X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fcore%2Fshutdown.c;h=4cbdf1258751b8ffb8d1429f415dc572b8bb2a10;hp=2494bb86a120c15bf735e090b453e584156b749c;hb=4968105790c65af58d4ab42bffa2a4bedc0be8ee;hpb=b55d0651c0433aee6bbec0516a0c2eb001c3fc31 diff --git a/src/core/shutdown.c b/src/core/shutdown.c index 2494bb86a..4cbdf1258 100644 --- a/src/core/shutdown.c +++ b/src/core/shutdown.c @@ -24,7 +24,6 @@ #include #include #include -#include #include #include #include @@ -36,329 +35,183 @@ #include #include #include +#include #include "missing.h" #include "log.h" +#include "fileio.h" #include "umount.h" #include "util.h" #include "mkdir.h" #include "virt.h" #include "watchdog.h" +#include "killall.h" +#include "cgroup-util.h" +#include "def.h" +#include "switch-root.h" -#define TIMEOUT_USEC (5 * USEC_PER_SEC) #define FINALIZE_ATTEMPTS 50 -static bool ignore_proc(pid_t pid) { - char buf[PATH_MAX]; - FILE *f; - char c; - size_t count; - uid_t uid; - int r; - - /* We are PID 1, let's not commit suicide */ - if (pid == 1) - return true; - - r = get_process_uid(pid, &uid); - if (r < 0) - return true; /* not really, but better safe than sorry */ - - /* Non-root processes otherwise are always subject to be killed */ - if (uid != 0) - return false; - - snprintf(buf, sizeof(buf), "/proc/%lu/cmdline", (unsigned long) pid); - char_array_0(buf); - - f = fopen(buf, "re"); - if (!f) - return true; /* not really, but has the desired effect */ - - count = fread(&c, 1, 1, f); - fclose(f); - - /* Kernel threads have an empty cmdline */ - if (count <= 0) - return true; - - /* Processes with argv[0][0] = '@' we ignore from the killing - * spree. - * - * http://www.freedesktop.org/wiki/Software/systemd/RootStorageDaemons */ - if (count == 1 && c == '@') - return true; - - return false; -} - -static int killall(int sign) { - DIR *dir; - struct dirent *d; - unsigned int n_processes = 0; - - dir = opendir("/proc"); - if (!dir) - return -errno; - - while ((d = readdir(dir))) { - pid_t pid; - - if (parse_pid(d->d_name, &pid) < 0) - continue; - - if (ignore_proc(pid)) - continue; - - if (kill(pid, sign) == 0) - n_processes++; - else - log_warning("Could not kill %d: %m", pid); - } - - closedir(dir); - - return n_processes; -} - -static void wait_for_children(int n_processes, sigset_t *mask) { - usec_t until; - - assert(mask); - - until = now(CLOCK_MONOTONIC) + TIMEOUT_USEC; - for (;;) { - struct timespec ts; - int k; - usec_t n; - - for (;;) { - pid_t pid = waitpid(-1, NULL, WNOHANG); - - if (pid == 0) - break; - - if (pid < 0 && errno == ECHILD) - return; - - if (n_processes > 0) - if (--n_processes == 0) - return; - } - - n = now(CLOCK_MONOTONIC); - if (n >= until) - return; - - timespec_store(&ts, until - n); - - if ((k = sigtimedwait(mask, NULL, &ts)) != SIGCHLD) { - - if (k < 0 && errno != EAGAIN) { - log_error("sigtimedwait() failed: %m"); - return; - } +static char* arg_verb; - if (k >= 0) - log_warning("sigtimedwait() returned unexpected signal."); - } - } -} +static int parse_argv(int argc, char *argv[]) { + enum { + ARG_LOG_LEVEL = 0x100, + ARG_LOG_TARGET, + ARG_LOG_COLOR, + ARG_LOG_LOCATION, + }; -static void send_signal(int sign) { - sigset_t mask, oldmask; - int n_processes; + static const struct option options[] = { + { "log-level", required_argument, NULL, ARG_LOG_LEVEL }, + { "log-target", required_argument, NULL, ARG_LOG_TARGET }, + { "log-color", optional_argument, NULL, ARG_LOG_COLOR }, + { "log-location", optional_argument, NULL, ARG_LOG_LOCATION }, + {} + }; - assert_se(sigemptyset(&mask) == 0); - assert_se(sigaddset(&mask, SIGCHLD) == 0); - assert_se(sigprocmask(SIG_BLOCK, &mask, &oldmask) == 0); + int c, r; - if (kill(-1, SIGSTOP) < 0 && errno != ESRCH) - log_warning("kill(-1, SIGSTOP) failed: %m"); + assert(argc >= 1); + assert(argv); - n_processes = killall(sign); + /* "-" prevents getopt from permuting argv[] and moving the verb away + * from argv[1]. Our interface to initrd promises it'll be there. */ + while ((c = getopt_long(argc, argv, "-", options, NULL)) >= 0) + switch (c) { - if (kill(-1, SIGCONT) < 0 && errno != ESRCH) - log_warning("kill(-1, SIGCONT) failed: %m"); + case ARG_LOG_LEVEL: + r = log_set_max_level_from_string(optarg); + if (r < 0) + log_error("Failed to parse log level %s, ignoring.", optarg); - if (n_processes <= 0) - goto finish; - - wait_for_children(n_processes, &mask); - -finish: - sigprocmask(SIG_SETMASK, &oldmask, NULL); -} - -static void ultimate_send_signal(int sign) { - sigset_t mask, oldmask; - int r; - - assert_se(sigemptyset(&mask) == 0); - assert_se(sigaddset(&mask, SIGCHLD) == 0); - assert_se(sigprocmask(SIG_BLOCK, &mask, &oldmask) == 0); - - if (kill(-1, SIGSTOP) < 0 && errno != ESRCH) - log_warning("kill(-1, SIGSTOP) failed: %m"); + break; - r = kill(-1, sign); - if (r < 0 && errno != ESRCH) - log_warning("kill(-1, %s) failed: %m", signal_to_string(sign)); + case ARG_LOG_TARGET: + r = log_set_target_from_string(optarg); + if (r < 0) + log_error("Failed to parse log target %s, ignoring", optarg); - if (kill(-1, SIGCONT) < 0 && errno != ESRCH) - log_warning("kill(-1, SIGCONT) failed: %m"); + break; - if (r < 0) - goto finish; + case ARG_LOG_COLOR: - wait_for_children(0, &mask); + if (optarg) { + r = log_show_color_from_string(optarg); + if (r < 0) + log_error("Failed to parse log color setting %s, ignoring", optarg); + } else + log_show_color(true); -finish: - sigprocmask(SIG_SETMASK, &oldmask, NULL); -} + break; -static int prepare_new_root(void) { - static const char dirs[] = - "/run/initramfs/oldroot\0" - "/run/initramfs/proc\0" - "/run/initramfs/sys\0" - "/run/initramfs/dev\0" - "/run/initramfs/run\0"; + case ARG_LOG_LOCATION: + if (optarg) { + r = log_show_location_from_string(optarg); + if (r < 0) + log_error("Failed to parse log location setting %s, ignoring", optarg); + } else + log_show_location(true); - const char *dir; + break; - if (mount("/run/initramfs", "/run/initramfs", NULL, MS_BIND, NULL) < 0) { - log_error("Failed to mount bind /run/initramfs on /run/initramfs: %m"); - return -errno; - } + case '\001': + if (!arg_verb) + arg_verb = optarg; + else + log_error("Excess arguments, ignoring"); + break; - if (mount(NULL, "/run/initramfs", NULL, MS_PRIVATE, NULL) < 0) { - log_error("Failed to make /run/initramfs private mount: %m"); - return -errno; - } + case '?': + return -EINVAL; - NULSTR_FOREACH(dir, dirs) - if (mkdir_p(dir, 0755) < 0 && errno != EEXIST) { - log_error("Failed to mkdir %s: %m", dir); - return -errno; + default: + assert_not_reached("Unhandled option code."); } - if (mount("/sys", "/run/initramfs/sys", NULL, MS_BIND, NULL) < 0) { - log_error("Failed to mount bind /sys on /run/initramfs/sys: %m"); - return -errno; - } - - if (mount("/proc", "/run/initramfs/proc", NULL, MS_BIND, NULL) < 0) { - log_error("Failed to mount bind /proc on /run/initramfs/proc: %m"); - return -errno; - } - - if (mount("/dev", "/run/initramfs/dev", NULL, MS_BIND, NULL) < 0) { - log_error("Failed to mount bind /dev on /run/initramfs/dev: %m"); - return -errno; - } - - if (mount("/run", "/run/initramfs/run", NULL, MS_BIND, NULL) < 0) { - log_error("Failed to mount bind /run on /run/initramfs/run: %m"); - return -errno; + if (!arg_verb) { + log_error("Verb argument missing."); + return -EINVAL; } return 0; } -static int pivot_to_new_root(void) { - int fd; +static int switch_root_initramfs(void) { + if (mount("/run/initramfs", "/run/initramfs", NULL, MS_BIND, NULL) < 0) + return log_error_errno(errno, "Failed to mount bind /run/initramfs on /run/initramfs: %m"); - chdir("/run/initramfs"); + if (mount(NULL, "/run/initramfs", NULL, MS_PRIVATE, NULL) < 0) + return log_error_errno(errno, "Failed to make /run/initramfs private mount: %m"); - /* - In case some evil process made "/" MS_SHARED - It works for pivot_root, but the ref count for the root device - is not decreasing :-/ - */ - if (mount(NULL, "/", NULL, MS_PRIVATE, NULL) < 0) { - log_error("Failed to make \"/\" private mount %m"); - return -errno; - } - - if (pivot_root(".", "oldroot") < 0) { - log_error("pivot failed: %m"); - /* only chroot if pivot root succeded */ - return -errno; - } - - chroot("."); - log_info("Successfully changed into root pivot."); - - fd = open("/dev/console", O_RDWR); - if (fd < 0) - log_error("Failed to open /dev/console: %m"); - else { - make_stdio(fd); - - /* Initialize the controlling terminal */ - setsid(); - ioctl(STDIN_FILENO, TIOCSCTTY, NULL); - } - - return 0; + /* switch_root with MS_BIND, because there might still be processes lurking around, which have open file descriptors. + * /run/initramfs/shutdown will take care of these. + * Also do not detach the old root, because /run/initramfs/shutdown needs to access it. + */ + return switch_root("/run/initramfs", "/oldroot", false, MS_BIND); } + int main(int argc, char *argv[]) { - int cmd, r; + bool need_umount, need_swapoff, need_loop_detach, need_dm_detach; + bool in_container, use_watchdog = false; + _cleanup_free_ char *cgroup = NULL; + char *arguments[3]; unsigned retries; - bool need_umount = true, need_swapoff = true, need_loop_detach = true, need_dm_detach = true; - bool killed_everbody = false, in_container, use_watchdog = false; + int cmd, r; log_parse_environment(); - log_set_target(LOG_TARGET_CONSOLE); /* syslog will die if not gone yet */ + r = parse_argv(argc, argv); + if (r < 0) + goto error; + + /* journald will die if not gone yet. The log target defaults + * to console, but may have been changed by command line options. */ + + log_close_console(); /* force reopen of /dev/console */ log_open(); umask(0022); if (getpid() != 1) { - log_error("Not executed by init (pid 1)."); + log_error("Not executed by init (PID 1)."); r = -EPERM; goto error; } - if (argc != 2) { - log_error("Invalid number of arguments."); - r = -EINVAL; - goto error; - } - - in_container = detect_container(NULL) > 0; - - if (streq(argv[1], "reboot")) + if (streq(arg_verb, "reboot")) cmd = RB_AUTOBOOT; - else if (streq(argv[1], "poweroff")) + else if (streq(arg_verb, "poweroff")) cmd = RB_POWER_OFF; - else if (streq(argv[1], "halt")) + else if (streq(arg_verb, "halt")) cmd = RB_HALT_SYSTEM; - else if (streq(argv[1], "kexec")) + else if (streq(arg_verb, "kexec")) cmd = LINUX_REBOOT_CMD_KEXEC; else { - log_error("Unknown action '%s'.", argv[1]); r = -EINVAL; + log_error("Unknown action '%s'.", arg_verb); goto error; } + cg_get_root_path(&cgroup); + use_watchdog = !!getenv("WATCHDOG_USEC"); /* lock us into memory */ mlockall(MCL_CURRENT|MCL_FUTURE); log_info("Sending SIGTERM to remaining processes..."); - send_signal(SIGTERM); + broadcast_signal(SIGTERM, true, true); log_info("Sending SIGKILL to remaining processes..."); - send_signal(SIGKILL); + broadcast_signal(SIGKILL, true, false); - if (in_container) { - need_swapoff = false; - need_dm_detach = false; - } + in_container = detect_container(NULL) > 0; + + need_umount = !in_container; + need_swapoff = !in_container; + need_loop_detach = !in_container; + need_dm_detach = !in_container; /* Unmount all mountpoints, swaps, and loopback devices */ for (retries = 0; retries < FINALIZE_ATTEMPTS; retries++) { @@ -367,127 +220,199 @@ int main(int argc, char *argv[]) { if (use_watchdog) watchdog_ping(); + /* Let's trim the cgroup tree on each iteration so + that we leave an empty cgroup tree around, so that + container managers get a nice notify event when we + are down */ + if (cgroup) + cg_trim(SYSTEMD_CGROUP_CONTROLLER, cgroup, false); + if (need_umount) { log_info("Unmounting file systems."); r = umount_all(&changed); - if (r == 0) + if (r == 0) { need_umount = false; - else if (r > 0) + log_info("All filesystems unmounted."); + } else if (r > 0) log_info("Not all file systems unmounted, %d left.", r); else - log_error("Failed to unmount file systems: %s", strerror(-r)); + log_error_errno(r, "Failed to unmount file systems: %m"); } if (need_swapoff) { - log_info("Disabling swaps."); + log_info("Deactivating swaps."); r = swapoff_all(&changed); - if (r == 0) + if (r == 0) { need_swapoff = false; - else if (r > 0) - log_info("Not all swaps are turned off, %d left.", r); + log_info("All swaps deactivated."); + } else if (r > 0) + log_info("Not all swaps deactivated, %d left.", r); else - log_error("Failed to turn off swaps: %s", strerror(-r)); + log_error_errno(r, "Failed to deactivate swaps: %m"); } if (need_loop_detach) { log_info("Detaching loop devices."); r = loopback_detach_all(&changed); - if (r == 0) + if (r == 0) { need_loop_detach = false; - else if (r > 0) + log_info("All loop devices detached."); + } else if (r > 0) log_info("Not all loop devices detached, %d left.", r); else - log_error("Failed to detach loop devices: %s", strerror(-r)); + log_error_errno(r, "Failed to detach loop devices: %m"); } if (need_dm_detach) { log_info("Detaching DM devices."); r = dm_detach_all(&changed); - if (r == 0) + if (r == 0) { need_dm_detach = false; - else if (r > 0) - log_warning("Not all DM devices detached, %d left.", r); + log_info("All DM devices detached."); + } else if (r > 0) + log_info("Not all DM devices detached, %d left.", r); else - log_error("Failed to detach DM devices: %s", strerror(-r)); + log_error_errno(r, "Failed to detach DM devices: %m"); } if (!need_umount && !need_swapoff && !need_loop_detach && !need_dm_detach) { if (retries > 0) log_info("All filesystems, swaps, loop devices, DM devices detached."); /* Yay, done */ - break; + goto initrd_jump; } /* If in this iteration we didn't manage to - * unmount/deactivate anything, we either kill more - * processes, or simply give up */ + * unmount/deactivate anything, we simply give up */ if (!changed) { - - if (killed_everbody) { - /* Hmm, we already killed everybody, - * let's just give up */ - log_error("Cannot finalize remaining file systems and devices, giving up."); - break; - } - - log_warning("Cannot finalize remaining file systems and devices, trying to kill remaining processes."); - ultimate_send_signal(SIGTERM); - ultimate_send_signal(SIGKILL); - killed_everbody = true; + log_info("Cannot finalize remaining%s%s%s%s continuing.", + need_umount ? " file systems," : "", + need_swapoff ? " swap devices," : "", + need_loop_detach ? " loop devices," : "", + need_dm_detach ? " DM devices," : ""); + goto initrd_jump; } - log_debug("Couldn't finalize remaining file systems and devices after %u retries, trying again.", retries+1); + log_debug("After %u retries, couldn't finalize remaining %s%s%s%s trying again.", + retries + 1, + need_umount ? " file systems," : "", + need_swapoff ? " swap devices," : "", + need_loop_detach ? " loop devices," : "", + need_dm_detach ? " DM devices," : ""); } - if (retries >= FINALIZE_ATTEMPTS) - log_error("Too many iterations, giving up."); + log_error("Too