savecore.c revision 1.89
1/* $NetBSD: savecore.c,v 1.89 2019/11/06 07:29:08 mrg 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 40static char sccsid[] = "@(#)savecore.c 8.5 (Berkeley) 4/28/95"; 41#else 42__RCSID("$NetBSD: savecore.c,v 1.89 2019/11/06 07:29:08 mrg 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 74extern FILE *zopen(const char *fname, const char *mode); 75 76/* 77 * Note that KREAD_LOGWARN and KREAD_ERR take a variable name, not 78 * pointer to it, unlike KREAD() itself. 79 */ 80#define KREAD(kd, addr, p)\ 81 (kvm_read(kd, addr, (char *)(p), sizeof(*(p))) != sizeof(*(p))) 82#define KREAD_ERR(kd, addr, p, err) \ 83do { \ 84 if (KREAD(kd, addr, &(p)) != 0) { \ 85 err; \ 86 } \ 87} while (0) 88#define KREAD_LOGWARN(kd, addr, p, err) \ 89do { \ 90 if (KREAD(kd, addr, &(p)) != 0) { \ 91 syslog(LOG_WARNING, "%s:%d: kvm_read " #p ": %s", \ 92 __func__, __LINE__, kvm_geterr(kd)); \ 93 err; \ 94 } \ 95} while (0) 96 97static struct nlist current_nl[] = { /* Namelist for currently running system. */ 98#define X_DUMPDEV 0 99 { .n_name = "_dumpdev" }, 100#define X_DUMPLO 1 101 { .n_name = "_dumplo" }, 102#define X_TIME_SECOND 2 103 { .n_name = "_time_second" }, 104#define X_TIME 3 105 { .n_name = "_time" }, 106#define X_DUMPSIZE 4 107 { .n_name = "_dumpsize" }, 108#define X_VERSION 5 109 { .n_name = "_version" }, 110#define X_DUMPMAG 6 111 { .n_name = "_dumpmag" }, 112#define X_PANICSTR 7 113 { .n_name = "_panicstr" }, 114#define X_PANICSTART 8 115 { .n_name = "_panicstart" }, 116#define X_PANICEND 9 117 { .n_name = "_panicend" }, 118#define X_MSGBUF 10 119 { .n_name = "_msgbufp" }, 120#define X_DUMPCDEV 11 121 { .n_name = "_dumpcdev" }, 122#define X_SYMSZ 12 123 { .n_name = "_ksyms_symsz" }, 124#define X_STRSZ 13 125 { .n_name = "_ksyms_strsz" }, 126#define X_KHDR 14 127 { .n_name = "_ksyms_hdr" }, 128#define X_SYMTABS 15 129 { .n_name = "_ksyms_symtabs" }, 130 { .n_name = NULL }, 131}; 132static int cursyms[] = { X_DUMPDEV, X_DUMPLO, X_VERSION, X_DUMPMAG, X_DUMPCDEV, -1 }; 133static int dumpsyms[] = { X_TIME_SECOND, X_TIME, X_DUMPSIZE, X_VERSION, X_PANICSTR, 134 X_DUMPMAG, X_SYMSZ, X_STRSZ, X_KHDR, X_SYMTABS, -1 }; 135 136static struct nlist dump_nl[] = { /* Name list for dumped system. */ 137 { .n_name = "_dumpdev" }, /* Entries MUST be the same as */ 138 { .n_name = "_dumplo" }, /* those in current_nl[]. */ 139 { .n_name = "_time_second" }, 140 { .n_name = "_time" }, 141 { .n_name = "_dumpsize" }, 142 { .n_name = "_version" }, 143 { .n_name = "_dumpmag" }, 144 { .n_name = "_panicstr" }, 145 { .n_name = "_panicstart" }, 146 { .n_name = "_panicend" }, 147 { .n_name = "_msgbufp" }, 148 { .n_name = "_dumpcdev" }, 149 { .n_name = "_ksyms_symsz" }, 150 { .n_name = "_ksyms_strsz" }, 151 { .n_name = "_ksyms_hdr" }, 152 { .n_name = "_ksyms_symtabs" }, 153 { .n_name = NULL }, 154}; 155 156/* Types match kernel declarations. */ 157static off_t dumplo; /* where dump starts