savecore.c revision 1.83
1 /* $NetBSD: savecore.c,v 1.83 2011/09/12 21:22:07 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 1986, 1992, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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 #ifndef lint 34 __COPYRIGHT("@(#) Copyright (c) 1986, 1992, 1993\ 35 The Regents of the University of California. All rights reserved."); 36 #endif /* not lint */ 37 38 #ifndef lint 39 #if 0 40 static char sccsid[] = "@(#)savecore.c 8.5 (Berkeley) 4/28/95"; 41 #else 42 __RCSID("$NetBSD: savecore.c,v 1.83 2011/09/12 21:22:07 christos Exp $"); 43 #endif 44 #endif /* not lint */ 45 46 #define _KSYMS_PRIVATE 47 48 #include <stdbool.h> 49 50 #include <sys/param.h> 51 #include <sys/mount.h> 52 #include <sys/msgbuf.h> 53 #include <sys/syslog.h> 54 #include <sys/time.h> 55 #include <sys/ksyms.h> 56 57 #include <dirent.h> 58 #include <errno.h> 59 #include <fcntl.h> 60 #include <nlist.h> 61 #include <paths.h> 62 #include <stddef.h> 63 #include <stdio.h> 64 #include <stdlib.h> 65 #include <string.h> 66 #include <time.h> 67 #include <tzfile.h> 68 #include <unistd.h> 69 #include <util.h> 70 #include <limits.h> 71 #include <stdarg.h> 72 #include <kvm.h> 73 74 extern FILE *zopen(const char *fname, const char *mode); 75 76 #define KREAD(kd, addr, p)\ 77 (kvm_read(kd, addr, (char *)(p), sizeof(*(p))) != sizeof(*(p))) 78 79 static struct nlist current_nl[] = { /* Namelist for currently running system. */ 80 #define X_DUMPDEV 0 81 { .n_name = "_dumpdev" }, 82 #define X_DUMPLO 1 83 { .n_name = "_dumplo" }, 84 #define X_TIME_SECOND 2 85 { .n_name = "_time_second" }, 86 #define X_TIME 3 87 { .n_name = "_time" }, 88 #define X_DUMPSIZE 4 89 { .n_name = "_dumpsize" }, 90 #define X_VERSION 5 91 { .n_name = "_version" }, 92 #define X_DUMPMAG 6 93 { .n_name = "_dumpmag" }, 94 #define X_PANICSTR 7 95 { .n_name = "_panicstr" }, 96 #define X_PANICSTART 8 97 { .n_name = "_panicstart" }, 98 #define X_PANICEND 9 99 { .n_name = "_panicend" }, 100 #define X_MSGBUF 10 101 { .n_name = "_msgbufp" }, 102 #define X_DUMPCDEV 11 103 { .n_name = "_dumpcdev" }, 104 #define X_SYMSZ 12 105 { .n_name = "_ksyms_symsz" }, 106 #define X_STRSZ 13 107 { .n_name = "_ksyms_strsz" }, 108 #define X_KHDR 14 109 { .n_name = "_ksyms_hdr" }, 110 #define X_SYMTABS 15 111 { .n_name = "_ksyms_symtabs" }, 112 { .n_name = NULL }, 113 }; 114 static int cursyms[] = { X_DUMPDEV, X_DUMPLO, X_VERSION, X_DUMPMAG, X_DUMPCDEV, -1 }; 115 static int dumpsyms[] = { X_TIME_SECOND, X_TIME, X_DUMPSIZE, X_VERSION, X_PANICSTR, 116 X_DUMPMAG, X_SYMSZ, X_STRSZ, X_KHDR, X_SYMTABS, -1 }; 117 118 static struct nlist dump_nl[] = { /* Name list for dumped system. */ 119 { .n_name = "_dumpdev" }, /* Entries MUST be the same as */ 120 { .n_name = "_dumplo" }, /* those in current_nl[]. */ 121 { .n_name = "_time_second" }, 122 { .n_name = "_time" }, 123 { .n_name = "_dumpsize" }, 124 { .n_name = "_version" }, 125 { .n_name = "_dumpmag" }, 126 { .n_name = "_panicstr" }, 127 { .n_name = "_panicstart" }, 128 { .n_name = "_panicend" }, 129 { .n_name = "_msgbufp" }, 130 { .n_name = "_dumpcdev" }, 131 { .n_name = "_ksyms_symsz" }, 132 { .n_name = "_ksyms_strsz" }, 133 { .n_name = "_ksyms_hdr" }, 134 { .n_name = "_ksyms_symtabs" }, 135 { .n_name = NULL }, 136 }; 137 138 /* Types match kernel declarations. */ 139 static off_t dumplo; /* where dump starts on dumpdev */ 140 static u_int32_t dumpmag; /* magic number in dump */ 141 static int dumpsize; /* amount of memory dumped */ 142 static off_t dumpbytes; /* in bytes */ 143 144 static const char *kernel; /* name of used kernel */ 145 static const char *dirname; /* directory to save dumps in */ 146 static char *ddname; /* name of dump device */ 147 static dev_t dumpdev; /* dump device */ 148 static dev_t dumpcdev = NODEV; /* dump device (char equivalent) */ 149 static int dumpfd; /* read/write descriptor on dev */ 150 static kvm_t *kd_dump; /* kvm descriptor on dev */ 151 static time_t now; /* current date */ 152 static char panic_mesg[1024]; 153 static long panicstr; 154 static char vers[1024]; 155 static char gzmode[3]; 156 157 static int clear, compress, force, verbose; /* flags */ 158 159 static void check_kmem(void); 160 static int check_space(void); 161 static void clear_dump(void); 162 static int Create(char *, int); 163 static int dump_exists(void); 164 static char *find_dev(dev_t, mode_t); 165 static int get_crashtime(void); 166 static void kmem_setup(void); 167 static void Lseek(int, off_t, int); 168 static int Open(const char *, int rw); 169 static char *rawname(char *s); 170 static void save_core(void); 171 __dead static void usage(const char *fmt, ...) __printflike(1, 2); 172 173 int 174 main(int argc, char *argv[]) 175 { 176 int ch, level, testonly; 177 char *ep; 178 179 kernel = NULL; 180 level = 1; /* default to fastest gzip compression */ 181 testonly = 0; 182 gzmode[0] = 'w'; 183 184 openlog("savecore", LOG_PERROR, LOG_DAEMON); 185 186 while ((ch = getopt(argc, argv, "cdfnN:vzZ:")) != -1) 187 switch(ch) { 188 case 'c': 189 clear = 1; 190 break; 191 case 'd': /* Not documented. */ 192 case 'v': 193 verbose = 1; 194 break; 195 case 'f': 196 force = 1; 197 break; 198 case 'n': 199 testonly = 1; 200 break; 201 case 'N': 202 kernel = optarg; 203 break; 204 case 'z': 205 compress = 1; 206 break; 207 case 'Z': 208 level = (int)strtol(optarg, &ep, 10); 209 if (level < 0 || level > 9) 210 usage("Invalid compression `%s'", optarg); 211 break; 212 case '?': 213 default: 214 usage("Unknown flag `%c'", ch); 215 } 216 argc -= optind; 217 argv += optind; 218 219 if (argc != 0) 220 dirname = argv[0]; 221 else 222 dirname = "/var/crash"; 223 224 gzmode[1] = level + '0'; 225 226 (void)time(&now); 227 kmem_setup(); 228 229 if (clear && !testonly) { 230 clear_dump(); 231 exit(0); 232 } 233 234 if (!dump_exists() && !force) 235 exit(1); 236 237 if (testonly) 238 /* If -n was passed and there was a dump, exit at level 0 */ 239 exit(0); 240 241 check_kmem(); 242 243 if (panicstr) 244 syslog(LOG_ALERT, "reboot after panic: %s", panic_mesg); 245 else 246 syslog(LOG_ALERT, "reboot"); 247 248 if ((!get_crashtime() || !check_space()) && !force) 249 exit(1); 250 251 save_core(); 252 253 clear_dump(); 254 exit(0); 255 } 256 257 static void 258 kmem_setup(void) 259 { 260 kvm_t *kd_kern; 261 char errbuf[_POSIX2_LINE_MAX]; 262 int i, hdrsz; 263 264 /* 265 * Some names we need for the currently running system, others for 266 * the system that was running when the dump was made. The values 267 * obtained from the current system are used to look for things in 268 * /dev/kmem that cannot be found in the kernel namelist, but are 269 * presumed to be the same (since the disk partitions are probably 270 * the same!) 271 */ 272 kd_kern = kvm_openfiles(kernel, NULL, NULL, O_RDONLY, errbuf); 273 if (kd_kern == NULL) { 274 syslog(LOG_ERR, "%s: kvm_openfiles: %s", kernel, errbuf); 275 exit(1); 276 } 277 if (kvm_nlist(kd_kern, current_nl) == -1) 278 syslog(LOG_ERR, "%s: kvm_nlist: %s", kernel, 279 kvm_geterr(kd_kern)); 280 281 for (i = 0; cursyms[i] != -1; i++) { 282 if (current_nl[cursyms[i]].n_value != 0) 283 continue; 284 switch (cursyms[i]) { 285 case X_TIME_SECOND: 286 case X_TIME: 287 case X_DUMPCDEV: 288 break; 289 default: 290 syslog(LOG_ERR, "%s: %s not in namelist", 291 kernel, current_nl[cursyms[i]].n_name); 292 exit(1); 293 } 294 } 295 296 if (KREAD(kd_kern, current_nl[X_DUMPDEV].n_value, &dumpdev) != 0) { 297 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_kern)); 298 exit(1); 299 } 300 if (dumpdev == NODEV) { 301 syslog(LOG_WARNING, "no core dump (no dumpdev)"); 302 exit(1); 303 } 304 { 305 long l_dumplo; 306 307 if (KREAD(kd_kern, current_nl[X_DUMPLO].n_value, &l_dumplo) != 0) { 308 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_kern)); 309 exit(1); 310 } 311 if (l_dumplo == -1) { 312 syslog(LOG_WARNING, "no core dump (invalid dumplo)"); 313 exit(1); 314 } 315 dumplo = DEV_BSIZE * (off_t) l_dumplo; 316 } 317 318 if (verbose) 319 (void)printf("dumplo = %lld (%ld * %ld)\n", 320 (long long)dumplo, (long)(dumplo / DEV_BSIZE), (long)DEV_BSIZE); 321 if (KREAD(kd_kern, current_nl[X_DUMPMAG].n_value, &dumpmag) != 0) { 322 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_kern)); 323 exit(1); 324 } 325 326 (void)kvm_read(kd_kern, current_nl[X_VERSION].n_value, vers, 327 sizeof(vers)); 328 vers[sizeof(vers) - 1] = '\0'; 329 330 if (current_nl[X_DUMPCDEV].n_value != 0) { 331 if (KREAD(kd_kern, current_nl[X_DUMPCDEV].n_value, 332 &dumpcdev) != 0) { 333 syslog(LOG_WARNING, "kvm_read: %s", 334 kvm_geterr(kd_kern)); 335 exit(1); 336 } 337 ddname = find_dev(dumpcdev, S_IFCHR); 338 } else 339 ddname = find_dev(dumpdev, S_IFBLK); 340 if (strncmp(ddname, "/dev/cons", 8) == 0 || 341 strncmp(ddname, "/dev/tty", 7) == 0 || 342 strncmp(ddname, "/dev/pty", 7) == 0 || 343 strncmp(ddname, "/dev/pts", 7) == 0) { 344 syslog(LOG_ERR, "dumpdev %s is tty; override kernel", ddname); 345 exit(1); 346 } 347 dumpfd = Open(ddname, O_RDWR); 348 349 kd_dump = kvm_openfiles(kernel, ddname, NULL, O_RDWR, errbuf); 350 if (kd_dump == NULL) { 351 syslog(LOG_ERR, "%s: kvm_openfiles: %s", kernel, errbuf); 352 exit(1); 353 } 354 355 if (kvm_nlist(kd_dump, dump_nl) == -1) 356 syslog(LOG_ERR, "%s: kvm_nlist: %s", kernel, 357 kvm_geterr(kd_dump)); 358 359 for (i = 0; dumpsyms[i] != -1; i++) 360 if (dump_nl[dumpsyms[i]].n_value == 0 && 361 dumpsyms[i] != X_TIME_SECOND && 362 dumpsyms[i] != X_TIME) { 363 syslog(LOG_ERR, "%s: %s not in namelist", 364 kernel, dump_nl[dumpsyms[i]].n_name); 365 exit(1); 366 } 367 hdrsz = kvm_dump_mkheader(kd_dump, dumplo); 368 369 /* 370 * If 'hdrsz' == 0, kvm_dump_mkheader() failed on the magic-number 371 * checks, ergo no dump is present... 