diff --git a/Xext/xres.c b/Xext/xres.c
index 9bd70c6..f444c4e 100644
--- a/Xext/xres.c
+++ b/Xext/xres.c
@@ -64,7 +64,7 @@ ProcXResQueryClients (ClientPtr client)
 
     REQUEST_SIZE_MATCH(xXResQueryClientsReq);
 
-    current_clients = xalloc((currentMaxClients - 1) * sizeof(int));
+    current_clients = xalloc(currentMaxClients * sizeof(int));
 
     num_clients = 0;
     for(i = 0; i < currentMaxClients; i++) {