package/mac80211/patches/008-mac80211-fix-todo-lock.patch

   1 From: Johannes Berg <johannes@sipsolutions.net>
   2 Subject: mac80211: fix todo lock
   3
   4 The key todo lock can be taken from different locks
   5 that require it to be _bh to avoid lock inversion
   6 due to (soft)irqs.
   7
   8 This should fix the two problems reported by Bob and
   9 Gabor:
  10 http://mid.gmane.org/20090619113049.GB18956@hash.localnet
  11 http://mid.gmane.org/4A3FA376.8020307@openwrt.org
  12
  13 Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
  14 Cc: Bob Copeland <me@bobcopeland.com>
  15 Cc: Gabor Juhos <juhosg@openwrt.org>
  16 ---
  17  net/mac80211/key.c |   28 +++++++++++++++-------------
  18  1 file changed, 15 insertions(+), 13 deletions(-)
  19
  20 --- a/net/mac80211/key.c
  21 +++ b/net/mac80211/key.c
  22 @@ -70,6 +70,8 @@ static DECLARE_WORK(todo_work, key_todo)
  23   *
  24   * @key: key to add to do item for
  25   * @flag: todo flag(s)
  26 + *
  27 + * Must be called with IRQs or softirqs disabled.
  28   */
  29  static void add_todo(struct ieee80211_key *key, u32 flag)
  30  {
  31 @@ -143,9 +145,9 @@ static void ieee80211_key_enable_hw_acce
  32         ret = drv_set_key(key->local, SET_KEY, &sdata->vif, sta, &key->conf);
  33
  34         if (!ret) {
  35 -               spin_lock(&todo_lock);
  36 +               spin_lock_bh(&todo_lock);
  37                 key->flags |= KEY_FLAG_UPLOADED_TO_HARDWARE;
  38 -               spin_unlock(&todo_lock);
  39 +               spin_unlock_bh(&todo_lock);
  40         }
  41
  42         if (ret && ret != -ENOSPC && ret != -EOPNOTSUPP)
  43 @@ -167,12 +169,12 @@ static void ieee80211_key_disable_hw_acc
  44         if (!key || !key->local->ops->set_key)
  45                 return;
  46
  47 -       spin_lock(&todo_lock);
  48 +       spin_lock_bh(&todo_lock);
  49         if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)) {
  50 -               spin_unlock(&todo_lock);
  51 +               spin_unlock_bh(&todo_lock);
  52                 return;
  53         }
  54 -       spin_unlock(&todo_lock);
  55 +       spin_unlock_bh(&todo_lock);
  56
  57         sta = get_sta_for_key(key);
  58         sdata = key->sdata;
  59 @@ -191,9 +193,9 @@ static void ieee80211_key_disable_hw_acc
  60                        wiphy_name(key->local->hw.wiphy),
  61                        key->conf.keyidx, sta ? sta->addr : bcast_addr, ret);
  62
  63 -       spin_lock(&todo_lock);
  64 +       spin_lock_bh(&todo_lock);
  65         key->flags &= ~KEY_FLAG_UPLOADED_TO_HARDWARE;
  66 -       spin_unlock(&todo_lock);
  67 +       spin_unlock_bh(&todo_lock);
  68  }
  69
  70  static void __ieee80211_set_default_key(struct ieee80211_sub_if_data *sdata,
  71 @@ -440,14 +442,14 @@ void ieee80211_key_link(struct ieee80211
  72
  73         __ieee80211_key_replace(sdata, sta, old_key, key);
  74
  75 -       spin_unlock_irqrestore(&sdata->local->key_lock, flags);
  76 -
  77         /* free old key later */
  78         add_todo(old_key, KEY_FLAG_TODO_DELETE);
  79
  80         add_todo(key, KEY_FLAG_TODO_ADD_DEBUGFS);
  81         if (netif_running(sdata->dev))
  82                 add_todo(key, KEY_FLAG_TODO_HWACCEL_ADD);
  83 +
  84 +       spin_unlock_irqrestore(&sdata->local->key_lock, flags);
  85  }
  86
  87  static void __ieee80211_key_free(struct ieee80211_key *key)
  88 @@ -550,7 +552,7 @@ static void __ieee80211_key_todo(void)
  89          */
  90         synchronize_rcu();
  91
  92 -       spin_lock(&todo_lock);
  93 +       spin_lock_bh(&todo_lock);
  94         while (!list_empty(&todo_list)) {
  95                 key = list_first_entry(&todo_list, struct ieee80211_key, todo);
  96                 list_del_init(&key->todo);
  97 @@ -561,7 +563,7 @@ static void __ieee80211_key_todo(void)
  98                                           KEY_FLAG_TODO_HWACCEL_REMOVE |
  99                                           KEY_FLAG_TODO_DELETE);
 100                 key->flags &= ~todoflags;
 101 -               spin_unlock(&todo_lock);
 102 +               spin_unlock_bh(&todo_lock);
 103
 104                 work_done = false;
 105
 106 @@ -594,9 +596,9 @@ static void __ieee80211_key_todo(void)
 107
 108                 WARN_ON(!work_done);
 109
 110 -               spin_lock(&todo_lock);
 111 +               spin_lock_bh(&todo_lock);
 112         }
 113 -       spin_unlock(&todo_lock);
 114 +       spin_unlock_bh(&todo_lock);
 115  }
 116
 117  void ieee80211_key_todo(void)