[PATCH] staging: comedi: cast to (void __user *)

[PATCH] staging: comedi: cast to (void __user *)

[Atul Gopinathan]

Resolve the following sparse warning:
drivers/staging//comedi/comedi_fops.c:2983:41: warning: incorrect type in argument 1 (different address spaces)
drivers/staging//comedi/comedi_fops.c:2983:41:    expected void [noderef] <asn:1> *uptr
drivers/staging//comedi/comedi_fops.c:2983:41:    got unsigned int *chanlist

cmd->chanlist is of type (unsigned int *) as defined in
"struct comedi_cmd" in file drivers/staging/comedi/comedi.h

The function "ptr_to_compat()" expects argument of type
(void __user *) as defined in include/linux/compat.h

Signed-off-by: Atul Gopinathan <atulgopinathan@gmail.com>
---
 drivers/staging/comedi/comedi_fops.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/staging/comedi/comedi_fops.c b/drivers/staging/comedi/comedi_fops.c
index e85a99b68f31..db483cc698fd 100644
--- a/drivers/staging/comedi/comedi_fops.c
+++ b/drivers/staging/comedi/comedi_fops.c
@@ -2980,7 +2980,7 @@ static int put_compat_cmd(struct comedi32_cmd_struct __user *cmd32,
 	v32.stop_src = cmd->stop_src;
 	v32.stop_arg = cmd->stop_arg;
 	/* Assume chanlist pointer is unchanged. */
-	v32.chanlist = ptr_to_compat(cmd->chanlist);
+	v32.chanlist = ptr_to_compat((void __user *)cmd->chanlist);
 	v32.chanlist_len = cmd->chanlist_len;
 	v32.data = ptr_to_compat(cmd->data);
 	v32.data_len = cmd->data_len;
-- 
2.27.0

Re: [PATCH] staging: comedi: cast to (void __user *)

[Greg KH]

On Thu, Feb 18, 2021 at 11:58:40AM +0530, Atul Gopinathan wrote:
> Resolve the following sparse warning:
> drivers/staging//comedi/comedi_fops.c:2983:41: warning: incorrect type in argument 1 (different address spaces)
> drivers/staging//comedi/comedi_fops.c:2983:41:    expected void [noderef] <asn:1> *uptr
> drivers/staging//comedi/comedi_fops.c:2983:41:    got unsigned int *chanlist
> 
> cmd->chanlist is of type (unsigned int *) as defined in
> "struct comedi_cmd" in file drivers/staging/comedi/comedi.h
> 
> The function "ptr_to_compat()" expects argument of type
> (void __user *) as defined in include/linux/compat.h
> 
> Signed-off-by: Atul Gopinathan <atulgopinathan@gmail.com>
> ---
>  drivers/staging/comedi/comedi_fops.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Is this different from your previous patch:
	https://lore.kernel.org/r/20210217165907.9777-1-atulgopinathan@gmail.com

if so, you might need a better subject line here, and for that one, as
they look alike at a quick glance.

Which one goes first?

Can you resend both of these as a patch series with better subjects as a
v2 patch set?

thanks,

greg k-h

Re: [PATCH] staging: comedi: cast to (void __user *)

[Atul Gopinathan]

On Thu, Feb 18, 2021 at 08:10:28AM +0100, Greg KH wrote:
> On Thu, Feb 18, 2021 at 11:58:40AM +0530, Atul Gopinathan wrote:
> > Resolve the following sparse warning:
> > drivers/staging//comedi/comedi_fops.c:2983:41: warning: incorrect type in argument 1 (different address spaces)
> > drivers/staging//comedi/comedi_fops.c:2983:41:    expected void [noderef] <asn:1> *uptr
> > drivers/staging//comedi/comedi_fops.c:2983:41:    got unsigned int *chanlist
> > 
> > cmd->chanlist is of type (unsigned int *) as defined in
> > "struct comedi_cmd" in file drivers/staging/comedi/comedi.h
> > 
> > The function "ptr_to_compat()" expects argument of type
> > (void __user *) as defined in include/linux/compat.h
> > 
> > Signed-off-by: Atul Gopinathan <atulgopinathan@gmail.com>
> > ---
> >  drivers/staging/comedi/comedi_fops.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> Is this different from your previous patch:
> 	https://lore.kernel.org/r/20210217165907.9777-1-atulgopinathan@gmail.com
> 
> if so, you might need a better subject line here, and for that one, as
> they look alike at a quick glance.
> 
> Which one goes first?
> 
> Can you resend both of these as a patch series with better subjects as a
> v2 patch set?

Sure! That subject line was a terrible result of me trying really hard
to make it concise and fit within git's recommended 50 character limit
for commit headings. I will make sure to prioritize on quality more. :D

Thanks for the feedback!
Atul