Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262596AbVCVJoX (ORCPT ); Tue, 22 Mar 2005 04:44:23 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262598AbVCVJoX (ORCPT ); Tue, 22 Mar 2005 04:44:23 -0500 Received: from post.tau.ac.il ([132.66.16.11]:7096 "EHLO post.tau.ac.il") by vger.kernel.org with ESMTP id S262596AbVCVJoV (ORCPT ); Tue, 22 Mar 2005 04:44:21 -0500 Date: Tue, 22 Mar 2005 11:44:20 +0200 (IST) From: Hayim Shaul X-X-Sender: hayim@nova.cs.tau.ac.il To: Arjan van de Ven Cc: Gleb Natapov , linux-kernel@vger.kernel.org Subject: Re: mmap/munmap bug In-Reply-To: <1111480429.7096.47.camel@laptopd505.fenrus.org> Message-ID: References: <1111430042.6952.70.camel@laptopd505.fenrus.org> <20050322075658.GA32445@minantech.com> <1111478733.7096.36.camel@laptopd505.fenrus.org> <1111480429.7096.47.camel@laptopd505.fenrus.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 864 Lines: 21 >> >> What I thought of doing, is map the skbuff to user-space. Have the >> user-application alter the headers. Send the (same) skbuff from >> kernel-space. >> >> Does there exist anything equivalent? > > yes; netfilter has facilities for this actually afaik. > tcpdump also uses something like this (but only in one direction), it > mmaps some ringbuffer with incomming packets. Are you refering to NF_QUEUE + libipq ? I was under the impression that it does involve memcpy. Also, I think that with this you cannot change routing decisions made on the packet, although, I'm not sure yet how critical this is for me. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/