Static route operator periodically crashes with panic: panic called with nil argument #130

The static route operator periodically terminates with:

panic: panic called with nil argument
The failure appears to be related to the route manager goroutine.

Suspected cause
main.go starts the route manager with:

go func() {
panic(routeManager.Run(stopChan))
}()

However, RouteManager.Run() can return nil.

In pkg/routemanager/routemanager.go:

case update, ok := <-updateChan:
if !ok {
return nil
}

case <-stopChan:
return nil

The updateChan is supplied by netlink.RouteSubscribe(). If the netlink subscription terminates, the channel can be closed and Run() consequently returns nil.

The caller then effectively executes:

panic(nil) that leads to ---> panic: panic called with nil argument

Related issue
There is another instance where panic(nil) can be called, but it's less probable issue:

if !crdFound {
params.logger.Info("CRD not found: staticroutes.static-route.ibm.com")
panic(err)
}
At this point err can be nil, because the preceding discovery call has already checked err != nil.

Expected behavior
The operator should never execute panic(nil).

For the route manager, an unexpected termination of the netlink subscription should either:

• return a meaningful error and let the existing process-restart mechanism handle it,
• or preferably reconnect/restart the netlink subscription without terminating the whole operator.

For the missing CRD case, the operator should panic/return a meaningful error such as:

CRD not found: staticroutes.static-route.ibm.com
rather than panic(nil).