From 735516ed379c162658ab9c000d1febb3de5e22dc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pawe=C5=82=20Chmielowski?= <pawel@process-one.net>
Date: Thu, 4 Apr 2024 11:05:29 +0200
Subject: [PATCH] Don't start sql connection pools for unknown hosts

It's possible to trigger that by passing wrong domain to some ctl commands,
and if you don't have default credentials for sql connections, you get
repeating errors when this pools tries to reconnect from error.
---
 src/ejabberd_sql_sup.erl | 54 ++++++++++++++++++++++------------------
 1 file changed, 30 insertions(+), 24 deletions(-)

diff --git a/src/ejabberd_sql_sup.erl b/src/ejabberd_sql_sup.erl
index ccbc2374c..984f59f62 100644
--- a/src/ejabberd_sql_sup.erl
+++ b/src/ejabberd_sql_sup.erl
@@ -37,30 +37,36 @@ start(Host) ->
     case is_started(Host) of
 	true -> ok;
 	false ->
-	    App = case ejabberd_option:sql_type(Host) of
-		      mysql -> p1_mysql;
-		      pgsql -> p1_pgsql;
-		      sqlite -> sqlite3;
-		      _ -> odbc
-		  end,
-	    ejabberd:start_app(App),
-	    Spec = #{id => gen_mod:get_module_proc(Host, ?MODULE),
-		     start => {ejabberd_sql_sup, start_link, [Host]},
-		     restart => transient,
-		     shutdown => infinity,
-		     type => supervisor,
-		     modules => [?MODULE]},
-	    case supervisor:start_child(ejabberd_db_sup, Spec) of
-		{ok, _} ->
-                    ejabberd_sql_schema:start(Host),
-                    ok;
-		{error, {already_started, Pid}} ->
-                    %% Wait for the supervisor to fully start
-                    _ = supervisor:count_children(Pid),
-                    ok;
-		{error, Why} = Err ->
-		    ?ERROR_MSG("Failed to start ~ts: ~p", [?MODULE, Why]),
-		    Err
+	    case lists:member(Host, ejabberd_option:hosts()) of
+		false ->
+		    ?WARNING_MSG("Rejecting start of sql worker for unknown host: ~ts", [Host]),
+		    {error, invalid_host};
+		true ->
+		    App = case ejabberd_option:sql_type(Host) of
+			      mysql -> p1_mysql;
+			      pgsql -> p1_pgsql;
+			      sqlite -> sqlite3;
+			      _ -> odbc
+			  end,
+		    ejabberd:start_app(App),
+		    Spec = #{id => gen_mod:get_module_proc(Host, ?MODULE),
+			start => {ejabberd_sql_sup, start_link, [Host]},
+			restart => transient,
+			shutdown => infinity,
+			type => supervisor,
+			modules => [?MODULE]},
+		    case supervisor:start_child(ejabberd_db_sup, Spec) of
+			{ok, _} ->
+			    ejabberd_sql_schema:start(Host),
+			    ok;
+			{error, {already_started, Pid}} ->
+			    %% Wait for the supervisor to fully start
+			    _ = supervisor:count_children(Pid),
+			    ok;
+			{error, Why} = Err ->
+			    ?ERROR_MSG("Failed to start ~ts: ~p", [?MODULE, Why]),
+			    Err
+		    end
 	    end
     end.