1// SPDX-License-Identifier: GPL-2.0
2/*
3 * User Events FTrace Test Program
4 *
5 * Copyright (c) 2021 Beau Belgrave <beaub@linux.microsoft.com>
6 */
7
8#include <errno.h>
9#include <linux/user_events.h>
10#include <stdio.h>
11#include <stdlib.h>
12#include <fcntl.h>
13#include <sys/ioctl.h>
14#include <sys/stat.h>
15#include <sys/uio.h>
16#include <unistd.h>
17
18#include "../kselftest_harness.h"
19#include "user_events_selftests.h"
20
21const char *data_file = "/sys/kernel/tracing/user_events_data";
22const char *status_file = "/sys/kernel/tracing/user_events_status";
23const char *enable_file = "/sys/kernel/tracing/events/user_events/__test_event/enable";
24const char *trace_file = "/sys/kernel/tracing/trace";
25const char *fmt_file = "/sys/kernel/tracing/events/user_events/__test_event/format";
26
27static int trace_bytes(void)
28{
29	int fd = open(trace_file, O_RDONLY);
30	char buf[256];
31	int bytes = 0, got;
32
33	if (fd == -1)
34		return -1;
35
36	while (true) {
37		got = read(fd, buf, sizeof(buf));
38
39		if (got == -1)
40			return -1;
41
42		if (got == 0)
43			break;
44
45		bytes += got;
46	}
47
48	close(fd);
49
50	return bytes;
51}
52
53static int skip_until_empty_line(FILE *fp)
54{
55	int c, last = 0;
56
57	while (true) {
58		c = getc(fp);
59
60		if (c == EOF)
61			break;
62
63		if (last == '\n' && c == '\n')
64			return 0;
65
66		last = c;
67	}
68
69	return -1;
70}
71
72static int get_print_fmt(char *buffer, int len)
73{
74	FILE *fp = fopen(fmt_file, "r");
75	char *newline;
76
77	if (!fp)
78		return -1;
79
80	/* Read until empty line (Skip Common) */
81	if (skip_until_empty_line(fp) < 0)
82		goto err;
83
84	/* Read until empty line (Skip Properties) */
85	if (skip_until_empty_line(fp) < 0)
86		goto err;
87
88	/* Read in print_fmt: */
89	if (fgets(buffer, len, fp) == NULL)
90		goto err;
91
92	newline = strchr(buffer, '\n');
93
94	if (newline)
95		*newline = '\0';
96
97	fclose(fp);
98
99	return 0;
100err:
101	fclose(fp);
102
103	return -1;
104}
105
106static bool wait_for_delete(void)
107{
108	int i;
109
110	for (i = 0; i < 1000; ++i) {
111		int fd = open(enable_file, O_RDONLY);
112
113		if (fd == -1)
114			return true;
115
116		close(fd);
117		usleep(1000);
118	}
119
120	return false;
121}
122
123static int clear(int *check)
124{
125	struct user_unreg unreg = {0};
126	int fd;
127
128	unreg.size = sizeof(unreg);
129	unreg.disable_bit = 31;
130	unreg.disable_addr = (__u64)check;
131
132	fd = open(data_file, O_RDWR);
133
134	if (fd == -1)
135		return -1;
136
137	if (ioctl(fd, DIAG_IOCSUNREG, &unreg) == -1)
138		if (errno != ENOENT)
139			goto fail;
140
141	if (ioctl(fd, DIAG_IOCSDEL, "__test_event") == -1) {
142		if (errno == EBUSY) {
143			if (!wait_for_delete())
144				goto fail;
145		} else if (errno != ENOENT)
146			goto fail;
147	}
148
149	close(fd);
150
151	return 0;
152fail:
153	close(fd);
154
155	return -1;
156}
157
158static int check_print_fmt(const char *event, const char *expected, int *check)
159{
160	struct user_reg reg = {0};
161	char print_fmt[256];
162	int ret;
163	int fd;
164
165	/* Ensure cleared */
166	ret = clear(check);
167
168	if (ret != 0)
169		return ret;
170
171	fd = open(data_file, O_RDWR);
172
