Fix a FORWARD_NULL defect in ExtractModuleName reported by Coverity....

sandbox/src/sandbox_nt_util.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 "sandbox/src/sandbox_nt_util.h"
 
 #include "sandbox/src/pe_image.h"
 #include "sandbox/src/sandbox_factory.h"
 #include "sandbox/src/target_services.h"
 
@@ skipping 283 matching lines @@
         out_name = AnsiToUnicode(name);
       }
 
       PIMAGE_NT_HEADERS headers = pe.GetNTHeaders();
       if (headers) {
         if (headers->OptionalHeader.AddressOfEntryPoint)
           *flags |= MODULE_HAS_ENTRY_POINT;
         if (headers->OptionalHeader.SizeOfCode)
           *flags |= MODULE_HAS_CODE;
       }
-
     } while (false);
   } __except(EXCEPTION_EXECUTE_HANDLER) {
   }
 
   return out_name;
 }
 
 UNICODE_STRING* GetBackingFilePath(PVOID address) {
   // We'll start with something close to max_path charactes for the name.
   ULONG buffer_bytes = MAX_PATH * 2;
@@ skipping 27 matching lines @@
 }
 
 UNICODE_STRING* ExtractModuleName(const UNICODE_STRING* module_path) {
   if ((!module_path) || (!module_path->Buffer))
     return NULL;
 
   wchar_t* sep = NULL;
   int start_pos = module_path->Length / sizeof(wchar_t) - 1;
   int ix = start_pos;
 
-  for(; ix >= 0; --ix) {
+  for (; ix >= 0; --ix) {
     if (module_path->Buffer[ix] == L'\\') {
       sep = &module_path->Buffer[ix];
       break;
     }
   }
 
   // Ends with path separator. Not a valid module name.
   if ((ix == start_pos) && sep)
     return NULL;
 
   // No path separator found. Use the entire name.
-  if ((ix == 0) && !sep) {
+  if (!sep) {
     sep = &module_path->Buffer[-1];
   }
 
   // Add one to the size so we can null terminate the string.
   size_t size_bytes = (start_pos - ix + 1) * sizeof(wchar_t);
   char* str_buffer = new(NT_ALLOC) char[size_bytes + sizeof(UNICODE_STRING)];
   if (!str_buffer)
     return NULL;
 
   UNICODE_STRING* out_string = reinterpret_cast<UNICODE_STRING*>(str_buffer);
@@ skipping 120 matching lines @@
   UNREFERENCED_PARAMETER(type);
   return buffer;
 }
 
 void __cdecl operator delete(void* memory, void* buffer,
                              sandbox::AllocationType type) {
   UNREFERENCED_PARAMETER(memory);
   UNREFERENCED_PARAMETER(buffer);
   UNREFERENCED_PARAMETER(type);
 }