diff options
| author | Johannes Berg <johannes.berg@intel.com> | 2015-12-11 09:06:25 +0100 |
|---|---|---|
| committer | Emmanuel Grumbach <emmanuel.grumbach@intel.com> | 2015-12-13 13:38:26 +0200 |
| commit | 4585436091cd812b1165aab71bd4847ea1cb08ec (patch) | |
| tree | cf984f2e986f46770bacdf22dea4fe711f0298fd /drivers | |
| parent | 628a2918afe42fae2f90749ad3721853fd06b262 (diff) | |
| download | linux-stable-4585436091cd812b1165aab71bd4847ea1cb08ec.tar.gz linux-stable-4585436091cd812b1165aab71bd4847ea1cb08ec.tar.bz2 linux-stable-4585436091cd812b1165aab71bd4847ea1cb08ec.zip | |
iwlwifi: mvm: protect RCU dereference in iwl_mvm_get_key_sta_id
Properly protect the RCU dereference in iwl_mvm_get_key_sta_id() when
coming from iwl_mvm_update_tkip_key() which cannot hold the mvm->mutex
by moving the call into the RCU critical section.
Modify the check to use rcu_dereference_check() to permit this.
Fixes: 9513c5e18a0d ("iwlwifi: mvm: Avoid dereferencing sta if it was already flushed")
Reported-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/net/wireless/iwlwifi/mvm/sta.c | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/drivers/net/wireless/iwlwifi/mvm/sta.c b/drivers/net/wireless/iwlwifi/mvm/sta.c index 354acbde088e..2b976b110207 100644 --- a/drivers/net/wireless/iwlwifi/mvm/sta.c +++ b/drivers/net/wireless/iwlwifi/mvm/sta.c @@ -1222,8 +1222,8 @@ static u8 iwl_mvm_get_key_sta_id(struct iwl_mvm *mvm, mvmvif->ap_sta_id != IWL_MVM_STATION_COUNT) { u8 sta_id = mvmvif->ap_sta_id; - sta = rcu_dereference_protected(mvm->fw_id_to_mac_id[sta_id], - lockdep_is_held(&mvm->mutex)); + sta = rcu_dereference_check(mvm->fw_id_to_mac_id[sta_id], + lockdep_is_held(&mvm->mutex)); /* * It is possible that the 'sta' parameter is NULL, * for example when a GTK is removed - the sta_id will then @@ -1590,14 +1590,15 @@ void iwl_mvm_update_tkip_key(struct iwl_mvm *mvm, u16 *phase1key) { struct iwl_mvm_sta *mvm_sta; - u8 sta_id = iwl_mvm_get_key_sta_id(mvm, vif, sta); + u8 sta_id; bool mcast = !(keyconf->flags & IEEE80211_KEY_FLAG_PAIRWISE); - if (WARN_ON_ONCE(sta_id == IWL_MVM_STATION_COUNT)) - return; - rcu_read_lock(); + sta_id = iwl_mvm_get_key_sta_id(mvm, vif, sta); + if (WARN_ON_ONCE(sta_id == IWL_MVM_STATION_COUNT)) + goto unlock; + if (!sta) { sta = rcu_dereference(mvm->fw_id_to_mac_id[sta_id]); if (WARN_ON(IS_ERR_OR_NULL(sta))) { @@ -1609,6 +1610,8 @@ void iwl_mvm_update_tkip_key(struct iwl_mvm *mvm, mvm_sta = iwl_mvm_sta_from_mac80211(sta); iwl_mvm_send_sta_key(mvm, mvm_sta, keyconf, mcast, iv32, phase1key, CMD_ASYNC, keyconf->hw_key_idx); + + unlock: rcu_read_unlock(); } |