iwlwifi: mvm: fix potential SKB leak on TXQ TX

commit df2378ab0f2a9dd4cf4501268af1902cc4ebacd8 upstream.

When we transmit after TXQ dequeue, we aren't paying attention to
the return value of the transmit functions, leading to a potential
SKB leak.

Refactor the code a bit (and rename ..._tx to ..._tx_sta) to check
for this happening.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Fixes: cfbc6c4c5b91 ("iwlwifi: mvm: support mac80211 TXQs model")
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c b/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
index d31f96c..49aeab7 100644 (file)
--- a/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
@@ -742,6 +742,20 @@ int iwl_mvm_mac_setup_register(struct iwl_mvm *mvm)
        return ret;
 }
 
+static void iwl_mvm_tx_skb(struct iwl_mvm *mvm, struct sk_buff *skb,
+                          struct ieee80211_sta *sta)
+{
+       if (likely(sta)) {
+               if (likely(iwl_mvm_tx_skb_sta(mvm, skb, sta) == 0))
+                       return;
+       } else {
+               if (likely(iwl_mvm_tx_skb_non_sta(mvm, skb) == 0))
+                       return;
+       }
+
+       ieee80211_free_txskb(mvm->hw, skb);
+}
+
 static void iwl_mvm_mac_tx(struct ieee80211_hw *hw,
                           struct ieee80211_tx_control *control,
                           struct sk_buff *skb)
@@ -785,14 +799,7 @@ static void iwl_mvm_mac_tx(struct ieee80211_hw *hw,
                }
        }
 
-       if (sta) {
-               if (iwl_mvm_tx_skb(mvm, skb, sta))
-                       goto drop;
-               return;
-       }
-
-       if (iwl_mvm_tx_skb_non_sta(mvm, skb))
-               goto drop;
+       iwl_mvm_tx_skb(mvm, skb, sta);
        return;
  drop:
        ieee80211_free_txskb(hw, skb);
@@ -842,10 +849,7 @@ void iwl_mvm_mac_itxq_xmit(struct ieee80211_hw *hw, struct ieee80211_txq *txq)
                                break;
                        }
 
-                       if (!txq->sta)
-                               iwl_mvm_tx_skb_non_sta(mvm, skb);
-                       else
-                               iwl_mvm_tx_skb(mvm, skb, txq->sta);
+                       iwl_mvm_tx_skb(mvm, skb, txq->sta);
                }
        } while (atomic_dec_return(&mvmtxq->tx_request));
        rcu_read_unlock();

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/mvm.h b/drivers/net/wireless/intel/iwlwifi/mvm/mvm.h
index 5ca50f3..5f1ecbb 100644 (file)
--- a/drivers/net/wireless/intel/iwlwifi/mvm/mvm.h
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/mvm.h
@@ -1508,8 +1508,8 @@ int __must_check iwl_mvm_send_cmd_status(struct iwl_mvm *mvm,
 int __must_check iwl_mvm_send_cmd_pdu_status(struct iwl_mvm *mvm, u32 id,
                                             u16 len, const void *data,
                                             u32 *status);
-int iwl_mvm_tx_skb(struct iwl_mvm *mvm, struct sk_buff *skb,
-                  struct ieee80211_sta *sta);
+int iwl_mvm_tx_skb_sta(struct iwl_mvm *mvm, struct sk_buff *skb,
+                      struct ieee80211_sta *sta);
 int iwl_mvm_tx_skb_non_sta(struct iwl_mvm *mvm, struct sk_buff *skb);
 void iwl_mvm_set_tx_cmd(struct iwl_mvm *mvm, struct sk_buff *skb,
                        struct iwl_tx_cmd *tx_cmd,

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/tx.c b/drivers/net/wireless/intel/iwlwifi/mvm/tx.c
index cd9f6c5..d9d82f6 100644 (file)
--- a/drivers/net/wireless/intel/iwlwifi/mvm/tx.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/tx.c
@@ -1203,8 +1203,8 @@ drop:
        return -1;
 }
 
-int iwl_mvm_tx_skb(struct iwl_mvm *mvm, struct sk_buff *skb,
-                  struct ieee80211_sta *sta)
+int iwl_mvm_tx_skb_sta(struct iwl_mvm *mvm, struct sk_buff *skb,
+                      struct ieee80211_sta *sta)
 {
        struct iwl_mvm_sta *mvmsta = iwl_mvm_sta_from_mac80211(sta);
        struct ieee80211_tx_info info;