173	if (fd == -1)
174		return fd;
175
176	reg.size = sizeof(reg);
177	reg.name_args = (__u64)event;
178	reg.enable_bit = 31;
179	reg.enable_addr = (__u64)check;
180	reg.enable_size = sizeof(*check);
181
182	/* Register should work */
183	ret = ioctl(fd, DIAG_IOCSREG, &reg);
184
185	if (ret != 0) {
186		close(fd);
187		printf("Reg failed in fmt\n");
188		return ret;
189	}
190
191	/* Ensure correct print_fmt */
192	ret = get_print_fmt(print_fmt, sizeof(print_fmt));
193
194	close(fd);
195
196	if (ret != 0)
197		return ret;
198
199	return strcmp(print_fmt, expected);
200}
201
202FIXTURE(user) {
203	int status_fd;
204	int data_fd;
205	int enable_fd;
206	int check;
207	bool umount;
208};
209
210FIXTURE_SETUP(user) {
211	USER_EVENT_FIXTURE_SETUP(return, self->umount);
212
213	self->status_fd = open(status_file, O_RDONLY);
214	ASSERT_NE(-1, self->status_fd);
215
216	self->data_fd = open(data_file, O_RDWR);
217	ASSERT_NE(-1, self->data_fd);
218
219	self->enable_fd = -1;
220}
221
222FIXTURE_TEARDOWN(user) {
223	USER_EVENT_FIXTURE_TEARDOWN(self->umount);
224
225	close(self->status_fd);
226	close(self->data_fd);
227
228	if (self->enable_fd != -1) {
229		write(self->enable_fd, "0", sizeof("0"));
230		close(self->enable_fd);
231	}
232
233	if (clear(&self->check) != 0)
234		printf("WARNING: Clear didn't work!\n");
235}
236
237TEST_F(user, register_events) {
238	struct user_reg reg = {0};
239	struct user_unreg unreg = {0};
240
241	reg.size = sizeof(reg);
242	reg.name_args = (__u64)"__test_event u32 field1; u32 field2";
243	reg.enable_bit = 31;
244	reg.enable_addr = (__u64)&self->check;
245	reg.enable_size = sizeof(self->check);
246
247	unreg.size = sizeof(unreg);
248	unreg.disable_bit = 31;
249	unreg.disable_addr = (__u64)&self->check;
250
251	/* Register should work */
252	ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSREG, &reg));
253	ASSERT_EQ(0, reg.write_index);
254
255	/* Multiple registers to the same addr + bit should fail */
256	ASSERT_EQ(-1, ioctl(self->data_fd, DIAG_IOCSREG, &reg));
257	ASSERT_EQ(EADDRINUSE, errno);
258
259	/* Multiple registers to same name should result in same index */
260	reg.enable_bit = 30;
261	ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSREG, &reg));
262	ASSERT_EQ(0, reg.write_index);
263
264	/* Multiple registers to same name but different args should fail */
265	reg.enable_bit = 29;
266	reg.name_args = (__u64)"__test_event u32 field1;";
267	ASSERT_EQ(-1, ioctl(self->data_fd, DIAG_IOCSREG, &reg));
268	ASSERT_EQ(EADDRINUSE, errno);
269
270	/* Ensure disabled */
271	self->enable_fd = open(enable_file, O_RDWR);
272	ASSERT_NE(-1, self->enable_fd);
273	ASSERT_NE(-1, write(self->enable_fd, "0", sizeof("0")))
274
275	/* Enable event and ensure bits updated in status */
276	ASSERT_NE(-1, write(self->enable_fd, "1", sizeof("1")))
277	ASSERT_EQ(1 << reg.enable_bit, self->check);
278
279	/* Disable event and ensure bits updated in status */
280	ASSERT_NE(-1, write(self->enable_fd, "0", sizeof("0")))
281	ASSERT_EQ(0, self->check);
282
283	/* File still open should return -EBUSY for delete */
284	ASSERT_EQ(-1, ioctl(self->data_fd, DIAG_IOCSDEL, "__test_event"));
285	ASSERT_EQ(EBUSY, errno);
286
287	/* Unregister */
