From 96a7457a14d9cf98cf58de1e26c03180e0f28141 Mon Sep 17 00:00:00 2001 From: Oliver Hartkopp Date: Mon, 12 Sep 2022 19:07:19 +0200 Subject: can: skb: unify skb CAN frame identification helpers Replace open coded checks for sk_buffs containing Classical CAN and CAN FD frame structures as a preparation for CAN XL support. With the added length check the unintended processing of CAN XL frames having the CANXL_XLF bit set can be suppressed even when the skb->len fits to non CAN XL frames. The CAN_RAW socket needs a rework to use these helpers. Therefore the use of these helpers is postponed to the CAN_RAW CAN XL integration. The J1939 protocol gets a check for Classical CAN frames too. Acked-by: Vincent Mailhol Signed-off-by: Oliver Hartkopp Link: https://lore.kernel.org/all/20220912170725.120748-2-socketcan@hartkopp.net Signed-off-by: Marc Kleine-Budde --- net/can/af_can.c | 50 ++++++++++---------------------------------------- net/can/bcm.c | 9 +++++++-- net/can/gw.c | 4 ++-- net/can/isotp.c | 2 +- net/can/j1939/main.c | 4 ++++ 5 files changed, 24 insertions(+), 45 deletions(-) (limited to 'net/can') diff --git a/net/can/af_can.c b/net/can/af_can.c index 1fb49d51b25d..afa6c2151bc4 100644 --- a/net/can/af_can.c +++ b/net/can/af_can.c @@ -199,27 +199,19 @@ static int can_create(struct net *net, struct socket *sock, int protocol, int can_send(struct sk_buff *skb, int loop) { struct sk_buff *newskb = NULL; - struct canfd_frame *cfd = (struct canfd_frame *)skb->data; struct can_pkg_stats *pkg_stats = dev_net(skb->dev)->can.pkg_stats; int err = -EINVAL; - if (skb->len == CAN_MTU) { + if (can_is_can_skb(skb)) { skb->protocol = htons(ETH_P_CAN); - if (unlikely(cfd->len > CAN_MAX_DLEN)) - goto inval_skb; - } else if (skb->len == CANFD_MTU) { + } else if (can_is_canfd_skb(skb)) { skb->protocol = htons(ETH_P_CANFD); - if (unlikely(cfd->len > CANFD_MAX_DLEN)) - goto inval_skb; } else { goto inval_skb; } - /* Make sure the CAN frame can pass the selected CAN netdevice. - * As structs can_frame and canfd_frame are similar, we can provide - * CAN FD frames to legacy CAN drivers as long as the length is <= 8 - */ - if (unlikely(skb->len > skb->dev->mtu && cfd->len > CAN_MAX_DLEN)) { + /* Make sure the CAN frame can pass the selected CAN netdevice. */ + if (unlikely(skb->len > skb->dev->mtu)) { err = -EMSGSIZE; goto inval_skb; } @@ -678,53 +670,31 @@ static void can_receive(struct sk_buff *skb, struct net_device *dev) static int can_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev) { - struct canfd_frame *cfd = (struct canfd_frame *)skb->data; - - if (unlikely(dev->type != ARPHRD_CAN || skb->len != CAN_MTU)) { + if (unlikely(dev->type != ARPHRD_CAN || (!can_is_can_skb(skb)))) { pr_warn_once("PF_CAN: dropped non conform CAN skbuff: dev type %d, len %d\n", dev->type, skb->len); - goto free_skb; - } - /* This check is made separately since cfd->len would be uninitialized if skb->len = 0. */ - if (unlikely(cfd->len > CAN_MAX_DLEN)) { - pr_warn_once("PF_CAN: dropped non conform CAN skbuff: dev type %d, len %d, datalen %d\n", - dev->type, skb->len, cfd->len); - goto free_skb; + kfree_skb(skb); + return NET_RX_DROP; } can_receive(skb, dev); return NET_RX_SUCCESS; - -free_skb: - kfree_skb(skb); - return NET_RX_DROP; } static int canfd_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev) { - struct canfd_frame *cfd = (struct canfd_frame *)skb->data; - - if (unlikely(dev->type != ARPHRD_CAN || skb->len != CANFD_MTU)) { + if (unlikely(dev->type != ARPHRD_CAN || (!can_is_canfd_skb(skb)))) { pr_warn_once("PF_CAN: dropped non conform CAN FD skbuff: dev type %d, len %d\n", dev->type, skb->len); - goto free_skb; - } - /* This check is made separately since cfd->len would be uninitialized if skb->len = 0. */ - if (unlikely(cfd->len > CANFD_MAX_DLEN)) { - pr_warn_once("PF_CAN: dropped non conform CAN FD skbuff: dev type %d, len %d, datalen %d\n", - dev->type, skb->len, cfd->len); - goto free_skb; + kfree_skb(skb); + return NET_RX_DROP; } can_receive(skb, dev); return NET_RX_SUCCESS; - -free_skb: - kfree_skb(skb); - return NET_RX_DROP; } /* af_can protocol functions */ diff --git a/net/can/bcm.c b/net/can/bcm.c index e60161bec850..e5d179ba6f7d 100644 --- a/net/can/bcm.c +++ b/net/can/bcm.c @@ -648,8 +648,13 @@ static void bcm_rx_handler(struct sk_buff *skb, void *data) return; /* make sure to handle the correct frame type (CAN / CAN FD) */ - if (skb->len != op->cfsiz) - return; + if (op->flags & CAN_FD_FRAME) { + if (!can_is_canfd_skb(skb)) + return; + } else { + if (!can_is_can_skb(skb)) + return; + } /* disable timeout */ hrtimer_cancel(&op->timer); diff --git a/net/can/gw.c b/net/can/gw.c index 1ea4cc527db3..23a3d89cad81 100644 --- a/net/can/gw.c +++ b/net/can/gw.c @@ -463,10 +463,10 @@ static void can_can_gw_rcv(struct sk_buff *skb, void *data) /* process strictly Classic CAN or CAN FD frames */ if (gwj->flags & CGW_FLAGS_CAN_FD) { - if (skb->len != CANFD_MTU) + if (!can_is_canfd_skb(skb)) return; } else { - if (skb->len != CAN_MTU) + if (!can_is_can_skb(skb)) return; } diff --git a/net/can/isotp.c b/net/can/isotp.c index 43a27d19cdac..a9d1357f8489 100644 --- a/net/can/isotp.c +++ b/net/can/isotp.c @@ -669,7 +669,7 @@ static void isotp_rcv(struct sk_buff *skb, void *data) if (cf->len <= CAN_MAX_DLEN) { isotp_rcv_sf(sk, cf, SF_PCI_SZ4 + ae, skb, sf_dl); } else { - if (skb->len == CANFD_MTU) { + if (can_is_canfd_skb(skb)) { /* We have a CAN FD frame and CAN_DL is greater than 8: * Only frames with the SF_DL == 0 ESC value are valid. * diff --git a/net/can/j1939/main.c b/net/can/j1939/main.c index 8452b0fbb78c..144c86b0e3ff 100644 --- a/net/can/j1939/main.c +++ b/net/can/j1939/main.c @@ -42,6 +42,10 @@ static void j1939_can_recv(struct sk_buff *iskb, void *data) struct j1939_sk_buff_cb *skcb, *iskcb; struct can_frame *cf; + /* make sure we only get Classical CAN frames */ + if (!can_is_can_skb(iskb)) + return; + /* create a copy of the skb * j1939 only delivers the real data bytes, * the header goes into sockaddr. -- cgit v1.2.3