1 /*- 2 * Copyright (c) 2000 David O'Brien 3 * Copyright (c) 1995-1996 Søren Schmidt 4 * Copyright (c) 1996 Peter Wemm 5 * 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 * in this position and unchanged. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. The name of the author may not be used to endorse or promote products 17 * derived from this software without specific prior written permission 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #include <sys/cdefs.h> 32 __FBSDID("$FreeBSD$"); 33 34 #include "opt_capsicum.h" 35 #include "opt_compat.h" 36 #include "opt_core.h" 37 38 #include <sys/param.h> 39 #include <sys/capability.h> 40 #include <sys/exec.h> 41 #include <sys/fcntl.h> 42 #include <sys/imgact.h> 43 #include <sys/imgact_elf.h> 44 #include <sys/kernel.h> 45 #include <sys/lock.h> 46 #include <sys/malloc.h> 47 #include <sys/mount.h> 48 #include <sys/mutex.h> 49 #include <sys/mman.h> 50 #include <sys/namei.h> 51 #include <sys/pioctl.h> 52 #include <sys/proc.h> 53 #include <sys/procfs.h> 54 #include <sys/racct.h> 55 #include <sys/resourcevar.h> 56 #include <sys/sf_buf.h> 57 #include <sys/smp.h> 58 #include <sys/systm.h> 59 #include <sys/signalvar.h> 60 #include <sys/stat.h> 61 #include <sys/sx.h> 62 #include <sys/syscall.h> 63 #include <sys/sysctl.h> 64 #include <sys/sysent.h> 65 #include <sys/vnode.h> 66 #include <sys/syslog.h> 67 #include <sys/eventhandler.h> 68 69 #include <net/zlib.h> 70 71 #include <vm/vm.h> 72 #include <vm/vm_kern.h> 73 #include <vm/vm_param.h> 74 #include <vm/pmap.h> 75 #include <vm/vm_map.h> 76 #include <vm/vm_object.h> 77 #include <vm/vm_extern.h> 78 79 #include <machine/elf.h> 80 #include <machine/md_var.h> 81 82 #define OLD_EI_BRAND 8 83 84 static int __elfN(check_header)(const Elf_Ehdr *hdr); 85 static Elf_Brandinfo *__elfN(get_brandinfo)(struct image_params *imgp, 86 const char *interp, int32_t *osrel); 87 static int __elfN(load_file)(struct proc *p, const char *file, u_long *addr, 88 u_long *entry, size_t pagesize); 89 static int __elfN(load_section)(struct image_params *imgp, vm_offset_t offset, 90 caddr_t vmaddr, size_t memsz, size_t filsz, vm_prot_t prot, 91 size_t pagesize); 92 static int __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp); 93 static boolean_t __elfN(freebsd_trans_osrel)(const Elf_Note *note, 94 int32_t *osrel); 95 static boolean_t kfreebsd_trans_osrel(const Elf_Note *note, int32_t *osrel); 96 static boolean_t __elfN(check_note)(struct image_params *imgp, 97 Elf_Brandnote *checknote, int32_t *osrel); 98 static vm_prot_t __elfN(trans_prot)(Elf_Word); 99 static Elf_Word __elfN(untrans_prot)(vm_prot_t); 100 101 SYSCTL_NODE(_kern, OID_AUTO, __CONCAT(elf, __ELF_WORD_SIZE), CTLFLAG_RW, 0, 102 ""); 103 104 #ifdef COMPRESS_USER_CORES 105 static int compress_core(gzFile, char *, char *, unsigned int, 106 struct thread * td); 107 #define CORE_BUF_SIZE (16 * 1024) 108 #endif 109 110 int __elfN(fallback_brand) = -1; 111 SYSCTL_INT(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO, 112 fallback_brand, CTLFLAG_RW, &__elfN(fallback_brand), 0, 113 __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) " brand of last resort"); 114 TUNABLE_INT("kern.elf" __XSTRING(__ELF_WORD_SIZE) ".fallback_brand", 115 &__elfN(fallback_brand)); 116 117 static int elf_legacy_coredump = 0; 118 SYSCTL_INT(_debug, OID_AUTO, __elfN(legacy_coredump), CTLFLAG_RW, 119 &elf_legacy_coredump, 0, ""); 120 121 int __elfN(nxstack) = 122 #if defined(__amd64__) || defined(__powerpc64__) /* both 64 and 32 bit */ 123 1; 124 #else 125 0; 126 #endif 127 SYSCTL_INT(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO, 128 nxstack, CTLFLAG_RW, &__elfN(nxstack), 0, 129 __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) ": enable non-executable stack"); 130 131 #if __ELF_WORD_SIZE == 32 132 #if defined(__amd64__) || defined(__ia64__) 133 int i386_read_exec = 0; 134 SYSCTL_INT(_kern_elf32, OID_AUTO, read_exec, CTLFLAG_RW, &i386_read_exec, 0, 135 "enable execution from readable segments"); 136 #endif 137 #endif 138 139 static Elf_Brandinfo *elf_brand_list[MAX_BRANDS]; 140 141 #define trunc_page_ps(va, ps) ((va) & ~(ps - 1)) 142 #define round_page_ps(va, ps) (((va) + (ps - 1)) & ~(ps - 1)) 143 #define aligned(a, t) (trunc_page_ps((u_long)(a), sizeof(t)) == (u_long)(a)) 144 145 static const char FREEBSD_ABI_VENDOR[] = "FreeBSD"; 146 147 Elf_Brandnote __elfN(freebsd_brandnote) = { 148 .hdr.n_namesz = sizeof(FREEBSD_ABI_VENDOR), 149 .hdr.n_descsz = sizeof(int32_t), 150 .hdr.n_type = 1, 151 .vendor = FREEBSD_ABI_VENDOR, 152 .flags = BN_TRANSLATE_OSREL, 153 .trans_osrel = __elfN(freebsd_trans_osrel) 154 }; 155 156 static boolean_t 157 __elfN(freebsd_trans_osrel)(const Elf_Note *note, int32_t *osrel) 158 { 159 uintptr_t p; 160 161 p = (uintptr_t)(note + 1); 162 p += roundup2(note->n_namesz, sizeof(Elf32_Addr)); 163 *osrel = *(const int32_t *)(p); 164 165 return (TRUE); 166 } 167 168 static const char GNU_ABI_VENDOR[] = "GNU"; 169 static int GNU_KFREEBSD_ABI_DESC = 3; 170 171 Elf_Brandnote __elfN(kfreebsd_brandnote) = { 172 .hdr.n_namesz = sizeof(GNU_ABI_VENDOR), 173 .hdr.n_descsz = 16, /* XXX at least 16 */ 174 .hdr.n_type = 1, 175 .vendor = GNU_ABI_VENDOR, 176 .flags = BN_TRANSLATE_OSREL, 177 .trans_osrel = kfreebsd_trans_osrel 178 }; 179 180 static boolean_t 181 kfreebsd_trans_osrel(const Elf_Note *note, int32_t *osrel) 182 { 183 const Elf32_Word *desc; 184 uintptr_t p; 185 186 p = (uintptr_t)(note + 1); 187 p += roundup2(note->n_namesz, sizeof(Elf32_Addr)); 188 189 desc = (const Elf32_Word *)p; 190 if (desc[0] != GNU_KFREEBSD_ABI_DESC) 191 return (FALSE); 192 193 /* 194 * Debian GNU/kFreeBSD embed the earliest compatible kernel version 195 * (__FreeBSD_version: <major><two digit minor>Rxx) in the LSB way. 196 */ 197 *osrel = desc[1] * 100000 + desc[2] * 1000 + desc[3]; 198 199 return (TRUE); 200 } 201 202 int 203 __elfN(insert_brand_entry)(Elf_Brandinfo *entry) 204 { 205 int i; 206 207 for (i = 0; i < MAX_BRANDS; i++) { 208 if (elf_brand_list[i] == NULL) { 209 elf_brand_list[i] = entry; 210 break; 211 } 212 } 213 if (i == MAX_BRANDS) { 214 printf("WARNING: %s: could not insert brandinfo