1 /*- 2 * Copyright (c) 2000 David O'Brien 3 * Copyright (c) 1995-1996 S�ren Schmidt 4 * Copyright (c) 1996 Peter Wemm 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer 12 * in this position and unchanged. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. The name of the author may not be used to endorse or promote products 17 * derived from this software without specific prior written permission 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #include <sys/cdefs.h> 32 __FBSDID("$FreeBSD$"); 33 34 #include "opt_capsicum.h" 35 #include "opt_compat.h" 36 #include "opt_core.h" 37 38 #include <sys/param.h> 39 #include <sys/capability.h> 40 #include <sys/exec.h> 41 #include <sys/fcntl.h> 42 #include <sys/imgact.h> 43 #include <sys/imgact_elf.h> 44 #include <sys/kernel.h> 45 #include <sys/lock.h> 46 #include <sys/malloc.h> 47 #include <sys/mount.h> 48 #include <sys/mutex.h> 49 #include <sys/mman.h> 50 #include <sys/namei.h> 51 #include <sys/pioctl.h> 52 #include <sys/proc.h> 53 #include <sys/procfs.h> 54 #include <sys/racct.h> 55 #include <sys/resourcevar.h> 56 #include <sys/sf_buf.h> 57 #include <sys/smp.h> 58 #include <sys/systm.h> 59 #include <sys/signalvar.h> 60 #include <sys/stat.h> 61 #include <sys/sx.h> 62 #include <sys/syscall.h> 63 #include <sys/sysctl.h> 64 #include <sys/sysent.h> 65 #include <sys/vnode.h> 66 #include <sys/syslog.h> 67 #include <sys/eventhandler.h> 68 69 #include <net/zlib.h> 70 71 #include <vm/vm.h> 72 #include <vm/vm_kern.h> 73 #include <vm/vm_param.h> 74 #include <vm/pmap.h> 75 #include <vm/vm_map.h> 76 #include <vm/vm_object.h> 77 #include <vm/vm_extern.h> 78 79 #include <machine/elf.h> 80 #include <machine/md_var.h> 81 82 #define OLD_EI_BRAND 8 83 84 static int __elfN(check_header)(const Elf_Ehdr *hdr); 85 static Elf_Brandinfo *__elfN(get_brandinfo)(struct image_params *imgp, 86 const char *interp, int32_t *osrel); 87 static int __elfN(load_file)(struct proc *p, const char *file, u_long *addr, 88 u_long *entry, size_t pagesize); 89 static int __elfN(load_section)(struct 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 static int __elfN(nxstack) = 0; 122 SYSCTL_INT(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO, 123 nxstack, CTLFLAG_RW, &__elfN(nxstack), 0, 124 __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) ": enable non-executable stack"); 125 126 static Elf_Brandinfo *elf_brand_list[MAX_BRANDS]; 127 128 #define trunc_page_ps(va, ps) ((va) & ~(ps - 1)) 129 #define round_page_ps(va, ps) (((va) + (ps - 1)) & ~(ps - 1)) 130 #define aligned(a, t) (trunc_page_ps((u_long)(a), sizeof(t)) == (u_long)(a)) 131 132 static const char FREEBSD_ABI_VENDOR[] = "FreeBSD"; 133 134 Elf_Brandnote __elfN(freebsd_brandnote) = { 135 .hdr.n_namesz = sizeof(FREEBSD_ABI_VENDOR), 136 .hdr.n_descsz = sizeof(int32_t), 137 .hdr.n_type = 1, 138 .vendor = FREEBSD_ABI_VENDOR, 139 .flags = BN_TRANSLATE_OSREL, 140 .trans_osrel = __elfN(freebsd_trans_osrel) 141 }; 142 143 static boolean_t 144 __elfN(freebsd_trans_osrel)(const Elf_Note *note, int32_t *osrel) 145 { 146 uintptr_t p; 147 148 p = (uintptr_t)(note + 1); 149 p += roundup2(note->n_namesz, sizeof(Elf32_Addr)); 150 *osrel = *(const int32_t *)(p); 151 152 return (TRUE); 153 } 154 155 static const char GNU_ABI_VENDOR[] = "GNU"; 156 static int GNU_KFREEBSD_ABI_DESC = 3; 157 158 Elf_Brandnote __elfN(kfreebsd_brandnote) = { 159 .hdr.n_namesz = sizeof(GNU_ABI_VENDOR), 160 .hdr.n_descsz = 16, /* XXX at least 16 */ 161 .hdr.n_type = 1, 162 .vendor = GNU_ABI_VENDOR, 163 .flags = BN_TRANSLATE_OSREL, 164 .trans_osrel = kfreebsd_trans_osrel 165 }; 166 167 static boolean_t 168 kfreebsd_trans_osrel(const Elf_Note *note, int32_t *osrel) 169 { 170 const Elf32_Word *desc; 171 uintptr_t p; 172 173 p = (uintptr_t)(note + 1); 174 p += roundup2(note->n_namesz, sizeof(Elf32_Addr)); 175 176 desc = (const Elf32_Word *)p; 177 if (desc[0] != GNU_KFREEBSD_ABI_DESC) 178 return (FALSE); 179 180 /* 181 * Debian GNU/kFreeBSD embed the earliest compatible kernel version 182 * (__FreeBSD_version: <major><two digit minor>Rxx) in the LSB way. 183 */ 184 *osrel = desc[1] * 100000 + desc[2] * 1000 + desc[3]; 185 186 return (TRUE); 187 } 188 189 int 190 __elfN(insert_brand_entry)(Elf_Brandinfo *entry) 191 { 192 int i; 193 194 for (i = 0; i < MAX_BRANDS; i++) { 195 if (elf_brand_list[i] == NULL) { 196 elf_brand_list[i] = entry; 197 break; 198 } 199 } 200 if (i == MAX_BRANDS) { 201 printf("WARNING: %s: could not insert brandinfo entry: %p\n", 202 __func__, entry); 203 return (-1); 204 } 205 return (0); 206 } 207 208 int 209 __elfN(remove_brand_entry)(Elf_Brandinfo *entry) 210 { 211 int i; 212 213 for (i = 0; i < MAX_BRANDS; i++) { 214 if (elf_brand_list[i] == entry) { 215 elf_brand_list[i] = NULL; 216 break; 217 } 218 } 219 if (i == MAX_BRANDS) 220 return (-1); 221 return (0); 222 } 223 224 int 225 __elfN(brand_inuse)(Elf_Brandinfo *entry) 226 { 227 struct proc *p; 228 int rval = FALSE; 229 230 sx_slock(&allproc_lock); 231 FOREACH_PROC_IN_SYSTEM(p) { 232 if (p->p_sysent == entry->sysvec) { 233 rval = TRUE; 234 break; 235 } 236 } 237 sx_sunlock(&allproc_lock); 238 239 return (rval); 240 } 241 242 static Elf_Brandinfo * 243 __elfN(get_brandinfo)(struct image_params *imgp, const char *interp, 244 int32_t *osrel) 245 { 246 const Elf_Ehdr *hdr = (const Elf_Ehdr *)imgp->image_header; 247 Elf_Brandinfo *bi; 248 boolean_t ret; 249 int i; 250 251 /* 252 * We support four types of branding -- (1) the ELF EI_OSABI field 253 * that SCO added to the ELF spec, (2) FreeBSD 3.x's traditional string 254 * branding w/in the ELF header, (3) path of the `interp_path' 255 * field, and (4) the ".note.ABI-tag" ELF section. 256 */ 257 258 /* Look for an ".note.ABI-tag" ELF section */ 259 for (i = 0; i < MAX_BRANDS; i++) { 260 bi = elf_brand_list[i]; 261 if (bi == NULL) 262 continue; 263 if (hdr->e_machine == bi->machine && (bi->flags & 264 (BI_BRAND_NOTE|BI_BRAND_NOTE_MANDATORY)) != 0) { 265 ret = __elfN(check_note)(imgp, bi->brand_note, osrel); 266 if (ret) 267 return (bi); 268 } 269 } 270 271 /* If the executable has a brand, search for it in the brand list. */ 272 for (i = 0; i < MAX_BRANDS; i++) { 273 bi = elf_brand_list[i]; 274 if (bi == NULL || bi->flags & BI_BRAND_NOTE_MANDATORY) 275 continue; 276 if (hdr->e_machine == bi->machine && 277 (hdr->e_ident[EI_OSABI] == bi->brand || 278 strncmp((const char *)&hdr->e_ident[OLD_EI_BRAND], 279 bi->compat_3_brand, strlen(bi->compat_3_brand)) == 0)) 280 return (bi); 281 } 282 283 /* Lacking a known brand, search for a recognized interpreter. */ 284 if (interp != NULL) { 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 strcmp(interp, bi->interp_path) == 0) 291 return (bi); 292 } 293 } 294 295 /* Lacking a recognized interpreter, try the default brand */ 296 for (i = 0; i < MAX_BRANDS; i++) { 297 bi = elf_brand_list[i]; 298 if (bi == NULL || bi->flags & BI_BRAND_NOTE_MANDATORY) 299 continue; 300 if (hdr->e_machine == bi->machine && 301 __elfN(fallback_brand) == bi->brand) 302 return (bi); 303 } 304 return (NULL); 305 } 306 307 static int 308 __elfN(check_header)(const Elf_Ehdr *hdr) 309 { 310 Elf_Brandinfo *bi; 311 int i; 312 313 if (!IS_ELF(*hdr) || 314 hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS || 315 hdr->e_ident[EI_DATA] != ELF_TARG_DATA || 316 hdr->e_ident[EI_VERSION] != EV_CURRENT || 317 hdr->e_phentsize != sizeof(Elf_Phdr) || 318 hdr->e_version != ELF_TARG_VER) 319 return (ENOEXEC); 320 321 /* 322 * Make sure we have at least one brand for this machine. 323 */ 324 325 for (i = 0; i < MAX_BRANDS; i++) { 326 bi = elf_brand_list[i]; 327 if (bi != NULL && bi->machine == hdr->e_machine) 328 break; 329 } 330 if (i == MAX_BRANDS) 331 return (ENOEXEC); 332 333 return (0); 334 } 335 336 static int 337 __elfN(map_partial)(vm_map_t map, vm_object_t object, vm_ooffset_t offset, 338 vm_offset_t start, vm_offset_t end, vm_prot_t prot) 339 { 340 struct sf_buf *sf; 341 int error; 342 vm_offset_t off; 343 344 /* 345 * Create the page if it doesn't exist yet. Ignore errors. 346 */ 347 vm_map_lock(map); 348 vm_map_insert(map, NULL, 0, trunc_page(start), round_page(end), 349 VM_PROT_ALL, VM_PROT_ALL, 0); 350 vm_map_unlock(map); 351 352 /* 353 * Find the page from the underlying object. 354 */ 355 if (object) { 356 sf = vm_imgact_map_page(object, offset); 357 if (sf == NULL) 358 return (KERN_FAILURE); 359 off = offset - trunc_page(offset); 360 error = copyout((caddr_t)sf_buf_kva(sf) + off, (caddr_t)start, 361 end - start); 362 vm_imgact_unmap_page(sf); 363 if (error) { 364 return (KERN_FAILURE); 365 } 366 } 367 368 return (KERN_SUCCESS); 369 } 370 371 static int 372 __elfN(map_insert)(vm_map_t map, vm_object_t object, vm_ooffset_t offset, 373 vm_offset_t start, vm_offset_t end, vm_prot_t prot, int cow) 374 { 375 struct sf_buf *sf; 376 vm_offset_t off; 377 vm_size_t sz; 378 int error, rv; 379 380 if (start != trunc_page(start)) { 381 rv = __elfN(map_partial)(map, object, offset, start, 382 round_page(start), prot); 383 if (rv) 384 return (rv); 385 offset += round_page(start) - start; 386 start = round_page(start); 387 } 388 if (end != round_page(end)) { 389 rv = __elfN(map_partial)(map, object, offset + 390 trunc_page(end) - start, trunc_page(end), end, prot); 391 if (rv) 392 return (rv); 393 end = trunc_page(end); 394 } 395 if (end > start) { 396 if (offset & PAGE_MASK) { 397 /* 398 * The mapping is not page aligned. This means we have 399 * to copy the data. Sigh. 400 */ 401 rv = vm_map_find(map, NULL, 0, &start, end - start, 402 FALSE, prot | VM_PROT_WRITE, VM_PROT_ALL, 0); 403 if (rv) 404 return (rv); 405 if (object == NULL) 406 return (KERN_SUCCESS); 407 for (; start < end; start += sz) { 408 sf = vm_imgact_map_page(object, offset); 409 if (sf == NULL) 410 return (KERN_FAILURE); 411 off = offset - trunc_page(offset); 412 sz = end - start; 413 if (sz > PAGE_SIZE - off) 414 sz = PAGE_SIZE - off; 415 error = copyout((caddr_t)sf_buf_kva(sf) + off, 416 (caddr_t)start, sz); 417 vm_imgact_unmap_page(sf); 418 if (error) { 419 return (KERN_FAILURE); 420 } 421 offset += sz; 422 } 423 rv = KERN_SUCCESS; 424 } else { 425 vm_object_reference(object); 426 vm_map_lock(map); 427 rv = vm_map_insert(map, object, offset, start, end, 428 prot, VM_PROT_ALL, cow); 429 vm_map_unlock(map); 430 if (rv != KERN_SUCCESS) 431 vm_object_deallocate(object); 432 } 433 return (rv); 434 } else { 435 return (KERN_SUCCESS); 436 } 437 } 438 439 static int 440 __elfN(load_section)(struct vmspace *vmspace, 441 vm_object_t object, vm_offset_t offset, 442 caddr_t vmaddr, size_t memsz, size_t filsz, vm_prot_t prot, 443 size_t pagesize) 444 { 445 struct sf_buf *sf; 446 size_t map_len; 447 vm_offset_t map_addr; 448 int error, rv, cow; 449 size_t copy_len; 450 vm_offset_t file_addr; 451 452 /* 453 * It's necessary to fail if the filsz + offset taken from the 454 * header is greater than the actual file pager object's size. 455 * If we were to allow this, then the vm_map_find() below would 456 * walk right off the end of the file object and into the ether. 457 * 458 * While I'm here, might as well check for something else that 459 * is invalid: filsz cannot be greater than memsz. 460 */ 461 if ((off_t)filsz + offset > object->un_pager.vnp.vnp_size || 462 filsz > memsz) { 463 uprintf("elf_load_section: truncated ELF file\n"); 464 return (ENOEXEC); 465 } 466 467 map_addr = trunc_page_ps((vm_offset_t)vmaddr, pagesize); 468 file_addr = trunc_page_ps(offset, pagesize); 469 470 /* 471 * We have two choices. We can either clear the data in the last page 472 * of an oversized mapping, or we can start the anon mapping a page 473 * early and copy the initialized data into that first page. We 474 * choose the second.. 