From patchwork Thu May 19 15:06:10 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yuntao Wang X-Patchwork-Id: 12855250 X-Patchwork-Delegate: bpf@iogearbox.net 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 175D1C433FE for ; Thu, 19 May 2022 15:07:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240506AbiESPHB (ORCPT ); Thu, 19 May 2022 11:07:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58814 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235070AbiESPGo (ORCPT ); Thu, 19 May 2022 11:06:44 -0400 Received: from mail-pg1-x533.google.com (mail-pg1-x533.google.com [IPv6:2607:f8b0:4864:20::533]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AB1482C13F; Thu, 19 May 2022 08:06:42 -0700 (PDT) Received: by mail-pg1-x533.google.com with SMTP id v10so5307799pgl.11; Thu, 19 May 2022 08:06:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=EucD8D1Hopx9myMTmlYjgrvRoh4xz50vqffBCpTlf4s=; b=HLb2/gkOCAtGsnmd/tHYpzeQNKrQwcnhkUrQOoA3qLFXMnX9uHH0Xwbjsv0OqX0TuS 8VWMsmu2QrlHt9/aMusoRbhlCGPlVY62+AQ28zFaOyNMT77Ysiwmkyi3cz60AmUiKmQr MK6BY3YhY51Yuv/uTFrnB5APmzMseJUq/2WG2B7h4ebbRkad2HSLU4gBnoGXvCXZxw5E vvE+SA6997pIrJOBrHo+kBK6jglT7GpBZIKibhl08djLAEIE1/J73/CGo1v47Me8R9ti v0uCTY0JEtRPciErtZ5EzY2tLjpRzX8PSpo64/eOKih5zgPtSXuwYRTv0WeucnkpOEGW FAxg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=EucD8D1Hopx9myMTmlYjgrvRoh4xz50vqffBCpTlf4s=; b=DzsNVwgvlmAH2J0RPaNPchrsNIewb1ApVvJYJNTu7sItfj+7/Q4/LXUhmEXoiZ7rZ+ Hd+alrwloag7eblWOs86whPGz7y2t/7PQePFH+QUx5CHa3SDHVAhjlykp8t7B7LlIDVw MSI+DnBfv/GWA9olUiP9rpAyGRzybozRHWCLoT7qOGTPI2U6Y2/6kgpSDJzd9MHFg8/g /+NP4JSKnJumPgjgHCM67J2qJqXLacUug+Wne8LA6aOgDWB4wVj/w7V3HrGRbANDEHe+ 1YRiVckN/xZfuox09MYush9rlZRdM7ieyK00f+rQysdVqK3ttsjgl6hr2CaoomNKVdpN ZEeg== X-Gm-Message-State: AOAM5303ut4jQURr4R6CnpSTTte9VNG2vANAZFBkhPnU9ZCoVh7MCEQd 9BXQCzG6A6l56r2LsZCFXSc= X-Google-Smtp-Source: ABdhPJwS7q92N95rTBohYsdxSKlwUJWCJnPq9iyzHkSKMq4zkvXpHiLIZMhK9oAL2vGPJpFOZnfAFQ== X-Received: by 2002:a63:6bc2:0:b0:3c2:13cc:1dec with SMTP id g185-20020a636bc2000000b003c213cc1decmr4316155pgc.263.1652972802133; Thu, 19 May 2022 08:06:42 -0700 (PDT) Received: from localhost.localdomain ([223.212.58.71]) by smtp.gmail.com with ESMTPSA id n22-20020a056a0007d600b0050dc7628139sm4536687pfu.19.2022.05.19.08.06.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 19 May 2022 08:06:41 -0700 (PDT) From: Yuntao Wang To: andrii.nakryiko@gmail.com Cc: andrii@kernel.org, ast@kernel.org, bpf@vger.kernel.org, daniel@iogearbox.net, john.fastabend@gmail.com, jolsa@kernel.org, kafai@fb.com, kpsingh@kernel.org, kuifeng@fb.com, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, netdev@vger.kernel.org, shuah@kernel.org, songliubraving@fb.com, sunyucong@gmail.com, toke@redhat.com, yhs@fb.com, ytcoode@gmail.com Subject: [PATCH bpf-next v2] selftests/bpf: Add missing trampoline program type to trampoline_count test Date: Thu, 19 May 2022 23:06:10 +0800 Message-Id: <20220519150610.601313-1-ytcoode@gmail.com> X-Mailer: git-send-email 2.36.