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/cdefs.h> 33 __FBSDID("$FreeBSD$"); 34 35 #include <sys/param.h> 36 #include <sys/ioctl.h> 37 #include <sys/kcov.h> 38 #include <sys/mman.h> 39 40 #include <machine/atomic.h> 41 42 #include <fcntl.h> 43 #include <pthread.h> 44 #include <semaphore.h> 45 46 #include <atf-c.h> 47 48 static const char *modes[] = { 49 "PC tracing", 50 "comparison tracing", 51 }; 52 53 static int 54 open_kcov(void) 55 { 56 int fd; 57 58 fd = open("/dev/kcov", O_RDWR); 59 if (fd == -1) 60 atf_tc_skip("Failed to open /dev/kcov"); 61 62 return (fd); 63 } 64 65 ATF_TC_WITHOUT_HEAD(kcov_bufsize); 66 ATF_TC_BODY(kcov_bufsize, tc) 67 { 68 int fd; 69 70 fd = open_kcov(); 71 72 ATF_CHECK(ioctl(fd, KIOSETBUFSIZE, 0) == -1); 73 ATF_CHECK(ioctl(fd, KIOSETBUFSIZE, 1) == -1); 74 ATF_CHECK(ioctl(fd, KIOSETBUFSIZE, 2) == 0); 75 ATF_CHECK(ioctl(fd, KIOSETBUFSIZE, 2) == -1); 76 77 close(fd); 78 } 79 80 ATF_TC_WITHOUT_HEAD(kcov_mmap); 81 ATF_TC_BODY(kcov_mmap, tc) 82 { 83 void *data1, *data2; 84 int fd; 85 86 fd = open_kcov(); 87 88 ATF_CHECK(mmap(NULL, PAGE_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, 89 fd, 0) == MAP_FAILED); 90 91 ATF_REQUIRE(ioctl(fd, KIOSETBUFSIZE, 92 2 * PAGE_SIZE / KCOV_ENTRY_SIZE) == 0); 93 94 ATF_CHECK(mmap(NULL, PAGE_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, 95 fd, 0) == MAP_FAILED); 96 ATF_CHECK(mmap(NULL, 3 * PAGE_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, 97 fd, 0) == MAP_FAILED); 98 ATF_REQUIRE((data1 = mmap(NULL, 2 * PAGE_SIZE, PROT_READ | PROT_WRITE, 99 MAP_SHARED, fd, 0)) != MAP_FAILED); 100 ATF_REQUIRE((data2 = mmap(NULL, 2 * PAGE_SIZE, PROT_READ | PROT_WRITE, 101 MAP_SHARED, fd, 0)) != MAP_FAILED); 102 103 *(uint64_t *)data1 = 0x123456789abcdeful; 104 ATF_REQUIRE(*(uint64_t *)data2 == 0x123456789abcdefull); 105 *(uint64_t *)data2 = 0xfedcba9876543210ul; 106 ATF_REQUIRE(*(uint64_t *)data1 == 0xfedcba9876543210ull); 107 108 munmap(data1, 2 * PAGE_SIZE); 109 munmap(data2, 2 * PAGE_SIZE); 110 111 close(fd); 112 } 113 114 /* This shouldn't panic */ 115 ATF_TC_WITHOUT_HEAD(kcov_mmap_no_munmap); 116 ATF_TC_BODY(kcov_mmap_no_munmap, tc) 117 { 118 int fd; 119 120 fd = open_kcov(); 121 122 ATF_REQUIRE(ioctl(fd, KIOSETBUFSIZE, PAGE_SIZE / KCOV_ENTRY_SIZE) == 0); 123 124 ATF_CHECK(mmap(NULL, PAGE_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, 125 fd, 0) != MAP_FAILED); 126 127 close(fd); 128 } 129 130 ATF_TC_WITHOUT_HEAD(kcov_mmap_no_munmap_no_close); 131 ATF_TC_BODY(kcov_mmap_no_munmap_no_close, tc) 132 { 133 int fd; 134 135 fd = open_kcov(); 136 137 ATF_REQUIRE(ioctl(fd, KIOSETBUFSIZE, PAGE_SIZE / KCOV_ENTRY_SIZE) == 0); 138 139 ATF_CHECK(mmap(NULL, PAGE_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, 140 fd, 0) != MAP_FAILED); 141 } 142 143 static sem_t sem1, sem2; 144 145 static void * 146 kcov_mmap_enable_thread(void *data) 147 { 148 int fd; 149 150 fd = open_kcov(); 151 *(int *)data = fd; 152 153 ATF_REQUIRE(ioctl(fd, KIOSETBUFSIZE, PAGE_SIZE / KCOV_ENTRY_SIZE) == 0); 154 ATF_CHECK(mmap(NULL, PAGE_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, 155 fd, 0) != MAP_FAILED); 156 ATF_CHECK(ioctl(fd, KIOENABLE, KCOV_MODE_TRACE_PC) == 0); 157 158 sem_post(&sem1); 159 sem_wait(&sem2); 160 161 return (NULL); 162 } 163 164 ATF_TC_WITHOUT_HEAD(kcov_mmap_enable_thread_close); 165 ATF_TC_BODY(kcov_mmap_enable_thread_close, tc) 166 { 167 pthread_t thread; 168 int fd; 169 170 sem_init(&sem1, 0, 0); 171 sem_init(&sem2, 0, 0); 172 pthread_create(&thread, NULL, 173 kcov_mmap_enable_thread, &fd); 174 sem_wait(&sem1); 175 close(fd); 176 sem_post(&sem2); 177 pthread_join(thread, NULL); 178 } 179 180 ATF_TC_WITHOUT_HEAD(kcov_enable); 181 ATF_TC_BODY(kcov_enable, tc) 182 { 183 int fd; 184 185 fd = open_kcov(); 186 187 ATF_CHECK(ioctl(fd, KIOENABLE, KCOV_MODE_TRACE_PC) == -1); 188 189 ATF_REQUIRE(ioctl(fd, KIOSETBUFSIZE, PAGE_SIZE / KCOV_ENTRY_SIZE) == 0); 190 191 /* We need to enable before disable */ 192 ATF_CHECK(ioctl(fd, KIODISABLE, 0) == -1); 193 194 /* Check enabling works only with a valid trace method */ 195 ATF_CHECK(ioctl(fd, KIOENABLE, -1) == -1); 196 ATF_CHECK(ioctl(fd, KIOENABLE, KCOV_MODE_TRACE_PC) == 0); 197 ATF_CHECK(ioctl(fd, KIOENABLE, KCOV_MODE_TRACE_PC) == -1); 198 ATF_CHECK(ioctl(fd, KIOENABLE, KCOV_MODE_TRACE_CMP) == -1); 199 200 /* Disable should only be called once */ 201 ATF_CHECK(ioctl(fd, KIODISABLE, 0) == 0); 202 ATF_CHECK(ioctl(fd, KIODISABLE, 0) == -1); 203 204 /* Re-enabling should also work */ 205 ATF_CHECK(ioctl(fd, KIOENABLE, KCOV_MODE_TRACE_CMP) == 0); 206 ATF_CHECK(ioctl(fd, KIODISABLE, 0) == 0); 207 208 close(fd); 209 } 210 211 ATF_TC_WITHOUT_HEAD(kcov_enable_no_disable); 212 ATF_TC_BODY(kcov_enable_no_disable, tc) 213 { 214 int fd; 215 216 fd = open_kcov(); 217 ATF_REQUIRE(ioctl(fd, KIOSETBUFSIZE, PAGE_SIZE / KCOV_ENTRY_SIZE) == 0); 218 ATF_CHECK(ioctl(fd, KIOENABLE, KCOV_MODE_TRACE_PC) == 0); 219 close(fd); 220 } 221 222 ATF_TC_WITHOUT_HEAD(kcov_enable_no_disable_no_close); 223 ATF_TC_BODY(kcov_enable_no_disable_no_close, tc) 224 { 225 int fd; 226 227 fd = open_kcov(); 228 ATF_REQUIRE(ioctl(fd, KIOSETBUFSIZE, PAGE_SIZE / KCOV_ENTRY_SIZE) == 0); 229 ATF_CHECK(ioctl(fd, KIOENABLE, KCOV_MODE_TRACE_PC) == 0); 230 } 231 232 static void * 233 common_head(int *fdp) 234 { 235 void *data; 236 int fd; 237 238 fd = open_kcov(); 239 240 ATF_REQUIRE_MSG(ioctl(fd, KIOSETBUFSIZE, 241 PAGE_SIZE / KCOV_ENTRY_SIZE) == 0, 242 "Unable to set the kcov buffer size"); 243 244 data = mmap(NULL, PAGE_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0); 245 ATF_REQUIRE_MSG(data != MAP_FAILED, "Unable to mmap the kcov buffer"); 246 247 *fdp = fd; 248 return (data); 249 } 250 251 static void 252 common_tail(int fd, void *data) 253 { 254 255 ATF_REQUIRE_MSG(munmap(data, PAGE_SIZE) == 0, 256 "Unable to unmap the kcov buffer"); 257 258 close(fd); 259 } 260 261 static void 262 basic_test(u_int mode) 263 { 264 uint64_t *buf; 265 int fd; 266 267 buf = common_head(&fd); 268 ATF_REQUIRE_MSG(ioctl(fd, KIOENABLE, mode) == 0, 269 "Unable to enable kcov %s", 270 mode < nitems(modes) ? modes[mode] : "unknown mode"); 271 272 atomic_store_64(&buf[0], 0); 273 274 sleep(0); 275 ATF_REQUIRE_MSG(atomic_load_64(&buf[0]) != 0, "No records found"); 276 277 ATF_REQUIRE_MSG(ioctl(fd, KIODISABLE, 0) == 0, 278 "Unable to disable kcov"); 279 280 common_tail(fd, buf); 281 } 282 283 ATF_TC_WITHOUT_HEAD(kcov_basic_pc); 284 ATF_TC_BODY(kcov_basic_pc, tc) 285 { 286 basic_test(KCOV_MODE_TRACE_PC); 287 } 288 289 ATF_TC_WITHOUT_HEAD(kcov_basic_cmp); 290 ATF_TC_BODY(kcov_basic_cmp, tc) 291 { 292 basic_test(KCOV_MODE_TRACE_CMP); 293 } 294 295 static void * 296 thread_test_helper(void *ptr) 297 { 298 uint64_t *buf = ptr; 299 300 atomic_store_64(&buf[0], 0); 301 sleep(0); 302 ATF_REQUIRE_MSG(atomic_load_64(&buf[0]) == 0, 303 "Records changed in blocked thread"); 304 305 return (NULL); 306 } 307 308 static void 309 thread_test(u_int mode) 310 { 311 pthread_t thread; 312 uint64_t *buf; 313 int fd; 314 315 buf = common_head(&fd); 316 317 ATF_REQUIRE_MSG(ioctl(fd, KIOENABLE, mode) == 0, 318 "Unable to enable kcov %s", 319 mode < nitems(modes) ? modes[mode] : "unknown mode"); 320 321 pthread_create(&thread, NULL, thread_test_helper, buf); 322 pthread_join(thread, NULL); 323 324 ATF_REQUIRE_MSG(ioctl(fd, KIODISABLE, 0) == 0, 325 "Unable to disable kcov"); 326 327 common_tail(fd, buf); 328 } 329 330 ATF_TC_WITHOUT_HEAD(kcov_thread_pc); 331 ATF_TC_BODY(kcov_thread_pc, tc) 332 { 333 thread_test(KCOV_MODE_TRACE_PC); 334 } 335 336 ATF_TC_WITHOUT_HEAD(kcov_thread_cmp); 337 ATF_TC_BODY(kcov_thread_cmp, tc) 338 { 339 thread_test(KCOV_MODE_TRACE_CMP); 340 } 341 342 struct multi_thread_data { 343 char *buf; 344 int fd; 345 u_int mode; 346 int thread; 347 }; 348 349 static void * 350 multi_thread_test_helper(void *ptr) 351 { 352 struct multi_thread_data *data = ptr; 353 354 ATF_REQUIRE_MSG(ioctl(data->fd, KIOENABLE, data->mode) == 0, 355 "Unable to enable kcov %s in thread %d", 356 data->mode < nitems(modes) ? modes[data->mode] : "unknown mode", 357 data->thread); 358 359 atomic_store_64(&data->buf[0], 0); 360 sleep(0); 361 ATF_REQUIRE_MSG(atomic_load_64(&data->buf[0]) != 0, 362 "No records found in thread %d", data->thread); 363 364 return (NULL); 365 } 366 367 ATF_TC_WITHOUT_HEAD(kcov_enable_multi_thread); 368 ATF_TC_BODY(kcov_enable_multi_thread, t) 369 { 370 struct multi_thread_data data; 371 pthread_t thread; 372 373 data.buf = common_head(&data.fd); 374 375 /* Run the thread to completion */ 376 data.thread = 1; 377 data.mode = KCOV_MODE_TRACE_PC; 378 pthread_create(&thread, NULL, multi_thread_test_helper, &data); 379 pthread_join(thread, NULL); 380 381 /* Run it again to check enable works on the same fd */ 382 data.thread = 2; 383 data.mode = KCOV_MODE_TRACE_CMP; 384 pthread_create(&thread, NULL, multi_thread_test_helper, &data); 385 pthread_join(thread, NULL); 386 387 common_tail(data.fd, data.buf); 388 } 389 390 ATF_TP_ADD_TCS(tp) 391 { 392 393 ATF_TP_ADD_TC(tp, kcov_bufsize); 394 ATF_TP_ADD_TC(tp, kcov_mmap); 395 ATF_TP_ADD_TC(tp, kcov_mmap_no_munmap); 396 ATF_TP_ADD_TC(tp, kcov_mmap_no_munmap_no_close); 397 ATF_TP_ADD_TC(tp, kcov_enable); 398 ATF_TP_ADD_TC(tp, kcov_enable_no_disable); 399 ATF_TP_ADD_TC(tp, kcov_enable_no_disable_no_close); 400 ATF_TP_ADD_TC(tp, kcov_mmap_enable_thread_close); 401 ATF_TP_ADD_TC(tp, kcov_basic_pc); 402 ATF_TP_ADD_TC(tp, kcov_basic_cmp); 403 ATF_TP_ADD_TC(tp, kcov_thread_pc); 404 ATF_TP_ADD_TC(tp, kcov_thread_cmp); 405 ATF_TP_ADD_TC(tp, kcov_enable_multi_thread); 406 return (atf_no_error()); 407 } 408