From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EB33CC3A5A1 for ; Thu, 22 Aug 2019 22:29:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9F976205ED for ; Thu, 22 Aug 2019 22:29:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731062AbfHVW3B (ORCPT ); Thu, 22 Aug 2019 18:29:01 -0400 Received: from shards.monkeyblade.net ([23.128.96.9]:49696 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726645AbfHVW3B (ORCPT ); Thu, 22 Aug 2019 18:29:01 -0400 Received: from localhost (unknown [IPv6:2601:601:9f80:35cd::d71]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id 7452815393F45; Thu, 22 Aug 2019 15:29:00 -0700 (PDT) Date: Thu, 22 Aug 2019 15:28:57 -0700 (PDT) Message-Id: <20190822.152857.1388207414767202364.davem@davemloft.net> To: casey@schaufler-ca.com Cc: fw@strlen.de, paul@paul-moore.com, netdev@vger.kernel.org, linux-security-module@vger.kernel.org, selinux@vger.kernel.org Subject: Re: New skb extension for use by LSMs (skb "security blob")? From: David Miller In-Reply-To: References: <32646e98-2ed6-a63a-5589-fefd57e85f66@schaufler-ca.com> <20190822.141845.217313560870249775.davem@davemloft.net> X-Mailer: Mew version 6.8 on Emacs 26.1 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-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Thu, 22 Aug 2019 15:29:00 -0700 (PDT) Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: From: Casey Schaufler Date: Thu, 22 Aug 2019 14:59:37 -0700 > Sure, you *can* do that, but it would be insane to do so. We look up the neighbour table entries on every single packet we transmit from the kernel in the same exact way. And it was exactly to get rid of a pointer in a data structure.