Re: [ros-dev] [ros-diffs] [pschweitzer] 65166: [NTFS] Simplify buffer size management in GetNtfsFileRecord(). As tests shown, Windows doesn't care about the real size of the file record and expects the caller to pass the co...

[Thomas Faber]

On 2014-11-01 11:02, [e-mail] wrote:
> OutputBuffer->FileRecordLength = FileRecord->BytesInUse;
> RtlCopyMemory(OutputBuffer->FileRecordBuffer, FileRecord, FileRecord->BytesInUse);
> OutputBuffer->FileRecordLength = DeviceExt->NtfsInfo.BytesPerFileRecord;
> RtlCopyMemory(OutputBuffer->FileRecordBuffer, FileRecord, DeviceExt->NtfsInfo.BytesPerFileRecord);

Wait, now there's no check against OutputBufferLength at all? It should
at least be
min(DeviceExt->NtfsInfo.BytesPerFileRecord,
    Stack->Parameters.FileSystemControl.OutputBufferLength)
in the memcpy size. Or am I missing something?

[Pierre Schweitzer]

You're missing line 611 where we check against size:
Stack->Parameters.FileSystemControl.OutputBufferLength <
(FIELD_OFFSET(NTFS_FILE_RECORD_OUTPUT_BUFFER, FileRecordBuffer) +
DeviceExt->NtfsInfo.BytesPerFileRecord)

On 01/11/2014 11:13, Thomas Faber wrote:
> On 2014-11-01 11:02, [e-mail] wrote:
> > OutputBuffer->FileRecordLength = FileRecord->BytesInUse;
> > RtlCopyMemory(OutputBuffer->FileRecordBuffer, FileRecord, FileRecord->BytesInUse);
> > OutputBuffer->FileRecordLength = DeviceExt->NtfsInfo.BytesPerFileRecord;
> > RtlCopyMemory(OutputBuffer->FileRecordBuffer, FileRecord, DeviceExt->NtfsInfo.BytesPerFileRecord);
>
> Wait, now there's no check against OutputBufferLength at all? It should
> at least be
> min(DeviceExt->NtfsInfo.BytesPerFileRecord,
>     Stack->Parameters.FileSystemControl.OutputBufferLength)
> in the memcpy size. Or am I missing something?
>
> Ros-dev mailing list
> [e-mail]
> http://www.reactos.org/mailman/listinfo/ros-dev
-- 
Pierre Schweitzer <pierre at reactos.org>
System & Network Administrator
Senior Kernel Developer
ReactOS Deutschland e.V.

[Thomas Faber]

Ah, indeed. Looks good, thanks.

On 2014-11-01 11:14, Pierre Schweitzer wrote:
> You're missing line 611 where we check against size:
> Stack->Parameters.FileSystemControl.OutputBufferLength <
> (FIELD_OFFSET(NTFS_FILE_RECORD_OUTPUT_BUFFER, FileRecordBuffer) +
> DeviceExt->NtfsInfo.BytesPerFileRecord)
>
> On 01/11/2014 11:13, Thomas Faber wrote:
> > On 2014-11-01 11:02, [e-mail] wrote:
> > > OutputBuffer->FileRecordLength = FileRecord->BytesInUse;
> > > RtlCopyMemory(OutputBuffer->FileRecordBuffer, FileRecord, FileRecord->BytesInUse);
> > > OutputBuffer->FileRecordLength = DeviceExt->NtfsInfo.BytesPerFileRecord;
> > > RtlCopyMemory(OutputBuffer->FileRecordBuffer, FileRecord, DeviceExt->NtfsInfo.BytesPerFileRecord);
> >
> > Wait, now there's no check against OutputBufferLength at all? It should
> > at least be
> > min(DeviceExt->NtfsInfo.BytesPerFileRecord,
> >     Stack->Parameters.FileSystemControl.OutputBufferLength)
> > in the memcpy size. Or am I missing something?

[Thomas Faber]

On 2014-11-01 11:13, Thomas Faber wrote:
> On 2014-11-01 11:02, [e-mail] wrote:
> > OutputBuffer->FileRecordLength = FileRecord->BytesInUse;
> > RtlCopyMemory(OutputBuffer->FileRecordBuffer, FileRecord, FileRecord->BytesInUse);
> > OutputBuffer->FileRecordLength = DeviceExt->NtfsInfo.BytesPerFileRecord;
> > RtlCopyMemory(OutputBuffer->FileRecordBuffer, FileRecord, DeviceExt->NtfsInfo.BytesPerFileRecord);
>
> Wait, now there's no check against OutputBufferLength at all? It should
> at least be
> min(DeviceExt->NtfsInfo.BytesPerFileRecord,
>     Stack->Parameters.FileSystemControl.OutputBufferLength)
> in the memcpy size. Or am I missing something?

Er... Stack->Parameters.FileSystemControl.OutputBufferLength -
FIELD_OFFSET(...) obviously