Is seller liable after sale if he/she did not pull permits

[Kelly Nellig]

I  hired a contractor a while back to remodel a home I recently sold. The homehowner/buyer has contacted me after the now 5 months after the sale, and informed me that there are significant issues with the home and various things not up to code. The contractor I hired to remodel,  installed a new roof, and provided a certificate and 5 year warranty, however, the homeowner sent me pictures that show the roof was not up to code ( i.e., drains installed backwards and not properly sloped, the corners of the roof not nailed down to the trim, foam installed  and painted over along gaps between the trim and roof where it should be sealed etc.) The homeowner/buyer also said there were significant leaks inside the house. I'm nervous because I do not know for sure, whether or not my contractor pulled the permits for the roof, as well as over improvements made to the house so things may or may not be up to code. Does the buyer have any ground to stand on here if I disclosed I did not know about any of these things during the sale? If there is liability for not pulling permits and current damage/things not up to code, would that be on me, my contractor or the buyer since they have signed the disclosure document?