On Fri, Apr 23, 2021 at 08:56:19PM +0530, Ashish Kalra wrote:
> On Thu, Apr 22, 2021 at 10:43:13AM +0200, Greg Kroah-Hartman wrote:
> > On Tue, Apr 20, 2021 at 02:31:42PM +0530, Ashish Kalra wrote:
> > > Upon running sparse, "warning: incorrect type in argument 1 (different address spaces)
> > > is brought to notice for this file.let's add correct typecast to make it cleaner and
> > > silence the Sparse warning.
> > >
> > > Signed-off-by: Ashish Kalra <eashishkalra@xxxxxxxxx>
> > > ---
> > > drivers/staging/wlan-ng/p80211netdev.c | 2 +-
> > > 1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/staging/wlan-ng/p80211netdev.c b/drivers/staging/wlan-ng/p80211netdev.c
> > > index 6f9666dc0277..70570e8a5ad2 100644
> > > --- a/drivers/staging/wlan-ng/p80211netdev.c
> > > +++ b/drivers/staging/wlan-ng/p80211netdev.c
> > > @@ -569,7 +569,7 @@ static int p80211knetdev_do_ioctl(struct net_device *dev,
> > > goto bail;
> > > }
> > >
> > > - msgbuf = memdup_user(req->data, req->len);
> > > + msgbuf = memdup_user((void __user *)req->data, req->len);
> >
> > Why isn't data being declared as a __user pointer to start with? Why is
> > the cast needed here?
> >
> > This feels wrong as if it is papering over the real problem.
> >
> > thanks,
> >
> > greg k-h
> Thanks for your inputs
> variable data in structure p80211ioctl_req is used only inside this function and is
> already casted to void __user * for copy_to_user. Should it be changed
> to void __user from caadr_t inside p80211ioctl.h. it should be same at runtime
>
> --- a/drivers/staging/wlan-ng/p80211ioctl.h
> +++ b/drivers/staging/wlan-ng/p80211ioctl.h
> @@ -81,7 +81,7 @@
>
> struct p80211ioctl_req {
> char name[WLAN_DEVNAMELEN_MAX];
> - caddr_t data;
> + void __user *data;
>
> Does this looks ok to you and is there any other check possible if this is ok?
THat looks better. What does running sparse on that change show?
thanks,
greg k-h
