1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2020 Facebook */
3 #define _GNU_SOURCE
4 #include <stdio.h>
5 #include <sched.h>
6 #include <sys/mount.h>
7 #include <sys/stat.h>
8 #include <sys/types.h>
9 #include <test_progs.h>
10
11 #define TDIR "/sys/kernel/debug"
12
read_iter(char * file)13 static int read_iter(char *file)
14 {
15 /* 1024 should be enough to get contiguous 4 "iter" letters at some point */
16 char buf[1024];
17 int fd, len;
18
19 fd = open(file, 0);
20 if (fd < 0)
21 return -1;
22 while ((len = read(fd, buf, sizeof(buf))) > 0) {
23 buf[sizeof(buf) - 1] = '\0';
24 if (strstr(buf, "iter")) {
25 close(fd);
26 return 0;
27 }
28 }
29 close(fd);
30 return -1;
31 }
32
fn(void)33 static int fn(void)
34 {
35 struct stat a, b, c;
36 int err, map;
37
38 err = unshare(CLONE_NEWNS);
39 if (!ASSERT_OK(err, "unshare"))
40 goto out;
41
42 err = mount("", "/", "", MS_REC | MS_PRIVATE, NULL);
43 if (!ASSERT_OK(err, "mount /"))
44 goto out;
45
46 err = umount(TDIR);
47 if (!ASSERT_OK(err, "umount " TDIR))
48 goto out;
49
50 err = mount("none", TDIR, "tmpfs", 0, NULL);
51 if (!ASSERT_OK(err, "mount tmpfs"))
52 goto out;
53
54 err = mkdir(TDIR "/fs1", 0777);
55 if (!ASSERT_OK(err, "mkdir " TDIR "/fs1"))
56 goto out;
57 err = mkdir(TDIR "/fs2", 0777);
58 if (!ASSERT_OK(err, "mkdir " TDIR "/fs2"))
59 goto out;
60
61 err = mount("bpf", TDIR "/fs1", "bpf", 0, NULL);
62 if (!ASSERT_OK(err, "mount bpffs " TDIR "/fs1"))
63 goto out;
64 err = mount("bpf", TDIR "/fs2", "bpf", 0, NULL);
65 if (!ASSERT_OK(err, "mount bpffs " TDIR "/fs2"))
66 goto out;
67
68 err = read_iter(TDIR "/fs1/maps.debug");
69 if (!ASSERT_OK(err, "reading " TDIR "/fs1/maps.debug"))
70 goto out;
71 err = read_iter(TDIR "/fs2/progs.debug");
72 if (!ASSERT_OK(err, "reading " TDIR "/fs2/progs.debug"))
73 goto out;
74
75 err = mkdir(TDIR "/fs1/a", 0777);
76 if (!ASSERT_OK(err, "creating " TDIR "/fs1/a"))
77 goto out;
78 err = mkdir(TDIR "/fs1/a/1", 0777);
79 if (!ASSERT_OK(err, "creating " TDIR "/fs1/a/1"))
80 goto out;
81 err = mkdir(TDIR "/fs1/b", 0777);
82 if (!ASSERT_OK(err, "creating " TDIR "/fs1/b"))
83 goto out;
84
85 map = bpf_map_create(BPF_MAP_TYPE_ARRAY, NULL, 4, 4, 1, NULL);
86 if (!ASSERT_GT(map, 0, "create_map(ARRAY)"))
87 goto out;
88 err = bpf_obj_pin(map, TDIR "/fs1/c");
89 if (!ASSERT_OK(err, "pin map"))
90 goto out;
91 close(map);
92
93 /* Check that RENAME_EXCHANGE works for directories. */
94 err = stat(TDIR "/fs1/a", &a);
95 if (!ASSERT_OK(err, "stat(" TDIR "/fs1/a)"))
96 goto out;
97 err = renameat2(0, TDIR "/fs1/a", 0, TDIR "/fs1/b", RENAME_EXCHANGE);
98 if (!ASSERT_OK(err, "renameat2(/fs1/a, /fs1/b, RENAME_EXCHANGE)"))
99 goto out;
100 err = stat(TDIR "/fs1/b", &b);
101 if (!ASSERT_OK(err, "stat(" TDIR "/fs1/b)"))
102 goto out;
103 if (!ASSERT_EQ(a.st_ino, b.st_ino, "b should have a's inode"))
104 goto out;
105 err = access(TDIR "/fs1/b/1", F_OK);
106 if (!ASSERT_OK(err, "access(" TDIR "/fs1/b/1)"))
107 goto out;
108
109 /* Check that RENAME_EXCHANGE works for mixed file types. */
110 err = stat(TDIR "/fs1/c", &c);
111 if (!ASSERT_OK(err, "stat(" TDIR "/fs1/map)"))
112 goto out;
113 err = renameat2(0, TDIR "/fs1/c", 0, TDIR "/fs1/b", RENAME_EXCHANGE);
114 if (!ASSERT_OK(err, "renameat2(/fs1/c, /fs1/b, RENAME_EXCHANGE)"))
115 goto out;
116 err = stat(TDIR "/fs1/b", &b);
117 if (!ASSERT_OK(err, "stat(" TDIR "/fs1/b)"))
118 goto out;
119 if (!ASSERT_EQ(c.st_ino, b.st_ino, "b should have c's inode"))
120 goto out;
121 err = access(TDIR "/fs1/c/1", F_OK);
122 if (!ASSERT_OK(err, "access(" TDIR "/fs1/c/1)"))
123 goto out;
124
125 /* Check that RENAME_NOREPLACE works. */
126 err = renameat2(0, TDIR "/fs1/b", 0, TDIR "/fs1/a", RENAME_NOREPLACE);
127 if (!ASSERT_ERR(err, "renameat2(RENAME_NOREPLACE)")) {
128 err = -EINVAL;
129 goto out;
130 }
131 err = access(TDIR "/fs1/b", F_OK);
132 if (!ASSERT_OK(err, "access(" TDIR "/fs1/b)"))
133 goto out;
134
135 out:
136 umount(TDIR "/fs1");
137 umount(TDIR "/fs2");
138 rmdir(TDIR "/fs1");
139 rmdir(TDIR "/fs2");
140 umount(TDIR);
141 exit(err);
142 }
143
test_test_bpffs(void)144 void test_test_bpffs(void)
145 {
146 int err, duration = 0, status = 0;
147 pid_t pid;
148
149 pid = fork();
150 if (CHECK(pid == -1, "clone", "clone failed %d", errno))
151 return;
152 if (pid == 0)
153 fn();
154 err = waitpid(pid, &status, 0);
155 if (CHECK(err == -1 && errno != ECHILD, "waitpid", "failed %d", errno))
156 return;
157 if (CHECK(WEXITSTATUS(status), "bpffs test ", "failed %d", WEXITSTATUS(status)))
158 return;
159 }
160