tools/testing/selftests/bpf/prog_tests/log_buf.c - linux/kernel/git/gregkh/driver-core - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /* Copyright (c) 2021 Facebook */

 #include <test_progs.h>
 #include <bpf/btf.h>

 #include "test_log_buf.skel.h"

 static size_t libbpf_log_pos;
 static char libbpf_log_buf[1024 * 1024];
 static bool libbpf_log_error;

 static int libbpf_print_cb(enum libbpf_print_level level, const char *fmt, va_list args)
 {
 	int emitted_cnt;
 	size_t left_cnt;

 	left_cnt = sizeof(libbpf_log_buf) - libbpf_log_pos;
 	emitted_cnt = vsnprintf(libbpf_log_buf + libbpf_log_pos, left_cnt, fmt, args);

 	if (emitted_cnt < 0 || emitted_cnt + 1 > left_cnt) {
 		libbpf_log_error = true;
 		return 0;
 	}

 	libbpf_log_pos += emitted_cnt;
 	return 0;
 }

 static void obj_load_log_buf(void)
 {
 	libbpf_print_fn_t old_print_cb = libbpf_set_print(libbpf_print_cb);
 	LIBBPF_OPTS(bpf_object_open_opts, opts);
 	const size_t log_buf_sz = 1024 * 1024;
 	struct test_log_buf* skel;
 	char *obj_log_buf, *good_log_buf, *bad_log_buf;
 	int err;

 	obj_log_buf = malloc(3 * log_buf_sz);
 	if (!ASSERT_OK_PTR(obj_log_buf, "obj_log_buf"))
 		return;

 	good_log_buf = obj_log_buf + log_buf_sz;
 	bad_log_buf = obj_log_buf + 2 * log_buf_sz;
 	obj_log_buf[0] = good_log_buf[0] = bad_log_buf[0] = '\0';

 	opts.kernel_log_buf = obj_log_buf;
 	opts.kernel_log_size = log_buf_sz;
 	opts.kernel_log_level = 4; /* for BTF this will turn into 1 */

 	/* In the first round every prog has its own log_buf, so libbpf logs
 	 * don't have program failure logs
 	 */
 	skel = test_log_buf__open_opts(&opts);
 	if (!ASSERT_OK_PTR(skel, "skel_open"))
 		goto cleanup;

 	/* set very verbose level for good_prog so we always get detailed logs */
 	bpf_program__set_log_buf(skel->progs.good_prog, good_log_buf, log_buf_sz);
 	bpf_program__set_log_level(skel->progs.good_prog, 2);

 	bpf_program__set_log_buf(skel->progs.bad_prog, bad_log_buf, log_buf_sz);
 	/* log_level 0 with custom log_buf means that verbose logs are not
 	 * requested if program load is successful, but libbpf should retry
 	 * with log_level 1 on error and put program's verbose load log into
 	 * custom log_buf
 	 */
 	bpf_program__set_log_level(skel->progs.bad_prog, 0);

 	err = test_log_buf__load(skel);
 	if (!ASSERT_ERR(err, "unexpected_load_success"))
 		goto cleanup;

 	ASSERT_FALSE(libbpf_log_error, "libbpf_log_error");

 	/* there should be no prog loading log because we specified per-prog log buf */
 	ASSERT_NULL(strstr(libbpf_log_buf, "-- BEGIN PROG LOAD LOG --"), "unexp_libbpf_log");
 	ASSERT_OK_PTR(strstr(libbpf_log_buf, "prog 'bad_prog': BPF program load failed"),
 		      "libbpf_log_not_empty");
 	ASSERT_OK_PTR(strstr(obj_log_buf, "DATASEC license"), "obj_log_not_empty");
 	ASSERT_OK_PTR(strstr(good_log_buf, "0: R1=ctx() R10=fp0"),
 		      "good_log_verbose");
 	ASSERT_OK_PTR(strstr(bad_log_buf, "invalid access to map value, value_size=16 off=16000 size=4"),
 		      "bad_log_not_empty");

 	if (env.verbosity > VERBOSE_NONE) {
 		printf("LIBBPF LOG:   \n=================\n%s=================\n", libbpf_log_buf);
 		printf("OBJ LOG:      \n=================\n%s=================\n", obj_log_buf);
 		printf("GOOD_PROG LOG:\n=================\n%s=================\n", good_log_buf);
 		printf("BAD_PROG  LOG:\n=================\n%s=================\n", bad_log_buf);
 	}

 	/* reset everything */
 	test_log_buf__destroy(skel);
 	obj_log_buf[0] = good_log_buf[0] = bad_log_buf[0] = '\0';
 	libbpf_log_buf[0] = '\0';
 	libbpf_log_pos = 0;
 	libbpf_log_error = false;

 	/* In the second round we let bad_prog's failure be logged through print callback */
 	opts.kernel_log_buf = NULL; /* let everything through into print callback */
 	opts.kernel_log_size = 0;
 	opts.kernel_log_level = 1;

 	skel = test_log_buf__open_opts(&opts);
 	if (!ASSERT_OK_PTR(skel, "skel_open"))
 		goto cleanup;

 	/* set normal verbose level for good_prog to check log_level is taken into account */
 	bpf_program__set_log_buf(skel->progs.good_prog, good_log_buf, log_buf_sz);
 	bpf_program__set_log_level(skel->progs.good_prog, 1);

 	err = test_log_buf__load(skel);
 	if (!ASSERT_ERR(err, "unexpected_load_success"))
 		goto cleanup;

 	ASSERT_FALSE(libbpf_log_error, "libbpf_log_error");

 	/* this time prog loading error should be logged through print callback */
 	ASSERT_OK_PTR(strstr(libbpf_log_buf, "libbpf: prog 'bad_prog': -- BEGIN PROG LOAD LOG --"),
 		      "libbpf_log_correct");
 	ASSERT_STREQ(obj_log_buf, "", "obj_log__empty");
 	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",
 		     "good_log_ok");
 	ASSERT_STREQ(bad_log_buf, "", "bad_log_empty");

 	if (env.verbosity > VERBOSE_NONE) {
 		printf("LIBBPF LOG:   \n=================\n%s=================\n", libbpf_log_buf);
 		printf("OBJ LOG:      \n=================\n%s=================\n", obj_log_buf);
 		printf("GOOD_PROG LOG:\n=================\n%s=================\n", good_log_buf);
 		printf("BAD_PROG  LOG:\n=================\n%s=================\n", bad_log_buf);
 	}

 cleanup:
 	free(obj_log_buf);
 	test_log_buf__destroy(skel);
 	libbpf_set_print(old_print_cb);
 }

 static void bpf_prog_load_log_buf(void)
 {
 	const struct bpf_insn good_prog_insns[] = {
 		BPF_MOV64_IMM(BPF_REG_0, 0),
 		BPF_EXIT_INSN(),
 	};
 	const size_t good_prog_insn_cnt = sizeof(good_prog_insns) / sizeof(struct bpf_insn);
 	const struct bpf_insn bad_prog_insns[] = {
 		BPF_EXIT_INSN(),
 	};
 	size_t bad_prog_insn_cnt = sizeof(bad_prog_insns) / sizeof(struct bpf_insn);
 	LIBBPF_OPTS(bpf_prog_load_opts, opts);
 	const size_t log_buf_sz = 1024 * 1024;
 	char *log_buf;
 	int fd = -1;

 	log_buf = malloc(log_buf_sz);
 	if (!ASSERT_OK_PTR(log_buf, "log_buf_alloc"))
 		return;
 	opts.log_buf = log_buf;
 	opts.log_size = log_buf_sz;

 	/* with log_level == 0 log_buf shoud stay empty for good prog */
 	log_buf[0] = '\0';
 	opts.log_level = 0;
 	fd = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, "good_prog", "GPL",
 			   good_prog_insns, good_prog_insn_cnt, &opts);
 	ASSERT_STREQ(log_buf, "", "good_log_0");
 	ASSERT_GE(fd, 0, "good_fd1");
 	if (fd >= 0)
 		close(fd);
 	fd = -1;

