mac80211: add debug file for mic failure

The mic failure count provides the number of mic failures that
have happened on a given key (without a countermeasure being
started, since that would remove the key).

Signed-off-by: Saravana <saravanad@posedge.com>
[fix NULL pointer issues]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/net/mac80211/wpa.c b/net/mac80211/wpa.c
index 8bd2f5c6a56e..c175ee866ff4 100644
--- a/net/mac80211/wpa.c
+++ b/net/mac80211/wpa.c
@@ -104,7 +104,7 @@ ieee80211_rx_h_michael_mic_verify(struct ieee80211_rx_data *rx)
          */
         if (status->flag & (RX_FLAG_MMIC_STRIPPED | RX_FLAG_IV_STRIPPED)) {
                 if (status->flag & RX_FLAG_MMIC_ERROR)
-                        goto mic_fail;
+                        goto mic_fail_no_key;
 
                 if (!(status->flag & RX_FLAG_IV_STRIPPED) && rx->key &&
                     rx->key->conf.cipher == WLAN_CIPHER_SUITE_TKIP)
@@ -161,6 +161,9 @@ update_iv:
         return RX_CONTINUE;
 
 mic_fail:
+        rx->key->u.tkip.mic_failures++;
+
+mic_fail_no_key:
         /*
          * In some cases the key can be unset - e.g. a multicast packet, in
          * a driver that supports HW encryption. Send up the key idx only if