From ywliu@rocketmail.com  Wed Dec  3 21:11:02 1997
Received: from web2.rocketmail.com (web2.rocketmail.com [205.180.57.68])
          by hub.freebsd.org (8.8.7/8.8.7) with SMTP id VAA20259
          for <FreeBSD-gnats-submit@freebsd.org>; Wed, 3 Dec 1997 21:11:02 -0800 (PST)
          (envelope-from ywliu@rocketmail.com)
Received: from [203.75.92.89] by web2; Wed, 03 Dec 1997 21:13:44 PST
Message-Id: <19971204051344.2328.rocketmail@web2.rocketmail.com>
Date: Wed, 3 Dec 1997 21:13:44 -0800 (PST)
From: Hoffmann Yen-Wei Liu <ywliu@rocketmail.com>
To: FreeBSD-gnats-submit@freebsd.org
Subject: nullfs crashes under several situations

>Number:         5212
>Category:       kern
>Synopsis:       nullfs crashes under several situations
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          closed
>Quarter:        
>Keywords:       
>Date-Required:  
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Wed Dec  3 21:20:01 PST 1997
>Closed-Date:    Sun Apr 19 13:03:57 PDT 1998
>Last-Modified:  Sun Apr 19 13:04:19 PDT 1998
>Originator:     Hoffmann Yen-Wei Liu
>Release:        FreeBSD 2.2.5-RELEASE i386
>Organization:
Sinanet.com, Inc.
>Environment:

AMD K6/200, 64MB RAM, PCI motherboard. FreeBSD 2.2.5 (both stock
and customized kernels).

>Description:

Some operations on nullfs would cause segmentation fault or kernel panic.

>How-To-Repeat:

1) when "tail"ing a file on nullfs, it usually gets seg fault, or kernel
   panic. (This happens both on 2.2.2 and 2.2.5, even with stock kernel.)

2) when nullfs is mounted, to remount it would cause kernel panic.
  (This happens, at least, on 2.2.5, even with stock kernel.)


>Fix:
	
1) I compiled a copy of "tail" from GNU textutil and it worked.

2) Avoid using "mount -a" when nullfs is mounted. Or avoid using nullfs.8-(


_________________________________________________________
DO YOU YAHOO!?
Get your free @yahoo.com address at http://mail.yahoo.com

>Release-Note:
>Audit-Trail:

From: Cy Schubert - BCSC Open Systems Group <cschuber@uumail.gov.bc.ca>
To: freebsd-gnats-submit@freebsd.org, ywliu@rocketmail.com
Cc: cy@passer.osg.gov.bc.ca
Subject: Re: kern/5212: nullfs crashes under several situations
Date: Wed, 17 Dec 1997 15:22:43 -0800

 I haven't had much chance to look at this (about 1/2 hour this morning),
 but my tests show that tyhe nullfs problems are caused by a divide by
 zero error at line 227 of vnode_pager.c (line 235 in the 2.2.2 version
 of this code).  My test was to ftp a file on a nullfs mounted filesystem
 on an (not anonymous) ftp server.
 
 f_iosize for nullfs, umapfs, and unionfs are set to zero so I can see
 this occuring for any of these filesystems.
 -- 
 Regards,                       Phone:  (250)387-8437
 Cy Schubert                      Fax:  (250)387-5766
 UNIX Support                   OV/VM:  BCSC02(CSCHUBER)
 ITSD                          BITNET:  CSCHUBER@BCSC02.BITNET
 Government of BC            Internet:  cschuber@uumail.gov.bc.ca
                                        Cy.Schubert@gems8.gov.bc.ca
 
 		"Quit spooling around, JES do it."
State-Changed-From-To: open->closed 
State-Changed-By: phk 
State-Changed-When: Sun Apr 19 13:03:57 PDT 1998 
State-Changed-Why:  
see PR 5355 
>Unformatted:
