mac80211: fix a potential NULL access in ieee80211_crypto_hw_decrypt

The NULL pointer access could happen when ieee80211_crypto_hw_decrypt
is called from ieee80211_rx_h_decrypt with the following condition:
1. rx->key->conf.cipher is not WEP, CCMP, TKIP or AES_CMAC
2. rx->sta is NULL

When ieee80211_crypto_hw_decrypt is called, it verifies
rx->sta->cipher_scheme and it will cause Oops if rx->sta is NULL.

This path adds an addirional rx->sta == NULL verification in
ieee80211_crypto_hw_decrypt for this case.

Signed-off-by: Max Stepanov <Max.Stepanov@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Max Stepanov 2014-07-09 16:55:32 +03:00 committed by Johannes Berg
parent fa96aabb6a
commit aeb136c5b4

View File

@ -811,7 +811,7 @@ ieee80211_crypto_hw_encrypt(struct ieee80211_tx_data *tx)
ieee80211_rx_result
ieee80211_crypto_hw_decrypt(struct ieee80211_rx_data *rx)
{
if (rx->sta->cipher_scheme)
if (rx->sta && rx->sta->cipher_scheme)
return ieee80211_crypto_cs_decrypt(rx);
return RX_DROP_UNUSABLE;