xref: /aosp_15_r20/external/ltp/testcases/kernel/syscalls/fanotify/fanotify01.c (revision 49cdfc7efb34551c7342be41a7384b9c40d7cab7)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (c) 2013 SUSE.  All Rights Reserved.
4  *
5  * Started by Jan Kara <[email protected]>
6  */
7 
8 /*\
9  * [Description]
10  * Check that fanotify work for a file.
11  */
12 
13 #define _GNU_SOURCE
14 #include "config.h"
15 
16 #include <stdio.h>
17 #include <sys/stat.h>
18 #include <sys/types.h>
19 #include <errno.h>
20 #include <string.h>
21 #include <sys/syscall.h>
22 #include "tst_test.h"
23 
24 #ifdef HAVE_SYS_FANOTIFY_H
25 #include "fanotify.h"
26 
27 #define EVENT_MAX 1024
28 /* size of the event structure, not counting name */
29 #define EVENT_SIZE  (sizeof(struct fanotify_event_metadata))
30 /* reasonable guess as to size of 1024 events */
31 #define EVENT_BUF_LEN        (EVENT_MAX * EVENT_SIZE)
32 
33 #define BUF_SIZE 256
34 #define TST_TOTAL 12
35 
36 #define MOUNT_PATH "fs_mnt"
37 
38 static struct tcase {
39 	const char *tname;
40 	struct fanotify_mark_type mark;
41 	unsigned int init_flags;
42 } tcases[] = {
43 	{
44 		"inode mark events",
45 		INIT_FANOTIFY_MARK_TYPE(INODE),
46 		FAN_CLASS_NOTIF
47 	},
48 	{
49 		"mount mark events",
50 		INIT_FANOTIFY_MARK_TYPE(MOUNT),
51 		FAN_CLASS_NOTIF
52 	},
53 	{
54 		"filesystem mark events",
55 		INIT_FANOTIFY_MARK_TYPE(FILESYSTEM),
56 		FAN_CLASS_NOTIF
57 	},
58 	{
59 		"inode mark events (FAN_REPORT_FID)",
60 		INIT_FANOTIFY_MARK_TYPE(INODE),
61 		FAN_CLASS_NOTIF|FAN_REPORT_FID
62 	},
63 	{
64 		"mount mark events (FAN_REPORT_FID)",
65 		INIT_FANOTIFY_MARK_TYPE(MOUNT),
66 		FAN_CLASS_NOTIF|FAN_REPORT_FID
67 	},
68 	{
69 		"filesystem mark events (FAN_REPORT_FID)",
70 		INIT_FANOTIFY_MARK_TYPE(FILESYSTEM),
71 		FAN_CLASS_NOTIF|FAN_REPORT_FID
72 	},
73 };
74 
75 static char fname[BUF_SIZE];
76 static char buf[BUF_SIZE];
77 static int fd_notify;
78 static int fan_report_fid_unsupported;
79 static int mount_mark_fid_unsupported;
80 static int inode_mark_fid_xdev;
81 static int filesystem_mark_unsupported;
82 
83 static unsigned long long event_set[EVENT_MAX];
84 
85 static char event_buf[EVENT_BUF_LEN];
86 
test_fanotify(unsigned int n)87 static void test_fanotify(unsigned int n)
88 {
89 	struct tcase *tc = &tcases[n];
90 	struct fanotify_mark_type *mark = &tc->mark;
91 	int fd, ret, len, i = 0, test_num = 0;
92 	int tst_count = 0;
93 	int report_fid = (tc->init_flags & FAN_REPORT_FID);
94 
95 	tst_res(TINFO, "Test #%d: %s", n, tc->tname);
96 
97 	if (fan_report_fid_unsupported && report_fid) {
98 		FANOTIFY_INIT_FLAGS_ERR_MSG(FAN_REPORT_FID, fan_report_fid_unsupported);
99 		return;
100 	}
101 
102 	if (filesystem_mark_unsupported && mark->flag == FAN_MARK_FILESYSTEM) {
103 		FANOTIFY_MARK_FLAGS_ERR_MSG(mark, filesystem_mark_unsupported);
104 		return;
105 	}
106 
107 	if (mount_mark_fid_unsupported && report_fid && mark->flag != FAN_MARK_INODE) {
108 		FANOTIFY_MARK_FLAGS_ERR_MSG(mark, mount_mark_fid_unsupported);
109 		return;
110 	}
111 
112 	fd_notify = SAFE_FANOTIFY_INIT(tc->init_flags, O_RDONLY);
113 
114 	SAFE_FANOTIFY_MARK(fd_notify, FAN_MARK_ADD | mark->flag,
115 			  FAN_ACCESS | FAN_MODIFY | FAN_CLOSE | FAN_OPEN, AT_FDCWD, fname);
116 
117 	/*
118 	 * generate sequence of events
119 	 */
120 	fd = SAFE_OPEN(fname, O_RDONLY);
121 	event_set[tst_count] = FAN_OPEN;
122 	tst_count++;
123 
124 	SAFE_READ(0, fd, buf, BUF_SIZE);
125 	event_set[tst_count] = FAN_ACCESS;
126 	tst_count++;
127 
128 	SAFE_CLOSE(fd);
129 	event_set[tst_count] = FAN_CLOSE_NOWRITE;
130 	tst_count++;
131 
132 	/*
133 	 * Get list of events so far. We get events here to avoid
134 	 * merging of following events with the previous ones.
135 	 */
136 	ret = SAFE_READ(0, fd_notify, event_buf, EVENT_BUF_LEN);
137 	len = ret;
138 
139 	fd = SAFE_OPEN(fname, O_RDWR | O_CREAT, 0700);
140 	event_set[tst_count] = FAN_OPEN;
141 	tst_count++;
142 
143 	SAFE_WRITE(SAFE_WRITE_ALL, fd, fname, strlen(fname));
144 	event_set[tst_count] = FAN_MODIFY;
145 	tst_count++;
146 
147 	SAFE_CLOSE(fd);
148 	event_set[tst_count] = FAN_CLOSE_WRITE;
149 	tst_count++;
150 
151 	/*
152 	 * get another list of events
153 	 */
154 	ret = SAFE_READ(0, fd_notify, event_buf + len,
155 			EVENT_BUF_LEN - len);
156 	len += ret;
157 
158 	/*
159 	 * Ignore mask testing
160 	 */
161 
162 	/* Ignore access events */
163 	SAFE_FANOTIFY_MARK(fd_notify,
164 			  FAN_MARK_ADD | mark->flag | FAN_MARK_IGNORED_MASK,
165 			  FAN_ACCESS, AT_FDCWD, fname);
166 
167 	fd = SAFE_OPEN(fname, O_RDWR);
168 	event_set[tst_count] = FAN_OPEN;
169 	tst_count++;
170 
171 	/* This event should be ignored */
172 	SAFE_READ(0, fd, buf, BUF_SIZE);
173 
174 	/*
175 	 * get another list of events to verify the last one got ignored
176 	 */
177 	ret = SAFE_READ(0, fd_notify, event_buf + len,
178 			EVENT_BUF_LEN - len);
179 	len += ret;
180 
181 	SAFE_LSEEK(fd, 0, SEEK_SET);
182 	/* Generate modify event to clear ignore mask */
183 	SAFE_WRITE(SAFE_WRITE_ALL, fd, fname, 1);
184 	event_set[tst_count] = FAN_MODIFY;
185 	tst_count++;
186 
187 	/*
188 	 * This event shouldn't be ignored because previous modification
189 	 * should have removed the ignore mask
190 	 */
191 	SAFE_READ(0, fd, buf, BUF_SIZE);
192 	event_set[tst_count] = FAN_ACCESS;
193 	tst_count++;
194 
195 	SAFE_CLOSE(fd);
196 	event_set[tst_count] = FAN_CLOSE_WRITE;
197 	tst_count++;
198 
199 	/* Read events to verify previous access was properly generated */
200 	ret = SAFE_READ(0, fd_notify, event_buf + len,
201 			EVENT_BUF_LEN - len);
202 	len += ret;
203 
204 	/*
205 	 * Now ignore open & close events regardless of file
206 	 * modifications
207 	 */
208 	SAFE_FANOTIFY_MARK(fd_notify, FAN_MARK_ADD | mark->flag |
209 			  FAN_MARK_IGNORED_MASK | FAN_MARK_IGNORED_SURV_MODIFY,
210 			  FAN_OPEN | FAN_CLOSE, AT_FDCWD, fname);
211 
212 	/* This event should be ignored */
213 	fd = SAFE_OPEN(fname, O_RDWR);
214 
215 	SAFE_WRITE(SAFE_WRITE_ALL, fd, fname, 1);
216 	event_set[tst_count] = FAN_MODIFY;
217 	tst_count++;
218 
219 	/* This event should be still ignored */
220 	SAFE_CLOSE(fd);
221 
222 	/* This event should still be ignored */
223 	fd = SAFE_OPEN(fname, O_RDWR);
224 
225 	/* Read events to verify open & close were ignored */
226 	ret = SAFE_READ(0, fd_notify, event_buf + len,
227 			EVENT_BUF_LEN - len);
228 	len += ret;
229 
