sd-netlink: don't treat NULL as root type-system

[elogind.git] / src / libsystemd / sd-netlink / netlink-types.c

diff --git a/src/libsystemd/sd-netlink/netlink-types.c b/src/libsystemd/sd-netlink/netlink-types.c
index 4ee0e6148e7c59ab6e9f43c24f0733d3ba54dec8..40548dcbc0ee79c56380b6c1d853925b622e76d8 100644 (file)
--- a/src/libsystemd/sd-netlink/netlink-types.c
+++ b/src/libsystemd/sd-netlink/netlink-types.c
@@ -53,6 +53,15 @@ struct NLTypeSystem {
 
 static const NLTypeSystem rtnl_link_type_system;
 
+static const NLType empty_types[1] = {
+        /* fake array to avoid .types==NULL, which denotes invalid type-systems */
+};
+
+static const NLTypeSystem empty_type_system = {
+        .count = 0,
+        .types = empty_types,
+};
+
 static const NLType rtnl_link_info_data_veth_types[VETH_INFO_MAX + 1] = {
         [VETH_INFO_PEER]  = { .type = NETLINK_TYPE_NESTED, .type_system = &rtnl_link_type_system, .size = sizeof(struct ifinfomsg) },
 };
@@ -450,8 +459,8 @@ static const NLTypeSystem rtnl_neigh_type_system = {
 };
 
 static const NLType rtnl_types[RTM_MAX + 1] = {
-        [NLMSG_DONE]   = { .type = NETLINK_TYPE_META, .size = 0 },
-        [NLMSG_ERROR]  = { .type = NETLINK_TYPE_META, .size = sizeof(struct nlmsgerr) },
+        [NLMSG_DONE]   = { .type = NETLINK_TYPE_NESTED, .type_system = &empty_type_system, .size = 0 },
+        [NLMSG_ERROR]  = { .type = NETLINK_TYPE_NESTED, .type_system = &empty_type_system, .size = sizeof(struct nlmsgerr) },
         [RTM_NEWLINK]  = { .type = NETLINK_TYPE_NESTED, .type_system = &rtnl_link_type_system, .size = sizeof(struct ifinfomsg) },
         [RTM_DELLINK]  = { .type = NETLINK_TYPE_NESTED, .type_system = &rtnl_link_type_system, .size = sizeof(struct ifinfomsg) },
         [RTM_GETLINK]  = { .type = NETLINK_TYPE_NESTED, .type_system = &rtnl_link_type_system, .size = sizeof(struct ifinfomsg) },
@@ -467,7 +476,7 @@ static const NLType rtnl_types[RTM_MAX + 1] = {
         [RTM_GETNEIGH] = { .type = NETLINK_TYPE_NESTED, .type_system = &rtnl_neigh_type_system, .size = sizeof(struct ndmsg) },
 };
 
-const NLTypeSystem rtnl_type_system = {
+const NLTypeSystem type_system_root = {
         .count = ELEMENTSOF(rtnl_types),
         .types = rtnl_types,
 };
@@ -509,10 +518,7 @@ int type_system_get_type(const NLTypeSystem *type_system, const NLType **ret, ui
         const NLType *nl_type;
 
         assert(ret);
-
-        if (!type_system)
-                type_system = &rtnl_type_system;
-
+        assert(type_system);
         assert(type_system->types);
 
         if (type >= type_system->count)
@@ -589,7 +595,7 @@ int type_system_union_protocol_get_type_system(const NLTypeSystemUnion *type_sys
                 return -EOPNOTSUPP;
 
         type_system = &type_system_union->type_systems[protocol];
-        if (type_system->count == 0)
+        if (!type_system->types)
                 return -EOPNOTSUPP;
 
         *ret = type_system;