iwlwifi: mvm: Protect mvm->csa_vif with RCU

[deliverable/linux.git] / drivers / net / wireless / iwlwifi / mvm / mac-ctxt.c

diff --git a/drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c b/drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c
index 6d094721a20ec62dc0219336cd5917ca173447c3..19bd696bd6f87d75140057c9fd6aa2a53193e96c 100644 (file)
--- a/drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c
+++ b/drivers/net/wireless/iwlwifi/mvm/mac-ctxt.c
@@ -1206,6 +1206,7 @@ int iwl_mvm_rx_beacon_notif(struct iwl_mvm *mvm,
 {
        struct iwl_rx_packet *pkt = rxb_addr(rxb);
        struct iwl_mvm_tx_resp *beacon_notify_hdr;
+       struct ieee80211_vif *csa_vif;
        u64 tsf;
 
        lockdep_assert_held(&mvm->mutex);
@@ -1231,13 +1232,15 @@ int iwl_mvm_rx_beacon_notif(struct iwl_mvm *mvm,
                     mvm->ap_last_beacon_gp2,
                     le32_to_cpu(beacon_notify_hdr->initial_rate));
 
-       if (unlikely(mvm->csa_vif && mvm->csa_vif->csa_active)) {
-               if (!ieee80211_csa_is_complete(mvm->csa_vif)) {
-                       ieee80211_csa_update_counter(mvm->csa_vif);
-                       iwl_mvm_mac_ctxt_beacon_changed(mvm, mvm->csa_vif);
+       csa_vif = rcu_dereference_protected(mvm->csa_vif,
+                                           lockdep_is_held(&mvm->mutex));
+       if (unlikely(csa_vif && csa_vif->csa_active)) {
+               if (!ieee80211_csa_is_complete(csa_vif)) {
+                       ieee80211_csa_update_counter(csa_vif);
+                       iwl_mvm_mac_ctxt_beacon_changed(mvm, csa_vif);
                } else {
-                       ieee80211_csa_finish(mvm->csa_vif);
-                       mvm->csa_vif = NULL;
+                       ieee80211_csa_finish(csa_vif);
+                       RCU_INIT_POINTER(mvm->csa_vif, NULL);
                }
        }