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=-5.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 470FCC433DF for ; Wed, 26 Aug 2020 14:19:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 214562177B for ; Wed, 26 Aug 2020 14:19:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728094AbgHZOTe (ORCPT ); Wed, 26 Aug 2020 10:19:34 -0400 Received: from helcar.hmeau.com ([216.24.177.18]:33226 "EHLO fornost.hmeau.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728013AbgHZOTe (ORCPT ); Wed, 26 Aug 2020 10:19:34 -0400 Received: from gwarestrin.arnor.me.apana.org.au ([192.168.0.7]) by fornost.hmeau.com with smtp (Exim 4.92 #5 (Debian)) id 1kAwGa-00064P-1R; Thu, 27 Aug 2020 00:19:09 +1000 Received: by gwarestrin.arnor.me.apana.org.au (sSMTP sendmail emulation); Thu, 27 Aug 2020 00:19:08 +1000 Date: Thu, 27 Aug 2020 00:19:08 +1000 From: Herbert Xu To: Denis Kenzior Cc: Andrew Zaborowski , Ard Biesheuvel , Paul Menzel , Caleb Jorden , Sasha Levin , iwd@lists.01.org, "# 3.4.x" , Greg KH , LKML , "David S. Miller" , Linux Crypto Mailing List Subject: Re: Issue with iwd + Linux 5.8.3 + WPA Enterprise Message-ID: <20200826141907.GA5111@gondor.apana.org.au> References: <20200826055150.2753.90553@ml01.vlan13.01.org> <20200826114952.GA2375@gondor.apana.org.au> <20200826120832.GA2996@gondor.apana.org.au> <20200826130010.GA3232@gondor.apana.org.au> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-crypto-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org On Wed, Aug 26, 2020 at 08:57:17AM -0500, Denis Kenzior wrote: > > I'm just waking up now, so I might seem dense, but for my education, can you > tell me why we need to set MSG_MORE when we issue just a single sendmsg > followed immediately by recv/recvmsg? ell/iwd operates on small buffers, so > we don't really feed the kernel data in multiple send operations. You can > see this in the ell git tree link referenced in Andrew's reply. You obviously don't need MSG_MORE if you're doing a single sendmsg. The problematic code is in l_cipher_set_iv. It does a sendmsg(2) that expects to be followed by more sendmsg(2) calls before a recvmsg(2). That's the one that needs a MSG_MORE. Cheers, -- Email: Herbert Xu Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt