From patchwork Sun Aug 2 21:30:26 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Yakunin X-Patchwork-Id: 1340021 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: incoming-bpf@patchwork.ozlabs.org Delivered-To: patchwork-incoming-bpf@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=bpf-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=yandex-team.ru Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=yandex-team.ru header.i=@yandex-team.ru header.a=rsa-sha256 header.s=default header.b=L98KajXH; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4BKZ2B4slPz9sTd for ; Mon, 3 Aug 2020 07:30:58 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727923AbgHBVa4 (ORCPT ); Sun, 2 Aug 2020 17:30:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45922 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726364AbgHBVaz (ORCPT ); Sun, 2 Aug 2020 17:30:55 -0400 Received: from forwardcorp1p.mail.yandex.net (forwardcorp1p.mail.yandex.net [IPv6:2a02:6b8:0:1472:2741:0:8b6:217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5B769C06174A; Sun, 2 Aug 2020 14:30:55 -0700 (PDT) Received: from vla1-fdfb804fb3f3.qloud-c.yandex.net (vla1-fdfb804fb3f3.qloud-c.yandex.net [IPv6:2a02:6b8:c0d:3199:0:640:fdfb:804f]) by forwardcorp1p.mail.yandex.net (Yandex) with ESMTP id 527C32E14D5; Mon, 3 Aug 2020 00:30:52 +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 sPDLHtjn2X-UqqeVFmv; Mon, 03 Aug 2020 00:30:52 +0300 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yandex-team.ru; s=default; t=1596403852; bh=0+K6ekHFGCKpywJPU+f+Df3pWthE/8ooVEOmlxubSu0=; h=In-Reply-To:Message-Id:References:Date:Subject:To:From:Cc; b=L98KajXH1Cj3Z8cm/ApSrI8aLxaYLMwF08NV+sugpSsbb0C7PQbiqDtPF0jbC8C5b Ebzl5xDpXQvKh2FqYUWVtG6T+x+Y+JVheglaswsGSJIYNkVYegfJn+7CD46K/SJRiE Iv5pwQV2NRGMkaCoviZFUqRN+kEnITu8xn3mNqGU= 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 CwYyvqXlFC-UpjmUkEu; Mon, 03 Aug 2020 00:30:51 +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 00:30:26 +0300 Message-Id: <20200802213026.78731-3-zeil@yandex-team.ru> In-Reply-To: <20200802213026.78731-1-zeil@yandex-team.ru> References: <20200802213026.78731-1-zeil@yandex-team.ru> MIME-Version: 1.0 Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@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",