| /* Test for the memfd_create system call. |
| Copyright (C) 2017-2018 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <stdbool.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <support/check.h> |
| #include <support/support.h> |
| #include <support/test-driver.h> |
| #include <support/xunistd.h> |
| #include <sys/mman.h> |
| |
| /* Return true if the descriptor has the FD_CLOEXEC flag set. */ |
| static bool |
| is_cloexec (int fd) |
| { |
| int flags = fcntl (fd, F_GETFD); |
| TEST_VERIFY (flags >= 0); |
| return flags & FD_CLOEXEC; |
| } |
| |
| /* Return the seals set on FD. */ |
| static int |
| get_seals (int fd) |
| { |
| int flags = fcntl (fd, F_GET_SEALS); |
| TEST_VERIFY (flags >= 0); |
| return flags; |
| } |
| |
| /* Return true if the F_SEAL_SEAL flag is set on the descriptor. */ |
| static bool |
| is_sealed (int fd) |
| { |
| return get_seals (fd) & F_SEAL_SEAL; |
| } |
| |
| static int |
| do_test (void) |
| { |
| /* Initialized by the first call to memfd_create to 0 (memfd_create |
| unsupported) or 1 (memfd_create is implemented in the kernel). |
| Subsequent iterations check that the success/failure state is |
| consistent. */ |
| int supported = -1; |
| |
| for (int do_cloexec = 0; do_cloexec < 2; ++do_cloexec) |
| for (int do_sealing = 0; do_sealing < 2; ++do_sealing) |
| { |
| int flags = 0; |
| if (do_cloexec) |
| flags |= MFD_CLOEXEC; |
| if (do_sealing) |
| flags |= MFD_ALLOW_SEALING; |
| if (test_verbose > 0) |
| printf ("info: memfd_create with flags=0x%x\n", flags); |
| int fd = memfd_create ("tst-memfd_create", flags); |
| if (fd < 0) |
| { |
| if (errno == ENOSYS) |
| { |
| if (supported < 0) |
| { |
| printf ("warning: memfd_create is unsupported\n"); |
| supported = 0; |
| continue; |
| } |
| TEST_VERIFY (supported == 0); |
| continue; |
| } |
| else |
| FAIL_EXIT1 ("memfd_create: %m"); |
| } |
| if (supported < 0) |
| supported = 1; |
| TEST_VERIFY (supported > 0); |
| |
| char *fd_path = xasprintf ("/proc/self/fd/%d", fd); |
| char *link = xreadlink (fd_path); |
| if (test_verbose > 0) |
| printf ("info: memfd link: %s\n", link); |
| TEST_VERIFY (strcmp (link, "memfd:tst-memfd_create (deleted)")); |
| TEST_VERIFY (is_cloexec (fd) == do_cloexec); |
| TEST_VERIFY (is_sealed (fd) == !do_sealing); |
| if (do_sealing) |
| { |
| TEST_VERIFY (fcntl (fd, F_ADD_SEALS, F_SEAL_WRITE) == 0); |
| TEST_VERIFY (!is_sealed (fd)); |
| TEST_VERIFY (get_seals (fd) & F_SEAL_WRITE); |
| TEST_VERIFY (fcntl (fd, F_ADD_SEALS, F_SEAL_SEAL) == 0); |
| TEST_VERIFY (is_sealed (fd)); |
| } |
| xclose (fd); |
| free (fd_path); |
| free (link); |
| } |
| |
| if (supported == 0) |
| return EXIT_UNSUPPORTED; |
| return 0; |
| } |
| |
| #include <support/test-driver.c> |
