Musannaf Ibn Abi Shayba 36:453

Abu Usama narrated to us, from Sulayman ibn al-Mughira, from Thabit, from Anas, who said: Abu Talha came on the day of Hunayn, and the Messenger of Allah (may Allah bless him and grant him peace) was laughing. He said: "O Messenger of Allah, have you not seen Umm Sulaym? She has a dagger with her." The Messenger of Allah (may Allah bless him and grant him peace) said to her: "O Umm Sulaym, what do you intend with it?" She said: "I intend that if one of them approaches me, I will stab him with it."