Warning: That file was not part of the compilation database. It may have many parsing errors.

1/* Test for the memfd_create system call.
2 Copyright (C) 2017-2019 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <http://www.gnu.org/licenses/>. */
18
19#include <errno.h>
20#include <fcntl.h>
21#include <stdbool.h>
22#include <stdio.h>
23#include <stdlib.h>
24#include <string.h>
25#include <support/check.h>
26#include <support/support.h>
27#include <support/test-driver.h>
28#include <support/xunistd.h>
29#include <sys/mman.h>
30
31/* Return true if the descriptor has the FD_CLOEXEC flag set. */
32static bool
33is_cloexec (int fd)
34{
35 int flags = fcntl (fd, F_GETFD);
36 TEST_VERIFY (flags >= 0);
37 return flags & FD_CLOEXEC;
38}
39
40/* Return the seals set on FD. */
41static int
42get_seals (int fd)
43{
44 int flags = fcntl (fd, F_GET_SEALS);
45 TEST_VERIFY (flags >= 0);
46 return flags;
47}
48
49/* Return true if the F_SEAL_SEAL flag is set on the descriptor. */
50static bool
51is_sealed (int fd)
52{
53 return get_seals (fd) & F_SEAL_SEAL;
54}
55
56static int
57do_test (void)
58{
59 /* Initialized by the first call to memfd_create to 0 (memfd_create
60 unsupported) or 1 (memfd_create is implemented in the kernel).
61 Subsequent iterations check that the success/failure state is
62 consistent. */
63 int supported = -1;
64
65 for (int do_cloexec = 0; do_cloexec < 2; ++do_cloexec)
66 for (int do_sealing = 0; do_sealing < 2; ++do_sealing)
67 {
68 int flags = 0;
69 if (do_cloexec)
70 flags |= MFD_CLOEXEC;
71 if (do_sealing)
72 flags |= MFD_ALLOW_SEALING;
73 if (test_verbose > 0)
74 printf ("info: memfd_create with flags=0x%x\n", flags);
75 int fd = memfd_create ("tst-memfd_create", flags);
76 if (fd < 0)
77 {
78 if (errno == ENOSYS)
79 {
80 if (supported < 0)
81 {
82 printf ("warning: memfd_create is unsupported\n");
83 supported = 0;
84 continue;
85 }
86 TEST_VERIFY (supported == 0);
87 continue;
88 }
89 else
90 FAIL_EXIT1 ("memfd_create: %m");
91 }
92 if (supported < 0)
93 supported = 1;
94 TEST_VERIFY (supported > 0);
95
96 char *fd_path = xasprintf ("/proc/self/fd/%d", fd);
97 char *link = xreadlink (fd_path);
98 if (test_verbose > 0)
99 printf ("info: memfd link: %s\n", link);
100 TEST_VERIFY (strcmp (link, "memfd:tst-memfd_create (deleted)"));
101 TEST_VERIFY (is_cloexec (fd) == do_cloexec);
102 TEST_VERIFY (is_sealed (fd) == !do_sealing);
103 if (do_sealing)
104 {
105 TEST_VERIFY (fcntl (fd, F_ADD_SEALS, F_SEAL_WRITE) == 0);
106 TEST_VERIFY (!is_sealed (fd));
107 TEST_VERIFY (get_seals (fd) & F_SEAL_WRITE);
108 TEST_VERIFY (fcntl (fd, F_ADD_SEALS, F_SEAL_SEAL) == 0);
109 TEST_VERIFY (is_sealed (fd));
110 }
111 xclose (fd);
112 free (fd_path);
113 free (link);
114 }
115
116 if (supported == 0)
117 return EXIT_UNSUPPORTED;
118 return 0;
119}
120
121#include <support/test-driver.c>
122

Warning: That file was not part of the compilation database. It may have many parsing errors.