1 /*- 2 * Copyright (c) 1995-1996 S�ren 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 withough 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 1.12 2003/10/20 06:50:51 dillon 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/namei.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 55 #include <vm/vm.h> 56 #include <vm/vm_kern.h> 57 #include <vm/vm_param.h> 58 #include <vm/pmap.h> 59 #include <sys/lock.h> 60 #include <vm/vm_map.h> 61 #include <vm/vm_object.h> 62 #include <vm/vm_extern.h> 63 64 #include <machine/elf.h> 65 #include <machine/md_var.h> 66 #include <sys/mount.h> 67 #include <sys/ckpt.h> 68 #define OLD_EI_BRAND 8 69 70 __ElfType(Brandinfo); 71 __ElfType(Auxargs); 72 73 static int elf_check_header (const Elf_Ehdr *hdr); 74 static int elf_freebsd_fixup (register_t **stack_base, 75 struct image_params *imgp); 76 static int elf_load_file (struct proc *p, const char *file, u_long *addr, 77 u_long *entry); 78 static int elf_load_section (struct proc *p, 79 struct vmspace *vmspace, struct vnode *vp, 80 vm_offset_t offset, caddr_t vmaddr, size_t memsz, size_t filsz, 81 vm_prot_t prot); 82 static int exec_elf_imgact (struct image_params *imgp); 83 84 static int elf_trace = 0; 85 SYSCTL_INT(_debug, OID_AUTO, elf_trace, CTLFLAG_RW, &elf_trace, 0, ""); 86 static int elf_legacy_coredump = 0; 87 SYSCTL_INT(_debug, OID_AUTO, elf_legacy_coredump, CTLFLAG_RW, 88 &elf_legacy_coredump, 0, ""); 89 90 static struct sysentvec elf_freebsd_sysvec = { 91 SYS_MAXSYSCALL, 92 sysent, 93 0, 94 0, 95 0, 96 0, 97 0, 98 0, 99 elf_freebsd_fixup, 100 sendsig, 101 sigcode, 102 &szsigcode, 103 0, 104 "FreeBSD ELF", 105 elf_coredump, 106 NULL, 107 MINSIGSTKSZ 108 }; 109 110 static Elf_Brandinfo freebsd_brand_info = { 111 ELFOSABI_FREEBSD, 112 "FreeBSD", 113 "", 114 "/usr/libexec/ld-elf.so.1", 115 &elf_freebsd_sysvec 116 }; 117 static Elf_Brandinfo *elf_brand_list[MAX_BRANDS] = { 118 &freebsd_brand_info, 119 NULL, NULL, NULL, 120 NULL, NULL, NULL, NULL 121 }; 122 123 int 124 elf_insert_brand_entry(Elf_Brandinfo *entry) 125 { 126 int i; 127 128 for (i=1; i<MAX_BRANDS; i++) { 129 if (elf_brand_list[i] == NULL) { 130 elf_brand_list[i] = entry; 131 break; 132 } 133 } 134 if (i == MAX_BRANDS) 135 return -1; 136 return 0; 137 } 138 139 int 140 elf_remove_brand_entry(Elf_Brandinfo *entry) 141 { 142 int i; 143 144 for (i=1; i<MAX_BRANDS; i++) { 145 if (elf_brand_list[i] == entry) { 146 elf_brand_list[i] = NULL; 147 break; 148 } 149 } 150 if (i == MAX_BRANDS) 151 return -1; 152 return 0; 153 } 154 155 int 156 elf_brand_inuse(Elf_Brandinfo *entry) 157 { 158 struct proc *p; 159 int rval = FALSE; 160 161 FOREACH_PROC_IN_SYSTEM(p) { 162 if (p->p_sysent == entry->sysvec) { 163 rval = TRUE; 164 break; 165 } 166 } 167 168 return (rval); 169 } 170 171 static int 172 elf_check_header(const Elf_Ehdr *hdr) 173 { 174 if (!IS_ELF(*hdr) || 175 hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS || 176 hdr->e_ident[EI_DATA] != ELF_TARG_DATA || 177 hdr->e_ident[EI_VERSION] != EV_CURRENT) 178 return ENOEXEC; 179 180 if (!ELF_MACHINE_OK(hdr->e_machine)) 181 return ENOEXEC; 182 183 if (hdr->e_version != ELF_TARG_VER) 184 return ENOEXEC; 185 186 return 0; 187 } 188 189 static int 190 elf_load_section(struct proc *p, struct vmspace *vmspace, struct vnode *vp, 191 vm_offset_t offset, caddr_t vmaddr, size_t memsz, size_t filsz, 192 vm_prot_t prot) 193 { 194 size_t map_len; 195 vm_offset_t map_addr; 196 int error, rv, cow; 197 int count; 198 size_t copy_len; 199 vm_object_t object; 200 vm_offset_t file_addr; 201 vm_offset_t data_buf = 0; 202 203 VOP_GETVOBJECT(vp, &object); 204 error = 0; 205 206 /* 207 * It's necessary to fail if the filsz + offset taken from the 208 * header is greater than the actual file pager object's size. 209 * If we were to allow this, then the vm_map_find() below would 210 * walk right off the end of the file object and into the ether. 211 * 212 * While I'm here, might as well check for something else that 213 * is invalid: filsz cannot be greater than memsz. 214 */ 215 if ((off_t)filsz + offset > object->un_pager.vnp.vnp_size || 216 filsz > memsz) { 217 uprintf("elf_load_section: truncated ELF file\n"); 218 return (ENOEXEC); 219 } 220 221 map_addr = trunc_page((vm_offset_t)vmaddr); 222 file_addr = trunc_page(offset); 223 224 /* 225 * We have two choices. We can either clear the data in the last page 226 * of an oversized mapping, or we can start the anon mapping a page 227 * early and copy the initialized data into that first page. We 228 * choose the second.. 