On Wed, 2019-07-24 at 20:36 +0800, Jia-Ju Bai wrote: > In ieee80211_xmit_fast_finish(), there is an if statement on line 3356 > to check whether key is NULL: > if (key) > > When key is NULL, it is used on line 3388: > switch (key->conf.cipher) > and line 3393: > pn = atomic64_inc_return(&key->conf.tx_pn); > and line 3396: > crypto_hdr[3] = 0x20 | (key->conf.keyidx << 6); > > Thus, possible null-pointer dereferences may occur. No, this cannot happen, because pn_offs can only be non-zero when there is a key. Maybe we should pass the fast_tx pointer instead of the pn_offs/key from it, but the two are coupled. johannes
