From patchwork Wed Apr 14 18:54:06 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Florent Revest X-Patchwork-Id: 12203569 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 X-Spam-Level: X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, 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 99953C433ED for ; Wed, 14 Apr 2021 18:54:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7AD306120E for ; Wed, 14 Apr 2021 18:54:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1353152AbhDNSzE (ORCPT ); Wed, 14 Apr 2021 14:55:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36070 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348477AbhDNSyo (ORCPT ); Wed, 14 Apr 2021 14:54:44 -0400 Received: from mail-wr1-x42a.google.com (mail-wr1-x42a.google.com [IPv6:2a00:1450:4864:20::42a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3580AC06138E for ; Wed, 14 Apr 2021 11:54:22 -0700 (PDT) Received: by mail-wr1-x42a.google.com with SMTP id k26so4449152wrc.8 for ; Wed, 14 Apr 2021 11:54:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=ZrguiEZQBncRoBtaNZyBwb8KxAudSocLCfIdylJjreQ=; b=lehCtb1Tgya4NICc9Ai4JSrUUbJ32q8UU0LBorVBDVkY76NJ/n0NaDbe7+ADhODkEA K8S5+cE+hbvQISlvebNzrwgZQIKrTkApi8wVTsmurOecQITj6lKCnXKaGgjpE2C3AB5X fFocM6nvYkboc9zxuN7hkWEsyrOF7lKmaILSI= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=ZrguiEZQBncRoBtaNZyBwb8KxAudSocLCfIdylJjreQ=; b=Q5ug5j83pfiht4UvUeAgvpnzJEh/gPWKCYpy6hNtyPqc5x4j5C1ebN+OYNXvgHpPA1 9jk6uxWRRfDCLTldI9tYn8juOs7H+BrlpaKEPAShF09JZTO6GDL+GkP1Ez+RL+7k4rtO +EUMORav+EcsnRmOH+eLIlXkc7OHqSXvPd/zYoD2CXkgfTU2jYG1jeTbFs5+/kYzknvb OmxYc1hEpko1HtfK18PpK2bGI7zupUBtvlc2jCeqAy96hTiLGE2XADj5GZgiPLZJAPXB Joa0n5hFZuhrEMIfOc/nKkvC13Fs1JUxZm/sOeC07nISIAx3gF6nKXGFFek+bcMeID1N ZZ6g== X-Gm-Message-State: AOAM533zEWciCnGaKeef07Jakn4cpX/e0SVBprvl6T1E0pi81oIxgcqD furwtOvuzz0Ga9WlW6Eg5kE2ax8tn6A42Q== X-Google-Smtp-Source: ABdhPJxn5FTTNvsxEwwEHR2sz43bvRkK/fxlGIQ64P4w38wlfAQioCT0ZgFzJek+ZDUgleYl0habtg== X-Received: by 2002:adf:da4f:: with SMTP id r15mr9985927wrl.411.1618426460600; Wed, 14 Apr 2021 11:54:20 -0700 (PDT) Received: from revest.zrh.corp.google.com ([2a00:79e0:42:204:8b2a:41bd:9d62:10d5]) by smtp.gmail.com with ESMTPSA id f12sm253131wrr.61.2021.04.14.11.54.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 14 Apr 2021 11:54:20 -0700 (PDT) From: Florent Revest To: bpf@vger.kernel.org Cc: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, yhs@fb.com, kpsingh@kernel.org, jackmanb@chromium.org, linux-kernel@vger.kernel.org, Florent Revest Subject: [PATCH bpf-next v4 6/6] selftests/bpf: Add a series of tests for bpf_snprintf Date: Wed, 14 Apr 2021 20:54:06 +0200 Message-Id: <20210414185406.917890-7-revest@chromium.org> X-Mailer: git-send-email 2.31.1.295.g9ea45b61b8-goog In-Reply-To: <20210414185406.917890-1-revest@chromium.org> References: <20210414185406.917890-1-revest@chromium.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net The "positive" part tests all format specifiers when things go well. The "negative" part makes sure that incorrect format strings fail at load time. Signed-off-by: Florent Revest --- .../selftests/bpf/prog_tests/snprintf.c | 124 ++++++++++++++++++ .../selftests/bpf/progs/test_snprintf.c | 73 +++++++++++ .../bpf/progs/test_snprintf_single.c | 20 +++ 3 files changed, 217 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/snprintf.c create mode 100644 tools/testing/selftests/bpf/progs/test_snprintf.c create mode 100644 