[PATCH 2/5] iwlwifi: mvm: take RCU lock before dereferencing

[Luca Coelho]

From: Sara Sharon <sara.sha...@intel.com>

RCU isn't properly locked.

Fixes: 46d372af9935 ("iwlwifi: mvm: rs: new rate scale API - add FW 
notifications")
Signed-off-by: Sara Sharon <sara.sha...@intel.com>
Signed-off-by: Luca Coelho <luciano.coe...@intel.com>
---
 drivers/net/wireless/intel/iwlwifi/mvm/rs-fw.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/rs-fw.c 
b/drivers/net/wireless/intel/iwlwifi/mvm/rs-fw.c
index 55d1274c6092..fb5745660509 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/rs-fw.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/rs-fw.c
@@ -234,13 +234,15 @@ void iwl_mvm_tlc_update_notif(struct iwl_mvm *mvm, struct 
iwl_rx_packet *pkt)
        struct iwl_mvm_sta *mvmsta;
        struct iwl_lq_sta_rs_fw *lq_sta;
 
+       rcu_read_lock();
+
        notif = (void *)pkt->data;
        mvmsta = iwl_mvm_sta_from_staid_rcu(mvm, notif->sta_id);
 
        if (!mvmsta) {
                IWL_ERR(mvm, "Invalid sta id (%d) in FW TLC notification\n",
                        notif->sta_id);
-               return;
+               goto out;
        }
 
        lq_sta = &mvmsta->lq_sta.rs_fw;
@@ -251,6 +253,8 @@ void iwl_mvm_tlc_update_notif(struct iwl_mvm *mvm, struct 
iwl_rx_packet *pkt)
                IWL_DEBUG_RATE(mvm, "new rate_n_flags: 0x%X\n",
                               lq_sta->last_rate_n_flags);
        }
+out:
+       rcu_read_unlock();
 }
 
 void rs_fw_rate_init(struct iwl_mvm *mvm, struct ieee80211_sta *sta,
-- 
2.15.1