1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 2017 Dell EMC 5 * Copyright (c) 2000-2001, 2003 David O'Brien 6 * Copyright (c) 1995-1996 Søren Schmidt 7 * Copyright (c) 1996 Peter Wemm 8 * All rights reserved. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer 15 * in this position and unchanged. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. The name of the author may not be used to endorse or promote products 20 * derived from this software without specific prior written permission 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 25 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 27 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 28 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 31 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34 #include <sys/cdefs.h> 35 __FBSDID("$FreeBSD$"); 36 37 #include "opt_capsicum.h" 38 39 #include <sys/param.h> 40 #include <sys/capsicum.h> 41 #include <sys/compressor.h> 42 #include <sys/exec.h> 43 #include <sys/fcntl.h> 44 #include <sys/imgact.h> 45 #include <sys/imgact_elf.h> 46 #include <sys/jail.h> 47 #include <sys/kernel.h> 48 #include <sys/lock.h> 49 #include <sys/malloc.h> 50 #include <sys/mount.h> 51 #include <sys/mman.h> 52 #include <sys/namei.h> 53 #include <sys/proc.h> 54 #include <sys/procfs.h> 55 #include <sys/ptrace.h> 56 #include <sys/racct.h> 57 #include <sys/reg.h> 58 #include <sys/resourcevar.h> 59 #include <sys/rwlock.h> 60 #include <sys/sbuf.h> 61 #include <sys/sf_buf.h> 62 #include <sys/smp.h> 63 #include <sys/systm.h> 64 #include <sys/signalvar.h> 65 #include <sys/stat.h> 66 #include <sys/sx.h> 67 #include <sys/syscall.h> 68 #include <sys/sysctl.h> 69 #include <sys/sysent.h> 70 #include <sys/vnode.h> 71 #include <sys/syslog.h> 72 #include <sys/eventhandler.h> 73 #include <sys/user.h> 74 75 #include <vm/vm.h> 76 #include <vm/vm_kern.h> 77 #include <vm/vm_param.h> 78 #include <vm/pmap.h> 79 #include <vm/vm_map.h> 80 #include <vm/vm_object.h> 81 #include <vm/vm_extern.h> 82 83 #include <machine/elf.h> 84 #include <machine/md_var.h> 85 86 #define ELF_NOTE_ROUNDSIZE 4 87 #define OLD_EI_BRAND 8 88 89 static int __elfN(check_header)(const Elf_Ehdr *hdr); 90 static Elf_Brandinfo *__elfN(get_brandinfo)(struct image_params *imgp, 91 const char *interp, int32_t *osrel, uint32_t *fctl0); 92 static int __elfN(load_file)(struct proc *p, const char *file, u_long *addr, 93 u_long *entry); 94 static int __elfN(load_section)(struct image_params *imgp, vm_ooffset_t offset, 95 caddr_t vmaddr, size_t memsz, size_t filsz, vm_prot_t prot); 96 static int __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp); 97 static bool __elfN(freebsd_trans_osrel)(const Elf_Note *note, 98 int32_t *osrel); 99 static bool kfreebsd_trans_osrel(const Elf_Note *note, int32_t *osrel); 100 static boolean_t __elfN(check_note)(struct image_params *imgp, 101 Elf_Brandnote *checknote, int32_t *osrel, boolean_t *has_fctl0, 102 uint32_t *fctl0); 103 static vm_prot_t __elfN(trans_prot)(Elf_Word); 104 static Elf_Word __elfN(untrans_prot)(vm_prot_t); 105 106 SYSCTL_NODE(_kern, OID_AUTO, __CONCAT(elf, __ELF_WORD_SIZE), 107 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 108 ""); 109 110 int __elfN(fallback_brand) = -1; 111 SYSCTL_INT(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO, 112 fallback_brand, CTLFLAG_RWTUN, &__elfN(fallback_brand), 0, 113 __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) " brand of last resort"); 114 115 static int elf_legacy_coredump = 0; 116 SYSCTL_INT(_debug, OID_AUTO, __elfN(legacy_coredump), CTLFLAG_RW, 117 &elf_legacy_coredump, 0, 118 "include all and only RW pages in core dumps"); 119 120 int __elfN(nxstack) = 121 #if defined(__amd64__) || defined(__powerpc64__) /* both 64 and 32 bit */ || \ 122 (defined(__arm__) && __ARM_ARCH >= 7) || defined(__aarch64__) || \ 123 defined(__riscv) 124 1; 125 #else 126 0; 127 #endif 128 SYSCTL_INT(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO, 129 nxstack, CTLFLAG_RW, &__elfN(nxstack), 0, 130 __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) ": enable non-executable stack"); 131 132 #if __ELF_WORD_SIZE == 32 && (defined(__amd64__) || defined(__i386__)) 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 137 138 static u_long __elfN(pie_base) = ET_DYN_LOAD_ADDR; 139 static int 140 sysctl_pie_base(SYSCTL_HANDLER_ARGS) 141 { 142 u_long val; 143 int error; 144 145 val = __elfN(pie_base); 146 error = sysctl_handle_long(oidp, &val, 0, req); 147 if (error != 0 || req->newptr == NULL) 148 return (error); 149 if ((val & PAGE_MASK) != 0) 150 return (EINVAL); 151 __elfN(pie_base) = val; 152 return (0); 153 } 154 SYSCTL_PROC(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO, pie_base, 155 CTLTYPE_ULONG | CTLFLAG_MPSAFE | CTLFLAG_RW, NULL, 0, 156 sysctl_pie_base, "LU", 157 "PIE load base without randomization"); 158 159 SYSCTL_NODE(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO, aslr, 160 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 161 ""); 162 #define ASLR_NODE_OID __CONCAT(__CONCAT(_kern_elf, __ELF_WORD_SIZE), _aslr) 163 164 static int __elfN(aslr_enabled) = 0; 165 SYSCTL_INT(ASLR_NODE_OID, OID_AUTO, enable, CTLFLAG_RWTUN, 166 &__elfN(aslr_enabled), 0, 167 __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) 168 ": enable address map randomization"); 169 170 static int __elfN(pie_aslr_enabled) = 0; 171 SYSCTL_INT(ASLR_NODE_OID, OID_AUTO, pie_enable, CTLFLAG_RWTUN, 172 &__elfN(pie_aslr_enabled), 0, 173 __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) 174 ": enable address map randomization for PIE binaries"); 175 176 static int __elfN(aslr_honor_sbrk) = 1; 177 SYSCTL_INT(ASLR_NODE_OID, OID_AUTO, honor_sbrk, CTLFLAG_RW, 178 &__elfN(aslr_honor_sbrk), 0, 179 __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) ": assume sbrk is used"); 180 181 static int __elfN(aslr_stack_gap) = 3; 182 SYSCTL_INT(ASLR_NODE_OID, OID_AUTO, stack_gap, CTLFLAG_RW, 183 &__elfN(aslr_stack_gap), 0, 184 __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) 185 ": maximum percentage of main stack to waste on a random gap"); 186 187 static int __elfN(sigfastblock) = 1; 188 SYSCTL_INT(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO, sigfastblock, 189 CTLFLAG_RWTUN, &__elfN(sigfastblock), 0, 190 "enable sigfastblock for new processes"); 191 192 static bool __elfN(allow_wx) = true; 193 SYSCTL_BOOL(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO, allow_wx, 194 CTLFLAG_RWTUN, &__elfN(allow_wx), 0, 195 "Allow pages to be mapped simultaneously writable and executable"); 196 197 static Elf_Brandinfo *elf_brand_list[MAX_BRANDS]; 198 199 #define aligned(a, t) (rounddown2((u_long)(a), sizeof(t)) == (u_long)(a)) 200 201 Elf_Brandnote __elfN(freebsd_brandnote) = { 202 .hdr.n_namesz = sizeof(FREEBSD_ABI_VENDOR), 203 .hdr.n_descsz = sizeof(int32_t), 204 .hdr.n_type = NT_FREEBSD_ABI_TAG, 205 .vendor = FREEBSD_ABI_VENDOR, 206 .flags = BN_TRANSLATE_OSREL, 207 .trans_osrel = __elfN(freebsd_trans_osrel) 208 }; 209 210 static bool 211 __elfN(freebsd_trans_osrel)(const Elf_Note *note, int32_t *osrel) 212 { 213 uintptr_t p; 214 215 p = (uintptr_t)(note + 1); 216 p += roundup2(note->n_namesz, ELF_NOTE_ROUNDSIZE); 217 *osrel = *(const int32_t *)(p); 218 219 return (true); 220 } 221 222 static const char GNU_ABI_VENDOR[] = "GNU"; 223 static int GNU_KFREEBSD_ABI_DESC = 3; 224 225 Elf_Brandnote __elfN(kfreebsd_brandnote) = { 226 .hdr.n_namesz = sizeof(GNU_ABI_VENDOR), 227 .hdr.n_descsz = 16, /* XXX at least 16 */ 228 .hdr.n_type = 1, 229 .vendor = GNU_ABI_VENDOR, 230 .flags = BN_TRANSLATE_OSREL, 231 .trans_osrel = kfreebsd_trans_osrel 232 }; 233 234 static bool 235 kfreebsd_trans_osrel(const Elf_Note *note, int32_t *osrel) 236 { 237 const Elf32_Word *desc; 238 uintptr_t p; 239 240 p = (uintptr_t)(note + 1); 241 p += roundup2(note->n_namesz, ELF_NOTE_ROUNDSIZE); 242 243 desc = (const Elf32_Word *)p; 244 if (desc[0] != GNU_KFREEBSD_ABI_DESC) 245 return (false); 246 247 /* 248 * Debian GNU/kFreeBSD embed the earliest compatible kernel version 249 * (__FreeBSD_version: <major><two digit minor>Rxx) in the LSB way. 250 */ 251 *osrel = desc[1] * 100000 + desc[2] * 1000 + desc[3]; 252 253 return (true); 254 } 255 256 int 257 __elfN(insert_brand_entry)(Elf_Brandinfo *entry) 258 { 259 int i; 260 261 for (i = 0; i < MAX_BRANDS; i++) { 262 if (elf_brand_list[i] == NULL) { 263 elf_brand_list[i] = entry; 264 break; 265 } 266 } 267 if (i == MAX_BRANDS) { 268 printf("WARNING: %s: could not insert brandinfo entry: %p\n", 269 __func__, entry); 270 return (-1); 271 } 272 return (0); 273 } 274 275 int 276 __elfN(remove_brand_entry)(Elf_Brandinfo *entry) 277 { 278 int i; 279 280 for (i = 0; i < MAX_BRANDS; i++) { 281 if (elf_brand_list[i] == entry) { 282 elf_brand_list[i] = NULL; 283 break; 284 } 285 } 286 if (i == MAX_BRANDS) 287 return (-1); 288 return (0); 289 } 290 291 int 292 __elfN(brand_inuse)(Elf_Brandinfo *entry) 293 { 294 struct proc *p; 295 int rval = FALSE; 296 297 sx_slock(&allproc_lock); 298 FOREACH_PROC_IN_SYSTEM(p) { 299 if (p->p_sysent == entry->sysvec) { 300 rval = TRUE; 301 break; 302 } 303 } 304 sx_sunlock(&allproc_lock); 305 306 return (rval); 307 } 308 309 static Elf_Brandinfo * 310 __elfN(get_brandinfo)(struct image_params *imgp, const char *interp, 311 int32_t *osrel, uint32_t *fctl0) 312 { 313 const Elf_Ehdr *hdr = (const Elf_Ehdr *)imgp->image_header; 314 Elf_Brandinfo *bi, *bi_m; 315 boolean_t ret, has_fctl0; 316 int i, interp_name_len; 317 318 interp_name_len = interp != NULL ? strlen(interp) + 1 : 0; 319 320 /* 321 * We support four types of branding -- (1) the ELF EI_OSABI field 322 * that SCO added to the ELF spec, (2) FreeBSD 3.x's traditional string 323 * branding w/in the ELF header, (3) path of the `interp_path' 324 * field, and (4) the ".note.ABI-tag" ELF section. 