re: mwifiex: add dump data debug support

re: mwifiex: add dump data debug support

[Dan Carpenter]

Hello Zhaoyang Liu,

This is a semi-automatic email about new static checker warnings.

The patch 868093a9df75: "mwifiex: add dump data debug support" from 
May 12, 2015, leads to the following Smatch complaint:

drivers/net/wireless/mwifiex/cmdevt.c:475 mwifiex_process_event()
	 error: we previously assumed 'skb' could be null (see line 467)

drivers/net/wireless/mwifiex/cmdevt.c
   466	
   467		if (skb) {
                    ^^^
Old check for NULL.

   468			rx_info = MWIFIEX_SKB_RXCB(skb);
   469			memset(rx_info, 0, sizeof(*rx_info));
   470			rx_info->bss_num = priv->bss_num;
   471			rx_info->bss_type = priv->bss_type;
   472		}
   473	
   474		mwifiex_dbg(adapter, EVENT, "EVENT: cause: %#x\n", eventcause);
   475		mwifiex_dbg_dump(adapter, EVT_D, "Event Buf:", skb->data, skb->len);
                                                               ^^^^^
Patch introduces unchecked dereference.

   476	
   477		if (priv->bss_role == MWIFIEX_BSS_ROLE_UAP)

regards,
dan carpenter