From 82b9cb4d3f062aa80f15a4f2a2f567b93e2d0739 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Wed, 4 Jul 2018 17:02:17 +0200 Subject: [PATCH] USB: serial: mos7840: fix status-register error handling commit 794744abfffef8b1f3c0c8a4896177d6d13d653d upstream. Add missing transfer-length sanity check to the status-register completion handler to avoid leaking bits of uninitialised slab data to user space. Fixes: 3f5429746d91 ("USB: Moschip 7840 USB-Serial Driver") Cc: stable # 2.6.19 Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/mos7840.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/usb/serial/mos7840.c b/drivers/usb/serial/mos7840.c index e8669aae14b3..5e490177cf75 100644 --- a/drivers/usb/serial/mos7840.c +++ b/drivers/usb/serial/mos7840.c @@ -481,6 +481,9 @@ static void mos7840_control_callback(struct urb *urb) } dev_dbg(dev, "%s urb buffer size is %d\n", __func__, urb->actual_length); + if (urb->actual_length < 1) + goto out; + dev_dbg(dev, "%s mos7840_port->MsrLsr is %d port %d\n", __func__, mos7840_port->MsrLsr, mos7840_port->port_num); data = urb->transfer_buffer; -- 2.20.1