AF_UNIX: Fix poll blocking problem when reading from a stream socket

poll() call may be blocked by concurrent reading from the same stream
socket.

Signed-off-by: Alexey Moiseytsev <himeraster@gmail.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Alexey Moiseytsev 2011-11-21 13:35:25 +00:00 коммит произвёл David S. Miller
Родитель 83b98fb46f
Коммит 0884d7aa24
1 изменённых файлов: 4 добавлений и 0 удалений

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@ -1957,6 +1957,7 @@ static int unix_stream_recvmsg(struct kiocb *iocb, struct socket *sock,
if ((UNIXCB(skb).pid != siocb->scm->pid) ||
(UNIXCB(skb).cred != siocb->scm->cred)) {
skb_queue_head(&sk->sk_receive_queue, skb);
sk->sk_data_ready(sk, skb->len);
break;
}
} else {
@ -1974,6 +1975,7 @@ static int unix_stream_recvmsg(struct kiocb *iocb, struct socket *sock,
chunk = min_t(unsigned int, skb->len, size);
if (memcpy_toiovec(msg->msg_iov, skb->data, chunk)) {
skb_queue_head(&sk->sk_receive_queue, skb);
sk->sk_data_ready(sk, skb->len);
if (copied == 0)
copied = -EFAULT;
break;
@ -1991,6 +1993,7 @@ static int unix_stream_recvmsg(struct kiocb *iocb, struct socket *sock,
/* put the skb back if we didn't use it up.. */
if (skb->len) {
skb_queue_head(&sk->sk_receive_queue, skb);
sk->sk_data_ready(sk, skb->len);
break;
}
@ -2006,6 +2009,7 @@ static int unix_stream_recvmsg(struct kiocb *iocb, struct socket *sock,
/* put message back and return */
skb_queue_head(&sk->sk_receive_queue, skb);
sk->sk_data_ready(sk, skb->len);
break;
}
} while (size);