1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2020 Facebook */
3 #define _GNU_SOURCE
4 #include <sched.h>
5 #include <sys/mount.h>
6 #include <sys/stat.h>
7 #include <sys/types.h>
8 #include <test_progs.h>
9
10 #define TDIR "/sys/kernel/debug"
11
read_iter(char * file)12 static int read_iter(char *file)
13 {
14 /* 1024 should be enough to get contiguous 4 "iter" letters at some point */
15 char buf[1024];
16 int fd, len;
17
18 fd = open(file, 0);
19 if (fd < 0)
20 return -1;
21 while ((len = read(fd, buf, sizeof(buf))) > 0)
22 if (strstr(buf, "iter")) {
23 close(fd);
24 return 0;
25 }
26 close(fd);
27 return -1;
28 }
29
fn(void)30 static int fn(void)
31 {
32 int err, duration = 0;
33
34 err = unshare(CLONE_NEWNS);
35 if (CHECK(err, "unshare", "failed: %d\n", errno))
36 goto out;
37
38 err = mount("", "/", "", MS_REC | MS_PRIVATE, NULL);
39 if (CHECK(err, "mount /", "failed: %d\n", errno))
40 goto out;
41
42 err = umount(TDIR);
43 if (CHECK(err, "umount " TDIR, "failed: %d\n", errno))
44 goto out;
45
46 err = mount("none", TDIR, "tmpfs", 0, NULL);
47 if (CHECK(err, "mount", "mount root failed: %d\n", errno))
48 goto out;
49
50 err = mkdir(TDIR "/fs1", 0777);
51 if (CHECK(err, "mkdir "TDIR"/fs1", "failed: %d\n", errno))
52 goto out;
53 err = mkdir(TDIR "/fs2", 0777);
54 if (CHECK(err, "mkdir "TDIR"/fs2", "failed: %d\n", errno))
55 goto out;
56
57 err = mount("bpf", TDIR "/fs1", "bpf", 0, NULL);
58 if (CHECK(err, "mount bpffs "TDIR"/fs1", "failed: %d\n", errno))
59 goto out;
60 err = mount("bpf", TDIR "/fs2", "bpf", 0, NULL);
61 if (CHECK(err, "mount bpffs " TDIR "/fs2", "failed: %d\n", errno))
62 goto out;
63
64 err = read_iter(TDIR "/fs1/maps.debug");
65 if (CHECK(err, "reading " TDIR "/fs1/maps.debug", "failed\n"))
66 goto out;
67 err = read_iter(TDIR "/fs2/progs.debug");
68 if (CHECK(err, "reading " TDIR "/fs2/progs.debug", "failed\n"))
69 goto out;
70 out:
71 umount(TDIR "/fs1");
72 umount(TDIR "/fs2");
73 rmdir(TDIR "/fs1");
74 rmdir(TDIR "/fs2");
75 umount(TDIR);
76 exit(err);
77 }
78
test_test_bpffs(void)79 void test_test_bpffs(void)
80 {
81 int err, duration = 0, status = 0;
82 pid_t pid;
83
84 pid = fork();
85 if (CHECK(pid == -1, "clone", "clone failed %d", errno))
86 return;
87 if (pid == 0)
88 fn();
89 err = waitpid(pid, &status, 0);
90 if (CHECK(err == -1 && errno != ECHILD, "waitpid", "failed %d", errno))
91 return;
92 if (CHECK(WEXITSTATUS(status), "bpffs test ", "failed %d", WEXITSTATUS(status)))
93 return;
94 }
95