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1// SPDX-License-Identifier: GPL-2.0
2/* Copyright (c) 2022 Meta Platforms, Inc. and affiliates. */
3
4#define _GNU_SOURCE
5#include <linux/compiler.h>
6#include <linux/ring_buffer.h>
7#include <pthread.h>
8#include <stdio.h>
9#include <stdlib.h>
10#include <sys/mman.h>
11#include <sys/syscall.h>
12#include <sys/sysinfo.h>
13#include <test_progs.h>
14#include <uapi/linux/bpf.h>
15#include <unistd.h>
16
17#include "user_ringbuf_fail.skel.h"
18#include "user_ringbuf_success.skel.h"
19
20#include "../progs/test_user_ringbuf.h"
21
22static const long c_sample_size = sizeof(struct sample) + BPF_RINGBUF_HDR_SZ;
23static const long c_ringbuf_size = 1 << 12; /* 1 small page */
24static const long c_max_entries = c_ringbuf_size / c_sample_size;
25
26static void drain_current_samples(void)
27{
28 syscall(__NR_getpgid);
29}
30
31static int write_samples(struct user_ring_buffer *ringbuf, uint32_t num_samples)
32{
33 int i, err = 0;
34
35 /* Write some number of samples to the ring buffer. */
36 for (i = 0; i < num_samples; i++) {
37 struct sample *entry;
38 int read;
39
40 entry = user_ring_buffer__reserve(ringbuf, sizeof(*entry));
41 if (!entry) {
42 err = -errno;
43 goto done;
44 }
45
46 entry->pid = getpid();
47 entry->seq = i;
48 entry->value = i * i;
49
50 read = snprintf(entry->comm, sizeof(entry->comm), "%u", i);
51 if (read <= 0) {
52 /* Assert on the error path to avoid spamming logs with
53 * mostly success messages.
54 */
55 ASSERT_GT(read, 0, "snprintf_comm");
56 err = read;
57 user_ring_buffer__discard(ringbuf, entry);
58 goto done;
59 }
60
61 user_ring_buffer__submit(ringbuf, entry);
62 }
63
64done:
65 drain_current_samples();
66
67 return err;
68}
69
70static struct user_ringbuf_success *open_load_ringbuf_skel(void)
71{
72 struct user_ringbuf_success *skel;
73 int err;
74
75 skel = user_ringbuf_success__open();
76 if (!ASSERT_OK_PTR(skel, "skel_open"))
77 return NULL;
78
79 err = bpf_map__set_max_entries(skel->maps.user_ringbuf, c_ringbuf_size);
80 if (!ASSERT_OK(err, "set_max_entries"))
81 goto cleanup;
82
83 err = bpf_map__set_max_entries(skel->maps.kernel_ringbuf, c_ringbuf_size);
84 if (!ASSERT_OK(err, "set_max_entries"))
85 goto cleanup;
86
87 err = user_ringbuf_success__load(skel);
88 if (!ASSERT_OK(err, "skel_load"))
89 goto cleanup;
90
91 return skel;
92
93cleanup:
94 user_ringbuf_success__destroy(skel);
95 return NULL;
96}
97
98static void test_user_ringbuf_mappings(void)
99{
100 int err, rb_fd;
101 int page_size = getpagesize();
102 void *mmap_ptr;
103 struct user_ringbuf_success *skel;
104
105 skel = open_load_ringbuf_skel();
106 if (!skel)
107 return;
108
109 rb_fd = bpf_map__fd(skel->maps.user_ringbuf);
110 /* cons_pos can be mapped R/O, can't add +X with mprotect. */
111 mmap_ptr = mmap(NULL, page_size, PROT_READ, MAP_SHARED, rb_fd, 0);
112 ASSERT_OK_PTR(mmap_ptr, "ro_cons_pos");
113 ASSERT_ERR(mprotect(mmap_ptr, page_size, PROT_WRITE), "write_cons_pos_protect");
114 ASSERT_ERR(mprotect(mmap_ptr, page_size, PROT_EXEC), "exec_cons_pos_protect");
115 ASSERT_ERR_PTR(mremap(mmap_ptr, 0, 4 * page_size, MREMAP_MAYMOVE), "wr_prod_pos");
116 err = -errno;
117 ASSERT_ERR(err, "wr_prod_pos_err");
118 ASSERT_OK(munmap(mmap_ptr, page_size), "unmap_ro_cons");
119
120 /* prod_pos can be mapped RW, can't add +X with mprotect. */
121 mmap_ptr = mmap(NULL, page_size, PROT_READ | PROT_WRITE, MAP_SHARED,
122 rb_fd, page_size);
123 ASSERT_OK_PTR(mmap_ptr, "rw_prod_pos");
124 ASSERT_ERR(mprotect(mmap_ptr, page_size, PROT_EXEC), "exec_prod_pos_protect");
125 err = -errno;
126 ASSERT_ERR(err, "wr_prod_pos_err");
127 ASSERT_OK(munmap(mmap_ptr, page_size), "unmap_rw_prod");
128
129 /* data pages can be mapped RW, can't add +X with mprotect. */
130 mmap_ptr = mmap(NULL, page_size, PROT_WRITE, MAP_SHARED, rb_fd,
131 2 * page_size);
132 ASSERT_OK_PTR(mmap_ptr, "rw_data");
133 ASSERT_ERR(mprotect(mmap_ptr, page_size, PROT_EXEC), "exec_data_protect");
134 err = -errno;
135 ASSERT_ERR(err, "exec_data_err");
136 ASSERT_OK(munmap(mmap_ptr, page_size), "unmap_rw_data");
137
138 user_ringbuf_success__destroy(skel);
139}
140
141static int load_skel_create_ringbufs(struct user_ringbuf_success **skel_out,
142 struct ring_buffer **kern_ringbuf_out,
143 ring_buffer_sample_fn callback,
144 struct user_ring_buffer **user_ringbuf_out)
145{
146 struct user_ringbuf_success *skel;
147 struct ring_buffer *kern_ringbuf = NULL;
148 struct user_ring_buffer *user_ringbuf = NULL;
149 int err = -ENOMEM, rb_fd;
150
151 skel = open_load_ringbuf_skel();
152 if (!skel)
153 return err;
154
155 /* only trigger BPF program for current process */
156 skel->bss->pid = getpid();
157
158 if (kern_ringbuf_out) {
159 rb_fd = bpf_map__fd(skel->maps.kernel_ringbuf);
160 kern_ringbuf = ring_buffer__new(rb_fd, callback, skel, NULL);
161 if (!ASSERT_OK_PTR(kern_ringbuf, "kern_ringbuf_create"))
162 goto cleanup;
163
164 *kern_ringbuf_out = kern_ringbuf;
165 }
166
167 if (user_ringbuf_out) {
168 rb_fd = bpf_map__fd(skel->maps.user_ringbuf);
169 user_ringbuf = user_ring_buffer__new(rb_fd, NULL);
170 if (!ASSERT_OK_PTR(user_ringbuf, "user_ringbuf_create"))
171 goto cleanup;
172
173 *user_ringbuf_out = user_ringbuf;
174 ASSERT_EQ(skel->bss->read, 0, "no_reads_after_load");
175 }
176
177 err = user_ringbuf_success__attach(skel);
178 if (!ASSERT_OK(err, "skel_attach"))
179 goto cleanup;
180
181 *skel_out = skel;
182 return 0;
183
184cleanup:
185 if (kern_ringbuf_out)
186 *kern_ringbuf_out = NULL;
187 if (user_ringbuf_out)
188 *user_ringbuf_out = NULL;
189 ring_buffer__free(kern_ringbuf);
190 user_ring_buffer__free(user_ringbuf);
191 user_ringbuf_success__destroy(skel);
192 return err;
193}
194
