Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)
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FreeBSD/Linux Kernel Cross Reference
sys/kern/imgact_elf.c
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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: releng/8.3/sys/kern/imgact_elf.c 217442 2011-01-15 09:25:19Z kib $"); 33 34 #include "opt_compat.h" 35 36 #include <sys/param.h> 37 #include <sys/exec.h> 38 #include <sys/fcntl.h> 39 #include <sys/imgact.h> 40 #include <sys/imgact_elf.h> 41 #include <sys/kernel.h> 42 #include <sys/lock.h> 43 #include <sys/malloc.h> 44 #include <sys/mount.h> 45 #include <sys/mutex.h> 46 #include <sys/mman.h> 47 #include <sys/namei.h> 48 #include <sys/pioctl.h> 49 #include <sys/proc.h> 50 #include <sys/procfs.h> 51 #include <sys/resourcevar.h> 52 #include <sys/sf_buf.h> 53 #include <sys/systm.h> 54 #include <sys/signalvar.h> 55 #include <sys/stat.h> 56 #include <sys/sx.h> 57 #include <sys/syscall.h> 58 #include <sys/sysctl.h> 59 #include <sys/sysent.h> 60 #include <sys/vnode.h> 61 62 #include <vm/vm.h> 63 #include <vm/vm_kern.h> 64 #include <vm/vm_param.h> 65 #include <vm/pmap.h> 66 #include <vm/vm_map.h> 67 #include <vm/vm_object.h> 68 #include <vm/vm_extern.h> 69 70 #include <machine/elf.h> 71 #include <machine/md_var.h> 72 73 #define OLD_EI_BRAND 8 74 75 static int __elfN(check_header)(const Elf_Ehdr *hdr); 76 static Elf_Brandinfo *__elfN(get_brandinfo)(struct image_params *imgp, 77 const char *interp, int32_t *osrel); 78 static int __elfN(load_file)(struct proc *p, const char *file, u_long *addr, 79 u_long *entry, size_t pagesize); 80 static int __elfN(load_section)(struct vmspace *vmspace, vm_object_t object, 81 vm_offset_t offset, caddr_t vmaddr, size_t memsz, size_t filsz, 82 vm_prot_t prot, size_t pagesize); 83 static int __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp); 84 static boolean_t __elfN(freebsd_trans_osrel)(const Elf_Note *note, 85 int32_t *osrel); 86 static boolean_t kfreebsd_trans_osrel(const Elf_Note *note, int32_t *osrel); 87 static boolean_t __elfN(check_note)(struct image_params *imgp, 88 Elf_Brandnote *checknote, int32_t *osrel); 89 static vm_prot_t __elfN(trans_prot)(Elf_Word); 90 static Elf_Word __elfN(untrans_prot)(vm_prot_t); 91 92 SYSCTL_NODE(_kern, OID_AUTO, __CONCAT(elf, __ELF_WORD_SIZE), CTLFLAG_RW, 0, 93 ""); 94 95 int __elfN(fallback_brand) = -1; 96 SYSCTL_INT(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO, 97 fallback_brand, CTLFLAG_RW, &__elfN(fallback_brand), 0, 98 __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) " brand of last resort"); 99 TUNABLE_INT("kern.elf" __XSTRING(__ELF_WORD_SIZE) ".fallback_brand", 100 &__elfN(fallback_brand)); 101 102 static int elf_legacy_coredump = 0; 103 SYSCTL_INT(_debug, OID_AUTO, __elfN(legacy_coredump), CTLFLAG_RW, 104 &elf_legacy_coredump, 0, ""); 105 106 static Elf_Brandinfo *elf_brand_list[MAX_BRANDS]; 107 108 #define trunc_page_ps(va, ps) ((va) & ~(ps - 1)) 109 #define round_page_ps(va, ps) (((va) + (ps - 1)) & ~(ps - 1)) 110 #define aligned(a, t) (trunc_page_ps((u_long)(a), sizeof(t)) == (u_long)(a)) 111 112 static const char FREEBSD_ABI_VENDOR[] = "FreeBSD"; 113 114 Elf_Brandnote __elfN(freebsd_brandnote) = { 115 .hdr.n_namesz = sizeof(FREEBSD_ABI_VENDOR), 116 .hdr.n_descsz = sizeof(int32_t), 117 .hdr.n_type = 1, 118 .vendor = FREEBSD_ABI_VENDOR, 119 .flags = BN_TRANSLATE_OSREL, 120 .trans_osrel = __elfN(freebsd_trans_osrel) 121 }; 122 123 static boolean_t 124 __elfN(freebsd_trans_osrel)(const Elf_Note *note, int32_t *osrel) 125 { 126 uintptr_t p; 127 128 p = (uintptr_t)(note + 1); 129 p += roundup2(note->n_namesz, sizeof(Elf32_Addr)); 130 *osrel = *(const int32_t *)(p); 131 132 return (TRUE); 133 } 134 135 static const char GNU_ABI_VENDOR[] = "GNU"; 136 static int GNU_KFREEBSD_ABI_DESC = 3; 137 138 Elf_Brandnote __elfN(kfreebsd_brandnote) = { 139 .hdr.n_namesz = sizeof(GNU_ABI_VENDOR), 140 .hdr.n_descsz = 16, /* XXX at least 16 */ 141 .hdr.n_type = 1, 142 .vendor = GNU_ABI_VENDOR, 143 .flags = BN_TRANSLATE_OSREL, 144 .trans_osrel = kfreebsd_trans_osrel 145 }; 146 147 static boolean_t 148 kfreebsd_trans_osrel(const Elf_Note *note, int32_t *osrel) 149 { 150 const Elf32_Word *desc; 151 uintptr_t p; 152 153 p = (uintptr_t)(note + 1); 154 p += roundup2(note->n_namesz, sizeof(Elf32_Addr)); 155 156 desc = (const Elf32_Word *)p; 157 if (desc[0] != GNU_KFREEBSD_ABI_DESC) 158 return (FALSE); 159 160 /* 161 * Debian GNU/kFreeBSD embed the earliest compatible kernel version 162 * (__FreeBSD_version: <major><two digit minor>Rxx) in the LSB way. 163 */ 164 *osrel = desc[1] * 100000 + desc[2] * 1000 + desc[3]; 165 166 return (TRUE); 167 } 168 169 int 170 __elfN(insert_brand_entry)(Elf_Brandinfo *entry) 171 { 172 int i; 173 174 for (i = 0; i < MAX_BRANDS; i++) { 175 if (elf_brand_list[i] == NULL) { 176 elf_brand_list[i] = entry; 177 break; 178 } 179 } 180 if (i == MAX_BRANDS) { 181 printf("WARNING: %s: could not insert brandinfo entry: %p\n", 182 __func__, entry); 183 return (-1); 184 } 185 return (0); 186 } 187 188 int 189 __elfN(remove_brand_entry)(Elf_Brandinfo *entry) 190 { 191 int i; 192 193 for (i = 0; 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 int 205 __elfN(brand_inuse)(Elf_Brandinfo *entry) 206 { 207 struct proc *p; 208 int rval = FALSE; 209 210 sx_slock(&allproc_lock); 211 FOREACH_PROC_IN_SYSTEM(p) { 212 if (p->p_sysent == entry->sysvec) { 213 rval = TRUE; 214 break; 215 } 216 } 217 sx_sunlock(&allproc_lock); 218 219 return (rval); 220 } 221 222 static Elf_Brandinfo * 223 __elfN(get_brandinfo)(struct image_params *imgp, const char *interp, 224 int32_t *osrel) 225 { 226 const Elf_Ehdr *hdr = (const Elf_Ehdr *)imgp->image_header; 227 Elf_Brandinfo *bi; 228 boolean_t ret; 229 int i; 230 231 /* 232 * We support four types of branding -- (1) the ELF EI_OSABI field 233 * that SCO added to the ELF spec, (2) FreeBSD 3.x's traditional string 234 * branding w/in the ELF header, (3) path of the `interp_path' 235 * field, and (4) the ".note.ABI-tag" ELF section. 