From patchwork Sun Aug 2 21:36:31 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Yakunin X-Patchwork-Id: 262817 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=-10.1 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, 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 24211C433DF for ; Sun, 2 Aug 2020 21:36:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0B9BF20738 for ; Sun, 2 Aug 2020 21:36:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=yandex-team.ru header.i=@yandex-team.ru header.b="mDlZvrqf" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727996AbgHBVgi (ORCPT ); Sun, 2 Aug 2020 17:36:38 -0400 Received: from forwardcorp1j.mail.yandex.net ([5.45.199.163]:45172 "EHLO forwardcorp1j.mail.yandex.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727979AbgHBVgh (ORCPT ); Sun, 2 Aug 2020 17:36:37 -0400 Received: from vla1-fdfb804fb3f3.qloud-c.yandex.net (vla1-fdfb804fb3f3.qloud-c.yandex.net [IPv6:2a02:6b8:c0d:3199:0:640:fdfb:804f]) by forwardcorp1j.mail.yandex.net (Yandex) with ESMTP id 49FA72E0B02; Mon, 3 Aug 2020 00:36:34 +0300 (MSK) Received: from vla5-58875c36c028.qloud-c.yandex.net (vla5-58875c36c028.qloud-c.yandex.net [2a02:6b8:c18:340b:0:640:5887:5c36]) by vla1-fdfb804fb3f3.qloud-c.yandex.net (mxbackcorp/Yandex) with ESMTP id iSzER396Iw-aYqibU7n; Mon, 03 Aug 2020 00:36:34 +0300 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yandex-team.ru; s=default; t=1596404194; bh=0+K6ekHFGCKpywJPU+f+Df3pWthE/8ooVEOmlxubSu0=; h=In-Reply-To:Message-Id:References:Date:Subject:To:From:Cc; b=mDlZvrqfW3zeKLH99/WqKp2EFY0MwjiTA2UDtOnb96TnO9JW5Lts0G9IwRKS8IMat lhybist38D52rvPyThha+4FvRRXcSpzAtSYMIyWepnpDZ9OiTOSRc2uoiLKcAHfWNQ /+m5T5/5zy7BcMTt65dZBkMsaiiF96kmg0ftJcb0= Authentication-Results: vla1-fdfb804fb3f3.qloud-c.yandex.net; dkim=pass header.i=@yandex-team.ru Received: from unknown (unknown [178.154.141.161]) by vla5-58875c36c028.qloud-c.yandex.net (smtpcorp/Yandex) with ESMTPSA id PUeY1PJp81-aXji7CVd; Mon, 03 Aug 2020 00:36:34 +0300 (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client certificate not present) From: Dmitry Yakunin To: alexei.starovoitov@gmail.com, daniel@iogearbox.net, netdev@vger.kernel.org, bpf@vger.kernel.org Cc: sdf@google.com Subject: [PATCH bpf-next v5 2/2] bpf: allow to specify ifindex for skb in bpf_prog_test_run_skb Date: Mon, 3 Aug 2020 00:36:31 +0300 Message-Id: <20200802213631.78937-3-zeil@yandex-team.ru> In-Reply-To: <20200802213631.78937-1-zeil@yandex-team.ru> References: <20200802213631.78937-1-zeil@yandex-team.ru> MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Now skb->dev is unconditionally set to the loopback device in current net namespace. But if we want to test bpf program which contains code branch based on ifindex condition (eg filters out localhost packets) it is useful to allow specifying of ifindex from userspace. This patch adds such option through ctx_in (__sk_buff) parameter. Signed-off-by: Dmitry Yakunin --- net/bpf/test_run.c | 22 ++++++++++++++++++++-- tools/testing/selftests/bpf/prog_tests/skb_ctx.c | 5 +++++ 2 files changed, 25 insertions(+), 2 deletions(-) diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c index 8d69295..369ce90 100644 --- a/net/bpf/test_run.c +++ b/net/bpf/test_run.c @@ -327,6 +327,12 @@ static int convert___skb_to_skb(struct sk_buff *skb, struct __sk_buff *__skb) /* priority is allowed */ if (!range_is_zero(__skb, offsetofend(struct __sk_buff, priority), + offsetof(struct __sk_buff, ifindex))) + return -EINVAL; + + /* ifindex is allowed */ + + if (!range_is_zero(__skb, offsetofend(struct __sk_buff, ifindex), offsetof(struct __sk_buff, cb))) return -EINVAL; @@ -381,6 +387,7 @@ static void convert_skb_to___skb(struct sk_buff *skb, struct __sk_buff *__skb) __skb->mark = skb->mark; __skb->priority = skb->priority; + __skb->ifindex = skb->dev->ifindex; __skb->tstamp = skb->tstamp; memcpy(__skb->cb, &cb->data, QDISC_CB_PRIV_LEN); __skb->wire_len = cb->pkt_len; @@ -391,6 +398,8 @@ int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr, union bpf_attr __user *uattr) { bool is_l2 = false, is_direct_pkt_access = false; + struct net *net = current->nsproxy->net_ns; + struct net_device *dev = net->loopback_dev; u32 size = kattr->test.data_size_in; u32 repeat = kattr->test.repeat; struct __sk_buff *ctx = NULL; @@ -432,7 +441,7 @@ int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr, kfree(ctx); return -ENOMEM; } - sock_net_set(sk, current->nsproxy->net_ns); + sock_net_set(sk, net); sock_init_data(NULL, sk); skb = build_skb(data, 0); @@ -446,7 +455,14 @@ int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr, skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN); __skb_put(skb, size); - skb->protocol = eth_type_trans(skb, current->nsproxy->net_ns->loopback_dev); + if (ctx && ctx->ifindex > 1) { + dev = dev_get_by_index(net, ctx->ifindex); + if (!dev) { + ret = -ENODEV; + goto out; + } + } + skb->protocol = eth_type_trans(skb, dev); skb_reset_network_header(skb); switch (skb->protocol) { @@ -502,6 +518,8 @@ int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr, ret = bpf_ctx_finish(kattr, uattr, ctx, sizeof(struct __sk_buff)); out: + if (dev && dev != net->loopback_dev) + dev_put(dev); kfree_skb(skb); bpf_sk_storage_free(sk); kfree(sk); diff --git a/tools/testing/selftests/bpf/prog_tests/skb_ctx.c b/tools/testing/selftests/bpf/prog_tests/skb_ctx.c index 7021b92..25de86a 100644 --- a/tools/testing/selftests/bpf/prog_tests/skb_ctx.c +++ b/tools/testing/selftests/bpf/prog_tests/skb_ctx.c @@ -11,6 +11,7 @@ void test_skb_ctx(void) .cb[3] = 4, .cb[4] = 5, .priority = 6, + .ifindex = 1, .tstamp = 7, .wire_len = 100, .gso_segs = 8, @@ -92,6 +93,10 @@ void test_skb_ctx(void) "ctx_out_priority", "skb->priority == %d, expected %d\n", skb.priority, 7); + CHECK_ATTR(skb.ifindex != 1, + "ctx_out_ifindex", + "skb->ifindex == %d, expected %d\n", + skb.ifindex, 1); CHECK_ATTR(skb.tstamp != 8, "ctx_out_tstamp", "skb->tstamp == %lld, expected %d\n",