/* SPDX-License-Identifier: LGPL-2.1-or-later */ #include <sys/mount.h> #include <sys/statvfs.h> #include "alloc-util.h" #include "capability-util.h" #include "fd-util.h" #include "fileio.h" #include "fs-util.h" #include "libmount-util.h" #include "missing_magic.h" #include "missing_mount.h" #include "mkdir.h" #include "mount-util.h" #include "mountpoint-util.h" #include "namespace-util.h" #include "path-util.h" #include "process-util.h" #include "random-util.h" #include "rm-rf.h" #include "stat-util.h" #include "string-util.h" #include "strv.h" #include "tests.h" #include "tmpfile-util.h" TEST(mount_option_mangle) { char *opts = NULL; unsigned long f; assert_se(mount_option_mangle(NULL, MS_RDONLY|MS_NOSUID, &f, &opts) == 0); assert_se(f == (MS_RDONLY|MS_NOSUID)); assert_se(opts == NULL); assert_se(mount_option_mangle("", MS_RDONLY|MS_NOSUID, &f, &opts) == 0); assert_se(f == (MS_RDONLY|MS_NOSUID)); assert_se(opts == NULL); assert_se(mount_option_mangle("ro,nosuid,nodev,noexec", 0, &f, &opts) == 0); assert_se(f == (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC)); assert_se(opts == NULL); assert_se(mount_option_mangle("ro,nosuid,nodev,noexec,mode=0755", 0, &f, &opts) == 0); assert_se(f == (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC)); assert_se(streq(opts, "mode=0755")); opts = mfree(opts); assert_se(mount_option_mangle("rw,nosuid,foo,hogehoge,nodev,mode=0755", 0, &f, &opts) == 0); assert_se(f == (MS_NOSUID|MS_NODEV)); assert_se(streq(opts, "foo,hogehoge,mode=0755")); opts = mfree(opts); assert_se(mount_option_mangle("rw,nosuid,nodev,noexec,relatime,net_cls,net_prio", MS_RDONLY, &f, &opts) == 0); assert_se(f == (MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_RELATIME)); assert_se(streq(opts, "net_cls,net_prio")); opts = mfree(opts); assert_se(mount_option_mangle("rw,nosuid,nodev,relatime,size=1630748k,mode=0700,uid=1000,gid=1000", MS_RDONLY, &f, &opts) == 0); assert_se(f == (MS_NOSUID|MS_NODEV|MS_RELATIME)); assert_se(streq(opts, "size=1630748k,mode=0700,uid=1000,gid=1000")); opts = mfree(opts); assert_se(mount_option_mangle("size=1630748k,rw,gid=1000,,,nodev,relatime,,mode=0700,nosuid,uid=1000", MS_RDONLY, &f, &opts) == 0); assert_se(f == (MS_NOSUID|MS_NODEV|MS_RELATIME)); assert_se(streq(opts, "size=1630748k,gid=1000,mode=0700,uid=1000")); opts = mfree(opts); assert_se(mount_option_mangle("rw,exec,size=8143984k,nr_inodes=2035996,mode=0755", MS_RDONLY|MS_NOSUID|MS_NOEXEC|MS_NODEV, &f, &opts) == 0); assert_se(f == (MS_NOSUID|MS_NODEV)); assert_se(streq(opts, "size=8143984k,nr_inodes=2035996,mode=0755")); opts = mfree(opts); assert_se(mount_option_mangle("rw,relatime,fmask=0022,,,dmask=0022", MS_RDONLY, &f, &opts) == 0); assert_se(f == MS_RELATIME); assert_se(streq(opts, "fmask=0022,dmask=0022")); opts = mfree(opts); assert_se(mount_option_mangle("rw,relatime,fmask=0022,dmask=0022,\"hogehoge", MS_RDONLY, &f, &opts) < 0); assert_se(mount_option_mangle("mode=01777,size=10%,nr_inodes=400k,uid=496107520,gid=496107520,context=\"system_u:object_r:svirt_sandbox_file_t:s0:c0,c1\"", 0, &f, &opts) == 0); assert_se(f == 0); assert_se(streq(opts, "mode=01777,size=10%,nr_inodes=400k,uid=496107520,gid=496107520,context=\"system_u:object_r:svirt_sandbox_file_t:s0:c0,c1\"")); opts = mfree(opts); } static void test_mount_flags_to_string_one(unsigned long flags, const char *expected) { _cleanup_free_ char *x = NULL; int r; r = mount_flags_to_string(flags, &x); log_info("flags: %#lX → %d/\"%s\"", flags, r, strnull(x)); assert_se(r >= 0); assert_se(streq(x, expected)); } TEST(mount_flags_to_string) { test_mount_flags_to_string_one(0, "0"); test_mount_flags_to_string_one(MS_RDONLY, "MS_RDONLY"); test_mount_flags_to_string_one(MS_NOSUID, "MS_NOSUID"); test_mount_flags_to_string_one(MS_NODEV, "MS_NODEV"); test_mount_flags_to_string_one(MS_NOEXEC, "MS_NOEXEC"); test_mount_flags_to_string_one(MS_SYNCHRONOUS, "MS_SYNCHRONOUS"); test_mount_flags_to_string_one(MS_REMOUNT, "MS_REMOUNT"); test_mount_flags_to_string_one(MS_MANDLOCK, "MS_MANDLOCK"); test_mount_flags_to_string_one(MS_DIRSYNC, "MS_DIRSYNC"); test_mount_flags_to_string_one(MS_NOSYMFOLLOW, "MS_NOSYMFOLLOW"); test_mount_flags_to_string_one(MS_NOATIME, "MS_NOATIME"); test_mount_flags_to_string_one(MS_NODIRATIME, "MS_NODIRATIME"); test_mount_flags_to_string_one(MS_BIND, "MS_BIND"); test_mount_flags_to_string_one(MS_MOVE, "MS_MOVE"); test_mount_flags_to_string_one(MS_REC, "MS_REC"); test_mount_flags_to_string_one(MS_SILENT, "MS_SILENT"); test_mount_flags_to_string_one(MS_POSIXACL, "MS_POSIXACL"); test_mount_flags_to_string_one(MS_UNBINDABLE, "MS_UNBINDABLE"); test_mount_flags_to_string_one(MS_PRIVATE, "MS_PRIVATE"); test_mount_flags_to_string_one(MS_SLAVE, "MS_SLAVE"); test_mount_flags_to_string_one(MS_SHARED, "MS_SHARED"); test_mount_flags_to_string_one(MS_RELATIME, "MS_RELATIME"); test_mount_flags_to_string_one(MS_KERNMOUNT, "MS_KERNMOUNT"); test_mount_flags_to_string_one(MS_I_VERSION, "MS_I_VERSION"); test_mount_flags_to_string_one(MS_STRICTATIME, "MS_STRICTATIME"); test_mount_flags_to_string_one(MS_LAZYTIME, "MS_LAZYTIME"); test_mount_flags_to_string_one(MS_LAZYTIME|MS_STRICTATIME, "MS_STRICTATIME|MS_LAZYTIME"); test_mount_flags_to_string_one(UINT_MAX, "MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_SYNCHRONOUS|MS_REMOUNT|" "MS_MANDLOCK|MS_DIRSYNC|MS_NOSYMFOLLOW|MS_NOATIME|MS_NODIRATIME|" "MS_BIND|MS_MOVE|MS_REC|MS_SILENT|MS_POSIXACL|MS_UNBINDABLE|" "MS_PRIVATE|MS_SLAVE|MS_SHARED|MS_RELATIME|MS_KERNMOUNT|" "MS_I_VERSION|MS_STRICTATIME|MS_LAZYTIME|fc000200"); } TEST(bind_remount_recursive) { _cleanup_(rm_rf_physical_and_freep) char *tmp = NULL; _cleanup_free_ char *subdir = NULL; if (geteuid() != 0 || have_effective_cap(CAP_SYS_ADMIN) <= 0) { (void) log_tests_skipped("not running privileged"); return; } assert_se(mkdtemp_malloc("/tmp/XXXXXX", &tmp) >= 0); subdir = path_join(tmp, "subdir"); assert_se(subdir); assert_se(mkdir(subdir, 0755) >= 0); FOREACH_STRING(p, "/usr", "/sys", "/", tmp) { pid_t pid; pid = fork(); assert_se(pid >= 0); if (pid == 0) { struct statvfs svfs; /* child */ assert_se(detach_mount_namespace() >= 0); /* Check that the subdir is writable (it must be because it's in /tmp) */ assert_se(statvfs(subdir, &svfs) >= 0); assert_se(!FLAGS_SET(svfs.f_flag, ST_RDONLY)); /* Make the subdir a bind mount */ assert_se(mount_nofollow(subdir, subdir, NULL, MS_BIND|MS_REC, NULL) >= 0); /* Ensure it's still writable */ assert_se(statvfs(subdir, &svfs) >= 0); assert_se(!FLAGS_SET(svfs.f_flag, ST_RDONLY)); /* Now mark the path we currently run for read-only */ assert_se(bind_remount_recursive(p, MS_RDONLY, MS_RDONLY, path_equal(p, "/sys") ? STRV_MAKE("/sys/kernel") : NULL) >= 0); /* Ensure that this worked on the top-level */ assert_se(statvfs(p, &svfs) >= 0); assert_se(FLAGS_SET(svfs.f_flag, ST_RDONLY)); /* And ensure this had an effect on the subdir exactly if we are talking about a path above the subdir */ assert_se(statvfs(subdir, &svfs) >= 0); assert_se(FLAGS_SET(svfs.f_flag, ST_RDONLY) == !!path_startswith(subdir, p)); _exit(EXIT_SUCCESS); } assert_se(wait_for_terminate_and_check("test-remount-rec", pid, WAIT_LOG) == EXIT_SUCCESS); } } TEST(bind_remount_one) { pid_t pid; if (geteuid() != 0 || have_effective_cap(CAP_SYS_ADMIN) <= 0) { (void) log_tests_skipped("not running privileged"); return; } pid = fork(); assert_se(pid >= 0); if (pid == 0) { /* child */ _cleanup_fclose_ FILE *proc_self_mountinfo = NULL; assert_se(detach_mount_namespace() >= 0); assert_se(fopen_unlocked("/proc/self/mountinfo", "re", &proc_self_mountinfo) >= 0); assert_se(bind_remount_one_with_mountinfo("/run", MS_RDONLY, MS_RDONLY, proc_self_mountinfo) >= 0); assert_se(bind_remount_one_with_mountinfo("/run", MS_NOEXEC, MS_RDONLY|MS_NOEXEC, proc_self_mountinfo) >= 0); assert_se(bind_remount_one_with_mountinfo("/proc/idontexist", MS_RDONLY, MS_RDONLY, proc_self_mountinfo) == -ENOENT); assert_se(bind_remount_one_with_mountinfo("/proc/self", MS_RDONLY, MS_RDONLY, proc_self_mountinfo) == -EINVAL); assert_se(bind_remount_one_with_mountinfo("/", MS_RDONLY, MS_RDONLY, proc_self_mountinfo) >= 0); _exit(EXIT_SUCCESS); } assert_se(wait_for_terminate_and_check("test-remount-one", pid, WAIT_LOG) == EXIT_SUCCESS); } TEST(make_mount_point_inode) { _cleanup_(rm_rf_physical_and_freep) char *d = NULL; const char *src_file, *src_dir, *dst_file, *dst_dir; struct stat st; assert_se(mkdtemp_malloc(NULL, &d) >= 0); src_file = strjoina(d, "/src/file"); src_dir = strjoina(d, "/src/dir"); dst_file = strjoina(d, "/dst/file"); dst_dir = strjoina(d, "/dst/dir"); assert_se(mkdir_p(src_dir, 0755) >= 0); assert_se(mkdir_parents(dst_file, 0755) >= 0); assert_se(touch(src_file) >= 0); assert_se(make_mount_point_inode_from_path(src_file, dst_file, 0755) >= 0); assert_se(make_mount_point_inode_from_path(src_dir, dst_dir, 0755) >= 0); assert_se(stat(dst_dir, &st) == 0); assert_se(S_ISDIR(st.st_mode)); assert_se(stat(dst_file, &st) == 0); assert_se(S_ISREG(st.st_mode)); assert_se(!(S_IXUSR & st.st_mode)); assert_se(!(S_IXGRP & st.st_mode)); assert_se(!