[PATCH 6/6] d3dx9: Secure against unsafe iface to COM object transitions

[Michael Stefaniuc]

Signed-off-by: Michael Stefaniuc <mstefani at winehq.org>
---
 dlls/d3dx9_36/effect.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/dlls/d3dx9_36/effect.c b/dlls/d3dx9_36/effect.c
index 8152362170..2443c20a63 100644
--- a/dlls/d3dx9_36/effect.c
+++ b/dlls/d3dx9_36/effect.c
@@ -1763,6 +1763,8 @@ static inline struct d3dx_effect_pool *impl_from_ID3DXEffectPool(ID3DXEffectPool
     return CONTAINING_RECORD(iface, struct d3dx_effect_pool, ID3DXEffectPool_iface);
 }
 
+static inline struct d3dx_effect_pool *unsafe_impl_from_ID3DXEffectPool(ID3DXEffectPool *iface);
+
 static inline struct d3dx_effect *impl_from_ID3DXEffect(ID3DXEffect *iface)
 {
     return CONTAINING_RECORD(iface, struct d3dx_effect, ID3DXEffect_iface);
@@ -6162,7 +6164,7 @@ static HRESULT d3dx9_effect_init(struct d3dx_effect *effect, struct IDirect3DDev
     if (pool)
     {
         pool->lpVtbl->AddRef(pool);
-        effect->pool = impl_from_ID3DXEffectPool(pool);
+        effect->pool = unsafe_impl_from_ID3DXEffectPool(pool);
     }
 
     IDirect3DDevice9_AddRef(device);
@@ -6474,6 +6476,14 @@ static const struct ID3DXEffectPoolVtbl ID3DXEffectPool_Vtbl =
     d3dx_effect_pool_Release
 };
 
+static inline struct d3dx_effect_pool *unsafe_impl_from_ID3DXEffectPool(ID3DXEffectPool *iface)
+{
+    if (!iface || iface->lpVtbl != &ID3DXEffectPool_Vtbl)
+        return NULL;
+
+    return impl_from_ID3DXEffectPool(iface);
+}
+
 HRESULT WINAPI D3DXCreateEffectPool(ID3DXEffectPool **pool)
 {
     struct d3dx_effect_pool *object;
-- 
2.20.1