From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752892Ab2DCCAX (ORCPT ); Mon, 2 Apr 2012 22:00:23 -0400 Received: from shards.monkeyblade.net ([198.137.202.13]:57149 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752374Ab2DCCAW (ORCPT ); Mon, 2 Apr 2012 22:00:22 -0400 Date: Mon, 02 Apr 2012 21:59:11 -0400 (EDT) Message-Id: <20120402.215911.1929019308299701014.davem@davemloft.net> To: eric.dumazet@gmail.com Cc: remi@remlab.net, levinsasha928@gmail.com, remi.denis-courmont@nokia.com, davej@redhat.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] phonet: Check input from user before allocating From: David Miller In-Reply-To: <1333417997.18626.1.camel@edumazet-glaptop> References: <201204022201.41808.remi@remlab.net> <20120402.174006.70116829696492189.davem@davemloft.net> <1333417997.18626.1.camel@edumazet-glaptop> X-Mailer: Mew version 6.4 on Emacs 23.3 / Mule 6.0 (HANACHIRUSATO) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.2.6 (shards.monkeyblade.net [198.137.202.13]); Mon, 02 Apr 2012 18:59:13 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Eric Dumazet Date: Tue, 03 Apr 2012 03:53:17 +0200 > Not that AF_UNIX does nothing in this respect, it can use order-XX pages > for large datagrams. > > (I beleve I sent a patch some time ago to address this point) Yes, on the datagram side it's a problem. For stream AF_UNIX sockets the allocation is capped at SKB_MAX_ALLOC which evaluates to an order 2 page. Overall, AF_UNIX ought to be easy to deal with since all of the routines that copy data between userspace and SKBs can handle segmented SKBs and thus most of the work is converting over to sock_alloc_send_pskb() and setting data_len how we set the normal length of sock_alloc_skb_skb() currently. Anyways, feel free to resubmit your patch.