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v6.13.7
  1// SPDX-License-Identifier: GPL-2.0
  2/* Copyright (c) 2022 Facebook */
  3
  4#include <string.h>
  5#include <stdbool.h>
  6#include <linux/bpf.h>
  7#include <bpf/bpf_helpers.h>
  8#include <bpf/bpf_tracing.h>
  9#include "bpf_misc.h"
 10#include "bpf_kfuncs.h"
 11#include "errno.h"
 12
 13char _license[] SEC("license") = "GPL";
 14
 15int pid, err, val;
 16
 17struct sample {
 18	int pid;
 19	int seq;
 20	long value;
 21	char comm[16];
 22};
 23
 24struct {
 25	__uint(type, BPF_MAP_TYPE_RINGBUF);
 26	__uint(max_entries, 4096);
 27} ringbuf SEC(".maps");
 28
 29struct {
 30	__uint(type, BPF_MAP_TYPE_ARRAY);
 31	__uint(max_entries, 1);
 32	__type(key, __u32);
 33	__type(value, __u32);
 34} array_map SEC(".maps");
 35
 36SEC("?tp/syscalls/sys_enter_nanosleep")
 37int test_read_write(void *ctx)
 38{
 39	char write_data[64] = "hello there, world!!";
 40	char read_data[64] = {};
 41	struct bpf_dynptr ptr;
 42	int i;
 43
 44	if (bpf_get_current_pid_tgid() >> 32 != pid)
 45		return 0;
 46
 47	bpf_ringbuf_reserve_dynptr(&ringbuf, sizeof(write_data), 0, &ptr);
 48
 49	/* Write data into the dynptr */
 50	err = bpf_dynptr_write(&ptr, 0, write_data, sizeof(write_data), 0);
 51
 52	/* Read the data that was written into the dynptr */
 53	err = err ?: bpf_dynptr_read(read_data, sizeof(read_data), &ptr, 0, 0);
 54
 55	/* Ensure the data we read matches the data we wrote */
 56	for (i = 0; i < sizeof(read_data); i++) {
 57		if (read_data[i] != write_data[i]) {
 58			err = 1;
 59			break;
 60		}
 61	}
 62
 63	bpf_ringbuf_discard_dynptr(&ptr, 0);
 64	return 0;
 65}
 66
 67SEC("?tp/syscalls/sys_enter_nanosleep")
 68int test_dynptr_data(void *ctx)
 69{
 70	__u32 key = 0, val = 235, *map_val;
 71	struct bpf_dynptr ptr;
 72	__u32 map_val_size;
 73	void *data;
 74
 75	map_val_size = sizeof(*map_val);
 76
 77	if (bpf_get_current_pid_tgid() >> 32 != pid)
 78		return 0;
 79
 80	bpf_map_update_elem(&array_map, &key, &val, 0);
 81
 82	map_val = bpf_map_lookup_elem(&array_map, &key);
 83	if (!map_val) {
 84		err = 1;
 85		return 0;
 86	}
 87
 88	bpf_dynptr_from_mem(map_val, map_val_size, 0, &ptr);
 89
 90	/* Try getting a data slice that is out of range */
 91	data = bpf_dynptr_data(&ptr, map_val_size + 1, 1);
 92	if (data) {
 93		err = 2;
 94		return 0;
 95	}
 96
 97	/* Try getting more bytes than available */
 98	data = bpf_dynptr_data(&ptr, 0, map_val_size + 1);
 99	if (data) {
100		err = 3;
101		return 0;
102	}
103
104	data = bpf_dynptr_data(&ptr, 0, sizeof(__u32));
105	if (!data) {
106		err = 4;
107		return 0;
108	}
109
110	*(__u32 *)data = 999;
111
112	err = bpf_probe_read_kernel(&val, sizeof(val), data);
113	if (err)
114		return 0;
115
116	if (val != *(int *)data)
117		err = 5;
118
119	return 0;
120}
121
122static int ringbuf_callback(__u32 index, void *data)
123{
124	struct sample *sample;
125
126	struct bpf_dynptr *ptr = (struct bpf_dynptr *)data;
127
128	sample = bpf_dynptr_data(ptr, 0, sizeof(*sample));
129	if (!sample)
130		err = 2;
131	else
132		sample->pid += index;
133
134	return 0;
135}
136
137SEC("?tp/syscalls/sys_enter_nanosleep")
138int test_ringbuf(void *ctx)
139{
140	struct bpf_dynptr ptr;
141	struct sample *sample;
142
143	if (bpf_get_current_pid_tgid() >> 32 != pid)
144		return 0;
145
146	val = 100;
147
148	/* check that you can reserve a dynamic size reservation */
149	err = bpf_ringbuf_reserve_dynptr(&ringbuf, val, 0, &ptr);
150
151	sample = err ? NULL : bpf_dynptr_data(&ptr, 0, sizeof(*sample));
152	if (!sample) {
153		err = 1;
154		goto done;
155	}
156
157	sample->pid = 10;
158
159	/* Can pass dynptr to callback functions */
160	bpf_loop(10, ringbuf_callback, &ptr, 0);
161
162	if (sample->pid != 55)
163		err = 2;
164
165done:
166	bpf_ringbuf_discard_dynptr(&ptr, 0);
167	return 0;
168}
169
170SEC("?cgroup_skb/egress")
171int test_skb_readonly(struct __sk_buff *skb)
172{
173	__u8 write_data[2] = {1, 2};
174	struct bpf_dynptr ptr;
175	int ret;
176
177	if (bpf_dynptr_from_skb(skb, 0, &ptr)) {
178		err = 1;
179		return 1;
180	}
181
182	/* since cgroup skbs are read only, writes should fail */
183	ret = bpf_dynptr_write(&ptr, 0, write_data, sizeof(write_data), 0);
184	if (ret != -EINVAL) {
185		err = 2;
186		return 1;
187	}
188
189	return 1;
190}
191
192SEC("?cgroup_skb/egress")
193int test_dynptr_skb_data(struct __sk_buff *skb)
194{
195	struct bpf_dynptr ptr;
196	__u64 *data;
197
198	if (bpf_dynptr_from_skb(skb, 0, &ptr)) {
199		err = 1;
200		return 1;
201	}
202
203	/* This should return NULL. Must use bpf_dynptr_slice API */
204	data = bpf_dynptr_data(&ptr, 0, 1);
205	if (data) {
206		err = 2;
207		return 1;
208	}
209
210	return 1;
211}
212
213SEC("tp/syscalls/sys_enter_nanosleep")
214int test_adjust(void *ctx)
215{
216	struct bpf_dynptr ptr;
217	__u32 bytes = 64;
218	__u32 off = 10;
219	__u32 trim = 15;
220
221	if (bpf_get_current_pid_tgid() >> 32 != pid)
222		return 0;
223
224	err = bpf_ringbuf_reserve_dynptr(&ringbuf, bytes, 0, &ptr);
225	if (err) {
226		err = 1;
227		goto done;
228	}
229
230	if (bpf_dynptr_size(&ptr) != bytes) {
231		err = 2;
232		goto done;
233	}
234
235	/* Advance the dynptr by off */
236	err = bpf_dynptr_adjust(&ptr, off, bpf_dynptr_size(&ptr));
237	if (err) {
238		err = 3;
239		goto done;
240	}
241
242	if (bpf_dynptr_size(&ptr) != bytes - off) {
243		err = 4;
244		goto done;
245	}
246
247	/* Trim the dynptr */
248	err = bpf_dynptr_adjust(&ptr, off, 15);
249	if (err) {
250		err = 5;
251		goto done;
252	}
253
254	/* Check that the size was adjusted correctly */
255	if (bpf_dynptr_size(&ptr) != trim - off) {
256		err = 6;
257		goto done;
258	}
259
260done:
261	bpf_ringbuf_discard_dynptr(&ptr, 0);
262	return 0;
263}
264
265SEC("tp/syscalls/sys_enter_nanosleep")
266int test_adjust_err(void *ctx)
267{
268	char write_data[45] = "hello there, world!!";
269	struct bpf_dynptr ptr;
270	__u32 size = 64;
271	__u32 off = 20;
272
273	if (bpf_get_current_pid_tgid() >> 32 != pid)
274		return 0;
275
276	if (bpf_ringbuf_reserve_dynptr(&ringbuf, size, 0, &ptr)) {
277		err = 1;
278		goto done;
279	}
280
281	/* Check that start can't be greater than end */