325 */ 326 327 /* Look for an ".note.ABI-tag" ELF section */ 328 bi_m = NULL; 329 for (i = 0; i < MAX_BRANDS; i++) { 330 bi = elf_brand_list[i]; 331 if (bi == NULL) 332 continue; 333 if (interp != NULL && (bi->flags & BI_BRAND_ONLY_STATIC) != 0) 334 continue; 335 if (hdr->e_machine == bi->machine && (bi->flags & 336 (BI_BRAND_NOTE|BI_BRAND_NOTE_MANDATORY)) != 0) { 337 has_fctl0 = false; 338 *fctl0 = 0; 339 *osrel = 0; 340 ret = __elfN(check_note)(imgp, bi->brand_note, osrel, 341 &has_fctl0, fctl0); 342 /* Give brand a chance to veto check_note's guess */ 343 if (ret && bi->header_supported) { 344 ret = bi->header_supported(imgp, osrel, 345 has_fctl0 ? fctl0 : NULL); 346 } 347 /* 348 * If note checker claimed the binary, but the 349 * interpreter path in the image does not 350 * match default one for the brand, try to 351 * search for other brands with the same 352 * interpreter. Either there is better brand 353 * with the right interpreter, or, failing 354 * this, we return first brand which accepted 355 * our note and, optionally, header. 356 */ 357 if (ret && bi_m == NULL && interp != NULL && 358 (bi->interp_path == NULL || 359 (strlen(bi->interp_path) + 1 != interp_name_len || 360 strncmp(interp, bi->interp_path, interp_name_len) 361 != 0))) { 362 bi_m = bi; 363 ret = 0; 364 } 365 if (ret) 366 return (bi); 367 } 368 } 369 if (bi_m != NULL) 370 return (bi_m); 371 372 /* If the executable has a brand, search for it in the brand list. */ 373 for (i = 0; i < MAX_BRANDS; i++) { 374 bi = elf_brand_list[i]; 375 if (bi == NULL || (bi->flags & BI_BRAND_NOTE_MANDATORY) != 0 || 376 (interp != NULL && (bi->flags & BI_BRAND_ONLY_STATIC) != 0)) 377 continue; 378 if (hdr->e_machine == bi->machine && 379 (hdr->e_ident[EI_OSABI] == bi->brand || 380 (bi->compat_3_brand != NULL && 381 strcmp((const char *)&hdr->e_ident[OLD_EI_BRAND], 382 bi->compat_3_brand) == 0))) { 383 /* Looks good, but give brand a chance to veto */ 384 if (bi->header_supported == NULL || 385 bi->header_supported(imgp, NULL, NULL)) { 386 /* 387 * Again, prefer strictly matching 388 * interpreter path. 389 */ 390 if (interp_name_len == 0 && 391 bi->interp_path == NULL) 392 return (bi); 393 if (bi->interp_path != NULL && 394 strlen(bi->interp_path) + 1 == 395 interp_name_len && strncmp(interp, 396 bi->interp_path, interp_name_len) == 0) 397 return (bi); 398 if (bi_m == NULL) 399 bi_m = bi; 400 } 401 } 402 } 403 if (bi_m != NULL) 404 return (bi_m); 405 406 /* No known brand, see if the header is recognized by any brand */ 407 for (i = 0; i < MAX_BRANDS; i++) { 408 bi = elf_brand_list[i]; 409 if (bi == NULL || bi->flags & BI_BRAND_NOTE_MANDATORY || 410 bi->header_supported == NULL) 411 continue; 412 if (hdr->e_machine == bi->machine) { 413 ret = bi->header_supported(imgp, NULL, NULL); 414 if (ret) 415 return (bi); 416 } 417 } 418 419 /* Lacking a known brand, search for a recognized interpreter. */ 420 if (interp != NULL) { 421 for (i = 0; i < MAX_BRANDS; i++) { 422 bi = elf_brand_list[i]; 423 if (bi == NULL || (bi->flags & 424 (BI_BRAND_NOTE_MANDATORY | BI_BRAND_ONLY_STATIC)) 425 != 0) 426 continue; 427 if (hdr->e_machine == bi->machine && 428 bi->interp_path != NULL && 429 /* ELF image p_filesz includes terminating zero */ 430 strlen(bi->interp_path) + 1 == interp_name_len && 431 strncmp(interp, bi->interp_path, interp_name_len) 432 == 0 && (bi->header_supported == NULL || 433 bi->header_supported(imgp, NULL, NULL))) 434 return (bi); 435 } 436 } 437 438 /* Lacking a recognized interpreter, try the default brand */ 439 for (i = 0; i < MAX_BRANDS; i++) { 440 bi = elf_brand_list[i]; 441 if (bi == NULL || (bi->flags & BI_BRAND_NOTE_MANDATORY) != 0 || 442 (interp != NULL && (bi->flags & BI_BRAND_ONLY_STATIC) != 0)) 443 continue; 444 if (hdr->e_machine == bi->machine && 445 __elfN(fallback_brand) == bi->brand && 446 (bi->header_supported == NULL || 447 bi->header_supported(imgp, NULL, NULL))) 448 return (bi); 449 } 450 return (NULL); 451 } 452 453 static bool 454 __elfN(phdr_in_zero_page)(const Elf_Ehdr *hdr) 455 { 456 return (hdr->e_phoff <= PAGE_SIZE && 457 (u_int)hdr->e_phentsize * hdr->e_phnum <= PAGE_SIZE - hdr->e_phoff); 458 } 459 460 static int 461 __elfN(check_header)(const Elf_Ehdr *hdr) 462 { 463 Elf_Brandinfo *bi; 464 int i; 465 466 if (!IS_ELF(*hdr) || 467 hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS || 468 hdr->e_ident[EI_DATA] != ELF_TARG_DATA || 469 hdr->e_ident[EI_VERSION] != EV_CURRENT || 470 hdr->e_phentsize != sizeof(Elf_Phdr) || 471 hdr->e_version != ELF_TARG_VER) 472 return (ENOEXEC); 473 474 /* 475 * Make sure we have at least one brand for this machine. 476 */ 477 478 for (i = 0; i < MAX_BRANDS; i++) { 479 bi = elf_brand_list[i]; 480 if (bi != NULL && bi->machine == hdr->e_machine) 481 break; 482 } 483 if (i == MAX_BRANDS) 484 return (ENOEXEC); 485 486 return (0); 487 } 488 489 static int 490 __elfN(map_partial)(vm_map_t map, vm_object_t object, vm_ooffset_t offset, 491 vm_offset_t start, vm_offset_t end, vm_prot_t prot) 492 { 493 struct sf_buf *sf; 494 int error; 495 vm_offset_t off; 496 497 /* 498 * Create the page if it doesn't exist yet. Ignore errors. 499 */ 500 vm_map_fixed(map, NULL, 0, trunc_page(start), round_page(end) - 501 trunc_page(start), VM_PROT_ALL, VM_PROT_ALL, MAP_CHECK_EXCL); 502 503 /* 504 * Find the page from the underlying object. 505 */ 506 if (object != NULL) { 507 sf = vm_imgact_map_page(object, offset); 508 if (sf == NULL) 509 return (KERN_FAILURE); 510 off = offset - trunc_page(offset); 511 error = copyout((caddr_t)sf_buf_kva(sf) + off, (caddr_t)start, 512 end - start); 513 vm_imgact_unmap_page(sf); 514 if (error != 0) 515 return (KERN_FAILURE); 516 } 517 518 return (KERN_SUCCESS); 519 } 520 521 static int 522 __elfN(map_insert)(struct image_params *imgp, vm_map_t map, vm_object_t object, 523 vm_ooffset_t offset, vm_offset_t start, vm_offset_t end, vm_prot_t prot, 524 int cow) 525 { 526 struct sf_buf *sf; 527 vm_offset_t off; 528 vm_size_t sz; 529 int error, locked, rv; 530 531 if (start != trunc_page(start)) { 532 rv = __elfN(map_partial)(map, object, offset, start, 533 round_page(start), prot); 534 if (rv != KERN_SUCCESS) 535 return (rv); 536 offset += round_page(start) - start; 537 start = round_page(start); 538 } 539 if (end != round_page(end)) { 540 rv = __elfN(map_partial)(map, object, offset + 541 trunc_page(end) - start, trunc_page(end), end, prot); 542 if (rv != KERN_SUCCESS) 543 return (rv); 544 end = trunc_page(end); 545 } 546 if (start >= end) 547 return (KERN_SUCCESS); 548 if ((offset & PAGE_MASK) != 0) { 549 /* 550 * The mapping is not page aligned. This means that we have 551 * to copy the data. 552 */ 553 rv = vm_map_fixed(map, NULL, 0, start, end - start, 554 prot | VM_PROT_WRITE, VM_PROT_ALL, MAP_CHECK_EXCL); 555 if (rv != KERN_SUCCESS) 556 return (rv); 557 if (object == NULL) 558 return (KERN_SUCCESS); 559 for (; start < end; start += sz) { 560 sf = vm_imgact_map_page(object, offset); 561 if (sf == NULL) 562 return (KERN_FAILURE); 563 off = offset - trunc_page(offset); 564 sz = end - start; 565 if (sz > PAGE_SIZE - off) 566 sz = PAGE_SIZE - off; 567 error = copyout((caddr_t)sf_buf_kva(sf) + off, 568 (caddr_t)start, sz); 569 vm_imgact_unmap_page(sf); 570 if (error != 0) 571 return (KERN_FAILURE); 572 offset += sz; 573 } 574 } else { 575 vm_object_reference(object); 576 rv = vm_map_fixed(map, object, offset, start, end - start, 577 prot, VM_PROT_ALL, cow | MAP_CHECK_EXCL | 578 (object != NULL ? MAP_VN_EXEC : 0)); 579 if (rv != KERN_SUCCESS) { 580 locked = VOP_ISLOCKED(imgp->vp); 581 VOP_UNLOCK(imgp->vp); 582 vm_object_deallocate(object); 583 vn_lock(imgp->vp, locked | LK_RETRY); 584 return (rv); 585 } else if (object != NULL) { 586 MPASS(imgp->vp->v_object == object); 587 VOP_SET_TEXT_CHECKED(imgp->vp); 588 } 589 } 590 return (KERN_SUCCESS); 591 } 592 593 static int 594 __elfN(load_section)(struct image_params *imgp, vm_ooffset_t offset, 595 caddr_t vmaddr, size_t memsz, size_t filsz, vm_prot_t prot) 596 { 597 struct sf_buf *sf; 598 size_t map_len; 599 vm_map_t map; 600 vm_object_t object; 601 vm_offset_t map_addr; 602 int error, rv, cow; 603 size_t copy_len; 604 vm_ooffset_t file_addr; 605 606 /* 607 * It's necessary to fail if the filsz + offset taken from the 608 * header is greater than the actual file pager object's size. 609 * If we were to allow this, then the vm_map_find() below would 610 * walk right off the end of the file object and into the ether. 611 * 612 * While I'm here, might as well check for something else that 613 * is invalid: filsz cannot be greater than memsz. 614 */ 615 if ((filsz != 0 && (off_t)filsz + offset > imgp->attr->va_size) || 616 filsz > memsz) { 617 uprintf("elf_load_section: truncated ELF file\n"); 618 return (ENOEXEC); 619 } 620 621 object = imgp->object; 622 map = &imgp->proc->p_vmspace->vm_map; 623 map_addr = trunc_page((vm_offset_t)vmaddr); 624 file_addr = trunc_page(offset); 625 626 /* 627 * We have two choices. We can either clear the data in the last page 628 * of an oversized mapping, or we can start the anon mapping a page 629 * early and copy the initialized data into that first page. We 630 * choose the second. 631 */ 632 if (filsz == 0) 633 map_len = 0; 634 else if (memsz > filsz) 635 map_len = trunc_page(offset + filsz) - file_addr; 636 else 637 map_len = round_page(offset + filsz) - file_addr; 638 639 if (map_len != 0) { 640 /* cow flags: don't dump readonly sections in core */ 641 cow = MAP_COPY_ON_WRITE | MAP_PREFAULT | 642 (prot & VM_PROT_WRITE ? 0 : MAP_DISABLE_COREDUMP); 643 644 rv = __elfN(map_insert)(imgp, map, object, file_addr, 645 map_addr, map_addr + map_len, prot, cow); 646 if (rv != KERN_SUCCESS) 647 return (EINVAL); 648 649 /* we can stop now if we've covered it all */ 650 if (memsz == filsz) 651 return (0); 652 } 653 654 /* 655 * We have to get the remaining bit of the file into the first part 656 * of the oversized map segment. This is normally because the .data 657 * segment in the file is extended to provide bss. It's a neat idea 658 * to try and save a page, but it's a pain in the behind to implement. 659 */ 660 copy_len = filsz == 0 ? 0 : (offset + filsz) - trunc_page(offset + 661 filsz); 662 map_addr = trunc_page((vm_offset_t)vmaddr + filsz); 663 map_len = round_page((vm_offset_t)vmaddr + memsz) - map_addr; 664 665 /* This had damn well better be true! */ 666 if (map_len != 0) { 667 rv = __elfN(map_insert)(imgp, map, NULL, 0, map_addr, 668 map_addr + map_len, prot, 0); 669 if (rv != KERN_SUCCESS) 670 return (EINVAL); 671 } 672 673 if (copy_len != 0) { 674 sf = vm_imgact_map_page(object, offset + filsz); 675 if (sf == NULL) 676 return (EIO); 677 678 /* send the page fragment to user space */ 679 error = copyout((caddr_t)sf_buf_kva(sf), (caddr_t)map_addr, 680 copy_len); 681 vm_imgact_unmap_page(sf); 682 if (error != 0) 683 return (error); 684 } 685 686 /* 687 * Remove write access to the page if it was only granted by map_insert 688 * to allow copyout. 689 */ 690 if ((prot & VM_PROT_WRITE) == 0) 691 vm_map_protect(map, trunc_page(map_addr), round_page(map_addr + 692 map_len), prot, 0, VM_MAP_PROTECT_SET_PROT); 693 694 return (0); 695 } 696 697 static int 698 __elfN(load_sections)(struct image_params *imgp, const Elf_Ehdr *hdr, 699 const Elf_Phdr *phdr, u_long rbase, u_long *base_addrp) 700 { 701 vm_prot_t prot; 702 u_long base_addr; 703 bool first; 704 int error, i; 705 706 ASSERT_VOP_LOCKED(imgp->vp, __func__); 707 708 base_addr = 0; 709 first = true; 710 711 for (i = 0; i < hdr->e_phnum; i++) { 712 if (phdr[i].p_type != PT_LOAD || phdr[i].p_memsz == 0) 713 continue; 714 715 /* Loadable segment */ 716 prot = __elfN(trans_prot)(phdr[i].p_flags); 717 error = __elfN(load_section)(imgp, phdr[i].p_offset, 718 (caddr_t)(uintptr_t)phdr[i].p_vaddr + rbase, 719 phdr[i].p_memsz, phdr[i].p_filesz, prot); 720 if (error != 0) 721 return (error); 722 723 /* 724 * Establish the base address if this is the first segment. 725 */ 726 if (first) { 727 base_addr = trunc_page(phdr[i].p_vaddr + rbase); 728 first = false; 729 } 730 } 731 732 if (base_addrp != NULL) 733 *base_addrp = base_addr; 734 735 return (0); 736 } 737 738 /* 739 * Load the file "file" into memory. It may be either a shared object 740 * or an executable. 741 * 742 * The "addr" reference parameter is in/out. On entry, it specifies 743 * the address where a shared object should be loaded. If the file is 744 * an executable, this value is ignored. On exit, "addr" specifies 745 * where the file was actually loaded. 746 * 747 * The "entry" reference parameter is out only. On exit, it specifies 748 * the entry point for the loaded file. 749 */ 750 static int 751 __elfN(load_file)(struct proc *p, const char *file, u_long *addr, 752 u_long *entry) 753 { 754 struct { 755 struct nameidata nd; 756 struct vattr attr; 757 struct image_params image_params; 758 } *tempdata; 759 const Elf_Ehdr *hdr = NULL; 760 const Elf_Phdr *phdr = NULL; 761 struct nameidata *nd; 762 struct vattr *attr; 763 struct image_params *imgp; 764 u_long rbase; 765 u_long base_addr = 0; 766 int error; 767 768 #ifdef CAPABILITY_MODE 769 /* 770 * XXXJA: This check can go away once we are sufficiently confident 771 * that the checks in namei() are correct. 772 */ 773 if (IN_CAPABILITY_MODE(curthread)) 774 return (ECAPMODE); 775 #endif 776 777 tempdata = malloc(sizeof(*tempdata), M_TEMP, M_WAITOK | M_ZERO); 778 nd = &tempdata->nd; 779 attr = &tempdata->attr; 780 imgp = &tempdata->image_params; 781 782 /* 783 * Initialize part of the common data 784 */ 785 imgp->proc = p; 786 imgp->attr = attr; 787 788 NDINIT(nd, LOOKUP, ISOPEN | FOLLOW | LOCKSHARED | LOCKLEAF, 789 UIO_SYSSPACE, file, curthread); 790 if ((error = namei(nd)) != 0) { 791 nd->ni_vp = NULL; 792 goto fail; 793 } 794 NDFREE(nd, NDF_ONLY_PNBUF); 795 imgp->vp = nd->ni_vp; 796 797 /* 798 * Check permissions, modes, uid, etc on the file, and "open" it. 799 */ 800 error = exec_check_permissions(imgp); 801 if (error) 802 goto fail; 803 804 error = exec_map_first_page(imgp); 805 if (error) 806 goto fail; 807 808 imgp->object = nd->ni_vp->v_object; 809 810 hdr = (const Elf_Ehdr *)imgp->image_header; 811 if ((error = __elfN(check_header)(hdr)) != 0) 812 goto fail; 813 if (hdr->e_type == ET_DYN) 814 rbase = *addr; 815 else if (hdr->e_type == ET_EXEC) 816 rbase = 0; 817 else { 818 error = ENOEXEC; 819 goto fail; 820 } 821 822 /* Only support headers that fit within first page for now */ 823 if (!__elfN(phdr_in_zero_page)(hdr)) { 824 error = ENOEXEC; 825 goto fail; 826 } 827 828 phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff); 829 if (!aligned(phdr, Elf_Addr)) { 830 error = ENOEXEC; 831 goto fail; 832 } 833 834 error = __elfN(load_sections)(imgp, hdr, phdr, rbase, &base_addr); 835 if (error != 0) 836 goto fail; 837 838 *addr = base_addr; 839 *entry = (unsigned long)hdr->e_entry + rbase; 840 841 fail: 842 if (imgp->firstpage) 843 exec_unmap_first_page(imgp); 844 845 if (nd->ni_vp) { 846 if (imgp->textset) 847 VOP_UNSET_TEXT_CHECKED(nd->ni_vp); 848 vput(nd->ni_vp); 849 } 850 free(tempdata, M_TEMP); 851 852 return (error); 853 } 854 855 static u_long 856 __CONCAT(rnd_, __elfN(base))(vm_map_t map __unused, u_long minv, u_long maxv, 857 u_int align) 858 { 859 u_long rbase, res; 860 861 MPASS(vm_map_min(map) <= minv); 862 MPASS(maxv <= vm_map_max(map)); 863 MPASS(minv < maxv); 864 MPASS(minv + align < maxv); 865 arc4rand(&rbase, sizeof(rbase), 0); 866 res = roundup(minv, (u_long)align) + rbase % (maxv - minv); 867 res &= ~((u_long)align - 1); 868 if (res >= maxv) 869 res -= align; 870 KASSERT(res >= minv, 871 ("res %#lx < minv %#lx, maxv %#lx rbase %#lx", 872 res, minv, maxv, rbase)); 873 KASSERT(res < maxv, 874 ("res %#lx > maxv %#lx, minv %#lx rbase %#lx", 875 res, maxv, minv, rbase)); 876 return (res); 877 } 878 879 static int 880 __elfN(enforce_limits)(struct image_params *imgp, const Elf_Ehdr *hdr, 881 const Elf_Phdr *phdr, u_long et_dyn_addr) 882 { 883 struct vmspace *vmspace; 884 const char *err_str; 885 u_long text_size, data_size, total_size, text_addr, data_addr; 886 u_long seg_size, seg_addr; 887 int i; 888 889 err_str = NULL; 890 text_size = data_size = total_size = text_addr = data_addr = 0; 891 892 for (i = 0; i < hdr->e_phnum; i++) { 893 if (phdr[i].p_type != PT_LOAD || phdr[i].p_memsz == 0) 894 continue; 895 896 seg_addr = trunc_page(phdr[i].p_vaddr + et_dyn_addr); 897 seg_size = round_page(phdr[i].p_memsz + 898 phdr[i].p_vaddr + et_dyn_addr - seg_addr); 899 900 /* 901 * Make the largest executable segment the official 902 * text segment and all others data. 903 * 904 * Note that obreak() assumes that data_addr + data_size == end 905 * of data load area, and the ELF file format expects segments 906 * to be sorted by address. If multiple data segments exist, 907 * the last one will be used. 908 */ 909 910 if ((phdr[i].p_flags & PF_X) != 0 && text_size < seg_size) { 911 text_size = seg_size; 912 text_addr = seg_addr; 913 } else { 914 data_size = seg_size; 915 data_addr = seg_addr; 916 } 917 total_size += seg_size; 918 } 919 920 if (data_addr == 0 && data_size == 0) { 921 data_addr = text_addr; 922 data_size = text_size; 923 } 924 925 /* 926 * Check limits. It should be safe to check the 927 * limits after loading the segments since we do 928 * not actually fault in all the segments pages. 929 */ 930 PROC_LOCK(imgp->proc); 931 if (data_size > lim_cur_proc(imgp->proc, RLIMIT_DATA)) 932 err_str = "Data segment size exceeds process limit"; 933 else if (text_size > maxtsiz) 934 err_str = "Text segment size exceeds system limit"; 935 else if (total_size > lim_cur_proc(imgp->proc, RLIMIT_VMEM)) 936 err_str = "Total segment size exceeds process limit"; 937 else if (racct_set(imgp->proc, RACCT_DATA, data_size) != 0) 938 err_str = "Data segment size exceeds resource limit"; 939 else if (racct_set(imgp->proc, RACCT_VMEM, total_size) != 0) 940 err_str = "Total segment size exceeds resource limit"; 941 PROC_UNLOCK(imgp->proc); 942 if (err_str != NULL) { 943 uprintf("%s\n", err_str); 944 return (ENOMEM); 945 } 946 947 vmspace = imgp->proc->p_vmspace; 948 vmspace->vm_tsize = text_size >> PAGE_SHIFT; 949 vmspace->vm_taddr = (caddr_t)(uintptr_t)text_addr; 950 vmspace->vm_dsize = data_size >> PAGE_SHIFT; 951 vmspace->vm_daddr = (caddr_t)(uintptr_t)data_addr; 952 953 return (0); 954 } 955 956 static int 957 __elfN(get_interp)(struct image_params *imgp, const Elf_Phdr *phdr, 958 char **interpp, bool *free_interpp) 959 { 960 struct thread *td; 961 char *interp; 962 int error, interp_name_len; 963 964 KASSERT(phdr->p_type == PT_INTERP, 965 ("%s: p_type %u != PT_INTERP", __func__, phdr->p_type)); 966 ASSERT_VOP_LOCKED(imgp->vp, __func__); 967 968 td = curthread; 969 970 /* Path to interpreter */ 971 if (phdr->p_filesz < 2 || phdr->p_filesz > MAXPATHLEN) { 972 uprintf("Invalid PT_INTERP\n"); 973 return (ENOEXEC); 974 } 975 976 interp_name_len = phdr->p_filesz; 977 if (phdr->p_offset > PAGE_SIZE || 978 interp_name_len > PAGE_SIZE - phdr->p_offset) { 979 /* 980 * The vnode lock might be needed by the pagedaemon to 981 * clean pages owned by the vnode. Do not allow sleep 982 * waiting for memory with the vnode locked, instead 983 * try non-sleepable allocation first, and if it 984 * fails, go to the slow path were we drop the lock 985 * and do M_WAITOK. A text reference prevents 986 * modifications to the vnode content. 987 */ 988 interp = malloc(interp_name_len + 1, M_TEMP, M_NOWAIT); 989 if (interp == NULL) { 990 VOP_UNLOCK(imgp->vp); 991 interp = malloc(interp_name_len + 1, M_TEMP, M_WAITOK); 992 vn_lock(imgp->vp, LK_SHARED | LK_RETRY); 993 } 994 995 error = vn_rdwr(UIO_READ, imgp->vp, interp, 996 interp_name_len, phdr->p_offset, 997 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, 998 NOCRED, NULL, td); 999 if (error != 0) { 1000 free(interp, M_TEMP); 1001 uprintf("i/o error PT_INTERP %d\n", error); 1002 return (error); 1003 } 1004 interp[interp_name_len] = '\0'; 1005 1006 *interpp = interp; 1007 *free_interpp = true; 1008 return (0); 1009 } 1010 1011 interp = __DECONST(char *, imgp->image_header) + phdr->p_offset; 1012 if (interp[interp_name_len - 1] != '\0') { 1013 uprintf("Invalid PT_INTERP\n"); 1014 return (ENOEXEC); 1015 } 1016 1017 *interpp = interp; 1018 *free_interpp = false; 1019 return (0); 1020 } 1021 1022 static int 1023 __elfN(load_interp)(struct image_params *imgp, const Elf_Brandinfo *brand_info, 1024 const char *interp, u_long *addr, u_long *entry) 1025 { 1026 char *path; 1027 int error; 1028 1029 if (brand_info->emul_path != NULL && 1030 brand_info->emul_path[0] != '\0') { 1031 path = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1032 snprintf(path, MAXPATHLEN, "%s%s", 1033 brand_info->emul_path, interp); 1034 error = __elfN(load_file)(imgp->proc, path, addr, entry); 1035 free(path, M_TEMP); 1036 if (error == 0) 1037 return (0); 1038 } 1039 1040 if (brand_info->interp_newpath != NULL && 1041 (brand_info->interp_path == NULL || 1042 strcmp(interp, brand_info->interp_path) == 0)) { 1043 error = __elfN(load_file)(imgp->proc, 1044 brand_info->interp_newpath, addr, entry); 1045 if (error == 0) 1046 return (0); 1047 } 1048 1049 error = __elfN(load_file)(imgp->proc, interp, addr, entry); 1050 if (error == 0) 1051 return (0); 1052 1053 uprintf("ELF interpreter %s not found, error %d\n", interp, error); 1054 return (error); 1055 } 1056 1057 /* 1058 * Impossible et_dyn_addr initial value indicating that the real base 1059 * must be calculated later with some randomization applied. 1060 */ 1061 #define ET_DYN_ADDR_RAND 1 1062 1063 static int 1064 __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp) 1065 { 1066 struct thread *td; 1067 const Elf_Ehdr *hdr; 1068 const Elf_Phdr *phdr; 1069 Elf_Auxargs *elf_auxargs; 1070 struct vmspace *vmspace; 1071 vm_map_t map; 1072 char *interp; 1073 Elf_Brandinfo *brand_info; 1074 struct sysentvec *sv; 1075 u_long addr, baddr, et_dyn_addr, entry, proghdr; 1076 u_long maxalign, mapsz, maxv, maxv1; 1077 uint32_t fctl0; 1078 int32_t osrel; 1079 bool free_interp; 1080 int error, i, n; 1081 1082 hdr = (const Elf_Ehdr *)imgp->image_header; 1083 1084 /* 1085 * Do we have a valid ELF header ? 1086 * 1087 * Only allow ET_EXEC & ET_DYN here, reject ET_DYN later 1088 * if particular brand doesn't support it. 1089 */ 1090 if (__elfN(check_header)(hdr) != 0 || 1091 (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN)) 1092 return (-1); 1093 1094 /* 1095 * From here on down, we return an errno, not -1, as we've 1096 * detected an ELF file. 1097 */ 1098 1099 if (!__elfN(phdr_in_zero_page)(hdr)) { 1100 uprintf("Program headers not in the first page\n"); 1101 return (ENOEXEC); 1102 } 1103 phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff); 1104 if (!aligned(phdr, Elf_Addr)) { 1105 uprintf("Unaligned program headers\n"); 1106 return (ENOEXEC); 1107 } 1108 1109 n = error = 0; 1110 baddr = 0; 1111 osrel = 0; 1112 fctl0 = 0; 1113 entry = proghdr = 0; 1114 interp = NULL; 1115 free_interp = false; 1116 td = curthread; 1117 maxalign = PAGE_SIZE; 1118 mapsz = 0; 1119 1120 for (i = 0; i < hdr->e_phnum; i++) { 1121 switch (phdr[i].p_type) { 1122 case PT_LOAD: 1123 if (n == 0) 1124 baddr = phdr[i].p_vaddr; 1125 if (phdr[i].p_align > maxalign) 1126 maxalign = phdr[i].p_align; 1127 mapsz += phdr[i].p_memsz; 1128 n++; 1129 1130 /* 1131 * If this segment contains the program headers, 1132 * remember their virtual address for the AT_PHDR 1133 * aux entry. Static binaries don't usually include 1134 * a PT_PHDR entry. 1135 */ 1136 if (phdr[i].p_offset == 0 && 1137 hdr->e_phoff + hdr->e_phnum * hdr->e_phentsize 1138 <= phdr[i].p_filesz) 1139 proghdr = phdr[i].p_vaddr + hdr->e_phoff; 1140 break; 1141 case PT_INTERP: 1142 /* Path to interpreter */ 1143 if (interp != NULL) { 1144 uprintf("Multiple PT_INTERP headers\n"); 1145 error = ENOEXEC; 1146 goto ret; 1147 } 1148 error = __elfN(get_interp)(imgp, &phdr[i], &interp, 1149 &free_interp); 1150 if (error != 0) 1151 goto ret; 1152 break; 1153 case PT_GNU_STACK: 1154 if (__elfN(nxstack)) 1155 imgp->stack_prot = 1156 __elfN(trans_prot)(phdr[i].p_flags); 1157 imgp->stack_sz = phdr[i].p_memsz; 1158 break; 1159 case PT_PHDR: /* Program header table info */ 1160 proghdr = phdr[i].p_vaddr; 1161 break; 1162 } 1163 } 1164 1165 brand_info = __elfN(get_brandinfo)(imgp, interp, &osrel, &fctl0); 1166 if (brand_info == NULL) { 1167 uprintf("ELF binary type \"%u\" not known.\n", 1168 hdr->e_ident[EI_OSABI]); 1169 error = ENOEXEC; 1170 goto ret; 1171 } 1172 sv = brand_info->sysvec; 1173 et_dyn_addr = 0; 1174 if (hdr->e_type == ET_DYN) { 1175 if ((brand_info->flags & BI_CAN_EXEC_DYN) == 0) { 1176 uprintf("Cannot execute shared object\n"); 1177 error = ENOEXEC; 1178 goto ret; 1179 } 1180 /* 1181 * Honour the base load address from the dso if it is 1182 * non-zero for some reason. 1183 */ 1184 if (baddr == 0) { 1185 if ((sv->sv_flags & SV_ASLR) == 0 || 1186 (fctl0 & NT_FREEBSD_FCTL_ASLR_DISABLE) != 0) 1187 et_dyn_addr = __elfN(pie_base); 1188 else if ((__elfN(pie_aslr_enabled) && 1189 (imgp->proc->p_flag2 & P2_ASLR_DISABLE) == 0) || 1190 (imgp->proc->p_flag2 & P2_ASLR_ENABLE) != 0) 1191 et_dyn_addr = ET_DYN_ADDR_RAND; 1192 else 1193 et_dyn_addr = __elfN(pie_base); 1194 } 1195 } 1196 1197 /* 1198 * Avoid a possible deadlock if the current address space is destroyed 1199 * and that address space maps the locked vnode. In the common case, 1200 * the locked vnode's v_usecount is decremented but remains greater 1201 * than zero. Consequently, the vnode lock is not needed by vrele(). 1202 * However, in cases where the vnode lock is external, such as nullfs, 1203 * v_usecount may become zero. 1204 * 1205 * The VV_TEXT flag prevents modifications to the executable while 1206 * the vnode is unlocked. 1207 */ 1208 VOP_UNLOCK(imgp->vp); 1209 1210 /* 1211 * Decide whether to enable randomization of user mappings. 1212 * First, reset user preferences for the setid binaries. 1213 * Then, account for the support of the randomization by the 1214 * ABI, by user preferences, and make special treatment for 1215 * PIE binaries. 1216 */ 1217 if (imgp->credential_setid) { 1218 PROC_LOCK(imgp->proc); 1219 imgp->proc->p_flag2 &= ~(P2_ASLR_ENABLE | P2_ASLR_DISABLE); 1220 PROC_UNLOCK(imgp->proc); 1221 } 1222 if ((sv->sv_flags & SV_ASLR) == 0 || 1223 (imgp->proc->p_flag2 & P2_ASLR_DISABLE) != 0 || 1224 (fctl0 & NT_FREEBSD_FCTL_ASLR_DISABLE) != 0) { 1225 KASSERT(et_dyn_addr != ET_DYN_ADDR_RAND, 1226 ("et_dyn_addr == RAND and !ASLR")); 1227 } else if ((imgp->proc->p_flag2 & P2_ASLR_ENABLE) != 0 || 1228 (__elfN(aslr_enabled) && hdr->e_type == ET_EXEC) || 1229 et_dyn_addr == ET_DYN_ADDR_RAND) { 1230 imgp->map_flags |= MAP_ASLR; 1231 /* 1232 * If user does not care about sbrk, utilize the bss 1233 * grow region for mappings as well. We can select 1234 * the base for the image anywere and still not suffer 1235 * from the fragmentation. 1236 */ 1237 if (!__elfN(aslr_honor_sbrk) || 1238 (imgp->proc->p_flag2 & P2_ASLR_IGNSTART) != 0) 1239 imgp->map_flags |= MAP_ASLR_IGNSTART; 1240 } 1241 1242 if (!__elfN(allow_wx) && (fctl0 & NT_FREEBSD_FCTL_WXNEEDED) == 0) 1243 imgp->map_flags |= MAP_WXORX; 1244 1245 error = exec_new_vmspace(imgp, sv); 1246 vmspace = imgp->proc->p_vmspace; 1247 map = &vmspace->vm_map; 1248 1249 imgp->proc->p_sysent = sv; 1250 imgp->proc->p_elf_brandinfo = brand_info; 1251 1252 maxv = vm_map_max(map) - lim_max(td, RLIMIT_STACK); 1253 if (et_dyn_addr == ET_DYN_ADDR_RAND) { 1254 KASSERT((map->flags & MAP_ASLR) != 0, 1255 ("ET_DYN_ADDR_RAND but !MAP_ASLR")); 1256 et_dyn_addr = __CONCAT(rnd_, __elfN(base))(map, 1257 vm_map_min(map) + mapsz + lim_max(td, RLIMIT_DATA), 1258 /* reserve half of the address space to interpreter */ 1259 maxv / 2, 1UL << flsl(maxalign)); 1260 } 1261 1262 vn_lock(imgp->vp, LK_SHARED | LK_RETRY); 1263 if (error != 0) 1264 goto ret; 1265 1266 error = __elfN(load_sections)(imgp, hdr, phdr, et_dyn_addr, NULL); 1267 if (error != 0) 1268 goto ret; 1269 1270 error = __elfN(enforce_limits)(imgp, hdr, phdr, et_dyn_addr); 1271 if (error != 0) 1272 goto ret; 1273 1274 entry = (u_long)hdr->e_entry + et_dyn_addr; 1275 1276 /* 1277 * We load the dynamic linker where a userland call 1278 * to mmap(0, ...) would put it. The rationale behind this 1279 * calculation is that it leaves room for the heap to grow to 1280 * its maximum allowed size. 1281 */ 1282 addr = round_page((vm_offset_t)vmspace->vm_daddr + lim_max(td, 1283 RLIMIT_DATA)); 1284 if ((map->flags & MAP_ASLR) != 0) { 1285 maxv1 = maxv / 2 + addr / 2; 1286 MPASS(maxv1 >= addr); /* No overflow */ 1287 map->anon_loc = __CONCAT(rnd_, __elfN(base))(map, addr, maxv1, 1288 (MAXPAGESIZES > 1 && pagesizes[1] != 0) ? 1289 pagesizes[1] : pagesizes[0]); 1290 } else { 1291 map->anon_loc = addr; 1292 } 1293 1294 imgp->entry_addr = entry; 1295 1296 if (interp != NULL) { 1297 VOP_UNLOCK(imgp->vp); 1298 if ((map->flags & MAP_ASLR) != 0) { 1299 /* Assume that interpreter fits into 1/4 of AS */ 1300 maxv1 = maxv / 2 + addr / 2; 1301 MPASS(maxv1 >= addr); /* No overflow */ 1302 addr = __CONCAT(rnd_, __elfN(base))(map, addr, 1303 maxv1, PAGE_SIZE); 1304 } 1305 error = __elfN(load_interp)(imgp, brand_info, interp, &addr, 1306 &imgp->entry_addr); 1307 vn_lock(imgp->vp, LK_SHARED | LK_RETRY); 1308 if (error != 0) 1309 goto ret; 1310 } else 1311 addr = et_dyn_addr; 1312 1313 /* 1314 * Construct auxargs table (used by the copyout_auxargs routine) 1315 */ 1316 elf_auxargs = malloc(sizeof(Elf_Auxargs), M_TEMP, M_NOWAIT); 1317 if (elf_auxargs == NULL) { 1318 VOP_UNLOCK(imgp->vp); 1319 elf_auxargs = malloc(sizeof(Elf_Auxargs), M_TEMP, M_WAITOK); 1320 vn_lock(imgp->vp, LK_SHARED | LK_RETRY); 1321 } 1322 elf_auxargs->execfd = -1; 1323 elf_auxargs->phdr = proghdr + et_dyn_addr; 1324 elf_auxargs->phent = hdr->e_phentsize; 1325 elf_auxargs->phnum = hdr->e_phnum; 1326 elf_auxargs->pagesz = PAGE_SIZE; 1327 elf_auxargs->base = addr; 1328 elf_auxargs->flags = 0; 1329 elf_auxargs->entry = entry; 1330 elf_auxargs->hdr_eflags = hdr->e_flags; 1331 1332 imgp->auxargs = elf_auxargs; 1333 imgp->interpreted = 0; 1334 imgp->reloc_base = addr; 1335 imgp->proc->p_osrel = osrel; 1336 imgp->proc->p_fctl0 = fctl0; 1337 imgp->proc->p_elf_flags = hdr->e_flags; 1338 1339 ret: 1340 if (free_interp) 1341 free(interp, M_TEMP); 1342 return (error); 1343 } 1344 1345 #define elf_suword __CONCAT(suword, __ELF_WORD_SIZE) 1346 1347 int 1348 __elfN(freebsd_copyout_auxargs)(struct image_params *imgp, uintptr_t base) 1349 { 1350 Elf_Auxargs *args = (Elf_Auxargs *)imgp->auxargs; 1351 Elf_Auxinfo *argarray, *pos; 1352 int error; 1353 1354 argarray = pos = malloc(AT_COUNT * sizeof(*pos), M_TEMP, 1355 M_WAITOK | M_ZERO); 1356 1357 if (args->execfd != -1) 1358 AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd); 1359 AUXARGS_ENTRY(pos, AT_PHDR, args->phdr); 1360 AUXARGS_ENTRY(pos, AT_PHENT, args->phent); 1361 AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum); 1362 AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz); 1363 AUXARGS_ENTRY(pos, AT_FLAGS, args->flags); 1364 AUXARGS_ENTRY(pos, AT_ENTRY, args->entry); 1365 AUXARGS_ENTRY(pos, AT_BASE, args->base); 1366 AUXARGS_ENTRY(pos, AT_EHDRFLAGS, args->hdr_eflags); 1367 if (imgp->execpathp != 0) 1368 AUXARGS_ENTRY_PTR(pos, AT_EXECPATH, imgp->execpathp); 1369 AUXARGS_ENTRY(pos, AT_OSRELDATE, 1370 imgp->proc->p_ucred->cr_prison->pr_osreldate); 1371 if (imgp->canary != 0) { 1372 AUXARGS_ENTRY_PTR(pos, AT_CANARY, imgp->canary); 1373 AUXARGS_ENTRY(pos, AT_CANARYLEN, imgp->canarylen); 1374 } 1375 AUXARGS_ENTRY(pos, AT_NCPUS, mp_ncpus); 1376 if (imgp->pagesizes != 0) { 1377 AUXARGS_ENTRY_PTR(pos, AT_PAGESIZES, imgp->pagesizes); 1378 AUXARGS_ENTRY(pos, AT_PAGESIZESLEN, imgp->pagesizeslen); 1379 } 1380 if (imgp->sysent->sv_timekeep_base != 0) { 1381 AUXARGS_ENTRY(pos, AT_TIMEKEEP, 1382 imgp->sysent->sv_timekeep_base); 1383 } 1384 AUXARGS_ENTRY(pos, AT_STACKPROT, imgp->sysent->sv_shared_page_obj 1385 != NULL && imgp->stack_prot != 0 ? imgp->stack_prot : 1386 imgp->sysent->sv_stackprot); 1387 if (imgp->sysent->sv_hwcap != NULL) 1388 AUXARGS_ENTRY(pos, AT_HWCAP, *imgp->sysent->sv_hwcap); 1389 if (imgp->sysent->sv_hwcap2 != NULL) 1390 AUXARGS_ENTRY(pos, AT_HWCAP2, *imgp->sysent->sv_hwcap2); 1391 AUXARGS_ENTRY(pos, AT_BSDFLAGS, __elfN(sigfastblock) ? 1392 ELF_BSDF_SIGFASTBLK : 0); 1393 AUXARGS_ENTRY(pos, AT_ARGC, imgp->args->argc); 1394 AUXARGS_ENTRY_PTR(pos, AT_ARGV, imgp->argv); 1395 AUXARGS_ENTRY(pos, AT_ENVC, imgp->args->envc); 1396 AUXARGS_ENTRY_PTR(pos, AT_ENVV, imgp->envv); 1397 AUXARGS_ENTRY_PTR(pos, AT_PS_STRINGS, imgp->ps_strings); 1398 if (imgp->sysent->sv_fxrng_gen_base != 0) 1399 AUXARGS_ENTRY(pos, AT_FXRNG, imgp->sysent->sv_fxrng_gen_base); 1400 AUXARGS_ENTRY(pos, AT_NULL, 0); 1401 1402 free(imgp->auxargs, M_TEMP); 1403 imgp->auxargs = NULL; 1404 KASSERT(pos - argarray <= AT_COUNT, ("Too many auxargs")); 1405 1406 error = copyout(argarray, (void *)base, sizeof(*argarray) * AT_COUNT); 1407 free(argarray, M_TEMP); 1408 return (error); 1409 } 1410 1411 int 1412 __elfN(freebsd_fixup)(uintptr_t *stack_base, struct image_params *imgp) 1413 { 1414 Elf_Addr *base; 1415 1416 base = (Elf_Addr *)*stack_base; 1417 base--; 1418 if (elf_suword(base, imgp->args->argc) == -1) 1419 return (EFAULT); 1420 *stack_base = (uintptr_t)base; 1421 return (0); 1422 } 1423 1424 /* 1425 * Code for generating ELF core dumps. 1426 */ 1427 1428 typedef void (*segment_callback)(vm_map_entry_t, void *); 1429 1430 /* Closure for cb_put_phdr(). */ 1431 struct phdr_closure { 1432 Elf_Phdr *phdr; /* Program header to fill in */ 1433 Elf_Off offset; /* Offset of segment in core file */ 1434 }; 1435 1436 struct note_info { 1437 int type; /* Note type. */ 1438 outfunc_t outfunc; /* Output function. */ 1439 void *outarg; /* Argument for the output function. */ 1440 size_t outsize; /* Output size. */ 1441 TAILQ_ENTRY(note_info) link; /* Link to the next note info. */ 1442 }; 1443 1444 TAILQ_HEAD(note_info_list, note_info); 1445 1446 extern int compress_user_cores; 1447 extern int compress_user_cores_level; 1448 1449 static void cb_put_phdr(vm_map_entry_t, void *); 1450 static void cb_size_segment(vm_map_entry_t, void *); 1451 static void each_dumpable_segment(struct thread *, segment_callback, void *, 1452 int); 1453 static int __elfN(corehdr)(struct coredump_params *, int, void *, size_t, 1454 struct note_info_list *, size_t, int); 1455 static void __elfN(putnote)(struct thread *td, struct note_info *, struct sbuf *); 1456 1457 static void __elfN(note_fpregset)(void *, struct sbuf *, size_t *); 1458 static void __elfN(note_prpsinfo)(void *, struct sbuf *, size_t *); 1459 static void __elfN(note_prstatus)(void *, struct sbuf *, size_t *); 1460 static void __elfN(note_threadmd)(void *, struct sbuf *, size_t *); 1461 static void __elfN(note_thrmisc)(void *, struct sbuf *, size_t *); 1462 static void __elfN(note_ptlwpinfo)(void *, struct sbuf *, size_t *); 1463 static void __elfN(note_procstat_auxv)(void *, struct sbuf *, size_t *); 1464 static void __elfN(note_procstat_proc)(void *, struct sbuf *, size_t *); 1465 static void __elfN(note_procstat_psstrings)(void *, struct sbuf *, size_t *); 1466 static void note_procstat_files(void *, struct sbuf *, size_t *); 1467 static void note_procstat_groups(void *, struct sbuf *, size_t *); 1468 static void note_procstat_osrel(void *, struct sbuf *, size_t *); 1469 static void note_procstat_rlimit(void *, struct sbuf *, size_t *); 1470 static void note_procstat_umask(void *, struct sbuf *, size_t *); 1471 static void note_procstat_vmmap(void *, struct sbuf *, size_t *); 1472 1473 static int 1474 core_compressed_write(void *base, size_t len, off_t offset, void *arg) 1475 { 1476 1477 return (core_write((struct coredump_params *)arg, base, len, offset, 1478 UIO_SYSSPACE, NULL)); 1479 } 1480 1481 int 1482 __elfN(coredump)(struct thread *td, struct vnode *vp, off_t limit, int flags) 1483 { 1484 struct ucred *cred = td->td_ucred; 1485 int compm, error = 0; 1486 struct sseg_closure seginfo; 1487 struct note_info_list notelst; 1488 struct coredump_params params; 1489 struct note_info *ninfo; 1490 void *hdr, *tmpbuf; 1491 size_t hdrsize, notesz, coresize; 1492 1493 hdr = NULL; 1494 tmpbuf = NULL; 1495 TAILQ_INIT(¬elst); 1496 1497 /* Size the program segments. */ 1498 __elfN(size_segments)(td, &seginfo, flags); 1499 1500 /* 1501 * Collect info about the core file header area. 1502 */ 1503 hdrsize = sizeof(Elf_Ehdr) + sizeof(Elf_Phdr) * (1 + seginfo.count); 1504 if (seginfo.count + 1 >= PN_XNUM) 1505 hdrsize += sizeof(Elf_Shdr); 1506 td->td_proc->p_sysent->sv_elf_core_prepare_notes(td, ¬elst, ¬esz); 1507 coresize = round_page(hdrsize + notesz) + seginfo.size; 1508 1509 /* Set up core dump parameters. */ 1510 params.offset = 0; 1511 params.active_cred = cred; 1512 params.file_cred = NOCRED; 1513 params.td = td; 1514 params.vp = vp; 1515 params.comp = NULL; 1516 1517 #ifdef RACCT 1518 if (racct_enable) { 1519 PROC_LOCK(td->td_proc); 1520 error = racct_add(td->td_proc, RACCT_CORE, coresize); 1521 PROC_UNLOCK(td->td_proc); 1522 if (error != 0) { 1523 error = EFAULT; 1524 goto done; 1525 } 1526 } 1527 #endif 1528 if (coresize >= limit) { 1529 error = EFAULT; 1530 goto done; 1531 } 1532 1533 /* Create a compression stream if necessary. */ 1534 compm = compress_user_cores; 1535 if ((flags & (SVC_PT_COREDUMP | SVC_NOCOMPRESS)) == SVC_PT_COREDUMP && 1536 compm == 0) 1537 compm = COMPRESS_GZIP; 1538 if (compm != 0) { 1539 params.comp = compressor_init(core_compressed_write, 1540 compm, CORE_BUF_SIZE, 1541 compress_user_cores_level, ¶ms); 1542 if (params.comp == NULL) { 1543 error = EFAULT; 1544 goto done; 1545 } 1546 tmpbuf = malloc(CORE_BUF_SIZE, M_TEMP, M_WAITOK | M_ZERO); 1547 } 1548 1549 /* 1550 * Allocate memory for building the header, fill it up, 1551 * and write it out following the notes. 1552 */ 1553 hdr = malloc(hdrsize, M_TEMP, M_WAITOK); 1554 error = __elfN(corehdr)(¶ms, seginfo.count, hdr, hdrsize, ¬elst, 1555 notesz, flags); 1556 1557 /* Write the contents of all of the writable segments. */ 1558 if (error == 0) { 1559 Elf_Phdr *php; 1560 off_t offset; 1561 int i; 1562 1563 php = (Elf_Phdr *)((char *)hdr + sizeof(Elf_Ehdr)) + 1; 1564 offset = round_page(hdrsize + notesz); 1565 for (i = 0; i < seginfo.count; i++) { 1566 error = core_output((char *)(uintptr_t)php->p_vaddr, 1567 php->p_filesz, offset, ¶ms, tmpbuf); 1568 if (error != 0) 1569 break; 1570 offset += php->p_filesz; 1571 php++; 1572 } 1573 if (error == 0 && params.comp != NULL) 1574 error = compressor_flush(params.comp); 1575 } 1576 if (error) { 1577 log(LOG_WARNING, 1578 "Failed to write core file for process %s (error %d)\n", 1579 curproc->p_comm, error); 1580 } 1581 1582 done: 1583 free(tmpbuf, M_TEMP); 1584 if (params.comp != NULL) 1585 compressor_fini(params.comp); 1586 while ((ninfo = TAILQ_FIRST(¬elst)) != NULL) { 1587 TAILQ_REMOVE(¬elst, ninfo, link); 1588 free(ninfo, M_TEMP); 1589 } 1590 if (hdr != NULL) 1591 free(hdr, M_TEMP); 1592 1593 return (error); 1594 } 1595 1596 /* 1597 * A callback for each_dumpable_segment() to write out the segment's 1598 * program header entry. 1599 */ 1600 static void 1601 cb_put_phdr(vm_map_entry_t entry, void *closure) 1602 { 1603 struct phdr_closure *phc = (struct phdr_closure *)closure; 1604 Elf_Phdr *phdr = phc->phdr; 1605 1606 phc->offset = round_page(phc->offset); 1607 1608 phdr->p_type = PT_LOAD; 1609 phdr->p_offset = phc->offset; 1610 phdr->p_vaddr = entry->start; 1611 phdr->p_paddr = 0; 1612 phdr->p_filesz = phdr->p_memsz = entry->end - entry->start; 1613 phdr->p_align = PAGE_SIZE; 1614 phdr->p_flags = __elfN(untrans_prot)(entry->protection); 1615 1616 phc->offset += phdr->p_filesz; 1617 phc->phdr++; 1618 } 1619 1620 /* 1621 * A callback for each_dumpable_segment() to gather information about 1622 * the number of segments and their total size. 1623 */ 1624 static void 1625 cb_size_segment(vm_map_entry_t entry, void *closure) 1626 { 1627 struct sseg_closure *ssc = (struct sseg_closure *)closure; 1628 1629 ssc->count++; 1630 ssc->size += entry->end - entry->start; 1631 } 1632 1633 void 1634 __elfN(size_segments)(struct thread *td, struct sseg_closure *seginfo, 1635 int flags) 1636 { 1637 seginfo->count = 0; 1638 seginfo->size = 0; 1639 1640 each_dumpable_segment(td, cb_size_segment, seginfo, flags); 1641 } 1642 1643 /* 1644 * For each writable segment in the process's memory map, call the given 1645 * function with a pointer to the map entry and some arbitrary 1646 * caller-supplied data. 1647 */ 1648 static void 1649 each_dumpable_segment(struct thread *td, segment_callback func, void *closure, 1650 int flags) 1651 { 1652 struct proc *p = td->td_proc; 1653 vm_map_t map = &p->p_vmspace->vm_map; 1654 vm_map_entry_t entry; 1655 vm_object_t backing_object, object; 1656 bool ignore_entry; 1657 1658 vm_map_lock_read(map); 1659 VM_MAP_ENTRY_FOREACH(entry, map) { 1660 /* 1661 * Don't dump inaccessible mappings, deal with legacy 1662 * coredump mode. 1663 * 1664 * Note that read-only segments related to the elf binary 1665 * are marked MAP_ENTRY_NOCOREDUMP now so we no longer 1666 * need to arbitrarily ignore such segments. 1667 */ 1668 if ((flags & SVC_ALL) == 0) { 1669 if (elf_legacy_coredump) { 1670 if ((entry->protection & VM_PROT_RW) != 1671 VM_PROT_RW) 1672 continue; 1673 } else { 1674 if ((entry->protection & VM_PROT_ALL) == 0) 1675 continue; 1676 } 1677 } 1678 1679 /* 1680 * Dont include memory segment in the coredump if 1681 * MAP_NOCORE is set in mmap(2) or MADV_NOCORE in 1682 * madvise(2). Do not dump submaps (i.e. parts of the 1683 * kernel map). 1684 */ 1685 if ((entry->eflags & MAP_ENTRY_IS_SUB_MAP) != 0) 1686 continue; 1687 if ((entry->eflags & MAP_ENTRY_NOCOREDUMP) != 0 && 1688 (flags & SVC_ALL) == 0) 1689 continue; 1690 if ((object = entry->object.vm_object) == NULL) 1691 continue; 1692 1693 /* Ignore memory-mapped devices and such things. */ 1694 VM_OBJECT_RLOCK(object); 1695 while ((backing_object = object->backing_object) != NULL) { 1696 VM_OBJECT_RLOCK(backing_object); 1697 VM_OBJECT_RUNLOCK(object); 1698 object = backing_object; 1699 } 1700 ignore_entry = (object->flags & OBJ_FICTITIOUS) != 0; 1701 VM_OBJECT_RUNLOCK(object); 1702 if (ignore_entry) 1703 continue; 1704 1705 (*func)(entry, closure); 1706 } 1707 vm_map_unlock_read(map); 1708 } 1709 1710 /* 1711 * Write the core file header to the file, including padding up to 1712 * the page boundary. 1713 */ 1714 static int 1715 __elfN(corehdr)(struct coredump_params *p, int numsegs, void *hdr, 1716 size_t hdrsize, struct note_info_list *notelst, size_t notesz, 1717 int flags) 1718 { 1719 struct note_info *ninfo; 1720 struct sbuf *sb; 1721 int error; 1722 1723 /* Fill in the header. */ 1724 bzero(hdr, hdrsize); 1725 __elfN(puthdr)(p->td, hdr, hdrsize, numsegs, notesz, flags); 1726 1727 sb = sbuf_new(NULL, NULL, CORE_BUF_SIZE, SBUF_FIXEDLEN); 1728 sbuf_set_drain(sb, sbuf_drain_core_output, p); 1729 sbuf_start_section(sb, NULL); 1730 sbuf_bcat(sb, hdr, hdrsize); 1731 TAILQ_FOREACH(ninfo, notelst, link) 1732 __elfN(putnote)(p->td, ninfo, sb); 1733 /* Align up to a page boundary for the program segments. */ 1734 sbuf_end_section(sb, -1, PAGE_SIZE, 0); 1735 error = sbuf_finish(sb); 1736 sbuf_delete(sb); 1737 1738 return (error); 1739 } 1740 1741 void 1742 __elfN(prepare_notes)(struct thread *td, struct note_info_list *list, 1743 size_t *sizep) 1744 { 1745 struct proc *p; 1746 struct thread *thr; 1747 size_t size; 1748 1749 p = td->td_proc; 1750 size = 0; 1751 1752 size += __elfN(register_note)(td, list, NT_PRPSINFO, __elfN(note_prpsinfo), p); 1753 1754 /* 1755 * To have the debugger select the right thread (LWP) as the initial 1756 * thread, we dump the state of the thread passed to us in td first. 1757 * This is the thread that causes the core dump and thus likely to 1758 * be the right thread one wants to have selected in the debugger. 1759 */ 1760 thr = td; 1761 while (thr != NULL) { 1762 size += __elfN(register_note)(td, list, NT_PRSTATUS, 1763 __elfN(note_prstatus), thr); 1764 size += __elfN(register_note)(td, list, NT_FPREGSET, 1765 __elfN(note_fpregset), thr); 1766 size += __elfN(register_note)(td, list, NT_THRMISC, 1767 __elfN(note_thrmisc), thr); 1768 size += __elfN(register_note)(td, list, NT_PTLWPINFO, 1769 __elfN(note_ptlwpinfo), thr); 1770 size += __elfN(register_note)(td, list, -1, 1771 __elfN(note_threadmd), thr); 1772 1773 thr = thr == td ? TAILQ_FIRST(&p->p_threads) : 1774 TAILQ_NEXT(thr, td_plist); 1775 if (thr == td) 1776 thr = TAILQ_NEXT(thr, td_plist); 1777 } 1778 1779 size += __elfN(register_note)(td, list, NT_PROCSTAT_PROC, 1780 __elfN(note_procstat_proc), p); 1781 size += __elfN(register_note)(td, list, NT_PROCSTAT_FILES, 1782 note_procstat_files, p); 1783 size += __elfN(register_note)(td, list, NT_PROCSTAT_VMMAP, 1784 note_procstat_vmmap, p); 1785 size += __elfN(register_note)(td, list, NT_PROCSTAT_GROUPS, 1786 note_procstat_groups, p); 1787 size += __elfN(register_note)(td, list, NT_PROCSTAT_UMASK, 1788 note_procstat_umask, p); 1789 size += __elfN(register_note)(td, list, NT_PROCSTAT_RLIMIT, 1790 note_procstat_rlimit, p); 1791 size += __elfN(register_note)(td, list, NT_PROCSTAT_OSREL, 1792 note_procstat_osrel, p); 1793 size += __elfN(register_note)(td, list, NT_PROCSTAT_PSSTRINGS, 1794 __elfN(note_procstat_psstrings), p); 1795 size += __elfN(register_note)(td, list, NT_PROCSTAT_AUXV, 1796 __elfN(note_procstat_auxv), p); 1797 1798 *sizep = size; 1799 } 1800 1801 void 1802 __elfN(puthdr)(struct thread *td, void *hdr, size_t hdrsize, int numsegs, 1803 size_t notesz, int flags) 1804 { 1805 Elf_Ehdr *ehdr; 1806 Elf_Phdr *phdr; 1807 Elf_Shdr *shdr; 1808 struct phdr_closure phc; 1809 Elf_Brandinfo *bi; 1810 1811 ehdr = (Elf_Ehdr *)hdr; 1812 bi = td->td_proc->p_elf_brandinfo; 1813 1814 ehdr->e_ident[EI_MAG0] = ELFMAG0; 1815 ehdr->e_ident[EI_MAG1] = ELFMAG1; 1816 ehdr->e_ident[EI_MAG2] = ELFMAG2; 1817 ehdr->e_ident[EI_MAG3] = ELFMAG3; 1818 ehdr->e_ident[EI_CLASS] = ELF_CLASS; 1819 ehdr->e_ident[EI_DATA] = ELF_DATA; 1820 ehdr->e_ident[EI_VERSION] = EV_CURRENT; 1821 ehdr->e_ident[EI_OSABI] = td->td_proc->p_sysent->sv_elf_core_osabi; 1822 ehdr->e_ident[EI_ABIVERSION] = 0; 1823 ehdr->e_ident[EI_PAD] = 0; 1824 ehdr->e_type = ET_CORE; 1825 ehdr->e_machine = bi->machine; 1826 ehdr->e_version = EV_CURRENT; 1827 ehdr->e_entry = 0; 1828 ehdr->e_phoff = sizeof(Elf_Ehdr); 1829 ehdr->e_flags = td->td_proc->p_elf_flags; 1830 ehdr->e_ehsize = sizeof(Elf_Ehdr); 1831 ehdr->e_phentsize = sizeof(Elf_Phdr); 1832 ehdr->e_shentsize = sizeof(Elf_Shdr); 1833 ehdr->e_shstrndx = SHN_UNDEF; 1834 if (numsegs + 1 < PN_XNUM) { 1835 ehdr->e_phnum = numsegs + 1; 1836 ehdr->e_shnum = 0; 1837 } else { 1838 ehdr->e_phnum = PN_XNUM; 1839 ehdr->e_shnum = 1; 1840 1841 ehdr->e_shoff = ehdr->e_phoff + 1842 (numsegs + 1) * ehdr->e_phentsize; 1843 KASSERT(ehdr->e_shoff == hdrsize - sizeof(Elf_Shdr), 1844 ("e_shoff: %zu, hdrsize - shdr: %zu", 1845 (size_t)ehdr->e_shoff, hdrsize - sizeof(Elf_Shdr))); 1846 1847 shdr = (Elf_Shdr *)((char *)hdr + ehdr->e_shoff); 1848 memset(shdr, 0, sizeof(*shdr)); 1849 /* 1850 * A special first section is used to hold large segment and 1851 * section counts. This was proposed by Sun Microsystems in 1852 * Solaris and has been adopted by Linux; the standard ELF 1853 * tools are already familiar with the technique. 1854 * 1855 * See table 7-7 of the Solaris "Linker and Libraries Guide" 1856 * (or 12-7 depending on the version of the document) for more 1857 * details. 1858 */ 1859 shdr->sh_type = SHT_NULL; 1860 shdr->sh_size = ehdr->e_shnum; 1861 shdr->sh_link = ehdr->e_shstrndx; 1862 shdr->sh_info = numsegs + 1; 1863 } 1864 1865 /* 1866 * Fill in the program header entries. 1867 */ 1868 phdr = (Elf_Phdr *)((char *)hdr + ehdr->e_phoff); 1869 1870 /* The note segement. */ 1871 phdr->p_type = PT_NOTE; 1872 phdr->p_offset = hdrsize; 1873 phdr->p_vaddr = 0; 1874 phdr->p_paddr = 0; 1875 phdr->p_filesz = notesz; 1876 phdr->p_memsz = 0; 1877 phdr->p_flags = PF_R; 1878 phdr->p_align = ELF_NOTE_ROUNDSIZE; 1879 phdr++; 1880 1881 /* All the writable segments from the program. */ 1882 phc.phdr = phdr; 1883 phc.offset = round_page(hdrsize + notesz); 1884 each_dumpable_segment(td, cb_put_phdr, &phc, flags); 1885 } 1886 1887 size_t 1888 __elfN(register_note)(struct thread *td, struct note_info_list *list, 1889 int type, outfunc_t out, void *arg) 1890 { 1891 const struct sysentvec *sv; 1892 struct note_info *ninfo; 1893 size_t size, notesize; 1894 1895 sv = td->td_proc->p_sysent; 1896 size = 0; 1897 out(arg, NULL, &size); 1898 ninfo = malloc(sizeof(*ninfo), M_TEMP, M_ZERO | M_WAITOK); 1899 ninfo->type = type; 1900 ninfo->outfunc = out; 1901 ninfo->outarg = arg; 1902 ninfo->outsize = size; 1903 TAILQ_INSERT_TAIL(list, ninfo, link); 1904 1905 if (type == -1) 1906 return (size); 1907 1908 notesize = sizeof(Elf_Note) + /* note header */ 1909 roundup2(strlen(sv->sv_elf_core_abi_vendor) + 1, ELF_NOTE_ROUNDSIZE) + 1910 /* note name */ 1911 roundup2(size, ELF_NOTE_ROUNDSIZE); /* note description */ 1912 1913 return (notesize); 1914 } 1915 1916 static size_t 1917 append_note_data(const void *src, void *dst, size_t len) 1918 { 1919 size_t padded_len; 1920 1921 padded_len = roundup2(len, ELF_NOTE_ROUNDSIZE); 1922 if (dst != NULL) { 1923 bcopy(src, dst, len); 1924 bzero((char *)dst + len, padded_len - len); 1925 } 1926 return (padded_len); 1927 } 1928 1929 size_t 1930 __elfN(populate_note)(int type, void *src, void *dst, size_t size, void **descp) 1931 { 1932 Elf_Note *note; 1933 char *buf; 1934 size_t notesize; 1935 1936 buf = dst; 1937 if (buf != NULL) { 1938 note = (Elf_Note *)buf; 1939 note->n_namesz = sizeof(FREEBSD_ABI_VENDOR); 1940 note->n_descsz = size; 1941 note->n_type = type; 1942 buf += sizeof(*note); 1943 buf += append_note_data(FREEBSD_ABI_VENDOR, buf, 1944 sizeof(FREEBSD_ABI_VENDOR)); 1945 append_note_data(src, buf, size); 1946 if (descp != NULL) 1947 *descp = buf; 1948 } 1949 1950 notesize = sizeof(Elf_Note) + /* note header */ 1951 roundup2(sizeof(FREEBSD_ABI_VENDOR), ELF_NOTE_ROUNDSIZE) + 1952 /* note name */ 1953 roundup2(size, ELF_NOTE_ROUNDSIZE); /* note description */ 1954 1955 return (notesize); 1956 } 1957 1958 static void 1959 __elfN(putnote)(struct thread *td, struct note_info *ninfo, struct sbuf *sb) 1960 { 1961 Elf_Note note; 1962 const struct sysentvec *sv; 1963 ssize_t old_len, sect_len; 1964 size_t new_len, descsz, i; 1965 1966 if (ninfo->type == -1) { 1967 ninfo->outfunc(ninfo->outarg, sb, &ninfo->outsize); 1968 return; 1969 } 1970 1971 sv = td->td_proc->p_sysent; 1972 1973 note.n_namesz = strlen(sv->sv_elf_core_abi_vendor) + 1; 1974 note.n_descsz = ninfo->outsize; 1975 note.n_type = ninfo->type; 1976 1977 sbuf_bcat(sb, ¬e, sizeof(note)); 1978 sbuf_start_section(sb, &old_len); 1979 sbuf_bcat(sb, sv->sv_elf_core_abi_vendor, 1980 strlen(sv->sv_elf_core_abi_vendor) + 1); 1981 sbuf_end_section(sb, old_len, ELF_NOTE_ROUNDSIZE, 0); 1982 if (note.n_descsz == 0) 1983 return; 1984 sbuf_start_section(sb, &old_len); 1985 ninfo->outfunc(ninfo->outarg, sb, &ninfo->outsize); 1986 sect_len = sbuf_end_section(sb, old_len, ELF_NOTE_ROUNDSIZE, 0); 1987 if (sect_len < 0) 1988 return; 1989 1990 new_len = (size_t)sect_len; 1991 descsz = roundup(note.n_descsz, ELF_NOTE_ROUNDSIZE); 1992 if (new_len < descsz) { 1993 /* 1994 * It is expected that individual note emitters will correctly 1995 * predict their expected output size and fill up to that size 1996 * themselves, padding in a format-specific way if needed. 1997 * However, in case they don't, just do it here with zeros. 1998 */ 1999 for (i = 0; i < descsz - new_len; i++) 2000 sbuf_putc(sb, 0); 2001 } else if (new_len > descsz) { 2002 /* 2003 * We can't always truncate sb -- we may have drained some 2004 * of it already. 2005 */ 2006 KASSERT(new_len == descsz, ("%s: Note type %u changed as we " 2007 "read it (%zu > %zu). Since it is longer than " 2008 "expected, this coredump's notes are corrupt. THIS " 2009 "IS A BUG in the note_procstat routine for type %u.\n", 2010 __func__, (unsigned)note.n_type, new_len, descsz, 2011 (unsigned)note.n_type)); 2012 } 2013 } 2014 2015 /* 2016 * Miscellaneous note out functions. 2017 */ 2018 2019 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32 2020 #include <compat/freebsd32/freebsd32.h> 2021 #include <compat/freebsd32/freebsd32_signal.h> 2022 2023 typedef struct prstatus32 elf_prstatus_t; 2024 typedef struct prpsinfo32 elf_prpsinfo_t; 2025 typedef struct fpreg32 elf_prfpregset_t; 2026 typedef struct fpreg32 elf_fpregset_t; 2027 typedef struct reg32 elf_gregset_t; 2028 typedef struct thrmisc32 elf_thrmisc_t; 2029 #define ELF_KERN_PROC_MASK KERN_PROC_MASK32 2030 typedef struct kinfo_proc32 elf_kinfo_proc_t; 2031 typedef uint32_t elf_ps_strings_t; 2032 #else 2033 typedef prstatus_t elf_prstatus_t; 2034 typedef prpsinfo_t elf_prpsinfo_t; 2035 typedef prfpregset_t elf_prfpregset_t; 2036 typedef prfpregset_t elf_fpregset_t; 2037 typedef gregset_t elf_gregset_t; 2038 typedef thrmisc_t elf_thrmisc_t; 2039 #define ELF_KERN_PROC_MASK 0 2040 typedef struct kinfo_proc elf_kinfo_proc_t; 2041 typedef vm_offset_t elf_ps_strings_t; 2042 #endif 2043 2044 static void 2045 __elfN(note_prpsinfo)(void *arg, struct sbuf *sb, size_t *sizep) 2046 { 2047 struct sbuf sbarg; 2048 size_t len; 2049 char *cp, *end; 2050 struct proc *p; 2051 elf_prpsinfo_t *psinfo; 2052 int error; 2053 2054 p = arg; 2055 if (sb != NULL) { 2056 KASSERT(*sizep == sizeof(*psinfo), ("invalid size")); 2057 psinfo = malloc(sizeof(*psinfo), M_TEMP, M_ZERO | M_WAITOK); 2058 psinfo->pr_version = PRPSINFO_VERSION; 2059 psinfo->pr_psinfosz = sizeof(elf_prpsinfo_t); 2060 strlcpy(psinfo->pr_fname, p->p_comm, sizeof(psinfo->pr_fname)); 2061 PROC_LOCK(p); 2062 if (p->p_args != NULL) { 2063 len = sizeof(psinfo->pr_psargs) - 1; 2064 if (len > p->p_args->ar_length) 2065 len = p->p_args->ar_length; 2066 memcpy(psinfo->pr_psargs, p->p_args->ar_args, len); 2067 PROC_UNLOCK(p); 2068 error = 0; 2069 } else { 2070 _PHOLD(p); 2071 PROC_UNLOCK(p); 2072 sbuf_new(&sbarg, psinfo->pr_psargs, 2073 sizeof(psinfo->pr_psargs), SBUF_FIXEDLEN); 2074 error = proc_getargv(curthread, p, &sbarg); 2075 PRELE(p); 2076 if (sbuf_finish(&sbarg) == 0) 2077 len = sbuf_len(&sbarg) - 1; 2078 else 2079 len = sizeof(psinfo->pr_psargs) - 1; 2080 sbuf_delete(&sbarg); 2081 } 2082 if (error || len == 0) 2083 strlcpy(psinfo->pr_psargs, p->p_comm, 2084 sizeof(psinfo->pr_psargs)); 2085 else { 2086 KASSERT(len < sizeof(psinfo->pr_psargs), 2087 ("len is too long: %zu vs %zu", len, 2088 sizeof(psinfo->pr_psargs))); 2089 cp = psinfo->pr_psargs; 2090 end = cp + len - 1; 2091 for (;;) { 2092 cp = memchr(cp, '\0', end - cp); 2093 if (cp == NULL) 2094 break; 2095 *cp = ' '; 2096 } 2097 } 2098 psinfo->pr_pid = p->p_pid; 2099 sbuf_bcat(sb, psinfo, sizeof(*psinfo)); 2100 free(psinfo, M_TEMP); 2101 } 2102 *sizep = sizeof(*psinfo); 2103 } 2104 2105 static void 2106 __elfN(note_prstatus)(void *arg, struct sbuf *sb, size_t *sizep) 2107 { 2108 struct thread *td; 2109 elf_prstatus_t *status; 2110 2111 td = arg; 2112 if (sb != NULL) { 2113 KASSERT(*sizep == sizeof(*status), ("invalid size")); 2114 status = malloc(sizeof(*status), M_TEMP, M_ZERO | M_WAITOK); 2115 status->pr_version = PRSTATUS_VERSION; 2116 status->pr_statussz = sizeof(elf_prstatus_t); 2117 status->pr_gregsetsz = sizeof(elf_gregset_t); 2118 status->pr_fpregsetsz = sizeof(elf_fpregset_t); 2119 status->pr_osreldate = osreldate; 2120 status->pr_cursig = td->td_proc->p_sig; 2121 status->pr_pid = td->td_tid; 2122 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32 2123 fill_regs32(td, &status->pr_reg); 2124 #else 2125 fill_regs(td, &status->pr_reg); 2126 #endif 2127 sbuf_bcat(sb, status, sizeof(*status)); 2128 free(status, M_TEMP); 2129 } 2130 *sizep = sizeof(*status); 2131 } 2132 2133 static void 2134 __elfN(note_fpregset)(void *arg, struct sbuf *sb, size_t *sizep) 2135 { 2136 struct thread *td; 2137 elf_prfpregset_t *fpregset; 2138 2139 td = arg; 2140 if (sb != NULL) { 2141 KASSERT(*sizep == sizeof(*fpregset), ("invalid size")); 2142 fpregset = malloc(sizeof(*fpregset), M_TEMP, M_ZERO | M_WAITOK); 2143 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32 2144 fill_fpregs32(td, fpregset); 2145 #else 2146 fill_fpregs(td, fpregset); 2147 #endif 2148 sbuf_bcat(sb, fpregset, sizeof(*fpregset)); 2149 free(fpregset, M_TEMP); 2150 } 2151 *sizep = sizeof(*fpregset); 2152 } 2153 2154 static void 2155 __elfN(note_thrmisc)(void *arg, struct sbuf *sb, size_t *sizep) 2156 { 2157 struct thread *td; 2158 elf_thrmisc_t thrmisc; 2159 2160 td = arg; 2161 if (sb != NULL) { 2162 KASSERT(*sizep == sizeof(thrmisc), ("invalid size")); 2163 bzero(&thrmisc, sizeof(thrmisc)); 2164 strcpy(thrmisc.pr_tname, td->td_name); 2165 sbuf_bcat(sb, &thrmisc, sizeof(thrmisc)); 2166 } 2167 *sizep = sizeof(thrmisc); 2168 } 2169 2170 static void 2171 __elfN(note_ptlwpinfo)(void *arg, struct sbuf *sb, size_t *sizep) 2172 { 2173 struct thread *td; 2174 size_t size; 2175 int structsize; 2176 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32 2177 struct ptrace_lwpinfo32 pl; 2178 #else 2179 struct ptrace_lwpinfo pl; 2180 #endif 2181 2182 td = arg; 2183 size = sizeof(structsize) + sizeof(pl); 2184 if (sb != NULL) { 2185 KASSERT(*sizep == size, ("invalid size")); 2186 structsize = sizeof(pl); 2187 sbuf_bcat(sb, &structsize, sizeof(structsize)); 2188 bzero(&pl, sizeof(pl)); 2189 pl.pl_lwpid = td->td_tid; 2190 pl.pl_event = PL_EVENT_NONE; 2191 pl.pl_sigmask = td->td_sigmask; 2192 pl.pl_siglist = td->td_siglist; 2193 if (td->td_si.si_signo != 0) { 2194 pl.pl_event = PL_EVENT_SIGNAL; 2195 pl.pl_flags |= PL_FLAG_SI; 2196 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32 2197 siginfo_to_siginfo32(&td->td_si, &pl.pl_siginfo); 2198 #else 2199 pl.pl_siginfo = td->td_si; 2200 #endif 2201 } 2202 strcpy(pl.pl_tdname, td->td_name); 2203 /* XXX TODO: supply more information in struct ptrace_lwpinfo*/ 2204 sbuf_bcat(sb, &pl, sizeof(pl)); 2205 } 2206 *sizep = size; 2207 } 2208 2209 /* 2210 * Allow for MD specific notes, as well as any MD 2211 * specific preparations for writing MI notes. 2212 */ 2213 static void 2214 __elfN(note_threadmd)(void *arg, struct sbuf *sb, size_t *sizep) 2215 { 2216 struct thread *td; 2217 void *buf; 2218 size_t size; 2219 2220 td = (struct thread *)arg; 2221 size = *sizep; 2222 if (size != 0 && sb != NULL) 2223 buf = malloc(size, M_TEMP, M_ZERO | M_WAITOK); 2224 else 2225 buf = NULL; 2226 size = 0; 2227 __elfN(dump_thread)(td, buf, &size); 2228 KASSERT(sb == NULL || *sizep == size, ("invalid size")); 2229 if (size != 0 && sb != NULL) 2230 sbuf_bcat(sb, buf, size); 2231 free(buf, M_TEMP); 2232 *sizep = size; 2233 } 2234 2235 #ifdef KINFO_PROC_SIZE 2236 CTASSERT(sizeof(struct kinfo_proc) == KINFO_PROC_SIZE); 2237 #endif 2238 2239 static void 2240 __elfN(note_procstat_proc)(void *arg, struct sbuf *sb, size_t *sizep) 2241 { 2242 struct proc *p; 2243 size_t size; 2244 int structsize; 2245 2246 p = arg; 2247 size = sizeof(structsize) + p->p_numthreads * 2248 sizeof(elf_kinfo_proc_t); 2249 2250 if (sb != NULL) { 2251 KASSERT(*sizep == size, ("invalid size")); 2252 structsize = sizeof(elf_kinfo_proc_t); 2253 sbuf_bcat(sb, &structsize, sizeof(structsize)); 2254 sx_slock(&proctree_lock); 2255 PROC_LOCK(p); 2256 kern_proc_out(p, sb, ELF_KERN_PROC_MASK); 2257 sx_sunlock(&proctree_lock); 2258 } 2259 *sizep = size; 2260 } 2261 2262 #ifdef KINFO_FILE_SIZE 2263 CTASSERT(sizeof(struct kinfo_file) == KINFO_FILE_SIZE); 2264 #endif 2265 2266 static void 2267 note_procstat_files(void *arg, struct sbuf *sb, size_t *sizep) 2268 { 2269 struct proc *p; 2270 size_t size, sect_sz, i; 2271 ssize_t start_len, sect_len; 2272 int structsize, filedesc_flags; 2273 2274 if (coredump_pack_fileinfo) 2275 filedesc_flags = KERN_FILEDESC_PACK_KINFO; 2276 else 2277 filedesc_flags = 0; 2278 2279 p = arg; 2280 structsize = sizeof(struct kinfo_file); 2281 if (sb == NULL) { 2282 size = 0; 2283 sb = sbuf_new(NULL, NULL, 128, SBUF_FIXEDLEN); 2284 sbuf_set_drain(sb, sbuf_count_drain, &size); 2285 sbuf_bcat(sb, &structsize, sizeof(structsize)); 2286 PROC_LOCK(p); 2287 kern_proc_filedesc_out(p, sb, -1, filedesc_flags); 2288 sbuf_finish(sb); 2289 sbuf_delete(sb); 2290 *sizep = size; 2291 } else { 2292 sbuf_start_section(sb, &start_len); 2293 2294 sbuf_bcat(sb, &structsize, sizeof(structsize)); 2295 PROC_LOCK(p); 2296 kern_proc_filedesc_out(p, sb, *sizep - sizeof(structsize), 2297 filedesc_flags); 2298 2299 sect_len = sbuf_end_section(sb, start_len, 0, 0); 2300 if (sect_len < 0) 2301 return; 2302 sect_sz = sect_len; 2303 2304 KASSERT(sect_sz <= *sizep, 2305 ("kern_proc_filedesc_out did not respect maxlen; " 2306 "requested %zu, got %zu", *sizep - sizeof(structsize), 2307 sect_sz - sizeof(structsize))); 2308 2309 for (i = 0; i < *sizep - sect_sz && sb->s_error == 0; i++) 2310 sbuf_putc(sb, 0); 2311 } 2312 } 2313 2314 #ifdef KINFO_VMENTRY_SIZE 2315 CTASSERT(sizeof(struct kinfo_vmentry) == KINFO_VMENTRY_SIZE); 2316 #endif 2317 2318 static void 2319 note_procstat_vmmap(void *arg, struct sbuf *sb, size_t *sizep) 2320 { 2321 struct proc *p; 2322 size_t size; 2323 int structsize, vmmap_flags; 2324 2325 if (coredump_pack_vmmapinfo) 2326 vmmap_flags = KERN_VMMAP_PACK_KINFO; 2327 else 2328 vmmap_flags = 0; 2329 2330 p = arg; 2331 structsize = sizeof(struct kinfo_vmentry); 2332 if (sb == NULL) { 2333 size = 0; 2334 sb = sbuf_new(NULL, NULL, 128, SBUF_FIXEDLEN); 2335 sbuf_set_drain(sb, sbuf_count_drain, &size); 2336 sbuf_bcat(sb, &structsize, sizeof(structsize)); 2337 PROC_LOCK(p); 2338 kern_proc_vmmap_out(p, sb, -1, vmmap_flags); 2339 sbuf_finish(sb); 2340 sbuf_delete(sb); 2341 *sizep = size; 2342 } else { 2343 sbuf_bcat(sb, &structsize, sizeof(structsize)); 2344 PROC_LOCK(p); 2345 kern_proc_vmmap_out(p, sb, *sizep - sizeof(structsize), 2346 vmmap_flags); 2347 } 2348 } 2349 2350 static void 2351 note_procstat_groups(void *arg, struct sbuf *sb, size_t *sizep) 2352 { 2353 struct proc *p; 2354 size_t size; 2355 int structsize; 2356 2357 p = arg; 2358 size = sizeof(structsize) + p->p_ucred->cr_ngroups * sizeof(gid_t); 2359 if (sb != NULL) { 2360 KASSERT(*sizep == size, ("invalid size")); 2361 structsize = sizeof(gid_t); 2362 sbuf_bcat(sb, &structsize, sizeof(structsize)); 2363 sbuf_bcat(sb, p->p_ucred->cr_groups, p->p_ucred->cr_ngroups * 2364 sizeof(gid_t)); 2365 } 2366 *sizep = size; 2367 } 2368 2369 static void 2370 note_procstat_umask(void *arg, struct sbuf *sb, size_t *sizep) 2371 { 2372 struct proc *p; 2373 size_t size; 2374 int structsize; 2375 2376 p = arg; 2377 size = sizeof(structsize) + sizeof(p->p_pd->pd_cmask); 2378 if (sb != NULL) { 2379 KASSERT(*sizep == size, ("invalid size")); 2380 structsize = sizeof(p->p_pd->pd_cmask); 2381 sbuf_bcat(sb, &structsize, sizeof(structsize)); 2382 sbuf_bcat(sb, &p->p_pd->pd_cmask, sizeof(p->p_pd->pd_cmask)); 2383 } 2384 *sizep = size; 2385 } 2386 2387 static void 2388 note_procstat_rlimit(void *arg, struct sbuf *sb, size_t *sizep) 2389 { 2390 struct proc *p; 2391 struct rlimit rlim[RLIM_NLIMITS]; 2392 size_t size; 2393 int structsize, i; 2394 2395 p = arg; 2396 size = sizeof(structsize) + sizeof(rlim); 2397 if (sb != NULL) { 2398 KASSERT(*sizep == size, ("invalid size")); 2399 structsize = sizeof(rlim); 2400 sbuf_bcat(sb, &structsize, sizeof(structsize)); 2401 PROC_LOCK(p); 2402 for (i = 0; i < RLIM_NLIMITS; i++) 2403 lim_rlimit_proc(p, i, &rlim[i]); 2404 PROC_UNLOCK(p); 2405 sbuf_bcat(sb, rlim, sizeof(rlim)); 2406 } 2407 *sizep = size; 2408 } 2409 2410 static void 2411 note_procstat_osrel(void *arg, struct sbuf *sb, size_t *sizep) 2412 { 2413 struct proc *p; 2414 size_t size; 2415 int structsize; 2416 2417 p = arg; 2418 size = sizeof(structsize) + sizeof(p->p_osrel); 2419 if (sb != NULL) { 2420 KASSERT(*sizep == size, ("invalid size")); 2421 structsize = sizeof(p->p_osrel); 2422 sbuf_bcat(sb, &structsize, sizeof(structsize)); 2423 sbuf_bcat(sb, &p->p_osrel, sizeof(p->p_osrel)); 2424 } 2425 *sizep = size; 2426 } 2427 2428 static void 2429 __elfN(note_procstat_psstrings)(void *arg, struct sbuf *sb, size_t *sizep) 2430 { 2431 struct proc *p; 2432 elf_ps_strings_t ps_strings; 2433 size_t size; 2434 int structsize; 2435 2436 p = arg; 2437 size = sizeof(structsize) + sizeof(ps_strings); 2438 if (sb != NULL) { 2439 KASSERT(*sizep == size, ("invalid size")); 2440 structsize = sizeof(ps_strings); 2441 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32 2442 ps_strings = PTROUT(p->p_sysent->sv_psstrings); 2443 #else 2444 ps_strings = p->p_sysent->sv_psstrings; 2445 #endif 2446 sbuf_bcat(sb, &structsize, sizeof(structsize)); 2447 sbuf_bcat(sb, &ps_strings, sizeof(ps_strings)); 2448 } 2449 *sizep = size; 2450 } 2451 2452 static void 2453 __elfN(note_procstat_auxv)(void *arg, struct sbuf *sb, size_t *sizep) 2454 { 2455 struct proc *p; 2456 size_t size; 2457 int structsize; 2458 2459 p = arg; 2460 if (sb == NULL) { 2461 size = 0; 2462 sb = sbuf_new(NULL, NULL, AT_COUNT * sizeof(Elf_Auxinfo), 2463 SBUF_FIXEDLEN); 2464 sbuf_set_drain(sb, sbuf_count_drain, &size); 2465 sbuf_bcat(sb, &structsize, sizeof(structsize)); 2466 PHOLD(p); 2467 proc_getauxv(curthread, p, sb); 2468 PRELE(p); 2469 sbuf_finish(sb); 2470 sbuf_delete(sb); 2471 *sizep = size; 2472 } else { 2473 structsize = sizeof(Elf_Auxinfo); 2474 sbuf_bcat(sb, &structsize, sizeof(structsize)); 2475 PHOLD(p); 2476 proc_getauxv(curthread, p, sb); 2477 PRELE(p); 2478 } 2479 } 2480 2481 static boolean_t 2482 __elfN(parse_notes)(struct image_params *imgp, Elf_Note *checknote, 2483 const char *note_vendor, const Elf_Phdr *pnote, 2484 boolean_t (*cb)(const Elf_Note *, void *, boolean_t *), void *cb_arg) 2485 { 2486 const Elf_Note *note, *note0, *note_end; 2487 const char *note_name; 2488 char *buf; 2489 int i, error; 2490 boolean_t res; 2491 2492 /* We need some limit, might as well use PAGE_SIZE. */ 2493 if (pnote == NULL || pnote->p_filesz > PAGE_SIZE) 2494 return (FALSE); 2495 ASSERT_VOP_LOCKED(imgp->vp, "parse_notes"); 2496 if (pnote->p_offset > PAGE_SIZE || 2497 pnote->p_filesz > PAGE_SIZE - pnote->p_offset) { 2498 buf = malloc(pnote->p_filesz, M_TEMP, M_NOWAIT); 2499 if (buf == NULL) { 2500 VOP_UNLOCK(imgp->vp); 2501 buf = malloc(pnote->p_filesz, M_TEMP, M_WAITOK); 2502 vn_lock(imgp->vp, LK_SHARED | LK_RETRY); 2503 } 2504 error = vn_rdwr(UIO_READ, imgp->vp, buf, pnote->p_filesz, 2505 pnote->p_offset, UIO_SYSSPACE, IO_NODELOCKED, 2506 curthread->td_ucred, NOCRED, NULL, curthread); 2507 if (error != 0) { 2508 uprintf("i/o error PT_NOTE\n"); 2509 goto retf; 2510 } 2511 note = note0 = (const Elf_Note *)buf; 2512 note_end = (const Elf_Note *)(buf + pnote->p_filesz); 2513 } else { 2514 note = note0 = (const Elf_Note *)(imgp->image_header + 2515 pnote->p_offset); 2516 note_end = (const Elf_Note *)(imgp->image_header + 2517 pnote->p_offset + pnote->p_filesz); 2518 buf = NULL; 2519 } 2520 for (i = 0; i < 100 && note >= note0 && note < note_end; i++) { 2521 if (!aligned(note, Elf32_Addr) || (const char *)note_end - 2522 (const char *)note < sizeof(Elf_Note)) { 2523 goto retf; 2524 } 2525 if (note->n_namesz != checknote->n_namesz || 2526 note->n_descsz != checknote->n_descsz || 2527 note->n_type != checknote->n_type) 2528 goto nextnote; 2529 note_name = (const char *)(note + 1); 2530 if (note_name + checknote->n_namesz >= 2531 (const char *)note_end || strncmp(note_vendor, 2532 note_name, checknote->n_namesz) != 0) 2533 goto nextnote; 2534 2535 if (cb(note, cb_arg, &res)) 2536 goto ret; 2537 nextnote: 2538 note = (const Elf_Note *)((const char *)(note + 1) + 2539 roundup2(note->n_namesz, ELF_NOTE_ROUNDSIZE) + 2540 roundup2(note->n_descsz, ELF_NOTE_ROUNDSIZE)); 2541 } 2542 retf: 2543 res = FALSE; 2544 ret: 2545 free(buf, M_TEMP); 2546 return (res); 2547 } 2548 2549 struct brandnote_cb_arg { 2550 Elf_Brandnote *brandnote; 2551 int32_t *osrel; 2552 }; 2553 2554 static boolean_t 2555 brandnote_cb(const Elf_Note *note, void *arg0, boolean_t *res) 2556 { 2557 struct brandnote_cb_arg *arg; 2558 2559 arg = arg0; 2560 2561 /* 2562 * Fetch the osreldate for binary from the ELF OSABI-note if 2563 * necessary. 2564 */ 2565 *res = (arg->brandnote->flags & BN_TRANSLATE_OSREL) != 0 && 2566 arg->brandnote->trans_osrel != NULL ? 2567 arg->brandnote->trans_osrel(note, arg->osrel) : TRUE; 2568 2569 return (TRUE); 2570 } 2571 2572 static Elf_Note fctl_note = { 2573 .n_namesz = sizeof(FREEBSD_ABI_VENDOR), 2574 .n_descsz = sizeof(uint32_t), 2575 .n_type = NT_FREEBSD_FEATURE_CTL, 2576 }; 2577 2578 struct fctl_cb_arg { 2579 boolean_t *has_fctl0; 2580 uint32_t *fctl0; 2581 }; 2582 2583 static boolean_t 2584 note_fctl_cb(const Elf_Note *note, void *arg0, boolean_t *res) 2585 { 2586 struct fctl_cb_arg *arg; 2587 const Elf32_Word *desc; 2588 uintptr_t p; 2589 2590 arg = arg0; 2591 p = (uintptr_t)(note + 1); 2592 p += roundup2(note->n_namesz, ELF_NOTE_ROUNDSIZE); 2593 desc = (const Elf32_Word *)p; 2594 *arg->has_fctl0 = TRUE; 2595 *arg->fctl0 = desc[0]; 2596 *res = TRUE; 2597 return (TRUE); 2598 } 2599 2600 /* 2601 * Try to find the appropriate ABI-note section for checknote, fetch 2602 * the osreldate and feature control flags for binary from the ELF 2603 * OSABI-note. Only the first page of the image is searched, the same 2604 * as for headers. 2605 */ 2606 static boolean_t 2607 __elfN(check_note)(struct image_params *imgp, Elf_Brandnote *brandnote, 2608 int32_t *osrel, boolean_t *has_fctl0, uint32_t *fctl0) 2609 { 2610 const Elf_Phdr *phdr; 2611 const Elf_Ehdr *hdr; 2612 struct brandnote_cb_arg b_arg; 2613 struct fctl_cb_arg f_arg; 2614 int i, j; 2615 2616 hdr = (const Elf_Ehdr *)imgp->image_header; 2617 phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff); 2618 b_arg.brandnote = brandnote; 2619 b_arg.osrel = osrel; 2620 f_arg.has_fctl0 = has_fctl0; 2621 f_arg.fctl0 = fctl0; 2622 2623 for (i = 0; i < hdr->e_phnum; i++) { 2624 if (phdr[i].p_type == PT_NOTE && __elfN(parse_notes)(imgp, 2625 &brandnote->hdr, brandnote->vendor, &phdr[i], brandnote_cb, 2626 &b_arg)) { 2627 for (j = 0; j < hdr->e_phnum; j++) { 2628 if (phdr[j].p_type == PT_NOTE && 2629 __elfN(parse_notes)(imgp, &fctl_note, 2630 FREEBSD_ABI_VENDOR, &phdr[j], 2631 note_fctl_cb, &f_arg)) 2632 break; 2633 } 2634 return (TRUE); 2635 } 2636 } 2637 return (FALSE); 2638 2639 } 2640 2641 /* 2642 * Tell kern_execve.c about it, with a little help from the linker. 2643 */ 2644 static struct execsw __elfN(execsw) = { 2645 .ex_imgact = __CONCAT(exec_, __elfN(imgact)), 2646 .ex_name = __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) 2647 }; 2648 EXEC_SET(__CONCAT(elf, __ELF_WORD_SIZE), __elfN(execsw)); 2649 2650 static vm_prot_t 2651 __elfN(trans_prot)(Elf_Word flags) 2652 { 2653 vm_prot_t prot; 2654 2655 prot = 0; 2656 if (flags & PF_X) 2657 prot |= VM_PROT_EXECUTE; 2658 if (flags & PF_W) 2659 prot |= VM_PROT_WRITE; 2660 if (flags & PF_R) 2661 prot |= VM_PROT_READ; 2662 #if __ELF_WORD_SIZE == 32 && (defined(__amd64__) || defined(__i386__)) 2663 if (i386_read_exec && (flags & PF_R)) 2664 prot |= VM_PROT_EXECUTE; 2665 #endif 2666 return (prot); 2667 } 2668 2669 static Elf_Word 2670 __elfN(untrans_prot)(vm_prot_t prot) 2671 { 2672 Elf_Word flags; 2673 2674 flags = 0; 2675 if (prot & VM_PROT_EXECUTE) 2676 flags |= PF_X; 2677 if (prot & VM_PROT_READ) 2678 flags |= PF_R; 2679 if (prot & VM_PROT_WRITE) 2680 flags |= PF_W; 2681 return (flags); 2682 } 2683 2684 void 2685 __elfN(stackgap)(struct image_params *imgp, uintptr_t *stack_base) 2686 { 2687 uintptr_t range, rbase, gap; 2688 int pct; 2689 2690 pct = __elfN(aslr_stack_gap); 2691 if (pct == 0) 2692 return; 2693 if (pct > 50) 2694 pct = 50; 2695 range = imgp->eff_stack_sz * pct / 100; 2696 arc4rand(&rbase, sizeof(rbase), 0); 2697 gap = rbase % range; 2698 gap &= ~(sizeof(u_long) - 1); 2699 *stack_base -= gap; 2700 } 2701