On Thu, Oct 8, 2020 at 10:34 AM Jakub Kicinski <k...@kernel.org> wrote:
>
> On Wed, 7 Oct 2020 23:18:21 -0700 Cong Wang wrote:
> > 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));
>
> Thanks! Looks like there is another can_skb_reserve(skb) on line 1489,
> is that one fine?
I don't know, I only attempt to address the syzbot report. To me,
it at least does not harm to fix that one too. I am fine either way.
Thanks.
