/* SPDX-License-Identifier: LGPL-2.1-or-later */ #include #include #include #include "alloc-util.h" #include "bus-error.h" #include "bus-locator.h" #include "bus-unit-util.h" #include "chase.h" #include "creds-util.h" #include "efi-loader.h" #include "env-util.h" #include "fd-util.h" #include "fileio.h" #include "fstab-util.h" #include "generator.h" #include "in-addr-util.h" #include "initrd-util.h" #include "log.h" #include "main-func.h" #include "mkdir.h" #include "mount-setup.h" #include "mount-util.h" #include "mountpoint-util.h" #include "nulstr-util.h" #include "parse-util.h" #include "path-util.h" #include "proc-cmdline.h" #include "process-util.h" #include "special.h" #include "specifier.h" #include "stat-util.h" #include "string-util.h" #include "strv.h" #include "unit-name.h" #include "virt.h" #include "volatile-util.h" typedef enum MountPointFlags { MOUNT_NOAUTO = 1 << 0, MOUNT_NOFAIL = 1 << 1, MOUNT_AUTOMOUNT = 1 << 2, MOUNT_MAKEFS = 1 << 3, MOUNT_GROWFS = 1 << 4, MOUNT_RW_ONLY = 1 << 5, MOUNT_PCRFS = 1 << 6, } MountPointFlags; typedef struct Mount { bool for_initrd; char *what; char *where; char *fstype; char *options; } Mount; static void mount_array_free(Mount *mounts, size_t n); static bool arg_sysroot_check = false; static const char *arg_dest = NULL; static const char *arg_dest_late = NULL; static bool arg_fstab_enabled = true; static bool arg_swap_enabled = true; static char *arg_root_what = NULL; static char *arg_root_fstype = NULL; static char *arg_root_options = NULL; static char *arg_root_hash = NULL; static int arg_root_rw = -1; static char *arg_usr_what = NULL; static char *arg_usr_fstype = NULL; static char *arg_usr_options = NULL; static char *arg_usr_hash = NULL; static VolatileMode arg_volatile_mode = _VOLATILE_MODE_INVALID; static bool arg_verity = true; static Mount *arg_mounts = NULL; static size_t arg_n_mounts = 0; STATIC_DESTRUCTOR_REGISTER(arg_root_what, freep); STATIC_DESTRUCTOR_REGISTER(arg_root_fstype, freep); STATIC_DESTRUCTOR_REGISTER(arg_root_options, freep); STATIC_DESTRUCTOR_REGISTER(arg_root_hash, freep); STATIC_DESTRUCTOR_REGISTER(arg_usr_what, freep); STATIC_DESTRUCTOR_REGISTER(arg_usr_fstype, freep); STATIC_DESTRUCTOR_REGISTER(arg_usr_options, freep); STATIC_DESTRUCTOR_REGISTER(arg_usr_hash, freep); STATIC_ARRAY_DESTRUCTOR_REGISTER(arg_mounts, arg_n_mounts, mount_array_free); static void mount_done(Mount *m) { assert(m); free(m->what); free(m->where); free(m->fstype); free(m->options); } static void mount_array_free(Mount *mounts, size_t n) { FOREACH_ARRAY(m, mounts, n) mount_done(m); free(mounts); } static int mount_array_add_internal( bool for_initrd, char *in_what, char *in_where, const char *in_fstype, const char *in_options) { _cleanup_free_ char *what = NULL, *where = NULL, *fstype = NULL, *options = NULL; int r; /* This takes what and where. */ what = ASSERT_PTR(in_what); where = in_where; fstype = strdup(isempty(in_fstype) ? "auto" : in_fstype); if (!fstype) return -ENOMEM; if (streq(fstype, "swap")) where = mfree(where); if (!isempty(in_options)) { _cleanup_strv_free_ char **options_strv = NULL; r = strv_split_full(&options_strv, in_options, ",", 0); if (r < 0) return r; r = strv_make_nulstr(options_strv, &options, NULL); } else r = strv_make_nulstr(STRV_MAKE("defaults"), &options, NULL); if (r < 0) return r; if (!GREEDY_REALLOC(arg_mounts, arg_n_mounts + 1)) return -ENOMEM; arg_mounts[arg_n_mounts++] = (Mount) { .for_initrd = for_initrd, .what = TAKE_PTR(what), .where = TAKE_PTR(where), .fstype = TAKE_PTR(fstype), .options = TAKE_PTR(options), }; return 0; } static int mount_array_add(bool for_initrd, const char *str) { _cleanup_free_ char *what = NULL, *where = NULL, *fstype = NULL, *options = NULL; int r; assert(str); r = extract_many_words(&str, ":", EXTRACT_CUNESCAPE | EXTRACT_DONT_COALESCE_SEPARATORS, &what, &where, &fstype, &options, NULL); if (r < 0) return r; if (r < 2) return -EINVAL; if (!isempty(str)) return -EINVAL; return mount_array_add_internal(for_initrd, TAKE_PTR(what), TAKE_PTR(where), fstype, options); } static int mount_array_add_swap(bool for_initrd, const char *str) { _cleanup_free_ char *what = NULL, *options = NULL; int r; assert(str); r = extract_many_words(&str, ":", EXTRACT_CUNESCAPE | EXTRACT_DONT_COALESCE_SEPARATORS, &what, &options, NULL); if (r < 0) return r; if (r < 1) return -EINVAL; if (!isempty(str)) return -EINVAL; return mount_array_add_internal(for_initrd, TAKE_PTR(what), NULL, "swap", options); } static int write_options(FILE *f, const char *options) { _cleanup_free_ char *o = NULL; if (isempty(options)) return 0; if (streq(options, "defaults")) return 0; o = specifier_escape(options); if (!o) return log_oom(); fprintf(f, "Options=%s\n", o); return 1; } static int write_what(FILE *f, const char *what) { _cleanup_free_ char *w = NULL; w = specifier_escape(what); if (!w) return log_oom(); fprintf(f, "What=%s\n", w); return 1; } static int add_swap( const char *source, const char *what, const char *options, MountPointFlags