229 */ 230 if (memsz > filsz) 231 map_len = trunc_page(offset+filsz) - file_addr; 232 else 233 map_len = round_page(offset+filsz) - file_addr; 234 235 if (map_len != 0) { 236 vm_object_reference(object); 237 238 /* cow flags: don't dump readonly sections in core */ 239 cow = MAP_COPY_ON_WRITE | MAP_PREFAULT | 240 (prot & VM_PROT_WRITE ? 0 : MAP_DISABLE_COREDUMP); 241 242 count = vm_map_entry_reserve(MAP_RESERVE_COUNT); 243 vm_map_lock(&vmspace->vm_map); 244 rv = vm_map_insert(&vmspace->vm_map, &count, 245 object, 246 file_addr, /* file offset */ 247 map_addr, /* virtual start */ 248 map_addr + map_len,/* virtual end */ 249 prot, 250 VM_PROT_ALL, 251 cow); 252 vm_map_unlock(&vmspace->vm_map); 253 vm_map_entry_release(count); 254 if (rv != KERN_SUCCESS) { 255 vm_object_deallocate(object); 256 return EINVAL; 257 } 258 259 /* we can stop now if we've covered it all */ 260 if (memsz == filsz) { 261 return 0; 262 } 263 } 264 265 266 /* 267 * We have to get the remaining bit of the file into the first part 268 * of the oversized map segment. This is normally because the .data 269 * segment in the file is extended to provide bss. It's a neat idea 270 * to try and save a page, but it's a pain in the behind to implement. 271 */ 272 copy_len = (offset + filsz) - trunc_page(offset + filsz); 273 map_addr = trunc_page((vm_offset_t)vmaddr + filsz); 274 map_len = round_page((vm_offset_t)vmaddr + memsz) - map_addr; 275 276 /* This had damn well better be true! */ 277 if (map_len != 0) { 278 count = vm_map_entry_reserve(MAP_RESERVE_COUNT); 279 vm_map_lock(&vmspace->vm_map); 280 rv = vm_map_insert(&vmspace->vm_map, &count, 281 NULL, 0, 282 map_addr, map_addr + map_len, 283 VM_PROT_ALL, VM_PROT_ALL, 0); 284 vm_map_unlock(&vmspace->vm_map); 285 vm_map_entry_release(count); 286 if (rv != KERN_SUCCESS) { 287 return EINVAL; 288 } 289 } 290 291 if (copy_len != 0) { 292 vm_object_reference(object); 293 rv = vm_map_find(exec_map, 294 object, 295 trunc_page(offset + filsz), 296 &data_buf, 297 PAGE_SIZE, 298 TRUE, 299 VM_PROT_READ, 300 VM_PROT_ALL, 301 MAP_COPY_ON_WRITE | MAP_PREFAULT_PARTIAL); 302 if (rv != KERN_SUCCESS) { 303 vm_object_deallocate(object); 304 return EINVAL; 305 } 306 307 /* send the page fragment to user space */ 308 error = copyout((caddr_t)data_buf, (caddr_t)map_addr, copy_len); 309 vm_map_remove(exec_map, data_buf, data_buf + PAGE_SIZE); 310 if (error) { 311 return (error); 312 } 313 } 314 315 /* 316 * set it to the specified protection 317 */ 318 vm_map_protect(&vmspace->vm_map, map_addr, map_addr + map_len, prot, 319 FALSE); 320 321 return error; 322 } 323 324 /* 325 * Load the file "file" into memory. It may be either a shared object 326 * or an executable. 327 * 328 * The "addr" reference parameter is in/out. On entry, it specifies 329 * the address where a shared object should be loaded. If the file is 330 * an executable, this value is ignored. On exit, "addr" specifies 331 * where the file was actually loaded. 332 * 333 * The "entry" reference parameter is out only. On exit, it specifies 334 * the entry point for the loaded file. 335 */ 336 static int 337 elf_load_file(struct proc *p, const char *file, u_long *addr, u_long *entry) 338 { 339 struct { 340 struct nameidata nd; 341 struct vattr attr; 342 struct image_params image_params; 343 } *tempdata; 344 const Elf_Ehdr *hdr = NULL; 345 const Elf_Phdr *phdr = NULL; 346 struct nameidata *nd; 347 struct vmspace *vmspace = p->p_vmspace; 348 struct vattr *attr; 349 struct image_params *imgp; 350 vm_prot_t prot; 351 u_long rbase; 352 u_long base_addr = 0; 353 int error, i, numsegs; 354 struct thread *td = p->p_thread; 355 356 tempdata = malloc(sizeof(*tempdata), M_TEMP, M_WAITOK); 357 nd = &tempdata->nd; 358 attr = &tempdata->attr; 359 imgp = &tempdata->image_params; 360 361 /* 362 * Initialize part of the common data 363 */ 364 imgp->proc = p; 365 imgp->uap = NULL; 366 imgp->attr = attr; 367 imgp->firstpage = NULL; 368 imgp->image_header = (char *)kmem_alloc_wait(exec_map, PAGE_SIZE); 369 370 if (imgp->image_header == NULL) { 371 nd->ni_vp = NULL; 372 error = ENOMEM; 373 goto fail; 374 } 375 376 NDINIT(nd, NAMEI_LOOKUP, CNP_LOCKLEAF | CNP_FOLLOW, 377 UIO_SYSSPACE, file, td); 378 379 if ((error = namei(nd)) != 0) { 380 nd->ni_vp = NULL; 381 goto fail; 382 } 383 NDFREE(nd, NDF_ONLY_PNBUF); 384 imgp->vp = nd->ni_vp; 385 386 /* 387 * Check permissions, modes, uid, etc on the file, and "open" it. 388 */ 389 error = exec_check_permissions(imgp); 390 if (error) { 391 VOP_UNLOCK(nd->ni_vp, 0, td); 392 goto fail; 393 } 394 395 error = exec_map_first_page(imgp); 396 /* 397 * Also make certain that the interpreter stays the same, so set 398 * its VTEXT flag, too. 399 */ 400 if (error == 0) 401 nd->ni_vp->v_flag |= VTEXT; 402 VOP_UNLOCK(nd->ni_vp, 0, td); 403 if (error) 404 goto fail; 405 406 hdr = (const Elf_Ehdr *)imgp->image_header; 407 if ((error = elf_check_header(hdr)) != 0) 408 goto fail; 409 if (hdr->e_type == ET_DYN) 410 rbase = *addr; 411 else if (hdr->e_type == ET_EXEC) 412 rbase = 0; 413 else { 414 error = ENOEXEC; 415 goto fail; 416 } 417 418 /* Only support headers that fit within first page for now */ 419 if ((hdr->e_phoff > PAGE_SIZE) || 420 (hdr->e_phoff + hdr->e_phentsize * hdr->e_phnum) > PAGE_SIZE) { 421 error = ENOEXEC; 422 goto fail; 423 } 424 425 phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff); 426 427 for (i = 0, numsegs = 0; i < hdr->e_phnum; i++) { 428 if (phdr[i].p_type == PT_LOAD) { /* Loadable segment */ 429 prot = 0; 430 if (phdr[i].p_flags & PF_X) 431 prot |= VM_PROT_EXECUTE; 432 if (phdr[i].p_flags & PF_W) 433 prot |= VM_PROT_WRITE; 434 if (phdr[i].p_flags & PF_R) 435 prot |= VM_PROT_READ; 436 437 error = elf_load_section( 438 p, vmspace, nd->ni_vp, 439 phdr[i].p_offset, 440 (caddr_t)phdr[i].p_vaddr + 441 rbase, 442 phdr[i].p_memsz, 443 phdr[i].p_filesz, prot); 444 if (error != 0) 445 goto fail; 446 /* 447 * Establish the base address if this is the 448 * first segment. 449 */ 450 if (numsegs == 0) 451 base_addr = trunc_page(phdr[i].p_vaddr + rbase); 452 numsegs++; 453 } 454 } 455 *addr = base_addr; 456 *entry=(unsigned long)hdr->e_entry + rbase; 457 458 fail: 459 if (imgp->firstpage) 460 exec_unmap_first_page(imgp); 461 if (imgp->image_header) 462 kmem_free_wakeup(exec_map, (vm_offset_t)imgp->image_header, 463 PAGE_SIZE); 464 if (nd->ni_vp) 465 vrele(nd->ni_vp); 466 467 free(tempdata, M_TEMP); 468 469 return error; 470 } 471 472 /* 473 * non static, as it can be overridden by start_init() 474 */ 475 int fallback_elf_brand = -1; 476 SYSCTL_INT(_kern, OID_AUTO, fallback_elf_brand, CTLFLAG_RW, 477 &fallback_elf_brand, -1, 478 "ELF brand of last resort"); 479 480 static int 481 exec_elf_imgact(struct image_params *imgp) 482 { 483 const Elf_Ehdr *hdr = (const Elf_Ehdr *) imgp->image_header; 484 const Elf_Phdr *phdr; 485 Elf_Auxargs *elf_auxargs = NULL; 486 struct vmspace *vmspace; 487 vm_prot_t prot; 488 u_long text_size = 0, data_size = 0, total_size = 0; 489 u_long text_addr = 0, data_addr = 0; 490 u_long seg_size, seg_addr; 491 u_long addr, entry = 0, proghdr = 0; 492 int error, i; 493 const char *interp = NULL; 494 Elf_Brandinfo *brand_info; 495 char *path; 496 497 /* 498 * Do we have a valid ELF header ? 499 */ 500 if (elf_check_header(hdr) != 0 || hdr->e_type != ET_EXEC) 501 return -1; 502 503 /* 504 * From here on down, we return an errno, not -1, as we've 505 * detected an ELF file. 506 */ 507 508 if ((hdr->e_phoff > PAGE_SIZE) || 509 (hdr->e_phoff + hdr->e_phentsize * hdr->e_phnum) > PAGE_SIZE) { 510 /* Only support headers in first page for now */ 511 return ENOEXEC; 512 } 513 phdr = (const Elf_Phdr*)(imgp->image_header + hdr->e_phoff); 514 515 /* 516 * From this point on, we may have resources that need to be freed. 517 */ 518 519 if ((error = exec_extract_strings(imgp)) != 0) 520 goto fail; 521 522 exec_new_vmspace(imgp); 523 524 /* 525 * Yeah, I'm paranoid. There is every reason in the world to get 526 * VTEXT now since from here on out, there are places we can have 527 * a context switch. Better safe than sorry; I really don't want 528 * the file to change while it's being loaded. 529 */ 530 lwkt_gettoken(&imgp->vp->v_interlock); 531 imgp->vp->v_flag |= VTEXT; 532 lwkt_reltoken(&imgp->vp->v_interlock); 533 534 vmspace = imgp->proc->p_vmspace; 535 536 for (i = 0; i < hdr->e_phnum; i++) { 537 switch(phdr[i].p_type) { 538 539 case PT_LOAD: /* Loadable segment */ 540 prot = 0; 541 if (phdr[i].p_flags & PF_X) 542 prot |= VM_PROT_EXECUTE; 543 if (phdr[i].p_flags & PF_W) 544 prot |= VM_PROT_WRITE; 545 if (phdr[i].p_flags & PF_R) 546 prot |= VM_PROT_READ; 547 548 if ((error = elf_load_section(imgp->proc, 549 vmspace, imgp->vp, 550 phdr[i].p_offset, 551 (caddr_t)phdr[i].p_vaddr, 552 phdr[i].p_memsz, 553 phdr[i].p_filesz, prot)) != 0) 554 goto fail; 555 556 seg_addr = trunc_page(phdr[i].p_vaddr); 557 seg_size = round_page(phdr[i].p_memsz + 558 phdr[i].p_vaddr - seg_addr); 559 560 /* 561 * Is this .text or .data? We can't use 562 * VM_PROT_WRITE or VM_PROT_EXEC, it breaks the 563 * alpha terribly and possibly does other bad 564 * things so we stick to the old way of figuring 565 * it out: If the segment contains the program 566 * entry point, it's a text segment, otherwise it 567 * is a data segment. 568 * 569 * Note that obreak() assumes that data_addr + 570 * data_size == end of data load area, and the ELF 571 * file format expects segments to be sorted by 572 * address. If multiple data segments exist, the 573 * last one will be used. 574 */ 575 if (hdr->e_entry >= phdr[i].p_vaddr && 576 hdr->e_entry < (phdr[i].p_vaddr + 577 phdr[i].p_memsz)) { 578 text_size = seg_size; 579 text_addr = seg_addr; 580 entry = (u_long)hdr->e_entry; 581 } else { 582 data_size = seg_size; 583 data_addr = seg_addr; 584 } 585 total_size += seg_size; 586 587 /* 588 * Check limits. It should be safe to check the 589 * limits after loading the segment since we do 590 * not actually fault in all the segment's pages. 591 */ 592 if (data_size > 593 imgp->proc->p_rlimit[RLIMIT_DATA].rlim_cur || 594 text_size > maxtsiz || 595 total_size > 596 imgp->proc->p_rlimit[RLIMIT_VMEM].rlim_cur) { 597 error = ENOMEM; 598 goto fail; 599 } 600 break; 601 case PT_INTERP: /* Path to interpreter */ 602 if (phdr[i].p_filesz > MAXPATHLEN || 603 phdr[i].p_offset + phdr[i].p_filesz > PAGE_SIZE) { 604 error = ENOEXEC; 605 goto fail; 606 } 607 interp = imgp->image_header + phdr[i].p_offset; 608 break; 609 case PT_PHDR: /* Program header table info */ 610 proghdr = phdr[i].p_vaddr; 611 break; 612 default: 613 break; 614 } 615 } 616 617 vmspace->vm_tsize = text_size >> PAGE_SHIFT; 618 vmspace->vm_taddr = (caddr_t)(uintptr_t)text_addr; 619 vmspace->vm_dsize = data_size >> PAGE_SHIFT; 620 vmspace->vm_daddr = (caddr_t)(uintptr_t)data_addr; 621 622 addr = ELF_RTLD_ADDR(vmspace); 623 624 imgp->entry_addr = entry; 625 626 brand_info = NULL; 627 628 /* We support three types of branding -- (1) the ELF EI_OSABI field 629 * that SCO added to the ELF spec, (2) FreeBSD 3.x's traditional string 630 * branding w/in the ELF header, and (3) path of the `interp_path' 631 * field. We should also look for an ".note.ABI-tag" ELF section now 632 * in all Linux ELF binaries, FreeBSD 4.1+, and some NetBSD ones. 633 */ 634 635 /* If the executable has a brand, search for it in the brand list. */ 636 if (brand_info == NULL) { 637 for (i = 0; i < MAX_BRANDS; i++) { 638 Elf_Brandinfo *bi = elf_brand_list[i]; 639 640 if (bi != NULL && 641 (hdr->e_ident[EI_OSABI] == bi->brand 642 || 0 == 643 strncmp((const char *)&hdr->e_ident[OLD_EI_BRAND], 644 bi->compat_3_brand, strlen(bi->compat_3_brand)))) { 645 brand_info = bi; 646 break; 647 } 648 } 649 } 650 651 /* Lacking a known brand, search for a recognized interpreter. */ 652 if (brand_info == NULL && interp != NULL) { 653 for (i = 0; i < MAX_BRANDS; i++) { 654 Elf_Brandinfo *bi = elf_brand_list[i]; 655 656 if (bi != NULL && 657 strcmp(interp, bi->interp_path) == 0) { 658 brand_info = bi; 659 break; 660 } 661 } 662 } 663 664 /* Lacking a recognized interpreter, try the default brand */ 665 if (brand_info == NULL) { 666 for (i = 0; i < MAX_BRANDS; i++) { 667 Elf_Brandinfo *bi = elf_brand_list[i]; 668 669 if (bi != NULL && fallback_elf_brand == bi->brand) { 670 brand_info = bi; 671 break; 672 } 673 } 674 } 675 676 if (brand_info == NULL) { 677 uprintf("ELF binary type \"%u\" not known.\n", 678 hdr->e_ident[EI_OSABI]); 679 error = ENOEXEC; 680 goto fail; 681 } 682 683 imgp->proc->p_sysent = brand_info->sysvec; 684 if (interp != NULL) { 685 path = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 686 snprintf(path, MAXPATHLEN, "%s%s", 687 brand_info->emul_path, interp); 688 if ((error = elf_load_file(imgp->proc, path, &addr, 689 &imgp->entry_addr)) != 0) { 690 if ((error = elf_load_file(imgp->proc, interp, &addr, 691 &imgp->entry_addr)) != 0) { 692 uprintf("ELF interpreter %s not found\n", path); 693 free(path, M_TEMP); 694 goto fail; 695 } 696 } 697 free(path, M_TEMP); 698 } 699 700 /* 701 * Construct auxargs table (used by the fixup routine) 702 */ 703 elf_auxargs = malloc(sizeof(Elf_Auxargs), M_TEMP, M_WAITOK); 704 elf_auxargs->execfd = -1; 705 elf_auxargs->phdr = proghdr; 706 elf_auxargs->phent = hdr->e_phentsize; 707 elf_auxargs->phnum = hdr->e_phnum; 708 elf_auxargs->pagesz = PAGE_SIZE; 709 elf_auxargs->base = addr; 710 elf_auxargs->flags = 0; 711 elf_auxargs->entry = entry; 712 elf_auxargs->trace = elf_trace; 713 714 imgp->auxargs = elf_auxargs; 715 imgp->interpreted = 0; 716 717 fail: 718 return error; 719 } 720 721 static int 722 elf_freebsd_fixup(register_t **stack_base, struct image_params *imgp) 723 { 724 Elf_Auxargs *args = (Elf_Auxargs *)imgp->auxargs; 725 register_t *pos; 726 727 pos = *stack_base + (imgp->argc + imgp->envc + 2); 728 729 if (args->trace) { 730 AUXARGS_ENTRY(pos, AT_DEBUG, 1); 731 } 732 if (args->execfd != -1) { 733 AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd); 734 } 735 AUXARGS_ENTRY(pos, AT_PHDR, args->phdr); 736 AUXARGS_ENTRY(pos, AT_PHENT, args->phent); 737 AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum); 738 AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz); 739 AUXARGS_ENTRY(pos, AT_FLAGS, args->flags); 740 AUXARGS_ENTRY(pos, AT_ENTRY, args->entry); 741 AUXARGS_ENTRY(pos, AT_BASE, args->base); 742 AUXARGS_ENTRY(pos, AT_NULL, 0); 743 744 free(imgp->auxargs, M_TEMP); 745 imgp->auxargs = NULL; 746 747 (*stack_base)--; 748 suword(*stack_base, (long) imgp->argc); 749 return 0; 750 } 751 752 /* 753 * Code for generating ELF core dumps. 754 */ 755 756 typedef void (*segment_callback) (vm_map_entry_t, void *); 757 758 /* Closure for cb_put_phdr(). */ 759 struct phdr_closure { 760 Elf_Phdr *phdr; /* Program header to fill in */ 761 Elf_Off offset; /* Offset of segment in core file */ 762 }; 763 764 /* Closure for cb_size_segment(). */ 765 struct sseg_closure { 766 int count; /* Count of writable segments. */ 767 size_t size; /* Total size of all writable segments. */ 768 }; 769 770 struct fp_closure { 771 struct vn_hdr *vnh; 772 int count; 773 struct stat *sb; 774 }; 775 776 777 778 static void cb_put_phdr (vm_map_entry_t, void *); 779 static void cb_size_segment (vm_map_entry_t, void *); 780 static void cb_fpcount_segment(vm_map_entry_t, void *); 781 static void cb_put_fp(vm_map_entry_t, void *); 782 783 784 static void each_segment (struct proc *, segment_callback, 785 void *, int); 786 static int elf_corehdr (struct proc *, struct file *, struct ucred *, 787 int, void *, size_t); 788 static void elf_puthdr (struct proc *, void *, size_t *, 789 const prstatus_t *, const prfpregset_t *, const prpsinfo_t *, int); 790 static void elf_putnote (void *, size_t *, const char *, int, 791 const void *, size_t); 792 793 static void elf_putsigs(struct proc *, void *, int *); 794 795 static void elf_puttextvp(struct proc *, void *, int *); 796 static void elf_putfiles(struct proc *, void *, int *); 797 798 799 extern int osreldate; 800 801 int 802 elf_coredump(struct proc *p, struct vnode *vp, off_t limit) 803 { 804 struct file *fp; 805 int error; 806 807 if ((error = falloc(NULL, &fp, NULL)) != 0) 808 return (error); 809 fsetcred(fp, p->p_ucred); 810 811 fp->f_data = (caddr_t)vp; 812 fp->f_flag = O_CREAT|O_WRONLY|O_NOFOLLOW; 813 fp->f_ops = &vnops; 814 fp->f_type = DTYPE_VNODE; 815 VOP_UNLOCK(vp, 0, p->p_thread); 816 817 error = generic_elf_coredump(p, fp, limit); 818 819 fp->f_data = NULL; 820 fp->f_flag = 0; 821 fp->f_ops = &badfileops; 822 fp->f_type = 0; 823 fdrop(fp, p->p_thread); 824 return (error); 825 } 826 827 int 828 generic_elf_coredump(struct proc *p, struct file *fp, off_t limit) 829 { 830 831 struct ucred *cred = p->p_ucred; 832 int error = 0; 833 struct sseg_closure seginfo; 834 void *hdr; 835 size_t hdrsize; 836 837 if (!fp) 838 printf("can't dump core - null fp\n"); 839 /* Size the program segments. */ 840 seginfo.count = 0; 841 seginfo.size = 0; 842 each_segment(p, cb_size_segment, &seginfo, 1); 843 844 /* 845 * Calculate the size of the core file header area by making 846 * a dry run of generating it. Nothing is written, but the 847 * size is calculated. 848 */ 849 850 hdrsize = 0; 851 elf_puthdr(p, (void *)NULL, &hdrsize, 852 (const prstatus_t *)NULL, (const prfpregset_t *)NULL, 853 (const prpsinfo_t *)NULL, seginfo.count); 854 855 if (hdrsize + seginfo.size >= limit) 856 return (EFAULT); 857 858 /* 859 * Allocate memory for building the header, fill it up, 860 * and write it out. 861 */ 862 hdr = malloc(hdrsize, M_TEMP, M_WAITOK); 863 if (hdr == NULL) { 864 return EINVAL; 865 } 866 error = elf_corehdr(p, fp, cred, seginfo.count, hdr, hdrsize); 867 868 /* Write the contents of all of the writable segments. */ 869 if (error == 0) { 870 Elf_Phdr *php; 871 int i; 872 int nbytes; 873 874 php = (Elf_Phdr *)((char *)hdr + sizeof(Elf_Ehdr)) + 1; 875 for (i = 0; i < seginfo.count; i++) { 876 error = fp_write(fp, (caddr_t)php->p_vaddr, 877 php->p_filesz, &nbytes); 878 if (error != 0) 879 break; 880 php++; 881 } 882 } 883 free(hdr, M_TEMP); 884 885 return error; 886 } 887 888 /* 889 * A callback for each_segment() to write out the segment's 890 * program header entry. 891 */ 892 static void 893 cb_put_phdr(vm_map_entry_t entry, void *closure) 894 { 895 struct phdr_closure *phc = (struct phdr_closure *)closure; 896 Elf_Phdr *phdr = phc->phdr; 897 898 phc->offset = round_page(phc->offset); 899 900 phdr->p_type = PT_LOAD; 901 phdr->p_offset = phc->offset; 902 phdr->p_vaddr = entry->start; 903 phdr->p_paddr = 0; 904 phdr->p_filesz = phdr->p_memsz = entry->end - entry->start; 905 phdr->p_align = PAGE_SIZE; 906 phdr->p_flags = 0; 907 if (entry->protection & VM_PROT_READ) 908 phdr->p_flags |= PF_R; 909 if (entry->protection & VM_PROT_WRITE) 910 phdr->p_flags |= PF_W; 911 if (entry->protection & VM_PROT_EXECUTE) 912 phdr->p_flags |= PF_X; 913 914 phc->offset += phdr->p_filesz; 915 phc->phdr++; 916 } 917 918 /* 919 * A callback for each_writable_segment() to gather information about 920 * the number of segments and their total size. 921 */ 922 static void 923 cb_size_segment(vm_map_entry_t entry, void *closure) 924 { 925 struct sseg_closure *ssc = (struct sseg_closure *)closure; 926 927 ssc->count++; 928 ssc->size += entry->end - entry->start; 929 } 930 931 /* 932 * A callback for each_segment() to gather information about 933 * the number of text segments. 934 */ 935 static void 936 cb_fpcount_segment(vm_map_entry_t entry, void *closure) 937 { 938 int *count = (int *)closure; 939 if (entry->object.vm_object->type == OBJT_VNODE) 940 ++*count; 941 } 942 943 static void 944 cb_put_fp(vm_map_entry_t entry, void *closure) 945 { 946 struct fp_closure *fpc = (struct fp_closure *)closure; 947 struct vn_hdr *vnh = fpc->vnh; 948 Elf_Phdr *phdr = &vnh->vnh_phdr; 949 struct vnode *vp; 950 int error; 951 952 if (entry->object.vm_object->type == OBJT_VNODE) { 953 vp = (struct vnode *)entry->object.vm_object->handle; 954 955 vnh->vnh_fh.fh_fsid = vp->v_mount->mnt_stat.f_fsid; 956 error = VFS_VPTOFH(vp, &vnh->vnh_fh.fh_fid); 957 if (error) 958 return; 959 960 961 phdr->p_type = PT_LOAD; 962 phdr->p_offset = 0; /* not written to core */ 963 phdr->p_vaddr = entry->start; 964 phdr->p_paddr = 0; 965 phdr->p_filesz = phdr->p_memsz = entry->end - entry->start; 966 phdr->p_align = PAGE_SIZE; 967 phdr->p_flags = 0; 968 if (entry->protection & VM_PROT_READ) 969 phdr->p_flags |= PF_R; 970 if (entry->protection & VM_PROT_WRITE) 971 phdr->p_flags |= PF_W; 972 if (entry->protection & VM_PROT_EXECUTE) 973 phdr->p_flags |= PF_X; 974 ++fpc->vnh; 975 ++fpc->count; 976 } 977 } 978 979 980 981 982 /* 983 * For each writable segment in the process's memory map, call the given 984 * function with a pointer to the map entry and some arbitrary 985 * caller-supplied data. 986 */ 987 static void 988 each_segment(struct proc *p, segment_callback func, void *closure, int writable) 989 { 990 vm_map_t map = &p->p_vmspace->vm_map; 991 vm_map_entry_t entry; 992 993 for (entry = map->header.next; entry != &map->header; 994 entry = entry->next) { 995 vm_object_t obj; 996 997 /* 998 * Don't dump inaccessible mappings, deal with legacy 999 * coredump mode. 1000 * 1001 * Note that read-only segments related to the elf binary 1002 * are marked MAP_ENTRY_NOCOREDUMP now so we no longer 1003 * need to arbitrarily ignore such segments. 1004 */ 1005 if (elf_legacy_coredump) { 1006 if (writable && (entry->protection & VM_PROT_RW) != VM_PROT_RW) 1007 continue; 1008 } else { 1009 if (writable && (entry->protection & VM_PROT_ALL) == 0) 1010 continue; 1011 } 1012 1013 /* 1014 * Dont include memory segment in the coredump if 1015 * MAP_NOCORE is set in mmap(2) or MADV_NOCORE in 1016 * madvise(2). Do not dump submaps (i.e. parts of the 1017 * kernel map). 1018 */ 1019 if (writable && entry->eflags & (MAP_ENTRY_NOCOREDUMP|MAP_ENTRY_IS_SUB_MAP)) 1020 continue; 1021 1022 if ((obj = entry->object.vm_object) == NULL) 1023 continue; 1024 1025 /* Find the deepest backing object. */ 1026 while (obj->backing_object != NULL) 1027 obj = obj->backing_object; 1028 1029 /* Ignore memory-mapped devices and such things. */ 1030 if (obj->type != OBJT_DEFAULT && 1031 obj->type != OBJT_SWAP && 1032 obj->type != OBJT_VNODE) 1033 continue; 1034 1035 (*func)(entry, closure); 1036 } 1037 } 1038 1039 /* 1040 * Write the core file header to the file, including padding up to 1041 * the page boundary. 1042 */ 1043 static int 1044 elf_corehdr(struct proc *p, struct file *fp, struct ucred *cred, int numsegs, 1045 void *hdr, size_t hdrsize) 1046 { 1047 struct { 1048 prstatus_t status; 1049 prfpregset_t fpregset; 1050 prpsinfo_t psinfo; 1051 } *tempdata; 1052 size_t off; 1053 prstatus_t *status; 1054 prfpregset_t *fpregset; 1055 prpsinfo_t *psinfo; 1056 int nbytes; 1057 tempdata = malloc(sizeof(*tempdata), M_TEMP, M_ZERO | M_WAITOK); 1058 status = &tempdata->status; 1059 fpregset = &tempdata->fpregset; 1060 psinfo = &tempdata->psinfo; 1061 1062 /* Gather the information for the header. */ 1063 status->pr_version = PRSTATUS_VERSION; 1064 status->pr_statussz = sizeof(prstatus_t); 1065 status->pr_gregsetsz = sizeof(gregset_t); 1066 status->pr_fpregsetsz = sizeof(fpregset_t); 1067 status->pr_osreldate = osreldate; 1068 status->pr_cursig = p->p_sig; 1069 status->pr_pid = p->p_pid; 1070 fill_regs(p, &status->pr_reg); 1071 1072 fill_fpregs(p, fpregset); 1073 1074 psinfo->pr_version = PRPSINFO_VERSION; 1075 psinfo->pr_psinfosz = sizeof(prpsinfo_t); 1076 strncpy(psinfo->pr_fname, p->p_comm, sizeof(psinfo->pr_fname) - 1); 1077 1078 /* XXX - We don't fill in the command line arguments properly yet. */ 1079 strncpy(psinfo->pr_psargs, p->p_comm, PRARGSZ); 1080 1081 /* Fill in the header. */ 1082 bzero(hdr, hdrsize); 1083 off = 0; 1084 elf_puthdr(p, hdr, &off, status, fpregset, psinfo, numsegs); 1085 1086 free(tempdata, M_TEMP); 1087 1088 /* Write it to the core file. */ 1089 return fp_write(fp, hdr, hdrsize, &nbytes); 1090 } 1091 1092 static void 1093 elf_puthdr(struct proc *p, void *dst, size_t *off, const prstatus_t *status, 1094 const prfpregset_t *fpregset, const prpsinfo_t *psinfo, int numsegs) 1095 { 1096 size_t ehoff; 1097 size_t phoff; 1098 size_t noteoff; 1099 size_t notesz; 1100 1101 ehoff = *off; 1102 *off += sizeof(Elf_Ehdr); 1103 1104 phoff = *off; 1105 *off += (numsegs + 1) * sizeof(Elf_Phdr); 1106 1107 noteoff = *off; 1108 elf_putnote(dst, off, "FreeBSD", NT_PRSTATUS, status, 1109 sizeof *status); 1110 elf_putnote(dst, off, "FreeBSD", NT_FPREGSET, fpregset, 1111 sizeof *fpregset); 1112 elf_putnote(dst, off, "FreeBSD", NT_PRPSINFO, psinfo, 1113 sizeof *psinfo); 1114 notesz = *off - noteoff; 1115 1116 /* put extra cruft for dumping process state here 1117 * - we really want it be before all the program 1118 * mappings 1119 * - we just need to update the offset accordingly 1120 * and GDB will be none the wiser. 1121 */ 1122 elf_puttextvp(p, dst, off); 1123 elf_putsigs(p, dst, off); 1124 elf_putfiles(p, dst, off); 1125 1126 /* Align up to a page boundary for the program segments. */ 1127 *off = round_page(*off); 1128 1129 if (dst != NULL) { 1130 Elf_Ehdr *ehdr; 1131 Elf_Phdr *phdr; 1132 struct phdr_closure phc; 1133 1134 /* 1135 * Fill in the ELF header. 1136 */ 1137 ehdr = (Elf_Ehdr *)((char *)dst + ehoff); 1138 ehdr->e_ident[EI_MAG0] = ELFMAG0; 1139 ehdr->e_ident[EI_MAG1] = ELFMAG1; 1140 ehdr->e_ident[EI_MAG2] = ELFMAG2; 1141 ehdr->e_ident[EI_MAG3] = ELFMAG3; 1142 ehdr->e_ident[EI_CLASS] = ELF_CLASS; 1143 ehdr->e_ident[EI_DATA] = ELF_DATA; 1144 ehdr->e_ident[EI_VERSION] = EV_CURRENT; 1145 ehdr->e_ident[EI_OSABI] = ELFOSABI_FREEBSD; 1146 ehdr->e_ident[EI_ABIVERSION] = 0; 1147 ehdr->e_ident[EI_PAD] = 0; 1148 ehdr->e_type = ET_CORE; 1149 ehdr->e_machine = ELF_ARCH; 1150 ehdr->e_version = EV_CURRENT; 1151 ehdr->e_entry = 0; 1152 ehdr->e_phoff = phoff; 1153 ehdr->e_flags = 0; 1154 ehdr->e_ehsize = sizeof(Elf_Ehdr); 1155 ehdr->e_phentsize = sizeof(Elf_Phdr); 1156 ehdr->e_phnum = numsegs + 1; 1157 ehdr->e_shentsize = sizeof(Elf_Shdr); 1158 ehdr->e_shnum = 0; 1159 ehdr->e_shstrndx = SHN_UNDEF; 1160 1161 /* 1162 * Fill in the program header entries. 1163 */ 1164 phdr = (Elf_Phdr *)((char *)dst + phoff); 1165 1166 /* The note segement. */ 1167 phdr->p_type = PT_NOTE; 1168 phdr->p_offset = noteoff; 1169 phdr->p_vaddr = 0; 1170 phdr->p_paddr = 0; 1171 phdr->p_filesz = notesz; 1172 phdr->p_memsz = 0; 1173 phdr->p_flags = 0; 1174 phdr->p_align = 0; 1175 phdr++; 1176 1177 /* All the writable segments from the program. */ 1178 phc.phdr = phdr; 1179 phc.offset = *off; 1180 each_segment(p, cb_put_phdr, &phc, 1); 1181 } 1182 } 1183 1184 static void 1185 elf_putnote(void *dst, size_t *off, const char *name, int type, 1186 const void *desc, size_t descsz) 1187 { 1188 Elf_Note note; 1189 1190 note.n_namesz = strlen(name) + 1; 1191 note.n_descsz = descsz; 1192 note.n_type = type; 1193 if (dst != NULL) 1194 bcopy(¬e, (char *)dst + *off, sizeof note); 1195 *off += sizeof note; 1196 if (dst != NULL) 1197 bcopy(name, (char *)dst + *off, note.n_namesz); 1198 *off += roundup2(note.n_namesz, sizeof(Elf_Size)); 1199 if (dst != NULL) 1200 bcopy(desc, (char *)dst + *off, note.n_descsz); 1201 *off += roundup2(note.n_descsz, sizeof(Elf_Size)); 1202 } 1203 1204 1205 static void 1206 elf_putsigs(struct proc *p, void *dst, int *off) 1207 { 1208 struct ckpt_siginfo *csi; 1209 if (dst == NULL) { 1210 *off += sizeof(struct ckpt_siginfo); 1211 return; 1212 } 1213 csi = (struct ckpt_siginfo *)((char *)dst + *off); 1214 1215 csi->csi_ckptpisz = sizeof(struct ckpt_siginfo); 1216 bcopy(p->p_procsig, &csi->csi_procsig, sizeof(struct procsig)); 1217 bcopy(p->p_procsig->ps_sigacts, &csi->csi_sigacts, sizeof(struct sigacts)); 1218 bcopy(&p->p_realtimer, &csi->csi_itimerval, sizeof(struct itimerval)); 1219 csi->csi_sigparent = p->p_sigparent; 1220 *off += sizeof(struct ckpt_siginfo); 1221 } 1222 1223 static void 1224 elf_putfiles(struct proc *p, void *dst, int *off) 1225 { 1226 int i, error; 1227 struct ckpt_filehdr *cfh = NULL; 1228 struct ckpt_fileinfo *cfi; 1229 struct file *fp; 1230 struct vnode *vp; 1231 /* 1232 * the duplicated loop is gross, but it was the only way 1233 * to eliminate uninitialized variable warnings 1234 */ 1235 if (dst) { 1236 cfh = (struct ckpt_filehdr *)((char *)dst + *off); 1237 cfh->cfh_nfiles = 0; 1238 } 1239 *off += sizeof(struct ckpt_filehdr); 1240 1241 /* 1242 * ignore STDIN/STDERR/STDOUT 1243 */ 1244 for (i = 3; i < p->p_fd->fd_nfiles; i++) { 1245 if ((fp = p->p_fd->fd_ofiles[i]) == NULL) 1246 continue; 1247 if (fp->f_type != DTYPE_VNODE) 1248 continue; 1249 if (dst) { 1250 cfh->cfh_nfiles++; 1251 cfi = (struct ckpt_fileinfo *)((char *)dst + *off); 1252 cfi->cfi_index = i; 1253 cfi->cfi_flags = fp->f_flag; 1254 cfi->cfi_offset = fp->f_offset; 1255 vp = (struct vnode *)fp->f_data; 1256 cfi->cfi_fh.fh_fsid = vp->v_mount->mnt_stat.f_fsid; 1257 error = VFS_VPTOFH(vp, &cfi->cfi_fh.fh_fid); 1258 } 1259 *off += sizeof(struct ckpt_fileinfo); 1260 } 1261 } 1262 1263 static void 1264 elf_puttextvp(struct proc *p, void *dst, int *off) 1265 { 1266 int *vn_count; 1267 struct fp_closure fpc; 1268 struct ckpt_vminfo *vminfo; 1269 1270 vminfo = (struct ckpt_vminfo *)((char *)dst + *off); 1271 if (dst != NULL) { 1272 vminfo->cvm_dsize = p->p_vmspace->vm_dsize; 1273 vminfo->cvm_tsize = p->p_vmspace->vm_tsize; 1274 vminfo->cvm_daddr = p->p_vmspace->vm_daddr; 1275 vminfo->cvm_taddr = p->p_vmspace->vm_taddr; 1276 } 1277 *off += sizeof(*vminfo); 1278 1279 vn_count = (int *)((char *)dst + *off); 1280 *off += sizeof(int); 1281 1282 fpc.vnh = (struct vn_hdr *)((char *)dst + *off); 1283 fpc.count = 0; 1284 if (dst != NULL) { 1285 each_segment(p, cb_put_fp, &fpc, 0); 1286 *vn_count = fpc.count; 1287 } else { 1288 each_segment(p, cb_fpcount_segment, &fpc.count, 0); 1289 } 1290 *off += fpc.count * sizeof(struct vn_hdr); 1291 } 1292 1293 1294 /* 1295 * Tell kern_execve.c about it, with a little help from the linker. 1296 */ 1297 static struct execsw elf_execsw = {exec_elf_imgact, "ELF"}; 1298 EXEC_SET(elf, elf_execsw); 1299