1 /* $NetBSD: kvm.c,v 1.100 2012/08/26 23:09:42 martin Exp $ */ 2 3 /*- 4 * Copyright (c) 1989, 1992, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software developed by the Computer Systems 8 * Engineering group at Lawrence Berkeley Laboratory under DARPA contract 9 * BG 91-66 and contributed to Berkeley. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #include <sys/cdefs.h> 37 #if defined(LIBC_SCCS) && !defined(lint) 38 #if 0 39 static char sccsid[] = "@(#)kvm.c 8.2 (Berkeley) 2/13/94"; 40 #else 41 __RCSID("$NetBSD: kvm.c,v 1.100 2012/08/26 23:09:42 martin Exp $"); 42 #endif 43 #endif /* LIBC_SCCS and not lint */ 44 45 #include <sys/param.h> 46 #include <sys/user.h> 47 #include <sys/lwp.h> 48 #include <sys/proc.h> 49 #include <sys/ioctl.h> 50 #include <sys/stat.h> 51 #include <sys/sysctl.h> 52 53 #include <sys/core.h> 54 #include <sys/exec.h> 55 #include <sys/kcore.h> 56 #include <sys/ksyms.h> 57 #include <sys/types.h> 58 59 #include <uvm/uvm_extern.h> 60 61 #include <machine/cpu.h> 62 63 #include <ctype.h> 64 #include <errno.h> 65 #include <fcntl.h> 66 #include <limits.h> 67 #include <nlist.h> 68 #include <paths.h> 69 #include <stdarg.h> 70 #include <stdio.h> 71 #include <stdlib.h> 72 #include <string.h> 73 #include <unistd.h> 74 #include <kvm.h> 75 76 #include "kvm_private.h" 77 78 static int _kvm_get_header(kvm_t *); 79 static kvm_t *_kvm_open(kvm_t *, const char *, const char *, 80 const char *, int, char *); 81 static int clear_gap(kvm_t *, bool (*)(void *, const void *, size_t), 82 void *, size_t); 83 static off_t Lseek(kvm_t *, int, off_t, int); 84 static ssize_t Pread(kvm_t *, int, void *, size_t, off_t); 85 86 char * 87 kvm_geterr(kvm_t *kd) 88 { 89 return (kd->errbuf); 90 } 91 92 const char * 93 kvm_getkernelname(kvm_t *kd) 94 { 95 return kd->kernelname; 96 } 97 98 /* 99 * Report an error using printf style arguments. "program" is kd->program 100 * on hard errors, and 0 on soft errors, so that under sun error emulation, 101 * only hard errors are printed out (otherwise, programs like gdb will 102 * generate tons of error messages when trying to access bogus pointers). 103 */ 104 void 105 _kvm_err(kvm_t *kd, const char *program, const char *fmt, ...) 106 { 107 va_list ap; 108 109 va_start(ap, fmt); 110 if (program != NULL) { 111 (void)fprintf(stderr, "%s: ", program); 112 (void)vfprintf(stderr, fmt, ap); 113 (void)fputc('\n', stderr); 114 } else 115 (void)vsnprintf(kd->errbuf, 116 sizeof(kd->errbuf), fmt, ap); 117 118 va_end(ap); 119 } 120 121 void 122 _kvm_syserr(kvm_t *kd, const char *program, const char *fmt, ...) 