on dumpdev */ 158static u_int32_t dumpmag; /* magic number in dump */ 159static int dumpsize; /* amount of memory dumped */ 160static off_t dumpbytes; /* in bytes */ 161 162static const char *kernel; /* name of used kernel */ 163static const char *dirname; /* directory to save dumps in */ 164static char *ddname; /* name of dump device */ 165static dev_t dumpdev; /* dump device */ 166static dev_t dumpcdev = NODEV; /* dump device (char equivalent) */ 167static int dumpfd; /* read/write descriptor on dev */ 168static kvm_t *kd_dump; /* kvm descriptor on dev */ 169static time_t now; /* current date */ 170static char panic_mesg[1024]; 171static long panicstr; 172static char vers[1024]; 173static char gzmode[3]; 174 175static void check_kmem(void); 176static int check_space(void); 177static void clear_dump(void); 178static int Create(char *, int); 179static int dump_exists(int); 180static char *find_dev(dev_t, mode_t); 181static int get_crashtime(void); 182static void kmem_setup(int); 183static void Lseek(int, off_t, int); 184static int Open(const char *, int rw); 185static void save_core(int); 186__dead static void usage(const char *fmt, ...) __printflike(1, 2); 187 188int 189main(int argc, char *argv[]) 190{ 191 int ch, level, testonly, compress, force, clear, verbose; 192 char *ep; 193 194 kernel = NULL; 195 level = 1; /* default to fastest gzip compression */ 196 force = 0; 197 clear = 0; 198 testonly = 0; 199 verbose = 0; 200 compress = 0; 201 gzmode[0] = 'w'; 202 203 openlog("savecore", LOG_PERROR, LOG_DAEMON); 204 205 while ((ch = getopt(argc, argv, "cdfnN:vzZ:")) != -1) 206 switch(ch) { 207 case 'c': 208 clear = 1; 209 break; 210 case 'd': /* Not documented. */ 211 case 'v': 212 verbose = 1; 213 break; 214 case 'f': 215 force = 1; 216 break; 217 case 'n': 218 testonly = 1; 219 break; 220 case 'N': 221 kernel = optarg; 222 break; 223 case 'z': 224 compress = 1; 225 break; 226 case 'Z': 227 level = (int)strtol(optarg, &ep, 10); 228 if (level < 0 || level > 9) 229 usage("Invalid compression `%s'", optarg); 230 break; 231 case '?': 232 usage("Missing argument for flag `%c'", optopt); 233 default: 234 usage("Unknown flag `%c'", ch); 235 } 236 argc -= optind; 237 argv += optind; 238 239 if (argc != 0) 240 dirname = argv[0]; 241 else 242 dirname = "/var/crash"; 243 244 gzmode[1] = level + '0'; 245 246 (void)time(&now); 247 kmem_setup(verbose); 248 249 if (clear && !testonly) { 250 clear_dump(); 251 exit(0); 252 } 253 254 if (!dump_exists(verbose) && !force) 255 exit(1); 256 257 if (testonly) 258 /* If -n was passed and there was a dump, exit at level 0 */ 259 exit(0); 260 261 check_kmem(); 262 263 if (panicstr) 264 syslog(LOG_ALERT, "reboot after panic: %s", panic_mesg); 265 else 266 syslog(LOG_ALERT, "reboot"); 267 268 if ((!get_crashtime() || !check_space()) && !force) 269 exit(1); 270 271 save_core(compress); 272 273 clear_dump(); 274 exit(0); 275} 276 277static void 278kmem_setup(int