flags) { _cleanup_free_ char *name = NULL; _cleanup_fclose_ FILE *f = NULL; int r; assert(what); if (access("/proc/swaps", F_OK) < 0) { log_info("Swap not supported, ignoring swap entry for %s.", what); return 0; } if (detect_container() > 0) { log_info("Running in a container, ignoring swap entry for %s.", what); return 0; } if (arg_sysroot_check) { log_info("%s should be enabled in the initrd, will request daemon-reload.", what); return true; } log_debug("Found swap entry what=%s makefs=%s growfs=%s pcrfs=%s noauto=%s nofail=%s", what, yes_no(flags & MOUNT_MAKEFS), yes_no(flags & MOUNT_GROWFS), yes_no(flags & MOUNT_PCRFS), yes_no(flags & MOUNT_NOAUTO), yes_no(flags & MOUNT_NOFAIL)); r = unit_name_from_path(what, ".swap", &name); if (r < 0) return log_error_errno(r, "Failed to generate unit name: %m"); r = generator_open_unit_file(arg_dest, source, name, &f); if (r < 0) return r; fprintf(f, "[Unit]\n" "Documentation=man:fstab(5) man:systemd-fstab-generator(8)\n" "SourcePath=%s\n", source); r = generator_write_blockdev_dependency(f, what); if (r < 0) return r; fprintf(f, "\n" "[Swap]\n"); r = write_what(f, what); if (r < 0) return r; r = write_options(f, options); if (r < 0) return r; r = fflush_and_check(f); if (r < 0) return log_error_errno(r, "Failed to write unit file %s: %m", name); /* use what as where, to have a nicer error message */ r = generator_write_timeouts(arg_dest, what, what, options, NULL); if (r < 0) return r; if (flags & MOUNT_MAKEFS) { r = generator_hook_up_mkswap(arg_dest, what); if (r < 0) return r; } if (flags & MOUNT_GROWFS) /* TODO: swap devices must be wiped and recreated */ log_warning("%s: growing swap devices is currently unsupported.", what); if (flags & MOUNT_PCRFS) log_warning("%s: measuring swap devices is currently unsupported.", what); if (!(flags & MOUNT_NOAUTO)) { r = generator_add_symlink(arg_dest, SPECIAL_SWAP_TARGET, (flags & MOUNT_NOFAIL) ? "wants" : "requires", name); if (r < 0) return r; } return true; } static bool mount_is_network(const char *fstype, const char *options) { return fstab_test_option(options, "_netdev\0") || (fstype && fstype_is_network(fstype)); } static bool mount_in_initrd(const char *where, const char *options, bool accept_root) { return fstab_test_option(options, "x-initrd.mount\0") || (where && PATH_IN_SET(where, "/usr", accept_root ? "/" : NULL)); } static int write_timeout( FILE *f, const char *where, const char *opts, const char *filter, const char *variable) { _cleanup_free_ char *timeout = NULL; usec_t u; int r; r = fstab_filter_options(opts, filter, NULL, &timeout, NULL, NULL); if (r < 0) return log_warning_errno(r, "Failed to parse options: %m"); if (r == 0) return 0; r = parse_sec_fix_0(timeout, &u); if (r < 0) { log_warning("Failed to parse timeout for %s, ignoring: %s", where, timeout); return 0; } fprintf(f, "%s=%s\n", variable, FORMAT_TIMESPAN(u, 0)); return 0; } static int write_idle_timeout(FILE *f, const char *where, const char *opts) { return write_timeout(f, where, opts, "x-systemd.idle-timeout\0", "TimeoutIdleSec"); } static int write_mount_timeout(FILE *f, const char *where, const char *opts) { return write_timeout(f, where, opts, "x-systemd.mount-timeout\0", "TimeoutSec"); } static int write_dependency( FILE *f, const char *opts, const char *filter, const char *format) { _cleanup_strv_free_ char **names = NULL, **units = NULL; _cleanup_free_ char *res = NULL; int r; assert(f); assert(opts); r = fstab_filter_options(opts, filter, NULL, NULL, &names, NULL); if (r < 0) return log_warning_errno(r, "Failed to parse options: %m"); if (r == 0) return 0; STRV_FOREACH(s, names) { char *x; r = unit_name_mangle_with_suffix(*s, "as dependency", 0, ".mount", &x); if (r < 0) return log_error_errno(r, "Failed to generate unit name: %m"); r = strv_consume(&units, x); if (r < 0) return log_oom(); } if (units) { res = strv_join(units, " "); if (!res) return log_oom(); DISABLE_WARNING_FORMAT_NONLITERAL; fprintf(f, format, res); REENABLE_WARNING; } return 0; } static int write_after(FILE *f, const char *opts) { return write_dependency(f, opts, "x-systemd.after\0", "After=%1$s\n"); } static int write_requires_after(FILE *f, const char *opts) { return write_dependency(f, opts, "x-systemd.requires\0", "After=%1$s\nRequires=%1$s\n"); } static int write_before(FILE *f, const char *opts) { return write_dependency(f, opts, "x-systemd.before\0", "Before=%1$s\n"); } static int write_requires_mounts_for(FILE *f, const char *opts) { _cleanup_strv_free_ char **paths = NULL, **paths_escaped = NULL; _cleanup_free_ char *res = NULL; int r; assert(f); assert(opts); r = fstab_filter_options(opts, "x-systemd.requires-mounts-for\0", NULL, NULL, &paths, NULL); if (r < 0) return log_warning_errno(r, "Failed to parse options: %m"); if (r == 0) return 0; r = specifier_escape_strv(paths, &paths_escaped); if (r < 0) return log_error_errno(r, "Failed to escape paths: %m"); res = strv_join(paths_escaped, " "); if (!res) return log_oom(); fprintf(f, "RequiresMountsFor=%s\n", res); return 0; } static int write_extra_dependencies(FILE *f, const char *opts) { int r; assert(f); if (opts) { r = write_after(f, opts); if (r < 0) return r; r = write_requires_after(f, opts); if (r < 0) return r; r = write_before(f, opts); if (r < 0) return r; r = write_requires_mounts_for(f, opts); if (r < 0) return r; } return 0; } static int mandatory_mount_drop_unapplicable_options( MountPointFlags *flags, const char *where, const char *options, char **ret_options) { int r; assert(flags); assert(where); assert(options); assert(ret_options); if (!