123 { 124 va_list ap; 125 size_t n; 126 127 va_start(ap, fmt); 128 if (program != NULL) { 129 (void)fprintf(stderr, "%s: ", program); 130 (void)vfprintf(stderr, fmt, ap); 131 (void)fprintf(stderr, ": %s\n", strerror(errno)); 132 } else { 133 char *cp = kd->errbuf; 134 135 (void)vsnprintf(cp, sizeof(kd->errbuf), fmt, ap); 136 n = strlen(cp); 137 (void)snprintf(&cp[n], sizeof(kd->errbuf) - n, ": %s", 138 strerror(errno)); 139 } 140 va_end(ap); 141 } 142 143 void * 144 _kvm_malloc(kvm_t *kd, size_t n) 145 { 146 void *p; 147 148 if ((p = malloc(n)) == NULL) 149 _kvm_err(kd, kd->program, "%s", strerror(errno)); 150 return (p); 151 } 152 153 /* 154 * Wrapper around the lseek(2) system call; calls _kvm_syserr() for us 155 * in the event of emergency. 156 */ 157 static off_t 158 Lseek(kvm_t *kd, int fd, off_t offset, int whence) 159 { 160 off_t off; 161 162 errno = 0; 163 164 if ((off = lseek(fd, offset, whence)) == -1 && errno != 0) { 165 _kvm_syserr(kd, kd->program, "Lseek"); 166 return ((off_t)-1); 167 } 168 return (off); 169 } 170 171 ssize_t 172 _kvm_pread(kvm_t *kd, int fd, void *buf, size_t size, off_t off) 173 { 174 ptrdiff_t moff; 175 void *newbuf; 176 size_t dsize; 177 ssize_t rv; 178 off_t doff; 179 180 /* If aligned nothing to do. */ 181 if (((off % kd->fdalign) | (size % kd->fdalign)) == 0) { 182 return pread(fd, buf, size, off); 183 } 184 185 /* 186 * Otherwise must buffer. We can't tolerate short reads in this 187 * case (lazy bum). 188 */ 189 moff = (ptrdiff_t)off % kd->fdalign; 190 doff = off - moff; 191 dsize = moff + size + kd->fdalign - 1; 192 dsize -= dsize % kd->fdalign; 193 if (kd->iobufsz < dsize) { 194 newbuf = realloc(kd->iobuf, dsize); 195 if (newbuf == NULL) { 196 _kvm_syserr(kd, 0, "cannot allocate I/O buffer"); 197 return (-1); 198 } 199 kd->iobuf = newbuf; 200 kd->iobufsz = dsize; 201 } 202 rv = pread(fd, kd->iobuf, dsize, doff); 203 if (rv < size + moff) 204 return -1; 205 memcpy(buf, kd->iobuf + moff, size); 206 return size; 207 } 208 209 /* 210 * Wrapper around the pread(2) system call; calls _kvm_syserr() for us 211 * in the event of emergency. 212 */ 213 static ssize_t 214 Pread(kvm_t *kd, int fd, void *buf, size_t nbytes, off_t offset) 215 { 216 ssize_t rv; 217 218 errno = 0; 219 220 if ((rv = _kvm_pread(kd, fd, buf, nbytes, offset)) != nbytes && 221 errno != 0) 222 _kvm_syserr(kd, kd->program, "Pread"); 223 return (rv); 224 } 225 226 static kvm_t * 227 _kvm_open(kvm_t *kd, const char *uf, const char *mf, const char *sf, int flag, 228 char *errout) 229 { 230 struct stat st; 231 int ufgiven; 232 233 kd->pmfd = -1; 234 kd->vmfd = -1; 235 kd->swfd = -1; 236 kd->nlfd = -1; 237 kd->alive = KVM_ALIVE_DEAD; 238 kd->procbase = NULL; 239 kd->procbase_len = 0; 240 kd->procbase2 = NULL; 241 kd->procbase2_len = 0; 242 kd->lwpbase = NULL; 243 kd->lwpbase_len = 0; 244 kd->nbpg = getpagesize(); 245 kd->swapspc = NULL; 246 kd->argspc = NULL; 247 kd->argspc_len = 0; 248 kd->argbuf = NULL; 249 kd->argv = NULL; 250 kd->vmst = NULL; 251 kd->vm_page_buckets = NULL; 252 kd->kcore_hdr = NULL; 253 kd->cpu_dsize = 0; 254 kd->cpu_data = NULL; 255 kd->dump_off = 0; 256 kd->fdalign = 1; 257 kd->iobuf = NULL; 258 kd->iobufsz = 0; 259 260 if (flag & KVM_NO_FILES) { 261 kd->alive = KVM_ALIVE_SYSCTL; 262 return(kd); 263 } 264 265 /* 266 * Call the MD open hook. This sets: 267 * usrstack, min_uva, max_uva 268 */ 269 if (_kvm_mdopen(kd)) { 270 _kvm_err(kd, kd->program, "md init failed"); 271 goto failed; 272 } 273 274 ufgiven = (uf != NULL); 275 if (!ufgiven) { 276 #ifdef CPU_BOOTED_KERNEL 277 /* 130 is 128 + '/' + '\0' */ 278 static char booted_kernel[130]; 279 int mib[2], rc; 280 size_t len; 281 282 mib[0] = CTL_MACHDEP; 283 mib[1] = CPU_BOOTED_KERNEL; 284 booted_kernel[0] = '/'; 285 booted_kernel[1] = '\0'; 286 len = sizeof(booted_kernel) - 2; 287 rc = sysctl(&mib[0], 2, &booted_kernel[1], &len, NULL, 0); 288 booted_kernel[sizeof(booted_kernel) - 1] = '\0'; 289 uf = (booted_kernel[1] == '/') ? 290 &booted_kernel[1] : &booted_kernel[0]; 291 if (rc != -1) 292 rc = stat(uf, &st); 293 if (rc != -1 && !S_ISREG(st.st_mode)) 294 rc = -1; 295 if (rc == -1) 296 #endif /* CPU_BOOTED_KERNEL */ 297 uf = _PATH_UNIX; 298 } 299 else if (strlen(uf) >= MAXPATHLEN) { 300 _kvm_err(kd, kd->program, "exec file name too long"); 301 goto failed; 302 } 303 if (flag & ~O_RDWR) { 304 _kvm_err(kd, kd->program, "bad flags arg"); 305 goto failed; 306 } 307 if (mf == 0) 308 mf = _PATH_MEM; 309 if (sf == 0) 310 sf = _PATH_DRUM; 311 312 /* 313 * Open the kernel namelist. If /dev/ksyms doesn't 314 * exist, open the current kernel. 315 */ 316 if (ufgiven == 0) 317 kd->nlfd = open(_PATH_KSYMS, O_RDONLY | O_CLOEXEC, 0); 318 if (kd->nlfd < 0) { 319 if ((kd->nlfd = open(uf, O_RDONLY | O_CLOEXEC, 0)) < 0) { 320 _kvm_syserr(kd, kd->program, "%s", uf); 321 goto failed; 322 } 323 strlcpy(kd->kernelname, uf, sizeof(kd->kernelname)); 324 } else { 325 strlcpy(kd->kernelname, _PATH_KSYMS, sizeof(kd->kernelname)); 326 /* 327 * We're here because /dev/ksyms was opened 328 * successfully. However, we don't want to keep it 329 * open, so we close it now. Later, we will open 330 * it again, since it will be the only case where 331 * kd->nlfd is negative. 332 */ 333 close(kd->nlfd); 334 kd->nlfd = -1; 335 } 336 337 if ((kd->pmfd = open(mf, flag | O_CLOEXEC, 0)) < 0) { 338 _kvm_syserr(kd, kd->program, "%s", mf); 339 goto failed; 340 } 341 if (fstat(kd->pmfd, &st) < 0) { 342 _kvm_syserr(kd, kd->program, "%s", mf); 343 goto failed; 344 } 345 if (S_ISCHR(st.st_mode) && strcmp(mf, _PATH_MEM) == 0) { 346 /* 347 * If this is /dev/mem, open kmem too. (Maybe we should 348 * make it work for either /dev/mem or /dev/kmem -- in either 349 * case you're working with a live kernel.) 350 */ 351 if ((kd->vmfd = open(_PATH_KMEM, flag | O_CLOEXEC, 0)) < 0) { 352 _kvm_syserr(kd, kd->program, "%s", _PATH_KMEM); 353 goto failed; 354 } 355 kd->alive = KVM_ALIVE_FILES; 356 if ((kd->swfd = open(sf, flag | O_CLOEXEC, 0)) < 0) { 357 if (errno != ENXIO) { 358 _kvm_syserr(kd, kd->program, "%s", sf); 359 goto failed; 360 } 361 /* swap is not configured? not fatal */ 362 } 363 } else { 364 kd->fdalign = DEV_BSIZE; /* XXX */ 365 /* 366 * This is a crash dump. 367 * Initialize the virtual address translation machinery. 