Re: [PATCH] Staging: rtl8187se: fix styling issues in r8180_wx.c

[Dan Carpenter <dan.carpenter@oracle.com>]

On Sun, Jan 05, 2014 at 04:17:36PM -0500, Dan LaManna wrote:
> @@ -1358,22 +1358,22 @@ static inline int is_same_network(struct ieee80211_network *src,
>  		 * We treat all <hidden> with the same BSSID and channel
>  		 * as one network
>  		 */
> -		return (((src->ssid_len == dst->ssid_len) || (ieee->iw_mode == IW_MODE_INFRA)) && /* YJ,mod, 080819,for hidden ap */
> +		return ((src->ssid_len == dst->ssid_len) || (ieee->iw_mode == IW_MODE_INFRA)) && /* YJ,mod, 080819,for hidden ap */
>  			(src->channel == dst->channel) &&
>  			!memcmp(src->bssid, dst->bssid, ETH_ALEN) &&
>  			(!memcmp(src->ssid, dst->ssid, src->ssid_len) || (ieee->iw_mode == IW_MODE_INFRA)) &&  /* YJ,mod, 080819,for hidden ap */
>  			((src->capability & WLAN_CAPABILITY_IBSS) ==
>  			(dst->capability & WLAN_CAPABILITY_IBSS)) &&
>  			((src->capability & WLAN_CAPABILITY_BSS) ==
> -			(dst->capability & WLAN_CAPABILITY_BSS)));
> +			(dst->capability & WLAN_CAPABILITY_BSS));
>  }
>  

Break this up.

	if (src->channel != dst->channel)
		return 0;

	if (memcmp(src->bssid, dst->bssid, ETH_ALEN) != 0)
		return 0;

	if (ieee->iw_mode == IW_MODE_INFRA) {
		if (src->ssid_len != dst->ssid_len)
			return 0;
		if (memcmp(src->ssid, dst->ssid, src->ssid_len) != 0)
			return 0;
	}

	if (src->capability & WLAN_CAPABILITY_IBSS !=
	    dst->capability & WLAN_CAPABILITY_IBSS)
		return 0;
	if (src->capability & WLAN_CAPABILITY_BSS !=
	    dst->capability & WLAN_CAPABILITY_BSS)
	    	return 0;

	return 1;

In the original code we don't verify that dst->ssid_len is valid if
ieee->iw_mode == IW_MODE_INFRA.  That means there is a potential Oops
if we read too far in the memcmp(src->ssid, dst->ssid, src->ssid_len).
I haven't reviewed the callers so it may not be a real issue.

regards,
dan carpenter