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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 899BEC19F2C for ; Wed, 3 Aug 2022 16:33:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238347AbiHCQc6 (ORCPT ); Wed, 3 Aug 2022 12:32:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53280 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238536AbiHCQcl (ORCPT ); Wed, 3 Aug 2022 12:32:41 -0400 Received: from mail-pl1-x64a.google.com (mail-pl1-x64a.google.com [IPv6:2607:f8b0:4864:20::64a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 60B6413D49 for ; Wed, 3 Aug 2022 09:32:27 -0700 (PDT) Received: by mail-pl1-x64a.google.com with SMTP id e15-20020a17090301cf00b0016dc94ddcc5so9879477plh.3 for ; Wed, 03 Aug 2022 09:32:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:references:mime-version:message-id:in-reply-to :date:from:to:cc; bh=SukYyRBj0PBu8Y8CxenxhUH2n9Ih4HE5W3Jlsud6SuY=; b=O1BVSSlIXHvyKx+doLjw/vG7Bz5JG26IzeqJbUoO4mtgLWjs0KnD9sCUmIf0dXDaCz gysAAB/TgKCm3OLcse9pNAuxT4UEqE1VAorijZ4s0mJd1gTK/F1ifPchZr/GrhkHywjn YHxpNoDvh7QGW5/aIpaUlxRpXOaOg1xP1/MlmdnR/+T52TJYeNtWdYY7iQnChQ/splEm P4wC/MNidJRZdfGUpQ/s+M1/OaHuLs05OIJpEhMl9rN8kBdQPy3jOqpItJVb0Kxjk+6W +CUKtg1bwM+Mfx103MiSWNCBvjWZJExYrXN9bQhJ+SuG+/lyFHzXqW6OuCdThEEgP6BB ZRsA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:references:mime-version:message-id:in-reply-to :date:x-gm-message-state:from:to:cc; bh=SukYyRBj0PBu8Y8CxenxhUH2n9Ih4HE5W3Jlsud6SuY=; b=nVx/YRJngz6c2TumlvGcyn7Q9eNfFvX88OxKjZMDGe7Q8/mH3kfR7XSzvvhgadI9lU ydBphKn17DfhrBPkPdd2QvGfztKhlDX7u70GLkhV8OE8X0tu+ncZsDwMkFESNQvuS+tt AG3ePmjpTCljG0U52uKeELtiJHwJtEBXqf5kYJbOgDQJwamidTGrawWTHxesdjgfUUos dvBSiwDhye1VZJgy8HLIxQkFnoSGVtgP1m2ZHfigR0pwnFZyROxQi/mr2rhj5OgwlQQs 4AZ6xr0G4b7X8Z3ma4X0XBk27WVItk1VrxkQ+36/uKicAA+JlPaFsR7F6TyETwoe36V0 EZwA== X-Gm-Message-State: ACgBeo2SXeO3qaM/mDUlFDSEPPzsA9MYsndYs00UiY/ZtA4JWKflt6Fb XrAxMJJ2xkviMeIcDMPBf4MI65g1iKqQRzzvybt+rbyGD4frmPRnsV1icef0olzNosaGoESlbJx 67hmFsSJCd/+TS6JFo70mwyvAQIa3l/QUhbE1surbXmJJgFxlMw== X-Google-Smtp-Source: AA6agR5QgfRqQIaDOxHtipqC2inCO0Lu4JEotQIAQEn/5NP+KntnVOT6YGuPU8n8LXA2mxLiFHR9U0E= X-Received: from sdf.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5935]) (user=sdf job=sendgmr) by 2002:a17:90b:3b43:b0:1f4:e3ad:e45a with SMTP id ot3-20020a17090b3b4300b001f4e3ade45amr5720625pjb.87.1659544346576; Wed, 03 Aug 2022 09:32:26 -0700 (PDT) Date: Wed, 3 Aug 2022 09:32:23 -0700 In-Reply-To: <20220803163223.3747004-1-sdf@google.com> Message-Id: <20220803163223.3747004-2-sdf@google.com> Mime-Version: 1.0 References: <20220803163223.3747004-1-sdf@google.com> X-Mailer: git-send-email 2.37.1.455.g008518b4e5-goog Subject: [PATCH bpf-next v2 2/2] selftests/bpf: Excercise bpf_obj_get_info_by_fd for bpf2bpf From: Stanislav Fomichev To: bpf@vger.kernel.org Cc: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, martin.lau@linux.dev, song@kernel.org, yhs@fb.com, john.fastabend@gmail.com, kpsingh@kernel.org, sdf@google.com, haoluo@google.com, jolsa@kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org Apparently, no existing selftest covers it. Add a new one where we load cgroup/bind4 program and attach fentry to it. Calling bpf_obj_get_info_by_fd on the fentry program should return non-zero btf_id/btf_obj_id instead of crashing the kernel. v3: - move into fexit_bpf2bpf.c (Martin) - assert on skel->links.bind_v4_prog (Andrii) - do no close(-1) unconditionally (Andrii) v2: - use ret instead of err in find_prog_btf_id (Hao) - remove