368 * 369 * If there is no valid core header, fail silently here. 370 * The address translations however will fail without 371 * header. Things can be made to run by calling 372 * kvm_dump_mkheader() before doing any translation. 373 */ 374 if (_kvm_get_header(kd) == 0) { 375 if (_kvm_initvtop(kd) < 0) 376 goto failed; 377 } 378 } 379 return (kd); 380 failed: 381 /* 382 * Copy out the error if doing sane error semantics. 383 */ 384 if (errout != 0) 385 (void)strlcpy(errout, kd->errbuf, _POSIX2_LINE_MAX); 386 (void)kvm_close(kd); 387 return (0); 388 } 389 390 /* 391 * The kernel dump file (from savecore) contains: 392 * kcore_hdr_t kcore_hdr; 393 * kcore_seg_t cpu_hdr; 394 * (opaque) cpu_data; (size is cpu_hdr.c_size) 395 * kcore_seg_t mem_hdr; 396 * (memory) mem_data; (size is mem_hdr.c_size) 397 * 398 * Note: khdr is padded to khdr.c_hdrsize; 399 * cpu_hdr and mem_hdr are padded to khdr.c_seghdrsize 400 */ 401 static int 402 _kvm_get_header(kvm_t *kd) 403 { 404 kcore_hdr_t kcore_hdr; 405 kcore_seg_t cpu_hdr; 406 kcore_seg_t mem_hdr; 407 size_t offset; 408 ssize_t sz; 409 410 /* 411 * Read the kcore_hdr_t 412 */ 413 sz = Pread(kd, kd->pmfd, &kcore_hdr, sizeof(kcore_hdr), (off_t)0); 414 if (sz != sizeof(kcore_hdr)) 415 return (-1); 416 417 /* 418 * Currently, we only support dump-files made by the current 419 * architecture... 420 */ 421 if ((CORE_GETMAGIC(kcore_hdr) != KCORE_MAGIC) || 422 (CORE_GETMID(kcore_hdr) != MID_MACHINE)) 423 return (-1); 424 425 /* 426 * Currently, we only support exactly 2 segments: cpu-segment 427 * and data-segment in exactly that order. 428 */ 429 if (kcore_hdr.c_nseg != 2) 430 return (-1); 431 432 /* 433 * Save away the kcore_hdr. All errors after this 434 * should do a to "goto fail" to deallocate things. 435 */ 436 kd->kcore_hdr = _kvm_malloc(kd, sizeof(kcore_hdr)); 437 memcpy(kd->kcore_hdr, &kcore_hdr, sizeof(kcore_hdr)); 438 offset = kcore_hdr.c_hdrsize; 439 440 /* 441 * Read the CPU segment header 442 */ 443 sz = Pread(kd, kd->pmfd, &cpu_hdr, sizeof(cpu_hdr), (off_t)offset); 444 if (sz != sizeof(cpu_hdr)) 445 goto fail; 446 if ((CORE_GETMAGIC(cpu_hdr) != KCORESEG_MAGIC) || 447 (CORE_GETFLAG(cpu_hdr) != CORE_CPU)) 448 goto fail; 449 offset += kcore_hdr.c_seghdrsize; 450 451 /* 452 * Read the CPU segment DATA. 453 */ 454 kd->cpu_dsize = cpu_hdr.c_size; 455 kd->cpu_data = _kvm_malloc(kd, cpu_hdr.c_size); 456 if (kd->cpu_data == NULL) 457 goto fail; 458 sz = Pread(kd, kd->pmfd, kd->cpu_data, cpu_hdr.c_size, (off_t)offset); 459 if (sz != cpu_hdr.c_size) 460 goto fail; 461 offset += cpu_hdr.c_size; 462 463 /* 464 * Read the next segment header: data segment 465 */ 466 sz = Pread(kd, kd->pmfd, &mem_hdr, sizeof(mem_hdr), (off_t)offset); 467 if (sz != sizeof(mem_hdr)) 468 goto fail; 469 offset += kcore_hdr.c_seghdrsize; 470 471 if ((CORE_GETMAGIC(mem_hdr) != KCORESEG_MAGIC) || 472 (CORE_GETFLAG(mem_hdr) != CORE_DATA)) 473 goto fail; 474 475 kd->dump_off = offset; 476 return (0); 477 478 fail: 479 if (kd->kcore_hdr != NULL) { 480 free(kd->kcore_hdr); 481 kd->kcore_hdr = NULL; 482 } 483 if (kd->cpu_data != NULL) { 484 free(kd->cpu_data); 485 kd->cpu_data = NULL; 486 kd->cpu_dsize = 0; 487 } 488 return (-1); 489 } 490 491 /* 492 * The format while on the dump device is: (new format) 493 * kcore_seg_t cpu_hdr; 494 * (opaque) cpu_data; (size is cpu_hdr.c_size) 495 * kcore_seg_t mem_hdr; 496 * (memory) mem_data; (size is mem_hdr.c_size) 497 */ 498 int 499 kvm_dump_mkheader(kvm_t *kd, off_t dump_off) 500 { 501 kcore_seg_t cpu_hdr; 502 size_t hdr_size; 503 ssize_t sz; 504 505 if (kd->kcore_hdr != NULL) { 506 _kvm_err(kd, kd->program, "already has a dump header"); 507 return (-1); 508 } 509 if (ISALIVE(kd)) { 510 _kvm_err(kd, kd->program, "don't use on live kernel"); 511 return (-1); 512 } 513 514 /* 515 * Validate new format crash dump 516 */ 517 sz = Pread(kd, kd->pmfd, &cpu_hdr, sizeof(cpu_hdr), dump_off); 518 if (sz != sizeof(cpu_hdr)) { 519 _kvm_err(kd, 0, "read %zx bytes at offset %"PRIx64 520 " for cpu_hdr instead of requested %zu", 521 sz, dump_off, sizeof(cpu_hdr)); 522 return (-1); 523 } 524 if ((CORE_GETMAGIC(cpu_hdr) != KCORE_MAGIC) 525 || (CORE_GETMID(cpu_hdr) != MID_MACHINE)) { 526 _kvm_err(kd, 0, "invalid magic in cpu_hdr"); 527 return (0); 528 } 529 hdr_size = ALIGN(sizeof(cpu_hdr)); 530 531 /* 532 * Read the CPU segment. 533 */ 534 kd->cpu_dsize = cpu_hdr.c_size; 535 kd->cpu_data = _kvm_malloc(kd, kd->cpu_dsize); 536 if (kd->cpu_data == NULL) { 537 _kvm_err(kd, kd->program, "no cpu_data"); 538 goto fail; 539 } 540 sz = Pread(kd, kd->pmfd, kd->cpu_data, cpu_hdr.c_size, 541 dump_off + hdr_size); 542 if (sz != cpu_hdr.c_size) { 543 _kvm_err(kd, kd->program, "size %zu != cpu_hdr.csize %"PRIu32, 544 sz, cpu_hdr.c_size); 545 goto fail; 546 } 547 hdr_size += kd->cpu_dsize; 548 549 /* 550 * Leave phys mem pointer at beginning of memory data 551 */ 552 kd->dump_off = dump_off + hdr_size; 553 if (Lseek(kd, kd->pmfd, kd->dump_off, SEEK_SET) == -1) { 554 _kvm_err(kd, kd->program, "failed to seek to %" PRId64, 555 (int64_t)kd->dump_off); 556 goto fail; 557 } 558 559 /* 560 * Create a kcore_hdr. 561 */ 562 kd->kcore_hdr = _kvm_malloc(kd, sizeof(kcore_hdr_t)); 563 if (kd->kcore_hdr == NULL) { 564 _kvm_err(kd, kd->program, "failed to allocate header"); 565 goto fail; 566 } 567 568 kd->kcore_hdr->c_hdrsize = ALIGN(sizeof(kcore_hdr_t)); 569 kd->kcore_hdr->c_seghdrsize = ALIGN(sizeof(kcore_seg_t)); 570 kd->kcore_hdr->c_nseg = 2; 571 CORE_SETMAGIC(*(kd->kcore_hdr), KCORE_MAGIC, MID_MACHINE,0); 572 573 /* 574 * Now that we have a valid header, enable translations. 