entry: %p\n", 215 __func__, entry); 216 return (-1); 217 } 218 return (0); 219 } 220 221 int 222 __elfN(remove_brand_entry)(Elf_Brandinfo *entry) 223 { 224 int i; 225 226 for (i = 0; i < MAX_BRANDS; i++) { 227 if (elf_brand_list[i] == entry) { 228 elf_brand_list[i] = NULL; 229 break; 230 } 231 } 232 if (i == MAX_BRANDS) 233 return (-1); 234 return (0); 235 } 236 237 int 238 __elfN(brand_inuse)(Elf_Brandinfo *entry) 239 { 240 struct proc *p; 241 int rval = FALSE; 242 243 sx_slock(&allproc_lock); 244 FOREACH_PROC_IN_SYSTEM(p) { 245 if (p->p_sysent == entry->sysvec) { 246 rval = TRUE; 247 break; 248 } 249 } 250 sx_sunlock(&allproc_lock); 251 252 return (rval); 253 } 254 255 static Elf_Brandinfo * 256 __elfN(get_brandinfo)(struct image_params *imgp, const char *interp, 257 int32_t *osrel) 258 { 259 const Elf_Ehdr *hdr = (const Elf_Ehdr *)imgp->image_header; 260 Elf_Brandinfo *bi; 261 boolean_t ret; 262 int i; 263 264 /* 265 * We support four types of branding -- (1) the ELF EI_OSABI field 266 * that SCO added to the ELF spec, (2) FreeBSD 3.x's traditional string 267 * branding w/in the ELF header, (3) path of the `interp_path' 268 * field, and (4) the ".note.ABI-tag" ELF section. 269 */ 270 271 /* Look for an ".note.ABI-tag" ELF section */ 272 for (i = 0; i < MAX_BRANDS; i++) { 273 bi = elf_brand_list[i]; 274 if (bi == NULL) 275 continue; 276 if (hdr->e_machine == bi->machine && (bi->flags & 277 (BI_BRAND_NOTE|BI_BRAND_NOTE_MANDATORY)) != 0) { 278 ret = __elfN(check_note)(imgp, bi->brand_note, osrel); 279 if (ret) 280 return (bi); 281 } 282 } 283 284 /* If the executable has a brand, search for it in the brand list. */ 285 for (i = 0; i < MAX_BRANDS; i++) { 286 bi = elf_brand_list[i]; 287 if (bi == NULL || bi->flags & BI_BRAND_NOTE_MANDATORY) 288 continue; 289 if (hdr->e_machine == bi->machine && 290 (hdr->e_ident[EI_OSABI] == bi->brand || 291 strncmp((const char *)&hdr->e_ident[OLD_EI_BRAND], 292 bi->compat_3_brand, strlen(bi->compat_3_brand)) == 0)) 293 return (bi); 294 } 295 296 /* Lacking a known brand, search for a recognized interpreter. */ 297 if (interp != NULL) { 298 for (i = 0; i < MAX_BRANDS; i++) { 299 bi = elf_brand_list[i]; 300 if (bi == NULL || bi->flags & BI_BRAND_NOTE_MANDATORY) 301 continue; 302 if (hdr->e_machine == bi->machine && 303 strcmp(interp, bi->interp_path) == 0) 304 return (bi); 305 } 306 } 307 308 /* Lacking a recognized interpreter, try the default brand */ 309 for (i = 0; i < MAX_BRANDS; i++) { 310 bi = elf_brand_list[i]; 311 if (bi == NULL || bi->flags & BI_BRAND_NOTE_MANDATORY) 312 continue; 313 if (hdr->e_machine == bi->machine && 314 __elfN(fallback_brand) == bi->brand) 315 return (bi); 316 } 317 return (NULL); 318 } 319 320 static int 321 __elfN(check_header)(const Elf_Ehdr *hdr) 322 { 323 Elf_Brandinfo *bi; 324 int i; 325 326 if (!IS_ELF(*hdr) || 327 hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS || 328 hdr->e_ident[EI_DATA] != ELF_TARG_DATA || 329 hdr->e_ident[EI_VERSION] != EV_CURRENT || 330 hdr->e_phentsize != sizeof(Elf_Phdr) || 331 hdr->e_version != ELF_TARG_VER) 332 return (ENOEXEC); 333 334 /* 335 * Make sure we have at least one brand for this machine. 336 */ 337 338 for (i = 0; i < MAX_BRANDS; i++) { 339 bi = elf_brand_list[i]; 340 if (bi != NULL && bi->machine == hdr->e_machine) 341 break; 342 } 343 if (i == MAX_BRANDS) 344 return (ENOEXEC); 345 346 return (0); 347 } 348 349 static int 350 __elfN(map_partial)(vm_map_t map, vm_object_t object, vm_ooffset_t offset, 351 vm_offset_t start, vm_offset_t end, vm_prot_t prot) 352 { 353 struct sf_buf *sf; 354 int error; 355 vm_offset_t off; 356 357 /* 358 * Create the page if it doesn't exist yet. Ignore errors. 359 */ 360 vm_map_lock(map); 361 vm_map_insert(map, NULL, 0, trunc_page(start), round_page(end), 362 VM_PROT_ALL, VM_PROT_ALL, 0); 363 vm_map_unlock(map); 364 365 /* 366 * Find the page from the underlying object. 367 */ 368 if (object) { 369 sf = vm_imgact_map_page(object, offset); 370 if (sf == NULL) 371 return (KERN_FAILURE); 372 off = offset - trunc_page(offset); 373 error = copyout((caddr_t)sf_buf_kva(sf) + off, (caddr_t)start, 374 end - start); 375 vm_imgact_unmap_page(sf); 376 if (error) { 377 return (KERN_FAILURE); 378 } 379 } 380 381 return (KERN_SUCCESS); 382 } 383 384 static int 385 __elfN(map_insert)(vm_map_t map, vm_object_t object, vm_ooffset_t offset, 386 vm_offset_t start, vm_offset_t end, vm_prot_t prot, int cow) 387 { 388 struct sf_buf *sf; 389 vm_offset_t off; 390 vm_size_t sz; 391 int error, rv; 392 393 if (start != trunc_page(start)) { 394 rv = __elfN(map_partial)(map, object, offset, start, 395 round_page(start), prot); 396 if (rv) 397 return (rv); 398 offset += round_page(start) - start; 399 start = round_page(start); 400 } 401 if (end != round_page(end)) { 402 rv = __elfN(map_partial)(map, object, offset + 403 trunc_page(end) - start, trunc_page(end), end, prot); 404 if (rv) 405 return (rv); 406 end = trunc_page(end); 407 } 408 if (end > start) { 409 if (offset & PAGE_MASK) { 410 /* 411 * The mapping is not page aligned. This means we have 412 * to copy the data. Sigh. 413 */ 414 rv = vm_map_find(map, NULL, 0, &start, end - start, 415 FALSE, prot | VM_PROT_WRITE, VM_PROT_ALL, 0); 416 if (rv) 417 return (rv); 418 if (object == NULL) 419 return (KERN_SUCCESS); 420 for (; start < end; start += sz) { 421 sf = vm_imgact_map_page(object, offset); 422 if (sf == NULL) 423 return (KERN_FAILURE); 424 off = offset - trunc_page(offset); 425 sz = end - start; 426 if (sz > PAGE_SIZE - off) 427 sz = PAGE_SIZE - off; 428 error = copyout((caddr_t)sf_buf_kva(sf) + off, 429 (caddr_t)start, sz); 430 vm_imgact_unmap_page(sf); 431 if (error) { 432 return (KERN_FAILURE); 433 } 434 offset += sz; 435 } 436 rv = KERN_SUCCESS; 437 } else { 438 vm_object_reference(object); 439 vm_map_lock(map); 440 rv = vm_map_insert(map, object, offset, start, end, 441 prot, VM_PROT_ALL, cow); 442 vm_map_unlock(map); 443 if (rv != KERN_SUCCESS) 444 vm_object_deallocate(object); 445 } 446 return (rv); 447 } else { 448 return (KERN_SUCCESS); 449 } 450 } 451 452 static int 453 __elfN(load_section)(struct image_params *imgp, vm_offset_t offset, 454 caddr_t vmaddr, size_t memsz, size_t filsz, vm_prot_t prot, 455 size_t pagesize) 456 { 457 struct sf_buf *sf; 458 size_t map_len; 459 vm_map_t map; 460 vm_object_t object; 461 vm_offset_t map_addr; 462 int error, rv, cow; 463 size_t copy_len; 464 vm_offset_t file_addr; 465 466 /* 467 * It's necessary to fail if the filsz + offset taken from the 468 * header is greater than the actual file pager object's size. 469 * If we were to allow this, then the vm_map_find() below would 470 * walk right off the end of the file object and into the ether. 