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FilterGetMessage receives MessageId null

Sergey_PisarevSergey_Pisarev Member - All Emails Posts: 252
Hello !
In my driver I send notification to user mode:

timeout.QuadPart = -100000000; //10 seconds

stat = send_message_to_um(&rr, sizeof(rr), &timeout);

NTSTATUS send_message_to_um(void* send_buffer, ULONG send_buffer_length, PLARGE_INTEGER timeout)


ULONG reply_buffer_length(0);

return FltSendMessage(get_driver()->get_filter(),








In user mode FilterGetMessage returns success but MessageId is null:
res = FilterGetMessage(port,


sizeof(um_rr.hdr) + sizeof(um_rr.ren_rep),


My custom data in message are ok, only common header is zeroed.

Any ideas what can be the problem ?


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