Subject: kern/3447: recent changes to specfs cause panics
To: None <gnats-bugs@gnats.netbsd.org>
From: Tom Yu <tlyu@mit.edu>
List: netbsd-bugs
Date: 04/03/1997 17:02:13
>Number: 3447
>Category: kern
>Synopsis: recent changes to specfs cause panics
>Confidential: no
>Severity: serious
>Priority: high
>Responsible: kern-bug-people (Kernel Bug People)
>State: open
>Class: sw-bug
>Submitter-Id: net
>Arrival-Date: Thu Apr 3 14:05:02 1997
>Last-Modified:
>Originator: Tom Yu
>Organization:
Kernel Hackers `R` Us
>Release: current (970402 sup)
>Environment:
System: NetBSD chaos-in-motion 1.2D NetBSD 1.2D (CHAOS) #4: Thu Apr 3 16:41:01 EST 1997 root@chaos-in-motion:/usr/pcmcia-src/sys/arch/i386/compile/CHAOS i386
>Description:
The addition of specfs_advlock() seems to corrupt some data
structures in such a way that calling exit() from a program can induce
a panic in lf_findoverlap(), which gets passed a bogus address
(0xdeadbeef) somehow from lf_clearlock().
>How-To-Repeat:
The specific case was running an Athena local version of CNS
kinit with a kernel compiled from the 970402 sup. Upon program exit,
the kernel panics.
>Fix:
The workaround is to remove the specfs_advlock() function. I
don't know what the real fix is, since I don't know too much about the
internal workings of lf_advlock(), and I don't really have time to
look into them at the moment.
>Audit-Trail:
>Unformatted: