src/test/test-fd-util.c

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2
   3 #include <fcntl.h>
   4 #include <sys/eventfd.h>
   5 #include <sys/mount.h>
   6 #include <unistd.h>
   7
   8 #include "alloc-util.h"
   9 #include "data-fd-util.h"
  10 #include "fd-util.h"
  11 #include "fileio.h"
  12 #include "fs-util.h"
  13 #include "macro.h"
  14 #include "memory-util.h"
  15 #include "missing_syscall.h"
  16 #include "mkdir.h"
  17 #include "mount-util.h"
  18 #include "namespace-util.h"
  19 #include "path-util.h"
  20 #include "process-util.h"
  21 #include "random-util.h"
  22 #include "rlimit-util.h"
  23 #include "rm-rf.h"
  24 #include "seccomp-util.h"
  25 #include "serialize.h"
  26 #include "stat-util.h"
  27 #include "string-util.h"
  28 #include "tests.h"
  29 #include "tmpfile-util.h"
  30
  31 TEST(close_many) {
  32         int fds[3];
  33         _cleanup_(unlink_tempfilep) char name0[] = "/tmp/test-close-many.XXXXXX";
  34         _cleanup_(unlink_tempfilep) char name1[] = "/tmp/test-close-many.XXXXXX";
  35         _cleanup_(unlink_tempfilep) char name2[] = "/tmp/test-close-many.XXXXXX";
  36
  37         fds[0] = mkostemp_safe(name0);
  38         fds[1] = mkostemp_safe(name1);
  39         fds[2] = mkostemp_safe(name2);
  40
  41         close_many(fds, 2);
  42
  43         assert_se(fcntl(fds[0], F_GETFD) == -1);
  44         assert_se(fcntl(fds[1], F_GETFD) == -1);
  45         assert_se(fcntl(fds[2], F_GETFD) >= 0);
  46
  47         safe_close(fds[2]);
  48 }
  49
  50 TEST(close_nointr) {
  51         _cleanup_(unlink_tempfilep) char name[] = "/tmp/test-test-close_nointr.XXXXXX";
  52         int fd;
  53
  54         fd = mkostemp_safe(name);
  55         assert_se(fd >= 0);
  56         assert_se(close_nointr(fd) >= 0);
  57         assert_se(close_nointr(fd) < 0);
  58 }
  59
  60 TEST(same_fd) {
  61         _cleanup_close_pair_ int p[2];
  62         _cleanup_close_ int a, b, c;
  63
  64         assert_se(pipe2(p, O_CLOEXEC) >= 0);
  65         assert_se((a = fcntl(p[0], F_DUPFD, 3)) >= 0);
  66         assert_se((b = open("/dev/null", O_RDONLY|O_CLOEXEC)) >= 0);
  67         assert_se((c = fcntl(a, F_DUPFD, 3)) >= 0);
  68
  69         assert_se(same_fd(p[0], p[0]) > 0);
  70         assert_se(same_fd(p[1], p[1]) > 0);
  71         assert_se(same_fd(a, a) > 0);
  72         assert_se(same_fd(b, b) > 0);
  73
  74         assert_se(same_fd(a, p[0]) > 0);
  75         assert_se(same_fd(p[0], a) > 0);
  76         assert_se(same_fd(c, p[0]) > 0);
  77         assert_se(same_fd(p[0], c) > 0);
  78         assert_se(same_fd(a, c) > 0);
  79         assert_se(same_fd(c, a) > 0);
  80
  81         assert_se(same_fd(p[0], p[1]) == 0);
  82         assert_se(same_fd(p[1], p[0]) == 0);
  83         assert_se(same_fd(p[0], b) == 0);
  84         assert_se(same_fd(b, p[0]) == 0);
  85         assert_se(same_fd(p[1], a) == 0);
  86         assert_se(same_fd(a, p[1]) == 0);
  87         assert_se(same_fd(p[1], b) == 0);
  88         assert_se(same_fd(b, p[1]) == 0);
  89
  90         assert_se(same_fd(a, b) == 0);
  91         assert_se(same_fd(b, a) == 0);
  92 }
  93
  94 TEST(open_serialization_fd) {
  95         _cleanup_close_ int fd = -EBADF;
  96
  97         fd = open_serialization_fd("test");
  98         assert_se(fd >= 0);
  99
 100         assert_se(write(fd, "test\n", 5) == 5);
 101 }
 102
 103 TEST(fd_move_above_stdio) {
 104         int original_stdin, new_fd;
 105
 106         original_stdin = fcntl(0, F_DUPFD, 3);
 107         assert_se(original_stdin >= 3);
 108         assert_se(close_nointr(0) != EBADF);
 109
 110         new_fd = open("/dev/null", O_RDONLY);
 111         assert_se(new_fd == 0);
 112
 113         new_fd = fd_move_above_stdio(new_fd);
 114         assert_se(new_fd >= 3);
 115
 116         assert_se(dup(original_stdin) == 0);
 117         assert_se(close_nointr(original_stdin) != EBADF);
 118         assert_se(close_nointr(new_fd) != EBADF);
 119 }
 120
 121 TEST(rearrange_stdio) {
 122         pid_t pid;
 123         int r;
 124
 125         r = safe_fork("rearrange", FORK_WAIT|FORK_LOG, &pid);
 126         assert_se(r >= 0);
 127
 128         if (r == 0) {
 129                 _cleanup_free_ char *path = NULL;
 130                 char buffer[10];
 131
 132                 /* Child */
 133
 134                 safe_close(STDERR_FILENO); /* Let's close an fd < 2, to make it more interesting */
 135
 136                 assert_se(rearrange_stdio(-EBADF, -EBADF, -EBADF) >= 0);
 137
 138                 assert_se(fd_get_path(STDIN_FILENO, &path) >= 0);
 139                 assert_se(path_equal(path, "/dev/null"));
 140                 path = mfree(path);
 141
 142                 assert_se(fd_get_path(STDOUT_FILENO, &path) >= 0);
 143                 assert_se(path_equal(path, "/dev/null"));
 144                 path = mfree(path);
 145
 146                 assert_se(fd_get_path(STDOUT_FILENO, &path) >= 0);
 147                 assert_se(path_equal(path, "/dev/null"));
 148                 path = mfree(path);
 149
 150                 safe_close(STDIN_FILENO);
 151                 safe_close(STDOUT_FILENO);
 152                 safe_close(STDERR_FILENO);
 153
 154                 {
 155                         int pair[2];
 156                         assert_se(pipe(pair) >= 0);
 157                         assert_se(pair[0] == 0);
 158                         assert_se(pair[1] == 1);
 159                         assert_se(fd_move_above_stdio(0) == 3);
 160                 }
 161                 assert_se(open("/dev/full", O_WRONLY|O_CLOEXEC) == 0);
 162                 assert_se(acquire_data_fd("foobar", 6, 0) == 2);
 163
 164                 assert_se(rearrange_stdio(2, 0, 1) >= 0);
 165
 166                 assert_se(write(1, "x", 1) < 0 && errno == ENOSPC);
 167                 assert_se(write(2, "z", 1) == 1);
 168                 assert_se(read(3, buffer, sizeof(buffer)) == 1);
 169                 assert_se(buffer[0] == 'z');
 170                 assert_se(read(0, buffer, sizeof(buffer)) == 6);
 171                 assert_se(memcmp(buffer, "foobar", 6) == 0);
 172
 173                 assert_se(rearrange_stdio(-EBADF, 1, 2) >= 0);
 174                 assert_se(write(1, "a", 1) < 0 && errno == ENOSPC);
 175                 assert_se(write(2, "y", 1) == 1);
 176                 assert_se(read(3, buffer, sizeof(buffer)) == 1);
 177                 assert_se(buffer[0] == 'y');
 178
 179                 assert_se(fd_get_path(0, &path) >= 0);
 180                 assert_se(path_equal(path, "/dev/null"));
 181                 path = mfree(path);
 182
 183                 _exit(EXIT_SUCCESS);
 184         }
 185 }
 186
 187 TEST(read_nr_open) {
 188         log_info("nr-open: %i", read_nr_open());
 189 }
 190
 191 static size_t validate_fds(
 192                 bool opened,
 193                 const int *fds,
 194                 size_t n_fds) {
 195
 196         size_t c = 0;
 197
 198         /* Validates that fds in the specified array are one of the following three:
 199          *
 200          *  1. < 0 (test is skipped) or
 201          *  2. opened (if 'opened' param is true) or
 202          *  3. closed (if 'opened' param is false)
 203          */
 204
 205         for (size_t i = 0; i < n_fds; i++) {
 206                 if (fds[i] < 0)
 207                         continue;
 208
 209                 if (opened)
 210                         assert_se(fcntl(fds[i], F_GETFD) >= 0);
 211                 else
 212                         assert_se(fcntl(fds[i], F_GETFD) < 0 && errno == EBADF);
 213
 214                 c++;
 215         }
 216
 217         return c; /* Return number of fds >= 0 in the array */
 218 }
 219
 220 static void test_close_all_fds_inner(void) {
 221         _cleanup_free_ int *fds = NULL, *keep = NULL;
 222         size_t n_fds, n_keep;
 223         int max_fd;
 224
 225         log_info("/* %s */", __func__);
 226
 227         rlimit_nofile_bump(-1);
 228
 229         max_fd = get_max_fd();
 230         assert_se(max_fd > 10);
 231
 232         if (max_fd > 7000) {
 233                 /* If the worst fallback is activated we need to iterate through all possible fds, hence,
 234                  * let's lower the limit a small bit, so that we don't run for too long. Yes, this undoes the
 235                  * rlimit_nofile_bump() call above partially. */
 236
 237                 (void) setrlimit_closest(RLIMIT_NOFILE, &(struct rlimit) { 7000, 7000 });
 238                 max_fd = 7000;
 239         }
 240
 241         /* Try to use 5000 fds, but when we can't bump the rlimit to make that happen use the whole limit minus 10 */
 242         n_fds = MIN(((size_t) max_fd & ~1U) - 10U, 5000U);
 243         assert_se((n_fds & 1U) == 0U); /* make sure even number of fds */
 244
 245         /* Allocate the determined number of fds, always two at a time */
 246         assert_se(fds = new(int, n_fds));
 247         for (size_t i = 0; i < n_fds; i += 2)
 248                 assert_se(pipe2(fds + i, O_CLOEXEC) >= 0);
 249
 250         /* Validate this worked */
 251         assert_se(validate_fds(true, fds, n_fds) == n_fds);
 252
 253         /* Randomized number of fds to keep, but at most every second */
 254         n_keep = (random_u64() % (n_fds / 2));
 255
 256         /* Now randomly select a number of fds from the array above to keep */
 257         assert_se(keep = new(int, n_keep));
 258         for (size_t k = 0; k < n_keep; k++) {
 259                 for (;;) {
 260                         size_t p;
 261
 262                         p = random_u64() % n_fds;
 263                         if (fds[p] >= 0) {
 264                                 keep[k] = TAKE_FD(fds[p]);
 265                                 break;
 266                         }
 267                 }
 268         }
 269
 270         /* Check that all fds from both arrays are still open, and test how many in each are >= 0 */
 271         assert_se(validate_fds(true, fds, n_fds) == n_fds - n_keep);
 272         assert_se(validate_fds(true, keep, n_keep) == n_keep);
 273
 274         /* Close logging fd first, so that we don't confuse it by closing its fd */
 275         log_close();
 276         log_set_open_when_needed(true);
 277         log_settle_target();
 278
 279         /* Close all but the ones to keep */
 280         assert_se(close_all_fds(keep, n_keep) >= 0);
 281
 282         assert_se(validate_fds(false, fds, n_fds) == n_fds - n_keep);
 283         assert_se(validate_fds(true, keep, n_keep) == n_keep);
 284
 285         /* Close everything else too! */
 286         assert_se(close_all_fds(NULL, 0) >= 0);
 287
 288         assert_se(validate_fds(false, fds, n_fds) == n_fds - n_keep);
 289         assert_se(validate_fds(false, keep, n_keep) == n_keep);
 290
 291         log_set_open_when_needed(false);
 292         log_open();
 293 }
 294
 295 static int seccomp_prohibit_close_range(void) {
 296 #if HAVE_SECCOMP && defined(__SNR_close_range)
 297         _cleanup_(seccomp_releasep) scmp_filter_ctx seccomp = NULL;
 298         int r;
 299
 300         r = seccomp_init_for_arch(&seccomp, SCMP_ARCH_NATIVE, SCMP_ACT_ALLOW);
 301         if (r < 0)
 302                 return log_warning_errno(r, "Failed to acquire seccomp context, ignoring: %m");
 303
 304         r = seccomp_rule_add_exact(
 305                         seccomp,
 306                         SCMP_ACT_ERRNO(EPERM),
 307                         SCMP_SYS(close_range),
 308                         0);
 309         if (r < 0)
 310                 return log_warning_errno(r, "Failed to add close_range() rule, ignoring: %m");
 311
 312         r = seccomp_load(seccomp);
 313         if (r < 0)
 314                 return log_warning_errno(r, "Failed to apply close_range() restrictions, ignoring: %m");
 315
 316         return 0;
 317 #else
 318         return log_warning_errno(SYNTHETIC_ERRNO(EOPNOTSUPP), "Seccomp support or close_range() syscall definition not available.");
 319 #endif
 320 }
 321
 322 TEST(close_all_fds) {
 323         int r;
 324
 325         /* Runs the test four times. Once as is. Once with close_range() syscall blocked via seccomp, once
 326          * with /proc/ overmounted, and once with the combination of both. This should trigger all fallbacks
 327          * in the close_range_all() function. */
 328
 329         r = safe_fork("(caf-plain)", FORK_CLOSE_ALL_FDS|FORK_DEATHSIG|FORK_LOG|FORK_WAIT, NULL);
 330         if (r == 0) {
 331                 test_close_all_fds_inner();
 332                 _exit(EXIT_SUCCESS);
 333         }
 334         assert_se(r >= 0);
 335
 336         if (geteuid() != 0)
 337                 return (void) log_tests_skipped("Lacking privileges for test with close_range() blocked and /proc/ overmounted");
 338
 339         r = safe_fork("(caf-noproc)", FORK_CLOSE_ALL_FDS|FORK_DEATHSIG|FORK_LOG|FORK_WAIT|FORK_NEW_MOUNTNS|FORK_MOUNTNS_SLAVE, NULL);
 340         if (r == 0) {
 341                 r = mount_nofollow_verbose(LOG_WARNING, "tmpfs", "/proc", "tmpfs", 0, NULL);
 342                 if (r < 0)
 343                         log_notice("Overmounting /proc/ didn't work, skipping close_all_fds() with masked /proc/.");
 344                 else
 345                         test_close_all_fds_inner();
 346                 _exit(EXIT_SUCCESS);
 347         }
 348         assert_se(r >= 0);
 349
 350         if (!is_seccomp_available())
 351                 return (void) log_tests_skipped("Seccomp not available");
 352
 353         r = safe_fork("(caf-seccomp)", FORK_CLOSE_ALL_FDS|FORK_DEATHSIG|FORK_LOG|FORK_WAIT, NULL);
 354         if (r == 0) {
 355                 r = seccomp_prohibit_close_range();
 356                 if (r < 0)
 357                         log_notice("Applying seccomp filter didn't work, skipping close_all_fds() test with masked close_range().");
 358                 else
 359                         test_close_all_fds_inner();
 360
 361                 _exit(EXIT_SUCCESS);
 362         }
 363         assert_se(r >= 0);
 364
 365         r = safe_fork("(caf-scnp)", FORK_CLOSE_ALL_FDS|FORK_DEATHSIG|FORK_LOG|FORK_WAIT|FORK_NEW_MOUNTNS|FORK_MOUNTNS_SLAVE, NULL);
 366         if (r == 0) {
 367                 r = seccomp_prohibit_close_range();
 368                 if (r < 0)
 369                         log_notice("Applying seccomp filter didn't work, skipping close_all_fds() test with masked close_range().");
 370                 else {
 371                         r = mount_nofollow_verbose(LOG_WARNING, "tmpfs", "/proc", "tmpfs", 0, NULL);
 372                         if (r < 0)
 373                                 log_notice("Overmounting /proc/ didn't work, skipping close_all_fds() with masked /proc/.");
 374                         else
 375                                 test_close_all_fds_inner();
 376                 }
 377
 378                 test_close_all_fds_inner();
 379                 _exit(EXIT_SUCCESS);
 380         }
 381         assert_se(r >= 0);
 382 }
 383
 384 TEST(format_proc_fd_path) {
 385         assert_se(streq_ptr(FORMAT_PROC_FD_PATH(0), "/proc/self/fd/0"));
 386         assert_se(streq_ptr(FORMAT_PROC_FD_PATH(1), "/proc/self/fd/1"));
 387         assert_se(streq_ptr(FORMAT_PROC_FD_PATH(2), "/proc/self/fd/2"));
 388         assert_se(streq_ptr(FORMAT_PROC_FD_PATH(3), "/proc/self/fd/3"));
 389         assert_se(streq_ptr(FORMAT_PROC_FD_PATH(2147483647), "/proc/self/fd/2147483647"));
 390 }
 391
 392 TEST(fd_reopen) {
 393         _cleanup_close_ int fd1 = -EBADF, fd2 = -EBADF;
 394         struct stat st1, st2;
 395         int fl;
 396
 397         /* Test this with a directory */
 398         fd1 = open("/proc", O_DIRECTORY|O_PATH|O_CLOEXEC);
 399         assert_se(fd1 >= 0);
 400
 401         assert_se(fstat(fd1, &st1) >= 0);
 402         assert_se(S_ISDIR(st1.st_mode));
 403
 404         fl = fcntl(fd1, F_GETFL);
 405         assert_se(fl >= 0);
 406         assert_se(FLAGS_SET(fl, O_DIRECTORY));
 407         assert_se(FLAGS_SET(fl, O_PATH));
 408
 409         /* fd_reopen() with O_NOFOLLOW will systematically fail, since it is implemented via a symlink in /proc/self/fd/ */
 410         assert_se(fd_reopen(fd1, O_RDONLY|O_CLOEXEC|O_NOFOLLOW) == -ELOOP);
 411         assert_se(fd_reopen(fd1, O_RDONLY|O_CLOEXEC|O_DIRECTORY|O_NOFOLLOW) == -ELOOP);
 412
 413         fd2 = fd_reopen(fd1, O_RDONLY|O_DIRECTORY|O_CLOEXEC);  /* drop the O_PATH */
 414         assert_se(fd2 >= 0);
 415
 416         assert_se(fstat(fd2, &st2) >= 0);
 417         assert_se(S_ISDIR(st2.st_mode));
 418         assert_se(stat_inode_same(&st1, &st2));
 419
 420         fl = fcntl(fd2, F_GETFL);
 421         assert_se(fl >= 0);
 422         assert_se(FLAGS_SET(fl, O_DIRECTORY));
 423         assert_se(!FLAGS_SET(fl, O_PATH));
 424
 425         safe_close(fd1);
 426
 427         fd1 = fd_reopen(fd2, O_DIRECTORY|O_PATH|O_CLOEXEC);  /* reacquire the O_PATH */
 428         assert_se(fd1 >= 0);
 429
 430         assert_se(fstat(fd1, &st1) >= 0);
 431         assert_se(S_ISDIR(st1.st_mode));
 432         assert_se(stat_inode_same(&st1, &st2));
 433
 434         fl = fcntl(fd1, F_GETFL);
 435         assert_se(fl >= 0);
 436         assert_se(FLAGS_SET(fl, O_DIRECTORY));
 437         assert_se(FLAGS_SET(fl, O_PATH));
 438
 439         safe_close(fd1);
 440
 441         /* And now, test this with a file. */
 442         fd1 = open("/proc/version", O_PATH|O_CLOEXEC);
 443         assert_se(fd1 >= 0);
 444
 445         assert_se(fstat(fd1, &st1) >= 0);
 446         assert_se(S_ISREG(st1.st_mode));
 447
 448         fl = fcntl(fd1, F_GETFL);
 449         assert_se(fl >= 0);
 450         assert_se(!FLAGS_SET(fl, O_DIRECTORY));
 451         assert_se(FLAGS_SET(fl, O_PATH));
 452
 453         assert_se(fd_reopen(fd1, O_RDONLY|O_DIRECTORY|O_CLOEXEC) == -ENOTDIR);
 454         fd2 = fd_reopen(fd1, O_RDONLY|O_CLOEXEC);  /* drop the O_PATH */
 455         assert_se(fd2 >= 0);
 456
 457         assert_se(fstat(fd2, &st2) >= 0);
 458         assert_se(S_ISREG(st2.st_mode));
 459         assert_se(stat_inode_same(&st1, &st2));
 460
 461         fl = fcntl(fd2, F_GETFL);
 462         assert_se(fl >= 0);
 463         assert_se(!FLAGS_SET(fl, O_DIRECTORY));
 464         assert_se(!FLAGS_SET(fl, O_PATH));
 465
 466         safe_close(fd1);
 467
 468         assert_se(fd_reopen(fd2, O_DIRECTORY|O_PATH|O_CLOEXEC) == -ENOTDIR);
 469         fd1 = fd_reopen(fd2, O_PATH|O_CLOEXEC);  /* reacquire the O_PATH */
 470         assert_se(fd1 >= 0);
 471
 472         assert_se(fstat(fd1, &st1) >= 0);
 473         assert_se(S_ISREG(st1.st_mode));
 474         assert_se(stat_inode_same(&st1, &st2));
 475
 476         fl = fcntl(fd1, F_GETFL);
 477         assert_se(fl >= 0);
 478         assert_se(!FLAGS_SET(fl, O_DIRECTORY));
 479         assert_se(FLAGS_SET(fl, O_PATH));
 480
 481         /* Also check the right error is generated if the fd is already closed */
 482         safe_close(fd1);
 483         assert_se(fd_reopen(fd1, O_RDONLY|O_CLOEXEC) == -EBADF);
 484         fd1 = -EBADF;
 485
 486         /* Validate what happens if we reopen a symlink */
 487         fd1 = open("/proc/self", O_PATH|O_CLOEXEC|O_NOFOLLOW);
 488         assert_se(fd1 >= 0);
 489         assert_se(fstat(fd1, &st1) >= 0);
 490         assert_se(S_ISLNK(st1.st_mode));
 491
 492         fd2 = fd_reopen(fd1, O_PATH|O_CLOEXEC);
 493         assert_se(fd2 >= 0);
 494         assert_se(fstat(fd2, &st2) >= 0);
 495         assert_se(S_ISLNK(st2.st_mode));
 496         assert_se(stat_inode_same(&st1, &st2));
 497         fd2 = safe_close(fd2);
 498
 499         /* So here's the thing: if we have an O_PATH fd to a symlink, we *cannot* convert it to a regular fd
 500          * with that. i.e. you cannot have the VFS follow a symlink pinned via an O_PATH fd. */
 501         assert_se(fd_reopen(fd1, O_RDONLY|O_CLOEXEC) == -ELOOP);
 502 }
 503
 504 TEST(fd_reopen_condition) {
 505         _cleanup_close_ int fd1 = -EBADF, fd3 = -EBADF;
 506         int fd2, fl;
 507
 508         /* Open without O_PATH */
 509         fd1 = open("/usr/", O_RDONLY|O_DIRECTORY|O_CLOEXEC);
 510         assert_se(fd1 >= 0);
 511
 512         fl = fcntl(fd1, F_GETFL);
 513         assert_se(FLAGS_SET(fl, O_DIRECTORY));
 514         assert_se(!FLAGS_SET(fl, O_PATH));
 515
 516         fd2 = fd_reopen_condition(fd1, O_DIRECTORY, O_DIRECTORY|O_PATH, &fd3);
 517         assert_se(fd2 == fd1);
 518         assert_se(fd3 < 0);
 519
 520         /* Switch on O_PATH */
 521         fd2 = fd_reopen_condition(fd1, O_DIRECTORY|O_PATH, O_DIRECTORY|O_PATH, &fd3);
 522         assert_se(fd2 != fd1);
 523         assert_se(fd3 == fd2);
 524
 525         fl = fcntl(fd2, F_GETFL);
 526         assert_se(FLAGS_SET(fl, O_DIRECTORY));
 527         assert_se(FLAGS_SET(fl, O_PATH));
 528
 529         close_and_replace(fd1, fd3);
 530
 531         fd2 = fd_reopen_condition(fd1, O_DIRECTORY|O_PATH, O_DIRECTORY|O_PATH, &fd3);
 532         assert_se(fd2 == fd1);
 533         assert_se(fd3 < 0);
 534
 535         /* Switch off O_PATH again */
 536         fd2 = fd_reopen_condition(fd1, O_DIRECTORY, O_DIRECTORY|O_PATH, &fd3);
 537         assert_se(fd2 != fd1);
 538         assert_se(fd3 == fd2);
 539
 540         fl = fcntl(fd2, F_GETFL);
 541         assert_se(FLAGS_SET(fl, O_DIRECTORY));
 542         assert_se(!FLAGS_SET(fl, O_PATH));
 543
 544         close_and_replace(fd1, fd3);
 545
 546         fd2 = fd_reopen_condition(fd1, O_DIRECTORY, O_DIRECTORY|O_PATH, &fd3);
 547         assert_se(fd2 == fd1);
 548         assert_se(fd3 < 0);
 549 }
 550
 551 TEST(take_fd) {
 552         _cleanup_close_ int fd1 = -EBADF, fd2 = -EBADF;
 553         int array[2] = PIPE_EBADF, i = 0;
 554
 555         assert_se(fd1 == -EBADF);
 556         assert_se(fd2 == -EBADF);
 557
 558         fd1 = eventfd(0, EFD_CLOEXEC);
 559         assert_se(fd1 >= 0);
 560
 561         fd2 = TAKE_FD(fd1);
 562         assert_se(fd1 == -EBADF);
 563         assert_se(fd2 >= 0);
 564
 565         assert_se(array[0] == -EBADF);
 566         assert_se(array[1] == -EBADF);
 567
 568         array[0] = TAKE_FD(fd2);
 569         assert_se(fd1 == -EBADF);
 570         assert_se(fd2 == -EBADF);
 571         assert_se(array[0] >= 0);
 572         assert_se(array[1] == -EBADF);
 573
 574         array[1] = TAKE_FD(array[i]);
 575         assert_se(array[0] == -EBADF);
 576         assert_se(array[1] >= 0);
 577
 578         i = 1 - i;
 579         array[0] = TAKE_FD(*(array + i));
 580         assert_se(array[0] >= 0);
 581         assert_se(array[1] == -EBADF);
 582
 583         i = 1 - i;
 584         fd1 = TAKE_FD(array[i]);
 585         assert_se(fd1 >= 0);
 586         assert_se(array[0] == -EBADF);
 587         assert_se(array[1] == -EBADF);
 588 }
 589
 590 TEST(dir_fd_is_root) {
 591         _cleanup_close_ int fd = -EBADF;
 592         int r;
 593
 594         assert_se(dir_fd_is_root_or_cwd(AT_FDCWD) > 0);
 595
 596         assert_se((fd = open("/", O_CLOEXEC|O_PATH|O_DIRECTORY|O_NOFOLLOW)) >= 0);
 597         assert_se(dir_fd_is_root(fd) > 0);
 598         assert_se(dir_fd_is_root_or_cwd(fd) > 0);
 599
 600         fd = safe_close(fd);
 601
 602         assert_se((fd = open("/usr", O_CLOEXEC|O_PATH|O_DIRECTORY|O_NOFOLLOW)) >= 0);
 603         assert_se(dir_fd_is_root(fd) == 0);
 604         assert_se(dir_fd_is_root_or_cwd(fd) == 0);
 605
 606         r = detach_mount_namespace();
 607         if (r < 0)
 608                 return (void) log_tests_skipped_errno(r, "Failed to detach mount namespace");
 609
 610         _cleanup_(rm_rf_physical_and_freep) char *tmp = NULL;
 611         _cleanup_free_ char *x = NULL, *y = NULL;
 612
 613         assert_se(mkdtemp_malloc("/tmp/test-mkdir-XXXXXX", &tmp) >= 0);
 614         assert_se(x = path_join(tmp, "x"));
 615         assert_se(y = path_join(tmp, "x/y"));
 616         assert_se(mkdir_p(y, 0755) >= 0);
 617         assert_se(mount_nofollow_verbose(LOG_DEBUG, x, y, NULL, MS_BIND, NULL) >= 0);
 618
 619         fd = safe_close(fd);
 620
 621         assert_se((fd = open(tmp, O_CLOEXEC|O_PATH|O_DIRECTORY|O_NOFOLLOW)) >= 0);
 622         assert_se(dir_fd_is_root(fd) == 0);
 623         assert_se(dir_fd_is_root_or_cwd(fd) == 0);
 624
 625         fd = safe_close(fd);
 626
 627         assert_se((fd = open(x, O_CLOEXEC|O_PATH|O_DIRECTORY|O_NOFOLLOW)) >= 0);
 628         assert_se(dir_fd_is_root(fd) == 0);
 629         assert_se(dir_fd_is_root_or_cwd(fd) == 0);
 630
 631         fd = safe_close(fd);
 632
 633         assert_se((fd = open(y, O_CLOEXEC|O_PATH|O_DIRECTORY|O_NOFOLLOW)) >= 0);
 634         assert_se(dir_fd_is_root(fd) == 0);
 635         assert_se(dir_fd_is_root_or_cwd(fd) == 0);
 636 }
 637
 638 TEST(fd_get_path) {
 639         _cleanup_(rm_rf_physical_and_freep) char *t = NULL;
 640         _cleanup_close_ int tfd = -EBADF, fd = -EBADF;
 641         _cleanup_free_ char *p = NULL, *q = NULL, *saved_cwd = NULL;
 642
 643         tfd = mkdtemp_open(NULL, O_PATH, &t);
 644         assert_se(tfd >= 0);
 645         assert_se(fd_get_path(tfd, &p) >= 0);
 646         assert_se(streq(p, t));
 647
 648         p = mfree(p);
 649
 650         assert_se(safe_getcwd(&saved_cwd) >= 0);
 651         assert_se(chdir(t) >= 0);
 652
 653         assert_se(fd_get_path(AT_FDCWD, &p) >= 0);
 654         assert_se(streq(p, t));
 655
 656         p = mfree(p);
 657
 658         assert_se(q = path_join(t, "regular"));
 659         assert_se(touch(q) >= 0);
 660         assert_se(mkdirat_parents(tfd, "subdir/symlink", 0755) >= 0);
 661         assert_se(symlinkat("../regular", tfd, "subdir/symlink") >= 0);
 662         assert_se(symlinkat("subdir", tfd, "symdir") >= 0);
 663
 664         fd = openat(tfd, "regular", O_CLOEXEC|O_PATH);
 665         assert_se(fd >= 0);
 666         assert_se(fd_get_path(fd, &p) >= 0);
 667         assert_se(streq(p, q));
 668
 669         p = mfree(p);
 670         fd = safe_close(fd);
 671
 672         fd = openat(AT_FDCWD, "regular", O_CLOEXEC|O_PATH);
 673         assert_se(fd >= 0);
 674         assert_se(fd_get_path(fd, &p) >= 0);
 675         assert_se(streq(p, q));
 676
 677         p = mfree(p);
 678         fd = safe_close(fd);
 679
 680         fd = openat(tfd, "subdir/symlink", O_CLOEXEC|O_PATH);
 681         assert_se(fd >= 0);
 682         assert_se(fd_verify_regular(fd) >= 0);
 683         assert_se(fd_get_path(fd, &p) >= 0);
 684         assert_se(streq(p, q));
 685
 686         p = mfree(p);
 687         fd = safe_close(fd);
 688
 689         fd = openat(AT_FDCWD, "subdir/symlink", O_CLOEXEC|O_PATH);
 690         assert_se(fd >= 0);
 691         assert_se(fd_verify_regular(fd) >= 0);
 692         assert_se(fd_get_path(fd, &p) >= 0);
 693         assert_se(streq(p, q));
 694
 695         p = mfree(p);
 696         fd = safe_close(fd);
 697
 698         fd = openat(tfd, "symdir//./symlink", O_CLOEXEC|O_PATH);
 699         assert_se(fd >= 0);
 700         assert_se(fd_verify_regular(fd) >= 0);
 701         assert_se(fd_get_path(fd, &p) >= 0);
 702         assert_se(streq(p, q));
 703
 704         p = mfree(p);
 705         fd = safe_close(fd);
 706
 707         fd = openat(AT_FDCWD, "symdir//./symlink", O_CLOEXEC|O_PATH);
 708         assert_se(fd >= 0);
 709         assert_se(fd_verify_regular(fd) >= 0);
 710         assert_se(fd_get_path(fd, &p) >= 0);
 711         assert_se(streq(p, q));
 712
 713         p = mfree(p);
 714         q = mfree(q);
 715         fd = safe_close(fd);
 716
 717         assert_se(q = path_join(t, "subdir/symlink"));
 718         fd = openat(tfd, "subdir/symlink", O_CLOEXEC|O_PATH|O_NOFOLLOW);
 719         assert_se(fd >= 0);
 720         assert_se(fd_verify_regular(fd) == -ELOOP);
 721         assert_se(fd_get_path(fd, &p) >= 0);
 722         assert_se(streq(p, q));
 723
 724         p = mfree(p);
 725         fd = safe_close(fd);
 726
 727         fd = openat(AT_FDCWD, "subdir/symlink", O_CLOEXEC|O_PATH|O_NOFOLLOW);
 728         assert_se(fd >= 0);
 729         assert_se(fd_verify_regular(fd) == -ELOOP);
 730         assert_se(fd_get_path(fd, &p) >= 0);
 731         assert_se(streq(p, q));
 732
 733         p = mfree(p);
 734         fd = safe_close(fd);
 735
 736         fd = openat(tfd, "symdir//./symlink", O_CLOEXEC|O_PATH|O_NOFOLLOW);
 737         assert_se(fd >= 0);
 738         assert_se(fd_verify_regular(fd) == -ELOOP);
 739         assert_se(fd_get_path(fd, &p) >= 0);
 740         assert_se(streq(p, q));
 741
 742         p = mfree(p);
 743         fd = safe_close(fd);
 744
 745         fd = openat(AT_FDCWD, "symdir//./symlink", O_CLOEXEC|O_PATH|O_NOFOLLOW);
 746         assert_se(fd >= 0);
 747         assert_se(fd_verify_regular(fd) == -ELOOP);
 748         assert_se(fd_get_path(fd, &p) >= 0);
 749         assert_se(streq(p, q));
 750
 751         assert_se(chdir(saved_cwd) >= 0);
 752 }
 753
 754 DEFINE_TEST_MAIN(LOG_DEBUG);