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Diffstat (limited to 'net/can/isotp.c')
-rw-r--r--net/can/isotp.c74
1 files changed, 48 insertions, 26 deletions
diff --git a/net/can/isotp.c b/net/can/isotp.c
index 9bc344851704..5761d4ab839d 100644
--- a/net/can/isotp.c
+++ b/net/can/isotp.c
@@ -119,7 +119,8 @@ enum {
ISOTP_WAIT_FIRST_FC,
ISOTP_WAIT_FC,
ISOTP_WAIT_DATA,
- ISOTP_SENDING
+ ISOTP_SENDING,
+ ISOTP_SHUTDOWN,
};
struct tpcon {
@@ -880,8 +881,8 @@ 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 */
@@ -918,7 +919,6 @@ 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;
@@ -928,23 +928,24 @@ 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;
}
if (!size || size > MAX_MSG_LENGTH) {
@@ -1074,7 +1075,9 @@ 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;
@@ -1082,13 +1085,15 @@ 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;
}
@@ -1120,7 +1125,7 @@ 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);
@@ -1150,10 +1155,12 @@ 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);
@@ -1608,6 +1615,21 @@ 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)
{
@@ -1623,7 +1645,7 @@ 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,