1 // SPDX-License-Identifier: GPL-2.0 2 #define _GNU_SOURCE 3 #define __EXPORTED_HEADERS__ 4 5 #include <errno.h> 6 #include <inttypes.h> 7 #include <limits.h> 8 #include <linux/falloc.h> 9 #include <fcntl.h> 10 #include <linux/memfd.h> 11 #include <sched.h> 12 #include <stdio.h> 13 #include <stdlib.h> 14 #include <signal.h> 15 #include <string.h> 16 #include <sys/mman.h> 17 #include <sys/stat.h> 18 #include <sys/syscall.h> 19 #include <sys/wait.h> 20 #include <unistd.h> 21 #include <ctype.h> 22 23 #include "common.h" 24 25 #define MEMFD_STR "memfd:" 26 #define MEMFD_HUGE_STR "memfd-hugetlb:" 27 #define SHARED_FT_STR "(shared file-table)" 28 29 #define MFD_DEF_SIZE 8192 30 #define STACK_SIZE 65536 31 32 #define F_SEAL_EXEC 0x0020 33 34 #define F_WX_SEALS (F_SEAL_SHRINK | \ 35 F_SEAL_GROW | \ 36 F_SEAL_WRITE | \ 37 F_SEAL_FUTURE_WRITE | \ 38 F_SEAL_EXEC) 39 40 #define MFD_NOEXEC_SEAL 0x0008U 41 42 /* 43 * Default is not to test hugetlbfs 44 */ 45 static size_t mfd_def_size = MFD_DEF_SIZE; 46 static const char *memfd_str = MEMFD_STR; 47 48 static ssize_t fd2name(int fd, char *buf, size_t bufsize) 49 { 50 char buf1[PATH_MAX]; 51 int size; 52 ssize_t nbytes; 53 54 size = snprintf(buf1, PATH_MAX, "/proc/self/fd/%d", fd); 55 if (size < 0) { 56 printf("snprintf(%d) failed on %m\n", fd); 57 abort(); 58 } 59 60 /* 61 * reserver one byte for string termination. 62 */ 63 nbytes = readlink(buf1, buf, bufsize-1); 64 if (nbytes == -1) { 65 printf("readlink(%s) failed %m\n", buf1); 66 abort(); 67 } 68 buf[nbytes] = '\0'; 69 return nbytes; 70 } 71 72 static int mfd_assert_new(const char *name, loff_t sz, unsigned int flags) 73 { 74 int r, fd; 75 76 fd = sys_memfd_create(name, flags); 77 if (fd < 0) { 78 printf("memfd_create(\"%s\", %u) failed: %m\n", 79 name, flags); 80 abort(); 81 } 82 83 r = ftruncate(fd, sz); 84 if (r < 0) { 85 printf("ftruncate(%llu) failed: %m\n", (unsigned long long)sz); 86 abort(); 87 } 88 89 return fd; 90 } 91 92 static void sysctl_assert_write(const char *val) 93 { 94 int fd = open("/proc/sys/vm/memfd_noexec", O_WRONLY | O_CLOEXEC); 95 96 if (fd < 0) { 97 printf("open sysctl failed: %m\n"); 98 abort(); 99 } 100 101 if (write(fd, val, strlen(val)) < 0) { 102 printf("write sysctl %s failed: %m\n", val); 103 abort(); 104 } 105 } 106 107 static void sysctl_fail_write(const char *val) 108 { 109 int fd = open("/proc/sys/vm/memfd_noexec", O_WRONLY | O_CLOEXEC); 110 111 if (fd < 0) { 112 printf("open sysctl failed: %m\n"); 113 abort(); 114 } 115 116 if (write(fd, val, strlen(val)) >= 0) { 117 printf("write sysctl %s succeeded, but failure expected\n", 118 val); 119 abort(); 120 } 121 } 122 123 static void sysctl_assert_equal(const char *val) 124 { 125 char *p, buf[128] = {}; 126 int fd = open("/proc/sys/vm/memfd_noexec", O_RDONLY | O_CLOEXEC); 127 128 if (fd < 0) { 129 printf("open sysctl failed: %m\n"); 130 abort(); 131 } 132 133 if (read(fd, buf, sizeof(buf)) < 0) { 134 printf("read sysctl failed: %m\n"); 135 abort(); 136 } 137 138 /* Strip trailing whitespace. */ 139 p = buf; 140 while (!isspace(*p)) 141 p++; 142 *p = '\0'; 143 144 if (strcmp(buf, val) != 0) { 145 printf("unexpected sysctl value: expected %s, got %s\n", val, buf); 146 abort(); 147 } 148 } 149 150 static int mfd_assert_reopen_fd(int fd_in) 151 { 152 int fd; 153 char path[100]; 154 155 sprintf(path, "/proc/self/fd/%d", fd_in); 156 157 fd = open(path, O_RDWR); 158 if (fd < 0) { 159 printf("re-open of existing fd %d failed\n", fd_in); 160 abort(); 161 } 162 163 return fd; 164 } 165 166 static void mfd_fail_new(const char *name, unsigned int flags) 167 { 168 int r; 169 170 r = sys_memfd_create(name, flags); 171 if (r >= 0) { 172 printf("memfd_create(\"%s\", %u) succeeded, but failure expected\n", 173 name, flags); 174 close(r); 175 abort(); 176 } 177 } 178 179 static unsigned int mfd_assert_get_seals(int fd) 180 { 181 int r; 182 183 r = fcntl(fd, F_GET_SEALS); 184 if (r < 0) { 185 printf("GET_SEALS(%d) failed: %m\n", fd); 186 abort(); 187 } 188 189 return (unsigned int)r; 190 } 191 192 static void mfd_assert_has_seals(int fd, unsigned int seals) 193 { 194 char buf[PATH_MAX]; 195 unsigned int s; 196 fd2name(fd, buf, PATH_MAX); 197 198 s = mfd_assert_get_seals(fd); 199 if (s != seals) { 200 printf("%u != %u = GET_SEALS(%s)\n", seals, s, buf); 201 abort(); 202 } 203 } 204 205 static void mfd_assert_add_seals(int fd, unsigned int seals) 206 { 207 int r; 208 unsigned int s; 209 210 s = mfd_assert_get_seals(fd); 211 r = fcntl(fd, F_ADD_SEALS, seals); 212 if (r < 0) { 213 printf("ADD_SEALS(%d, %u -> %u) failed: %m\n", fd, s, seals); 214 abort(); 215 } 216 } 217 218 static void mfd_fail_add_seals(int fd, unsigned int seals) 219 { 220 int r; 221 unsigned int s; 222 223 r = fcntl(fd, F_GET_SEALS); 224 if (r < 0) 225 s = 0; 226 else 227 s = (unsigned int)r; 228 229 r = fcntl(fd, F_ADD_SEALS, seals); 230 if (r >= 0) { 231 printf("ADD_SEALS(%d, %u -> %u) didn't fail as expected\n", 232 fd, s, seals); 233 abort(); 234 } 235 } 236 237 static void mfd_assert_size(int fd, size_t size) 238 { 239 struct stat st; 240 int r; 241 242 r = fstat(fd, &st); 243 if (r < 0) { 244 printf("fstat(%d) failed: %m\n", fd); 245 abort(); 246 } else if (st.st_size != size) { 247 printf("wrong file size %lld, but expected %lld\n", 248 (long long)st.st_size, (long long)size); 249 abort(); 250 } 251 } 252 253 static int mfd_assert_dup(int fd) 254 { 255 int r; 256 257 r = dup(fd); 258 if (r < 0) { 259 printf("dup(%d) failed: %m\n", fd); 260 abort(); 261 } 262 263 return r; 264 } 265 266 static void *mfd_assert_mmap_shared(int fd) 267 { 268 void *p; 269 270 p = mmap(NULL, 271 mfd_def_size, 272 PROT_READ | PROT_WRITE, 273 MAP_SHARED, 274 fd, 275 0); 276 if (p == MAP_FAILED) { 277 printf("mmap() failed: %m\n"); 278 abort(); 279 } 280 281 return p; 282 } 283 284 static void *mfd_assert_mmap_private(int fd) 285 { 286 void *p; 287 288 p = mmap(NULL, 289 mfd_def_size, 290 PROT_READ, 291 MAP_PRIVATE, 292 fd, 293 0); 294 if (p == MAP_FAILED) { 295 printf("mmap() failed: %m\n"); 296 abort(); 297 } 298 299 return p; 300 } 301 302 static int mfd_assert_open(int fd, int flags, mode_t mode) 303 { 304 char buf[512]; 305 int r; 306 307 sprintf(buf, "/proc/self/fd/%d", fd); 308 r = open(buf, flags, mode); 309 if (r < 0) { 310 printf("open(%s) failed: %m\n", buf); 311 abort(); 312 } 313 314 return r; 315 } 316 317 static void mfd_fail_open(int fd, int flags, mode_t mode) 318 { 319 char buf[512]; 320 int r; 321 322 sprintf(buf, "/proc/self/fd/%d", fd); 323 r = open(buf, flags, mode); 324 if (r >= 0) { 325 printf("open(%s) didn't fail as expected\n", buf); 326 abort(); 327 } 328 } 329 330 static void mfd_assert_read(int fd) 331 { 332 char buf[16]; 333 void *p; 334 ssize_t l; 335 336 l = read(fd, buf, sizeof(buf)); 337 if (l != sizeof(buf)) { 338 printf("read() failed: %m\n"); 339 abort(); 340 } 341 342 /* verify PROT_READ *is* allowed */ 343 p = mmap(NULL, 344 mfd_def_size, 345 PROT_READ, 346 MAP_PRIVATE, 347 fd, 348 0); 349 if (p == MAP_FAILED) { 350 printf("mmap() failed: %m\n"); 351 abort(); 352 } 353 munmap(p, mfd_def_size); 354 355 /* verify MAP_PRIVATE is *always* allowed (even writable) */ 356 p = mmap(NULL, 357 mfd_def_size, 358 PROT_READ | PROT_WRITE, 359 MAP_PRIVATE, 360 fd, 361 0); 362 if (p == MAP_FAILED) { 363 printf("mmap() failed: %m\n"); 364 abort(); 365 } 366 munmap(p, mfd_def_size); 367 } 368 369 /* Test that PROT_READ + MAP_SHARED mappings work. */ 370 static void mfd_assert_read_shared(int fd) 371 { 372 void *p; 373 374 /* verify PROT_READ and MAP_SHARED *is* allowed */ 375 p = mmap(NULL, 376 mfd_def_size, 377 PROT_READ, 378 MAP_SHARED, 379 fd, 380 0); 381 if (p == MAP_FAILED) { 382 printf("mmap() failed: %m\n"); 383 abort(); 384 } 385 munmap(p, mfd_def_size); 386 } 387 388 static void mfd_assert_fork_private_write(int fd) 389 { 390 int *p; 391 pid_t pid; 392 393 p = mmap(NULL, 394 mfd_def_size, 395 PROT_READ | PROT_WRITE, 396 MAP_PRIVATE, 397 fd, 398 0); 399 if (p == MAP_FAILED) { 400 printf("mmap() failed: %m\n"); 401 abort(); 402 } 403 404 p[0] = 22; 405 406 pid = fork(); 407 if (pid == 0) { 408 p[0] = 33; 409 exit(0); 410 } else { 411 waitpid(pid, NULL, 0); 412 413 if (p[0] != 22) { 414 printf("MAP_PRIVATE copy-on-write failed: %m\n"); 415 abort(); 416 } 417 } 418 419 munmap(p, mfd_def_size); 420 } 421 422 static void mfd_assert_write(int fd) 423 { 424 ssize_t l; 425 void *p; 426 int r; 427 428 /* 429 * huegtlbfs does not support write, but we want to 430 * verify everything else here. 431 */ 432 if (!hugetlbfs_test) { 433 /* verify write() succeeds */ 434 l = write(fd, "\0\0\0\0", 4); 435 if (l != 4) { 436 printf("write() failed: %m\n"); 437 abort(); 438 } 439 } 440 441 /* verify PROT_READ | PROT_WRITE is allowed */ 442 p = mmap(NULL, 443 mfd_def_size, 444 PROT_READ | PROT_WRITE, 445 MAP_SHARED, 446 fd, 447 0); 448 if (p == MAP_FAILED) { 449 printf("mmap() failed: %m\n"); 450 abort(); 451 } 452 *(char *)p = 0; 453 munmap(p, mfd_def_size); 454 455 /* verify PROT_WRITE is allowed */ 456 p = mmap(NULL, 457 mfd_def_size, 458 PROT_WRITE, 459 MAP_SHARED, 460 fd, 461 0); 462 if (p == MAP_FAILED) { 463 printf("mmap() failed: %m\n"); 464 abort(); 465 } 466 *(char *)p = 0; 467 munmap(p, mfd_def_size); 468 469 /* verify PROT_READ with MAP_SHARED is allowed and a following 470 * mprotect(PROT_WRITE) allows writing */ 471 p = mmap(NULL, 472 mfd_def_size, 473 PROT_READ, 474 MAP_SHARED, 475 fd, 476 0); 477 if (p == MAP_FAILED) { 478 printf("mmap() failed: %m\n"); 479 abort(); 480 } 481 482 r = mprotect(p, mfd_def_size, PROT_READ | PROT_WRITE); 483 if (r < 0) { 484 printf("mprotect() failed: %m\n"); 485 abort(); 486 } 487 488 *(char *)p = 0; 489 munmap(p, mfd_def_size); 490 491 /* verify PUNCH_HOLE works */ 492 r = fallocate(fd, 493 FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, 494 0, 495 mfd_def_size); 496 if (r < 0) { 497 printf("fallocate(PUNCH_HOLE) failed: %m\n"); 498 abort(); 499 } 500 } 501 502 static void mfd_fail_write(int fd) 503 { 504 ssize_t l; 505 void *p; 506 int r; 507 508 /* verify write() fails */ 509 l = write(fd, "data", 4); 510 if (l != -EPERM) { 511 printf("expected EPERM on write(), but got %d: %m\n", (int)l); 512 abort(); 513 } 514 515 /* verify PROT_READ | PROT_WRITE is not allowed */ 516 p = mmap(NULL, 517 mfd_def_size, 518 PROT_READ | PROT_WRITE, 519 MAP_SHARED, 520 fd, 521 0); 522 if (p != MAP_FAILED) { 523 printf("mmap() didn't fail as expected\n"); 524 abort(); 525 } 526 527 /* verify PROT_WRITE is not allowed */ 528 p = mmap(NULL, 529 mfd_def_size, 530 PROT_WRITE, 531 MAP_SHARED, 532 fd, 533 0); 534 if (p != MAP_FAILED) { 535 printf("mmap() didn't fail as expected\n"); 536 abort(); 537 } 538 539 /* Verify PROT_READ with MAP_SHARED with a following mprotect is not 540 * allowed. Note that for r/w the kernel already prevents the mmap. */ 541 p = mmap(NULL, 542 mfd_def_size, 543 PROT_READ, 544 MAP_SHARED, 545 fd, 546 0); 547 if (p != MAP_FAILED) { 548 r = mprotect(p, mfd_def_size, PROT_READ | PROT_WRITE); 549 if (r >= 0) { 550 printf("mmap()+mprotect() didn't fail as expected\n"); 551 abort(); 552 } 553 munmap(p, mfd_def_size); 554 } 555 556 /* verify PUNCH_HOLE fails */ 557 r = fallocate(fd, 558 FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, 559 0, 560 mfd_def_size); 561 if (r >= 0) { 562 printf("fallocate(PUNCH_HOLE) didn't fail as expected\n"); 563 abort(); 564 } 565 } 566 567 static void mfd_assert_shrink(int fd) 568 { 569 int r, fd2; 570 571 r = ftruncate(fd, mfd_def_size / 2); 572 if (r < 0) { 573 printf("ftruncate(SHRINK) failed: %m\n"); 574 abort(); 575 } 576 577 mfd_assert_size(fd, mfd_def_size / 2); 578 579 fd2 = mfd_assert_open(fd, 580 O_RDWR | O_CREAT | O_TRUNC, 581 S_IRUSR | S_IWUSR); 582 close(fd2); 583 584 mfd_assert_size(fd, 0); 585 } 586 587 static void mfd_fail_shrink(int fd) 588 { 589 int r; 590 591 r = ftruncate(fd, mfd_def_size / 2); 592 if (r >= 0) { 593 printf("ftruncate(SHRINK) didn't fail as expected\n"); 594 abort(); 595 } 596 597 mfd_fail_open(fd, 598 O_RDWR | O_CREAT | O_TRUNC, 599 S_IRUSR | S_IWUSR); 600 } 601 602 static void mfd_assert_grow(int fd) 603 { 604 int r; 605 606 r = ftruncate(fd, mfd_def_size * 2); 607 if (r < 0) { 608 printf("ftruncate(GROW) failed: %m\n"); 609 abort(); 610 } 611 612 mfd_assert_size(fd, mfd_def_size * 2); 613 614 r = fallocate(fd, 615 0, 616 0, 617 mfd_def_size * 4); 618 if (r < 0) { 619 printf("fallocate(ALLOC) failed: %m\n"); 620 abort(); 621 } 622 623 mfd_assert_size(fd, mfd_def_size * 4); 624 } 625 626 static void mfd_fail_grow(int fd) 627 { 628 int r; 629 630 r = ftruncate(fd, mfd_def_size * 2); 631 if (r >= 0) { 632 printf("ftruncate(GROW) didn't fail as expected\n"); 633 abort(); 634 } 635 636 r = fallocate(fd, 637 0, 638 0, 639 mfd_def_size * 4); 640 if (r >= 0) { 641 printf("fallocate(ALLOC) didn't fail as expected\n"); 642 abort(); 643 } 644 } 645 646 static void mfd_assert_grow_write(int fd) 647 { 648 static char *buf; 649 ssize_t l; 650 651 /* hugetlbfs does not support write */ 652 if (hugetlbfs_test) 653 return; 654 655 buf = malloc(mfd_def_size * 8); 656 if (!buf) { 657 printf("malloc(%zu) failed: %m\n", mfd_def_size * 8); 658 abort(); 659 } 660 661 l = pwrite(fd, buf, mfd_def_size * 8, 0); 662 if (l != (mfd_def_size * 8)) { 663 printf("pwrite() failed: %m\n"); 664 abort(); 665 } 666 667 mfd_assert_size(fd, mfd_def_size * 8); 668 } 669 670 static void mfd_fail_grow_write(int fd) 671 { 672 static char *buf; 673 ssize_t l; 674 675 /* hugetlbfs does not support write */ 676 if (hugetlbfs_test) 677 return; 678 679 buf = malloc(mfd_def_size * 8); 680 if (!buf) { 681 printf("malloc(%zu) failed: %m\n", mfd_def_size * 8); 682 abort(); 683 } 684 685 l = pwrite(fd, buf, mfd_def_size * 8, 0); 686 if (l == (mfd_def_size * 8)) { 687 printf("pwrite() didn't fail as expected\n"); 688 abort(); 689 } 690 } 691 692 static void mfd_assert_mode(int fd, int mode) 693 { 694 struct stat st; 695 char buf[PATH_MAX]; 696 697 fd2name(fd, buf, PATH_MAX); 698 699 if (fstat(fd, &st) < 0) { 700 printf("fstat(%s) failed: %m\n", buf); 701 abort(); 702 } 703 704 if ((st.st_mode & 07777) != mode) { 705 printf("fstat(%s) wrong file mode 0%04o, but expected 0%04o\n", 706 buf, (int)st.st_mode & 07777, mode); 707 abort(); 708 } 709 } 710 711 static void mfd_assert_chmod(int fd, int mode) 712 { 713 char buf[PATH_MAX]; 714 715 fd2name(fd, buf, PATH_MAX); 716 717 if (fchmod(fd, mode) < 0) { 718 printf("fchmod(%s, 0%04o) failed: %m\n", buf, mode); 719 abort(); 720 } 721 722 mfd_assert_mode(fd, mode); 723 } 724 725 static void mfd_fail_chmod(int fd, int mode) 726 { 727 struct stat st; 728 char buf[PATH_MAX]; 729 730 fd2name(fd, buf, PATH_MAX); 731 732 if (fstat(fd, &st) < 0) { 733 printf("fstat(%s) failed: %m\n", buf); 734 abort(); 735 } 736 737 if (fchmod(fd, mode) == 0) { 738 printf("fchmod(%s, 0%04o) didn't fail as expected\n", 739 buf, mode); 740 abort(); 741 } 742 743 /* verify that file mode bits did not change */ 744 mfd_assert_mode(fd, st.st_mode & 07777); 745 } 746 747 static int idle_thread_fn(void *arg) 748 { 749 sigset_t set; 750 int sig; 751 752 /* dummy waiter; SIGTERM terminates us anyway */ 753 sigemptyset(&set); 754 sigaddset(&set, SIGTERM); 755 sigwait(&set, &sig); 756 757 return 0; 758 } 759 760 static pid_t spawn_thread(unsigned int flags, int (*fn)(void *), void *arg) 761 { 762 uint8_t *stack; 763 pid_t pid; 764 765 stack = malloc(STACK_SIZE); 766 if (!stack) { 767 printf("malloc(STACK_SIZE) failed: %m\n"); 768 abort(); 769 } 770 771 pid = clone(fn, stack + STACK_SIZE, SIGCHLD | flags, arg); 772 if (pid < 0) { 773 printf("clone() failed: %m\n"); 774 abort(); 775 } 776 777 return pid; 778 } 779 780 static void join_thread(pid_t pid) 781 { 782 int wstatus; 783 784 if (waitpid(pid, &wstatus, 0) < 0) { 785 printf("newpid thread: waitpid() failed: %m\n"); 786 abort(); 787 } 788 789 if (WIFEXITED(wstatus) && WEXITSTATUS(wstatus) != 0) { 790 printf("newpid thread: exited with non-zero error code %d\n", 791 WEXITSTATUS(wstatus)); 792 abort(); 793 } 794 795 if (WIFSIGNALED(wstatus)) { 796 printf("newpid thread: killed by signal %d\n", 797 WTERMSIG(wstatus)); 798 abort(); 799 } 800 } 801 802 static pid_t spawn_idle_thread(unsigned int flags) 803 { 804 return spawn_thread(flags, idle_thread_fn, NULL); 805 } 806 807 static void join_idle_thread(pid_t pid) 808 { 809 kill(pid, SIGTERM); 810 waitpid(pid, NULL, 0); 811 } 812 813 /* 814 * Test memfd_create() syscall 815 * Verify syscall-argument validation, including name checks, flag validation 816 * and more. 817 */ 818 static void test_create(void) 819 { 820 char buf[2048]; 821 int fd; 822 823 printf("%s CREATE\n", memfd_str); 824 825 /* test NULL name */ 826 mfd_fail_new(NULL, 0); 827 828 /* test over-long name (not zero-terminated) */ 829 memset(buf, 0xff, sizeof(buf)); 830 mfd_fail_new(buf, 0); 831 832 /* test over-long zero-terminated name */ 833 memset(buf, 0xff, sizeof(buf)); 834 buf[sizeof(buf) - 1] = 0; 835 mfd_fail_new(buf, 0); 836 837 /* verify "" is a valid name */ 838 fd = mfd_assert_new("", 0, 0); 839 close(fd); 840 841 /* verify invalid O_* open flags */ 842 mfd_fail_new("", 0x0100); 843 mfd_fail_new("", ~MFD_CLOEXEC); 844 mfd_fail_new("", ~MFD_ALLOW_SEALING); 845 mfd_fail_new("", ~0); 846 mfd_fail_new("", 0x80000000U); 847 848 /* verify EXEC and NOEXEC_SEAL can't both be set */ 849 mfd_fail_new("", MFD_EXEC | MFD_NOEXEC_SEAL); 850 851 /* verify MFD_CLOEXEC is allowed */ 852 fd = mfd_assert_new("", 0, MFD_CLOEXEC); 853 close(fd); 854 855 /* verify MFD_ALLOW_SEALING is allowed */ 856 fd = mfd_assert_new("", 0, MFD_ALLOW_SEALING); 857 close(fd); 858 859 /* verify MFD_ALLOW_SEALING | MFD_CLOEXEC is allowed */ 860 fd = mfd_assert_new("", 0, MFD_ALLOW_SEALING | MFD_CLOEXEC); 861 close(fd); 862 } 863 864 /* 865 * Test basic sealing 866 * A very basic sealing test to see whether setting/retrieving seals works. 867 */ 868 static void test_basic(void) 869 { 870 int fd; 871 872 printf("%s BASIC\n", memfd_str); 873 874 fd = mfd_assert_new("kern_memfd_basic", 875 mfd_def_size, 876 MFD_CLOEXEC | MFD_ALLOW_SEALING); 877 878 /* add basic seals */ 879 mfd_assert_has_seals(fd, 0); 880 mfd_assert_add_seals(fd, F_SEAL_SHRINK | 881 F_SEAL_WRITE); 882 mfd_assert_has_seals(fd, F_SEAL_SHRINK | 883 F_SEAL_WRITE); 884 885 /* add them again */ 886 mfd_assert_add_seals(fd, F_SEAL_SHRINK | 887 F_SEAL_WRITE); 888 mfd_assert_has_seals(fd, F_SEAL_SHRINK | 889 F_SEAL_WRITE); 890 891 /* add more seals and seal against sealing */ 892 mfd_assert_add_seals(fd, F_SEAL_GROW | F_SEAL_SEAL); 893 mfd_assert_has_seals(fd, F_SEAL_SHRINK | 894 F_SEAL_GROW | 895 F_SEAL_WRITE | 896 F_SEAL_SEAL); 897 898 /* verify that sealing no longer works */ 899 mfd_fail_add_seals(fd, F_SEAL_GROW); 900 mfd_fail_add_seals(fd, 0); 901 902 close(fd); 903 904 /* verify sealing does not work without MFD_ALLOW_SEALING */ 905 fd = mfd_assert_new("kern_memfd_basic", 906 mfd_def_size, 907 MFD_CLOEXEC); 908 mfd_assert_has_seals(fd, F_SEAL_SEAL); 909 mfd_fail_add_seals(fd, F_SEAL_SHRINK | 910 F_SEAL_GROW | 911 F_SEAL_WRITE); 912 mfd_assert_has_seals(fd, F_SEAL_SEAL); 913 close(fd); 914 } 915 916 /* 917 * Test SEAL_WRITE 918 * Test whether SEAL_WRITE actually prevents modifications. 919 */ 920 static void test_seal_write(void) 921 { 922 int fd; 923 924 printf("%s SEAL-WRITE\n", memfd_str); 925 926 fd = mfd_assert_new("kern_memfd_seal_write", 927 mfd_def_size, 928 MFD_CLOEXEC | MFD_ALLOW_SEALING); 929 mfd_assert_has_seals(fd, 0); 930 mfd_assert_add_seals(fd, F_SEAL_WRITE); 931 mfd_assert_has_seals(fd, F_SEAL_WRITE); 932 933 mfd_assert_read(fd); 934 mfd_fail_write(fd); 935 mfd_assert_shrink(fd); 936 mfd_assert_grow(fd); 937 mfd_fail_grow_write(fd); 938 939 close(fd); 940 } 941 942 /* 943 * Test SEAL_FUTURE_WRITE 944 * Test whether SEAL_FUTURE_WRITE actually prevents modifications. 945 */ 946 static void test_seal_future_write(void) 947 { 948 int fd, fd2; 949 void *p; 950 951 printf("%s SEAL-FUTURE-WRITE\n", memfd_str); 952 953 fd = mfd_assert_new("kern_memfd_seal_future_write", 954 mfd_def_size, 955 MFD_CLOEXEC | MFD_ALLOW_SEALING); 956 957 p = mfd_assert_mmap_shared(fd); 958 959 mfd_assert_has_seals(fd, 0); 960 961 mfd_assert_add_seals(fd, F_SEAL_FUTURE_WRITE); 962 mfd_assert_has_seals(fd, F_SEAL_FUTURE_WRITE); 963 964 /* read should pass, writes should fail */ 965 mfd_assert_read(fd); 966 mfd_assert_read_shared(fd); 967 mfd_fail_write(fd); 968 969 fd2 = mfd_assert_reopen_fd(fd); 970 /* read should pass, writes should still fail */ 971 mfd_assert_read(fd2); 972 mfd_assert_read_shared(fd2); 973 mfd_fail_write(fd2); 974 975 mfd_assert_fork_private_write(fd); 976 977 munmap(p, mfd_def_size); 978 close(fd2); 979 close(fd); 980 } 981 982 /* 983 * Test SEAL_SHRINK 984 * Test whether SEAL_SHRINK actually prevents shrinking 985 */ 986 static void test_seal_shrink(void) 987 { 988 int fd; 989 990 printf("%s SEAL-SHRINK\n", memfd_str); 991 992 fd = mfd_assert_new("kern_memfd_seal_shrink", 993 mfd_def_size, 994 MFD_CLOEXEC | MFD_ALLOW_SEALING); 995 mfd_assert_has_seals(fd, 0); 996 mfd_assert_add_seals(fd, F_SEAL_SHRINK); 997 mfd_assert_has_seals(fd, F_SEAL_SHRINK); 998 999 mfd_assert_read(fd); 1000 mfd_assert_write(fd); 1001 mfd_fail_shrink(fd); 1002 mfd_assert_grow(fd); 1003 mfd_assert_grow_write(fd); 1004 1005 close(fd); 1006 } 1007 1008 /* 1009 * Test SEAL_GROW 1010 * Test whether SEAL_GROW actually prevents growing 1011 */ 1012 static void test_seal_grow(void) 1013 { 1014 int fd; 1015 1016 printf("%s SEAL-GROW\n", memfd_str); 1017 1018 fd = mfd_assert_new("kern_memfd_seal_grow", 1019 mfd_def_size, 1020 MFD_CLOEXEC | MFD_ALLOW_SEALING); 1021 mfd_assert_has_seals(fd, 0); 1022 mfd_assert_add_seals(fd, F_SEAL_GROW); 1023 mfd_assert_has_seals(fd, F_SEAL_GROW); 1024 1025 mfd_assert_read(fd); 1026 mfd_assert_write(fd); 1027 mfd_assert_shrink(fd); 1028 mfd_fail_grow(fd); 1029 mfd_fail_grow_write(fd); 1030 1031 close(fd); 1032 } 1033 1034 /* 1035 * Test SEAL_SHRINK | SEAL_GROW 1036 * Test whether SEAL_SHRINK | SEAL_GROW actually prevents resizing 1037 */ 1038 static void test_seal_resize(void) 1039 { 1040 int fd; 1041 1042 printf("%s SEAL-RESIZE\n", memfd_str); 1043 1044 fd = mfd_assert_new("kern_memfd_seal_resize", 1045 mfd_def_size, 1046 MFD_CLOEXEC | MFD_ALLOW_SEALING); 1047 mfd_assert_has_seals(fd, 0); 1048 mfd_assert_add_seals(fd, F_SEAL_SHRINK | F_SEAL_GROW); 1049 mfd_assert_has_seals(fd, F_SEAL_SHRINK | F_SEAL_GROW); 1050 1051 mfd_assert_read(fd); 1052 mfd_assert_write(fd); 1053 mfd_fail_shrink(fd); 1054 mfd_fail_grow(fd); 1055 mfd_fail_grow_write(fd); 1056 1057 close(fd); 1058 } 1059 1060 /* 1061 * Test SEAL_EXEC 1062 * Test fd is created with exec and allow sealing. 1063 * chmod() cannot change x bits after sealing. 1064 */ 1065 static void test_exec_seal(void) 1066 { 1067 int fd; 1068 1069 printf("%s SEAL-EXEC\n", memfd_str); 1070 1071 printf("%s Apply SEAL_EXEC\n", memfd_str); 1072 fd = mfd_assert_new("kern_memfd_seal_exec", 1073 mfd_def_size, 1074 MFD_CLOEXEC | MFD_ALLOW_SEALING | MFD_EXEC); 1075 1076 mfd_assert_mode(fd, 0777); 1077 mfd_assert_chmod(fd, 0644); 1078 1079 mfd_assert_has_seals(fd, 0); 1080 mfd_assert_add_seals(fd, F_SEAL_EXEC); 1081 mfd_assert_has_seals(fd, F_SEAL_EXEC); 1082 1083 mfd_assert_chmod(fd, 0600); 1084 mfd_fail_chmod(fd, 0777); 1085 mfd_fail_chmod(fd, 0670); 1086 mfd_fail_chmod(fd, 0605); 1087 mfd_fail_chmod(fd, 0700); 1088 mfd_fail_chmod(fd, 0100); 1089 mfd_assert_chmod(fd, 0666); 1090 mfd_assert_write(fd); 1091 close(fd); 1092 1093 printf("%s Apply ALL_SEALS\n", memfd_str); 1094 fd = mfd_assert_new("kern_memfd_seal_exec", 1095 mfd_def_size, 1096 MFD_CLOEXEC | MFD_ALLOW_SEALING | MFD_EXEC); 1097 1098 mfd_assert_mode(fd, 0777); 1099 mfd_assert_chmod(fd, 0700); 1100 1101 mfd_assert_has_seals(fd, 0); 1102 mfd_assert_add_seals(fd, F_SEAL_EXEC); 1103 mfd_assert_has_seals(fd, F_WX_SEALS); 1104 1105 mfd_fail_chmod(fd, 0711); 1106 mfd_fail_chmod(fd, 0600); 1107 mfd_fail_write(fd); 1108 close(fd); 1109 } 1110 1111 /* 1112 * Test EXEC_NO_SEAL 1113 * Test fd is created with exec and not allow sealing. 1114 */ 1115 static void test_exec_no_seal(void) 1116 { 1117 int fd; 1118 1119 printf("%s EXEC_NO_SEAL\n", memfd_str); 1120 1121 /* Create with EXEC but without ALLOW_SEALING */ 1122 fd = mfd_assert_new("kern_memfd_exec_no_sealing", 1123 mfd_def_size, 1124 MFD_CLOEXEC | MFD_EXEC); 1125 mfd_assert_mode(fd, 0777); 1126 mfd_assert_has_seals(fd, F_SEAL_SEAL); 1127 mfd_assert_chmod(fd, 0666); 1128 close(fd); 1129 } 1130 1131 /* 1132 * Test memfd_create with MFD_NOEXEC flag 1133 */ 1134 static void test_noexec_seal(void) 1135 { 1136 int fd; 1137 1138 printf("%s NOEXEC_SEAL\n", memfd_str); 1139 1140 /* Create with NOEXEC and ALLOW_SEALING */ 1141 fd = mfd_assert_new("kern_memfd_noexec", 1142 mfd_def_size, 1143 MFD_CLOEXEC | MFD_ALLOW_SEALING | MFD_NOEXEC_SEAL); 1144 mfd_assert_mode(fd, 0666); 1145 mfd_assert_has_seals(fd, F_SEAL_EXEC); 1146 mfd_fail_chmod(fd, 0777); 1147 close(fd); 1148 1149 /* Create with NOEXEC but without ALLOW_SEALING */ 1150 fd = mfd_assert_new("kern_memfd_noexec", 1151 mfd_def_size, 1152 MFD_CLOEXEC | MFD_NOEXEC_SEAL); 1153 mfd_assert_mode(fd, 0666); 1154 mfd_assert_has_seals(fd, F_SEAL_EXEC); 1155 mfd_fail_chmod(fd, 0777); 1156 close(fd); 1157 } 1158 1159 static void test_sysctl_sysctl0(void) 1160 { 1161 int fd; 1162 1163 sysctl_assert_equal("0"); 1164 1165 fd = mfd_assert_new("kern_memfd_sysctl_0_dfl", 1166 mfd_def_size, 1167 MFD_CLOEXEC | MFD_ALLOW_SEALING); 1168 mfd_assert_mode(fd, 0777); 1169 mfd_assert_has_seals(fd, 0); 1170 mfd_assert_chmod(fd, 0644); 1171 close(fd); 1172 } 1173 1174 static void test_sysctl_set_sysctl0(void) 1175 { 1176 sysctl_assert_write("0"); 1177 test_sysctl_sysctl0(); 1178 } 1179 1180 static void test_sysctl_sysctl1(void) 1181 { 1182 int fd; 1183 1184 sysctl_assert_equal("1"); 1185 1186 fd = mfd_assert_new("kern_memfd_sysctl_1_dfl", 1187 mfd_def_size, 1188 MFD_CLOEXEC | MFD_ALLOW_SEALING); 1189 mfd_assert_mode(fd, 0666); 1190 mfd_assert_has_seals(fd, F_SEAL_EXEC); 1191 mfd_fail_chmod(fd, 0777); 1192 close(fd); 1193 1194 fd = mfd_assert_new("kern_memfd_sysctl_1_exec", 1195 mfd_def_size, 1196 MFD_CLOEXEC | MFD_EXEC | MFD_ALLOW_SEALING); 1197 mfd_assert_mode(fd, 0777); 1198 mfd_assert_has_seals(fd, 0); 1199 mfd_assert_chmod(fd, 0644); 1200 close(fd); 1201 1202 fd = mfd_assert_new("kern_memfd_sysctl_1_noexec", 1203 mfd_def_size, 1204 MFD_CLOEXEC | MFD_NOEXEC_SEAL | MFD_ALLOW_SEALING); 1205 mfd_assert_mode(fd, 0666); 1206 mfd_assert_has_seals(fd, F_SEAL_EXEC); 1207 mfd_fail_chmod(fd, 0777); 1208 close(fd); 1209 } 1210 1211 static void test_sysctl_set_sysctl1(void) 1212 { 1213 sysctl_assert_write("1"); 1214 test_sysctl_sysctl1(); 1215 } 1216 1217 static void test_sysctl_sysctl2(void) 1218 { 1219 int fd; 1220 1221 sysctl_assert_equal("2"); 1222 1223 fd = mfd_assert_new("kern_memfd_sysctl_2_dfl", 1224 mfd_def_size, 1225 MFD_CLOEXEC | MFD_ALLOW_SEALING); 1226 mfd_assert_mode(fd, 0666); 1227 mfd_assert_has_seals(fd, F_SEAL_EXEC); 1228 mfd_fail_chmod(fd, 0777); 1229 close(fd); 1230 1231 mfd_fail_new("kern_memfd_sysctl_2_exec", 1232 MFD_CLOEXEC | MFD_EXEC | MFD_ALLOW_SEALING); 1233 1234 fd = mfd_assert_new("kern_memfd_sysctl_2_noexec", 1235 mfd_def_size, 1236 MFD_CLOEXEC | MFD_NOEXEC_SEAL | MFD_ALLOW_SEALING); 1237 mfd_assert_mode(fd, 0666); 1238 mfd_assert_has_seals(fd, F_SEAL_EXEC); 1239 mfd_fail_chmod(fd, 0777); 1240 close(fd); 1241 } 1242 1243 static void test_sysctl_set_sysctl2(void) 1244 { 1245 sysctl_assert_write("2"); 1246 test_sysctl_sysctl2(); 1247 } 1248 1249 static int sysctl_simple_child(void *arg) 1250 { 1251 printf("%s sysctl 0\n", memfd_str); 1252 test_sysctl_set_sysctl0(); 1253 1254 printf("%s sysctl 1\n", memfd_str); 1255 test_sysctl_set_sysctl1(); 1256 1257 printf("%s sysctl 0\n", memfd_str); 1258 test_sysctl_set_sysctl0(); 1259 1260 printf("%s sysctl 2\n", memfd_str); 1261 test_sysctl_set_sysctl2(); 1262 1263 printf("%s sysctl 1\n", memfd_str); 1264 test_sysctl_set_sysctl1(); 1265 1266 printf("%s sysctl 0\n", memfd_str); 1267 test_sysctl_set_sysctl0(); 1268 1269 return 0; 1270 } 1271 1272 /* 1273 * Test sysctl 1274 * A very basic test to make sure the core sysctl semantics work. 1275 */ 1276 static void test_sysctl_simple(void) 1277 { 1278 int pid = spawn_thread(CLONE_NEWPID, sysctl_simple_child, NULL); 1279 1280 join_thread(pid); 1281 } 1282 1283 static int sysctl_nested(void *arg) 1284 { 1285 void (*fn)(void) = arg; 1286 1287 fn(); 1288 return 0; 1289 } 1290 1291 static int sysctl_nested_wait(void *arg) 1292 { 1293 /* Wait for a SIGCONT. */ 1294 kill(getpid(), SIGSTOP); 1295 return sysctl_nested(arg); 1296 } 1297 1298 static void test_sysctl_sysctl1_failset(void) 1299 { 1300 sysctl_fail_write("0"); 1301 test_sysctl_sysctl1(); 1302 } 1303 1304 static void test_sysctl_sysctl2_failset(void) 1305 { 1306 sysctl_fail_write("1"); 1307 test_sysctl_sysctl2(); 1308 1309 sysctl_fail_write("0"); 1310 test_sysctl_sysctl2(); 1311 } 1312 1313 static int sysctl_nested_child(void *arg) 1314 { 1315 int pid; 1316 1317 printf("%s nested sysctl 0\n", memfd_str); 1318 sysctl_assert_write("0"); 1319 /* A further nested pidns works the same. */ 1320 pid = spawn_thread(CLONE_NEWPID, sysctl_simple_child, NULL); 1321 join_thread(pid); 1322 1323 printf("%s nested sysctl 1\n", memfd_str); 1324 sysctl_assert_write("1"); 1325 /* Child inherits our setting. */ 1326 pid = spawn_thread(CLONE_NEWPID, sysctl_nested, test_sysctl_sysctl1); 1327 join_thread(pid); 1328 /* Child cannot raise the setting. */ 1329 pid = spawn_thread(CLONE_NEWPID, sysctl_nested, 1330 test_sysctl_sysctl1_failset); 1331 join_thread(pid); 1332 /* Child can lower the setting. */ 1333 pid = spawn_thread(CLONE_NEWPID, sysctl_nested, 1334 test_sysctl_set_sysctl2); 1335 join_thread(pid); 1336 /* Child lowering the setting has no effect on our setting. */ 1337 test_sysctl_sysctl1(); 1338 1339 printf("%s nested sysctl 2\n", memfd_str); 1340 sysctl_assert_write("2"); 1341 /* Child inherits our setting. */ 1342 pid = spawn_thread(CLONE_NEWPID, sysctl_nested, test_sysctl_sysctl2); 1343 join_thread(pid); 1344 /* Child cannot raise the setting. */ 1345 pid = spawn_thread(CLONE_NEWPID, sysctl_nested, 1346 test_sysctl_sysctl2_failset); 1347 join_thread(pid); 1348 1349 /* Verify that the rules are actually inherited after fork. */ 1350 printf("%s nested sysctl 0 -> 1 after fork\n", memfd_str); 1351 sysctl_assert_write("0"); 1352 1353 pid = spawn_thread(CLONE_NEWPID, sysctl_nested_wait, 1354 test_sysctl_sysctl1_failset); 1355 sysctl_assert_write("1"); 1356 kill(pid, SIGCONT); 1357 join_thread(pid); 1358 1359 printf("%s nested sysctl 0 -> 2 after fork\n", memfd_str); 1360 sysctl_assert_write("0"); 1361 1362 pid = spawn_thread(CLONE_NEWPID, sysctl_nested_wait, 1363 test_sysctl_sysctl2_failset); 1364 sysctl_assert_write("2"); 1365 kill(pid, SIGCONT); 1366 join_thread(pid); 1367 1368 /* 1369 * Verify that the current effective setting is saved on fork, meaning 1370 * that the parent lowering the sysctl doesn't affect already-forked 1371 * children. 1372 */ 1373 printf("%s nested sysctl 2 -> 1 after fork\n", memfd_str); 1374 sysctl_assert_write("2"); 1375 pid = spawn_thread(CLONE_NEWPID, sysctl_nested_wait, 1376 test_sysctl_sysctl2); 1377 sysctl_assert_write("1"); 1378 kill(pid, SIGCONT); 1379 join_thread(pid); 1380 1381 printf("%s nested sysctl 2 -> 0 after fork\n", memfd_str); 1382 sysctl_assert_write("2"); 1383 pid = spawn_thread(CLONE_NEWPID, sysctl_nested_wait, 1384 test_sysctl_sysctl2); 1385 sysctl_assert_write("0"); 1386 kill(pid, SIGCONT); 1387 join_thread(pid); 1388 1389 printf("%s nested sysctl 1 -> 0 after fork\n", memfd_str); 1390 sysctl_assert_write("1"); 1391 pid = spawn_thread(CLONE_NEWPID, sysctl_nested_wait, 1392 test_sysctl_sysctl1); 1393 sysctl_assert_write("0"); 1394 kill(pid, SIGCONT); 1395 join_thread(pid); 1396 1397 return 0; 1398 } 1399 1400 /* 1401 * Test sysctl with nested pid namespaces 1402 * Make sure that the sysctl nesting semantics work correctly. 1403 */ 1404 static void test_sysctl_nested(void) 1405 { 1406 int pid = spawn_thread(CLONE_NEWPID, sysctl_nested_child, NULL); 1407 1408 join_thread(pid); 1409 } 1410 1411 /* 1412 * Test sharing via dup() 1413 * Test that seals are shared between dupped FDs and they're all equal. 1414 */ 1415 static void test_share_dup(char *banner, char *b_suffix) 1416 { 1417 int fd, fd2; 1418 1419 printf("%s %s %s\n", memfd_str, banner, b_suffix); 1420 1421 fd = mfd_assert_new("kern_memfd_share_dup", 1422 mfd_def_size, 1423 MFD_CLOEXEC | MFD_ALLOW_SEALING); 1424 mfd_assert_has_seals(fd, 0); 1425 1426 fd2 = mfd_assert_dup(fd); 1427 mfd_assert_has_seals(fd2, 0); 1428 1429 mfd_assert_add_seals(fd, F_SEAL_WRITE); 1430 mfd_assert_has_seals(fd, F_SEAL_WRITE); 1431 mfd_assert_has_seals(fd2, F_SEAL_WRITE); 1432 1433 mfd_assert_add_seals(fd2, F_SEAL_SHRINK); 1434 mfd_assert_has_seals(fd, F_SEAL_WRITE | F_SEAL_SHRINK); 1435 mfd_assert_has_seals(fd2, F_SEAL_WRITE | F_SEAL_SHRINK); 1436 1437 mfd_assert_add_seals(fd, F_SEAL_SEAL); 1438 mfd_assert_has_seals(fd, F_SEAL_WRITE | F_SEAL_SHRINK | F_SEAL_SEAL); 1439 mfd_assert_has_seals(fd2, F_SEAL_WRITE | F_SEAL_SHRINK | F_SEAL_SEAL); 1440 1441 mfd_fail_add_seals(fd, F_SEAL_GROW); 1442 mfd_fail_add_seals(fd2, F_SEAL_GROW); 1443 mfd_fail_add_seals(fd, F_SEAL_SEAL); 1444 mfd_fail_add_seals(fd2, F_SEAL_SEAL); 1445 1446 close(fd2); 1447 1448 mfd_fail_add_seals(fd, F_SEAL_GROW); 1449 close(fd); 1450 } 1451 1452 /* 1453 * Test sealing with active mmap()s 1454 * Modifying seals is only allowed if no other mmap() refs exist. 1455 */ 1456 static void test_share_mmap(char *banner, char *b_suffix) 1457 { 1458 int fd; 1459 void *p; 1460 1461 printf("%s %s %s\n", memfd_str, banner, b_suffix); 1462 1463 fd = mfd_assert_new("kern_memfd_share_mmap", 1464 mfd_def_size, 1465 MFD_CLOEXEC | MFD_ALLOW_SEALING); 1466 mfd_assert_has_seals(fd, 0); 1467 1468 /* shared/writable ref prevents sealing WRITE, but allows others */ 1469 p = mfd_assert_mmap_shared(fd); 1470 mfd_fail_add_seals(fd, F_SEAL_WRITE); 1471 mfd_assert_has_seals(fd, 0); 1472 mfd_assert_add_seals(fd, F_SEAL_SHRINK); 1473 mfd_assert_has_seals(fd, F_SEAL_SHRINK); 1474 munmap(p, mfd_def_size); 1475 1476 /* readable ref allows sealing */ 1477 p = mfd_assert_mmap_private(fd); 1478 mfd_assert_add_seals(fd, F_SEAL_WRITE); 1479 mfd_assert_has_seals(fd, F_SEAL_WRITE | F_SEAL_SHRINK); 1480 munmap(p, mfd_def_size); 1481 1482 close(fd); 1483 } 1484 1485 /* 1486 * Test sealing with open(/proc/self/fd/%d) 1487 * Via /proc we can get access to a separate file-context for the same memfd. 1488 * This is *not* like dup(), but like a real separate open(). Make sure the 1489 * semantics are as expected and we correctly check for RDONLY / WRONLY / RDWR. 1490 */ 1491 static void test_share_open(char *banner, char *b_suffix) 1492 { 1493 int fd, fd2; 1494 1495 printf("%s %s %s\n", memfd_str, banner, b_suffix); 1496 1497 fd = mfd_assert_new("kern_memfd_share_open", 1498 mfd_def_size, 1499 MFD_CLOEXEC | MFD_ALLOW_SEALING); 1500 mfd_assert_has_seals(fd, 0); 1501 1502 fd2 = mfd_assert_open(fd, O_RDWR, 0); 1503 mfd_assert_add_seals(fd, F_SEAL_WRITE); 1504 mfd_assert_has_seals(fd, F_SEAL_WRITE); 1505 mfd_assert_has_seals(fd2, F_SEAL_WRITE); 1506 1507 mfd_assert_add_seals(fd2, F_SEAL_SHRINK); 1508 mfd_assert_has_seals(fd, F_SEAL_WRITE | F_SEAL_SHRINK); 1509 mfd_assert_has_seals(fd2, F_SEAL_WRITE | F_SEAL_SHRINK); 1510 1511 close(fd); 1512 fd = mfd_assert_open(fd2, O_RDONLY, 0); 1513 1514 mfd_fail_add_seals(fd, F_SEAL_SEAL); 1515 mfd_assert_has_seals(fd, F_SEAL_WRITE | F_SEAL_SHRINK); 1516 mfd_assert_has_seals(fd2, F_SEAL_WRITE | F_SEAL_SHRINK); 1517 1518 close(fd2); 1519 fd2 = mfd_assert_open(fd, O_RDWR, 0); 1520 1521 mfd_assert_add_seals(fd2, F_SEAL_SEAL); 1522 mfd_assert_has_seals(fd, F_SEAL_WRITE | F_SEAL_SHRINK | F_SEAL_SEAL); 1523 mfd_assert_has_seals(fd2, F_SEAL_WRITE | F_SEAL_SHRINK | F_SEAL_SEAL); 1524 1525 close(fd2); 1526 close(fd); 1527 } 1528 1529 /* 1530 * Test sharing via fork() 1531 * Test whether seal-modifications work as expected with forked children. 1532 */ 1533 static void test_share_fork(char *banner, char *b_suffix) 1534 { 1535 int fd; 1536 pid_t pid; 1537 1538 printf("%s %s %s\n", memfd_str, banner, b_suffix); 1539 1540 fd = mfd_assert_new("kern_memfd_share_fork", 1541 mfd_def_size, 1542 MFD_CLOEXEC | MFD_ALLOW_SEALING); 1543 mfd_assert_has_seals(fd, 0); 1544 1545 pid = spawn_idle_thread(0); 1546 mfd_assert_add_seals(fd, F_SEAL_SEAL); 1547 mfd_assert_has_seals(fd, F_SEAL_SEAL); 1548 1549 mfd_fail_add_seals(fd, F_SEAL_WRITE); 1550 mfd_assert_has_seals(fd, F_SEAL_SEAL); 1551 1552 join_idle_thread(pid); 1553 1554 mfd_fail_add_seals(fd, F_SEAL_WRITE); 1555 mfd_assert_has_seals(fd, F_SEAL_SEAL); 1556 1557 close(fd); 1558 } 1559 1560 int main(int argc, char **argv) 1561 { 1562 pid_t pid; 1563 1564 if (argc == 2) { 1565 if (!strcmp(argv[1], "hugetlbfs")) { 1566 unsigned long hpage_size = default_huge_page_size(); 1567 1568 if (!hpage_size) { 1569 printf("Unable to determine huge page size\n"); 1570 abort(); 1571 } 1572 1573 hugetlbfs_test = 1; 1574 memfd_str = MEMFD_HUGE_STR; 1575 mfd_def_size = hpage_size * 2; 1576 } else { 1577 printf("Unknown option: %s\n", argv[1]); 1578 abort(); 1579 } 1580 } 1581 1582 test_create(); 1583 test_basic(); 1584 test_exec_seal(); 1585 test_exec_no_seal(); 1586 test_noexec_seal(); 1587 1588 test_seal_write(); 1589 test_seal_future_write(); 1590 test_seal_shrink(); 1591 test_seal_grow(); 1592 test_seal_resize(); 1593 1594 test_sysctl_simple(); 1595 test_sysctl_nested(); 1596 1597 test_share_dup("SHARE-DUP", ""); 1598 test_share_mmap("SHARE-MMAP", ""); 1599 test_share_open("SHARE-OPEN", ""); 1600 test_share_fork("SHARE-FORK", ""); 1601 1602 /* Run test-suite in a multi-threaded environment with a shared 1603 * file-table. */ 1604 pid = spawn_idle_thread(CLONE_FILES | CLONE_FS | CLONE_VM); 1605 test_share_dup("SHARE-DUP", SHARED_FT_STR); 1606 test_share_mmap("SHARE-MMAP", SHARED_FT_STR); 1607 test_share_open("SHARE-OPEN", SHARED_FT_STR); 1608 test_share_fork("SHARE-FORK", SHARED_FT_STR); 1609 join_idle_thread(pid); 1610 1611 printf("memfd: DONE\n"); 1612 1613 return 0; 1614 } 1615