[PATCH 1/3] can: usb: f81604: handle short interrupt urb messages properly

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

If an interrupt urb is recieved that is not the correct length, properly
detect it and don't attempt to treat the data as valid.

Cc: "Ji-Ze Hong (Peter Hong)" <peter_hong@fintek.com.tw>
Cc: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: Vincent Mailhol <mailhol@kernel.org>
Cc: stable <stable@kernel.org>
Assisted-by: gkh_clanker_2000
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/net/can/usb/f81604.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/net/can/usb/f81604.c b/drivers/net/can/usb/f81604.c
index 76578063ac82..c61bd30d1765 100644
--- a/drivers/net/can/usb/f81604.c
+++ b/drivers/net/can/usb/f81604.c
@@ -620,6 +620,12 @@ static void f81604_read_int_callback(struct urb *urb)
 		netdev_info(netdev, "%s: Int URB aborted: %pe\n", __func__,
 			    ERR_PTR(urb->status));
 
+	if (urb->actual_length < sizeof(*data)) {
+		netdev_warn(netdev, "%s: short int URB: %u < %zu\n",
+			    __func__, urb->actual_length, sizeof(*data));
+		goto resubmit_urb;
+	}
+
 	switch (urb->status) {
 	case 0: /* success */
 		break;
-- 
2.53.0