MmExtendSection

NTSTATUS __stdcall MmExtendSection(VOID *SectionToExtend, UINT64 *NewSectionSize, UINT64 IgnoreFileSizeChecking){
  int v3; 
  _CONTROL_AREA *v6; 
  _CONTROL_AREA *v7; 
  _SEGMENT *Segment; 
  UINT64 v9; 
  UINT64 v10; 
  int v11; 
  _SUBSECTION *LastSubsection; 
  unsigned __int64 v13; 
  unsigned __int64 v14; 
  NTSTATUS updated; 
  UINT64 v16; 
  _FILE_OBJECT *v18; 
  _FILE_OBJECT *v19; 
  _LARGE_INTEGER *v20; 
  NTSTATUS v21; 
  _ETHREAD *CurrentThread; 
  _LARGE_INTEGER *ExtendInfo; 
  int v24; 
  UINT64 v25; 
  NTSTATUS v26; 
  __int128 v27[2]; 
  __int64 v28; 
  _LARGE_INTEGER FileSize; 
  UINT64 GrantedAccess; 

  FileSize.QuadPart = 0i64;
  v3 = IgnoreFileSizeChecking;
  memset(v27, 0, sizeof(v27));
  v28 = 0i64;
  v6 = MiSectionControlArea((_SECTION *)SectionToExtend);
  v7 = v6;
  if( (v6->u.LongFlags & 0x420) != 0 || !v6->FilePointer.Value )
    return -1073741689;
  if( *NewSectionSize <= 0x3FFFFFFFFFF000i64 )
  {
    Segment = v6->Segment;
    v9 = *NewSectionSize + 4095;
    DWORD2(v27[0]) = 16;
    v10 = v9 >> 12;
    MiLockControlAreaSectionExtend(v6);
    if( (v7->u.LongFlags & 0x8000) == 0 )
    {
      v25 = *((_QWORD *)SectionToExtend + 6);
      if( *NewSectionSize <= v25 )
      {
        *NewSectionSize = v25;
        MiUnlockControlAreaSectionExtend(v7, (_MI_CONTROL_AREA_WAIT_BLOCK *)v27);
        return 0;
      }
    }
    if( v3 )
      goto LABEL_6;
    MiUnlockControlAreaSectionExtend(v7, (_MI_CONTROL_AREA_WAIT_BLOCK *)v27);
    v18 = MiReferenceControlAreaFile(v7);
    DWORD2(v27[0]) = 32;
    v19 = v18;
    MiLockControlAreaSectionExtend(v7);
    v11 = FsRtlGetFileSize(v19, &FileSize);
    if( v11 >= 0 )
    {
      if( *NewSectionSize <= FileSize.QuadPart )
      {
LABEL_18:
        if( Segment->ExtendInfo )
        {
          CurrentThread = (_ETHREAD *)KeGetCurrentThread();
          --CurrentThread->Tcb.SpecialApcDisable;
          ExAcquirePushLockExclusiveEx(&stru_140C4C6D0, 0i64);
          ExtendInfo = (_LARGE_INTEGER *)Segment->ExtendInfo;
          if( ExtendInfo )
            *ExtendInfo = FileSize;
          if( (_InterlockedExchangeAdd64(&stru_140C4C6D0._bf_0, 0xFFFFFFFFFFFFFFFFui64) & 6) == 2 )
            ExfTryToWakePushLock(&stru_140C4C6D0);
          KeAbPostRelease(&stru_140C4C6D0);
          KiLeaveGuardedRegionUnsafe((__int64)CurrentThread);
        }
        MiUnlockControlAreaSectionExtend(v7, (_MI_CONTROL_AREA_WAIT_BLOCK *)v27);
        MiDereferenceControlAreaFile(v7, v19);
        DWORD2(v27[0]) = 16;
        MiLockControlAreaSectionExtend(v7);
LABEL_6:
        v11 = 0;
        GrantedAccess = 0i64;
        LastSubsection = MiFindLastSubsection(v7, 0i64);
        v13 = Segment->TotalNumberOfPtes | ((unsigned __int64)(Segment->SegmentFlags.Short0 & 0x3FF) << 32);
        if( v10 <= v13 )
        {
          *((_QWORD *)SectionToExtend + 6) = *NewSectionSize;
          if( _InterlockedCompareExchange64((volatile signed __int64 *)&Segment->SizeOfSegment, -1i64, -1i64) < *NewSectionSize )
          {
            _InterlockedExchange64((volatile __int64 *)&Segment->SizeOfSegment, *NewSectionSize);
            MiUpdateLastSubsectionSize(LastSubsection, NewSectionSize, 0i64);
          }
        }
        else
        {
          v14 = v10 - v13;
          if( v14 <= (LastSubsection->_bf_34 & 0x3FFFFFFFu) )
          {
            LOBYTE(v24) = MiControlAreaUsingExtents((INT64)v7);
            if( v24 && LastSubsection->SubsectionBase )
            {
              MiSubsectionNeedsExtents(LastSubsection);
              GrantedAccess = (UINT64)LastSubsection;
            }
            updated = MiUpdateLastSubsectionSize(LastSubsection, NewSectionSize, (unsigned int)v14);
          }
          else
          {
            updated = MiExtendSection(
                        LastSubsection,
                        NewSectionSize,
                        LastSubsection->_bf_34 & 0x3FFFFFFF,
                        v14 - (LastSubsection->_bf_34 & 0x3FFFFFFF));
          }
          v11 = updated;
          if( updated >= 0 )
          {
            v11 = 0;
            _InterlockedExchange64((volatile __int64 *)&Segment->SizeOfSegment, *NewSectionSize);
            *((_QWORD *)SectionToExtend + 6) = *NewSectionSize;
          }
        }
        MiUnlockControlAreaSectionExtend(v7, (_MI_CONTROL_AREA_WAIT_BLOCK *)v27);
        if( GrantedAccess )
        {
          LOBYTE(v26) = MiUpdateActiveSubsection(GrantedAccess, v16);
          return v26;
        }
        return v11;
      }
      if( (*((_DWORD *)SectionToExtend + 15) & 0x44) != 0 )
      {
        FileSize.QuadPart = *NewSectionSize;
        v21 = FsRtlSetFileSize(v19, &FileSize, v20);
        if( v21 >= 0 )
          goto LABEL_18;
        v11 = v21;
      }
      else
      {
        v11 = -1073741689;
      }
    }
    MiUnlockControlAreaSectionExtend(v7, (_MI_CONTROL_AREA_WAIT_BLOCK *)v27);
    MiDereferenceControlAreaFile(v7, v19);
    return v11;
  }
  return -1073741760;
}

Referenced by: