>Number:         37626
>Category:       kern
>Synopsis:       puffs allows to mount a fs multiple times in the same mountpoint
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Dec 27 18:05:00 +0000 2007
>Originator:     juan@xtrarom.org
>Release:        NetBSD 4.99.45
>Organization:
Juan Romero Pardines	- The NetBSD Project
http://plog.xtrarom.org	- NetBSD/pkgsrc news in Spanish
>Environment:
System: NetBSD sasha 4.99.45 NetBSD 4.99.45 (Nocturno-nodbg) #127: Thu Dec 27 03:42:11 CET 2007 juan@sasha:/home/juan/build/i386/obj/sys/arch/i386/compile/Nocturno-nodbg i386
Architecture: i386
Machine: i386
>Description:

	Any PUFFS based file system (and refuse as well) allows to mount
	a file system in the same mount point multiple times, no other
	file system allows that AFAIK.

$ sudo mount -a
$ mount|grep puffs
/dev/puffs on /sysctl type puffs|sysctlfs
$ sudo mount -a    
$ mount|grep puffs 
/dev/puffs on /sysctl type puffs|sysctlfs
/dev/puffs on /sysctl type puffs|sysctlfs
$ sudo mount -a    
$ mount|grep puffs 
/dev/puffs on /sysctl type puffs|sysctlfs
/dev/puffs on /sysctl type puffs|sysctlfs
/dev/puffs on /sysctl type puffs|sysctlfs
$ sudo mount -a    
$ mount|grep puffs 
/dev/puffs on /sysctl type puffs|sysctlfs
/dev/puffs on /sysctl type puffs|sysctlfs
/dev/puffs on /sysctl type puffs|sysctlfs
/dev/puffs on /sysctl type puffs|sysctlfs
$

	The same happens with ntfs-3g, so perhaps is a general problem
	in PUFFS.

>How-To-Repeat:
>Fix:
	Yes, please.