1 /*- 2 * Copyright (c) 1995-1996 Søren Schmidt 3 * Copyright (c) 1996 Peter Wemm 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer 11 * in this position and unchanged. 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. The name of the author may not be used to endorse or promote products 16 * derived from this software without specific prior written permission 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 * 29 * $FreeBSD: src/sys/kern/imgact_elf.c,v 1.73.2.13 2002/12/28 19:49:41 dillon Exp $ 30 * $DragonFly: src/sys/kern/imgact_elf.c,v 1.55 2008/08/17 17:21:36 nth Exp $ 31 */ 32 33 #include <sys/param.h> 34 #include <sys/exec.h> 35 #include <sys/fcntl.h> 36 #include <sys/file.h> 37 #include <sys/imgact.h> 38 #include <sys/imgact_elf.h> 39 #include <sys/kernel.h> 40 #include <sys/malloc.h> 41 #include <sys/mman.h> 42 #include <sys/systm.h> 43 #include <sys/proc.h> 44 #include <sys/nlookup.h> 45 #include <sys/pioctl.h> 46 #include <sys/procfs.h> 47 #include <sys/resourcevar.h> 48 #include <sys/signalvar.h> 49 #include <sys/stat.h> 50 #include <sys/syscall.h> 51 #include <sys/sysctl.h> 52 #include <sys/sysent.h> 53 #include <sys/vnode.h> 54 #include <sys/eventhandler.h> 55 56 #include <cpu/lwbuf.h> 57 58 #include <vm/vm.h> 59 #include <vm/vm_kern.h> 60 #include <vm/vm_param.h> 61 #include <vm/pmap.h> 62 #include <sys/lock.h> 63 #include <vm/vm_map.h> 64 #include <vm/vm_object.h> 65 #include <vm/vm_extern.h> 66 67 #include <machine/elf.h> 68 #include <machine/md_var.h> 69 #include <sys/mount.h> 70 #include <sys/ckpt.h> 71 #define OLD_EI_BRAND 8 72 73 __ElfType(Brandinfo); 74 __ElfType(Auxargs); 75 76 static int elf_check_header (const Elf_Ehdr *hdr); 77 static int elf_freebsd_fixup (register_t **stack_base, 78 struct image_params *imgp); 79 static int elf_load_file (struct proc *p, const char *file, u_long *addr, 80 u_long *entry); 81 static int elf_load_section (struct proc *p, 82 struct vmspace *vmspace, struct vnode *vp, 83 vm_offset_t offset, caddr_t vmaddr, size_t memsz, size_t filsz, 84 vm_prot_t prot); 85 static int exec_elf_imgact (struct image_params *imgp); 86 87 static int elf_trace = 0; 88 SYSCTL_INT(_debug, OID_AUTO, elf_trace, CTLFLAG_RW, &elf_trace, 0, ""); 89 static int elf_legacy_coredump = 0; 90 SYSCTL_INT(_debug, OID_AUTO, elf_legacy_coredump, CTLFLAG_RW, 91 &elf_legacy_coredump, 0, 92 "Do not dump inaccessible mappings, legacy coredump mode"); 93 94 static int dragonfly_match_abi_note(const Elf_Note *); 95 static int freebsd_match_abi_note(const Elf_Note *); 96 97 static struct sysentvec elf_freebsd_sysvec = { 98 SYS_MAXSYSCALL, 99 sysent, 100 -1, 101 0, 102 0, 103 0, 104 0, 105 0, 106 elf_freebsd_fixup, 107 sendsig, 108 sigcode, 109 &szsigcode, 110 0, 111 #if defined(__x86_64__) 112 "FreeBSD ELF64", 113 #else 114 "FreeBSD ELF32", 115 #endif 116 elf_coredump, 117 NULL, 118 MINSIGSTKSZ 119 }; 120 121 static Elf_Brandinfo freebsd_brand_info = { 122 ELFOSABI_FREEBSD, 123 "FreeBSD", 124 freebsd_match_abi_note, 125 "", 126 "/usr/libexec/ld-elf.so.1", 127 &elf_freebsd_sysvec 128 }; 129 130 static Elf_Brandinfo dragonfly_brand_info = { 131 ELFOSABI_NONE, 132 "DragonFly", 133 dragonfly_match_abi_note, 134 "", 135 "/usr/libexec/ld-elf.so.2", 136 &elf_freebsd_sysvec 137 }; 138 139 static Elf_Brandinfo *elf_brand_list[MAX_BRANDS] = { 140 &dragonfly_brand_info, 141 &freebsd_brand_info, 142 NULL, NULL, NULL, 143 NULL, NULL, NULL 144 }; 145 146 static int 147 freebsd_match_abi_note(const Elf_Note *abi_note) 148 { 149 const char *abi_name = (const char *) 150 ((const uint8_t *)abi_note + sizeof(*abi_note)); 151 152 if (abi_note->n_namesz != sizeof("FreeBSD")) 153 return(FALSE); 154 if (memcmp(abi_name, "FreeBSD", sizeof("FreeBSD"))) 155 return(FALSE); 156 return(TRUE); 157 } 158 159 static int 160 dragonfly_match_abi_note(const Elf_Note *abi_note) 161 { 162 const char *abi_name = (const char *) 163 ((const uint8_t *)abi_note + sizeof(*abi_note)); 164 165 if (abi_note->n_namesz != sizeof("DragonFly")) 166 return(FALSE); 167 if (memcmp(abi_name, "DragonFly", sizeof("DragonFly"))) 168 return(FALSE); 169 return(TRUE); 170 } 171 172 int 173 elf_insert_brand_entry(Elf_Brandinfo *entry) 174 { 175 int i; 176 177 for (i=1; i<MAX_BRANDS; i++) { 178 if (elf_brand_list[i] == NULL) { 179 elf_brand_list[i] = entry; 180 break; 181 } 182 } 183 if (i == MAX_BRANDS) 184 return -1; 185 return 0; 186 } 187 188 int 189 elf_remove_brand_entry(Elf_Brandinfo *entry) 190 { 191 int i; 192 193 for (i=1; i<MAX_BRANDS; i++) { 194 if (elf_brand_list[i] == entry) { 195 elf_brand_list[i] = NULL; 196 break; 197 } 198 } 199 if (i == MAX_BRANDS) 200 return -1; 201 return 0; 202 } 203 204 /* 205 * Check if an elf brand is being used anywhere in the system. 206 * 207 * Used by the linux emulation module unloader. This isn't safe from 208 * races. 209 */ 210 struct elf_brand_inuse_info { 211 int rval; 212 Elf_Brandinfo *entry; 213 }; 214 215 static int elf_brand_inuse_callback(struct proc *p, void *data); 216 217 int 218 elf_brand_inuse(Elf_Brandinfo *entry) 219 { 220 struct elf_brand_inuse_info info; 221 222 info.rval = FALSE; 223 info.entry = entry; 224 allproc_scan(elf_brand_inuse_callback, entry); 225 return (info.rval); 226 } 227 228 static 229 int 230 elf_brand_inuse_callback(struct proc *p, void *data) 231 { 232 struct elf_brand_inuse_info *info = data; 233 234 if (p->p_sysent == info->entry->sysvec) { 235 info->rval = TRUE; 236 return(-1); 237 } 238 return(0); 239 } 240 241 static int 242 elf_check_header(const Elf_Ehdr *hdr) 243 { 244 if (!IS_ELF(*hdr) || 245 hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS || 246 hdr->e_ident[EI_DATA] != ELF_TARG_DATA || 247 hdr->e_ident[EI_VERSION] != EV_CURRENT || 248 hdr->e_phentsize != sizeof(Elf_Phdr) || 249 hdr->e_ehsize != sizeof(Elf_Ehdr) || 250 hdr->e_version != ELF_TARG_VER) 251 return ENOEXEC; 252 253 if (!ELF_MACHINE_OK(hdr->e_machine)) 254 return ENOEXEC; 255 256 return 0; 257 } 258 259 static Elf_Brandinfo * 260 elf_check_abi_note(struct image_params *imgp, const Elf_Phdr *ph) 261 { 262 Elf_Brandinfo *match = NULL; 263 const Elf_Note *tmp_note; 264 struct lwbuf *lwb; 265 struct lwbuf lwb_cache; 266 const char *page; 267 char *data = NULL; 268 Elf_Off off; 269 size_t firstoff; 270 size_t len; 271 size_t firstlen; 272 273 len = ph->p_filesz; 274 off = ph->p_offset; 275 276 firstoff = off & PAGE_MASK; 277 firstlen = PAGE_SIZE - firstoff; 278 279 if (len < sizeof(Elf_Note) || len > PAGE_SIZE) 280 return NULL; /* ENOEXEC? */ 281 282 lwb = &lwb_cache; 283 if (exec_map_page(imgp, off >> PAGE_SHIFT, &lwb, &page)) 284 return NULL; 285 286 /* 287 * Crosses page boundary? Is that allowed? 