[PATCH] usb: gadget: Add the gserial port checking in gs_start_tx()

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



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 <baolin.wang@xxxxxxxxxx>
---
 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 3580f19..66a0910 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;
-- 
1.7.9.5

--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [Linux Media]     [Linux Input]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [Old Linux USB Devel Archive]

  Powered by Linux