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I noticed that's where the entry point actually is. For KMDF drivers, it's clear what happens there, if unfortunately too poorly documented to understand much beyond a surface level. For minifilters, all the fltmgr.sys APIs show up in the IAT as direct imports and I don't see any imports not accounted for by user code that might be communicating with kernel components. Is there anything essential being done there? What happens if you set DriverEntry as the entry point?
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Comments
Yes.
Things don't work properly.
I mean... disassemble and walk into the code if you need more than that, right?
Peter Viscarola
OSR
@OSRDrivers
Well I have very, very little knowledge of assembly. I did dump the disassembly and it sure looks like it's not doing anything besides a buffer-overrun protection related __security_init_cookie routine. Can you share your expertise as to why this assessment is incorrect, and why, assuming I could do without buffer overrun protection (old-style WDM drivers obviously run without it), it would not work to skip it, or possibly call it myself?
Does the filter manager enforce the presence of this protection somehow?
Your analysis is correct.
Why on EARTH would you want to do that?
Peter Viscarola
OSR
@OSRDrivers