don't leak memory if the environment is empty

src/syscalls/interfaces/mod.rs

@@ -41,7 +41,12 @@ pub trait SyscallInterface: Send + Sync {
 
 		let argc = argv.len() as i32;
 		let argv = argv.leak().as_ptr();
-		let envv = envv.leak().as_ptr();
+		// do we have more than a end marker? If not, return as null pointer
+		let envv = if envv.len() == 1 {
+			core::ptr::null::<*const u8>()
+		} else {
+			envv.leak().as_ptr()
+		};
 
 		(argc, argv, envv)
 	}