[PATCH] staging: wlan-ng: silence incorrect type in argument 1 (different address spaces) warning

[PATCH] staging: wlan-ng: silence incorrect type in argument 1 (different address spaces) warning

[Ashish Kalra]

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@gmail.com>
---
 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);
 	if (IS_ERR(msgbuf)) {
 		result = PTR_ERR(msgbuf);
 		goto bail;
-- 
2.25.1

Re: [PATCH] staging: wlan-ng: silence incorrect type in argument 1 (different address spaces) warning

[Greg Kroah-Hartman]

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@gmail.com>
> ---
>  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

Re: [PATCH] staging: wlan-ng: silence incorrect type in argument 1 (different address spaces) warning

[Ashish Kalra]

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@gmail.com>
> > ---
> >  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?

Regards
Ashish  

Re: [PATCH] staging: wlan-ng: silence incorrect type in argument 1 (different address spaces) warning

[Greg Kroah-Hartman]

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@gmail.com>
> > > ---
> > >  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

Re: [PATCH] staging: wlan-ng: silence incorrect type in argument 1 (different address spaces) warning

[Greg Kroah-Hartman]

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@gmail.com>
> > > ---
> > >  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?

Wait, what is "caddr_t"?  Try unwinding that mess first...

Re: [PATCH] staging: wlan-ng: silence incorrect type in argument 1 (different address spaces) warning

[Joe Perches]

On Sat, 2021-04-24 at 08:00 +0200, Greg Kroah-Hartman wrote:
> 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.
[]
> >  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?
> 
> Wait, what is "caddr_t"?  Try unwinding that mess first...

Might not be that simple.

include/linux/types.h:typedef __kernel_caddr_t  caddr_t;
include/uapi/linux/coda.h:typedef void * caddr_t;
include/uapi/asm-generic/posix_types.h:typedef char *           __kernel_caddr_t;

Re: [PATCH] staging: wlan-ng: silence incorrect type in argument 1 (different address spaces) warning

[Ashish Kalra]

On Fri, Apr 23, 2021 at 11:11:05PM -0700, Joe Perches wrote:
> On Sat, 2021-04-24 at 08:00 +0200, Greg Kroah-Hartman wrote:
> > 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.
> []
> > >  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?
> > 
> > Wait, what is "caddr_t"?  Try unwinding that mess first...
> 
> Might not be that simple.
> 
> include/linux/types.h:typedef __kernel_caddr_t  caddr_t;
> include/uapi/linux/coda.h:typedef void * caddr_t;
> include/uapi/asm-generic/posix_types.h:typedef char *           __kernel_caddr_t;
> 
> 
data is part of p80211ioctl_req and is used at two places only inside p80211knetdev_do_ioctl
it seems both places it will be used as void __user* only

	msgbuf = memdup_user(req->data, req->len);
        
	if (result == 0) {
                if (copy_to_user
                    ((void __user *)req->data, msgbuf, req->len)) {
                        result = -EFAULT;
                }
        }

Will it still be problem if we change it from char * to void *.?
is there any way to check how caller of this function will be using it?

Re: [PATCH] staging: wlan-ng: silence incorrect type in argument 1 (different address spaces) warning

[Greg Kroah-Hartman]

On Sat, Apr 24, 2021 at 01:45:29PM +0530, Ashish Kalra wrote:
> On Fri, Apr 23, 2021 at 11:11:05PM -0700, Joe Perches wrote:
> > On Sat, 2021-04-24 at 08:00 +0200, Greg Kroah-Hartman wrote:
> > > 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.
> > []
> > > >  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?
> > > 
> > > Wait, what is "caddr_t"?  Try unwinding that mess first...
> > 
> > Might not be that simple.
> > 
> > include/linux/types.h:typedef __kernel_caddr_t  caddr_t;
> > include/uapi/linux/coda.h:typedef void * caddr_t;
> > include/uapi/asm-generic/posix_types.h:typedef char *           __kernel_caddr_t;
> > 
> > 
> data is part of p80211ioctl_req and is used at two places only inside p80211knetdev_do_ioctl
> it seems both places it will be used as void __user* only
> 
> 	msgbuf = memdup_user(req->data, req->len);
>         
> 	if (result == 0) {
>                 if (copy_to_user
>                     ((void __user *)req->data, msgbuf, req->len)) {
>                         result = -EFAULT;
>                 }
>         }
> 
> Will it still be problem if we change it from char * to void *.?

Why do you want to change it to void *?  Never use a void * unless it
has to point to unknown data.  That does not seem the case here.

> is there any way to check how caller of this function will be using it?

