[PATCH] : ir249_sock_connect_cli.diff

Jean Tourrilhes (jt@bougret.hpl.hp.com)
Tue, 5 Mar 2002 17:51:52 -0800


ir249_sock_connect_cli.diff :
---------------------------
o [CRITICA] Fix socket connect to remove dangerous cli()
<Tested on SMP>

diff -u -p linux/net/irda/af_irda.d4.c linux/net/irda/af_irda.c
--- linux/net/irda/af_irda.d4.c Tue Mar 5 16:05:10 2002
+++ linux/net/irda/af_irda.c Tue Mar 5 16:43:15 2002
@@ -1025,28 +1025,26 @@ static int irda_connect(struct socket *s
/* Now the loop */
if (sk->state != TCP_ESTABLISHED && (flags & O_NONBLOCK))
return -EINPROGRESS;
-
- cli(); /* To avoid races on the sleep */
-
- /* A Connect Ack with Choke or timeout or failed routing will go to
- * closed. */
+
+ /* Here, there is a race condition : the state may change between
+ * our test and the sleep, via irda_connect_confirm().
+ * The way to workaround that is to sleep with a timeout, so that
+ * we don't sleep forever and check the state when waking up.
+ * 50ms is plenty good enough, because the LAP is already connected.
+ * Jean II */
while (sk->state == TCP_SYN_SENT) {
- interruptible_sleep_on(sk->sleep);
+ interruptible_sleep_on_timeout(sk->sleep, HZ/20);
if (signal_pending(current)) {
- sti();
return -ERESTARTSYS;
}
}

if (sk->state != TCP_ESTABLISHED) {
- sti();
sock->state = SS_UNCONNECTED;
return sock_error(sk); /* Always set at this point */
}

sock->state = SS_CONNECTED;
-
- sti();

/* At this point, IrLMP has assigned our source address */
self->saddr = irttp_get_saddr(self->tsap);
-
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