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/9.1/sys/kern/imgact_elf.c 238679 2012-07-22 00:44:22Z kib $"); 33 34 #include "opt_capsicum.h" 35 #include "opt_compat.h" 36 #include "opt_core.h" 37 38 #include <sys/param.h> 39 #include <sys/capability.h> 40 #include <sys/exec.h> 41 #include <sys/fcntl.h> 42 #include <sys/imgact.h> 43 #include <sys/imgact_elf.h> 44 #include <sys/kernel.h> 45 #include <sys/lock.h> 46 #include <sys/malloc.h> 47 #include <sys/mount.h> 48 #include <sys/mutex.h> 49 #include <sys/mman.h> 50 #include <sys/namei.h> 51 #include <sys/pioctl.h> 52 #include <sys/proc.h> 53 #include <sys/procfs.h> 54 #include <sys/racct.h> 55 #include <sys/resourcevar.h> 56 #include <sys/sf_buf.h> 57 #include <sys/smp.h> 58 #include <sys/systm.h> 59 #include <sys/signalvar.h> 60 #include <sys/stat.h> 61 #include <sys/sx.h> 62 #include <sys/syscall.h> 63 #include <sys/sysctl.h> 64 #include <sys/sysent.h> 65 #include <sys/vnode.h> 66 #include <sys/syslog.h> 67 #include <sys/eventhandler.h> 68 69 #include <net/zlib.h> 70 71 #include <vm/vm.h> 72 #include <vm/vm_kern.h> 73 #include <vm/vm_param.h> 74 #include <vm/pmap.h> 75 #include <vm/vm_map.h> 76 #include <vm/vm_object.h> 77 #include <vm/vm_extern.h> 78 79 #include <machine/elf.h> 80 #include <machine/md_var.h> 81 82 #define OLD_EI_BRAND 8 83 84 static int __elfN(check_header)(const Elf_Ehdr *hdr); 85 static Elf_Brandinfo *__elfN(get_brandinfo)(struct image_params *imgp, 86 const char *interp, int interp_name_len, int32_t *osrel); 87 static int __elfN(load_file)(struct proc *p, const char *file, u_long *addr, 88 u_long *entry, size_t pagesize); 89 static int __elfN(load_section)(struct vmspace *vmspace, vm_object_t object, 90 vm_offset_t offset, caddr_t vmaddr, size_t memsz, size_t filsz, 91 vm_prot_t prot, size_t pagesize); 92 static int __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp); 93 static boolean_t __elfN(freebsd_trans_osrel)(const Elf_Note *note, 94 int32_t *osrel); 95 static boolean_t kfreebsd_trans_osrel(const Elf_Note *note, int32_t *osrel); 96 static boolean_t __elfN(check_note)(struct image_params *imgp, 97 Elf_Brandnote *checknote, int32_t *osrel); 98 static vm_prot_t __elfN(trans_prot)(Elf_Word); 99 static Elf_Word __elfN(untrans_prot)(vm_prot_t); 100 101 SYSCTL_NODE(_kern, OID_AUTO, __CONCAT(elf, __ELF_WORD_SIZE), CTLFLAG_RW, 0, 102 ""); 103 104 #ifdef COMPRESS_USER_CORES 105 static int compress_core(gzFile, char *, char *, unsigned int, 106 struct thread * td); 107 #define CORE_BUF_SIZE (16 * 1024) 108 #endif 109 110 int __elfN(fallback_brand) = -1; 111 SYSCTL_INT(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO, 112 fallback_brand, CTLFLAG_RW, &__elfN(fallback_brand), 0, 113 __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) " brand of last resort"); 114 TUNABLE_INT("kern.elf" __XSTRING(__ELF_WORD_SIZE) ".fallback_brand", 115 &__elfN(fallback_brand)); 116 117 static int elf_legacy_coredump = 0; 118 SYSCTL_INT(_debug, OID_AUTO, __elfN(legacy_coredump), CTLFLAG_RW, 119 &elf_legacy_coredump, 0, ""); 120 121 int __elfN(nxstack) = 122 #if defined(__amd64__) || defined(__powerpc64__) /* both 64 and 32 bit */ 123 1; 124 #else 125 0; 126 #endif 127 SYSCTL_INT(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO, 128 nxstack, CTLFLAG_RW, &__elfN(nxstack), 0, 129 __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) ": enable non-executable stack"); 130 131 #if __ELF_WORD_SIZE == 32 132 #if defined(__amd64__) || defined(__ia64__) 133 int i386_read_exec = 0; 134 SYSCTL_INT(_kern_elf32, OID_AUTO, read_exec, CTLFLAG_RW, &i386_read_exec, 0, 135 "enable execution from readable segments"); 136 #endif 137 #endif 138 139 static Elf_Brandinfo *elf_brand_list[MAX_BRANDS]; 140 141 #define trunc_page_ps(va, ps) ((va) & ~(ps - 1)) 142 #define round_page_ps(va, ps) (((va) + (ps - 1)) & ~(ps - 1)) 143 #define aligned(a, t) (trunc_page_ps((u_long)(a), sizeof(t)) == (u_long)(a)) 144 145 static const char FREEBSD_ABI_VENDOR[] = "FreeBSD"; 146 147 Elf_Brandnote __elfN(freebsd_brandnote) = { 148 .hdr.n_namesz = sizeof(FREEBSD_ABI_VENDOR), 149 .hdr.n_descsz = sizeof(int32_t), 150 .hdr.n_type = 1, 151 .vendor = FREEBSD_ABI_VENDOR, 152 .flags = BN_TRANSLATE_OSREL, 153 .trans_osrel = __elfN(freebsd_trans_osrel) 154 }; 155 156 static boolean_t 157 __elfN(freebsd_trans_osrel)(const Elf_Note *note, int32_t *osrel) 158 { 159 uintptr_t p; 160 161 p = (uintptr_t)(note + 1); 162 p += roundup2(note->n_namesz, sizeof(Elf32_Addr)); 163 *osrel = *(const int32_t *)(p); 164 165 return (TRUE); 166 } 167 168 static const char GNU_ABI_VENDOR[] = "GNU"; 169 static int GNU_KFREEBSD_ABI_DESC = 3; 170 171 Elf_Brandnote __elfN(kfreebsd_brandnote) = { 172 .hdr.n_namesz = sizeof(GNU_ABI_VENDOR), 173 .hdr.n_descsz = 16, /* XXX at least 16 */ 174 .hdr.n_type = 1, 175 .vendor = GNU_ABI_VENDOR, 176 .flags = BN_TRANSLATE_OSREL, 177 .trans_osrel = kfreebsd_trans_osrel 178 }; 179 180 static boolean_t 181 kfreebsd_trans_osrel(const Elf_Note *note, int32_t *osrel) 182 { 183 const Elf32_Word *desc; 184 uintptr_t p; 185 186 p = (uintptr_t)(note + 1); 187 p += roundup2(note->n_namesz, sizeof(Elf32_Addr)); 188 189 desc = (const Elf32_Word *)p; 190 if (desc[0] != GNU_KFREEBSD_ABI_DESC) 191 return (FALSE); 192 193 /* 194 * Debian GNU/kFreeBSD embed the earliest compatible kernel version 195 * (__FreeBSD_version: <major><two digit minor>Rxx) in the LSB way. 196 */ 197 *osrel = desc[1] * 100000 + desc[2] * 1000 + desc[3]; 198 199 return (TRUE); 200 } 201 202 int 203 __elfN(insert_brand_entry)(Elf_Brandinfo *entry) 204 { 205 int i; 206 207 for (i = 0; i < MAX_BRANDS; i++) { 208 if (elf_brand_list[i] == NULL) { 209 elf_brand_list[i] = entry; 210 break; 211 } 212 } 213 if (i == MAX_BRANDS) { 214 printf("WARNING: %s: could not insert brandinfo entry: %p\n", 215 __func__, entry); 216 return (-1); 217 } 218 return (0); 219 } 220 221 int 222 __elfN(remove_brand_entry)(Elf_Brandinfo *entry) 223 { 224 int i; 225 226 for (i = 0; i < MAX_BRANDS; i++) { 227 if (elf_brand_list[i] == entry) { 228 elf_brand_list[i] = NULL; 229 break; 230 } 231 } 232 if (i == MAX_BRANDS) 233 return (-1); 234 return (0); 235 } 236 237 int 238 __elfN(brand_inuse)(Elf_Brandinfo *entry) 239 { 240 struct proc *p; 241 int rval = FALSE; 242 243 sx_slock(&allproc_lock); 244 FOREACH_PROC_IN_SYSTEM(p) { 245 if (p->p_sysent == entry->sysvec) { 246 rval = TRUE; 247 break; 248 } 249 } 250 sx_sunlock(&allproc_lock); 251 252 return (rval); 253 } 254 255 static Elf_Brandinfo * 256 __elfN(get_brandinfo)(struct image_params *imgp, const char *interp, 257 int interp_name_len, int32_t *osrel) 258 { 259 const Elf_Ehdr *hdr = (const Elf_Ehdr *)imgp->image_header; 260 Elf_Brandinfo *bi; 261 boolean_t ret; 262 int i; 263 264 /* 265 * We support four types of branding -- (1) the ELF EI_OSABI field 266 * that SCO added to the ELF spec, (2) FreeBSD 3.x's traditional string 267 * branding w/in the ELF header, (3) path of the `interp_path' 268 * field, and (4) the ".note.ABI-tag" ELF section. 