core,systemctl: refuse switching root if we're not in initrd

src/systemctl/systemctl-switch-root.c

@@ -5,6 +5,7 @@
 #include "bus-locator.h"
 #include "chase.h"
 #include "fd-util.h"
+#include "initrd-util.h"
 #include "parse-util.h"
 #include "path-util.h"
 #include "proc-cmdline.h"
@@ -63,6 +64,9 @@ int verb_switch_root(int argc, char *argv[], void *userdata) {
         } else
                 root = "/sysroot";
 
+        if (!in_initrd())
+                return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Not in initrd, refusing switch-root operation.");
+
         if (argc >= 3)
                 init = argv[2];
         else {