471 * 472 * While I'm here, might as well check for something else that 473 * is invalid: filsz cannot be greater than memsz. 474 */ 475 if ((off_t)filsz + offset > imgp->attr->va_size || filsz > memsz) { 476 uprintf("elf_load_section: truncated ELF file\n"); 477 return (ENOEXEC); 478 } 479 480 object = imgp->object; 481 map = &imgp->proc->p_vmspace->vm_map; 482 map_addr = trunc_page_ps((vm_offset_t)vmaddr, pagesize); 483 file_addr = trunc_page_ps(offset, pagesize); 484 485 /* 486 * We have two choices. We can either clear the data in the last page 487 * of an oversized mapping, or we can start the anon mapping a page 488 * early and copy the initialized data into that first page. We 489 * choose the second.. 490 */ 491 if (memsz > filsz) 492 map_len = trunc_page_ps(offset + filsz, pagesize) - file_addr; 493 else 494 map_len = round_page_ps(offset + filsz, pagesize) - file_addr; 495 496 if (map_len != 0) { 497 /* cow flags: don't dump readonly sections in core */ 498 cow = MAP_COPY_ON_WRITE | MAP_PREFAULT | 499 (prot & VM_PROT_WRITE ? 0 : MAP_DISABLE_COREDUMP); 500 501 rv = __elfN(map_insert)(map, 502 object, 503 file_addr, /* file offset */ 504 map_addr, /* virtual start */ 505 map_addr + map_len,/* virtual end */ 506 prot, 507 cow); 508 if (rv != KERN_SUCCESS) 509 return (EINVAL); 510 511 /* we can stop now if we've covered it all */ 512 if (memsz == filsz) { 513 return (0); 514 } 515 } 516 517 518 /* 519 * We have to get the remaining bit of the file into the first part 520 * of the oversized map segment. This is normally because the .data 521 * segment in the file is extended to provide bss. It's a neat idea 522 * to try and save a page, but it's a pain in the behind to implement. 523 */ 524 copy_len = (offset + filsz) - trunc_page_ps(offset + filsz, pagesize); 525 map_addr = trunc_page_ps((vm_offset_t)vmaddr + filsz, pagesize); 526 map_len = round_page_ps((vm_offset_t)vmaddr + memsz, pagesize) - 527 map_addr; 528 529 /* This had damn well better be true! */ 530 if (map_len != 0) { 531 rv = __elfN(map_insert)(map, NULL, 0, map_addr, map_addr + 532 map_len, VM_PROT_ALL, 0); 533 if (rv != KERN_SUCCESS) { 534 return (EINVAL); 535 } 536 } 537 538 if (copy_len != 0) { 539 vm_offset_t off; 540 541 sf = vm_imgact_map_page(object, offset + filsz); 542 if (sf == NULL) 543 return (EIO); 544 545 /* send the page fragment to user space */ 546 off = trunc_page_ps(offset + filsz, pagesize) - 547 trunc_page(offset + filsz); 548 error = copyout((caddr_t)sf_buf_kva(sf) + off, 549 (caddr_t)map_addr, copy_len); 550 vm_imgact_unmap_page(sf); 551 if (error) { 552 return (error); 553 } 554 } 555 556 /* 557 * set it to the specified protection. 558 * XXX had better undo the damage from pasting over the cracks here! 559 */ 560 vm_map_protect(map, trunc_page(map_addr), round_page(map_addr + 561 map_len), prot, FALSE); 562 563 return (0); 564 } 565 566 /* 567 * Load the file "file" into memory. It may be either a shared object 568 * or an executable. 569 * 570 * The "addr" reference parameter is in/out. On entry, it specifies 571 * the address where a shared object should be loaded. If the file is 572 * an executable, this value is ignored. On exit, "addr" specifies 573 * where the file was actually loaded. 574 * 575 * The "entry" reference parameter is out only. On exit, it specifies 576 * the entry point for the loaded file. 577 */ 578 static int 579 __elfN(load_file)(struct proc *p, const char *file, u_long *addr, 580 u_long *entry, size_t pagesize) 581 { 582 struct { 583 struct nameidata nd; 584 struct vattr attr; 585 struct image_params image_params; 586 } *tempdata; 587 const Elf_Ehdr *hdr = NULL; 588 const Elf_Phdr *phdr = NULL; 589 struct nameidata *nd; 590 struct vattr *attr; 591 struct image_params *imgp; 592 vm_prot_t prot; 593 u_long rbase; 594 u_long base_addr = 0; 595 int vfslocked, error, i, numsegs; 596 597 #ifdef CAPABILITY_MODE 598 /* 599 * XXXJA: This check can go away once we are sufficiently confident 600 * that the checks in namei() are correct. 601 */ 602 if (IN_CAPABILITY_MODE(curthread)) 603 return (ECAPMODE); 604 #endif 605 606 tempdata = malloc(sizeof(*tempdata), M_TEMP, M_WAITOK); 607 nd = &tempdata->nd; 608 attr = &tempdata->attr; 609 imgp = &tempdata->image_params; 610 611 /* 612 * Initialize part of the common data 613 */ 614 imgp->proc = p; 615 imgp->attr = attr; 616 imgp->firstpage = NULL; 617 imgp->image_header = NULL; 618 imgp->object = NULL; 619 imgp->execlabel = NULL; 620 621 NDINIT(nd, LOOKUP, MPSAFE|LOCKLEAF|FOLLOW, UIO_SYSSPACE, file, 622 curthread); 623 vfslocked = 0; 624 if ((error = namei(nd)) != 0) { 625 nd->ni_vp = NULL; 626 goto fail; 627 } 628 vfslocked = NDHASGIANT(nd); 629 NDFREE(nd, NDF_ONLY_PNBUF); 630 imgp->vp = nd->ni_vp; 631 632 /* 633 * Check permissions, modes, uid, etc on the file, and "open" it. 634 */ 635 error = exec_check_permissions(imgp); 636 if (error) 637 goto fail; 638 639 error = exec_map_first_page(imgp); 640 if (error) 641 goto fail; 642 643 /* 644 * Also make certain that the interpreter stays the same, so set 645 * its VV_TEXT flag, too. 646 */ 647 nd->ni_vp->v_vflag |= VV_TEXT; 648 649 imgp->object = nd->ni_vp->v_object; 650 651 hdr = (const Elf_Ehdr *)imgp->image_header; 652 if ((error = __elfN(check_header)(hdr)) != 0) 653 goto fail; 654 if (hdr->e_type == ET_DYN) 655 rbase = *addr; 656 else if (hdr->e_type == ET_EXEC) 657 rbase = 0; 658 else { 659 error = ENOEXEC; 660 goto fail; 661 } 662 663 /* Only support headers that fit within first page for now */ 664 /* (multiplication of two Elf_Half fields will not overflow) */ 665 if ((hdr->e_phoff > PAGE_SIZE) || 666 (hdr->e_phentsize * hdr->e_phnum) > PAGE_SIZE - hdr->e_phoff) { 667 error = ENOEXEC; 668 goto fail; 669 } 670 671 phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff); 672 if (!aligned(phdr, Elf_Addr)) { 673 error = ENOEXEC; 674 goto fail; 675 } 676 677 for (i = 0, numsegs = 0; i < hdr->e_phnum; i++) { 678 if (phdr[i].p_type == PT_LOAD && phdr[i].p_memsz != 0) { 679 /* Loadable segment */ 680 prot = __elfN(trans_prot)(phdr[i].p_flags); 681 error = __elfN(load_section)(imgp, phdr[i].p_offset, 682 (caddr_t)(uintptr_t)phdr[i].p_vaddr + rbase, 683 phdr[i].p_memsz, phdr[i].p_filesz, prot, pagesize); 684 if (error != 0) 685 goto fail; 686 /* 687 * Establish the base address if this is the 688 * first segment. 