fix(conninfo): Ensure receive_maximum do not exceed limit

include/emqx_mqtt.hrl

@@ -182,6 +182,8 @@
 -define(MAX_PACKET_SIZE, 16#FFFFFFF).
 -define(MAX_TOPIC_AlIAS, 16#FFFF).
 
+-define(MAX_INFLIGHT_HARD_LIMIT, 32767).
+
 %%--------------------------------------------------------------------
 %% MQTT Frame Mask
 %%--------------------------------------------------------------------

priv/emqx.schema

@@ -936,8 +936,8 @@ end}.
 %% 0 is equivalent to maximum allowed
 {mapping, "zone.$name.max_inflight", "emqx.zones", [
   {default, 0},
-  {datatype, integer}
-  {validators, ["range:1-32767"]},
+  {datatype, integer},
+  {validators, ["range:1-32767"]}
 ]}.
 
 %% @doc Retry interval for redelivering QoS1/2 messages.

src/emqx_channel.erl

@@ -1142,9 +1142,13 @@ expiry_interval(Zone, #mqtt_packet_connect{clean_start = false}) ->
 expiry_interval(_Zone, #mqtt_packet_connect{clean_start = true}) ->
     0.
 
--compile({inline, [receive_maximum/2]}).
 receive_maximum(Zone, ConnProps) ->
-    emqx_mqtt_props:get('Receive-Maximum', ConnProps, emqx_zone:max_inflight(Zone)).
+    MaxInflightConfig = case emqx_zone:max_inflight(Zone) of
+                            0 -> ?MAX_INFLIGHT_HARD_LIMIT;
+                            N -> N
+                        end,
+    MaxByClient = emqx_mqtt_props:get('Receive-Maximum', ConnProps, MaxInflightConfig),
+    erlang:min(MaxByClient, MaxInflightConfig).
 
 %%--------------------------------------------------------------------
 %% Run Connect Hooks

src/emqx_session.erl

@@ -662,7 +662,7 @@ inc_expired_cnt(message, N) ->
 
 -compile({inline, [next_pkt_id/1]}).
 
-next_pkt_id(Session = #session{next_pkt_id = 16#FFFF}) ->
+next_pkt_id(Session = #session{next_pkt_id = ?MAX_PACKET_ID}) ->
     Session#session{next_pkt_id = 1};
 
 next_pkt_id(Session = #session{next_pkt_id = Id}) ->