verbose) 279{ 280 long l_dumplo; 281 kvm_t *kd_kern; 282 char errbuf[_POSIX2_LINE_MAX]; 283 int i, hdrsz; 284 285 /* 286 * Some names we need for the currently running system, others for 287 * the system that was running when the dump was made. The values 288 * obtained from the current system are used to look for things in 289 * /dev/kmem that cannot be found in the kernel namelist, but are 290 * presumed to be the same (since the disk partitions are probably 291 * the same!) 292 */ 293 kd_kern = kvm_openfiles(kernel, NULL, NULL, O_RDONLY, errbuf); 294 if (kd_kern == NULL) { 295 syslog(LOG_ERR, "%s: kvm_openfiles: %s", kernel, errbuf); 296 exit(1); 297 } 298 if (kvm_nlist(kd_kern, current_nl) == -1) 299 syslog(LOG_ERR, "%s: kvm_nlist: %s", kernel, 300 kvm_geterr(kd_kern)); 301 302 for (i = 0; cursyms[i] != -1; i++) { 303 if (current_nl[cursyms[i]].n_value != 0) 304 continue; 305 switch (cursyms[i]) { 306 case X_TIME_SECOND: 307 case X_TIME: 308 case X_DUMPCDEV: 309 break; 310 default: 311 syslog(LOG_ERR, "%s: %s not in namelist", 312 kernel, current_nl[cursyms[i]].n_name); 313 exit(1); 314 } 315 } 316 317 KREAD_LOGWARN(kd_kern, current_nl[X_DUMPDEV].n_value, dumpdev, exit(1)); 318 if (dumpdev == NODEV) { 319 syslog(LOG_WARNING, "no core dump (no dumpdev)"); 320 exit(1); 321 } 322 KREAD_LOGWARN(kd_kern, current_nl[X_DUMPLO].n_value, l_dumplo, exit(1)); 323 if (l_dumplo == -1) { 324 syslog(LOG_WARNING, "no core dump (invalid dumplo)"); 325 exit(1); 326 } 327 dumplo = DEV_BSIZE * (off_t) l_dumplo; 328 329 if (verbose) 330 (void)printf("dumplo = %lld (%ld * %ld)\n", 331 (long long)dumplo, (long)(dumplo / DEV_BSIZE), (long)DEV_BSIZE); 332 KREAD_LOGWARN(kd_kern, current_nl[X_DUMPMAG].n_value, dumpmag, exit(1)); 333 334 (void)kvm_read(kd_kern, current_nl[X_VERSION].n_value, vers, 335 sizeof(vers)); 336 vers[sizeof(vers) - 1] = '\0'; 337 338 if (current_nl[X_DUMPCDEV].n_value != 0) { 339 KREAD_LOGWARN(kd_kern, current_nl[X_DUMPCDEV].n_value, dumpcdev, 340 exit(1)); 341 ddname = find_dev(dumpcdev, S_IFCHR); 342 } else 343 ddname = find_dev(dumpdev, S_IFBLK); 344 if (strncmp(ddname, "/dev/cons", 8) == 0 || 345 strncmp(ddname, "/dev/tty", 7) == 0 || 346 strncmp(ddname, "/dev/pty", 7) == 0 || 347 strncmp(ddname, "/dev/pts", 7) == 0) { 348 syslog(LOG_ERR, "dumpdev %s is tty; override kernel", ddname); 349 exit(1); 350 } 351 dumpfd = Open(ddname, O_RDWR); 352 353 kd_dump = kvm_openfiles(kernel, ddname, NULL, O_RDWR, errbuf); 354 if (kd_dump == NULL) { 355 syslog(LOG_ERR, "%s: kvm_openfiles: %s", kernel, errbuf); 356 exit(1); 357 } 358 359 if (kvm_nlist(kd_dump, dump_nl) == -1) 360 syslog(LOG_ERR, "%s: kvm_nlist: %s", kernel, 361 kvm_geterr(kd_dump)); 362 363 for (i = 0; dumpsyms[i] != -1; i++) 364 if (dump_nl[dumpsyms[i]].n_value == 0 && 365 dumpsyms[i] != X_TIME_SECOND && 366 dumpsyms[i] != X_TIME) { 367 syslog(LOG_ERR, "%s: %s not in namelist", 368 kernel, dump_nl[dumpsyms[i]].n_name); 369 exit(1); 370 } 371 hdrsz = kvm_dump_mkheader(kd_dump, dumplo); 372 373 /* 374 * If 'hdrsz' == 0, kvm_dump_mkheader() failed on the magic-number 375 * checks, ergo no dump is present... 376 */ 377 if (hdrsz == 0) { 378 syslog(LOG_WARNING, "no core dump"); 379 exit(1); 380 } 381 if (hdrsz == -1) { 382 syslog(LOG_ERR, "%s: kvm_dump_mkheader: %s", kernel, 383 kvm_geterr(kd_dump)); 384 exit(1); 385 } 386 dumplo += hdrsz; 387 kvm_close(kd_kern); 388} 389 390static void 391check_kmem(void) 392{ 393 char *cp, *bufdata; 394 struct kern_msgbuf msgbuf, *bufp; 395 long panicloc, panicstart, panicend; 396 char core_vers[1024]; 397 398 (void)kvm_read(kd_dump, dump_nl[X_VERSION].n_value, core_vers, 399 sizeof(core_vers)); 400 core_vers[sizeof(core_vers) - 1] = '\0'; 401 402 if (strcmp(vers, core_vers) != 0) 403 syslog(LOG_WARNING, 404 "warning: %s version mismatch:\n\t%s\nand\t%s\n", 405 kvm_getkernelname(kd_dump), vers, core_vers); 406 407 panicstart = panicend = 0; 408 KREAD_LOGWARN(kd_dump, dump_nl[X_PANICSTART].n_value, panicstart, 409 goto nomsguf); 410 KREAD_LOGWARN(kd_dump, dump_nl[X_PANICEND].n_value, panicend, 411 goto nomsguf); 412 413 if (panicstart != 0 && panicend != 0) { 414 KREAD_LOGWARN(kd_dump, dump_nl[X_MSGBUF].n_value, bufp, 415 goto nomsguf); 416 /* Reads msg_bufs[1], but doesn't matter. */ 417 KREAD_LOGWARN(kd_dump, (long)bufp, msgbuf, 418 goto nomsguf); 419 if (msgbuf.msg_magic != MSG_MAGIC) { 420 syslog(LOG_WARNING, "msgbuf magic incorrect (%lx != %lx)", 421 msgbuf.msg_magic, (long)MSG_MAGIC); 422 goto nomsguf; 423 } 424 bufdata = malloc(msgbuf.msg_bufs); 425 if (bufdata == NULL) { 426 syslog(LOG_WARNING, "couldn't allocate space for msgbuf data"); 427 goto nomsguf; 428 } 429 if (kvm_read(kd_dump, (long)&bufp->msg_bufc, bufdata, 430 msgbuf.msg_bufs) != msgbuf.msg_bufs) { 431 syslog(LOG_WARNING, "kvm_read dmesg buffer: %s", 432 kvm_geterr(kd_dump)); 433 free(bufdata); 434 goto nomsguf; 435 } 436 cp = panic_mesg; 437 while (panicstart != panicend && cp < &panic_mesg[sizeof(panic_mesg)-1]) { 438 *cp++ = bufdata[panicstart]; 439 panicstart++; 440 if (panicstart >= msgbuf.msg_bufs) 441 panicstart = 0; 442 } 443 /* Don't end in a new-line */ 444 cp = &panic_mesg[strlen(panic_mesg)] - 1; 445 if (*cp == '\n') 446 *cp = '\0'; 447 panic_mesg[sizeof(panic_mesg) - 1] = '\0'; 448 free(bufdata); 449 450 panicstr = 1; /* anything not zero */ 451 return; 452 } 453nomsguf: 454 KREAD_LOGWARN(kd_dump, dump_nl[X_PANICSTR].n_value, panicstr, 455 return); 456 if (panicstr) { 457 cp = panic_mesg; 458 panicloc = panicstr; 459 do { 460 if (KREAD(kd_dump, panicloc, cp) != 0) { 461 syslog(LOG_WARNING, "kvm_read msgbuf: %s", 462 kvm_geterr(kd_dump)); 463 break; 464 } 465 panicloc++; 466 } while (*cp++ && cp < &panic_mesg[sizeof(panic_mesg)-1]); 467 panic_mesg[sizeof(panic_mesg) - 1] = '\0'; 468 } 469} 470 471static int 472dump_exists(int verbose) 473{ 474 u_int32_t newdumpmag; 475 476 /* Read