One appliance and crew from Beaconsfield, one from Slough and one from High Wycombe attended, along with an officer.
One car had left the road and ended up in a ditch.
The firefighters released one man, injured, who was handed into the care of South Central Ambulance Service. They made the scene safe.
Lanes one and two of the motorway were closed while they worked at the scene.
Thames Valley Police and National Highways also attended.