#include "mkdir.h"
#include "virt.h"
#include "watchdog.h"
+#include "killall.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;
- }
-
- if (k >= 0)
- log_warning("sigtimedwait() returned unexpected signal.");
- }
- }
-}
-
-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);
-}
-
-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");
-
- r = kill(-1, sign);
- if (r < 0 && errno != ESRCH)
- log_warning("kill(-1, %s) failed: %m", signal_to_string(sign));
-
- if (kill(-1, SIGCONT) < 0 && errno != ESRCH)
- log_warning("kill(-1, SIGCONT) failed: %m");
-
- if (r < 0)
- goto finish;
-
- wait_for_children(0, &mask);
-
-finish:
- sigprocmask(SIG_SETMASK, &oldmask, NULL);
-}
-
static int prepare_new_root(void) {
static const char dirs[] =
"/run/initramfs/oldroot\0"
}
static int pivot_to_new_root(void) {
+
if (chdir("/run/initramfs") < 0) {
log_error("Failed to change directory to /run/initramfs: %m");
return -errno;
}
- /*
- 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;
- }
+ /* Work-around for a kernel bug: for some reason the kernel
+ * refuses switching root if any file systems are mounted
+ * MS_SHARED. Hence remount them MS_PRIVATE here as a
+ * work-around.
+ *
+ * https://bugzilla.redhat.com/show_bug.cgi?id=847418 */
+ if (mount(NULL, "/", NULL, MS_REC|MS_PRIVATE, NULL) < 0)
+ log_warning("Failed to make \"/\" private mount: %m");
if (pivot_root(".", "oldroot") < 0) {
log_error("pivot failed: %m");
- /* only chroot if pivot root succeded */
+ /* only chroot if pivot root succeeded */
return -errno;
}
int cmd, r;
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;
+ bool in_container, use_watchdog = false;
char *arguments[3];
log_parse_environment();
mlockall(MCL_CURRENT|MCL_FUTURE);
log_info("Sending SIGTERM to remaining processes...");
- send_signal(SIGTERM);
+ broadcast_signal(SIGTERM, true);
log_info("Sending SIGKILL to remaining processes...");
- send_signal(SIGKILL);
+ broadcast_signal(SIGKILL, true);
if (in_container) {
need_swapoff = false;
need_dm_detach = false;
+ need_loop_detach = false;
}
/* Unmount all mountpoints, swaps, and loopback devices */
}
/* 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_error("Cannot finalize remaining file systems and devices, giving up.");
+ break;
}
log_debug("Couldn't finalize remaining file systems and devices after %u retries, trying again.", retries+1);
arguments[2] = NULL;
execute_directory(SYSTEM_SHUTDOWN_PATH, NULL, arguments);
- /* If we are in a container, just exit, this will kill our
- * container for good. */
- if (in_container) {
- log_error("Exiting container.");
- exit(0);
- }
-
- if (access("/run/initramfs/shutdown", X_OK) == 0) {
+ if (!in_container &&
+ access("/run/initramfs/shutdown", X_OK) == 0) {
if (prepare_new_root() >= 0 &&
pivot_to_new_root() >= 0) {
}
}
- 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 (!in_container) {
+ /* 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;
+ }
}
cmd = RB_AUTOBOOT;
}
reboot(cmd);
+
+ 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_error("Exiting container.");
+ exit(0);
+ }
+
log_error("Failed to invoke reboot(): %m");
r = -errno;
~ianmdlvl / elogind.git / blobdiff