Located behind the rear freezer panel in the freezer compartment are the evaporator coils which will develop ice and frost. The ice and frost must be defrosted every 8-10 hours of operation.
The refrigerator has a defrost timer that will cause the compressor and fans to shut off and turn on the defrost heater to melt the ice. The heater is located directly beneath the evaporator coils. The melted ice and frost will drip down onto an evaporator drain trough/pan located directly under the defrost heating element. The drain trough directs the water towards the center of the trough where there is a drain hole. When the drain hole becomes restricted and stopped up the water can not pass through the hole and down to the drain pan under the refrigerator. The water finds a path of least resistance down through the floor of the freezer or vents and will drip and collect onto the top shelf of the fresh food section.
You will need to remove the ice maker, the air tower, and the evaporator panel to gain access to the drain tough. You may even want to pull the floor of the freezer out also if needed. It appears to have a couple of screws securing it down. It should slide out after removing the 2 screws.
To eliminate the water dripping onto the shelf the drain hole in the center of the drain trough will need to be cleared of the blockage. You can use a hair dryer to aide in defrosting the ice blockage in the drain trough. The pour some hot water to confirm drainage all the way down the defrost drain pan under the refrigerator.