(S_IXOTH & st.st_mode)); assert_se(unlink(dst_file) == 0); assert_se(rmdir(dst_dir) == 0); assert_se(stat(src_file, &st) == 0); assert_se(make_mount_point_inode_from_stat(&st, dst_file, 0755) >= 0); assert_se(stat(src_dir, &st) == 0); assert_se(make_mount_point_inode_from_stat(&st, dst_dir, 0755) >= 0); assert_se(stat(dst_dir, &st) == 0); assert_se(S_ISDIR(st.st_mode)); assert_se(stat(dst_file, &st) == 0); assert_se(S_ISREG(st.st_mode)); assert_se(!(S_IXUSR & st.st_mode)); assert_se(!(S_IXGRP & st.st_mode)); assert_se(!(S_IXOTH & st.st_mode)); } TEST(make_mount_switch_root) { _cleanup_(rm_rf_physical_and_freep) char *t = NULL; _cleanup_free_ char *s = NULL; int r; if (geteuid() != 0 || have_effective_cap(CAP_SYS_ADMIN) <= 0) { (void) log_tests_skipped("not running privileged"); return; } assert_se(mkdtemp_malloc(NULL, &t) >= 0); assert_se(asprintf(&s, "%s/somerandomname%" PRIu64, t, random_u64()) >= 0); assert_se(s); assert_se(touch(s) >= 0); for (int force_ms_move = 0; force_ms_move < 2; force_ms_move++) { r = safe_fork("(switch-root)", FORK_RESET_SIGNALS | FORK_CLOSE_ALL_FDS | FORK_DEATHSIG_SIGTERM | FORK_WAIT | FORK_REOPEN_LOG | FORK_LOG | FORK_NEW_MOUNTNS | FORK_MOUNTNS_SLAVE, NULL); assert_se(r >= 0); if (r == 0) { assert_se(make_mount_point(t) >= 0); assert_se(mount_switch_root_full(t, /* mount_propagation_flag= */ 0, force_ms_move) >= 0); assert_se(access(ASSERT_PTR(strrchr(s, '/')), F_OK) >= 0); /* absolute */ assert_se(access(ASSERT_PTR(strrchr(s, '/')) + 1, F_OK) >= 0); /* relative */ assert_se(access(s, F_OK) < 0 && errno == ENOENT); /* doesn't exist in our new environment */ _exit(EXIT_SUCCESS); } } } TEST(umount_recursive) { static const struct { const char *prefix; const char * const keep[3]; } test_table[] = { { .prefix = NULL, .keep = {}, }, { .prefix = "/run", .keep = {}, }, { .prefix = NULL, .keep = { "/dev/shm", NULL }, }, { .prefix = "/dev", .keep = { "/dev/pts", "/dev/shm", NULL }, }, }; int r; FOREACH_ARRAY(t, test_table, ELEMENTSOF(test_table)) { r = safe_fork("(umount-rec)", FORK_RESET_SIGNALS | FORK_CLOSE_ALL_FDS | FORK_DEATHSIG_SIGTERM | FORK_WAIT | FORK_REOPEN_LOG | FORK_LOG | FORK_NEW_MOUNTNS | FORK_MOUNTNS_SLAVE, NULL); if (ERRNO_IS_NEG_PRIVILEGE(r)) return (void) log_notice("Skipping umount_recursive() test, lacking privileges"); assert_se(r >= 0); if (r == 0) { /* child */ _cleanup_(mnt_free_tablep) struct libmnt_table *table = NULL; _cleanup_(mnt_free_iterp) struct libmnt_iter *iter = NULL; _cleanup_fclose_ FILE *f = NULL; _cleanup_free_ char *k = NULL; /* Open /p/s/m file before we unmount everything (which might include /proc/) */ f = fopen("/proc/self/mountinfo", "re"); if (!f) { log_error_errno(errno, "Failed to open /proc/self/mountinfo: %m"); _exit(EXIT_FAILURE); } assert_se(k = strv_join((char**) t->keep, " ")); log_info("detaching just %s (keep: %s)", strna(t->prefix), strna(empty_to_null(k))); assert_se(umount_recursive_full(t->prefix, MNT_DETACH, (char**) t->keep) >= 0); r = libmount_parse("/proc/self/mountinfo", f, &table, &iter); if (r < 0) { log_error_errno(r, "Failed to parse /proc/self/mountinfo: %m"); _exit(EXIT_FAILURE); } for (;;) { struct libmnt_fs *fs; r = mnt_table_next_fs(table, iter, &fs); if (r == 1) break; if (r < 0) { log_error_errno(r, "Failed to get next entry from /proc/self/mountinfo: %m"); _exit(EXIT_FAILURE); } log_debug("left after complete umount: %s", mnt_fs_get_target(fs)); } _exit(EXIT_SUCCESS); } } } TEST(fd_make_mount_point) { _cleanup_(rm_rf_physical_and_freep) char *t = NULL; _cleanup_free_ char *s = NULL; int r; if (geteuid() != 0 || have_effective_cap(CAP_SYS_ADMIN) <= 0) { (void) log_tests_skipped("not running privileged"); return; } assert_se(mkdtemp_malloc(NULL, &t) >= 0); assert_se(asprintf(&s, "%s/somerandomname%" PRIu64, t, random_u64()) >= 0); assert_se(s); assert_se(mkdir(s, 0700) >= 0); r = safe_fork("(make_mount-point)", FORK_RESET_SIGNALS | FORK_CLOSE_ALL_FDS | FORK_DEATHSIG_SIGTERM | FORK_WAIT | FORK_REOPEN_LOG | FORK_LOG | FORK_NEW_MOUNTNS | FORK_MOUNTNS_SLAVE, NULL); assert_se(r >= 0); if (r == 0) { _cleanup_close_ int fd = -EBADF, fd2 = -EBADF; fd = open(s, O_PATH|O_CLOEXEC); assert_se(fd >= 0); assert_se(fd_is_mount_point(fd, NULL, AT_SYMLINK_FOLLOW) == 0); assert_se(fd_make_mount_point(fd) > 0); /* Reopen the inode so that we end up on the new mount */ fd2 = open(s, O_PATH|O_CLOEXEC); assert_se(fd_is_mount_point(fd2, NULL, AT_SYMLINK_FOLLOW) > 0); assert_se(fd_make_mount_point(fd2) == 0); _exit(EXIT_SUCCESS); } } TEST(bind_mount_submounts) { _cleanup_(rmdir_and_freep) char *a = NULL, *b = NULL; _cleanup_free_ char *x = NULL; int r; assert_se(mkdtemp_malloc(NULL, &a) >= 0); r = mount_nofollow_verbose(LOG_INFO, "tmpfs", a, "tmpfs", 0, NULL); if (ERRNO_IS_NEG_PRIVILEGE(r)) return (void) log_tests_skipped("Skipping bind_mount_submounts() test, lacking privileges"); assert_se(r >= 0); assert_se(x = path_join(a, "foo")); assert_se(touch(x) >= 0); free(x); assert_se(x = path_join(a, "x")); assert_se(mkdir(x, 0755) >= 0); assert_se(mount_nofollow_verbose(LOG_INFO, "tmpfs", x, "tmpfs", 0, NULL) >= 0); free(x); assert_se(x = path_join(a, "x/xx")); assert_se(touch(x) >= 0); free(x); assert_se(x = path_join(a, "y")); assert_se(mkdir(x, 0755) >= 0); assert_se(mount_nofollow_verbose(LOG_INFO, "tmpfs", x, "tmpfs", 0, NULL) >= 0); free(x); assert_se(x = path_join(a, "y/yy")); assert_se(touch(x) >= 0); free(x); assert_se(mkdtemp_malloc(NULL, &b) >= 0); assert_se(mount_nofollow_verbose(LOG_INFO, "tmpfs", b, "tmpfs", 0, NULL) >= 0); assert_se(x = path_join(b, "x")); assert_se(mkdir(x, 0755) >= 0); free(x); assert_se(x = path_join(b, "y")); assert_se(mkdir(x, 0755) >= 0); free(x); assert_se(bind_mount_submounts(a, b) >= 0); assert_se(x = path_join(b, "foo")); assert_se(access(x, F_OK) < 0 && errno == ENOENT); free(x); assert_se(x = path_join(b, "x/xx")); assert_se(access(x, F_OK) >= 0); free(x); assert_se(x = path_join(b, "y/yy")); assert_se(access(x, F_OK) >= 0); free(x); assert_se(x = path_join(b, "x")); assert_se(path_is_mount_point(x, NULL, 0) > 0); free(x); assert_se(x = path_join(b, "y")); assert_se(path_is_mount_point(x, NULL, 0) > 0); assert_se(umount_recursive(a, 0) >= 0); assert_se(umount_recursive(b, 0) >= 0); } DEFINE_TEST_MAIN(LOG_DEBUG);