[PATCH] can: ctucanfd: handle skb allocation failure

[Fedor Pchelkin]

If skb allocation fails, the pointer to struct can_frame is NULL. This
is actually handled everywhere inside ctucan_err_interrupt() except for
the only place.

Add the missed NULL check.

Found by Linux Verification Center (linuxtesting.org) with SVACE static
analysis tool.

Fixes: 2dcb8e8782d8 ("can: ctucanfd: add support for CTU CAN FD open-source IP core - bus independent part.")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Fedor Pchelkin <pchelkin@xxxxxxxxx>
---
 drivers/net/can/ctucanfd/ctucanfd_base.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/net/can/ctucanfd/ctucanfd_base.c b/drivers/net/can/ctucanfd/ctucanfd_base.c
index 64c349fd4600..f65c1a1e05cc 100644
--- a/drivers/net/can/ctucanfd/ctucanfd_base.c
+++ b/drivers/net/can/ctucanfd/ctucanfd_base.c
@@ -867,10 +867,12 @@ static void ctucan_err_interrupt(struct net_device *ndev, u32 isr)
 			}
 			break;
 		case CAN_STATE_ERROR_ACTIVE:
-			cf->can_id |= CAN_ERR_CNT;
-			cf->data[1] = CAN_ERR_CRTL_ACTIVE;
-			cf->data[6] = bec.txerr;
-			cf->data[7] = bec.rxerr;
+			if (skb) {
+				cf->can_id |= CAN_ERR_CNT;
+				cf->data[1] = CAN_ERR_CRTL_ACTIVE;
+				cf->data[6] = bec.txerr;
+				cf->data[7] = bec.rxerr;
+			}
 			break;
 		default:
 			netdev_warn(ndev, "unhandled error state (%d:%s)!\n",
-- 
2.39.5