1// SPDX-License-Identifier: GPL-2.0
2/* Copyright (c) 2020 Facebook */
3
4#include <test_progs.h>
5
6#include "test_btf_map_in_map.skel.h"
7
8static int duration;
9
10static __u32 bpf_map_id(struct bpf_map *map)
11{
12	struct bpf_map_info info;
13	__u32 info_len = sizeof(info);
14	int err;
15
16	memset(&info, 0, info_len);
17	err = bpf_map_get_info_by_fd(bpf_map__fd(map), &info, &info_len);
18	if (err)
19		return 0;
20	return info.id;
21}
22
23static void test_lookup_update(void)
24{
25	int map1_fd, map2_fd, map3_fd, map4_fd, map5_fd, map1_id, map2_id;
26	int outer_arr_fd, outer_hash_fd, outer_arr_dyn_fd;
27	struct test_btf_map_in_map *skel;
28	int err, key = 0, val, i, fd;
29
30	skel = test_btf_map_in_map__open_and_load();
31	if (CHECK(!skel, "skel_open", "failed to open&load skeleton\n"))
32		return;
33
34	err = test_btf_map_in_map__attach(skel);
35	if (CHECK(err, "skel_attach", "skeleton attach failed: %d\n", err))
36		goto cleanup;
37
38	map1_fd = bpf_map__fd(skel->maps.inner_map1);
39	map2_fd = bpf_map__fd(skel->maps.inner_map2);
40	map3_fd = bpf_map__fd(skel->maps.inner_map3);
41	map4_fd = bpf_map__fd(skel->maps.inner_map4);
42	map5_fd = bpf_map__fd(skel->maps.inner_map5);
43	outer_arr_dyn_fd = bpf_map__fd(skel->maps.outer_arr_dyn);
44	outer_arr_fd = bpf_map__fd(skel->maps.outer_arr);
45	outer_hash_fd = bpf_map__fd(skel->maps.outer_hash);
46
47	/* inner1 = input, inner2 = input + 1, inner3 = input + 2 */
48	bpf_map_update_elem(outer_arr_fd, &key, &map1_fd, 0);
49	bpf_map_update_elem(outer_hash_fd, &key, &map2_fd, 0);
50	bpf_map_update_elem(outer_arr_dyn_fd, &key, &map3_fd, 0);
51	skel->bss->input = 1;
52	usleep(1);
53	bpf_map_lookup_elem(map1_fd, &key, &val);
54	CHECK(val != 1, "inner1", "got %d != exp %d\n", val, 1);
55	bpf_map_lookup_elem(map2_fd, &key, &val);
56	CHECK(val != 2, "inner2", "got %d != exp %d\n", val, 2);
57	bpf_map_lookup_elem(map3_fd, &key, &val);
58	CHECK(val != 3, "inner3", "got %d != exp %d\n", val, 3);
59
60	/* inner2 = input, inner1 = input + 1, inner4 = input + 2 */
61	bpf_map_update_elem(outer_arr_fd, &key, &map2_fd, 0);
62	bpf_map_update_elem(outer_hash_fd, &key, &map1_fd, 0);
63	bpf_map_update_elem(outer_arr_dyn_fd, &key, &map4_fd, 0);
64	skel->bss->input = 3;
65	usleep(1);
66	bpf_map_lookup_elem(map1_fd, &key, &val);
67	CHECK(val != 4, "inner1", "got %d != exp %d\n", val, 4);
68	bpf_map_lookup_elem(map2_fd, &key, &val);
69	CHECK(val != 3, "inner2", "got %d != exp %d\n", val, 3);
70	bpf_map_lookup_elem(map4_fd, &key, &val);
71	CHECK(val != 5, "inner4", "got %d != exp %d\n", val, 5);
72
73	/* inner5 = input + 2 */
74	bpf_map_update_elem(outer_arr_dyn_fd, &key, &map5_fd, 0);
75	skel->bss->input = 5;
76	usleep(1);
77	bpf_map_lookup_elem(map5_fd, &key, &val);
78	CHECK(val != 7, "inner5", "got %d != exp %d\n", val, 7);