282	if (bpf_dynptr_adjust(&ptr, 5, 1) != -EINVAL) {
283		err = 2;
284		goto done;
285	}
286
287	/* Check that start can't be greater than size */
288	if (bpf_dynptr_adjust(&ptr, size + 1, size + 1) != -ERANGE) {
289		err = 3;
290		goto done;
291	}
292
293	/* Check that end can't be greater than size */
294	if (bpf_dynptr_adjust(&ptr, 0, size + 1) != -ERANGE) {
295		err = 4;
296		goto done;
297	}
298
299	if (bpf_dynptr_adjust(&ptr, off, size)) {
300		err = 5;
301		goto done;
302	}
303
304	/* Check that you can't write more bytes than available into the dynptr
305	 * after you've adjusted it
306	 */
307	if (bpf_dynptr_write(&ptr, 0, &write_data, sizeof(write_data), 0) != -E2BIG) {
308		err = 6;
309		goto done;
310	}
311
312	/* Check that even after adjusting, submitting/discarding
313	 * a ringbuf dynptr works
314	 */
315	bpf_ringbuf_submit_dynptr(&ptr, 0);
316	return 0;
317
318done:
319	bpf_ringbuf_discard_dynptr(&ptr, 0);
320	return 0;
321}
322
323SEC("tp/syscalls/sys_enter_nanosleep")
324int test_zero_size_dynptr(void *ctx)
325{
326	char write_data = 'x', read_data;
327	struct bpf_dynptr ptr;
328	__u32 size = 64;
329
330	if (bpf_get_current_pid_tgid() >> 32 != pid)
331		return 0;
332
333	if (bpf_ringbuf_reserve_dynptr(&ringbuf, size, 0, &ptr)) {
334		err = 1;
335		goto done;
336	}
337
338	/* After this, the dynptr has a size of 0 */
339	if (bpf_dynptr_adjust(&ptr, size, size)) {
340		err = 2;
341		goto done;
342	}
343
344	/* Test that reading + writing non-zero bytes is not ok */
345	if (bpf_dynptr_read(&read_data, sizeof(read_data), &ptr, 0, 0) != -E2BIG) {
346		err = 3;
347		goto done;
348	}
349
350	if (bpf_dynptr_write(&ptr, 0, &write_data, sizeof(write_data), 0) != -E2BIG) {
351		err = 4;
352		goto done;
353	}
354
355	/* Test that reading + writing 0 bytes from a 0-size dynptr is ok */
356	if (bpf_dynptr_read(&read_data, 0, &ptr, 0, 0)) {
357		err = 5;
358		goto done;
359	}
360
361	if (bpf_dynptr_write(&ptr, 0, &write_data, 0, 0)) {
362		err = 6;
363		goto done;
364	}
365
366	err = 0;
367
368done:
369	bpf_ringbuf_discard_dynptr(&ptr, 0);
370	return 0;
371}
372
373SEC("tp/syscalls/sys_enter_nanosleep")
374int test_dynptr_is_null(void *ctx)
375{
376	struct bpf_dynptr ptr1;
377	struct bpf_dynptr ptr2;
378	__u64 size = 4;
379
380	if (bpf_get_current_pid_tgid() >> 32 != pid)
381		return 0;
382
383	/* Pass in invalid flags, get back an invalid dynptr */
384	if (bpf_ringbuf_reserve_dynptr(&ringbuf, size, 123, &ptr1) != -EINVAL) {
385		err = 1;
386		goto exit_early;
387	}
388
389	/* Test that the invalid dynptr is null */
390	if (!bpf_dynptr_is_null(&ptr1)) {
391		err = 2;
392		goto exit_early;
393	}
394
395	/* Get a valid dynptr */
396	if (bpf_ringbuf_reserve_dynptr(&ringbuf, size, 0, &ptr2)) {
397		err = 3;
398		goto exit;
399	}
400
401	/* Test that the valid dynptr is not null */
402	if (bpf_dynptr_is_null(&ptr2)) {
403		err = 4;
404		goto exit;
405	}
406
407exit:
408	bpf_ringbuf_discard_dynptr(&ptr2, 0);
409exit_early:
410	bpf_ringbuf_discard_dynptr(&ptr1, 0);
411	return 0;
412}
413
414SEC("cgroup_skb/egress")