 	/* log_level == 2 should always fill log_buf, even for good prog */
 	log_buf[0] = '\0';
 	opts.log_level = 2;
 	fd = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, "good_prog", "GPL",
 			   good_prog_insns, good_prog_insn_cnt, &opts);
 	ASSERT_OK_PTR(strstr(log_buf, "0: R1=ctx() R10=fp0"), "good_log_2");
 	ASSERT_GE(fd, 0, "good_fd2");
 	if (fd >= 0)
 		close(fd);
 	fd = -1;

 	/* log_level == 0 should fill log_buf for bad prog */
 	log_buf[0] = '\0';
 	opts.log_level = 0;
 	fd = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, "bad_prog", "GPL",
 			   bad_prog_insns, bad_prog_insn_cnt, &opts);
 	ASSERT_OK_PTR(strstr(log_buf, "R0 !read_ok"), "bad_log_0");
 	ASSERT_LT(fd, 0, "bad_fd");
 	if (fd >= 0)
 		close(fd);
 	fd = -1;

 	free(log_buf);
 }

 static void bpf_btf_load_log_buf(void)
 {
 	LIBBPF_OPTS(bpf_btf_load_opts, opts);
 	const size_t log_buf_sz = 1024 * 1024;
 	const void *raw_btf_data;
 	__u32 raw_btf_size;
 	struct btf *btf;
 	char *log_buf = NULL;
 	int fd = -1;

 	btf = btf__new_empty();
 	if (!ASSERT_OK_PTR(btf, "empty_btf"))
 		return;

 	ASSERT_GT(btf__add_int(btf, "int", 4, 0), 0, "int_type");

 	raw_btf_data = btf__raw_data(btf, &raw_btf_size);
 	if (!ASSERT_OK_PTR(raw_btf_data, "raw_btf_data_good"))
 		goto cleanup;

 	log_buf = malloc(log_buf_sz);
 	if (!ASSERT_OK_PTR(log_buf, "log_buf_alloc"))
 		goto cleanup;
 	opts.log_buf = log_buf;
 	opts.log_size = log_buf_sz;

 	/* with log_level == 0 log_buf shoud stay empty for good BTF */
 	log_buf[0] = '\0';
 	opts.log_level = 0;
 	fd = bpf_btf_load(raw_btf_data, raw_btf_size, &opts);
 	ASSERT_STREQ(log_buf, "", "good_log_0");
 	ASSERT_GE(fd, 0, "good_fd1");
 	if (fd >= 0)
 		close(fd);
 	fd = -1;

 	/* log_level == 2 should always fill log_buf, even for good BTF */
 	log_buf[0] = '\0';
 	opts.log_level = 2;
 	fd = bpf_btf_load(raw_btf_data, raw_btf_size, &opts);
 	printf("LOG_BUF: %s\n", log_buf);
 	ASSERT_OK_PTR(strstr(log_buf, "magic: 0xeb9f"), "good_log_2");
 	ASSERT_GE(fd, 0, "good_fd2");
 	if (fd >= 0)
 		close(fd);
 	fd = -1;

 	/* make BTF bad, add pointer pointing to non-existing type */
 	ASSERT_GT(btf__add_ptr(btf, 100), 0, "bad_ptr_type");

 	raw_btf_data = btf__raw_data(btf, &raw_btf_size);
 	if (!ASSERT_OK_PTR(raw_btf_data, "raw_btf_data_bad"))
 		goto cleanup;

 	/* log_level == 0 should fill log_buf for bad BTF */
 	log_buf[0] = '\0';
 	opts.log_level = 0;
 	fd = bpf_btf_load(raw_btf_data, raw_btf_size, &opts);
 	printf("LOG_BUF: %s\n", log_buf);
 	ASSERT_OK_PTR(strstr(log_buf, "[2] PTR (anon) type_id=100 Invalid type_id"), "bad_log_0");
 	ASSERT_LT(fd, 0, "bad_fd");
 	if (fd >= 0)
 		close(fd);
 	fd = -1;

 cleanup:
 	free(log_buf);
 	btf__free(btf);
 }

 void test_log_buf(void)
 {
 	if (test__start_subtest("obj_load_log_buf"))
 		obj_load_log_buf();
 	if (test__start_subtest("bpf_prog_load_log_buf"))
 		bpf_prog_load_log_buf();
 	if (test__start_subtest("bpf_btf_load_log_buf"))
 		bpf_btf_load_log_buf();
 }
	// SPDX-License-Identifier: GPL-2.0
	/* Copyright (c) 2021 Facebook */

	#include <test_progs.h>
	#include <bpf/btf.h>

	#include "test_log_buf.skel.h"

	static size_t libbpf_log_pos;
	static char libbpf_log_buf[1024 * 1024];
	static bool libbpf_log_error;

	static int libbpf_print_cb(enum libbpf_print_level level, const char *fmt, va_list args)
	{
	int emitted_cnt;
	size_t left_cnt;

	left_cnt = sizeof(libbpf_log_buf) - libbpf_log_pos;
	emitted_cnt = vsnprintf(libbpf_log_buf + libbpf_log_pos, left_cnt, fmt, args);

	if (emitted_cnt < 0 \|\| emitted_cnt + 1 > left_cnt) {
	libbpf_log_error = true;
	return 0;
	}

	libbpf_log_pos += emitted_cnt;
	return 0;
	}

	static void obj_load_log_buf(void)
	{
	libbpf_print_fn_t old_print_cb = libbpf_set_print(libbpf_print_cb);
	LIBBPF_OPTS(bpf_object_open_opts, opts);
	const size_t log_buf_sz = 1024 * 1024;
	struct test_log_buf* skel;
	char obj_log_buf, good_log_buf, *bad_log_buf;
	int err;

	obj_log_buf = malloc(3 * log_buf_sz);
	if (!ASSERT_OK_PTR(obj_log_buf, "obj_log_buf"))
	return;

	good_log_buf = obj_log_buf + log_buf_sz;
	bad_log_buf = obj_log_buf + 2 * log_buf_sz;
	obj_log_buf[0] = good_log_buf[0] = bad_log_buf[0] = '\0';

	opts.kernel_log_buf = obj_log_buf;
	opts.kernel_log_size = log_buf_sz;
	opts.kernel_log_level = 4; /* for BTF this will turn into 1 */

	/* In the first round every prog has its own log_buf, so libbpf logs
	* don't have program failure logs
	*/
	skel = test_log_buf__open_opts(&opts);
	if (!ASSERT_OK_PTR(skel, "skel_open"))
	goto cleanup;

	/* set very verbose level for good_prog so we always get detailed logs */
	bpf_program__set_log_buf(skel->progs.good_prog, good_log_buf, log_buf_sz);
	bpf_program__set_log_level(skel->progs.good_prog, 2);

	bpf_program__set_log_buf(skel->progs.bad_prog, bad_log_buf, log_buf_sz);
	/* log_level 0 with custom log_buf means that verbose logs are not
	* requested if program load is successful, but libbpf should retry
	* with log_level 1 on error and put program's verbose load log into
	* custom log_buf
	*/
	bpf_program__set_log_level(skel->progs.bad_prog, 0);

	err = test_log_buf__load(skel);
	if (!ASSERT_ERR(err, "unexpected_load_success"))
	goto cleanup;

	ASSERT_FALSE(libbpf_log_error, "libbpf_log_error");

	/* there should be no prog loading log because we specified per-prog log buf */
	ASSERT_NULL(strstr(libbpf_log_buf, "-- BEGIN PROG LOAD LOG --"), "unexp_libbpf_log");
	ASSERT_OK_PTR(strstr(libbpf_log_buf, "prog 'bad_prog': BPF program load failed"),
	"libbpf_log_not_empty");
	ASSERT_OK_PTR(strstr(obj_log_buf, "DATASEC license"), "obj_log_not_empty");
	ASSERT_OK_PTR(strstr(good_log_buf, "0: R1=ctx() R10=fp0"),
	"good_log_verbose");
	ASSERT_OK_PTR(strstr(bad_log_buf, "invalid access to map value, value_size=16 off=16000 size=4"),
	"bad_log_not_empty");

	if (env.verbosity > VERBOSE_NONE) {
	printf("LIBBPF LOG: \n=================\n%s=================\n", libbpf_log_buf);
	printf("OBJ LOG: \n=================\n%s=================\n", obj_log_buf);
	printf("GOOD_PROG LOG:\n=================\n%s=================\n", good_log_buf);
	printf("BAD_PROG LOG:\n=================\n%s=================\n", bad_log_buf);
	}

	/* reset everything */
	test_log_buf__destroy(skel);
	obj_log_buf[0] = good_log_buf[0] = bad_log_buf[0] = '\0';
	libbpf_log_buf[0] = '\0';
	libbpf_log_pos = 0;
	libbpf_log_error = false;

	/* In the second round we let bad_prog's failure be logged through print callback */
	opts.kernel_log_buf = NULL; /* let everything through into print callback */
	opts.kernel_log_size = 0;
	opts.kernel_log_level = 1;

	skel = test_log_buf__open_opts(&opts);
	if (!ASSERT_OK_PTR(skel, "skel_open"))
	goto cleanup;

	/* set normal verbose level for good_prog to check log_level is taken into account */
	bpf_program__set_log_buf(skel->progs.good_prog, good_log_buf, log_buf_sz);
	bpf_program__set_log_level(skel->progs.good_prog, 1);

	err = test_log_buf__load(skel);
	if (!ASSERT_ERR(err, "unexpected_load_success"))
	goto cleanup;

	ASSERT_FALSE(libbpf_log_error, "libbpf_log_error");

	/* this time prog loading error should be logged through print callback */
	ASSERT_OK_PTR(strstr(libbpf_log_buf, "libbpf: prog 'bad_prog': -- BEGIN PROG LOAD LOG --"),
	"libbpf_log_correct");
	ASSERT_STREQ(obj_log_buf, "", "obj_log__empty");
	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",
	"good_log_ok");
	ASSERT_STREQ(bad_log_buf, "", "bad_log_empty");

	if (env.verbosity > VERBOSE_NONE) {
	printf("LIBBPF LOG: \n=================\n%s=================\n", libbpf_log_buf);
	printf("OBJ LOG: \n=================\n%s=================\n", obj_log_buf);
	printf("GOOD_PROG LOG:\n=================\n%s=================\n", good_log_buf);
	printf("BAD_PROG LOG:\n=================\n%s=================\n", bad_log_buf);
	}

	cleanup:
	free(obj_log_buf);
	test_log_buf__destroy(skel);
	libbpf_set_print(old_print_cb);
	}

	static void bpf_prog_load_log_buf(void)
	{
	const struct bpf_insn good_prog_insns[] = {
	BPF_MOV64_IMM(BPF_REG_0, 0),
	BPF_EXIT_INSN(),
	};
	const size_t good_prog_insn_cnt = sizeof(good_prog_insns) / sizeof(struct bpf_insn);
	const struct bpf_insn bad_prog_insns[] = {
	BPF_EXIT_INSN(),
	};
	size_t bad_prog_insn_cnt = sizeof(bad_prog_insns) / sizeof(struct bpf_insn);
	LIBBPF_OPTS(bpf_prog_load_opts, opts);
	const size_t log_buf_sz = 1024 * 1024;
	char *log_buf;
	int fd = -1;

	log_buf = malloc(log_buf_sz);
	if (!ASSERT_OK_PTR(log_buf, "log_buf_alloc"))
	return;
	opts.log_buf = log_buf;
	opts.log_size = log_buf_sz;

	/* with log_level == 0 log_buf shoud stay empty for good prog */
	log_buf[0] = '\0';
	opts.log_level = 0;
	fd = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, "good_prog", "GPL",
	good_prog_insns, good_prog_insn_cnt, &opts);
	ASSERT_STREQ(log_buf, "", "good_log_0");
	ASSERT_GE(fd, 0, "good_fd1");
	if (fd >= 0)
	close(fd);
	fd = -1;

