Potentially dangerous so you need to be a bit careful. On the plus side, gas stoves are very controllable and reliable in the main, compared with meths and petrol alternatives.
Good ventilation is essential to avoid CO2 build up, the side effect of which is that you get drowsy and careless – at least have a window half-open and a door adjar. In particular, if you are lying down it’s a risk as CO2 tends to sink to the floor. CO is also a concern so make sure the flame is perfect blue as CO comes from incomplete combustion.
Handling gas should always be done very carefully as a small leak at the seal where the stove/lantern joins to the canister can result in a build-up and ignition and in a van you will be killed by the explosion.
And finally, it should be made very difficult to knock over because you will be surrounded by flammables and you will be lucky to escape if fire breaks out.
I’ve safely used gas stoves safely in tent porches, and gas lanterns inside larger tents for many years, but it’s something to be done with great care and attention.