288 */ 289 if (firstlen < len) { 290 data = kmalloc(len, M_TEMP, M_WAITOK); 291 292 bcopy(page + firstoff, data, firstlen); 293 294 exec_unmap_page(lwb); 295 lwb = &lwb_cache; 296 if (exec_map_page(imgp, (off >> PAGE_SHIFT) + 1, &lwb, &page)) { 297 kfree(data, M_TEMP); 298 return NULL; 299 } 300 bcopy(page, data + firstlen, len - firstlen); 301 tmp_note = (void *)data; 302 } else { 303 tmp_note = (const void *)(page + firstoff); 304 } 305 306 while (len >= sizeof(Elf_Note)) { 307 int i; 308 size_t nlen = roundup(tmp_note->n_namesz, sizeof(Elf_Word)) + 309 roundup(tmp_note->n_descsz, sizeof(Elf_Word)) + 310 sizeof(Elf_Note); 311 312 if (nlen > len) 313 break; 314 315 if (tmp_note->n_type != 1) 316 goto next; 317 318 for (i = 0; i < MAX_BRANDS; i++) { 319 Elf_Brandinfo *bi = elf_brand_list[i]; 320 321 if (bi != NULL && bi->match_abi_note != NULL && 322 bi->match_abi_note(tmp_note)) { 323 match = bi; 324 break; 325 } 326 } 327 328 if (match != NULL) 329 break; 330 331 next: 332 len -= nlen; 333 tmp_note += nlen; 334 } 335 336 if (data != NULL) 337 kfree(data, M_TEMP); 338 exec_unmap_page(lwb); 339 340 return (match); 341 } 342 343 static int 344 elf_load_section(struct proc *p, struct vmspace *vmspace, struct vnode *vp, 345 vm_offset_t offset, caddr_t vmaddr, size_t memsz, 346 size_t filsz, vm_prot_t prot) 347 { 348 size_t map_len; 349 vm_offset_t map_addr; 350 int error, rv, cow; 351 int count; 352 size_t copy_len; 353 vm_object_t object; 354 vm_offset_t file_addr; 355 356 object = vp->v_object; 357 error = 0; 358 359 /* 360 * It's necessary to fail if the filsz + offset taken from the 361 * header is greater than the actual file pager object's size. 362 * If we were to allow this, then the vm_map_find() below would 363 * walk right off the end of the file object and into the ether. 364 * 365 * While I'm here, might as well check for something else that 366 * is invalid: filsz cannot be greater than memsz. 367 */ 368 if ((off_t)filsz + offset > vp->v_filesize || filsz > memsz) { 369 uprintf("elf_load_section: truncated ELF file\n"); 370 return (ENOEXEC); 371 } 372 373 map_addr = trunc_page((vm_offset_t)vmaddr); 374 file_addr = trunc_page(offset); 375 376 /* 377 * We have two choices. We can either clear the data in the last page 378 * of an oversized mapping, or we can start the anon mapping a page 379 * early and copy the initialized data into that first page. We 380 * choose the second.. 381 */ 382 if (memsz > filsz) 383 map_len = trunc_page(offset+filsz) - file_addr; 384 else 385 map_len = round_page(offset+filsz) - file_addr; 386 387 if (map_len != 0) { 388 vm_object_reference(object); 389 390 /* cow flags: don't dump readonly sections in core */ 391 cow = MAP_COPY_ON_WRITE | MAP_PREFAULT | 392 (prot & VM_PROT_WRITE ? 0 : MAP_DISABLE_COREDUMP); 393 394 count = vm_map_entry_reserve(MAP_RESERVE_COUNT); 395 vm_map_lock(&vmspace->vm_map); 396 rv = vm_map_insert(&vmspace->vm_map, &count, 397 object, 398 file_addr, /* file offset */ 399 map_addr, /* virtual start */ 400 map_addr + map_len,/* virtual end */ 401 VM_MAPTYPE_NORMAL, 402 prot, VM_PROT_ALL, 403 cow); 404 vm_map_unlock(&vmspace->vm_map); 405 vm_map_entry_release(count); 406 if (rv != KERN_SUCCESS) { 407 vm_object_deallocate(object); 408 return EINVAL; 409 } 410 411 /* we can stop now if we've covered it all */ 412 if (memsz == filsz) { 413 return 0; 414 } 415 } 416 417 418 /* 419 * We have to get the remaining bit of the file into the first part 420 * of the oversized map segment. This is normally because the .data 421 * segment in the file is extended to provide bss. It's a neat idea 422 * to try and save a page, but it's a pain in the behind to implement. 423 */ 424 copy_len = (offset + filsz) - trunc_page(offset + filsz); 425 map_addr = trunc_page((vm_offset_t)vmaddr + filsz); 426 map_len = round_page((vm_offset_t)vmaddr + memsz) - map_addr; 427 428 /* This had damn well better be true! */ 429 if (map_len != 0) { 430 count = vm_map_entry_reserve(MAP_RESERVE_COUNT); 431 vm_map_lock(&vmspace->vm_map); 432 rv = vm_map_insert(&vmspace->vm_map, &count, 433 NULL, 0, 434 map_addr, map_addr + map_len, 435 VM_MAPTYPE_NORMAL, 436 VM_PROT_ALL, VM_PROT_ALL, 437 0); 438 vm_map_unlock(&vmspace->vm_map); 439 vm_map_entry_release(count); 440 if (rv != KERN_SUCCESS) { 441 return EINVAL; 442 } 443 } 444 445 if (copy_len != 0) { 446 vm_page_t m; 447 struct lwbuf *lwb; 448 struct lwbuf lwb_cache; 449 450 m = vm_fault_object_page(object, trunc_page(offset + filsz), 451 VM_PROT_READ, 0, &error); 452 if (m) { 453 lwb = lwbuf_alloc(m, &lwb_cache); 454 error = copyout((caddr_t)lwbuf_kva(lwb), 455 (caddr_t)map_addr, copy_len); 456 lwbuf_free(lwb); 457 vm_page_unhold(m); 458 } 459 if (error) { 460 return (error); 461 } 462 } 463 464 /* 465 * set it to the specified protection 466 */ 467 vm_map_protect(&vmspace->vm_map, map_addr, map_addr + map_len, prot, 468 FALSE); 469 470 return error; 471 } 472 473 /* 474 * Load the file "file" into memory. It may be either a shared object 475 * or an executable. 476 * 477 * The "addr" reference parameter is in/out. On entry, it specifies 478 * the address where a shared object should be loaded. If the file is 479 * an executable, this value is ignored. On exit, "addr" specifies 480 * where the file was actually loaded. 481 * 482 * The "entry" reference parameter is out only. On exit, it specifies 483 * the entry point for the loaded file. 484 */ 485 static int 486 elf_load_file(struct proc *p, const char *file, u_long *addr, u_long *entry) 487 { 488 struct { 489 struct nlookupdata nd; 490 struct vattr attr; 491 struct image_params image_params; 492 } *tempdata; 493 const Elf_Ehdr *hdr = NULL; 494 const Elf_Phdr *phdr = NULL; 495 struct nlookupdata *nd; 496 struct vmspace *vmspace = p->p_vmspace; 497 struct vattr *attr; 498 struct image_params *imgp; 499 struct mount *topmnt; 500 vm_prot_t prot; 501 u_long rbase; 502 u_long base_addr = 0; 503 int error, i, numsegs; 504 505 tempdata = kmalloc(sizeof(*tempdata), M_TEMP, M_WAITOK); 506 nd = &tempdata->nd; 507 attr = &tempdata->attr; 508 imgp = &tempdata->image_params; 509 510 /* 511 * Initialize part of the common data 512 */ 513 imgp->proc = p; 514 imgp->attr = attr; 515 imgp->firstpage = NULL; 516 imgp->image_header = NULL; 517 imgp->vp = NULL; 518 519 error = nlookup_init(nd, file, UIO_SYSSPACE, NLC_FOLLOW); 520 if (error == 0) 521 error = nlookup(nd); 522 if (error == 0) 523 error = cache_vget(&nd->nl_nch, nd->nl_cred, LK_EXCLUSIVE, &imgp->vp); 524 topmnt = nd->nl_nch.mount; 525 nlookup_done(nd); 526 if (error) 527 goto fail; 528 529 /* 530 * Check permissions, modes, uid, etc on the file, and "open" it. 531 */ 532 error = exec_check_permissions(imgp, topmnt); 533 if (error) { 534 vn_unlock(imgp->vp); 535 goto fail; 536 } 537 538 error = exec_map_first_page(imgp); 539 /* 540 * Also make certain that the interpreter stays the same, so set 541 * its VTEXT flag, too. 542 */ 543 if (error == 0) 544 vsetflags(imgp->vp, VTEXT); 545 vn_unlock(imgp->vp); 546 if (error) 547 goto fail; 548 549 hdr = (const Elf_Ehdr *)imgp->image_header; 550 if ((error = elf_check_header(hdr)) != 0) 551 goto fail; 552 if (hdr->e_type == ET_DYN) 553 rbase = *addr; 554 else if (hdr->e_type == ET_EXEC) 555 rbase = 0; 556 else { 557 error = ENOEXEC; 558 goto fail; 559 } 560 561 /* Only support headers that fit within first page for now 562 * (multiplication of two Elf_Half fields will not overflow) */ 563 if ((hdr->e_phoff > PAGE_SIZE) || 564 (hdr->e_phentsize * hdr->e_phnum) > PAGE_SIZE - hdr->e_phoff) { 565 error = ENOEXEC; 566 goto fail; 567 } 568 569 phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff); 570 571 for (i = 0, numsegs = 0; i < hdr->e_phnum; i++) { 572 if (phdr[i].p_type == PT_LOAD) { /* Loadable segment */ 573 prot = 0; 574 if (phdr[i].p_flags & PF_X) 575 prot |= VM_PROT_EXECUTE; 576 if (phdr[i].p_flags & PF_W) 577 prot |= VM_PROT_WRITE; 578 if (phdr[i].p_flags & PF_R) 579 prot |= VM_PROT_READ; 580 581 error = elf_load_section( 582 p, vmspace, imgp->vp, 583 phdr[i].p_offset, 584 (caddr_t)phdr[i].p_vaddr + 585 rbase, 586 phdr[i].p_memsz, 587 phdr[i].p_filesz, prot); 588 if (error != 0) 589 goto fail; 590 /* 591 * Establish the base address if this is the 592 * first segment. 593 */ 594 if (numsegs == 0) 595 base_addr = trunc_page(phdr[i].p_vaddr + rbase); 596 numsegs++; 597 } 598 } 599 *addr = base_addr; 600 *entry=(unsigned long)hdr->e_entry + rbase; 601 602 fail: 603 if (imgp->firstpage) 604 exec_unmap_first_page(imgp); 605 if (imgp->vp) { 606 vrele(imgp->vp); 607 imgp->vp = NULL; 608 } 609 kfree(tempdata, M_TEMP); 610 611 return error; 612 } 613 614 /* 615 * non static, as it can be overridden by start_init() 616 */ 617 int fallback_elf_brand = -1; 618 SYSCTL_INT(_kern, OID_AUTO, fallback_elf_brand, CTLFLAG_RW, 619 &fallback_elf_brand, -1, 620 "ELF brand of last resort"); 621 622 static int can_exec_dyn = 1; 623 SYSCTL_INT(_kern, OID_AUTO, elf_exec_dyn, CTLFLAG_RW, 624 &can_exec_dyn, 1, 625 "ELF: can exec shared libraries"); 626 627 static int 628 exec_elf_imgact(struct image_params *imgp) 629 { 630 const Elf_Ehdr *hdr = (const Elf_Ehdr *) imgp->image_header; 631 const Elf_Phdr *phdr; 632 Elf_Auxargs *elf_auxargs = NULL; 633 struct vmspace *vmspace; 634 vm_prot_t prot; 635 u_long text_size = 0, data_size = 0, total_size = 0; 636 u_long text_addr = 0, data_addr = 0; 637 u_long seg_size, seg_addr; 638 u_long addr, entry = 0, proghdr = 0; 639 int error, i; 640 const char *interp = NULL; 641 const Elf_Note *abi_note = NULL; 642 Elf_Brandinfo *brand_info = NULL; 643 char *path; 644 645 error = 0; 646 647 /* 648 * Do we have a valid ELF header ? 649 * We allow execution of ET_EXEC and, if kern.elf_exec_dyn is 1, ET_DYN. 650 */ 651 if (elf_check_header(hdr) != 0 || 652 (hdr->e_type != ET_EXEC && (!can_exec_dyn || hdr->e_type != ET_DYN))) 653 return -1; 654 655 /* 656 * From here on down, we return an errno, not -1, as we've 657 * detected an ELF file. 658 */ 659 660 if ((hdr->e_phoff > PAGE_SIZE) || 661 (hdr->e_phoff + hdr->e_phentsize * hdr->e_phnum) > PAGE_SIZE) { 662 /* Only support headers in first page for now */ 663 return ENOEXEC; 664 } 665 phdr = (const Elf_Phdr*)(imgp->image_header + hdr->e_phoff); 666 667 /* 668 * From this point on, we may have resources that need to be freed. 669 */ 670 671 exec_new_vmspace(imgp, NULL); 672 673 /* 674 * Yeah, I'm paranoid. There is every reason in the world to get 675 * VTEXT now since from here on out, there are places we can have 676 * a context switch. Better safe than sorry; I really don't want 677 * the file to change while it's being loaded. 