From patchwork Fri Sep 18 13:34:33 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alan Maguire X-Patchwork-Id: 255194 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=-15.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, UNPARSEABLE_RELAY, 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 4C9E5C43466 for ; Fri, 18 Sep 2020 13:38:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F3E0420795 for ; Fri, 18 Sep 2020 13:38:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="CoVWrCJe" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726835AbgIRNir (ORCPT ); Fri, 18 Sep 2020 09:38:47 -0400 Received: from aserp2120.oracle.com ([141.146.126.78]:45546 "EHLO aserp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726174AbgIRNip (ORCPT ); Fri, 18 Sep 2020 09:38:45 -0400 Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 08IDZ0he150483; Fri, 18 Sep 2020 13:37:55 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id : in-reply-to : references; s=corp-2020-01-29; bh=x8ujQc1Fx7UQPvBWNaGavc0v04VsxUh0B+ZiyxF7QVw=; b=CoVWrCJe3Ktnh1PhDn7pbX9iRc1V8qsemwxjcPTMS8hCc0f2zNbbM97FQPh3YEInLlFK tq8y5Vd24Z0uE2Noe1nPrgwJGnJIXV1EB+PwW4J5wOPQUjJ0WPfEEhPSouTx4SLGZAKL WPJE6i2ezVDkxnplCU7Rs/ERjDIzTNAg5kpms74zcuLNI2OWZgGL4tp4snhmcscGEZ3D XezIF07n70XUMPtydITBlOgiSmH7kUA1tHomf56jZM6sTDIEO7Cyo8pj3B/3DePS0OdR 2CjhO/A4+gOLvz+aT/XTIBaag2eThCx/hphFJKDhsCd/TEO68XxQcUcPB/edOpMPWdGe cA== Received: from aserp3030.oracle.com (aserp3030.oracle.com [141.146.126.71]) by aserp2120.oracle.com with ESMTP id 33gp9mq688-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Fri, 18 Sep 2020 13:37:55 +0000 Received: from pps.filterd (aserp3030.oracle.com [127.0.0.1]) by aserp3030.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 08IDU8rb142507; Fri, 18 Sep 2020 13:35:55 GMT Received: from userv0121.oracle.com (userv0121.oracle.com [156.151.31.72]) by aserp3030.oracle.com with ESMTP id 33khppqf2h-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 18 Sep 2020 13:35:55 +0000 Received: from abhmp0009.oracle.com (abhmp0009.oracle.com [141.146.116.15]) by userv0121.oracle.com (8.14.4/8.13.8) with ESMTP id 08IDZqLf018486; Fri, 18 Sep 2020 13:35:52 GMT Received: from localhost.uk.oracle.com (/10.175.217.104) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Fri, 18 Sep 2020 13:35:52 +0000 From: Alan Maguire To: ast@kernel.org, daniel@iogearbox.net, andriin@fb.com, yhs@fb.com Cc: linux@rasmusvillemoes.dk, andriy.shevchenko@linux.intel.com, pmladek@suse.com, kafai@fb.com, songliubraving@fb.com, john.fastabend@gmail.com, kpsingh@chromium.org, shuah@kernel.org, rdna@fb.com, scott.branden@broadcom.com, quentin@isovalent.com, cneirabustos@gmail.com, jakub@cloudflare.com, mingo@redhat.com, rostedt@goodmis.org, bpf@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, acme@kernel.org, Alan Maguire Subject: [PATCH v5 bpf-next 4/6] selftests/bpf: add bpf_btf_snprintf helper tests Date: Fri, 18 Sep 2020 14:34:33 +0100 Message-Id: <1600436075-2961-5-git-send-email-alan.maguire@oracle.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1600436075-2961-1-git-send-email-alan.maguire@oracle.com> References: <1600436075-2961-1-git-send-email-alan.maguire@oracle.com> X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9747 signatures=668679 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 malwarescore=0 suspectscore=0 mlxlogscore=999 phishscore=0 mlxscore=0 adultscore=0 spamscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2009180110 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9747 signatures=668679 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 bulkscore=0 mlxlogscore=999 adultscore=0 