Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Conflicts:

drivers/net/ethernet/google/gve/gve.h
  3ce934558097 ("gve: Secure enough bytes in the first TX desc for all TCP pkts")
  75eaae158b1b ("gve: Add XDP DROP and TX support for GQI-QPL format")
https://lore.kernel.org/all/20230406104927.45d176f5@canb.auug.org.au/
https://lore.kernel.org/all/c5872985-1a95-0bc8-9dcc-b6f23b439e9d@tessares.net/

Adjacent changes:

net/can/isotp.c
  051737439eae ("can: isotp: fix race between isotp_sendsmg() and isotp_release()")
  96d1c81e6a04 ("can: isotp: add module parameter for maximum pdu size")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>

2 files changed, 52 insertions, 27 deletions

diff --git a/net/can/isotp.c b/net/can/isotp.c
index f1ea91772ae7..a750259cb79c 100644
--- a/net/can/isotp.c
+++ b/net/can/isotp.c
@@ -130,7 +130,8 @@ enum {
 	ISOTP_WAIT_FIRST_FC,
 	ISOTP_WAIT_FC,
 	ISOTP_WAIT_DATA,
-	ISOTP_SENDING
+	ISOTP_SENDING,
+	ISOTP_SHUTDOWN,
 };
 
 struct tpcon {
@@ -903,8 +904,8 @@ static enum hrtimer_restart isotp_tx_timer_handler(struct hrtimer *hrtimer)
 					     txtimer);
 	struct sock *sk = &so->sk;
 
-	/* don't handle timeouts in IDLE state */
-	if (so->tx.state == ISOTP_IDLE)
+	/* don't handle timeouts in IDLE or SHUTDOWN state */
+	if (so->tx.state == ISOTP_IDLE || so->tx.state == ISOTP_SHUTDOWN)
 		return HRTIMER_NORESTART;
 
 	/* we did not get any flow control or echo frame in time */
@@ -941,7 +942,6 @@ static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
 {
 	struct sock *sk = sock->sk;
 	struct isotp_sock *so = isotp_sk(sk);
-	u32 old_state = so->tx.state;
 	struct sk_buff *skb;
 	struct net_device *dev;
 	struct canfd_frame *cf;
@@ -951,23 +951,24 @@ static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
 	int off;
 	int err;
 
-	if (!so->bound)
+	if (!so->bound || so->tx.state == ISOTP_SHUTDOWN)
 		return -EADDRNOTAVAIL;
 
+wait_free_buffer:
 	/* we do not support multiple buffers - for now */
-	if (cmpxchg(&so->tx.state, ISOTP_IDLE, ISOTP_SENDING) != ISOTP_IDLE ||
-	    wq_has_sleeper(&so->wait)) {
-		if (msg->msg_flags & MSG_DONTWAIT) {
-			err = -EAGAIN;
-			goto err_out;
-		}
+	if (wq_has_sleeper(&so->wait) && (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_out;
+	/* wait for complete transmission of current pdu */
+	err = wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE);
+	if (err)
+		goto err_event_drop;
 
-		so->tx.state = ISOTP_SENDING;
+	if (cmpxchg(&so->tx.state, ISOTP_IDLE, ISOTP_SENDING) != ISOTP_IDLE) {
+		if (so->tx.state == ISOTP_SHUTDOWN)
+			return -EADDRNOTAVAIL;
+
+		goto wait_free_buffer;
 	}
 
 	/* PDU size > default => try max_pdu_size */
@@ -1107,7 +1108,9 @@ static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
 
 	if (wait_tx_done) {
 		/* wait for complete transmission of current pdu */
-		wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE);
+		err = wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE);
+		if (err)
+			goto err_event_drop;
 
 		if (sk->sk_err)
 			return -sk->sk_err;
@@ -1115,13 +1118,15 @@ static int isotp_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
 
 	return size;
 
