From: Jiri Slaby <jslaby@xxxxxxx> Make sure that we check the return value of tty_port_tty_get. Sometimes it may return NULL and we later dereference that. There are several places to check. For easier handling, tty_port_tty_get is moved directly to the palce where needed in keyspan_pda_rx_interrupt. Signed-off-by: Jiri Slaby <jslaby@xxxxxxx> Cc: Alan Cox <alan@xxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx> --- drivers/usb/serial/keyspan_pda.c | 15 ++++++++------- 1 files changed, 8 insertions(+), 7 deletions(-) diff --git a/drivers/usb/serial/keyspan_pda.c b/drivers/usb/serial/keyspan_pda.c index 554a869..7b690f3 100644 --- a/drivers/usb/serial/keyspan_pda.c +++ b/drivers/usb/serial/keyspan_pda.c @@ -173,7 +173,8 @@ static void keyspan_pda_wakeup_write(struct work_struct *work) container_of(work, struct keyspan_pda_private, wakeup_work); struct usb_serial_port *port = priv->port; struct tty_struct *tty = tty_port_tty_get(&port->port); - tty_wakeup(tty); + if (tty) + tty_wakeup(tty); tty_kref_put(tty); } @@ -206,7 +207,7 @@ static void keyspan_pda_request_unthrottle(struct work_struct *work) static void keyspan_pda_rx_interrupt(struct urb *urb) { struct usb_serial_port *port = urb->context; - struct tty_struct *tty = tty_port_tty_get(&port->port); + struct tty_struct *tty; unsigned char *data = urb->transfer_buffer; int retval; int status = urb->status; @@ -223,7 +224,7 @@ static void keyspan_pda_rx_interrupt(struct urb *urb) /* this urb is terminated, clean up */ dbg("%s - urb shutting down with status: %d", __func__, status); - goto out; + return; default: dbg("%s - nonzero urb status received: %d", __func__, status); @@ -233,12 +234,14 @@ static void keyspan_pda_rx_interrupt(struct urb *urb) /* see if the message is data or a status interrupt */ switch (data[0]) { case 0: - /* rest of message is rx data */ - if (urb->actual_length) { + tty = tty_port_tty_get(&port->port); + /* rest of message is rx data */ + if (tty && urb->actual_length) { tty_insert_flip_string(tty, data + 1, urb->actual_length - 1); tty_flip_buffer_push(tty); } + tty_kref_put(tty); break; case 1: /* status interrupt */ @@ -265,8 +268,6 @@ exit: dev_err(&port->dev, "%s - usb_submit_urb failed with result %d", __func__, retval); -out: - tty_kref_put(tty); } -- 1.7.4.1 -- 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