372 */ 373 if (hdrsz == 0) { 374 syslog(LOG_WARNING, "no core dump"); 375 exit(1); 376 } 377 if (hdrsz == -1) { 378 syslog(LOG_ERR, "%s: kvm_dump_mkheader: %s", kernel, 379 kvm_geterr(kd_dump)); 380 exit(1); 381 } 382 dumplo += hdrsz; 383 kvm_close(kd_kern); 384 } 385 386 static void 387 check_kmem(void) 388 { 389 char *cp, *bufdata; 390 struct kern_msgbuf msgbuf, *bufp; 391 long panicloc, panicstart, panicend; 392 char core_vers[1024]; 393 394 (void)kvm_read(kd_dump, dump_nl[X_VERSION].n_value, core_vers, 395 sizeof(core_vers)); 396 core_vers[sizeof(core_vers) - 1] = '\0'; 397 398 if (strcmp(vers, core_vers) != 0) 399 syslog(LOG_WARNING, 400 "warning: %s version mismatch:\n\t%s\nand\t%s\n", 401 kvm_getkernelname(kd_dump), vers, core_vers); 402 403 panicstart = panicend = 0; 404 if (KREAD(kd_dump, dump_nl[X_PANICSTART].n_value, &panicstart) != 0) { 405 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump)); 406 goto nomsguf; 407 } 408 if (KREAD(kd_dump, dump_nl[X_PANICEND].n_value, &panicend) != 0) { 409 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump)); 410 goto nomsguf; 411 } 412 if (panicstart != 0 && panicend != 0) { 413 if (KREAD(kd_dump, dump_nl[X_MSGBUF].n_value, &bufp)) { 414 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump)); 415 goto nomsguf; 416 } 417 if (kvm_read(kd_dump, (long)bufp, &msgbuf, 418 offsetof(struct kern_msgbuf, msg_bufc)) != 419 offsetof(struct kern_msgbuf, msg_bufc)) { 420 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump)); 421 goto nomsguf; 422 } 423 if (msgbuf.msg_magic != MSG_MAGIC) { 424 syslog(LOG_WARNING, "msgbuf magic incorrect"); 425 goto nomsguf; 426 } 427 bufdata = malloc(msgbuf.msg_bufs); 428 if (bufdata == NULL) { 429 syslog(LOG_WARNING, "couldn't allocate space for msgbuf data"); 430 goto nomsguf; 431 } 432 if (kvm_read(kd_dump, (long)&bufp->msg_bufc, bufdata, 433 msgbuf.msg_bufs) != msgbuf.msg_bufs) { 434 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump)); 435 free(bufdata); 436 goto nomsguf; 437 } 438 cp = panic_mesg; 439 while (panicstart != panicend && cp < &panic_mesg[sizeof(panic_mesg)-1]) { 440 *cp++ = bufdata[panicstart]; 441 panicstart++; 442 if (panicstart >= msgbuf.msg_bufs) 443 panicstart = 0; 444 } 445 /* Don't end in a new-line */ 446 cp = &panic_mesg[strlen(panic_mesg)] - 1; 447 if (*cp == '\n') 448 *cp = '\0'; 449 panic_mesg[sizeof(panic_mesg) - 1] = '\0'; 450 free(bufdata); 451 452 panicstr = 1; /* anything not zero */ 453 return; 454 } 455 nomsguf: 456 if (KREAD(kd_dump, dump_nl[X_PANICSTR].n_value, &panicstr) != 0) { 457 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump)); 458 return; 459 } 460 if (panicstr) { 461 cp = panic_mesg; 462 panicloc = panicstr; 463 do { 464 if (KREAD(kd_dump, panicloc, cp) != 0) { 465 syslog(LOG_WARNING, "kvm_read: %s", 466 kvm_geterr(kd_dump)); 467 break; 468 } 469 panicloc++; 470 } while (*cp++ && cp < &panic_mesg[sizeof(panic_mesg)-1]); 471 panic_mesg[sizeof(panic_mesg) - 1] = '\0'; 472 } 473 } 474 475 static int 476 dump_exists(void) 477 { 478 u_int32_t newdumpmag; 479 480 if (KREAD(kd_dump, dump_nl[X_DUMPMAG].n_value, &newdumpmag) != 0) { 481 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump)); 482 return (0); 483 } 484 485 /* Read the dump size. */ 486 if (KREAD(kd_dump, dump_nl[X_DUMPSIZE].n_value, &dumpsize) != 0) { 487 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump)); 488 return (0); 489 } 490 dumpbytes = (off_t)dumpsize * getpagesize(); 491 492 /* 493 * Return zero if core dump doesn't seem to be there, and note 494 * it for syslog. This check and return happens after the dump size 495 * is read, so dumpsize is whether or not the core is valid (for -f). 496 */ 497 if (newdumpmag != dumpmag) { 498 if (verbose) 499 syslog(LOG_WARNING, "magic number mismatch " 500 "(0x%x != 0x%x)", newdumpmag, dumpmag); 501 syslog(LOG_WARNING, "no core dump"); 502 return (0); 503 } 504 return (1); 505 } 506 507 static void 508 clear_dump(void) 509 { 510 if (kvm_dump_inval(kd_dump) == -1) 511 syslog(LOG_ERR, "%s: kvm_dump_inval: %s", ddname, 512 kvm_geterr(kd_dump)); 513 514 } 515 516 static char buf[1024 * 1024]; 517 518 static void 519 save_kernel(int ofd, FILE *fp, char *path) 520 { 521 int nw, nr, ifd; 522 523 ifd = Open(kernel, O_RDONLY); 524 while ((nr = read(ifd, buf, sizeof(buf))) > 0) { 525 if (compress) 526 nw = fwrite(buf, 1, nr, fp); 527 else 528 nw = write(ofd, buf, nr); 529 if (nw != nr) { 530 syslog(LOG_ERR, "%s: %s", 531 path, strerror(nw == 0 ? EIO : errno)); 532 syslog(LOG_WARNING, 533 "WARNING: kernel may be incomplete"); 534 exit(1); 535 } 536 } 537 if (nr < 0) { 538 syslog(LOG_ERR, "%s: %m", kernel); 539 syslog(LOG_WARNING, "WARNING: kernel may be incomplete"); 540 exit(1); 541 } 542 } 543 544 static int 545 ksymsget(u_long addr, void *ptr, size_t size) 546 { 547 548 if ((size_t)kvm_read(kd_dump, addr, ptr, size) != size) { 549 syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump)); 550 return 1; 551 } 552 return 0; 553 } 554 555 static int 556 save_ksyms(int ofd, FILE *fp, char *path) 557 { 558 struct ksyms_hdr khdr; 559 int nw, symsz, strsz; 560 TAILQ_HEAD(, ksyms_symtab) symtabs; 561 struct ksyms_symtab st, *stptr; 562 void *p; 563 564 /* Get basic info and ELF headers, check if ksyms was on. */ 565 if (ksymsget(dump_nl[X_KHDR].n_value, &khdr, sizeof(khdr))) 566 return 1; 567 if (ksymsget(dump_nl[X_SYMSZ].n_value, &symsz, sizeof(symsz))) 568 return 1; 569 if (ksymsget(dump_nl[X_STRSZ].n_value, &strsz, sizeof(strsz))) 570 return 1; 571 if (symsz == 0 || strsz == 0) 572 return 1; 573 574 /* Update the ELF section headers for symbols/strings. */ 575 khdr.kh_shdr[SYMTAB].sh_size = symsz; 576 khdr.kh_shdr[SYMTAB].sh_info = symsz / sizeof(Elf_Sym); 577 khdr.kh_shdr[STRTAB].sh_offset = symsz + 578 khdr.kh_shdr[SYMTAB].sh_offset; 579 khdr.kh_shdr[STRTAB].sh_size = strsz; 580 581 /* Write out the ELF headers. */ 582 if (compress) 583 nw = fwrite(&khdr, 1, sizeof(khdr), fp); 584 else 585 nw = write(ofd, &khdr, sizeof(khdr)); 586 if (nw != sizeof(khdr)) { 587 syslog(LOG_ERR, "%s: %s", 588 path, strerror(nw == 0 ? EIO : errno)); 589 syslog(LOG_WARNING, 590 "WARNING: kernel may be incomplete"); 591 exit(1); 592 } 593 594 /* Dump symbol table. */ 595 if (ksymsget(dump_nl[X_SYMTABS].n_value, &symtabs, sizeof(symtabs))) 596 return 1; 597 stptr = TAILQ_FIRST(&symtabs); 598 while (stptr != NULL) { 599 if (ksymsget((u_long)stptr, &st, sizeof(st))) 600 return 1; 601 stptr = TAILQ_NEXT(&st, sd_queue); 602 if ((p = malloc(st.sd_symsize)) == NULL) 603 return 1; 604 if (ksymsget((u_long)st.sd_symstart, p, st.sd_symsize)) { 605 free(p); 606 return 1; 607 } 608 if (compress) 609 nw = fwrite(p, 1, st.sd_symsize, fp); 610 else 611 nw = write(ofd, p, st.sd_symsize); 612 free(p); 613 if (nw != st.sd_symsize) { 614 syslog(LOG_ERR, "%s: %s", 615 path, strerror(nw == 0 ? EIO : errno)); 616 syslog(LOG_WARNING, 617 "WARNING: kernel may be incomplete"); 618 exit(1); 619 } 620 } 621 622 /* Dump string table. */ 623 if (ksymsget(dump_nl[X_SYMTABS].n_value, &symtabs, sizeof(symtabs))) 624 return 1; 625 stptr = TAILQ_FIRST(&symtabs); 626 while (stptr != NULL) { 627 if (ksymsget((u_long)stptr, &st, sizeof(st))) 628 return 1; 629 stptr = TAILQ_NEXT(&st, sd_queue); 630 if ((p = malloc(st.sd_symsize)) == NULL) 631 return 1; 632 if (ksymsget((u_long)st.sd_strstart, p, st.sd_strsize)) { 633 free(p); 634 return 1; 635 } 636 if (compress) 637 nw = fwrite(p, 1, st.sd_strsize, fp); 638 else 639 nw = write(ofd, p, st.sd_strsize); 640 free(p); 641 if (nw != st.sd_strsize) { 642 syslog(LOG_ERR, "%s: %s", 643 path, strerror(nw == 0 ? EIO : errno)); 644 syslog(LOG_WARNING, 645 "WARNING: kernel may be incomplete"); 646 exit(1); 647 } 648 } 649 650 return 0; 651 } 652 653 static void 654 save_core(void) 655 { 656 FILE *fp; 657 int bounds, ifd, nr, nw, ofd, tryksyms; 658 char *rawp, path[MAXPATHLEN]; 659 660 ofd = -1; 661 /* 662 * Get the current number and update the bounds file. Do the update 663 * now, because may fail later and don't want to overwrite anything. 664 */ 665 umask(066); 666 (void)snprintf(path, sizeof(path), "%s/bounds", dirname); 667 if ((fp = fopen(path, "r")) == NULL) 668 goto err1; 669 if (fgets(buf, sizeof(buf), fp) == NULL) { 670 if (ferror(fp)) 671 err1: syslog(LOG_WARNING, "%s: %m", path); 672 bounds = 0; 673 } else 674 bounds = atoi(buf); 675 if (fp != NULL) 676 (void)fclose(fp); 677 if ((fp = fopen(path, "w")) == NULL) 678 syslog(LOG_ERR, "%s: %m", path); 679 else { 680 (void)fprintf(fp, "%d\n", bounds + 1); 681 (void)fclose(fp); 682 } 683 684 /* Create the core file. */ 685 (void)snprintf(path, sizeof(path), "%s/netbsd.%d.core%s", 686 dirname, bounds, compress ? ".gz" : ""); 687 if (compress) { 688 if ((fp = zopen(path, gzmode)) == NULL) { 689 syslog(LOG_ERR, "%s: %m", path); 690 exit(1); 691 } 692 } else { 693 ofd = Create(path, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH); 694 fp = fdopen(ofd, "w"); 695 if (fp == NULL) { 696 syslog(LOG_ERR, "%s: fdopen: %m", path); 697 exit(1); 698 } 699 } 700 701 if (dumpcdev == NODEV) { 702 /* Open the raw device. */ 703 rawp = rawname(ddname); 704 if ((ifd = open(rawp, O_RDONLY)) == -1) { 705 syslog(LOG_WARNING, "%s: %m; using block device", 706 rawp); 707 ifd = dumpfd; 708 } 709 } else { 710 rawp = ddname; 711 ifd = dumpfd; 712 } 713 714 /* Seek to the start of the core. */ 715 Lseek(ifd, dumplo, SEEK_SET); 716 717 if (kvm_dump_wrtheader(kd_dump, fp, (int32_t)dumpbytes) == -1) { 718 syslog(LOG_ERR, "kvm_dump_wrtheader: %s : %s", path, 719 kvm_geterr(kd_dump)); 720 exit(1); 721 } 722 723 /* Copy the core file. */ 724 syslog(LOG_NOTICE, "writing %score to %s", 725 compress ? "compressed " : "", path); 726 for (; dumpbytes > (off_t)0; dumpbytes -= (off_t)nr) { 727 char nbuf[7]; 728 humanize_number(nbuf, 7, dumpbytes, "", HN_AUTOSCALE, 0); 729 (void)printf("%7s\r", nbuf); 730 (void)fflush(stdout); 731 nr = read(ifd, buf, MIN(dumpbytes, (off_t)sizeof(buf))); 732 if (nr <= 0) { 733 if (nr == 0) 734 syslog(LOG_WARNING, 735 "WARNING: EOF on dump device"); 736 else 737 syslog(LOG_ERR, "%s: %m", rawp); 738 goto err2; 739 } 740 nw = fwrite(buf, 1, nr, fp); 741 if (nw != nr) { 742 syslog(LOG_ERR, "%s: %s", 743 path, strerror(nw == 0 ? EIO : errno)); 744 err2: syslog(LOG_WARNING, 745 "WARNING: core may be incomplete"); 746 (void)printf("\n"); 747 exit(1); 748 } 749 } 750 if (dumpcdev == NODEV) 751 (void)close(ifd); 752 (void)fclose(fp); 753 754 /* Create a kernel. */ 755 (void)snprintf(path, sizeof(path), "%s/netbsd.%d%s", 756 dirname, bounds, compress ? ".gz" : ""); 757 syslog(LOG_NOTICE, "writing %skernel to %s", 758 compress ? "compressed " : "", path); 759 for (tryksyms = 1;; tryksyms = 0) { 760 if (compress) { 761 if ((fp = zopen(path, gzmode)) == NULL) { 762 syslog(LOG_ERR, "%s: %m", path); 763 exit(1); 764 } 765 } else 766 ofd = Create(path, S_IRUSR | S_IWUSR); 767 if (tryksyms) { 768 if (!save_ksyms(ofd, fp, path)) 769 break; 770 if (compress) 771 (void)fclose(fp); 772 else 773 (void)close(ofd); 774 unlink(path); 775 } else { 776 save_kernel(ofd, fp, path); 777 break; 778 } 779 } 780 if (compress) 781 (void)fclose(fp); 782 else 783 (void)close(ofd); 784 785 /* 786 * For development systems where the crash occurs during boot 787 * to multiuser. 788 */ 789 sync(); 790 sleep(1); 791 sync(); 792 sleep(1); 793 } 794 795 static char * 796 find_dev(dev_t dev, mode_t type) 797 { 798 DIR *dfd; 799 struct dirent *dir; 800 struct stat sb; 801 char *dp, device[MAXPATHLEN + 1], *p; 802 size_t l; 803 804 if ((dfd = opendir(_PATH_DEV)) == NULL) { 805 syslog(LOG_ERR, "%s: %m", _PATH_DEV); 806 exit(1); 807 } 808 strlcpy(device, _PATH_DEV, sizeof(device)); 809 p = &device[strlen(device)]; 810 l = sizeof(device) - strlen(device); 811 while ((dir = readdir(dfd))) { 812 strlcpy(p, dir->d_name, l); 813 if (lstat(device, &sb)) { 814 syslog(LOG_ERR, "%s: %m", device); 815 continue; 816 } 817 if ((sb.st_mode & S_IFMT) != type) 818 continue; 819 if (dev == sb.st_rdev) { 820 closedir(dfd); 821 if ((dp = strdup(device)) == NULL) { 822 syslog(LOG_ERR, "%m"); 823 exit(1); 824 } 825 return (dp); 826 } 827 } 828 closedir(dfd); 829 syslog(LOG_ERR, "can't find device %lld/%lld", 830 (long long)major(dev), (long long)minor(dev)); 831 exit(1); 832 } 833 834 static char * 835 rawname(char *s) 836 { 837 char *sl; 838 char name[MAXPATHLEN]; 839 840 if ((sl = strrchr(s, '/')) == NULL || sl[1] == '0') { 841 syslog(LOG_ERR, 842 "can't make raw dump device name from %s", s); 843 return (s); 844 } 845 (void)snprintf(name, sizeof(name), "%.