MdeModulePkg/VariableSmm: Fix a VariableSmm bug when reading variable with size 0.

Signed-off-by: Tian, Feng <feng.tian@intel.com>
Reviewed-by: Zhang, Chao <chao.b.zhang@intel.com>
git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13725 6f19259b-4bc3-4df7-8a09-765794883524

diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.c b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.c
index 0a6c872baa57788ea60cdf8b6cbe1ac105e678d5..15e55d417ea283f434ccc156cc12f189f570c83a 100644 (file)
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.c
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.c
@@ -426,7 +426,7 @@ SmmVariableHandler (
     return EFI_SUCCESS;\r
   }\r
 \r
-  if (*CommBufferSize < sizeof(SMM_VARIABLE_COMMUNICATE_HEADER) - 1) {\r
+  if (*CommBufferSize < SMM_VARIABLE_COMMUNICATE_HEADER_SIZE) {\r
     return EFI_SUCCESS;\r
   }\r
 \r