diff --git a/kernel/trunk/core/heap.inc b/kernel/trunk/core/heap.inc
index 8f4389ae7e..0407691858 100644
--- a/kernel/trunk/core/heap.inc
+++ b/kernel/trunk/core/heap.inc
@@ -752,6 +752,8 @@ proc user_free stdcall, base:dword
            shl ebx, 8
            mov esi, dword [ebx+PROC_BASE+APPDATA.heap_base]; heap_base
            mov edi, dword [ebx+PROC_BASE+APPDATA.heap_top]; heap_top
+           add esi, new_app_base
+           add edi, new_app_base
            shr esi, 12
            shr edi, 12
 @@: