On a liability case, wouldn't it potentially be to the company's advantage to encourage people to set those settings themselves and not to have a default?

I mean, if a company programs the car to do something in a certain situation, then I suspect any resulting court case would be against the company. If the customer sets it up, then presumably people would be more likely to sue the car owner.

I'm not a lawyer, but I suspect no self driving car company would want to make any decision here. Not least because they don't want to be sued into oblivion for it.

Also, a lot of those situations you mention are avoidable for open source. Well, avoidable in that you simply write the laws to specify the buffer space or what not. Then it doesn't matter whether it's an open source user or hacker that's ignored them.