[PATCH] can: can327: fix potential skb leak when netdev is down

[Ziyang Xuan]

In can327_feed_frame_to_netdev(), it did not free the skb when netdev
is down, and all callers of can327_feed_frame_to_netdev() did not free
allocated skb too. That would trigger skb leak.

Fix it by adding kfree_skb() in can327_feed_frame_to_netdev() when netdev
is down. Not tested, just compiled.

Fixes: 43da2f07622f ("can: can327: CAN/ldisc driver for ELM327 based OBD-II adapters")
Signed-off-by: Ziyang Xuan <william.xuanziyang@xxxxxxxxxx>
---
 drivers/net/can/can327.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/can/can327.c b/drivers/net/can/can327.c
index 0aa1af31d0fe..17bca63f3dd3 100644
--- a/drivers/net/can/can327.c
+++ b/drivers/net/can/can327.c
@@ -263,8 +263,10 @@ static void can327_feed_frame_to_netdev(struct can327 *elm, struct sk_buff *skb)
 {
 	lockdep_assert_held(&elm->lock);
 
-	if (!netif_running(elm->dev))
+	if (!netif_running(elm->dev)) {
+		kfree_skb(skb);
 		return;
+	}
 
 	/* Queue for NAPI pickup.
 	 * rx-offload will update stats and LEDs for us.
-- 
2.25.1