3.2.100-rc1 review patch. If anyone has any objections, please let me know.
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From: Marc Kleine-Budde mkl@pengutronix.de
commit 8cb68751c115d176ec851ca56ecfbb411568c9e8 upstream.
If an invalid CAN frame is received, from a driver or from a tun interface, a Kernel warning is generated.
This patch replaces the WARN_ONCE by a simple pr_warn_once, so that a kernel, bootet with panic_on_warn, does not panic. A printk seems to be more appropriate here.
Reported-by: syzbot+4386709c0c1284dca827@syzkaller.appspotmail.com Suggested-by: Dmitry Vyukov dvyukov@google.com Acked-by: Oliver Hartkopp socketcan@hartkopp.net Signed-off-by: Marc Kleine-Budde mkl@pengutronix.de [bwh: Backported to 3.2: - Keep using the 'drop' label, as it has another user - Adjust context] Signed-off-by: Ben Hutchings ben@decadent.org.uk --- --- a/net/can/af_can.c +++ b/net/can/af_can.c @@ -653,13 +653,13 @@ static int can_rcv(struct sk_buff *skb, if (!net_eq(dev_net(dev), &init_net)) goto drop;
- if (WARN_ONCE(dev->type != ARPHRD_CAN || - skb->len != sizeof(struct can_frame) || - cf->can_dlc > 8, - "PF_CAN: dropped non conform skbuf: " - "dev type %d, len %d, can_dlc %d\n", - dev->type, skb->len, cf->can_dlc)) + if (unlikely(dev->type != ARPHRD_CAN || + skb->len != sizeof(struct can_frame) || + cf->can_dlc > 8)) { + pr_warn_once("PF_CAN: dropped non conform CAN skbuf: dev type %d, len %d, can_dlc %d\n", + dev->type, skb->len, cf->can_dlc); goto drop; + }
/* update statistics */ can_stats.rx_frames++;