(*flags & (MOUNT_NOAUTO|MOUNT_NOFAIL|MOUNT_AUTOMOUNT))) { _cleanup_free_ char *opts = NULL; opts = strdup(options); if (!opts) return -ENOMEM; *ret_options = TAKE_PTR(opts); return 0; } log_debug("Mount '%s' is mandatory, ignoring 'noauto', 'nofail', and 'x-systemd.automount' options.", where); *flags &= ~(MOUNT_NOAUTO|MOUNT_NOFAIL|MOUNT_AUTOMOUNT); r = fstab_filter_options(options, "noauto\0nofail\0x-systemd.automount\0", NULL, NULL, NULL, ret_options); if (r < 0) return r; return 1; } static int add_mount( const char *source, const char *dest, const char *what, const char *where, const char *original_where, const char *fstype, const char *opts, int passno, MountPointFlags flags, const char *target_unit) { _cleanup_free_ char *name = NULL, *automount_name = NULL, *filtered = NULL, *where_escaped = NULL, *opts_root_filtered = NULL; _cleanup_strv_free_ char **wanted_by = NULL, **required_by = NULL; _cleanup_fclose_ FILE *f = NULL; int r; assert(what); assert(where); assert(opts); assert(target_unit); assert(source); if (streq_ptr(fstype, "autofs")) return 0; if (!is_path(where)) { log_warning("Mount point %s is not a valid path, ignoring.", where); return 0; } if (mount_point_is_api(where) || mount_point_ignore(where)) return 0; if (arg_sysroot_check) { log_info("%s should be mounted in the initrd, will request daemon-reload.", where); return true; } r = fstab_filter_options(opts, "x-systemd.wanted-by\0", NULL, NULL, &wanted_by, NULL); if (r < 0) return r; r = fstab_filter_options(opts, "x-systemd.required-by\0", NULL, NULL, &required_by, NULL); if (r < 0) return r; if (path_equal(where, "/")) { r = mandatory_mount_drop_unapplicable_options(&flags, where, opts, &opts_root_filtered); if (r < 0) return r; opts = opts_root_filtered; if (!strv_isempty(wanted_by)) log_debug("Ignoring 'x-systemd.wanted-by=' option for root device."); if (!strv_isempty(required_by)) log_debug("Ignoring 'x-systemd.required-by=' option for root device."); required_by = strv_free(required_by); wanted_by = strv_free(wanted_by); } r = unit_name_from_path(where, ".mount", &name); if (r < 0) return log_error_errno(r, "Failed to generate unit name: %m"); r = generator_open_unit_file(dest, source, name, &f); if (r < 0) return r; fprintf(f, "[Unit]\n" "Documentation=man:fstab(5) man:systemd-fstab-generator(8)\n" "SourcePath=%s\n", source); if (STRPTR_IN_SET(fstype, "nfs", "nfs4") && !(flags & MOUNT_AUTOMOUNT) && fstab_test_yes_no_option(opts, "bg\0" "fg\0")) { /* The default retry timeout that mount.nfs uses for 'bg' mounts * is 10000 minutes, where as it uses 2 minutes for 'fg' mounts. * As we are making 'bg' mounts look like an 'fg' mount to * mount.nfs (so systemd can manage the job-control aspects of 'bg'), * we need to explicitly preserve that default, and also ensure * the systemd mount-timeout doesn't interfere. * By placing these options first, they can be overridden by * settings in /etc/fstab. */ opts = strjoina("x-systemd.mount-timeout=infinity,retry=10000,nofail,", opts, ",fg"); SET_FLAG(flags, MOUNT_NOFAIL, true); } r = write_extra_dependencies(f, opts); if (r < 0) return r; /* Order the mount unit we generate relative to target_unit, so that DefaultDependencies= on the * target unit won't affect us. */ if (!FLAGS_SET(flags, MOUNT_NOFAIL)) fprintf(f, "Before=%s\n", target_unit); if (passno != 0) { r = generator_write_fsck_deps(f, dest, what, where, fstype); if (r < 0) return r; } r = generator_write_blockdev_dependency(f, what); if (r < 0) return r; fprintf(f, "\n" "[Mount]\n"); r = write_what(f, what); if (r < 0) return r; if (original_where) fprintf(f, "# Canonicalized from %s\n", original_where); where_escaped = specifier_escape(where); if (!where_escaped) return log_oom(); fprintf(f, "Where=%s\n", where_escaped); if (!isempty(fstype) && !streq(fstype, "auto")) { _cleanup_free_ char *t = NULL; t = specifier_escape(fstype); if (!t) return -ENOMEM; fprintf(f, "Type=%s\n", t); } r = generator_write_timeouts(dest, what, where, opts, &filtered); if (r < 0) return r; r = generator_write_device_deps(dest, what, where, opts); if (r < 0) return r; if (in_initrd() && path_equal(where, "/sysroot") && is_device_path(what)) { r = generator_write_initrd_root_device_deps(dest, what); if (r < 0) return r; } r = write_mount_timeout(f, where, opts); if (r < 0) return r; r = write_options(f, filtered); if (r < 0) return r; if (flags & MOUNT_RW_ONLY) fprintf(f, "ReadWriteOnly=yes\n"); r = fflush_and_check(f); if (r < 0) return log_error_errno(r, "Failed to write unit file %s: %m", name); if (flags & MOUNT_MAKEFS) { r = generator_hook_up_mkfs(dest, what, where, fstype); if (r < 0) return r; } if (flags & MOUNT_GROWFS) { r = generator_hook_up_growfs(dest, where, target_unit); if (r < 0) return r; } if (flags & MOUNT_PCRFS) { r = efi_measured_uki(LOG_WARNING); if (r == 0) log_debug("Kernel stub did not measure kernel image into PCR, skipping userspace measurement, too."); else if (r > 0) { r = generator_hook_up_pcrfs(dest, where, target_unit); if (r < 0) return r; } } if (!FLAGS_SET(flags, MOUNT_AUTOMOUNT)) { if (!FLAGS_SET(flags, MOUNT_NOAUTO) && strv_isempty(wanted_by) && strv_isempty(required_by)) { r = generator_add_symlink(dest, target_unit, (flags & MOUNT_NOFAIL) ? "wants" : "requires", name); if (r < 0) return r; } else { STRV_FOREACH(s, wanted_by) { r = generator_add_symlink(dest, *s, "wants", name); if (r < 0) return r; } STRV_FOREACH(s, required_by) { r = generator_add_symlink(dest, *s, "requires", name); if (r < 0) return r; } } } else { r = unit_name_from_path(where, ".automount", &automount_name); if (r < 0) return log_error_errno(r, "Failed to generate unit name: %m"); f = safe_fclose(f); r = generator_open_unit_file(dest, source, automount_name, &f); if (r < 0) return r; fprintf(f, "[Unit]\n" "SourcePath=%s\n" "Documentation=man:fstab(5) man:systemd-fstab-generator(8)\n", source); fprintf(f, "\n" "[Automount]\n" "Where=%s\n", where_escaped); r = write_idle_timeout(f, where, opts); if (r < 0) return r; r = fflush_and_check(f); if (r < 0) return log_error_errno(r, "Failed to write unit file %s: %m", automount_name); r = generator_add_symlink(dest, target_unit, (flags & MOUNT_NOFAIL) ? "wants" : "requires", automount_name); if (r < 0) return r; } return true; } static int do_daemon_reload(void) { _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL; _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL; int r, k; log_debug("Calling org.freedesktop.systemd1.Manager.Reload()..."); r = bus_connect_system_systemd(&bus); if (r < 0) return log_error_errno(r, "Failed to get D-Bus connection: %m"); r = bus_service_manager_reload(bus); if (r < 0) return r; /* We need to requeue the two targets so that any new units which previously were not part of the * targets, and which we now added, will be started. */ r = 0; FOREACH_STRING(unit, SPECIAL_INITRD_FS_TARGET, SPECIAL_SWAP_TARGET) { log_info("Requesting %s/start/replace...", unit); k = bus_call_method(bus, bus_systemd_mgr, "StartUnit", &error, NULL, "ss", unit, "replace"); if (k < 0) { log_error_errno(k, "Failed to (re)start %s: %s", unit, bus_error_message(&error, r)); RET_GATHER(r, k); } } return r; } static const char* sysroot_fstab_path(void) { return getenv("SYSTEMD_SYSROOT_FSTAB") ?: "/sysroot/etc/fstab"; } static bool sysfs_check(void) { static int cached = -1; int r; if (cached < 0) { r = getenv_bool_secure("SYSTEMD_SYSFS_CHECK"); if (r < 0 && r != -ENXIO) log_debug_errno(r, "Failed to parse $SYSTEMD_SYSFS_CHECK, ignoring: %m"); cached = r != 0; } return cached; } static int add_sysusr_sysroot_usr_bind_mount(const char *source) { return add_mount(source, arg_dest, "/sysusr/usr", "/sysroot/usr", NULL, NULL, "bind", 0, 0, SPECIAL_INITRD_FS_TARGET); } static MountPointFlags fstab_options_to_flags(const char *options, bool is_swap) { MountPointFlags flags = 0; if (fstab_test_option(options, "x-systemd.makefs\0")) flags |= MOUNT_MAKEFS; if (fstab_test_option(options, "x-systemd.growfs\0")) flags |= MOUNT_GROWFS; if (fstab_test_option(options, "x-systemd.pcrfs\0")) flags |= MOUNT_PCRFS; if (fstab_test_yes_no_option(options, "noauto\0" "auto\0")) flags |= MOUNT_NOAUTO; if (fstab_test_yes_no_option(options, "nofail\0" "fail\0")) flags |= MOUNT_NOFAIL; if (!is_swap) { if (fstab_test_option(options, "x-systemd.rw-only\0")) flags |= MOUNT_RW_ONLY; if (fstab_test_option(options, "comment=systemd.automount\0" "x-systemd.automount\0")) flags |= MOUNT_AUTOMOUNT; } return flags; } static int canonicalize_mount_path(const char *path, const char *type, bool prefix_sysroot, char **ret) { _cleanup_free_ char *p = NULL; bool changed; int r; assert(path); assert(type); assert(STR_IN_SET(type, "where", "what")); assert(ret); // FIXME: when chase() learns to chase non-existent paths, use this here and drop the prefixing with // /sysroot on error below. r = chase(path, prefix_sysroot ? "/sysroot" : NULL, CHASE_PREFIX_ROOT | CHASE_NONEXISTENT, &p, NULL); if (r < 0) { log_debug_errno(r, "Failed to chase '%s', using as-is: %m", path); if (prefix_sysroot) p = path_join("/sysroot", path); else p = strdup(path); if (!p) return log_oom(); path_simplify(p); } changed = !streq(path, p); if (changed) log_debug("Canonicalized %s=%s to %s", type, path, p); *ret = TAKE_PTR(p); return changed; } static int parse_fstab_one( const char *source, const char *what_original, const char *where_original, const char *fstype, const char *options, int passno, bool prefix_sysroot, bool accept_root, /* This takes an effect only when prefix_sysroot