[PATCH] : ir249_sock_connect_cli.diff

From: Jean Tourrilhes (jt@bougret.hpl.hp.com)
Date: Tue Mar 05 2002 - 20:51:52 EST


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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