Make sure to stop any submitted write URBs on close(). This specifically avoids a NULL-pointer dereference or use-after-free in case of a late completion event after driver unbind.
Fixes: 648d4e16567e ("USB: serial: opticon: add write support") Cc: stable stable@vger.kernel.org # 2.6.30: xxx: USB: serial: opticon: add chars_in_buffer() implementation Signed-off-by: Johan Hovold johan@kernel.org ---
v2 - add missing address-of operator that was never commit before generating the patch
drivers/usb/serial/opticon.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)
diff --git a/drivers/usb/serial/opticon.c b/drivers/usb/serial/opticon.c index f7bccf14a71f..0af76800bd78 100644 --- a/drivers/usb/serial/opticon.c +++ b/drivers/usb/serial/opticon.c @@ -42,6 +42,8 @@ struct opticon_private { bool cts; int outstanding_urbs; int outstanding_bytes; + + struct usb_anchor anchor; };
@@ -150,6 +152,15 @@ static int opticon_open(struct tty_struct *tty, struct usb_serial_port *port) return res; }
+static void opticon_close(struct usb_serial_port *port) +{ + struct opticon_private *priv = usb_get_serial_port_data(port); + + usb_kill_anchored_urbs(&priv->anchor); + + usb_serial_generic_close(port); +} + static void opticon_write_control_callback(struct urb *urb) { struct usb_serial_port *port = urb->context; @@ -226,10 +237,13 @@ static int opticon_write(struct tty_struct *tty, struct usb_serial_port *port, (unsigned char *)dr, buffer, count, opticon_write_control_callback, port);
+ usb_anchor_urb(urb, &priv->anchor); + /* send it down the pipe */ ret = usb_submit_urb(urb, GFP_ATOMIC); if (ret) { dev_err(&port->dev, "failed to submit write urb: %d\n", ret); + usb_unanchor_urb(urb); goto error; }
@@ -364,6 +378,7 @@ static int opticon_port_probe(struct usb_serial_port *port) return -ENOMEM;
spin_lock_init(&priv->lock); + init_usb_anchor(&priv->anchor);
usb_set_serial_port_data(port, priv);
@@ -391,6 +406,7 @@ static struct usb_serial_driver opticon_device = { .port_probe = opticon_port_probe, .port_remove = opticon_port_remove, .open = opticon_open, + .close = opticon_close, .write = opticon_write, .write_room = opticon_write_room, .chars_in_buffer = opticon_chars_in_buffer,