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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E9554C4332F for ; Tue, 20 Dec 2022 15:41:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230130AbiLTPlb (ORCPT ); Tue, 20 Dec 2022 10:41:31 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37860 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229810AbiLTPl3 (ORCPT ); Tue, 20 Dec 2022 10:41:29 -0500 Received: from mg.ssi.bg (mg.ssi.bg [193.238.174.37]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id F057110045; Tue, 20 Dec 2022 07:41:27 -0800 (PST) Received: from mg.ssi.bg (localhost [127.0.0.1]) by mg.ssi.bg (Proxmox) with ESMTP id 4DB3535200; Tue, 20 Dec 2022 17:41:27 +0200 (EET) Received: from ink.ssi.bg (unknown [193.238.174.40]) by mg.ssi.bg (Proxmox) with ESMTP id 6BCB435183; Tue, 20 Dec 2022 17:41:25 +0200 (EET) Received: from ja.ssi.bg (unknown [178.16.129.10]) by ink.ssi.bg (Postfix) with ESMTPS id C441F3C07CC; Tue, 20 Dec 2022 17:41:22 +0200 (EET) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by ja.ssi.bg (8.17.1/8.16.1) with ESMTP id 2BKFfKDx068357; Tue, 20 Dec 2022 17:41:20 +0200 Date: Tue, 20 Dec 2022 17:41:20 +0200 (EET) From: Julian Anastasov To: Paolo Abeni cc: Jon Maxwell , davem@davemloft.net, edumazet@google.com, kuba@kernel.org, yoshfuji@linux-ipv6.org, dsahern@kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [net-next] ipv6: fix routing cache overflow for raw sockets In-Reply-To: <9f145202ca6a59b48d4430ed26a7ab0fe4c5dfaf.camel@redhat.com> Message-ID: <98a8f9b6-36d1-d184-d860-e07a2e24fc9c@ssi.bg> References: <20221218234801.579114-1-jmaxwell37@gmail.com> <9f145202ca6a59b48d4430ed26a7ab0fe4c5dfaf.camel@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Hello, On Tue, 20 Dec 2022, Paolo Abeni wrote: > Are other FLOWI_FLAG_KNOWN_NH users affected, too? e.g. nf_dup_ipv6, > ipvs, seg6? I forgot to mention one thing: IPVS can cache such routes in its own storage, one per backend server, it still calls dst->ops->check for them. So, such route can live for long time, that is why they were created as uncached. So, IPVS requests one route, remembers it and then can attach it to multiple packets for this backend server with skb_dst_set_noref. So, IPVS have to use 4096 backend servers to hit this limit. It does not look correct in this patch to invalidate the FLOWI_FLAG_KNOWN_NH flag with a FLOWI_FLAG_SKIP_RAW flag. The same thing would be to not set FLOWI_FLAG_KNOWN_NH which is wrong for the hdrincl case. Regards -- Julian Anastasov