malwarescore=0 clxscore=1015 lowpriorityscore=0 phishscore=0 spamscore=0 priorityscore=1501 suspectscore=0 impostorscore=0 mlxscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2009180110 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Tests verifying snprintf()ing of various data structures, flags combinations using a tp_btf program. Signed-off-by: Alan Maguire --- .../selftests/bpf/prog_tests/btf_snprintf.c | 55 +++++ .../selftests/bpf/progs/netif_receive_skb.c | 260 +++++++++++++++++++++ 2 files changed, 315 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/btf_snprintf.c create mode 100644 tools/testing/selftests/bpf/progs/netif_receive_skb.c diff --git a/tools/testing/selftests/bpf/prog_tests/btf_snprintf.c b/tools/testing/selftests/bpf/prog_tests/btf_snprintf.c new file mode 100644 index 0000000..8f277a5 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/btf_snprintf.c @@ -0,0 +1,55 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include "netif_receive_skb.skel.h" + +/* Demonstrate that bpf_btf_snprintf succeeds with non-zero return values, + * and that string representation of kernel data can then be displayed + * via bpf_trace_printk(). + */ +void test_btf_snprintf(void) +{ + struct netif_receive_skb *skel; + struct netif_receive_skb__bss *bss; + int err, duration = 0; + + skel = netif_receive_skb__open(); + if (CHECK(!skel, "skel_open", "failed to open skeleton\n")) + return; + + err = netif_receive_skb__load(skel); + if (CHECK(err, "skel_load", "failed to load skeleton: %d\n", err)) + goto cleanup; + + bss = skel->bss; + + err = netif_receive_skb__attach(skel); + if (CHECK(err, "skel_attach", "skeleton attach failed: %d\n", err)) + goto cleanup; + + /* generate receive event */ + system("ping -c 1 127.0.0.1 > /dev/null"); + + /* + * Make sure netif_receive_skb program was triggered + * and it set expected return values from bpf_trace_printk()s + * and all tests ran. + */ + if (CHECK(bss->ret <= 0, + "bpf_btf_snprintf: got return value", + "ret <= 0 %ld test %d\n", bss->ret, bss->ran_subtests)) + goto cleanup; + + if (CHECK(bss->ran_subtests == 0, "check if subtests ran", + "no subtests ran, did BPF program run?")) + goto cleanup; + + if (CHECK(bss->num_subtests != bss->ran_subtests, + "check all subtests ran", + "only ran %d of %d tests\n", bss->num_subtests, + bss->ran_subtests)) + goto cleanup; + +cleanup: + netif_receive_skb__destroy(skel); +} diff --git a/tools/testing/selftests/bpf/progs/netif_receive_skb.c b/tools/testing/selftests/bpf/progs/netif_receive_skb.c new file mode 100644 index 0000000..dd08a7d --- /dev/null +++ b/tools/testing/selftests/bpf/progs/netif_receive_skb.c @@ -0,0 +1,260 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2020, Oracle and/or its affiliates. */ + +#include "vmlinux.h" +#include +#include +#include + +long ret = 0; +int num_subtests = 0; +int ran_subtests = 0; + +#define STRSIZE 2048 +#define EXPECTED_STRSIZE 256 + +#ifndef ARRAY_SIZE +#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) +#endif + +struct { + __uint(type, BPF_MAP_TYPE_PERCPU_ARRAY); + __uint(max_entries, 1); + __type(key, __u32); + __type(value, char[STRSIZE]); +} strdata SEC(".maps"); + +static int __strncmp(const void *m1, const void *m2, size_t len) +{ + const unsigned char *s1 = m1; + const unsigned char *s2 = m2; + int i, delta = 0; + +#pragma clang loop unroll(full) + for (i = 0; i < len; i++) { + delta = s1[i] - s2[i]; + if (delta || s1[i] == 0 || s2[i] == 0) + break; + } + return delta; +} + +/* Use __builtin_btf_type_id to test btf_snprintf by type id instead of name */ +#if __has_builtin(__builtin_btf_type_id) +#define