The lbs_free_adapter() function uses timer_delete() (non-synchronous) for both command_timer and tx_lockup_timer before the structure is freed. This is incorrect because timer_delete() does not wait for any running timer callback to complete. If a timer callback is executing when lbs_free_adapter() is called, the callback will access freed memory since lbs_cfg_free() frees the containing structure immediately after lbs_free_adapter() returns. Both timer callbacks (lbs_cmd_timeout_handler and lbs_tx_lockup_handler) access priv->driver_lock, priv->cur_cmd, priv->dev, and other fields, which would all be use-after-free violations. Use timer_delete_sync() instead to ensure any running timer callback has completed before returning. This bug was introduced in commit 8f641d93c38a ("libertas: detect TX lockups and reset hardware") where del_timer() was used instead of del_timer_sync() in the cleanup path. The command_timer has had the same issue since the driver was first written. Fixes: 8f641d93c38a ("libertas: detect TX lockups and reset hardware") Fixes: 954ee164f4f4 ("[PATCH] libertas: reorganize and simplify init sequence") Cc: stable@vger.kernel.org Signed-off-by: Daniel Hodges --- drivers/net/wireless/marvell/libertas/main.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/marvell/libertas/main.c b/drivers/net/wireless/marvell/libertas/main.c index d44e02c6fe38..dd97f1b61f4d 100644 --- a/drivers/net/wireless/marvell/libertas/main.c +++ b/drivers/net/wireless/marvell/libertas/main.c @@ -799,8 +799,8 @@ static void lbs_free_adapter(struct lbs_private *priv) { lbs_free_cmd_buffer(priv); kfifo_free(&priv->event_fifo); - timer_delete(&priv->command_timer); - timer_delete(&priv->tx_lockup_timer); + timer_delete_sync(&priv->command_timer); + timer_delete_sync(&priv->tx_lockup_timer); } static const struct net_device_ops lbs_netdev_ops = { -- 2.52.0