If "systemctl switch-root" is called with a specific "INIT" or
/proc/cmdline contains "init=", then systemd would not serialize
itsself.
Let systemctl check, if the new init is in the standard systemd
installation path and if so, clear the INIT parameter,
to let systemd serialize itsself.
+#define strappenda3(a, b, c) \
+ ({ \
+ const char *_a_ = (a), *_b_ = (b), *_c_ = (c); \
+ char *_d_; \
+ size_t _x_, _y_, _z_; \
+ _x_ = strlen(_a_); \
+ _y_ = strlen(_b_); \
+ _z_ = strlen(_c_); \
+ _d_ = alloca(_x_ + _y_ + _z_ + 1); \
+ strcpy(stpcpy(stpcpy(_d_, _a_), _b_), _c_); \
+ _d_; \
+ })
+
#define procfs_file_alloca(pid, field) \
({ \
pid_t _pid_ = (pid); \
#define procfs_file_alloca(pid, field) \
({ \
pid_t _pid_ = (pid); \
static int switch_root(sd_bus *bus, char **args) {
_cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
static int switch_root(sd_bus *bus, char **args) {
_cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
- _cleanup_free_ char *init = NULL;
- const char *root;
+ _cleanup_free_ char *cmdline_init = NULL;
+ const char *root, *init;
root = args[1];
if (l >= 3)
root = args[1];
if (l >= 3)
- init = strdup(args[2]);
- parse_env_file("/proc/cmdline", WHITESPACE,
- "init", &init,
- NULL);
+ r = parse_env_file("/proc/cmdline", WHITESPACE,
+ "init", &cmdline_init,
+ NULL);
+ if (r < 0)
+ log_debug("Failed to parse /proc/cmdline: %s", strerror(-r));
- if (!init)
- init = strdup("");
- if (!init)
- return log_oom();
+ if (isempty(init))
+ init = NULL;
+
+ if (init) {
+ const char *root_systemd_path = NULL, *root_init_path = NULL;
+
+ root_systemd_path = strappenda(root, "/" SYSTEMD_BINARY_PATH);
+ root_init_path = strappenda3(root, "/", init);
+
+ /* If the passed init is actually the same as the
+ * systemd binary, then let's suppress it. */
+ if (files_same(root_init_path, root_systemd_path) > 0)
+ init = NULL;
+ }
- log_debug("switching root - root: %s; init: %s", root, init);
+ log_debug("Switching root - root: %s; init: %s", root, strna(init));
r = sd_bus_call_method(
bus,
r = sd_bus_call_method(
bus,