415int test_dynptr_is_rdonly(struct __sk_buff *skb)
416{
417	struct bpf_dynptr ptr1;
418	struct bpf_dynptr ptr2;
419	struct bpf_dynptr ptr3;
420
421	/* Pass in invalid flags, get back an invalid dynptr */
422	if (bpf_dynptr_from_skb(skb, 123, &ptr1) != -EINVAL) {
423		err = 1;
424		return 0;
425	}
426
427	/* Test that an invalid dynptr is_rdonly returns false */
428	if (bpf_dynptr_is_rdonly(&ptr1)) {
429		err = 2;
430		return 0;
431	}
432
433	/* Get a read-only dynptr */
434	if (bpf_dynptr_from_skb(skb, 0, &ptr2)) {
435		err = 3;
436		return 0;
437	}
438
439	/* Test that the dynptr is read-only */
440	if (!bpf_dynptr_is_rdonly(&ptr2)) {
441		err = 4;
442		return 0;
443	}
444
445	/* Get a read-writeable dynptr */
446	if (bpf_ringbuf_reserve_dynptr(&ringbuf, 64, 0, &ptr3)) {
447		err = 5;
448		goto done;
449	}
450
451	/* Test that the dynptr is read-only */
452	if (bpf_dynptr_is_rdonly(&ptr3)) {
453		err = 6;
454		goto done;
455	}
456
457done:
458	bpf_ringbuf_discard_dynptr(&ptr3, 0);
459	return 0;
460}
461
462SEC("cgroup_skb/egress")
463int test_dynptr_clone(struct __sk_buff *skb)
464{
465	struct bpf_dynptr ptr1;
466	struct bpf_dynptr ptr2;
467	__u32 off = 2, size;
468
469	/* Get a dynptr */
470	if (bpf_dynptr_from_skb(skb, 0, &ptr1)) {
471		err = 1;
472		return 0;
473	}
474
475	if (bpf_dynptr_adjust(&ptr1, off, bpf_dynptr_size(&ptr1))) {
476		err = 2;
477		return 0;
478	}
479
480	/* Clone the dynptr */
481	if (bpf_dynptr_clone(&ptr1, &ptr2)) {
482		err = 3;
483		return 0;
484	}
485
486	size = bpf_dynptr_size(&ptr1);
487
488	/* Check that the clone has the same size and rd-only */
489	if (bpf_dynptr_size(&ptr2) != size) {
490		err = 4;
491		return 0;
492	}
493
494	if (bpf_dynptr_is_rdonly(&ptr2) != bpf_dynptr_is_rdonly(&ptr1)) {
495		err = 5;
496		return 0;
497	}
498
499	/* Advance and trim the original dynptr */
500	bpf_dynptr_adjust(&ptr1, 5, 5);
501
502	/* Check that only original dynptr was affected, and the clone wasn't */
503	if (bpf_dynptr_size(&ptr2) != size) {
504		err = 6;
505		return 0;
506	}
507
508	return 0;
509}
510
511SEC("?cgroup_skb/egress")
512int test_dynptr_skb_no_buff(struct __sk_buff *skb)
513{
514	struct bpf_dynptr ptr;
515	__u64 *data;
516
517	if (bpf_dynptr_from_skb(skb, 0, &ptr)) {
518		err = 1;
519		return 1;
520	}
521
522	/* This may return NULL. SKB may require a buffer */
523	data = bpf_dynptr_slice(&ptr, 0, NULL, 1);
524
525	return !!data;
526}
527
528SEC("?cgroup_skb/egress")
529int test_dynptr_skb_strcmp(struct __sk_buff *skb)
530{
531	struct bpf_dynptr ptr;
532	char *data;
533
534	if (bpf_dynptr_from_skb(skb, 0, &ptr)) {
535		err = 1;
536		return 1;
537	}
538
539	/* This may return NULL. SKB may require a buffer */
540	data = bpf_dynptr_slice(&ptr, 0, NULL, 10);
541	if (data) {
542		bpf_strncmp(data, 10, "foo");
543		return 1;
544	}
545
546	return 1;
547}
548
549SEC("tp_btf/kfree_skb")
550int BPF_PROG(test_dynptr_skb_tp_btf, void *skb, void *location)
551{
552	__u8 write_data[2] = {1, 2};
553	struct bpf_dynptr ptr;
554	int ret;
555
556	if (bpf_dynptr_from_skb(skb, 0, &ptr)) {
