From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michael Tokarev Subject: Re: [Security, resend] Instant crash with rtl8169 and large packets Date: Mon, 08 Jun 2009 18:53:42 +0400 Message-ID: <4A2D25F6.9080300@msgid.tls.msk.ru> References: <4A2D1147.8020101@msgid.tls.msk.ru> <4A2D1FE4.5030100@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Linux-kernel , netdev To: Eric Dumazet Return-path: Received: from isrv.corpit.ru ([81.13.33.159]:37150 "EHLO isrv.corpit.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751731AbZFHOxm (ORCPT ); Mon, 8 Jun 2009 10:53:42 -0400 In-Reply-To: <4A2D1FE4.5030100@gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: Thank you Eric for the reply. Eric Dumazet wrote: > Michael Tokarev a =E9crit : [] >> The situation is very simple: with an RTL8169 (probably >> onboard) GigE card which, by default, is configured to >> have MTU (maximal transmission unit) to be 1500 bytes, >> it's *trivial* to instantly crash the machine by sending >> it a *single* packet of size >1500 bytes (provided the >> network switch can handle jumbo frames). [] >> http://www.corpit.ru/mjt/r8169-mtu-oops.jpg > I suppose you use a recent kernel ? http://marc.info/?t=3D123462473200002 -- here's my first attempt, at Feb this year. It was 2.6.27 or so. Right now I'm running 2.6.29[.4]. So I think yes, I use a recent kernel. > Could you please try following patch ? [] > diff --git a/drivers/net/r8169.c b/drivers/net/r8169.c > index e94316b..c08b97a 100644 > --- a/drivers/net/r8169.c > +++ b/drivers/net/r8169.c > @@ -3468,7 +3468,7 @@ static int rtl8169_rx_interrupt(struct net_devi= ce *dev, > =20 > if (status & DescOwn) > break; > - if (unlikely(status & RxRES)) { > + if (unlikely(status & (RxRES | RxRWT | RxRUNT | RxCRC | RxFOVF))) = { > if (netif_msg_rx_err(tp)) { > printk(KERN_INFO > "%s: Rx ERROR. status =3D %08x\n", Tried that one, got no printk (at least not a visible one) and exactly the same OOPS as before. Trivial test with ping -c1 -s3000 $my_ip_addr (learned to add -c1 because the previous time my machine crashed severa= l times in a row till I figured out what's going on and unplugged the ethernet = cord -- even if ping were running from an xterm executed from the machine to wh= ich I were pinging to! :) Also got ext4fs corruption when rebooted (it's a staging area so nothin= g important is there but still.. "interesting"). Also tried 32bit kernel (were using 64bits -- exactly the same result). I wish I had a serial cable or even a serial port on this machine.... B= ut I guess it'd not help anyway, because the machine locks hard. Thanks! /mjt