4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ganapathi Bhat <gbhat@xxxxxxxxxxx> [ Upstream commit b817047ae70c0bd67b677b65d0d69d72cd6e9728 ] Race condition is observed during rmmod of mwifiex_usb: 1. The rmmod thread will call mwifiex_usb_disconnect(), download SHUTDOWN command and do wait_event_interruptible_timeout(), waiting for response. 2. The main thread will handle the response and will do a wake_up_interruptible(), unblocking rmmod thread. 3. On getting unblocked, rmmod thread will make rx_cmd.urb = NULL in mwifiex_usb_free(). 4. The main thread will try to resubmit rx_cmd.urb in mwifiex_usb_submit_rx_urb(), which is NULL. To fix, wait for main thread to complete before calling mwifiex_usb_free(). Signed-off-by: Ganapathi Bhat <gbhat@xxxxxxxxxxx> Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/net/wireless/mwifiex/usb.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/net/wireless/mwifiex/usb.c +++ b/drivers/net/wireless/mwifiex/usb.c @@ -624,6 +624,9 @@ static void mwifiex_usb_disconnect(struc MWIFIEX_FUNC_SHUTDOWN); } + if (adapter->workqueue) + flush_workqueue(adapter->workqueue); + mwifiex_usb_free(card); mwifiex_dbg(adapter, FATAL,