678 */ 679 vsetflags(imgp->vp, VTEXT); 680 681 vmspace = imgp->proc->p_vmspace; 682 683 for (i = 0; i < hdr->e_phnum; i++) { 684 switch(phdr[i].p_type) { 685 686 case PT_LOAD: /* Loadable segment */ 687 prot = 0; 688 if (phdr[i].p_flags & PF_X) 689 prot |= VM_PROT_EXECUTE; 690 if (phdr[i].p_flags & PF_W) 691 prot |= VM_PROT_WRITE; 692 if (phdr[i].p_flags & PF_R) 693 prot |= VM_PROT_READ; 694 695 if ((error = elf_load_section(imgp->proc, 696 vmspace, imgp->vp, 697 phdr[i].p_offset, 698 (caddr_t)phdr[i].p_vaddr, 699 phdr[i].p_memsz, 700 phdr[i].p_filesz, prot)) != 0) 701 goto fail; 702 703 /* 704 * If this segment contains the program headers, 705 * remember their virtual address for the AT_PHDR 706 * aux entry. Static binaries don't usually include 707 * a PT_PHDR entry. 708 */ 709 if (phdr[i].p_offset == 0 && 710 hdr->e_phoff + hdr->e_phnum * hdr->e_phentsize 711 <= phdr[i].p_filesz) 712 proghdr = phdr[i].p_vaddr + hdr->e_phoff; 713 714 seg_addr = trunc_page(phdr[i].p_vaddr); 715 seg_size = round_page(phdr[i].p_memsz + 716 phdr[i].p_vaddr - seg_addr); 717 718 /* 719 * Is this .text or .data? We can't use 720 * VM_PROT_WRITE or VM_PROT_EXEC, it breaks the 721 * alpha terribly and possibly does other bad 722 * things so we stick to the old way of figuring 723 * it out: If the segment contains the program 724 * entry point, it's a text segment, otherwise it 725 * is a data segment. 726 * 727 * Note that obreak() assumes that data_addr + 728 * data_size == end of data load area, and the ELF 729 * file format expects segments to be sorted by 730 * address. If multiple data segments exist, the 731 * last one will be used. 732 */ 733 if (hdr->e_entry >= phdr[i].p_vaddr && 734 hdr->e_entry < (phdr[i].p_vaddr + 735 phdr[i].p_memsz)) { 736 text_size = seg_size; 737 text_addr = seg_addr; 738 entry = (u_long)hdr->e_entry; 739 } else { 740 data_size = seg_size; 741 data_addr = seg_addr; 742 } 743 total_size += seg_size; 744 745 /* 746 * Check limits. It should be safe to check the 747 * limits after loading the segment since we do 748 * not actually fault in all the segment's pages. 749 */ 750 if (data_size > 751 imgp->proc->p_rlimit[RLIMIT_DATA].rlim_cur || 752 text_size > maxtsiz || 753 total_size > 754 imgp->proc->p_rlimit[RLIMIT_VMEM].rlim_cur) { 755 error = ENOMEM; 756 goto fail; 757 } 758 break; 759 case PT_INTERP: /* Path to interpreter */ 760 if (phdr[i].p_filesz > MAXPATHLEN || 761 phdr[i].p_offset + phdr[i].p_filesz > PAGE_SIZE) { 762 error = ENOEXEC; 763 goto fail; 764 } 765 interp = imgp->image_header + phdr[i].p_offset; 766 break; 767 case PT_NOTE: /* Check for .note.ABI-tag */ 768 if (brand_info == NULL) 769 brand_info = elf_check_abi_note(imgp, &phdr[i]); 770 break; 771 case PT_PHDR: /* Program header table info */ 772 proghdr = phdr[i].p_vaddr; 773 break; 774 default: 775 break; 776 } 777 } 778 779 vmspace->vm_tsize = text_size >> PAGE_SHIFT; 780 vmspace->vm_taddr = (caddr_t)(uintptr_t)text_addr; 781 vmspace->vm_dsize = data_size >> PAGE_SHIFT; 782 vmspace->vm_daddr = (caddr_t)(uintptr_t)data_addr; 783 784 addr = ELF_RTLD_ADDR(vmspace); 785 786 imgp->entry_addr = entry; 787 788 /* We support three types of branding -- (1) the ELF EI_OSABI field 789 * that SCO added to the ELF spec, (2) FreeBSD 3.x's traditional string 790 * branding w/in the ELF header, and (3) path of the `interp_path' 791 * field. We should also look for an ".note.ABI-tag" ELF section now 792 * in all Linux ELF binaries, FreeBSD 4.1+, and some NetBSD ones. 793 */ 794 795 /* If the executable has a brand, search for it in the brand list. */ 796 if (brand_info == NULL && hdr->e_ident[EI_OSABI] != ELFOSABI_NONE) { 797 for (i = 0; i < MAX_BRANDS; i++) { 798 Elf_Brandinfo *bi = elf_brand_list[i]; 799 800 if (bi != NULL && 801 (hdr->e_ident[EI_OSABI] == bi->brand 802 || 0 == 803 strncmp((const char *)&hdr->e_ident[OLD_EI_BRAND], 804 bi->compat_3_brand, strlen(bi->compat_3_brand)))) { 805 brand_info = bi; 806 break; 807 } 808 } 809 } 810 811 /* Search for a recognized ABI. */ 812 if (brand_info == NULL && abi_note != NULL) { 813 } 814 815 /* 816 * ELFOSABI_NONE == ELFOSABI_SYSV, so a SYSV binary misses all 817 * checks so far, since it is neither branded nor does it have 818 * an ABI note. If the EI_OSABI field is ELFOSABI_NONE, assume 819 * it is svr4 and look for an entry in the elf_brand_list with 820 * match_abi_note == NULL. 821 */ 822 if (brand_info == NULL && hdr->e_ident[EI_OSABI] == ELFOSABI_NONE) { 823 for (i = 0; i < MAX_BRANDS; i++) { 824 Elf_Brandinfo *bi = elf_brand_list[i]; 825 826 if (bi != NULL && bi->match_abi_note == NULL && 827 ELFOSABI_SYSV == bi->brand) { 828 brand_info = bi; 829 break; 830 } 831 } 832 } 833 834 /* Lacking a recognized ABI, search for a recognized interpreter. */ 835 if (brand_info == NULL && interp != NULL) { 836 for (i = 0; i < MAX_BRANDS; i++) { 837 Elf_Brandinfo *bi = elf_brand_list[i]; 838 839 if (bi != NULL && 840 strcmp(interp, bi->interp_path) == 0) { 841 brand_info = bi; 842 break; 843 } 844 } 845 } 846 847 /* Lacking a recognized interpreter, try the default brand */ 848 if (brand_info == NULL) { 849 for (i = 0; i < MAX_BRANDS; i++) { 850 Elf_Brandinfo *bi = elf_brand_list[i]; 851 852 if (bi != NULL && fallback_elf_brand == bi->brand) { 853 brand_info = bi; 854 break; 855 } 856 } 857 } 858 859 if (brand_info == NULL) { 860 uprintf("ELF binary type \"%u\" not known.\n", 861 hdr->e_ident[EI_OSABI]); 862 error = ENOEXEC; 863 goto fail; 864 } 865 866 imgp->proc->p_sysent = brand_info->sysvec; 867 EVENTHANDLER_INVOKE(process_exec, imgp); 868 869 if (interp != NULL) { 870 path = kmalloc(MAXPATHLEN, M_TEMP, M_WAITOK); 871 ksnprintf(path, MAXPATHLEN, "%s%s", 872 brand_info->emul_path, interp); 873 if ((error = elf_load_file(imgp->proc, path, &addr, 874 &imgp->entry_addr)) != 0) { 875 if ((error = elf_load_file(imgp->proc, interp, &addr, 876 &imgp->entry_addr)) != 0) { 877 uprintf("ELF interpreter %s not found\n", path); 878 kfree(path, M_TEMP); 879 goto fail; 880 } 881 } 882 kfree(path, M_TEMP); 883 } else { 884 addr = 0; 885 } 886 887 /* 888 * Construct auxargs table (used by the fixup routine) 889 */ 890 elf_auxargs = kmalloc(sizeof(Elf_Auxargs), M_TEMP, M_WAITOK); 891 elf_auxargs->execfd = -1; 892 elf_auxargs->phdr = proghdr; 893 elf_auxargs->phent = hdr->e_phentsize; 894 elf_auxargs->phnum = hdr->e_phnum; 895 elf_auxargs->pagesz = PAGE_SIZE; 896 elf_auxargs->base = addr; 897 elf_auxargs->flags = 0; 898 elf_auxargs->entry = entry; 899 elf_auxargs->trace = elf_trace; 900 901 imgp->auxargs = elf_auxargs; 902 imgp->interpreted = 0; 903 904 fail: 905 return error; 906 } 907 908 static int 909 elf_freebsd_fixup(register_t **stack_base, struct image_params *imgp) 910 { 911 Elf_Auxargs *args = (Elf_Auxargs *)imgp->auxargs; 912 register_t *pos; 913 914 pos = *stack_base + (imgp->args->argc + imgp->args->envc + 2); 915 916 if (args->trace) { 917 AUXARGS_ENTRY(pos, AT_DEBUG, 1); 918 } 919 if (args->execfd != -1) { 920 AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd); 921 } 922 AUXARGS_ENTRY(pos, AT_PHDR, args->phdr); 923 AUXARGS_ENTRY(pos, AT_PHENT, args->phent); 924 AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum); 925 AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz); 926 AUXARGS_ENTRY(pos, AT_FLAGS, args->flags); 927 AUXARGS_ENTRY(pos, AT_ENTRY, args->entry); 928 AUXARGS_ENTRY(pos, AT_BASE, args->base); 929 AUXARGS_ENTRY(pos, AT_NULL, 0); 930 931 kfree(imgp->auxargs, M_TEMP); 932 imgp->auxargs = NULL; 933 934 (*stack_base)--; 935 suword(*stack_base, (long) imgp->args->argc); 936 return 0; 937 } 938 939 /* 940 * Code for generating ELF core dumps. 941 */ 942 943 typedef int (*segment_callback) (vm_map_entry_t, void *); 944 945 /* Closure for cb_put_phdr(). */ 946 struct phdr_closure { 947 Elf_Phdr *phdr; /* Program header to fill in (incremented) */ 948 Elf_Phdr *phdr_max; /* Pointer bound for error check */ 949 Elf_Off offset; /* Offset of segment in core file */ 950 }; 951 952 /* Closure for cb_size_segment(). */ 953 struct sseg_closure { 954 int count; /* Count of writable segments. */ 955 size_t vsize; /* Total size of all writable segments. */ 956 }; 957 958 /* Closure for cb_put_fp(). */ 959 struct fp_closure { 960 struct vn_hdr *vnh; 961 struct vn_hdr *vnh_max; 962 int count; 963 struct stat *sb; 964 }; 965 966 typedef struct elf_buf { 967 char *buf; 968 size_t off; 969 size_t off_max; 970 } *elf_buf_t; 971 972 static void *target_reserve(elf_buf_t target, size_t bytes, int *error); 973 974 static int cb_put_phdr (vm_map_entry_t, void *); 975 static int cb_size_segment (vm_map_entry_t, void *); 976 static int cb_fpcount_segment(vm_map_entry_t, void *); 977 static int cb_put_fp(vm_map_entry_t, void *); 978 979 980 static int each_segment (struct proc *, segment_callback, void *, int); 981 static int elf_corehdr (struct lwp *, int, struct file *, struct ucred *, 982 int, elf_buf_t); 983 enum putmode { WRITE, DRYRUN }; 984 static int elf_puthdr (struct lwp *, elf_buf_t, int sig, enum putmode, 985 int, struct file *); 986 static int elf_putallnotes(struct lwp *, elf_buf_t, int, enum putmode); 987 static int elf_putnote (elf_buf_t, const char *, int, const void *, size_t); 988 989 static int elf_putsigs(struct lwp *, elf_buf_t); 990 static int elf_puttextvp(struct proc *, elf_buf_t); 991 static int elf_putfiles(struct proc *, elf_buf_t, struct file *); 992 993 extern int osreldate; 994 995 int 996 elf_coredump(struct lwp *lp, int sig, struct vnode *vp, off_t limit) 997 { 998 struct file *fp; 999 int error; 1000 1001 if ((error = falloc(NULL, &fp, NULL)) != 0) 1002 return (error); 1003 fsetcred(fp, lp->lwp_proc->p_ucred); 1004 1005 /* 1006 * XXX fixme. 1007 */ 1008 fp->f_type = DTYPE_VNODE; 1009 fp->f_flag = O_CREAT|O_WRONLY|O_NOFOLLOW; 1010 fp->f_ops = &vnode_fileops; 1011 fp->f_data = vp; 1012 vn_unlock(vp); 1013 1014 error = generic_elf_coredump(lp, sig, fp, limit); 1015 1016 fp->f_type = 0; 1017 fp->f_flag = 0; 1018 fp->f_ops = &badfileops; 1019 fp->f_data = NULL; 1020 fdrop(fp); 1021 return (error); 1022 } 1023 1024 int 1025 generic_elf_coredump(struct lwp *lp, int sig, struct file *fp, off_t limit) 1026 { 1027 struct proc *p = lp->lwp_proc; 1028 struct ucred *cred = p->p_ucred; 1029 int error = 0; 1030 struct sseg_closure seginfo; 1031 struct elf_buf target; 1032 1033 if (!fp) 1034 kprintf("can't dump core - null fp\n"); 1035 1036 /* 1037 * Size the program segments 1038 */ 1039 seginfo.count = 0; 1040 seginfo.vsize = 0; 1041 each_segment(p, cb_size_segment, &seginfo, 1); 1042 1043 /* 1044 * Calculate the size of the core file header area by making 1045 * a dry run of generating it. Nothing is written, but the 1046 * size is calculated. 1047 */ 1048 bzero(&target, sizeof(target)); 1049 elf_puthdr(lp, &target, sig, DRYRUN, seginfo.count, fp); 1050 1051 if (target.off + seginfo.vsize >= limit) 1052 return (EFAULT); 1053 1054 /* 1055 * Allocate memory for building the header, fill it up, 1056 * and write it out. 1057 */ 1058 target.off_max = target.off; 1059 target.off = 0; 1060 target.buf = kmalloc(target.off_max, M_TEMP, M_WAITOK|M_ZERO); 1061 1062 error = elf_corehdr(lp, sig, fp, cred, seginfo.count, &target); 1063 1064 /* Write the contents of all of the writable segments. */ 1065 if (error == 0) { 1066 Elf_Phdr *php; 1067 int i; 1068 ssize_t nbytes; 1069 1070 php = (Elf_Phdr *)(target.buf + sizeof(Elf_Ehdr)) + 1; 1071 for (i = 0; i < seginfo.count; i++) { 1072 error = fp_write(fp, (caddr_t)php->p_vaddr, 1073 php->p_filesz, &nbytes, UIO_USERSPACE); 1074 if (error != 0) 1075 break; 1076 php++; 1077 } 1078 } 1079 kfree(target.buf, M_TEMP); 1080 1081 return error; 1082 } 1083 1084 /* 1085 * A callback for each_segment() to write out the segment's 1086 * program header entry. 1087 */ 1088 static int 1089 cb_put_phdr(vm_map_entry_t entry, void *closure) 1090 { 1091 struct phdr_closure *phc = closure; 1092 Elf_Phdr *phdr = phc->phdr; 1093 1094 if (phc->phdr == phc->phdr_max) 1095 return EINVAL; 1096 1097 phc->offset = round_page(phc->offset); 1098 1099 phdr->p_type = PT_LOAD; 1100 phdr->p_offset = phc->offset; 1101 phdr->p_vaddr = entry->start; 1102 phdr->p_paddr = 0; 1103 phdr->p_filesz = phdr->p_memsz = entry->end - entry->start; 1104 phdr->p_align = PAGE_SIZE; 1105 phdr->p_flags = 0; 1106 if (entry->protection & VM_PROT_READ) 1107 phdr->p_flags |= PF_R; 1108 if (entry->protection & VM_PROT_WRITE) 1109 phdr->p_flags |= PF_W; 1110 if (entry->protection & VM_PROT_EXECUTE) 1111 phdr->p_flags |= PF_X; 1112 1113 phc->offset += phdr->p_filesz; 1114 ++phc->phdr; 1115 return 0; 1116 } 1117 1118 /* 1119 * A callback for each_writable_segment() to gather information about 1120 * the number of segments and their total size. 1121 */ 1122 static int 1123 cb_size_segment(vm_map_entry_t entry, void *closure) 1124 { 1125 struct sseg_closure *ssc = closure; 1126 1127 ++ssc->count; 1128 ssc->vsize += entry->end - entry->start; 1129 return 0; 1130 } 1131 1132 /* 1133 * A callback for each_segment() to gather information about 1134 * the number of text segments. 1135 */ 1136 static int 1137 cb_fpcount_segment(vm_map_entry_t entry, void *closure) 1138 { 1139 int *count = closure; 1140 struct vnode *vp; 1141 1142 if (entry->object.vm_object->type == OBJT_VNODE) { 1143 vp = (struct vnode *)entry->object.vm_object->handle; 1144 if ((vp->v_flag & VCKPT) && curproc->p_textvp == vp) 1145 return 0; 1146 ++*count; 1147 } 1148 return 0; 1149 } 1150 1151 static int 1152 cb_put_fp(vm_map_entry_t entry, void *closure) 1153 { 1154 struct fp_closure *fpc = closure; 1155 struct vn_hdr *vnh = fpc->vnh; 1156 Elf_Phdr *phdr = &vnh->vnh_phdr; 1157 struct vnode *vp; 1158 int error; 1159 1160 /* 1161 * If an entry represents a vnode then write out a file handle. 1162 * 1163 * If we are checkpointing a checkpoint-restored program we do 1164 * NOT record the filehandle for the old checkpoint vnode (which 1165 * is mapped all over the place). Instead we rely on the fact 1166 * that a checkpoint-restored program does not mmap() the checkpt 1167 * vnode NOCORE, so its contents will be written out to the 1168 * new checkpoint file. This is necessary because the 'old' 1169 * checkpoint file is typically destroyed when a new one is created 1170 * and thus cannot be used to restore the new checkpoint. 1171 * 1172 * Theoretically we could create a chain of checkpoint files and 1173 * operate the checkpointing operation kinda like an incremental 1174 * checkpoint, but a checkpoint restore would then likely wind up 1175 * referencing many prior checkpoint files and that is a bit over 1176 * the top for the purpose of the checkpoint API. 1177 */ 1178 if (entry->object.vm_object->type == OBJT_VNODE) { 1179 vp = (struct vnode *)entry->object.vm_object->handle; 1180 if ((vp->v_flag & VCKPT) && curproc->p_textvp == vp) 1181 return 0; 1182 if (vnh == fpc->vnh_max) 1183 return EINVAL; 1184 1185 if (vp->v_mount) 1186 vnh->vnh_fh.fh_fsid = vp->v_mount->mnt_stat.f_fsid; 1187 error = VFS_VPTOFH(vp, &vnh->vnh_fh.fh_fid); 1188 if (error) { 1189 char *freepath, *fullpath; 1190 1191 if (vn_fullpath(curproc, vp, &fullpath, &freepath, 0)) { 1192 kprintf("Warning: coredump, error %d: cannot store file handle for vnode %p\n", error, vp); 1193 } else { 1194 kprintf("Warning: coredump, error %d: cannot store file handle for %s\n", error, fullpath); 1195 kfree(freepath, M_TEMP); 1196 } 1197 error = 0; 1198 } 1199 1200 phdr->p_type = PT_LOAD; 1201 phdr->p_offset = 0; /* not written to core */ 1202 phdr->p_vaddr = entry->start; 1203 phdr->p_paddr = 0; 1204 phdr->p_filesz = phdr->p_memsz = entry->end - entry->start; 1205 phdr->p_align = PAGE_SIZE; 1206 phdr->p_flags = 0; 1207 if (entry->protection & VM_PROT_READ) 1208 phdr->p_flags |= PF_R; 1209 if (entry->protection & VM_PROT_WRITE) 1210 phdr->p_flags |= PF_W; 1211 if (entry->protection & VM_PROT_EXECUTE) 1212 phdr->p_flags |= PF_X; 1213 ++fpc->vnh; 1214 ++fpc->count; 1215 } 1216 return 0; 1217 } 1218 1219 /* 1220 * For each writable segment in the process's memory map, call the given 1221 * function with a pointer to the map entry and some arbitrary 1222 * caller-supplied data. 1223 */ 1224 static int 1225 each_segment(struct proc *p, segment_callback func, void *closure, int writable) 1226 { 1227 int error = 0; 1228 vm_map_t map = &p->p_vmspace->vm_map; 1229 vm_map_entry_t entry; 1230 1231 for (entry = map->header.next; error == 0 && entry != &map->header; 1232 entry = entry->next) { 1233 vm_object_t obj; 1234 1235 /* 1236 * Don't dump inaccessible mappings, deal with legacy 1237 * coredump mode. 1238 * 1239 * Note that read-only segments related to the elf binary 1240 * are marked MAP_ENTRY_NOCOREDUMP now so we no longer 1241 * need to arbitrarily ignore such segments. 1242 */ 1243 if (elf_legacy_coredump) { 1244 if (writable && (entry->protection & VM_PROT_RW) != VM_PROT_RW) 1245 continue; 1246 } else { 1247 if (writable && (entry->protection & VM_PROT_ALL) == 0) 1248 continue; 1249 } 1250 1251 /* 1252 * Dont include memory segment in the coredump if 1253 * MAP_NOCORE is set in mmap(2) or MADV_NOCORE in 1254 * madvise(2). 1255 * 1256 * Currently we only dump normal VM object maps. We do 1257 * not dump submaps or virtual page tables. 1258 */ 1259 if (writable && (entry->eflags & MAP_ENTRY_NOCOREDUMP)) 1260 continue; 1261 if (entry->maptype != VM_MAPTYPE_NORMAL) 1262 continue; 1263 if ((obj = entry->object.vm_object) == NULL) 1264 continue; 1265 1266 /* Find the deepest backing object. */ 1267 while (obj->backing_object != NULL) 1268 obj = obj->backing_object; 1269 1270 /* Ignore memory-mapped devices and such things. */ 1271 if (obj->type != OBJT_DEFAULT && 1272 obj->type != OBJT_SWAP && 1273 obj->type != OBJT_VNODE) 1274 continue; 1275 1276 error = (*func)(entry, closure); 1277 } 1278 return error; 1279 } 1280 1281 static 1282 void * 1283 target_reserve(elf_buf_t target, size_t bytes, int *error) 1284 { 1285 void *res = NULL; 1286 1287 if (target->buf) { 1288 if (target->off + bytes > target->off_max) 1289 *error = EINVAL; 1290 else 1291 res = target->buf + target->off; 1292 } 1293 target->off += bytes; 1294 return (res); 1295 } 1296 1297 /* 1298 * Write the core file header to the file, including padding up to 1299 * the page boundary. 1300 */ 1301 static int 1302 elf_corehdr(struct lwp *lp, int sig, struct file *fp, struct ucred *cred, 1303 int numsegs, elf_buf_t target) 1304 { 1305 int error; 1306 ssize_t nbytes; 1307 1308 /* 1309 * Fill in the header. The fp is passed so we can detect and flag 1310 * a checkpoint file pointer within the core file itself, because 1311 * it may not be restored from the same file handle. 1312 */ 1313 error = elf_puthdr(lp, target, sig, WRITE, numsegs, fp); 1314 1315 /* Write it to the core file. */ 1316 if (error == 0) { 1317 error = fp_write(fp, target->buf, target->off, &nbytes, 1318 UIO_SYSSPACE); 1319 } 1320 return error; 1321 } 1322 1323 static int 1324 elf_puthdr(struct lwp *lp, elf_buf_t target, int sig, enum putmode mode, 1325 int numsegs, struct file *fp) 1326 { 1327 struct proc *p = lp->lwp_proc; 1328 int error = 0; 1329 size_t phoff; 1330 size_t noteoff; 1331 size_t notesz; 1332 Elf_Ehdr *ehdr; 1333 Elf_Phdr *phdr; 1334 1335 ehdr = target_reserve(target, sizeof(Elf_Ehdr), &error); 1336 1337 phoff = target->off; 1338 phdr = target_reserve(target, (numsegs + 1) * sizeof(Elf_Phdr), &error); 1339 1340 noteoff = target->off; 1341 if (error == 0) 1342 elf_putallnotes(lp, target, sig, mode); 1343 notesz = target->off - noteoff; 1344 1345 /* 1346 * put extra cruft for dumping process state here 1347 * - we really want it be before all the program 1348 * mappings 1349 * - we just need to update the offset accordingly 1350 * and GDB will be none the wiser. 1351 */ 1352 if (error == 0) 1353 error = elf_puttextvp(p, target); 1354 if (error == 0) 1355 error = elf_putsigs(lp, target); 1356 if (error == 0) 1357 error = elf_putfiles(p, target, fp); 1358 1359 /* 1360 * Align up to a page boundary for the program segments. The 1361 * actual data will be written to the outptu file, not to elf_buf_t, 1362 * so we do not have to do any further bounds checking. 1363 */ 1364 target->off = round_page(target->off); 1365 if (error == 0 && ehdr != NULL) { 1366 /* 1367 * Fill in the ELF header. 1368 */ 1369 ehdr->e_ident[EI_MAG0] = ELFMAG0; 1370 ehdr->e_ident[EI_MAG1] = ELFMAG1; 1371 ehdr->e_ident[EI_MAG2] = ELFMAG2; 1372 ehdr->e_ident[EI_MAG3] = ELFMAG3; 1373 ehdr->e_ident[EI_CLASS] = ELF_CLASS; 1374 ehdr->e_ident[EI_DATA] = ELF_DATA; 1375 ehdr->e_ident[EI_VERSION] = EV_CURRENT; 1376 ehdr->e_ident[EI_OSABI] = ELFOSABI_NONE; 1377 ehdr->e_ident[EI_ABIVERSION] = 0; 1378 ehdr->e_ident[EI_PAD] = 0; 1379 ehdr->e_type = ET_CORE; 1380 ehdr->e_machine = ELF_ARCH; 1381 ehdr->e_version = EV_CURRENT; 1382 ehdr->e_entry = 0; 1383 ehdr->e_phoff = phoff; 1384 ehdr->e_flags = 0; 1385 ehdr->e_ehsize = sizeof(Elf_Ehdr); 1386 ehdr->e_phentsize = sizeof(Elf_Phdr); 1387 ehdr->e_phnum = numsegs + 1; 1388 ehdr->e_shentsize = sizeof(Elf_Shdr); 1389 ehdr->e_shnum = 0; 1390 ehdr->e_shstrndx = SHN_UNDEF; 1391 } 1392 if (error == 0 && phdr != NULL) { 1393 /* 1394 * Fill in the program header entries. 1395 */ 1396 struct phdr_closure phc; 1397 1398 /* The note segement. */ 1399 phdr->p_type = PT_NOTE; 1400 phdr->p_offset = noteoff; 1401 phdr->p_vaddr = 0; 1402 phdr->p_paddr = 0; 1403 phdr->p_filesz = notesz; 1404 phdr->p_memsz = 0; 1405 phdr->p_flags = 0; 1406 phdr->p_align = 0; 1407 ++phdr; 1408 1409 /* All the writable segments from the program. */ 1410 phc.phdr = phdr; 1411 phc.phdr_max = phdr + numsegs; 1412 phc.offset = target->off; 1413 each_segment(p, cb_put_phdr, &phc, 1); 1414 } 1415 return (error); 1416 } 1417 1418 /* 1419 * Append core dump notes to target ELF buffer or simply update target size 1420 * if dryrun selected. 1421 */ 1422 static int 1423 elf_putallnotes(struct lwp *corelp, elf_buf_t target, int sig, 1424 enum putmode mode) 1425 { 1426 struct proc *p = corelp->lwp_proc; 1427 int error; 1428 struct { 1429 prstatus_t status; 1430 prfpregset_t fpregs; 1431 prpsinfo_t psinfo; 1432 } *tmpdata; 1433 prstatus_t *status; 1434 prfpregset_t *fpregs; 1435 prpsinfo_t *psinfo; 1436 struct lwp *lp; 1437 1438 /* 1439 * Allocate temporary storage for notes on heap to avoid stack overflow. 1440 */ 1441 if (mode != DRYRUN) { 1442 tmpdata = kmalloc(sizeof(*tmpdata), M_TEMP, M_ZERO | M_WAITOK); 1443 status = &tmpdata->status; 1444 fpregs = &tmpdata->fpregs; 1445 psinfo = &tmpdata->psinfo; 1446 } else { 1447 tmpdata = NULL; 1448 status = NULL; 1449 fpregs = NULL; 1450 psinfo = NULL; 1451 } 1452 1453 /* 1454 * Append LWP-agnostic note. 1455 */ 1456 if (mode != DRYRUN) { 1457 psinfo->pr_version = PRPSINFO_VERSION; 1458 psinfo->pr_psinfosz = sizeof(prpsinfo_t); 1459 strncpy(psinfo->pr_fname, p->p_comm, 1460 sizeof(psinfo->pr_fname) - 1); 1461 /* 1462 * XXX - We don't fill in the command line arguments 1463 * properly yet. 1464 */ 1465 strncpy(psinfo->pr_psargs, p->p_comm, PRARGSZ); 1466 } 1467 error = 1468 elf_putnote(target, "CORE", NT_PRPSINFO, psinfo, sizeof *psinfo); 1469 if (error) 1470 goto exit; 1471 1472 /* 1473 * Append first note for LWP that triggered core so that it is 1474 * the selected one when the debugger starts. 1475 */ 1476 if (mode != DRYRUN) { 1477 status->pr_version = PRSTATUS_VERSION; 1478 status->pr_statussz = sizeof(prstatus_t); 1479 status->pr_gregsetsz = sizeof(gregset_t); 1480 status->pr_fpregsetsz = sizeof(fpregset_t); 1481 status->pr_osreldate = osreldate; 1482 status->pr_cursig = sig; 1483 /* 1484 * XXX GDB needs unique pr_pid for each LWP and does not 1485 * not support pr_pid==0 but lwp_tid can be 0, so hack unique 1486 * value. 1487 */ 1488 status->pr_pid = corelp->lwp_tid; 1489 fill_regs(corelp, &status->pr_reg); 1490 fill_fpregs(corelp, fpregs); 1491 } 1492 error = 1493 elf_putnote(target, "CORE", NT_PRSTATUS, status, sizeof *status); 1494 if (error) 1495 goto exit; 1496 error = 1497 elf_putnote(target, "CORE", NT_FPREGSET, fpregs, sizeof *fpregs); 1498 if (error) 1499 goto exit; 1500 1501 /* 1502 * Then append notes for other LWPs. 1503 */ 1504 FOREACH_LWP_IN_PROC(lp, p) { 1505 if (lp == corelp) 1506 continue; 1507 /* skip lwps being created */ 1508 if (lp->lwp_thread == NULL) 1509 continue; 1510 if (mode != DRYRUN) { 1511 status->pr_pid = lp->lwp_tid; 1512 fill_regs(lp, &status->pr_reg); 1513 fill_fpregs(lp, fpregs); 1514 } 1515 error = elf_putnote(target, "CORE", NT_PRSTATUS, 1516 status, sizeof *status); 1517 if (error) 1518 goto exit; 1519 error = elf_putnote(target, "CORE", NT_FPREGSET, 1520 fpregs, sizeof *fpregs); 1521 if (error) 1522 goto exit; 1523 } 1524 1525 exit: 1526 if (tmpdata != NULL) 1527 kfree(tmpdata, M_TEMP); 1528 return (error); 1529 } 1530 1531 /* 1532 * Generate a note sub-structure. 1533 * 1534 * NOTE: 4-byte alignment. 1535 */ 1536 static int 1537 elf_putnote(elf_buf_t target, const char *name, int type, 1538 const void *desc, size_t descsz) 1539 { 1540 int error = 0; 1541 char *dst; 1542 Elf_Note note; 1543 1544 note.n_namesz = strlen(name) + 1; 1545 note.n_descsz = descsz; 1546 note.n_type = type; 1547 dst = target_reserve(target, sizeof(note), &error); 1548 if (dst != NULL) 1549 bcopy(¬e, dst, sizeof note); 1550 dst = target_reserve(target, note.n_namesz, &error); 1551 if (dst != NULL) 1552 bcopy(name, dst, note.n_namesz); 1553 target->off = roundup2(target->off, sizeof(Elf_Word)); 1554 dst = target_reserve(target, note.n_descsz, &error); 1555 if (dst != NULL) 1556 bcopy(desc, dst, note.n_descsz); 1557 target->off = roundup2(target->off, sizeof(Elf_Word)); 1558 return(error); 1559 } 1560 1561 1562 static int 1563 elf_putsigs(struct lwp *lp, elf_buf_t target) 1564 { 1565 /* XXX lwp handle more than one lwp */ 1566 struct proc *p = lp->lwp_proc; 1567 int error = 0; 1568 struct ckpt_siginfo *csi; 1569 1570 csi = target_reserve(target, sizeof(struct ckpt_siginfo), &error); 1571 if (csi) { 1572 csi->csi_ckptpisz = sizeof(struct ckpt_siginfo); 1573 bcopy(p->p_sigacts, &csi->csi_sigacts, sizeof(*p->p_sigacts)); 1574 bcopy(&p->p_realtimer, &csi->csi_itimerval, sizeof(struct itimerval)); 1575 bcopy(&lp->lwp_sigmask, &csi->csi_sigmask, 1576 sizeof(sigset_t)); 1577 csi->csi_sigparent = p->p_sigparent; 1578 } 1579 return(error); 1580 } 1581 1582 static int 1583 elf_putfiles(struct proc *p, elf_buf_t target, struct file *ckfp) 1584 { 1585 int error = 0; 1586 int i; 1587 struct ckpt_filehdr *cfh = NULL; 1588 struct ckpt_fileinfo *cfi; 1589 struct file *fp; 1590 struct vnode *vp; 1591 /* 1592 * the duplicated loop is gross, but it was the only way 1593 * to eliminate uninitialized variable warnings 1594 */ 1595 cfh = target_reserve(target, sizeof(struct ckpt_filehdr), &error); 1596 if (cfh) { 1597 cfh->cfh_nfiles = 0; 1598 } 1599 1600 /* 1601 * ignore STDIN/STDERR/STDOUT. 1602 */ 1603 for (i = 3; error == 0 && i < p->p_fd->fd_nfiles; i++) { 1604 fp = holdfp(p->p_fd, i, -1); 1605 if (fp == NULL) 1606 continue; 1607 /* 1608 * XXX Only checkpoint vnodes for now. 1609 */ 1610 if (fp->f_type != DTYPE_VNODE) { 1611 fdrop(fp); 1612 continue; 1613 } 1614 cfi = target_reserve(target, sizeof(struct ckpt_fileinfo), 1615 &error); 1616 if (cfi == NULL) { 1617 fdrop(fp); 1618 continue; 1619 } 1620 cfi->cfi_index = -1; 1621 cfi->cfi_type = fp->f_type; 1622 cfi->cfi_flags = fp->f_flag; 1623 cfi->cfi_offset = fp->f_offset; 1624 cfi->cfi_ckflags = 0; 1625 1626 if (fp == ckfp) 1627 cfi->cfi_ckflags |= CKFIF_ISCKPTFD; 1628 /* f_count and f_msgcount should not be saved/restored */ 1629 /* XXX save cred info */ 1630 1631 switch(fp->f_type) { 1632 case DTYPE_VNODE: 1633 vp = (struct vnode *)fp->f_data; 1634 /* 1635 * it looks like a bug in ptrace is marking 1636 * a non-vnode as a vnode - until we find the 1637 * root cause this will at least prevent 1638 * further panics from truss 1639 */ 1640 if (vp == NULL || vp->v_mount == NULL) 1641 break; 1642 cfh->cfh_nfiles++; 1643 cfi->cfi_index = i; 1644 cfi->cfi_fh.fh_fsid = vp->v_mount->mnt_stat.f_fsid; 1645 error = VFS_VPTOFH(vp, &cfi->cfi_fh.fh_fid); 1646 break; 1647 default: 1648 break; 1649 } 1650 fdrop(fp); 1651 } 1652 return(error); 1653 } 1654 1655 static int 1656 elf_puttextvp(struct proc *p, elf_buf_t target) 1657 { 1658 int error = 0; 1659 int *vn_count; 1660 struct fp_closure fpc; 1661 struct ckpt_vminfo *vminfo; 1662 1663 vminfo = target_reserve(target, sizeof(struct ckpt_vminfo), &error); 1664 if (vminfo != NULL) { 1665 vminfo->cvm_dsize = p->p_vmspace->vm_dsize; 1666 vminfo->cvm_tsize = p->p_vmspace->vm_tsize; 1667 vminfo->cvm_daddr = p->p_vmspace->vm_daddr; 1668 vminfo->cvm_taddr = p->p_vmspace->vm_taddr; 1669 } 1670 1671 fpc.count = 0; 1672 vn_count = target_reserve(target, sizeof(int), &error); 1673 if (target->buf != NULL) { 1674 fpc.vnh = (struct vn_hdr *)(target->buf + target->off); 1675 fpc.vnh_max = fpc.vnh + 1676 (target->off_max - target->off) / sizeof(struct vn_hdr); 1677 error = each_segment(p, cb_put_fp, &fpc, 0); 1678 if (vn_count) 1679 *vn_count = fpc.count; 1680 } else { 1681 error = each_segment(p, cb_fpcount_segment, &fpc.count, 0); 1682 } 1683 target->off += fpc.count * sizeof(struct vn_hdr); 1684 return(error); 1685 } 1686 1687 1688 /* 1689 * Tell kern_execve.c about it, with a little help from the linker. 1690 */ 1691 static struct execsw elf_execsw = {exec_elf_imgact, "ELF"}; 1692 EXEC_SET_ORDERED(elf, elf_execsw, SI_ORDER_FIRST); 1693