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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 A2DA4ECE596 for ; Thu, 10 Oct 2019 04:15:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7E5E020B7C for ; Thu, 10 Oct 2019 04:15:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570680937; bh=pPTVOGrlY/V5fR4GAwKQ7KVGHRGb2zyRLg9cVtGfKSE=; h=From:To:CC:Subject:Date:In-Reply-To:References:List-ID:From; b=1Q7lcLGm2kQ3zfx/RG+um3fV+ZGnuAsS85yd6e/N4bSCOaYuIDenGVPYIBwMbx7YT H/pioyb50ofAtjg/zcVSYbqmFgQGbWz25D5z/m1mbc/7A9bAAXmC6c/DdKdTI1V0wJ f+K0jtW2dyMYeUVV7qdQovbTyqE7jUZbpV3yTHw0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732850AbfJJEPg convert rfc822-to-8bit (ORCPT ); Thu, 10 Oct 2019 00:15:36 -0400 Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:58366 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732828AbfJJEPa (ORCPT ); Thu, 10 Oct 2019 00:15:30 -0400 Received: from pps.filterd (m0148461.ppops.net [127.0.0.1]) by mx0a-00082601.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id x9A4E7QQ014734 for ; Wed, 9 Oct 2019 21:15:29 -0700 Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com with ESMTP id 2vhfsduu0c-2 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Wed, 09 Oct 2019 21:15:29 -0700 Received: from 2401:db00:2050:5102:face:0:3b:0 (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:83::7) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1713.5; Wed, 9 Oct 2019 21:15:28 -0700 Received: by devbig007.ftw2.facebook.com (Postfix, from userid 572438) id B441F760CF9; Wed, 9 Oct 2019 21:15:27 -0700 (PDT) Smtp-Origin-Hostprefix: devbig From: Alexei Starovoitov Smtp-Origin-Hostname: devbig007.ftw2.facebook.com To: CC: , , , , Smtp-Origin-Cluster: ftw2c04 Subject: [PATCH v2 bpf-next 12/12] selftests/bpf: add kfree_skb raw_tp test Date: Wed, 9 Oct 2019 21:15:03 -0700 Message-ID: <20191010041503.2526303-13-ast@kernel.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191010041503.2526303-1-ast@kernel.org> References: <20191010041503.2526303-1-ast@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8BIT X-FB-Internal: Safe Content-Type: text/plain X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.95,1.0.8 definitions=2019-10-10_02:2019-10-08,2019-10-10 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 bulkscore=0 phishscore=0 priorityscore=1501 adultscore=0 lowpriorityscore=0 suspectscore=4 clxscore=1034 mlxlogscore=999 spamscore=0 mlxscore=0 malwarescore=0 impostorscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-1908290000 definitions=main-1910100037 X-FB-Internal: deliver Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Load basic cls_bpf program. Load raw_tracepoint program and attach to kfree_skb raw tracepoint. Trigger cls_bpf via prog_test_run. At the end of test_run kernel will call kfree_skb which will trigger trace_kfree_skb tracepoint. Which will call our raw_tracepoint program. Which will take that skb and will dump it into perf ring buffer. Check that user space received correct packet. Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko --- .../selftests/bpf/prog_tests/kfree_skb.c | 90 +++++++++++++++++++ tools/testing/selftests/bpf/progs/kfree_skb.c | 74 +++++++++++++++ 2 files changed, 164 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/kfree_skb.c create mode 100644 tools/testing/selftests/bpf/progs/kfree_skb.c diff --git a/tools/testing/selftests/bpf/prog_tests/kfree_skb.c b/tools/testing/selftests/bpf/prog_tests/kfree_skb.c new file mode 100644 index 000000000000..0cf91b6bf276 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/kfree_skb.c @@ -0,0 +1,90 @@ +// SPDX-License-Identifier: GPL-2.0 +#include + +static void on_sample(void *ctx, int cpu, void *data, __u32 size) +{ + int ifindex = *(int *)data, duration = 0; + struct ipv6_packet *pkt_v6 = data + 4; + + if (ifindex != 1) + /* spurious kfree_skb not on loopback device */ + return; + if (CHECK(size != 76, "check_size", "size %u != 76\n", size)) + return; + if (CHECK(pkt_v6->eth.h_proto != 0xdd86, "check_eth", + "h_proto %x\n", pkt_v6->eth.h_proto)) + return; + if (CHECK(pkt_v6->iph.nexthdr != 6, "check_ip", + "iph.nexthdr %x\n", pkt_v6->iph.nexthdr)) + return; + if (CHECK(pkt_v6->tcp.doff != 5, "check_tcp", + "tcp.doff %x\n", pkt_v6->tcp.doff)) + return; + + *(bool *)ctx = true; +} + +void test_kfree_skb(void) +{ + struct bpf_prog_load_attr attr = { + .file = "./kfree_skb.o", + .log_level = 2, + }; + + struct bpf_object *obj, *obj2 = NULL; + struct perf_buffer_opts pb_opts = {}; + struct perf_buffer *pb = NULL; + struct bpf_link *link = NULL; + struct bpf_map *perf_buf_map; + struct bpf_program *prog; + __u32 duration, retval; + int err, pkt_fd, kfree_skb_fd; + bool passed = false; + + err = bpf_prog_load("./test_pkt_access.o", BPF_PROG_TYPE_SCHED_CLS, &obj, &pkt_fd); + if (CHECK(err, "prog_load sched cls", "err %d errno %d\n", err, errno)) + return; + + err = bpf_prog_load_xattr(&attr, &obj2, &kfree_skb_fd); + if (CHECK(err, "prog_load raw tp", "err %d errno %d\n", err, errno)) + goto close_prog; + + prog = bpf_object__find_program_by_title(obj2, "raw_tracepoint/kfree_skb"); + if (CHECK(!prog, "find_prog", "prog kfree_skb not found\n")) + goto close_prog; + link = bpf_program__attach_raw_tracepoint(prog, NULL); + if (CHECK(IS_ERR(link), "attach_raw_tp", "err %ld\n", PTR_ERR(link))) + goto close_prog; + + perf_buf_map = bpf_object__find_map_by_name(obj2, "perf_buf_map"); + if (CHECK(!perf_buf_map, "find_perf_buf_map", "not found\n")) + goto close_prog; + + /* set up perf buffer */ + pb_opts.sample_cb = on_sample; + pb_opts.ctx = &passed; + pb = perf_buffer__new(bpf_map__fd(perf_buf_map), 1, &pb_opts); + if (CHECK(IS_ERR(pb), "perf_buf__new", "err %ld\n", PTR_ERR(pb))) + goto close_prog; + + err = bpf_prog_test_run(pkt_fd, 1, &pkt_v6, sizeof(pkt_v6), + NULL, NULL, &retval, &duration); + CHECK(err || retval, "ipv6", + "err %d errno %d retval %d duration %d\n", + err, errno, retval, duration); + + /* read perf buffer */ + err = perf_buffer__poll(pb, 100); + if (CHECK(err < 0, "perf_buffer__poll", "err %d\n", err)) + goto close_prog; + /* make sure kfree_skb program was triggered + * and it sent expected skb into ring buffer + */ + CHECK_FAIL(!passed); +close_prog: + perf_buffer__free(pb); + if (!IS_ERR_OR_NULL(link)) + bpf_link__destroy(link); + bpf_object__close(obj); + bpf_object__close(obj2); +} diff --git a/tools/testing/selftests/bpf/progs/kfree_skb.c b/tools/testing/selftests/bpf/progs/kfree_skb.c new file mode 100644 index 000000000000..fc25797cc64d --- /dev/null +++ b/tools/testing/selftests/bpf/progs/kfree_skb.c @@ -0,0 +1,74 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (c) 2019 Facebook +#include +#include "bpf_helpers.h" + +char _license[] SEC("license") = "GPL"; +struct { + __uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY); + __uint(key_size, sizeof(int)); + __uint(value_size, sizeof(int)); +} perf_buf_map SEC(".maps"); + +#define _(P) (__builtin_preserve_access_index(P)) + +/* define few struct-s that bpf program needs to access */ +struct callback_head { + struct callback_head *next; + void (*func)(struct callback_head *head); +}; +struct dev_ifalias { + struct callback_head rcuhead; +}; + +struct net_device /* same as kernel's struct net_device */ { + int ifindex; + struct dev_ifalias *ifalias; +}; + +struct sk_buff { + /* field names and sizes should match to those in the kernel */ + unsigned int len, data_len; + __u16 mac_len, hdr_len, queue_mapping; + struct net_device *dev; + /* order of the fields doesn't matter */ +}; + +/* copy arguments from + * include/trace/events/skb.h: + * TRACE_EVENT(kfree_skb, + * TP_PROTO(struct sk_buff *skb, void *location), + * + * into struct below: + */ +struct trace_kfree_skb { + struct sk_buff *skb; + void *location; +}; + +SEC("raw_tracepoint/kfree_skb") +int trace_kfree_skb(struct trace_kfree_skb *ctx) +{ + struct sk_buff *skb = ctx->skb; + struct net_device *dev; + int ifindex; + struct callback_head *ptr; + void *func; + + __builtin_preserve_access_index(({ + dev = skb->dev; + ifindex = dev->ifindex; + ptr = dev->ifalias->rcuhead.next; + func = ptr->func; + })); + + bpf_printk("rcuhead.next %llx func %llx\n", ptr, func); + bpf_printk("skb->len %d\n", _(skb->len)); + bpf_printk("skb->queue_mapping %d\n", _(skb->queue_mapping)); + bpf_printk("dev->ifindex %d\n", ifindex); + + /* send first 72 byte of the packet to user space */ + bpf_skb_output(skb, &perf_buf_map, (72ull << 32) | BPF_F_CURRENT_CPU, + &ifindex, sizeof(ifindex)); + return 0; +} -- 2.23.0