ath5k: disable beacon interrupt when interface is down
When we remove the active interface, there's no need to continue
sending beacons; doing so would cause a null pointer deref in
ieee80211_beacon_get(). Disable the interrupt in remove_interface
and add a WARN_ON(!vif) in case there are other instances lurking.
Signed-off-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath5k/base.c b/drivers/net/wireless/ath/ath5k/base.c
index ab2048b..85a00db 100644
--- a/drivers/net/wireless/ath/ath5k/base.c
+++ b/drivers/net/wireless/ath/ath5k/base.c
@@ -2070,6 +2070,13 @@
return ret;
}
+static void ath5k_beacon_disable(struct ath5k_softc *sc)
+{
+ sc->imask &= ~(AR5K_INT_BMISS | AR5K_INT_SWBA);
+ ath5k_hw_set_imr(sc->ah, sc->imask);
+ ath5k_hw_stop_tx_dma(sc->ah, sc->bhalq);
+}
+
/*
* Transmit a beacon frame at SWBA. Dynamic updates to the
* frame contents are done as needed and the slot time is
@@ -2757,6 +2764,7 @@
goto end;
ath5k_hw_set_lladdr(sc->ah, mac);
+ ath5k_beacon_disable(sc);
sc->vif = NULL;
end:
mutex_unlock(&sc->lock);
@@ -3060,7 +3068,14 @@
{
int ret;
struct ath5k_softc *sc = hw->priv;
- struct sk_buff *skb = ieee80211_beacon_get(hw, vif);
+ struct sk_buff *skb;
+
+ if (WARN_ON(!vif)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ skb = ieee80211_beacon_get(hw, vif);
if (!skb) {
ret = -ENOMEM;