From 511a36d2f357724312bb3776d2f6eed3890928b2 Mon Sep 17 00:00:00 2001 From: Baolin Wang Date: Thu, 30 Jun 2016 17:10:23 +0800 Subject: [PATCH] usb: gadget: Add the gserial port checking in gs_start_tx() When usb gadget is set gadget serial function, it will be crash in below situation. It will clean the 'port->port_usb' pointer in gserial_disconnect() function when usb link is inactive, but it will release lock for disabling the endpoints in this function. Druing the lock release period, it maybe complete one request to issue gs_write_complete()--->gs_start_tx() function, but the 'port->port_usb' pointer had been set NULL, thus it will be crash in gs_start_tx() function. This patch adds the 'port->port_usb' pointer checking in gs_start_tx() function to avoid this situation. Signed-off-by: Baolin Wang Signed-off-by: Felipe Balbi --- drivers/usb/gadget/function/u_serial.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/usb/gadget/function/u_serial.c b/drivers/usb/gadget/function/u_serial.c index 6ded634..e0cd1e4 100644 --- a/drivers/usb/gadget/function/u_serial.c +++ b/drivers/usb/gadget/function/u_serial.c @@ -375,10 +375,15 @@ __acquires(&port->port_lock) */ { struct list_head *pool = &port->write_pool; - struct usb_ep *in = port->port_usb->in; + struct usb_ep *in; int status = 0; bool do_tty_wake = false; + if (!port->port_usb) + return status; + + in = port->port_usb->in; + while (!port->write_busy && !list_empty(pool)) { struct usb_request *req; int len; -- 2.7.4