cache-factory: fix nil pointer runtime panic

For now, when we're using cache factory to launch kata containers,
we would encounter nil pointer runtime panic.

Fixes: #2272

Signed-off-by: Penny Zheng <penny.zheng@arm.com>

cli/factory.go

@@ -88,7 +88,7 @@ func (s *cacheServer) Quit(ctx context.Context, empty *types.Empty) (*types.Empt
 		time.Sleep(time.Second)
 		s.quit()
 	}()
-	return nil, nil
+	return &types.Empty{}, nil
 }
 
 func (s *cacheServer) Status(ctx context.Context, empty *types.Empty) (*pb.GrpcStatus, error) {

virtcontainers/agent.go

@@ -222,7 +222,7 @@ type agent interface {
 	configure(h hypervisor, id, sharePath string, builtin bool, config interface{}) error
 
 	// configureFromGrpc will update agent settings based on provided arguments which from Grpc
-	configureFromGrpc(id string, builtin bool, config interface{}) error
+	configureFromGrpc(h hypervisor, id string, builtin bool, config interface{}) error
 
 	// getVMPath will return the agent vm socket's directory path
 	getVMPath(id string) string

virtcontainers/kata_agent.go

@@ -416,8 +416,8 @@ func (k *kataAgent) configure(h hypervisor, id, sharePath string, builtin bool,
 	return h.addDevice(sharedVolume, fsDev)
 }
 
-func (k *kataAgent) configureFromGrpc(id string, builtin bool, config interface{}) error {
-	return k.internalConfigure(nil, id, "", builtin, config)
+func (k *kataAgent) configureFromGrpc(h hypervisor, id string, builtin bool, config interface{}) error {
+	return k.internalConfigure(h, id, "", builtin, config)
 }
 
 func (k *kataAgent) createSandbox(sandbox *Sandbox) error {

virtcontainers/noop_agent.go

@@ -181,7 +181,7 @@ func (n *noopAgent) configure(h hypervisor, id, sharePath string, builtin bool,
 	return nil
 }
 
-func (n *noopAgent) configureFromGrpc(id string, builtin bool, config interface{}) error {
+func (n *noopAgent) configureFromGrpc(h hypervisor, id string, builtin bool, config interface{}) error {
 	return nil
 }
 

virtcontainers/vm.go

@@ -264,7 +264,7 @@ func NewVMFromGrpc(ctx context.Context, v *pb.GrpcVM, config VMConfig) (*VM, err
 	}
 
 	agent := newAgent(config.AgentType)
-	agent.configureFromGrpc(v.Id, isProxyBuiltIn(config.ProxyType), config.AgentConfig)
+	agent.configureFromGrpc(hypervisor, v.Id, isProxyBuiltIn(config.ProxyType), config.AgentConfig)
 
 	proxy, err := newProxy(config.ProxyType)
 	if err != nil {