269 */ 270 271 /* Look for an ".note.ABI-tag" ELF section */ 272 for (i = 0; i < MAX_BRANDS; i++) { 273 bi = elf_brand_list[i]; 274 if (bi == NULL) 275 continue; 276 if (hdr->e_machine == bi->machine && (bi->flags & 277 (BI_BRAND_NOTE|BI_BRAND_NOTE_MANDATORY)) != 0) { 278 ret = __elfN(check_note)(imgp, bi->brand_note, osrel); 279 if (ret) 280 return (bi); 281 } 282 } 283 284 /* If the executable has a brand, search for it in the brand list. */ 285 for (i = 0; i < MAX_BRANDS; i++) { 286 bi = elf_brand_list[i]; 287 if (bi == NULL || bi->flags & BI_BRAND_NOTE_MANDATORY) 288 continue; 289 if (hdr->e_machine == bi->machine && 290 (hdr->e_ident[EI_OSABI] == bi->brand || 291 strncmp((const char *)&hdr->e_ident[OLD_EI_BRAND], 292 bi->compat_3_brand, strlen(bi->compat_3_brand)) == 0)) 293 return (bi); 294 } 295 296 /* Lacking a known brand, search for a recognized interpreter. */ 297 if (interp != NULL) { 298 for (i = 0; i < MAX_BRANDS; i++) { 299 bi = elf_brand_list[i]; 300 if (bi == NULL || bi->flags & BI_BRAND_NOTE_MANDATORY) 301 continue; 302 if (hdr->e_machine == bi->machine && 303 /* ELF image p_filesz includes terminating zero */ 304 strlen(bi->interp_path) + 1 == interp_name_len && 305 strncmp(interp, bi->interp_path, interp_name_len) 306 == 0) 307 return (bi); 308 } 309 } 310 311 /* Lacking a recognized interpreter, try the default brand */ 312 for (i = 0; i < MAX_BRANDS; i++) { 313 bi = elf_brand_list[i]; 314 if (bi == NULL || bi->flags & BI_BRAND_NOTE_MANDATORY) 315 continue; 316 if (hdr->e_machine == bi->machine && 317 __elfN(fallback_brand) == bi->brand) 318 return (bi); 319 } 320 return (NULL); 321 } 322 323 static int 324 __elfN(check_header)(const Elf_Ehdr *hdr) 325 { 326 Elf_Brandinfo *bi; 327 int i; 328 329 if (!IS_ELF(*hdr) || 330 hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS || 331 hdr->e_ident[EI_DATA] != ELF_TARG_DATA || 332 hdr->e_ident[EI_VERSION] != EV_CURRENT || 333 hdr->e_phentsize != sizeof(Elf_Phdr) || 334 hdr->e_version != ELF_TARG_VER) 335 return (ENOEXEC); 336 337 /* 338 * Make sure we have at least one brand for this machine. 339 */ 340 341 for (i = 0; i < MAX_BRANDS; i++) { 342 bi = elf_brand_list[i]; 343 if (bi != NULL && bi->machine == hdr->e_machine) 344 break; 345 } 346 if (i == MAX_BRANDS) 347 return (ENOEXEC); 348 349 return (0); 350 } 351 352 static int 353 __elfN(map_partial)(vm_map_t map, vm_object_t object, vm_ooffset_t offset, 354 vm_offset_t start, vm_offset_t end, vm_prot_t prot) 355 { 356 struct sf_buf *sf; 357 int error; 358 vm_offset_t off; 359 360 /* 361 * Create the page if it doesn't exist yet. Ignore errors. 362 */ 363 vm_map_lock(map); 364 vm_map_insert(map, NULL, 0, trunc_page(start), round_page(end), 365 VM_PROT_ALL, VM_PROT_ALL, 0); 366 vm_map_unlock(map); 367 368 /* 369 * Find the page from the underlying object. 370 */ 371 if (object) { 372 sf = vm_imgact_map_page(object, offset); 373 if (sf == NULL) 374 return (KERN_FAILURE); 375 off = offset - trunc_page(offset); 376 error = copyout((caddr_t)sf_buf_kva(sf) + off, (caddr_t)start, 377 end - start); 378 vm_imgact_unmap_page(sf); 379 if (error) { 380 return (KERN_FAILURE); 381 } 382 } 383 384 return (KERN_SUCCESS); 385 } 386 387 static int 388 __elfN(map_insert)(vm_map_t map, vm_object_t object, vm_ooffset_t offset, 389 vm_offset_t start, vm_offset_t end, vm_prot_t prot, int cow) 390 { 391 struct sf_buf *sf; 392 vm_offset_t off; 393 vm_size_t sz; 394 int error, rv; 395 396 if (start != trunc_page(start)) { 397 rv = __elfN(map_partial)(map, object, offset, start, 398 round_page(start), prot); 399 if (rv) 400 return (rv); 401 offset += round_page(start) - start; 402 start = round_page(start); 403 } 404 if (end != round_page(end)) { 405 rv = __elfN(map_partial)(map, object, offset + 406 trunc_page(end) - start, trunc_page(end), end, prot); 407 if (rv) 408 return (rv); 409 end = trunc_page(end); 410 } 411 if (end > start) { 412 if (offset & PAGE_MASK) { 413 /* 414 * The mapping is not page aligned. This means we have 415 * to copy the data. Sigh. 416 */ 417 rv = vm_map_find(map, NULL, 0, &start, end - start, 418 FALSE, prot | VM_PROT_WRITE, VM_PROT_ALL, 0); 419 if (rv) 420 return (rv); 421 if (object == NULL) 422 return (KERN_SUCCESS); 423 for (; start < end; start += sz) { 424 sf = vm_imgact_map_page(object, offset); 425 if (sf == NULL) 426 return (KERN_FAILURE); 427 off = offset - trunc_page(offset); 428 sz = end - start; 429 if (sz > PAGE_SIZE - off) 430 sz = PAGE_SIZE - off; 431 error = copyout((caddr_t)sf_buf_kva(sf) + off, 432 (caddr_t)start, sz); 433 vm_imgact_unmap_page(sf); 434 if (error) { 435 return (KERN_FAILURE); 436 } 437 offset += sz; 438 } 439 rv = KERN_SUCCESS; 440 } else { 441 vm_object_reference(object); 442 vm_map_lock(map); 443 rv = vm_map_insert(map, object, offset, start, end, 444 prot, VM_PROT_ALL, cow); 445 vm_map_unlock(map); 446 if (rv != KERN_SUCCESS) 447 vm_object_deallocate(object); 448 } 449 return (rv); 450 } else { 451 return (KERN_SUCCESS); 452 } 453 } 454 455 static int 456 __elfN(load_section)(struct vmspace *vmspace, 457 vm_object_t object, vm_offset_t offset, 458 caddr_t vmaddr, size_t memsz, size_t filsz, vm_prot_t prot, 459 size_t pagesize) 460 { 461 struct sf_buf *sf; 462 size_t map_len; 463 vm_offset_t map_addr; 464 int error, rv, cow; 465 size_t copy_len; 466 vm_offset_t file_addr; 467 468 /* 469 * It's necessary to fail if the filsz + offset taken from the 470 * header is greater than the actual file pager object's size. 471 * If we were to allow this, then the vm_map_find() below would 472 * walk right off the end of the file object and into the ether. 