288	ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSUNREG, &unreg));
289	unreg.disable_bit = 30;
290	ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSUNREG, &unreg));
291
292	/* Delete should have been auto-done after close and unregister */
293	close(self->data_fd);
294
295	ASSERT_EQ(true, wait_for_delete());
296}
297
298TEST_F(user, write_events) {
299	struct user_reg reg = {0};
300	struct iovec io[3];
301	__u32 field1, field2;
302	int before = 0, after = 0;
303
304	reg.size = sizeof(reg);
305	reg.name_args = (__u64)"__test_event u32 field1; u32 field2";
306	reg.enable_bit = 31;
307	reg.enable_addr = (__u64)&self->check;
308	reg.enable_size = sizeof(self->check);
309
310	field1 = 1;
311	field2 = 2;
312
313	io[0].iov_base = &reg.write_index;
314	io[0].iov_len = sizeof(reg.write_index);
315	io[1].iov_base = &field1;
316	io[1].iov_len = sizeof(field1);
317	io[2].iov_base = &field2;
318	io[2].iov_len = sizeof(field2);
319
320	/* Register should work */
321	ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSREG, &reg));
322	ASSERT_EQ(0, reg.write_index);
323	ASSERT_EQ(0, self->check);
324
325	/* Write should fail on invalid slot with ENOENT */
326	io[0].iov_base = &field2;
327	io[0].iov_len = sizeof(field2);
328	ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3));
329	ASSERT_EQ(ENOENT, errno);
330	io[0].iov_base = &reg.write_index;
331	io[0].iov_len = sizeof(reg.write_index);
332
333	/* Write should return -EBADF when event is not enabled */
334	ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3));
335	ASSERT_EQ(EBADF, errno);
336
337	/* Enable event */
338	self->enable_fd = open(enable_file, O_RDWR);
339	ASSERT_NE(-1, write(self->enable_fd, "1", sizeof("1")))
340
341	/* Event should now be enabled */
342	ASSERT_NE(1 << reg.enable_bit, self->check);
343
344	/* Write should make it out to ftrace buffers */
345	before = trace_bytes();
346	ASSERT_NE(-1, writev(self->data_fd, (const struct iovec *)io, 3));
347	after = trace_bytes();
348	ASSERT_GT(after, before);
349
350	/* Negative index should fail with EINVAL */
351	reg.write_index = -1;
352	ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3));
353	ASSERT_EQ(EINVAL, errno);
354}
355
356TEST_F(user, write_empty_events) {
357	struct user_reg reg = {0};
358	struct iovec io[1];
359	int before = 0, after = 0;
360
361	reg.size = sizeof(reg);
362	reg.name_args = (__u64)"__test_event";
363	reg.enable_bit = 31;
364	reg.enable_addr = (__u64)&self->check;
365	reg.enable_size = sizeof(self->check);
366
367	io[0].iov_base = &reg.write_index;
368	io[0].iov_len = sizeof(reg.write_index);
369
370	/* Register should work */
371	ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSREG, &reg));
372	ASSERT_EQ(0, reg.write_index);
373	ASSERT_EQ(0, self->check);
374
375	/* Enable event */
376	self->enable_fd = open(enable_file, O_RDWR);
377	ASSERT_NE(-1, write(self->enable_fd, "1", sizeof("1")))
378
379	/* Event should now be enabled */
380	ASSERT_EQ(1 << reg.enable_bit, self->check);
381
382	/* Write should make it out to ftrace buffers */
383	before = trace_bytes();
384	ASSERT_NE(-1, writev(self->data_fd, (const struct iovec *)io, 1));
385	after = trace_bytes();
386	ASSERT_GT(after, before);
