--- linux-2.4.30.orig/drivers/char/serial.c	2005-01-19 15:09:50.000000000 +0100
+++ linux-2.4.30/drivers/char/serial.c	2005-05-24 17:23:26.000000000 +0200
@@ -1827,13 +1827,18 @@
 
 static void rs_put_char(struct tty_struct *tty, unsigned char ch)
 {
-	struct async_struct *info = (struct async_struct *)tty->driver_data;
+	struct async_struct *info;
 	unsigned long flags;
 
+	if (!tty)
+		return;
+	
+	info =  (struct async_struct *)tty->driver_data;
+	
 	if (serial_paranoia_check(info, tty->device, "rs_put_char"))
 		return;
 
-	if (!tty || !info->xmit.buf)
+	if (!info->xmit.buf)
 		return;
 
 	save_flags(flags); cli();
@@ -1873,13 +1878,18 @@
 		    const unsigned char *buf, int count)
 {
 	int	c, ret = 0;
-	struct async_struct *info = (struct async_struct *)tty->driver_data;
+	struct async_struct *info;
 	unsigned long flags;
 				
+	if (!tty)
+		return 0;
+
+	info = (struct async_struct *)tty->driver_data;
+	
 	if (serial_paranoia_check(info, tty->device, "rs_write"))
 		return 0;
 
-	if (!tty || !info->xmit.buf || !tmp_buf)
+	if (!info->xmit.buf || !tmp_buf)
 		return 0;
 
 	save_flags(flags);