xref: /linux/tools/testing/selftests/bpf/prog_tests/rcu_read_lock.c (revision e6a901a00822659181c93c86d8bbc2a17779fddc)
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 = syscall(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.task_trusted_non_rcuptr, true);
32 	bpf_program__set_autoload(skel->progs.rcu_read_lock_subprog, true);
33 	bpf_program__set_autoload(skel->progs.rcu_read_lock_global_subprog, true);
34 	bpf_program__set_autoload(skel->progs.rcu_read_lock_subprog_lock, true);
35 	bpf_program__set_autoload(skel->progs.rcu_read_lock_subprog_unlock, true);
36 	err = rcu_read_lock__load(skel);
37 	if (!ASSERT_OK(err, "skel_load"))
38 		goto out;
39 
40 	err = rcu_read_lock__attach(skel);
41 	if (!ASSERT_OK(err, "skel_attach"))
42 		goto out;
43 
44 	syscall(SYS_getpgid);
45 
46 	ASSERT_EQ(skel->bss->task_storage_val, 2, "task_storage_val");
47 	ASSERT_EQ(skel->bss->cgroup_id, cgroup_id, "cgroup_id");
48 out:
49 	rcu_read_lock__destroy(skel);
50 }
51 
52 static void test_rcuptr_acquire(void)
53 {
54 	struct rcu_read_lock *skel;
55 	int err;
56 
57 	skel = rcu_read_lock__open();
58 	if (!ASSERT_OK_PTR(skel, "skel_open"))
59 		return;
60 
61 	skel->bss->target_pid = syscall(SYS_gettid);
62 
63 	bpf_program__set_autoload(skel->progs.task_acquire, true);
64 	err = rcu_read_lock__load(skel);
65 	if (!ASSERT_OK(err, "skel_load"))
66 		goto out;
67 
68 	err = rcu_read_lock__attach(skel);
69 	ASSERT_OK(err, "skel_attach");
70 out:
71 	rcu_read_lock__destroy(skel);
72 }
73 
74 static const char * const inproper_region_tests[] = {
75 	"miss_lock",
76 	"no_lock",
77 	"miss_unlock",
78 	"non_sleepable_rcu_mismatch",
79 	"inproper_sleepable_helper",
80 	"inproper_sleepable_kfunc",
81 	"nested_rcu_region",
82 	"rcu_read_lock_global_subprog_lock",
83 	"rcu_read_lock_global_subprog_unlock",
84 };
85 
86 static void test_inproper_region(void)
87 {
88 	struct rcu_read_lock *skel;
89 	struct bpf_program *prog;
90 	int i, err;
91 
92 	for (i = 0; i < ARRAY_SIZE(inproper_region_tests); i++) {
93 		skel = rcu_read_lock__open();
94 		if (!ASSERT_OK_PTR(skel, "skel_open"))
95 			return;
96 
97 		prog = bpf_object__find_program_by_name(skel->obj, inproper_region_tests[i]);
98 		if (!ASSERT_OK_PTR(prog, "bpf_object__find_program_by_name"))
99 			goto out;
100 		bpf_program__set_autoload(prog, true);
101 		err = rcu_read_lock__load(skel);
102 		ASSERT_ERR(err, "skel_load");
103 out:
104 		rcu_read_lock__destroy(skel);
105 	}
106 }
107 
108 static const char * const rcuptr_misuse_tests[] = {
109 	"task_untrusted_rcuptr",
110 	"cross_rcu_region",
111 };
112 
113 static void test_rcuptr_misuse(void)
114 {
115 	struct rcu_read_lock *skel;
116 	struct bpf_program *prog;
117 	int i, err;
118 
119 	for (i = 0; i < ARRAY_SIZE(rcuptr_misuse_tests); i++) {
120 		skel = rcu_read_lock__open();
121 		if (!ASSERT_OK_PTR(skel, "skel_open"))
122 			return;
123 
124 		prog = bpf_object__find_program_by_name(skel->obj, rcuptr_misuse_tests[i]);
125 		if (!ASSERT_OK_PTR(prog, "bpf_object__find_program_by_name"))
126 			goto out;
127 		bpf_program__set_autoload(prog, true);
128 		err = rcu_read_lock__load(skel);
129 		ASSERT_ERR(err, "skel_load");
130 out:
131 		rcu_read_lock__destroy(skel);
132 	}
133 }
134 
135 void test_rcu_read_lock(void)
136 {
137 	int cgroup_fd;
138 
139 	cgroup_fd = test__join_cgroup("/rcu_read_lock");
140 	if (!ASSERT_GE(cgroup_fd, 0, "join_cgroup /rcu_read_lock"))
141 		goto out;
142 
143 	cgroup_id = get_cgroup_id("/rcu_read_lock");
144 	if (test__start_subtest("success"))
145 		test_success();
146 	if (test__start_subtest("rcuptr_acquire"))
147 		test_rcuptr_acquire();
148 	if (test__start_subtest("negative_tests_inproper_region"))
149 		test_inproper_region();
150 	if (test__start_subtest("negative_tests_rcuptr_misuse"))
151 		test_rcuptr_misuse();
152 	close(cgroup_fd);
153 out:;
154 }
155