387}
388
389TEST_F(user, write_fault) {
390	struct user_reg reg = {0};
391	struct iovec io[2];
392	int l = sizeof(__u64);
393	void *anon;
394
395	reg.size = sizeof(reg);
396	reg.name_args = (__u64)"__test_event u64 anon";
397	reg.enable_bit = 31;
398	reg.enable_addr = (__u64)&self->check;
399	reg.enable_size = sizeof(self->check);
400
401	anon = mmap(NULL, l, PROT_READ, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
402	ASSERT_NE(MAP_FAILED, anon);
403
404	io[0].iov_base = &reg.write_index;
405	io[0].iov_len = sizeof(reg.write_index);
406	io[1].iov_base = anon;
407	io[1].iov_len = l;
408
409	/* Register should work */
410	ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSREG, &reg));
411	ASSERT_EQ(0, reg.write_index);
412
413	/* Enable event */
414	self->enable_fd = open(enable_file, O_RDWR);
415	ASSERT_NE(-1, write(self->enable_fd, "1", sizeof("1")))
416
417	/* Write should work normally */
418	ASSERT_NE(-1, writev(self->data_fd, (const struct iovec *)io, 2));
419
420	/* Faulted data should zero fill and work */
421	ASSERT_EQ(0, madvise(anon, l, MADV_DONTNEED));
422	ASSERT_NE(-1, writev(self->data_fd, (const struct iovec *)io, 2));
423	ASSERT_EQ(0, munmap(anon, l));
424}
425
426TEST_F(user, write_validator) {
427	struct user_reg reg = {0};
428	struct iovec io[3];
429	int loc, bytes;
430	char data[8];
431	int before = 0, after = 0;
432
433	reg.size = sizeof(reg);
434	reg.name_args = (__u64)"__test_event __rel_loc char[] data";
435	reg.enable_bit = 31;
436	reg.enable_addr = (__u64)&self->check;
437	reg.enable_size = sizeof(self->check);
438
439	/* Register should work */
440	ASSERT_EQ(0, ioctl(self->data_fd, DIAG_IOCSREG, &reg));
441	ASSERT_EQ(0, reg.write_index);
442	ASSERT_EQ(0, self->check);
443
444	io[0].iov_base = &reg.write_index;
445	io[0].iov_len = sizeof(reg.write_index);
446	io[1].iov_base = &loc;
447	io[1].iov_len = sizeof(loc);
448	io[2].iov_base = data;
449	bytes = snprintf(data, sizeof(data), "Test") + 1;
450	io[2].iov_len = bytes;
451
452	/* Undersized write should fail */
453	ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 1));
454	ASSERT_EQ(EINVAL, errno);
455
456	/* Enable event */
457	self->enable_fd = open(enable_file, O_RDWR);
458	ASSERT_NE(-1, write(self->enable_fd, "1", sizeof("1")))
459
460	/* Event should now be enabled */
461	ASSERT_EQ(1 << reg.enable_bit, self->check);
462
463	/* Full in-bounds write should work */
464	before = trace_bytes();
465	loc = DYN_LOC(0, bytes);
466	ASSERT_NE(-1, writev(self->data_fd, (const struct iovec *)io, 3));
467	after = trace_bytes();
468	ASSERT_GT(after, before);
469
470	/* Out of bounds write should fault (offset way out) */
471	loc = DYN_LOC(1024, bytes);
472	ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3));
473	ASSERT_EQ(EFAULT, errno);
474
475	/* Out of bounds write should fault (offset 1 byte out) */
476	loc = DYN_LOC(1, bytes);
477	ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3));
478	ASSERT_EQ(EFAULT, errno);
479
480	/* Out of bounds write should fault (size way out) */
481	loc = DYN_LOC(0, bytes + 1024);
482	ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3));
483	ASSERT_EQ(EFAULT, errno);
484
485	/* Out of bounds write should fault (size 1 byte out) */