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net Currently the trampoline_count test doesn't include any fmod_ret bpf programs, fix it to make the test cover all possible trampoline program types. Since fmod_ret bpf programs can't be attached to __set_task_comm function, as it's neither whitelisted for error injection nor a security hook, change it to bpf_modify_return_test. This patch also does some other cleanups such as removing duplicate code, dropping inconsistent comments, etc. Signed-off-by: Yuntao Wang Acked-by: Yonghong Song --- v1->v2: call bpf_prog_test_run() to trigger bpf_modify_return_test in kernel include/linux/bpf.h | 2 +- .../bpf/prog_tests/trampoline_count.c | 134 +++++++----------- .../bpf/progs/test_trampoline_count.c | 16 ++- 3 files changed, 61 insertions(+), 91 deletions(-) diff --git a/include/linux/bpf.h b/include/linux/bpf.h index c107392b0ba7..cb01f247e05f 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -724,7 +724,7 @@ struct btf_func_model { #define BPF_TRAMP_F_RET_FENTRY_RET BIT(4) /* Each call __bpf_prog_enter + call bpf_func + call __bpf_prog_exit is ~50 - * bytes on x86. Pick a number to fit into BPF_IMAGE_SIZE / 2 + * bytes on x86. */ #define BPF_MAX_TRAMP_LINKS 38 diff --git a/tools/testing/selftests/bpf/prog_tests/trampoline_count.c b/tools/testing/selftests/bpf/prog_tests/trampoline_count.c index 9c795ee52b7b..b0acbda6dbf5 100644 --- a/tools/testing/selftests/bpf/prog_tests/trampoline_count.c +++ b/tools/testing/selftests/bpf/prog_tests/trampoline_count.c @@ -1,126 +1,94 @@ // SPDX-License-Identifier: GPL-2.0-only #define _GNU_SOURCE -#include -#include #include #define MAX_TRAMP_PROGS 38 struct inst { struct bpf_object *obj; - struct bpf_link *link_fentry; - struct bpf_link *link_fexit; + struct bpf_link *link; }; -static int test_task_rename(void) -{ - int fd, duration = 0, err; - char buf[] = "test_overhead"; - - fd = open("/proc/self/comm", O_WRONLY|O_TRUNC); - if (CHECK(fd < 0, "open /proc", "err %d", errno)) - return -1; - err = write(fd, buf, sizeof(buf)); - if (err < 0) { - CHECK(err < 0, "task rename", "err %d", errno); - close(fd); - return -1; - } - close(fd); - return 0; -} - -static struct bpf_link *load(struct bpf_object *obj, const char *name) +static struct bpf_program *load_prog(char *file, char *name, struct inst *inst) { + struct bpf_object *obj; struct bpf_program *prog; - int duration = 0; + int err; + + obj = bpf_object__open_file(file, NULL); + if (!ASSERT_OK_PTR(obj, "obj_open_file")) + return NULL; + + inst->obj = obj; + + err = bpf_object__load(obj); + if (!ASSERT_OK(err, "obj_load")) + return NULL; prog = bpf_object__find_program_by_name(obj, name); - if (CHECK(!prog, "find_probe", "prog '%s' not found\n", name)) - return ERR_PTR(-EINVAL); - return bpf_program__attach_trace(prog); + if (!ASSERT_OK_PTR(prog, "obj_find_prog")) + return NULL; + + return prog; } /* TODO: use different target function to run in concurrent mode */ void serial_test_trampoline_count(void) { - const char *fentry_name = "prog1"; - const char *fexit_name = "prog2"; - const char *object = "test_trampoline_count.o"; - struct inst inst[MAX_TRAMP_PROGS] = {}; - int err, i = 0, duration = 0; - struct bpf_object *obj; + char *file = "test_trampoline_count.o"; + char *const progs[] = { "fentry_test", "fmod_ret_test", "fexit_test" }; + struct inst inst[MAX_TRAMP_PROGS + 1] = {}; + struct bpf_program *prog; struct bpf_link *link; - char comm[16] = {}; + int prog_fd, err, i; + LIBBPF_OPTS(bpf_test_run_opts, opts); /* attach 'allowed' trampoline programs */ for (i = 0; i < MAX_TRAMP_PROGS; i++) { - obj = bpf_object__open_file(object, NULL); - if (!ASSERT_OK_PTR(obj, "obj_open_file")) { - obj = NULL; + prog = load_prog(file, progs[i % ARRAY_SIZE(progs)], &inst[i]); + if (!prog) goto cleanup; - } - err = bpf_object__load(obj); - if (CHECK(err, "obj_load", "err %d\n", err)) + link = bpf_program__attach(prog); + if (!ASSERT_OK_PTR(link, "attach_prog")) goto cleanup; - inst[i].obj = obj; - obj = NULL; - - if (rand() % 2) { - link = load(inst[i].obj, fentry_name); - if (!ASSERT_OK_PTR(link, "attach_prog")) { - link = NULL; - goto cleanup; - } - inst[i].link_fentry = link; - } else { - link = load(inst[i].obj, fexit_name); - if (!ASSERT_OK_PTR(link, "attach_prog")) { - link = NULL; - goto cleanup; - } - inst[i].link_fexit = link; - } + + inst[i].link = link; } /* and try 1 extra.. */ - obj = bpf_object__open_file(object, NULL); - if (!ASSERT_OK_PTR(obj, "obj_open_file")) { - obj = NULL; + prog = load_prog(file, "fmod_ret_test", &inst[i]); + if (!prog) goto cleanup; - } - - err = bpf_object__load(obj); - if (CHECK(err, "obj_load", "err %d\n", err)) - goto cleanup_extra; /* ..that needs to fail */ - link = load(obj, fentry_name); - err = libbpf_get_error(link); - if (!ASSERT_ERR_PTR(link, "cannot attach over the limit")) { - bpf_link__destroy(link); - goto cleanup_extra; + link = bpf_program__attach(prog); + if (!ASSERT_ERR_PTR(link, "attach_prog")) { + inst[i].link = link; + goto cleanup; } /* with E2BIG error */ - ASSERT_EQ(err, -E2BIG, "proper error check"); - ASSERT_EQ(link, NULL, "ptr_is_null"); + if (!ASSERT_EQ(libbpf_get_error(link), -E2BIG, "E2BIG")) + goto cleanup; + if (!ASSERT_EQ(link, NULL, "ptr_is_null")) + goto cleanup; /* and finaly execute the probe */ - if (CHECK_FAIL(prctl(PR_GET_NAME, comm, 0L, 0L, 0L))) - goto cleanup_extra; - CHECK_FAIL(test_task_rename()); - CHECK_FAIL(prctl(PR_SET_NAME, comm, 0L, 0L, 0L)); + prog_fd = bpf_program__fd(prog); + if (!ASSERT_GE(prog_fd, 0, "bpf_program__fd")) + goto cleanup; + + err = bpf_prog_test_run_opts(prog_fd, &opts); + if (!ASSERT_OK(err, "bpf_prog_test_run_opts")) + goto cleanup; + + ASSERT_EQ(opts.retval & 0xffff, 4, "bpf_modify_return_test.result"); + ASSERT_EQ(opts.retval >> 16, 1, "bpf_modify_return_test.side_effect"); -cleanup_extra: - bpf_object__close(obj); cleanup: - if (i >= MAX_TRAMP_PROGS) - i = MAX_TRAMP_PROGS - 1; for (; i >= 0; i--) { - bpf_link__destroy(inst[i].link_fentry); - bpf_link__destroy(inst[i].link_fexit); + bpf_link__destroy(inst[i].link); bpf_object__close(inst[i].obj); } } diff --git a/tools/testing/selftests/bpf/progs/test_trampoline_count.c b/tools/testing/selftests/bpf/progs/test_trampoline_count.c index f030e469d05b..7765720da7d5 100644 --- a/tools/testing/selftests/bpf/progs/test_trampoline_count.c +++ b/tools/testing/selftests/bpf/progs/test_trampoline_count.c @@ -1,20 +1,22 @@ // SPDX-License-Identifier: GPL-2.0 -#include -#include #include #include #include -struct task_struct; +SEC("fentry/bpf_modify_return_test") +int BPF_PROG(fentry_test, int a, int *b) +{ + return 0; +} -SEC("fentry/__set_task_comm") -int BPF_PROG(prog1, struct task_struct *tsk, const char *buf, bool exec) +SEC("fmod_ret/bpf_modify_return_test") +int BPF_PROG(fmod_ret_test, int a, int *b, int ret) { return 0; } -SEC("fexit/__set_task_comm") -int BPF_PROG(prog2, struct task_struct *tsk, const char *buf, bool exec) +SEC("fexit/bpf_modify_return_test") +int BPF_PROG(fexit_test, int a, int *b, int ret) { return 0; }