689 */ 690 if (numsegs == 0) 691 base_addr = trunc_page(phdr[i].p_vaddr + 692 rbase); 693 numsegs++; 694 } 695 } 696 *addr = base_addr; 697 *entry = (unsigned long)hdr->e_entry + rbase; 698 699 fail: 700 if (imgp->firstpage) 701 exec_unmap_first_page(imgp); 702 703 if (nd->ni_vp) 704 vput(nd->ni_vp); 705 706 VFS_UNLOCK_GIANT(vfslocked); 707 free(tempdata, M_TEMP); 708 709 return (error); 710 } 711 712 static int 713 __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp) 714 { 715 const Elf_Ehdr *hdr = (const Elf_Ehdr *)imgp->image_header; 716 const Elf_Phdr *phdr; 717 Elf_Auxargs *elf_auxargs; 718 struct vmspace *vmspace; 719 vm_prot_t prot; 720 u_long text_size = 0, data_size = 0, total_size = 0; 721 u_long text_addr = 0, data_addr = 0; 722 u_long seg_size, seg_addr; 723 u_long addr, baddr, et_dyn_addr, entry = 0, proghdr = 0; 724 int32_t osrel = 0; 725 int error = 0, i, n; 726 const char *interp = NULL, *newinterp = NULL; 727 Elf_Brandinfo *brand_info; 728 char *path; 729 struct sysentvec *sv; 730 731 /* 732 * Do we have a valid ELF header ? 733 * 734 * Only allow ET_EXEC & ET_DYN here, reject ET_DYN later 735 * if particular brand doesn't support it. 736 */ 737 if (__elfN(check_header)(hdr) != 0 || 738 (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN)) 739 return (-1); 740 741 /* 742 * From here on down, we return an errno, not -1, as we've 743 * detected an ELF file. 744 */ 745 746 if ((hdr->e_phoff > PAGE_SIZE) || 747 (hdr->e_phoff + hdr->e_phentsize * hdr->e_phnum) > PAGE_SIZE) { 748 /* Only support headers in first page for now */ 749 return (ENOEXEC); 750 } 751 phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff); 752 if (!aligned(phdr, Elf_Addr)) 753 return (ENOEXEC); 754 n = 0; 755 baddr = 0; 756 for (i = 0; i < hdr->e_phnum; i++) { 757 switch (phdr[i].p_type) { 758 case PT_LOAD: 759 if (n == 0) 760 baddr = phdr[i].p_vaddr; 761 n++; 762 break; 763 case PT_INTERP: 764 /* Path to interpreter */ 765 if (phdr[i].p_filesz > MAXPATHLEN || 766 phdr[i].p_offset + phdr[i].p_filesz > PAGE_SIZE) 767 return (ENOEXEC); 768 interp = imgp->image_header + phdr[i].p_offset; 769 break; 770 case PT_GNU_STACK: 771 if (__elfN(nxstack)) 772 imgp->stack_prot = 773 __elfN(trans_prot)(phdr[i].p_flags); 774 break; 775 } 776 } 777 778 brand_info = __elfN(get_brandinfo)(imgp, interp, &osrel); 779 if (brand_info == NULL) { 780 uprintf("ELF binary type \"%u\" not known.\n", 781 hdr->e_ident[EI_OSABI]); 782 return (ENOEXEC); 783 } 784 if (hdr->e_type == ET_DYN) { 785 if ((brand_info->flags & BI_CAN_EXEC_DYN) == 0) 786 return (ENOEXEC); 787 /* 788 * Honour the base load address from the dso if it is 789 * non-zero for some reason. 790 */ 791 if (baddr == 0) 792 et_dyn_addr = ET_DYN_LOAD_ADDR; 793 else 794 et_dyn_addr = 0; 795 } else 796 et_dyn_addr = 0; 797 sv = brand_info->sysvec; 798 if (interp != NULL && brand_info->interp_newpath != NULL) 799 newinterp = brand_info->interp_newpath; 800 801 /* 802 * Avoid a possible deadlock if the current address space is destroyed 803 * and that address space maps the locked vnode. In the common case, 804 * the locked vnode's v_usecount is decremented but remains greater 805 * than zero. Consequently, the vnode lock is not needed by vrele(). 806 * However, in cases where the vnode lock is external, such as nullfs, 807 * v_usecount may become zero. 808 * 809 * The VV_TEXT flag prevents modifications to the executable while 810 * the vnode is unlocked. 811 */ 812 VOP_UNLOCK(imgp->vp, 0); 813 814 error = exec_new_vmspace(imgp, sv); 815 imgp->proc->p_sysent = sv; 816 817 vn_lock(imgp->vp, LK_EXCLUSIVE | LK_RETRY); 818 if (error) 819 return (error); 820 821 for (i = 0; i < hdr->e_phnum; i++) { 822 switch (phdr[i].p_type) { 823 case PT_LOAD: /* Loadable segment */ 824 if (phdr[i].p_memsz == 0) 825 break; 826 prot = __elfN(trans_prot)(phdr[i].p_flags); 827 828 #if defined(__ia64__) && __ELF_WORD_SIZE == 32 && defined(IA32_ME_HARDER) 829 /* 830 * Some x86 binaries assume read == executable, 831 * notably the M3 runtime and therefore cvsup 832 */ 833 if (prot & VM_PROT_READ) 834 prot |= VM_PROT_EXECUTE; 835 #endif 836 837 error = __elfN(load_section)(imgp, phdr[i].p_offset, 838 (caddr_t)(uintptr_t)phdr[i].p_vaddr + et_dyn_addr, 839 phdr[i].p_memsz, phdr[i].p_filesz, prot, 840 sv->sv_pagesize); 841 if (error != 0) 842 return (error); 843 844 /* 845 * If this segment contains the program headers, 846 * remember their virtual address for the AT_PHDR 847 * aux entry. Static binaries don't usually include 848 * a PT_PHDR entry. 849 */ 850 if (phdr[i].p_offset == 0 && 851 hdr->e_phoff + hdr->e_phnum * hdr->e_phentsize 852 <= phdr[i].p_filesz) 853 proghdr = phdr[i].p_vaddr + hdr->e_phoff + 854 et_dyn_addr; 855 856 seg_addr = trunc_page(phdr[i].p_vaddr + et_dyn_addr); 857 seg_size = round_page(phdr[i].p_memsz + 858 phdr[i].p_vaddr + et_dyn_addr - seg_addr); 859 860 /* 861 * Make the largest executable segment the official 862 * text segment and all others data. 863 * 864 * Note that obreak() assumes that data_addr + 865 * data_size == end of data load area, and the ELF 866 * file format expects segments to be sorted by 867 * address. If multiple data segments exist, the 868 * last one will be used. 869 */ 870 871 if (phdr[i].p_flags & PF_X && text_size < seg_size) { 872 text_size = seg_size; 873 text_addr = seg_addr; 874 } else { 875 data_size = seg_size; 876 data_addr = seg_addr; 877 } 878 total_size += seg_size; 879 break; 880 case PT_PHDR: /* Program header table info */ 881 proghdr = phdr[i].p_vaddr + et_dyn_addr; 882 break; 883 default: 884 break; 885 } 886 } 887 888 if (data_addr == 0 && data_size == 0) { 889 data_addr = text_addr; 890 data_size = text_size; 891 } 892 893 entry = (u_long)hdr->e_entry + et_dyn_addr; 894 895 /* 896 * Check limits. It should be safe to check the 897 * limits after loading the segments since we do 898 * not actually fault in all the segments pages. 