the dump magic and size. */ 477 KREAD_ERR(kd_dump, dump_nl[X_DUMPMAG].n_value, newdumpmag, return 0); 478 KREAD_ERR(kd_dump, dump_nl[X_DUMPSIZE].n_value, dumpsize, return 0); 479 480 dumpbytes = (off_t)dumpsize * getpagesize(); 481 482 /* 483 * Return zero if core dump doesn't seem to be there, and note 484 * it for syslog. This check and return happens after the dump size 485 * is read, so dumpsize is whether or not the core is valid (for -f). 486 */ 487 if (newdumpmag != dumpmag) { 488 if (verbose) 489 syslog(LOG_WARNING, "magic number mismatch " 490 "(%#x != %#x)", newdumpmag, dumpmag); 491 syslog(LOG_WARNING, "no core dump"); 492 return (0); 493 } 494 return (1); 495} 496 497static void 498clear_dump(void) 499{ 500 if (kvm_dump_inval(kd_dump) == -1) 501 syslog(LOG_ERR, "%s: kvm_dump_inval: %s", ddname, 502 kvm_geterr(kd_dump)); 503 504} 505 506static char buf[1024 * 1024]; 507 508static void 509save_kernel(FILE *fp, char *path) 510{ 511 int nw, nr, ifd; 512 513 ifd = Open(kernel, O_RDONLY); 514 while ((nr = read(ifd, buf, sizeof(buf))) > 0) { 515 nw = fwrite(buf, 1, nr, fp); 516 if (nw != nr) { 517 syslog(LOG_ERR, "%s: %s", 518 path, strerror(nw == 0 ? EIO : errno)); 519 syslog(LOG_WARNING, 520 "WARNING: kernel may be incomplete"); 521 exit(1); 522 } 523 } 524 if (nr < 0) { 525 syslog(LOG_ERR, "%s: %m", kernel); 526 syslog(LOG_WARNING, "WARNING: kernel may be incomplete"); 527 exit(1); 528 } 529} 530 531static int 532ksymsget(u_long addr, void *ptr, size_t size) 533{ 534 535 if ((size_t)kvm_read(kd_dump, addr, ptr, size) != size) { 536 syslog(LOG_WARNING, "kvm_read ksyms: %s", kvm_geterr(kd_dump)); 537 return 1; 538 } 539 return 0; 540} 541 542static int 543save_ksyms(FILE *fp, char *path) 544{ 545 struct ksyms_hdr khdr; 546 int nw, symsz, strsz; 547 TAILQ_HEAD(, ksyms_symtab) symtabs; 548 struct ksyms_symtab st, *stptr; 549 void *p; 550 551 /* Get basic info and ELF headers, check if ksyms was on. */ 552 if (ksymsget(dump_nl[X_KHDR].n_value, &khdr, sizeof(khdr))) 553 return 1; 554 if (ksymsget(dump_nl[X_SYMSZ].n_value, &symsz, sizeof(symsz))) 555 return 1; 556 if (ksymsget(dump_nl[X_STRSZ].n_value, &strsz, sizeof(strsz))) 557 return 1; 558 if (symsz == 0 || strsz == 0) 559 return 1; 560 561 /* Update the ELF section headers for symbols/strings. */ 562 khdr.kh_shdr[SYMTAB].sh_size = symsz; 563 khdr.kh_shdr[SYMTAB].sh_info = symsz / sizeof(Elf_Sym); 564 khdr.kh_shdr[STRTAB].sh_offset = symsz + 565 khdr.kh_shdr[SYMTAB].sh_offset; 566 khdr.kh_shdr[STRTAB].sh_size = strsz; 567 568 /* Write out the ELF headers. */ 569 nw = fwrite(&khdr, 1, sizeof(khdr), fp); 570 if (nw != sizeof(khdr)) { 571 syslog(LOG_ERR, "%s: %s", 572 path, strerror(nw == 0 ? EIO : errno)); 573 syslog(LOG_WARNING, 574 "WARNING: kernel may be incomplete"); 575 exit(1); 576 } 577 578 /* Dump symbol table. */ 579 if (ksymsget(dump_nl[X_SYMTABS].n_value, &symtabs, sizeof(symtabs))) 580 return 1; 581 stptr = TAILQ_FIRST(&symtabs); 582 while (stptr != NULL) { 583 if (ksymsget((u_long)stptr, &st, sizeof(st))) 584 return 1; 585 stptr = TAILQ_NEXT(&st, sd_queue); 586 if ((p = malloc(st.sd_symsize)) == NULL) 587 return 1; 588 if (ksymsget((u_long)st.sd_symstart, p, st.sd_symsize)) { 589 free(p); 590 return 1; 591 } 592 nw = fwrite(p, 1, st.sd_symsize, fp); 593 free(p); 594 if (nw != st.sd_symsize) { 595 syslog(LOG_ERR, "%s: %s", 596 path, strerror(nw == 0 ? EIO : errno)); 597 syslog(LOG_WARNING, 598 "WARNING: kernel may be incomplete"); 599 exit(1); 600 } 601 } 602 603 /* Dump string table. */ 604 if (ksymsget(dump_nl[X_SYMTABS].n_value, &symtabs, sizeof(symtabs))) 605 return 1; 606 stptr = TAILQ_FIRST(&symtabs); 607 while (stptr != NULL) { 608 if (ksymsget((u_long)stptr, &st, sizeof(st))) 609 return 1; 610 stptr = TAILQ_NEXT(&st, sd_queue); 611 if ((p = malloc(st.sd_symsize)) == NULL) 612 return 1; 613 if (ksymsget((u_long)st.sd_strstart, p, st.sd_strsize)) { 614 free(p); 615 return 1; 616 } 617 nw = fwrite(p, 1, st.sd_strsize, fp); 618 free(p); 619 if (nw != st.sd_strsize) { 620 syslog(LOG_ERR, "%s: %s", 621 path, strerror(nw == 0 ? EIO : errno)); 622 syslog(LOG_WARNING, 623 "WARNING: kernel may be incomplete"); 624 exit(1); 625 } 626 } 627 628 return 0; 629} 630 631static void 632save_core(int compress) 633{ 634 FILE *fp; 635 int bounds, ifd, nr, nw, ofd, tryksyms; 636 char path[MAXPATHLEN], rbuf[MAXPATHLEN]; 637 const char *rawp; 638 639 ofd = -1; 640 /* 641 * Get the current number and update the bounds file. Do the update 642 * now, because may fail later and don't want to overwrite anything. 643 */ 644 umask(066); 645 (void)snprintf(path, sizeof(path), "%s/bounds", dirname); 646 if ((fp = fopen(path, "r")) == NULL) 647 goto err1; 648 if (fgets(buf, sizeof(buf), fp) == NULL) { 649 if (ferror(fp)) 650err1: syslog(LOG_WARNING, "%s: %m", path); 651 bounds = 0; 652 } else 653 bounds = atoi(buf); 654 if (fp != NULL) 655 (void)fclose(fp); 656 if ((fp = fopen(path, "w")) == NULL) 657 syslog(LOG_ERR, "%s: %m", path); 658 else { 659 (void)fprintf(fp, "%d\n", bounds + 1); 660 (void)fclose(fp); 661 } 662 663 /* Create the core file. */ 664 (void)snprintf(path, sizeof(path), "%s/netbsd.%d.core%s", 665 dirname, bounds, compress ? ".gz" : ""); 666 if (compress) { 667 if ((fp = zopen(path, gzmode)) == NULL) { 668 syslog(LOG_ERR, "%s: %m", path); 669 exit(1); 670 } 671 } else { 672 ofd = Create(path, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH); 673 fp = fdopen(ofd, "w"); 674 if (fp == NULL) { 675 syslog(LOG_ERR, "%s: fdopen: %m", path); 676 exit(1); 677 } 678 } 679 680 if (dumpcdev == NODEV) { 681 /* Open the raw device. */ 682 rawp = getdiskrawname(rbuf, sizeof(rbuf), ddname); 683 if (rawp == NULL) { 684 syslog(LOG_WARNING, "%s: %m; can't convert to raw", 685 ddname); 686 rawp = ddname; 687 } 688 if ((ifd = open(rawp, O_RDONLY)) == -1) { 689 syslog(LOG_WARNING, "%s: %m; using block device", 