W7 different Lanman server reads/writes from XP?

NTFSD
1

It could be just a coincidence, or it could be something has changed with
some Windows Update… but I found a notable difference in W7’s Lanman
server handling of (local) files read/written over the network.

On XP, in a simple example of saving a Notepad file from a Client PC, there
is a single non-cached WRITE request. Reading the file again does not send
a second non-cached write :wink: Which it obviously should not…
On Windows 7, however, after the first non-cached write, there are MDL
reads, followed by another non-cached Write, on the exact same location.

Am I missing something, or is the cache manager changed to re-issue a Write
after an MdlRead? (strangely, the Write occurs between an MdlRead and
MdlReadComplete)

This is causing an issue for our encryption filter, in that we are given
the non-encrypted data in the second write, since we have re-encrypted the
data during MdlRead.

Or, if anyone managed to get the encryption working on W7 for local files
handlded by Lanman server, what did you do differently from XP
implementation?

Kind regards, Dejan.

2

Noone got the LMSrv encryption working on W7?

Kind regards, Dejan.

On Mon, Sep 1, 2014 at 2:02 PM, Dejan Maksimovic > wrote:

> It could be just a coincidence, or it could be something has changed with
> some Windows Update… but I found a notable difference in W7’s Lanman
> server handling of (local) files read/written over the network.
>
> On XP, in a simple example of saving a Notepad file from a Client PC,
> there is a single non-cached WRITE request. Reading the file again does not
> send a second non-cached write :wink: Which it obviously should not…
> On Windows 7, however, after the first non-cached write, there are MDL
> reads, followed by another non-cached Write, on the exact same location.
>
> Am I missing something, or is the cache manager changed to re-issue a
> Write after an MdlRead? (strangely, the Write occurs between an MdlRead and
> MdlReadComplete)
>
> This is causing an issue for our encryption filter, in that we are given
> the non-encrypted data in the second write, since we have re-encrypted the
> data during MdlRead.
>
> Or, if anyone managed to get the encryption working on W7 for local files
> handlded by Lanman server, what did you do differently from XP
> implementation?
>
> Kind regards, Dejan.
>