[PATCH can-next 10/10] can: gs_usb: gs_usb_get_minimum_rx_length(): enforce data_length of 8 bytes for CAN error frames

[Marc Kleine-Budde]

By definition, CAN error frames have a length of CAN_ERR_DLC (= 8) bytes.
The gs_update_state() function accesses the data from CAN error frames;
therefore, for error frames increase the value of data_length in
gs_usb_get_minimum_rx_length() to CAN_ERR_DLC.

Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
---
 drivers/net/can/usb/gs_usb.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/net/can/usb/gs_usb.c b/drivers/net/can/usb/gs_usb.c
index 3c0464edb5d3..9ec6fed45b81 100644
--- a/drivers/net/can/usb/gs_usb.c
+++ b/drivers/net/can/usb/gs_usb.c
@@ -576,8 +576,12 @@ gs_usb_get_minimum_rx_length(const struct gs_can *dev, const struct gs_host_fram
 			minimum_length = sizeof(hf->header) + data_length;
 	} else {
 		if (hf->echo_id == GS_HOST_FRAME_ECHO_ID_RX &&
-		    !(hf->can_id & cpu_to_le32(CAN_RTR_FLAG)))
-			data_length = can_cc_dlc2len(hf->can_dlc);
+		    !(hf->can_id & cpu_to_le32(CAN_RTR_FLAG))) {
+			if (hf->can_id & cpu_to_le32(CAN_ERR_FLAG))
+				data_length = CAN_ERR_DLC;
+			else
+				data_length = can_cc_dlc2len(hf->can_dlc);
+		}
 
 		if (dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP)
 			/* timestamp follows data field of max size */

-- 
2.53.0