*s/r%s", (int)(sl - s), s, 846 sl + 1); 847 if ((sl = strdup(name)) == NULL) { 848 syslog(LOG_ERR, "%m"); 849 exit(1); 850 } 851 return (sl); 852 } 853 854 static int 855 get_crashtime(void) 856 { 857 time_t dumptime; /* Time the dump was taken. */ 858 struct timeval dtime; 859 860 if (KREAD(kd_dump, dump_nl[X_TIME_SECOND].n_value, &dumptime) != 0) { 861 if (KREAD(kd_dump, dump_nl[X_TIME].n_value, &dtime) != 0) { 862 syslog(LOG_WARNING, "kvm_read: %s (and _time_second " 863 "is not defined also)", kvm_geterr(kd_dump)); 864 return (0); 865 } 866 dumptime = dtime.tv_sec; 867 } 868 if (dumptime == 0) { 869 syslog(LOG_WARNING, "dump time is zero"); 870 return (0); 871 } 872 syslog(LOG_INFO, "system went down at %s", ctime(&dumptime)); 873 #define LEEWAY (60 * SECSPERDAY) 874 if (dumptime < now - LEEWAY || dumptime > now + LEEWAY) { 875 syslog(LOG_WARNING, "dump time is unreasonable"); 876 return (0); 877 } 878 return (1); 879 } 880 881 static int 882 check_space(void) 883 { 884 FILE *fp; 885 off_t minfree, spacefree, kernelsize, needed; 886 struct stat st; 887 struct statvfs fsbuf; 888 char mbuf[100], path[MAXPATHLEN]; 889 890 /* XXX assume a reasonable default, unless we find a kernel. */ 891 kernelsize = 20 * 1024 * 1024; 892 if (!stat(kernel, &st)) kernelsize = st.st_blocks * S_BLKSIZE; 893 if (statvfs(dirname, &fsbuf) < 0) { 894 syslog(LOG_ERR, "%s: %m", dirname); 895 exit(1); 896 } 897 spacefree = fsbuf.f_bavail; 898 spacefree *= fsbuf.f_frsize; 899 spacefree /= 1024; 900 901 (void)snprintf(path, sizeof(path), "%s/minfree", dirname); 902 if ((fp = fopen(path, "r")) == NULL) 903 minfree = 0; 904 else { 905 if (fgets(mbuf, sizeof(mbuf), fp) == NULL) 906 minfree = 0; 907 else 908 minfree = atoi(mbuf); 909 (void)fclose(fp); 910 } 911 912 needed = (dumpbytes + kernelsize) / 1024; 913 if (minfree > 0 && spacefree - needed < minfree) { 914 syslog(LOG_WARNING, 915 "no dump, not enough free space in %s", dirname); 916 return (0); 917 } 918 if (spacefree - needed < minfree) 919 syslog(LOG_WARNING, 920 "dump performed, but free space threshold crossed"); 921 return (1); 922 } 923 924 static int 925 Open(const char *name, int rw) 926 { 927 int fd; 928 929 if ((fd = open(name, rw, 0)) < 0) { 930 syslog(LOG_ERR, "%s: %m", name); 931 exit(1); 932 } 933 return (fd); 934 } 935 936 static void 937 Lseek(int fd, off_t off, int flag) 938 { 939 off_t ret; 940 941 ret = lseek(fd, off, flag); 942 if (ret == -1) { 943 syslog(LOG_ERR, "lseek: %m"); 944 exit(1); 945 } 946 } 947 948 static int 949 Create(char *file, int mode) 950 { 951 int fd; 952 953 fd = open(file, O_WRONLY | O_CREAT | O_TRUNC, mode); 954 if (fd < 0) { 955 syslog(LOG_ERR, "%s: %m", file); 956 exit(1); 957 } 958 return (fd); 959 } 960 961 static void 962 usage(const char *fmt, ...) 963 { 964 va_list ap; 965 va_start(ap, fmt); 966 (void)vsyslog(LOG_ERR, fmt, ap); 967 va_end(ap); 968 (void)syslog(LOG_ERR, 969 "Usage: %s [-cfnvz] [-N system] [-Z level] [directory]", 970 getprogname()); 971 exit(1); 972 } 973
Indexes created Fri Sep 26 20:09:58 GMT 2025