[Patch net] can: initialize skbcnt in j1939_tp_tx_dat_new()

[Cong Wang]

This fixes an uninit-value warning:
BUG: KMSAN: uninit-value in can_receive+0x26b/0x630 net/can/af_can.c:650

Reported-and-tested-by: syzbot+3f3837e61a48d32b4...@syzkaller.appspotmail.com
Fixes: 9d71dd0c7009 ("can: add support of SAE J1939 protocol")
Cc: Robin van der Gracht <ro...@protonic.nl>
Cc: Oleksij Rempel <li...@rempel-privat.de>
Cc: Pengutronix Kernel Team <ker...@pengutronix.de>
Cc: Oliver Hartkopp <socket...@hartkopp.net>
Cc: Marc Kleine-Budde <m...@pengutronix.de>
Signed-off-by: Cong Wang <xiyou.wangc...@gmail.com>
---
 net/can/j1939/transport.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/can/j1939/transport.c b/net/can/j1939/transport.c
index 0cec4152f979..88cf1062e1e9 100644
--- a/net/can/j1939/transport.c
+++ b/net/can/j1939/transport.c
@@ -580,6 +580,7 @@ sk_buff *j1939_tp_tx_dat_new(struct j1939_priv *priv,
        skb->dev = priv->ndev;
        can_skb_reserve(skb);
        can_skb_prv(skb)->ifindex = priv->ndev->ifindex;
+       can_skb_prv(skb)->skbcnt = 0;
        /* reserve CAN header */
        skb_reserve(skb, offsetof(struct can_frame, data));
 
-- 
2.28.0