1 /* Copyright (C) 2017-2023 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>. */
18 /* Verify that tunables correctly filter out unsafe tunables like
19 glibc.malloc.check and glibc.malloc.mmap_threshold but also retain
20 glibc.malloc.mmap_threshold in an unprivileged child. */
22 /* This is compiled as part of the testsuite but needs to see
38 #include <array_length.h>
40 #include <support/check.h>
41 #include <support/support.h>
42 #include <support/test-driver.h>
43 #include <support/capture_subprocess.h>
45 const char *teststrings[] =
47 "glibc.malloc.check=2:glibc.malloc.mmap_threshold=4096",
48 "glibc.malloc.check=2:glibc.malloc.check=2:glibc.malloc.mmap_threshold=4096",
49 "glibc.malloc.check=2:glibc.malloc.mmap_threshold=4096:glibc.malloc.check=2",
50 "glibc.malloc.perturb=0x800",
51 "glibc.malloc.perturb=0x800:glibc.malloc.mmap_threshold=4096",
52 "glibc.malloc.perturb=0x800:not_valid.malloc.check=2:glibc.malloc.mmap_threshold=4096",
53 "glibc.not_valid.check=2:glibc.malloc.mmap_threshold=4096",
54 "not_valid.malloc.check=2:glibc.malloc.mmap_threshold=4096",
55 "glibc.malloc.mmap_threshold=glibc.malloc.mmap_threshold=4096",
56 "glibc.malloc.check=2",
57 "glibc.malloc.garbage=2:glibc.maoc.mmap_threshold=4096:glibc.malloc.check=2",
58 "glibc.malloc.check=4:glibc.malloc.garbage=2:glibc.maoc.mmap_threshold=4096",
59 ":glibc.malloc.garbage=2:glibc.malloc.check=1",
60 "glibc.malloc.check=1:glibc.malloc.check=2",
61 "not_valid.malloc.check=2",
62 "glibc.not_valid.check=2",
65 const char *resultstrings[] =
67 "glibc.malloc.mmap_threshold=4096",
68 "glibc.malloc.mmap_threshold=4096",
69 "glibc.malloc.mmap_threshold=4096",
70 "glibc.malloc.perturb=0x800",
71 "glibc.malloc.perturb=0x800:glibc.malloc.mmap_threshold=4096",
72 "glibc.malloc.perturb=0x800:glibc.malloc.mmap_threshold=4096",
73 "glibc.malloc.mmap_threshold=4096",
74 "glibc.malloc.mmap_threshold=4096",
75 "glibc.malloc.mmap_threshold=glibc.malloc.mmap_threshold=4096",
88 const char *val = getenv ("GLIBC_TUNABLES");
91 printf (" [%d] GLIBC_TUNABLES is %s\n", off, val);
93 if (val != NULL && strcmp (val, resultstrings[off]) == 0)
97 printf (" [%d] Unexpected GLIBC_TUNABLES VALUE %s, expected %s\n",
98 off, val, resultstrings[off]);
100 printf (" [%d] GLIBC_TUNABLES environment variable absent\n", off);
108 printf ("[%d] GLIBC_TUNABLES not cleared\n", off);
116 do_test (int argc, char **argv)
118 /* Setgid child process. */
121 if (getgid () == getegid ())
122 /* This can happen if the file system is mounted nosuid. */
123 FAIL_UNSUPPORTED ("SGID failed: GID and EGID match (%jd)\n",
124 (intmax_t) getgid ());
126 int ret = test_child (atoi (argv[1]));
131 /* Special return code to make sure that the child executed all the way
138 for (int i = 0; i < array_length (teststrings); i++)
140 char buf[INT_BUFSIZE_BOUND (int)];
142 printf ("[%d] Spawned test for %s\n", i, teststrings[i]);
143 snprintf (buf, sizeof (buf), "%d\n", i);
145 if (setenv ("GLIBC_TUNABLES", teststrings[i], 1) != 0)
147 printf (" [%d] Failed to set GLIBC_TUNABLES: %m", i);
148 support_record_failure ();
152 int status = support_capture_subprogram_self_sgid (buf);
154 /* Bail out early if unsupported. */
155 if (WEXITSTATUS (status) == EXIT_UNSUPPORTED)
156 return EXIT_UNSUPPORTED;
158 if (WEXITSTATUS (status) != 42)
160 printf (" [%d] child failed with status %d\n", i,
161 WEXITSTATUS (status));
162 support_record_failure ();
169 #define TEST_FUNCTION_ARGV do_test
170 #include <support/test-driver.c>