690 rawp); 691 ifd = dumpfd; 692 } 693 } else { 694 rawp = ddname; 695 ifd = dumpfd; 696 } 697 698 /* Seek to the start of the core. */ 699 Lseek(ifd, dumplo, SEEK_SET); 700 701 if (kvm_dump_wrtheader(kd_dump, fp, (int32_t)dumpbytes) == -1) { 702 syslog(LOG_ERR, "kvm_dump_wrtheader: %s : %s", path, 703 kvm_geterr(kd_dump)); 704 exit(1); 705 } 706 707 /* Copy the core file. */ 708 syslog(LOG_NOTICE, "writing %score to %s", 709 compress ? "compressed " : "", path); 710 for (; dumpbytes > (off_t)0; dumpbytes -= (off_t)nr) { 711 char nbuf[7]; 712 humanize_number(nbuf, 7, dumpbytes, "", HN_AUTOSCALE, 0); 713 (void)printf("%7s\r", nbuf); 714 (void)fflush(stdout); 715 nr = read(ifd, buf, MIN(dumpbytes, (off_t)sizeof(buf))); 716 if (nr <= 0) { 717 if (nr == 0) 718 syslog(LOG_WARNING, 719 "WARNING: EOF on dump device"); 720 else 721 syslog(LOG_ERR, "%s: %m", rawp); 722 goto err2; 723 } 724 nw = fwrite(buf, 1, nr, fp); 725 if (nw != nr) { 726 syslog(LOG_ERR, "%s: %s", 727 path, strerror(nw == 0 ? EIO : errno)); 728err2: syslog(LOG_WARNING, 729 "WARNING: core may be incomplete"); 730 (void)printf("\n"); 731 exit(1); 732 } 733 } 734 if (dumpcdev == NODEV) 735 (void)close(ifd); 736 (void)fclose(fp); 737 738 /* Create a kernel. */ 739 (void)snprintf(path, sizeof(path), "%s/netbsd.%d%s", 740 dirname, bounds, compress ? ".gz" : ""); 741 syslog(LOG_NOTICE, "writing %skernel to %s", 742 compress ? "compressed " : "", path); 743 for (tryksyms = 1;; tryksyms = 0) { 744 if (compress) { 745 if ((fp = zopen(path, gzmode)) == NULL) { 746 syslog(LOG_ERR, "%s: %m", path); 747 exit(1); 748 } 749 } else { 750 ofd = Create(path, S_IRUSR | S_IWUSR); 751 fp = fdopen(ofd, "w"); 752 if (fp == NULL) { 753 syslog(LOG_ERR, "fdopen: %m"); 754 exit(1); 755 } 756 } 757 if (tryksyms) { 758 if (!save_ksyms(fp, path)) 759 break; 760 (void)fclose(fp); 761 unlink(path); 762 } else { 763 save_kernel(fp, path); 764 break; 765 } 766 } 767 (void)fclose(fp); 768 769 /* 770 * For development systems where the crash occurs during boot 771 * to multiuser. 772 */ 773 sync(); 774 sleep(1); 775 sync(); 776 sleep(1); 777} 778 779static char * 780find_dev(dev_t dev, mode_t type) 781{ 782 DIR *dfd; 783 struct dirent *dir; 784 struct stat sb; 785 char *dp, device[MAXPATHLEN + 1], *p; 786 size_t l; 787 788 if ((dfd = opendir(_PATH_DEV)) == NULL) { 789 syslog(LOG_ERR, "%s: %m", _PATH_DEV); 790 exit(1); 791 } 792 strlcpy(device, _PATH_DEV, sizeof(device)); 793 p = &device[strlen(device)]; 794 l = sizeof(device) - strlen(device); 795 while ((dir = readdir(dfd))) { 796 strlcpy(p, dir->d_name, l); 797 if (lstat(device, &sb)) { 798 syslog(LOG_ERR, "%s: %m", device); 799 continue; 800 } 801 if ((sb.st_mode & S_IFMT) != type) 802 continue; 803 if (dev == sb.st_rdev) { 804 closedir(dfd); 805 if ((dp = strdup(device)) == NULL) { 806 syslog(LOG_ERR, "%m"); 807 exit(1); 808 } 809 return (dp); 810 } 811 } 812 closedir(dfd); 813 syslog(LOG_ERR, "can't