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 bool __elfN(check_note)(struct image_params *imgp, 101 Elf_Brandnote *checknote, int32_t *osrel, bool *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 defined(__amd64__) 133 static int __elfN(vdso) = 1; 134 SYSCTL_INT(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO, 135 vdso, CTLFLAG_RWTUN, &__elfN(vdso), 0, 136 __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) ": enable vdso preloading"); 137 #else 138 static int __elfN(vdso) = 0; 139 #endif 140 141 #if __ELF_WORD_SIZE == 32 && (defined(__amd64__) || defined(__i386__)) 142 int i386_read_exec = 0; 143 SYSCTL_INT(_kern_elf32, OID_AUTO, read_exec, CTLFLAG_RW, &i386_read_exec, 0, 144 "enable execution from readable segments"); 145 #endif 146 147 static u_long __elfN(pie_base) = ET_DYN_LOAD_ADDR; 148 static int 149 sysctl_pie_base(SYSCTL_HANDLER_ARGS) 150 { 151 u_long val; 152 int error; 153 154 val = __elfN(pie_base); 155 error = sysctl_handle_long(oidp, &val, 0, req); 156 if (error != 0 || req->newptr == NULL) 157 return (error); 158 if ((val & PAGE_MASK) != 0) 159 return (EINVAL); 160 __elfN(pie_base) = val; 161 return (0); 162 } 163 SYSCTL_PROC(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO, pie_base, 164 CTLTYPE_ULONG | CTLFLAG_MPSAFE | CTLFLAG_RW, NULL, 0, 165 sysctl_pie_base, "LU", 166 "PIE load base without randomization"); 167 168 SYSCTL_NODE(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO, aslr, 169 CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 170 ""); 171 #define ASLR_NODE_OID __CONCAT(__CONCAT(_kern_elf, __ELF_WORD_SIZE), _aslr) 172 173 /* 174 * While for 64-bit machines ASLR works properly, there are 175 * still some problems when using 32-bit architectures. For this 176 * reason ASLR is only enabled by default when running native 177 * 64-bit non-PIE executables. 178 */ 179 static int __elfN(aslr_enabled) = __ELF_WORD_SIZE == 64; 180 SYSCTL_INT(ASLR_NODE_OID, OID_AUTO, enable, CTLFLAG_RWTUN, 181 &__elfN(aslr_enabled), 0, 182 __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) 183 ": enable address map randomization"); 184 185 /* 186 * Enable ASLR only for 64-bit PIE binaries by default. 187 */ 188 static int __elfN(pie_aslr_enabled) = __ELF_WORD_SIZE == 64; 189 SYSCTL_INT(ASLR_NODE_OID, OID_AUTO, pie_enable, CTLFLAG_RWTUN, 190 &__elfN(pie_aslr_enabled), 0, 191 __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) 192 ": enable address map randomization for PIE binaries"); 193 194 /* 195 * Sbrk is now deprecated and it can be assumed, that in most 196 * cases it will not be used anyway. This setting is valid only 197 * for the ASLR enabled and allows for utilizing the bss grow region. 198 */ 199 static int __elfN(aslr_honor_sbrk) = 0; 200 SYSCTL_INT(ASLR_NODE_OID, OID_AUTO, honor_sbrk, CTLFLAG_RW, 201 &__elfN(aslr_honor_sbrk), 0, 202 __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) ": assume sbrk is used"); 203 204 static int __elfN(aslr_stack_gap) = 0; 205 SYSCTL_INT(ASLR_NODE_OID, OID_AUTO, stack_gap, CTLFLAG_RW, 206 &__elfN(aslr_stack_gap), 0, 207 __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) 208 ": maximum percentage of main stack to waste on a random gap"); 209 210 static int __elfN(sigfastblock) = 1; 211 SYSCTL_INT(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO, sigfastblock, 212 CTLFLAG_RWTUN, &__elfN(sigfastblock), 0, 213 "enable sigfastblock for new processes"); 214 215 static bool __elfN(allow_wx) = true; 216 SYSCTL_BOOL(__CONCAT(_kern_elf, __ELF_WORD_SIZE), OID_AUTO, allow_wx, 217 CTLFLAG_RWTUN, &__elfN(allow_wx), 0, 218 "Allow pages to be mapped simultaneously writable and executable"); 219 220 static Elf_Brandinfo *elf_brand_list[MAX_BRANDS]; 221 222 #define aligned(a, t) (rounddown2((u_long)(a), sizeof(t)) == (u_long)(a)) 223 224 Elf_Brandnote __elfN(freebsd_brandnote) = { 225 .hdr.n_namesz = sizeof(FREEBSD_ABI_VENDOR), 226 .hdr.n_descsz = sizeof(int32_t), 227 .hdr.n_type = NT_FREEBSD_ABI_TAG, 228 .vendor = FREEBSD_ABI_VENDOR, 229 .flags = BN_TRANSLATE_OSREL, 230 .trans_osrel = __elfN(freebsd_trans_osrel) 231 }; 232 233 static bool 234 __elfN(freebsd_trans_osrel)(const Elf_Note *note, int32_t *osrel) 235 { 236 uintptr_t p; 237 238 p = (uintptr_t)(note + 1); 239 p += roundup2(note->n_namesz, ELF_NOTE_ROUNDSIZE); 240 *osrel = *(const int32_t *)(p); 241 242 return (true); 243 } 244 245 static const char GNU_ABI_VENDOR[] = "GNU"; 246 static int GNU_KFREEBSD_ABI_DESC = 3; 247 248 Elf_Brandnote __elfN(kfreebsd_brandnote) = { 249 .hdr.n_namesz = sizeof(GNU_ABI_VENDOR), 250 .hdr.n_descsz = 16, /* XXX at least 16 */ 251 .hdr.n_type = 1, 252 .vendor = GNU_ABI_VENDOR, 253 .flags = BN_TRANSLATE_OSREL, 254 .trans_osrel = kfreebsd_trans_osrel 255 }; 256 257 static bool 258 kfreebsd_trans_osrel(const Elf_Note *note, int32_t *osrel) 259 { 260 const Elf32_Word *desc; 261 uintptr_t p; 262 263 p = (uintptr_t)(note + 1); 264 p += roundup2(note->n_namesz, ELF_NOTE_ROUNDSIZE); 265 266 desc = (const Elf32_Word *)p; 267 if (desc[0] != GNU_KFREEBSD_ABI_DESC) 268 return (false); 269 270 /* 271 * Debian GNU/kFreeBSD embed the earliest compatible kernel version 272 * (__FreeBSD_version: <major><two digit minor>Rxx) in the LSB way. 273 */ 274 *osrel = desc[1] * 100000 + desc[2] * 1000 + desc[3]; 275 276 return (true); 277 } 278 279 int 280 __elfN(insert_brand_entry)(Elf_Brandinfo *entry) 281 { 282 int i; 283 284 for (i = 0; i < MAX_BRANDS; i++) { 285 if (elf_brand_list[i] == NULL) { 286 elf_brand_list[i] = entry; 287 break; 288 } 289 } 290 if (i == MAX_BRANDS) { 291 printf("WARNING: %s: could not insert brandinfo entry: %p\n", 292 __func__, entry); 293 return (-1); 294 } 295 return (0); 296 } 297 298 int 299 __elfN(remove_brand_entry)(Elf_Brandinfo *entry) 300 { 301 int i; 302 303 for (i = 0; i < MAX_BRANDS; i++) { 304 if (elf_brand_list[i] == entry) { 305 elf_brand_list[i] = NULL; 306 break; 307 } 308 } 309 if (i == MAX_BRANDS) 310 return (-1); 311 return (0); 312 } 313 314 bool 315 __elfN(brand_inuse)(Elf_Brandinfo *entry) 316 { 317 struct proc *p; 318 bool rval = false; 319 320 sx_slock(&allproc_lock); 321 FOREACH_PROC_IN_SYSTEM(p) { 322 if (p->p_sysent == entry->sysvec) { 323 rval = true; 324 break; 325 } 326 } 327 sx_sunlock(&allproc_lock); 328 329 return (rval); 330 } 331 332 static Elf_Brandinfo * 333 __elfN(get_brandinfo)(struct image_params *imgp, const char *interp, 334 int32_t *osrel, uint32_t *fctl0) 335 { 336 const Elf_Ehdr *hdr = (const Elf_Ehdr *)imgp->image_header; 337 Elf_Brandinfo *bi, *bi_m; 338 bool ret, has_fctl0; 339 int i, interp_name_len; 340 341 interp_name_len = interp != NULL ? strlen(interp) + 1 : 0; 342 343 /* 344 * We support four types of branding -- (1) the ELF EI_OSABI field 345 * that SCO added to the ELF spec, (2) FreeBSD 3.x's traditional string 346 * branding w/in the ELF header, (3) path of the `interp_path' 347 * field, and (4) the ".note.ABI-tag" ELF section. 348 */ 349 350 /* Look for an ".note.ABI-tag" ELF section */ 351 bi_m = NULL; 352 for (i = 0; i < MAX_BRANDS; i++) { 353 bi = elf_brand_list[i]; 354 if (bi == NULL) 355 continue; 356 if (interp != NULL && (bi->flags & BI_BRAND_ONLY_STATIC) != 0) 357 continue; 358 if (hdr->e_machine == bi->machine && (bi->flags & 359 (BI_BRAND_NOTE|BI_BRAND_NOTE_MANDATORY)) != 0) { 360 has_fctl0 = false; 361 *fctl0 = 0; 362 *osrel = 0; 363 ret = __elfN(check_note)(imgp, bi->brand_note, osrel, 364 &has_fctl0, fctl0); 365 /* Give brand a chance to veto check_note's guess */ 366 if (ret && bi->header_supported) { 367 ret = bi->header_supported(imgp, osrel, 368 has_fctl0 ? fctl0 : NULL); 369 } 370 /* 371 * If note checker claimed the binary, but the 372 * interpreter path in the image does not 373 * match default one for the brand, try to 374 * search for other brands with the same 375 * interpreter. Either there is better brand 376 * with the right interpreter, or, failing 377 * this, we return first brand which accepted 378 * our note and, optionally, header. 379 */ 380 if (ret && bi_m == NULL && interp != NULL && 381 (bi->interp_path == NULL || 382 (strlen(bi->interp_path) + 1 != interp_name_len || 383 strncmp(interp, bi->interp_path, interp_name_len) 384 != 0))) { 385 bi_m = bi; 386 ret = 0; 387 } 388 if (ret) 389 return (bi); 390 } 391 } 392 if (bi_m != NULL) 393 return (bi_m); 394 395 /* If the executable has a brand, search for it in the brand list. */ 396 for (i = 0; i < MAX_BRANDS; i++) { 397 bi = elf_brand_list[i]; 398 if (bi == NULL || (bi->flags & BI_BRAND_NOTE_MANDATORY) != 0 || 399 (interp != NULL && (bi->flags & BI_BRAND_ONLY_STATIC) != 0)) 400 continue; 401 if (hdr->e_machine == bi->machine && 402 (hdr->e_ident[EI_OSABI] == bi->brand || 403 (bi->compat_3_brand != NULL && 404 strcmp((const char *)&hdr->e_ident[OLD_EI_BRAND], 405 bi->compat_3_brand) == 0))) { 406 /* Looks good, but give brand a chance to veto */ 407 if (bi->header_supported == NULL || 408 bi->header_supported(imgp, NULL, NULL)) { 409 /* 410 * Again, prefer strictly matching 411 * interpreter path. 412 */ 413 if (interp_name_len == 0 && 414 bi->interp_path == NULL) 415 return (bi); 416 if (bi->interp_path != NULL && 417 strlen(bi->interp_path) + 1 == 418 interp_name_len && strncmp(interp, 419 bi->interp_path, interp_name_len) == 0) 420 return (bi); 421 if (bi_m == NULL) 422 bi_m = bi; 423 } 424 } 425 } 426 if (bi_m != NULL) 427 return (bi_m); 428 429 /* No known brand, see if the header is recognized by any brand */ 430 for (i = 0; i < MAX_BRANDS; i++) { 431 bi = elf_brand_list[i]; 432 if (bi == NULL || bi->flags & BI_BRAND_NOTE_MANDATORY || 433 bi->header_supported == NULL) 434 continue; 435 if (hdr->e_machine == bi->machine) { 436 ret = bi->header_supported(imgp, NULL, NULL); 437 if (ret) 438 return (bi); 439 } 440 } 441 442 /* Lacking a known brand, search for a recognized interpreter. */ 443 if (interp != NULL) { 444 for (i = 0; i < MAX_BRANDS; i++) { 445 bi = elf_brand_list[i]; 446 if (bi == NULL || (bi->flags & 447 (BI_BRAND_NOTE_MANDATORY | BI_BRAND_ONLY_STATIC)) 448 != 0) 449 continue; 450 if (hdr->e_machine == bi->machine && 451 bi->interp_path != NULL && 452 /* ELF image p_filesz includes terminating zero */ 453 strlen(bi->interp_path) + 1 == interp_name_len && 454 strncmp(interp, bi->interp_path, interp_name_len) 455 == 0 && (bi->header_supported == NULL || 456 bi->header_supported(imgp, NULL, NULL))) 457 return (bi); 458 } 459 } 460 461 /* Lacking a recognized interpreter, try the default brand */ 462 for (i = 0; i < MAX_BRANDS; i++) { 463 bi = elf_brand_list[i]; 464 if (bi == NULL || (bi->flags & BI_BRAND_NOTE_MANDATORY) != 0 || 465 (interp != NULL && (bi->flags & BI_BRAND_ONLY_STATIC) != 0)) 466 continue; 467 if (hdr->e_machine == bi->machine && 468 __elfN(fallback_brand) == bi->brand && 469 (bi->header_supported == NULL || 470 bi->header_supported(imgp, NULL, NULL))) 471 return (bi); 472 } 473 return (NULL); 474 } 475 476 static bool 477 __elfN(phdr_in_zero_page)(const Elf_Ehdr *hdr) 478 { 479 return (hdr->e_phoff <= PAGE_SIZE && 480 (u_int)hdr->e_phentsize * hdr->e_phnum <= PAGE_SIZE - hdr->e_phoff); 481 } 482 483 static int 484 __elfN(check_header)(const Elf_Ehdr *hdr) 485 { 486 Elf_Brandinfo *bi; 487 int i; 488 489 if (!IS_ELF(*hdr) || 490 hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS || 491 hdr->e_ident[EI_DATA] != ELF_TARG_DATA || 492 hdr->e_ident[EI_VERSION] != EV_CURRENT || 493 hdr->e_phentsize != sizeof(Elf_Phdr) || 494 hdr->e_version != ELF_TARG_VER) 495 return (ENOEXEC); 496 497 /* 498 * Make sure we have at least one brand for this machine. 499 */ 500 501 for (i = 0; i < MAX_BRANDS; i++) { 502 bi = elf_brand_list[i]; 503 if (bi != NULL && bi->machine == hdr->e_machine) 504 break; 505 } 506 if (i == MAX_BRANDS) 507 return (ENOEXEC); 508 509 return (0); 510 } 511 512 static int 513 __elfN(map_partial)(vm_map_t map, vm_object_t object, vm_ooffset_t offset, 514 vm_offset_t start, vm_offset_t end, vm_prot_t prot) 515 { 516 struct sf_buf *sf; 517 int error; 518 vm_offset_t off; 519 520 /* 521 * Create the page if it doesn't exist yet. Ignore errors. 522 */ 523 vm_map_fixed(map, NULL, 0, trunc_page(start), round_page(end) - 524 trunc_page(start), VM_PROT_ALL, VM_PROT_ALL, MAP_CHECK_EXCL); 525 526 /* 527 * Find the page from the underlying object. 528 */ 529 if (object != NULL) { 530 sf = vm_imgact_map_page(object, offset); 531 if (sf == NULL) 532 return (KERN_FAILURE); 533 off = offset - trunc_page(offset); 534 error = copyout((caddr_t)sf_buf_kva(sf) + off, (caddr_t)start, 535 end - start); 536 vm_imgact_unmap_page(sf); 537 if (error != 0) 538 return (KERN_FAILURE); 539 } 540 541 return (KERN_SUCCESS); 542 } 543 544 static int 545 __elfN(map_insert)(struct image_params *imgp, vm_map_t map, vm_object_t object, 546 vm_ooffset_t offset, vm_offset_t start, vm_offset_t end, vm_prot_t prot, 547 int cow) 548 { 549 struct sf_buf *sf; 550 vm_offset_t off; 551 vm_size_t sz; 552 int error, locked, rv; 553 554 if (start != trunc_page(start)) { 555 rv = __elfN(map_partial)(map, object, offset, start, 556 round_page(start), prot); 557 if (rv != KERN_SUCCESS) 558 return (rv); 559 offset += round_page(start) - start; 560 start = round_page(start); 561 } 562 if (end != round_page(end)) { 563 rv = __elfN(map_partial)(map, object, offset + 564 trunc_page(end) - start, trunc_page(end), end, prot); 565 if (rv != KERN_SUCCESS) 566 return (rv); 567 end = trunc_page(end); 568 } 569 if (start >= end) 570 return (KERN_SUCCESS); 571 if ((offset & PAGE_MASK) != 0) { 572 /* 573 * The mapping is not page aligned. This means that we have 574 * to copy the data. 575 */ 576 rv = vm_map_fixed(map, NULL, 0, start, end - start, 577 prot | VM_PROT_WRITE, VM_PROT_ALL, MAP_CHECK_EXCL); 578 if (rv != KERN_SUCCESS) 579 return (rv); 580 if (object == NULL) 581 return (KERN_SUCCESS); 582 for (; start < end; start += sz) { 583 sf = vm_imgact_map_page(object, offset); 584 if (sf == NULL) 585 return (KERN_FAILURE); 586 off = offset - trunc_page(offset); 587 sz = end - start; 588 if (sz > PAGE_SIZE - off) 589 sz = PAGE_SIZE - off; 590 error = copyout((caddr_t)sf_buf_kva(sf) + off, 591 (caddr_t)start, sz); 592 vm_imgact_unmap_page(sf); 593 if (error != 0) 594 return (KERN_FAILURE); 595 offset += sz; 596 } 597 } else { 598 vm_object_reference(object); 599 rv = vm_map_fixed(map, object, offset, start, end - start, 600 prot, VM_PROT_ALL, cow | MAP_CHECK_EXCL | 601 (object != NULL ? MAP_VN_EXEC : 0)); 602 if (rv != KERN_SUCCESS) { 603 locked = VOP_ISLOCKED(imgp->vp); 604 VOP_UNLOCK(imgp->vp); 605 vm_object_deallocate(object); 606 vn_lock(imgp->vp, locked | LK_RETRY); 607 return (rv); 608 } else if (object != NULL) { 609 MPASS(imgp->vp->v_object == object); 610 VOP_SET_TEXT_CHECKED(imgp->vp); 611 } 612 } 613 return (KERN_SUCCESS); 614 } 615 616 static int 617 __elfN(load_section)(struct image_params *imgp, vm_ooffset_t offset, 618 caddr_t vmaddr, size_t memsz, size_t filsz, vm_prot_t prot) 619 { 620 struct sf_buf *sf; 621 size_t map_len; 622 vm_map_t map; 623 vm_object_t object; 624 vm_offset_t map_addr; 625 int error, rv, cow; 626 size_t copy_len; 627 vm_ooffset_t file_addr; 628 629 /* 630 * It's necessary to fail if the filsz + offset taken from the 631 * header is greater than the actual file pager object's size. 632 * If we were to allow this, then the vm_map_find() below would 633 * walk right off the end of the file object and into the ether. 634 * 635 * While I'm here, might as well check for something else that 636 * is invalid: filsz cannot be greater than memsz. 637 */ 638 if ((filsz != 0 && (off_t)filsz + offset > imgp->attr->va_size) || 639 filsz > memsz) { 640 uprintf("elf_load_section: truncated ELF file\n"); 641 return (ENOEXEC); 642 } 643 644 object = imgp->object; 645 map = &imgp->proc->p_vmspace->vm_map; 646 map_addr = trunc_page((vm_offset_t)vmaddr); 647 file_addr = trunc_page(offset); 648 649 /* 650 * We have two choices. We can either clear the data in the last page 651 * of an oversized mapping, or we can start the anon mapping a page 652 * early and copy the initialized data into that first page. We 653 * choose the second. 654 */ 655 if (filsz == 0) 656 map_len = 0; 657 else if (memsz > filsz) 658 map_len = trunc_page(offset + filsz) - file_addr; 659 else 660 map_len = round_page(offset + filsz) - file_addr; 661 662 if (map_len != 0) { 663 /* cow flags: don't dump readonly sections in core */ 664 cow = MAP_COPY_ON_WRITE | MAP_PREFAULT | 665 (prot & VM_PROT_WRITE ? 0 : MAP_DISABLE_COREDUMP); 666 667 rv = __elfN(map_insert)(imgp, map, object, file_addr, 668 map_addr, map_addr + map_len, prot, cow); 669 if (rv != KERN_SUCCESS) 670 return (EINVAL); 671 672 /* we can stop now if we've covered it all */ 673 if (memsz == filsz) 674 return (0); 675 } 676 677 /* 678 * We have to get the remaining bit of the file into the first part 679 * of the oversized map segment. This is normally because the .data 680 * segment in the file is extended to provide bss. It's a neat idea 681 * to try and save a page, but it's a pain in the behind to implement. 682 */ 683 copy_len = filsz == 0 ? 0 : (offset + filsz) - trunc_page(offset + 684 filsz); 685 map_addr = trunc_page((vm_offset_t)vmaddr + filsz); 686 map_len = round_page((vm_offset_t)vmaddr + memsz) - map_addr; 687 688 /* This had damn well better be true! */ 689 if (map_len != 0) { 690 rv = __elfN(map_insert)(imgp, map, NULL, 0, map_addr, 691 map_addr + map_len, prot, 0); 692 if (rv != KERN_SUCCESS) 693 return (EINVAL); 694 } 695 696 if (copy_len != 0) { 697 sf = vm_imgact_map_page(object, offset + filsz); 698 if (sf == NULL) 699 return (EIO); 700 701 /* send the page fragment to user space */ 702 error = copyout((caddr_t)sf_buf_kva(sf), (caddr_t)map_addr, 703 copy_len); 704 vm_imgact_unmap_page(sf); 705 if (error != 0) 706 return (error); 707 } 708 709 /* 710 * Remove write access to the page if it was only granted by map_insert 711 * to allow copyout. 712 */ 713 if ((prot & VM_PROT_WRITE) == 0) 714 vm_map_protect(map, trunc_page(map_addr), round_page(map_addr + 715 map_len), prot, 0, VM_MAP_PROTECT_SET_PROT); 716 717 return (0); 718 } 719 720 static int 721 __elfN(load_sections)(struct image_params *imgp, const Elf_Ehdr *hdr, 722 const Elf_Phdr *phdr, u_long rbase, u_long *base_addrp) 723 { 724 vm_prot_t prot; 725 u_long base_addr; 726 bool first; 727 int error, i; 728 729 ASSERT_VOP_LOCKED(imgp->vp, __func__); 730 731 base_addr = 0; 732 first = true; 733 734 for (i = 0; i < hdr->e_phnum; i++) { 735 if (phdr[i].p_type != PT_LOAD || phdr[i].p_memsz == 0) 736 continue; 737 738 /* Loadable segment */ 739 prot = __elfN(trans_prot)(phdr[i].p_flags); 740 error = __elfN(load_section)(imgp, phdr[i].p_offset, 741 (caddr_t)(uintptr_t)phdr[i].p_vaddr + rbase, 742 phdr[i].p_memsz, phdr[i].p_filesz, prot); 743 if (error != 0) 744 return (error); 745 746 /* 747 * Establish the base address if this is the first segment. 748 */ 749 if (first) { 750 base_addr = trunc_page(phdr[i].p_vaddr + rbase); 751 first = false; 752 } 753 } 754 755 if (base_addrp != NULL) 756 *base_addrp = base_addr; 757 758 return (0); 759 } 760 761 /* 762 * Load the file "file" into memory. It may be either a shared object 763 * or an executable. 764 * 765 * The "addr" reference parameter is in/out. On entry, it specifies 766 * the address where a shared object should be loaded. If the file is 767 * an executable, this value is ignored. On exit, "addr" specifies 768 * where the file was actually loaded. 769 * 770 * The "entry" reference parameter is out only. On exit, it specifies 771 * the entry point for the loaded file. 772 */ 773 static int 774 __elfN(load_file)(struct proc *p, const char *file, u_long *addr, 775 u_long *entry) 776 { 777 struct { 778 struct nameidata nd; 779 struct vattr attr; 780 struct image_params image_params; 781 } *tempdata; 782 const Elf_Ehdr *hdr = NULL; 783 const Elf_Phdr *phdr = NULL; 784 struct nameidata *nd; 785 struct vattr *attr; 786 struct image_params *imgp; 787 u_long rbase; 788 u_long base_addr = 0; 789 int error; 790 791 #ifdef CAPABILITY_MODE 792 /* 793 * XXXJA: This check can go away once we are sufficiently confident 794 * that the checks in namei() are correct. 795 */ 796 if (IN_CAPABILITY_MODE(curthread)) 797 return (ECAPMODE); 798 #endif 799 800 tempdata = malloc(sizeof(*tempdata), M_TEMP, M_WAITOK | M_ZERO); 801 nd = &tempdata->nd; 802 attr = &tempdata->attr; 803 imgp = &tempdata->image_params; 804 805 /* 806 * Initialize part of the common data 807 */ 808 imgp->proc = p; 809 imgp->attr = attr; 810 811 NDINIT(nd, LOOKUP, ISOPEN | FOLLOW | LOCKSHARED | LOCKLEAF, 812 UIO_SYSSPACE, file); 813 if ((error = namei(nd)) != 0) { 814 nd->ni_vp = NULL; 815 goto fail; 816 } 817 NDFREE(nd, NDF_ONLY_PNBUF); 818 imgp->vp = nd->ni_vp; 819 820 /* 821 * Check permissions, modes, uid, etc on the file, and "open" it. 822 */ 823 error = exec_check_permissions(imgp); 824 if (error) 825 goto fail; 826 827 error = exec_map_first_page(imgp); 828 if (error) 829 goto fail; 830 831 imgp->object = nd->ni_vp->v_object; 832 833 hdr = (const Elf_Ehdr *)imgp->image_header; 834 if ((error = __elfN(check_header)(hdr)) != 0) 835 goto fail; 836 if (hdr->e_type == ET_DYN) 837 rbase = *addr; 838 else if (hdr->e_type == ET_EXEC) 839 rbase = 0; 840 else { 841 error = ENOEXEC; 842 goto fail; 843 } 844 845 /* Only support headers that fit within first page for now */ 846 if (!__elfN(phdr_in_zero_page)(hdr)) { 847 error = ENOEXEC; 848 goto fail; 849 } 850 851 phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff); 852 if (!aligned(phdr, Elf_Addr)) { 853 error = ENOEXEC; 854 goto fail; 855 } 856 857 error = __elfN(load_sections)(imgp, hdr, phdr, rbase, &base_addr); 858 if (error != 0) 859 goto fail; 860 861 *addr = base_addr; 862 *entry = (unsigned long)hdr->e_entry + rbase; 863 864 fail: 865 if (imgp->firstpage) 866 exec_unmap_first_page(imgp); 867 868 if (nd->ni_vp) { 869 if (imgp->textset) 870 VOP_UNSET_TEXT_CHECKED(nd->ni_vp); 871 vput(nd->ni_vp); 872 } 873 free(tempdata, M_TEMP); 874 875 return (error); 876 } 877 878 /* 879 * Select randomized valid address in the map map, between minv and 880 * maxv, with specified alignment. The [minv, maxv) range must belong 881 * to the map. Note that function only allocates the address, it is 882 * up to caller to clamp maxv in a way that the final allocation 883 * length fit into the map. 884 * 885 * Result is returned in *resp, error code indicates that arguments 886 * did not pass sanity checks for overflow and range correctness. 887 */ 888 static int 889 __CONCAT(rnd_, __elfN(base))(vm_map_t map, u_long minv, u_long maxv, 890 u_int align, u_long *resp) 891 { 892 u_long rbase, res; 893 894 MPASS(vm_map_min(map) <= minv); 895 896 if (minv >= maxv || minv + align >= maxv || maxv > vm_map_max(map)) { 897 uprintf("Invalid ELF segments layout\n"); 898 return (ENOEXEC); 899 } 900 901 arc4rand(&rbase, sizeof(rbase), 0); 902 res = roundup(minv, (u_long)align) + rbase % (maxv - minv); 903 res &= ~((u_long)align - 1); 904 if (res >= maxv) 905 res -= align; 906 907 KASSERT(res >= minv, 908 ("res %#lx < minv %#lx, maxv %#lx rbase %#lx", 909 res, minv, maxv, rbase)); 910 KASSERT(res < maxv, 911 ("res %#lx > maxv %#lx, minv %#lx rbase %#lx", 912 res, maxv, minv, rbase)); 913 914 *resp = res; 915 return (0); 916 } 917 918 static int 919 __elfN(enforce_limits)(struct image_params *imgp, const Elf_Ehdr *hdr, 920 const Elf_Phdr *phdr, u_long et_dyn_addr) 921 { 922 struct vmspace *vmspace; 923 const char *err_str; 924 u_long text_size, data_size, total_size, text_addr, data_addr; 925 u_long seg_size, seg_addr; 926 int i; 927 928 err_str = NULL; 929 text_size = data_size = total_size = text_addr = data_addr = 0; 930 931 for (i = 0; i < hdr->e_phnum; i++) { 932 if (phdr[i].p_type != PT_LOAD || phdr[i].p_memsz == 0) 933 continue; 934 935 seg_addr = trunc_page(phdr[i].p_vaddr + et_dyn_addr); 936 seg_size = round_page(phdr[i].p_memsz + 937 phdr[i].p_vaddr + et_dyn_addr - seg_addr); 938 939 /* 940 * Make the largest executable segment the official 941 * text segment and all others data. 942 * 943 * Note that obreak() assumes that data_addr + data_size == end 944 * of data load area, and the ELF file format expects segments 945 * to be sorted by address. If multiple data segments exist, 946 * the last one will be used. 947 */ 948 949 if ((phdr[i].p_flags & PF_X) != 0 && text_size < seg_size) { 950 text_size = seg_size; 951 text_addr = seg_addr; 952 } else { 953 data_size = seg_size; 954 data_addr = seg_addr; 955 } 956 total_size += seg_size; 957 } 958 959 if (data_addr == 0 && data_size == 0) { 960 data_addr = text_addr; 961 data_size = text_size; 962 } 963 964 /* 965 * Check limits. It should be safe to check the 966 * limits after loading the segments since we do 967 * not actually fault in all the segments pages. 968 */ 969 PROC_LOCK(imgp->proc); 970 if (data_size > lim_cur_proc(imgp->proc, RLIMIT_DATA)) 971 err_str = "Data segment size exceeds process limit"; 972 else if (text_size > maxtsiz) 973 err_str = "Text segment size exceeds system limit"; 974 else if (total_size > lim_cur_proc(imgp->proc, RLIMIT_VMEM)) 975 err_str = "Total segment size exceeds process limit"; 976 else if (racct_set(imgp->proc, RACCT_DATA, data_size) != 0) 977 err_str = "Data segment size exceeds resource limit"; 978 else if (racct_set(imgp->proc, RACCT_VMEM, total_size) != 0) 979 err_str = "Total segment size exceeds resource limit"; 980 PROC_UNLOCK(imgp->proc); 981 if (err_str != NULL) { 982 uprintf("%s\n", err_str); 983 return (ENOMEM); 984 } 985 986 vmspace = imgp->proc->p_vmspace; 987 vmspace->vm_tsize = text_size >> PAGE_SHIFT; 988 vmspace->vm_taddr = (caddr_t)(uintptr_t)text_addr; 989 vmspace->vm_dsize = data_size >> PAGE_SHIFT; 990 vmspace->vm_daddr = (caddr_t)(uintptr_t)data_addr; 991 992 return (0); 993 } 994 995 static int 996 __elfN(get_interp)(struct image_params *imgp, const Elf_Phdr *phdr, 997 char **interpp, bool *free_interpp) 998 { 999 struct thread *td; 1000 char *interp; 1001 int error, interp_name_len; 1002 1003 KASSERT(phdr->p_type == PT_INTERP, 1004 ("%s: p_type %u != PT_INTERP", __func__, phdr->p_type)); 1005 ASSERT_VOP_LOCKED(imgp->vp, __func__); 1006 1007 td = curthread; 1008 1009 /* Path to interpreter */ 1010 if (phdr->p_filesz < 2 || phdr->p_filesz > MAXPATHLEN) { 1011 uprintf("Invalid PT_INTERP\n"); 1012 return (ENOEXEC); 1013 } 1014 1015 interp_name_len = phdr->p_filesz; 1016 if (phdr->p_offset > PAGE_SIZE || 1017 interp_name_len > PAGE_SIZE - phdr->p_offset) { 1018 /* 1019 * The vnode lock might be needed by the pagedaemon to 1020 * clean pages owned by the vnode. Do not allow sleep 1021 * waiting for memory with the vnode locked, instead 1022 * try non-sleepable allocation first, and if it 1023 * fails, go to the slow path were we drop the lock 1024 * and do M_WAITOK. A text reference prevents 1025 * modifications to the vnode content. 1026 */ 1027 interp = malloc(interp_name_len + 1, M_TEMP, M_NOWAIT); 1028 if (interp == NULL) { 1029 VOP_UNLOCK(imgp->vp); 1030 interp = malloc(interp_name_len + 1, M_TEMP, M_WAITOK); 1031 vn_lock(imgp->vp, LK_SHARED | LK_RETRY); 1032 } 1033 1034 error = vn_rdwr(UIO_READ, imgp->vp, interp, 1035 interp_name_len, phdr->p_offset, 1036 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, 1037 NOCRED, NULL, td); 1038 if (error != 0) { 1039 free(interp, M_TEMP); 1040 uprintf("i/o error PT_INTERP %d\n", error); 1041 return (error); 1042 } 1043 interp[interp_name_len] = '\0'; 1044 1045 *interpp = interp; 1046 *free_interpp = true; 1047 return (0); 1048 } 1049 1050 interp = __DECONST(char *, imgp->image_header) + phdr->p_offset; 1051 if (interp[interp_name_len - 1] != '\0') { 1052 uprintf("Invalid PT_INTERP\n"); 1053 return (ENOEXEC); 1054 } 1055 1056 *interpp = interp; 1057 *free_interpp = false; 1058 return (0); 1059 } 1060 1061 static int 1062 __elfN(load_interp)(struct image_params *imgp, const Elf_Brandinfo *brand_info, 1063 const char *interp, u_long *addr, u_long *entry) 1064 { 1065 char *path; 1066 int error; 1067 1068 if (brand_info->emul_path != NULL && 1069 brand_info->emul_path[0] != '\0') { 1070 path = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 1071 snprintf(path, MAXPATHLEN, "%s%s", 1072 brand_info->emul_path, interp); 1073 error = __elfN(load_file)(imgp->proc, path, addr, entry); 1074 free(path, M_TEMP); 1075 if (error == 0) 1076 return (0); 1077 } 1078 1079 if (brand_info->interp_newpath != NULL && 1080 (brand_info->interp_path == NULL || 1081 strcmp(interp, brand_info->interp_path) == 0)) { 1082 error = __elfN(load_file)(imgp->proc, 1083 brand_info->interp_newpath, addr, entry); 1084 if (error == 0) 1085 return (0); 1086 } 1087 1088 error = __elfN(load_file)(imgp->proc, interp, addr, entry); 1089 if (error == 0) 1090 return (0); 1091 1092 uprintf("ELF interpreter %s not found, error %d\n", interp, error); 1093 return (error); 1094 } 1095 1096 /* 1097 * Impossible et_dyn_addr initial value indicating that the real base 1098 * must be calculated later with some randomization applied. 1099 */ 1100 #define ET_DYN_ADDR_RAND 1 1101 1102 static int 1103 __CONCAT(exec_, __elfN(imgact))(struct image_params *imgp) 1104 { 1105 struct thread *td; 1106 const Elf_Ehdr *hdr; 1107 const Elf_Phdr *phdr; 1108 Elf_Auxargs *elf_auxargs; 1109 struct vmspace *vmspace; 1110 vm_map_t map; 1111 char *interp; 1112 Elf_Brandinfo *brand_info; 1113 struct sysentvec *sv; 1114 u_long addr, baddr, et_dyn_addr, entry, proghdr; 1115 u_long maxalign, maxsalign, mapsz, maxv, maxv1, anon_loc; 1116 uint32_t fctl0; 1117 int32_t osrel; 1118 bool free_interp; 1119 int error, i, n; 1120 1121 hdr = (const Elf_Ehdr *)imgp->image_header; 1122 1123 /* 1124 * Do we have a valid ELF header ? 1125 * 1126 * Only allow ET_EXEC & ET_DYN here, reject ET_DYN later 1127 * if particular brand doesn't support it. 1128 */ 1129 if (__elfN(check_header)(hdr) != 0 || 1130 (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN)) 1131 return (-1); 1132 1133 /* 1134 * From here on down, we return an errno, not -1, as we've 1135 * detected an ELF file. 1136 */ 1137 1138 if (!__elfN(phdr_in_zero_page)(hdr)) { 1139 uprintf("Program headers not in the first page\n"); 1140 return (ENOEXEC); 1141 } 1142 phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff); 1143 if (!aligned(phdr, Elf_Addr)) { 1144 uprintf("Unaligned program headers\n"); 1145 return (ENOEXEC); 1146 } 1147 1148 n = error = 0; 1149 baddr = 0; 1150 osrel = 0; 1151 fctl0 = 0; 1152 entry = proghdr = 0; 1153 interp = NULL; 1154 free_interp = false; 1155 td = curthread; 1156 1157 /* 1158 * Somewhat arbitrary, limit accepted max alignment for the 1159 * loadable segment to the max supported superpage size. Too 1160 * large alignment requests are not useful and are indicators 1161 * of corrupted or outright malicious binary. 1162 */ 1163 maxalign = PAGE_SIZE; 1164 maxsalign = PAGE_SIZE * 1024; 1165 for (i = MAXPAGESIZES - 1; i > 0; i--) { 1166 if (pagesizes[i] > maxsalign) 1167 maxsalign = pagesizes[i]; 1168 } 1169 1170 mapsz = 0; 1171 1172 for (i = 0; i < hdr->e_phnum; i++) { 1173 switch (phdr[i].p_type) { 1174 case PT_LOAD: 1175 if (n == 0) 1176 baddr = phdr[i].p_vaddr; 1177 if (!powerof2(phdr[i].p_align) || 1178 phdr[i].p_align > maxsalign) { 1179 uprintf("Invalid segment alignment\n"); 1180 error = ENOEXEC; 1181 goto ret; 1182 } 1183 if (phdr[i].p_align > maxalign) 1184 maxalign = phdr[i].p_align; 1185 if (mapsz + phdr[i].p_memsz < mapsz) { 1186 uprintf("Mapsize overflow\n"); 1187 error = ENOEXEC; 1188 goto ret; 1189 } 1190 mapsz += phdr[i].p_memsz; 1191 n++; 1192 1193 /* 1194 * If this segment contains the program headers, 1195 * remember their virtual address for the AT_PHDR 1196 * aux entry. Static binaries don't usually include 1197 * a PT_PHDR entry. 1198 */ 1199 if (phdr[i].p_offset == 0 && 1200 hdr->e_phoff + hdr->e_phnum * hdr->e_phentsize <= 1201 phdr[i].p_filesz) 1202 proghdr = phdr[i].p_vaddr + hdr->e_phoff; 1203 break; 1204 case PT_INTERP: 1205 /* Path to interpreter */ 1206 if (interp != NULL) { 1207 uprintf("Multiple PT_INTERP headers\n"); 1208 error = ENOEXEC; 1209 goto ret; 1210 } 1211 error = __elfN(get_interp)(imgp, &phdr[i], &interp, 1212 &free_interp); 1213 if (error != 0) 1214 goto ret; 1215 break; 1216 case PT_GNU_STACK: 1217 if (__elfN(nxstack)) 1218 imgp->stack_prot = 1219 __elfN(trans_prot)(phdr[i].p_flags); 1220 imgp->stack_sz = phdr[i].p_memsz; 1221 break; 1222 case PT_PHDR: /* Program header table info */ 1223 proghdr = phdr[i].p_vaddr; 1224 break; 1225 } 1226 } 1227 1228 brand_info = __elfN(get_brandinfo)(imgp, interp, &osrel, &fctl0); 1229 if (brand_info == NULL) { 1230 uprintf("ELF binary type \"%u\" not known.\n", 1231 hdr->e_ident[EI_OSABI]); 1232 error = ENOEXEC; 1233 goto ret; 1234 } 1235 sv = brand_info->sysvec; 1236 et_dyn_addr = 0; 1237 if (hdr->e_type == ET_DYN) { 1238 if ((brand_info->flags & BI_CAN_EXEC_DYN) == 0) { 1239 uprintf("Cannot execute shared object\n"); 1240 error = ENOEXEC; 1241 goto ret; 1242 } 1243 /* 1244 * Honour the base load address from the dso if it is 1245 * non-zero for some reason. 1246 */ 1247 if (baddr == 0) { 1248 if ((sv->sv_flags & SV_ASLR) == 0 || 1249 (fctl0 & NT_FREEBSD_FCTL_ASLR_DISABLE) != 0) 1250 et_dyn_addr = __elfN(pie_base); 1251 else if ((__elfN(pie_aslr_enabled) && 1252 (imgp->proc->p_flag2 & P2_ASLR_DISABLE) == 0) || 1253 (imgp->proc->p_flag2 & P2_ASLR_ENABLE) != 0) 1254 et_dyn_addr = ET_DYN_ADDR_RAND; 1255 else 1256 et_dyn_addr = __elfN(pie_base); 1257 } 1258 } 1259 1260 /* 1261 * Avoid a possible deadlock if the current address space is destroyed 1262 * and that address space maps the locked vnode. In the common case, 1263 * the locked vnode's v_usecount is decremented but remains greater 1264 * than zero. Consequently, the vnode lock is not needed by vrele(). 1265 * However, in cases where the vnode lock is external, such as nullfs, 1266 * v_usecount may become zero. 1267 * 1268 * The VV_TEXT flag prevents modifications to the executable while 1269 * the vnode is unlocked. 1270 */ 1271 VOP_UNLOCK(imgp->vp); 1272 1273 /* 1274 * Decide whether to enable randomization of user mappings. 1275 * First, reset user preferences for the setid binaries. 1276 * Then, account for the support of the randomization by the 1277 * ABI, by user preferences, and make special treatment for 1278 * PIE binaries. 1279 */ 1280 if (imgp->credential_setid) { 1281 PROC_LOCK(imgp->proc); 1282 imgp->proc->p_flag2 &= ~(P2_ASLR_ENABLE | P2_ASLR_DISABLE | 1283 P2_WXORX_DISABLE | P2_WXORX_ENABLE_EXEC); 1284 PROC_UNLOCK(imgp->proc); 1285 } 1286 if ((sv->sv_flags & SV_ASLR) == 0 || 1287 (imgp->proc->p_flag2 & P2_ASLR_DISABLE) != 0 || 1288 (fctl0 & NT_FREEBSD_FCTL_ASLR_DISABLE) != 0) { 1289 KASSERT(et_dyn_addr != ET_DYN_ADDR_RAND, 1290 ("et_dyn_addr == RAND and !ASLR")); 1291 } else if ((imgp->proc->p_flag2 & P2_ASLR_ENABLE) != 0 || 1292 (__elfN(aslr_enabled) && hdr->e_type == ET_EXEC) || 1293 et_dyn_addr == ET_DYN_ADDR_RAND) { 1294 imgp->map_flags |= MAP_ASLR; 1295 /* 1296 * If user does not care about sbrk, utilize the bss 1297 * grow region for mappings as well. We can select 1298 * the base for the image anywere and still not suffer 1299 * from the fragmentation. 1300 */ 1301 if (!__elfN(aslr_honor_sbrk) || 1302 (imgp->proc->p_flag2 & P2_ASLR_IGNSTART) != 0) 1303 imgp->map_flags |= MAP_ASLR_IGNSTART; 1304 } 1305 1306 if ((!__elfN(allow_wx) && (fctl0 & NT_FREEBSD_FCTL_WXNEEDED) == 0 && 1307 (imgp->proc->p_flag2 & P2_WXORX_DISABLE) == 0) || 1308 (imgp->proc->p_flag2 & P2_WXORX_ENABLE_EXEC) != 0) 1309 imgp->map_flags |= MAP_WXORX; 1310 1311 error = exec_new_vmspace(imgp, sv); 1312 vmspace = imgp->proc->p_vmspace; 1313 map = &vmspace->vm_map; 1314 1315 imgp->proc->p_sysent = sv; 1316 imgp->proc->p_elf_brandinfo = brand_info; 1317 1318 maxv = vm_map_max(map) - lim_max(td, RLIMIT_STACK); 1319 if (mapsz >= maxv - vm_map_min(map)) { 1320 uprintf("Excessive mapping size\n"); 1321 error = ENOEXEC; 1322 } 1323 1324 if (error == 0 && et_dyn_addr == ET_DYN_ADDR_RAND) { 1325 KASSERT((map->flags & MAP_ASLR) != 0, 1326 ("ET_DYN_ADDR_RAND but !MAP_ASLR")); 1327 error = __CONCAT(rnd_, __elfN(base))(map, 1328 vm_map_min(map) + mapsz + lim_max(td, RLIMIT_DATA), 1329 /* reserve half of the address space to interpreter */ 1330 maxv / 2, maxalign, &et_dyn_addr); 1331 } 1332 1333 vn_lock(imgp->vp, LK_SHARED | LK_RETRY); 1334 if (error != 0) 1335 goto ret; 1336 1337 error = __elfN(load_sections)(imgp, hdr, phdr, et_dyn_addr, NULL); 1338 if (error != 0) 1339 goto ret; 1340 1341 error = __elfN(enforce_limits)(imgp, hdr, phdr, et_dyn_addr); 1342 if (error != 0) 1343 goto ret; 1344 1345 entry = (u_long)hdr->e_entry + et_dyn_addr; 1346 1347 /* 1348 * We load the dynamic linker where a userland call 1349 * to mmap(0, ...) would put it. The rationale behind this 1350 * calculation is that it leaves room for the heap to grow to 1351 * its maximum allowed size. 1352 */ 1353 addr = round_page((vm_offset_t)vmspace->vm_daddr + lim_max(td, 1354 RLIMIT_DATA)); 1355 if ((map->flags & MAP_ASLR) != 0) { 1356 maxv1 = maxv / 2 + addr / 2; 1357 error = __CONCAT(rnd_, __elfN(base))(map, addr, maxv1, 1358 (MAXPAGESIZES > 1 && pagesizes[1] != 0) ? 1359 pagesizes[1] : pagesizes[0], &anon_loc); 1360 if (error != 0) 1361 goto ret; 1362 map->anon_loc = anon_loc; 1363 } else { 1364 map->anon_loc = addr; 1365 } 1366 1367 imgp->entry_addr = entry; 1368 1369 if (interp != NULL) { 1370 VOP_UNLOCK(imgp->vp); 1371 if ((map->flags & MAP_ASLR) != 0) { 1372 /* Assume that interpreter fits into 1/4 of AS */ 1373 maxv1 = maxv / 2 + addr / 2; 1374 error = __CONCAT(rnd_, __elfN(base))(map, addr, 1375 maxv1, PAGE_SIZE, &addr); 1376 } 1377 if (error == 0) { 1378 error = __elfN(load_interp)(imgp, brand_info, interp, 1379 &addr, &imgp->entry_addr); 1380 } 1381 vn_lock(imgp->vp, LK_SHARED | LK_RETRY); 1382 if (error != 0) 1383 goto ret; 1384 } else 1385 addr = et_dyn_addr; 1386 1387 /* 1388 * Construct auxargs table (used by the copyout_auxargs routine) 1389 */ 1390 elf_auxargs = malloc(sizeof(Elf_Auxargs), M_TEMP, M_NOWAIT); 1391 if (elf_auxargs == NULL) { 1392 VOP_UNLOCK(imgp->vp); 1393 elf_auxargs = malloc(sizeof(Elf_Auxargs), M_TEMP, M_WAITOK); 1394 vn_lock(imgp->vp, LK_SHARED | LK_RETRY); 1395 } 1396 elf_auxargs->execfd = -1; 1397 elf_auxargs->phdr = proghdr + et_dyn_addr; 1398 elf_auxargs->phent = hdr->e_phentsize; 1399 elf_auxargs->phnum = hdr->e_phnum; 1400 elf_auxargs->pagesz = PAGE_SIZE; 1401 elf_auxargs->base = addr; 1402 elf_auxargs->flags = 0; 1403 elf_auxargs->entry = entry; 1404 elf_auxargs->hdr_eflags = hdr->e_flags; 1405 1406 imgp->auxargs = elf_auxargs; 1407 imgp->interpreted = 0; 1408 imgp->reloc_base = addr; 1409 imgp->proc->p_osrel = osrel; 1410 imgp->proc->p_fctl0 = fctl0; 1411 imgp->proc->p_elf_flags = hdr->e_flags; 1412 1413 ret: 1414 ASSERT_VOP_LOCKED(imgp->vp, "skipped relock"); 1415 if (free_interp) 1416 free(interp, M_TEMP); 1417 return (error); 1418 } 1419 1420 #define elf_suword __CONCAT(suword, __ELF_WORD_SIZE) 1421 1422 int 1423 __elfN(freebsd_copyout_auxargs)(struct image_params *imgp, uintptr_t base) 1424 { 1425 Elf_Auxargs *args = (Elf_Auxargs *)imgp->auxargs; 1426 Elf_Auxinfo *argarray, *pos; 1427 int error; 1428 1429 argarray = pos = malloc(AT_COUNT * sizeof(*pos), M_TEMP, 1430 M_WAITOK | M_ZERO); 1431 1432 if (args->execfd != -1) 1433 AUXARGS_ENTRY(pos, AT_EXECFD, args->execfd); 1434 AUXARGS_ENTRY(pos, AT_PHDR, args->phdr); 1435 AUXARGS_ENTRY(pos, AT_PHENT, args->phent); 1436 AUXARGS_ENTRY(pos, AT_PHNUM, args->phnum); 1437 AUXARGS_ENTRY(pos, AT_PAGESZ, args->pagesz); 1438 AUXARGS_ENTRY(pos, AT_FLAGS, args->flags); 1439 AUXARGS_ENTRY(pos, AT_ENTRY, args->entry); 1440 AUXARGS_ENTRY(pos, AT_BASE, args->base); 1441 AUXARGS_ENTRY(pos, AT_EHDRFLAGS, args->hdr_eflags); 1442 if (imgp->execpathp != 0) 1443 AUXARGS_ENTRY_PTR(pos, AT_EXECPATH, imgp->execpathp); 1444 AUXARGS_ENTRY(pos, AT_OSRELDATE, 1445 imgp->proc->p_ucred->cr_prison->pr_osreldate); 1446 if (imgp->canary != 0) { 1447 AUXARGS_ENTRY_PTR(pos, AT_CANARY, imgp->canary); 1448 AUXARGS_ENTRY(pos, AT_CANARYLEN, imgp->canarylen); 1449 } 1450 AUXARGS_ENTRY(pos, AT_NCPUS, mp_ncpus); 1451 if (imgp->pagesizes != 0) { 1452 AUXARGS_ENTRY_PTR(pos, AT_PAGESIZES, imgp->pagesizes); 1453 AUXARGS_ENTRY(pos, AT_PAGESIZESLEN, imgp->pagesizeslen); 1454 } 1455 if (imgp->sysent->sv_timekeep_base != 0) { 1456 AUXARGS_ENTRY(pos, AT_TIMEKEEP, 1457 imgp->sysent->sv_timekeep_base); 1458 } 1459 AUXARGS_ENTRY(pos, AT_STACKPROT, imgp->sysent->sv_shared_page_obj 1460 != NULL && imgp->stack_prot != 0 ? imgp->stack_prot : 1461 imgp->sysent->sv_stackprot); 1462 if (imgp->sysent->sv_hwcap != NULL) 1463 AUXARGS_ENTRY(pos, AT_HWCAP, *imgp->sysent->sv_hwcap); 1464 if (imgp->sysent->sv_hwcap2 != NULL) 1465 AUXARGS_ENTRY(pos, AT_HWCAP2, *imgp->sysent->sv_hwcap2); 1466 AUXARGS_ENTRY(pos, AT_BSDFLAGS, __elfN(sigfastblock) ? 1467 ELF_BSDF_SIGFASTBLK : 0); 1468 AUXARGS_ENTRY(pos, AT_ARGC, imgp->args->argc); 1469 AUXARGS_ENTRY_PTR(pos, AT_ARGV, imgp->argv); 1470 AUXARGS_ENTRY(pos, AT_ENVC, imgp->args->envc); 1471 AUXARGS_ENTRY_PTR(pos, AT_ENVV, imgp->envv); 1472 AUXARGS_ENTRY_PTR(pos, AT_PS_STRINGS, imgp->ps_strings); 1473 if (imgp->sysent->sv_fxrng_gen_base != 0) 1474 AUXARGS_ENTRY(pos, AT_FXRNG, imgp->sysent->sv_fxrng_gen_base); 1475 if (imgp->sysent->sv_vdso_base != 0 && __elfN(vdso) != 0) 1476 AUXARGS_ENTRY(pos, AT_KPRELOAD, imgp->sysent->sv_vdso_base); 1477 AUXARGS_ENTRY(pos, AT_NULL, 0); 1478 1479 free(imgp->auxargs, M_TEMP); 1480 imgp->auxargs = NULL; 1481 KASSERT(pos - argarray <= AT_COUNT, ("Too many auxargs")); 1482 1483 error = copyout(argarray, (void *)base, sizeof(*argarray) * AT_COUNT); 1484 free(argarray, M_TEMP); 1485 return (error); 1486 } 1487 1488 int 1489 __elfN(freebsd_fixup)(uintptr_t *stack_base, struct image_params *imgp) 1490 { 1491 Elf_Addr *base; 1492 1493 base = (Elf_Addr *)*stack_base; 1494 base--; 1495 if (elf_suword(base, imgp->args->argc) == -1) 1496 return (EFAULT); 1497 *stack_base = (uintptr_t)base; 1498 return (0); 1499 } 1500 1501 /* 1502 * Code for generating ELF core dumps. 1503 */ 1504 1505 typedef void (*segment_callback)(vm_map_entry_t, void *); 1506 1507 /* Closure for cb_put_phdr(). */ 1508 struct phdr_closure { 1509 Elf_Phdr *phdr; /* Program header to fill in */ 1510 Elf_Off offset; /* Offset of segment in core file */ 1511 }; 1512 1513 struct note_info { 1514 int type; /* Note type. */ 1515 outfunc_t outfunc; /* Output function. */ 1516 void *outarg; /* Argument for the output function. */ 1517 size_t outsize; /* Output size. */ 1518 TAILQ_ENTRY(note_info) link; /* Link to the next note info. */ 1519 }; 1520 1521 TAILQ_HEAD(note_info_list, note_info); 1522 1523 extern int compress_user_cores; 1524 extern int compress_user_cores_level; 1525 1526 static void cb_put_phdr(vm_map_entry_t, void *); 1527 static void cb_size_segment(vm_map_entry_t, void *); 1528 static void each_dumpable_segment(struct thread *, segment_callback, void *, 1529 int); 1530 static int __elfN(corehdr)(struct coredump_params *, int, void *, size_t, 1531 struct note_info_list *, size_t, int); 1532 static void __elfN(putnote)(struct thread *td, struct note_info *, struct sbuf *); 1533 1534 static void __elfN(note_fpregset)(void *, struct sbuf *, size_t *); 1535 static void __elfN(note_prpsinfo)(void *, struct sbuf *, size_t *); 1536 static void __elfN(note_prstatus)(void *, struct sbuf *, size_t *); 1537 static void __elfN(note_threadmd)(void *, struct sbuf *, size_t *); 1538 static void __elfN(note_thrmisc)(void *, struct sbuf *, size_t *); 1539 static void __elfN(note_ptlwpinfo)(void *, struct sbuf *, size_t *); 1540 static void __elfN(note_procstat_auxv)(void *, struct sbuf *, size_t *); 1541 static void __elfN(note_procstat_proc)(void *, struct sbuf *, size_t *); 1542 static void __elfN(note_procstat_psstrings)(void *, struct sbuf *, size_t *); 1543 static void note_procstat_files(void *, struct sbuf *, size_t *); 1544 static void note_procstat_groups(void *, struct sbuf *, size_t *); 1545 static void note_procstat_osrel(void *, struct sbuf *, size_t *); 1546 static void note_procstat_rlimit(void *, struct sbuf *, size_t *); 1547 static void note_procstat_umask(void *, struct sbuf *, size_t *); 1548 static void note_procstat_vmmap(void *, struct sbuf *, size_t *); 1549 1550 static int 1551 core_compressed_write(void *base, size_t len, off_t offset, void *arg) 1552 { 1553 1554 return (core_write((struct coredump_params *)arg, base, len, offset, 1555 UIO_SYSSPACE, NULL)); 1556 } 1557 1558 int 1559 __elfN(coredump)(struct thread *td, struct vnode *vp, off_t limit, int flags) 1560 { 1561 struct ucred *cred = td->td_ucred; 1562 int compm, error = 0; 1563 struct sseg_closure seginfo; 1564 struct note_info_list notelst; 1565 struct coredump_params params; 1566 struct note_info *ninfo; 1567 void *hdr, *tmpbuf; 1568 size_t hdrsize, notesz, coresize; 1569 1570 hdr = NULL; 1571 tmpbuf = NULL; 1572 TAILQ_INIT(¬elst); 1573 1574 /* Size the program segments. */ 1575 __elfN(size_segments)(td, &seginfo, flags); 1576 1577 /* 1578 * Collect info about the core file header area. 1579 */ 1580 hdrsize = sizeof(Elf_Ehdr) + sizeof(Elf_Phdr) * (1 + seginfo.count); 1581 if (seginfo.count + 1 >= PN_XNUM) 1582 hdrsize += sizeof(Elf_Shdr); 1583 td->td_proc->p_sysent->sv_elf_core_prepare_notes(td, ¬elst, ¬esz); 1584 coresize = round_page(hdrsize + notesz) + seginfo.size; 1585 1586 /* Set up core dump parameters. */ 1587 params.offset = 0; 1588 params.active_cred = cred; 1589 params.file_cred = NOCRED; 1590 params.td = td; 1591 params.vp = vp; 1592 params.comp = NULL; 1593 1594 #ifdef RACCT 1595 if (racct_enable) { 1596 PROC_LOCK(td->td_proc); 1597 error = racct_add(td->td_proc, RACCT_CORE, coresize); 1598 PROC_UNLOCK(td->td_proc); 1599 if (error != 0) { 1600 error = EFAULT; 1601 goto done; 1602 } 1603 } 1604 #endif 1605 if (coresize >= limit) { 1606 error = EFAULT; 1607 goto done; 1608 } 1609 1610 /* Create a compression stream if necessary. */ 1611 compm = compress_user_cores; 1612 if ((flags & (SVC_PT_COREDUMP | SVC_NOCOMPRESS)) == SVC_PT_COREDUMP && 1613 compm == 0) 1614 compm = COMPRESS_GZIP; 1615 if (compm != 0) { 1616 params.comp = compressor_init(core_compressed_write, 1617 compm, CORE_BUF_SIZE, 1618 compress_user_cores_level, ¶ms); 1619 if (params.comp == NULL) { 1620 error = EFAULT; 1621 goto done; 1622 } 1623 tmpbuf = malloc(CORE_BUF_SIZE, M_TEMP, M_WAITOK | M_ZERO); 1624 } 1625 1626 /* 1627 * Allocate memory for building the header, fill it up, 1628 * and write it out following the notes. 1629 */ 1630 hdr = malloc(hdrsize, M_TEMP, M_WAITOK); 1631 error = __elfN(corehdr)(¶ms, seginfo.count, hdr, hdrsize, ¬elst, 1632 notesz, flags); 1633 1634 /* Write the contents of all of the writable segments. */ 1635 if (error == 0) { 1636 Elf_Phdr *php; 1637 off_t offset; 1638 int i; 1639 1640 php = (Elf_Phdr *)((char *)hdr + sizeof(Elf_Ehdr)) + 1; 1641 offset = round_page(hdrsize + notesz); 1642 for (i = 0; i < seginfo.count; i++) { 1643 error = core_output((char *)(uintptr_t)php->p_vaddr, 1644 php->p_filesz, offset, ¶ms, tmpbuf); 1645 if (error != 0) 1646 break; 1647 offset += php->p_filesz; 1648 php++; 1649 } 1650 if (error == 0 && params.comp != NULL) 1651 error = compressor_flush(params.comp); 1652 } 1653 if (error) { 1654 log(LOG_WARNING, 1655 "Failed to write core file for process %s (error %d)\n", 1656 curproc->p_comm, error); 1657 } 1658 1659 done: 1660 free(tmpbuf, M_TEMP); 1661 if (params.comp != NULL) 1662 compressor_fini(params.comp); 1663 while ((ninfo = TAILQ_FIRST(¬elst)) != NULL) { 1664 TAILQ_REMOVE(¬elst, ninfo, link); 1665 free(ninfo, M_TEMP); 1666 } 1667 if (hdr != NULL) 1668 free(hdr, M_TEMP); 1669 1670 return (error); 1671 } 1672 1673 /* 1674 * A callback for each_dumpable_segment() to write out the segment's 1675 * program header entry. 1676 */ 1677 static void 1678 cb_put_phdr(vm_map_entry_t entry, void *closure) 1679 { 1680 struct phdr_closure *phc = (struct phdr_closure *)closure; 1681 Elf_Phdr *phdr = phc->phdr; 1682 1683 phc->offset = round_page(phc->offset); 1684 1685 phdr->p_type = PT_LOAD; 1686 phdr->p_offset = phc->offset; 1687 phdr->p_vaddr = entry->start; 1688 phdr->p_paddr = 0; 1689 phdr->p_filesz = phdr->p_memsz = entry->end - entry->start; 1690 phdr->p_align = PAGE_SIZE; 1691 phdr->p_flags = __elfN(untrans_prot)(entry->protection); 1692 1693 phc->offset += phdr->p_filesz; 1694 phc->phdr++; 1695 } 1696 1697 /* 1698 * A callback for each_dumpable_segment() to gather information about 1699 * the number of segments and their total size. 1700 */ 1701 static void 1702 cb_size_segment(vm_map_entry_t entry, void *closure) 1703 { 1704 struct sseg_closure *ssc = (struct sseg_closure *)closure; 1705 1706 ssc->count++; 1707 ssc->size += entry->end - entry->start; 1708 } 1709 1710 void 1711 __elfN(size_segments)(struct thread *td, struct sseg_closure *seginfo, 1712 int flags) 1713 { 1714 seginfo->count = 0; 1715 seginfo->size = 0; 1716 1717 each_dumpable_segment(td, cb_size_segment, seginfo, flags); 1718 } 1719 1720 /* 1721 * For each writable segment in the process's memory map, call the given 1722 * function with a pointer to the map entry and some arbitrary 1723 * caller-supplied data. 1724 */ 1725 static void 1726 each_dumpable_segment(struct thread *td, segment_callback func, void *closure, 1727 int flags) 1728 { 1729 struct proc *p = td->td_proc; 1730 vm_map_t map = &p->p_vmspace->vm_map; 1731 vm_map_entry_t entry; 1732 vm_object_t backing_object, object; 1733 bool ignore_entry; 1734 1735 vm_map_lock_read(map); 1736 VM_MAP_ENTRY_FOREACH(entry, map) { 1737 /* 1738 * Don't dump inaccessible mappings, deal with legacy 1739 * coredump mode. 1740 * 1741 * Note that read-only segments related to the elf binary 1742 * are marked MAP_ENTRY_NOCOREDUMP now so we no longer 1743 * need to arbitrarily ignore such segments. 1744 */ 1745 if ((flags & SVC_ALL) == 0) { 1746 if (elf_legacy_coredump) { 1747 if ((entry->protection & VM_PROT_RW) != 1748 VM_PROT_RW) 1749 continue; 1750 } else { 1751 if ((entry->protection & VM_PROT_ALL) == 0) 1752 continue; 1753 } 1754 } 1755 1756 /* 1757 * Dont include memory segment in the coredump if 1758 * MAP_NOCORE is set in mmap(2) or MADV_NOCORE in 1759 * madvise(2). Do not dump submaps (i.e. parts of the 1760 * kernel map). 1761 */ 1762 if ((entry->eflags & MAP_ENTRY_IS_SUB_MAP) != 0) 1763 continue; 1764 if ((entry->eflags & MAP_ENTRY_NOCOREDUMP) != 0 && 1765 (flags & SVC_ALL) == 0) 1766 continue; 1767 if ((object = entry->object.vm_object) == NULL) 1768 continue; 1769 1770 /* Ignore memory-mapped devices and such things. */ 1771 VM_OBJECT_RLOCK(object); 1772 while ((backing_object = object->backing_object) != NULL) { 1773 VM_OBJECT_RLOCK(backing_object); 1774 VM_OBJECT_RUNLOCK(object); 1775 object = backing_object; 1776 } 1777 ignore_entry = (object->flags & OBJ_FICTITIOUS) != 0; 1778 VM_OBJECT_RUNLOCK(object); 1779 if (ignore_entry) 1780 continue; 1781 1782 (*func)(entry, closure); 1783 } 1784 vm_map_unlock_read(map); 1785 } 1786 1787 /* 1788 * Write the core file header to the file, including padding up to 1789 * the page boundary. 1790 */ 1791 static int 1792 __elfN(corehdr)(struct coredump_params *p, int numsegs, void *hdr, 1793 size_t hdrsize, struct note_info_list *notelst, size_t notesz, 1794 int flags) 1795 { 1796 struct note_info *ninfo; 1797 struct sbuf *sb; 1798 int error; 1799 1800 /* Fill in the header. */ 1801 bzero(hdr, hdrsize); 1802 __elfN(puthdr)(p->td, hdr, hdrsize, numsegs, notesz, flags); 1803 1804 sb = sbuf_new(NULL, NULL, CORE_BUF_SIZE, SBUF_FIXEDLEN); 1805 sbuf_set_drain(sb, sbuf_drain_core_output, p); 1806 sbuf_start_section(sb, NULL); 1807 sbuf_bcat(sb, hdr, hdrsize); 1808 TAILQ_FOREACH(ninfo, notelst, link) 1809 __elfN(putnote)(p->td, ninfo, sb); 1810 /* Align up to a page boundary for the program segments. */ 1811 sbuf_end_section(sb, -1, PAGE_SIZE, 0); 1812 error = sbuf_finish(sb); 1813 sbuf_delete(sb); 1814 1815 return (error); 1816 } 1817 1818 void 1819 __elfN(prepare_notes)(struct thread *td, struct note_info_list *list, 1820 size_t *sizep) 1821 { 1822 struct proc *p; 1823 struct thread *thr; 1824 size_t size; 1825 1826 p = td->td_proc; 1827 size = 0; 1828 1829 size += __elfN(register_note)(td, list, NT_PRPSINFO, __elfN(note_prpsinfo), p); 1830 1831 /* 1832 * To have the debugger select the right thread (LWP) as the initial 1833 * thread, we dump the state of the thread passed to us in td first. 1834 * This is the thread that causes the core dump and thus likely to 1835 * be the right thread one wants to have selected in the debugger. 1836 */ 1837 thr = td; 1838 while (thr != NULL) { 1839 size += __elfN(register_note)(td, list, NT_PRSTATUS, 1840 __elfN(note_prstatus), thr); 1841 size += __elfN(register_note)(td, list, NT_FPREGSET, 1842 __elfN(note_fpregset), thr); 1843 size += __elfN(register_note)(td, list, NT_THRMISC, 1844 __elfN(note_thrmisc), thr); 1845 size += __elfN(register_note)(td, list, NT_PTLWPINFO, 1846 __elfN(note_ptlwpinfo), thr); 1847 size += __elfN(register_note)(td, list, -1, 1848 __elfN(note_threadmd), thr); 1849 1850 thr = thr == td ? TAILQ_FIRST(&p->p_threads) : 1851 TAILQ_NEXT(thr, td_plist); 1852 if (thr == td) 1853 thr = TAILQ_NEXT(thr, td_plist); 1854 } 1855 1856 size += __elfN(register_note)(td, list, NT_PROCSTAT_PROC, 1857 __elfN(note_procstat_proc), p); 1858 size += __elfN(register_note)(td, list, NT_PROCSTAT_FILES, 1859 note_procstat_files, p); 1860 size += __elfN(register_note)(td, list, NT_PROCSTAT_VMMAP, 1861 note_procstat_vmmap, p); 1862 size += __elfN(register_note)(td, list, NT_PROCSTAT_GROUPS, 1863 note_procstat_groups, p); 1864 size += __elfN(register_note)(td, list, NT_PROCSTAT_UMASK, 1865 note_procstat_umask, p); 1866 size += __elfN(register_note)(td, list, NT_PROCSTAT_RLIMIT, 1867 note_procstat_rlimit, p); 1868 size += __elfN(register_note)(td, list, NT_PROCSTAT_OSREL, 1869 note_procstat_osrel, p); 1870 size += __elfN(register_note)(td, list, NT_PROCSTAT_PSSTRINGS, 1871 __elfN(note_procstat_psstrings), p); 1872 size += __elfN(register_note)(td, list, NT_PROCSTAT_AUXV, 1873 __elfN(note_procstat_auxv), p); 1874 1875 *sizep = size; 1876 } 1877 1878 void 1879 __elfN(puthdr)(struct thread *td, void *hdr, size_t hdrsize, int numsegs, 1880 size_t notesz, int flags) 1881 { 1882 Elf_Ehdr *ehdr; 1883 Elf_Phdr *phdr; 1884 Elf_Shdr *shdr; 1885 struct phdr_closure phc; 1886 Elf_Brandinfo *bi; 1887 1888 ehdr = (Elf_Ehdr *)hdr; 1889 bi = td->td_proc->p_elf_brandinfo; 1890 1891 ehdr->e_ident[EI_MAG0] = ELFMAG0; 1892 ehdr->e_ident[EI_MAG1] = ELFMAG1; 1893 ehdr->e_ident[EI_MAG2] = ELFMAG2; 1894 ehdr->e_ident[EI_MAG3] = ELFMAG3; 1895 ehdr->e_ident[EI_CLASS] = ELF_CLASS; 1896 ehdr->e_ident[EI_DATA] = ELF_DATA; 1897 ehdr->e_ident[EI_VERSION] = EV_CURRENT; 1898 ehdr->e_ident[EI_OSABI] = td->td_proc->p_sysent->sv_elf_core_osabi; 1899 ehdr->e_ident[EI_ABIVERSION] = 0; 1900 ehdr->e_ident[EI_PAD] = 0; 1901 ehdr->e_type = ET_CORE; 1902 ehdr->e_machine = bi->machine; 1903 ehdr->e_version = EV_CURRENT; 1904 ehdr->e_entry = 0; 1905 ehdr->e_phoff = sizeof(Elf_Ehdr); 1906 ehdr->e_flags = td->td_proc->p_elf_flags; 1907 ehdr->e_ehsize = sizeof(Elf_Ehdr); 1908 ehdr->e_phentsize = sizeof(Elf_Phdr); 1909 ehdr->e_shentsize = sizeof(Elf_Shdr); 1910 ehdr->e_shstrndx = SHN_UNDEF; 1911 if (numsegs + 1 < PN_XNUM) { 1912 ehdr->e_phnum = numsegs + 1; 1913 ehdr->e_shnum = 0; 1914 } else { 1915 ehdr->e_phnum = PN_XNUM; 1916 ehdr->e_shnum = 1; 1917 1918 ehdr->e_shoff = ehdr->e_phoff + 1919 (numsegs + 1) * ehdr->e_phentsize; 1920 KASSERT(ehdr->e_shoff == hdrsize - sizeof(Elf_Shdr), 1921 ("e_shoff: %zu, hdrsize - shdr: %zu", 1922 (size_t)ehdr->e_shoff, hdrsize - sizeof(Elf_Shdr))); 1923 1924 shdr = (Elf_Shdr *)((char *)hdr + ehdr->e_shoff); 1925 memset(shdr, 0, sizeof(*shdr)); 1926 /* 1927 * A special first section is used to hold large segment and 1928 * section counts. This was proposed by Sun Microsystems in 1929 * Solaris and has been adopted by Linux; the standard ELF 1930 * tools are already familiar with the technique. 1931 * 1932 * See table 7-7 of the Solaris "Linker and Libraries Guide" 1933 * (or 12-7 depending on the version of the document) for more 1934 * details. 1935 */ 1936 shdr->sh_type = SHT_NULL; 1937 shdr->sh_size = ehdr->e_shnum; 1938 shdr->sh_link = ehdr->e_shstrndx; 1939 shdr->sh_info = numsegs + 1; 1940 } 1941 1942 /* 1943 * Fill in the program header entries. 1944 */ 1945 phdr = (Elf_Phdr *)((char *)hdr + ehdr->e_phoff); 1946 1947 /* The note segement. */ 1948 phdr->p_type = PT_NOTE; 1949 phdr->p_offset = hdrsize; 1950 phdr->p_vaddr = 0; 1951 phdr->p_paddr = 0; 1952 phdr->p_filesz = notesz; 1953 phdr->p_memsz = 0; 1954 phdr->p_flags = PF_R; 1955 phdr->p_align = ELF_NOTE_ROUNDSIZE; 1956 phdr++; 1957 1958 /* All the writable segments from the program. */ 1959 phc.phdr = phdr; 1960 phc.offset = round_page(hdrsize + notesz); 1961 each_dumpable_segment(td, cb_put_phdr, &phc, flags); 1962 } 1963 1964 size_t 1965 __elfN(register_note)(struct thread *td, struct note_info_list *list, 1966 int type, outfunc_t out, void *arg) 1967 { 1968 const struct sysentvec *sv; 1969 struct note_info *ninfo; 1970 size_t size, notesize; 1971 1972 sv = td->td_proc->p_sysent; 1973 size = 0; 1974 out(arg, NULL, &size); 1975 ninfo = malloc(sizeof(*ninfo), M_TEMP, M_ZERO | M_WAITOK); 1976 ninfo->type = type; 1977 ninfo->outfunc = out; 1978 ninfo->outarg = arg; 1979 ninfo->outsize = size; 1980 TAILQ_INSERT_TAIL(list, ninfo, link); 1981 1982 if (type == -1) 1983 return (size); 1984 1985 notesize = sizeof(Elf_Note) + /* note header */ 1986 roundup2(strlen(sv->sv_elf_core_abi_vendor) + 1, ELF_NOTE_ROUNDSIZE) + 1987 /* note name */ 1988 roundup2(size, ELF_NOTE_ROUNDSIZE); /* note description */ 1989 1990 return (notesize); 1991 } 1992 1993 static size_t 1994 append_note_data(const void *src, void *dst, size_t len) 1995 { 1996 size_t padded_len; 1997 1998 padded_len = roundup2(len, ELF_NOTE_ROUNDSIZE); 1999 if (dst != NULL) { 2000 bcopy(src, dst, len); 2001 bzero((char *)dst + len, padded_len - len); 2002 } 2003 return (padded_len); 2004 } 2005 2006 size_t 2007 __elfN(populate_note)(int type, void *src, void *dst, size_t size, void **descp) 2008 { 2009 Elf_Note *note; 2010 char *buf; 2011 size_t notesize; 2012 2013 buf = dst; 2014 if (buf != NULL) { 2015 note = (Elf_Note *)buf; 2016 note->n_namesz = sizeof(FREEBSD_ABI_VENDOR); 2017 note->n_descsz = size; 2018 note->n_type = type; 2019 buf += sizeof(*note); 2020 buf += append_note_data(FREEBSD_ABI_VENDOR, buf, 2021 sizeof(FREEBSD_ABI_VENDOR)); 2022 append_note_data(src, buf, size); 2023 if (descp != NULL) 2024 *descp = buf; 2025 } 2026 2027 notesize = sizeof(Elf_Note) + /* note header */ 2028 roundup2(sizeof(FREEBSD_ABI_VENDOR), ELF_NOTE_ROUNDSIZE) + 2029 /* note name */ 2030 roundup2(size, ELF_NOTE_ROUNDSIZE); /* note description */ 2031 2032 return (notesize); 2033 } 2034 2035 static void 2036 __elfN(putnote)(struct thread *td, struct note_info *ninfo, struct sbuf *sb) 2037 { 2038 Elf_Note note; 2039 const struct sysentvec *sv; 2040 ssize_t old_len, sect_len; 2041 size_t new_len, descsz, i; 2042 2043 if (ninfo->type == -1) { 2044 ninfo->outfunc(ninfo->outarg, sb, &ninfo->outsize); 2045 return; 2046 } 2047 2048 sv = td->td_proc->p_sysent; 2049 2050 note.n_namesz = strlen(sv->sv_elf_core_abi_vendor) + 1; 2051 note.n_descsz = ninfo->outsize; 2052 note.n_type = ninfo->type; 2053 2054 sbuf_bcat(sb, ¬e, sizeof(note)); 2055 sbuf_start_section(sb, &old_len); 2056 sbuf_bcat(sb, sv->sv_elf_core_abi_vendor, 2057 strlen(sv->sv_elf_core_abi_vendor) + 1); 2058 sbuf_end_section(sb, old_len, ELF_NOTE_ROUNDSIZE, 0); 2059 if (note.n_descsz == 0) 2060 return; 2061 sbuf_start_section(sb, &old_len); 2062 ninfo->outfunc(ninfo->outarg, sb, &ninfo->outsize); 2063 sect_len = sbuf_end_section(sb, old_len, ELF_NOTE_ROUNDSIZE, 0); 2064 if (sect_len < 0) 2065 return; 2066 2067 new_len = (size_t)sect_len; 2068 descsz = roundup(note.n_descsz, ELF_NOTE_ROUNDSIZE); 2069 if (new_len < descsz) { 2070 /* 2071 * It is expected that individual note emitters will correctly 2072 * predict their expected output size and fill up to that size 2073 * themselves, padding in a format-specific way if needed. 2074 * However, in case they don't, just do it here with zeros. 2075 */ 2076 for (i = 0; i < descsz - new_len; i++) 2077 sbuf_putc(sb, 0); 2078 } else if (new_len > descsz) { 2079 /* 2080 * We can't always truncate sb -- we may have drained some 2081 * of it already. 2082 */ 2083 KASSERT(new_len == descsz, ("%s: Note type %u changed as we " 2084 "read it (%zu > %zu). Since it is longer than " 2085 "expected, this coredump's notes are corrupt. THIS " 2086 "IS A BUG in the note_procstat routine for type %u.\n", 2087 __func__, (unsigned)note.n_type, new_len, descsz, 2088 (unsigned)note.n_type)); 2089 } 2090 } 2091 2092 /* 2093 * Miscellaneous note out functions. 2094 */ 2095 2096 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32 2097 #include <compat/freebsd32/freebsd32.h> 2098 #include <compat/freebsd32/freebsd32_signal.h> 2099 2100 typedef struct prstatus32 elf_prstatus_t; 2101 typedef struct prpsinfo32 elf_prpsinfo_t; 2102 typedef struct fpreg32 elf_prfpregset_t; 2103 typedef struct fpreg32 elf_fpregset_t; 2104 typedef struct reg32 elf_gregset_t; 2105 typedef struct thrmisc32 elf_thrmisc_t; 2106 #define ELF_KERN_PROC_MASK KERN_PROC_MASK32 2107 typedef struct kinfo_proc32 elf_kinfo_proc_t; 2108 typedef uint32_t elf_ps_strings_t; 2109 #else 2110 typedef prstatus_t elf_prstatus_t; 2111 typedef prpsinfo_t elf_prpsinfo_t; 2112 typedef prfpregset_t elf_prfpregset_t; 2113 typedef prfpregset_t elf_fpregset_t; 2114 typedef gregset_t elf_gregset_t; 2115 typedef thrmisc_t elf_thrmisc_t; 2116 #define ELF_KERN_PROC_MASK 0 2117 typedef struct kinfo_proc elf_kinfo_proc_t; 2118 typedef vm_offset_t elf_ps_strings_t; 2119 #endif 2120 2121 static void 2122 __elfN(note_prpsinfo)(void *arg, struct sbuf *sb, size_t *sizep) 2123 { 2124 struct sbuf sbarg; 2125 size_t len; 2126 char *cp, *end; 2127 struct proc *p; 2128 elf_prpsinfo_t *psinfo; 2129 int error; 2130 2131 p = arg; 2132 if (sb != NULL) { 2133 KASSERT(*sizep == sizeof(*psinfo), ("invalid size")); 2134 psinfo = malloc(sizeof(*psinfo), M_TEMP, M_ZERO | M_WAITOK); 2135 psinfo->pr_version = PRPSINFO_VERSION; 2136 psinfo->pr_psinfosz = sizeof(elf_prpsinfo_t); 2137 strlcpy(psinfo->pr_fname, p->p_comm, sizeof(psinfo->pr_fname)); 2138 PROC_LOCK(p); 2139 if (p->p_args != NULL) { 2140 len = sizeof(psinfo->pr_psargs) - 1; 2141 if (len > p->p_args->ar_length) 2142 len = p->p_args->ar_length; 2143 memcpy(psinfo->pr_psargs, p->p_args->ar_args, len); 2144 PROC_UNLOCK(p); 2145 error = 0; 2146 } else { 2147 _PHOLD(p); 2148 PROC_UNLOCK(p); 2149 sbuf_new(&sbarg, psinfo->pr_psargs, 2150 sizeof(psinfo->pr_psargs), SBUF_FIXEDLEN); 2151 error = proc_getargv(curthread, p, &sbarg); 2152 PRELE(p); 2153 if (sbuf_finish(&sbarg) == 0) 2154 len = sbuf_len(&sbarg) - 1; 2155 else 2156 len = sizeof(psinfo->pr_psargs) - 1; 2157 sbuf_delete(&sbarg); 2158 } 2159 if (error || len == 0) 2160 strlcpy(psinfo->pr_psargs, p->p_comm, 2161 sizeof(psinfo->pr_psargs)); 2162 else { 2163 KASSERT(len < sizeof(psinfo->pr_psargs), 2164 ("len is too long: %zu vs %zu", len, 2165 sizeof(psinfo->pr_psargs))); 2166 cp = psinfo->pr_psargs; 2167 end = cp + len - 1; 2168 for (;;) { 2169 cp = memchr(cp, '\0', end - cp); 2170 if (cp == NULL) 2171 break; 2172 *cp = ' '; 2173 } 2174 } 2175 psinfo->pr_pid = p->p_pid; 2176 sbuf_bcat(sb, psinfo, sizeof(*psinfo)); 2177 free(psinfo, M_TEMP); 2178 } 2179 *sizep = sizeof(*psinfo); 2180 } 2181 2182 static void 2183 __elfN(note_prstatus)(void *arg, struct sbuf *sb, size_t *sizep) 2184 { 2185 struct thread *td; 2186 elf_prstatus_t *status; 2187 2188 td = arg; 2189 if (sb != NULL) { 2190 KASSERT(*sizep == sizeof(*status), ("invalid size")); 2191 status = malloc(sizeof(*status), M_TEMP, M_ZERO | M_WAITOK); 2192 status->pr_version = PRSTATUS_VERSION; 2193 status->pr_statussz = sizeof(elf_prstatus_t); 2194 status->pr_gregsetsz = sizeof(elf_gregset_t); 2195 status->pr_fpregsetsz = sizeof(elf_fpregset_t); 2196 status->pr_osreldate = osreldate; 2197 status->pr_cursig = td->td_proc->p_sig; 2198 status->pr_pid = td->td_tid; 2199 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32 2200 fill_regs32(td, &status->pr_reg); 2201 #else 2202 fill_regs(td, &status->pr_reg); 2203 #endif 2204 sbuf_bcat(sb, status, sizeof(*status)); 2205 free(status, M_TEMP); 2206 } 2207 *sizep = sizeof(*status); 2208 } 2209 2210 static void 2211 __elfN(note_fpregset)(void *arg, struct sbuf *sb, size_t *sizep) 2212 { 2213 struct thread *td; 2214 elf_prfpregset_t *fpregset; 2215 2216 td = arg; 2217 if (sb != NULL) { 2218 KASSERT(*sizep == sizeof(*fpregset), ("invalid size")); 2219 fpregset = malloc(sizeof(*fpregset), M_TEMP, M_ZERO | M_WAITOK); 2220 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32 2221 fill_fpregs32(td, fpregset); 2222 #else 2223 fill_fpregs(td, fpregset); 2224 #endif 2225 sbuf_bcat(sb, fpregset, sizeof(*fpregset)); 2226 free(fpregset, M_TEMP); 2227 } 2228 *sizep = sizeof(*fpregset); 2229 } 2230 2231 static void 2232 __elfN(note_thrmisc)(void *arg, struct sbuf *sb, size_t *sizep) 2233 { 2234 struct thread *td; 2235 elf_thrmisc_t thrmisc; 2236 2237 td = arg; 2238 if (sb != NULL) { 2239 KASSERT(*sizep == sizeof(thrmisc), ("invalid size")); 2240 bzero(&thrmisc, sizeof(thrmisc)); 2241 strcpy(thrmisc.pr_tname, td->td_name); 2242 sbuf_bcat(sb, &thrmisc, sizeof(thrmisc)); 2243 } 2244 *sizep = sizeof(thrmisc); 2245 } 2246 2247 static void 2248 __elfN(note_ptlwpinfo)(void *arg, struct sbuf *sb, size_t *sizep) 2249 { 2250 struct thread *td; 2251 size_t size; 2252 int structsize; 2253 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32 2254 struct ptrace_lwpinfo32 pl; 2255 #else 2256 struct ptrace_lwpinfo pl; 2257 #endif 2258 2259 td = arg; 2260 size = sizeof(structsize) + sizeof(pl); 2261 if (sb != NULL) { 2262 KASSERT(*sizep == size, ("invalid size")); 2263 structsize = sizeof(pl); 2264 sbuf_bcat(sb, &structsize, sizeof(structsize)); 2265 bzero(&pl, sizeof(pl)); 2266 pl.pl_lwpid = td->td_tid; 2267 pl.pl_event = PL_EVENT_NONE; 2268 pl.pl_sigmask = td->td_sigmask; 2269 pl.pl_siglist = td->td_siglist; 2270 if (td->td_si.si_signo != 0) { 2271 pl.pl_event = PL_EVENT_SIGNAL; 2272 pl.pl_flags |= PL_FLAG_SI; 2273 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32 2274 siginfo_to_siginfo32(&td->td_si, &pl.pl_siginfo); 2275 #else 2276 pl.pl_siginfo = td->td_si; 2277 #endif 2278 } 2279 strcpy(pl.pl_tdname, td->td_name); 2280 /* XXX TODO: supply more information in struct ptrace_lwpinfo*/ 2281 sbuf_bcat(sb, &pl, sizeof(pl)); 2282 } 2283 *sizep = size; 2284 } 2285 2286 /* 2287 * Allow for MD specific notes, as well as any MD 2288 * specific preparations for writing MI notes. 2289 */ 2290 static void 2291 __elfN(note_threadmd)(void *arg, struct sbuf *sb, size_t *sizep) 2292 { 2293 struct thread *td; 2294 void *buf; 2295 size_t size; 2296 2297 td = (struct thread *)arg; 2298 size = *sizep; 2299 if (size != 0 && sb != NULL) 2300 buf = malloc(size, M_TEMP, M_ZERO | M_WAITOK); 2301 else 2302 buf = NULL; 2303 size = 0; 2304 __elfN(dump_thread)(td, buf, &size); 2305 KASSERT(sb == NULL || *sizep == size, ("invalid size")); 2306 if (size != 0 && sb != NULL) 2307 sbuf_bcat(sb, buf, size); 2308 free(buf, M_TEMP); 2309 *sizep = size; 2310 } 2311 2312 #ifdef KINFO_PROC_SIZE 2313 CTASSERT(sizeof(struct kinfo_proc) == KINFO_PROC_SIZE); 2314 #endif 2315 2316 static void 2317 __elfN(note_procstat_proc)(void *arg, struct sbuf *sb, size_t *sizep) 2318 { 2319 struct proc *p; 2320 size_t size; 2321 int structsize; 2322 2323 p = arg; 2324 size = sizeof(structsize) + p->p_numthreads * 2325 sizeof(elf_kinfo_proc_t); 2326 2327 if (sb != NULL) { 2328 KASSERT(*sizep == size, ("invalid size")); 2329 structsize = sizeof(elf_kinfo_proc_t); 2330 sbuf_bcat(sb, &structsize, sizeof(structsize)); 2331 sx_slock(&proctree_lock); 2332 PROC_LOCK(p); 2333 kern_proc_out(p, sb, ELF_KERN_PROC_MASK); 2334 sx_sunlock(&proctree_lock); 2335 } 2336 *sizep = size; 2337 } 2338 2339 #ifdef KINFO_FILE_SIZE 2340 CTASSERT(sizeof(struct kinfo_file) == KINFO_FILE_SIZE); 2341 #endif 2342 2343 static void 2344 note_procstat_files(void *arg, struct sbuf *sb, size_t *sizep) 2345 { 2346 struct proc *p; 2347 size_t size, sect_sz, i; 2348 ssize_t start_len, sect_len; 2349 int structsize, filedesc_flags; 2350 2351 if (coredump_pack_fileinfo) 2352 filedesc_flags = KERN_FILEDESC_PACK_KINFO; 2353 else 2354 filedesc_flags = 0; 2355 2356 p = arg; 2357 structsize = sizeof(struct kinfo_file); 2358 if (sb == NULL) { 2359 size = 0; 2360 sb = sbuf_new(NULL, NULL, 128, SBUF_FIXEDLEN); 2361 sbuf_set_drain(sb, sbuf_count_drain, &size); 2362 sbuf_bcat(sb, &structsize, sizeof(structsize)); 2363 PROC_LOCK(p); 2364 kern_proc_filedesc_out(p, sb, -1, filedesc_flags); 2365 sbuf_finish(sb); 2366 sbuf_delete(sb); 2367 *sizep = size; 2368 } else { 2369 sbuf_start_section(sb, &start_len); 2370 2371 sbuf_bcat(sb, &structsize, sizeof(structsize)); 2372 PROC_LOCK(p); 2373 kern_proc_filedesc_out(p, sb, *sizep - sizeof(structsize), 2374 filedesc_flags); 2375 2376 sect_len = sbuf_end_section(sb, start_len, 0, 0); 2377 if (sect_len < 0) 2378 return; 2379 sect_sz = sect_len; 2380 2381 KASSERT(sect_sz <= *sizep, 2382 ("kern_proc_filedesc_out did not respect maxlen; " 2383 "requested %zu, got %zu", *sizep - sizeof(structsize), 2384 sect_sz - sizeof(structsize))); 2385 2386 for (i = 0; i < *sizep - sect_sz && sb->s_error == 0; i++) 2387 sbuf_putc(sb, 0); 2388 } 2389 } 2390 2391 #ifdef KINFO_VMENTRY_SIZE 2392 CTASSERT(sizeof(struct kinfo_vmentry) == KINFO_VMENTRY_SIZE); 2393 #endif 2394 2395 static void 2396 note_procstat_vmmap(void *arg, struct sbuf *sb, size_t *sizep) 2397 { 2398 struct proc *p; 2399 size_t size; 2400 int structsize, vmmap_flags; 2401 2402 if (coredump_pack_vmmapinfo) 2403 vmmap_flags = KERN_VMMAP_PACK_KINFO; 2404 else 2405 vmmap_flags = 0; 2406 2407 p = arg; 2408 structsize = sizeof(struct kinfo_vmentry); 2409 if (sb == NULL) { 2410 size = 0; 2411 sb = sbuf_new(NULL, NULL, 128, SBUF_FIXEDLEN); 2412 sbuf_set_drain(sb, sbuf_count_drain, &size); 2413 sbuf_bcat(sb, &structsize, sizeof(structsize)); 2414 PROC_LOCK(p); 2415 kern_proc_vmmap_out(p, sb, -1, vmmap_flags); 2416 sbuf_finish(sb); 2417 sbuf_delete(sb); 2418 *sizep = size; 2419 } else { 2420 sbuf_bcat(sb, &structsize, sizeof(structsize)); 2421 PROC_LOCK(p); 2422 kern_proc_vmmap_out(p, sb, *sizep - sizeof(structsize), 2423 vmmap_flags); 2424 } 2425 } 2426 2427 static void 2428 note_procstat_groups(void *arg, struct sbuf *sb, size_t *sizep) 2429 { 2430 struct proc *p; 2431 size_t size; 2432 int structsize; 2433 2434 p = arg; 2435 size = sizeof(structsize) + p->p_ucred->cr_ngroups * sizeof(gid_t); 2436 if (sb != NULL) { 2437 KASSERT(*sizep == size, ("invalid size")); 2438 structsize = sizeof(gid_t); 2439 sbuf_bcat(sb, &structsize, sizeof(structsize)); 2440 sbuf_bcat(sb, p->p_ucred->cr_groups, p->p_ucred->cr_ngroups * 2441 sizeof(gid_t)); 2442 } 2443 *sizep = size; 2444 } 2445 2446 static void 2447 note_procstat_umask(void *arg, struct sbuf *sb, size_t *sizep) 2448 { 2449 struct proc *p; 2450 size_t size; 2451 int structsize; 2452 2453 p = arg; 2454 size = sizeof(structsize) + sizeof(p->p_pd->pd_cmask); 2455 if (sb != NULL) { 2456 KASSERT(*sizep == size, ("invalid size")); 2457 structsize = sizeof(p->p_pd->pd_cmask); 2458 sbuf_bcat(sb, &structsize, sizeof(structsize)); 2459 sbuf_bcat(sb, &p->p_pd->pd_cmask, sizeof(p->p_pd->pd_cmask)); 2460 } 2461 *sizep = size; 2462 } 2463 2464 static void 2465 note_procstat_rlimit(void *arg, struct sbuf *sb, size_t *sizep) 2466 { 2467 struct proc *p; 2468 struct rlimit rlim[RLIM_NLIMITS]; 2469 size_t size; 2470 int structsize, i; 2471 2472 p = arg; 2473 size = sizeof(structsize) + sizeof(rlim); 2474 if (sb != NULL) { 2475 KASSERT(*sizep == size, ("invalid size")); 2476 structsize = sizeof(rlim); 2477 sbuf_bcat(sb, &structsize, sizeof(structsize)); 2478 PROC_LOCK(p); 2479 for (i = 0; i < RLIM_NLIMITS; i++) 2480 lim_rlimit_proc(p, i, &rlim[i]); 2481 PROC_UNLOCK(p); 2482 sbuf_bcat(sb, rlim, sizeof(rlim)); 2483 } 2484 *sizep = size; 2485 } 2486 2487 static void 2488 note_procstat_osrel(void *arg, struct sbuf *sb, size_t *sizep) 2489 { 2490 struct proc *p; 2491 size_t size; 2492 int structsize; 2493 2494 p = arg; 2495 size = sizeof(structsize) + sizeof(p->p_osrel); 2496 if (sb != NULL) { 2497 KASSERT(*sizep == size, ("invalid size")); 2498 structsize = sizeof(p->p_osrel); 2499 sbuf_bcat(sb, &structsize, sizeof(structsize)); 2500 sbuf_bcat(sb, &p->p_osrel, sizeof(p->p_osrel)); 2501 } 2502 *sizep = size; 2503 } 2504 2505 static void 2506 __elfN(note_procstat_psstrings)(void *arg, struct sbuf *sb, size_t *sizep) 2507 { 2508 struct proc *p; 2509 elf_ps_strings_t ps_strings; 2510 size_t size; 2511 int structsize; 2512 2513 p = arg; 2514 size = sizeof(structsize) + sizeof(ps_strings); 2515 if (sb != NULL) { 2516 KASSERT(*sizep == size, ("invalid size")); 2517 structsize = sizeof(ps_strings); 2518 #if defined(COMPAT_FREEBSD32) && __ELF_WORD_SIZE == 32 2519 ps_strings = PTROUT(p->p_sysent->sv_psstrings); 2520 #else 2521 ps_strings = p->p_sysent->sv_psstrings; 2522 #endif 2523 sbuf_bcat(sb, &structsize, sizeof(structsize)); 2524 sbuf_bcat(sb, &ps_strings, sizeof(ps_strings)); 2525 } 2526 *sizep = size; 2527 } 2528 2529 static void 2530 __elfN(note_procstat_auxv)(void *arg, struct sbuf *sb, size_t *sizep) 2531 { 2532 struct proc *p; 2533 size_t size; 2534 int structsize; 2535 2536 p = arg; 2537 if (sb == NULL) { 2538 size = 0; 2539 sb = sbuf_new(NULL, NULL, AT_COUNT * sizeof(Elf_Auxinfo), 2540 SBUF_FIXEDLEN); 2541 sbuf_set_drain(sb, sbuf_count_drain, &size); 2542 sbuf_bcat(sb, &structsize, sizeof(structsize)); 2543 PHOLD(p); 2544 proc_getauxv(curthread, p, sb); 2545 PRELE(p); 2546 sbuf_finish(sb); 2547 sbuf_delete(sb); 2548 *sizep = size; 2549 } else { 2550 structsize = sizeof(Elf_Auxinfo); 2551 sbuf_bcat(sb, &structsize, sizeof(structsize)); 2552 PHOLD(p); 2553 proc_getauxv(curthread, p, sb); 2554 PRELE(p); 2555 } 2556 } 2557 2558 static bool 2559 __elfN(parse_notes)(struct image_params *imgp, Elf_Note *checknote, 2560 const char *note_vendor, const Elf_Phdr *pnote, 2561 bool (*cb)(const Elf_Note *, void *, bool *), void *cb_arg) 2562 { 2563 const Elf_Note *note, *note0, *note_end; 2564 const char *note_name; 2565 char *buf; 2566 int i, error; 2567 bool res; 2568 2569 /* We need some limit, might as well use PAGE_SIZE. */ 2570 if (pnote == NULL || pnote->p_filesz > PAGE_SIZE) 2571 return (false); 2572 ASSERT_VOP_LOCKED(imgp->vp, "parse_notes"); 2573 if (pnote->p_offset > PAGE_SIZE || 2574 pnote->p_filesz > PAGE_SIZE - pnote->p_offset) { 2575 buf = malloc(pnote->p_filesz, M_TEMP, M_NOWAIT); 2576 if (buf == NULL) { 2577 VOP_UNLOCK(imgp->vp); 2578 buf = malloc(pnote->p_filesz, M_TEMP, M_WAITOK); 2579 vn_lock(imgp->vp, LK_SHARED | LK_RETRY); 2580 } 2581 error = vn_rdwr(UIO_READ, imgp->vp, buf, pnote->p_filesz, 2582 pnote->p_offset, UIO_SYSSPACE, IO_NODELOCKED, 2583 curthread->td_ucred, NOCRED, NULL, curthread); 2584 if (error != 0) { 2585 uprintf("i/o error PT_NOTE\n"); 2586 goto retf; 2587 } 2588 note = note0 = (const Elf_Note *)buf; 2589 note_end = (const Elf_Note *)(buf + pnote->p_filesz); 2590 } else { 2591 note = note0 = (const Elf_Note *)(imgp->image_header + 2592 pnote->p_offset); 2593 note_end = (const Elf_Note *)(imgp->image_header + 2594 pnote->p_offset + pnote->p_filesz); 2595 buf = NULL; 2596 } 2597 for (i = 0; i < 100 && note >= note0 && note < note_end; i++) { 2598 if (!aligned(note, Elf32_Addr) || (const char *)note_end - 2599 (const char *)note < sizeof(Elf_Note)) { 2600 goto retf; 2601 } 2602 if (note->n_namesz != checknote->n_namesz || 2603 note->n_descsz != checknote->n_descsz || 2604 note->n_type != checknote->n_type) 2605 goto nextnote; 2606 note_name = (const char *)(note + 1); 2607 if (note_name + checknote->n_namesz >= 2608 (const char *)note_end || strncmp(note_vendor, 2609 note_name, checknote->n_namesz) != 0) 2610 goto nextnote; 2611 2612 if (cb(note, cb_arg, &res)) 2613 goto ret; 2614 nextnote: 2615 note = (const Elf_Note *)((const char *)(note + 1) + 2616 roundup2(note->n_namesz, ELF_NOTE_ROUNDSIZE) + 2617 roundup2(note->n_descsz, ELF_NOTE_ROUNDSIZE)); 2618 } 2619 retf: 2620 res = false; 2621 ret: 2622 free(buf, M_TEMP); 2623 return (res); 2624 } 2625 2626 struct brandnote_cb_arg { 2627 Elf_Brandnote *brandnote; 2628 int32_t *osrel; 2629 }; 2630 2631 static bool 2632 brandnote_cb(const Elf_Note *note, void *arg0, bool *res) 2633 { 2634 struct brandnote_cb_arg *arg; 2635 2636 arg = arg0; 2637 2638 /* 2639 * Fetch the osreldate for binary from the ELF OSABI-note if 2640 * necessary. 2641 */ 2642 *res = (arg->brandnote->flags & BN_TRANSLATE_OSREL) != 0 && 2643 arg->brandnote->trans_osrel != NULL ? 2644 arg->brandnote->trans_osrel(note, arg->osrel) : true; 2645 2646 return (true); 2647 } 2648 2649 static Elf_Note fctl_note = { 2650 .n_namesz = sizeof(FREEBSD_ABI_VENDOR), 2651 .n_descsz = sizeof(uint32_t), 2652 .n_type = NT_FREEBSD_FEATURE_CTL, 2653 }; 2654 2655 struct fctl_cb_arg { 2656 bool *has_fctl0; 2657 uint32_t *fctl0; 2658 }; 2659 2660 static bool 2661 note_fctl_cb(const Elf_Note *note, void *arg0, bool *res) 2662 { 2663 struct fctl_cb_arg *arg; 2664 const Elf32_Word *desc; 2665 uintptr_t p; 2666 2667 arg = arg0; 2668 p = (uintptr_t)(note + 1); 2669 p += roundup2(note->n_namesz, ELF_NOTE_ROUNDSIZE); 2670 desc = (const Elf32_Word *)p; 2671 *arg->has_fctl0 = true; 2672 *arg->fctl0 = desc[0]; 2673 *res = true; 2674 return (true); 2675 } 2676 2677 /* 2678 * Try to find the appropriate ABI-note section for checknote, fetch 2679 * the osreldate and feature control flags for binary from the ELF 2680 * OSABI-note. Only the first page of the image is searched, the same 2681 * as for headers. 2682 */ 2683 static bool 2684 __elfN(check_note)(struct image_params *imgp, Elf_Brandnote *brandnote, 2685 int32_t *osrel, bool *has_fctl0, uint32_t *fctl0) 2686 { 2687 const Elf_Phdr *phdr; 2688 const Elf_Ehdr *hdr; 2689 struct brandnote_cb_arg b_arg; 2690 struct fctl_cb_arg f_arg; 2691 int i, j; 2692 2693 hdr = (const Elf_Ehdr *)imgp->image_header; 2694 phdr = (const Elf_Phdr *)(imgp->image_header + hdr->e_phoff); 2695 b_arg.brandnote = brandnote; 2696 b_arg.osrel = osrel; 2697 f_arg.has_fctl0 = has_fctl0; 2698 f_arg.fctl0 = fctl0; 2699 2700 for (i = 0; i < hdr->e_phnum; i++) { 2701 if (phdr[i].p_type == PT_NOTE && __elfN(parse_notes)(imgp, 2702 &brandnote->hdr, brandnote->vendor, &phdr[i], brandnote_cb, 2703 &b_arg)) { 2704 for (j = 0; j < hdr->e_phnum; j++) { 2705 if (phdr[j].p_type == PT_NOTE && 2706 __elfN(parse_notes)(imgp, &fctl_note, 2707 FREEBSD_ABI_VENDOR, &phdr[j], 2708 note_fctl_cb, &f_arg)) 2709 break; 2710 } 2711 return (true); 2712 } 2713 } 2714 return (false); 2715 2716 } 2717 2718 /* 2719 * Tell kern_execve.c about it, with a little help from the linker. 2720 */ 2721 static struct execsw __elfN(execsw) = { 2722 .ex_imgact = __CONCAT(exec_, __elfN(imgact)), 2723 .ex_name = __XSTRING(__CONCAT(ELF, __ELF_WORD_SIZE)) 2724 }; 2725 EXEC_SET(__CONCAT(elf, __ELF_WORD_SIZE), __elfN(execsw)); 2726 2727 static vm_prot_t 2728 __elfN(trans_prot)(Elf_Word flags) 2729 { 2730 vm_prot_t prot; 2731 2732 prot = 0; 2733 if (flags & PF_X) 2734 prot |= VM_PROT_EXECUTE; 2735 if (flags & PF_W) 2736 prot |= VM_PROT_WRITE; 2737 if (flags & PF_R) 2738 prot |= VM_PROT_READ; 2739 #if __ELF_WORD_SIZE == 32 && (defined(__amd64__) || defined(__i386__)) 2740 if (i386_read_exec && (flags & PF_R)) 2741 prot |= VM_PROT_EXECUTE; 2742 #endif 2743 return (prot); 2744 } 2745 2746 static Elf_Word 2747 __elfN(untrans_prot)(vm_prot_t prot) 2748 { 2749 Elf_Word flags; 2750 2751 flags = 0; 2752 if (prot & VM_PROT_EXECUTE) 2753 flags |= PF_X; 2754 if (prot & VM_PROT_READ) 2755 flags |= PF_R; 2756 if (prot & VM_PROT_WRITE) 2757 flags |= PF_W; 2758 return (flags); 2759 } 2760 2761 vm_size_t 2762 __elfN(stackgap)(struct image_params *imgp, uintptr_t *stack_base) 2763 { 2764 uintptr_t range, rbase, gap; 2765 int pct; 2766 2767 pct = __elfN(aslr_stack_gap); 2768 if (pct == 0) 2769 return (0); 2770 if (pct > 50) 2771 pct = 50; 2772 range = imgp->eff_stack_sz * pct / 100; 2773 arc4rand(&rbase, sizeof(rbase), 0); 2774 gap = rbase % range; 2775 gap &= ~(sizeof(u_long) - 1); 2776 *stack_base -= gap; 2777 return (gap); 2778 } 2779