Subject: mount_union -> kernel panic
To: None <>
From: theo borm <>
List: tech-kern
Date: 06/07/2006 00:57:34
Dear list members,

using a stock 3.0 release generic kernel and sysctl -w 
any user can reliably cause a kernel panic by doing this:

mkdir over
mkdir under
mount_union over under
mount_union over under
ls under

I know that there doesn't seem to be much point in doing mount_union
twice (I did so by mistake), however I guess a kernel panic is a bit harsh
punishment for making a typo.

debugger says:
lockmgr: locking against myself
stopped in pid 1465.1 (ls) at netbsd.cpu_Debugger+0x4: leave

Does this sound familiar, anyone seen this before?
Can I help in any way to resolve this?

with kind regards,