fix: topic matching when deliver retainer msg

apps/emqx_retainer/src/emqx_retainer.app.src

@@ -2,7 +2,7 @@
 {application, emqx_retainer, [
     {description, "EMQX Retainer"},
     % strict semver, bump manually!
-    {vsn, "5.0.26"},
+    {vsn, "5.0.27"},
     {modules, []},
     {registered, [emqx_retainer_sup]},
     {applications, [kernel, stdlib, emqx, emqx_ctl]},

apps/emqx_retainer/src/emqx_retainer_dispatcher.erl

@@ -334,25 +334,62 @@ deliver_in_batches(Msgs, BatchSize, Pid, Topic, Limiter0) ->
             Drop
     end.
 
+-define(DELIVER_ALLOWED, true).
+-define(DELIVER_NOT_ALLOWED, false).
+
 deliver_to_client([Msg | T], Pid, Topic) ->
+    Pipe = emqx_utils:pipeline(
+        [
+            fun check_clientid_banned/2,
+            fun 'check_prefixed_$_with_wildcard'/2
+        ],
+        {Msg, Topic},
+        ?DELIVER_NOT_ALLOWED
+    ),
     _ =
-        case emqx_banned:check_clientid(Msg#message.from) of
-            false ->
+        case Pipe of
+            {ok, _, ?DELIVER_ALLOWED} ->
                 Pid ! {deliver, Topic, Msg};
-            true ->
-                ?tp(
-                    notice,
-                    ignore_retained_message_deliver,
-                    #{
-                        reason => "client is banned",
-                        clientid => Msg#message.from
-                    }
-                )
+            {error, _, _} ->
+                ok
         end,
     deliver_to_client(T, Pid, Topic);
 deliver_to_client([], _, _) ->
     ok.
 
+check_clientid_banned({Msg, _Topic} = Input, _) ->
+    case emqx_banned:check_clientid(Msg#message.from) of
+        false ->
+            {ok, Input, ?DELIVER_ALLOWED};
+        true ->
+            ?tp(
+                notice,
+                ignore_retained_message_deliver,
+                #{
+                    reason => client_is_banned,
+                    clientid => Msg#message.from
+                }
+            ),
+            {error, client_is_banned, ?DELIVER_NOT_ALLOWED}
+    end.
+
+'check_prefixed_$_with_wildcard'({Msg, Topic} = Input, _) ->
+    case emqx_topic:match(Msg#message.topic, Topic) of
+        false ->
+            ?tp(
+                notice,
+                ignore_retained_message_deliver,
+                #{
+                    reason => topic_not_match,
+                    msg_topic => Msg#message.topic,
+                    subscribed_topic => Topic
+                }
+            ),
+            {error, topic_not_match, ?DELIVER_NOT_ALLOWED};
+        true ->
+            {ok, Input, ?DELIVER_ALLOWED}
+    end.
+
 take(N, List) ->
     take(N, List, 0, []).
 

changes/ce/fix-13742.en.md

@@ -0,0 +1 @@
+Fixed when subscribing with `+` as the first level, or `#` as a wildcard, retained messages with topics starting with `$` are incorrectly received.