2001-02-01 18:50:21

by Alan

Subject: AF_UNIX hangs

Looking at net/core/datagram.c:wait_for_packet the code will return 0
when the socket has been shutdown. That causes skb_recv_datagram to loop
which is in itself obviously incorrect for a shutdown socket (its in EOF
state)

I suspect it should read something like

/* Socket shut down? */
if (sk->shutdown & RCV_SHUTDOWN)
{
current->state = TASK_RUNNING;
remove_wait_queue(sk->sleep, &wait);
*err = 0;
return 1;
}

2001-02-01 19:51:15

by Alexey Kuznetsov

Subject: Re: AF_UNIX hangs

Hello!

> Looking at net/core/datagram.c:wait_for_packet the code will return 0

Yep... Damn, specially split errno and ready values and forgot to use
this. 8) Sorry.

Alexey



--- ../vger3-010130/linux/net/core/datagram.c Thu Dec 28 22:44:08 2000
+++ linux/net/core/datagram.c Thu Feb 1 22:45:47 2001
@@ -73,19 +73,19 @@
/* Socket errors? */
error = sock_error(sk);
if (error)
- goto out;
+ goto out_err;

if (!skb_queue_empty(&sk->receive_queue))
goto ready;

/* Socket shut down? */
if (sk->shutdown & RCV_SHUTDOWN)
- goto out;
+ goto out_noerr;

/* Sequenced packets can come disconnected. If so we report the problem */
error = -ENOTCONN;
if(connection_based(sk) && !(sk->state==TCP_ESTABLISHED || sk->state==TCP_LISTEN))
- goto out;
+ goto out_err;

/* handle signals */
if (signal_pending(current))
@@ -100,11 +100,16 @@

interrupted:
error = sock_intr_errno(*timeo_p);
+out_err:
+ *err = error;
out:
current->state = TASK_RUNNING;
remove_wait_queue(sk->sleep, &wait);
- *err = error;
return error;
+out_noerr:
+ *err = 0;
+ error = 1;
+ goto out;
}

/*

2001-02-02 01:18:26

by David Miller

Subject: Re: AF_UNIX hangs

[email protected] writes:
> Yep... Damn, specially split errno and ready values and forgot to use
> this. 8) Sorry.

Patch applied.

Later,
David S. Miller
[email protected]