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=-10.6 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_PASS,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable 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 A39D6C10F03 for ; Fri, 22 Mar 2019 19:59:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6D30F218FE for ; Fri, 22 Mar 2019 19:59:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="EdhJmICG" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726087AbfCVT7I (ORCPT ); Fri, 22 Mar 2019 15:59:08 -0400 Received: from mail-vk1-f201.google.com ([209.85.221.201]:46765 "EHLO mail-vk1-f201.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725999AbfCVT7H (ORCPT ); Fri, 22 Mar 2019 15:59:07 -0400 Received: by mail-vk1-f201.google.com with SMTP id v82so1252524vkd.13 for ; Fri, 22 Mar 2019 12:59:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:message-id:mime-version:subject:from:to:cc; bh=zShM0RWqFlfrPUijnY1kNbwqoHuA2eXHgjycKhDvh0s=; b=EdhJmICGrjMjQ74HOZdU1XqWykhqpWpKp5yiVOqHvYR9p7sxSmsKvqksqcxvjnqTFZ f4VGTHkvfz+4l+0fIuetYkmNr9WMeF8lcP52QSoAGzhvyaJlTTV3iH+AF2tLtSM5zBhn YrFsfXACQ0SYRZ8RMhnsLnXDPhyqQ3bijUGCv1inSigLOUBlSQziHLCF2zg+6L2TKioQ abiltjF3FSacklfqYswbBlGiEdNTHjy98uXw2EdaoiJlUHkWFld8kwdelZcH4TjS35JE BOxqdTTmzzbQJ28YwPObLorYyAgzrhyz7wDlEZRMWjst507ZJBpxXJ8whZSPPD9aKzHL WbMQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:message-id:mime-version:subject:from:to:cc; bh=zShM0RWqFlfrPUijnY1kNbwqoHuA2eXHgjycKhDvh0s=; b=KjQv0IikjCfBio/OShoHgwtScKm7Yypj294VVFtzsvIahqwBQOxJSCdAVh1GqViZwP SL/c2cpQa/GvKsbrh6C0XEiMmbujj47SUAje8+gXE4AqAWKjUYHiFAwhGB9lEdqnVJYH iR7t0BLJldNset+ZcDiB+lZtng5UAGuUaCDBeEfsoJpLGaLyg1Axy77YDuGLZnB9QM+t D10knf0faSF96Vc27EMhFlTQiTQHhHNADPNDXxGM8nEjdGB+uYDYKLflcxsIuIL8GH1/ oIvjzAo/4xqdOXuEPwXiOUAo49QiMKRyNMeRizWT5Zh7WjyVhZfUZrcRZYvyDurKlfkL khFg== X-Gm-Message-State: APjAAAVdx1i0GDEMrs5SGUxSv8siZfEGeoE9kJRx1UOoYR6ip3uxaBE5 h4WBvsvoEqmfNPW6UTkgVms350UGHCOEMdnZWb+r8akmGJk42KFudNMJjUPBzfp5XLjFL286WZ+ KwYuj4IQ2GdosWciwSH4IJ+qMkMMiSU0SlLh9phZfW1Enn6TI6Xc9rA== X-Google-Smtp-Source: APXvYqwbT9vrnxL2qVpxaMcdS099gbZ3tMbbtGfnBSLK/UmqNuZQdi34IscES//P7lsIcVelgeWF9qs= X-Received: by 2002:a1f:1282:: with SMTP id 124mr7119344vks.45.1553284746270; Fri, 22 Mar 2019 12:59:06 -0700 (PDT) Date: Fri, 22 Mar 2019 12:58:55 -0700 Message-Id: <20190322195903.162516-1-sdf@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.21.0.392.gf8f6787159e-goog Subject: [RFC bpf-next v3 0/8] net: flow_dissector: trigger BPF hook when called from eth_get_headlen From: Stanislav Fomichev To: netdev@vger.kernel.org, bpf@vger.kernel.org Cc: davem@davemloft.net, ast@kernel.org, daniel@iogearbox.net, simon.horman@netronome.com, willemb@google.com, peterpenkov96@gmail.com, Stanislav Fomichev Content-Type: text/plain; charset="UTF-8" Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Currently, when eth_get_headlen calls flow dissector, it doesn't pass any skb. Because we use passed skb to lookup associated networking namespace to find whether we have a BPF program attached or not, we always use C-based flow dissector in this case. The goal of this patch series is to add new networking namespace argument to the eth_get_headlen and make BPF flow dissector programs be able to work in the skb-less case. The series goes like this: 1. restrict access to a limited set of __sk_buff fields from flow dissector programs; in eth_get_headlen context, they don't make sense (for skb-context, they are also not relevant for flow dissector) 2. switch kernel context to new xdp_buff-like structure (struct bpf_flow_dissector) for flow dissector program 3. minor fix for nhoff clamping; doesn't affect anything besides tests 4. convert flow dissector BPF_PROG_TEST_RUN to skb-less mode to show that it works 5. add new optional network namespace argument to __skb_flow_dissect and plumb through the callers 6. handle __skb_flow_dissect with skb == NULL 7. add new net namespace argument to eth_get_headlen and adjust all users 8. add selftest that makes sure bpf_skb_load_bytes is prohibited in skb-less context v3: * new kernel xdp_buff-like context per Alexey suggestion * drop skb_net helper * properly clamp flow_keys->nhoff v2: * moved temporary skb from stack into percpu (avoids memset of ~200 bytes per packet) * tightened down access to __sk_buff fields from flow dissector programs to avoid touching shinfo (whitelist only relevant fields) * addressed suggestions from Willem Stanislav Fomichev (8): flow_dissector: allow access only to a subset of __sk_buff fields flow_dissector: switch kernel context to struct bpf_flow_dissector flow_dissector: fix clamping of BPF flow_keys for non-zero nhoff bpf: when doing BPF_PROG_TEST_RUN for flow dissector use no-skb mode net: plumb network namespace into __skb_flow_dissect flow_dissector: handle no-skb use case net: pass net argument to the eth_get_headlen selftests/bpf: add flow dissector bpf_skb_load_bytes helper test drivers/net/ethernet/broadcom/bnxt/bnxt.c | 2 +- drivers/net/ethernet/hisilicon/hns/hns_enet.c | 3 +- .../net/ethernet/hisilicon/hns3/hns3_enet.c | 3 +- drivers/net/ethernet/intel/fm10k/fm10k_main.c | 2 +- drivers/net/ethernet/intel/i40e/i40e_txrx.c | 3 +- drivers/net/ethernet/intel/iavf/iavf_txrx.c | 3 +- drivers/net/ethernet/intel/ice/ice_txrx.c | 2 +- drivers/net/ethernet/intel/igb/igb_main.c | 3 +- drivers/net/ethernet/intel/igc/igc_main.c | 3 +- drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 2 +- .../net/ethernet/intel/ixgbevf/ixgbevf_main.c | 3 +- .../net/ethernet/mellanox/mlx5/core/en_tx.c | 3 +- drivers/net/tun.c | 3 +- include/linux/etherdevice.h | 2 +- include/linux/skbuff.h | 23 ++- include/net/flow_dissector.h | 11 ++ include/net/sch_generic.h | 11 +- net/bpf/test_run.c | 51 ++---- net/core/filter.c | 151 +++++++++++++----- net/core/flow_dissector.c | 85 +++++----- net/ethernet/eth.c | 8 +- .../prog_tests/flow_dissector_load_bytes.c | 48 ++++++ 22 files changed, 280 insertions(+), 145 deletions(-) create mode 100644 tools/testing/selftests/bpf/prog_tests/flow_dissector_load_bytes.c -- 2.21.0.392.gf8f6787159e-goog