validating kernel memory

NTFSD
1

Hello, when filtering NEITHER IO you must probe the UserBuffer before you
use it, typically using the ProbeForXXX routines. This is fine if the
Requestor mode is User but how do you validate the UserBuffer memory if
its Kernel?

Thanks,

Dan.

2

You don’t. You rely on other kernel mode modules that the address is
correct. If the origin is in user space, it has been sent by a kernel mode
module that had (or should have) checked it.

Joze

-----Original Message-----
From: Dan Jones [mailto:xxxxx@hotmail.com]
Sent: Tuesday, July 15, 2003 9:53 AM
To: File Systems Developers
Subject: [ntfsd] validating kernel memory

Hello, when filtering NEITHER IO you must probe the UserBuffer before you
use it, typically using the ProbeForXXX routines. This is fine if the
Requestor mode is User but how do you validate the UserBuffer memory if
its Kernel?

Thanks,

Dan.

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3

No validation at all. Kernel code is trusted.

Max

----- Original Message -----
From: “Dan Jones”
To: “File Systems Developers”
Sent: Tuesday, July 15, 2003 11:52 AM
Subject: [ntfsd] validating kernel memory

> Hello, when filtering NEITHER IO you must probe the UserBuffer
before you
> use it, typically using the ProbeForXXX routines. This is fine if
the
> Requestor mode is User but how do you validate the UserBuffer memory
if
> its Kernel?
>
> Thanks,
>
> Dan.
>
> —
> You are currently subscribed to ntfsd as: xxxxx@storagecraft.com
> To unsubscribe send a blank email to xxxxx@lists.osr.com