LM3644: can it block reverse current

Hi team, 

if Vin=0, Vout is high, can LM3644 block Vout to go into VIn? 

from datasheet, the sync MOS is a PMOS, body diode is from SW to Vout, then it should be able to block the voltage from Vout into Vin. Is it right? thanks. 

BRs

Given