We just got our Schengen visa stamp, but the expiry date is exactly the final day of our trip.
We are leaving Rome on the final day but the problem is that we have a layover at CDG, Paris for several hours and our flight to India is on the next day (the day after our visa expires).

We immediately contacted the Italian embassy that issued the visa (we had provided the flight details too but they seem to have overlooked it) but they insist this is not a problem.

I'm however concerned that exit passport control at CDG will book us for overstay. Anybody who was in a similar situation?

Can you stay at the airport and go through passport control for your flight before the visa runs out, and stay airside until your flight?
Not the most exciting prospect it's true but it would mean you left Schengen on time.

What time does your flight from Rome arrive at CDG and what time does your flight to India depart from CDG?

This exact situation happened to us two years ago and it was not a problem at all. In our case we left Italy in the 90th day and left Frace on the 91st day. The Visa was just fine so don't worry.

jnjfraz,
Did you clear passport control at CDG to exit Schengen before midnight on the 90th day?

The original poster is an Indian national who needs a Schengen visa obtained in advance, and it's for a specific number of days. While US travellers may be overlooked for an overstay of a day or two, it may not be the case for visa nationals.
Their passport will be checked as they leave Schengen prior to boarding their flight to India, and an eagle-eyed border official is likely to spot the visa expiry. I don't think it's serious, and all they get is probably a polite lecture not to do it again. There is no guarantee of course.