1// SPDX-License-Identifier: GPL-2.0
2/* Copyright (c) 2021 Facebook */
3
4#include <test_progs.h>
5#include <bpf/btf.h>
6
7#include "test_log_buf.skel.h"
8
9static size_t libbpf_log_pos;
10static char libbpf_log_buf[1024 * 1024];
11static bool libbpf_log_error;
12
13static int libbpf_print_cb(enum libbpf_print_level level, const char *fmt, va_list args)
14{
15	int emitted_cnt;
16	size_t left_cnt;
17
18	left_cnt = sizeof(libbpf_log_buf) - libbpf_log_pos;
19	emitted_cnt = vsnprintf(libbpf_log_buf + libbpf_log_pos, left_cnt, fmt, args);
20
21	if (emitted_cnt < 0 || emitted_cnt + 1 > left_cnt) {
22		libbpf_log_error = true;
23		return 0;
24	}
25
26	libbpf_log_pos += emitted_cnt;
27	return 0;
28}
29
30static void obj_load_log_buf(void)
31{
32	libbpf_print_fn_t old_print_cb = libbpf_set_print(libbpf_print_cb);
33	LIBBPF_OPTS(bpf_object_open_opts, opts);
34	const size_t log_buf_sz = 1024 * 1024;
35	struct test_log_buf* skel;
36	char *obj_log_buf, *good_log_buf, *bad_log_buf;
37	int err;
38
39	obj_log_buf = malloc(3 * log_buf_sz);
40	if (!ASSERT_OK_PTR(obj_log_buf, "obj_log_buf"))
41		return;
42
43	good_log_buf = obj_log_buf + log_buf_sz;
44	bad_log_buf = obj_log_buf + 2 * log_buf_sz;
45	obj_log_buf[0] = good_log_buf[0] = bad_log_buf[0] = '\0';
46
47	opts.kernel_log_buf = obj_log_buf;
48	opts.kernel_log_size = log_buf_sz;
49	opts.kernel_log_level = 4; /* for BTF this will turn into 1 */
50
51	/* In the first round every prog has its own log_buf, so libbpf logs
52	 * don't have program failure logs
53	 */
54	skel = test_log_buf__open_opts(&opts);
55	if (!ASSERT_OK_PTR(skel, "skel_open"))
56		goto cleanup;
57
58	/* set very verbose level for good_prog so we always get detailed logs */
59	bpf_program__set_log_buf(skel->progs.good_prog, good_log_buf, log_buf_sz);
60	bpf_program__set_log_level(skel->progs.good_prog, 2);
61
62	bpf_program__set_log_buf(skel->progs.bad_prog, bad_log_buf, log_buf_sz);
63	/* log_level 0 with custom log_buf means that verbose logs are not
64	 * requested if program load is successful, but libbpf should retry
65	 * with log_level 1 on error and put program's verbose load log into
66	 * custom log_buf
67	 */
68	bpf_program__set_log_level(skel->progs.bad_prog, 0);
69
70	err = test_log_buf__load(skel);
71	if (!ASSERT_ERR(err, "unexpected_load_success"))
72		goto cleanup;
73
74	ASSERT_FALSE(libbpf_log_error, "libbpf_log_error");
75
76	/* there should be no prog loading log because we specified per-prog log buf */
77	ASSERT_NULL(strstr(libbpf_log_buf, "-- BEGIN PROG LOAD LOG --"), "unexp_libbpf_log");
78	ASSERT_OK_PTR(strstr(libbpf_log_buf, "prog 'bad_prog': BPF program load failed"),
79		      "libbpf_log_not_empty");
80	ASSERT_OK_PTR(strstr(obj_log_buf, "DATASEC license"), "obj_log_not_empty");
81	ASSERT_OK_PTR(strstr(good_log_buf, "0: R1=ctx() R10=fp0"),
82		      "good_log_verbose");
83	ASSERT_OK_PTR(strstr(bad_log_buf, "invalid access to map value, value_size=16 off=16000 size=4"),
84		      "bad_log_not_empty");
85
86	if (env.verbosity > VERBOSE_NONE) {
87		printf("LIBBPF LOG:   \n=================\n%s=================\n", libbpf_log_buf);
88		printf("OBJ LOG:      \n=================\n%s=================\n", obj_log_buf);
89		printf("GOOD_PROG LOG:\n=================\n%s=================\n", good_log_buf);
90		printf("BAD_PROG  LOG:\n=================\n%s=================\n", bad_log_buf);
91	}
92
93	/* reset everything */
94	test_log_buf__destroy(skel);
95	obj_log_buf[0] = good_log_buf[0] = bad_log_buf[0] = '\0';
96	libbpf_log_buf[0] = '\0';
97	libbpf_log_pos = 0;
98	libbpf_log_error = false;
99
100	/* In the second round we let bad_prog's failure be logged through print callback */
101	opts.kernel_log_buf = NULL; /* let everything through into print callback */
102	opts.kernel_log_size = 0;
103	opts.kernel_log_level = 1;
104
105	skel = test_log_buf__open_opts(&opts);
106	if (!ASSERT_OK_PTR(skel, "skel_open"))
107		goto cleanup;
108
109	/* set normal verbose level for good_prog to check log_level is taken into account */
110	bpf_program__set_log_buf(skel->progs.good_prog, good_log_buf, log_buf_sz);
111	bpf_program__set_log_level(skel->progs.good_prog, 1);
112
113	err = test_log_buf__load(skel);
114	if (!ASSERT_ERR(err, "unexpected_load_success"))
115		goto cleanup;
116
117	ASSERT_FALSE(libbpf_log_error, "libbpf_log_error");
118
119	/* this time prog loading error should be logged through print callback */
120	ASSERT_OK_PTR(strstr(libbpf_log_buf, "libbpf: prog 'bad_prog': -- BEGIN PROG LOAD LOG --"),
121		      "libbpf_log_correct");
122	ASSERT_STREQ(obj_log_buf, "", "obj_log__empty");
123	ASSERT_STREQ(good_log_buf, "processed 4 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0\n",
124		     "good_log_ok");
125	ASSERT_STREQ(bad_log_buf, "", "bad_log_empty");
126
127	if (env.verbosity > VERBOSE_NONE) {
128		printf("LIBBPF LOG:   \n=================\n%s=================\n", libbpf_log_buf);
129		printf("OBJ LOG:      \n=================\n%s=================\n", obj_log_buf);
130		printf("GOOD_PROG LOG:\n=================\n%s=================\n", good_log_buf);
131		printf("BAD_PROG  LOG:\n=================\n%s=================\n", bad_log_buf);
132	}
133
134cleanup:
135	free(obj_log_buf);
136	test_log_buf__destroy(skel);
137	libbpf_set_print(old_print_cb);
138}
139
140static void bpf_prog_load_log_buf(void)
141{
142	const struct bpf_insn good_prog_insns[] = {
143		BPF_MOV64_IMM(BPF_REG_0, 0),
144		BPF_EXIT_INSN(),
145	};
146	const size_t good_prog_insn_cnt = sizeof(good_prog_insns) / sizeof(struct bpf_insn);
147	const struct bpf_insn bad_prog_insns[] = {
148		BPF_EXIT_INSN(),
149	};
150	size_t bad_prog_insn_cnt = sizeof(bad_prog_insns) / sizeof(struct bpf_insn);
151	LIBBPF_OPTS(bpf_prog_load_opts, opts);
152	const size_t log_buf_sz = 1024 * 1024;
153	char *log_buf;
154	int fd = -1;
155
156	log_buf = malloc(log_buf_sz);
157	if (!ASSERT_OK_PTR(log_buf, "log_buf_alloc"))
158		return;
159	opts.log_buf = log_buf;
160	opts.log_size = log_buf_sz;
161
162	/* with log_level == 0 log_buf shoud stay empty for good prog */
163	log_buf[0] = '\0';
164	opts.log_level = 0;
165	fd = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, "good_prog", "GPL",
166			   good_prog_insns, good_prog_insn_cnt, &opts);
167	ASSERT_STREQ(log_buf, "", "good_log_0");
168	ASSERT_GE(fd, 0, "good_fd1");
169	if (fd >= 0)
170		close(fd);
171	fd = -1;
172