575 */ 576 if (_kvm_initvtop(kd) == 0) 577 /* Success */ 578 return (hdr_size); 579 580 fail: 581 if (kd->kcore_hdr != NULL) { 582 free(kd->kcore_hdr); 583 kd->kcore_hdr = NULL; 584 } 585 if (kd->cpu_data != NULL) { 586 free(kd->cpu_data); 587 kd->cpu_data = NULL; 588 kd->cpu_dsize = 0; 589 } 590 return (-1); 591 } 592 593 static int 594 clear_gap(kvm_t *kd, bool (*write_buf)(void *, const void *, size_t), 595 void *cookie, size_t size) 596 { 597 char buf[1024]; 598 size_t len; 599 600 (void)memset(buf, 0, size > sizeof(buf) ? sizeof(buf) : size); 601 602 while (size > 0) { 603 len = size > sizeof(buf) ? sizeof(buf) : size; 604 if (!(*write_buf)(cookie, buf, len)) { 605 _kvm_syserr(kd, kd->program, "clear_gap"); 606 return -1; 607 } 608 size -= len; 609 } 610 611 return 0; 612 } 613 614 /* 615 * Write the dump header by calling write_buf with cookie as first argument. 616 */ 617 int 618 kvm_dump_header(kvm_t *kd, bool (*write_buf)(void *, const void *, size_t), 619 void *cookie, int dumpsize) 620 { 621 kcore_seg_t seghdr; 622 long offset; 623 size_t gap; 624 625 if (kd->kcore_hdr == NULL || kd->cpu_data == NULL) { 626 _kvm_err(kd, kd->program, "no valid dump header(s)"); 627 return (-1); 628 } 629 630 /* 631 * Write the generic header 632 */ 633 offset = 0; 634 if (!(*write_buf)(cookie, kd->kcore_hdr, sizeof(kcore_hdr_t))) { 635 _kvm_syserr(kd, kd->program, "kvm_dump_header"); 636 return (-1); 637 } 638 offset += kd->kcore_hdr->c_hdrsize; 639 gap = kd->kcore_hdr->c_hdrsize - sizeof(kcore_hdr_t); 640 if (clear_gap(kd, write_buf, cookie, gap) == -1) 641 return (-1); 642 643 /* 644 * Write the CPU header 645 */ 646 CORE_SETMAGIC(seghdr, KCORESEG_MAGIC, 0, CORE_CPU); 647 seghdr.c_size = ALIGN(kd->cpu_dsize); 648 if (!(*write_buf)(cookie, &seghdr, sizeof(seghdr))) { 649 _kvm_syserr(kd, kd->program, "kvm_dump_header"); 650 return (-1); 651 } 652 offset += kd->kcore_hdr->c_seghdrsize; 653 gap = kd->kcore_hdr->c_seghdrsize - sizeof(seghdr); 654 if (clear_gap(kd, write_buf, cookie, gap) == -1) 655 return (-1); 656 657 if (!(*write_buf)(cookie, kd->cpu_data, kd->cpu_dsize)) { 658 _kvm_syserr(kd, kd->program, "kvm_dump_header"); 659 return (-1); 660 } 661 offset += seghdr.c_size; 662 gap = seghdr.c_size - kd->cpu_dsize; 663 if (clear_gap(kd, write_buf, cookie, gap) == -1) 664 return (-1); 665 666 /* 667 * Write the actual dump data segment header 668 */ 669 CORE_SETMAGIC(seghdr, KCORESEG_MAGIC, 0, CORE_DATA); 670 seghdr.c_size = dumpsize; 671 if (!(*write_buf)(cookie, &seghdr, sizeof(seghdr))) { 672 _kvm_syserr(kd, kd->program, "kvm_dump_header"); 673 return (-1); 674 } 675 offset += kd->kcore_hdr->c_seghdrsize; 676 gap = kd->kcore_hdr->c_seghdrsize - sizeof(seghdr); 677 if (clear_gap(kd, write_buf, cookie, gap) == -1) 678 return (-1); 679 680 return (int)offset; 681 } 682 683 static bool 684 kvm_dump_header_stdio(void *cookie, const void *buf, size_t len) 685 { 686 return fwrite(buf, len, 