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=-5.3 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 ECF88C433B4 for ; Mon, 17 May 2021 06:57:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C467A610C9 for ; Mon, 17 May 2021 06:57:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234544AbhEQG6e (ORCPT ); Mon, 17 May 2021 02:58:34 -0400 Received: from jabberwock.ucw.cz ([46.255.230.98]:49108 "EHLO jabberwock.ucw.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233732AbhEQG6e (ORCPT ); Mon, 17 May 2021 02:58:34 -0400 Received: by jabberwock.ucw.cz (Postfix, from userid 1017) id 27B081C0B79; Mon, 17 May 2021 08:57:17 +0200 (CEST) Date: Mon, 17 May 2021 08:57:16 +0200 From: Pavel Machek To: Paolo Abeni Cc: Pavel Machek , Greg Kroah-Hartman , linux-kernel@vger.kernel.org, stable@vger.kernel.org, Willem de Bruijn , "David S. Miller" , Sasha Levin Subject: Re: [PATCH 5.10 380/530] udp: never accept GSO_FRAGLIST packets Message-ID: <20210517065716.GA15967@amd> References: <20210512144819.664462530@linuxfoundation.org> <20210512144832.263718249@linuxfoundation.org> <20210515083717.GD30461@amd> <2e1ffc55aedb5d10eacce34cb7a5809138528d03.camel@redhat.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="5mCyUwZo2JvN/JJP" Content-Disposition: inline In-Reply-To: <2e1ffc55aedb5d10eacce34cb7a5809138528d03.camel@redhat.com> User-Agent: Mutt/1.5.23 (2014-03-12) Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org --5mCyUwZo2JvN/JJP Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hi! > > > From: Paolo Abeni > > >=20 > > > [ Upstream commit 78352f73dc5047f3f744764cc45912498c52f3c9 ] > > >=20 > > > Currently the UDP protocol delivers GSO_FRAGLIST packets to > > > the sockets without the expected segmentation. > > >=20 > > > This change addresses the issue introducing and maintaining > > > a couple of new fields to explicitly accept SKB_GSO_UDP_L4 > > > or GSO_FRAGLIST packets. Additionally updates udp_unexpected_gso() > > > accordingly. > > >=20 > > > UDP sockets enabling UDP_GRO stil keep accept_udp_fraglist > > > zeroed. > >=20 > > What is going on here? accept_udp_fraglist variable is read-only. >=20 > Thank you for checking this! >=20 > The 'accept_udp_fraglist' field is implicitly initilized to zero at UDP > socket allocation time (done by sk_alloc). >=20 > So this patch effectively force segmentation of SKB_GSO_FRAGLIST > packets via the udp_unexpected_gso() helper. >=20 > We introduce the above field instead of unconditionally > segmenting SKB_GSO_FRAGLIST, because the next patch will use it (to > avoid unneeded segmentation for performance's sake for UDP tunnel), as > you noted. Ok, but there's no follow up patch queued for 5.10...? Do we still need it there? Best regards, Pavel --=20 DENX Software Engineering GmbH, Managing Director: Wolfgang Denk HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany --5mCyUwZo2JvN/JJP Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iEYEARECAAYFAmCiE8wACgkQMOfwapXb+vKSSgCfeZuo7JR4uQEcDMFvMIhUOThF NHgAoKG9x+sITu6mXb4M4mLem5qKlaV3 =ws9+ -----END PGP SIGNATURE----- --5mCyUwZo2JvN/JJP--