1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Author: Aleksa Sarai <cyphar@cyphar.com>
4 * Copyright (C) 2018-2019 SUSE LLC.
5 */
6
7#define _GNU_SOURCE
8#include <fcntl.h>
9#include <sched.h>
10#include <sys/stat.h>
11#include <sys/types.h>
12#include <sys/mount.h>
13#include <stdlib.h>
14#include <stdbool.h>
15#include <string.h>
16
17#include "../kselftest.h"
18#include "helpers.h"
19
20/*
21 * Construct a test directory with the following structure:
22 *
23 * root/
24 * |-- procexe -> /proc/self/exe
25 * |-- procroot -> /proc/self/root
26 * |-- root/
27 * |-- mnt/ [mountpoint]
28 * | |-- self -> ../mnt/
29 * | `-- absself -> /mnt/
30 * |-- etc/
31 * | `-- passwd
32 * |-- creatlink -> /newfile3
33 * |-- reletc -> etc/
34 * |-- relsym -> etc/passwd
35 * |-- absetc -> /etc/
36 * |-- abssym -> /etc/passwd
37 * |-- abscheeky -> /cheeky
38 * `-- cheeky/
39 * |-- absself -> /
40 * |-- self -> ../../root/
41 * |-- garbageself -> /../../root/
42 * |-- passwd -> ../cheeky/../cheeky/../etc/../etc/passwd
43 * |-- abspasswd -> /../cheeky/../cheeky/../etc/../etc/passwd
44 * |-- dotdotlink -> ../../../../../../../../../../../../../../etc/passwd
45 * `-- garbagelink -> /../../../../../../../../../../../../../../etc/passwd
46 */
47int setup_testdir(void)
48{
49 int dfd, tmpfd;
50 char dirname[] = "/tmp/ksft-openat2-testdir.XXXXXX";
51
52 /* Unshare and make /tmp a new directory. */
53 E_unshare(CLONE_NEWNS);
54 E_mount("", "/tmp", "", MS_PRIVATE, "");
55
56 /* Make the top-level directory. */
57 if (!mkdtemp(dirname))
58 ksft_exit_fail_msg(msg: "setup_testdir: failed to create tmpdir\n");
59 dfd = open(dirname, O_PATH | O_DIRECTORY);
60 if (dfd < 0)
61 ksft_exit_fail_msg(msg: "setup_testdir: failed to open tmpdir\n");
62
63 /* A sub-directory which is actually used for tests. */
64 E_mkdirat(dfd, "root", 0755);
65 tmpfd = openat(dfd, "root", O_PATH | O_DIRECTORY);
66 if (tmpfd < 0)
67 ksft_exit_fail_msg(msg: "setup_testdir: failed to open tmpdir\n");
68 close(dfd);
69 dfd = tmpfd;
70
71 E_symlinkat("/proc/self/exe", dfd, "procexe");
72 E_symlinkat("/proc/self/root", dfd, "procroot");
73 E_mkdirat(dfd, "root", 0755);
74
75 /* There is no mountat(2), so use chdir. */
76 E_mkdirat(dfd, "mnt", 0755);
77 E_fchdir(dfd);
78 E_mount("tmpfs", "./mnt", "tmpfs", MS_NOSUID | MS_NODEV, "");
79 E_symlinkat("../mnt/", dfd, "mnt/self");
80 E_symlinkat("/mnt/", dfd, "mnt/absself");
81
82 E_mkdirat(dfd, "etc", 0755);
83 E_touchat(dfd, "etc/passwd");
84
85 E_symlinkat("/newfile3", dfd, "creatlink");
86 E_symlinkat("etc/", dfd, "reletc");
87 E_symlinkat("etc/passwd", dfd, "relsym");
88 E_symlinkat("/etc/", dfd, "absetc");
89 E_symlinkat("/etc/passwd", dfd, "abssym");
90 E_symlinkat("/cheeky", dfd, "abscheeky");
91
92 E_mkdirat(dfd, "cheeky", 0755);
93
94 E_symlinkat("/", dfd, "cheeky/absself");
95 E_symlinkat("../../root/", dfd, "cheeky/self");
96 E_symlinkat("/../../root/", dfd, "cheeky/garbageself");
97
98 E_symlinkat("../cheeky/../etc/../etc/passwd", dfd, "cheeky/passwd");
99 E_symlinkat("/../cheeky/../etc/../etc/passwd", dfd, "cheeky/abspasswd");
100
101 E_symlinkat("../../../../../../../../../../../../../../etc/passwd",
102 dfd, "cheeky/dotdotlink");
103 E_symlinkat("/../../../../../../../../../../../../../../etc/passwd",
104 dfd, "cheeky/garbagelink");
105
106 return dfd;
107}
108
109struct basic_test {
110 const char *name;
111 const char *dir;
112 const char *path;
113 struct open_how how;
114 bool pass;
115 union {
116 int err;
117 const char *path;
118 } out;
119};
120
121#define NUM_OPENAT2_OPATH_TESTS 88
122
123void test_openat2_opath_tests(void)
124{
125 int rootfd, hardcoded_fd;
126 char *procselfexe, *hardcoded_fdpath;
127
128 E_asprintf(&procselfexe, "/proc/%d/exe", getpid());
129 rootfd = setup_testdir();
130
131 hardcoded_fd = open("/dev/null", O_RDONLY);
132 E_assert(hardcoded_fd >= 0, "open fd to hardcode");
133 E_asprintf(&hardcoded_fdpath, "self/fd/%d", hardcoded_fd);
134
135 struct basic_test tests[] = {
136 /** RESOLVE_BENEATH **/
137 /* Attempts to cross dirfd should be blocked. */
138 { .name = "[beneath] jump to /",
139 .path = "/", .how.resolve = RESOLVE_BENEATH,
140 .out.err = -EXDEV, .pass = false },
141 { .name = "[beneath] absolute link to $root",
142 .path = "cheeky/absself", .how.resolve = RESOLVE_BENEATH,
143 .out.err = -EXDEV, .pass = false },
144 { .name = "[beneath] chained absolute links to $root",
145 .path = "abscheeky/absself", .how.resolve = RESOLVE_BENEATH,
146 .out.err = -EXDEV, .pass = false },
147 { .name = "[beneath] jump outside $root",
148 .path = "..", .how.resolve = RESOLVE_BENEATH,
149 .out.err = -EXDEV, .pass = false },
150 { .name = "[beneath] temporary jump outside $root",
151 .path = "../root/", .how.resolve = RESOLVE_BENEATH,
152 .out.err = -EXDEV, .pass = false },
153 { .name = "[beneath] symlink temporary jump outside $root",
154 .path = "cheeky/self", .how.resolve = RESOLVE_BENEATH,
155 .out.err = -EXDEV, .pass = false },
156 { .name = "[beneath] chained symlink temporary jump outside $root",
157 .path = "abscheeky/self", .how.resolve = RESOLVE_BENEATH,
158 .out.err = -EXDEV, .pass = false },
159 { .name = "[beneath] garbage links to $root",
160 .path = "cheeky/garbageself", .how.resolve = RESOLVE_BENEATH,
161 .out.err = -EXDEV, .pass = false },
162 { .name = "[beneath] chained garbage links to $root",
163 .path = "abscheeky/garbageself", .how.resolve = RESOLVE_BENEATH,
164 .out.err = -EXDEV, .pass = false },
165 /* Only relative paths that stay inside dirfd should work. */
166 { .name = "[beneath] ordinary path to 'root'",
167 .path = "root", .how.resolve = RESOLVE_BENEATH,
168 .out.path = "root", .pass = true },
169 { .name = "[beneath] ordinary path to 'etc'",
170 .path = "etc", .how.resolve = RESOLVE_BENEATH,
171 .out.path = "etc", .pass = true },
172 { .name = "[beneath] ordinary path to 'etc/passwd'",
173 .path = "etc/passwd", .how.resolve = RESOLVE_BENEATH,
174 .out.path = "etc/passwd", .pass = true },
175 { .name = "[beneath] relative symlink inside $root",
176 .path = "relsym", .how.resolve = RESOLVE_BENEATH,
177 .out.path = "etc/passwd", .pass = true },
178 { .name = "[beneath] chained-'..' relative symlink inside $root",
179 .path = "cheeky/passwd", .how.resolve = RESOLVE_BENEATH,
180 .out.path = "etc/passwd", .pass = true },
181 { .name = "[beneath] absolute symlink component outside $root",
182 .path = "abscheeky/passwd", .how.resolve = RESOLVE_BENEATH,
183 .out.err = -EXDEV, .pass = false },
184 { .name = "[beneath] absolute symlink target outside $root",
185 .path = "abssym", .how.resolve = RESOLVE_BENEATH,
186 .out.err = -EXDEV, .pass = false },
187 { .name = "[beneath] absolute path outside $root",
188 .path = "/etc/passwd", .how.resolve = RESOLVE_BENEATH,
189 .out.err = -EXDEV, .pass = false },
190 { .name = "[beneath] cheeky absolute path outside $root",
191 .path = "cheeky/abspasswd", .how.resolve = RESOLVE_BENEATH,
192 .out.err = -EXDEV, .pass = false },
193 { .name = "[beneath] chained cheeky absolute path outside $root",
194 .path = "abscheeky/abspasswd", .how.resolve = RESOLVE_BENEATH,
195 .out.err = -EXDEV, .pass = false },
196 /* Tricky paths should fail. */
197 { .name = "[beneath] tricky '..'-chained symlink outside $root",
198 .path = "cheeky/dotdotlink", .how.resolve = RESOLVE_BENEATH,
199 .out.err = -EXDEV, .pass = false },
200 { .name = "[beneath] tricky absolute + '..'-chained symlink outside $root",
201 .path = "abscheeky/dotdotlink", .how.resolve = RESOLVE_BENEATH,
202 .out.err = -EXDEV, .pass = false },
203 { .name = "[beneath] tricky garbage link outside $root",
204 .path = "cheeky/garbagelink", .how.resolve = RESOLVE_BENEATH,
205 .out.err = -EXDEV, .pass = false },
206 { .name = "[beneath] tricky absolute + garbage link outside $root",
207 .path = "abscheeky/garbagelink", .how.resolve = RESOLVE_BENEATH,
208 .out.err = -EXDEV, .pass = false },
209
210 /** RESOLVE_IN_ROOT **/
211 /* All attempts to cross the dirfd will be scoped-to-root. */
212 { .name = "[in_root] jump to /",
213 .path = "/", .how.resolve = RESOLVE_IN_ROOT,
214 .out.path = NULL, .pass = true },
215 { .name = "[in_root] absolute symlink to /root",
216 .path = "cheeky/absself", .how.resolve = RESOLVE_IN_ROOT,
217 .out.path = NULL, .pass = true },
218 { .name = "[in_root] chained absolute symlinks to /root",
219 .path = "abscheeky/absself", .how.resolve = RESOLVE_IN_ROOT,
220 .out.path = NULL, .pass = true },
221 { .name = "[in_root] '..' at root",
222 .path = "..", .how.resolve = RESOLVE_IN_ROOT,
223 .out.path = NULL, .pass = true },
224 { .name = "[in_root] '../root' at root",
225 .path = "../root/", .how.resolve = RESOLVE_IN_ROOT,
226 .out.path = "root", .pass = true },
227 { .name = "[in_root] relative symlink containing '..' above root",
228 .path = "cheeky/self", .how.resolve = RESOLVE_IN_ROOT,
229 .out.path = "root", .pass = true },
230 { .name = "[in_root] garbage link to /root",
231 .path = "cheeky/garbageself", .how.resolve = RESOLVE_IN_ROOT,
232 .out.path = "root", .pass = true },
233 { .name = "[in_root] chained garbage links to /root",
234 .path = "abscheeky/garbageself", .how.resolve = RESOLVE_IN_ROOT,
235 .out.path = "root", .pass = true },
236 { .name = "[in_root] relative path to 'root'",
237 .path = "root", .how.resolve = RESOLVE_IN_ROOT,
238 .out.path = "root", .pass = true },
239 { .name = "[in_root] relative path to 'etc'",
240 .path = "etc", .how.resolve = RESOLVE_IN_ROOT,
241 .out.path = "etc", .pass = true },
242 { .name = "[in_root] relative path to 'etc/passwd'",
243 .path = "etc/passwd", .how.resolve = RESOLVE_IN_ROOT,
244 .out.path = "etc/passwd", .pass = true },
245 { .name = "[in_root] relative symlink to 'etc/passwd'",
246 .path = "relsym", .how.resolve = RESOLVE_IN_ROOT,
247 .out.path = "etc/passwd", .pass = true },
248 { .name = "[in_root] chained-'..' relative symlink to 'etc/passwd'",
249 .path = "cheeky/passwd", .how.resolve = RESOLVE_IN_ROOT,
250 .out.path = "etc/passwd", .pass = true },
251 { .name = "[in_root] chained-'..' absolute + relative symlink to 'etc/passwd'",
252 .path = "abscheeky/passwd", .how.resolve = RESOLVE_IN_ROOT,
253 .out.path = "etc/passwd", .pass = true },
254 { .name = "[in_root] absolute symlink to 'etc/passwd'",
255 .path = "abssym", .how.resolve = RESOLVE_IN_ROOT,
256 .out.path = "etc/passwd", .pass = true },
257 { .name = "[in_root] absolute path 'etc/passwd'",
258 .path = "/etc/passwd", .how.resolve = RESOLVE_IN_ROOT,
259 .out.path = "etc/passwd", .pass = true },
260 { .name = "[in_root] cheeky absolute path 'etc/passwd'",
261 .path = "cheeky/abspasswd", .how.resolve = RESOLVE_IN_ROOT,
262 .out.path = "etc/passwd", .pass = true },
263 { .name = "[in_root] chained cheeky absolute path 'etc/passwd'",
264 .path = "abscheeky/abspasswd", .how.resolve = RESOLVE_IN_ROOT,
265 .out.path = "etc/passwd", .pass = true },
266 { .name = "[in_root] tricky '..'-chained symlink outside $root",
267 .path = "cheeky/dotdotlink", .how.resolve = RESOLVE_IN_ROOT,
268 .out.path = "etc/passwd", .pass = true },
269 { .name = "[in_root] tricky absolute + '..'-chained symlink outside $root",
270 .path = "abscheeky/dotdotlink", .how.resolve = RESOLVE_IN_ROOT,
271 .out.path = "etc/passwd", .pass = true },
272 { .name = "[in_root] tricky absolute path + absolute + '..'-chained symlink outside $root",
273 .path = "/../../../../abscheeky/dotdotlink", .how.resolve = RESOLVE_IN_ROOT,
274 .out.path = "etc/passwd", .pass = true },
275 { .name = "[in_root] tricky garbage link outside $root",
276 .path = "cheeky/garbagelink", .how.resolve = RESOLVE_IN_ROOT,
277 .out.path = "etc/passwd", .pass = true },
278 { .name = "[in_root] tricky absolute + garbage link outside $root",
279 .path = "abscheeky/garbagelink", .how.resolve = RESOLVE_IN_ROOT,
280 .out.path = "etc/passwd", .pass = true },
281 { .name = "[in_root] tricky absolute path + absolute + garbage link outside $root",
282 .path = "/../../../../abscheeky/garbagelink", .how.resolve = RESOLVE_IN_ROOT,
283 .out.path = "etc/passwd", .pass = true },
284 /* O_CREAT should handle trailing symlinks correctly. */
285 { .name = "[in_root] O_CREAT of relative path inside $root",
286 .path = "newfile1", .how.flags = O_CREAT,
287 .how.mode = 0700,
288 .how.resolve = RESOLVE_IN_ROOT,
289 .out.path = "newfile1", .pass = true },
290 { .name = "[in_root] O_CREAT of absolute path",
291 .path = "/newfile2", .how.flags = O_CREAT,
292 .how.mode = 0700,
293 .how.resolve = RESOLVE_IN_ROOT,
294 .out.path = "newfile2", .pass = true },
295 { .name = "[in_root] O_CREAT of tricky symlink outside root",
296 .path = "/creatlink", .how.flags = O_CREAT,
297 .how.mode = 0700,
298 .how.resolve = RESOLVE_IN_ROOT,
299 .out.path = "newfile3", .pass = true },
300
301 /** RESOLVE_NO_XDEV **/
302 /* Crossing *down* into a mountpoint is disallowed. */
303 { .name = "[no_xdev] cross into $mnt",
304 .path = "mnt", .how.resolve = RESOLVE_NO_XDEV,
305 .out.err = -EXDEV, .pass = false },
306 { .name = "[no_xdev] cross into $mnt/",
307 .path = "mnt/", .how.resolve = RESOLVE_NO_XDEV,
308 .out.err = -EXDEV, .pass = false },
309 { .name = "[no_xdev] cross into $mnt/.",
310 .path = "mnt/.", .how.resolve = RESOLVE_NO_XDEV,
311 .out.err = -EXDEV, .pass = false },
312 /* Crossing *up* out of a mountpoint is disallowed. */
313 { .name = "[no_xdev] goto mountpoint root",
314 .dir = "mnt", .path = ".", .how.resolve = RESOLVE_NO_XDEV,
315 .out.path = "mnt", .pass = true },
316 { .name = "[no_xdev] cross up through '..'",
317 .dir = "mnt", .path = "..", .how.resolve = RESOLVE_NO_XDEV,
318 .out.err = -EXDEV, .pass = false },
319 { .name = "[no_xdev] temporary cross up through '..'",
320 .dir = "mnt", .path = "../mnt", .how.resolve = RESOLVE_NO_XDEV,
321 .out.err = -EXDEV, .pass = false },
322 { .name = "[no_xdev] temporary relative symlink cross up",
323 .dir = "mnt", .path = "self", .how.resolve = RESOLVE_NO_XDEV,
324 .out.err = -EXDEV, .pass = false },
325 { .name = "[no_xdev] temporary absolute symlink cross up",
326 .dir = "mnt", .path = "absself", .how.resolve = RESOLVE_NO_XDEV,
327 .out.err = -EXDEV, .pass = false },
328 /* Jumping to "/" is ok, but later components cannot cross. */
329 { .name = "[no_xdev] jump to / directly",
330 .dir = "mnt", .path = "/", .how.resolve = RESOLVE_NO_XDEV,
331 .out.path = "/", .pass = true },
332 { .name = "[no_xdev] jump to / (from /) directly",
333 .dir = "/", .path = "/", .how.resolve = RESOLVE_NO_XDEV,
334 .out.path = "/", .pass = true },
335 { .name = "[no_xdev] jump to / then proc",
336 .path = "/proc/1", .how.resolve = RESOLVE_NO_XDEV,
337 .out.err = -EXDEV, .pass = false },
338 { .name = "[no_xdev] jump to / then tmp",
339 .path = "/tmp", .how.resolve = RESOLVE_NO_XDEV,
340 .out.err = -EXDEV, .pass = false },
341 /* Magic-links are blocked since they can switch vfsmounts. */
342 { .name = "[no_xdev] cross through magic-link to self/root",
343 .dir = "/proc", .path = "self/root", .how.resolve = RESOLVE_NO_XDEV,
344 .out.err = -EXDEV, .pass = false },
345 { .name = "[no_xdev] cross through magic-link to self/cwd",
346 .dir = "/proc", .path = "self/cwd", .how.resolve = RESOLVE_NO_XDEV,
347 .out.err = -EXDEV, .pass = false },
348 /* Except magic-link jumps inside the same vfsmount. */
349 { .name = "[no_xdev] jump through magic-link to same procfs",
350 .dir = "/proc", .path = hardcoded_fdpath, .how.resolve = RESOLVE_NO_XDEV,
351 .out.path = "/proc", .pass = true, },
352
353 /** RESOLVE_NO_MAGICLINKS **/
354 /* Regular symlinks should work. */
355 { .name = "[no_magiclinks] ordinary relative symlink",
356 .path = "relsym", .how.resolve = RESOLVE_NO_MAGICLINKS,
357 .out.path = "etc/passwd", .pass = true },
358 /* Magic-links should not work. */
359 { .name = "[no_magiclinks] symlink to magic-link",
360 .path = "procexe", .how.resolve = RESOLVE_NO_MAGICLINKS,
361 .out.err = -ELOOP, .pass = false },
362 { .name = "[no_magiclinks] normal path to magic-link",
363 .path = "/proc/self/exe", .how.resolve = RESOLVE_NO_MAGICLINKS,
364 .out.err = -ELOOP, .pass = false },
365 { .name = "[no_magiclinks] normal path to magic-link with O_NOFOLLOW",
366 .path = "/proc/self/exe", .how.flags = O_NOFOLLOW,
367 .how.resolve = RESOLVE_NO_MAGICLINKS,
368 .out.path = procselfexe, .pass = true },
369 { .name = "[no_magiclinks] symlink to magic-link path component",
370 .path = "procroot/etc", .how.resolve = RESOLVE_NO_MAGICLINKS,
371 .out.err = -ELOOP, .pass = false },
372 { .name = "[no_magiclinks] magic-link path component",
373 .path = "/proc/self/root/etc", .how.resolve = RESOLVE_NO_MAGICLINKS,
374 .out.err = -ELOOP, .pass = false },
375 { .name = "[no_magiclinks] magic-link path component with O_NOFOLLOW",
376 .path = "/proc/self/root/etc", .how.flags = O_NOFOLLOW,
377 .how.resolve = RESOLVE_NO_MAGICLINKS,
378 .out.err = -ELOOP, .pass = false },
379
380 /** RESOLVE_NO_SYMLINKS **/
381 /* Normal paths should work. */
382 { .name = "[no_symlinks] ordinary path to '.'",
383 .path = ".", .how.resolve = RESOLVE_NO_SYMLINKS,
384 .out.path = NULL, .pass = true },
385 { .name = "[no_symlinks] ordinary path to 'root'",
386 .path = "root", .how.resolve = RESOLVE_NO_SYMLINKS,
387 .out.path = "root", .pass = true },
388 { .name = "[no_symlinks] ordinary path to 'etc'",
389 .path = "etc", .how.resolve = RESOLVE_NO_SYMLINKS,
390 .out.path = "etc", .pass = true },
391 { .name = "[no_symlinks] ordinary path to 'etc/passwd'",
392 .path = "etc/passwd", .how.resolve = RESOLVE_NO_SYMLINKS,
393 .out.path = "etc/passwd", .pass = true },
394 /* Regular symlinks are blocked. */
395 { .name = "[no_symlinks] relative symlink target",
396 .path = "relsym", .how.resolve = RESOLVE_NO_SYMLINKS,
397 .out.err = -ELOOP, .pass = false },
398 { .name = "[no_symlinks] relative symlink component",
399 .path = "reletc/passwd", .how.resolve = RESOLVE_NO_SYMLINKS,
400 .out.err = -ELOOP, .pass = false },
401 { .name = "[no_symlinks] absolute symlink target",
402 .path = "abssym", .how.resolve = RESOLVE_NO_SYMLINKS,
403 .out.err = -ELOOP, .pass = false },
404 { .name = "[no_symlinks] absolute symlink component",
405 .path = "absetc/passwd", .how.resolve = RESOLVE_NO_SYMLINKS,
406 .out.err = -ELOOP, .pass = false },
407 { .name = "[no_symlinks] cheeky garbage link",
408 .path = "cheeky/garbagelink", .how.resolve = RESOLVE_NO_SYMLINKS,
409 .out.err = -ELOOP, .pass = false },
410 { .name = "[no_symlinks] cheeky absolute + garbage link",
411 .path = "abscheeky/garbagelink", .how.resolve = RESOLVE_NO_SYMLINKS,
412 .out.err = -ELOOP, .pass = false },
413 { .name = "[no_symlinks] cheeky absolute + absolute symlink",
414 .path = "abscheeky/absself", .how.resolve = RESOLVE_NO_SYMLINKS,
415 .out.err = -ELOOP, .pass = false },
416 /* Trailing symlinks with NO_FOLLOW. */
417 { .name = "[no_symlinks] relative symlink with O_NOFOLLOW",
418 .path = "relsym", .how.flags = O_NOFOLLOW,
