Re: [PATCH] rtw_security: fix cast to restricted __le32

[Greg KH <gregkh@linuxfoundation.org>]

On Sun, Jun 13, 2021 at 06:22:29PM +0800, Jhih-Ming Huang wrote:
> This patch fixes the sparse warning of fix cast to restricted __le32.
> 
> Signed-off-by: Jhih-Ming Huang <fbihjmeric@gmail.com>
> ---
>  drivers/staging/rtl8723bs/core/rtw_security.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/staging/rtl8723bs/core/rtw_security.c b/drivers/staging/rtl8723bs/core/rtw_security.c
> index a99f439328f1..2f4da67e31c6 100644
> --- a/drivers/staging/rtl8723bs/core/rtw_security.c
> +++ b/drivers/staging/rtl8723bs/core/rtw_security.c
> @@ -121,7 +121,7 @@ void rtw_wep_decrypt(struct adapter  *padapter, u8 *precvframe)
>  		arc4_crypt(ctx, payload, payload,  length);
>  
>  		/* calculate icv and compare the icv */
> -		*((u32 *)crc) = le32_to_cpu(~crc32_le(~0, payload, length - 4));
> +		*((u32 *)crc) = le32_to_cpu((__force __le32)~crc32_le(~0, payload, length - 4));

When you use __force, that usually implies something is wrong here.

Look at the recent changes that were just submitted for this a week or
so ago in the mailing list archives, and the discussion about them, to
see the issues involved here.

I would need to see a _LOT_ of description in the changelog about why
these changes are actually correct, before I can take them.

thanks,

greg k-h