From 9d34dbab6ef4cd3494b8127d8883100f67e0e4a9 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Mon, 26 Oct 2020 09:25:48 +0100 Subject: USB: serial: cyberjack: fix write-URB completion race commit 985616f0457d9f555fff417d0da56174f70cc14f upstream. The write-URB busy flag was being cleared before the completion handler was done with the URB, something which could lead to corrupt transfers due to a racing write request if the URB is resubmitted. Fixes: 507ca9bc0476 ("[PATCH] USB: add ability for usb-serial drivers to determine if their write urb is currently being used.") Cc: stable # 2.6.13 Reviewed-by: Greg Kroah-Hartman Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/cyberjack.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/usb/serial/cyberjack.c b/drivers/usb/serial/cyberjack.c index ebd76ab07b72..36dd688b5795 100644 --- a/drivers/usb/serial/cyberjack.c +++ b/drivers/usb/serial/cyberjack.c @@ -357,11 +357,12 @@ static void cyberjack_write_bulk_callback(struct urb *urb) struct device *dev = &port->dev; int status = urb->status; unsigned long flags; + bool resubmitted = false; - set_bit(0, &port->write_urbs_free); if (status) { dev_dbg(dev, "%s - nonzero write bulk status received: %d\n", __func__, status); + set_bit(0, &port->write_urbs_free); return; } @@ -394,6 +395,8 @@ static void cyberjack_write_bulk_callback(struct urb *urb) goto exit; } + resubmitted = true; + dev_dbg(dev, "%s - priv->wrsent=%d\n", __func__, priv->wrsent); dev_dbg(dev, "%s - priv->wrfilled=%d\n", __func__, priv->wrfilled); @@ -410,6 +413,8 @@ static void cyberjack_write_bulk_callback(struct urb *urb) exit: spin_unlock_irqrestore(&priv->lock, flags); + if (!resubmitted) + set_bit(0, &port->write_urbs_free); usb_serial_port_softint(port); } -- cgit v1.2.3