557		err = 1;
558		return 1;
559	}
560
561	/* since tp_btf skbs are read only, writes should fail */
562	ret = bpf_dynptr_write(&ptr, 0, write_data, sizeof(write_data), 0);
563	if (ret != -EINVAL) {
564		err = 2;
565		return 1;
566	}
567
568	return 1;
569}
v6.8
  1// SPDX-License-Identifier: GPL-2.0
  2/* Copyright (c) 2022 Facebook */
  3
  4#include <string.h>
  5#include <stdbool.h>
  6#include <linux/bpf.h>
  7#include <bpf/bpf_helpers.h>
 
  8#include "bpf_misc.h"
  9#include "bpf_kfuncs.h"
 10#include "errno.h"
 11
 12char _license[] SEC("license") = "GPL";
 13
 14int pid, err, val;
 15
 16struct sample {
 17	int pid;
 18	int seq;
 19	long value;
 20	char comm[16];
 21};
 22
 23struct {
 24	__uint(type, BPF_MAP_TYPE_RINGBUF);
 25	__uint(max_entries, 4096);
 26} ringbuf SEC(".maps");
 27
 28struct {
 29	__uint(type, BPF_MAP_TYPE_ARRAY);
 30	__uint(max_entries, 1);
 31	__type(key, __u32);
 32	__type(value, __u32);
 33} array_map SEC(".maps");
 34
 35SEC("?tp/syscalls/sys_enter_nanosleep")
 36int test_read_write(void *ctx)
 37{
 38	char write_data[64] = "hello there, world!!";
 39	char read_data[64] = {};
 40	struct bpf_dynptr ptr;
 41	int i;
 42
 43	if (bpf_get_current_pid_tgid() >> 32 != pid)
 44		return 0;
 45
 46	bpf_ringbuf_reserve_dynptr(&ringbuf, sizeof(write_data), 0, &ptr);
 47
 48	/* Write data into the dynptr */
 49	err = bpf_dynptr_write(&ptr, 0, write_data, sizeof(write_data), 0);
 50
 51	/* Read the data that was written into the dynptr */
 52	err = err ?: bpf_dynptr_read(read_data, sizeof(read_data), &ptr, 0, 0);
 53
 54	/* Ensure the data we read matches the data we wrote */
 55	for (i = 0; i < sizeof(read_data); i++) {
 56		if (read_data[i] != write_data[i]) {
 57			err = 1;
 58			break;
 59		}
 60	}
 61
 62	bpf_ringbuf_discard_dynptr(&ptr, 0);
 63	return 0;
 64}
 65
 66SEC("?tp/syscalls/sys_enter_nanosleep")
 67int test_dynptr_data(void *ctx)
 68{
 69	__u32 key = 0, val = 235, *map_val;
 70	struct bpf_dynptr ptr;
 71	__u32 map_val_size;
 72	void *data;
 73
 74	map_val_size = sizeof(*map_val);
 75
 76	if (bpf_get_current_pid_tgid() >> 32 != pid)
 77		return 0;
 78
 79	bpf_map_update_elem(&array_map, &key, &val, 0);
 80
 81	map_val = bpf_map_lookup_elem(&array_map, &key);
 82	if (!map_val) {
 83		err = 1;
 84		return 0;
 85	}
 86
 87	bpf_dynptr_from_mem(map_val, map_val_size, 0, &ptr);
 88
 89	/* Try getting a data slice that is out of range */
 90	data = bpf_dynptr_data(&ptr, map_val_size + 1, 1);
 91	if (data) {
 92		err = 2;
 93		return 0;
 94	}
 95
 96	/* Try getting more bytes than available */
 97	data = bpf_dynptr_data(&ptr, 0, map_val_size + 1);
 98	if (data) {
 99		err = 3;
100		return 0;
101	}
102
103	data = bpf_dynptr_data(&ptr, 0, sizeof(__u32));
104	if (!data) {
105		err = 4;
106		return 0;
107	}
108
109	*(__u32 *)data = 999;
110
111	err = bpf_probe_read_kernel(&val, sizeof(val), data);
112	if (err)
113		return 0;
114
115	if (val != *(int *)data)
116		err = 5;
117
118	return 0;
119}
120
121static int ringbuf_callback(__u32 index, void *data)
122{
123	struct sample *sample;
124