many iterations, giving up."); - execute_directory(SYSTEM_SHUTDOWN_PATH, NULL, NULL); + initrd_jump: - /* If we are in a container, just exit, this will kill our - * container for good. */ - if (in_container) { - log_error("Exiting container."); - exit(0); - } + arguments[0] = NULL; + arguments[1] = arg_verb; + arguments[2] = NULL; + execute_directory(SYSTEM_SHUTDOWN_PATH, DEFAULT_TIMEOUT_USEC, arguments); - if (access("/run/initramfs/shutdown", X_OK) == 0) { + if (!in_container && !in_initrd() && + access("/run/initramfs/shutdown", X_OK) == 0) { + r = switch_root_initramfs(); + if (r >= 0) { + argv[0] = (char*) "/shutdown"; + + setsid(); + make_console_stdio(); + + log_info("Successfully changed into root pivot.\n" + "Returning to initrd..."); - if (prepare_new_root() >= 0 && - pivot_to_new_root() >= 0) { execv("/shutdown", argv); - log_error("Failed to execute shutdown binary: %m"); - } + log_error_errno(errno, "Failed to execute shutdown binary: %m"); + } else + log_error_errno(r, "Failed to switch root to \"/run/initramfs\": %m"); + } - sync(); - - if (cmd == LINUX_REBOOT_CMD_KEXEC) { - /* We cheat and exec kexec to avoid doing all its work */ - pid_t pid = fork(); - - if (pid < 0) - log_error("Could not fork: %m. Falling back to normal reboot."); - else if (pid > 0) { - wait_for_terminate_and_warn("kexec", pid); - log_warning("kexec failed. Falling back to normal reboot."); - } else { - /* Child */ - const char *args[3] = { "/sbin/kexec", "-e", NULL }; - execv(args[0], (char * const *) args); - return EXIT_FAILURE; + if (need_umount || need_swapoff || need_loop_detach || need_dm_detach) + log_error("Failed to finalize %s%s%s%s ignoring", + need_umount ? " file systems," : "", + need_swapoff ? " swap devices," : "", + need_loop_detach ? " loop devices," : "", + need_dm_detach ? " DM devices," : ""); + + /* The kernel will automaticall flush ATA disks and suchlike + * on reboot(), but the file systems need to be synce'd + * explicitly in advance. So let's do this here, but not + * needlessly slow down containers. */ + if (!in_container) + sync(); + + switch (cmd) { + + case LINUX_REBOOT_CMD_KEXEC: + + if (!in_container) { + /* We cheat and exec kexec to avoid doing all its work */ + pid_t pid; + + log_info("Rebooting with kexec."); + + pid = fork(); + if (pid < 0) + log_error_errno(errno, "Failed to fork: %m"); + else if (pid == 0) { + + const char * const args[] = { + KEXEC, "-e", NULL + }; + + /* Child */ + + execv(args[0], (char * const *) args); + _exit(EXIT_FAILURE); + } else + wait_for_terminate_and_warn("kexec", pid, true); } cmd = RB_AUTOBOOT; + /* Fall through */ + + case RB_AUTOBOOT: + + if (!in_container) { + _cleanup_free_ char *param = NULL; + + if (read_one_line_file(REBOOT_PARAM_FILE, ¶m) >= 0) { + log_info("Rebooting with argument '%s'.", param); + syscall(SYS_reboot, LINUX_REBOOT_MAGIC1, LINUX_REBOOT_MAGIC2, LINUX_REBOOT_CMD_RESTART2, param); + } + } + + log_info("Rebooting."); + break; + + case RB_POWER_OFF: + log_info("Powering off."); + break; + + case RB_HALT_SYSTEM: + log_info("Halting system."); + break; + + default: + assert_not_reached("Unknown magic"); } reboot(cmd); - log_error("Failed to invoke reboot(): %m"); + if (errno == EPERM && in_container) { + /* If we are in a container, and we lacked + * CAP_SYS_BOOT just exit, this will kill our + * container for good. */ + log_info("Exiting container."); + exit(0); + } + + log_error_errno(errno, "Failed to invoke reboot(): %m"); r = -errno; error: - log_error("Critical error while doing system shutdown: %s", strerror(-r)); + log_emergency_errno(r, "Critical error while doing system shutdown: %m"); freeze(); - return EXIT_FAILURE; }