Re: [PATCH 7/10] staging: r8188eu: Add files for new drive: Coccispatch "noderef"

[Dan Carpenter]

On Thu, Sep 19, 2013 at 11:45:46PM +0200, Thomas Meyer wrote:
> sizeof when applied to a pointer typed expression gives the size of the
> pointer.
> Found by coccinelle spatch "misc/noderef.cocci"
> 

When you're writing the changelog for these it helps if you say how
many bytes sizeof(*data) is.  In this case, we have gone from clearing 8
bytes to clearing 1 byte so the original code had a potential memory
corruption bug.

> Signed-off-by: Thomas Meyer <thomas@xxxxxxxx>
> ---
> 
> diff -u -p a/drivers/staging/rtl8188eu/core/rtw_mp.c b/drivers/staging/rtl8188eu/core/rtw_mp.c
> --- a/drivers/staging/rtl8188eu/core/rtw_mp.c
> +++ b/drivers/staging/rtl8188eu/core/rtw_mp.c
> @@ -907,7 +907,7 @@ u32 mp_query_psd(struct adapter *pAdapte
>  		sscanf(data, "pts =%d, start =%d, stop =%d", &psd_pts, &psd_start, &psd_stop);
>  	}
>  
> -	_rtw_memset(data, '\0', sizeof(data));
> +	_rtw_memset(data, '\0', sizeof(*data));

I think your fix is correct but it would be better to remove the memset
and do:

	data[0] = '\0';

"data" is a u8 pointer, but it should obviously be a char pointer.  The
original code here is not high quality.  :P

regards,
dan carpenter

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