125	struct bpf_dynptr *ptr = (struct bpf_dynptr *)data;
126
127	sample = bpf_dynptr_data(ptr, 0, sizeof(*sample));
128	if (!sample)
129		err = 2;
130	else
131		sample->pid += index;
132
133	return 0;
134}
135
136SEC("?tp/syscalls/sys_enter_nanosleep")
137int test_ringbuf(void *ctx)
138{
139	struct bpf_dynptr ptr;
140	struct sample *sample;
141
142	if (bpf_get_current_pid_tgid() >> 32 != pid)
143		return 0;
144
145	val = 100;
146
147	/* check that you can reserve a dynamic size reservation */
148	err = bpf_ringbuf_reserve_dynptr(&ringbuf, val, 0, &ptr);
149
150	sample = err ? NULL : bpf_dynptr_data(&ptr, 0, sizeof(*sample));
151	if (!sample) {
152		err = 1;
153		goto done;
154	}
155
156	sample->pid = 10;
157
158	/* Can pass dynptr to callback functions */
159	bpf_loop(10, ringbuf_callback, &ptr, 0);
160
161	if (sample->pid != 55)
162		err = 2;
163
164done:
165	bpf_ringbuf_discard_dynptr(&ptr, 0);
166	return 0;
167}
168
169SEC("?cgroup_skb/egress")
170int test_skb_readonly(struct __sk_buff *skb)
171{
172	__u8 write_data[2] = {1, 2};
173	struct bpf_dynptr ptr;
174	int ret;
175
176	if (bpf_dynptr_from_skb(skb, 0, &ptr)) {
177		err = 1;
178		return 1;
179	}
180
181	/* since cgroup skbs are read only, writes should fail */
182	ret = bpf_dynptr_write(&ptr, 0, write_data, sizeof(write_data), 0);
183	if (ret != -EINVAL) {
184		err = 2;
185		return 1;
186	}
187
188	return 1;
189}
190
191SEC("?cgroup_skb/egress")
192int test_dynptr_skb_data(struct __sk_buff *skb)
193{
194	struct bpf_dynptr ptr;
195	__u64 *data;
196
197	if (bpf_dynptr_from_skb(skb, 0, &ptr)) {
198		err = 1;
199		return 1;
200	}
201
202	/* This should return NULL. Must use bpf_dynptr_slice API */
203	data = bpf_dynptr_data(&ptr, 0, 1);
204	if (data) {
205		err = 2;
206		return 1;
207	}
208
209	return 1;
210}
211
212SEC("tp/syscalls/sys_enter_nanosleep")
213int test_adjust(void *ctx)
214{
215	struct bpf_dynptr ptr;
216	__u32 bytes = 64;
217	__u32 off = 10;
218	__u32 trim = 15;
219
220	if (bpf_get_current_pid_tgid() >> 32 != pid)
221		return 0;
222
223	err = bpf_ringbuf_reserve_dynptr(&ringbuf, bytes, 0, &ptr);
224	if (err) {
225		err = 1;
226		goto done;
227	}
228
229	if (bpf_dynptr_size(&ptr) != bytes) {
230		err = 2;
231		goto done;
232	}
233
234	/* Advance the dynptr by off */
235	err = bpf_dynptr_adjust(&ptr, off, bpf_dynptr_size(&ptr));
236	if (err) {
237		err = 3;
238		goto done;
239	}
240
241	if (bpf_dynptr_size(&ptr) != bytes - off) {
242		err = 4;
243		goto done;
244	}
245
246	/* Trim the dynptr */
247	err = bpf_dynptr_adjust(&ptr, off, 15);
248	if (err) {
249		err = 5;
250		goto done;
251	}
252
253	/* Check that the size was adjusted correctly */
254	if (bpf_dynptr_size(&ptr) != trim - off) {
255		err = 6;
256		goto done;
257	}
258
259done:
260	bpf_ringbuf_discard_dynptr(&ptr, 0);
261	return 0;
262}
263
264SEC("tp/syscalls/sys_enter_nanosleep")
265int test_adjust_err(void *ctx)
266{
267	char write_data[45] = "hello there, world!!";
268	struct bpf_dynptr ptr;
269	__u32 size = 64;
270	__u32 off = 20;
271
272	if (bpf_get_current_pid_tgid() >> 32 != pid)
