diff mbox series

[5/6] media: dib0700: fix rc endpoint lookup

Message ID 20200103163513.1229-6-johan@kernel.org (mailing list archive)
State Accepted, archived
Delegated to: Sean Young
Headers
Series media: fix USB descriptor issues |

Commit Message

Johan Hovold Jan. 3, 2020, 4:35 p.m. UTC 
  Make sure to use the current alternate setting when verifying the
interface descriptors to avoid submitting an URB to an invalid endpoint.

Failing to do so could cause the driver to misbehave or trigger a WARN()
in usb_submit_urb() that kernels with panic_on_warn set would choke on.

Fixes: c4018fa2e4c0 ("[media] dib0700: fix RC support on Hauppauge Nova-TD")
Cc: stable <stable@vger.kernel.org>     # 3.16
Signed-off-by: Johan Hovold <johan@kernel.org>
---
 drivers/media/usb/dvb-usb/dib0700_core.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/drivers/media/usb/dvb-usb/dib0700_core.c b/drivers/media/usb/dvb-usb/dib0700_core.c
index e53c58ab6488..ef62dd6c5ae4 100644
--- a/drivers/media/usb/dvb-usb/dib0700_core.c
+++ b/drivers/media/usb/dvb-usb/dib0700_core.c
@@ -818,7 +818,7 @@  int dib0700_rc_setup(struct dvb_usb_device *d, struct usb_interface *intf)
 
 	/* Starting in firmware 1.20, the RC info is provided on a bulk pipe */
 
-	if (intf->altsetting[0].desc.bNumEndpoints < rc_ep + 1)
+	if (intf->cur_altsetting->desc.bNumEndpoints < rc_ep + 1)
 		return -ENODEV;
 
 	purb = usb_alloc_urb(0, GFP_KERNEL);
@@ -838,7 +838,7 @@  int dib0700_rc_setup(struct dvb_usb_device *d, struct usb_interface *intf)
 	 * Some devices like the Hauppauge NovaTD model 52009 use an interrupt
 	 * endpoint, while others use a bulk one.
 	 */
-	e = &intf->altsetting[0].endpoint[rc_ep].desc;
+	e = &intf->cur_altsetting->endpoint[rc_ep].desc;
 	if (usb_endpoint_dir_in(e)) {
 		if (usb_endpoint_xfer_bulk(e)) {
 			pipe = usb_rcvbulkpipe(d->udev, rc_ep);