Subject: kern/767: another case of "panic: ufs_unlock NOT LOCKED"
To: None <gnats-admin@NetBSD.ORG>
From: None <firstname.lastname@example.org>
Date: 01/29/1995 19:05:11
>Synopsis: mounting via NFS over some process's cwd causes panic
>Responsible: kern-bug-people (Kernel Bug People)
>Arrival-Date: Sun Jan 29 19:05:08 1995
>Originator: Keith Moore
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
(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).
mount remote-host:/foo /some/directory
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.