diff options
| -rw-r--r-- | Documentation/networking/can.txt | 6 | ||||
| -rw-r--r-- | net/can/raw.c | 26 |
2 files changed, 5 insertions, 27 deletions
diff --git a/Documentation/networking/can.txt b/Documentation/networking/can.txt index f3089d423515..0cbe6ec22d6f 100644 --- a/Documentation/networking/can.txt +++ b/Documentation/networking/can.txt @@ -554,12 +554,6 @@ solution for a couple of reasons: not specified in the struct can_frame and therefore it is only valid in CANFD_MTU sized CAN FD frames. - As long as the payload length is <=8 the received CAN frames from CAN FD - capable CAN devices can be received and read by legacy sockets too. When - user-generated CAN FD frames have a payload length <=8 these can be send - by legacy CAN network interfaces too. Sending CAN FD frames with payload - length > 8 to a legacy CAN network interface returns an -EMSGSIZE error. - Implementation hint for new CAN applications: To build a CAN FD aware application use struct canfd_frame as basic CAN diff --git a/net/can/raw.c b/net/can/raw.c index 8be757cca2ec..081e81fd017f 100644 --- a/net/can/raw.c +++ b/net/can/raw.c @@ -121,13 +121,9 @@ static void raw_rcv(struct sk_buff *oskb, void *data) if (!ro->recv_own_msgs && oskb->sk == sk) return; - /* do not pass frames with DLC > 8 to a legacy socket */ - if (!ro->fd_frames) { - struct canfd_frame *cfd = (struct canfd_frame *)oskb->data; - - if (unlikely(cfd->len > CAN_MAX_DLEN)) - return; - } + /* do not pass non-CAN2.0 frames to a legacy socket */ + if (!ro->fd_frames && oskb->len != CAN_MTU) + return; /* clone the given skb to be able to enqueue it into the rcv queue */ skb = skb_clone(oskb, GFP_ATOMIC); @@ -738,9 +734,7 @@ static int raw_recvmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *msg, size_t size, int flags) { struct sock *sk = sock->sk; - struct raw_sock *ro = raw_sk(sk); struct sk_buff *skb; - int rxmtu; int err = 0; int noblock; @@ -751,20 +745,10 @@ static int raw_recvmsg(struct kiocb *iocb, struct socket *sock, if (!skb) return err; - /* - * when serving a legacy socket the DLC <= 8 is already checked inside - * raw_rcv(). Now check if we need to pass a canfd_frame to a legacy - * socket and cut the possible CANFD_MTU/CAN_MTU length to CAN_MTU - */ - if (!ro->fd_frames) - rxmtu = CAN_MTU; - else - rxmtu = skb->len; - - if (size < rxmtu) + if (size < skb->len) msg->msg_flags |= MSG_TRUNC; else - size = rxmtu; + size = skb->len; err = memcpy_toiovec(msg->msg_iov, skb->data, size); if (err < 0) { |