TEST_BTF_BY_ID(_str, _typestr, _ptr, _hflags) \ + do { \ + int _expected_ret = ret; \ + _ptr.type = 0; \ + _ptr.type_id = __builtin_btf_type_id(_typestr, 0); \ + ret = bpf_btf_snprintf(_str, STRSIZE, &_ptr, \ + sizeof(_ptr), _hflags); \ + if (ret != _expected_ret) { \ + bpf_printk("expected ret (%d), got (%d)", \ + _expected_ret, ret); \ + ret = -EBADMSG; \ + } \ + } while (0) +#else +#define TEST_BTF_BY_ID(_str, _typestr, _ptr, _hflags) \ + do { } while (0) +#endif + +#define TEST_BTF(_str, _type, _flags, _expected, ...) \ + do { \ + static const char _expectedval[EXPECTED_STRSIZE] = \ + _expected; \ + static const char _ptrtype[64] = #_type; \ + __u64 _hflags = _flags | BTF_F_COMPACT; \ + static _type _ptrdata = __VA_ARGS__; \ + static struct btf_ptr _ptr = { }; \ + int _cmp; \ + \ + _ptr.type = _ptrtype; \ + _ptr.ptr = &_ptrdata; \ + \ + ++num_subtests; \ + if (ret < 0) \ + break; \ + ++ran_subtests; \ + ret = bpf_btf_snprintf(_str, STRSIZE, \ + &_ptr, sizeof(_ptr), _hflags); \ + if (ret) \ + break; \ + _cmp = __strncmp(_str, _expectedval, EXPECTED_STRSIZE); \ + if (_cmp != 0) { \ + bpf_printk("(%d) got %s", _cmp, _str); \ + bpf_printk("(%d) expected %s", _cmp, \ + _expectedval); \ + ret = -EBADMSG; \ + break; \ + } \ + TEST_BTF_BY_ID(_str, #_type, _ptr, _hflags); \ + } while (0) + +/* Use where expected data string matches its stringified declaration */ +#define TEST_BTF_C(_str, _type, _flags, ...) \ + TEST_BTF(_str, _type, _flags, "(" #_type ")" #__VA_ARGS__, \ + __VA_ARGS__) + +/* TRACE_EVENT(netif_receive_skb, + * TP_PROTO(struct sk_buff *skb), + */ +SEC("tp_btf/netif_receive_skb") +int BPF_PROG(trace_netif_receive_skb, struct sk_buff *skb) +{ + static __u64 flags[] = { 0, BTF_F_COMPACT, BTF_F_ZERO, BTF_F_PTR_RAW, + BTF_F_NONAME, BTF_F_COMPACT | BTF_F_ZERO | + BTF_F_PTR_RAW | BTF_F_NONAME }; + static const char skbtype[] = "struct sk_buff"; + static struct btf_ptr p = { }; + __u32 key = 0; + int i, __ret; + char *str; + + str = bpf_map_lookup_elem(&strdata, &key); + if (!str) + return 0; + + /* Ensure we can write skb string representation */ + p.type = skbtype; + p.ptr = skb; + for (i = 0; i < ARRAY_SIZE(flags); i++) { + ++num_subtests; + ret = bpf_btf_snprintf(str, STRSIZE, &p, sizeof(p), 0); + if (ret < 0) + bpf_printk("returned %d when writing skb", ret); + ++ran_subtests; + } + + /* Check invalid ptr value */ + p.ptr = 0; + __ret = bpf_btf_snprintf(str, STRSIZE, &p, sizeof(p), 0); + if (__ret >= 0) { + bpf_printk("printing NULL should generate error, got (%d)", + __ret); + ret = -ERANGE; + } + + /* Verify type display for various types. */ + + /* simple int */ + TEST_BTF_C(str, int, 0, 1234); + TEST_BTF(str, int, BTF_F_NONAME, "1234", 1234); + /* zero value should be printed at toplevel */ + TEST_BTF(str, int, 0, "(int)0", 0); + TEST_BTF(str, int, BTF_F_NONAME, "0", 0); + TEST_BTF(str, int, BTF_F_ZERO, "(int)0", 0); + TEST_BTF(str, int, BTF_F_NONAME | BTF_F_ZERO, "0", 0); + TEST_BTF_C(str, int, 0, -4567); + TEST_BTF(str, int, BTF_F_NONAME, "-4567", -4567); + + /* simple char */ + TEST_BTF_C(str, char, 0, 100); + TEST_BTF(str, char, BTF_F_NONAME, "100", 100); + /* zero value should be printed at toplevel */ + TEST_BTF(str, char, 0, "(char)0", 0); + TEST_BTF(str, char, BTF_F_NONAME, "0", 0); + TEST_BTF(str, char, BTF_F_ZERO, "(char)0", 0); + TEST_BTF(str, char, BTF_F_NONAME | BTF_F_ZERO, "0", 0); + + /* simple typedef */ + TEST_BTF_C(str, uint64_t, 0, 100); + TEST_BTF(str, u64, BTF_F_NONAME, "1", 1); + /* zero value should be printed at toplevel */ + TEST_BTF(str, u64, 0, "(u64)0", 0); + TEST_BTF(str, u64, BTF_F_NONAME, "0", 0); + TEST_BTF(str, u64, BTF_F_ZERO, "(u64)0", 