From patchwork Mon Aug 3 09:05:45 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Yakunin X-Patchwork-Id: 1340204 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=C5PTJHjA; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4BKsSN6V9nz9sTX for ; Mon, 3 Aug 2020 19:06:12 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726806AbgHCJGL (ORCPT ); Mon, 3 Aug 2020 05:06:11 -0400 Received: from forwardcorp1p.mail.yandex.net ([77.88.29.217]:38326 "EHLO forwardcorp1p.mail.yandex.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725926AbgHCJGG (ORCPT ); Mon, 3 Aug 2020 05:06:06 -0400 Received: from iva8-d077482f1536.qloud-c.yandex.net (iva8-d077482f1536.qloud-c.yandex.net [IPv6:2a02:6b8:c0c:2f26:0:640:d077:482f]) by forwardcorp1p.mail.yandex.net (Yandex) with ESMTP id DEA692E14FC; Mon, 3 Aug 2020 12:06:03 +0300 (MSK) Received: from iva8-88b7aa9dc799.qloud-c.yandex.net (iva8-88b7aa9dc799.qloud-c.yandex.net [2a02:6b8:c0c:77a0:0:640:88b7:aa9d]) by iva8-d077482f1536.qloud-c.yandex.net (mxbackcorp/Yandex) with ESMTP id V7kn8eU4FZ-62t8r06x; Mon, 03 Aug 2020 12:06:03 +0300 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yandex-team.ru; s=default; t=1596445563; bh=Oo66nsRaElryOZye3EqBLW8xrT36MuCfruXoPKVcSIE=; h=In-Reply-To:Message-Id:References:Date:Subject:To:From:Cc; b=C5PTJHjAH7WEn2JiVq7Dgqxlnt0aab036S0zJCKh/6wPHppVHlq9ve3GuEH2zoC8t IrSmPVpqqXir935Gqax0B2xYwGONTSX+PpofnNl4VAOJsJhNxWigJVSrZGdsCuMMKG kGAKFxnriMgUHjKzEALEtktI8TRYev21DIoL63tE= Authentication-Results: iva8-d077482f1536.qloud-c.yandex.net; dkim=pass header.i=@yandex-team.ru Received: from 178.154.163.76-vpn.dhcp.yndx.net (178.154.163.76-vpn.dhcp.yndx.net [178.154.163.76]) by iva8-88b7aa9dc799.qloud-c.yandex.net (smtpcorp/Yandex) with ESMTPSA id 1ZDFznne1R-62iCIIr9; Mon, 03 Aug 2020 12:06:02 +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: eric.dumazet@gmail.com, sdf@google.com Subject: [PATCH bpf-next v6 2/2] bpf: allow to specify ifindex for skb in bpf_prog_test_run_skb Date: Mon, 3 Aug 2020 12:05:45 +0300 Message-Id: <20200803090545.82046-3-zeil@yandex-team.ru> In-Reply-To: <20200803090545.82046-1-zeil@yandex-team.ru> References: <20200803090545.82046-1-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 736a596..99eb8c6 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",