From: Oliver Hartkopp Date: Wed, 25 Jan 2023 05:54:07 +0000 (+0100) Subject: can: gw: give feedback on missing CGW_FLAGS_CAN_IIF_TX_OK flag X-Git-Tag: v6.6.17~5509^2~124^2~6 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=2a30b2bd01c23a7eeace3a3f82c2817227099805;p=platform%2Fkernel%2Flinux-rpi.git can: gw: give feedback on missing CGW_FLAGS_CAN_IIF_TX_OK flag To send CAN traffic back to the incoming interface a special flag has to be set. When creating a routing job for identical interfaces without this flag the rule is created but has no effect. This patch adds an error return value in the case that the CAN interfaces are identical but the CGW_FLAGS_CAN_IIF_TX_OK flag was not set. Reported-by: Jannik Hartung Signed-off-by: Oliver Hartkopp Link: https://lore.kernel.org/all/20230125055407.2053-1-socketcan@hartkopp.net Signed-off-by: Marc Kleine-Budde --- diff --git a/net/can/gw.c b/net/can/gw.c index 23a3d89c..3752882 100644 --- a/net/can/gw.c +++ b/net/can/gw.c @@ -1139,6 +1139,13 @@ static int cgw_create_job(struct sk_buff *skb, struct nlmsghdr *nlh, if (gwj->dst.dev->type != ARPHRD_CAN) goto out; + /* is sending the skb back to the incoming interface intended? */ + if (gwj->src.dev == gwj->dst.dev && + !(gwj->flags & CGW_FLAGS_CAN_IIF_TX_OK)) { + err = -EINVAL; + goto out; + } + ASSERT_RTNL(); err = cgw_register_filter(net, gwj);