Commit 45854360 authored by Johannes Berg's avatar Johannes Berg Committed by Emmanuel Grumbach

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: 9513c5e1 ("iwlwifi: mvm: Avoid dereferencing sta if it was already flushed")
Reported-by: default avatarLaura Abbott <labbott@redhat.com>
Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
Signed-off-by: default avatarEmmanuel Grumbach <emmanuel.grumbach@intel.com>
parent 628a2918
...@@ -1222,8 +1222,8 @@ static u8 iwl_mvm_get_key_sta_id(struct iwl_mvm *mvm, ...@@ -1222,8 +1222,8 @@ static u8 iwl_mvm_get_key_sta_id(struct iwl_mvm *mvm,
mvmvif->ap_sta_id != IWL_MVM_STATION_COUNT) { mvmvif->ap_sta_id != IWL_MVM_STATION_COUNT) {
u8 sta_id = mvmvif->ap_sta_id; u8 sta_id = mvmvif->ap_sta_id;
sta = rcu_dereference_protected(mvm->fw_id_to_mac_id[sta_id], sta = rcu_dereference_check(mvm->fw_id_to_mac_id[sta_id],
lockdep_is_held(&mvm->mutex)); lockdep_is_held(&mvm->mutex));
/* /*
* It is possible that the 'sta' parameter is NULL, * It is possible that the 'sta' parameter is NULL,
* for example when a GTK is removed - the sta_id will then * 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, ...@@ -1590,14 +1590,15 @@ void iwl_mvm_update_tkip_key(struct iwl_mvm *mvm,
u16 *phase1key) u16 *phase1key)
{ {
struct iwl_mvm_sta *mvm_sta; 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); bool mcast = !(keyconf->flags & IEEE80211_KEY_FLAG_PAIRWISE);
if (WARN_ON_ONCE(sta_id == IWL_MVM_STATION_COUNT))
return;
rcu_read_lock(); 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) { if (!sta) {
sta = rcu_dereference(mvm->fw_id_to_mac_id[sta_id]); sta = rcu_dereference(mvm->fw_id_to_mac_id[sta_id]);
if (WARN_ON(IS_ERR_OR_NULL(sta))) { if (WARN_ON(IS_ERR_OR_NULL(sta))) {
...@@ -1609,6 +1610,8 @@ void iwl_mvm_update_tkip_key(struct iwl_mvm *mvm, ...@@ -1609,6 +1610,8 @@ void iwl_mvm_update_tkip_key(struct iwl_mvm *mvm,
mvm_sta = iwl_mvm_sta_from_mac80211(sta); mvm_sta = iwl_mvm_sta_from_mac80211(sta);
iwl_mvm_send_sta_key(mvm, mvm_sta, keyconf, mcast, iwl_mvm_send_sta_key(mvm, mvm_sta, keyconf, mcast,
iv32, phase1key, CMD_ASYNC, keyconf->hw_key_idx); iv32, phase1key, CMD_ASYNC, keyconf->hw_key_idx);
unlock:
rcu_read_unlock(); rcu_read_unlock();
} }
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment