xref: /linux/tools/testing/selftests/bpf/prog_tests/rcu_read_lock.c (revision 6dfafbd0299a60bfb5d5e277fdf100037c7ded07)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2022 Meta Platforms, Inc. and affiliates.*/
3 
4 #define _GNU_SOURCE
5 #include <unistd.h>
6 #include <sys/syscall.h>
7 #include <sys/types.h>
8 #include <test_progs.h>
9 #include <bpf/btf.h>
10 #include "rcu_read_lock.skel.h"
11 #include "cgroup_helpers.h"
12 
13 static unsigned long long cgroup_id;
14 
15 static void test_success(void)
16 {
17 	struct rcu_read_lock *skel;
18 	int err;
19 
20 	skel = rcu_read_lock__open();
21 	if (!ASSERT_OK_PTR(skel, "skel_open"))
22 		return;
23 
24 	skel->bss->target_pid = sys_gettid();
25 
26 	bpf_program__set_autoload(skel->progs.get_cgroup_id, true);
27 	bpf_program__set_autoload(skel->progs.task_succ, true);
28 	bpf_program__set_autoload(skel->progs.two_regions, true);
29 	bpf_program__set_autoload(skel->progs.non_sleepable_1, true);
30 	bpf_program__set_autoload(skel->progs.non_sleepable_2, true);
31 	bpf_program__set_autoload(skel->progs.nested_rcu_region, true);
32 	bpf_program__set_autoload(skel->progs.task_trusted_non_rcuptr, true);
33 	bpf_program__set_autoload(skel->progs.rcu_read_lock_subprog, true);
34 	bpf_program__set_autoload(skel->progs.rcu_read_lock_global_subprog, true);
35 	bpf_program__set_autoload(skel->progs.rcu_read_lock_subprog_lock, true);
36 	bpf_program__set_autoload(skel->progs.rcu_read_lock_subprog_unlock, true);
37 	err = rcu_read_lock__load(skel);
38 	if (!ASSERT_OK(err, "skel_load"))
39 		goto out;
40 
41 	err = rcu_read_lock__attach(skel);
42 	if (!ASSERT_OK(err, "skel_attach"))
43 		goto out;
44 
45 	syscall(SYS_getpgid);
46 
47 	ASSERT_EQ(skel->bss->task_storage_val, 2, "task_storage_val");
48 	ASSERT_EQ(skel->bss->cgroup_id, cgroup_id, "cgroup_id");
49 out:
50 	rcu_read_lock__destroy(skel);
51 }
52 
53 static void test_rcuptr_acquire(void)
54 {
55 	struct rcu_read_lock *skel;
56 	int err;
57 
58 	skel = rcu_read_lock__open();
59 	if (!ASSERT_OK_PTR(skel, "skel_open"))
60 		return;
61 
62 	skel->bss->target_pid = sys_gettid();
63 
64 	bpf_program__set_autoload(skel->progs.task_acquire, true);
65 	err = rcu_read_lock__load(skel);
66 	if (!ASSERT_OK(err, "skel_load"))
67 		goto out;
68 
69 	err = rcu_read_lock__attach(skel);
70 	ASSERT_OK(err, "skel_attach");
71 out:
72 	rcu_read_lock__destroy(skel);
73 }
74 
75 static const char * const inproper_region_tests[] = {
76 	"miss_lock",
77 	"no_lock",
78 	"miss_unlock",
79 	"non_sleepable_rcu_mismatch",
80 	"inproper_sleepable_helper",
81 	"inproper_sleepable_kfunc",
82 	"nested_rcu_region_unbalanced_1",
83 	"nested_rcu_region_unbalanced_2",
84 	"rcu_read_lock_global_subprog_lock",
85 	"rcu_read_lock_global_subprog_unlock",
86 	"rcu_read_lock_sleepable_helper_global_subprog",
87 	"rcu_read_lock_sleepable_kfunc_global_subprog",
88 	"rcu_read_lock_sleepable_global_subprog_indirect",
89 };
90 
91 static void test_inproper_region(void)
92 {
93 	struct rcu_read_lock *skel;
94 	struct bpf_program *prog;
95 	int i, err;
96 
97 	for (i = 0; i < ARRAY_SIZE(inproper_region_tests); i++) {
98 		skel = rcu_read_lock__open();
99 		if (!ASSERT_OK_PTR(skel, "skel_open"))
100 			return;
101 
102 		prog = bpf_object__find_program_by_name(skel->obj, inproper_region_tests[i]);
103 		if (!ASSERT_OK_PTR(prog, "bpf_object__find_program_by_name"))
104 			goto out;
105 		bpf_program__set_autoload(prog, true);
106 		err = rcu_read_lock__load(skel);
107 		ASSERT_ERR(err, "skel_load");
108 out:
109 		rcu_read_lock__destroy(skel);
110 	}
111 }
112 
113 static const char * const rcuptr_misuse_tests[] = {
114 	"task_untrusted_rcuptr",
115 	"cross_rcu_region",
116 };
117 
118 static void test_rcuptr_misuse(void)
119 {
120 	struct rcu_read_lock *skel;
121 	struct bpf_program *prog;
122 	int i, err;
123 
124 	for (i = 0; i < ARRAY_SIZE(rcuptr_misuse_tests); i++) {
125 		skel = rcu_read_lock__open();
126 		if (!ASSERT_OK_PTR(skel, "skel_open"))
127 			return;
128 
129 		prog = bpf_object__find_program_by_name(skel->obj, rcuptr_misuse_tests[i]);
130 		if (!ASSERT_OK_PTR(prog, "bpf_object__find_program_by_name"))
131 			goto out;
132 		bpf_program__set_autoload(prog, true);
133 		err = rcu_read_lock__load(skel);
134 		ASSERT_ERR(err, "skel_load");
135 out:
136 		rcu_read_lock__destroy(skel);
137 	}
138 }
139 
140 void test_rcu_read_lock(void)
141 {
142 	int cgroup_fd;
143 
144 	cgroup_fd = test__join_cgroup("/rcu_read_lock");
145 	if (!ASSERT_GE(cgroup_fd, 0, "join_cgroup /rcu_read_lock"))
146 		goto out;
147 
148 	cgroup_id = get_cgroup_id("/rcu_read_lock");
149 	if (test__start_subtest("success"))
150 		test_success();
151 	if (test__start_subtest("rcuptr_acquire"))
152 		test_rcuptr_acquire();
153 	if (test__start_subtest("negative_tests_inproper_region"))
154 		test_inproper_region();
155 	if (test__start_subtest("negative_tests_rcuptr_misuse"))
156 		test_rcuptr_misuse();
157 	close(cgroup_fd);
158 out:;
159 }
160