1 /* 2 * Copyright (C) 2012 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include <stddef.h> 18 #include <stdbool.h> 19 #include <stdlib.h> 20 #include <signal.h> 21 #include <string.h> 22 #include <stdio.h> 23 #include <fcntl.h> 24 #include <errno.h> 25 #include <dirent.h> 26 #include <time.h> 27 #include <sys/ptrace.h> 28 #include <sys/stat.h> 29 30 #include <private/android_filesystem_config.h> 31 32 #include <cutils/logger.h> 33 #include <cutils/properties.h> 34 35 #include <corkscrew/demangle.h> 36 #include <corkscrew/backtrace.h> 37 38 #ifdef HAVE_SELINUX 39 #include <selinux/android.h> 40 #endif 41 42 #include "machine.h" 43 #include "tombstone.h" 44 #include "utility.h" 45 46 #define STACK_DEPTH 32 47 #define STACK_WORDS 16 48 49 #define MAX_TOMBSTONES 10 50 #define TOMBSTONE_DIR "/data/tombstones" 51 52 #define typecheck(x,y) { \ 53 typeof(x) __dummy1; \ 54 typeof(y) __dummy2; \ 55 (void)(&__dummy1 == &__dummy2); } 56 57 58 static bool signal_has_address(int sig) { 59 switch (sig) { 60 case SIGILL: 61 case SIGFPE: 62 case SIGSEGV: 63 case SIGBUS: 64 return true; 65 default: 66 return false; 67 } 68 } 69 70 static const char *get_signame(int sig) 71 { 72 switch(sig) { 73 case SIGILL: return "SIGILL"; 74 case SIGABRT: return "SIGABRT"; 75 case SIGBUS: return "SIGBUS"; 76 case SIGFPE: return "SIGFPE"; 77 case SIGSEGV: return "SIGSEGV"; 78 case SIGPIPE: return "SIGPIPE"; 79 #ifdef SIGSTKFLT 80 case SIGSTKFLT: return "SIGSTKFLT"; 81 #endif 82 case SIGSTOP: return "SIGSTOP"; 83 default: return "?"; 84 } 85 } 86 87 static const char *get_sigcode(int signo, int code) 88 { 89 switch (signo) { 90 case SIGILL: 91 switch (code) { 92 case ILL_ILLOPC: return "ILL_ILLOPC"; 93 case ILL_ILLOPN: return "ILL_ILLOPN"; 94 case ILL_ILLADR: return "ILL_ILLADR"; 95 case ILL_ILLTRP: return "ILL_ILLTRP"; 96 case ILL_PRVOPC: return "ILL_PRVOPC"; 97 case ILL_PRVREG: return "ILL_PRVREG"; 98 case ILL_COPROC: return "ILL_COPROC"; 99 case ILL_BADSTK: return "ILL_BADSTK"; 100 } 101 break; 102 case SIGBUS: 103 switch (code) { 104 case BUS_ADRALN: return "BUS_ADRALN"; 105 case BUS_ADRERR: return "BUS_ADRERR"; 106 case BUS_OBJERR: return "BUS_OBJERR"; 107 } 108 break; 109 case SIGFPE: 110 switch (code) { 111 case FPE_INTDIV: return "FPE_INTDIV"; 112 case FPE_INTOVF: return "FPE_INTOVF"; 113 case FPE_FLTDIV: return "FPE_FLTDIV"; 114 case FPE_FLTOVF: return "FPE_FLTOVF"; 115 case FPE_FLTUND: return "FPE_FLTUND"; 116 case FPE_FLTRES: return "FPE_FLTRES"; 117 case FPE_FLTINV: return "FPE_FLTINV"; 118 case FPE_FLTSUB: return "FPE_FLTSUB"; 119 } 120 break; 121 case SIGSEGV: 122 switch (code) { 123 case SEGV_MAPERR: return "SEGV_MAPERR"; 124 case SEGV_ACCERR: return "SEGV_ACCERR"; 125 } 126 break; 127 } 128 return "?"; 129 } 130 131 static void dump_revision_info(log_t* log) 132 { 133 char revision[PROPERTY_VALUE_MAX]; 134 135 property_get("ro.revision", revision, "unknown"); 136 137 _LOG(log, false, "Revision: '%s'\n", revision); 138 } 139 140 static void dump_build_info(log_t* log) 141 { 142 char fingerprint[PROPERTY_VALUE_MAX]; 143 144 property_get("ro.build.fingerprint", fingerprint, "unknown"); 145 146 _LOG(log, false, "Build fingerprint: '%s'\n", fingerprint); 147 } 148 149 static void dump_fault_addr(log_t* log, pid_t tid, int sig) 150 { 151 siginfo_t si; 152 153 memset(&si, 0, sizeof(si)); 154 if(ptrace(PTRACE_GETSIGINFO, tid, 0, &si)){ 155 _LOG(log, false, "cannot get siginfo: %s\n", strerror(errno)); 156 } else if (signal_has_address(sig)) { 157 _LOG(log, false, "signal %d (%s), code %d (%s), fault addr %08x\n", 158 sig, get_signame(sig), 159 si.si_code, get_sigcode(sig, si.si_code), 160 (uintptr_t) si.si_addr); 161 } else { 162 _LOG(log, false, "signal %d (%s), code %d (%s), fault addr --------\n", 163 sig, get_signame(sig), si.si_code, get_sigcode(sig, si.si_code)); 164 } 165 } 166 167 static void dump_thread_info(log_t* log, pid_t pid, pid_t tid, bool at_fault) { 168 char path[64]; 169 char threadnamebuf[1024]; 170 char* threadname = NULL; 171 FILE *fp; 172 173 snprintf(path, sizeof(path), "/proc/%d/comm", tid); 174 if ((fp = fopen(path, "r"))) { 175 threadname = fgets(threadnamebuf, sizeof(threadnamebuf), fp); 176 fclose(fp); 177 if (threadname) { 178 size_t len = strlen(threadname); 179 if (len && threadname[len - 1] == '\n') { 180 threadname[len - 1] = '\0'; 181 } 182 } 183 } 184 185 if (at_fault) { 186 char procnamebuf[1024]; 187 char* procname = NULL; 188 189 snprintf(path, sizeof(path), "/proc/%d/cmdline", pid); 190 if ((fp = fopen(path, "r"))) { 191 procname = fgets(procnamebuf, sizeof(procnamebuf), fp); 192 fclose(fp); 193 } 194 195 _LOG(log, false, "pid: %d, tid: %d, name: %s >>> %s <<<\n", pid, tid, 196 threadname ? threadname : "UNKNOWN", 197 procname ? procname : "UNKNOWN"); 198 } else { 199 _LOG(log, true, "pid: %d, tid: %d, name: %s\n", pid, tid, 200 threadname ? threadname : "UNKNOWN"); 201 } 202 } 203 204 static void dump_backtrace(const ptrace_context_t* context __attribute((unused)), 205 log_t* log, pid_t tid __attribute((unused)), bool at_fault, 206 const backtrace_frame_t* backtrace, size_t frames) { 207 _LOG(log, !at_fault, "\nbacktrace:\n"); 208 209 backtrace_symbol_t backtrace_symbols[STACK_DEPTH]; 210 get_backtrace_symbols_ptrace(context, backtrace, frames, backtrace_symbols); 211 for (size_t i = 0; i < frames; i++) { 212 char line[MAX_BACKTRACE_LINE_LENGTH]; 213 format_backtrace_line(i, &backtrace[i], &backtrace_symbols[i], 214 line, MAX_BACKTRACE_LINE_LENGTH); 215 _LOG(log, !at_fault, " %s\n", line); 216 } 217 free_backtrace_symbols(backtrace_symbols, frames); 218 } 219 220 static void dump_stack_segment(const ptrace_context_t* context, log_t* log, pid_t tid, 221 bool only_in_tombstone, uintptr_t* sp, size_t words, int label) { 222 for (size_t i = 0; i < words; i++) { 223 uint32_t stack_content; 224 if (!try_get_word_ptrace(tid, *sp, &stack_content)) { 225 break; 226 } 227 228 const map_info_t* mi; 229 const symbol_t* symbol; 230 find_symbol_ptrace(context, stack_content, &mi, &symbol); 231 232 if (symbol) { 233 char* demangled_name = demangle_symbol_name(symbol->name); 234 const char* symbol_name = demangled_name ? demangled_name : symbol->name; 235 uint32_t offset = stack_content - (mi->start + symbol->start); 236 if (!i && label >= 0) { 237 if (offset) { 238 _LOG(log, only_in_tombstone, " #%02d %08x %08x %s (%s+%u)\n", 239 label, *sp, stack_content, mi ? mi->name : "", symbol_name, offset); 240 } else { 241 _LOG(log, only_in_tombstone, " #%02d %08x %08x %s (%s)\n", 242 label, *sp, stack_content, mi ? mi->name : "", symbol_name); 243 } 244 } else { 245 if (offset) { 246 _LOG(log, only_in_tombstone, " %08x %08x %s (%s+%u)\n", 247 *sp, stack_content, mi ? mi->name : "", symbol_name, offset); 248 } else { 249 _LOG(log, only_in_tombstone, " %08x %08x %s (%s)\n", 250 *sp, stack_content, mi ? mi->name : "", symbol_name); 251 } 252 } 253 free(demangled_name); 254 } else { 255 if (!i && label >= 0) { 256 _LOG(log, only_in_tombstone, " #%02d %08x %08x %s\n", 257 label, *sp, stack_content, mi ? mi->name : ""); 258 } else { 259 _LOG(log, only_in_tombstone, " %08x %08x %s\n", 260 *sp, stack_content, mi ? mi->name : ""); 261 } 262 } 263 264 *sp += sizeof(uint32_t); 265 } 266 } 267 268 static void dump_stack(const ptrace_context_t* context, log_t* log, pid_t tid, bool at_fault, 269 const backtrace_frame_t* backtrace, size_t frames) { 270 bool have_first = false; 271 size_t first, last; 272 for (size_t i = 0; i < frames; i++) { 273 if (backtrace[i].stack_top) { 274 if (!have_first) { 275 have_first = true; 276 first = i; 277 } 278 last = i; 279 } 280 } 281 if (!have_first) { 282 return; 283 } 284 285 _LOG(log, !at_fault, "\nstack:\n"); 286 287 // Dump a few words before the first frame. 288 bool only_in_tombstone = !at_fault; 289 uintptr_t sp = backtrace[first].stack_top - STACK_WORDS * sizeof(uint32_t); 290 dump_stack_segment(context, log, tid, only_in_tombstone, &sp, STACK_WORDS, -1); 291 292 // Dump a few words from all successive frames. 293 // Only log the first 3 frames, put the rest in the tombstone. 294 for (size_t i = first; i <= last; i++) { 295 const backtrace_frame_t* frame = &backtrace[i]; 296 if (sp != frame->stack_top) { 297 _LOG(log, only_in_tombstone, " ........ ........\n"); 298 sp = frame->stack_top; 299 } 300 if (i - first == 3) { 301 only_in_tombstone = true; 302 } 303 if (i == last) { 304 dump_stack_segment(context, log, tid, only_in_tombstone, &sp, STACK_WORDS, i); 305 if (sp < frame->stack_top + frame->stack_size) { 306 _LOG(log, only_in_tombstone, " ........ ........\n"); 307 } 308 } else { 309 size_t words = frame->stack_size / sizeof(uint32_t); 310 if (words == 0) { 311 words = 1; 312 } else if (words > STACK_WORDS) { 313 words = STACK_WORDS; 314 } 315 dump_stack_segment(context, log, tid, only_in_tombstone, &sp, words, i); 316 } 317 } 318 } 319 320 static void dump_backtrace_and_stack(const ptrace_context_t* context, log_t* log, pid_t tid, 321 bool at_fault) { 322 backtrace_frame_t backtrace[STACK_DEPTH]; 323 ssize_t frames = unwind_backtrace_ptrace(tid, context, backtrace, 0, STACK_DEPTH); 324 if (frames > 0) { 325 dump_backtrace(context, log, tid, at_fault, backtrace, frames); 326 dump_stack(context, log, tid, at_fault, backtrace, frames); 327 } 328 } 329 330 static void dump_nearby_maps(const ptrace_context_t* context, log_t* log, pid_t tid) { 331 siginfo_t si; 332 memset(&si, 0, sizeof(si)); 333 if (ptrace(PTRACE_GETSIGINFO, tid, 0, &si)) { 334 _LOG(log, false, "cannot get siginfo for %d: %s\n", 335 tid, strerror(errno)); 336 return; 337 } 338 if (!signal_has_address(si.si_signo)) { 339 return; 340 } 341 342 uintptr_t addr = (uintptr_t) si.si_addr; 343 addr &= ~0xfff; /* round to 4K page boundary */ 344 if (addr == 0) { /* null-pointer deref */ 345 return; 346 } 347 348 _LOG(log, false, "\nmemory map around fault addr %08x:\n", (int)si.si_addr); 349 350 /* 351 * Search for a match, or for a hole where the match would be. The list 352 * is backward from the file content, so it starts at high addresses. 353 */ 354 map_info_t* map = context->map_info_list; 355 map_info_t *next = NULL; 356 map_info_t *prev = NULL; 357 while (map != NULL) { 358 if (addr >= map->start && addr < map->end) { 359 next = map->next; 360 break; 361 } else if (addr >= map->end) { 362 /* map would be between "prev" and this entry */ 363 next = map; 364 map = NULL; 365 break; 366 } 367 368 prev = map; 369 map = map->next; 370 } 371 372 /* 373 * Show "next" then "match" then "prev" so that the addresses appear in 374 * ascending order (like /proc/pid/maps). 375 */ 376 if (next != NULL) { 377 _LOG(log, false, " %08x-%08x %s\n", next->start, next->end, next->name); 378 } else { 379 _LOG(log, false, " (no map below)\n"); 380 } 381 if (map != NULL) { 382 _LOG(log, false, " %08x-%08x %s\n", map->start, map->end, map->name); 383 } else { 384 _LOG(log, false, " (no map for address)\n"); 385 } 386 if (prev != NULL) { 387 _LOG(log, false, " %08x-%08x %s\n", prev->start, prev->end, prev->name); 388 } else { 389 _LOG(log, false, " (no map above)\n"); 390 } 391 } 392 393 static void dump_thread(const ptrace_context_t* context, log_t* log, pid_t tid, bool at_fault, 394 int* total_sleep_time_usec) { 395 wait_for_stop(tid, total_sleep_time_usec); 396 397 dump_registers(context, log, tid, at_fault); 398 dump_backtrace_and_stack(context, log, tid, at_fault); 399 if (at_fault) { 400 dump_memory_and_code(context, log, tid, at_fault); 401 dump_nearby_maps(context, log, tid); 402 } 403 } 404 405 /* Return true if some thread is not detached cleanly */ 406 static bool dump_sibling_thread_report(const ptrace_context_t* context, 407 log_t* log, pid_t pid, pid_t tid, int* total_sleep_time_usec) { 408 char task_path[64]; 409 snprintf(task_path, sizeof(task_path), "/proc/%d/task", pid); 410 411 DIR* d = opendir(task_path); 412 /* Bail early if cannot open the task directory */ 413 if (d == NULL) { 414 XLOG("Cannot open /proc/%d/task\n", pid); 415 return false; 416 } 417 418 bool detach_failed = false; 419 struct dirent debuf; 420 struct dirent *de; 421 while (!readdir_r(d, &debuf, &de) && de) { 422 /* Ignore "." and ".." */ 423 if (!strcmp(de->d_name, ".") || !strcmp(de->d_name, "..")) { 424 continue; 425 } 426 427 /* The main thread at fault has been handled individually */ 428 char* end; 429 pid_t new_tid = strtoul(de->d_name, &end, 10); 430 if (*end || new_tid == tid) { 431 continue; 432 } 433 434 /* Skip this thread if cannot ptrace it */ 435 if (ptrace(PTRACE_ATTACH, new_tid, 0, 0) < 0) { 436 continue; 437 } 438 439 _LOG(log, true, "--- --- --- --- --- --- --- --- --- --- --- --- --- --- --- ---\n"); 440 dump_thread_info(log, pid, new_tid, false); 441 dump_thread(context, log, new_tid, false, total_sleep_time_usec); 442 443 if (ptrace(PTRACE_DETACH, new_tid, 0, 0) != 0) { 444 LOG("ptrace detach from %d failed: %s\n", new_tid, strerror(errno)); 445 detach_failed = true; 446 } 447 } 448 449 closedir(d); 450 return detach_failed; 451 } 452 453 /* 454 * Reads the contents of the specified log device, filters out the entries 455 * that don't match the specified pid, and writes them to the tombstone file. 456 * 457 * If "tailOnly" is set, we only print the last few lines. 458 */ 459 static void dump_log_file(log_t* log, pid_t pid, const char* filename, 460 bool tailOnly) 461 { 462 bool first = true; 463 464 /* circular buffer, for "tailOnly" mode */ 465 const int kShortLogMaxLines = 5; 466 const int kShortLogLineLen = 256; 467 char shortLog[kShortLogMaxLines][kShortLogLineLen]; 468 int shortLogCount = 0; 469 int shortLogNext = 0; 470 471 int logfd = open(filename, O_RDONLY | O_NONBLOCK); 472 if (logfd < 0) { 473 XLOG("Unable to open %s: %s\n", filename, strerror(errno)); 474 return; 475 } 476 477 union { 478 unsigned char buf[LOGGER_ENTRY_MAX_LEN + 1]; 479 struct logger_entry entry; 480 } log_entry; 481 482 while (true) { 483 ssize_t actual = read(logfd, log_entry.buf, LOGGER_ENTRY_MAX_LEN); 484 if (actual < 0) { 485 if (errno == EINTR) { 486 /* interrupted by signal, retry */ 487 continue; 488 } else if (errno == EAGAIN) { 489 /* non-blocking EOF; we're done */ 490 break; 491 } else { 492 _LOG(log, true, "Error while reading log: %s\n", 493 strerror(errno)); 494 break; 495 } 496 } else if (actual == 0) { 497 _LOG(log, true, "Got zero bytes while reading log: %s\n", 498 strerror(errno)); 499 break; 500 } 501 502 /* 503 * NOTE: if you XLOG something here, this will spin forever, 504 * because you will be writing as fast as you're reading. Any 505 * high-frequency debug diagnostics should just be written to 506 * the tombstone file. 507 */ 508 509 struct logger_entry* entry = &log_entry.entry; 510 511 if (entry->pid != (int32_t) pid) { 512 /* wrong pid, ignore */ 513 continue; 514 } 515 516 if (first) { 517 _LOG(log, true, "--------- %slog %s\n", 518 tailOnly ? "tail end of " : "", filename); 519 first = false; 520 } 521 522 /* 523 * Msg format is: <priority:1><tag:N>\0<message:N>\0 524 * 525 * We want to display it in the same format as "logcat -v threadtime" 526 * (although in this case the pid is redundant). 527 * 528 * TODO: scan for line breaks ('\n') and display each text line 529 * on a separate line, prefixed with the header, like logcat does. 530 */ 531 static const char* kPrioChars = "!.VDIWEFS"; 532 unsigned char prio = entry->msg[0]; 533 char* tag = entry->msg + 1; 534 char* msg = tag + strlen(tag) + 1; 535 536 /* consume any trailing newlines */ 537 char* eatnl = msg + strlen(msg) - 1; 538 while (eatnl >= msg && *eatnl == '\n') { 539 *eatnl-- = '\0'; 540 } 541 542 char prioChar = (prio < strlen(kPrioChars) ? kPrioChars[prio] : '?'); 543 544 char timeBuf[32]; 545 time_t sec = (time_t) entry->sec; 546 struct tm tmBuf; 547 struct tm* ptm; 548 ptm = localtime_r(&sec, &tmBuf); 549 strftime(timeBuf, sizeof(timeBuf), "%m-%d %H:%M:%S", ptm); 550 551 if (tailOnly) { 552 snprintf(shortLog[shortLogNext], kShortLogLineLen, 553 "%s.%03d %5d %5d %c %-8s: %s", 554 timeBuf, entry->nsec / 1000000, entry->pid, entry->tid, 555 prioChar, tag, msg); 556 shortLogNext = (shortLogNext + 1) % kShortLogMaxLines; 557 shortLogCount++; 558 } else { 559 _LOG(log, true, "%s.%03d %5d %5d %c %-8s: %s\n", 560 timeBuf, entry->nsec / 1000000, entry->pid, entry->tid, 561 prioChar, tag, msg); 562 } 563 } 564 565 if (tailOnly) { 566 int i; 567 568 /* 569 * If we filled the buffer, we want to start at "next", which has 570 * the oldest entry. If we didn't, we want to start at zero. 571 */ 572 if (shortLogCount < kShortLogMaxLines) { 573 shortLogNext = 0; 574 } else { 575 shortLogCount = kShortLogMaxLines; /* cap at window size */ 576 } 577 578 for (i = 0; i < shortLogCount; i++) { 579 _LOG(log, true, "%s\n", shortLog[shortLogNext]); 580 shortLogNext = (shortLogNext + 1) % kShortLogMaxLines; 581 } 582 } 583 584 close(logfd); 585 } 586 587 /* 588 * Dumps the logs generated by the specified pid to the tombstone, from both 589 * "system" and "main" log devices. Ideally we'd interleave the output. 590 */ 591 static void dump_logs(log_t* log, pid_t pid, bool tailOnly) 592 { 593 dump_log_file(log, pid, "/dev/log/system", tailOnly); 594 dump_log_file(log, pid, "/dev/log/main", tailOnly); 595 } 596 597 /* 598 * Dumps all information about the specified pid to the tombstone. 599 */ 600 static bool dump_crash(log_t* log, pid_t pid, pid_t tid, int signal, 601 bool dump_sibling_threads, int* total_sleep_time_usec) 602 { 603 /* don't copy log messages to tombstone unless this is a dev device */ 604 char value[PROPERTY_VALUE_MAX]; 605 property_get("ro.debuggable", value, "0"); 606 bool want_logs = (value[0] == '1'); 607 608 _LOG(log, false, 609 "*** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***\n"); 610 dump_build_info(log); 611 dump_revision_info(log); 612 dump_thread_info(log, pid, tid, true); 613 if(signal) { 614 dump_fault_addr(log, tid, signal); 615 } 616 617 ptrace_context_t* context = load_ptrace_context(tid); 618 dump_thread(context, log, tid, true, total_sleep_time_usec); 619 620 if (want_logs) { 621 dump_logs(log, pid, true); 622 } 623 624 bool detach_failed = false; 625 if (dump_sibling_threads) { 626 detach_failed = dump_sibling_thread_report(context, log, pid, tid, total_sleep_time_usec); 627 } 628 629 free_ptrace_context(context); 630 631 if (want_logs) { 632 dump_logs(log, pid, false); 633 } 634 return detach_failed; 635 } 636 637 /* 638 * find_and_open_tombstone - find an available tombstone slot, if any, of the 639 * form tombstone_XX where XX is 00 to MAX_TOMBSTONES-1, inclusive. If no 640 * file is available, we reuse the least-recently-modified file. 641 * 642 * Returns the path of the tombstone file, allocated using malloc(). Caller must free() it. 643 */ 644 static char* find_and_open_tombstone(int* fd) 645 { 646 unsigned long mtime = ULONG_MAX; 647 struct stat sb; 648 649 /* 650 * XXX: Our stat.st_mtime isn't time_t. If it changes, as it probably ought 651 * to, our logic breaks. This check will generate a warning if that happens. 652 */ 653 typecheck(mtime, sb.st_mtime); 654 655 /* 656 * In a single wolf-like pass, find an available slot and, in case none 657 * exist, find and record the least-recently-modified file. 658 */ 659 char path[128]; 660 int oldest = 0; 661 for (int i = 0; i < MAX_TOMBSTONES; i++) { 662 snprintf(path, sizeof(path), TOMBSTONE_DIR"/tombstone_%02d", i); 663 664 if (!stat(path, &sb)) { 665 if (sb.st_mtime < mtime) { 666 oldest = i; 667 mtime = sb.st_mtime; 668 } 669 continue; 670 } 671 if (errno != ENOENT) 672 continue; 673 674 *fd = open(path, O_CREAT | O_EXCL | O_WRONLY, 0600); 675 if (*fd < 0) 676 continue; /* raced ? */ 677 678 fchown(*fd, AID_SYSTEM, AID_SYSTEM); 679 return strdup(path); 680 } 681 682 /* we didn't find an available file, so we clobber the oldest one */ 683 snprintf(path, sizeof(path), TOMBSTONE_DIR"/tombstone_%02d", oldest); 684 *fd = open(path, O_CREAT | O_TRUNC | O_WRONLY, 0600); 685 if (*fd < 0) { 686 LOG("failed to open tombstone file '%s': %s\n", path, strerror(errno)); 687 return NULL; 688 } 689 fchown(*fd, AID_SYSTEM, AID_SYSTEM); 690 return strdup(path); 691 } 692 693 char* engrave_tombstone(pid_t pid, pid_t tid, int signal, 694 bool dump_sibling_threads, bool quiet, bool* detach_failed, 695 int* total_sleep_time_usec) { 696 mkdir(TOMBSTONE_DIR, 0755); 697 chown(TOMBSTONE_DIR, AID_SYSTEM, AID_SYSTEM); 698 699 #ifdef HAVE_SELINUX 700 if (selinux_android_restorecon(TOMBSTONE_DIR) == -1) { 701 *detach_failed = false; 702 return NULL; 703 } 704 #endif 705 706 int fd; 707 char* path = find_and_open_tombstone(&fd); 708 if (!path) { 709 *detach_failed = false; 710 return NULL; 711 } 712 713 log_t log; 714 log.tfd = fd; 715 log.quiet = quiet; 716 *detach_failed = dump_crash(&log, pid, tid, signal, dump_sibling_threads, 717 total_sleep_time_usec); 718 719 close(fd); 720 return path; 721 } 722