Sayyiduna Abu Hurairah (may Allah be pleased with him) narrates: The Prophet (peace and blessings of Allah be upon him) said salam after performing two rak‘ahs. Sayyiduna Dhul-Yadayn (may Allah be pleased with him) submitted to him: O Messenger of Allah (peace and blessings of Allah be upon him), has the prayer been shortened? The Prophet (peace and blessings of Allah be upon him) asked: Is Dhul-Yadayn speaking the truth? The people replied: Yes. So the Prophet (peace and blessings of Allah be upon him) stood up and performed the remaining two rak‘ahs, then he said salam. Then he said takbeer and performed a prostration like his usual prostrations or a little longer, then he raised his head, then said takbeer and performed a prostration like his usual prostrations or a little longer, then he raised his (head).
Hadith Referenceصحیح ابن حبان / كتاب الصلاة / 2686
Hadith Gradingفضيلة الشيخ الإمام محمد ناصر الدين الألبانيصحيح - «صحيح أبي داود» (924).فضيلة الشيخ العلّامة شُعيب الأرناؤوطإسناده صحيح على شرطهما