195static int load_skel_create_user_ringbuf(struct user_ringbuf_success **skel_out,
196 struct user_ring_buffer **ringbuf_out)
197{
198 return load_skel_create_ringbufs(skel_out, NULL, NULL, ringbuf_out);
199}
200
201static void manually_write_test_invalid_sample(struct user_ringbuf_success *skel,
202 __u32 size, __u64 producer_pos, int err)
203{
204 void *data_ptr;
205 __u64 *producer_pos_ptr;
206 int rb_fd, page_size = getpagesize();
207
208 rb_fd = bpf_map__fd(skel->maps.user_ringbuf);
209
210 ASSERT_EQ(skel->bss->read, 0, "num_samples_before_bad_sample");
211
212 /* Map the producer_pos as RW. */
213 producer_pos_ptr = mmap(NULL, page_size, PROT_READ | PROT_WRITE,
214 MAP_SHARED, rb_fd, page_size);
215 ASSERT_OK_PTR(producer_pos_ptr, "producer_pos_ptr");
216
217 /* Map the data pages as RW. */
218 data_ptr = mmap(NULL, page_size, PROT_WRITE, MAP_SHARED, rb_fd, 2 * page_size);
219 ASSERT_OK_PTR(data_ptr, "rw_data");
220
221 memset(data_ptr, 0, BPF_RINGBUF_HDR_SZ);
222 *(__u32 *)data_ptr = size;
223
224 /* Synchronizes with smp_load_acquire() in __bpf_user_ringbuf_peek() in the kernel. */
225 smp_store_release(producer_pos_ptr, producer_pos + BPF_RINGBUF_HDR_SZ);
226
227 drain_current_samples();
228 ASSERT_EQ(skel->bss->read, 0, "num_samples_after_bad_sample");
229 ASSERT_EQ(skel->bss->err, err, "err_after_bad_sample");
230
231 ASSERT_OK(munmap(producer_pos_ptr, page_size), "unmap_producer_pos");
232 ASSERT_OK(munmap(data_ptr, page_size), "unmap_data_ptr");
233}
234
235static void test_user_ringbuf_post_misaligned(void)
236{
237 struct user_ringbuf_success *skel;
238 struct user_ring_buffer *ringbuf;
239 int err;
240 __u32 size = (1 << 5) + 7;
241
242 err = load_skel_create_user_ringbuf(&skel, &ringbuf);
243 if (!ASSERT_OK(err, "misaligned_skel"))
244 return;
245
246 manually_write_test_invalid_sample(skel, size, size, -EINVAL);
247 user_ring_buffer__free(ringbuf);
248 user_ringbuf_success__destroy(skel);
249}
250
251static void test_user_ringbuf_post_producer_wrong_offset(void)
252{
253 struct user_ringbuf_success *skel;
254 struct user_ring_buffer *ringbuf;
255 int err;
256 __u32 size = (1 << 5);
257
258 err = load_skel_create_user_ringbuf(&skel, &ringbuf);
259 if (!ASSERT_OK(err, "wrong_offset_skel"))
260 return;
261
262 manually_write_test_invalid_sample(skel, size, size - 8, -EINVAL);
263 user_ring_buffer__free(ringbuf);
264 user_ringbuf_success__destroy(skel);
265}
266
267static void test_user_ringbuf_post_larger_than_ringbuf_sz(void)
268{
269 struct user_ringbuf_success *skel;
270 struct user_ring_buffer *ringbuf;
271 int err;
272 __u32 size = c_ringbuf_size;
273
274 err = load_skel_create_user_ringbuf(&skel, &ringbuf);
275 if (!ASSERT_OK(err, "huge_sample_skel"))
276 return;
277
278 manually_write_test_invalid_sample(skel, size, size, -E2BIG);
279 user_ring_buffer__free(ringbuf);
280 user_ringbuf_success__destroy(skel);
281}
282
283static void test_user_ringbuf_basic(void)
284{
285 struct user_ringbuf_success *skel;
286 struct user_ring_buffer *ringbuf;
287 int err;
288
289 err = load_skel_create_user_ringbuf(&skel, &ringbuf);
290 if (!ASSERT_OK(err, "ringbuf_basic_skel"))
291 return;
292
293 ASSERT_EQ(skel->bss->read, 0, "num_samples_read_before");
294
295 err = write_samples(ringbuf, 2);
296 if (!ASSERT_OK(err, "write_samples"))
297 goto cleanup;
298
299 ASSERT_EQ(skel->bss->read, 2, "num_samples_read_after");
300
301cleanup:
302 user_ring_buffer__free(ringbuf);
303 user_ringbuf_success__destroy(skel);
304}
305
306static void test_user_ringbuf_sample_full_ring_buffer(void)
307{
308 struct user_ringbuf_success *skel;
309 struct user_ring_buffer *ringbuf;
310 int err;
311 void *sample;
312
313 err = load_skel_create_user_ringbuf(&skel, &ringbuf);
314 if (!ASSERT_OK(err, "ringbuf_full_sample_skel"))
315 return;
316
317 sample = user_ring_buffer__reserve(ringbuf, c_ringbuf_size - BPF_RINGBUF_HDR_SZ);
318 if (!ASSERT_OK_PTR(sample, "full_sample"))
319 goto cleanup;
320
321 user_ring_buffer__submit(ringbuf, sample);
322 ASSERT_EQ(skel->bss->read, 0, "num_samples_read_before");
323 drain_current_samples();
324 ASSERT_EQ(skel->bss->read, 1, "num_samples_read_after");
325
326cleanup:
327 user_ring_buffer__free(ringbuf);
328 user_ringbuf_success__destroy(skel);
329}
330
331static void test_user_ringbuf_post_alignment_autoadjust(void)
332{
333 struct user_ringbuf_success *skel;
334 struct user_ring_buffer *ringbuf;
335 struct sample *sample;
336 int err;
337
338 err = load_skel_create_user_ringbuf(&skel, &ringbuf);
339 if (!ASSERT_OK(err, "ringbuf_align_autoadjust_skel"))
340 return;
341
342 /* libbpf should automatically round any sample up to an 8-byte alignment. */
343 sample = user_ring_buffer__reserve(ringbuf, sizeof(*sample) + 1);
344 ASSERT_OK_PTR(sample, "reserve_autoaligned");
345 user_ring_buffer__submit(ringbuf, sample);
346
347 ASSERT_EQ(skel->bss->read, 0, "num_samples_read_before");
348 drain_current_samples();
349 ASSERT_EQ(skel->bss->read, 1, "num_samples_read_after");
350
351 user_ring_buffer__free(ringbuf);
352 user_ringbuf_success__destroy(skel);
353}
354
355static void test_user_ringbuf_overfill(void)
356{
357 struct user_ringbuf_success *skel;
358 struct user_ring_buffer *ringbuf;
359 int err;
360
361 err = load_skel_create_user_ringbuf(&skel, &ringbuf);
362 if (err)
363 return;
364
365 err = write_samples(ringbuf, c_max_entries * 5);
366 ASSERT_ERR(err, "write_samples");
367 ASSERT_EQ(skel->bss->read, c_max_entries, "max_entries");
368
369 user_ring_buffer__free(ringbuf);
370 user_ringbuf_success__destroy(skel);
371}
372
373static void test_user_ringbuf_discards_properly_ignored(void)
374{
375 struct user_ringbuf_success *skel;
376 struct user_ring_buffer *ringbuf;
377 int err, num_discarded = 0;
378 __u64 *token;
379
380 err = load_skel_create_user_ringbuf(&skel, &ringbuf);
381 if (err)
382 return;
383
384 ASSERT_EQ(skel->bss->read, 0, "num_samples_read_before");
385
386 while (1) {
387 /* Write samples until the buffer is full. */
388 token = user_ring_buffer__reserve(ringbuf, sizeof(*token));
389 if (!token)
390 break;
391
392 user_ring_buffer__discard(ringbuf, token);
393 num_discarded++;
394 }
395
396 if (!ASSERT_GE(num_discarded, 0, "num_discarded"))
397 goto cleanup;
398
399 /* Should not read any samples, as they are all discarded. */
400 ASSERT_EQ(skel->bss->read, 0, "num_pre_kick");
401 drain_current_samples();
402 ASSERT_EQ(skel->bss->read, 0, "num_post_kick");
403
404 /* Now that the ring buffer has been drained, we should be able to
405 * reserve another token.
406 */
407 token = user_ring_buffer__reserve(ringbuf, sizeof(*token));
408
409 if (!ASSERT_OK_PTR(token, "new_token"))
410 goto cleanup;
411
412 user_ring_buffer__discard(ringbuf, token);
413cleanup:
414 user_ring_buffer__free(ringbuf);
415 user_ringbuf_success__destroy(skel);
416}
417
418static void test_user_ringbuf_loop(void)
419{
420 struct user_ringbuf_success *skel;
421 struct user_ring_buffer *ringbuf;
422 uint32_t total_samples = 8192;
423 uint32_t remaining_samples = total_samples;
424 int err;
425
426 BUILD_BUG_ON(total_samples <= c_max_entries);
427 err = load_skel_create_user_ringbuf(&skel, &ringbuf);
428 if (err)
429 return;
430
431 do {
432 uint32_t curr_samples;
433
434 curr_samples = remaining_samples > c_max_entries
435 ? c_max_entries : remaining_samples;
436 err = write_samples(ringbuf, curr_samples);
437 if (err != 0) {
438 /* Assert inside of if statement to avoid flooding logs
439 * on the success path.
440 */
441 ASSERT_OK(err, "write_samples");
442 goto cleanup;
443 }
444
445 remaining_samples -= curr_samples;
446 ASSERT_EQ(skel->bss->read, total_samples - remaining_samples,
447 "current_batched_entries");
448 } while (remaining_samples > 0);
449 ASSERT_EQ(skel->bss->read, total_samples, "total_batched_entries");
450
451cleanup:
452 user_ring_buffer__free(ringbuf);
453 user_ringbuf_success__destroy(skel);
454}
455
456static int send_test_message(struct user_ring_buffer *ringbuf,
457 enum test_msg_op op, s64 operand_64,
458 s32 operand_32)
459{
460 struct test_msg *msg;
461
462 msg = user_ring_buffer__reserve(ringbuf, sizeof(*msg));
463 if (!msg) {
464 /* Assert on the error path to avoid spamming logs with mostly
465 * success messages.
466 */
467 ASSERT_OK_PTR(msg, "reserve_msg");
468 return -ENOMEM;
469 }
470
471 msg->msg_op = op;
472
473 switch (op) {
474 case TEST_MSG_OP_INC64:
475 case TEST_MSG_OP_MUL64:
476 msg->operand_64 = operand_64;
477 break;
478 case TEST_MSG_OP_INC32:
479 case TEST_MSG_OP_MUL32:
480 msg->operand_32 = operand_32;
481 break;
482 default:
483 PRINT_FAIL("Invalid operand %d\n", op);
484 user_ring_buffer__discard(ringbuf, msg);
485 return -EINVAL;
486 }
487
488 user_ring_buffer__submit(ringbuf, msg);
489
490 return 0;
491}
492
493static void kick_kernel_read_messages(void)
494{
495 syscall(__NR_prctl);
496}
497
498static int handle_kernel_msg(void *ctx, void *data, size_t len)
499{
500 struct user_ringbuf_success *skel = ctx;
501 struct test_msg *msg = data;
502
503 switch (msg->msg_op) {
504 case TEST_MSG_OP_INC64:
505 skel->bss->user_mutated += msg->operand_64;
506 return 0;
507 case TEST_MSG_OP_INC32:
508 skel->bss->user_mutated += msg->operand_32;
509 return 0;
510 case TEST_MSG_OP_MUL64:
511 skel->bss->user_mutated *= msg->operand_64;
512 return 0;
513 case TEST_MSG_OP_MUL32:
514 skel->bss->user_mutated *= msg->operand_32;
515 return 0;
516 default:
517 fprintf(stderr, "Invalid operand %d\n", msg->msg_op);
518 return -EINVAL;
519 }
520}
521
522static void drain_kernel_messages_buffer(struct ring_buffer *kern_ringbuf,
523 struct user_ringbuf_success *skel)
524{
525 int cnt;
526
527 cnt = ring_buffer__consume(kern_ringbuf);
528 ASSERT_EQ(cnt, 8, "consume_kern_ringbuf");
529 ASSERT_OK(skel->bss->err, "consume_kern_ringbuf_err");
530}
531
532static void test_user_ringbuf_msg_protocol(void)
533{
534 struct user_ringbuf_success *skel;
535 struct user_ring_buffer *user_ringbuf;
536 struct ring_buffer *kern_ringbuf;
537 int err, i;
538 __u64 expected_kern = 0;
539
540 err = load_skel_create_ringbufs(&skel, &kern_ringbuf, handle_kernel_msg, &user_ringbuf);
541 if (!ASSERT_OK(err, "create_ringbufs"))
542 return;
543
544 for (i = 0; i < 64; i++) {
545 enum test_msg_op op = i % TEST_MSG_OP_NUM_OPS;
546 __u64 operand_64 = TEST_OP_64;
547 __u32 operand_32 = TEST_OP_32;
548
549 err = send_test_message(user_ringbuf, op, operand_64, operand_32);
550 if (err) {
551 /* Only assert on a failure to avoid spamming success logs. */
552 ASSERT_OK(err, "send_test_message");
553 goto cleanup;
554 }
555
556 switch (op) {
557 case TEST_MSG_OP_INC64:
558 expected_kern += operand_64;
559 break;
560 case TEST_MSG_OP_INC32:
561 expected_kern += operand_32;
562 break;
563 case TEST_MSG_OP_MUL64:
564 expected_kern *= operand_64;
565 break;
566 case TEST_MSG_OP_MUL32:
567 expected_kern *= operand_32;
568 break;
569 default:
570 PRINT_FAIL("Unexpected op %d\n", op);
571 goto cleanup;
572 }
573
574 if (i % 8 == 0) {
575 kick_kernel_read_messages();
576 ASSERT_EQ(skel->bss->kern_mutated, expected_kern, "expected_kern");
577 ASSERT_EQ(skel->bss->err, 0, "bpf_prog_err");
578 drain_kernel_messages_buffer(kern_ringbuf, skel);
579 }
580 }
581
582cleanup:
583 ring_buffer__free(kern_ringbuf);
584 user_ring_buffer__free(user_ringbuf);
585 user_ringbuf_success__destroy(skel);
586}
587
588static void *kick_kernel_cb(void *arg)
589{
590 /* Kick the kernel, causing it to drain the ring buffer and then wake
591 * up the test thread waiting on epoll.
