netbsd.org@localhost