diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c
index caf04d70ba71..bbd3bff885a1 100644
--- a/net/netlink/genetlink.c
+++ b/net/netlink/genetlink.c
@@ -362,8 +362,10 @@ int genl_register_family(struct genl_family *family)
 
 	family->id = idr_alloc(&genl_fam_idr, family,
 			       start, end + 1, GFP_KERNEL);
-	if (!family->id)
+	if (family->id < 0) {
+		err = family->id;
 		goto errout_locked;
+	}
 
 	err = genl_validate_assign_mc_groups(family);
 	if (err)