486	loc = DYN_LOC(0, bytes + 1);
487	ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3));
488	ASSERT_EQ(EFAULT, errno);
489
490	/* Non-Null should fault */
491	memset(data, 'A', sizeof(data));
492	loc = DYN_LOC(0, bytes);
493	ASSERT_EQ(-1, writev(self->data_fd, (const struct iovec *)io, 3));
494	ASSERT_EQ(EFAULT, errno);
495}
496
497TEST_F(user, print_fmt) {
498	int ret;
499
500	ret = check_print_fmt("__test_event __rel_loc char[] data",
501			      "print fmt: \"data=%s\", __get_rel_str(data)",
502			      &self->check);
503	ASSERT_EQ(0, ret);
504
505	ret = check_print_fmt("__test_event __data_loc char[] data",
506			      "print fmt: \"data=%s\", __get_str(data)",
507			      &self->check);
508	ASSERT_EQ(0, ret);
509
510	ret = check_print_fmt("__test_event s64 data",
511			      "print fmt: \"data=%lld\", REC->data",
512			      &self->check);
513	ASSERT_EQ(0, ret);
514
515	ret = check_print_fmt("__test_event u64 data",
516			      "print fmt: \"data=%llu\", REC->data",
517			      &self->check);
518	ASSERT_EQ(0, ret);
519
520	ret = check_print_fmt("__test_event s32 data",
521			      "print fmt: \"data=%d\", REC->data",
522			      &self->check);
523	ASSERT_EQ(0, ret);
524
525	ret = check_print_fmt("__test_event u32 data",
526			      "print fmt: \"data=%u\", REC->data",
527			      &self->check);
528	ASSERT_EQ(0, ret);
529
530	ret = check_print_fmt("__test_event int data",
531			      "print fmt: \"data=%d\", REC->data",
532			      &self->check);
533	ASSERT_EQ(0, ret);
534
535	ret = check_print_fmt("__test_event unsigned int data",
536			      "print fmt: \"data=%u\", REC->data",
537			      &self->check);
538	ASSERT_EQ(0, ret);
539
540	ret = check_print_fmt("__test_event s16 data",
541			      "print fmt: \"data=%d\", REC->data",
542			      &self->check);
543	ASSERT_EQ(0, ret);
544
545	ret = check_print_fmt("__test_event u16 data",
546			      "print fmt: \"data=%u\", REC->data",
547			      &self->check);
548	ASSERT_EQ(0, ret);
549
550	ret = check_print_fmt("__test_event short data",
551			      "print fmt: \"data=%d\", REC->data",
552			      &self->check);
553	ASSERT_EQ(0, ret);
554
555	ret = check_print_fmt("__test_event unsigned short data",
556			      "print fmt: \"data=%u\", REC->data",
557			      &self->check);
558	ASSERT_EQ(0, ret);
559
560	ret = check_print_fmt("__test_event s8 data",
561			      "print fmt: \"data=%d\", REC->data",
562			      &self->check);
563	ASSERT_EQ(0, ret);
564
565	ret = check_print_fmt("__test_event u8 data",
566			      "print fmt: \"data=%u\", REC->data",
567			      &self->check);
568	ASSERT_EQ(0, ret);
569
570	ret = check_print_fmt("__test_event char data",
571			      "print fmt: \"data=%d\", REC->data",
572			      &self->check);
573	ASSERT_EQ(0, ret);
574
575	ret = check_print_fmt("__test_event unsigned char data",
576			      "print fmt: \"data=%u\", REC->data",
577			      &self->check);
578	ASSERT_EQ(0, ret);
579
580	ret = check_print_fmt("__test_event char[4] data",
581			      "print fmt: \"data=%s\", REC->data",
582			      &self->check);
583	ASSERT_EQ(0, ret);
584}
585
586int main(int argc, char **argv)
587{
588	return test_harness_run(argc, argv);
589}
590