In this call to IEEE80211_NOTE, ni is always NULL due to the assignment a few lines earlier at the start of the function. If debug traces are enabled, then this will pass an invalid pointer as the 'mac' pointer to ieee80211_note_mac. Use IEEE80211_DPRINTF which doesn't take a 'ni' argument instead. Reported by: GCC -Wstringop-overread Reviewed by: bz, emaste Differential Revision: https://reviews.freebsd.org/D37626