[PATCH 243/270] USB: opticon: fix DMA from stack

[Herton Ronaldo Krzesinski]

3.5.7u1 -stable review patch.  If anyone has any objections, please let me know.

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

From: Johan Hovold <jhovold at gmail.com>

commit ea0dbebffe118724cd4df7d9b071ea8ee48d48f0 upstream.

Make sure to allocate the control-message buffer dynamically as some
platforms cannot do DMA from stack.

Note that only the first byte of the old buffer was used.

Signed-off-by: Johan Hovold <jhovold at gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesinski at canonical.com>
---
 drivers/usb/serial/opticon.c |    7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/serial/opticon.c b/drivers/usb/serial/opticon.c
index 02cb1b7..5ba2700 100644
--- a/drivers/usb/serial/opticon.c
+++ b/drivers/usb/serial/opticon.c
@@ -158,7 +158,11 @@ static int send_control_msg(struct usb_serial_port *port, u8 requesttype,
 {
 	struct usb_serial *serial = port->serial;
 	int retval;
-	u8 buffer[2];
+	u8 *buffer;
+
+	buffer = kzalloc(1, GFP_KERNEL);
+	if (!buffer)
+		return -ENOMEM;
 
 	buffer[0] = val;
 	/* Send the message to the vendor control endpoint
@@ -167,6 +171,7 @@ static int send_control_msg(struct usb_serial_port *port, u8 requesttype,
 				requesttype,
 				USB_DIR_OUT|USB_TYPE_VENDOR|USB_RECIP_INTERFACE,
 				0, 0, buffer, 1, 0);
+	kfree(buffer);
 
 	return retval;
 }
-- 
1.7.9.5