592 */
593 syscall(__NR_prlimit64);
594
595 return NULL;
596}
597
598static int spawn_kick_thread_for_poll(void)
599{
600 pthread_t thread;
601
602 return pthread_create(&thread, NULL, kick_kernel_cb, NULL);
603}
604
605static void test_user_ringbuf_blocking_reserve(void)
606{
607 struct user_ringbuf_success *skel;
608 struct user_ring_buffer *ringbuf;
609 int err, num_written = 0;
610 __u64 *token;
611
612 err = load_skel_create_user_ringbuf(&skel, &ringbuf);
613 if (err)
614 return;
615
616 ASSERT_EQ(skel->bss->read, 0, "num_samples_read_before");
617
618 while (1) {
619 /* Write samples until the buffer is full. */
620 token = user_ring_buffer__reserve(ringbuf, sizeof(*token));
621 if (!token)
622 break;
623
624 *token = 0xdeadbeef;
625
626 user_ring_buffer__submit(ringbuf, token);
627 num_written++;
628 }
629
630 if (!ASSERT_GE(num_written, 0, "num_written"))
631 goto cleanup;
632
633 /* Should not have read any samples until the kernel is kicked. */
634 ASSERT_EQ(skel->bss->read, 0, "num_pre_kick");
635
636 /* We correctly time out after 1 second, without a sample. */
637 token = user_ring_buffer__reserve_blocking(ringbuf, sizeof(*token), 1000);
638 if (!ASSERT_EQ(token, NULL, "pre_kick_timeout_token"))
639 goto cleanup;
640
641 err = spawn_kick_thread_for_poll();
642 if (!ASSERT_EQ(err, 0, "deferred_kick_thread\n"))
643 goto cleanup;
644
645 /* After spawning another thread that asychronously kicks the kernel to
646 * drain the messages, we're able to block and successfully get a
647 * sample once we receive an event notification.
648 */
649 token = user_ring_buffer__reserve_blocking(ringbuf, sizeof(*token), 10000);
650
651 if (!ASSERT_OK_PTR(token, "block_token"))
652 goto cleanup;
653
654 ASSERT_GT(skel->bss->read, 0, "num_post_kill");
655 ASSERT_LE(skel->bss->read, num_written, "num_post_kill");
656 ASSERT_EQ(skel->bss->err, 0, "err_post_poll");
657 user_ring_buffer__discard(ringbuf, token);
658
659cleanup:
660 user_ring_buffer__free(ringbuf);
661 user_ringbuf_success__destroy(skel);
662}
663
664#define SUCCESS_TEST(_func) { _func, #_func }
665
666static struct {
667 void (*test_callback)(void);
668 const char *test_name;
669} success_tests[] = {
670 SUCCESS_TEST(test_user_ringbuf_mappings),
671 SUCCESS_TEST(test_user_ringbuf_post_misaligned),
672 SUCCESS_TEST(test_user_ringbuf_post_producer_wrong_offset),
673 SUCCESS_TEST(test_user_ringbuf_post_larger_than_ringbuf_sz),
674 SUCCESS_TEST(test_user_ringbuf_basic),
675 SUCCESS_TEST(test_user_ringbuf_sample_full_ring_buffer),
676 SUCCESS_TEST(test_user_ringbuf_post_alignment_autoadjust),
677 SUCCESS_TEST(test_user_ringbuf_overfill),
678 SUCCESS_TEST(test_user_ringbuf_discards_properly_ignored),
679 SUCCESS_TEST(test_user_ringbuf_loop),
680 SUCCESS_TEST(test_user_ringbuf_msg_protocol),
681 SUCCESS_TEST(test_user_ringbuf_blocking_reserve),
682};
683
684void test_user_ringbuf(void)
685{
686 int i;
687
688 for (i = 0; i < ARRAY_SIZE(success_tests); i++) {
689 if (!test__start_subtest(success_tests[i].test_name))
690 continue;
691
692 success_tests[i].test_callback();
693 }
694
695 RUN_TESTS(user_ringbuf_fail);
696}
1// SPDX-License-Identifier: GPL-2.0
2/* Copyright (c) 2022 Meta Platforms, Inc. and affiliates. */
3
4#define _GNU_SOURCE
5#include <linux/compiler.h>
6#include <linux/ring_buffer.h>
7#include <pthread.h>
8#include <stdio.h>
9#include <stdlib.h>
10#include <sys/mman.h>
11#include <sys/syscall.h>
12#include <sys/sysinfo.h>
13#include <test_progs.h>
14#include <uapi/linux/bpf.h>
15#include <unistd.h>
16
17#include "user_ringbuf_fail.skel.h"
18#include "user_ringbuf_success.skel.h"
19
20#include "../progs/test_user_ringbuf.h"
21
22static size_t log_buf_sz = 1 << 20; /* 1 MB */
23static char obj_log_buf[1048576];
24static const long c_sample_size = sizeof(struct sample) + BPF_RINGBUF_HDR_SZ;
25static const long c_ringbuf_size = 1 << 12; /* 1 small page */
26static const long c_max_entries = c_ringbuf_size / c_sample_size;
27
28static void drain_current_samples(void)
29{
30 syscall(__NR_getpgid);
31}
32
33static int write_samples(struct user_ring_buffer *ringbuf, uint32_t num_samples)
34{
35 int i, err = 0;
36
37 /* Write some number of samples to the ring buffer. */
38 for (i = 0; i < num_samples; i++) {
39 struct sample *entry;
40 int read;
41
42 entry = user_ring_buffer__reserve(ringbuf, sizeof(*entry));
43 if (!entry) {
44 err = -errno;
45 goto done;
46 }
47
48 entry->pid = getpid();
49 entry->seq = i;
50 entry->value = i * i;
51
52 read = snprintf(entry->comm, sizeof(entry->comm), "%u", i);
53 if (read <= 0) {
54 /* Assert on the error path to avoid spamming logs with
55 * mostly success messages.
56 */
57 ASSERT_GT(read, 0, "snprintf_comm");
58 err = read;
59 user_ring_buffer__discard(ringbuf, entry);
60 goto done;
61 }
62
63 user_ring_buffer__submit(ringbuf, entry);
64 }
65
66done:
67 drain_current_samples();
68
69 return err;
70}
71
72static struct user_ringbuf_success *open_load_ringbuf_skel(void)
73{
74 struct user_ringbuf_success *skel;
75 int err;
76
77 skel = user_ringbuf_success__open();
78 if (!ASSERT_OK_PTR(skel, "skel_open"))
79 return NULL;
80
81 err = bpf_map__set_max_entries(skel->maps.user_ringbuf, c_ringbuf_size);
82 if (!ASSERT_OK(err, "set_max_entries"))
83 goto cleanup;
84
85 err = bpf_map__set_max_entries(skel->maps.kernel_ringbuf, c_ringbuf_size);
86 if (!ASSERT_OK(err, "set_max_entries"))
87 goto cleanup;
88
89 err = user_ringbuf_success__load(skel);
90 if (!ASSERT_OK(err, "skel_load"))
91 goto cleanup;
92
93 return skel;
94
95cleanup:
96 user_ringbuf_success__destroy(skel);
97 return NULL;
98}
99
100static void test_user_ringbuf_mappings(void)
101{
102 int err, rb_fd;
103 int page_size = getpagesize();
104 void *mmap_ptr;
105 struct user_ringbuf_success *skel;
106
107 skel = open_load_ringbuf_skel();
108 if (!skel)
109 return;
110
111 rb_fd = bpf_map__fd(skel->maps.user_ringbuf);
112 /* cons_pos can be mapped R/O, can't add +X with mprotect. */
113 mmap_ptr = mmap(NULL, page_size, PROT_READ, MAP_SHARED, rb_fd, 0);
114 ASSERT_OK_PTR(mmap_ptr, "ro_cons_pos");
115 ASSERT_ERR(mprotect(mmap_ptr, page_size, PROT_WRITE), "write_cons_pos_protect");
116 ASSERT_ERR(mprotect(mmap_ptr, page_size, PROT_EXEC), "exec_cons_pos_protect");
117 ASSERT_ERR_PTR(mremap(mmap_ptr, 0, 4 * page_size, MREMAP_MAYMOVE), "wr_prod_pos");
118 err = -errno;
119 ASSERT_ERR(err, "wr_prod_pos_err");
120 ASSERT_OK(munmap(mmap_ptr, page_size), "unmap_ro_cons");
121
122 /* prod_pos can be mapped RW, can't add +X with mprotect. */
123 mmap_ptr = mmap(NULL, page_size, PROT_READ | PROT_WRITE, MAP_SHARED,
124 rb_fd, page_size);
125 ASSERT_OK_PTR(mmap_ptr, "rw_prod_pos");
126 ASSERT_ERR(mprotect(mmap_ptr, page_size, PROT_EXEC), "exec_prod_pos_protect");
127 err = -errno;
128 ASSERT_ERR(err, "wr_prod_pos_err");
129 ASSERT_OK(munmap(mmap_ptr, page_size), "unmap_rw_prod");
130
131 /* data pages can be mapped RW, can't add +X with mprotect. */
132 mmap_ptr = mmap(NULL, page_size, PROT_WRITE, MAP_SHARED, rb_fd,
133 2 * page_size);
134 ASSERT_OK_PTR(mmap_ptr, "rw_data");
135 ASSERT_ERR(mprotect(mmap_ptr, page_size, PROT_EXEC), "exec_data_protect");
136 err = -errno;
137 ASSERT_ERR(err, "exec_data_err");
138 ASSERT_OK(munmap(mmap_ptr, page_size), "unmap_rw_data");
139
140 user_ringbuf_success__destroy(skel);
141}
142
143static int load_skel_create_ringbufs(struct user_ringbuf_success **skel_out,
144 struct ring_buffer **kern_ringbuf_out,
145 ring_buffer_sample_fn callback,
146 struct user_ring_buffer **user_ringbuf_out)
147{
148 struct user_ringbuf_success *skel;
149 struct ring_buffer *kern_ringbuf = NULL;
150 struct user_ring_buffer *user_ringbuf = NULL;
151 int err = -ENOMEM, rb_fd;
152
153 skel = open_load_ringbuf_skel();
154 if (!skel)
155 return err;
156
157 /* only trigger BPF program for current process */
158 skel->bss->pid = getpid();
159
160 if (kern_ringbuf_out) {
161 rb_fd = bpf_map__fd(skel->maps.kernel_ringbuf);
162 kern_ringbuf = ring_buffer__new(rb_fd, callback, skel, NULL);
163 if (!ASSERT_OK_PTR(kern_ringbuf, "kern_ringbuf_create"))
164 goto cleanup;
165
166 *kern_ringbuf_out = kern_ringbuf;
167 }
168
169 if (user_ringbuf_out) {
170 rb_fd = bpf_map__fd(skel->maps.user_ringbuf);
171 user_ringbuf = user_ring_buffer__new(rb_fd, NULL);
172 if (!ASSERT_OK_PTR(user_ringbuf, "user_ringbuf_create"))
173 goto cleanup;
174
175 *user_ringbuf_out = user_ringbuf;
176 ASSERT_EQ(skel->bss->read, 0, "no_reads_after_load");
177 }
178
179 err = user_ringbuf_success__attach(skel);
180 if (!ASSERT_OK(err, "skel_attach"))
181 goto cleanup;
182
183 *skel_out = skel;
184 return 0;
185
186cleanup:
187 if (kern_ringbuf_out)
188 *kern_ringbuf_out = NULL;
189 if (user_ringbuf_out)
190 *user_ringbuf_out = NULL;
191 ring_buffer__free(kern_ringbuf);
192 user_ring_buffer__free(user_ringbuf);
193 user_ringbuf_success__destroy(skel);
194 return err;
195}
196
197static int load_skel_create_user_ringbuf(struct user_ringbuf_success **skel_out,
198 struct user_ring_buffer **ringbuf_out)
199{
200 return load_skel_create_ringbufs(skel_out, NULL, NULL, ringbuf_out);
201}
202
203static void manually_write_test_invalid_sample(struct user_ringbuf_success *skel,
204 __u32 size, __u64 producer_pos, int err)
205{
206 void *data_ptr;
207 __u64 *producer_pos_ptr;
208 int rb_fd, page_size = getpagesize();
209
210 rb_fd = bpf_map__fd(skel->maps.user_ringbuf);
211
212 ASSERT_EQ(skel->bss->read, 0, "num_samples_before_bad_sample");
213
214 /* Map the producer_pos as RW. */
215 producer_pos_ptr = mmap(NULL, page_size, PROT_READ | PROT_WRITE,
216 MAP_SHARED, rb_fd, page_size);
217 ASSERT_OK_PTR(producer_pos_ptr, "producer_pos_ptr");
218
219 /* Map the data pages as RW. */
220 data_ptr = mmap(NULL, page_size, PROT_WRITE, MAP_SHARED, rb_fd, 2 * page_size);
221 ASSERT_OK_PTR(data_ptr, "rw_data");
222
223 memset(data_ptr, 0, BPF_RINGBUF_HDR_SZ);
224 *(__u32 *)data_ptr = size;
225
226 /* Synchronizes with smp_load_acquire() in __bpf_user_ringbuf_peek() in the kernel. */
227 smp_store_release(producer_pos_ptr, producer_pos + BPF_RINGBUF_HDR_SZ);