tools/testing/selftests/bpf/progs/test_snprintf_single.c diff --git a/tools/testing/selftests/bpf/prog_tests/snprintf.c b/tools/testing/selftests/bpf/prog_tests/snprintf.c new file mode 100644 index 000000000000..661ffb390b4a --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/snprintf.c @@ -0,0 +1,124 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2021 Google LLC. */ + +#include +#include "test_snprintf.skel.h" +#include "test_snprintf_single.skel.h" + +#define EXP_NUM_OUT "-8 9 96 -424242 1337 DABBAD00" +#define EXP_NUM_RET sizeof(EXP_NUM_OUT) + +#define EXP_IP_OUT "127.000.000.001 0000:0000:0000:0000:0000:0000:0000:0001" +#define EXP_IP_RET sizeof(EXP_IP_OUT) + +/* The third specifier, %pB, depends on compiler inlining so don't check it */ +#define EXP_SYM_OUT "schedule schedule+0x0/" +#define MIN_SYM_RET sizeof(EXP_SYM_OUT) + +/* The third specifier, %p, is a hashed pointer which changes on every reboot */ +#define EXP_ADDR_OUT "0000000000000000 ffff00000add4e55 " +#define EXP_ADDR_RET sizeof(EXP_ADDR_OUT "unknownhashedptr") + +#define EXP_STR_OUT "str1 longstr" +#define EXP_STR_RET sizeof(EXP_STR_OUT) + +#define EXP_OVER_OUT "%over" +#define EXP_OVER_RET 10 + +#define EXP_PAD_OUT " 4 000" +#define EXP_PAD_RET 900007 + +#define EXP_NO_ARG_OUT "simple case" +#define EXP_NO_ARG_RET 12 + +#define EXP_NO_BUF_RET 29 + +void test_snprintf_positive(void) +{ + char exp_addr_out[] = EXP_ADDR_OUT; + char exp_sym_out[] = EXP_SYM_OUT; + struct test_snprintf *skel; + + skel = test_snprintf__open_and_load(); + if (!ASSERT_OK_PTR(skel, "skel_open")) + return; + + if (!ASSERT_OK(test_snprintf__attach(skel), "skel_attach")) + goto cleanup; + + /* trigger tracepoint */ + usleep(1); + + ASSERT_STREQ(skel->bss->num_out, EXP_NUM_OUT, "num_out"); + ASSERT_EQ(skel->bss->num_ret, EXP_NUM_RET, "num_ret"); + + ASSERT_STREQ(skel->bss->ip_out, EXP_IP_OUT, "ip_out"); + ASSERT_EQ(skel->bss->ip_ret, EXP_IP_RET, "ip_ret"); + + ASSERT_OK(memcmp(skel->bss->sym_out, exp_sym_out, + sizeof(exp_sym_out) - 1), "sym_out"); + ASSERT_LT(MIN_SYM_RET, skel->bss->sym_ret, "sym_ret"); + + ASSERT_OK(memcmp(skel->bss->addr_out, exp_addr_out, + sizeof(exp_addr_out) - 1), "addr_out"); + ASSERT_EQ(skel->bss->addr_ret, EXP_ADDR_RET, "addr_ret"); + + ASSERT_STREQ(skel->bss->str_out, EXP_STR_OUT, "str_out"); + ASSERT_EQ(skel->bss->str_ret, EXP_STR_RET, "str_ret"); + + ASSERT_STREQ(skel->bss->over_out, EXP_OVER_OUT, "over_out"); + ASSERT_EQ(skel->bss->over_ret, EXP_OVER_RET, "over_ret"); + + ASSERT_STREQ(skel->bss->pad_out, EXP_PAD_OUT, "pad_out"); + ASSERT_EQ(skel->bss->pad_ret, EXP_PAD_RET, "pad_ret"); + + ASSERT_STREQ(skel->bss->noarg_out, EXP_NO_ARG_OUT, "no_arg_out"); + ASSERT_EQ(skel->bss->noarg_ret, EXP_NO_ARG_RET, "no_arg_ret"); + + ASSERT_EQ(skel->bss->nobuf_ret, EXP_NO_BUF_RET, "no_buf_ret"); + +cleanup: + test_snprintf__destroy(skel); +} + +#define min(a, b) ((a) < (b) ? (a) : (b)) + +/* Loads an eBPF object calling bpf_snprintf with up to 10 characters of fmt */ +static int load_single_snprintf(char *fmt) +{ + struct test_snprintf_single *skel; + int ret; + + skel = test_snprintf_single__open(); + if (!skel) + return -EINVAL; + + memcpy(skel->rodata->fmt, fmt, min(strlen(fmt) + 1, 10)); + + ret = test_snprintf_single__load(skel); + if (!ret) + test_snprintf_single__destroy(skel); + + return ret; +} + +void test_snprintf_negative(void) +{ + ASSERT_OK(load_single_snprintf("valid %d"), "valid usage"); + + ASSERT_ERR(load_single_snprintf("0123456789"), "no