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 
test_success(void)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.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 
test_rcuptr_acquire(void)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 = 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 	"rcu_read_lock_sleepable_helper_global_subprog",
85 	"rcu_read_lock_sleepable_kfunc_global_subprog",
86 	"rcu_read_lock_sleepable_global_subprog_indirect",
87 };
88 
test_inproper_region(void)89 static void test_inproper_region(void)
90 {
91 	struct rcu_read_lock *skel;
92 	struct bpf_program *prog;
93 	int i, err;
94 
95 	for (i = 0; i < ARRAY_SIZE(inproper_region_tests); i++) {
96 		skel = rcu_read_lock__open();
97 		if (!ASSERT_OK_PTR(skel, "skel_open"))
98 			return;
99 
100 		prog = bpf_object__find_program_by_name(skel->obj, inproper_region_tests[i]);
101 		if (!ASSERT_OK_PTR(prog, "bpf_object__find_program_by_name"))
102 			goto out;
103 		bpf_program__set_autoload(prog, true);
104 		err = rcu_read_lock__load(skel);
105 		ASSERT_ERR(err, "skel_load");
106 out:
107 		rcu_read_lock__destroy(skel);
108 	}
109 }
110 
111 static const char * const rcuptr_misuse_tests[] = {
112 	"task_untrusted_rcuptr",
113 	"cross_rcu_region",
114 };
115 
test_rcuptr_misuse(void)116 static void test_rcuptr_misuse(void)
117 {
118 	struct rcu_read_lock *skel;
119 	struct bpf_program *prog;
120 	int i, err;
121 
122 	for (i = 0; i < ARRAY_SIZE(rcuptr_misuse_tests); i++) {
123 		skel = rcu_read_lock__open();
124 		if (!ASSERT_OK_PTR(skel, "skel_open"))
125 			return;
126 
127 		prog = bpf_object__find_program_by_name(skel->obj, rcuptr_misuse_tests[i]);
128 		if (!ASSERT_OK_PTR(prog, "bpf_object__find_program_by_name"))
129 			goto out;
130 		bpf_program__set_autoload(prog, true);
131 		err = rcu_read_lock__load(skel);
132 		ASSERT_ERR(err, "skel_load");
133 out:
134 		rcu_read_lock__destroy(skel);
135 	}
136 }
137 
test_rcu_read_lock(void)138 void test_rcu_read_lock(void)
139 {
140 	int cgroup_fd;
141 
142 	cgroup_fd = test__join_cgroup("/rcu_read_lock");
143 	if (!ASSERT_GE(cgroup_fd, 0, "join_cgroup /rcu_read_lock"))
144 		goto out;
145 
146 	cgroup_id = get_cgroup_id("/rcu_read_lock");
147 	if (test__start_subtest("success"))
148 		test_success();
149 	if (test__start_subtest("rcuptr_acquire"))
150 		test_rcuptr_acquire();
151 	if (test__start_subtest("negative_tests_inproper_region"))
152 		test_inproper_region();
153 	if (test__start_subtest("negative_tests_rcuptr_misuse"))
154 		test_rcuptr_misuse();
155 	close(cgroup_fd);
156 out:;
157 }
158