Re: [linux-next:master 10767/11658] drivers/staging/wlan-ng/p80211netdev.c:572:33: sparse: sparse: incorrect type in argument 1 (different address spaces)

[Ivan Safonov <insafonov@gmail.com>]

On 2/18/21 11:55 AM, kernel test robot wrote:
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
> head:   cd560d8023bf73c94d755908c8d4a0994dd1ec34
> commit: bc4bf94cc2aed9192184782dbb9f884c5d6b9e82 [10767/11658] staging:wlan-ng: use memdup_user instead of kmalloc/copy_from_user
> config: i386-randconfig-s001-20210218 (attached as .config)
> compiler: gcc-9 (Debian 9.3.0-15) 9.3.0
> reproduce:
>          # apt-get install sparse
>          # sparse version: v0.6.3-215-g0fb77bb6-dirty
>          # https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=bc4bf94cc2aed9192184782dbb9f884c5d6b9e82
>          git remote add linux-next https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
>          git fetch --no-tags linux-next master
>          git checkout bc4bf94cc2aed9192184782dbb9f884c5d6b9e82
>          # save the attached .config to linux build tree
>          make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=i386
> 
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@intel.com>
> 

Greg, should I fix my patch?

Pritthijit Nath <pritthijit.nath at icloud.com> has already made a fix 
for this warning:
http://driverdev.linuxdriverproject.org/pipermail/driverdev-devel/2021-February/150785.html

> 
> "sparse warnings: (new ones prefixed by >>)"
>>> drivers/staging/wlan-ng/p80211netdev.c:572:33: sparse: sparse: incorrect type in argument 1 (different address spaces) @@     expected void const [noderef] __user * @@     got char *[usertype] data @@
>     drivers/staging/wlan-ng/p80211netdev.c:572:33: sparse:     expected void const [noderef] __user *
>     drivers/staging/wlan-ng/p80211netdev.c:572:33: sparse:     got char *[usertype] data
> 
> vim +572 drivers/staging/wlan-ng/p80211netdev.c
> 
>     557	
>     558		/* Test the magic, assume ifr is good if it's there */
>     559		if (req->magic != P80211_IOCTL_MAGIC) {
>     560			result = -EINVAL;
>     561			goto bail;
>     562		}
>     563	
>     564		if (cmd == P80211_IFTEST) {
>     565			result = 0;
>     566			goto bail;
>     567		} else if (cmd != P80211_IFREQ) {
>     568			result = -EINVAL;
>     569			goto bail;
>     570		}
>     571	
>   > 572		msgbuf = memdup_user(req->data, req->len);
>     573		if (IS_ERR(msgbuf)) {
>     574			result = PTR_ERR(msgbuf);
>     575			goto bail;
>     576		}
>     577	
>     578		result = p80211req_dorequest(wlandev, msgbuf);
>     579	
>     580		if (result == 0) {
>     581			if (copy_to_user
>     582			    ((void __user *)req->data, msgbuf, req->len)) {
>     583				result = -EFAULT;
>     584			}
>     585		}
>     586		kfree(msgbuf);
>     587	
>     588	bail:
>     589		/* If allocate,copyfrom or copyto fails, return errno */
>     590		return result;
>     591	}
>     592	
> 
> ---
> 0-DAY CI Kernel Test Service, Intel Corporation
> https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
>