228
229 drain_current_samples();
230 ASSERT_EQ(skel->bss->read, 0, "num_samples_after_bad_sample");
231 ASSERT_EQ(skel->bss->err, err, "err_after_bad_sample");
232
233 ASSERT_OK(munmap(producer_pos_ptr, page_size), "unmap_producer_pos");
234 ASSERT_OK(munmap(data_ptr, page_size), "unmap_data_ptr");
235}
236
237static void test_user_ringbuf_post_misaligned(void)
238{
239 struct user_ringbuf_success *skel;
240 struct user_ring_buffer *ringbuf;
241 int err;
242 __u32 size = (1 << 5) + 7;
243
244 err = load_skel_create_user_ringbuf(&skel, &ringbuf);
245 if (!ASSERT_OK(err, "misaligned_skel"))
246 return;
247
248 manually_write_test_invalid_sample(skel, size, size, -EINVAL);
249 user_ring_buffer__free(ringbuf);
250 user_ringbuf_success__destroy(skel);
251}
252
253static void test_user_ringbuf_post_producer_wrong_offset(void)
254{
255 struct user_ringbuf_success *skel;
256 struct user_ring_buffer *ringbuf;
257 int err;
258 __u32 size = (1 << 5);
259
260 err = load_skel_create_user_ringbuf(&skel, &ringbuf);
261 if (!ASSERT_OK(err, "wrong_offset_skel"))
262 return;
263
264 manually_write_test_invalid_sample(skel, size, size - 8, -EINVAL);
265 user_ring_buffer__free(ringbuf);
266 user_ringbuf_success__destroy(skel);
267}
268
269static void test_user_ringbuf_post_larger_than_ringbuf_sz(void)
270{
271 struct user_ringbuf_success *skel;
272 struct user_ring_buffer *ringbuf;
273 int err;
274 __u32 size = c_ringbuf_size;
275
276 err = load_skel_create_user_ringbuf(&skel, &ringbuf);
277 if (!ASSERT_OK(err, "huge_sample_skel"))
278 return;
279
280 manually_write_test_invalid_sample(skel, size, size, -E2BIG);
281 user_ring_buffer__free(ringbuf);
282 user_ringbuf_success__destroy(skel);
283}
284
285static void test_user_ringbuf_basic(void)
286{
287 struct user_ringbuf_success *skel;
288 struct user_ring_buffer *ringbuf;
289 int err;
290
291 err = load_skel_create_user_ringbuf(&skel, &ringbuf);
292 if (!ASSERT_OK(err, "ringbuf_basic_skel"))
293 return;
294
295 ASSERT_EQ(skel->bss->read, 0, "num_samples_read_before");
296
297 err = write_samples(ringbuf, 2);
298 if (!ASSERT_OK(err, "write_samples"))
299 goto cleanup;
300
301 ASSERT_EQ(skel->bss->read, 2, "num_samples_read_after");
302
303cleanup:
304 user_ring_buffer__free(ringbuf);
305 user_ringbuf_success__destroy(skel);
306}
307
308static void test_user_ringbuf_sample_full_ring_buffer(void)
309{
310 struct user_ringbuf_success *skel;
311 struct user_ring_buffer *ringbuf;
312 int err;
313 void *sample;
314
315 err = load_skel_create_user_ringbuf(&skel, &ringbuf);
316 if (!ASSERT_OK(err, "ringbuf_full_sample_skel"))
317 return;
318
319 sample = user_ring_buffer__reserve(ringbuf, c_ringbuf_size - BPF_RINGBUF_HDR_SZ);
320 if (!ASSERT_OK_PTR(sample, "full_sample"))
321 goto cleanup;
322
323 user_ring_buffer__submit(ringbuf, sample);
324 ASSERT_EQ(skel->bss->read, 0, "num_samples_read_before");
325 drain_current_samples();
326 ASSERT_EQ(skel->bss->read, 1, "num_samples_read_after");
327
328cleanup:
329 user_ring_buffer__free(ringbuf);
330 user_ringbuf_success__destroy(skel);
331}
332
333static void test_user_ringbuf_post_alignment_autoadjust(void)
334{
335 struct user_ringbuf_success *skel;
336 struct user_ring_buffer *ringbuf;
337 struct sample *sample;
338 int err;
339
340 err = load_skel_create_user_ringbuf(&skel, &ringbuf);
341 if (!ASSERT_OK(err, "ringbuf_align_autoadjust_skel"))
342 return;
343
344 /* libbpf should automatically round any sample up to an 8-byte alignment. */
345 sample = user_ring_buffer__reserve(ringbuf, sizeof(*sample) + 1);
346 ASSERT_OK_PTR(sample, "reserve_autoaligned");
347 user_ring_buffer__submit(ringbuf, sample);
348
349 ASSERT_EQ(skel->bss->read, 0, "num_samples_read_before");
350 drain_current_samples();
351 ASSERT_EQ(skel->bss->read, 1, "num_samples_read_after");
352
353 user_ring_buffer__free(ringbuf);
354 user_ringbuf_success__destroy(skel);
355}
356
357static void test_user_ringbuf_overfill(void)
358{
359 struct user_ringbuf_success *skel;
360 struct user_ring_buffer *ringbuf;
361 int err;
362
363 err = load_skel_create_user_ringbuf(&skel, &ringbuf);
364 if (err)
365 return;
366
367 err = write_samples(ringbuf, c_max_entries * 5);
368 ASSERT_ERR(err, "write_samples");
369 ASSERT_EQ(skel->bss->read, c_max_entries, "max_entries");
370
371 user_ring_buffer__free(ringbuf);
372 user_ringbuf_success__destroy(skel);
373}
374
375static void test_user_ringbuf_discards_properly_ignored(void)
376{
377 struct user_ringbuf_success *skel;
378 struct user_ring_buffer *ringbuf;
379 int err, num_discarded = 0;
380 __u64 *token;
381
382 err = load_skel_create_user_ringbuf(&skel, &ringbuf);
383 if (err)
384 return;
385
386 ASSERT_EQ(skel->bss->read, 0, "num_samples_read_before");
387
388 while (1) {
389 /* Write samples until the buffer is full. */
390 token = user_ring_buffer__reserve(ringbuf, sizeof(*token));
391 if (!token)
392 break;
393
394 user_ring_buffer__discard(ringbuf, token);
395 num_discarded++;
396 }
397
398 if (!ASSERT_GE(num_discarded, 0, "num_discarded"))
399 goto cleanup;
400
401 /* Should not read any samples, as they are all discarded. */
402 ASSERT_EQ(skel->bss->read, 0, "num_pre_kick");
403 drain_current_samples();
404 ASSERT_EQ(skel->bss->read, 0, "num_post_kick");
405
406 /* Now that the ring buffer has been drained, we should be able to
407 * reserve another token.
