From f5e58f2d4f217e7b62d40ea926401392adb85590 Mon Sep 17 00:00:00 2001
From: MedicOP <MedicOP@users.noreply.github.com>
Date: Mon, 14 Jan 2019 01:20:05 +0100
Subject: [PATCH] Sync login state on channel change (#323)

---
 .../handlers/PlayerLoggedinHandler.java       | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/src/net/server/channel/handlers/PlayerLoggedinHandler.java b/src/net/server/channel/handlers/PlayerLoggedinHandler.java
index f8b3ea62b6..2081c59d6e 100644
--- a/src/net/server/channel/handlers/PlayerLoggedinHandler.java
+++ b/src/net/server/channel/handlers/PlayerLoggedinHandler.java
@@ -122,7 +122,6 @@ public final class PlayerLoggedinHandler extends AbstractMaplePacketHandler {
         c.setPlayer(player);
         c.setAccID(player.getAccountID());
         
-        int state = c.getLoginState();
         boolean allowLogin = true;
         
         World world = server.getWorld(c.getWorld());
@@ -157,13 +156,19 @@ public final class PlayerLoggedinHandler extends AbstractMaplePacketHandler {
             }
         }
         */
-        
-        if (state != MapleClient.LOGIN_SERVER_TRANSITION || !allowLogin) {
-            c.setPlayer(null);
-            c.announce(MaplePacketCreator.getAfterLoginError(7));
-            return;
+
+        c.lockClient(); // Sync this to prevent wrong login state for double channel changes
+        try {
+            int state = c.getLoginState();
+            if (state != MapleClient.LOGIN_SERVER_TRANSITION || !allowLogin) {
+                c.setPlayer(null);
+                c.announce(MaplePacketCreator.getAfterLoginError(7));
+                return;
+            }
+            c.updateLoginState(MapleClient.LOGIN_LOGGEDIN);
+        } finally {
+            c.unlockClient();
         }
-        c.updateLoginState(MapleClient.LOGIN_LOGGEDIN);
         
         cserv.addPlayer(player);
         world.addPlayer(player);