// 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(off=0,imm=0) 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(off=0,imm=0) 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(); }