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Re: loc2c-runtime deref()
Hi -
roland wrote:
> > Then can you please educate me/us about how come your macros call
> > __get_user_asm, the same routines defined in asm/uaccess.h that are
> > used for get_user(), copy_from_user(), and so on?
>
> __get_user_asm is a handy macro that implements the fetch with fault
> recovery. Read the uaccess.h code to see what it does. [...]
OK. So you are indeed passing kernel-space pointers to this routine,
which in (all?) other cases is given __user pointers. This works
because normally the kernel address space is mapped at constant
addresses, and that this low-level function bypasses the usual
access_ok checks. It is in a way a coincidence.
> I provided macros that work. [...]
OK. (It would not work on 4G+4G, right?)
- FChE