can: move ifindex to CAN skb extensions

When routing CAN frames over different CAN interfaces the interface index
skb->iif is overwritten with every single hop. To prevent sending a CAN
frame back to its originating (first) incoming CAN interface another
ifindex variable is needed, which was stored in can_skb_priv::ifindex.

Move the can_skb_priv::ifindex content to can_skb_ext::can_iif.

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://patch.msgid.link/20260201-can_skb_ext-v8-3-3635d790fe8b@hartkopp.net
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

diff --git a/drivers/net/can/dev/skb.c b/drivers/net/can/dev/skb.c
index c572745565f6d0ff25729039220614ecb117e2b3..470255fe7367b6ff038e45255abc3ea9eed88704 100644 (file)
--- a/drivers/net/can/dev/skb.c
+++ b/drivers/net/can/dev/skb.c
@@ -223,7 +223,7 @@ struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf)
 
        skb->protocol = htons(ETH_P_CAN);
        init_can_skb_reserve(skb);
-       can_skb_prv(skb)->ifindex = dev->ifindex;
+       csx->can_iif = dev->ifindex;
 
        *cf = skb_put_zero(skb, sizeof(struct can_frame));
 
@@ -255,7 +255,7 @@ struct sk_buff *alloc_canfd_skb(struct net_device *dev,
 
        skb->protocol = htons(ETH_P_CANFD);
        init_can_skb_reserve(skb);
-       can_skb_prv(skb)->ifindex = dev->ifindex;
+       csx->can_iif = dev->ifindex;
 
        *cfd = skb_put_zero(skb, sizeof(struct canfd_frame));
 
@@ -294,7 +294,7 @@ struct sk_buff *alloc_canxl_skb(struct net_device *dev,
 
        skb->protocol = htons(ETH_P_CANXL);
        init_can_skb_reserve(skb);
-       can_skb_prv(skb)->ifindex = dev->ifindex;
+       csx->can_iif = dev->ifindex;
 
        *cxl = skb_put_zero(skb, CANXL_HDR_SIZE + data_len);
 
@@ -344,8 +344,7 @@ static bool can_skb_headroom_valid(struct net_device *dev, struct sk_buff *skb)
                                return false;
                }
 
-               can_skb_prv(skb)->ifindex = dev->ifindex;
-
+               csx->can_iif = dev->ifindex;
                skb->ip_summed = CHECKSUM_UNNECESSARY;
 
                /* perform proper loopback on capable devices */

diff --git a/net/can/bcm.c b/net/can/bcm.c
index 38452069dea883a35b86ba2d085d5c37a11a909d..f102d17e86190b7a46f806870991136c0b416b0d 100644 (file)
--- a/net/can/bcm.c
+++ b/net/can/bcm.c
@@ -323,7 +323,7 @@ static void bcm_can_tx(struct bcm_op *op)
        }
 
        can_skb_reserve(skb);
-       can_skb_prv(skb)->ifindex = dev->ifindex;
+       csx->can_iif = dev->ifindex;
 
        skb_put_data(skb, cf, op->cfsiz);
 
@@ -1357,7 +1357,7 @@ static int bcm_tx_send(struct msghdr *msg, int ifindex, struct sock *sk,
                return -ENODEV;
        }
 
-       can_skb_prv(skb)->ifindex = dev->ifindex;
+       csx->can_iif = dev->ifindex;
        skb->dev = dev;
        can_skb_set_owner(skb, sk);
        err = can_send(skb, 1); /* send with loopback */

diff --git a/net/can/gw.c b/net/can/gw.c
index 191afe3b673cf7d1d712c0ae761fd31d5bd529c4..816154a978c1bad0f50c21484ba96a79afddc4e2 100644 (file)
--- a/net/can/gw.c
+++ b/net/can/gw.c
@@ -505,7 +505,7 @@ static void can_can_gw_rcv(struct sk_buff *skb, void *data)
 
        /* is sending the skb back to the incoming interface not allowed? */
        if (!(gwj->flags & CGW_FLAGS_CAN_IIF_TX_OK) &&
-           can_skb_prv(skb)->ifindex == gwj->dst.dev->ifindex)
+           csx->can_iif == gwj->dst.dev->ifindex)
                return;
 
        /* clone the given skb, which has not been done in can_rcv()

diff --git a/net/can/isotp.c b/net/can/isotp.c
index 1346dac0f382f1037ce0727597624e35764b11a5..164c4fbf3e2310a64631eb296e3b68b9c7d70ac3 100644 (file)
--- a/net/can/isotp.c
+++ b/net/can/isotp.c
@@ -237,7 +237,7 @@ static int isotp_send_fc(struct sock *sk, int ae, u8 flowstatus)
        }
 
        can_skb_reserve(nskb);
-       can_skb_prv(nskb)->ifindex = dev->ifindex;
+       csx->can_iif = dev->ifindex;
 
        nskb->dev = dev;
        can_skb_set_owner(nskb, sk);
@@ -794,7 +794,7 @@ static void isotp_send_cframe(struct isotp_sock *so)
        }
 
        can_skb_reserve(skb);
-       can_skb_prv(skb)->ifindex = dev->ifindex;
+       csx->can_iif = dev->ifindex;
 
        cf = (struct canfd_frame *)skb->data;
        skb_put_zero(skb, so->ll.mtu);
@@ -1031,7 +1031,7 @@ static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
        }
 
        can_skb_reserve(skb);
-       can_skb_prv(skb)->ifindex = dev->ifindex;
+       csx->can_iif = dev->ifindex;
 
        so->tx.len = size;
        so->tx.idx = 0;

diff --git a/net/can/j1939/socket.c b/net/can/j1939/socket.c
index b7fbc6512f16b2999d7a1344d3ea00488b0a0d70..cc698a6dc3635d8f7c9682040271295eec196912 100644 (file)
--- a/net/can/j1939/socket.c
+++ b/net/can/j1939/socket.c
@@ -905,7 +905,7 @@ static struct sk_buff *j1939_sk_alloc_skb(struct net_device *ndev,
        }
 
        can_skb_reserve(skb);
-       can_skb_prv(skb)->ifindex = ndev->ifindex;
+       csx->can_iif = ndev->ifindex;
        skb_reserve(skb, offsetof(struct can_frame, data));
 
        ret = memcpy_from_msg(skb_put(skb, size), msg, size);

diff --git a/net/can/j1939/transport.c b/net/can/j1939/transport.c
index 03fea5bf0f73552f54930a78c006cebcc7e751eb..3456ef481799a2a25ec282629d0d1fa6a1d0686e 100644 (file)
--- a/net/can/j1939/transport.c
+++ b/net/can/j1939/transport.c
@@ -608,7 +608,7 @@ 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;
+       csx->can_iif = priv->ndev->ifindex;
        /* reserve CAN header */
        skb_reserve(skb, offsetof(struct can_frame, data));
 
@@ -1560,7 +1560,7 @@ j1939_session *j1939_session_fresh_new(struct j1939_priv *priv,
 
        skb->dev = priv->ndev;
        can_skb_reserve(skb);
-       can_skb_prv(skb)->ifindex = priv->ndev->ifindex;
+       csx->can_iif = priv->ndev->ifindex;
        skcb = j1939_skb_to_cb(skb);
        memcpy(skcb, rel_skcb, sizeof(*skcb));
 

diff --git a/net/can/raw.c b/net/can/raw.c
index c63af48495b79d6cb48f1553bd5c4c7127fc3479..022154b0f6cc610cdc35af1b18c0fa8777775ee3 100644 (file)
--- a/net/can/raw.c
+++ b/net/can/raw.c
@@ -966,7 +966,7 @@ static int raw_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
        }
 
        can_skb_reserve(skb);
-       can_skb_prv(skb)->ifindex = dev->ifindex;
+       csx->can_iif = dev->ifindex;
 
        /* fill the skb before testing for valid CAN frames */
        err = memcpy_from_msg(skb_put(skb, size), msg, size);