From owner-freebsd-security Sun Apr 11 0: 6:20 1999 Delivered-To: freebsd-security@freebsd.org Received: from apollo.backplane.com (apollo.backplane.com [209.157.86.2]) by hub.freebsd.org (Postfix) with ESMTP id DE1E714F4A; Sun, 11 Apr 1999 00:06:14 -0700 (PDT) (envelope-from dillon@apollo.backplane.com) Received: (from dillon@localhost) by apollo.backplane.com (8.9.3/8.9.1) id AAA03493; Sun, 11 Apr 1999 00:03:49 -0700 (PDT) (envelope-from dillon) Date: Sun, 11 Apr 1999 00:03:49 -0700 (PDT) From: Matthew Dillon Message-Id: <199904110703.AAA03493@apollo.backplane.com> To: "David E. Cross" Cc: freebsd-hackers@FreeBSD.ORG, freebsd-security@FreeBSD.ORG Subject: Re: increased crashing in NFS server References: <199904110341.XAA17071@cs.rpi.edu> Sender: owner-freebsd-security@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org :I recently updated all of our FreeBSD3 clients to use NFSv3/UDP when :contacting our servers (FreeBSD3 of the same build tree). We have :noticed an increase in crashing of our main home directory server :(which is the only server really handling RW mounts, our other servers :are mostly RO, with some minor RW activity.) The first crash was :obviously NFS. I traced it to one of 2 possible crash points in the :kernel (sorry, no stack trace, we don't [yet] have a crashlogs enabled :for that machine.). : :The panic was: :mbuf siz=33476 :panic: Bad nfs svc reply You are using a 32K file block size? If so, reduce it to 8K. I think you've just shown us a security hole in the NFS system -- it panics if it is given too large a response packet. Oops. It should just print a message and drop the packet. :The second panic just happened, it claims to be softupdate related. I :think it may have something to do with NFSv3 however since this machine :used to be very stable (ie, not 2 crashes in a week). : :This panic was: :panic: softdep_write_inodeblock: indirect pointer #0 mismatch 0 != 102192 :8 :syncing disks... panic: softdep_lock: locking against myself :... : The Regents of the University of California. All rights reserved. :FreeBSD 3.1-STABLE #0: Sun Mar 21 02:23:19 EST 1999 : schimken@wobble.cs.rpi.edu:/usr/src/sys/compile/STAGGER :... :David Cross | WinNT:Linux::Linux:FreeBSD This is when you built it. When did you check the source out of the CVS tree? There have been a few commits in this area since Mar 21st, you definitely want to update your sources, but I don't think any of the commits address the above softupdates panic. I've never seen that panic before. I recommend fsck'ing all your filesystems from single-user just in case there's some garbage in there. -Matt Matthew Dillon To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-security" in the body of the message