[cifs-protocol] SMB1 Trans2SetPathInfo() FileEndOfFileInformation is not enforcing share modes
tim.prouty at isilon.com
Wed Nov 25 11:21:23 MST 2009
Thank you for the quick answer! I have a few comments/questions below.
On Nov 25, 2009, at 9:14 AM, Bill Wesse wrote:
> Hello Tim. I think the difference in the response between the
> standard versus pass-through level lies in how the file handle is
> obtained during the call (given that TRANS2_SET_PATH_INFORMATION
> passes the path, and not the handle). The logical conclusion from
> the trace is that pass-through gets the existing handle, and the non
> pass-through value simply fails, because a new handle cannot be
> opened due to the lack of sharing.
Which existing handle would the pass-through be using? The handle
opened in packet #28 is a separate tcp connection and a separte
session from the Trans2SetPathInfo in packet #33. I'm not aware of
any situation where the server is expected to share file handles
across multiple sessions. Is this an exception?
> I will continue my investigation into the details on the differences
> between the base & pass-through handling, with respect to the file
> path / handle source. Pass-through is basically implementation
> dependent, as noted in [MS-FSCC] (reference below), so there is a
> possibility this may not be further elaborated on in the documents.
If a client can send a particular info level and windows implements
it, then we have a compatibility problem if we choose not to support
it. What I would really like to know is if other SMB implementations
need to circumvent share-mode checks for this pass through level (and
> Of course, TRANS2_SET_FILE_INFORMATION should succeed (without a
> pass-through value), since that requires the file handle (per [MS-
> CIFS] 220.127.116.11 TRANS2_SET_FILE_INFORMATION (0x0008) at http://msdn.microsoft.com/en-us/library/ee442064.aspx)
I agree. A Trans2SetFileInfo on the fid opened in packet #28 from the
same session would have succeeded.
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