From owner-freebsd-stable Sat Nov 2 3:47:14 2002 Delivered-To: freebsd-stable@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 5788E37B401 for ; Sat, 2 Nov 2002 03:47:12 -0800 (PST) Received: from scan.pnc.com.au (scan.pnc.com.au [203.13.174.123]) by mx1.FreeBSD.org (Postfix) with SMTP id 3889F43E3B for ; Sat, 2 Nov 2002 03:47:11 -0800 (PST) (envelope-from peterh@ripewithdecay.com) Received: (qmail 11772 invoked by uid 84); 2 Nov 2002 22:56:42 +1100 Received: from unknown (HELO dialup-204.159.220.203.acc01-high-pen.comindico.com.au) (203.13.174.1) by scan.pnc.com.au with SMTP; 2 Nov 2002 22:56:41 +1100 Date: Sat, 2 Nov 2002 22:47:08 +1100 (EST) From: Peter Hoskin X-X-Sender: peterh@extortion.peterh.dropbear.id.au To: "Jeroen C. van Gelderen" Cc: freebsd-stable@FreeBSD.ORG Subject: Re: rate-limiting uptime went backwards? In-Reply-To: <54AF0182-EE2C-11D6-AA9F-000393754B1C@vangelderen.org> Message-ID: <20021102224509.K301-100000@extortion.peterh.dropbear.id.au> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-stable@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Sat, 2 Nov 2002, Jeroen C. van Gelderen wrote: > > On Saturday, Nov 2, 2002, at 00:37 US/Eastern, Peter Hoskin wrote: > > > Those messages are usually due to a faulty system clock. Generally, > > when > > you generate a bit of load these messages will appear. The reason why > > they > > aren't rate limited is they are an important kernel message. > > Thanks for the explanation. > > What I do not understand still is how DoSing my machine with these > messages is going to be beneficial. It is bad enough that my clock is > not operating correctly so I can do without kernel log messages > grinding the machine to a halt. Its not a DoS attack. DoS attacks are a completely different thing, entirely. > My question stands: how is a message once a second going to be less > noticeable than a thousand per second? Usually you don't get as many messages. On the computers I've seen with a faulty system clock, one of these messages will appear every minute or so when the system is under high CPU usage or memory usage. Your system clock must be damaged badly. I recommend you replace your motherboard. > -J > > > > > Regards, > > Peter Hoskin > > > > On Fri, 1 Nov 2002, Jeroen C. van Gelderen wrote: > > > >> Hi, > >> > >> Is there any specific reason why the "microuptime went backwards" > >> message is not rate-limited? These messages are rather easy to provoke > >> by the local user tinkering with something as mundane as Java and > >> constitute a nice local DoS attack. > >> > >> -J > >> -- > >> Jeroen C. van Gelderen - jeroen@vangelderen.org - +1 242 357 5115 > >> Incentive Incompatibility > >> > >> > >> To Unsubscribe: send mail to majordomo@FreeBSD.org > >> with "unsubscribe freebsd-stable" in the body of the message > >> > > > > > -- > Jeroen C. van Gelderen - jeroen@vangelderen.org - +1 242 357 5115 > > "All that is necessary for evil to triumph is for good men to do > nothing." > -- Edmund Burke > > To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message