find device %lld/%lld", 814 (long long)major(dev), (long long)minor(dev)); 815 exit(1); 816} 817 818static int 819get_crashtime(void) 820{ 821 time_t dumptime; /* Time the dump was taken. */ 822 struct timeval dtime; 823 824 if (KREAD(kd_dump, dump_nl[X_TIME_SECOND].n_value, &dumptime) != 0) { 825 if (KREAD(kd_dump, dump_nl[X_TIME].n_value, &dtime) != 0) { 826 syslog(LOG_WARNING, "kvm_read dumptime: %s (and _time_second " 827 "is not defined also)", kvm_geterr(kd_dump)); 828 return (0); 829 } 830 dumptime = dtime.tv_sec; 831 } 832 if (dumptime == 0) { 833 syslog(LOG_WARNING, "dump time is zero"); 834 return (0); 835 } 836 syslog(LOG_INFO, "system went down at %s", ctime(&dumptime)); 837#define LEEWAY (60 * SECSPERDAY) 838 if (dumptime < now - LEEWAY || dumptime > now + LEEWAY) { 839 syslog(LOG_WARNING, "dump time is unreasonable"); 840 return (0); 841 } 842 return (1); 843} 844 845static int 846check_space(void) 847{ 848 FILE *fp; 849 off_t minfree, spacefree, kernelsize, needed; 850 struct stat st; 851 struct statvfs fsbuf; 852 char mbuf[100], path[MAXPATHLEN]; 853 854 /* XXX assume a reasonable default, unless we find a kernel. */ 855 kernelsize = 20 * 1024 * 1024; 856 if (!stat(kernel, &st)) kernelsize = st.st_blocks * S_BLKSIZE; 857 if (statvfs(dirname, &fsbuf) < 0) { 858 syslog(LOG_ERR, "%s: %m", dirname); 859 exit(1); 860 } 861 spacefree = fsbuf.f_bavail; 862 spacefree *= fsbuf.f_frsize; 863 spacefree /= 1024; 864 865 (void)snprintf(path, sizeof(path), "%s/minfree", dirname); 866 if ((fp = fopen(path, "r")) == NULL) 867 minfree = 0; 868 else { 869 if (fgets(mbuf, sizeof(mbuf), fp) == NULL) 870 minfree = 0; 871 else 872 minfree = atoi(mbuf); 873 (void)fclose(fp); 874 } 875 876 needed = (dumpbytes + kernelsize) / 1024; 877 if (minfree > 0 && spacefree - needed < minfree) { 878 syslog(LOG_WARNING, 879 "no dump, not enough free space in %s", dirname); 880 return (0); 881 } 882 if (spacefree - needed < minfree) 883 syslog(LOG_WARNING, 884 "dump performed, but free space threshold crossed"); 885 return (1); 886} 887 888static int 889Open(const char *name, int rw) 890{ 891 int fd; 892 893 if ((fd = open(name, rw, 0)) < 0) { 894 syslog(LOG_ERR, "%s: %m", name); 895 exit(1); 896 } 897 return (fd); 898} 899 900static void 901Lseek(int fd, off_t off, int flag) 902{ 903 off_t ret; 904 905 ret = lseek(fd, off, flag); 906 if (ret == -1) { 907 syslog(LOG_ERR, "lseek: %m"); 908 exit(1); 909 } 910} 911 912static int 913Create(char *file, int mode) 914{ 915 int fd; 916 917 fd = open(file, O_WRONLY | O_CREAT | O_TRUNC, mode); 918 if (fd < 0) { 919 syslog(LOG_ERR, "%s: %m", file); 920 exit(1); 921 } 922 return (fd); 923} 924 925static void 926usage(const char *fmt, ...) 927{ 928 va_list ap; 929 va_start(ap, fmt); 930 (void)vsyslog(LOG_ERR, fmt, ap); 931 va_end(ap); 932 (void)syslog(LOG_ERR, 933 "Usage: %s [-cfnvz] [-N system] [-Z level] [directory]", 934 getprogname()); 935 exit(1); 936} 937