From 1c0ee046957648106b415df79038e4e62b144c19 Mon Sep 17 00:00:00 2001 From: Marc Kleine-Budde Date: Sat, 11 Jul 2015 21:16:08 +0200 Subject: [PATCH] can: pcan_usb: don't touch skb after netif_rx() There is no guarantee that the skb is in the same state after calling net_receive_skb() or netif_rx(). It might be freed or reused. Not really harmful as its a read access, except you turn on the proper debugging options which catch a use after free. Cc: Stephane Grosjean Signed-off-by: Marc Kleine-Budde --- drivers/net/can/usb/peak_usb/pcan_usb.c | 7 +++---- drivers/net/can/usb/peak_usb/pcan_usb_pro.c | 4 ++-- 2 files changed, 5 insertions(+), 6 deletions(-) diff --git a/drivers/net/can/usb/peak_usb/pcan_usb.c b/drivers/net/can/usb/peak_usb/pcan_usb.c index 72427f21edff..6b94007ae052 100644 --- a/drivers/net/can/usb/peak_usb/pcan_usb.c +++ b/drivers/net/can/usb/peak_usb/pcan_usb.c @@ -526,9 +526,9 @@ static int pcan_usb_decode_error(struct pcan_usb_msg_context *mc, u8 n, hwts->hwtstamp = timeval_to_ktime(tv); } - netif_rx(skb); mc->netdev->stats.rx_packets++; mc->netdev->stats.rx_bytes += cf->can_dlc; + netif_rx(skb); return 0; } @@ -659,12 +659,11 @@ static int pcan_usb_decode_data(struct pcan_usb_msg_context *mc, u8 status_len) hwts = skb_hwtstamps(skb); hwts->hwtstamp = timeval_to_ktime(tv); - /* push the skb */ - netif_rx(skb); - /* update statistics */ mc->netdev->stats.rx_packets++; mc->netdev->stats.rx_bytes += cf->can_dlc; + /* push the skb */ + netif_rx(skb); return 0; diff --git a/drivers/net/can/usb/peak_usb/pcan_usb_pro.c b/drivers/net/can/usb/peak_usb/pcan_usb_pro.c index dec51717635e..7d61b3279798 100644 --- a/drivers/net/can/usb/peak_usb/pcan_usb_pro.c +++ b/drivers/net/can/usb/peak_usb/pcan_usb_pro.c @@ -553,9 +553,9 @@ static int pcan_usb_pro_handle_canmsg(struct pcan_usb_pro_interface *usb_if, hwts = skb_hwtstamps(skb); hwts->hwtstamp = timeval_to_ktime(tv); - netif_rx(skb); netdev->stats.rx_packets++; netdev->stats.rx_bytes += can_frame->can_dlc; + netif_rx(skb); return 0; } @@ -670,9 +670,9 @@ static int pcan_usb_pro_handle_error(struct pcan_usb_pro_interface *usb_if, peak_usb_get_ts_tv(&usb_if->time_ref, le32_to_cpu(er->ts32), &tv); hwts = skb_hwtstamps(skb); hwts->hwtstamp = timeval_to_ktime(tv); - netif_rx(skb); netdev->stats.rx_packets++; netdev->stats.rx_bytes += can_frame->can_dlc; + netif_rx(skb); return 0; } -- 2.20.1