can: add missing initialisations in CAN related skbuffs

When accessing CAN network interfaces with AF_PACKET sockets e.g. by dhclient
this can lead to a skb_under_panic due to missing skb initialisations.

Add the missing initialisations at the CAN skbuff creation times on driver
level (rx path) and in the network layer (tx path).

Reported-by: Austin Schuh <austin@peloton-tech.com>
Reported-by: Daniel Steer <daniel.steer@mclaren.com>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

1 files changed, 3 insertions, 0 deletions

diff --git a/net/can/af_can.c b/net/can/af_can.c
index 66e08040ced7..32d710eaf1fc 100644
--- a/net/can/af_can.c
+++ b/net/can/af_can.c
@@ -259,6 +259,9 @@ int can_send(struct sk_buff *skb, int loop)
                 goto inval_skb;
         }
 
+        skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+        skb_reset_mac_header(skb);
         skb_reset_network_header(skb);
         skb_reset_transport_header(skb);