Is there anything I can do about the smell of a diabetic ulcer?

Need antibiotics. Suggests infection and likely by pseudomonas aeruginosa. Requires antibiotics by mouth, inteamuscular or intravenous and treatment by specialists that deal with leg ulcers: vascular surgeons, wound specialists or surgeons, dermatologists dedicated to that, to determine need for debridment and when clean put a graft if needed. Goto your primary doctor he may get cultures, give antibiotic & refer.
Yes. Make sure it is not infected.
Diabetic foot. There are many avenues to seek help: your primary care physician can evaluate you and refer you on; a wound care specialist in a wound center; or a podiatrist that has an interest in wounds are your best choices. But do not hesitate! seek help as soon as possible as foot ulcers in diabetics can get serious very quickly.
Depends. If there is a foul odor it could represent underlying deep infection. You need to see a vascular surgeon right away to address this.
Yes. Odor & diabetic ulcer or wound means infection + / - dead tissue. See a doctor. Antibiotics for infection plus removal of all dead tissue or callus trapping infection. Test if bone is involved. Vascular doppler can be done in the office or at a vascular lab to determine if blood flow to the area is adequate for healing. Stop smoking, remove & prevent pressure, get good control of blood sugars.