408 */
409 token = user_ring_buffer__reserve(ringbuf, sizeof(*token));
410
411 if (!ASSERT_OK_PTR(token, "new_token"))
412 goto cleanup;
413
414 user_ring_buffer__discard(ringbuf, token);
415cleanup:
416 user_ring_buffer__free(ringbuf);
417 user_ringbuf_success__destroy(skel);
418}
419
420static void test_user_ringbuf_loop(void)
421{
422 struct user_ringbuf_success *skel;
423 struct user_ring_buffer *ringbuf;
424 uint32_t total_samples = 8192;
425 uint32_t remaining_samples = total_samples;
426 int err;
427
428 BUILD_BUG_ON(total_samples <= c_max_entries);
429 err = load_skel_create_user_ringbuf(&skel, &ringbuf);
430 if (err)
431 return;
432
433 do {
434 uint32_t curr_samples;
435
436 curr_samples = remaining_samples > c_max_entries
437 ? c_max_entries : remaining_samples;
438 err = write_samples(ringbuf, curr_samples);
439 if (err != 0) {
440 /* Assert inside of if statement to avoid flooding logs
441 * on the success path.
442 */
443 ASSERT_OK(err, "write_samples");
444 goto cleanup;
445 }
446
447 remaining_samples -= curr_samples;
448 ASSERT_EQ(skel->bss->read, total_samples - remaining_samples,
449 "current_batched_entries");
450 } while (remaining_samples > 0);
451 ASSERT_EQ(skel->bss->read, total_samples, "total_batched_entries");
452
453cleanup:
454 user_ring_buffer__free(ringbuf);
455 user_ringbuf_success__destroy(skel);
456}
457
458static int send_test_message(struct user_ring_buffer *ringbuf,
459 enum test_msg_op op, s64 operand_64,
460 s32 operand_32)
461{
462 struct test_msg *msg;
463
464 msg = user_ring_buffer__reserve(ringbuf, sizeof(*msg));
465 if (!msg) {
466 /* Assert on the error path to avoid spamming logs with mostly
467 * success messages.
468 */
469 ASSERT_OK_PTR(msg, "reserve_msg");
470 return -ENOMEM;
471 }
472
473 msg->msg_op = op;
474
475 switch (op) {
476 case TEST_MSG_OP_INC64:
477 case TEST_MSG_OP_MUL64:
478 msg->operand_64 = operand_64;
479 break;
480 case TEST_MSG_OP_INC32:
481 case TEST_MSG_OP_MUL32:
482 msg->operand_32 = operand_32;
483 break;
484 default:
485 PRINT_FAIL("Invalid operand %d\n", op);
486 user_ring_buffer__discard(ringbuf, msg);
487 return -EINVAL;
488 }
489
490 user_ring_buffer__submit(ringbuf, msg);
491
492 return 0;
493}
494
495static void kick_kernel_read_messages(void)
496{
497 syscall(__NR_prctl);
498}
499
500static int handle_kernel_msg(void *ctx, void *data, size_t len)
501{
502 struct user_ringbuf_success *skel = ctx;
503 struct test_msg *msg = data;
504
505 switch (msg->msg_op) {
506 case TEST_MSG_OP_INC64:
507 skel->bss->user_mutated += msg->operand_64;
508 return 0;
509 case TEST_MSG_OP_INC32:
510 skel->bss->user_mutated += msg->operand_32;
511 return 0;
512 case TEST_MSG_OP_MUL64:
513 skel->bss->user_mutated *= msg->operand_64;
514 return 0;
515 case TEST_MSG_OP_MUL32:
516 skel->bss->user_mutated *= msg->operand_32;
517 return 0;
518 default:
519 fprintf(stderr, "Invalid operand %d\n", msg->msg_op);
520 return -EINVAL;
521 }
522}
523
524static void drain_kernel_messages_buffer(struct ring_buffer *kern_ringbuf,
525 struct user_ringbuf_success *skel)
526{
527 int cnt;
528
529 cnt = ring_buffer__consume(kern_ringbuf);
530 ASSERT_EQ(cnt, 8, "consume_kern_ringbuf");
531 ASSERT_OK(skel->bss->err, "consume_kern_ringbuf_err");
532}
533
534static void test_user_ringbuf_msg_protocol(void)
535{
536 struct user_ringbuf_success *skel;
537 struct user_ring_buffer *user_ringbuf;
538 struct ring_buffer *kern_ringbuf;
539 int err, i;
540 __u64 expected_kern = 0;
541
542 err = load_skel_create_ringbufs(&skel, &kern_ringbuf, handle_kernel_msg, &user_ringbuf);
543 if (!ASSERT_OK(err, "create_ringbufs"))
544 return;
545
546 for (i = 0; i < 64; i++) {
547 enum test_msg_op op = i % TEST_MSG_OP_NUM_OPS;
548 __u64 operand_64 = TEST_OP_64;
549 __u32 operand_32 = TEST_OP_32;
550
551 err = send_test_message(user_ringbuf, op, operand_64, operand_32);
552 if (err) {
553 /* Only assert on a failure to avoid spamming success logs. */
554 ASSERT_OK(err, "send_test_message");
555 goto cleanup;
556 }
557
558 switch (op) {
559 case TEST_MSG_OP_INC64:
560 expected_kern += operand_64;
561 break;
562 case TEST_MSG_OP_INC32:
563 expected_kern += operand_32;
564 break;
565 case TEST_MSG_OP_MUL64:
566 expected_kern *= operand_64;
567 break;
568 case TEST_MSG_OP_MUL32:
569 expected_kern *= operand_32;
570 break;
571 default:
572 PRINT_FAIL("Unexpected op %d\n", op);
573 goto cleanup;
574 }
575
576 if (i % 8 == 0) {
577 kick_kernel_read_messages();
578 ASSERT_EQ(skel->bss->kern_mutated, expected_kern, "expected_kern");
579 ASSERT_EQ(skel->bss->err, 0, "bpf_prog_err");
580 drain_kernel_messages_buffer(kern_ringbuf, skel);
581 }
582 }
583
584cleanup:
585 ring_buffer__free(kern_ringbuf);
586 user_ring_buffer__free(user_ringbuf);
587 user_ringbuf_success__destroy(skel);
588}
589
590static void *kick_kernel_cb(void *arg)
591{
592 /* Kick the kernel, causing it to drain the ring buffer and then wake
593 * up the test thread waiting on epoll.
