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