wow64: Use ProcessWow64Information to retrieve the 32-bit PEB.

dlls/wow64/syscall.c

@@ -873,7 +873,7 @@ static const WCHAR *get_cpu_dll_name(void)
  */
 static DWORD WINAPI process_init( RTL_RUN_ONCE *once, void *param, void **context )
 {
-    TEB32 *teb32 = (TEB32 *)((char *)NtCurrentTeb() + NtCurrentTeb()->WowTebOffset);
+    PEB32 *peb32;
     HMODULE module, ntdll;
     UNICODE_STRING str = RTL_CONSTANT_STRING( L"ntdll.dll" );
     SYSTEM_BASIC_INFORMATION info;
@@ -884,7 +884,8 @@ static DWORD WINAPI process_init( RTL_RUN_ONCE *once, void *param, void **contex
     NtQuerySystemInformation( SystemEmulationBasicInformation, &info, sizeof(info), NULL );
     highest_user_address = (ULONG_PTR)info.HighestUserAddress;
     default_zero_bits = (ULONG_PTR)info.HighestUserAddress | 0x7fffffff;
-    wow64info = (WOW64INFO *)((PEB32 *)ULongToPtr( teb32->Peb ) + 1);
+    NtQueryInformationProcess( GetCurrentProcess(), ProcessWow64Information, &peb32, sizeof(peb32), NULL );
+    wow64info = (WOW64INFO *)(peb32 + 1);
     wow64info->NativeSystemPageSize = 0x1000;
     wow64info->NativeMachineType    = native_machine;
     wow64info->EmulatedMachineType  = current_machine;