1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2018, 2019 Andrew Turner 5 * 6 * This software was developed by SRI International and the University of 7 * Cambridge Computer Laboratory under DARPA/AFRL contract FA8750-10-C-0237 8 * ("CTSRD"), as part of the DARPA CRASH research programme. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/param.h> 33 #include <sys/ioctl.h> 34 #include <sys/kcov.h> 35 #include <sys/mman.h> 36 37 #include <machine/atomic.h> 38 39 #include <fcntl.h> 40 #include <pthread.h> 41 #include <semaphore.h> 42 43 #include <atf-c.h> 44 45 static const char *modes[] = { 46 "PC tracing", 47 "comparison tracing", 48 }; 49 50 static size_t page_size; 51 52 static void 53 init_page_size(void) 54 { 55 page_size = getpagesize(); 56 } 57 58 static int 59 open_kcov(void) 60 { 61 int fd; 62 63 fd = open("/dev/kcov", O_RDWR); 64 if (fd == -1) 65 atf_tc_skip("Failed to open /dev/kcov"); 66 67 return (fd); 68 } 69 70 ATF_TC(kcov_bufsize); 71 ATF_TC_HEAD(kcov_bufsize, tc) 72 { 73 init_page_size(); 74 } 75 76 ATF_TC_BODY(kcov_bufsize, tc) 77 { 78 int fd; 79 80 fd = open_kcov(); 81 82 ATF_CHECK(ioctl(fd, KIOSETBUFSIZE, 0) == -1); 83 ATF_CHECK(ioctl(fd, KIOSETBUFSIZE, 1) == -1); 84 ATF_CHECK(ioctl(fd, KIOSETBUFSIZE, 2) == 0); 85 ATF_CHECK(ioctl(fd, KIOSETBUFSIZE, 2) == -1); 86 87 close(fd); 88 } 89 90 ATF_TC(kcov_mmap); 91 ATF_TC_HEAD(kcov_mmap, tc) 92 { 93 init_page_size(); 94 } 95 96 ATF_TC_BODY(kcov_mmap, tc) 97 { 98 void *data1, *data2; 99 int fd; 100 101 fd = open_kcov(); 102 103 ATF_CHECK(mmap(NULL, page_size, PROT_READ | PROT_WRITE, MAP_SHARED, 104 fd, 0) == MAP_FAILED); 105 106 ATF_REQUIRE(ioctl(fd, KIOSETBUFSIZE, 107 2 * page_size / KCOV_ENTRY_SIZE) == 0); 108 109 ATF_CHECK(mmap(NULL, page_size, PROT_READ | PROT_WRITE, MAP_SHARED, 110 fd, 0) == MAP_FAILED); 111 ATF_CHECK(mmap(NULL, 3 * page_size, PROT_READ | PROT_WRITE, MAP_SHARED, 112 fd, 0) == MAP_FAILED); 113 ATF_REQUIRE((data1 = mmap(NULL, 2 * page_size, PROT_READ | PROT_WRITE, 114 MAP_SHARED, fd, 0)) != MAP_FAILED); 115 ATF_REQUIRE((data2 = mmap(NULL, 2 * page_size, PROT_READ | PROT_WRITE, 116 MAP_SHARED, fd, 0)) != MAP_FAILED); 117 118 *(uint64_t *)data1 = 0x123456789abcdeful; 119 ATF_REQUIRE(*(uint64_t *)data2 == 0x123456789abcdefull); 120 *(uint64_t *)data2 = 0xfedcba9876543210ul; 121 ATF_REQUIRE(*(uint64_t *)data1 == 0xfedcba9876543210ull); 122 123 munmap(data1, 2 * page_size); 124 munmap(data2, 2 * page_size); 125 126 close(fd); 127 } 128 129 /* This shouldn't panic */ 130 ATF_TC(kcov_mmap_no_munmap); 131 ATF_TC_HEAD(kcov_mmap_no_munmap, tc) 132 { 133 init_page_size(); 134 } 135 136 ATF_TC_BODY(kcov_mmap_no_munmap, tc) 137 { 138 int fd; 139 140 