mac80211: clean up key freeing a bit

When a key is allocated but not really added, there's no
need to go through the entire teardown process. Also, if
adding a key fails, ieee80211_key_link() can take care of
freeing it instead of the (only) caller.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

3 files changed, 25 insertions, 22 deletions

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 61fc9116380d..c2d4bf24a8c2 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -175,7 +175,7 @@ static int ieee80211_add_key(struct wiphy *wiphy, struct net_device *dev,
                  *       add it to the device after the station.
                  */
                 if (!sta || !test_sta_flag(sta, WLAN_STA_ASSOC)) {
-                        ieee80211_key_free(sdata->local, key);
+                        ieee80211_key_free_unused(key);
                         err = -ENOENT;
                         goto out_unlock;
                 }
@@ -214,8 +214,6 @@ static int ieee80211_add_key(struct wiphy *wiphy, struct net_device *dev,
         }
 
         err = ieee80211_key_link(key, sdata, sta);
-        if (err)
-                ieee80211_key_free(sdata->local, key);
 
  out_unlock:
         mutex_unlock(&sdata->local->sta_mtx);
diff --git a/net/mac80211/key.c b/net/mac80211/key.c
index 99e9f6ae6a54..d86be6466724 100644
--- a/net/mac80211/key.c
+++ b/net/mac80211/key.c
@@ -397,6 +397,15 @@ struct ieee80211_key *ieee80211_key_alloc(u32 cipher, int idx, size_t key_len,
         return key;
 }
 
+static void ieee80211_key_free_common(struct ieee80211_key *key)
+{
+        if (key->conf.cipher == WLAN_CIPHER_SUITE_CCMP)
+                ieee80211_aes_key_free(key->u.ccmp.tfm);
+        if (key->conf.cipher == WLAN_CIPHER_SUITE_AES_CMAC)
+                ieee80211_aes_cmac_key_free(key->u.aes_cmac.tfm);
+        kfree(key);
+}
+
 static void __ieee80211_key_destroy(struct ieee80211_key *key,
                                     bool delay_tailroom)
 {
@@ -412,10 +421,6 @@ static void __ieee80211_key_destroy(struct ieee80211_key *key,
         if (key->local)
                 ieee80211_key_disable_hw_accel(key);
 
-        if (key->conf.cipher == WLAN_CIPHER_SUITE_CCMP)
-                ieee80211_aes_key_free(key->u.ccmp.tfm);
-        if (key->conf.cipher == WLAN_CIPHER_SUITE_AES_CMAC)
-                ieee80211_aes_cmac_key_free(key->u.aes_cmac.tfm);
         if (key->local) {
                 struct ieee80211_sub_if_data *sdata = key->sdata;
 
@@ -431,7 +436,13 @@ static void __ieee80211_key_destroy(struct ieee80211_key *key,
                 }
         }
 
-        kfree(key);
+        ieee80211_key_free_common(key);
+}
+
+void ieee80211_key_free_unused(struct ieee80211_key *key)
+{
+        WARN_ON(key->sdata || key->local);
+        ieee80211_key_free_common(key);
 }
 
 int ieee80211_key_link(struct ieee80211_key *key,
@@ -469,6 +480,9 @@ int ieee80211_key_link(struct ieee80211_key *key,
 
         ret = ieee80211_key_enable_hw_accel(key);
 
+        if (ret)
+                __ieee80211_key_free(key, true);
+
         mutex_unlock(&sdata->local->key_mtx);
 
         return ret;
@@ -489,14 +503,6 @@ void __ieee80211_key_free(struct ieee80211_key *key, bool delay_tailroom)
         __ieee80211_key_destroy(key, delay_tailroom);
 }
 
-void ieee80211_key_free(struct ieee80211_local *local,
-                        struct ieee80211_key *key)
-{
-        mutex_lock(&local->key_mtx);
-        __ieee80211_key_free(key, true);
-        mutex_unlock(&local->key_mtx);
-}
-
 void ieee80211_enable_keys(struct ieee80211_sub_if_data *sdata)
 {
         struct ieee80211_key *key;
diff --git a/net/mac80211/key.h b/net/mac80211/key.h
index 2a682d81cee9..8ef56cdfe3d7 100644
--- a/net/mac80211/key.h
+++ b/net/mac80211/key.h
@@ -129,14 +129,13 @@ struct ieee80211_key *ieee80211_key_alloc(u32 cipher, int idx, size_t key_len,
                                           size_t seq_len, const u8 *seq);
 /*
  * Insert a key into data structures (sdata, sta if necessary)
- * to make it used, free old key.
+ * to make it used, free old key. On failure, also free the new key.
  */
-int __must_check ieee80211_key_link(struct ieee80211_key *key,
-                                    struct ieee80211_sub_if_data *sdata,
-                                    struct sta_info *sta);
+int ieee80211_key_link(struct ieee80211_key *key,
+                       struct ieee80211_sub_if_data *sdata,
+                       struct sta_info *sta);
 void __ieee80211_key_free(struct ieee80211_key *key, bool delay_tailroom);
-void ieee80211_key_free(struct ieee80211_local *local,
-                        struct ieee80211_key *key);
+void ieee80211_key_free_unused(struct ieee80211_key *key);
 void ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata, int idx,
                                bool uni, bool multi);
 void ieee80211_set_default_mgmt_key(struct ieee80211_sub_if_data *sdata,