The expiration date of your passport is irrelevant in this case. USCIS has made a mistake as your EAD should be issued either a) through the validity of your I-94 or b) for 2 years, whichever is less.
You can contact USCIS customer service yourself or retain an attorney for assistance.
While this answer is provided by a Florida Bar Certified Expert in Immigration and Nationality Law, it is for general information purposes only and an attorney/client relationship is neither intended nor created. You should seek out qualified counsel to review your case and provide you with advice specific to your situation. Call +1-561-478-5353 to schedule a consultation with Mr. Devore.
When does your passport expire? Otherwise, you can contact customer service.
The above is intended only as general information, and does not constitute legal advice. You must speak with an attorney to discuss your individual case.
Please check your passport's expiration date.
This answer is of a general nature and should not be relied upon as final, nor is it intended as legal advice. Consult with a qualified attorney before making any legal decisions. Gen Kimura, (832) 247-6932.
Have you obtained an extension of the L1 and L2 through 2015? If you obtained an extension to 2015, and have not left the US since your first entry, then the EAD should have been isssued for at leats a year and not to the date of the expiration of your visa. If you traveled out of the US and reenterd with your original vias, that may be why the EAD was issued only until Dec 2012. You should meet with an attorney who specializes in immigration matters and show them all of your docuemtns. They will be able to tell you what is going on and how it can be corrected.