diff --git a/reactos/lib/rtl/atom.c b/reactos/lib/rtl/atom.c
index 1720e64666e..b2f43c9a627 100644
--- a/reactos/lib/rtl/atom.c
+++ b/reactos/lib/rtl/atom.c
@@ -610,6 +610,10 @@ RtlQueryAtomInAtomTable(PRTL_ATOM_TABLE AtomTable,
                   *NameLength = Length;
                }
           }
+        else if (NameLength != NULL)
+          {
+             *NameLength = (Entry->NameLength + 1) * sizeof(WCHAR);
+          }
 
         return Status;
      }
@@ -651,6 +655,10 @@ RtlQueryAtomInAtomTable(PRTL_ATOM_TABLE AtomTable,
                   *NameLength = Length;
                }
           }
+        else if (NameLength != NULL)
+          {
+             *NameLength = (Entry->NameLength + 1) * sizeof(WCHAR);
+          }
      }
    else
      {
diff --git a/reactos/subsys/win32k/ntuser/class.c b/reactos/subsys/win32k/ntuser/class.c
index 8082196c97a..915b9662b6f 100644
--- a/reactos/subsys/win32k/ntuser/class.c
+++ b/reactos/subsys/win32k/ntuser/class.c
@@ -208,7 +208,7 @@ IntGetClassName(struct _WINDOW_OBJECT *WindowObject, LPWSTR lpClassName,
    Length = 0;
    Status = RtlQueryAtomInAtomTable(WinStaObject->AtomTable,
                                     WindowObject->Class->Atom, NULL, NULL, NULL, &Length);
-   Name = ExAllocatePoolWithTag(PagedPool, Length + sizeof(UNICODE_NULL), TAG_STRING);
+   Name = ExAllocatePoolWithTag(PagedPool, Length, TAG_STRING);
    Status = RtlQueryAtomInAtomTable(WinStaObject->AtomTable,
                                     WindowObject->Class->Atom, NULL, NULL, Name, &Length);
    if (!NT_SUCCESS(Status))