1 /* Tests for posix_spawn signal handling.
2 Copyright (C) 2021-2023 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 <stdio.h>
20 #include <stdlib.h>
21 #include <getopt.h>
22 #include <spawn.h>
23 #include <fcntl.h>
24 #include <sys/wait.h>
25 #include <dirent.h>
26 #include <stdbool.h>
27 #include <errno.h>
28 #include <limits.h>
29
30 #include <support/check.h>
31 #include <support/xunistd.h>
32 #include <support/support.h>
33
34 #include <arch-fd_to_filename.h>
35 #include <array_length.h>
36
37 /* Nonzero if the program gets called via `exec'. */
38 static int restart;
39
40 /* Hold the four initial argument used to respawn the process, plus
41 the extra '--direct' and '--restart', and a final NULL. */
42 static char *initial_argv[7];
43 static int initial_argv_count;
44
45 #define CMDLINE_OPTIONS \
46 { "restart", no_argument, &restart, 1 },
47
48 #define NFDS 100
49
50 static int
51 parse_fd (const char *str)
52 {
53 char *endptr;
54 long unsigned int fd = strtoul (str, &endptr, 10);
55 if (*endptr != '\0' || fd > INT_MAX)
56 FAIL_EXIT1 ("invalid file descriptor value: %s", str);
57 return fd;
58 }
59
60 /* Called on process re-execution. The arguments are the expected opened
61 file descriptors. */
62 _Noreturn static void
63 handle_restart (int argc, char *argv[])
64 {
65 TEST_VERIFY (argc > 0);
66 int lowfd = parse_fd (argv[0]);
67
68 size_t nfds = argc > 1 ? argc - 1 : 0;
69 struct fd_t
70 {
71 int fd;
72 _Bool found;
73 } *fds = xmalloc (sizeof (struct fd_t) * nfds);
74 for (int i = 0; i < nfds; i++)
75 {
76 fds[i].fd = parse_fd (argv[i + 1]);
77 fds[i].found = false;
78 }
79
80 DIR *dirp = opendir (FD_TO_FILENAME_PREFIX);
81 if (dirp == NULL)
82 FAIL_EXIT1 ("opendir (\"" FD_TO_FILENAME_PREFIX "\"): %m");
83
84 while (true)
85 {
86 errno = 0;
87 struct dirent64 *e = readdir64 (dirp);
88 if (e == NULL)
89 {
90 if (errno != 0)
91 FAIL_EXIT1 ("readdir: %m");
92 break;
93 }
94
95 if (e->d_name[0] == '.')
96 continue;
97
98 char *endptr;
99 long int fd = strtol (e->d_name, &endptr, 10);
100 if (*endptr != '\0' || fd < 0 || fd > INT_MAX)
101 FAIL_EXIT1 ("readdir: invalid file descriptor name: /proc/self/fd/%s",
102 e->d_name);
103
104 /* Ignore the descriptors not in the range of the opened files. */
105 if (fd < lowfd || fd == dirfd (dirp))
106 continue;
107
108 bool found = false;
109 for (int i = 0; i < nfds; i++)
110 if (fds[i].fd == fd)
111 fds[i].found = found = true;
112
113 if (!found)
114 {
115 char *path = xasprintf ("/proc/self/fd/%s", e->d_name);
116 char *resolved = xreadlink (path);
117 FAIL_EXIT1 ("unexpected open file descriptor %ld: %s", fd, resolved);
118 }
119 }
120 closedir (dirp);
121
122 for (int i = 0; i < nfds; i++)
123 if (!fds[i].found)
124 FAIL_EXIT1 ("file descriptor %d not opened", fds[i].fd);
125
126 free (fds);
127
128 exit (EXIT_SUCCESS);
129 }
130
131 static void
132 spawn_closefrom_test (posix_spawn_file_actions_t *fa, int lowfd, int highfd,
133 int *extrafds, size_t nextrafds)
134 {
135 /* 3 or 7 elements from initial_argv:
136 + path to ld.so optional
137 + --library-path optional
138 + the library path optional
139 + application name
140 + --direct
141 + --restart
142 + lowest opened file descriptor
143 + up to 2 * maximum_fd arguments (the expected open file descriptors),
144 plus NULL. */
145
146 int argv_size = initial_argv_count + 2 * NFDS + 1;
147 char *args[argv_size];
148 int argc = 0;
149
150 for (char **arg = initial_argv; *arg != NULL; arg++)
151 args[argc++] = *arg;
152
153 args[argc++] = xasprintf ("%d", lowfd);
154
155 for (int i = lowfd; i < highfd; i++)
156 args[argc++] = xasprintf ("%d", i);
157
158 for (int i = 0; i < nextrafds; i++)
159 args[argc++] = xasprintf ("%d", extrafds[i]);
160
161 args[argc] = NULL;
162 TEST_VERIFY (argc < argv_size);
163
164 pid_t pid;
165 int status;
166
167 TEST_COMPARE (posix_spawn (&pid, args[0], fa, NULL, args, environ), 0);
168 TEST_COMPARE (xwaitpid (pid, &status, 0), pid);
169 TEST_VERIFY (WIFEXITED (status));
170 TEST_VERIFY (!WIFSIGNALED (status));
171 TEST_COMPARE (WEXITSTATUS (status), 0);
172 }
173
174 static void
175 do_test_closefrom (void)
176 {
177 int lowfd = support_open_dev_null_range (NFDS, O_RDONLY, 0600);
178 const int half_fd = lowfd + NFDS / 2;
179
180 /* Close half of the descriptors and check result. */
181 {
182 posix_spawn_file_actions_t fa;
183 TEST_COMPARE (posix_spawn_file_actions_init (&fa), 0);
184
185 int ret = posix_spawn_file_actions_addclosefrom_np (&fa, half_fd);
186 if (ret == EINVAL)
187 /* Hurd currently does not support closefrom fileaction. */
188 FAIL_UNSUPPORTED ("posix_spawn_file_actions_addclosefrom_np unsupported");
189 TEST_COMPARE (ret, 0);
190
191 spawn_closefrom_test (&fa, lowfd, half_fd, NULL, 0);
192
193 TEST_COMPARE (posix_spawn_file_actions_destroy (&fa), 0);
194 }
195
196 /* Create some gaps, close up to a threshold, and check result. */
197 xclose (lowfd + 57);
198 xclose (lowfd + 78);
199 xclose (lowfd + 81);
200 xclose (lowfd + 82);
201 xclose (lowfd + 84);
202 xclose (lowfd + 90);
203
204 {
205 posix_spawn_file_actions_t fa;
206 TEST_COMPARE (posix_spawn_file_actions_init (&fa), 0);
207
208 TEST_COMPARE (posix_spawn_file_actions_addclosefrom_np (&fa, half_fd), 0);
209
210 spawn_closefrom_test (&fa, lowfd, half_fd, NULL, 0);
211
212 TEST_COMPARE (posix_spawn_file_actions_destroy (&fa), 0);
213 }
214
215 /* Close the remaining but the last one. */
216 {
217 posix_spawn_file_actions_t fa;
218 TEST_COMPARE (posix_spawn_file_actions_init (&fa), 0);
219
220 TEST_COMPARE (posix_spawn_file_actions_addclosefrom_np (&fa, lowfd + 1), 0);
221
222 spawn_closefrom_test (&fa, lowfd, lowfd + 1, NULL, 0);
223
224 TEST_COMPARE (posix_spawn_file_actions_destroy (&fa), 0);
225 }
226
227 /* Close everything. */
228 {
229 posix_spawn_file_actions_t fa;
230 TEST_COMPARE (posix_spawn_file_actions_init (&fa), 0);
231
232 TEST_COMPARE (posix_spawn_file_actions_addclosefrom_np (&fa, lowfd), 0);
233
234 spawn_closefrom_test (&fa, lowfd, lowfd, NULL, 0);
235
236 TEST_COMPARE (posix_spawn_file_actions_destroy (&fa), 0);
237 }
238
239 /* Close a range and add some file actions. */
240 {
241 posix_spawn_file_actions_t fa;
242 TEST_COMPARE (posix_spawn_file_actions_init (&fa), 0);
243
244 TEST_COMPARE (posix_spawn_file_actions_addclosefrom_np (&fa, lowfd + 1), 0);
245 TEST_COMPARE (posix_spawn_file_actions_addopen (&fa, lowfd, "/dev/null",
246 0666, O_RDONLY), 0);
247 TEST_COMPARE (posix_spawn_file_actions_adddup2 (&fa, lowfd, lowfd + 1), 0);
248 TEST_COMPARE (posix_spawn_file_actions_addopen (&fa, lowfd, "/dev/null",
249 0666, O_RDONLY), 0);
250
251 spawn_closefrom_test (&fa, lowfd, lowfd, (int[]){lowfd, lowfd + 1}, 2);
252
253 TEST_COMPARE (posix_spawn_file_actions_destroy (&fa), 0);
254 }
255 }
256
257 static int
258 do_test (int argc, char *argv[])
259 {
260 /* We must have either:
261
262 - one or four parameters if called initially:
263 + argv[1]: path for ld.so optional
264 + argv[2]: "--library-path" optional
265 + argv[3]: the library path optional
266 + argv[4]: the application name
267
268 - six parameters left if called through re-execution:
269 + argv[1]: the application name
270 + argv[2]: the lowest file descriptor expected
271 + argv[3]: first expected open file descriptor optional
272 + argv[n]: last expected open file descriptor optional
273
274 * When built with --enable-hardcoded-path-in-tests or issued without
275 using the loader directly. */
276
277 if (restart)
278 /* Ignore the application name. */
279 handle_restart (argc - 1, &argv[1]);
280
281 TEST_VERIFY_EXIT (argc == 2 || argc == 5);
282
283 int i;
284
285 for (i = 0; i < argc - 1; i++)
286 initial_argv[i] = argv[i + 1];
287 initial_argv[i++] = (char *) "--direct";
288 initial_argv[i++] = (char *) "--restart";
289
290 initial_argv_count = i;
291
292 do_test_closefrom ();
293
294 return 0;
295 }
296
297 #define TEST_FUNCTION_ARGV do_test
298 #include <support/test-driver.c>