From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: ppp/l2tp doing oversized allocations ? Date: Sat, 19 May 2012 08:25:30 +0200 Message-ID: <1337408730.7029.69.camel@edumazet-glaptop> References: <20120514162923.GA4439@redhat.com> <20120519.004652.2261671316587735315.davem@davemloft.net> <1337403685.7029.63.camel@edumazet-glaptop> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: davej@redhat.com, netdev@vger.kernel.org, kernel-team@fedoraproject.org, edumazet@google.com To: David Miller Return-path: Received: from mail-we0-f174.google.com ([74.125.82.174]:63366 "EHLO mail-we0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752763Ab2ESGZf (ORCPT ); Sat, 19 May 2012 02:25:35 -0400 Received: by weyu7 with SMTP id u7so2201637wey.19 for ; Fri, 18 May 2012 23:25:34 -0700 (PDT) In-Reply-To: <1337403685.7029.63.camel@edumazet-glaptop> Sender: netdev-owner@vger.kernel.org List-ID: On Sat, 2012-05-19 at 07:01 +0200, Eric Dumazet wrote: > On Sat, 2012-05-19 at 00:46 -0400, David Miller wrote: > > > So it's ESP encapsulated IPSEC over L2tp. > > > > Eric, I wonder if session->hdr_len can take on undesirable values and > > thus trip up the skb COW'ing calculations you added? > > I take a look, thanks > hdr_len is u16, I have no idea how we can reach MAX_ORDER page allocations... (more than 2 Mbytes...) Maybe a memory corruption, or a signed/unsigned mismatch.