899 */ 900 PROC_LOCK(imgp->proc); 901 if (data_size > lim_cur(imgp->proc, RLIMIT_DATA) || 902 text_size > maxtsiz || 903 total_size > lim_cur(imgp->proc, RLIMIT_VMEM) || 904 racct_set(imgp->proc, RACCT_DATA, data_size) != 0 || 905 racct_set(imgp->proc, RACCT_VMEM, total_size) != 0) { 906 PROC_UNLOCK(imgp->proc); 907 return (ENOMEM); 908 } 909 910 vmspace = imgp->proc->p_vmspace; 911 vmspace->vm_tsize = text_size >> PAGE_SHIFT; 912 vmspace->vm_taddr = (caddr_t)(uintptr_t)text_addr; 913 vmspace->vm_dsize = data_size >> PAGE_SHIFT; 914 vmspace->vm_daddr = (caddr_t)(uintptr_t)data_addr; 915 916 /* 917 * We load the dynamic linker where a userland call 918 * to mmap(0, ...) would put it. The rationale behind this 919 * calculation is that it leaves room for the heap to grow to 920 * its maximum allowed size. 921 */ 922 addr = round_page((vm_offset_t)vmspace->vm_daddr + lim_max(imgp->proc, 923 RLIMIT_DATA)); 924 PROC_UNLOCK(imgp->proc); 925 926 imgp->entry_addr = entry; 927 928 if (interp != NULL) { 929 int have_interp = FALSE; 930 VOP_UNLOCK(imgp->vp, 0); 931 if (brand_info->emul_path != NULL && 932 brand_info->emul_path[0] != '\0') { 933 path = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 934 snprintf(path, MAXPATHLEN, "%s%s", 935 brand_info->emul_path, interp); 936 error = __elfN(load_file)(imgp->proc, path, &addr, 937 &imgp->entry_addr, sv->sv_pagesize); 938 free(path, M_TEMP); 939 if (error == 0) 940 have_interp = TRUE; 941 } 942 if (!have_interp && newinterp != NULL) { 943 error = __elfN(load_file)(imgp->proc, newinterp, &addr, 944 &imgp->entry_addr, sv->sv_pagesize); 945 if (error == 0) 946 have_interp = TRUE; 947 } 948 if (!have_interp) { 949 error = __elfN(load_file)(imgp->proc, interp, &addr, 950 &imgp->entry_addr, sv->sv_pagesize); 951 } 952 vn_lock(imgp->vp, LK_EXCLUSIVE | LK_RETRY); 953 if (error != 0) { 954 uprintf("ELF interpreter %s not found\n", interp); 955 return (error); 956 } 957 } else 958 addr = et_dyn_addr; 959 960 /* 961 * Construct auxargs table (used by the fixup routine) 962 */ 963 elf_auxargs = malloc(sizeof(Elf_Auxargs), M_TEMP, M_WAITOK); 964 elf_auxargs->execfd = -1; 965 elf_auxargs->phdr = proghdr; 966 elf_auxargs->phent = hdr->e_phentsize; 967 elf_auxargs->phnum = hdr->e_phnum; 968 elf_auxargs->pagesz = PAGE_SIZE; 969 elf_auxargs->base = addr; 970 elf_auxargs->flags = 0; 971 elf_auxargs->entry = entry; 972 973 imgp->auxargs = elf_auxargs; 974 imgp->interpreted = 0; 975 imgp->reloc_base = addr; 976 imgp->proc->p_osrel = osrel; 977 978 return (error); 979 } 980 981 #define suword __CONCAT(suword, __ELF_WORD_SIZE) 982 983 int 984 __elfN(freebsd_fixup)(register_t **stack_base, struct image_params *imgp) 985 { 986 Elf_Auxargs *args = (Elf_Auxargs *)imgp->auxargs; 987 Elf_Addr *base; 988 Elf_Addr *pos; 989 990 base = (Elf_Addr *)*stack_base; 991 pos = base + (imgp->args->argc + imgp->args->envc + 2); 992 993 if (args->execfd != -1) 994 AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd); 995 AUXARGS_ENTRY(pos, AT_PHDR, args->phdr); 996 AUXARGS_ENTRY(pos, AT_PHENT, args->phent); 997 AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum); 998 AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz); 999 AUXARGS_ENTRY(pos, AT_FLAGS, args->flags); 1000 AUXARGS_ENTRY(pos, AT_ENTRY, args->entry); 1001 AUXARGS_ENTRY(pos, AT_BASE, args->base); 1002 if (imgp->execpathp != 0) 1003 AUXARGS_ENTRY(pos, AT_EXECPATH, imgp->execpathp); 1004 AUXARGS_ENTRY(pos, AT_OSRELDATE, osreldate); 1005 if (imgp->canary != 0) { 1006 AUXARGS_ENTRY(pos, AT_CANARY, imgp->canary); 1007 AUXARGS_ENTRY(pos, AT_CANARYLEN, imgp->canarylen); 1008 } 1009 AUXARGS_ENTRY(pos, AT_NCPUS, mp_ncpus); 1010 if (imgp->pagesizes != 0) { 1011 AUXARGS_ENTRY(pos, AT_PAGESIZES, imgp->pagesizes); 1012 AUXARGS_ENTRY(pos, AT_PAGESIZESLEN, imgp->pagesizeslen); 1013 } 1014 AUXARGS_ENTRY(pos, AT_STACKPROT, imgp->sysent->sv_shared_page_obj 1015 != NULL && imgp->stack_prot != 0 ? imgp->stack_prot : 1016 imgp->sysent->sv_stackprot); 1017 AUXARGS_ENTRY(pos, AT_NULL, 0); 1018 1019 free(imgp->auxargs, M_TEMP); 1020 imgp->auxargs = NULL; 1021 1022 base--; 1023 suword(base, (long)imgp->args->argc); 1024 *stack_base = (register_t *)base; 1025 return (0); 1026 } 1027 1028 /* 1029 * Code for generating ELF core dumps. 1030 */ 1031 1032 typedef void (*segment_callback)(vm_map_entry_t, void *); 1033 1034 /* Closure for cb_put_phdr(). */ 1035 struct phdr_closure { 1036 Elf_Phdr *phdr; /* Program header to fill in */ 1037 Elf_Off offset; /* Offset of segment in core file */ 1038 }; 1039 1040 /* Closure for cb_size_segment(). */ 1041 struct sseg_closure { 1042 int count; /* Count of writable segments. */ 1043 size_t size; /* Total size of all writable segments. */ 1044 }; 1045 1046 static void cb_put_phdr(vm_map_entry_t, void *); 1047 static void cb_size_segment(vm_map_entry_t, void *); 1048 static void each_writable_segment(struct thread *, segment_callback, void *); 1049 static int __elfN(corehdr)(struct thread *, struct vnode *, struct ucred *, 1050 int, void *, size_t, gzFile); 1051 static void __elfN(puthdr)(struct thread *, void *, size_t *, int); 1052 static void __elfN(putnote)(void *, size_t *, const char *, int, 1053 const void *, size_t); 1054 1055 #ifdef COMPRESS_USER_CORES 1056 extern int compress_user_cores; 1057 extern int compress_user_cores_gzlevel; 1058 #endif 1059 1060 static int 1061 core_output(struct vnode *vp, void *base, size_t len, off_t offset, 1062 struct ucred *active_cred, struct ucred *file_cred, 1063 struct thread *td, char *core_buf, gzFile gzfile) { 1064 1065 int error; 1066 if (gzfile) { 1067 #ifdef