is true. */ bool use_swap_enabled) { _cleanup_free_ char *what = NULL, *where = NULL, *opts = NULL; MountPointFlags flags; bool is_swap, where_changed; int r; assert(what_original); assert(fstype); assert(options); if (prefix_sysroot && !mount_in_initrd(where_original, options, accept_root)) return 0; is_swap = streq_ptr(fstype, "swap"); if (is_swap && use_swap_enabled && !arg_swap_enabled) { log_info("Swap unit generation disabled on kernel command line, ignoring swap entry for %s.", what_original); return 0; } what = fstab_node_to_udev_node(what_original); if (!what) return log_oom(); if (path_is_read_only_fs("/sys") > 0 && (streq(what, "sysfs") || (sysfs_check() && is_device_path(what)))) { log_info("/sys/ is read-only (running in a container?), ignoring mount for %s.", what); return 0; } flags = fstab_options_to_flags(options, is_swap); if (is_swap) return add_swap(source, what, options, flags); if (passno < 0) passno = is_device_path(what); assert(where_original); /* 'where' is not necessary for swap entry. */ if (!is_path(where_original)) { log_warning("Mount point %s is not a valid path, ignoring.", where_original); return 0; } /* Follow symlinks here; see 5261ba901845c084de5a8fd06500ed09bfb0bd80 which makes sense for * mount units, but causes problems since it historically worked to have symlinks in e.g. * /etc/fstab. So we canonicalize here. Note that we use CHASE_NONEXISTENT to handle the case * where a symlink refers to another mount target; this works assuming the sub-mountpoint * target is the final directory. */ r = canonicalize_mount_path(where_original, "where", prefix_sysroot, &where); if (r < 0) return r; where_changed = r > 0; if (prefix_sysroot && fstab_is_bind(options, fstype)) { /* When in initrd, the source of bind mount needs to be prepended with /sysroot as well. */ _cleanup_free_ char *p = NULL; r = canonicalize_mount_path(what, "what", prefix_sysroot, &p); if (r < 0) return r; free_and_replace(what, p); } log_debug("Found entry what=%s where=%s type=%s makefs=%s growfs=%s pcrfs=%s noauto=%s nofail=%s", what, where, strna(fstype), yes_no(flags & MOUNT_MAKEFS), yes_no(flags & MOUNT_GROWFS), yes_no(flags & MOUNT_PCRFS), yes_no(flags & MOUNT_NOAUTO), yes_no(flags & MOUNT_NOFAIL)); bool is_sysroot = in_initrd() && path_equal(where, "/sysroot"); /* See comment from add_sysroot_usr_mount() about the need for extra indirection in case /usr needs * to be mounted in order for the root fs to be synthesized based on configuration included in /usr/, * e.g. systemd-repart. */ bool is_sysroot_usr = in_initrd() && path_equal(where, "/sysroot/usr"); const char *target_unit = is_sysroot ? SPECIAL_INITRD_ROOT_FS_TARGET : is_sysroot_usr ? SPECIAL_INITRD_USR_FS_TARGET : prefix_sysroot ? SPECIAL_INITRD_FS_TARGET : mount_is_network(fstype, options) ? SPECIAL_REMOTE_FS_TARGET : SPECIAL_LOCAL_FS_TARGET; /* nofail, noauto and x-systemd.automount don't make sense for critical filesystems we must mount in initrd. */ if (is_sysroot || is_sysroot_usr) { r = mandatory_mount_drop_unapplicable_options(&flags, where, options, &opts); if (r < 0) return r; options = opts; } r = add_mount(source, arg_dest, what, is_sysroot_usr ? "/sysusr/usr" : where, !is_sysroot_usr && where_changed ? where_original : NULL, fstype, options, passno, flags, target_unit); if (r <= 0) return r; if (is_sysroot_usr) { log_debug("Synthesizing fstab entry what=/sysusr/usr where=/sysroot/usr opts=bind"); r = add_sysusr_sysroot_usr_bind_mount(source); if (r < 0) return r; } return true; } static int parse_fstab(bool prefix_sysroot) { _cleanup_endmntent_ FILE *f = NULL; const char *fstab; struct mntent *me; int r, ret = 0; if (prefix_sysroot) fstab = sysroot_fstab_path(); else { fstab = fstab_path(); assert(!arg_sysroot_check); } log_debug("Parsing %s...", fstab); f = setmntent(fstab, "re"); if (!f) { if (errno == ENOENT) return 0; return log_error_errno(errno, "Failed to open %s: %m", fstab); } while ((me = getmntent(f))) { r = parse_fstab_one(fstab, me->mnt_fsname, me->mnt_dir, me->mnt_type, me->mnt_opts, me->mnt_passno, prefix_sysroot, /* accept_root = */ false, /* use_swap_enabled = */ true); if (r < 0 && ret >= 0) ret = r; if (arg_sysroot_check && r > 0) return true; /* We found a mount or swap that would be started… */ } return ret; } static int sysroot_is_nfsroot(void) { union in_addr_union u; const char *sep, *a; int r; assert(arg_root_what); /* From dracut.cmdline(7). * * root=[:][:] * root=nfs:[:][:], * root=nfs4:[:][:], * root={dhcp|dhcp6} * * mount nfs share from :/, if no server-ip is given, use dhcp next_server. * If server-ip is an IPv6 address it has to be put in brackets, e.g. [2001:DB8::1]. NFS options * can be appended with the prefix ":" or "," and are separated by ",". */ if (path_equal(arg_root_what, "/dev/nfs") || STR_IN_SET(arg_root_what, "dhcp", "dhcp6") || STARTSWITH_SET(arg_root_what, "nfs:", "nfs4:")) return true; /* IPv6 address */ if (arg_root_what[0] == '[') { sep = strchr(arg_root_what + 1, ']'); if (!sep) return -EINVAL; a = strndupa_safe(arg_root_what + 1, sep - arg_root_what - 1); r = in_addr_from_string(AF_INET6, a, &u); if (r < 0) return r; return true; } /* IPv4 address */ sep = strchr(arg_root_what, ':'); if (sep) { a = strndupa_safe(arg_root_what, sep - arg_root_what); if (in_addr_from_string(AF_INET, a, &u) >= 0) return true; } /* root directory without address */ return path_is_absolute(arg_root_what) && !path_startswith(arg_root_what, "/dev"); } static int add_sysroot_mount(void) { _cleanup_free_ char *what = NULL; const char *opts, *fstype; bool default_rw, makefs; MountPointFlags flags; int r; if (isempty(arg_root_what)) { log_debug("Could not find a root= entry on the kernel command line."); return 0; } if (streq(arg_root_what, "gpt-auto")) { /* This is handled by gpt-auto-generator */ log_debug("Skipping root directory handling, as gpt-auto was requested."); return 0; } else if (streq(arg_root_what, "fstab")) { /* This is handled by parse_fstab */ log_debug("Using initrd's fstab for /sysroot/ configuration."); return 0; } r = sysroot_is_nfsroot(); if (r < 0) log_debug_errno(r, "Failed to determine if the root directory is on NFS, assuming not: %m"); else if (r > 0) { /* This is handled by the kernel or the initrd */ log_debug("Skipping root directory handling, as root on NFS was requested."); return 0; } if (startswith(arg_root_what, "cifs://")) { log_debug("Skipping root directory handling, as root on CIFS was requested."); return 0; } if (startswith(arg_root_what, "iscsi:")) { log_debug("Skipping root directory handling, as root on iSCSI was requested."); return 0; } if (startswith(arg_root_what, "live:")) { log_debug("Skipping root directory handling, as root on live image was requested."); return 0; } if (streq(arg_root_what, "tmpfs")) { /* If root=tmpfs is specified, then take this as shortcut for a writable tmpfs mount as root */ what = strdup("rootfs"); /* just a pretty name, to show up in /proc/self/mountinfo */ if (!what) return log_oom(); fstype = arg_root_fstype ?: "tmpfs"; /* tmpfs, unless overridden */ default_rw = true; /* writable, unless overridden */; } else { what = fstab_node_to_udev_node(arg_root_what); if (!what) return log_oom(); fstype = arg_root_fstype; /* if not specified explicitly, don't default to anything here */ default_rw = false; /* read-only, unless overridden */ } if (!arg_root_options) opts = arg_root_rw > 0 || (arg_root_rw < 0 && default_rw) ? "rw" : "ro"; else if (arg_root_rw >= 0 || !fstab_test_option(arg_root_options, "ro\0" "rw\0")) opts = strjoina(arg_root_options, ",", arg_root_rw > 0 ? "rw" : "ro"); else opts = arg_root_options; log_debug("Found entry what=%s where=/sysroot type=%s opts=%s", what, strna(arg_root_fstype), strempty(opts)); makefs = fstab_test_option(opts, "x-systemd.makefs\0"); flags = makefs * MOUNT_MAKEFS; return add_mount("/proc/cmdline", arg_dest, what, "/sysroot", NULL, fstype, opts, is_device_path(what) ? 1 : 0, /* passno */ flags, /* makefs off, pcrfs off, noauto off, nofail off, automount off */ SPECIAL_INITRD_ROOT_FS_TARGET); } static int add_sysroot_usr_mount(void) { _cleanup_free_ char *what = NULL; const char *opts; bool makefs; MountPointFlags flags; int r; /* Returns 0 if we didn't do anything, > 0 if we either generated a unit for the /usr/ mount, or we * know for sure something else did */ if (!arg_usr_what && !arg_usr_fstype && !arg_usr_options) return 0; if (arg_root_what && !arg_usr_what) { /* Copy over the root device, in case the /usr mount just differs in a mount option (consider btrfs subvolumes) */ arg_usr_what = strdup(arg_root_what); if (!arg_usr_what) return log_oom(); } if (arg_root_fstype && !arg_usr_fstype) { arg_usr_fstype = strdup(arg_root_fstype); if (!arg_usr_fstype) return log_oom(); } if (arg_root_options && !arg_usr_options) { arg_usr_options = strdup(arg_root_options); if (!arg_usr_options) return log_oom(); } if (isempty(arg_usr_what)) { log_debug("Could not find a mount.usr= entry on the kernel command line."); return 0; } if (streq(arg_usr_what, "gpt-auto")) { /* This is handled by the gpt-auto generator */ log_debug("Skipping /usr/ directory handling, as gpt-auto was requested."); return 1; /* systemd-gpt-auto-generator will generate a unit for this, hence report that a * unit file is being created for the host /usr/ mount. */ } else if (streq(arg_usr_what, "fstab")) { /* This is handled by parse_fstab */ log_debug("Using initrd's fstab for /sysroot/usr/ configuration."); return 1; /* parse_fstab will generate a unit for this, hence report that a * unit file is being created for the host /usr/ mount. */ } if (path_equal(arg_usr_what, "/dev/nfs")) { /* This is handled by the initrd (if at all supported, that is) */ log_debug("Skipping /usr/ directory handling, as /dev/nfs was requested."); return 1; /* As above, report that NFS code will create the unit */ } what = fstab_node_to_udev_node(arg_usr_what); if (!what) return log_oom(); if (!arg_usr_options) opts = arg_root_rw > 0 ? "rw" : "ro"; else if (!fstab_test_option(arg_usr_options, "ro\0" "rw\0")) opts = strjoina(arg_usr_options, ",", arg_root_rw > 0 ? "rw" : "ro"); else opts = arg_usr_options; /* When mounting /usr from the initrd, we add an extra level of indirection: we first mount the /usr/ * partition to /sysusr/usr/, and then afterwards bind mount that to /sysroot/usr/. We do this so * that we can cover for systems that initially only have a /usr/ around and where the root fs needs * to be synthesized, based on configuration included in /usr/, e.g. systemd-repart. Software like * this should order itself after initrd-usr-fs.target and before initrd-fs.target; and it should * look into both /sysusr/ and /sysroot/ for the configuration data to apply. */ log_debug("Found entry what=%s where=/sysusr/usr type=%s opts=%s", what, strna(arg_usr_fstype), strempty(opts)); makefs = fstab_test_option(opts, "x-systemd.makefs\0"); flags = makefs * MOUNT_MAKEFS; r = add_mount("/proc/cmdline", arg_dest, what, "/sysusr/usr", NULL, arg_usr_fstype, opts, is_device_path(what) ? 1 : 0, /* passno */ flags, SPECIAL_INITRD_USR_FS_TARGET); if (r < 0) return r; log_debug("Synthesizing entry what=/sysusr/usr where=/sysroot/usr opts=bind"); r = add_sysusr_sysroot_usr_bind_mount("/proc/cmdline"); if (r < 0) return r; return 1; } static int add_sysroot_usr_mount_or_fallback(void) { int r; r = add_sysroot_usr_mount(); if (r != 0) return r; /* OK, so we didn't write anything out for /sysusr/usr/ nor /sysroot/usr/. In this case, let's make * sure that initrd-usr-fs.target is at least ordered after sysroot.mount so that services that order * themselves after it get the guarantee that /usr/ is definitely mounted somewhere. */ return generator_add_symlink( arg_dest, SPECIAL_INITRD_USR_FS_TARGET, "requires", "sysroot.mount"); } static int add_volatile_root(void) { /* Let's add in systemd-remount-volatile.service which will remount the root device to tmpfs if this is * requested (or as an overlayfs), leaving only /usr from the root mount inside. */ if (!IN_SET(arg_volatile_mode, VOLATILE_YES, VOLATILE_OVERLAY)) return 0; return generator_add_symlink(arg_dest, SPECIAL_INITRD_ROOT_FS_TARGET, "requires", SYSTEM_DATA_UNIT_DIR "/" SPECIAL_VOLATILE_ROOT_SERVICE); } static int add_volatile_var(void) { if (arg_volatile_mode != VOLATILE_STATE) return 0; /* If requested, mount /var as tmpfs, but do so only if there's nothing else defined for this. */ return add_mount("/proc/cmdline", arg_dest_late, "tmpfs", "/var", NULL, "tmpfs", "mode=0755" TMPFS_LIMITS_VAR, 0, 0, SPECIAL_LOCAL_FS_TARGET); } static int add_mounts_from_cmdline(void) { int r = 0; /* Handle each entries found in cmdline as a fstab entry. */ FOREACH_ARRAY(m, arg_mounts, arg_n_mounts) { if (m->for_initrd && !in_initrd()) continue; RET_GATHER(r, parse_fstab_one("/proc/cmdline", m->what, m->where, m->fstype, m->options, /* passno = */ -1, /* prefix_sysroot = */ !m->for_initrd && in_initrd(), /* accept_root = */ true, /* use_swap_enabled = */ false)); } return r; } static int add_mounts_from_creds(bool prefix_sysroot) { _cleanup_free_ void *b = NULL; struct mntent *me; size_t bs; int r; assert(in_initrd() || !prefix_sysroot); r = read_credential_with_decryption( in_initrd() && !prefix_sysroot ? "fstab.extra.initrd" : "fstab.extra", &b, &bs); if (r <= 0) return r; _cleanup_fclose_ FILE *f = NULL; f = fmemopen_unlocked(b, bs, "r"); if (!f) return log_oom(); r = 0; while ((me = getmntent(f))) RET_GATHER(r, parse_fstab_one("/run/credentials", me->mnt_fsname, me->mnt_dir, me->mnt_type, me->mnt_opts, me->mnt_passno, /* prefix_sysroot = */ prefix_sysroot, /* accept_root = */ true, /* use_swap_enabled = */ true)); return r; } static int parse_proc_cmdline_item(const char *key, const char *value, void *data) { int r; assert(key); /* root=, usr=, usrfstype= and roofstype= may occur more than once, the last * instance should take precedence. In the case of multiple rootflags= * or usrflags= the arguments should be concatenated */ if (STR_IN_SET(key, "fstab", "rd.fstab")) { r = value ? parse_boolean(value) : 1; if (r < 0) log_warning("Failed to parse fstab switch %s. Ignoring.", value); else arg_fstab_enabled = fstab_set_enabled(r); } else if (streq(key, "root")) { if (proc_cmdline_value_missing(key, value)) return 0; return free_and_strdup_warn(&arg_root_what, empty_to_null(value)); } else if (streq(key, "rootfstype")) { if (proc_cmdline_value_missing(key, value)) return 0; return free_and_strdup_warn(&arg_root_fstype, empty_to_null(value)); } else if (streq(key, "rootflags")) { if (proc_cmdline_value_missing(key, value)) return 0; if (!strextend_with_separator(&arg_root_options, ",", value)) return log_oom(); } else if (streq(key, "roothash")) { if (proc_cmdline_value_missing(key, value)) return 0; return free_and_strdup_warn(&arg_root_hash, empty_to_null(value)); } else if (streq(key, "mount.usr")) { if (proc_cmdline_value_missing(key, value)) return 0; return free_and_strdup_warn(&arg_usr_what, empty_to_null(value)); } else if (streq(key, "mount.usrfstype")) { if (proc_cmdline_value_missing(key, value)) return 