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