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 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 30 static int fn(void) 31 { 32 int err; 33 34 err = unshare(CLONE_NEWNS); 35 if (!ASSERT_OK(err, "unshare")) 36 goto out; 37 38 err = mount("", "/", "", MS_REC | MS_PRIVATE, NULL); 39 if (!ASSERT_OK(err, "mount /")) 40 goto out; 41 42 err = umount(TDIR); 43 if (!ASSERT_OK(err, "umount " TDIR)) 44 goto out; 45 46 err = mount("none", TDIR, "tmpfs", 0, NULL); 47 if (!ASSERT_OK(err, "mount tmpfs")) 48 goto out; 49 50 err = mkdir(TDIR "/fs1", 0777); 51 if (!ASSERT_OK(err, "mkdir " TDIR "/fs1")) 52 goto out; 53 err = mkdir(TDIR "/fs2", 0777); 54 if (!ASSERT_OK(err, "mkdir " TDIR "/fs2")) 55 goto out; 56 57 err = mount("bpf", TDIR "/fs1", "bpf", 0, NULL); 58 if (!ASSERT_OK(err, "mount bpffs " TDIR "/fs1")) 59 goto out; 60 err = mount("bpf", TDIR "/fs2", "bpf", 0, NULL); 61 if (!ASSERT_OK(err, "mount bpffs " TDIR "/fs2")) 62 goto out; 63 64 err = read_iter(TDIR "/fs1/maps.debug"); 65 if (!ASSERT_OK(err, "reading " TDIR "/fs1/maps.debug")) 66 goto out; 67 err = read_iter(TDIR "/fs2/progs.debug"); 68 if (!ASSERT_OK(err, "reading " TDIR "/fs2/progs.debug")) 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 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