COMPRESS_USER_CORES 1068 error = compress_core(gzfile, base, core_buf, len, td); 1069 #else 1070 panic("shouldn't be here"); 1071 #endif 1072 } else { 1073 error = vn_rdwr_inchunks(UIO_WRITE, vp, base, len, offset, 1074 UIO_USERSPACE, IO_UNIT | IO_DIRECT, active_cred, file_cred, 1075 NULL, td); 1076 } 1077 return (error); 1078 } 1079 1080 int 1081 __elfN(coredump)(struct thread *td, struct vnode *vp, off_t limit, int flags) 1082 { 1083 struct ucred *cred = td->td_ucred; 1084 int error = 0; 1085 struct sseg_closure seginfo; 1086 void *hdr; 1087 size_t hdrsize; 1088 1089 gzFile gzfile = Z_NULL; 1090 char *core_buf = NULL; 1091 #ifdef COMPRESS_USER_CORES 1092 char gzopen_flags[8]; 1093 char *p; 1094 int doing_compress = flags & IMGACT_CORE_COMPRESS; 1095 #endif 1096 1097 hdr = NULL; 1098 1099 #ifdef COMPRESS_USER_CORES 1100 if (doing_compress) { 1101 p = gzopen_flags; 1102 *p++ = 'w'; 1103 if (compress_user_cores_gzlevel >= 0 && 1104 compress_user_cores_gzlevel <= 9) 1105 *p++ = '0' + compress_user_cores_gzlevel; 1106 *p = 0; 1107 gzfile = gz_open("", gzopen_flags, vp); 1108 if (gzfile == Z_NULL) { 1109 error = EFAULT; 1110 goto done; 1111 } 1112 core_buf = malloc(CORE_BUF_SIZE, M_TEMP, M_WAITOK | M_ZERO); 1113 if (!core_buf) { 1114 error = ENOMEM; 1115 goto done; 1116 } 1117 } 1118 #endif 1119 1120 /* Size the program segments. */ 1121 seginfo.count = 0; 1122 seginfo.size = 0; 1123 each_writable_segment(td, cb_size_segment, &seginfo); 1124 1125 /* 1126 * Calculate the size of the core file header area by making 1127 * a dry run of generating it. Nothing is written, but the 1128 * size is calculated. 1129 */ 1130 hdrsize = 0; 1131 __elfN(puthdr)(td, (void *)NULL, &hdrsize, seginfo.count); 1132 1133 #ifdef RACCT 1134 PROC_LOCK(td->td_proc); 1135 error = racct_add(td->td_proc, RACCT_CORE, hdrsize + seginfo.size); 1136 PROC_UNLOCK(td->td_proc); 1137 if (error != 0) { 1138 error = EFAULT; 1139 goto done; 1140 } 1141 #endif 1142 if (hdrsize + seginfo.size >= limit) { 1143 error = EFAULT; 1144 goto done; 1145 } 1146 1147 /* 1148 * Allocate memory for building the header, fill it up, 1149 * and write it out. 1150 */ 1151 hdr = malloc(hdrsize, M_TEMP, M_WAITOK); 1152 if (hdr == NULL) { 1153 error = EINVAL; 1154 goto done; 1155 } 1156 error = __elfN(corehdr)(td, vp, cred, seginfo.count, hdr, hdrsize, 1157 gzfile); 1158 1159 /* Write the contents of all of the writable segments. */ 1160 if (error == 0) { 1161 Elf_Phdr *php; 1162 off_t offset; 1163 int i; 1164 1165 php = (Elf_Phdr *)((char *)hdr + sizeof(Elf_Ehdr)) + 1; 1166 offset = hdrsize; 1167 for (i = 0; i < seginfo.count; i++) { 1168 error = core_output(vp, (caddr_t)(uintptr_t)php->p_vaddr, 1169 php->p_filesz, offset, cred, NOCRED, curthread, core_buf, gzfile); 1170 if (error != 0) 1171 break; 1172 offset += php->p_filesz; 1173 php++; 1174 } 1175 } 1176 if (error) { 1177 log(LOG_WARNING, 1178 "Failed to write core file for process %s (error %d)\n", 1179 curproc->p_comm, error); 1180 } 1181 1182 done: 1183 #ifdef COMPRESS_USER_CORES 1184 if (core_buf) 1185 free(core_buf, M_TEMP); 1186 if (gzfile) 1187 gzclose(gzfile); 1188 #endif 1189 1190 free(hdr, M_TEMP); 1191 1192 return (error); 1193 } 1194 1195 /* 1196 * A callback for each_writable_segment() to write out the segment's 1197 * program header entry. 1198 */ 1199 static void 1200 cb_put_phdr(entry, closure) 1201 vm_map_entry_t entry; 1202 void *closure; 1203 { 1204 struct phdr_closure *phc = (struct phdr_closure *)closure; 1205 Elf_Phdr *phdr = phc->phdr; 1206 1207 phc->offset = round_page(phc->offset); 1208 1209 phdr->p_type = PT_LOAD; 1210 phdr->p_offset = phc->offset; 1211 phdr->p_vaddr = entry->start; 1212 phdr->p_paddr = 0; 1213 phdr->p_filesz = phdr->p_memsz = entry->end - entry->start; 1214 phdr->p_align = PAGE_SIZE; 1215 phdr->p_flags = __elfN(untrans_prot)(entry->protection); 1216 1217 phc->offset += phdr->p_filesz; 1218 phc->phdr++; 1219 } 1220 1221 /* 1222 * A callback for each_writable_segment() to gather information about 1223 * the number of segments and their total size. 1224 */ 1225 static void 1226 cb_size_segment(entry, closure) 1227 vm_map_entry_t entry; 1228 void *closure; 1229 { 1230 struct sseg_closure *ssc = (struct sseg_closure *)closure; 1231 1232 ssc->count++; 1233 ssc->size += entry->end - entry->start; 1234 } 1235 1236 /* 1237 * For each writable segment in the process's memory map, call the given 1238 * function with a pointer to the map entry and some arbitrary 1239 * caller-supplied data. 1240 */ 1241 static void 1242 each_writable_segment(td, func, closure) 1243 struct thread *td; 1244 segment_callback func; 1245 void *closure; 1246 { 1247 struct proc *p = td->td_proc; 1248 vm_map_t map = &p->p_vmspace->vm_map; 1249 vm_map_entry_t entry; 1250 vm_object_t backing_object, object; 1251 boolean_t ignore_entry; 1252 1253 vm_map_lock_read(map); 1254 for (entry = map->header.next; entry != &map->header; 1255 entry = entry->next) { 1256 /* 1257 * Don't dump inaccessible mappings, deal with legacy 1258 * coredump mode. 1259 * 1260 * Note that read-only segments related to the elf binary 1261 * are marked MAP_ENTRY_NOCOREDUMP now so we no longer 1262 * need to arbitrarily ignore such segments. 1263 */ 1264 if (elf_legacy_coredump) { 1265 if ((entry->protection & VM_PROT_RW) != VM_PROT_RW) 1266 continue; 1267 } else { 1268 if ((entry->protection & VM_PROT_ALL) == 0) 1269 continue; 1270 } 1271 1272 /* 1273 * Dont include memory segment in the coredump if 1274 * MAP_NOCORE is set in mmap(2) or MADV_NOCORE in 1275 * madvise(2). Do not dump submaps (i.e. parts of the 1276 * kernel map). 1277 */ 1278 if (entry->eflags & (MAP_ENTRY_NOCOREDUMP|MAP_ENTRY_IS_SUB_MAP)) 1279 continue; 1280 1281 if ((object = entry->object.vm_object) == NULL) 1282 continue; 1283 1284 /* Ignore memory-mapped devices and such things. */ 1285 VM_OBJECT_LOCK(object); 1286 while ((backing_object = object->backing_object) != NULL) { 1287 VM_OBJECT_LOCK(backing_object); 1288 VM_OBJECT_UNLOCK(object); 1289 object = backing_object; 1290 } 1291 ignore_entry = object->type != OBJT_DEFAULT && 1292 object->type != OBJT_SWAP && object->type != OBJT_VNODE; 1293 VM_OBJECT_UNLOCK(object); 1294 if (ignore_entry) 1295 continue; 1296 1297 (*func)(entry, closure); 1298 } 1299 vm_map_unlock_read(map); 1300 } 1301 1302 /* 1303 * Write the core file header to the file, including padding up to 1304 * the page boundary. 