Narrated Busrah daughter of Safwan:

Abdullah ibn AbuBakr reported that he heard Urwah say: I entered upon Marwan ibn al-Hakam. We mentioned things that render the ablution void. Marwan said: Does it become void by touching the penis? Urwah replied: This I do not know. Marwan said: Busrah daughter of Safwan reported to me that she heard the Messenger of Allah ﷺ say: He who touches his penis should perform ablution.

حَدَّثَنَا عَبْدُ اللَّهِ بْنُ مَسْلَمَةَ، عَنْ مَالِكٍ، عَنْ عَبْدِ اللَّهِ بْنِ أَبِي بَكْرٍ، أَنَّهُ سَمِعَ عُرْوَةَ، يَقُولُ دَخَلْتُ عَلَى مَرْوَانَ بْنِ الْحَكَمِ فَذَكَرْنَا مَا يَكُونُ مِنْهُ الْوُضُوءُ . فَقَالَ مَرْوَانُ وَمِنْ مَسِّ الذَّكَرِ . فَقَالَ عُرْوَةُ مَا عَلِمْتُ ذَلِكَ . فَقَالَ مَرْوَانُ أَخْبَرَتْنِي بُسْرَةُ بِنْتُ صَفْوَانَ أَنَّهَا سَمِعَتْ رَسُولَ اللَّهِ ﷺ يَقُولُ " مَنْ مَسَّ ذَكَرَهُ فَلْيَتَوَضَّأْ " .