fd = open_kcov(); 141 142 ATF_REQUIRE(ioctl(fd, KIOSETBUFSIZE, page_size / KCOV_ENTRY_SIZE) == 0); 143 144 ATF_CHECK(mmap(NULL, page_size, PROT_READ | PROT_WRITE, MAP_SHARED, 145 fd, 0) != MAP_FAILED); 146 147 close(fd); 148 } 149 150 ATF_TC(kcov_mmap_no_munmap_no_close); 151 ATF_TC_HEAD(kcov_mmap_no_munmap_no_close, tc) 152 { 153 init_page_size(); 154 } 155 156 ATF_TC_BODY(kcov_mmap_no_munmap_no_close, tc) 157 { 158 int fd; 159 160 fd = open_kcov(); 161 162 ATF_REQUIRE(ioctl(fd, KIOSETBUFSIZE, page_size / KCOV_ENTRY_SIZE) == 0); 163 164 ATF_CHECK(mmap(NULL, page_size, PROT_READ | PROT_WRITE, MAP_SHARED, 165 fd, 0) != MAP_FAILED); 166 } 167 168 static sem_t sem1, sem2; 169 170 static void * 171 kcov_mmap_enable_thread(void *data) 172 { 173 int fd; 174 175 fd = open_kcov(); 176 *(int *)data = fd; 177 178 ATF_REQUIRE(ioctl(fd, KIOSETBUFSIZE, page_size / KCOV_ENTRY_SIZE) == 0); 179 ATF_CHECK(mmap(NULL, page_size, PROT_READ | PROT_WRITE, MAP_SHARED, 180 fd, 0) != MAP_FAILED); 181 ATF_CHECK(ioctl(fd, KIOENABLE, KCOV_MODE_TRACE_PC) == 0); 182 183 sem_post(&sem1); 184 sem_wait(&sem2); 185 186 return (NULL); 187 } 188 189 ATF_TC(kcov_mmap_enable_thread_close); 190 ATF_TC_HEAD(kcov_mmap_enable_thread_close, tc) 191 { 192 init_page_size(); 193 } 194 195 ATF_TC_BODY(kcov_mmap_enable_thread_close, tc) 196 { 197 pthread_t thread; 198 int fd; 199 200 sem_init(&sem1, 0, 0); 201 sem_init(&sem2, 0, 0); 202 pthread_create(&thread, NULL, 203 kcov_mmap_enable_thread, &fd); 204 sem_wait(&sem1); 205 close(fd); 206 sem_post(&sem2); 207 pthread_join(thread, NULL); 208 } 209 210 ATF_TC(kcov_enable); 211 ATF_TC_HEAD(kcov_enable, tc) 212 { 213 init_page_size(); 214 } 215 216 ATF_TC_BODY(kcov_enable, tc) 217 { 218 int fd; 219 220 fd = open_kcov(); 221 222 ATF_CHECK(ioctl(fd, KIOENABLE, KCOV_MODE_TRACE_PC) == -1); 223 224 ATF_REQUIRE(ioctl(fd, KIOSETBUFSIZE, page_size / KCOV_ENTRY_SIZE) == 0); 225 226 /* We need to enable before disable */ 227 ATF_CHECK(ioctl(fd, KIODISABLE, 0) == -1); 228 229 /* Check enabling works only with a valid trace method */ 230 ATF_CHECK(ioctl(fd, KIOENABLE, -1) == -1); 231 ATF_CHECK(ioctl(fd, KIOENABLE, KCOV_MODE_TRACE_PC) == 0); 232 ATF_CHECK(ioctl(fd, KIOENABLE, KCOV_MODE_TRACE_PC) == -1); 233 ATF_CHECK(ioctl(fd, KIOENABLE, KCOV_MODE_TRACE_CMP) == -1); 234 235 /* Disable should only be called once */ 236 ATF_CHECK(ioctl(fd, KIODISABLE, 0) == 0); 237 ATF_CHECK(ioctl(fd, KIODISABLE, 0) == -1); 238 239 /* Re-enabling should also work */ 240 ATF_CHECK(ioctl(fd, KIOENABLE, KCOV_MODE_TRACE_CMP) == 0); 241 ATF_CHECK(ioctl(fd, KIODISABLE, 0) == 0); 242 243 close(fd); 244 } 245 246 ATF_TC(kcov_enable_no_disable); 247 