1305 */ 1306 static int 1307 __elfN(corehdr)(td, vp, cred, numsegs, hdr, hdrsize, gzfile) 1308 struct thread *td; 1309 struct vnode *vp; 1310 struct ucred *cred; 1311 int numsegs; 1312 size_t hdrsize; 1313 void *hdr; 1314 gzFile gzfile; 1315 { 1316 size_t off; 1317 1318 /* Fill in the header. */ 1319 bzero(hdr, hdrsize); 1320 off = 0; 1321 __elfN(puthdr)(td, hdr, &off, numsegs); 1322 1323 if (!gzfile) { 1324 /* Write it to the core file. */ 1325 return (vn_rdwr_inchunks(UIO_WRITE, vp, hdr, hdrsize, (off_t)0, 1326 UIO_SYSSPACE, IO_UNIT | IO_DIRECT, cred, NOCRED, NULL, 1327 td)); 1328 } else { 1329 #ifdef COMPRESS_USER_CORES 1330 if (gzwrite(gzfile, hdr, hdrsize) != hdrsize) { 1331 log(LOG_WARNING, 1332 "Failed to compress core file header for process" 1333 " %s.\n", curproc->p_comm); 1334 return (EFAULT); 1335 } 1336 else { 1337 return (0); 1338 } 1339 #else 1340 panic("shouldn't be here"); 1341 #endif 1342 } 1343 } 1344 1345 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32 1346 #include <compat/freebsd32/freebsd32.h> 1347 1348 typedef struct prstatus32 elf_prstatus_t; 1349 typedef struct prpsinfo32 elf_prpsinfo_t; 1350 typedef struct fpreg32 elf_prfpregset_t; 1351 typedef struct fpreg32 elf_fpregset_t; 1352 typedef struct reg32 elf_gregset_t; 1353 typedef struct thrmisc32 elf_thrmisc_t; 1354 #else 1355 typedef prstatus_t elf_prstatus_t; 1356 typedef prpsinfo_t elf_prpsinfo_t; 1357 typedef prfpregset_t elf_prfpregset_t; 1358 typedef prfpregset_t elf_fpregset_t; 1359 typedef gregset_t elf_gregset_t; 1360 typedef thrmisc_t elf_thrmisc_t; 1361 #endif 1362 1363 static void 1364 __elfN(puthdr)(struct thread *td, void *dst, size_t *off, int numsegs) 1365 { 1366 struct { 1367 elf_prstatus_t status; 1368 elf_prfpregset_t fpregset; 1369 elf_prpsinfo_t psinfo; 1370 elf_thrmisc_t thrmisc; 1371 } *tempdata; 1372 elf_prstatus_t *status; 1373 elf_prfpregset_t *fpregset; 1374 elf_prpsinfo_t *psinfo; 1375 elf_thrmisc_t *thrmisc; 1376 struct proc *p; 1377 struct thread *thr; 1378 size_t ehoff, noteoff, notesz, phoff; 1379 1380 p = td->td_proc; 1381 1382 ehoff = *off; 1383 *off += sizeof(Elf_Ehdr); 1384 1385 phoff = *off; 1386 *off += (numsegs + 1) * sizeof(Elf_Phdr); 1387 1388 noteoff = *off; 1389 /* 1390 * Don't allocate space for the notes if we're just calculating 1391 * the size of the header. We also don't collect the data. 1392 */ 1393 if (dst != NULL) { 1394 tempdata = malloc(sizeof(*tempdata), M_TEMP, M_ZERO|M_WAITOK); 1395 status = &tempdata->status; 1396 fpregset = &tempdata->fpregset; 1397 psinfo = &tempdata->psinfo; 1398 thrmisc = &tempdata->thrmisc; 1399 } else { 1400 tempdata = NULL; 1401 status = NULL; 1402 fpregset = NULL; 1403 psinfo = NULL; 1404 thrmisc = NULL; 1405 } 1406 1407 if (dst != NULL) { 1408 psinfo->pr_version = PRPSINFO_VERSION; 1409 psinfo->pr_psinfosz = sizeof(elf_prpsinfo_t); 1410 strlcpy(psinfo->pr_fname, p->p_comm, sizeof(psinfo->pr_fname)); 1411 /* 1412 * XXX - We don't fill in the command line arguments properly 1413 * yet. 1414 */ 1415 strlcpy(psinfo->pr_psargs, p->p_comm, 1416 sizeof(psinfo->pr_psargs)); 1417 } 1418 __elfN(putnote)(dst, off, "FreeBSD", NT_PRPSINFO, psinfo, 1419 sizeof *psinfo); 1420 1421 /* 1422 * To have the debugger select the right thread (LWP) as the initial 1423 * thread, we dump the state of the thread passed to us in td first. 1424 * This is the thread that causes the core dump and thus likely to 1425 * be the right thread one wants to have selected in the debugger. 1426 */ 1427 thr = td; 1428 while (thr != NULL) { 1429 if (dst != NULL) { 1430 status->pr_version = PRSTATUS_VERSION; 1431 status->pr_statussz = sizeof(elf_prstatus_t); 1432 status->pr_gregsetsz = sizeof(elf_gregset_t); 1433 status->pr_fpregsetsz = sizeof(elf_fpregset_t); 1434 status->pr_osreldate = osreldate; 1435 status->pr_cursig = p->p_sig; 1436 status->pr_pid = thr->td_tid; 1437 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32 1438 fill_regs32(thr, &status->pr_reg); 1439 fill_fpregs32(thr, fpregset); 1440 #else 1441 fill_regs(thr, &status->pr_reg); 1442 fill_fpregs(thr, fpregset); 1443 #endif 1444 memset(&thrmisc->_pad, 0, sizeof (thrmisc->_pad)); 1445 strcpy(thrmisc->pr_tname, thr->td_name); 1446 } 1447 __elfN(putnote)(dst, off, "FreeBSD", NT_PRSTATUS, status, 1448 sizeof *status); 1449 __elfN(putnote)(dst, off, "FreeBSD", NT_FPREGSET, fpregset, 1450 sizeof *fpregset); 1451 __elfN(putnote)(dst, off, "FreeBSD", NT_THRMISC, thrmisc, 1452 sizeof *thrmisc); 1453 /* 1454 * Allow for MD specific notes, as well as any MD 1455 * specific preparations for writing MI notes. 1456 */ 1457 __elfN(dump_thread)(thr, dst, off); 1458 1459 thr = (thr == td) ? TAILQ_FIRST(&p->p_threads) : 1460 TAILQ_NEXT(thr, td_plist); 1461 if (thr == td) 1462 thr = TAILQ_NEXT(thr, td_plist); 1463 } 1464 1465 notesz = *off - noteoff; 1466 1467 if (dst != NULL) 1468 free(tempdata, M_TEMP); 1469 1470 /* Align up to a page boundary for the program segments. */ 1471 *off = round_page(*off); 1472 1473 if (dst != NULL) { 1474 Elf_Ehdr *ehdr; 1475 Elf_Phdr *phdr; 1476 struct phdr_closure phc; 1477 1478 /* 1479 * Fill in the ELF header. 1480 */ 1481 ehdr = (Elf_Ehdr *)((char *)dst + ehoff); 1482 ehdr->e_ident[EI_MAG0] = ELFMAG0; 1483 ehdr->e_ident[EI_MAG1] = ELFMAG1; 1484 ehdr->e_ident[EI_MAG2] = ELFMAG2; 1485 ehdr->e_ident[EI_MAG3] = ELFMAG3; 1486 ehdr->e_ident[EI_CLASS] = ELF_CLASS; 1487 ehdr->e_ident[EI_DATA] = ELF_DATA; 1488 ehdr->e_ident[EI_VERSION] = EV_CURRENT; 1489 ehdr->e_ident[EI_OSABI] = ELFOSABI_FREEBSD; 1490 ehdr->e_ident[EI_ABIVERSION] = 0; 1491 ehdr->e_ident[EI_PAD] = 0; 1492 ehdr->e_type = ET_CORE; 1493 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32 1494 ehdr->e_machine = ELF_ARCH32; 1495 #else 1496 ehdr->e_machine = ELF_ARCH; 1497 #endif 1498 ehdr->e_version = EV_CURRENT; 1499 ehdr->e_entry = 0; 1500 ehdr->e_phoff = phoff; 1501 ehdr->e_flags = 0; 1502 ehdr->e_ehsize = sizeof(Elf_Ehdr); 1503 ehdr->e_phentsize = sizeof(Elf_Phdr); 1504 ehdr->e_phnum = numsegs + 1; 1505 ehdr->e_shentsize = sizeof(Elf_Shdr); 1506 ehdr->e_shnum = 0; 1507 ehdr->e_shstrndx = SHN_UNDEF; 1508 1509 /* 1510 * Fill in the program header entries. 