make sure IsMine only returns true when we own all keys

src/script.cpp

@@ -1436,7 +1436,7 @@ bool IsMine(const CKeyStore &keystore, const CScript& scriptPubKey)
         // them) enable spend-out-from-under-you attacks, especially
         // in shared-wallet situations.
         vector<valtype> keys(vSolutions.begin()+1, vSolutions.begin()+vSolutions.size()-1);
-        return HaveKeys(vSolutions, keystore);
+        return HaveKeys(keys, keystore) == keys.size();
     }
     }
     return false;