monitor_iface = UNKNOWN_ADDRESS;
len_rthdr = ieee80211_get_radiotap_len(skb->data);
- hdr = (struct ieee80211_hdr *)skb->data + len_rthdr;
+ hdr = (struct ieee80211_hdr *)(skb->data + len_rthdr);
hdrlen = ieee80211_hdrlen(hdr->frame_control);
/* check the header is complete in the frame */