Exploit dir existing check

Author: Takahiro-Yoko

modules/exploits/linux/local/cve_2023_0386_overlayfs_priv_esc.rb

@@ -117,6 +117,11 @@ def exploit
 
     # Upload exploit executable
     exploit_dir = "#{base_dir}/.#{rand_text_alphanumeric(5..10)}"
+
+    if file_exist?(exploit_dir)
+      fail_with(Failure::BadConfig, 'Exploit dir already exists')
+    end
+
     cmd_exec("mkdir -p #{exploit_dir}")
     if live_compile? && command_exists?('xxd')
       vprint_status('Live compiling exploit on system...')