230 	/* Now remove open and close from ignored mask */
231 	SAFE_FANOTIFY_MARK(fd_notify,
232 			  FAN_MARK_REMOVE | mark->flag | FAN_MARK_IGNORED_MASK,
233 			  FAN_OPEN | FAN_CLOSE, AT_FDCWD, fname);
234 
235 	SAFE_CLOSE(fd);
236 	event_set[tst_count] = FAN_CLOSE_WRITE;
237 	tst_count++;
238 
239 	/* Read events to verify close was generated */
240 	ret = SAFE_READ(0, fd_notify, event_buf + len,
241 			EVENT_BUF_LEN - len);
242 	len += ret;
243 
244 	if (TST_TOTAL != tst_count) {
245 		tst_brk(TBROK,
246 			"TST_TOTAL (%d) and tst_count (%d) are not "
247 			"equal", TST_TOTAL, tst_count);
248 	}
249 	tst_count = 0;
250 
251 	/*
252 	 * check events
253 	 */
254 	while (i < len) {
255 		struct fanotify_event_metadata *event;
256 
257 		event = (struct fanotify_event_metadata *)&event_buf[i];
258 		if (test_num >= TST_TOTAL) {
259 			tst_res(TFAIL,
260 				"got unnecessary event: mask=%llx "
261 				"pid=%u fd=%d",
262 				(unsigned long long)event->mask,
263 				(unsigned int)event->pid, event->fd);
264 		} else if (!(event->mask & event_set[test_num])) {
265 			tst_res(TFAIL,
266 				"got event: mask=%llx (expected %llx) "
267 				"pid=%u fd=%d",
268 				(unsigned long long)event->mask,
269 				event_set[test_num],
270 				(unsigned int)event->pid, event->fd);
271 		} else if (event->pid != getpid()) {
272 			tst_res(TFAIL,
273 				"got event: mask=%llx pid=%u "
274 				"(expected %u) fd=%d",
275 				(unsigned long long)event->mask,
276 				(unsigned int)event->pid,
277 				(unsigned int)getpid(),
278 				event->fd);
279 		} else {
280 			if (event->fd == -2 || (event->fd == FAN_NOFD &&
281 			    (tc->init_flags & FAN_REPORT_FID)))
282 				goto pass;
283 			ret = read(event->fd, buf, BUF_SIZE);
284 			if (ret != (int)strlen(fname)) {
285 				tst_res(TFAIL,
286 					"cannot read from returned fd "
287 					"of event: mask=%llx pid=%u "
288 					"fd=%d ret=%d (errno=%d)",
289 					(unsigned long long)event->mask,
290 					(unsigned int)event->pid,
291 					event->fd, ret, errno);
292 			} else if (memcmp(buf, fname, strlen(fname))) {
293 				tst_res(TFAIL,
294 					"wrong data read from returned fd "
295 					"of event: mask=%llx pid=%u "
296 					"fd=%d",
297 					(unsigned long long)event->mask,
298 					(unsigned int)event->pid,
299 					event->fd);
300 			} else {
301 pass:
302 				tst_res(TPASS,
303 					"got event: mask=%llx pid=%u fd=%d",
304 					(unsigned long long)event->mask,
305 					(unsigned int)event->pid, event->fd);
306 			}
307 		}
308 
309 		/*
310 		 * We have verified the data now so close fd and
311 		 * invalidate it so that we don't check it again
312 		 * unnecessarily
313 		 */
314 		if (event->fd >= 0)
315 			SAFE_CLOSE(event->fd);
316 		event->fd = -2;
317 		event->mask &= ~event_set[test_num];
318 
319 		/* No events left in current mask? Go for next event */
320 		if (event->mask == 0)
321 			i += event->event_len;
322 
323 		test_num++;
324 	}
325 
326 	for (; test_num < TST_TOTAL; test_num++) {
327 		tst_res(TFAIL, "didn't get event: mask=%llx",
328 			event_set[test_num]);
329 
330 	}
331 
332 
333 	/*
334 	 * Try to setup a bogus mark on test tmp dir, to check if marks on
335 	 * different filesystems are supported.
