This aluminum venting was stretched out about 10 feet into a tiny opening in the roof. You can't really see it because the switch box floating in front of it, but it was tiny! We opened the hole a bit and fixed the roof cap so it would stop leaking.
The original vent was coming into the attic directly under a PVC pipe. We had to adjust the PVC and move the opening so our rigid pipe would clear everything. If you notice the lint everywhere, the vent had burst at some point and the dryer had been exhausting directly into the attic for awhile.