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
12static 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
30static 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;
70out:
71	umount(TDIR "/fs1");
72	umount(TDIR "/fs2");
73	rmdir(TDIR "/fs1");
74	rmdir(TDIR "/fs2");
75	umount(TDIR);
76	exit(err);
77}
78
79void 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}