1, (FILE *)cookie) == 1; 687 } 688 689 int 690 kvm_dump_wrtheader(kvm_t *kd, FILE *fp, int dumpsize) 691 { 692 return kvm_dump_header(kd, kvm_dump_header_stdio, fp, dumpsize); 693 } 694 695 kvm_t * 696 kvm_openfiles(const char *uf, const char *mf, const char *sf, 697 int flag, char *errout) 698 { 699 kvm_t *kd; 700 701 if ((kd = malloc(sizeof(*kd))) == NULL) { 702 (void)strlcpy(errout, strerror(errno), _POSIX2_LINE_MAX); 703 return (0); 704 } 705 kd->program = 0; 706 return (_kvm_open(kd, uf, mf, sf, flag, errout)); 707 } 708 709 kvm_t * 710 kvm_open(const char *uf, const char *mf, const char *sf, int flag, 711 const char *program) 712 { 713 kvm_t *kd; 714 715 if ((kd = malloc(sizeof(*kd))) == NULL) { 716 (void)fprintf(stderr, "%s: %s\n", 717 program ? program : getprogname(), strerror(errno)); 718 return (0); 719 } 720 kd->program = program; 721 return (_kvm_open(kd, uf, mf, sf, flag, NULL)); 722 } 723 724 int 725 kvm_close(kvm_t *kd) 726 { 727 int error = 0; 728 729 if (kd->pmfd >= 0) 730 error |= close(kd->pmfd); 731 if (kd->vmfd >= 0) 732 error |= close(kd->vmfd); 733 if (kd->nlfd >= 0) 734 error |= close(kd->nlfd); 735 if (kd->swfd >= 0) 736 error |= close(kd->swfd); 737 if (kd->vmst) 738 _kvm_freevtop(kd); 739 kd->cpu_dsize = 0; 740 if (kd->cpu_data != NULL) 741 free(kd->cpu_data); 742 if (kd->kcore_hdr != NULL) 743 free(kd->kcore_hdr); 744 if (kd->procbase != 0) 745 free(kd->procbase); 746 if (kd->procbase2 != 0) 747 free(kd->procbase2); 748 if (kd->lwpbase != 0) 749 free(kd->lwpbase); 750 if (kd->swapspc != 0) 751 free(kd->swapspc); 752 if (kd->argspc != 0) 753 free(kd->argspc); 754 if (kd->argbuf != 0) 755 free(kd->argbuf); 756 if (kd->argv != 0) 757 free(kd->argv); 758 if (kd->iobuf != 0) 759 free(kd->iobuf); 760 free(kd); 761 762 return (error); 763 } 764 765 int 766 kvm_nlist(kvm_t *kd, struct nlist *nl) 767 { 768 int rv, nlfd; 769 770 /* 771 * kd->nlfd might be negative when we get here, and in that 772 * case that means that we're using /dev/ksyms. 773 * So open it again, just for the time we retrieve the list. 774 */ 775 if (kd->nlfd < 0) { 776 nlfd = open(_PATH_KSYMS, O_RDONLY | O_CLOEXEC, 0); 777 if (nlfd < 0) { 778 _kvm_err(kd, 0, "failed to open %s", _PATH_KSYMS); 779 return (nlfd); 780 } 781 } else 782 nlfd = kd->nlfd; 783 784 /* 785 * Call the nlist(3) routines to retrieve the given namelist. 786 */ 787 rv = __fdnlist(nlfd, nl); 788 789 if (rv == -1) 790 _kvm_err(kd, 0, "bad namelist"); 791 792 if (kd->nlfd < 0) 793 close(nlfd); 794 795 return (rv); 796 } 797 798 int 799 kvm_dump_inval(kvm_t *kd) 800 { 801 struct nlist nl[2]; 802 paddr_t pa; 803 size_t dsize; 804 off_t doff; 805 void *newbuf; 806 807 if (ISALIVE(kd)) { 808 _kvm_err(kd, kd->program, "clearing dump on live kernel"); 809 return (-1); 810 } 811 nl[0].n_name = "_dumpmag"; 812 nl[1].n_name = NULL; 813 814 if (kvm_nlist(kd, nl) == -1) { 815 _kvm_err(kd, 0, "bad namelist"); 816 return (-1); 817 } 818 if (_kvm_kvatop(kd, (vaddr_t)nl[0].n_value, &pa) == 0) 819 return (-1); 820 821 errno = 0; 822 dsize = MAX(kd->fdalign, sizeof(u_long)); 823 if (kd->iobufsz < dsize) { 824 newbuf = realloc(kd->iobuf, dsize); 825 if (newbuf == NULL) { 826 _kvm_syserr(kd, 0, "cannot allocate I/O buffer"); 827 return (-1); 828 } 829 kd->iobuf = newbuf; 830 kd->iobufsz = dsize; 831 } 832 memset(kd->iobuf, 0, dsize); 833 doff = _kvm_pa2off(kd, pa); 834 doff -= doff % kd->fdalign; 835 if (pwrite(kd->pmfd, kd->iobuf, dsize, doff) == -1) { 836 _kvm_syserr(kd, 0, "cannot invalidate dump - pwrite"); 837 return (-1); 838 } 839 return (0); 840 } 841 842 ssize_t 843 kvm_read(kvm_t *kd, u_long kva, void *buf, size_t len) 844 { 845 int cc; 846 void *cp; 847 848 if (ISKMEM(kd)) { 849 /* 850 * We're using /dev/kmem. Just read straight from the 851 * device and let the active kernel do the address translation. 852 */ 853 errno = 0; 854 cc = _kvm_pread(kd, kd->vmfd, buf, len, (off_t)kva); 855 if (cc < 0) { 856 _kvm_syserr(kd, 0, "kvm_read"); 857 return (-1); 858 } else if (cc < len) 859 _kvm_err(kd, kd->program, "short read"); 860 return (cc); 861 } else if (ISSYSCTL(kd)) { 862 _kvm_err(kd, kd->program, "kvm_open called with KVM_NO_FILES, " 863 "can't use kvm_read"); 864 return (-1); 865 } else { 866 if ((kd->kcore_hdr == NULL) || (kd->cpu_data == NULL)) { 867 _kvm_err(kd, kd->program, "no valid dump header"); 868 return (-1); 869 } 870 cp = buf; 871 while (len > 0) { 872 paddr_t pa; 873 off_t foff; 874 875 cc = _kvm_kvatop(kd, (vaddr_t)kva, &pa); 876 if (cc == 0) 877 return (-1); 878 if (cc > len) 879 cc = len; 880 foff = _kvm_pa2off(kd, pa); 881 errno = 0; 882 cc = _kvm_pread(kd, kd->pmfd, cp, (size_t)cc, foff); 883 if (cc < 0) { 884 _kvm_syserr(kd, kd->program, "kvm_read"); 885 break; 886 } 887 /* 888 * If kvm_kvatop returns a bogus value or our core 889 * file is truncated, we might wind up seeking beyond 890 * the end of the core file in which case the read will 891 * return 0 (EOF). 892 */ 893 if (cc == 0) 894 break; 895 cp = (char *)cp + cc; 896 kva += cc; 897 len -= cc; 898 } 899 return ((char *)cp - (char *)buf); 900 } 901 /* NOTREACHED */ 902 } 903 904 ssize_t 905 kvm_write(kvm_t *kd, u_long kva, const void *buf, size_t len) 906 { 907 int cc; 908 909 if (ISKMEM(kd)) { 910 /* 911 * Just like kvm_read, only we write. 912 */ 913 errno = 0; 914 cc = pwrite(kd->vmfd, buf, len, (off_t)kva); 915 if (cc < 0) { 916 _kvm_syserr(kd, 0, "kvm_write"); 917 return (-1); 918 } else if (cc < len) 919 _kvm_err(kd, kd->program, "short write"); 920 return (cc); 921 } else if (ISSYSCTL(kd)) { 922 _kvm_err(kd, kd->program, "kvm_open called with KVM_NO_FILES, " 923 "can't use kvm_write"); 924 return (-1); 925 } else { 926 _kvm_err(kd, kd->program, 927 "kvm_write not implemented for dead kernels"); 928 return (-1); 929 } 930 /* NOTREACHED */ 931 } 932