Re: null pointer questions

Roman Zippel (zippel@linux-m68k.org)
Sat, 03 Nov 2001 00:20:44 +0100


Hi,

Ken Ashcraft wrote:

> Why does it matter if 0 is a valid user space or not? If I make the call
>
> copy_from_user(0, user_ptr, 4);
>
> the null pointer is the kernel address, not the user address. Can you
> clarify please?

Sorry, I misunderstood you. The kernel address has to be a valid address
of course, otherwise the behavior is undefined.

bye, Roman
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