+err_event_drop:
+	/* got signal: force tx state machine to be idle */
+	so->tx.state = ISOTP_IDLE;
+	hrtimer_cancel(&so->txfrtimer);
+	hrtimer_cancel(&so->txtimer);
 err_out_drop:
 	/* drop this PDU and unlock a potential wait queue */
-	old_state = ISOTP_IDLE;
-err_out:
-	so->tx.state = old_state;
-	if (so->tx.state == ISOTP_IDLE)
-		wake_up_interruptible(&so->wait);
+	so->tx.state = ISOTP_IDLE;
+	wake_up_interruptible(&so->wait);
 
 	return err;
 }
@@ -1153,7 +1158,7 @@ static int isotp_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
 	if (ret < 0)
 		goto out_err;
 
-	sock_recv_timestamp(msg, sk, skb);
+	sock_recv_cmsgs(msg, sk, skb);
 
 	if (msg->msg_name) {
 		__sockaddr_check_size(ISOTP_MIN_NAMELEN);
@@ -1183,10 +1188,12 @@ static int isotp_release(struct socket *sock)
 	net = sock_net(sk);
 
 	/* wait for complete transmission of current pdu */
-	wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE);
+	while (wait_event_interruptible(so->wait, so->tx.state == ISOTP_IDLE) == 0 &&
+	       cmpxchg(&so->tx.state, ISOTP_IDLE, ISOTP_SHUTDOWN) != ISOTP_IDLE)
+		;
 
 	/* force state machines to be idle also when a signal occurred */
-	so->tx.state = ISOTP_IDLE;
+	so->tx.state = ISOTP_SHUTDOWN;
 	so->rx.state = ISOTP_IDLE;
 
 	spin_lock(&isotp_notifier_lock);
@@ -1652,6 +1659,21 @@ static int isotp_init(struct sock *sk)
 	return 0;
 }
 
+static __poll_t isotp_poll(struct file *file, struct socket *sock, poll_table *wait)
+{
+	struct sock *sk = sock->sk;
+	struct isotp_sock *so = isotp_sk(sk);
+
+	__poll_t mask = datagram_poll(file, sock, wait);
+	poll_wait(file, &so->wait, wait);
+
+	/* Check for false positives due to TX state */
+	if ((mask & EPOLLWRNORM) && (so->tx.state != ISOTP_IDLE))
+		mask &= ~(EPOLLOUT | EPOLLWRNORM);
+
+	return mask;
+}
+
 static int isotp_sock_no_ioctlcmd(struct socket *sock, unsigned int cmd,
 				  unsigned long arg)
 {
@@ -1667,7 +1689,7 @@ static const struct proto_ops isotp_ops = {
 	.socketpair = sock_no_socketpair,
 	.accept = sock_no_accept,
 	.getname = isotp_getname,
-	.poll = datagram_poll,
+	.poll = isotp_poll,
 	.ioctl = isotp_sock_no_ioctlcmd,
 	.gettstamp = sock_gettstamp,
 	.listen = sock_no_listen,
diff --git a/net/can/j1939/transport.c b/net/can/j1939/transport.c
index fb92c3609e17..fe3df23a2595 100644
--- a/net/can/j1939/transport.c
+++ b/net/can/j1939/transport.c
@@ -604,7 +604,10 @@ sk_buff *j1939_tp_tx_dat_new(struct j1939_priv *priv,
 	/* reserve CAN header */
 	skb_reserve(skb, offsetof(struct can_frame, data));
 
-	memcpy(skb->cb, re_skcb, sizeof(skb->cb));
+	/* skb->cb must be large enough to hold a j1939_sk_buff_cb structure */
+	BUILD_BUG_ON(sizeof(skb->cb) < sizeof(*re_skcb));
+
+	memcpy(skb->cb, re_skcb, sizeof(*re_skcb));
 	skcb = j1939_skb_to_cb(skb);
 	if (swap_src_dst)
 		j1939_skbcb_swap(skcb);