mac80211: Fix accounting of the tailroom-needed counter

When hw acceleration is enabled, the GENERATE_IV or PUT_IV_SPACE flags
will only require headroom space. Consequently, the tailroom-needed
counter can safely be decremented.

Signed-off-by: Ido Yariv <idox.yariv@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 1cd8444..1fbed0a 100644 (file)
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -1226,7 +1226,8 @@ struct ieee80211_vif *wdev_to_ieee80211_vif(struct wireless_dev *wdev);
  *
  * @IEEE80211_KEY_FLAG_GENERATE_IV: This flag should be set by the
  *     driver to indicate that it requires IV generation for this
- *     particular key.
+ *     particular key. Setting this flag does not necessarily mean that SKBs
+ *     will have sufficient tailroom for ICV or MIC.
  * @IEEE80211_KEY_FLAG_GENERATE_MMIC: This flag should be set by
  *     the driver for a TKIP key if it requires Michael MIC
  *     generation in software.
@@ -1238,7 +1239,9 @@ struct ieee80211_vif *wdev_to_ieee80211_vif(struct wireless_dev *wdev);
  * @IEEE80211_KEY_FLAG_PUT_IV_SPACE: This flag should be set by the driver
  *     if space should be prepared for the IV, but the IV
  *     itself should not be generated. Do not set together with
- *     @IEEE80211_KEY_FLAG_GENERATE_IV on the same key.
+ *     @IEEE80211_KEY_FLAG_GENERATE_IV on the same key. Setting this flag does
+ *     not necessarily mean that SKBs will have sufficient tailroom for ICV or
+ *     MIC.
  * @IEEE80211_KEY_FLAG_RX_MGMT: This key will be used to decrypt received
  *     management frames. The flag can help drivers that have a hardware
  *     crypto implementation that doesn't deal with management frames

diff --git a/net/mac80211/key.c b/net/mac80211/key.c
index d808cff..6429d0e 100644 (file)
--- a/net/mac80211/key.c
+++ b/net/mac80211/key.c
@@ -130,9 +130,7 @@ static int ieee80211_key_enable_hw_accel(struct ieee80211_key *key)
        if (!ret) {
                key->flags |= KEY_FLAG_UPLOADED_TO_HARDWARE;
 
-               if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
-                     (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) ||
-                     (key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)))
+               if (!(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC))
                        sdata->crypto_tx_tailroom_needed_cnt--;
 
                WARN_ON((key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE) &&
@@ -180,9 +178,7 @@ static void ieee80211_key_disable_hw_accel(struct ieee80211_key *key)
        sta = key->sta;
        sdata = key->sdata;
 
-       if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
-             (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) ||
-             (key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)))
+       if (!(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC))
                increment_tailroom_need_count(sdata);
 
        ret = drv_set_key(key->local, DISABLE_KEY, sdata,
@@ -878,9 +874,7 @@ void ieee80211_remove_key(struct ieee80211_key_conf *keyconf)
        if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) {
                key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
 
-               if (!((key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC) ||
-                     (key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV) ||
-                     (key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE)))
+               if (!(key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_MMIC))
                        increment_tailroom_need_count(key->sdata);
        }