Subject: kern/767: another case of "panic: ufs_unlock NOT LOCKED"
To: None <gnats-admin@NetBSD.ORG>
From: None <moore@cs.utk.edu>
List: netbsd-bugs
Date: 01/29/1995 19:05:11
>Number:         767
>Category:       kern
>Synopsis:       mounting via NFS over some process's cwd causes panic
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people (Kernel Bug People)
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Jan 29 19:05:08 1995
>Originator:     Keith Moore
>Organization:
"none"
>Release:        1.0
>Environment:
sparcstation1, netbsd-1.0

System: NetBSD lust.cs.utk.edu 1.0 NetBSD 1.0 (SPARC_SCSI3) #0: Mon Oct 24 15:23:27 MDT 1994 deraadt@croc:/croc.usera/rel/src/sys/arch/sparc/compile/SPARC_SCSI3 sparc


>Description:
	(this appears to be the same bug as kern/498...this is just
	another data point)
	if you mount a remote NFS filesystem over someone's current
	directory, the kernel will panic when that person tries to
	access that directory (underneath the mount).

>How-To-Repeat:
	cd /some/directory
	mount remote-host:/foo /some/directory
	ls

>Fix:
	On the UNIX systems I'm used to, this could not happen because mount
	(2) would return EBUSY.  My guess is that this is really a problem 
	with mount() not doing enough checking for this case.
>Audit-Trail:
>Unformatted: