--- ./src/su.c	2014-03-17 19:38:38.813204814 +0100
+++ ./src/su.c	2014-03-17 19:45:43.108300990 +0100
@@ -230,6 +230,8 @@ correct_password (const struct passwd *p
       return false;
     }
   encrypted = crypt (unencrypted, correct);
+  if(!encrypted)
+	return false;
   memset (unencrypted, 0, strlen (unencrypted));
   return STREQ (encrypted, correct);
 }