FILE_STANDARD_INFORMATION::field_16 and field_17?

Hi,

for years, the structure of FILE_STANDARD_INFORMATION is defined like this:

2: kd\> dt _FILE_STANDARD_INFORMATION  
ntdll!_FILE_STANDARD_INFORMATION  
 +0x000 AllocationSize : _LARGE_INTEGER  
 +0x008 EndOfFile : _LARGE_INTEGER  
 +0x010 NumberOfLinks : Uint4B  
 +0x014 DeletePending : UChar  
 +0x015 Directory : UChar  

However, in the wcifs.sys driver (Windows 10 17134 x86), references offsets 16 and 17 of this structure (both 1 byte size, both zeros in my test case). Does anyone know what do these fields contain?

FILE_STANDARD_INFORMATION_EX, from wdm.h:

#if (_WIN32_WINNT >= _WIN32_WINNT_WINTHRESHOLD)
typedef struct _FILE_STANDARD_INFORMATION_EX {
LARGE_INTEGER AllocationSize;
LARGE_INTEGER EndOfFile;
ULONG NumberOfLinks;
BOOLEAN DeletePending;
BOOLEAN Directory;
BOOLEAN AlternateStream;
BOOLEAN MetadataAttribute;
} FILE_STANDARD_INFORMATION_EX, *PFILE_STANDARD_INFORMATION_EX;
#endif

-scott
OSR
@OSRDrivers