ACM gadget: fix endianness in notifications

The gadget code exports the bitfield for serial status changes
over the wire in its internal endianness. The fix is to convert
to little endian before sending it over the wire.

Signed-off-by: Oliver Neukum <oneukum@suse.com>
Tested-by: 家瑋 <momo1208@gmail.com>
CC: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/gadget/function/f_acm.c b/drivers/usb/gadget/function/f_acm.c
index a30766c..5e3828d 100644 (file)
--- a/drivers/usb/gadget/function/f_acm.c
+++ b/drivers/usb/gadget/function/f_acm.c
@@ -535,13 +535,15 @@ static int acm_notify_serial_state(struct f_acm *acm)
 {
        struct usb_composite_dev *cdev = acm->port.func.config->cdev;
        int                     status;
+       __le16                  serial_state;
 
        spin_lock(&acm->lock);
        if (acm->notify_req) {
                dev_dbg(&cdev->gadget->dev, "acm ttyGS%d serial state %04x\n",
                        acm->port_num, acm->serial_state);
+               serial_state = cpu_to_le16(acm->serial_state);
                status = acm_cdc_notify(acm, USB_CDC_NOTIFY_SERIAL_STATE,
-                               0, &acm->serial_state, sizeof(acm->serial_state));
+                               0, &serial_state, sizeof(acm->serial_state));
        } else {
                acm->pending = true;
                status = 0;