X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fcore%2Fshutdown.c;h=48ed7fa1c3a0eb25d2e6d718137815125fdf910a;hb=609c3029076da1ba423673161e5d0fc82ccca6b6;hp=e7771c968e79e848771b18771666233318e2ac39;hpb=418b9be50018303cde79b423d4701b7fd86ddbdc;p=elogind.git diff --git a/src/core/shutdown.c b/src/core/shutdown.c index e7771c968..48ed7fa1c 100644 --- a/src/core/shutdown.c +++ b/src/core/shutdown.c @@ -48,6 +48,7 @@ #include "killall.h" #include "cgroup-util.h" #include "def.h" +#include "switch-root.h" #define FINALIZE_ATTEMPTS 50 @@ -74,9 +75,9 @@ static int parse_argv(int argc, char *argv[]) { assert(argc >= 1); assert(argv); - opterr = 0; - - while ((c = getopt_long(argc, argv, ":", options, NULL)) >= 0) + /* "-" 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) { case ARG_LOG_LEVEL: @@ -114,40 +115,29 @@ static int parse_argv(int argc, char *argv[]) { break; - case '?': - log_error("Unknown option %s.", argv[optind-1]); - return -EINVAL; + case '\001': + if (!arg_verb) + arg_verb = optarg; + else + log_error("Excess arguments, ignoring"); + break; - case ':': - log_error("Missing argument to %s.", argv[optind-1]); + case '?': return -EINVAL; default: assert_not_reached("Unhandled option code."); } - if (optind >= argc) { + if (!arg_verb) { log_error("Verb argument missing."); return -EINVAL; } - arg_verb = argv[optind]; - - if (optind + 1 < argc) - log_error("Excess arguments, ignoring"); return 0; } -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"; - - const char *dir; - +static int switch_root_initramfs(void) { 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; @@ -158,66 +148,13 @@ static int prepare_new_root(void) { return -errno; } - NULSTR_FOREACH(dir, dirs) - if (mkdir_p_label(dir, 0755) < 0 && errno != EEXIST) { - log_error("Failed to mkdir %s: %m", dir); - return -errno; - } - - 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; - } - - return 0; + /* switch_root with MS_BIND, because there might still be processes lurking around, which have open file desriptors. + * /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); } -static int pivot_to_new_root(void) { - - if (chdir("/run/initramfs") < 0) { - log_error("Failed to change directory to /run/initramfs: %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 succeeded */ - return -errno; - } - - chroot("."); - - setsid(); - make_console_stdio(); - - log_info("Successfully changed into root pivot."); - - return 0; -} int main(int argc, char *argv[]) { bool need_umount, need_swapoff, need_loop_detach, need_dm_detach; @@ -233,7 +170,7 @@ int main(int argc, char *argv[]) { goto error; /* journald will die if not gone yet. The log target defaults - * to console, but may have been changed by commandline options. */ + * to console, but may have been changed by command line options. */ log_close_console(); /* force reopen of /dev/console */ log_open(); @@ -275,7 +212,7 @@ int main(int argc, char *argv[]) { in_container = detect_container(NULL) > 0; - need_umount = true; + need_umount = !in_container; need_swapoff = !in_container; need_loop_detach = !in_container; need_dm_detach = !in_container; @@ -375,20 +312,25 @@ int main(int argc, char *argv[]) { arguments[0] = NULL; arguments[1] = arg_verb; arguments[2] = NULL; - execute_directory(SYSTEM_SHUTDOWN_PATH, NULL, DEFAULT_TIMEOUT_USEC, arguments, NULL); + execute_directory(SYSTEM_SHUTDOWN_PATH, NULL, DEFAULT_TIMEOUT_USEC, arguments); if (!in_container && !in_initrd() && access("/run/initramfs/shutdown", X_OK) == 0) { + r = switch_root_initramfs(); + if (r >= 0) { + argv[0] = (char*) "/shutdown"; - if (prepare_new_root() >= 0 && - pivot_to_new_root() >= 0) { - arguments[0] = (char*) "/shutdown"; + setsid(); + make_console_stdio(); - log_info("Returning to initrd..."); + log_info("Successfully changed into root pivot.\n" + "Returning to initrd..."); - execv("/shutdown", arguments); + execv("/shutdown", argv); log_error("Failed to execute shutdown binary: %m"); - } + } else + log_error("Failed to switch root to \"/run/initramfs\": %s", strerror(-r)); + } if (need_umount || need_swapoff || need_loop_detach || need_dm_detach) @@ -442,8 +384,7 @@ int main(int argc, char *argv[]) { 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); + syscall(SYS_reboot, LINUX_REBOOT_MAGIC1, LINUX_REBOOT_MAGIC2, LINUX_REBOOT_CMD_RESTART2, param); } }