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=-3.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS autolearn=ham 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 B78A7C43613 for ; Mon, 24 Jun 2019 16:41:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8B9F520665 for ; Mon, 24 Jun 2019 16:41:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="VJVRjzpU" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729839AbfFXQlp (ORCPT ); Mon, 24 Jun 2019 12:41:45 -0400 Received: from mail-pl1-f194.google.com ([209.85.214.194]:36138 "EHLO mail-pl1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726700AbfFXQlp (ORCPT ); Mon, 24 Jun 2019 12:41:45 -0400 Received: by mail-pl1-f194.google.com with SMTP id k8so7220942plt.3 for ; Mon, 24 Jun 2019 09:41:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=gm5sBRa22v+IZDsSpfzTxb4F4fV04kTMGW118ImiSvI=; b=VJVRjzpUp59zJFTXonFi0Ga39oxdoKoZcoWQ63TheN3nBIohri3p8Yi8XKb+lC8nIk sKd4eJYpw0aKx16TGjnBPBS3zVlrNkVPsAvyyR6A0i/osYoXbkBZS+6yyB3FUOuj7HWL cN7xCpK0nujho3ZX+tceDBOo7cXZjiRHs2X330w4GIHY2bMItWmD80j4RsP09P8gpvpm PgZvYaEA0J2p1YU54m9Frq/hbMhPZaU1vHTbqGILLfe7OuK+E7iVGkOztwh9CamBBhg0 6JeougBEkrWcUNT2R3zqijLFeN75RTy/68RM6+0aK3TGffIEqe382fPqqhg5hgHttDuf 2rUw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=gm5sBRa22v+IZDsSpfzTxb4F4fV04kTMGW118ImiSvI=; b=BTiLsvzk35nT/kyALQ86oym59tI7dI1w80VzIBpbejx8ed1JJGtxcL0fAYmZPEPh13 LowN3Hmp3ccMWQkZUqCPQV87xVFLIJs5tFlt+kWYJafja/AkqBnLSezf6P5NyMBCwQnY boueBx4i+vU7eGZpK56IkraAS3n2EYB8Rg+ibpK+Wdz7uETec2vIHVyOZ68NSTkAV0hh RJHz1i39U3/Hx/DDdSYJOJ1JSGFIOmwrqw7Wh3J1V9pYfuPjE7v9pttITexYlT7OqLNO Twh6Xg4nnbd5syAoy6O8BGI7I6ze4tFTx/c03o21zwIi+lVWj3u8dVYnzK+P7m/+PIva eyqw== X-Gm-Message-State: APjAAAVgqVyKQgJx52KymOQnT5Mks4kLP49l8VNFo5DBSn857AsKJGlm 13YWgNCdoT+E0jv4YAcwFxk= X-Google-Smtp-Source: APXvYqycbKl+WU2Z4fCNKrDPrP1xJPgMx8fbrKlgd0OxgXqJ6yG64tM1nFlcXMZ5XheC+eDJiMZFQg== X-Received: by 2002:a17:902:1003:: with SMTP id b3mr150966269pla.172.1561394504912; Mon, 24 Jun 2019 09:41:44 -0700 (PDT) Received: from [172.20.181.193] ([2620:10d:c090:180::1:73aa]) by smtp.gmail.com with ESMTPSA id l68sm25029pjb.8.2019.06.24.09.41.44 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 24 Jun 2019 09:41:44 -0700 (PDT) From: "Jonathan Lemon" To: "Toke =?utf-8?b?SMO4aWxhbmQtSsO4cmdlbnNlbg==?=" Cc: netdev@vger.kernel.org, "Jesper Dangaard Brouer" , "Daniel Borkmann" , "Alexei Starovoitov" , "David Miller" Subject: Re: [PATCH bpf-next v5 3/3] devmap: Allow map lookups from eBPF Date: Mon, 24 Jun 2019 09:41:43 -0700 X-Mailer: MailMate (1.12.5r5635) Message-ID: <66A081F4-544F-4AA7-9412-D18AE5670F71@gmail.com> In-Reply-To: <156125626158.5209.14261186257358121509.stgit@alrua-x1> References: <156125626076.5209.13424524054109901554.stgit@alrua-x1> <156125626158.5209.14261186257358121509.stgit@alrua-x1> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 22 Jun 2019, at 19:17, Toke Høiland-Jørgensen wrote: > From: Toke Høiland-Jørgensen > > We don't currently allow lookups into a devmap from eBPF, because the map > lookup returns a pointer directly to the dev->ifindex, which shouldn't be > modifiable from eBPF. > > However, being able to do lookups in devmaps is useful to know (e.g.) > whether forwarding to a specific interface is enabled. Currently, programs > work around this by keeping a shadow map of another type which indicates > whether a map index is valid. > > Since we now have a flag to make maps read-only from the eBPF side, we can > simply lift the lookup restriction if we make sure this flag is always set. > > Signed-off-by: Toke Høiland-Jørgensen Acked-by: Jonathan Lemon