273		return 0;
274
275	if (bpf_ringbuf_reserve_dynptr(&ringbuf, size, 0, &ptr)) {
276		err = 1;
277		goto done;
278	}
279
280	/* Check that start can't be greater than end */
281	if (bpf_dynptr_adjust(&ptr, 5, 1) != -EINVAL) {
282		err = 2;
283		goto done;
284	}
285
286	/* Check that start can't be greater than size */
287	if (bpf_dynptr_adjust(&ptr, size + 1, size + 1) != -ERANGE) {
288		err = 3;
289		goto done;
290	}
291
292	/* Check that end can't be greater than size */
293	if (bpf_dynptr_adjust(&ptr, 0, size + 1) != -ERANGE) {
294		err = 4;
295		goto done;
296	}
297
298	if (bpf_dynptr_adjust(&ptr, off, size)) {
299		err = 5;
300		goto done;
301	}
302
303	/* Check that you can't write more bytes than available into the dynptr
304	 * after you've adjusted it
305	 */
306	if (bpf_dynptr_write(&ptr, 0, &write_data, sizeof(write_data), 0) != -E2BIG) {
307		err = 6;
308		goto done;
309	}
310
311	/* Check that even after adjusting, submitting/discarding
312	 * a ringbuf dynptr works
313	 */
314	bpf_ringbuf_submit_dynptr(&ptr, 0);
315	return 0;
316
317done:
318	bpf_ringbuf_discard_dynptr(&ptr, 0);
319	return 0;
320}
321
322SEC("tp/syscalls/sys_enter_nanosleep")
323int test_zero_size_dynptr(void *ctx)
324{
325	char write_data = 'x', read_data;
326	struct bpf_dynptr ptr;
327	__u32 size = 64;
328
329	if (bpf_get_current_pid_tgid() >> 32 != pid)
330		return 0;
331
332	if (bpf_ringbuf_reserve_dynptr(&ringbuf, size, 0, &ptr)) {
333		err = 1;
334		goto done;
335	}
336
337	/* After this, the dynptr has a size of 0 */
338	if (bpf_dynptr_adjust(&ptr, size, size)) {
339		err = 2;
340		goto done;
341	}
342
343	/* Test that reading + writing non-zero bytes is not ok */
344	if (bpf_dynptr_read(&read_data, sizeof(read_data), &ptr, 0, 0) != -E2BIG) {
345		err = 3;
346		goto done;
347	}
348
349	if (bpf_dynptr_write(&ptr, 0, &write_data, sizeof(write_data), 0) != -E2BIG) {
350		err = 4;
351		goto done;
352	}
353
354	/* Test that reading + writing 0 bytes from a 0-size dynptr is ok */
355	if (bpf_dynptr_read(&read_data, 0, &ptr, 0, 0)) {
356		err = 5;
357		goto done;
358	}
359
360	if (bpf_dynptr_write(&ptr, 0, &write_data, 0, 0)) {
361		err = 6;
362		goto done;
363	}
364
365	err = 0;
366
367done:
368	bpf_ringbuf_discard_dynptr(&ptr, 0);
369	return 0;
370}
371
372SEC("tp/syscalls/sys_enter_nanosleep")
373int test_dynptr_is_null(void *ctx)
374{
375	struct bpf_dynptr ptr1;
376	struct bpf_dynptr ptr2;
377	__u64 size = 4;
378
379	if (bpf_get_current_pid_tgid() >> 32 != pid)
380		return 0;
381
382	/* Pass in invalid flags, get back an invalid dynptr */
383	if (bpf_ringbuf_reserve_dynptr(&ringbuf, size, 123, &ptr1) != -EINVAL) {
384		err = 1;
385		goto exit_early;
386	}
387
388	/* Test that the invalid dynptr is null */
389	if (!bpf_dynptr_is_null(&ptr1)) {
390		err = 2;
391		goto exit_early;
392	}
393
394	/* Get a valid dynptr */
395	if (bpf_ringbuf_reserve_dynptr(&ringbuf, size, 0, &ptr2)) {
396		err = 3;
397		goto exit;
398	}
399
400	/* Test that the valid dynptr is not null */
401	if (bpf_dynptr_is_null(&ptr2)) {
402		err = 4;
403		goto exit;
