X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fshutdown.c;h=528b30b98f0ea6e3d66318f38bf810336fe9d2fd;hp=11c7544fc7c50cd45c42673edd006d25a1f2f4ba;hb=7e2bb92dcae6ee785ff7462aadc8c369fd93715b;hpb=91901329245f070b621a24577393fb8f4ce9bffc diff --git a/src/shutdown.c b/src/shutdown.c index 11c7544fc..528b30b98 100644 --- a/src/shutdown.c +++ b/src/shutdown.c @@ -24,6 +24,11 @@ #include #include #include +#include +#include +#include +#include +#include #include #include #include @@ -32,12 +37,14 @@ #include #include +#include "missing.h" #include "log.h" #include "umount.h" #include "util.h" #define TIMEOUT_USEC (5 * USEC_PER_SEC) #define FINALIZE_ATTEMPTS 50 +#define pivot_root(new_root,put_old) syscall(SYS_pivot_root,new_root,put_old) static bool ignore_proc(pid_t pid) { if (pid == 1) @@ -96,125 +103,191 @@ static int killall(int sign) { return n_processes; } -static int send_signal(int sign) { - sigset_t mask, oldmask; +static void wait_for_children(int n_processes, sigset_t *mask) { usec_t until; - int n_processes; - struct timespec ts; - - assert_se(sigemptyset(&mask) == 0); - assert_se(sigaddset(&mask, SIGCHLD) == 0); - if (sigprocmask(SIG_BLOCK, &mask, &oldmask) != 0) - return -errno; - - if (kill(-1, SIGSTOP) < 0) - log_warning("kill(-1, SIGSTOP) failed: %m"); - - n_processes = killall(sign); - - if (kill(-1, SIGCONT) < 0) - log_warning("kill(-1, SIGCONT) failed: %m"); - if (n_processes <= 0) - goto finish; + assert(mask); until = now(CLOCK_MONOTONIC) + TIMEOUT_USEC; for (;;) { + struct timespec ts; int k; - usec_t n = now(CLOCK_MONOTONIC); + usec_t n; for (;;) { pid_t pid = waitpid(-1, NULL, WNOHANG); if (pid == 0) break; - else if (pid < 0 && errno == ECHILD) { - n_processes = 0; - goto finish; - } - if (--n_processes == 0) - goto finish; + if (pid < 0 && errno == ECHILD) + return; + + if (n_processes > 0) + if (--n_processes == 0) + return; } + n = now(CLOCK_MONOTONIC); if (n >= until) - goto finish; + return; timespec_store(&ts, until - n); - if ((k = sigtimedwait(&mask, NULL, &ts)) != SIGCHLD) { + + if ((k = sigtimedwait(mask, NULL, &ts)) != SIGCHLD) { + + if (k < 0 && errno != EAGAIN) { + log_error("sigtimedwait() failed: %m"); + return; + } + if (k >= 0) log_warning("sigtimedwait() returned unexpected signal."); - if (k < 0 && errno != EAGAIN) - log_warning("sigtimedwait() failed: %m"); } } +} + +static void send_signal(int sign) { + sigset_t mask, oldmask; + int n_processes; + + 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"); + + n_processes = killall(sign); + + if (kill(-1, SIGCONT) < 0 && errno != ESRCH) + log_warning("kill(-1, SIGCONT) failed: %m"); + + if (n_processes <= 0) + goto finish; + + wait_for_children(n_processes, &mask); finish: sigprocmask(SIG_SETMASK, &oldmask, NULL); - - return n_processes; } -static int rescue_send_signal(int sign) { +static void ultimate_send_signal(int sign) { sigset_t mask, oldmask; - usec_t until; - struct timespec ts; int r; - sigemptyset(&mask); - sigaddset(&mask, SIGCHLD); - if (sigprocmask(SIG_BLOCK, &mask, &oldmask) != 0) - return -errno; + assert_se(sigemptyset(&mask) == 0); + assert_se(sigaddset(&mask, SIGCHLD) == 0); + assert_se(sigprocmask(SIG_BLOCK, &mask, &oldmask) == 0); - if (kill(-1, SIGSTOP) < 0) + if (kill(-1, SIGSTOP) < 0 && errno != ESRCH) log_warning("kill(-1, SIGSTOP) failed: %m"); r = kill(-1, sign); - if (r < 0) - log_warning("kill(-1, %d) failed: %m", sign); + if (r < 0 && errno != ESRCH) + log_warning("kill(-1, %s) failed: %m", signal_to_string(sign)); - if (kill(-1, SIGCONT) < 0) + if (kill(-1, SIGCONT) < 0 && errno != ESRCH) log_warning("kill(-1, SIGCONT) failed: %m"); if (r < 0) goto finish; - until = now(CLOCK_MONOTONIC) + TIMEOUT_USEC; - for (;;) { - int k; - usec_t n = now(CLOCK_MONOTONIC); - - for (;;) { - pid_t pid = waitpid(-1, NULL, WNOHANG); - if (pid == 0) - break; - else if (pid < 0 && errno == ECHILD) - goto finish; - } + wait_for_children(0, &mask); - if (n >= until) - goto finish; +finish: + sigprocmask(SIG_SETMASK, &oldmask, NULL); +} - timespec_store(&ts, until - n); - if ((k = sigtimedwait(&mask, NULL, &ts)) != SIGCHLD) { - if (k >= 0) - log_warning("sigtimedwait() returned unexpected signal."); - if (k < 0 && errno != EAGAIN) - log_warning("sigtimedwait() failed: %m"); +static bool prepare_new_root(void) { + int r = false; + const char *dirs[] = { "/run/initramfs/oldroot", + "/run/initramfs/proc", + "/run/initramfs/sys", + "/run/initramfs/dev", + "/run/initramfs/run", + NULL }; + const char **dir; + const char *msg; + + msg = "Failed to mount bind /run/initramfs on /run/initramfs"; + if (mount("/run/initramfs", "/run/initramfs", NULL, MS_BIND, NULL) != 0) + goto out; + + msg="Failed to make /run/initramfs private mount %m:"; + if (mount(NULL, "/run/initramfs", NULL, MS_PRIVATE, NULL) != 0) + goto out; + + for (dir = &dirs[0]; *dir != NULL; dir++) { + asprintf((char **) &msg, "mkdir %s: %%m", *dir); + if (mkdir(*dir, 0755) != 0) { + if (errno != EEXIST) + goto out; } + free((char *) msg); } -finish: - sigprocmask(SIG_SETMASK, &oldmask, NULL); - + msg = "Failed to mount bind /sys on /run/initramfs/sys"; + if (mount("/sys", "/run/initramfs/sys", NULL, MS_BIND, NULL) != 0) + goto out; + msg = "Failed to mount bind /proc on /run/initramfs/proc"; + if (mount("/proc", "/run/initramfs/proc", NULL, MS_BIND, NULL) != 0) + goto out; + msg = "Failed to mount bind /dev on /run/initramfs/dev"; + if (mount("/dev", "/run/initramfs/dev", NULL, MS_BIND, NULL) != 0) + goto out; + msg = "Failed to mount bind /run on /run/initramfs/run"; + if (mount("/run", "/run/initramfs/run", NULL, MS_BIND, NULL) != 0) + goto out; + + r = true; + out: + if (!r) + log_error("%s: %m", msg); return r; } +static bool pivot_to_new_root(void) { + int fd; + int r = 0; + chdir("/run/initramfs"); + + /* + 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 false; + } + + r = pivot_root(".", "oldroot"); + if (r!=0) { + log_error("pivot failed: %m"); + /* only chroot, if pivot root succeded */ + return false; + } + chroot("."); + log_info("pivot rooted"); + + fd = open("dev/console", O_RDONLY); + dup2(fd, STDIN_FILENO); + close_nointr_nofail(fd); + fd = open("dev/console", O_WRONLY); + dup2(fd, STDOUT_FILENO); + close_nointr_nofail(fd); + fd = open("dev/console", O_WRONLY); + dup2(fd, STDERR_FILENO); + close_nointr_nofail(fd); + return true; +} + int main(int argc, char *argv[]) { int cmd, r; unsigned retries; bool need_umount = true, need_swapoff = true, need_loop_detach = true, need_dm_detach = true; - bool killed_everbody = false; + bool killed_everbody = false, in_container; log_parse_environment(); log_set_target(LOG_TARGET_CONSOLE); /* syslog will die if not gone yet */ @@ -232,6 +305,8 @@ int main(int argc, char *argv[]) { goto error; } + in_container = detect_container(NULL) > 0; + if (streq(argv[1], "reboot")) cmd = RB_AUTOBOOT; else if (streq(argv[1], "poweroff")) @@ -251,14 +326,13 @@ int main(int argc, char *argv[]) { log_warning("Cannot lock process memory: %m"); log_info("Sending SIGTERM to remaining processes..."); - r = send_signal(SIGTERM); - if (r < 0) - log_warning("Failed to send SIGTERM to remaining processes: %s", strerror(r)); + send_signal(SIGTERM); log_info("Sending SIGKILL to remaining processes..."); - r = send_signal(SIGKILL); - if (r < 0) - log_warning("Failed to send SIGKILL to remaining processes: %s", strerror(r)); + send_signal(SIGKILL); + + if (in_container) + need_swapoff = false; /* Unmount all mountpoints, swaps, and loopback devices */ for (retries = 0; retries < FINALIZE_ATTEMPTS; retries++) { @@ -325,8 +399,8 @@ int main(int argc, char *argv[]) { } log_warning("Cannot finalize remaining file systems and devices, trying to kill remaining processes."); - rescue_send_signal(SIGTERM); - rescue_send_signal(SIGKILL); + ultimate_send_signal(SIGTERM); + ultimate_send_signal(SIGKILL); killed_everbody = true; } @@ -334,10 +408,30 @@ int main(int argc, char *argv[]) { } if (retries >= FINALIZE_ATTEMPTS) - log_error("Too many interations, giving up."); + log_error("Too many iterations, giving up."); + + execute_directory(SYSTEM_SHUTDOWN_PATH, NULL, NULL); + + /* If we are in a container, just exit, this will kill our + * container for good. */ + if (in_container) { + log_error("Exiting container."); + exit(0); + } sync(); + if (access("/run/initramfs/shutdown", X_OK) == 0) { + char *new_argv[3]; + new_argv[0] = strdup(argv[0]); + new_argv[1] = strdup(argv[1]); + new_argv[2] = NULL; + if (prepare_new_root() && pivot_to_new_root()) { + execv("/shutdown", new_argv); + log_error("Failed to execute shutdown binary: %m"); + } + } + if (cmd == LINUX_REBOOT_CMD_KEXEC) { /* We cheat and exec kexec to avoid doing all its work */ pid_t pid = fork(); @@ -349,7 +443,7 @@ int main(int argc, char *argv[]) { log_warning("kexec failed. Falling back to normal reboot."); } else { /* Child */ - const char *args[5] = { "/sbin/kexec", "-e", "-f", "-x", NULL }; + const char *args[3] = { "/sbin/kexec", "-e", NULL }; execv(args[0], (char * const *) args); return EXIT_FAILURE; } @@ -362,7 +456,6 @@ int main(int argc, char *argv[]) { r = -errno; error: - sync(); log_error("Critical error while doing system shutdown: %s", strerror(-r)); freeze();