The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From e37d1aeda737a20b1846a91a3da3f8b0f00cf690 Mon Sep 17 00:00:00 2001
From: Johan Hovold johan@kernel.org Date: Fri, 17 Jan 2020 10:50:23 +0100 Subject: [PATCH] USB: serial: io_edgeport: handle unbound ports on URB completion
Check for NULL port data in the shared interrupt and bulk completion callbacks to avoid dereferencing a NULL pointer in case a device sends data for a port device which isn't bound to a driver (e.g. due to a malicious device having unexpected endpoints or after an allocation failure on port probe).
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable stable@vger.kernel.org Reviewed-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Johan Hovold johan@kernel.org
diff --git a/drivers/usb/serial/io_edgeport.c b/drivers/usb/serial/io_edgeport.c index 9690a5f4b9d6..0582d78bdb1d 100644 --- a/drivers/usb/serial/io_edgeport.c +++ b/drivers/usb/serial/io_edgeport.c @@ -716,7 +716,7 @@ static void edge_interrupt_callback(struct urb *urb) if (txCredits) { port = edge_serial->serial->port[portNumber]; edge_port = usb_get_serial_port_data(port); - if (edge_port->open) { + if (edge_port && edge_port->open) { spin_lock_irqsave(&edge_port->ep_lock, flags); edge_port->txCredits += txCredits; @@ -1825,7 +1825,7 @@ static void process_rcvd_data(struct edgeport_serial *edge_serial, port = edge_serial->serial->port[ edge_serial->rxPort]; edge_port = usb_get_serial_port_data(port); - if (edge_port->open) { + if (edge_port && edge_port->open) { dev_dbg(dev, "%s - Sending %d bytes to TTY for port %d\n", __func__, rxLen, edge_serial->rxPort);