404	}
405
406exit:
407	bpf_ringbuf_discard_dynptr(&ptr2, 0);
408exit_early:
409	bpf_ringbuf_discard_dynptr(&ptr1, 0);
410	return 0;
411}
412
413SEC("cgroup_skb/egress")
414int test_dynptr_is_rdonly(struct __sk_buff *skb)
415{
416	struct bpf_dynptr ptr1;
417	struct bpf_dynptr ptr2;
418	struct bpf_dynptr ptr3;
419
420	/* Pass in invalid flags, get back an invalid dynptr */
421	if (bpf_dynptr_from_skb(skb, 123, &ptr1) != -EINVAL) {
422		err = 1;
423		return 0;
424	}
425
426	/* Test that an invalid dynptr is_rdonly returns false */
427	if (bpf_dynptr_is_rdonly(&ptr1)) {
428		err = 2;
429		return 0;
430	}
431
432	/* Get a read-only dynptr */
433	if (bpf_dynptr_from_skb(skb, 0, &ptr2)) {
434		err = 3;
435		return 0;
436	}
437
438	/* Test that the dynptr is read-only */
439	if (!bpf_dynptr_is_rdonly(&ptr2)) {
440		err = 4;
441		return 0;
442	}
443
444	/* Get a read-writeable dynptr */
445	if (bpf_ringbuf_reserve_dynptr(&ringbuf, 64, 0, &ptr3)) {
446		err = 5;
447		goto done;
448	}
449
450	/* Test that the dynptr is read-only */
451	if (bpf_dynptr_is_rdonly(&ptr3)) {
452		err = 6;
453		goto done;
454	}
455
456done:
457	bpf_ringbuf_discard_dynptr(&ptr3, 0);
458	return 0;
459}
460
461SEC("cgroup_skb/egress")
462int test_dynptr_clone(struct __sk_buff *skb)
463{
464	struct bpf_dynptr ptr1;
465	struct bpf_dynptr ptr2;
466	__u32 off = 2, size;
467
468	/* Get a dynptr */
469	if (bpf_dynptr_from_skb(skb, 0, &ptr1)) {
470		err = 1;
471		return 0;
472	}
473
474	if (bpf_dynptr_adjust(&ptr1, off, bpf_dynptr_size(&ptr1))) {
475		err = 2;
476		return 0;
477	}
478
479	/* Clone the dynptr */
480	if (bpf_dynptr_clone(&ptr1, &ptr2)) {
481		err = 3;
482		return 0;
483	}
484
485	size = bpf_dynptr_size(&ptr1);
486
487	/* Check that the clone has the same size and rd-only */
488	if (bpf_dynptr_size(&ptr2) != size) {
489		err = 4;
490		return 0;
491	}
492
493	if (bpf_dynptr_is_rdonly(&ptr2) != bpf_dynptr_is_rdonly(&ptr1)) {
494		err = 5;
495		return 0;
496	}
497
498	/* Advance and trim the original dynptr */
499	bpf_dynptr_adjust(&ptr1, 5, 5);
500
501	/* Check that only original dynptr was affected, and the clone wasn't */
502	if (bpf_dynptr_size(&ptr2) != size) {
503		err = 6;
504		return 0;
505	}
506
507	return 0;
508}
509
510SEC("?cgroup_skb/egress")
511int test_dynptr_skb_no_buff(struct __sk_buff *skb)
512{
513	struct bpf_dynptr ptr;
514	__u64 *data;
515
516	if (bpf_dynptr_from_skb(skb, 0, &ptr)) {
517		err = 1;
518		return 1;
519	}
520
521	/* This may return NULL. SKB may require a buffer */
522	data = bpf_dynptr_slice(&ptr, 0, NULL, 1);
523
524	return !!data;
525}
526
527SEC("?cgroup_skb/egress")
528int test_dynptr_skb_strcmp(struct __sk_buff *skb)
529{
530	struct bpf_dynptr ptr;
531	char *data;
532
533	if (bpf_dynptr_from_skb(skb, 0, &ptr)) {
534		err = 1;
535		return 1;
536	}
537
538	/* This may return NULL. SKB may require a buffer */
539	data = bpf_dynptr_slice(&ptr, 0, NULL, 10);
540	if (data) {
541		bpf_strncmp(data, 10, "foo");
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
542		return 1;
543	}
544
545	return 1;
546}