can: usb: f81604: handle short interrupt urb messages properly

If an interrupt urb is received 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@kernel.org
Assisted-by: gkh_clanker_2000
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://patch.msgid.link/2026022331-opal-evaluator-a928@gregkh
Fixes: 88da17436973 ("can: usb: f81604: add Fintek F81604 support")
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

diff --git a/drivers/net/can/usb/f81604.c b/drivers/net/can/usb/f81604.c
index 76578063ac8239c176817257f43c73d03c9df5b2..c61bd30d1765e61164add72df4c8b0b5590a6b1d 100644 (file)
--- 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;