linux-kernel - [PATCH 04/10] TTY: serial, use tty_port_close

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Wed,  9 Nov 2011 21:33:46 +0100
From:	Jiri Slaby <jslaby@...e.cz>
To:	gregkh@...e.de
Cc:	linux-kernel@...r.kernel.org, linux-serial@...r.kernel.org,
	jirislaby@...il.com, Alan Cox <alan@...ux.intel.com>
Subject: [PATCH 04/10] TTY: serial, use tty_port_close_start helper

After the previous patches, the code is almost identical. There are
few differences in the helper code:
1) flush_buffer when flow_stopped
   * when a user doesn't care about the data, delete it anyways
2) ASYNCB_INITIALIZED test before wait_until_sent_from
   * obviously, there is nothing to wait for if the port is dead
3) drain_delay wait
   * we don't set drain_delay

So we can use the helper now. It indeed removes a bunch of duplicated
code.

Signed-off-by: Jiri Slaby <jslaby@...e.cz>
Cc: Greg Kroah-Hartman <gregkh@...e.de>
Cc: Alan Cox <alan@...ux.intel.com>
---
 drivers/tty/serial/serial_core.c |   40 +-------------------------------------
 1 files changed, 1 insertions(+), 39 deletions(-)

diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index 2b1ee7c..fcb5342 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -1267,46 +1267,8 @@ static void uart_close(struct tty_struct *tty, struct file *filp)
 
 	pr_debug("uart_close(%d) called\n", uport->line);
 
-	spin_lock_irqsave(&port->lock, flags);
-
-	if (tty_hung_up_p(filp)) {
-		spin_unlock_irqrestore(&port->lock, flags);
+	if (tty_port_close_start(port, tty, filp) == 0)
 		return;
-	}
-
-	if ((tty->count == 1) && (port->count != 1)) {
-		/*
-		 * Uh, oh.  tty->count is 1, which means that the tty
-		 * structure will be freed.  port->count should always
-		 * be one in these conditions.  If it's greater than
-		 * one, we've got real problems, since it means the
-		 * serial port won't be shutdown.
-		 */
-		printk(KERN_ERR "uart_close: bad serial port count; tty->count is 1, "
-		       "port->count is %d\n", port->count);
-		port->count = 1;
-	}
-	if (--port->count < 0) {
-		printk(KERN_ERR "uart_close: bad serial port count for %s: %d\n",
-		       tty->name, port->count);
-		port->count = 0;
-	}
-	if (port->count) {
-		spin_unlock_irqrestore(&port->lock, flags);
-		return;
-	}
-
-	/*
-	 * Now we wait for the transmit buffer to clear; and we notify
-	 * the line discipline to only process XON/XOFF characters by
-	 * setting tty->closing.
-	 */
-	set_bit(ASYNCB_CLOSING, &port->flags);
-	tty->closing = 1;
-	spin_unlock_irqrestore(&port->lock, flags);
-
-	if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE)
-		tty_wait_until_sent_from_close(tty, port->closing_wait);
 
 	/*
 	 * At this point, we stop accepting input.  To do this, we
-- 
1.7.7


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/