79
80	for (i = 0; i < 5; i++) {
81		val = i % 2 ? map1_fd : map2_fd;
82		err = bpf_map_update_elem(outer_hash_fd, &key, &val, 0);
83		if (CHECK_FAIL(err)) {
84			printf("failed to update hash_of_maps on iter #%d\n", i);
85			goto cleanup;
86		}
87		err = bpf_map_update_elem(outer_arr_fd, &key, &val, 0);
88		if (CHECK_FAIL(err)) {
89			printf("failed to update array_of_maps on iter #%d\n", i);
90			goto cleanup;
91		}
92		val = i % 2 ? map4_fd : map5_fd;
93		err = bpf_map_update_elem(outer_arr_dyn_fd, &key, &val, 0);
94		if (CHECK_FAIL(err)) {
95			printf("failed to update array_of_maps (dyn) on iter #%d\n", i);
96			goto cleanup;
97		}
98	}
99
100	map1_id = bpf_map_id(skel->maps.inner_map1);
101	map2_id = bpf_map_id(skel->maps.inner_map2);
102	CHECK(map1_id == 0, "map1_id", "failed to get ID 1\n");
103	CHECK(map2_id == 0, "map2_id", "failed to get ID 2\n");
104
105	test_btf_map_in_map__destroy(skel);
106	skel = NULL;
107
108	/* we need to either wait for or force synchronize_rcu(), before
109	 * checking for "still exists" condition, otherwise map could still be
110	 * resolvable by ID, causing false positives.
111	 *
112	 * Older kernels (5.8 and earlier) freed map only after two
113	 * synchronize_rcu()s, so trigger two, to be entirely sure.
114	 */
115	CHECK(kern_sync_rcu(), "sync_rcu", "failed\n");
116	CHECK(kern_sync_rcu(), "sync_rcu", "failed\n");
117
118	fd = bpf_map_get_fd_by_id(map1_id);
119	if (CHECK(fd >= 0, "map1_leak", "inner_map1 leaked!\n")) {
120		close(fd);
121		goto cleanup;
122	}
123	fd = bpf_map_get_fd_by_id(map2_id);
124	if (CHECK(fd >= 0, "map2_leak", "inner_map2 leaked!\n")) {
125		close(fd);
126		goto cleanup;
127	}
128
129cleanup:
130	test_btf_map_in_map__destroy(skel);
131}
132
133static void test_diff_size(void)
134{
135	struct test_btf_map_in_map *skel;
136	int err, inner_map_fd, zero = 0;
137
138	skel = test_btf_map_in_map__open_and_load();
139	if (CHECK(!skel, "skel_open", "failed to open&load skeleton\n"))
140		return;
141
142	inner_map_fd = bpf_map__fd(skel->maps.sockarr_sz2);
143	err = bpf_map_update_elem(bpf_map__fd(skel->maps.outer_sockarr), &zero,
144				  &inner_map_fd, 0);
145	CHECK(err, "outer_sockarr inner map size check",
146	      "cannot use a different size inner_map\n");
147
148	inner_map_fd = bpf_map__fd(skel->maps.inner_map_sz2);
149	err = bpf_map_update_elem(bpf_map__fd(skel->maps.outer_arr), &zero,
150				  &inner_map_fd, 0);
151	CHECK(!err, "outer_arr inner map size check",
152	      "incorrectly updated with a different size inner_map\n");
153
154	test_btf_map_in_map__destroy(skel);
155}
156
157void test_btf_map_in_map(void)
158{
159	if (test__start_subtest("lookup_update"))
160		test_lookup_update();
161
162	if (test__start_subtest("diff_size"))
163		test_diff_size();
164}
165