The TKIP key update callback is called from the RX path, where the driver mutex is already locked. This results in a circular locking bug. Avoid this by removing the lock. Johannes noted that there is a separate bug: The callback still breaks on SDIO hardware, because SDIO hardware access needs to sleep, but we are not allowed to sleep in the callback due to mac80211's RCU locking. Signed-off-by: Michael Buesch <mb@xxxxxxxxx> Tested-by: Larry Finger <Larry.Finger@xxxxxxxxxxxx> Reported-by: kecsa@xxxxxxxxxxxxxxxx Cc: Johannes Berg <johannes@xxxxxxxxxxxxxxxx> Cc: stable <stable@xxxxxxxxxx> --- drivers/net/wireless/b43/main.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) --- wireless-testing.orig/drivers/net/wireless/b43/main.c +++ wireless-testing/drivers/net/wireless/b43/main.c @@ -856,22 +856,19 @@ static void b43_op_update_tkip_key(struc if (B43_WARN_ON(!modparam_hwtkip)) return; - mutex_lock(&wl->mutex); - + /* This is only called from the RX path through mac80211, where + * our mutex is already locked. */ + B43_WARN_ON(!mutex_is_locked(&wl->mutex)); dev = wl->current_dev; - if (!dev || b43_status(dev) < B43_STAT_INITIALIZED) - goto out_unlock; + B43_WARN_ON(!dev || b43_status(dev) < B43_STAT_INITIALIZED); keymac_write(dev, index, NULL); /* First zero out mac to avoid race */ rx_tkip_phase1_write(dev, index, iv32, phase1key); /* only pairwise TKIP keys are supported right now */ if (WARN_ON(!sta)) - goto out_unlock; + return; keymac_write(dev, index, sta->addr); - -out_unlock: - mutex_unlock(&wl->mutex); } static void do_key_write(struct b43_wldev *dev, -- Greetings, Michael. -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
