From: Johan Hovold johan@kernel.org
[ Upstream commit 8353da9fa69722b54cba82b2ec740afd3d438748 ]
Fix NULL-pointer dereference on tty open due to a failure to handle a missing interrupt-in endpoint when probing modem ports:
BUG: kernel NULL pointer dereference, address: 0000000000000006 ... RIP: 0010:tiocmget_submit_urb+0x1c/0xe0 [hso] ... Call Trace: hso_start_serial_device+0xdc/0x140 [hso] hso_serial_open+0x118/0x1b0 [hso] tty_open+0xf1/0x490
Fixes: 542f54823614 ("tty: Modem functions for the HSO driver") Signed-off-by: Johan Hovold johan@kernel.org Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/usb/hso.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-)
--- a/drivers/net/usb/hso.c +++ b/drivers/net/usb/hso.c @@ -2650,14 +2650,18 @@ static struct hso_device *hso_create_bul */ if (serial->tiocmget) { tiocmget = serial->tiocmget; + tiocmget->endp = hso_get_ep(interface, + USB_ENDPOINT_XFER_INT, + USB_DIR_IN); + if (!tiocmget->endp) { + dev_err(&interface->dev, "Failed to find INT IN ep\n"); + goto exit; + } + tiocmget->urb = usb_alloc_urb(0, GFP_KERNEL); if (tiocmget->urb) { mutex_init(&tiocmget->mutex); init_waitqueue_head(&tiocmget->waitq); - tiocmget->endp = hso_get_ep( - interface, - USB_ENDPOINT_XFER_INT, - USB_DIR_IN); } else hso_free_tiomget(serial); }