419 .how.resolve = RESOLVE_NO_SYMLINKS,
420 .out.path = "relsym", .pass = true },
421 { .name = "[no_symlinks] absolute symlink with O_NOFOLLOW",
422 .path = "abssym", .how.flags = O_NOFOLLOW,
423 .how.resolve = RESOLVE_NO_SYMLINKS,
424 .out.path = "abssym", .pass = true },
425 { .name = "[no_symlinks] trailing symlink with O_NOFOLLOW",
426 .path = "cheeky/garbagelink", .how.flags = O_NOFOLLOW,
427 .how.resolve = RESOLVE_NO_SYMLINKS,
428 .out.path = "cheeky/garbagelink", .pass = true },
429 { .name = "[no_symlinks] multiple symlink components with O_NOFOLLOW",
430 .path = "abscheeky/absself", .how.flags = O_NOFOLLOW,
431 .how.resolve = RESOLVE_NO_SYMLINKS,
432 .out.err = -ELOOP, .pass = false },
433 { .name = "[no_symlinks] multiple symlink (and garbage link) components with O_NOFOLLOW",
434 .path = "abscheeky/garbagelink", .how.flags = O_NOFOLLOW,
435 .how.resolve = RESOLVE_NO_SYMLINKS,
436 .out.err = -ELOOP, .pass = false },
437 };
438
439 BUILD_BUG_ON(ARRAY_LEN(tests) != NUM_OPENAT2_OPATH_TESTS);
440
441 for (int i = 0; i < ARRAY_LEN(tests); i++) {
442 int dfd, fd;
443 char *fdpath = NULL;
444 bool failed;
445 void (*resultfn)(const char *msg, ...) = ksft_test_result_pass;
446 struct basic_test *test = &tests[i];
447
448 if (!openat2_supported) {
449 ksft_print_msg("openat2(2) unsupported\n");
450 resultfn = ksft_test_result_skip;
451 goto skip;
452 }
453
454 /* Auto-set O_PATH. */
455 if (!(test->how.flags & O_CREAT))
456 test->how.flags |= O_PATH;
457
458 if (test->dir)
459 dfd = openat(rootfd, test->dir, O_PATH | O_DIRECTORY);
460 else
461 dfd = dup(rootfd);
462 E_assert(dfd, "failed to openat root '%s': %m", test->dir);
463
464 E_dup2(dfd, hardcoded_fd);
465
466 fd = sys_openat2(dfd, test->path, &test->how);
467 if (test->pass)
468 failed = (fd < 0 || !fdequal(fd, rootfd, test->out.path));
469 else
470 failed = (fd != test->out.err);
471 if (fd >= 0) {
472 fdpath = fdreadlink(fd);
473 close(fd);
474 }
475 close(dfd);
476
477 if (failed) {
478 resultfn = ksft_test_result_fail;
479
480 ksft_print_msg("openat2 unexpectedly returned ");
481 if (fdpath)
482 ksft_print_msg("%d['%s']\n", fd, fdpath);
483 else
484 ksft_print_msg("%d (%s)\n", fd, strerror(-fd));
485 }
486
487skip:
488 if (test->pass)
489 resultfn("%s gives path '%s'\n", test->name,
490 test->out.path ?: ".");
491 else
492 resultfn("%s fails with %d (%s)\n", test->name,
493 test->out.err, strerror(-test->out.err));
494
495 fflush(stdout);
496 free(fdpath);
497 }
498
499 free(procselfexe);
500 close(rootfd);
501
502 free(hardcoded_fdpath);
503 close(hardcoded_fd);
504}
505
506#define NUM_TESTS NUM_OPENAT2_OPATH_TESTS
507
508int main(int argc, char **argv)
509{
510 ksft_print_header();
511 ksft_set_plan(NUM_TESTS);
512
513 /* NOTE: We should be checking for CAP_SYS_ADMIN here... */
514 if (geteuid() != 0)
515 ksft_exit_skip(msg: "all tests require euid == 0\n");
516
517 test_openat2_opath_tests();
518
519 if (ksft_get_fail_cnt() + ksft_get_error_cnt() > 0)
520 ksft_exit_fail();
521 else
522 ksft_exit_pass();
523}
524

source code of linux/tools/testing/selftests/openat2/resolve_test.c