594 */
595 syscall(__NR_getrlimit);
596
597 return NULL;
598}
599
600static int spawn_kick_thread_for_poll(void)
601{
602 pthread_t thread;
603
604 return pthread_create(&thread, NULL, kick_kernel_cb, NULL);
605}
606
607static void test_user_ringbuf_blocking_reserve(void)
608{
609 struct user_ringbuf_success *skel;
610 struct user_ring_buffer *ringbuf;
611 int err, num_written = 0;
612 __u64 *token;
613
614 err = load_skel_create_user_ringbuf(&skel, &ringbuf);
615 if (err)
616 return;
617
618 ASSERT_EQ(skel->bss->read, 0, "num_samples_read_before");
619
620 while (1) {
621 /* Write samples until the buffer is full. */
622 token = user_ring_buffer__reserve(ringbuf, sizeof(*token));
623 if (!token)
624 break;
625
626 *token = 0xdeadbeef;
627
628 user_ring_buffer__submit(ringbuf, token);
629 num_written++;
630 }
631
632 if (!ASSERT_GE(num_written, 0, "num_written"))
633 goto cleanup;
634
635 /* Should not have read any samples until the kernel is kicked. */
636 ASSERT_EQ(skel->bss->read, 0, "num_pre_kick");
637
638 /* We correctly time out after 1 second, without a sample. */
639 token = user_ring_buffer__reserve_blocking(ringbuf, sizeof(*token), 1000);
640 if (!ASSERT_EQ(token, NULL, "pre_kick_timeout_token"))
641 goto cleanup;
642
643 err = spawn_kick_thread_for_poll();
644 if (!ASSERT_EQ(err, 0, "deferred_kick_thread\n"))
645 goto cleanup;
646
647 /* After spawning another thread that asychronously kicks the kernel to
648 * drain the messages, we're able to block and successfully get a
649 * sample once we receive an event notification.
650 */
651 token = user_ring_buffer__reserve_blocking(ringbuf, sizeof(*token), 10000);
652
653 if (!ASSERT_OK_PTR(token, "block_token"))
654 goto cleanup;
655
656 ASSERT_GT(skel->bss->read, 0, "num_post_kill");
657 ASSERT_LE(skel->bss->read, num_written, "num_post_kill");
658 ASSERT_EQ(skel->bss->err, 0, "err_post_poll");
659 user_ring_buffer__discard(ringbuf, token);
660
661cleanup:
662 user_ring_buffer__free(ringbuf);
663 user_ringbuf_success__destroy(skel);
664}
665
666static struct {
667 const char *prog_name;
668 const char *expected_err_msg;
669} failure_tests[] = {
670 /* failure cases */
671 {"user_ringbuf_callback_bad_access1", "negative offset dynptr_ptr ptr"},
672 {"user_ringbuf_callback_bad_access2", "dereference of modified dynptr_ptr ptr"},
673 {"user_ringbuf_callback_write_forbidden", "invalid mem access 'dynptr_ptr'"},
674 {"user_ringbuf_callback_null_context_write", "invalid mem access 'scalar'"},
675 {"user_ringbuf_callback_null_context_read", "invalid mem access 'scalar'"},
676 {"user_ringbuf_callback_discard_dynptr", "cannot release unowned const bpf_dynptr"},
677 {"user_ringbuf_callback_submit_dynptr", "cannot release unowned const bpf_dynptr"},
678 {"user_ringbuf_callback_invalid_return", "At callback return the register R0 has value"},
679 {"user_ringbuf_callback_reinit_dynptr_mem", "Dynptr has to be an uninitialized dynptr"},
680 {"user_ringbuf_callback_reinit_dynptr_ringbuf", "Dynptr has to be an uninitialized dynptr"},
681};
682
683#define SUCCESS_TEST(_func) { _func, #_func }
684
685static struct {
686 void (*test_callback)(void);
687 const char *test_name;
688} success_tests[] = {
689 SUCCESS_TEST(test_user_ringbuf_mappings),
690 SUCCESS_TEST(test_user_ringbuf_post_misaligned),
691 SUCCESS_TEST(test_user_ringbuf_post_producer_wrong_offset),
692 SUCCESS_TEST(test_user_ringbuf_post_larger_than_ringbuf_sz),
693 SUCCESS_TEST(test_user_ringbuf_basic),
694 SUCCESS_TEST(test_user_ringbuf_sample_full_ring_buffer),
695 SUCCESS_TEST(test_user_ringbuf_post_alignment_autoadjust),
696 SUCCESS_TEST(test_user_ringbuf_overfill),
697 SUCCESS_TEST(test_user_ringbuf_discards_properly_ignored),
698 SUCCESS_TEST(test_user_ringbuf_loop),
699 SUCCESS_TEST(test_user_ringbuf_msg_protocol),
700 SUCCESS_TEST(test_user_ringbuf_blocking_reserve),
701};
702
703static void verify_fail(const char *prog_name, const char *expected_err_msg)
704{
705 LIBBPF_OPTS(bpf_object_open_opts, opts);
706 struct bpf_program *prog;
707 struct user_ringbuf_fail *skel;
708 int err;
709
710 opts.kernel_log_buf = obj_log_buf;
711 opts.kernel_log_size = log_buf_sz;
712 opts.kernel_log_level = 1;
713
714 skel = user_ringbuf_fail__open_opts(&opts);
715 if (!ASSERT_OK_PTR(skel, "dynptr_fail__open_opts"))
716 goto cleanup;
717
718 prog = bpf_object__find_program_by_name(skel->obj, prog_name);
719 if (!ASSERT_OK_PTR(prog, "bpf_object__find_program_by_name"))
720 goto cleanup;
721
722 bpf_program__set_autoload(prog, true);
723
724 bpf_map__set_max_entries(skel->maps.user_ringbuf, getpagesize());
725
726 err = user_ringbuf_fail__load(skel);
727 if (!ASSERT_ERR(err, "unexpected load success"))
728 goto cleanup;
729
730 if (!ASSERT_OK_PTR(strstr(obj_log_buf, expected_err_msg), "expected_err_msg")) {
731 fprintf(stderr, "Expected err_msg: %s\n", expected_err_msg);
732 fprintf(stderr, "Verifier output: %s\n", obj_log_buf);
733 }
734
735cleanup:
736 user_ringbuf_fail__destroy(skel);
737}
738
739void test_user_ringbuf(void)
740{
741 int i;
742
743 for (i = 0; i < ARRAY_SIZE(success_tests); i++) {
744 if (!test__start_subtest(success_tests[i].test_name))
745 continue;
746
747 success_tests[i].test_callback();
748 }
749
750 for (i = 0; i < ARRAY_SIZE(failure_tests); i++) {
751 if (!test__start_subtest(failure_tests[i].prog_name))
752 continue;
753
754 verify_fail(failure_tests[i].prog_name, failure_tests[i].expected_err_msg);
755 }
756}