0; return free_and_strdup_warn(&arg_usr_fstype, empty_to_null(value)); } else if (streq(key, "mount.usrflags")) { if (proc_cmdline_value_missing(key, value)) return 0; if (!strextend_with_separator(&arg_usr_options, ",", value)) return log_oom(); } else if (streq(key, "usrhash")) { if (proc_cmdline_value_missing(key, value)) return 0; return free_and_strdup_warn(&arg_usr_hash, empty_to_null(value)); } else if (streq(key, "rw") && !value) arg_root_rw = true; else if (streq(key, "ro") && !value) arg_root_rw = false; else if (streq(key, "systemd.volatile")) { VolatileMode m; if (value) { m = volatile_mode_from_string(value); if (m < 0) log_warning_errno(m, "Failed to parse systemd.volatile= argument: %s", value); else arg_volatile_mode = m; } else arg_volatile_mode = VOLATILE_YES; } else if (streq(key, "systemd.swap")) { r = value ? parse_boolean(value) : 1; if (r < 0) log_warning("Failed to parse systemd.swap switch %s. Ignoring.", value); else arg_swap_enabled = r; } else if (streq(key, "systemd.verity")) { r = value ? parse_boolean(value) : 1; if (r < 0) log_warning("Failed to parse systemd.verity= kernel command line switch %s. Ignoring.", value); else arg_verity = r; } else if (STR_IN_SET(key, "systemd.mount-extra", "rd.systemd.mount-extra")) { if (proc_cmdline_value_missing(key, value)) return 0; r = mount_array_add(startswith(key, "rd."), value); if (r < 0) log_warning("Failed to parse systemd.mount-extra= option, ignoring: %s", value); } else if (STR_IN_SET(key, "systemd.swap-extra", "rd.systemd.swap-extra")) { if (proc_cmdline_value_missing(key, value)) return 0; r = mount_array_add_swap(startswith(key, "rd."), value); if (r < 0) log_warning("Failed to parse systemd.swap-extra= option, ignoring: %s", value); } return 0; } static int determine_device( char **what, int *rw, char **options, const char *hash, const char *name) { assert(what); assert(name); /* If we have a hash but no device then Verity is used, and we use the DM device. */ if (*what) return 0; if (!hash) return 0; if (!arg_verity) return 0; *what = path_join("/dev/mapper/", name); if (!*what) return log_oom(); /* Verity is always read-only */ if (rw) *rw = false; if (options && !strextend_with_separator(options, ",", "ro")) return log_oom(); log_info("Using verity %s device %s.", name, *what); return 1; } static int determine_root(void) { return determine_device(&arg_root_what, &arg_root_rw, NULL, arg_root_hash, "root"); } static int determine_usr(void) { return determine_device(&arg_usr_what, NULL, &arg_usr_options, arg_usr_hash, "usr"); } /* If arg_sysroot_check is false, run as generator in the usual fashion. * If it is true, check /sysroot/etc/fstab for any units that we'd want to mount * in the initrd, and call daemon-reload. We will get reinvoked as a generator, * with /sysroot/etc/fstab available, and then we can write additional units based * on that file. */ static int run_generator(void) { int r = 0; r = proc_cmdline_parse(parse_proc_cmdline_item, NULL, 0); if (r < 0) log_warning_errno(r, "Failed to parse kernel command line, ignoring: %m"); (void) determine_root(); (void) determine_usr(); if (arg_sysroot_check) { r = parse_fstab(/* prefix_sysroot = */ true); if (r == 0) log_debug("Nothing interesting found, not doing daemon-reload."); if (r > 0) r = do_daemon_reload(); return r; } r = 0; /* Always honour root= and usr= in the kernel command line if we are in an initrd */ if (in_initrd()) { RET_GATHER(r, add_sysroot_mount()); RET_GATHER(r, add_sysroot_usr_mount_or_fallback()); RET_GATHER(r, add_volatile_root()); } else RET_GATHER(r, add_volatile_var()); /* Honour /etc/fstab only when that's enabled */ if (arg_fstab_enabled) { /* Parse the local /etc/fstab, possibly from the initrd */ RET_GATHER(r, parse_fstab(/* prefix_sysroot = */ false)); /* If running in the initrd also parse the /etc/fstab from the host */ if (in_initrd()) RET_GATHER(r, parse_fstab(/* prefix_sysroot = */ true)); else RET_GATHER(r, generator_enable_remount_fs_service(arg_dest)); } RET_GATHER(r, add_mounts_from_cmdline()); RET_GATHER(r, add_mounts_from_creds(/* prefix_sysroot = */ false)); if (in_initrd()) RET_GATHER(r, add_mounts_from_creds(/* prefix_sysroot = */ true)); return r; } static int run(int argc, char **argv) { arg_sysroot_check = invoked_as(argv, "systemd-sysroot-fstab-check"); if (arg_sysroot_check) { /* Run as in systemd-sysroot-fstab-check mode */ log_setup(); if (strv_length(argv) > 1) return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "This program takes no arguments."); if (!in_initrd()) return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "This program is only useful in the initrd."); } else { /* Run in generator mode */ log_setup_generator(); if (!IN_SET(strv_length(argv), 2, 4)) return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "This program takes one or three arguments."); arg_dest = ASSERT_PTR(argv[1]); arg_dest_late = ASSERT_PTR(argv[argc > 3 ? 3 : 1]); } return run_generator(); } DEFINE_MAIN_FUNCTION(run);