1 files changed, 27 insertions, 28 deletions

diff --git a/net/can/isotp.c b/net/can/isotp.c
index f02b5d3e4733..ce588b85665a 100644
--- a/net/can/isotp.c
+++ b/net/can/isotp.c
@@ -72,7 +72,7 @@
 #include <net/sock.h>
 #include <net/net_namespace.h>
 
-MODULE_DESCRIPTION("PF_CAN isotp 15765-2:2016 protocol");
+MODULE_DESCRIPTION("PF_CAN ISO 15765-2 transport protocol");
 MODULE_LICENSE("Dual BSD/GPL");
 MODULE_AUTHOR("Oliver Hartkopp <socketcan@hartkopp.net>");
 MODULE_ALIAS("can-proto-6");
@@ -83,10 +83,11 @@ MODULE_ALIAS("can-proto-6");
 			 (CAN_EFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG) : \
 			 (CAN_SFF_MASK | CAN_EFF_FLAG | CAN_RTR_FLAG))
 
-/* ISO 15765-2:2016 supports more than 4095 byte per ISO PDU as the FF_DL can
- * take full 32 bit values (4 Gbyte). We would need some good concept to handle
- * this between user space and kernel space. For now set the static buffer to
- * something about 8 kbyte to be able to test this new functionality.
+/* Since ISO 15765-2:2016 the CAN isotp protocol supports more than 4095
+ * byte per ISO PDU as the FF_DL can take full 32 bit values (4 Gbyte).
+ * We would need some good concept to handle this between user space and
+ * kernel space. For now set the static buffer to something about 8 kbyte
+ * to be able to test this new functionality.
  */
 #define DEFAULT_MAX_PDU_SIZE 8300
 
@@ -277,6 +278,7 @@ static int isotp_send_fc(struct sock *sk, int ae, u8 flowstatus)
 static void isotp_rcv_skb(struct sk_buff *skb, struct sock *sk)
 {
 	struct sockaddr_can *addr = (struct sockaddr_can *)skb->cb;
+	enum skb_drop_reason reason;
 
 	BUILD_BUG_ON(sizeof(skb->cb) < sizeof(struct sockaddr_can));
 
@@ -284,8 +286,8 @@ static void isotp_rcv_skb(struct sk_buff *skb, struct sock *sk)
 	addr->can_family = AF_CAN;
 	addr->can_ifindex = skb->dev->ifindex;
 
-	if (sock_queue_rcv_skb(sk, skb) < 0)
-		kfree_skb(skb);
+	if (sock_queue_rcv_skb_reason(sk, skb, &reason) < 0)
+		sk_skb_reason_drop(sk, skb, reason);
 }
 
 static u8 padlen(u8 datalen)
@@ -381,8 +383,9 @@ static int isotp_rcv_fc(struct isotp_sock *so, struct canfd_frame *cf, int ae)
 		return 1;
 	}
 
-	/* get communication parameters only from the first FC frame */
-	if (so->tx.state == ISOTP_WAIT_FIRST_FC) {
+	/* get static/dynamic communication params from first/every FC frame */
+	if (so->tx.state == ISOTP_WAIT_FIRST_FC ||
+	    so->opt.flags & CAN_ISOTP_DYN_FC_PARMS) {
 		so->txfc.bs = cf->data[ae + 1];
 		so->txfc.stmin = cf->data[ae + 2];
 
@@ -948,21 +951,18 @@ static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
 	if (!so->bound || so->tx.state == ISOTP_SHUTDOWN)
 		return -EADDRNOTAVAIL;
 
-wait_free_buffer:
-	/* we do not support multiple buffers - for now */
-	if (wq_has_sleeper(&so->wait) && (msg->msg_flags & MSG_DONTWAIT))
-		return -EAGAIN;
+	while (cmpxchg(&so->tx.state, ISOTP_IDLE, ISOTP_SENDING) != ISOTP_IDLE) {
+		/* we do not support multiple buffers - for now */
+		if (msg->msg_flags & MSG_DONTWAIT)
+			return -EAGAIN;
 
-	/* wait for complete transmission of current pdu */
-	err = wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE);
-	if (err)
-		goto err_event_drop;
-
-	if (cmpxchg(&so->tx.state, ISOTP_IDLE, ISOTP_SENDING) != ISOTP_IDLE) {
 		if (so->tx.state == ISOTP_SHUTDOWN)
 			return -EADDRNOTAVAIL;
 
-		goto wait_free_buffer;
+		/* wait for complete transmission of current pdu */
+		err = wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE);
+		if (err)
+			goto err_event_drop;
 	}
 
 	/* PDU size > default => try max_pdu_size */
@@ -1240,12 +1240,13 @@ static int isotp_release(struct socket *sock)
 	sock->sk = NULL;
 
 	release_sock(sk);
+	sock_prot_inuse_add(net, sk->sk_prot, -1);
 	sock_put(sk);
 
 	return 0;
 }
 
-static int isotp_bind(struct socket *sock, struct sockaddr *uaddr, int len)
+static int isotp_bind(struct socket *sock, struct sockaddr_unsized *uaddr, int len)
 {
 	struct sockaddr_can *addr = (struct sockaddr_can *)uaddr;
 	struct sock *sk = sock->sk;
@@ -1312,7 +1313,7 @@ static int isotp_bind(struct socket *sock, struct sockaddr *uaddr, int len)
 		err = -ENODEV;
 		goto out;
 	}
-	if (dev->mtu < so->ll.mtu) {
+	if (READ_ONCE(dev->mtu) < so->ll.mtu) {
 		dev_put(dev);
 		err = -EINVAL;
 		goto out;
@@ -1635,12 +1636,10 @@ static int isotp_init(struct sock *sk)
 	so->rx.buflen = ARRAY_SIZE(so->rx.sbuf);
 	so->tx.buflen = ARRAY_SIZE(so->tx.sbuf);
 
-	hrtimer_init(&so->rxtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT);
-	so->rxtimer.function = isotp_rx_timer_handler;
-	hrtimer_init(&so->txtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT);
-	so->txtimer.function = isotp_tx_timer_handler;
-	hrtimer_init(&so->txfrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT);
-	so->txfrtimer.function = isotp_txfr_timer_handler;
+	hrtimer_setup(&so->rxtimer, isotp_rx_timer_handler, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT);
+	hrtimer_setup(&so->txtimer, isotp_tx_timer_handler, CLOCK_MONOTONIC, HRTIMER_MODE_REL_SOFT);
+	hrtimer_setup(&so->txfrtimer, isotp_txfr_timer_handler, CLOCK_MONOTONIC,
+		      HRTIMER_MODE_REL_SOFT);
 
 	init_waitqueue_head(&so->wait);
 	spin_lock_init(&so->rx_lock);