0); + TEST_BTF(str, u64, BTF_F_NONAME|BTF_F_ZERO, "0", 0); + + /* typedef struct */ + TEST_BTF_C(str, atomic_t, 0, {.counter = (int)1,}); + TEST_BTF(str, atomic_t, BTF_F_NONAME, "{1,}", {.counter = 1,}); + /* typedef with 0 value should be printed at toplevel */ + TEST_BTF(str, atomic_t, 0, "(atomic_t){}", {.counter = 0,}); + TEST_BTF(str, atomic_t, BTF_F_NONAME, "{}", {.counter = 0,}); + TEST_BTF(str, atomic_t, BTF_F_ZERO, "(atomic_t){.counter = (int)0,}", + {.counter = 0,}); + TEST_BTF(str, atomic_t, BTF_F_NONAME|BTF_F_ZERO, + "{0,}", {.counter = 0,}); + + /* enum where enum value does (and does not) exist */ + TEST_BTF_C(str, enum bpf_cmd, 0, BPF_MAP_CREATE); + TEST_BTF(str, enum bpf_cmd, 0, "(enum bpf_cmd)BPF_MAP_CREATE", 0); + TEST_BTF(str, enum bpf_cmd, BTF_F_NONAME, "BPF_MAP_CREATE", + BPF_MAP_CREATE); + TEST_BTF(str, enum bpf_cmd, BTF_F_NONAME|BTF_F_ZERO, + "BPF_MAP_CREATE", 0); + + TEST_BTF(str, enum bpf_cmd, BTF_F_ZERO, "(enum bpf_cmd)BPF_MAP_CREATE", + BPF_MAP_CREATE); + TEST_BTF(str, enum bpf_cmd, BTF_F_NONAME|BTF_F_ZERO, + "BPF_MAP_CREATE", BPF_MAP_CREATE); + TEST_BTF_C(str, enum bpf_cmd, 0, 2000); + TEST_BTF(str, enum bpf_cmd, BTF_F_NONAME, "2000", 2000); + + /* simple struct */ + TEST_BTF_C(str, struct btf_enum, 0, + {.name_off = (__u32)3,.val = (__s32)-1,}); + TEST_BTF(str, struct btf_enum, BTF_F_NONAME, "{3,-1,}", + { .name_off = 3, .val = -1,}); + TEST_BTF(str, struct btf_enum, BTF_F_NONAME, "{-1,}", + { .name_off = 0, .val = -1,}); + TEST_BTF(str, struct btf_enum, BTF_F_NONAME|BTF_F_ZERO, "{0,-1,}", + { .name_off = 0, .val = -1,}); + /* empty struct should be printed */ + TEST_BTF(str, struct btf_enum, 0, "(struct btf_enum){}", + { .name_off = 0, .val = 0,}); + TEST_BTF(str, struct btf_enum, BTF_F_NONAME, "{}", + { .name_off = 0, .val = 0,}); + TEST_BTF(str, struct btf_enum, BTF_F_ZERO, + "(struct btf_enum){.name_off = (__u32)0,.val = (__s32)0,}", + { .name_off = 0, .val = 0,}); + + /* struct with pointers */ + TEST_BTF(str, struct list_head, BTF_F_PTR_RAW, + "(struct list_head){.next = (struct list_head *)0x0000000000000001,}", + { .next = (struct list_head *)1 }); + /* NULL pointer should not be displayed */ + TEST_BTF(str, struct list_head, BTF_F_PTR_RAW, + "(struct list_head){}", + { .next = (struct list_head *)0 }); + + /* struct with char array */ + TEST_BTF(str, struct bpf_prog_info, 0, + "(struct bpf_prog_info){.name = (char[])['f','o','o',],}", + { .name = "foo",}); + TEST_BTF(str, struct bpf_prog_info, BTF_F_NONAME, + "{['f','o','o',],}", + {.name = "foo",}); + /* leading null char means do not display string */ + TEST_BTF(str, struct bpf_prog_info, 0, + "(struct bpf_prog_info){}", + {.name = {'\0', 'f', 'o', 'o'}}); + /* handle non-printable characters */ + TEST_BTF(str, struct bpf_prog_info, 0, + "(struct bpf_prog_info){.name = (char[])[1,2,3,],}", + { .name = {1, 2, 3, 0}}); + + /* struct with non-char array */ + TEST_BTF(str, struct __sk_buff, 0, + "(struct __sk_buff){.cb = (__u32[])[1,2,3,4,5,],}", + { .cb = {1, 2, 3, 4, 5,},}); + TEST_BTF(str, struct __sk_buff, BTF_F_NONAME, + "{[1,2,3,4,5,],}", + { .cb = { 1, 2, 3, 4, 5},}); + /* For non-char, arrays, show non-zero values only */ + TEST_BTF(str, struct __sk_buff, 0, + "(struct __sk_buff){.cb = (__u32[])[1,],}", + { .cb = { 0, 0, 1, 0, 0},}); + + /* struct with bitfields */ + TEST_BTF_C(str, struct bpf_insn, 0, + {.code = (__u8)1,.dst_reg = (__u8)0x2,.src_reg = (__u8)0x3,.off = (__s16)4,.imm = (__s32)5,}); + TEST_BTF(str, struct bpf_insn, BTF_F_NONAME, "{1,0x2,0x3,4,5,}", + {.code = 1, .dst_reg = 0x2, .src_reg = 0x3, .off = 4, + .imm = 5,}); + + return 0; +} + +char _license[] SEC("license") = "GPL";