On Mon, Mar 10, 2008 at 11:38:49AM -0500, Timur Tabi wrote:
> I'm confused about something in usercopy_64.c:
>
> unsigned long copy_from_user(void *to, const void __user *from, unsigned long
> n)
> {
> if (likely(access_ok(VERIFY_READ, from, n)))
> n = __copy_from_user(to, from, n);
> else
> memset(to, 0, n);
> return n;
> }
>
> If access_ok() returns false, then that means that we cannot copy the data
> from
> user-space. So why are we returning 'n'? Shouldn't we return zero, to let
> the
> caller know that the function failed?
copy_from_user() returns number of bytes _not_ copied.
-Olof
_______________________________________________
Linuxppc-dev mailing list
Linuxppc-dev@ozlabs.org
https://ozlabs.org/mailman/listinfo/linuxppc-dev
