don't know what you mean by "catch" but a runaway process is one that is consuming more resources than you want. So, a runaway looks just like a "non-runaway" process would, the only difference is you want the non-runaway to continue and you want to stop the runaway.

You have tools in the database -- for example, when hosting a development box, I might setup a resource profile that limits CPU per call. Why? Because we code infinite loops "by accident", after a couple hundred thousand iterations the database kills it for me. So, you have "create profile" and "alter user" to assign a profile.

You also have the database resource manager (see the admin guide). It can be used to implement a policy for resource you usage you think "is fair" -- it has things like "no, you cannot even start this query, it will take too long" or "you have generated too much undo, you will be stopped now" or "you only get 20% of the resources on the machine right now" type of policies.