Your oil leak problem seems typical of a leaky petcock & carb issues.  Rebuild or replace the petcock so gas will not flow while  in the off position & the bike is parked for long periods.
A leaky petcock allows gasoline to flood into one or both float bowls.  If the float needle leaks even a bit, it can get into the combustion chamber & past the piston rings, & into the crankcase.  
No doubt this is what happened to your bike as the oil smelled like gasoline & was probably waaay too over filled  unbeknownst to you prior to your ride.  Too much oil which if diluted with a lot of gasoline has too little viscosity & Wil create to much pressure in the crankcase & get out wherever it can...like through gaskets & seals.
Good luck![/i]
			
			
									
									
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Latest Registry Entry
                        1965 Honda CP77 — Ulsan Metro City, Rep. Korea
                        Restored with original parts — Owner: J. Doe