236 */ 237 238 /* Look for an ".note.ABI-tag" ELF section */ 239 for (i = 0; i < MAX_BRANDS; i++) { 240 bi = elf_brand_list[i]; 241 if (bi == NULL) 242 continue; 243 if (hdr->e_machine == bi->machine && (bi->flags & 244 (BI_BRAND_NOTE|BI_BRAND_NOTE_MANDATORY)) != 0) { 245 ret = __elfN(check_note)(imgp, bi->brand_note, osrel); 246 if (ret) 247 return (bi); 248 } 249 } 250 251 /* If the executable has a brand, search for it in the brand list. */ 252 for (i = 0; i < MAX_BRANDS; i++) { 253 bi = elf_brand_list[i]; 254 if (bi == NULL || bi->flags & BI_BRAND_NOTE_MANDATORY) 255 continue; 256 if (hdr->e_machine == bi->machine && 257 (hdr->e_ident[EI_OSABI] == bi->brand || 258 strncmp((const char *)&hdr->e_ident[OLD_EI_BRAND], 259 bi->compat_3_brand, strlen(bi->compat_3_brand)) == 0)) 260 return (bi); 261 } 262 263 /* Lacking a known brand, search for a recognized interpreter. */ 264 if (interp != NULL) { 265 for (i = 0; i < MAX_BRANDS; i++) { 266 bi = elf_brand_list[i]; 267 if (bi == NULL || bi->flags & BI_BRAND_NOTE_MANDATORY) 268 continue; 269 if (hdr->e_machine == bi->machine && 270 strcmp(interp, bi->interp_path) == 0) 271 return (bi); 272 } 273 } 274 275 /* Lacking a recognized interpreter, try the default brand */ 276 for (i = 0; i < MAX_BRANDS; i++) { 277 bi = elf_brand_list[i]; 278 if (bi == NULL || bi->flags & BI_BRAND_NOTE_MANDATORY) 279 continue; 280 if (hdr->e_machine == bi->machine && 281 __elfN(fallback_brand) == bi->brand) 282 return (bi); 283 } 284 return (NULL); 285 } 286 287 static int 288 __elfN(check_header)(const Elf_Ehdr *hdr) 289 { 290 Elf_Brandinfo *bi; 291 int i; 292 293 if (!IS_ELF(*hdr) || 294 hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS || 295 hdr->e_ident[EI_DATA] != ELF_TARG_DATA || 296 hdr->e_ident[EI_VERSION] != EV_CURRENT || 297 hdr->e_phentsize != sizeof(Elf_Phdr) || 298 hdr->e_version != ELF_TARG_VER) 299 return (ENOEXEC); 300 301 /* 302 * Make sure we have at least one brand for this machine. 303 */ 304 305 for (i = 0; i < MAX_BRANDS; i++) { 306 bi = elf_brand_list[i]; 307 if (bi != NULL && bi->machine == hdr->e_machine) 308 break; 309 } 310 if (i == MAX_BRANDS) 311 return (ENOEXEC); 312 313 return (0); 314 } 315 316 static int 317 __elfN(map_partial)(vm_map_t map, vm_object_t object, vm_ooffset_t offset, 318 vm_offset_t start, vm_offset_t end, vm_prot_t prot) 319 { 320 struct sf_buf *sf; 321 int error; 322 vm_offset_t off; 323 324 /* 325 * Create the page if it doesn't exist yet. Ignore errors. 326 */ 327 vm_map_lock(map); 328 vm_map_insert(map, NULL, 0, trunc_page(start), round_page(end), 329 VM_PROT_ALL, VM_PROT_ALL, 0); 330 vm_map_unlock(map); 331 332 /* 333 * Find the page from the underlying object. 334 */ 335 if (object) { 336 sf = vm_imgact_map_page(object, offset); 337 if (sf == NULL) 338 return (KERN_FAILURE); 339 off = offset - trunc_page(offset); 340 error = copyout((caddr_t)sf_buf_kva(sf) + off, (caddr_t)start, 341 end - start); 342 vm_imgact_unmap_page(sf); 343 if (error) { 344 return (KERN_FAILURE); 345 } 346 } 347 348 return (KERN_SUCCESS); 349 } 350 351 static int 352 __elfN(map_insert)(vm_map_t map, vm_object_t object, vm_ooffset_t offset, 353 vm_offset_t start, vm_offset_t end, vm_prot_t prot, int cow) 354 { 355 struct sf_buf *sf; 356 vm_offset_t off; 357 vm_size_t sz; 358 int error, rv; 359 360 if (start != trunc_page(start)) { 361 rv = __elfN(map_partial)(map, object, offset, start, 362 round_page(start), prot); 363 if (rv) 364 return (rv); 365 offset += round_page(start) - start; 366 start = round_page(start); 367 } 368 if (end != round_page(end)) { 369 rv = __elfN(map_partial)(map, object, offset + 370 trunc_page(end) - start, trunc_page(end), end, prot); 371 if (rv) 372 return (rv); 373 end = trunc_page(end); 374 } 375 if (end > start) { 376 if (offset & PAGE_MASK) { 377 /* 378 * The mapping is not page aligned. This means we have 379 * to copy the data. Sigh. 380 */ 381 rv = vm_map_find(map, NULL, 0, &start, end - start, 382 FALSE, prot | VM_PROT_WRITE, VM_PROT_ALL, 0); 383 if (rv) 384 return (rv); 385 if (object == NULL) 386 return (KERN_SUCCESS); 387 for (; start < end; start += sz) { 388 sf = vm_imgact_map_page(object, offset); 389 if (sf == NULL) 390 return (KERN_FAILURE); 391 off = offset - trunc_page(offset); 392 sz = end - start; 393 if (sz > PAGE_SIZE - off) 394 sz = PAGE_SIZE - off; 395 error = copyout((caddr_t)sf_buf_kva(sf) + off, 396 (caddr_t)start, sz); 397 vm_imgact_unmap_page(sf); 398 if (error) { 399 return (KERN_FAILURE); 400 } 401 offset += sz; 402 } 403 rv = KERN_SUCCESS; 404 } else { 405 vm_object_reference(object); 406 vm_map_lock(map); 407 rv = vm_map_insert(map, object, offset, start, end, 408 prot, VM_PROT_ALL, cow); 409 vm_map_unlock(map); 410 if (rv != KERN_SUCCESS) 411 vm_object_deallocate(object); 412 } 413 return (rv); 414 } else { 415 return (KERN_SUCCESS); 416 } 417 } 418 419 static int 420 __elfN(load_section)(struct vmspace *vmspace, 421 vm_object_t object, vm_offset_t offset, 422 caddr_t vmaddr, size_t memsz, size_t filsz, vm_prot_t prot, 423 size_t pagesize) 424 { 425 struct sf_buf *sf; 426 size_t map_len; 427 vm_offset_t map_addr; 428 int error, rv, cow; 429 size_t copy_len; 430 vm_offset_t file_addr; 431 432 /* 433 * It's necessary to fail if the filsz + offset taken from the 434 * header is greater than the actual file pager object's size. 435 * If we were to allow this, then the vm_map_find() below would 436 * walk right off the end of the file object and into the ether. 437 * 438 * While I'm here, might as well check for something else that 439 * is invalid: filsz cannot be greater than memsz. 440 */ 441 if ((off_t)filsz + offset > object->un_pager.vnp.vnp_size || 442 filsz > memsz) { 443 uprintf("elf_load_section: truncated ELF file\n"); 444 return (ENOEXEC); 445 } 446 447 map_addr = trunc_page_ps((vm_offset_t)vmaddr, pagesize); 448 file_addr = trunc_page_ps(offset, pagesize); 449 450 /* 451 * We have two choices. We can either clear the data in the last page 452 * of an oversized mapping, or we can start the anon mapping a page 453 * early and copy the initialized data into that first page. We 454 * choose the second.. 455 */ 456 if (memsz > filsz) 457 map_len = trunc_page_ps(offset + filsz, pagesize) - file_addr; 458 else 459 map_len = round_page_ps(offset + filsz, pagesize) - file_addr; 460 461 if (map_len != 0) { 462 /* cow flags: don't dump readonly sections in core */ 463 cow = MAP_COPY_ON_WRITE | MAP_PREFAULT | 464 (prot & VM_PROT_WRITE ? 0 : MAP_DISABLE_COREDUMP); 465 466 rv = __elfN(map_insert)(&vmspace->vm_map, 467 object, 468 file_addr, /* file offset */ 469 map_addr, /* virtual start */ 470 map_addr + map_len,/* virtual end */ 471 prot, 472 cow); 473 if (rv != KERN_SUCCESS) 474 return (EINVAL); 475 476 /* we can stop now if we've covered it all */ 477 if (memsz == filsz) { 478 return (0); 479 } 480 } 481 482 483 /* 484 * We have to get the remaining bit of the file into the first part 485 * of the oversized map segment. This is normally because the .data 486 * segment in the file is extended to provide bss. It's a neat idea 487 * to try and save a page, but it's a pain in the behind to implement. 488 */ 489 copy_len = (offset + filsz) - trunc_page_ps(offset + filsz, pagesize); 490 map_addr = trunc_page_ps((vm_offset_t)vmaddr + filsz, pagesize); 491 map_len = round_page_ps((vm_offset_t)vmaddr + memsz, pagesize) - 492 map_addr; 493 494 /* This had damn well better be true! */ 495 if (map_len != 0) { 496 rv = __elfN(map_insert)(&vmspace->vm_map, NULL, 0, map_addr, 497 map_addr + map_len, VM_PROT_ALL, 0); 498 if (rv != KERN_SUCCESS) { 499 return (EINVAL); 500 } 501 } 502 503 if (copy_len != 0) { 504 vm_offset_t off; 505 506 sf = vm_imgact_map_page(object, offset + filsz); 507 if (sf == NULL) 508 return (EIO); 509 510 /* send the page fragment to user space */ 511 off = trunc_page_ps(offset + filsz, pagesize) - 512 trunc_page(offset + filsz); 513 error = copyout((caddr_t)sf_buf_kva(sf) + off, 514 (caddr_t)map_addr, copy_len); 515 vm_imgact_unmap_page(sf); 516 if (error) { 517 return (error); 518 } 519 } 520 521 /* 522 * set it to the specified protection. 523 * XXX had better undo the damage from pasting over the cracks here! 524 */ 525 vm_map_protect(&vmspace->vm_map, trunc_page(map_addr), 526 round_page(map_addr + map_len), prot, FALSE); 527 528 return (0); 529 } 530 531 /* 532 * Load the file "file" into memory. It may be either a shared object 533 * or an executable. 534 * 535 * The "addr" reference parameter is in/out. On entry, it specifies 536 * the address where a shared object should be loaded. If the file is 537 * an executable, this value is ignored. On exit, "addr" specifies 538 * where the file was actually loaded. 539 * 540 * The "entry" reference parameter is out only. On exit, it specifies 541 * the entry point for the loaded file. 542 */ 543 static int 544 __elfN(load_file)(struct proc *p, const char *file, u_long *addr, 545 u_long *entry, size_t pagesize) 546 { 547 struct { 548 struct nameidata nd; 549 struct vattr attr; 550 struct image_params image_params; 551 } *tempdata; 552 const Elf_Ehdr *hdr = NULL; 553 const Elf_Phdr *phdr = NULL; 554 struct nameidata *nd; 555 struct vmspace *vmspace = p->p_vmspace; 556 struct vattr *attr; 557 struct image_params *imgp; 558 vm_prot_t prot; 559 u_long rbase; 560 u_long base_addr = 0; 561 int vfslocked, error, i, numsegs; 562 563 tempdata = malloc(sizeof(*tempdata), M_TEMP, M_WAITOK); 564 nd = &tempdata->nd; 565 attr = &tempdata->attr; 566 imgp = &tempdata->image_params; 567 568 /* 569 * Initialize part of the common data 570 */ 571 imgp->proc = p; 572 imgp->attr = attr; 573 imgp->firstpage = NULL; 574 imgp->image_header = NULL; 575 imgp->object = NULL; 576 imgp->execlabel = NULL; 577 578 NDINIT(nd, LOOKUP, MPSAFE|LOCKLEAF|FOLLOW, UIO_SYSSPACE, file, 579 curthread); 580 vfslocked = 0; 581 if ((error = namei(nd)) != 0) { 582 nd->ni_vp = NULL; 583 goto fail; 584 } 585 vfslocked = NDHASGIANT(nd); 586 NDFREE(nd, NDF_ONLY_PNBUF); 587 imgp->vp = nd->ni_vp; 588 589 /* 590 * Check permissions, modes, uid, etc on the file, and "open" it. 591 */ 592 error = exec_check_permissions(imgp); 593 if (error) 594 goto fail; 595 596 error = exec_map_first_page(imgp); 597 if (error) 598 goto fail; 599 600 /* 601 * Also make certain that the interpreter stays the same, so set 602 * its VV_TEXT flag, too. 603 */ 604 nd->ni_vp->v_vflag |= VV_TEXT; 605 606 imgp->object = nd->ni_vp->v_object; 607 608 hdr = (const Elf_Ehdr *)imgp->image_header; 609 if ((error = __elfN(check_header)(hdr)) != 0) 610 goto fail; 611 if (hdr->e_type == ET_DYN) 612 rbase = *addr; 613 else if (hdr->e_type == ET_EXEC) 614 rbase = 0; 615 else { 616 error = ENOEXEC; 617 goto fail; 618 } 619 620 /* Only support headers that fit within first page for now */ 621 /* (multiplication of two Elf_Half fields will not overflow) */ 622 if ((hdr->e_phoff > PAGE_SIZE) || 623 (hdr->e_phentsize * hdr->e_phnum) > PAGE_SIZE - hdr->e_phoff) { 624 error = ENOEXEC; 625 goto fail; 626 } 627 628 phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff); 629 if (!aligned(phdr, Elf_Addr)) { 630 error = ENOEXEC; 631 goto fail; 632 } 633 634 for (i = 0, numsegs = 0; i < hdr->e_phnum; i++) { 635 if (phdr[i].p_type == PT_LOAD && phdr[i].p_memsz != 0) { 636 /* Loadable segment */ 637 prot = __elfN(trans_prot)(phdr[i].p_flags); 638 if ((error = __elfN(load_section)(vmspace, 639 imgp->object, phdr[i].p_offset, 640 (caddr_t)(uintptr_t)phdr[i].p_vaddr + rbase, 641 phdr[i].p_memsz, phdr[i].p_filesz, prot, 642 pagesize)) != 0) 643 goto fail; 644 /* 645 * Establish the base address if this is the 646 * first segment. 647 */ 648 if (numsegs == 0) 649 base_addr = trunc_page(phdr[i].p_vaddr + 650 rbase); 651 numsegs++; 652 } 653 } 654 *addr = base_addr; 655 *entry = (unsigned long)hdr->e_entry + rbase; 656 657 fail: 658 if (imgp->firstpage) 659 exec_unmap_first_page(imgp); 660 661 if (nd->ni_vp) 662 vput(nd->ni_vp); 663 664 VFS_UNLOCK_GIANT(vfslocked); 665 free(tempdata, M_TEMP); 666 667 return (error); 668 } 669 670 static int 671 __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp) 672 { 673 const Elf_Ehdr *hdr = (const Elf_Ehdr *)imgp->image_header; 674 const Elf_Phdr *phdr; 675 Elf_Auxargs *elf_auxargs; 676 struct vmspace *vmspace; 677 vm_prot_t prot; 678 u_long text_size = 0, data_size = 0, total_size = 0; 679 u_long text_addr = 0, data_addr = 0; 680 u_long seg_size, seg_addr; 681 u_long addr, baddr, et_dyn_addr, entry = 0, proghdr = 0; 682 int32_t osrel = 0; 683 int error = 0, i, n; 684 const char *interp = NULL, *newinterp = NULL; 685 Elf_Brandinfo *brand_info; 686 char *path; 687 struct sysentvec *sv; 688 689 /* 690 * Do we have a valid ELF header ? 691 * 692 * Only allow ET_EXEC & ET_DYN here, reject ET_DYN later 693 * if particular brand doesn't support it. 694 */ 695 if (__elfN(check_header)(hdr) != 0 || 696 (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN)) 697 return (-1); 698 699 /* 700 * From here on down, we return an errno, not -1, as we've 701 * detected an ELF file. 702 */ 703 704 if ((hdr->e_phoff > PAGE_SIZE) || 705 (hdr->e_phoff + hdr->e_phentsize * hdr->e_phnum) > PAGE_SIZE) { 706 /* Only support headers in first page for now */ 707 return (ENOEXEC); 708 } 709 phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff); 710 if (!aligned(phdr, Elf_Addr)) 711 return (ENOEXEC); 712 n = 0; 713 baddr = 0; 714 for (i = 0; i < hdr->e_phnum; i++) { 715 if (phdr[i].p_type == PT_LOAD) { 716 if (n == 0) 717 baddr = phdr[i].p_vaddr; 718 n++; 719 continue; 720 } 721 if (phdr[i].p_type == PT_INTERP) { 722 /* Path to interpreter */ 723 if (phdr[i].p_filesz > MAXPATHLEN || 724 phdr[i].p_offset + phdr[i].p_filesz > PAGE_SIZE) 725 return (ENOEXEC); 726 interp = imgp->image_header + phdr[i].p_offset; 727 continue; 728 } 729 } 730 731 brand_info = __elfN(get_brandinfo)(imgp, interp, &osrel); 732 if (brand_info == NULL) { 733 uprintf("ELF binary type \"%u\" not known.\n", 734 hdr->e_ident[EI_OSABI]); 735 return (ENOEXEC); 736 } 737 if (hdr->e_type == ET_DYN) { 738 if ((brand_info->flags & BI_CAN_EXEC_DYN) == 0) 739 return (ENOEXEC); 740 /* 741 * Honour the base load address from the dso if it is 742 * non-zero for some reason. 743 */ 744 if (baddr == 0) 745 et_dyn_addr = ET_DYN_LOAD_ADDR; 746 else 747 et_dyn_addr = 0; 748 } else 749 et_dyn_addr = 0; 750 sv = brand_info->sysvec; 751 if (interp != NULL && brand_info->interp_newpath != NULL) 752 newinterp = brand_info->interp_newpath; 753 754 /* 755 * Avoid a possible deadlock if the current address space is destroyed 756 * and that address space maps the locked vnode. In the common case, 757 * the locked vnode's v_usecount is decremented but remains greater 758 * than zero. Consequently, the vnode lock is not needed by vrele(). 759 * However, in cases where the vnode lock is external, such as nullfs, 760 * v_usecount may become zero. 761 */ 762 VOP_UNLOCK(imgp->vp, 0); 763 764 error = exec_new_vmspace(imgp, sv); 765 imgp->proc->p_sysent = sv; 766 767 vn_lock(imgp->vp, LK_EXCLUSIVE | LK_RETRY); 768 if (error) 769 return (error); 770 771 vmspace = imgp->proc->p_vmspace; 772 773 for (i = 0; i < hdr->e_phnum; i++) { 774 switch (phdr[i].p_type) { 775 case PT_LOAD: /* Loadable segment */ 776 if (phdr[i].p_memsz == 0) 777 break; 778 prot = __elfN(trans_prot)(phdr[i].p_flags); 779 780 #if defined(__ia64__) && __ELF_WORD_SIZE == 32 && defined(IA32_ME_HARDER) 781 /* 782 * Some x86 binaries assume read == executable, 783 * notably the M3 runtime and therefore cvsup 784 */ 785 if (prot & VM_PROT_READ) 786 prot |= VM_PROT_EXECUTE; 787 #endif 788 789 if ((error = __elfN(load_section)(vmspace, 790 imgp->object, phdr[i].p_offset, 791 (caddr_t)(uintptr_t)phdr[i].p_vaddr + et_dyn_addr, 792 phdr[i].p_memsz, phdr[i].p_filesz, prot, 793 sv->sv_pagesize)) != 0) 794 return (error); 795 796 /* 797 * If this segment contains the program headers, 798 * remember their virtual address for the AT_PHDR 799 * aux entry. Static binaries don't usually include 800 * a PT_PHDR entry. 801 */ 802 if (phdr[i].p_offset == 0 && 803 hdr->e_phoff + hdr->e_phnum * hdr->e_phentsize 804 <= phdr[i].p_filesz) 805 proghdr = phdr[i].p_vaddr + hdr->e_phoff + 806 et_dyn_addr; 807 808 seg_addr = trunc_page(phdr[i].p_vaddr + et_dyn_addr); 809 seg_size = round_page(phdr[i].p_memsz + 810 phdr[i].p_vaddr + et_dyn_addr - seg_addr); 811 812 /* 813 * Is this .text or .data? We can't use 814 * VM_PROT_WRITE or VM_PROT_EXEC, it breaks the 815 * alpha terribly and possibly does other bad 816 * things so we stick to the old way of figuring 817 * it out: If the segment contains the program 818 * entry point, it's a text segment, otherwise it 819 * is a data segment. 820 * 821 * Note that obreak() assumes that data_addr + 822 * data_size == end of data load area, and the ELF 823 * file format expects segments to be sorted by 824 * address. If multiple data segments exist, the 825 * last one will be used. 826 */ 827 if (hdr->e_entry >= phdr[i].p_vaddr && 828 hdr->e_entry < (phdr[i].p_vaddr + 829 phdr[i].p_memsz)) { 830 text_size = seg_size; 831 text_addr = seg_addr; 832 entry = (u_long)hdr->e_entry + et_dyn_addr; 833 } else { 834 data_size = seg_size; 835 data_addr = seg_addr; 836 } 837 total_size += seg_size; 838 break; 839 case PT_PHDR: /* Program header table info */ 840 proghdr = phdr[i].p_vaddr + et_dyn_addr; 841 break; 842 default: 843 break; 844 } 845 } 846 847 if (data_addr == 0 && data_size == 0) { 848 data_addr = text_addr; 849 data_size = text_size; 850 } 851 852 /* 853 * Check limits. It should be safe to check the 854 * limits after loading the segments since we do 855 * not actually fault in all the segments pages. 856 */ 857 PROC_LOCK(imgp->proc); 858 if (data_size > lim_cur(imgp->proc, RLIMIT_DATA) || 859 text_size > maxtsiz || 860 total_size > lim_cur(imgp->proc, RLIMIT_VMEM)) { 861 PROC_UNLOCK(imgp->proc); 862 return (ENOMEM); 863 } 864 865 vmspace->vm_tsize = text_size >> PAGE_SHIFT; 866 vmspace->vm_taddr = (caddr_t)(uintptr_t)text_addr; 867 vmspace->vm_dsize = data_size >> PAGE_SHIFT; 868 vmspace->vm_daddr = (caddr_t)(uintptr_t)data_addr; 869 870 /* 871 * We load the dynamic linker where a userland call 872 * to mmap(0, ...) would put it. The rationale behind this 873 * calculation is that it leaves room for the heap to grow to 874 * its maximum allowed size. 875 */ 876 addr = round_page((vm_offset_t)imgp->proc->p_vmspace->vm_daddr + 877 lim_max(imgp->proc, RLIMIT_DATA)); 878 PROC_UNLOCK(imgp->proc); 879 880 imgp->entry_addr = entry; 881 882 if (interp != NULL) { 883 int have_interp = FALSE; 884 VOP_UNLOCK(imgp->vp, 0); 885 if (brand_info->emul_path != NULL && 886 brand_info->emul_path[0] != '\0') { 887 path = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 888 snprintf(path, MAXPATHLEN, "%s%s", 889 brand_info->emul_path, interp); 890 error = __elfN(load_file)(imgp->proc, path, &addr, 891 &imgp->entry_addr, sv->sv_pagesize); 892 free(path, M_TEMP); 893 if (error == 0) 894 have_interp = TRUE; 895 } 896 if (!have_interp && newinterp != NULL) { 897 error = __elfN(load_file)(imgp->proc, newinterp, &addr, 898 &imgp->entry_addr, sv->sv_pagesize); 899 if (error == 0) 900 have_interp = TRUE; 901 } 902 if (!have_interp) { 903 error = __elfN(load_file)(imgp->proc, interp, &addr, 904 &imgp->entry_addr, sv->sv_pagesize); 905 } 906 vn_lock(imgp->vp, LK_EXCLUSIVE | LK_RETRY); 907 if (error != 0) { 908 uprintf("ELF interpreter %s not found\n", interp); 909 return (error); 910 } 911 } else 912 addr = et_dyn_addr; 913 914 /* 915 * Construct auxargs table (used by the fixup routine) 916 */ 917 elf_auxargs = malloc(sizeof(Elf_Auxargs), M_TEMP, M_WAITOK); 918 elf_auxargs->execfd = -1; 919 elf_auxargs->phdr = proghdr; 920 elf_auxargs->phent = hdr->e_phentsize; 921 elf_auxargs->phnum = hdr->e_phnum; 922 elf_auxargs->pagesz = PAGE_SIZE; 923 elf_auxargs->base = addr; 924 elf_auxargs->flags = 0; 925 elf_auxargs->entry = entry; 926 927 imgp->auxargs = elf_auxargs; 928 imgp->interpreted = 0; 929 imgp->proc->p_osrel = osrel; 930 931 return (error); 932 } 933 934 #define suword __CONCAT(suword, __ELF_WORD_SIZE) 935 936 int 937 __elfN(freebsd_fixup)(register_t **stack_base, struct image_params *imgp) 938 { 939 Elf_Auxargs *args = (Elf_Auxargs *)imgp->auxargs; 940 Elf_Addr *base; 941 Elf_Addr *pos; 942 943 base = (Elf_Addr *)*stack_base; 944 pos = base + (imgp->args->argc + imgp->args->envc + 2); 945 946 if (args->execfd != -1) 947 AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd); 948 AUXARGS_ENTRY(pos, AT_PHDR, args->phdr); 949 AUXARGS_ENTRY(pos, AT_PHENT, args->phent); 950 AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum); 951 AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz); 952 AUXARGS_ENTRY(pos, AT_FLAGS, args->flags); 953 AUXARGS_ENTRY(pos, AT_ENTRY, args->entry); 954 AUXARGS_ENTRY(pos, AT_BASE, args->base); 955 if (imgp->execpathp != 0) 956 AUXARGS_ENTRY(pos, AT_EXECPATH, imgp->execpathp); 957 AUXARGS_ENTRY(pos, AT_NULL, 0); 958 959 free(imgp->auxargs, M_TEMP); 960 imgp->auxargs = NULL; 961 962 base--; 963 suword(base, (long)imgp->args->argc); 964 *stack_base = (register_t *)base; 965 return (0); 966 } 967 968 /* 969 * Code for generating ELF core dumps. 970 */ 971 972 typedef void (*segment_callback)(vm_map_entry_t, void *); 973 974 /* Closure for cb_put_phdr(). */ 975 struct phdr_closure { 976 Elf_Phdr *phdr; /* Program header to fill in */ 977 Elf_Off offset; /* Offset of segment in core file */ 978 }; 979 980 /* Closure for cb_size_segment(). */ 981 struct sseg_closure { 982 int count; /* Count of writable segments. */ 983 size_t size; /* Total size of all writable segments. */ 984 }; 985 986 static void cb_put_phdr(vm_map_entry_t, void *); 987 static void cb_size_segment(vm_map_entry_t, void *); 988 static void each_writable_segment(struct thread *, segment_callback, void *); 989 static int __elfN(corehdr)(struct thread *, struct vnode *, struct ucred *, 990 int, void *, size_t); 991 static void __elfN(puthdr)(struct thread *, void *, size_t *, int); 992 static void __elfN(putnote)(void *, size_t *, const char *, int, 993 const void *, size_t); 994 995 int 996 __elfN(coredump)(td, vp, limit) 997 struct thread *td; 998 struct vnode *vp; 999 off_t limit; 1000 { 1001 struct ucred *cred = td->td_ucred; 1002 int error = 0; 1003 struct sseg_closure seginfo; 1004 void *hdr; 1005 size_t hdrsize; 1006 1007 /* Size the program segments. */ 1008 seginfo.count = 0; 1009 seginfo.size = 0; 1010 each_writable_segment(td, cb_size_segment, &seginfo); 1011 1012 /* 1013 * Calculate the size of the core file header area by making 1014 * a dry run of generating it. Nothing is written, but the 1015 * size is calculated. 1016 */ 1017 hdrsize = 0; 1018 __elfN(puthdr)(td, (void *)NULL, &hdrsize, seginfo.count); 1019 1020 if (hdrsize + seginfo.size >= limit) 1021 return (EFAULT); 1022 1023 /* 1024 * Allocate memory for building the header, fill it up, 1025 * and write it out. 1026 */ 1027 hdr = malloc(hdrsize, M_TEMP, M_WAITOK); 1028 if (hdr == NULL) { 1029 return (EINVAL); 1030 } 1031 error = __elfN(corehdr)(td, vp, cred, seginfo.count, hdr, hdrsize); 1032 1033 /* Write the contents of all of the writable segments. */ 1034 if (error == 0) { 1035 Elf_Phdr *php; 1036 off_t offset; 1037 int i; 1038 1039 php = (Elf_Phdr *)((char *)hdr + sizeof(Elf_Ehdr)) + 1; 1040 offset = hdrsize; 1041 for (i = 0; i < seginfo.count; i++) { 1042 error = vn_rdwr_inchunks(UIO_WRITE, vp, 1043 (caddr_t)(uintptr_t)php->p_vaddr, 1044 php->p_filesz, offset, UIO_USERSPACE, 1045 IO_UNIT | IO_DIRECT, cred, NOCRED, NULL, 1046 curthread); 1047 if (error != 0) 1048 break; 1049 offset += php->p_filesz; 1050 php++; 1051 } 1052 } 1053 free(hdr, M_TEMP); 1054 1055 return (error); 1056 } 1057 1058 /* 1059 * A callback for each_writable_segment() to write out the segment's 1060 * program header entry. 1061 */ 1062 static void 1063 cb_put_phdr(entry, closure) 1064 vm_map_entry_t entry; 1065 void *closure; 1066 { 1067 struct phdr_closure *phc = (struct phdr_closure *)closure; 1068 Elf_Phdr *phdr = phc->phdr; 1069 1070 phc->offset = round_page(phc->offset); 1071 1072 phdr->p_type = PT_LOAD; 1073 phdr->p_offset = phc->offset; 1074 phdr->p_vaddr = entry->start; 1075 phdr->p_paddr = 0; 1076 phdr->p_filesz = phdr->p_memsz = entry->end - entry->start; 1077 phdr->p_align = PAGE_SIZE; 1078 phdr->p_flags = __elfN(untrans_prot)(entry->protection); 1079 1080 phc->offset += phdr->p_filesz; 1081 phc->phdr++; 1082 } 1083 1084 /* 1085 * A callback for each_writable_segment() to gather information about 1086 * the number of segments and their total size. 1087 */ 1088 static void 1089 cb_size_segment(entry, closure) 1090 vm_map_entry_t entry; 1091 void *closure; 1092 { 1093 struct sseg_closure *ssc = (struct sseg_closure *)closure; 1094 1095 ssc->count++; 1096 ssc->size += entry->end - entry->start; 1097 } 1098 1099 /* 1100 * For each writable segment in the process's memory map, call the given 1101 * function with a pointer to the map entry and some arbitrary 1102 * caller-supplied data. 1103 */ 1104 static void 1105 each_writable_segment(td, func, closure) 1106 struct thread *td; 1107 segment_callback func; 1108 void *closure; 1109 { 1110 struct proc *p = td->td_proc; 1111 vm_map_t map = &p->p_vmspace->vm_map; 1112 vm_map_entry_t entry; 1113 vm_object_t backing_object, object; 1114 boolean_t ignore_entry; 1115 1116 vm_map_lock_read(map); 1117 for (entry = map->header.next; entry != &map->header; 1118 entry = entry->next) { 1119 /* 1120 * Don't dump inaccessible mappings, deal with legacy 1121 * coredump mode. 1122 * 1123 * Note that read-only segments related to the elf binary 1124 * are marked MAP_ENTRY_NOCOREDUMP now so we no longer 1125 * need to arbitrarily ignore such segments. 1126 */ 1127 if (elf_legacy_coredump) { 1128 if ((entry->protection & VM_PROT_RW) != VM_PROT_RW) 1129 continue; 1130 } else { 1131 if ((entry->protection & VM_PROT_ALL) == 0) 1132 continue; 1133 } 1134 1135 /* 1136 * Dont include memory segment in the coredump if 1137 * MAP_NOCORE is set in mmap(2) or MADV_NOCORE in 1138 * madvise(2). Do not dump submaps (i.e. parts of the 1139 * kernel map). 1140 */ 1141 if (entry->eflags & (MAP_ENTRY_NOCOREDUMP|MAP_ENTRY_IS_SUB_MAP)) 1142 continue; 1143 1144 if ((object = entry->object.vm_object) == NULL) 1145 continue; 1146 1147 /* Ignore memory-mapped devices and such things. */ 1148 VM_OBJECT_LOCK(object); 1149 while ((backing_object = object->backing_object) != NULL) { 1150 VM_OBJECT_LOCK(backing_object); 1151 VM_OBJECT_UNLOCK(object); 1152 object = backing_object; 1153 } 1154 ignore_entry = object->type != OBJT_DEFAULT && 1155 object->type != OBJT_SWAP && object->type != OBJT_VNODE; 1156 VM_OBJECT_UNLOCK(object); 1157 if (ignore_entry) 1158 continue; 1159 1160 (*func)(entry, closure); 1161 } 1162 vm_map_unlock_read(map); 1163 } 1164 1165 /* 1166 * Write the core file header to the file, including padding up to 1167 * the page boundary. 1168 */ 1169 static int 1170 __elfN(corehdr)(td, vp, cred, numsegs, hdr, hdrsize) 1171 struct thread *td; 1172 struct vnode *vp; 1173 struct ucred *cred; 1174 int numsegs; 1175 size_t hdrsize; 1176 void *hdr; 1177 { 1178 size_t off; 1179 1180 /* Fill in the header. */ 1181 bzero(hdr, hdrsize); 1182 off = 0; 1183 __elfN(puthdr)(td, hdr, &off, numsegs); 1184 1185 /* Write it to the core file. */ 1186 return (vn_rdwr_inchunks(UIO_WRITE, vp, hdr, hdrsize, (off_t)0, 1187 UIO_SYSSPACE, IO_UNIT | IO_DIRECT, cred, NOCRED, NULL, 1188 td)); 1189 } 1190 1191 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32 1192 #include <compat/freebsd32/freebsd32.h> 1193 1194 typedef struct prstatus32 elf_prstatus_t; 1195 typedef struct prpsinfo32 elf_prpsinfo_t; 1196 typedef struct fpreg32 elf_prfpregset_t; 1197 typedef struct fpreg32 elf_fpregset_t; 1198 typedef struct reg32 elf_gregset_t; 1199 typedef struct thrmisc32 elf_thrmisc_t; 1200 #else 1201 typedef prstatus_t elf_prstatus_t; 1202 typedef prpsinfo_t elf_prpsinfo_t; 1203 typedef prfpregset_t elf_prfpregset_t; 1204 typedef prfpregset_t elf_fpregset_t; 1205 typedef gregset_t elf_gregset_t; 1206 typedef thrmisc_t elf_thrmisc_t; 1207 #endif 1208 1209 static void 1210 __elfN(puthdr)(struct thread *td, void *dst, size_t *off, int numsegs) 1211 { 1212 struct { 1213 elf_prstatus_t status; 1214 elf_prfpregset_t fpregset; 1215 elf_prpsinfo_t psinfo; 1216 elf_thrmisc_t thrmisc; 1217 } *tempdata; 1218 elf_prstatus_t *status; 1219 elf_prfpregset_t *fpregset; 1220 elf_prpsinfo_t *psinfo; 1221 elf_thrmisc_t *thrmisc; 1222 struct proc *p; 1223 struct thread *thr; 1224 size_t ehoff, noteoff, notesz, phoff; 1225 1226 p = td->td_proc; 1227 1228 ehoff = *off; 1229 *off += sizeof(Elf_Ehdr); 1230 1231 phoff = *off; 1232 *off += (numsegs + 1) * sizeof(Elf_Phdr); 1233 1234 noteoff = *off; 1235 /* 1236 * Don't allocate space for the notes if we're just calculating 1237 * the size of the header. We also don't collect the data. 1238 */ 1239 if (dst != NULL) { 1240 tempdata = malloc(sizeof(*tempdata), M_TEMP, M_ZERO|M_WAITOK); 1241 status = &tempdata->status; 1242 fpregset = &tempdata->fpregset; 1243 psinfo = &tempdata->psinfo; 1244 thrmisc = &tempdata->thrmisc; 1245 } else { 1246 tempdata = NULL; 1247 status = NULL; 1248 fpregset = NULL; 1249 psinfo = NULL; 1250 thrmisc = NULL; 1251 } 1252 1253 if (dst != NULL) { 1254 psinfo->pr_version = PRPSINFO_VERSION; 1255 psinfo->pr_psinfosz = sizeof(elf_prpsinfo_t); 1256 strlcpy(psinfo->pr_fname, p->p_comm, sizeof(psinfo->pr_fname)); 1257 /* 1258 * XXX - We don't fill in the command line arguments properly 1259 * yet. 1260 */ 1261 strlcpy(psinfo->pr_psargs, p->p_comm, 1262 sizeof(psinfo->pr_psargs)); 1263 } 1264 __elfN(putnote)(dst, off, "FreeBSD", NT_PRPSINFO, psinfo, 1265 sizeof *psinfo); 1266 1267 /* 1268 * To have the debugger select the right thread (LWP) as the initial 1269 * thread, we dump the state of the thread passed to us in td first. 1270 * This is the thread that causes the core dump and thus likely to 1271 * be the right thread one wants to have selected in the debugger. 1272 */ 1273 thr = td; 1274 while (thr != NULL) { 1275 if (dst != NULL) { 1276 status->pr_version = PRSTATUS_VERSION; 1277 status->pr_statussz = sizeof(elf_prstatus_t); 1278 status->pr_gregsetsz = sizeof(elf_gregset_t); 1279 status->pr_fpregsetsz = sizeof(elf_fpregset_t); 1280 status->pr_osreldate = osreldate; 1281 status->pr_cursig = p->p_sig; 1282 status->pr_pid = thr->td_tid; 1283 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32 1284 fill_regs32(thr, &status->pr_reg); 1285 fill_fpregs32(thr, fpregset); 1286 #else 1287 fill_regs(thr, &status->pr_reg); 1288 fill_fpregs(thr, fpregset); 1289 #endif 1290 memset(&thrmisc->_pad, 0, sizeof (thrmisc->_pad)); 1291 strcpy(thrmisc->pr_tname, thr->td_name); 1292 } 1293 __elfN(putnote)(dst, off, "FreeBSD", NT_PRSTATUS, status, 1294 sizeof *status); 1295 __elfN(putnote)(dst, off, "FreeBSD", NT_FPREGSET, fpregset, 1296 sizeof *fpregset); 1297 __elfN(putnote)(dst, off, "FreeBSD", NT_THRMISC, thrmisc, 1298 sizeof *thrmisc); 1299 /* 1300 * Allow for MD specific notes, as well as any MD 1301 * specific preparations for writing MI notes. 1302 */ 1303 __elfN(dump_thread)(thr, dst, off); 1304 1305 thr = (thr == td) ? TAILQ_FIRST(&p->p_threads) : 1306 TAILQ_NEXT(thr, td_plist); 1307 if (thr == td) 1308 thr = TAILQ_NEXT(thr, td_plist); 1309 } 1310 1311 notesz = *off - noteoff; 1312 1313 if (dst != NULL) 1314 free(tempdata, M_TEMP); 1315 1316 /* Align up to a page boundary for the program segments. */ 1317 *off = round_page(*off); 1318 1319 if (dst != NULL) { 1320 Elf_Ehdr *ehdr; 1321 Elf_Phdr *phdr; 1322 struct phdr_closure phc; 1323 1324 /* 1325 * Fill in the ELF header. 1326 */ 1327 ehdr = (Elf_Ehdr *)((char *)dst + ehoff); 1328 ehdr->e_ident[EI_MAG0] = ELFMAG0; 1329 ehdr->e_ident[EI_MAG1] = ELFMAG1; 1330 ehdr->e_ident[EI_MAG2] = ELFMAG2; 1331 ehdr->e_ident[EI_MAG3] = ELFMAG3; 1332 ehdr->e_ident[EI_CLASS] = ELF_CLASS; 1333 ehdr->e_ident[EI_DATA] = ELF_DATA; 1334 ehdr->e_ident[EI_VERSION] = EV_CURRENT; 1335 ehdr->e_ident[EI_OSABI] = ELFOSABI_FREEBSD; 1336 ehdr->e_ident[EI_ABIVERSION] = 0; 1337 ehdr->e_ident[EI_PAD] = 0; 1338 ehdr->e_type = ET_CORE; 1339 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32 1340 ehdr->e_machine = ELF_ARCH32; 1341 #else 1342 ehdr->e_machine = ELF_ARCH; 1343 #endif 1344 ehdr->e_version = EV_CURRENT; 1345 ehdr->e_entry = 0; 1346 ehdr->e_phoff = phoff; 1347 ehdr->e_flags = 0; 1348 ehdr->e_ehsize = sizeof(Elf_Ehdr); 1349 ehdr->e_phentsize = sizeof(Elf_Phdr); 1350 ehdr->e_phnum = numsegs + 1; 1351 ehdr->e_shentsize = sizeof(Elf_Shdr); 1352 ehdr->e_shnum = 0; 1353 ehdr->e_shstrndx = SHN_UNDEF; 1354 1355 /* 1356 * Fill in the program header entries. 1357 */ 1358 phdr = (Elf_Phdr *)((char *)dst + phoff); 1359 1360 /* The note segement. */ 1361 phdr->p_type = PT_NOTE; 1362 phdr->p_offset = noteoff; 1363 phdr->p_vaddr = 0; 1364 phdr->p_paddr = 0; 1365 phdr->p_filesz = notesz; 1366 phdr->p_memsz = 0; 1367 phdr->p_flags = 0; 1368 phdr->p_align = 0; 1369 phdr++; 1370 1371 /* All the writable segments from the program. */ 1372 phc.phdr = phdr; 1373 phc.offset = *off; 1374 each_writable_segment(td, cb_put_phdr, &phc); 1375 } 1376 } 1377 1378 static void 1379 __elfN(putnote)(void *dst, size_t *off, const char *name, int type, 1380 const void *desc, size_t descsz) 1381 { 1382 Elf_Note note; 1383 1384 note.n_namesz = strlen(name) + 1; 1385 note.n_descsz = descsz; 1386 note.n_type = type; 1387 if (dst != NULL) 1388 bcopy(¬e, (char *)dst + *off, sizeof note); 1389 *off += sizeof note; 1390 if (dst != NULL) 1391 bcopy(name, (char *)dst + *off, note.n_namesz); 1392 *off += roundup2(note.n_namesz, sizeof(Elf_Size)); 1393 if (dst != NULL) 1394 bcopy(desc, (char *)dst + *off, note.n_descsz); 1395 *off += roundup2(note.n_descsz, sizeof(Elf_Size)); 1396 } 1397 1398 /* 1399 * Try to find the appropriate ABI-note section for checknote, 1400 * fetch the osreldate for binary from the ELF OSABI-note. Only the 1401 * first page of the image is searched, the same as for headers. 1402 */ 1403 static boolean_t 1404 __elfN(check_note)(struct image_params *imgp, Elf_Brandnote *checknote, 1405 int32_t *osrel) 1406 { 1407 const Elf_Note *note, *note0, *note_end; 1408 const Elf_Phdr *phdr, *pnote; 1409 const Elf_Ehdr *hdr; 1410 const char *note_name; 1411 int i; 1412 1413 pnote = NULL; 1414 hdr = (const Elf_Ehdr *)imgp->image_header; 1415 phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff); 1416 1417 for (i = 0; i < hdr->e_phnum; i++) { 1418 if (phdr[i].p_type == PT_NOTE) { 1419 pnote = &phdr[i]; 1420 break; 1421 } 1422 } 1423 1424 if (pnote == NULL || pnote->p_offset >= PAGE_SIZE || 1425 pnote->p_offset + pnote->p_filesz >= PAGE_SIZE) 1426 return (FALSE); 1427 1428 note = note0 = (const Elf_Note *)(imgp->image_header + pnote->p_offset); 1429 note_end = (const Elf_Note *)(imgp->image_header + 1430 pnote->p_offset + pnote->p_filesz); 1431 for (i = 0; i < 100 && note >= note0 && note < note_end; i++) { 1432 if (!aligned(note, Elf32_Addr)) 1433 return (FALSE); 1434 if (note->n_namesz != checknote->hdr.n_namesz || 1435 note->n_descsz != checknote->hdr.n_descsz || 1436 note->n_type != checknote->hdr.n_type) 1437 goto nextnote; 1438 note_name = (const char *)(note + 1); 1439 if (strncmp(checknote->vendor, note_name, 1440 checknote->hdr.n_namesz) != 0) 1441 goto nextnote; 1442 1443 /* 1444 * Fetch the osreldate for binary 1445 * from the ELF OSABI-note if necessary. 1446 */ 1447 if ((checknote->flags & BN_TRANSLATE_OSREL) != 0 && 1448 checknote->trans_osrel != NULL) 1449 return (checknote->trans_osrel(note, osrel)); 1450 return (TRUE); 1451 1452 nextnote: 1453 note = (const Elf_Note *)((const char *)(note + 1) + 1454 roundup2(note->n_namesz, sizeof(Elf32_Addr)) + 1455 roundup2(note->n_descsz, sizeof(Elf32_Addr))); 1456 } 1457 1458 return (FALSE); 1459 } 1460 1461 /* 1462 * Tell kern_execve.c about it, with a little help from the linker. 1463 */ 1464 static struct execsw __elfN(execsw) = { 1465 __CONCAT(exec_, __elfN(imgact)), 1466 __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) 1467 }; 1468 EXEC_SET(__CONCAT(elf, __ELF_WORD_SIZE), __elfN(execsw)); 1469 1470 static vm_prot_t 1471 __elfN(trans_prot)(Elf_Word flags) 1472 { 1473 vm_prot_t prot; 1474 1475 prot = 0; 1476 if (flags & PF_X) 1477 prot |= VM_PROT_EXECUTE; 1478 if (flags & PF_W) 1479 prot |= VM_PROT_WRITE; 1480 if (flags & PF_R) 1481 prot |= VM_PROT_READ; 1482 return (prot); 1483 } 1484 1485 static Elf_Word 1486 __elfN(untrans_prot)(vm_prot_t prot) 1487 { 1488 Elf_Word flags; 1489 1490 flags = 0; 1491 if (prot & VM_PROT_EXECUTE) 1492 flags |= PF_X; 1493 if (prot & VM_PROT_READ) 1494 flags |= PF_R; 1495 if (prot & VM_PROT_WRITE) 1496 flags |= PF_W; 1497 return (flags); 1498 }
Cache object: c51d8c34470844a87b8af189a9fb1d13
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