An antibacterial soap would help you.These areas always teem with microorganisms.Apply candid powder after bath.
Foul smell from the scar is usually due to a fungal infection. Wash your skin daily and then dry thoroughly by pat drying,not rubbing.The damp skin is an ideal site for fungi to multiply.Also wear cotton clothes and change them twice a day and do not share other people’s towels.Most cases of fungal infections respond to over-the-counter products, which contain any of several basic ingredients: miconazole, tolnaftate, terbinafine,ketaconazole and clotrimazole.You can use clotrimazole powder also.
If the symptoms persist or the rash itches then it will be best to get it evaluated from a dermatologist.
I hope that helps.Take care and pls do keep me posted on how you are doing or if you have any additional doubts.Kind regards.