1511 */ 1512 phdr = (Elf_Phdr *)((char *)dst + phoff); 1513 1514 /* The note segement. */ 1515 phdr->p_type = PT_NOTE; 1516 phdr->p_offset = noteoff; 1517 phdr->p_vaddr = 0; 1518 phdr->p_paddr = 0; 1519 phdr->p_filesz = notesz; 1520 phdr->p_memsz = 0; 1521 phdr->p_flags = 0; 1522 phdr->p_align = 0; 1523 phdr++; 1524 1525 /* All the writable segments from the program. */ 1526 phc.phdr = phdr; 1527 phc.offset = *off; 1528 each_writable_segment(td, cb_put_phdr, &phc); 1529 } 1530 } 1531 1532 static void 1533 __elfN(putnote)(void *dst, size_t *off, const char *name, int type, 1534 const void *desc, size_t descsz) 1535 { 1536 Elf_Note note; 1537 1538 note.n_namesz = strlen(name) + 1; 1539 note.n_descsz = descsz; 1540 note.n_type = type; 1541 if (dst != NULL) 1542 bcopy(¬e, (char *)dst + *off, sizeof note); 1543 *off += sizeof note; 1544 if (dst != NULL) 1545 bcopy(name, (char *)dst + *off, note.n_namesz); 1546 *off += roundup2(note.n_namesz, sizeof(Elf_Size)); 1547 if (dst != NULL) 1548 bcopy(desc, (char *)dst + *off, note.n_descsz); 1549 *off += roundup2(note.n_descsz, sizeof(Elf_Size)); 1550 } 1551 1552 /* 1553 * Try to find the appropriate ABI-note section for checknote, 1554 * fetch the osreldate for binary from the ELF OSABI-note. Only the 1555 * first page of the image is searched, the same as for headers. 1556 */ 1557 static boolean_t 1558 __elfN(check_note)(struct image_params *imgp, Elf_Brandnote *checknote, 1559 int32_t *osrel) 1560 { 1561 const Elf_Note *note, *note0, *note_end; 1562 const Elf_Phdr *phdr, *pnote; 1563 const Elf_Ehdr *hdr; 1564 const char *note_name; 1565 int i; 1566 1567 pnote = NULL; 1568 hdr = (const Elf_Ehdr *)imgp->image_header; 1569 phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff); 1570 1571 for (i = 0; i < hdr->e_phnum; i++) { 1572 if (phdr[i].p_type == PT_NOTE) { 1573 pnote = &phdr[i]; 1574 break; 1575 } 1576 } 1577 1578 if (pnote == NULL || pnote->p_offset >= PAGE_SIZE || 1579 pnote->p_offset + pnote->p_filesz >= PAGE_SIZE) 1580 return (FALSE); 1581 1582 note = note0 = (const Elf_Note *)(imgp->image_header + pnote->p_offset); 1583 note_end = (const Elf_Note *)(imgp->image_header + 1584 pnote->p_offset + pnote->p_filesz); 1585 for (i = 0; i < 100 && note >= note0 && note < note_end; i++) { 1586 if (!aligned(note, Elf32_Addr)) 1587 return (FALSE); 1588 if (note->n_namesz != checknote->hdr.n_namesz || 1589 note->n_descsz != checknote->hdr.n_descsz || 1590 note->n_type != checknote->hdr.n_type) 1591 goto nextnote; 1592 note_name = (const char *)(note + 1); 1593 if (strncmp(checknote->vendor, note_name, 1594 checknote->hdr.n_namesz) != 0) 1595 goto nextnote; 1596 1597 /* 1598 * Fetch the osreldate for binary 1599 * from the ELF OSABI-note if necessary. 1600 */ 1601 if ((checknote->flags & BN_TRANSLATE_OSREL) != 0 && 1602 checknote->trans_osrel != NULL) 1603 return (checknote->trans_osrel(note, osrel)); 1604 return (TRUE); 1605 1606 nextnote: 1607 note = (const Elf_Note *)((const char *)(note + 1) + 1608 roundup2(note->n_namesz, sizeof(Elf32_Addr)) + 1609 roundup2(note->n_descsz, sizeof(Elf32_Addr))); 1610 } 1611 1612 return (FALSE); 1613 } 1614 1615 /* 1616 * Tell kern_execve.c about it, with a little help from the linker. 1617 */ 1618 static struct execsw __elfN(execsw) = { 1619 __CONCAT(exec_, __elfN(imgact)), 1620 __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) 1621 }; 1622 EXEC_SET(__CONCAT(elf, __ELF_WORD_SIZE), __elfN(execsw)); 1623 1624 #ifdef COMPRESS_USER_CORES 1625 /* 1626 * Compress and write out a core segment for a user process. 1627 * 1628 * 'inbuf' is the starting address of a VM segment in the process' address 1629 * space that is to be compressed and written out to the core file. 'dest_buf' 1630 * is a buffer in the kernel's address space. The segment is copied from 1631 * 'inbuf' to 'dest_buf' first before being processed by the compression 1632 * routine gzwrite(). This copying is necessary because the content of the VM 1633 * segment may change between the compression pass and the crc-computation pass 1634 * in gzwrite(). This is because realtime threads may preempt the UNIX kernel. 1635 */ 1636 static int 1637 compress_core (gzFile file, char *inbuf, char *dest_buf, unsigned int len, 1638 struct thread *td) 1639 { 1640 int len_compressed; 1641 int error = 0; 1642 unsigned int chunk_len; 1643 1644 while (len) { 1645 chunk_len = (len > CORE_BUF_SIZE) ? CORE_BUF_SIZE : len; 1646 copyin(inbuf, dest_buf, chunk_len); 1647 len_compressed = gzwrite(file, dest_buf, chunk_len); 1648 1649 EVENTHANDLER_INVOKE(app_coredump_progress, td, len_compressed); 1650 1651 if ((unsigned int)len_compressed != chunk_len) { 1652 log(LOG_WARNING, 1653 "compress_core: length mismatch (0x%x returned, " 1654 "0x%x expected)\n", len_compressed, chunk_len); 1655 EVENTHANDLER_INVOKE(app_coredump_error, td, 1656 "compress_core: length mismatch %x -> %x", 1657 chunk_len, len_compressed); 1658 error = EFAULT; 1659 break; 1660 } 1661 inbuf += chunk_len; 1662 len -= chunk_len; 1663 maybe_yield(); 1664 } 1665 1666 return (error); 1667 } 1668 #endif /* COMPRESS_USER_CORES */ 1669 1670 static vm_prot_t 1671 __elfN(trans_prot)(Elf_Word flags) 1672 { 1673 vm_prot_t prot; 1674 1675 prot = 0; 1676 if (flags & PF_X) 1677 prot |= VM_PROT_EXECUTE; 1678 if (flags & PF_W) 1679 prot |= VM_PROT_WRITE; 1680 if (flags & PF_R) 1681 prot |= VM_PROT_READ; 1682 #if __ELF_WORD_SIZE == 32 1683 #if defined(__amd64__) || defined(__ia64__) 1684 if (i386_read_exec && (flags & PF_R)) 1685 prot |= VM_PROT_EXECUTE; 1686 #endif 1687 #endif 1688 return (prot); 1689 } 1690 1691 static Elf_Word 1692 __elfN(untrans_prot)(vm_prot_t prot) 1693 { 1694 Elf_Word flags; 1695 1696 flags = 0; 1697 if (prot & VM_PROT_EXECUTE) 1698 flags |= PF_X; 1699 if (prot & VM_PROT_READ) 1700 flags |= PF_R; 1701 if (prot & VM_PROT_WRITE) 1702 flags |= PF_W; 1703 return (flags); 1704 } 1705