473 * 474 * While I'm here, might as well check for something else that 475 * is invalid: filsz cannot be greater than memsz. 476 */ 477 if ((off_t)filsz + offset > object->un_pager.vnp.vnp_size || 478 filsz > memsz) { 479 uprintf("elf_load_section: truncated ELF file\n"); 480 return (ENOEXEC); 481 } 482 483 map_addr = trunc_page_ps((vm_offset_t)vmaddr, pagesize); 484 file_addr = trunc_page_ps(offset, pagesize); 485 486 /* 487 * We have two choices. We can either clear the data in the last page 488 * of an oversized mapping, or we can start the anon mapping a page 489 * early and copy the initialized data into that first page. We 490 * choose the second.. 491 */ 492 if (memsz > filsz) 493 map_len = trunc_page_ps(offset + filsz, pagesize) - file_addr; 494 else 495 map_len = round_page_ps(offset + filsz, pagesize) - file_addr; 496 497 if (map_len != 0) { 498 /* cow flags: don't dump readonly sections in core */ 499 cow = MAP_COPY_ON_WRITE | MAP_PREFAULT | 500 (prot & VM_PROT_WRITE ? 0 : MAP_DISABLE_COREDUMP); 501 502 rv = __elfN(map_insert)(&vmspace->vm_map, 503 object, 504 file_addr, /* file offset */ 505 map_addr, /* virtual start */ 506 map_addr + map_len,/* virtual end */ 507 prot, 508 cow); 509 if (rv != KERN_SUCCESS) 510 return (EINVAL); 511 512 /* we can stop now if we've covered it all */ 513 if (memsz == filsz) { 514 return (0); 515 } 516 } 517 518 519 /* 520 * We have to get the remaining bit of the file into the first part 521 * of the oversized map segment. This is normally because the .data 522 * segment in the file is extended to provide bss. It's a neat idea 523 * to try and save a page, but it's a pain in the behind to implement. 524 */ 525 copy_len = (offset + filsz) - trunc_page_ps(offset + filsz, pagesize); 526 map_addr = trunc_page_ps((vm_offset_t)vmaddr + filsz, pagesize); 527 map_len = round_page_ps((vm_offset_t)vmaddr + memsz, pagesize) - 528 map_addr; 529 530 /* This had damn well better be true! */ 531 if (map_len != 0) { 532 rv = __elfN(map_insert)(&vmspace->vm_map, NULL, 0, map_addr, 533 map_addr + map_len, VM_PROT_ALL, 0); 534 if (rv != KERN_SUCCESS) { 535 return (EINVAL); 536 } 537 } 538 539 if (copy_len != 0) { 540 vm_offset_t off; 541 542 sf = vm_imgact_map_page(object, offset + filsz); 543 if (sf == NULL) 544 return (EIO); 545 546 /* send the page fragment to user space */ 547 off = trunc_page_ps(offset + filsz, pagesize) - 548 trunc_page(offset + filsz); 549 error = copyout((caddr_t)sf_buf_kva(sf) + off, 550 (caddr_t)map_addr, copy_len); 551 vm_imgact_unmap_page(sf); 552 if (error) { 553 return (error); 554 } 555 } 556 557 /* 558 * set it to the specified protection. 559 * XXX had better undo the damage from pasting over the cracks here! 560 */ 561 vm_map_protect(&vmspace->vm_map, trunc_page(map_addr), 562 round_page(map_addr + map_len), prot, FALSE); 563 564 return (0); 565 } 566 567 /* 568 * Load the file "file" into memory. It may be either a shared object 569 * or an executable. 570 * 571 * The "addr" reference parameter is in/out. On entry, it specifies 572 * the address where a shared object should be loaded. If the file is 573 * an executable, this value is ignored. On exit, "addr" specifies 574 * where the file was actually loaded. 575 * 576 * The "entry" reference parameter is out only. On exit, it specifies 577 * the entry point for the loaded file. 578 */ 579 static int 580 __elfN(load_file)(struct proc *p, const char *file, u_long *addr, 581 u_long *entry, size_t pagesize) 582 { 583 struct { 584 struct nameidata nd; 585 struct vattr attr; 586 struct image_params image_params; 587 } *tempdata; 588 const Elf_Ehdr *hdr = NULL; 589 const Elf_Phdr *phdr = NULL; 590 struct nameidata *nd; 591 struct vmspace *vmspace = p->p_vmspace; 592 struct vattr *attr; 593 struct image_params *imgp; 594 vm_prot_t prot; 595 u_long rbase; 596 u_long base_addr = 0; 597 int vfslocked, error, i, numsegs; 598 599 #ifdef CAPABILITY_MODE 600 /* 601 * XXXJA: This check can go away once we are sufficiently confident 602 * that the checks in namei() are correct. 603 */ 604 if (IN_CAPABILITY_MODE(curthread)) 605 return (ECAPMODE); 606 #endif 607 608 tempdata = malloc(sizeof(*tempdata), M_TEMP, M_WAITOK); 609 nd = &tempdata->nd; 610 attr = &tempdata->attr; 611 imgp = &tempdata->image_params; 612 613 /* 614 * Initialize part of the common data 615 */ 616 imgp->proc = p; 617 imgp->attr = attr; 618 imgp->firstpage = NULL; 619 imgp->image_header = NULL; 620 imgp->object = NULL; 621 imgp->execlabel = NULL; 622 623 NDINIT(nd, LOOKUP, MPSAFE|LOCKLEAF|FOLLOW, UIO_SYSSPACE, file, 624 curthread); 625 vfslocked = 0; 626 if ((error = namei(nd)) != 0) { 627 nd->ni_vp = NULL; 628 goto fail; 629 } 630 vfslocked = NDHASGIANT(nd); 631 NDFREE(nd, NDF_ONLY_PNBUF); 632 imgp->vp = nd->ni_vp; 633 634 /* 635 * Check permissions, modes, uid, etc on the file, and "open" it. 636 */ 637 error = exec_check_permissions(imgp); 638 if (error) 639 goto fail; 640 641 error = exec_map_first_page(imgp); 642 if (error) 643 goto fail; 644 645 /* 646 * Also make certain that the interpreter stays the same, so set 647 * its VV_TEXT flag, too. 648 */ 649 nd->ni_vp->v_vflag |= VV_TEXT; 650 651 imgp->object = nd->ni_vp->v_object; 652 653 hdr = (const Elf_Ehdr *)imgp->image_header; 654 if ((error = __elfN(check_header)(hdr)) != 0) 655 goto fail; 656 if (hdr->e_type == ET_DYN) 657 rbase = *addr; 658 else if (hdr->e_type == ET_EXEC) 659 rbase = 0; 660 else { 661 error = ENOEXEC; 662 goto fail; 663 } 664 665 /* Only support headers that fit within first page for now */ 666 /* (multiplication of two Elf_Half fields will not overflow) */ 667 if ((hdr->e_phoff > PAGE_SIZE) || 668 (hdr->e_phentsize * hdr->e_phnum) > PAGE_SIZE - hdr->e_phoff) { 669 error = ENOEXEC; 670 goto fail; 671 } 672 673 phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff); 674 if (!aligned(phdr, Elf_Addr)) { 675 error = ENOEXEC; 676 goto fail; 677 } 678 679 for (i = 0, numsegs = 0; i < hdr->e_phnum; i++) { 680 if (phdr[i].p_type == PT_LOAD && phdr[i].p_memsz != 0) { 681 /* Loadable segment */ 682 prot = __elfN(trans_prot)(phdr[i].p_flags); 683 if ((error = __elfN(load_section)(vmspace, 684 imgp->object, phdr[i].p_offset, 685 (caddr_t)(uintptr_t)phdr[i].p_vaddr + rbase, 686 phdr[i].p_memsz, phdr[i].p_filesz, prot, 687 pagesize)) != 0) 688 goto fail; 689 /* 690 * Establish the base address if this is the 691 * first segment. 692 */ 693 if (numsegs == 0) 694 base_addr = trunc_page(phdr[i].p_vaddr + 695 rbase); 696 numsegs++; 697 } 698 } 699 *addr = base_addr; 700 *entry = (unsigned long)hdr->e_entry + rbase; 701 702 fail: 703 if (imgp->firstpage) 704 exec_unmap_first_page(imgp); 705 706 if (nd->ni_vp) 707 vput(nd->ni_vp); 708 709 VFS_UNLOCK_GIANT(vfslocked); 710 free(tempdata, M_TEMP); 711 712 return (error); 713 } 714 715 static int 716 __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp) 717 { 718 const Elf_Ehdr *hdr = (const Elf_Ehdr *)imgp->image_header; 719 const Elf_Phdr *phdr; 720 Elf_Auxargs *elf_auxargs; 721 struct vmspace *vmspace; 722 vm_prot_t prot; 723 u_long text_size = 0, data_size = 0, total_size = 0; 724 u_long text_addr = 0, data_addr = 0; 725 u_long seg_size, seg_addr; 726 u_long addr, baddr, et_dyn_addr, entry = 0, proghdr = 0; 727 int32_t osrel = 0; 728 int error = 0, i, n, interp_name_len = 0; 729 const char *interp = NULL, *newinterp = NULL; 730 Elf_Brandinfo *brand_info; 731 char *path; 732 struct sysentvec *sv; 733 734 /* 735 * Do we have a valid ELF header ? 736 * 737 * Only allow ET_EXEC & ET_DYN here, reject ET_DYN later 738 * if particular brand doesn't support it. 739 */ 740 if (__elfN(check_header)(hdr) != 0 || 741 (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN)) 742 return (-1); 743 744 /* 745 * From here on down, we return an errno, not -1, as we've 746 * detected an ELF file. 747 */ 748 749 if ((hdr->e_phoff > PAGE_SIZE) || 750 (hdr->e_phoff + hdr->e_phentsize * hdr->e_phnum) > PAGE_SIZE) { 751 /* Only support headers in first page for now */ 752 return (ENOEXEC); 753 } 754 phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff); 755 if (!aligned(phdr, Elf_Addr)) 756 return (ENOEXEC); 757 n = 0; 758 baddr = 0; 759 for (i = 0; i < hdr->e_phnum; i++) { 760 switch (phdr[i].p_type) { 761 case PT_LOAD: 762 if (n == 0) 763 baddr = phdr[i].p_vaddr; 764 n++; 765 break; 766 case PT_INTERP: 767 /* Path to interpreter */ 768 if (phdr[i].p_filesz > MAXPATHLEN || 769 phdr[i].p_offset >= PAGE_SIZE || 770 phdr[i].p_offset + phdr[i].p_filesz >= PAGE_SIZE) 771 return (ENOEXEC); 772 interp = imgp->image_header + phdr[i].p_offset; 773 interp_name_len = phdr[i].p_filesz; 774 break; 775 case PT_GNU_STACK: 776 if (__elfN(nxstack)) 777 imgp->stack_prot = 778 __elfN(trans_prot)(phdr[i].p_flags); 779 break; 780 } 781 } 782 783 brand_info = __elfN(get_brandinfo)(imgp, interp, interp_name_len, 784 &osrel); 785 if (brand_info == NULL) { 786 uprintf("ELF binary type \"%u\" not known.\n", 787 hdr->e_ident[EI_OSABI]); 788 return (ENOEXEC); 789 } 790 if (hdr->e_type == ET_DYN) { 791 if ((brand_info->flags & BI_CAN_EXEC_DYN) == 0) 792 return (ENOEXEC); 793 /* 794 * Honour the base load address from the dso if it is 795 * non-zero for some reason. 796 */ 797 if (baddr == 0) 798 et_dyn_addr = ET_DYN_LOAD_ADDR; 799 else 800 et_dyn_addr = 0; 801 } else 802 et_dyn_addr = 0; 803 sv = brand_info->sysvec; 804 if (interp != NULL && brand_info->interp_newpath != NULL) 805 newinterp = brand_info->interp_newpath; 806 807 /* 808 * Avoid a possible deadlock if the current address space is destroyed 809 * and that address space maps the locked vnode. In the common case, 810 * the locked vnode's v_usecount is decremented but remains greater 811 * than zero. Consequently, the vnode lock is not needed by vrele(). 812 * However, in cases where the vnode lock is external, such as nullfs, 813 * v_usecount may become zero. 814 */ 815 VOP_UNLOCK(imgp->vp, 0); 816 817 error = exec_new_vmspace(imgp, sv); 818 imgp->proc->p_sysent = sv; 819 820 vn_lock(imgp->vp, LK_EXCLUSIVE | LK_RETRY); 821 if (error) 822 return (error); 823 824 vmspace = imgp->proc->p_vmspace; 825 826 for (i = 0; i < hdr->e_phnum; i++) { 827 switch (phdr[i].p_type) { 828 case PT_LOAD: /* Loadable segment */ 829 if (phdr[i].p_memsz == 0) 830 break; 831 prot = __elfN(trans_prot)(phdr[i].p_flags); 832 833 #if defined(__ia64__) && __ELF_WORD_SIZE == 32 && defined(IA32_ME_HARDER) 834 /* 835 * Some x86 binaries assume read == executable, 836 * notably the M3 runtime and therefore cvsup 837 */ 838 if (prot & VM_PROT_READ) 839 prot |= VM_PROT_EXECUTE; 840 #endif 841 842 if ((error = __elfN(load_section)(vmspace, 843 imgp->object, phdr[i].p_offset, 844 (caddr_t)(uintptr_t)phdr[i].p_vaddr + et_dyn_addr, 845 phdr[i].p_memsz, phdr[i].p_filesz, prot, 846 sv->sv_pagesize)) != 0) 847 return (error); 848 849 /* 850 * If this segment contains the program headers, 851 * remember their virtual address for the AT_PHDR 852 * aux entry. Static binaries don't usually include 853 * a PT_PHDR entry. 854 */ 855 if (phdr[i].p_offset == 0 && 856 hdr->e_phoff + hdr->e_phnum * hdr->e_phentsize 857 <= phdr[i].p_filesz) 858 proghdr = phdr[i].p_vaddr + hdr->e_phoff + 859 et_dyn_addr; 860 861 seg_addr = trunc_page(phdr[i].p_vaddr + et_dyn_addr); 862 seg_size = round_page(phdr[i].p_memsz + 863 phdr[i].p_vaddr + et_dyn_addr - seg_addr); 864 865 /* 866 * Make the largest executable segment the official 867 * text segment and all others data. 868 * 869 * Note that obreak() assumes that data_addr + 870 * data_size == end of data load area, and the ELF 871 * file format expects segments to be sorted by 872 * address. If multiple data segments exist, the 873 * last one will be used. 874 */ 875 876 if (phdr[i].p_flags & PF_X && text_size < seg_size) { 877 text_size = seg_size; 878 text_addr = seg_addr; 879 } else { 880 data_size = seg_size; 881 data_addr = seg_addr; 882 } 883 total_size += seg_size; 884 break; 885 case PT_PHDR: /* Program header table info */ 886 proghdr = phdr[i].p_vaddr + et_dyn_addr; 887 break; 888 default: 889 break; 890 } 891 } 892 893 if (data_addr == 0 && data_size == 0) { 894 data_addr = text_addr; 895 data_size = text_size; 896 } 897 898 entry = (u_long)hdr->e_entry + et_dyn_addr; 899 900 /* 901 * Check limits. It should be safe to check the 902 * limits after loading the segments since we do 903 * not actually fault in all the segments pages. 904 */ 905 PROC_LOCK(imgp->proc); 906 if (data_size > lim_cur(imgp->proc, RLIMIT_DATA) || 907 text_size > maxtsiz || 908 total_size > lim_cur(imgp->proc, RLIMIT_VMEM) || 909 racct_set(imgp->proc, RACCT_DATA, data_size) != 0 || 910 racct_set(imgp->proc, RACCT_VMEM, total_size) != 0) { 911 PROC_UNLOCK(imgp->proc); 912 return (ENOMEM); 913 } 914 915 vmspace->vm_tsize = text_size >> PAGE_SHIFT; 916 vmspace->vm_taddr = (caddr_t)(uintptr_t)text_addr; 917 vmspace->vm_dsize = data_size >> PAGE_SHIFT; 918 vmspace->vm_daddr = (caddr_t)(uintptr_t)data_addr; 919 920 /* 921 * We load the dynamic linker where a userland call 922 * to mmap(0, ...) would put it. The rationale behind this 923 * calculation is that it leaves room for the heap to grow to 924 * its maximum allowed size. 925 */ 926 addr = round_page((vm_offset_t)imgp->proc->p_vmspace->vm_daddr + 927 lim_max(imgp->proc, RLIMIT_DATA)); 928 PROC_UNLOCK(imgp->proc); 929 930 imgp->entry_addr = entry; 931 932 if (interp != NULL) { 933 int have_interp = FALSE; 934 VOP_UNLOCK(imgp->vp, 0); 935 if (brand_info->emul_path != NULL && 936 brand_info->emul_path[0] != '\0') { 937 path = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 938 snprintf(path, MAXPATHLEN, "%s%s", 939 brand_info->emul_path, interp); 940 error = __elfN(load_file)(imgp->proc, path, &addr, 941 &imgp->entry_addr, sv->sv_pagesize); 942 free(path, M_TEMP); 943 if (error == 0) 944 have_interp = TRUE; 945 } 946 if (!have_interp && newinterp != NULL) { 947 error = __elfN(load_file)(imgp->proc, newinterp, &addr, 948 &imgp->entry_addr, sv->sv_pagesize); 949 if (error == 0) 950 have_interp = TRUE; 951 } 952 if (!have_interp) { 953 error = __elfN(load_file)(imgp->proc, interp, &addr, 954 &imgp->entry_addr, sv->sv_pagesize); 955 } 956 vn_lock(imgp->vp, LK_EXCLUSIVE | LK_RETRY); 957 if (error != 0) { 958 uprintf("ELF interpreter %s not found\n", interp); 959 return (error); 960 } 961 } else 962 addr = et_dyn_addr; 963 964 /* 965 * Construct auxargs table (used by the fixup routine) 966 */ 967 elf_auxargs = malloc(sizeof(Elf_Auxargs), M_TEMP, M_WAITOK); 968 elf_auxargs->execfd = -1; 969 elf_auxargs->phdr = proghdr; 970 elf_auxargs->phent = hdr->e_phentsize; 971 elf_auxargs->phnum = hdr->e_phnum; 972 elf_auxargs->pagesz = PAGE_SIZE; 973 elf_auxargs->base = addr; 974 elf_auxargs->flags = 0; 975 elf_auxargs->entry = entry; 976 977 imgp->auxargs = elf_auxargs; 978 imgp->interpreted = 0; 979 imgp->reloc_base = addr; 980 imgp->proc->p_osrel = osrel; 981 982 return (error); 983 } 984 985 #define suword __CONCAT(suword, __ELF_WORD_SIZE) 986 987 int 988 __elfN(freebsd_fixup)(register_t **stack_base, struct image_params *imgp) 989 { 990 Elf_Auxargs *args = (Elf_Auxargs *)imgp->auxargs; 991 Elf_Addr *base; 992 Elf_Addr *pos; 993 994 base = (Elf_Addr *)*stack_base; 995 pos = base + (imgp->args->argc + imgp->args->envc + 2); 996 997 if (args->execfd != -1) 998 AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd); 999 AUXARGS_ENTRY(pos, AT_PHDR, args->phdr); 1000 AUXARGS_ENTRY(pos, AT_PHENT, args->phent); 1001 AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum); 1002 AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz); 1003 AUXARGS_ENTRY(pos, AT_FLAGS, args->flags); 1004 AUXARGS_ENTRY(pos, AT_ENTRY, args->entry); 1005 AUXARGS_ENTRY(pos, AT_BASE, args->base); 1006 if (imgp->execpathp != 0) 1007 AUXARGS_ENTRY(pos, AT_EXECPATH, imgp->execpathp); 1008 AUXARGS_ENTRY(pos, AT_OSRELDATE, osreldate); 1009 if (imgp->canary != 0) { 1010 AUXARGS_ENTRY(pos, AT_CANARY, imgp->canary); 1011 AUXARGS_ENTRY(pos, AT_CANARYLEN, imgp->canarylen); 1012 } 1013 AUXARGS_ENTRY(pos, AT_NCPUS, mp_ncpus); 1014 if (imgp->pagesizes != 0) { 1015 AUXARGS_ENTRY(pos, AT_PAGESIZES, imgp->pagesizes); 1016 AUXARGS_ENTRY(pos, AT_PAGESIZESLEN, imgp->pagesizeslen); 1017 } 1018 AUXARGS_ENTRY(pos, AT_STACKPROT, imgp->sysent->sv_shared_page_obj 1019 != NULL && imgp->stack_prot != 0 ? imgp->stack_prot : 1020 imgp->sysent->sv_stackprot); 1021 AUXARGS_ENTRY(pos, AT_NULL, 0); 1022 1023 free(imgp->auxargs, M_TEMP); 1024 imgp->auxargs = NULL; 1025 1026 base--; 1027 suword(base, (long)imgp->args->argc); 1028 *stack_base = (register_t *)base; 1029 return (0); 1030 } 1031 1032 /* 1033 * Code for generating ELF core dumps. 1034 */ 1035 1036 typedef void (*segment_callback)(vm_map_entry_t, void *); 1037 1038 /* Closure for cb_put_phdr(). */ 1039 struct phdr_closure { 1040 Elf_Phdr *phdr; /* Program header to fill in */ 1041 Elf_Off offset; /* Offset of segment in core file */ 1042 }; 1043 1044 /* Closure for cb_size_segment(). */ 1045 struct sseg_closure { 1046 int count; /* Count of writable segments. */ 1047 size_t size; /* Total size of all writable segments. */ 1048 }; 1049 1050 static void cb_put_phdr(vm_map_entry_t, void *); 1051 static void cb_size_segment(vm_map_entry_t, void *); 1052 static void each_writable_segment(struct thread *, segment_callback, void *); 1053 static int __elfN(corehdr)(struct thread *, struct vnode *, struct ucred *, 1054 int, void *, size_t, gzFile); 1055 static void __elfN(puthdr)(struct thread *, void *, size_t *, int); 1056 static void __elfN(putnote)(void *, size_t *, const char *, int, 1057 const void *, size_t); 1058 1059 #ifdef COMPRESS_USER_CORES 1060 extern int compress_user_cores; 1061 extern int compress_user_cores_gzlevel; 1062 #endif 1063 1064 static int 1065 core_output(struct vnode *vp, void *base, size_t len, off_t offset, 1066 struct ucred *active_cred, struct ucred *file_cred, 1067 struct thread *td, char *core_buf, gzFile gzfile) { 1068 1069 int error; 1070 if (gzfile) { 1071 #ifdef COMPRESS_USER_CORES 1072 error = compress_core(gzfile, base, core_buf, len, td); 1073 #else 1074 panic("shouldn't be here"); 1075 #endif 1076 } else { 1077 error = vn_rdwr_inchunks(UIO_WRITE, vp, base, len, offset, 1078 UIO_USERSPACE, IO_UNIT | IO_DIRECT, active_cred, file_cred, 1079 NULL, td); 1080 } 1081 return (error); 1082 } 1083 1084 int 1085 __elfN(coredump)(struct thread *td, struct vnode *vp, off_t limit, int flags) 1086 { 1087 struct ucred *cred = td->td_ucred; 1088 int error = 0; 1089 struct sseg_closure seginfo; 1090 void *hdr; 1091 size_t hdrsize; 1092 1093 gzFile gzfile = Z_NULL; 1094 char *core_buf = NULL; 1095 #ifdef COMPRESS_USER_CORES 1096 char gzopen_flags[8]; 1097 char *p; 1098 int doing_compress = flags & IMGACT_CORE_COMPRESS; 1099 #endif 1100 1101 hdr = NULL; 1102 1103 #ifdef COMPRESS_USER_CORES 1104 if (doing_compress) { 1105 p = gzopen_flags; 1106 *p++ = 'w'; 1107 if (compress_user_cores_gzlevel >= 0 && 1108 compress_user_cores_gzlevel <= 9) 1109 *p++ = '' + compress_user_cores_gzlevel; 1110 *p = 0; 1111 gzfile = gz_open("", gzopen_flags, vp); 1112 if (gzfile == Z_NULL) { 1113 error = EFAULT; 1114 goto done; 1115 } 1116 core_buf = malloc(CORE_BUF_SIZE, M_TEMP, M_WAITOK | M_ZERO); 1117 if (!core_buf) { 1118 error = ENOMEM; 1119 goto done; 1120 } 1121 } 1122 #endif 1123 1124 /* Size the program segments. */ 1125 seginfo.count = 0; 1126 seginfo.size = 0; 1127 each_writable_segment(td, cb_size_segment, &seginfo); 1128 1129 /* 1130 * Calculate the size of the core file header area by making 1131 * a dry run of generating it. Nothing is written, but the 1132 * size is calculated. 1133 */ 1134 hdrsize = 0; 1135 __elfN(puthdr)(td, (void *)NULL, &hdrsize, seginfo.count); 1136 1137 #ifdef RACCT 1138 PROC_LOCK(td->td_proc); 1139 error = racct_add(td->td_proc, RACCT_CORE, hdrsize + seginfo.size); 1140 PROC_UNLOCK(td->td_proc); 1141 if (error != 0) { 1142 error = EFAULT; 1143 goto done; 1144 } 1145 #endif 1146 if (hdrsize + seginfo.size >= limit) { 1147 error = EFAULT; 1148 goto done; 1149 } 1150 1151 /* 1152 * Allocate memory for building the header, fill it up, 1153 * and write it out. 1154 */ 1155 hdr = malloc(hdrsize, M_TEMP, M_WAITOK); 1156 if (hdr == NULL) { 1157 error = EINVAL; 1158 goto done; 1159 } 1160 error = __elfN(corehdr)(td, vp, cred, seginfo.count, hdr, hdrsize, 1161 gzfile); 1162 1163 /* Write the contents of all of the writable segments. */ 1164 if (error == 0) { 1165 Elf_Phdr *php; 1166 off_t offset; 1167 int i; 1168 1169 php = (Elf_Phdr *)((char *)hdr + sizeof(Elf_Ehdr)) + 1; 1170 offset = hdrsize; 1171 for (i = 0; i < seginfo.count; i++) { 1172 error = core_output(vp, (caddr_t)(uintptr_t)php->p_vaddr, 1173 php->p_filesz, offset, cred, NOCRED, curthread, core_buf, gzfile); 1174 if (error != 0) 1175 break; 1176 offset += php->p_filesz; 1177 php++; 1178 } 1179 } 1180 if (error) { 1181 log(LOG_WARNING, 1182 "Failed to write core file for process %s (error %d)\n", 1183 curproc->p_comm, error); 1184 } 1185 1186 done: 1187 #ifdef COMPRESS_USER_CORES 1188 if (core_buf) 1189 free(core_buf, M_TEMP); 1190 if (gzfile) 1191 gzclose(gzfile); 1192 #endif 1193 1194 free(hdr, M_TEMP); 1195 1196 return (error); 1197 } 1198 1199 /* 1200 * A callback for each_writable_segment() to write out the segment's 1201 * program header entry. 1202 */ 1203 static void 1204 cb_put_phdr(entry, closure) 1205 vm_map_entry_t entry; 1206 void *closure; 1207 { 1208 struct phdr_closure *phc = (struct phdr_closure *)closure; 1209 Elf_Phdr *phdr = phc->phdr; 1210 1211 phc->offset = round_page(phc->offset); 1212 1213 phdr->p_type = PT_LOAD; 1214 phdr->p_offset = phc->offset; 1215 phdr->p_vaddr = entry->start; 1216 phdr->p_paddr = 0; 1217 phdr->p_filesz = phdr->p_memsz = entry->end - entry->start; 1218 phdr->p_align = PAGE_SIZE; 1219 phdr->p_flags = __elfN(untrans_prot)(entry->protection); 1220 1221 phc->offset += phdr->p_filesz; 1222 phc->phdr++; 1223 } 1224 1225 /* 1226 * A callback for each_writable_segment() to gather information about 1227 * the number of segments and their total size. 1228 */ 1229 static void 1230 cb_size_segment(entry, closure) 1231 vm_map_entry_t entry; 1232 void *closure; 1233 { 1234 struct sseg_closure *ssc = (struct sseg_closure *)closure; 1235 1236 ssc->count++; 1237 ssc->size += entry->end - entry->start; 1238 } 1239 1240 /* 1241 * For each writable segment in the process's memory map, call the given 1242 * function with a pointer to the map entry and some arbitrary 1243 * caller-supplied data. 1244 */ 1245 static void 1246 each_writable_segment(td, func, closure) 1247 struct thread *td; 1248 segment_callback func; 1249 void *closure; 1250 { 1251 struct proc *p = td->td_proc; 1252 vm_map_t map = &p->p_vmspace->vm_map; 1253 vm_map_entry_t entry; 1254 vm_object_t backing_object, object; 1255 boolean_t ignore_entry; 1256 1257 vm_map_lock_read(map); 1258 for (entry = map->header.next; entry != &map->header; 1259 entry = entry->next) { 1260 /* 1261 * Don't dump inaccessible mappings, deal with legacy 1262 * coredump mode. 1263 * 1264 * Note that read-only segments related to the elf binary 1265 * are marked MAP_ENTRY_NOCOREDUMP now so we no longer 1266 * need to arbitrarily ignore such segments. 1267 */ 1268 if (elf_legacy_coredump) { 1269 if ((entry->protection & VM_PROT_RW) != VM_PROT_RW) 1270 continue; 1271 } else { 1272 if ((entry->protection & VM_PROT_ALL) == 0) 1273 continue; 1274 } 1275 1276 /* 1277 * Dont include memory segment in the coredump if 1278 * MAP_NOCORE is set in mmap(2) or MADV_NOCORE in 1279 * madvise(2). Do not dump submaps (i.e. parts of the 1280 * kernel map). 1281 */ 1282 if (entry->eflags & (MAP_ENTRY_NOCOREDUMP|MAP_ENTRY_IS_SUB_MAP)) 1283 continue; 1284 1285 if ((object = entry->object.vm_object) == NULL) 1286 continue; 1287 1288 /* Ignore memory-mapped devices and such things. */ 1289 VM_OBJECT_LOCK(object); 1290 while ((backing_object = object->backing_object) != NULL) { 1291 VM_OBJECT_LOCK(backing_object); 1292 VM_OBJECT_UNLOCK(object); 1293 object = backing_object; 1294 } 1295 ignore_entry = object->type != OBJT_DEFAULT && 1296 object->type != OBJT_SWAP && object->type != OBJT_VNODE; 1297 VM_OBJECT_UNLOCK(object); 1298 if (ignore_entry) 1299 continue; 1300 1301 (*func)(entry, closure); 1302 } 1303 vm_map_unlock_read(map); 1304 } 1305 1306 /* 1307 * Write the core file header to the file, including padding up to 1308 * the page boundary. 1309 */ 1310 static int 1311 __elfN(corehdr)(td, vp, cred, numsegs, hdr, hdrsize, gzfile) 1312 struct thread *td; 1313 struct vnode *vp; 1314 struct ucred *cred; 1315 int numsegs; 1316 size_t hdrsize; 1317 void *hdr; 1318 gzFile gzfile; 1319 { 1320 size_t off; 1321 1322 /* Fill in the header. */ 1323 bzero(hdr, hdrsize); 1324 off = 0; 1325 __elfN(puthdr)(td, hdr, &off, numsegs); 1326 1327 if (!gzfile) { 1328 /* Write it to the core file. */ 1329 return (vn_rdwr_inchunks(UIO_WRITE, vp, hdr, hdrsize, (off_t)0, 1330 UIO_SYSSPACE, IO_UNIT | IO_DIRECT, cred, NOCRED, NULL, 1331 td)); 1332 } else { 1333 #ifdef COMPRESS_USER_CORES 1334 if (gzwrite(gzfile, hdr, hdrsize) != hdrsize) { 1335 log(LOG_WARNING, 1336 "Failed to compress core file header for process" 1337 " %s.\n", curproc->p_comm); 1338 return (EFAULT); 1339 } 1340 else { 1341 return (0); 1342 } 1343 #else 1344 panic("shouldn't be here"); 1345 #endif 1346 } 1347 } 1348 1349 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32 1350 #include <compat/freebsd32/freebsd32.h> 1351 1352 typedef struct prstatus32 elf_prstatus_t; 1353 typedef struct prpsinfo32 elf_prpsinfo_t; 1354 typedef struct fpreg32 elf_prfpregset_t; 1355 typedef struct fpreg32 elf_fpregset_t; 1356 typedef struct reg32 elf_gregset_t; 1357 typedef struct thrmisc32 elf_thrmisc_t; 1358 #else 1359 typedef prstatus_t elf_prstatus_t; 1360 typedef prpsinfo_t elf_prpsinfo_t; 1361 typedef prfpregset_t elf_prfpregset_t; 1362 typedef prfpregset_t elf_fpregset_t; 1363 typedef gregset_t elf_gregset_t; 1364 typedef thrmisc_t elf_thrmisc_t; 1365 #endif 1366 1367 static void 1368 __elfN(puthdr)(struct thread *td, void *dst, size_t *off, int numsegs) 1369 { 1370 struct { 1371 elf_prstatus_t status; 1372 elf_prfpregset_t fpregset; 1373 elf_prpsinfo_t psinfo; 1374 elf_thrmisc_t thrmisc; 1375 } *tempdata; 1376 elf_prstatus_t *status; 1377 elf_prfpregset_t *fpregset; 1378 elf_prpsinfo_t *psinfo; 1379 elf_thrmisc_t *thrmisc; 1380 struct proc *p; 1381 struct thread *thr; 1382 size_t ehoff, noteoff, notesz, phoff; 1383 1384 p = td->td_proc; 1385 1386 ehoff = *off; 1387 *off += sizeof(Elf_Ehdr); 1388 1389 phoff = *off; 1390 *off += (numsegs + 1) * sizeof(Elf_Phdr); 1391 1392 noteoff = *off; 1393 /* 1394 * Don't allocate space for the notes if we're just calculating 1395 * the size of the header. We also don't collect the data. 1396 */ 1397 if (dst != NULL) { 1398 tempdata = malloc(sizeof(*tempdata), M_TEMP, M_ZERO|M_WAITOK); 1399 status = &tempdata->status; 1400 fpregset = &tempdata->fpregset; 1401 psinfo = &tempdata->psinfo; 1402 thrmisc = &tempdata->thrmisc; 1403 } else { 1404 tempdata = NULL; 1405 status = NULL; 1406 fpregset = NULL; 1407 psinfo = NULL; 1408 thrmisc = NULL; 1409 } 1410 1411 if (dst != NULL) { 1412 psinfo->pr_version = PRPSINFO_VERSION; 1413 psinfo->pr_psinfosz = sizeof(elf_prpsinfo_t); 1414 strlcpy(psinfo->pr_fname, p->p_comm, sizeof(psinfo->pr_fname)); 1415 /* 1416 * XXX - We don't fill in the command line arguments properly 1417 * yet. 1418 */ 1419 strlcpy(psinfo->pr_psargs, p->p_comm, 1420 sizeof(psinfo->pr_psargs)); 1421 } 1422 __elfN(putnote)(dst, off, "FreeBSD", NT_PRPSINFO, psinfo, 1423 sizeof *psinfo); 1424 1425 /* 1426 * To have the debugger select the right thread (LWP) as the initial 1427 * thread, we dump the state of the thread passed to us in td first. 1428 * This is the thread that causes the core dump and thus likely to 1429 * be the right thread one wants to have selected in the debugger. 1430 */ 1431 thr = td; 1432 while (thr != NULL) { 1433 if (dst != NULL) { 1434 status->pr_version = PRSTATUS_VERSION; 1435 status->pr_statussz = sizeof(elf_prstatus_t); 1436 status->pr_gregsetsz = sizeof(elf_gregset_t); 1437 status->pr_fpregsetsz = sizeof(elf_fpregset_t); 1438 status->pr_osreldate = osreldate; 1439 status->pr_cursig = p->p_sig; 1440 status->pr_pid = thr->td_tid; 1441 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32 1442 fill_regs32(thr, &status->pr_reg); 1443 fill_fpregs32(thr, fpregset); 1444 #else 1445 fill_regs(thr, &status->pr_reg); 1446 fill_fpregs(thr, fpregset); 1447 #endif 1448 memset(&thrmisc->_pad, 0, sizeof (thrmisc->_pad)); 1449 strcpy(thrmisc->pr_tname, thr->td_name); 1450 } 1451 __elfN(putnote)(dst, off, "FreeBSD", NT_PRSTATUS, status, 1452 sizeof *status); 1453 __elfN(putnote)(dst, off, "FreeBSD", NT_FPREGSET, fpregset, 1454 sizeof *fpregset); 1455 __elfN(putnote)(dst, off, "FreeBSD", NT_THRMISC, thrmisc, 1456 sizeof *thrmisc); 1457 /* 1458 * Allow for MD specific notes, as well as any MD 1459 * specific preparations for writing MI notes. 1460 */ 1461 __elfN(dump_thread)(thr, dst, off); 1462 1463 thr = (thr == td) ? TAILQ_FIRST(&p->p_threads) : 1464 TAILQ_NEXT(thr, td_plist); 1465 if (thr == td) 1466 thr = TAILQ_NEXT(thr, td_plist); 1467 } 1468 1469 notesz = *off - noteoff; 1470 1471 if (dst != NULL) 1472 free(tempdata, M_TEMP); 1473 1474 /* Align up to a page boundary for the program segments. */ 1475 *off = round_page(*off); 1476 1477 if (dst != NULL) { 1478 Elf_Ehdr *ehdr; 1479 Elf_Phdr *phdr; 1480 struct phdr_closure phc; 1481 1482 /* 1483 * Fill in the ELF header. 1484 */ 1485 ehdr = (Elf_Ehdr *)((char *)dst + ehoff); 1486 ehdr->e_ident[EI_MAG0] = ELFMAG0; 1487 ehdr->e_ident[EI_MAG1] = ELFMAG1; 1488 ehdr->e_ident[EI_MAG2] = ELFMAG2; 1489 ehdr->e_ident[EI_MAG3] = ELFMAG3; 1490 ehdr->e_ident[EI_CLASS] = ELF_CLASS; 1491 ehdr->e_ident[EI_DATA] = ELF_DATA; 1492 ehdr->e_ident[EI_VERSION] = EV_CURRENT; 1493 ehdr->e_ident[EI_OSABI] = ELFOSABI_FREEBSD; 1494 ehdr->e_ident[EI_ABIVERSION] = 0; 1495 ehdr->e_ident[EI_PAD] = 0; 1496 ehdr->e_type = ET_CORE; 1497 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32 1498 ehdr->e_machine = ELF_ARCH32; 1499 #else 1500 ehdr->e_machine = ELF_ARCH; 1501 #endif 1502 ehdr->e_version = EV_CURRENT; 1503 ehdr->e_entry = 0; 1504 ehdr->e_phoff = phoff; 1505 ehdr->e_flags = 0; 1506 ehdr->e_ehsize = sizeof(Elf_Ehdr); 1507 ehdr->e_phentsize = sizeof(Elf_Phdr); 1508 ehdr->e_phnum = numsegs + 1; 1509 ehdr->e_shentsize = sizeof(Elf_Shdr); 1510 ehdr->e_shnum = 0; 1511 ehdr->e_shstrndx = SHN_UNDEF; 1512 1513 /* 1514 * Fill in the program header entries. 1515 */ 1516 phdr = (Elf_Phdr *)((char *)dst + phoff); 1517 1518 /* The note segement. */ 1519 phdr->p_type = PT_NOTE; 1520 phdr->p_offset = noteoff; 1521 phdr->p_vaddr = 0; 1522 phdr->p_paddr = 0; 1523 phdr->p_filesz = notesz; 1524 phdr->p_memsz = 0; 1525 phdr->p_flags = 0; 1526 phdr->p_align = 0; 1527 phdr++; 1528 1529 /* All the writable segments from the program. */ 1530 phc.phdr = phdr; 1531 phc.offset = *off; 1532 each_writable_segment(td, cb_put_phdr, &phc); 1533 } 1534 } 1535 1536 static void 1537 __elfN(putnote)(void *dst, size_t *off, const char *name, int type, 1538 const void *desc, size_t descsz) 1539 { 1540 Elf_Note note; 1541 1542 note.n_namesz = strlen(name) + 1; 1543 note.n_descsz = descsz; 1544 note.n_type = type; 1545 if (dst != NULL) 1546 bcopy(¬e, (char *)dst + *off, sizeof note); 1547 *off += sizeof note; 1548 if (dst != NULL) 1549 bcopy(name, (char *)dst + *off, note.n_namesz); 1550 *off += roundup2(note.n_namesz, sizeof(Elf_Size)); 1551 if (dst != NULL) 1552 bcopy(desc, (char *)dst + *off, note.n_descsz); 1553 *off += roundup2(note.n_descsz, sizeof(Elf_Size)); 1554 } 1555 1556 static boolean_t 1557 __elfN(parse_notes)(struct image_params *imgp, Elf_Brandnote *checknote, 1558 int32_t *osrel, const Elf_Phdr *pnote) 1559 { 1560 const Elf_Note *note, *note0, *note_end; 1561 const char *note_name; 1562 int i; 1563 1564 if (pnote == NULL || pnote->p_offset >= PAGE_SIZE || 1565 pnote->p_filesz > PAGE_SIZE || 1566 pnote->p_offset + pnote->p_filesz >= PAGE_SIZE) 1567 return (FALSE); 1568 1569 note = note0 = (const Elf_Note *)(imgp->image_header + pnote->p_offset); 1570 note_end = (const Elf_Note *)(imgp->image_header + 1571 pnote->p_offset + pnote->p_filesz); 1572 for (i = 0; i < 100 && note >= note0 && note < note_end; i++) { 1573 if (!aligned(note, Elf32_Addr) || (const char *)note_end - 1574 (const char *)note < sizeof(Elf_Note)) 1575 return (FALSE); 1576 if (note->n_namesz != checknote->hdr.n_namesz || 1577 note->n_descsz != checknote->hdr.n_descsz || 1578 note->n_type != checknote->hdr.n_type) 1579 goto nextnote; 1580 note_name = (const char *)(note + 1); 1581 if (note_name + checknote->hdr.n_namesz >= 1582 (const char *)note_end || strncmp(checknote->vendor, 1583 note_name, checknote->hdr.n_namesz) != 0) 1584 goto nextnote; 1585 1586 /* 1587 * Fetch the osreldate for binary 1588 * from the ELF OSABI-note if necessary. 1589 */ 1590 if ((checknote->flags & BN_TRANSLATE_OSREL) != 0 && 1591 checknote->trans_osrel != NULL) 1592 return (checknote->trans_osrel(note, osrel)); 1593 return (TRUE); 1594 1595 nextnote: 1596 note = (const Elf_Note *)((const char *)(note + 1) + 1597 roundup2(note->n_namesz, sizeof(Elf32_Addr)) + 1598 roundup2(note->n_descsz, sizeof(Elf32_Addr))); 1599 } 1600 1601 return (FALSE); 1602 } 1603 1604 /* 1605 * Try to find the appropriate ABI-note section for checknote, 1606 * fetch the osreldate for binary from the ELF OSABI-note. Only the 1607 * first page of the image is searched, the same as for headers. 1608 */ 1609 static boolean_t 1610 __elfN(check_note)(struct image_params *imgp, Elf_Brandnote *checknote, 1611 int32_t *osrel) 1612 { 1613 const Elf_Phdr *phdr; 1614 const Elf_Ehdr *hdr; 1615 int i; 1616 1617 hdr = (const Elf_Ehdr *)imgp->image_header; 1618 phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff); 1619 1620 for (i = 0; i < hdr->e_phnum; i++) { 1621 if (phdr[i].p_type == PT_NOTE && 1622 __elfN(parse_notes)(imgp, checknote, osrel, &phdr[i])) 1623 return (TRUE); 1624 } 1625 return (FALSE); 1626 1627 } 1628 1629 /* 1630 * Tell kern_execve.c about it, with a little help from the linker. 1631 */ 1632 static struct execsw __elfN(execsw) = { 1633 __CONCAT(exec_, __elfN(imgact)), 1634 __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) 1635 }; 1636 EXEC_SET(__CONCAT(elf, __ELF_WORD_SIZE), __elfN(execsw)); 1637 1638 #ifdef COMPRESS_USER_CORES 1639 /* 1640 * Compress and write out a core segment for a user process. 1641 * 1642 * 'inbuf' is the starting address of a VM segment in the process' address 1643 * space that is to be compressed and written out to the core file. 'dest_buf' 1644 * is a buffer in the kernel's address space. The segment is copied from 1645 * 'inbuf' to 'dest_buf' first before being processed by the compression 1646 * routine gzwrite(). This copying is necessary because the content of the VM 1647 * segment may change between the compression pass and the crc-computation pass 1648 * in gzwrite(). This is because realtime threads may preempt the UNIX kernel. 1649 */ 1650 static int 1651 compress_core (gzFile file, char *inbuf, char *dest_buf, unsigned int len, 1652 struct thread *td) 1653 { 1654 int len_compressed; 1655 int error = 0; 1656 unsigned int chunk_len; 1657 1658 while (len) { 1659 chunk_len = (len > CORE_BUF_SIZE) ? CORE_BUF_SIZE : len; 1660 copyin(inbuf, dest_buf, chunk_len); 1661 len_compressed = gzwrite(file, dest_buf, chunk_len); 1662 1663 EVENTHANDLER_INVOKE(app_coredump_progress, td, len_compressed); 1664 1665 if ((unsigned int)len_compressed != chunk_len) { 1666 log(LOG_WARNING, 1667 "compress_core: length mismatch (0x%x returned, " 1668 "0x%x expected)\n", len_compressed, chunk_len); 1669 EVENTHANDLER_INVOKE(app_coredump_error, td, 1670 "compress_core: length mismatch %x -> %x", 1671 chunk_len, len_compressed); 1672 error = EFAULT; 1673 break; 1674 } 1675 inbuf += chunk_len; 1676 len -= chunk_len; 1677 maybe_yield(); 1678 } 1679 1680 return (error); 1681 } 1682 #endif /* COMPRESS_USER_CORES */ 1683 1684 static vm_prot_t 1685 __elfN(trans_prot)(Elf_Word flags) 1686 { 1687 vm_prot_t prot; 1688 1689 prot = 0; 1690 if (flags & PF_X) 1691 prot |= VM_PROT_EXECUTE; 1692 if (flags & PF_W) 1693 prot |= VM_PROT_WRITE; 1694 if (flags & PF_R) 1695 prot |= VM_PROT_READ; 1696 #if __ELF_WORD_SIZE == 32 1697 #if defined(__amd64__) || defined(__ia64__) 1698 if (i386_read_exec && (flags & PF_R)) 1699 prot |= VM_PROT_EXECUTE; 1700 #endif 1701 #endif 1702 return (prot); 1703 } 1704 1705 static Elf_Word 1706 __elfN(untrans_prot)(vm_prot_t prot) 1707 { 1708 Elf_Word flags; 1709 1710 flags = 0; 1711 if (prot & VM_PROT_EXECUTE) 1712 flags |= PF_X; 1713 if (prot & VM_PROT_READ) 1714 flags |= PF_R; 1715 if (prot & VM_PROT_WRITE) 1716 flags |= PF_W; 1717 return (flags); 1718 }
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