2021-02-17 15:45:18

by Pritthijit Nath

Subject: [PATCH] staging: wlan-ng: Fixed incorrect type warning in p80211netdev.c

This change fixes a sparse warning "incorrect type in argument 1
(different address spaces)".

Signed-off-by: Pritthijit Nath <[email protected]>
---
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

2021-02-17 15:57:50

by Greg Kroah-Hartman

Subject: Re: [PATCH] staging: wlan-ng: Fixed incorrect type warning in p80211netdev.c

On Wed, Feb 17, 2021 at 09:12:55PM +0530, Pritthijit Nath wrote:
> This change fixes a sparse warning "incorrect type in argument 1
> (different address spaces)".
>
> Signed-off-by: Pritthijit Nath <[email protected]>
> ---
> 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);

Odd. Why isn't data tagged as a __user pointer to start with?

thanks,

greg k-h

2021-02-17 16:33:34

by Pritthijit Nath

Subject: Re: [PATCH] staging: wlan-ng: Fixed incorrect type warning in p80211netdev.c

On 17/02/21 9:23 pm, Greg KH wrote:
> On Wed, Feb 17, 2021 at 09:12:55PM +0530, Pritthijit Nath wrote:
>> This change fixes a sparse warning "incorrect type in argument 1
>> (different address spaces)".
>>
>> Signed-off-by: Pritthijit Nath <[email protected]>
>> ---
>> 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);
>
> Odd. Why isn't data tagged as a __user pointer to start with?
>
> thanks,
>
> greg k-h
>

In lines 540-548 ->

...

static int p80211knetdev_do_ioctl(struct net_device *dev,
struct ifreq *ifr, int cmd)
{
int result = 0;
struct p80211ioctl_req *req = (struct p80211ioctl_req *)ifr;
struct wlandevice *wlandev = dev->ml_priv;
u8 *msgbuf;

netdev_dbg(dev, "rx'd ioctl, cmd=%d, len=%d\n", cmd, req->len);

...

it can be seen that *req is essentially coming from an explicit cast of *ifr. ifr->data itself is of char* type. So, imo, an explicit __user pointer cast is required.

The patch above was based on the __user pointer cast done in lines 580-586 ->

...

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

...

and lines 550-556 ->

#ifdef SIOCETHTOOL
if (cmd == SIOCETHTOOL) {
result =
p80211netdev_ethtool(wlandev, (void __user *)ifr->ifr_data);
goto bail;
}
#endif

2021-02-18 14:02:11

by Dan Carpenter

Subject: Re: [PATCH] staging: wlan-ng: Fixed incorrect type warning in p80211netdev.c

On Wed, Feb 17, 2021 at 09:12:55PM +0530, Pritthijit Nath wrote:
> This change fixes a sparse warning "incorrect type in argument 1
> (different address spaces)".
>
> Signed-off-by: Pritthijit Nath <[email protected]>
> ---
> 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);

Probably the correct fix is to just change the type of
(struct p80211ioctl_req)->data from caddr_t to "void __user *data;".

I haven't looked at this though, so double check.

regards,
dan carpenter

2021-02-19 07:41:33

by Ivan Safonov

Subject: Re: [PATCH] staging: wlan-ng: Fixed incorrect type warning in p80211netdev.c

On 2/17/21 6:42 PM, pritthijit.nath at icloud.com (Pritthijit Nath) wrote:
> This change fixes a sparse warning "incorrect type in argument 1
> (different address spaces)".
>
> Signed-off-by: Pritthijit Nath <pritthijit.nath at icloud.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;
>

Reviewed-by: Ivan Safonov <[email protected]>