475 */ 476 if (memsz > filsz) 477 map_len = trunc_page_ps(offset + filsz, pagesize) - file_addr; 478 else 479 map_len = round_page_ps(offset + filsz, pagesize) - file_addr; 480 481 if (map_len != 0) { 482 /* cow flags: don't dump readonly sections in core */ 483 cow = MAP_COPY_ON_WRITE | MAP_PREFAULT | 484 (prot & VM_PROT_WRITE ? 0 : MAP_DISABLE_COREDUMP); 485 486 rv = __elfN(map_insert)(&vmspace->vm_map, 487 object, 488 file_addr, /* file offset */ 489 map_addr, /* virtual start */ 490 map_addr + map_len,/* virtual end */ 491 prot, 492 cow); 493 if (rv != KERN_SUCCESS) 494 return (EINVAL); 495 496 /* we can stop now if we've covered it all */ 497 if (memsz == filsz) { 498 return (0); 499 } 500 } 501 502 503 /* 504 * We have to get the remaining bit of the file into the first part 505 * of the oversized map segment. This is normally because the .data 506 * segment in the file is extended to provide bss. It's a neat idea 507 * to try and save a page, but it's a pain in the behind to implement. 508 */ 509 copy_len = (offset + filsz) - trunc_page_ps(offset + filsz, pagesize); 510 map_addr = trunc_page_ps((vm_offset_t)vmaddr + filsz, pagesize); 511 map_len = round_page_ps((vm_offset_t)vmaddr + memsz, pagesize) - 512 map_addr; 513 514 /* This had damn well better be true! */ 515 if (map_len != 0) { 516 rv = __elfN(map_insert)(&vmspace->vm_map, NULL, 0, map_addr, 517 map_addr + map_len, VM_PROT_ALL, 0); 518 if (rv != KERN_SUCCESS) { 519 return (EINVAL); 520 } 521 } 522 523 if (copy_len != 0) { 524 vm_offset_t off; 525 526 sf = vm_imgact_map_page(object, offset + filsz); 527 if (sf == NULL) 528 return (EIO); 529 530 /* send the page fragment to user space */ 531 off = trunc_page_ps(offset + filsz, pagesize) - 532 trunc_page(offset + filsz); 533 error = copyout((caddr_t)sf_buf_kva(sf) + off, 534 (caddr_t)map_addr, copy_len); 535 vm_imgact_unmap_page(sf); 536 if (error) { 537 return (error); 538 } 539 } 540 541 /* 542 * set it to the specified protection. 543 * XXX had better undo the damage from pasting over the cracks here! 544 */ 545 vm_map_protect(&vmspace->vm_map, trunc_page(map_addr), 546 round_page(map_addr + map_len), prot, FALSE); 547 548 return (0); 549 } 550 551 /* 552 * Load the file "file" into memory. It may be either a shared object 553 * or an executable. 554 * 555 * The "addr" reference parameter is in/out. On entry, it specifies 556 * the address where a shared object should be loaded. If the file is 557 * an executable, this value is ignored. On exit, "addr" specifies 558 * where the file was actually loaded. 559 * 560 * The "entry" reference parameter is out only. On exit, it specifies 561 * the entry point for the loaded file. 562 */ 563 static int 564 __elfN(load_file)(struct proc *p, const char *file, u_long *addr, 565 u_long *entry, size_t pagesize) 566 { 567 struct { 568 struct nameidata nd; 569 struct vattr attr; 570 struct image_params image_params; 571 } *tempdata; 572 const Elf_Ehdr *hdr = NULL; 573 const Elf_Phdr *phdr = NULL; 574 struct nameidata *nd; 575 struct vmspace *vmspace = p->p_vmspace; 576 struct vattr *attr; 577 struct image_params *imgp; 578 vm_prot_t prot; 579 u_long rbase; 580 u_long base_addr = 0; 581 int vfslocked, error, i, numsegs; 582 583 #ifdef CAPABILITY_MODE 584 /* 585 * XXXJA: This check can go away once we are sufficiently confident 586 * that the checks in namei() are correct. 587 */ 588 if (IN_CAPABILITY_MODE(curthread)) 589 return (ECAPMODE); 590 #endif 591 592 tempdata = malloc(sizeof(*tempdata), M_TEMP, M_WAITOK); 593 nd = &tempdata->nd; 594 attr = &tempdata->attr; 595 imgp = &tempdata->image_params; 596 597 /* 598 * Initialize part of the common data 599 */ 600 imgp->proc = p; 601 imgp->attr = attr; 602 imgp->firstpage = NULL; 603 imgp->image_header = NULL; 604 imgp->object = NULL; 605 imgp->execlabel = NULL; 606 607 NDINIT(nd, LOOKUP, MPSAFE|LOCKLEAF|FOLLOW, UIO_SYSSPACE, file, 608 curthread); 609 vfslocked = 0; 610 if ((error = namei(nd)) != 0) { 611 nd->ni_vp = NULL; 612 goto fail; 613 } 614 vfslocked = NDHASGIANT(nd); 615 NDFREE(nd, NDF_ONLY_PNBUF); 616 imgp->vp = nd->ni_vp; 617 618 /* 619 * Check permissions, modes, uid, etc on the file, and "open" it. 620 */ 621 error = exec_check_permissions(imgp); 622 if (error) 623 goto fail; 624 625 error = exec_map_first_page(imgp); 626 if (error) 627 goto fail; 628 629 /* 630 * Also make certain that the interpreter stays the same, so set 631 * its VV_TEXT flag, too. 632 */ 633 nd->ni_vp->v_vflag |= VV_TEXT; 634 635 imgp->object = nd->ni_vp->v_object; 636 637 hdr = (const Elf_Ehdr *)imgp->image_header; 638 if ((error = __elfN(check_header)(hdr)) != 0) 639 goto fail; 640 if (hdr->e_type == ET_DYN) 641 rbase = *addr; 642 else if (hdr->e_type == ET_EXEC) 643 rbase = 0; 644 else { 645 error = ENOEXEC; 646 goto fail; 647 } 648 649 /* Only support headers that fit within first page for now */ 650 /* (multiplication of two Elf_Half fields will not overflow) */ 651 if ((hdr->e_phoff > PAGE_SIZE) || 652 (hdr->e_phentsize * hdr->e_phnum) > PAGE_SIZE - hdr->e_phoff) { 653 error = ENOEXEC; 654 goto fail; 655 } 656 657 phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff); 658 if (!aligned(phdr, Elf_Addr)) { 659 error = ENOEXEC; 660 goto fail; 661 } 662 663 for (i = 0, numsegs = 0; i < hdr->e_phnum; i++) { 664 if (phdr[i].p_type == PT_LOAD && phdr[i].p_memsz != 0) { 665 /* Loadable segment */ 666 prot = __elfN(trans_prot)(phdr[i].p_flags); 667 if ((error = __elfN(load_section)(vmspace, 668 imgp->object, phdr[i].p_offset, 669 (caddr_t)(uintptr_t)phdr[i].p_vaddr + rbase, 670 phdr[i].p_memsz, phdr[i].p_filesz, prot, 671 pagesize)) != 0) 672 goto fail; 673 /* 674 * Establish the base address if this is the 675 * first segment. 