b43: Fixup set_key handling

This fixes the key handling for mac80211's new key->flags.
It also adds TX locking to the set_key handler and adds a comment why this is required.
This doesn't fix any known bugs.

Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 20 insertions, 16 deletions

diff --git a/drivers/net/wireless/b43/main.c b/drivers/net/wireless/b43/main.c
index c788bad10661..dad0781b4b67 100644
--- a/drivers/net/wireless/b43/main.c
+++ b/drivers/net/wireless/b43/main.c
@@ -937,8 +937,7 @@ static int b43_key_write(struct b43_wldev *dev,
                 B43_WARN_ON(dev->key[i].keyconf == keyconf);
         }
         if (index < 0) {
-                /* Either pairwise key or address is 00:00:00:00:00:00
-                 * for transmit-only keys. Search the index. */
+                /* Pairwise key. Get an empty slot for the key. */
                 if (b43_new_kidx_api(dev))
                         sta_keys_start = 4;
                 else
@@ -951,7 +950,7 @@ static int b43_key_write(struct b43_wldev *dev,
                         }
                 }
                 if (index < 0) {
-                        b43err(dev->wl, "Out of hardware key memory\n");
+                        b43warn(dev->wl, "Out of hardware key memory\n");
                         return -ENOSPC;
                 }
         } else
@@ -3525,7 +3524,6 @@ static int b43_op_set_key(struct ieee80211_hw *hw, enum set_key_cmd cmd,
 {
         struct b43_wl *wl = hw_to_b43_wl(hw);
         struct b43_wldev *dev;
-        unsigned long flags;
         u8 algorithm;
         u8 index;
         int err;
@@ -3534,7 +3532,15 @@ static int b43_op_set_key(struct ieee80211_hw *hw, enum set_key_cmd cmd,
                 return -ENOSPC; /* User disabled HW-crypto */
 
         mutex_lock(&wl->mutex);
-        spin_lock_irqsave(&wl->irq_lock, flags);
+        spin_lock_irq(&wl->irq_lock);
+        write_lock(&wl->tx_lock);
+        /* Why do we need all this locking here?
+         * mutex     -> Every config operation must take it.
+         * irq_lock  -> We modify the dev->key array, which is accessed
+         *              in the IRQ handlers.
+         * tx_lock   -> We modify the dev->key array, which is accessed
+         *              in the TX handler.
+         */
 
         dev = wl->current_dev;
         err = -ENODEV;
@@ -3551,7 +3557,7 @@ static int b43_op_set_key(struct ieee80211_hw *hw, enum set_key_cmd cmd,
         err = -EINVAL;
         switch (key->alg) {
         case ALG_WEP:
-                if (key->keylen == 5)
+                if (key->keylen == LEN_WEP40)
                         algorithm = B43_SEC_ALGO_WEP40;
                 else
                         algorithm = B43_SEC_ALGO_WEP104;
@@ -3578,17 +3584,14 @@ static int b43_op_set_key(struct ieee80211_hw *hw, enum set_key_cmd cmd,
                         goto out_unlock;
                 }
 
-                if (is_broadcast_ether_addr(addr)) {
-                        /* addr is FF:FF:FF:FF:FF:FF for default keys */
-                        err = b43_key_write(dev, index, algorithm,
-                                            key->key, key->keylen, NULL, key);
-                } else {
-                        /*
-                         * either pairwise key or address is 00:00:00:00:00:00
-                         * for transmit-only keys
-                         */
+                if (key->flags & IEEE80211_KEY_FLAG_PAIRWISE) {
+                        /* Pairwise key with an assigned MAC address. */
                         err = b43_key_write(dev, -1, algorithm,
                                             key->key, key->keylen, addr, key);
+                } else {
+                        /* Group key */
+                        err = b43_key_write(dev, index, algorithm,
+                                            key->key, key->keylen, NULL, key);
                 }
                 if (err)
                         goto out_unlock;
@@ -3620,7 +3623,8 @@ out_unlock:
                        addr);
                 b43_dump_keymemory(dev);
         }
-        spin_unlock_irqrestore(&wl->irq_lock, flags);
+        write_unlock(&wl->tx_lock);
+        spin_unlock_irq(&wl->irq_lock);
         mutex_unlock(&wl->mutex);
 
         return err;