Hands off the intercept if 'unpatch' fails...

base/iat_patch.cc

 // Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/iat_patch.h"
 #include "base/logging.h"
 
 namespace iat_patch {
 
 struct InterceptFunctionInformation {
@@ skipping 190 matching lines @@
     intercept_function_ = new_function;
   }
 
   return error;
 }
 
 DWORD IATPatchFunction::Unpatch() {
   DWORD error = RestoreImportedFunction(intercept_function_,
                                         original_function_,
                                         iat_thunk_);
+  DCHECK(NO_ERROR == error);
 
-  if (NO_ERROR == error) {
-    intercept_function_ = NULL;
-    original_function_ = NULL;
-    iat_thunk_ = NULL;
-  }
+  // Hands off the intercept if we fail to unpatch.
+  // If IATPatchFunction::Unpatch fails during RestoreImportedFunction
+  // it means that we cannot safely unpatch the import address table
+  // patch. In this case its better to be hands off the intercept as
+  // trying to unpatch again in the destructor of IATPatchFunction is
+  // not going to be any safer
+  intercept_function_ = NULL;
+  original_function_ = NULL;
+  iat_thunk_ = NULL;
 
   return error;
 }
 
 }  // namespace iat_patch