	/* log_level == 2 should always fill log_buf, even for good prog */
	log_buf[0] = '\0';
	opts.log_level = 2;
	fd = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, "good_prog", "GPL",
	good_prog_insns, good_prog_insn_cnt, &opts);
	ASSERT_OK_PTR(strstr(log_buf, "0: R1=ctx() R10=fp0"), "good_log_2");
	ASSERT_GE(fd, 0, "good_fd2");
	if (fd >= 0)
	close(fd);
	fd = -1;

	/* log_level == 0 should fill log_buf for bad prog */
	log_buf[0] = '\0';
	opts.log_level = 0;
	fd = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, "bad_prog", "GPL",
	bad_prog_insns, bad_prog_insn_cnt, &opts);
	ASSERT_OK_PTR(strstr(log_buf, "R0 !read_ok"), "bad_log_0");
	ASSERT_LT(fd, 0, "bad_fd");
	if (fd >= 0)
	close(fd);
	fd = -1;

	free(log_buf);
	}

	static void bpf_btf_load_log_buf(void)
	{
	LIBBPF_OPTS(bpf_btf_load_opts, opts);
	const size_t log_buf_sz = 1024 * 1024;
	const void *raw_btf_data;
	__u32 raw_btf_size;
	struct btf *btf;
	char *log_buf = NULL;
	int fd = -1;

	btf = btf__new_empty();
	if (!ASSERT_OK_PTR(btf, "empty_btf"))
	return;

	ASSERT_GT(btf__add_int(btf, "int", 4, 0), 0, "int_type");

	raw_btf_data = btf__raw_data(btf, &raw_btf_size);
	if (!ASSERT_OK_PTR(raw_btf_data, "raw_btf_data_good"))
	goto cleanup;

	log_buf = malloc(log_buf_sz);
	if (!ASSERT_OK_PTR(log_buf, "log_buf_alloc"))
	goto cleanup;
	opts.log_buf = log_buf;
	opts.log_size = log_buf_sz;

	/* with log_level == 0 log_buf shoud stay empty for good BTF */
	log_buf[0] = '\0';
	opts.log_level = 0;
	fd = bpf_btf_load(raw_btf_data, raw_btf_size, &opts);
	ASSERT_STREQ(log_buf, "", "good_log_0");
	ASSERT_GE(fd, 0, "good_fd1");
	if (fd >= 0)
	close(fd);
	fd = -1;

	/* log_level == 2 should always fill log_buf, even for good BTF */
	log_buf[0] = '\0';
	opts.log_level = 2;
	fd = bpf_btf_load(raw_btf_data, raw_btf_size, &opts);
	printf("LOG_BUF: %s\n", log_buf);
	ASSERT_OK_PTR(strstr(log_buf, "magic: 0xeb9f"), "good_log_2");
	ASSERT_GE(fd, 0, "good_fd2");
	if (fd >= 0)
	close(fd);
	fd = -1;

	/* make BTF bad, add pointer pointing to non-existing type */
	ASSERT_GT(btf__add_ptr(btf, 100), 0, "bad_ptr_type");

	raw_btf_data = btf__raw_data(btf, &raw_btf_size);
	if (!ASSERT_OK_PTR(raw_btf_data, "raw_btf_data_bad"))
	goto cleanup;

	/* log_level == 0 should fill log_buf for bad BTF */
	log_buf[0] = '\0';
	opts.log_level = 0;
	fd = bpf_btf_load(raw_btf_data, raw_btf_size, &opts);
	printf("LOG_BUF: %s\n", log_buf);
	ASSERT_OK_PTR(strstr(log_buf, "[2] PTR (anon) type_id=100 Invalid type_id"), "bad_log_0");
	ASSERT_LT(fd, 0, "bad_fd");
	if (fd >= 0)
	close(fd);
	fd = -1;

	cleanup:
	free(log_buf);
	btf__free(btf);
	}

	void test_log_buf(void)
	{
	if (test__start_subtest("obj_load_log_buf"))
	obj_load_log_buf();
	if (test__start_subtest("bpf_prog_load_log_buf"))
	bpf_prog_load_log_buf();
	if (test__start_subtest("bpf_btf_load_log_buf"))
	bpf_btf_load_log_buf();
	}