4.14-stable review patch. If anyone has any objections, please let me know.
------------------
From: Tobias Herzog <t-her...@gmx.de>
commit dae3ddba36f8c337fb59cef07d564da6fc9b7551 upstream.
Resetting the write index of the notification buffer on urb unlink (e.g.
closing a cdc-acm device from userspace) may lead to wrong interpretation
of further received notifications, in case the index is not 0 when urb
unlink happens (i.e. when parts of a notification already have been
transferred). On the device side there is no "reset" of the notification
transimission and thus we would get out of sync with the device.
Signed-off-by: Tobias Herzog <t-her...@gmx.de>
Acked-by: Oliver Neukum <oneu...@suse.com>
Cc: stable <sta...@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
drivers/usb/class/cdc-acm.c | 1 -
1 file changed, 1 deletion(-)
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -367,7 +367,6 @@ static void acm_ctrl_irq(struct urb *urb
case -ENOENT:
case -ESHUTDOWN:
/* this urb is terminated, clean up */
- acm->nb_index = 0;
dev_dbg(&acm->control->dev,
"%s - urb shutting down with status: %d\n",
__func__, status);
