config: Add hypervisor path override through annotations

The annotation is provided, so it should be respected.
Furthermore, it is important to implement it with the appropriate
protetions similar to what was done for virtiofsd.

Fixes: #3004

Signed-off-by: Christophe de Dinechin <dinechin@redhat.com>

virtcontainers/pkg/oci/utils.go

@@ -399,6 +399,13 @@ func addHypervisorConfigOverrides(ocispec specs.Spec, config *vc.SandboxConfig,
 		return err
 	}
 
+	if value, ok := ocispec.Annotations[vcAnnotations.HypervisorPath]; ok {
+		if !regexpContains(runtime.HypervisorConfig.HypervisorPathList, value) {
+			return fmt.Errorf("hypervisor %v required from annotation is not valid", value)
+		}
+		config.HypervisorConfig.HypervisorPath = value
+	}
+
 	if value, ok := ocispec.Annotations[vcAnnotations.KernelParams]; ok {
 		if value != "" {
 			params := vc.DeserializeParams(strings.Fields(value))