verifier log (Hao) - drop if conditional from ASSERT_OK(bpf_obj_get_info_by_fd(...)) (Hao) Signed-off-by: Stanislav Fomichev --- .../selftests/bpf/prog_tests/fexit_bpf2bpf.c | 95 +++++++++++++++++++ 1 file changed, 95 insertions(+) diff --git a/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c b/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c index 02bb8cbf9194..fb62cef35e42 100644 --- a/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c +++ b/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c @@ -3,6 +3,7 @@ #include #include #include +#include "bind4_prog.skel.h" typedef int (*test_cb)(struct bpf_object *obj); @@ -407,6 +408,98 @@ static void test_func_replace_global_func(void) prog_name, false, NULL); } +static int find_prog_btf_id(const char *name, __u32 attach_prog_fd) +{ + struct bpf_prog_info info = {}; + __u32 info_len = sizeof(info); + struct btf *btf; + int ret; + + ret = bpf_obj_get_info_by_fd(attach_prog_fd, &info, &info_len); + if (ret) + return ret; + + if (!info.btf_id) + return -EINVAL; + + btf = btf__load_from_kernel_by_id(info.btf_id); + ret = libbpf_get_error(btf); + if (ret) + return ret; + + ret = btf__find_by_name_kind(btf, name, BTF_KIND_FUNC); + btf__free(btf); + return ret; +} + +static int load_fentry(int attach_prog_fd, int attach_btf_id) +{ + LIBBPF_OPTS(bpf_prog_load_opts, opts, + .expected_attach_type = BPF_TRACE_FENTRY, + .attach_prog_fd = attach_prog_fd, + .attach_btf_id = attach_btf_id, + ); + struct bpf_insn insns[] = { + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_EXIT_INSN(), + }; + + return bpf_prog_load(BPF_PROG_TYPE_TRACING, + "bind4_fentry", + "GPL", + insns, + ARRAY_SIZE(insns), + &opts); +} + +static void test_fentry_to_cgroup_bpf(void) +{ + struct bind4_prog *skel = NULL; + struct bpf_prog_info info = {}; + __u32 info_len = sizeof(info); + int cgroup_fd = -1; + int fentry_fd = -1; + int btf_id; + + cgroup_fd = test__join_cgroup("/fentry_to_cgroup_bpf"); + if (!ASSERT_GE(cgroup_fd, 0, "cgroup_fd")) + return; + + skel = bind4_prog__open_and_load(); + if (!ASSERT_OK_PTR(skel, "skel")) + goto cleanup; + + skel->links.bind_v4_prog = bpf_program__attach_cgroup(skel->progs.bind_v4_prog, cgroup_fd); + if (!ASSERT_OK_PTR(skel->links.bind_v4_prog, "bpf_program__attach_cgroup")) + goto cleanup; + + btf_id = find_prog_btf_id("bind_v4_prog", bpf_program__fd(skel->progs.bind_v4_prog)); + if (!ASSERT_GE(btf_id, 0, "find_prog_btf_id")) + goto cleanup; + + fentry_fd = load_fentry(bpf_program__fd(skel->progs.bind_v4_prog), btf_id); + if (!ASSERT_GE(fentry_fd, 0, "load_fentry")) + goto cleanup; + + /* Make sure bpf_obj_get_info_by_fd works correctly when attaching + * to another BPF program. + */ + + ASSERT_OK(bpf_obj_get_info_by_fd(fentry_fd, &info, &info_len), + "bpf_obj_get_info_by_fd"); + + ASSERT_EQ(info.btf_id, 0, "info.btf_id"); + ASSERT_GT(info.attach_btf_id, 0, "info.attach_btf_id"); + ASSERT_GT(info.attach_btf_obj_id, 0, "info.attach_btf_obj_id"); + +cleanup: + if (cgroup_fd >= 0) + close(cgroup_fd); + if (fentry_fd >= 0) + close(fentry_fd); + bind4_prog__destroy(skel); +} + /* NOTE: affect other tests, must run in serial mode */ void serial_test_fexit_bpf2bpf(void) { @@ -430,4 +523,6 @@ void serial_test_fexit_bpf2bpf(void) test_fmod_ret_freplace(); if (test__start_subtest("func_replace_global_func")) test_func_replace_global_func(); + if (test__start_subtest("fentry_to_cgroup_bpf")) + test_fentry_to_cgroup_bpf(); } -- 2.37.1.455.g008518b4e5-goog