diff options
Diffstat (limited to 'net/mac80211/key.c')
| -rw-r--r-- | net/mac80211/key.c | 44 |
1 files changed, 23 insertions, 21 deletions
diff --git a/net/mac80211/key.c b/net/mac80211/key.c index 84cf9196820..8c02469b717 100644 --- a/net/mac80211/key.c +++ b/net/mac80211/key.c @@ -30,19 +30,20 @@ * keys and per-station keys. Since each station belongs to an interface, * each station key also belongs to that interface. * - * Hardware acceleration is done on a best-effort basis, for each key - * that is eligible the hardware is asked to enable that key but if - * it cannot do that they key is simply kept for software encryption. - * There is currently no way of knowing this except by looking into - * debugfs. + * Hardware acceleration is done on a best-effort basis for algorithms + * that are implemented in software, for each key the hardware is asked + * to enable that key for offloading but if it cannot do that the key is + * simply kept for software encryption (unless it is for an algorithm + * that isn't implemented in software). + * There is currently no way of knowing whether a key is handled in SW + * or HW except by looking into debugfs. * - * All key operations are protected internally. - * - * Within mac80211, key references are, just as STA structure references, - * protected by RCU. Note, however, that some things are unprotected, - * namely the key->sta dereferences within the hardware acceleration - * functions. This means that sta_info_destroy() must remove the key - * which waits for an RCU grace period. + * All key management is internally protected by a mutex. Within all + * other parts of mac80211, key references are, just as STA structure + * references, protected by RCU. Note, however, that some things are + * unprotected, namely the key->sta dereferences within the hardware + * acceleration functions. This means that sta_info_destroy() must + * remove the key which waits for an RCU grace period. */ static const u8 bcast_addr[ETH_ALEN] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF }; @@ -279,13 +280,8 @@ static void __ieee80211_key_replace(struct ieee80211_sub_if_data *sdata, new->conf.keyidx); } - if (old) { - /* - * We'll use an empty list to indicate that the key - * has already been removed. - */ - list_del_init(&old->list); - } + if (old) + list_del(&old->list); } struct ieee80211_key *ieee80211_key_alloc(u32 cipher, int idx, size_t key_len, @@ -379,6 +375,12 @@ static void __ieee80211_key_destroy(struct ieee80211_key *key) if (!key) return; + /* + * Synchronize so the TX path can no longer be using + * this key before we free/remove it. + */ + synchronize_rcu(); + if (key->local) ieee80211_key_disable_hw_accel(key); @@ -420,8 +422,8 @@ int ieee80211_key_link(struct ieee80211_key *key, struct sta_info *ap; /* - * We're getting a sta pointer in, - * so must be under RCU read lock. + * We're getting a sta pointer in, so must be under + * appropriate locking for sta_info_get(). */ /* same here, the AP could be using QoS */ |