terminating zero"); + ASSERT_ERR(load_single_snprintf("%d %d"), "too many specifiers"); + ASSERT_ERR(load_single_snprintf("%pi5"), "invalid specifier 1"); + ASSERT_ERR(load_single_snprintf("%a"), "invalid specifier 2"); + ASSERT_ERR(load_single_snprintf("%"), "invalid specifier 3"); + ASSERT_ERR(load_single_snprintf("\x80"), "non ascii character"); + ASSERT_ERR(load_single_snprintf("\x1"), "non printable character"); +} + +void test_snprintf(void) +{ + if (test__start_subtest("snprintf_positive")) + test_snprintf_positive(); + if (test__start_subtest("snprintf_negative")) + test_snprintf_negative(); +} diff --git a/tools/testing/selftests/bpf/progs/test_snprintf.c b/tools/testing/selftests/bpf/progs/test_snprintf.c new file mode 100644 index 000000000000..951a0301c553 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_snprintf.c @@ -0,0 +1,73 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2021 Google LLC. */ + +#include +#include +#include + +char num_out[64] = {}; +long num_ret = 0; + +char ip_out[64] = {}; +long ip_ret = 0; + +char sym_out[64] = {}; +long sym_ret = 0; + +char addr_out[64] = {}; +long addr_ret = 0; + +char str_out[64] = {}; +long str_ret = 0; + +char over_out[6] = {}; +long over_ret = 0; + +char pad_out[10] = {}; +long pad_ret = 0; + +char noarg_out[64] = {}; +long noarg_ret = 0; + +long nobuf_ret = 0; + +extern const void schedule __ksym; + +SEC("raw_tp/sys_enter") +int handler(const void *ctx) +{ + /* Convenient values to pretty-print */ + const __u8 ex_ipv4[] = {127, 0, 0, 1}; + const __u8 ex_ipv6[] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}; + static const char str1[] = "str1"; + static const char longstr[] = "longstr"; + + /* Integer types */ + num_ret = BPF_SNPRINTF(num_out, sizeof(num_out), + "%d %u %x %li %llu %lX", + -8, 9, 150, -424242, 1337, 0xDABBAD00); + /* IP addresses */ + ip_ret = BPF_SNPRINTF(ip_out, sizeof(ip_out), "%pi4 %pI6", + &ex_ipv4, &ex_ipv6); + /* Symbol lookup formatting */ + sym_ret = BPF_SNPRINTF(sym_out, sizeof(sym_out), "%ps %pS %pB", + &schedule, &schedule, &schedule); + /* Kernel pointers */ + addr_ret = BPF_SNPRINTF(addr_out, sizeof(addr_out), "%pK %px %p", + 0, 0xFFFF00000ADD4E55, 0xFFFF00000ADD4E55); + /* Strings embedding */ + str_ret = BPF_SNPRINTF(str_out, sizeof(str_out), "%s %+05s", + str1, longstr); + /* Overflow */ + over_ret = BPF_SNPRINTF(over_out, sizeof(over_out), "%%overflow"); + /* Padding of fixed width numbers */ + pad_ret = BPF_SNPRINTF(pad_out, sizeof(pad_out), "%5d %0900000X", 4, 4); + /* No args */ + noarg_ret = BPF_SNPRINTF(noarg_out, sizeof(noarg_out), "simple case"); + /* No buffer */ + nobuf_ret = BPF_SNPRINTF(NULL, 0, "only interested in length %d", 60); + + return 0; +} + +char _license[] SEC("license") = "GPL"; diff --git a/tools/testing/selftests/bpf/progs/test_snprintf_single.c b/tools/testing/selftests/bpf/progs/test_snprintf_single.c new file mode 100644 index 000000000000..15ccc5c43803 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_snprintf_single.c @@ -0,0 +1,20 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2021 Google LLC. */ + +#include +#include + +// The format string is filled from the userspace side such that loading fails +static const char fmt[10]; + +SEC("raw_tp/sys_enter") +int handler(const void *ctx) +{ + unsigned long long arg = 42; + + bpf_snprintf(NULL, 0, fmt, &arg, sizeof(arg)); + + return 0; +} + +char _license[] SEC("license") = "GPL";