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

[Taylor R Campbell <campbell+netbsd%mumble.net@localhost>]

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

From: Taylor R Campbell <campbell+netbsd%mumble.net@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: kern-bug-people%netbsd.org@localhost, gnats-admin%netbsd.org@localhost,
        netbsd-bugs%netbsd.org@localhost
Subject: Re: kern/47040: renaming mount point panics in namei
Date: Tue, 9 Oct 2012 19:06:23 +0000

    Date: Tue, 9 Oct 2012 15:19:56 +0000
    From: David Holland <dholland-bugs%netbsd.org@localhost>
 
    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
 
    Which fs(es)?
 
 / is ffs sync, /foo is ffs async, and /foo/bar/current.ro is nullfs
 mounted read-only from /foo/bar/current, which is not a mount point.