ATF_TC_HEAD(kcov_enable_no_disable, tc) 248 { 249 init_page_size(); 250 } 251 252 ATF_TC_BODY(kcov_enable_no_disable, tc) 253 { 254 int fd; 255 256 fd = open_kcov(); 257 ATF_REQUIRE(ioctl(fd, KIOSETBUFSIZE, page_size / KCOV_ENTRY_SIZE) == 0); 258 ATF_CHECK(ioctl(fd, KIOENABLE, KCOV_MODE_TRACE_PC) == 0); 259 close(fd); 260 } 261 262 ATF_TC(kcov_enable_no_disable_no_close); 263 ATF_TC_HEAD(kcov_enable_no_disable_no_close, tc) 264 { 265 init_page_size(); 266 } 267 268 ATF_TC_BODY(kcov_enable_no_disable_no_close, tc) 269 { 270 int fd; 271 272 fd = open_kcov(); 273 ATF_REQUIRE(ioctl(fd, KIOSETBUFSIZE, page_size / KCOV_ENTRY_SIZE) == 0); 274 ATF_CHECK(ioctl(fd, KIOENABLE, KCOV_MODE_TRACE_PC) == 0); 275 } 276 277 static void * 278 common_head(int *fdp) 279 { 280 void *data; 281 int fd; 282 283 fd = open_kcov(); 284 285 ATF_REQUIRE_MSG(ioctl(fd, KIOSETBUFSIZE, 286 page_size / KCOV_ENTRY_SIZE) == 0, 287 "Unable to set the kcov buffer size"); 288 289 data = mmap(NULL, page_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0); 290 ATF_REQUIRE_MSG(data != MAP_FAILED, "Unable to mmap the kcov buffer"); 291 292 *fdp = fd; 293 return (data); 294 } 295 296 static void 297 common_tail(int fd, void *data) 298 { 299 300 ATF_REQUIRE_MSG(munmap(data, page_size) == 0, 301 "Unable to unmap the kcov buffer"); 302 303 close(fd); 304 } 305 306 static void 307 basic_test(u_int mode) 308 { 309 uint64_t *buf; 310 int fd; 311 312 buf = common_head(&fd); 313 ATF_REQUIRE_MSG(ioctl(fd, KIOENABLE, mode) == 0, 314 "Unable to enable kcov %s", 315 mode < nitems(modes) ? modes[mode] : "unknown mode"); 316 317 atomic_store_64(&buf[0], 0); 318 319 sleep(0); 320 ATF_REQUIRE_MSG(atomic_load_64(&buf[0]) != 0, "No records found"); 321 322 ATF_REQUIRE_MSG(ioctl(fd, KIODISABLE, 0) == 0, 323 "Unable to disable kcov"); 324 325 common_tail(fd, buf); 326 } 327 328 ATF_TC(kcov_basic_pc); 329 ATF_TC_HEAD(kcov_basic_pc, tc) 330 { 331 init_page_size(); 332 } 333 334 ATF_TC_BODY(kcov_basic_pc, tc) 335 { 336 basic_test(KCOV_MODE_TRACE_PC); 337 } 338 339 ATF_TC(kcov_basic_cmp); 340 ATF_TC_HEAD(kcov_basic_cmp, tc) 341 { 342 init_page_size(); 343 } 344 345 ATF_TC_BODY(kcov_basic_cmp, tc) 346 { 347 basic_test(KCOV_MODE_TRACE_CMP); 348 } 349 350 static void * 351 thread_test_helper(void *ptr) 352 { 353 uint64_t *buf = ptr; 354 355 atomic_store_64(&buf[0], 0); 356 sleep(0); 357 ATF_REQUIRE_MSG(atomic_load_64(&buf[0]) == 0, 358 "Records changed in blocked thread"); 359 360 return (NULL); 361 } 362 363 static void 364 thread_test(u_int mode) 365 { 366 pthread_t thread; 367 uint64_t *buf; 368 int fd; 369 370 buf = common_head(&fd); 371 372 ATF_REQUIRE_MSG(ioctl(fd, KIOENABLE, mode) == 0, 373 "Unable to enable kcov %s", 374 mode < nitems(modes) ? modes[mode] : "unknown mode"); 375 376 pthread_create(&thread, NULL, thread_test_helper, buf); 377 pthread_join(thread, NULL); 378 379 ATF_REQUIRE_MSG(ioctl(fd, KIODISABLE, 0) == 0, 380 "Unable to disable kcov"); 381 382 common_tail(fd, buf); 383 } 384 385 ATF_TC(kcov_thread_pc); 386 ATF_TC_HEAD(kcov_thread_pc, tc) 387 { 388 init_page_size(); 389 } 390 391 ATF_TC_BODY(kcov_thread_pc, tc) 392 { 393 thread_test(KCOV_MODE_TRACE_PC); 394 } 395 396 ATF_TC(kcov_thread_cmp); 397 ATF_TC_HEAD(kcov_thread_cmp, tc) 398 { 399 init_page_size(); 400 } 401 402 ATF_TC_BODY(kcov_thread_cmp, tc) 403 { 404 thread_test(KCOV_MODE_TRACE_CMP); 405 } 406 407 struct multi_thread_data { 408 uint64_t *buf; 409 int fd; 410 u_int mode; 411 int thread; 412 }; 413 414 static void * 415 multi_thread_test_helper(void *ptr) 416 { 417 struct multi_thread_data *data = ptr; 418 419 ATF_REQUIRE_MSG(ioctl(data->fd, KIOENABLE, data->mode) == 0, 420 "Unable to enable kcov %s in thread %d", 421 data->mode < nitems(modes) ? modes[data->mode] : "unknown mode", 422 data->thread); 423 424 atomic_store_64(&data->buf[0], 0); 425 sleep(0); 426 ATF_REQUIRE_MSG(atomic_load_64(&data->buf[0]) != 0, 427 "No records found in thread %d", data->thread); 428 429 return (NULL); 430 } 431 432 ATF_TC(kcov_enable_multi_thread); 433 ATF_TC_HEAD(kcov_enable_multi_thread, t) 434 { 435 init_page_size(); 436 } 437 438 ATF_TC_BODY(kcov_enable_multi_thread, t) 439 { 440 struct multi_thread_data data; 441 pthread_t thread; 442 443 data.buf = common_head(&data.fd); 444 445 /* Run the thread to completion */ 446 data.thread = 1; 447 data.mode = KCOV_MODE_TRACE_PC; 448 pthread_create(&thread, NULL, multi_thread_test_helper, &data); 449 pthread_join(thread, NULL); 450 451 /* Run it again to check enable works on the same fd */ 452 data.thread = 2; 453 data.mode = KCOV_MODE_TRACE_CMP; 454 pthread_create(&thread, NULL, multi_thread_test_helper, &data); 455 pthread_join(thread, NULL); 456 457 common_tail(data.fd, data.buf); 458 } 459 460 ATF_TP_ADD_TCS(tp) 461 { 462 463 ATF_TP_ADD_TC(tp, kcov_bufsize); 464 ATF_TP_ADD_TC(tp, kcov_mmap); 465 ATF_TP_ADD_TC(tp, kcov_mmap_no_munmap); 466 ATF_TP_ADD_TC(tp, kcov_mmap_no_munmap_no_close); 467 ATF_TP_ADD_TC(tp, kcov_enable); 468 ATF_TP_ADD_TC(tp, kcov_enable_no_disable); 469 ATF_TP_ADD_TC(tp, kcov_enable_no_disable_no_close); 470 ATF_TP_ADD_TC(tp, kcov_mmap_enable_thread_close); 471 ATF_TP_ADD_TC(tp, kcov_basic_pc); 472 ATF_TP_ADD_TC(tp, kcov_basic_cmp); 473 ATF_TP_ADD_TC(tp, kcov_thread_pc); 474 ATF_TP_ADD_TC(tp, kcov_thread_cmp); 475 ATF_TP_ADD_TC(tp, kcov_enable_multi_thread); 476 return (atf_no_error()); 477 } 478