Look at the code to determine this...

thanks,

greg k-h

Re: [PATCH] staging: wlan-ng: silence incorrect type in argument 1 (different address spaces) warning

[ashish]

On Sat, Apr 24, 2021 at 10:28:27AM +0200, Greg Kroah-Hartman wrote:
> On Sat, Apr 24, 2021 at 01:45:29PM +0530, Ashish Kalra wrote:
> > On Fri, Apr 23, 2021 at 11:11:05PM -0700, Joe Perches wrote:
> > > On Sat, 2021-04-24 at 08:00 +0200, Greg Kroah-Hartman wrote:
> > > > 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.
> > > []
> > > > >  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?
> > > > 
> > > > Wait, what is "caddr_t"?  Try unwinding that mess first...
> > > 
> > > Might not be that simple.
> > > 
> > > include/linux/types.h:typedef __kernel_caddr_t  caddr_t;
> > > include/uapi/linux/coda.h:typedef void * caddr_t;
> > > include/uapi/asm-generic/posix_types.h:typedef char *           __kernel_caddr_t;
> > > 
> > > 
> > data is part of p80211ioctl_req and is used at two places only inside p80211knetdev_do_ioctl
> > it seems both places it will be used as void __user* only
> > 
> > 	msgbuf = memdup_user(req->data, req->len);
> >         
> > 	if (result == 0) {
> >                 if (copy_to_user
> >                     ((void __user *)req->data, msgbuf, req->len)) {
> >                         result = -EFAULT;
> >                 }
> >         }
> > 
> > Will it still be problem if we change it from char * to void *.?
> 
> Why do you want to change it to void *?  Never use a void * unless it
> has to point to unknown data.  That does not seem the case here.
> 
> > is there any way to check how caller of this function will be using it?
> 
> Look at the code to determine this...
> 
> thanks,
> 
> greg k-h
Thanks Greg and Joe
I have found that adding __user to data is also fixing this warning, 
It should be fine logically to make this change
Please share your opinion and will post v2 for this patch

--- 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;
+       char __user *data;
        u32 magic;
        u16 len;
        u32 result;
-- 
2.30.2

Re: [PATCH] staging: wlan-ng: silence incorrect type in argument 1 (different address spaces) warning

[Greg Kroah-Hartman]

On Tue, Apr 27, 2021 at 05:53:30PM +0530, ashish wrote:
> On Sat, Apr 24, 2021 at 10:28:27AM +0200, Greg Kroah-Hartman wrote:
> > On Sat, Apr 24, 2021 at 01:45:29PM +0530, Ashish Kalra wrote:
> > > On Fri, Apr 23, 2021 at 11:11:05PM -0700, Joe Perches wrote:
> > > > On Sat, 2021-04-24 at 08:00 +0200, Greg Kroah-Hartman wrote:
> > > > > 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.
> > > > []
> > > > > >  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?
> > > > > 
> > > > > Wait, what is "caddr_t"?  Try unwinding that mess first...
> > > > 
> > > > Might not be that simple.
> > > > 
> > > > include/linux/types.h:typedef __kernel_caddr_t  caddr_t;
> > > > include/uapi/linux/coda.h:typedef void * caddr_t;
> > > > include/uapi/asm-generic/posix_types.h:typedef char *           __kernel_caddr_t;
> > > > 
> > > > 
> > > data is part of p80211ioctl_req and is used at two places only inside p80211knetdev_do_ioctl
> > > it seems both places it will be used as void __user* only
> > > 
> > > 	msgbuf = memdup_user(req->data, req->len);
> > >         
> > > 	if (result == 0) {
> > >                 if (copy_to_user
> > >                     ((void __user *)req->data, msgbuf, req->len)) {
> > >                         result = -EFAULT;
> > >                 }
> > >         }
> > > 
> > > Will it still be problem if we change it from char * to void *.?
> > 
> > Why do you want to change it to void *?  Never use a void * unless it
> > has to point to unknown data.  That does not seem the case here.
> > 
> > > is there any way to check how caller of this function will be using it?
> > 
> > Look at the code to determine this...
> > 
> > thanks,
> > 
> > greg k-h
> Thanks Greg and Joe
> I have found that adding __user to data is also fixing this warning, 
> It should be fine logically to make this change
> Please share your opinion and will post v2 for this patch
> 
> --- 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;
> +       char __user *data;
>         u32 magic;
>         u16 len;
>         u32 result;
> -- 
> 2.30.2
> 
> 
> 

What do you think, try it and see and if you think it is correct, please
submit that change.  Don't wait for us...

thanks,

greg k-h