336 	 * When tested fs has zero fsid (e.g. fuse) and events are reported
337 	 * with fsid+fid, watching different filesystems is not supported.
338 	 */
339 	ret = report_fid ? inode_mark_fid_xdev : 0;
340 	TST_EXP_FD_OR_FAIL(fanotify_mark(fd_notify, FAN_MARK_ADD, FAN_CLOSE_WRITE,
341 					 AT_FDCWD, "."), ret);
342 
343 	/* Remove mark to clear FAN_MARK_IGNORED_SURV_MODIFY */
344 	SAFE_FANOTIFY_MARK(fd_notify, FAN_MARK_REMOVE | mark->flag,
345 			  FAN_ACCESS | FAN_MODIFY | FAN_CLOSE | FAN_OPEN,
346 			  AT_FDCWD, fname);
347 
348 	SAFE_CLOSE(fd_notify);
349 }
350 
setup(void)351 static void setup(void)
352 {
353 	int fd;
354 
355 	/* Check for kernel fanotify support */
356 	fd = SAFE_FANOTIFY_INIT(FAN_CLASS_NOTIF, O_RDONLY);
357 	SAFE_CLOSE(fd);
358 
359 	sprintf(fname, MOUNT_PATH"/tfile_%d", getpid());
360 	SAFE_FILE_PRINTF(fname, "1");
361 
362 	fan_report_fid_unsupported = fanotify_init_flags_supported_on_fs(FAN_REPORT_FID, fname);
363 	filesystem_mark_unsupported = fanotify_mark_supported_on_fs(FAN_MARK_FILESYSTEM, fname);
364 	mount_mark_fid_unsupported = fanotify_flags_supported_on_fs(FAN_REPORT_FID,
365 								    FAN_MARK_MOUNT,
366 								    FAN_OPEN, fname);
367 	/*
368 	 * When mount mark is not supported due to zero fsid (e.g. fuse) or if TMPDIR has
369 	 * non-uniform fsid (e.g. btrfs subvol), multi fs inode marks are not supported.
370 	 */
371 	if (mount_mark_fid_unsupported && errno == ENODEV) {
372 		tst_res(TINFO, "filesystem %s does not support reporting events with fid from multi fs",
373 				tst_device->fs_type);
374 		inode_mark_fid_xdev = EXDEV;
375 	}
376 
377 	if (fanotify_flags_supported_on_fs(FAN_REPORT_FID, FAN_MARK_MOUNT, FAN_OPEN, ".")) {
378 		inode_mark_fid_xdev = errno;
379 		tst_res(TINFO, "TMPDIR does not support reporting events with fid from multi fs");
380 	}
381 }
382 
cleanup(void)383 static void cleanup(void)
384 {
385 	if (fd_notify > 0)
386 		SAFE_CLOSE(fd_notify);
387 }
388 
389 static struct tst_test test = {
390 	.test = test_fanotify,
391 	.tcnt = ARRAY_SIZE(tcases),
392 	.setup = setup,
393 	.cleanup = cleanup,
394 	.needs_root = 1,
395 	.mount_device = 1,
396 	.mntpoint = MOUNT_PATH,
397 	.all_filesystems = 1,
398 };
399 
400 #else
401 	TST_TEST_TCONF("system doesn't have required fanotify support");
402 #endif
403