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=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 84C90C43141 for ; Thu, 14 Nov 2019 18:58:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5B1502071B for ; Thu, 14 Nov 2019 18:58:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573757888; bh=odyGhZy7Gn7aCg3XJKdHGR9aDD/W4XRMfcyZKyowjrE=; h=From:To:CC:Subject:Date:In-Reply-To:References:List-ID:From; b=Jq100p4wjzju6nNFYTAGiL41S3D6skivFo6jMqTjz2HhsIAzaVn8+DnAbu0OEDNPZ NH2jdGldGm7ffAvBOetQJsUq0qTLc98TQff/VlCXimZxsK6JcJOWPy9FuALqL+XqzY Z149gy+uryEzTC4cJ6YwfFveDqvM0lFvSNrzZ7wc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727344AbfKNS6H convert rfc822-to-8bit (ORCPT ); Thu, 14 Nov 2019 13:58:07 -0500 Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:44808 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727324AbfKNS6G (ORCPT ); Thu, 14 Nov 2019 13:58:06 -0500 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 xAEIhO0x030182 for ; Thu, 14 Nov 2019 10:58:04 -0800 Received: from maileast.thefacebook.com ([163.114.130.16]) by mx0a-00082601.pphosted.com with ESMTP id 2w8qj9e1hp-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128 verify=NOT) for ; Thu, 14 Nov 2019 10:58:04 -0800 Received: from 2401:db00:2050:5076:face:0:1f:0 (2620:10d:c0a8:1b::d) by mail.thefacebook.com (2620:10d:c0a8:82::f) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1713.5; Thu, 14 Nov 2019 10:58:03 -0800 Received: by devbig007.ftw2.facebook.com (Postfix, from userid 572438) id 0B90C76071B; Thu, 14 Nov 2019 10:58:02 -0800 (PST) Smtp-Origin-Hostprefix: devbig From: Alexei Starovoitov Smtp-Origin-Hostname: devbig007.ftw2.facebook.com To: CC: , , , , Smtp-Origin-Cluster: ftw2c04 Subject: [PATCH v4 bpf-next 20/20] selftests/bpf: Add a test for attaching BPF prog to another BPF prog and subprog Date: Thu, 14 Nov 2019 10:57:20 -0800 Message-ID: <20191114185720.1641606-21-ast@kernel.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191114185720.1641606-1-ast@kernel.org> References: <20191114185720.1641606-1-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=2.50.10434:6.0.95,18.0.572 definitions=2019-11-14_05:2019-11-14,2019-11-14 signatures=0 X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 mlxscore=0 malwarescore=0 bulkscore=0 spamscore=0 lowpriorityscore=0 priorityscore=1501 clxscore=1034 mlxlogscore=781 suspectscore=1 adultscore=0 phishscore=0 impostorscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-1910280000 definitions=main-1911140157 X-FB-Internal: deliver Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Add a test that attaches one FEXIT program to main sched_cls networking program and two other FEXIT programs to subprograms. All three tracing programs access return values and skb->len of networking program and subprograms. Signed-off-by: Alexei Starovoitov Acked-by: Song Liu Acked-by: Andrii Nakryiko --- .../selftests/bpf/prog_tests/fexit_bpf2bpf.c | 76 ++++++++++++++++ .../selftests/bpf/progs/fexit_bpf2bpf.c | 91 +++++++++++++++++++ 2 files changed, 167 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c create mode 100644 tools/testing/selftests/bpf/progs/fexit_bpf2bpf.c diff --git a/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c b/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c new file mode 100644 index 000000000000..15c7378362dd --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c @@ -0,0 +1,76 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2019 Facebook */ +#include + +#define PROG_CNT 3 + +void test_fexit_bpf2bpf(void) +{ + const char *prog_name[PROG_CNT] = { + "fexit/test_pkt_access", + "fexit/test_pkt_access_subprog1", + "fexit/test_pkt_access_subprog2", + }; + struct bpf_object *obj = NULL, *pkt_obj; + int err, pkt_fd, i; + struct bpf_link *link[PROG_CNT] = {}; + struct bpf_program *prog[PROG_CNT]; + __u32 duration, retval; + struct bpf_map *data_map; + const int zero = 0; + u64 result[PROG_CNT]; + + err = bpf_prog_load("./test_pkt_access.o", BPF_PROG_TYPE_UNSPEC, + &pkt_obj, &pkt_fd); + if (CHECK(err, "prog_load sched cls", "err %d errno %d\n", err, errno)) + return; + DECLARE_LIBBPF_OPTS(bpf_object_open_opts, opts, + .attach_prog_fd = pkt_fd, + ); + + obj = bpf_object__open_file("./fexit_bpf2bpf.o", &opts); + if (CHECK(IS_ERR_OR_NULL(obj), "obj_open", + "failed to open fexit_bpf2bpf: %ld\n", + PTR_ERR(obj))) + goto close_prog; + + err = bpf_object__load(obj); + if (CHECK(err, "obj_load", "err %d\n", err)) + goto close_prog; + + for (i = 0; i < PROG_CNT; i++) { + prog[i] = bpf_object__find_program_by_title(obj, prog_name[i]); + if (CHECK(!prog[i], "find_prog", "prog %s not found\n", prog_name[i])) + goto close_prog; + link[i] = bpf_program__attach_trace(prog[i]); + if (CHECK(IS_ERR(link[i]), "attach_trace", "failed to link\n")) + goto close_prog; + } + data_map = bpf_object__find_map_by_name(obj, "fexit_bp.bss"); + if (CHECK(!data_map, "find_data_map", "data map not found\n")) + 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); + + err = bpf_map_lookup_elem(bpf_map__fd(data_map), &zero, &result); + if (CHECK(err, "get_result", + "failed to get output data: %d\n", err)) + goto close_prog; + + for (i = 0; i < PROG_CNT; i++) + if (CHECK(result[i] != 1, "result", "fexit_bpf2bpf failed err %ld\n", + result[i])) + goto close_prog; + +close_prog: + for (i = 0; i < PROG_CNT; i++) + if (!IS_ERR_OR_NULL(link[i])) + bpf_link__destroy(link[i]); + if (!IS_ERR_OR_NULL(obj)) + bpf_object__close(obj); + bpf_object__close(pkt_obj); +} diff --git a/tools/testing/selftests/bpf/progs/fexit_bpf2bpf.c b/tools/testing/selftests/bpf/progs/fexit_bpf2bpf.c new file mode 100644 index 000000000000..981f0474da5a --- /dev/null +++ b/tools/testing/selftests/bpf/progs/fexit_bpf2bpf.c @@ -0,0 +1,91 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2019 Facebook */ +#include +#include "bpf_helpers.h" + +struct sk_buff { + unsigned int len; +}; + +struct args { + struct sk_buff *skb; + ks32 ret; +}; +static volatile __u64 test_result; +SEC("fexit/test_pkt_access") +int test_main(struct args *ctx) +{ + struct sk_buff *skb = ctx->skb; + int len; + + __builtin_preserve_access_index(({ + len = skb->len; + })); + if (len != 74 || ctx->ret != 0) + return 0; + test_result = 1; + return 0; +} + +struct args_subprog1 { + struct sk_buff *skb; + ks32 ret; +}; +static volatile __u64 test_result_subprog1; +SEC("fexit/test_pkt_access_subprog1") +int test_subprog1(struct args_subprog1 *ctx) +{ + struct sk_buff *skb = ctx->skb; + int len; + + __builtin_preserve_access_index(({ + len = skb->len; + })); + if (len != 74 || ctx->ret != 148) + return 0; + test_result_subprog1 = 1; + return 0; +} + +/* Though test_pkt_access_subprog2() is defined in C as: + * static __attribute__ ((noinline)) + * int test_pkt_access_subprog2(int val, volatile struct __sk_buff *skb) + * { + * return skb->len * val; + * } + * llvm optimizations remove 'int val' argument and generate BPF assembly: + * r0 = *(u32 *)(r1 + 0) + * w0 <<= 1 + * exit + * In such case the verifier falls back to conservative and + * tracing program can access arguments and return value as u64 + * instead of accurate types. + */ +struct args_subprog2 { + ku64 args[5]; + ku64 ret; +}; +static volatile __u64 test_result_subprog2; +SEC("fexit/test_pkt_access_subprog2") +int test_subprog2(struct args_subprog2 *ctx) +{ + struct sk_buff *skb = (void *)ctx->args[0]; + __u64 ret; + int len; + + bpf_probe_read_kernel(&len, sizeof(len), + __builtin_preserve_access_index(&skb->len)); + + ret = ctx->ret; + /* bpf_prog_load() loads "test_pkt_access.o" with BPF_F_TEST_RND_HI32 + * which randomizes upper 32 bits after BPF_ALU32 insns. + * Hence after 'w0 <<= 1' upper bits of $rax are random. + * That is expected and correct. Trim them. + */ + ret = (__u32) ret; + if (len != 74 || ret != 148) + return 0; + test_result_subprog2 = 1; + return 0; +} +char _license[] SEC("license") = "GPL"; -- 2.23.0