Strengthen bounds check in CWeightTable::Calc.

core/fxge/dib/fx_dib_engine.cpp

Index: core/fxge/dib/fx_dib_engine.cpp
diff --git a/core/fxge/dib/fx_dib_engine.cpp b/core/fxge/dib/fx_dib_engine.cpp
index 88b0d4b271632ce2b7f6aac696e68c34cf6d2ae0..c270661002032def61fc6c1095f98a0494acf2b7 100644
--- a/core/fxge/dib/fx_dib_engine.cpp
+++ b/core/fxge/dib/fx_dib_engine.cpp
@@ -63,6 +63,7 @@ bool CWeightTable::Calc(int dest_len,
 
   m_dwWeightTablesSize = (dest_max - dest_min) * m_ItemSize + 4;
   m_pWeightTables = FX_TryAlloc(uint8_t, m_dwWeightTablesSize);
+  m_dwWeightTablesSize /= sizeof(int);

[Lei Zhang, 2016/09/23 21:32:01]

I think it's weird for a variable to have 2 different units. Maybe add a helper
method to return m_dwWeightTablesSize / sizeof(int), and use that where
appropriate.

   if (!m_pWeightTables)
     return false;