[85/93] USB: pl2303: fix device initialisation at open

Submitted by Luis Henriques on June 18, 2013, 11:43 a.m.

Details

Message ID 1371555821-12820-86-git-send-email-luis.henriques@canonical.com
State New
Headers show

Commit Message

Luis Henriques June 18, 2013, 11:43 a.m.
3.5.7.15 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Johan Hovold <jhovold@gmail.com>

commit 2d8f4447b58bba5f8cb895c07690434c02307eaf upstream.

Do not use uninitialised termios data to determine when to configure the
device at open.

This also prevents stack data from leaking to userspace in the OOM error
path.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ luis: backported to 3.5:
  - adjusted context
  - termios is a pointer, not a struct ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
---
 drivers/usb/serial/pl2303.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

Patch hide | download patch | download mbox

diff --git a/drivers/usb/serial/pl2303.c b/drivers/usb/serial/pl2303.c
index 6fe8d0e..5150a27 100644
--- a/drivers/usb/serial/pl2303.c
+++ b/drivers/usb/serial/pl2303.c
@@ -258,7 +258,7 @@  static void pl2303_set_termios(struct tty_struct *tty,
 	   serial settings even to the same values as before. Thus
 	   we actually need to filter in this specific case */
 
-	if (!tty_termios_hw_change(tty->termios, old_termios))
+	if (old_termios && !tty_termios_hw_change(tty->termios, old_termios))
 		return;
 
 	cflag = tty->termios->c_cflag;
@@ -267,7 +267,8 @@  static void pl2303_set_termios(struct tty_struct *tty,
 	if (!buf) {
 		dev_err(&port->dev, "%s - out of memory.\n", __func__);
 		/* Report back no change occurred */
-		*tty->termios = *old_termios;
+		if (old_termios)
+			*tty->termios = *old_termios;
 		return;
 	}
 
@@ -407,7 +408,7 @@  static void pl2303_set_termios(struct tty_struct *tty,
 	control = priv->line_control;
 	if ((cflag & CBAUD) == B0)
 		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
-	else if ((old_termios->c_cflag & CBAUD) == B0)
+	else if (old_termios && (old_termios->c_cflag & CBAUD) == B0)
 		priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
 	if (control != priv->line_control) {
 		control = priv->line_control;
@@ -466,7 +467,6 @@  static void pl2303_close(struct usb_serial_port *port)
 
 static int pl2303_open(struct tty_struct *tty, struct usb_serial_port *port)
 {
-	struct ktermios tmp_termios;
 	struct usb_serial *serial = port->serial;
 	struct pl2303_private *priv = usb_get_serial_port_data(port);
 	int result;
@@ -482,7 +482,7 @@  static int pl2303_open(struct tty_struct *tty, struct usb_serial_port *port)
 
 	/* Setup termios */
 	if (tty)
-		pl2303_set_termios(tty, port, &tmp_termios);
+		pl2303_set_termios(tty, port, NULL);
 
 	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 	if (result) {