676 */ 677 if (numsegs == 0) 678 base_addr = trunc_page(phdr[i].p_vaddr + 679 rbase); 680 numsegs++; 681 } 682 } 683 *addr = base_addr; 684 *entry = (unsigned long)hdr->e_entry + rbase; 685 686 fail: 687 if (imgp->firstpage) 688 exec_unmap_first_page(imgp); 689 690 if (nd->ni_vp) 691 vput(nd->ni_vp); 692 693 VFS_UNLOCK_GIANT(vfslocked); 694 free(tempdata, M_TEMP); 695 696 return (error); 697 } 698 699 static int 700 __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp) 701 { 702 const Elf_Ehdr *hdr = (const Elf_Ehdr *)imgp->image_header; 703 const Elf_Phdr *phdr; 704 Elf_Auxargs *elf_auxargs; 705 struct vmspace *vmspace; 706 vm_prot_t prot; 707 u_long text_size = 0, data_size = 0, total_size = 0; 708 u_long text_addr = 0, data_addr = 0; 709 u_long seg_size, seg_addr; 710 u_long addr, baddr, et_dyn_addr, entry = 0, proghdr = 0; 711 int32_t osrel = 0; 712 int error = 0, i, n; 713 const char *interp = NULL, *newinterp = NULL; 714 Elf_Brandinfo *brand_info; 715 char *path; 716 struct sysentvec *sv; 717 718 /* 719 * Do we have a valid ELF header ? 720 * 721 * Only allow ET_EXEC & ET_DYN here, reject ET_DYN later 722 * if particular brand doesn't support it. 723 */ 724 if (__elfN(check_header)(hdr) != 0 || 725 (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN)) 726 return (-1); 727 728 /* 729 * From here on down, we return an errno, not -1, as we've 730 * detected an ELF file. 731 */ 732 733 if ((hdr->e_phoff > PAGE_SIZE) || 734 (hdr->e_phoff + hdr->e_phentsize * hdr->e_phnum) > PAGE_SIZE) { 735 /* Only support headers in first page for now */ 736 return (ENOEXEC); 737 } 738 phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff); 739 if (!aligned(phdr, Elf_Addr)) 740 return (ENOEXEC); 741 n = 0; 742 baddr = 0; 743 for (i = 0; i < hdr->e_phnum; i++) { 744 switch (phdr[i].p_type) { 745 case PT_LOAD: 746 if (n == 0) 747 baddr = phdr[i].p_vaddr; 748 n++; 749 break; 750 case PT_INTERP: 751 /* Path to interpreter */ 752 if (phdr[i].p_filesz > MAXPATHLEN || 753 phdr[i].p_offset + phdr[i].p_filesz > PAGE_SIZE) 754 return (ENOEXEC); 755 interp = imgp->image_header + phdr[i].p_offset; 756 break; 757 case PT_GNU_STACK: 758 if (__elfN(nxstack)) 759 imgp->stack_prot = 760 __elfN(trans_prot)(phdr[i].p_flags); 761 break; 762 } 763 } 764 765 brand_info = __elfN(get_brandinfo)(imgp, interp, &osrel); 766 if (brand_info == NULL) { 767 uprintf("ELF binary type \"%u\" not known.\n", 768 hdr->e_ident[EI_OSABI]); 769 return (ENOEXEC); 770 } 771 if (hdr->e_type == ET_DYN) { 772 if ((brand_info->flags & BI_CAN_EXEC_DYN) == 0) 773 return (ENOEXEC); 774 /* 775 * Honour the base load address from the dso if it is 776 * non-zero for some reason. 777 */ 778 if (baddr == 0) 779 et_dyn_addr = ET_DYN_LOAD_ADDR; 780 else 781 et_dyn_addr = 0; 782 } else 783 et_dyn_addr = 0; 784 sv = brand_info->sysvec; 785 if (interp != NULL && brand_info->interp_newpath != NULL) 786 newinterp = brand_info->interp_newpath; 787 788 /* 789 * Avoid a possible deadlock if the current address space is destroyed 790 * and that address space maps the locked vnode. In the common case, 791 * the locked vnode's v_usecount is decremented but remains greater 792 * than zero. Consequently, the vnode lock is not needed by vrele(). 793 * However, in cases where the vnode lock is external, such as nullfs, 794 * v_usecount may become zero. 795 */ 796 VOP_UNLOCK(imgp->vp, 0); 797 798 error = exec_new_vmspace(imgp, sv); 799 imgp->proc->p_sysent = sv; 800 801 vn_lock(imgp->vp, LK_EXCLUSIVE | LK_RETRY); 802 if (error) 803 return (error); 804 805 vmspace = imgp->proc->p_vmspace; 806 807 for (i = 0; i < hdr->e_phnum; i++) { 808 switch (phdr[i].p_type) { 809 case PT_LOAD: /* Loadable segment */ 810 if (phdr[i].p_memsz == 0) 811 break; 812 prot = __elfN(trans_prot)(phdr[i].p_flags); 813 814 #if defined(__ia64__) && __ELF_WORD_SIZE == 32 && defined(IA32_ME_HARDER) 815 /* 816 * Some x86 binaries assume read == executable, 817 * notably the M3 runtime and therefore cvsup 818 */ 819 if (prot & VM_PROT_READ) 820 prot |= VM_PROT_EXECUTE; 821 #endif 822 823 if ((error = __elfN(load_section)(vmspace, 824 imgp->object, phdr[i].p_offset, 825 (caddr_t)(uintptr_t)phdr[i].p_vaddr + et_dyn_addr, 826 phdr[i].p_memsz, phdr[i].p_filesz, prot, 827 sv->sv_pagesize)) != 0) 828 return (error); 829 830 /* 831 * If this segment contains the program headers, 832 * remember their virtual address for the AT_PHDR 833 * aux entry. Static binaries don't usually include 834 * a PT_PHDR entry. 835 */ 836 if (phdr[i].p_offset == 0 && 837 hdr->e_phoff + hdr->e_phnum * hdr->e_phentsize 838 <= phdr[i].p_filesz) 839 proghdr = phdr[i].p_vaddr + hdr->e_phoff + 840 et_dyn_addr; 841 842 seg_addr = trunc_page(phdr[i].p_vaddr + et_dyn_addr); 843 seg_size = round_page(phdr[i].p_memsz + 844 phdr[i].p_vaddr + et_dyn_addr - seg_addr); 845 846 /* 847 * Make the largest executable segment the official 848 * text segment and all others data. 849 * 850 * Note that obreak() assumes that data_addr + 851 * data_size == end of data load area, and the ELF 852 * file format expects segments to be sorted by 853 * address. If multiple data segments exist, the 854 * last one will be used. 855 */ 856 857 if (phdr[i].p_flags & PF_X && text_size < seg_size) { 858 text_size = seg_size; 859 text_addr = seg_addr; 860 } else { 861 data_size = seg_size; 862 data_addr = seg_addr; 863 } 864 total_size += seg_size; 865 break; 866 case PT_PHDR: /* Program header table info */ 867 proghdr = phdr[i].p_vaddr + et_dyn_addr; 868 break; 869 default: 870 break; 871 } 872 } 873 874 if (data_addr == 0 && data_size == 0) { 875 data_addr = text_addr; 876 data_size = text_size; 877 } 878 879 entry = (u_long)hdr->e_entry + et_dyn_addr; 880 881 /* 882 * Check limits. It should be safe to check the 883 * limits after loading the segments since we do 884 * not actually fault in all the segments pages. 885 */ 886 PROC_LOCK(imgp->proc); 887 if (data_size > lim_cur(imgp->proc, RLIMIT_DATA) || 888 text_size > maxtsiz || 889 total_size > lim_cur(imgp->proc, RLIMIT_VMEM) || 890 racct_set(imgp->proc, RACCT_DATA, data_size) != 0 || 891 racct_set(imgp->proc, RACCT_VMEM, total_size) != 0) { 892 PROC_UNLOCK(imgp->proc); 893 return (ENOMEM); 894 } 895 896 vmspace->vm_tsize = text_size >> PAGE_SHIFT; 897 vmspace->vm_taddr = (caddr_t)(uintptr_t)text_addr; 898 vmspace->vm_dsize = data_size >> PAGE_SHIFT; 899 vmspace->vm_daddr = (caddr_t)(uintptr_t)data_addr; 900 901 /* 902 * We load the dynamic linker where a userland call 903 * to mmap(0, ...) would put it. The rationale behind this 904 * calculation is that it leaves room for the heap to grow to 905 * its maximum allowed size. 906 */ 907 addr = round_page((vm_offset_t)imgp->proc->p_vmspace->vm_daddr + 908 lim_max(imgp->proc, RLIMIT_DATA)); 909 PROC_UNLOCK(imgp->proc); 910 911 imgp->entry_addr = entry; 912 913 if (interp != NULL) { 914 int have_interp = FALSE; 915 VOP_UNLOCK(imgp->vp, 0); 916 if (brand_info->emul_path != NULL && 917 brand_info->emul_path[0] != '\0') { 918 path = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 919 snprintf(path, MAXPATHLEN, "%s%s", 920 brand_info->emul_path, interp); 921 error = __elfN(load_file)(imgp->proc, path, &addr, 922 &imgp->entry_addr, sv->sv_pagesize); 923 free(path, M_TEMP); 924 if (error == 0) 925 have_interp = TRUE; 926 } 927 if (!have_interp && newinterp != NULL) { 928 error = __elfN(load_file)(imgp->proc, newinterp, &addr, 929 &imgp->entry_addr, sv->sv_pagesize); 930 if (error == 0) 931 have_interp = TRUE; 932 } 933 if (!have_interp) { 934 error = __elfN(load_file)(imgp->proc, interp, &addr, 935 &imgp->entry_addr, sv->sv_pagesize); 936 } 937 vn_lock(imgp->vp, LK_EXCLUSIVE | LK_RETRY); 938 if (error != 0) { 939 uprintf("ELF interpreter %s not found\n", interp); 940 return (error); 941 } 942 } else 943 addr = et_dyn_addr; 944 945 /* 946 * Construct auxargs table (used by the fixup routine) 947 */ 948 elf_auxargs = malloc(sizeof(Elf_Auxargs), M_TEMP, M_WAITOK); 949 elf_auxargs->execfd = -1; 950 elf_auxargs->phdr = proghdr; 951 elf_auxargs->phent = hdr->e_phentsize; 952 elf_auxargs->phnum = hdr->e_phnum; 953 elf_auxargs->pagesz = PAGE_SIZE; 954 elf_auxargs->base = addr; 955 elf_auxargs->flags = 0; 956 elf_auxargs->entry = entry; 957 958 imgp->auxargs = elf_auxargs; 959 imgp->interpreted = 0; 960 imgp->reloc_base = addr; 961 imgp->proc->p_osrel = osrel; 962 963 return (error); 964 } 965 966 #define suword __CONCAT(suword, __ELF_WORD_SIZE) 967 968 int 969 __elfN(freebsd_fixup)(register_t **stack_base, struct image_params *imgp) 970 { 971 Elf_Auxargs *args = (Elf_Auxargs *)imgp->auxargs; 972 Elf_Addr *base; 973 Elf_Addr *pos; 974 975 base = (Elf_Addr *)*stack_base; 976 pos = base + (imgp->args->argc + imgp->args->envc + 2); 977 978 if (args->execfd != -1) 979 AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd); 980 AUXARGS_ENTRY(pos, AT_PHDR, args->phdr); 981 AUXARGS_ENTRY(pos, AT_PHENT, args->phent); 982 AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum); 983 AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz); 984 AUXARGS_ENTRY(pos, AT_FLAGS, args->flags); 985 AUXARGS_ENTRY(pos, AT_ENTRY, args->entry); 986 AUXARGS_ENTRY(pos, AT_BASE, args->base); 987 if (imgp->execpathp != 0) 988 AUXARGS_ENTRY(pos, AT_EXECPATH, imgp->execpathp); 989 AUXARGS_ENTRY(pos, AT_OSRELDATE, osreldate); 990 if (imgp->canary != 0) { 991 AUXARGS_ENTRY(pos, AT_CANARY, imgp->canary); 992 AUXARGS_ENTRY(pos, AT_CANARYLEN, imgp->canarylen); 993 } 994 AUXARGS_ENTRY(pos, AT_NCPUS, mp_ncpus); 995 if (imgp->pagesizes != 0) { 996 AUXARGS_ENTRY(pos, AT_PAGESIZES, imgp->pagesizes); 997 AUXARGS_ENTRY(pos, AT_PAGESIZESLEN, imgp->pagesizeslen); 998 } 999 AUXARGS_ENTRY(pos, AT_STACKPROT, imgp->sysent->sv_shared_page_obj 1000 != NULL && imgp->stack_prot != 0 ? imgp->stack_prot : 1001 imgp->sysent->sv_stackprot); 1002 AUXARGS_ENTRY(pos, AT_NULL, 0); 1003 1004 free(imgp->auxargs, M_TEMP); 1005 imgp->auxargs = NULL; 1006 1007 base--; 1008 suword(base, (long)imgp->args->argc); 1009 *stack_base = (register_t *)base; 1010 return (0); 1011 } 1012 1013 /* 1014 * Code for generating ELF core dumps. 1015 */ 1016 1017 typedef void (*segment_callback)(vm_map_entry_t, void *); 1018 1019 /* Closure for cb_put_phdr(). */ 1020 struct phdr_closure { 1021 Elf_Phdr *phdr; /* Program header to fill in */ 1022 Elf_Off offset; /* Offset of segment in core file */ 1023 }; 1024 1025 /* Closure for cb_size_segment(). */ 1026 struct sseg_closure { 1027 int count; /* Count of writable segments. */ 1028 size_t size; /* Total size of all writable segments. */ 1029 }; 1030 1031 static void cb_put_phdr(vm_map_entry_t, void *); 1032 static void cb_size_segment(vm_map_entry_t, void *); 1033 static void each_writable_segment(struct thread *, segment_callback, void *); 1034 static int __elfN(corehdr)(struct thread *, struct vnode *, struct ucred *, 1035 int, void *, size_t, gzFile); 1036 static void __elfN(puthdr)(struct thread *, void *, size_t *, int); 1037 static void __elfN(putnote)(void *, size_t *, const char *, int, 1038 const void *, size_t); 1039 1040 #ifdef COMPRESS_USER_CORES 1041 extern int compress_user_cores; 1042 extern int compress_user_cores_gzlevel; 1043 #endif 1044 1045 static int 1046 core_output(struct vnode *vp, void *base, size_t len, off_t offset, 1047 struct ucred *active_cred, struct ucred *file_cred, 1048 struct thread *td, char *core_buf, gzFile gzfile) { 1049 1050 int error; 1051 if (gzfile) { 1052 #ifdef COMPRESS_USER_CORES 1053 error = compress_core(gzfile, base, core_buf, len, td); 1054 #else 1055 panic("shouldn't be here"); 1056 #endif 1057 } else { 1058 error = vn_rdwr_inchunks(UIO_WRITE, vp, base, len, offset, 1059 UIO_USERSPACE, IO_UNIT | IO_DIRECT, active_cred, file_cred, 1060 NULL, td); 1061 } 1062 return (error); 1063 } 1064 1065 int 1066 __elfN(coredump)(struct thread *td, struct vnode *vp, off_t limit, int flags) 1067 { 1068 struct ucred *cred = td->td_ucred; 1069 int error = 0; 1070 struct sseg_closure seginfo; 1071 void *hdr; 1072 size_t hdrsize; 1073 1074 gzFile gzfile = Z_NULL; 1075 char *core_buf = NULL; 1076 #ifdef COMPRESS_USER_CORES 1077 char gzopen_flags[8]; 1078 char *p; 1079 int doing_compress = flags & IMGACT_CORE_COMPRESS; 1080 #endif 1081 1082 hdr = NULL; 1083 1084 #ifdef COMPRESS_USER_CORES 1085 if (doing_compress) { 1086 p = gzopen_flags; 1087 *p++ = 'w'; 1088 if (compress_user_cores_gzlevel >= 0 && 1089 compress_user_cores_gzlevel <= 9) 1090 *p++ = '0' + compress_user_cores_gzlevel; 1091 *p = 0; 1092 gzfile = gz_open("", gzopen_flags, vp); 1093 if (gzfile == Z_NULL) { 1094 error = EFAULT; 1095 goto done; 1096 } 1097 core_buf = malloc(CORE_BUF_SIZE, M_TEMP, M_WAITOK | M_ZERO); 1098 if (!core_buf) { 1099 error = ENOMEM; 1100 goto done; 1101 } 1102 } 1103 #endif 1104 1105 /* Size the program segments. */ 1106 seginfo.count = 0; 1107 seginfo.size = 0; 1108 each_writable_segment(td, cb_size_segment, &seginfo); 1109 1110 /* 1111 * Calculate the size of the core file header area by making 1112 * a dry run of generating it. Nothing is written, but the 1113 * size is calculated. 1114 */ 1115 hdrsize = 0; 1116 __elfN(puthdr)(td, (void *)NULL, &hdrsize, seginfo.count); 1117 1118 #ifdef RACCT 1119 PROC_LOCK(td->td_proc); 1120 error = racct_add(td->td_proc, RACCT_CORE, hdrsize + seginfo.size); 1121 PROC_UNLOCK(td->td_proc); 1122 if (error != 0) { 1123 error = EFAULT; 1124 goto done; 1125 } 1126 #endif 1127 if (hdrsize + seginfo.size >= limit) { 1128 error = EFAULT; 1129 goto done; 1130 } 1131 1132 /* 1133 * Allocate memory for building the header, fill it up, 1134 * and write it out. 1135 */ 1136 hdr = malloc(hdrsize, M_TEMP, M_WAITOK); 1137 if (hdr == NULL) { 1138 error = EINVAL; 1139 goto done; 1140 } 1141 error = __elfN(corehdr)(td, vp, cred, seginfo.count, hdr, hdrsize, 1142 gzfile); 1143 1144 /* Write the contents of all of the writable segments. */ 1145 if (error == 0) { 1146 Elf_Phdr *php; 1147 off_t offset; 1148 int i; 1149 1150 php = (Elf_Phdr *)((char *)hdr + sizeof(Elf_Ehdr)) + 1; 1151 offset = hdrsize; 1152 for (i = 0; i < seginfo.count; i++) { 1153 error = core_output(vp, (caddr_t)(uintptr_t)php->p_vaddr, 1154 php->p_filesz, offset, cred, NOCRED, curthread, core_buf, gzfile); 1155 if (error != 0) 1156 break; 1157 offset += php->p_filesz; 1158 php++; 1159 } 1160 } 1161 if (error) { 1162 log(LOG_WARNING, 1163 "Failed to write core file for process %s (error %d)\n", 1164 curproc->p_comm, error); 1165 } 1166 1167 done: 1168 #ifdef COMPRESS_USER_CORES 1169 if (core_buf) 1170 free(core_buf, M_TEMP); 1171 if (gzfile) 1172 gzclose(gzfile); 1173 #endif 1174 1175 free(hdr, M_TEMP); 1176 1177 return (error); 1178 } 1179 1180 /* 1181 * A callback for each_writable_segment() to write out the segment's 1182 * program header entry. 1183 */ 1184 static void 1185 cb_put_phdr(entry, closure) 1186 vm_map_entry_t entry; 1187 void *closure; 1188 { 1189 struct phdr_closure *phc = (struct phdr_closure *)closure; 1190 Elf_Phdr *phdr = phc->phdr; 1191 1192 phc->offset = round_page(phc->offset); 1193 1194 phdr->p_type = PT_LOAD; 1195 phdr->p_offset = phc->offset; 1196 phdr->p_vaddr = entry->start; 1197 phdr->p_paddr = 0; 1198 phdr->p_filesz = phdr->p_memsz = entry->end - entry->start; 1199 phdr->p_align = PAGE_SIZE; 1200 phdr->p_flags = __elfN(untrans_prot)(entry->protection); 1201 1202 phc->offset += phdr->p_filesz; 1203 phc->phdr++; 1204 } 1205 1206 /* 1207 * A callback for each_writable_segment() to gather information about 1208 * the number of segments and their total size. 1209 */ 1210 static void 1211 cb_size_segment(entry, closure) 1212 vm_map_entry_t entry; 1213 void *closure; 1214 { 1215 struct sseg_closure *ssc = (struct sseg_closure *)closure; 1216 1217 ssc->count++; 1218 ssc->size += entry->end - entry->start; 1219 } 1220 1221 /* 1222 * For each writable segment in the process's memory map, call the given 1223 * function with a pointer to the map entry and some arbitrary 1224 * caller-supplied data. 1225 */ 1226 static void 1227 each_writable_segment(td, func, closure) 1228 struct thread *td; 1229 segment_callback func; 1230 void *closure; 1231 { 1232 struct proc *p = td->td_proc; 1233 vm_map_t map = &p->p_vmspace->vm_map; 1234 vm_map_entry_t entry; 1235 vm_object_t backing_object, object; 1236 boolean_t ignore_entry; 1237 1238 vm_map_lock_read(map); 1239 for (entry = map->header.next; entry != &map->header; 1240 entry = entry->next) { 1241 /* 1242 * Don't dump inaccessible mappings, deal with legacy 1243 * coredump mode. 1244 * 1245 * Note that read-only segments related to the elf binary 1246 * are marked MAP_ENTRY_NOCOREDUMP now so we no longer 1247 * need to arbitrarily ignore such segments. 1248 */ 1249 if (elf_legacy_coredump) { 1250 if ((entry->protection & VM_PROT_RW) != VM_PROT_RW) 1251 continue; 1252 } else { 1253 if ((entry->protection & VM_PROT_ALL) == 0) 1254 continue; 1255 } 1256 1257 /* 1258 * Dont include memory segment in the coredump if 1259 * MAP_NOCORE is set in mmap(2) or MADV_NOCORE in 1260 * madvise(2). Do not dump submaps (i.e. parts of the 1261 * kernel map). 1262 */ 1263 if (entry->eflags & (MAP_ENTRY_NOCOREDUMP|MAP_ENTRY_IS_SUB_MAP)) 1264 continue; 1265 1266 if ((object = entry->object.vm_object) == NULL) 1267 continue; 1268 1269 /* Ignore memory-mapped devices and such things. */ 1270 VM_OBJECT_LOCK(object); 1271 while ((backing_object = object->backing_object) != NULL) { 1272 VM_OBJECT_LOCK(backing_object); 1273 VM_OBJECT_UNLOCK(object); 1274 object = backing_object; 1275 } 1276 ignore_entry = object->type != OBJT_DEFAULT && 1277 object->type != OBJT_SWAP && object->type != OBJT_VNODE; 1278 VM_OBJECT_UNLOCK(object); 1279 if (ignore_entry) 1280 continue; 1281 1282 (*func)(entry, closure); 1283 } 1284 vm_map_unlock_read(map); 1285 } 1286 1287 /* 1288 * Write the core file header to the file, including padding up to 1289 * the page boundary. 1290 */ 1291 static int 1292 __elfN(corehdr)(td, vp, cred, numsegs, hdr, hdrsize, gzfile) 1293 struct thread *td; 1294 struct vnode *vp; 1295 struct ucred *cred; 1296 int numsegs; 1297 size_t hdrsize; 1298 void *hdr; 1299 gzFile gzfile; 1300 { 1301 size_t off; 1302 1303 /* Fill in the header. */ 1304 bzero(hdr, hdrsize); 1305 off = 0; 1306 __elfN(puthdr)(td, hdr, &off, numsegs); 1307 1308 if (!gzfile) { 1309 /* Write it to the core file. */ 1310 return (vn_rdwr_inchunks(UIO_WRITE, vp, hdr, hdrsize, (off_t)0, 1311 UIO_SYSSPACE, IO_UNIT | IO_DIRECT, cred, NOCRED, NULL, 1312 td)); 1313 } else { 1314 #ifdef COMPRESS_USER_CORES 1315 if (gzwrite(gzfile, hdr, hdrsize) != hdrsize) { 1316 log(LOG_WARNING, 1317 "Failed to compress core file header for process" 1318 " %s.\n", curproc->p_comm); 1319 return (EFAULT); 1320 } 1321 else { 1322 return (0); 1323 } 1324 #else 1325 panic("shouldn't be here"); 1326 #endif 1327 } 1328 } 1329 1330 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32 1331 #include <compat/freebsd32/freebsd32.h> 1332 1333 typedef struct prstatus32 elf_prstatus_t; 1334 typedef struct prpsinfo32 elf_prpsinfo_t; 1335 typedef struct fpreg32 elf_prfpregset_t; 1336 typedef struct fpreg32 elf_fpregset_t; 1337 typedef struct reg32 elf_gregset_t; 1338 typedef struct thrmisc32 elf_thrmisc_t; 1339 #else 1340 typedef prstatus_t elf_prstatus_t; 1341 typedef prpsinfo_t elf_prpsinfo_t; 1342 typedef prfpregset_t elf_prfpregset_t; 1343 typedef prfpregset_t elf_fpregset_t; 1344 typedef gregset_t elf_gregset_t; 1345 typedef thrmisc_t elf_thrmisc_t; 1346 #endif 1347 1348 static void 1349 __elfN(puthdr)(struct thread *td, void *dst, size_t *off, int numsegs) 1350 { 1351 struct { 1352 elf_prstatus_t status; 1353 elf_prfpregset_t fpregset; 1354 elf_prpsinfo_t psinfo; 1355 elf_thrmisc_t thrmisc; 1356 } *tempdata; 1357 elf_prstatus_t *status; 1358 elf_prfpregset_t *fpregset; 1359 elf_prpsinfo_t *psinfo; 1360 elf_thrmisc_t *thrmisc; 1361 struct proc *p; 1362 struct thread *thr; 1363 size_t ehoff, noteoff, notesz, phoff; 1364 1365 p = td->td_proc; 1366 1367 ehoff = *off; 1368 *off += sizeof(Elf_Ehdr); 1369 1370 phoff = *off; 1371 *off += (numsegs + 1) * sizeof(Elf_Phdr); 1372 1373 noteoff = *off; 1374 /* 1375 * Don't allocate space for the notes if we're just calculating 1376 * the size of the header. We also don't collect the data. 1377 */ 1378 if (dst != NULL) { 1379 tempdata = malloc(sizeof(*tempdata), M_TEMP, M_ZERO|M_WAITOK); 1380 status = &tempdata->status; 1381 fpregset = &tempdata->fpregset; 1382 psinfo = &tempdata->psinfo; 1383 thrmisc = &tempdata->thrmisc; 1384 } else { 1385 tempdata = NULL; 1386 status = NULL; 1387 fpregset = NULL; 1388 psinfo = NULL; 1389 thrmisc = NULL; 1390 } 1391 1392 if (dst != NULL) { 1393 psinfo->pr_version = PRPSINFO_VERSION; 1394 psinfo->pr_psinfosz = sizeof(elf_prpsinfo_t); 1395 strlcpy(psinfo->pr_fname, p->p_comm, sizeof(psinfo->pr_fname)); 1396 /* 1397 * XXX - We don't fill in the command line arguments properly 1398 * yet. 1399 */ 1400 strlcpy(psinfo->pr_psargs, p->p_comm, 1401 sizeof(psinfo->pr_psargs)); 1402 } 1403 __elfN(putnote)(dst, off, "FreeBSD", NT_PRPSINFO, psinfo, 1404 sizeof *psinfo); 1405 1406 /* 1407 * To have the debugger select the right thread (LWP) as the initial 1408 * thread, we dump the state of the thread passed to us in td first. 1409 * This is the thread that causes the core dump and thus likely to 1410 * be the right thread one wants to have selected in the debugger. 1411 */ 1412 thr = td; 1413 while (thr != NULL) { 1414 if (dst != NULL) { 1415 status->pr_version = PRSTATUS_VERSION; 1416 status->pr_statussz = sizeof(elf_prstatus_t); 1417 status->pr_gregsetsz = sizeof(elf_gregset_t); 1418 status->pr_fpregsetsz = sizeof(elf_fpregset_t); 1419 status->pr_osreldate = osreldate; 1420 status->pr_cursig = p->p_sig; 1421 status->pr_pid = thr->td_tid; 1422 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32 1423 fill_regs32(thr, &status->pr_reg); 1424 fill_fpregs32(thr, fpregset); 1425 #else 1426 fill_regs(thr, &status->pr_reg); 1427 fill_fpregs(thr, fpregset); 1428 #endif 1429 memset(&thrmisc->_pad, 0, sizeof (thrmisc->_pad)); 1430 strcpy(thrmisc->pr_tname, thr->td_name); 1431 } 1432 __elfN(putnote)(dst, off, "FreeBSD", NT_PRSTATUS, status, 1433 sizeof *status); 1434 __elfN(putnote)(dst, off, "FreeBSD", NT_FPREGSET, fpregset, 1435 sizeof *fpregset); 1436 __elfN(putnote)(dst, off, "FreeBSD", NT_THRMISC, thrmisc, 1437 sizeof *thrmisc); 1438 /* 1439 * Allow for MD specific notes, as well as any MD 1440 * specific preparations for writing MI notes. 1441 */ 1442 __elfN(dump_thread)(thr, dst, off); 1443 1444 thr = (thr == td) ? TAILQ_FIRST(&p->p_threads) : 1445 TAILQ_NEXT(thr, td_plist); 1446 if (thr == td) 1447 thr = TAILQ_NEXT(thr, td_plist); 1448 } 1449 1450 notesz = *off - noteoff; 1451 1452 if (dst != NULL) 1453 free(tempdata, M_TEMP); 1454 1455 /* Align up to a page boundary for the program segments. */ 1456 *off = round_page(*off); 1457 1458 if (dst != NULL) { 1459 Elf_Ehdr *ehdr; 1460 Elf_Phdr *phdr; 1461 struct phdr_closure phc; 1462 1463 /* 1464 * Fill in the ELF header. 1465 */ 1466 ehdr = (Elf_Ehdr *)((char *)dst + ehoff); 1467 ehdr->e_ident[EI_MAG0] = ELFMAG0; 1468 ehdr->e_ident[EI_MAG1] = ELFMAG1; 1469 ehdr->e_ident[EI_MAG2] = ELFMAG2; 1470 ehdr->e_ident[EI_MAG3] = ELFMAG3; 1471 ehdr->e_ident[EI_CLASS] = ELF_CLASS; 1472 ehdr->e_ident[EI_DATA] = ELF_DATA; 1473 ehdr->e_ident[EI_VERSION] = EV_CURRENT; 1474 ehdr->e_ident[EI_OSABI] = ELFOSABI_FREEBSD; 1475 ehdr->e_ident[EI_ABIVERSION] = 0; 1476 ehdr->e_ident[EI_PAD] = 0; 1477 ehdr->e_type = ET_CORE; 1478 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32 1479 ehdr->e_machine = ELF_ARCH32; 1480 #else 1481 ehdr->e_machine = ELF_ARCH; 1482 #endif 1483 ehdr->e_version = EV_CURRENT; 1484 ehdr->e_entry = 0; 1485 ehdr->e_phoff = phoff; 1486 ehdr->e_flags = 0; 1487 ehdr->e_ehsize = sizeof(Elf_Ehdr); 1488 ehdr->e_phentsize = sizeof(Elf_Phdr); 1489 ehdr->e_phnum = numsegs + 1; 1490 ehdr->e_shentsize = sizeof(Elf_Shdr); 1491 ehdr->e_shnum = 0; 1492 ehdr->e_shstrndx = SHN_UNDEF; 1493 1494 /* 1495 * Fill in the program header entries. 1496 */ 1497 phdr = (Elf_Phdr *)((char *)dst + phoff); 1498 1499 /* The note segement. */ 1500 phdr->p_type = PT_NOTE; 1501 phdr->p_offset = noteoff; 1502 phdr->p_vaddr = 0; 1503 phdr->p_paddr = 0; 1504 phdr->p_filesz = notesz; 1505 phdr->p_memsz = 0; 1506 phdr->p_flags = 0; 1507 phdr->p_align = 0; 1508 phdr++; 1509 1510 /* All the writable segments from the program. */ 1511 phc.phdr = phdr; 1512 phc.offset = *off; 1513 each_writable_segment(td, cb_put_phdr, &phc); 1514 } 1515 } 1516 1517 static void 1518 __elfN(putnote)(void *dst, size_t *off, const char *name, int type, 1519 const void *desc, size_t descsz) 1520 { 1521 Elf_Note note; 1522 1523 note.n_namesz = strlen(name) + 1; 1524 note.n_descsz = descsz; 1525 note.n_type = type; 1526 if (dst != NULL) 1527 bcopy(¬e, (char *)dst + *off, sizeof note); 1528 *off += sizeof note; 1529 if (dst != NULL) 1530 bcopy(name, (char *)dst + *off, note.n_namesz); 1531 *off += roundup2(note.n_namesz, sizeof(Elf_Size)); 1532 if (dst != NULL) 1533 bcopy(desc, (char *)dst + *off, note.n_descsz); 1534 *off += roundup2(note.n_descsz, sizeof(Elf_Size)); 1535 } 1536 1537 /* 1538 * Try to find the appropriate ABI-note section for checknote, 1539 * fetch the osreldate for binary from the ELF OSABI-note. Only the 1540 * first page of the image is searched, the same as for headers. 1541 */ 1542 static boolean_t 1543 __elfN(check_note)(struct image_params *imgp, Elf_Brandnote *checknote, 1544 int32_t *osrel) 1545 { 1546 const Elf_Note *note, *note0, *note_end; 1547 const Elf_Phdr *phdr, *pnote; 1548 const Elf_Ehdr *hdr; 1549 const char *note_name; 1550 int i; 1551 1552 pnote = NULL; 1553 hdr = (const Elf_Ehdr *)imgp->image_header; 1554 phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff); 1555 1556 for (i = 0; i < hdr->e_phnum; i++) { 1557 if (phdr[i].p_type == PT_NOTE) { 1558 pnote = &phdr[i]; 1559 break; 1560 } 1561 } 1562 1563 if (pnote == NULL || pnote->p_offset >= PAGE_SIZE || 1564 pnote->p_offset + pnote->p_filesz >= PAGE_SIZE) 1565 return (FALSE); 1566 1567 note = note0 = (const Elf_Note *)(imgp->image_header + pnote->p_offset); 1568 note_end = (const Elf_Note *)(imgp->image_header + 1569 pnote->p_offset + pnote->p_filesz); 1570 for (i = 0; i < 100 && note >= note0 && note < note_end; i++) { 1571 if (!aligned(note, Elf32_Addr)) 1572 return (FALSE); 1573 if (note->n_namesz != checknote->hdr.n_namesz || 1574 note->n_descsz != checknote->hdr.n_descsz || 1575 note->n_type != checknote->hdr.n_type) 1576 goto nextnote; 1577 note_name = (const char *)(note + 1); 1578 if (strncmp(checknote->vendor, note_name, 1579 checknote->hdr.n_namesz) != 0) 1580 goto nextnote; 1581 1582 /* 1583 * Fetch the osreldate for binary 1584 * from the ELF OSABI-note if necessary. 1585 */ 1586 if ((checknote->flags & BN_TRANSLATE_OSREL) != 0 && 1587 checknote->trans_osrel != NULL) 1588 return (checknote->trans_osrel(note, osrel)); 1589 return (TRUE); 1590 1591 nextnote: 1592 note = (const Elf_Note *)((const char *)(note + 1) + 1593 roundup2(note->n_namesz, sizeof(Elf32_Addr)) + 1594 roundup2(note->n_descsz, sizeof(Elf32_Addr))); 1595 } 1596 1597 return (FALSE); 1598 } 1599 1600 /* 1601 * Tell kern_execve.c about it, with a little help from the linker. 1602 */ 1603 static struct execsw __elfN(execsw) = { 1604 __CONCAT(exec_, __elfN(imgact)), 1605 __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) 1606 }; 1607 EXEC_SET(__CONCAT(elf, __ELF_WORD_SIZE), __elfN(execsw)); 1608 1609 #ifdef COMPRESS_USER_CORES 1610 /* 1611 * Compress and write out a core segment for a user process. 1612 * 1613 * 'inbuf' is the starting address of a VM segment in the process' address 1614 * space that is to be compressed and written out to the core file. 'dest_buf' 1615 * is a buffer in the kernel's address space. The segment is copied from 1616 * 'inbuf' to 'dest_buf' first before being processed by the compression 1617 * routine gzwrite(). This copying is necessary because the content of the VM 1618 * segment may change between the compression pass and the crc-computation pass 1619 * in gzwrite(). This is because realtime threads may preempt the UNIX kernel. 1620 */ 1621 static int 1622 compress_core (gzFile file, char *inbuf, char *dest_buf, unsigned int len, 1623 struct thread *td) 1624 { 1625 int len_compressed; 1626 int error = 0; 1627 unsigned int chunk_len; 1628 1629 while (len) { 1630 chunk_len = (len > CORE_BUF_SIZE) ? CORE_BUF_SIZE : len; 1631 copyin(inbuf, dest_buf, chunk_len); 1632 len_compressed = gzwrite(file, dest_buf, chunk_len); 1633 1634 EVENTHANDLER_INVOKE(app_coredump_progress, td, len_compressed); 1635 1636 if ((unsigned int)len_compressed != chunk_len) { 1637 log(LOG_WARNING, 1638 "compress_core: length mismatch (0x%x returned, " 1639 "0x%x expected)\n", len_compressed, chunk_len); 1640 EVENTHANDLER_INVOKE(app_coredump_error, td, 1641 "compress_core: length mismatch %x -> %x", 1642 chunk_len, len_compressed); 1643 error = EFAULT; 1644 break; 1645 } 1646 inbuf += chunk_len; 1647 len -= chunk_len; 1648 maybe_yield(); 1649 } 1650 1651 return (error); 1652 } 1653 #endif /* COMPRESS_USER_CORES */ 1654 1655 static vm_prot_t 1656 __elfN(trans_prot)(Elf_Word flags) 1657 { 1658 vm_prot_t prot; 1659 1660 prot = 0; 1661 if (flags & PF_X) 1662 prot |= VM_PROT_EXECUTE; 1663 if (flags & PF_W) 1664 prot |= VM_PROT_WRITE; 1665 if (flags & PF_R) 1666 prot |= VM_PROT_READ; 1667 return (prot); 1668 } 1669 1670 static Elf_Word 1671 __elfN(untrans_prot)(vm_prot_t prot) 1672 { 1673 Elf_Word flags; 1674 1675 flags = 0; 1676 if (prot & VM_PROT_EXECUTE) 1677 flags |= PF_X; 1678 if (prot & VM_PROT_READ) 1679 flags |= PF_R; 1680 if (prot & VM_PROT_WRITE) 1681 flags |= PF_W; 1682 return (flags); 1683 } 1684