173	/* log_level == 2 should always fill log_buf, even for good prog */
174	log_buf[0] = '\0';
175	opts.log_level = 2;
176	fd = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, "good_prog", "GPL",
177			   good_prog_insns, good_prog_insn_cnt, &opts);
178	ASSERT_OK_PTR(strstr(log_buf, "0: R1=ctx() R10=fp0"), "good_log_2");
179	ASSERT_GE(fd, 0, "good_fd2");
180	if (fd >= 0)
181		close(fd);
182	fd = -1;
183
184	/* log_level == 0 should fill log_buf for bad prog */
185	log_buf[0] = '\0';
186	opts.log_level = 0;
187	fd = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, "bad_prog", "GPL",
188			   bad_prog_insns, bad_prog_insn_cnt, &opts);
189	ASSERT_OK_PTR(strstr(log_buf, "R0 !read_ok"), "bad_log_0");
190	ASSERT_LT(fd, 0, "bad_fd");
191	if (fd >= 0)
192		close(fd);
193	fd = -1;
194
195	free(log_buf);
196}
197
198static void bpf_btf_load_log_buf(void)
199{
200	LIBBPF_OPTS(bpf_btf_load_opts, opts);
201	const size_t log_buf_sz = 1024 * 1024;
202	const void *raw_btf_data;
203	__u32 raw_btf_size;
204	struct btf *btf;
205	char *log_buf = NULL;
206	int fd = -1;
207
208	btf = btf__new_empty();
209	if (!ASSERT_OK_PTR(btf, "empty_btf"))
210		return;
211
212	ASSERT_GT(btf__add_int(btf, "int", 4, 0), 0, "int_type");
213
214	raw_btf_data = btf__raw_data(btf, &raw_btf_size);
215	if (!ASSERT_OK_PTR(raw_btf_data, "raw_btf_data_good"))
216		goto cleanup;
217
218	log_buf = malloc(log_buf_sz);
219	if (!ASSERT_OK_PTR(log_buf, "log_buf_alloc"))
220		goto cleanup;
221	opts.log_buf = log_buf;
222	opts.log_size = log_buf_sz;
223
224	/* with log_level == 0 log_buf shoud stay empty for good BTF */
225	log_buf[0] = '\0';
226	opts.log_level = 0;
227	fd = bpf_btf_load(raw_btf_data, raw_btf_size, &opts);
228	ASSERT_STREQ(log_buf, "", "good_log_0");
229	ASSERT_GE(fd, 0, "good_fd1");
230	if (fd >= 0)
231		close(fd);
232	fd = -1;
233
234	/* log_level == 2 should always fill log_buf, even for good BTF */
235	log_buf[0] = '\0';
236	opts.log_level = 2;
237	fd = bpf_btf_load(raw_btf_data, raw_btf_size, &opts);
238	printf("LOG_BUF: %s\n", log_buf);
239	ASSERT_OK_PTR(strstr(log_buf, "magic: 0xeb9f"), "good_log_2");
240	ASSERT_GE(fd, 0, "good_fd2");
241	if (fd >= 0)
242		close(fd);
243	fd = -1;
244
245	/* make BTF bad, add pointer pointing to non-existing type */
246	ASSERT_GT(btf__add_ptr(btf, 100), 0, "bad_ptr_type");
247
248	raw_btf_data = btf__raw_data(btf, &raw_btf_size);
249	if (!ASSERT_OK_PTR(raw_btf_data, "raw_btf_data_bad"))
250		goto cleanup;
251
252	/* log_level == 0 should fill log_buf for bad BTF */
253	log_buf[0] = '\0';
254	opts.log_level = 0;
255	fd = bpf_btf_load(raw_btf_data, raw_btf_size, &opts);
256	printf("LOG_BUF: %s\n", log_buf);
257	ASSERT_OK_PTR(strstr(log_buf, "[2] PTR (anon) type_id=100 Invalid type_id"), "bad_log_0");
258	ASSERT_LT(fd, 0, "bad_fd");
259	if (fd >= 0)
260		close(fd);
261	fd = -1;
262
263cleanup:
264	free(log_buf);
265	btf__free(btf);
266}
267
268void test_log_buf(void)
269{
270	if (test__start_subtest("obj_load_log_buf"))
271		obj_load_log_buf();
272	if (test__start_subtest("bpf_prog_load_log_buf"))
273		bpf_prog_load_log_buf();
274	if (test__start_subtest("bpf_btf_load_log_buf"))
275		bpf_btf_load_log_buf();
276}
277