Subject: Re: IOCTL implementation and kernel/userland addresses
To: None <tech-kern@NetBSD.org>
From: der Mouse <mouse@Rodents.Montreal.QC.CA>
List: tech-kern
Date: 02/05/2005 12:49:37
> Would proc still be NULL if the IOCTL is called from a kernel thread
> ?
That depends on what the thread passes as the last argument to
VOP_IOCTL, surely?
I know that my diskwatch stuff uses in-kernel ioctls to control part of
the communication between it and the disk drivers, and it passes a nil
proc pointer specifically because it is impossible for userland to
generate such a call and thus any such call can be `trusted'. But if
I'd wanted to I could have passed down curproc (or any other proc
pointer, for that matter) instead.
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