From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:48246 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388522AbeGPIKq (ORCPT ); Mon, 16 Jul 2018 04:10:46 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Johan Hovold Subject: [PATCH 4.4 09/43] USB: serial: mos7840: fix status-register error handling Date: Mon, 16 Jul 2018 09:36:14 +0200 Message-Id: <20180716073512.783580283@linuxfoundation.org> In-Reply-To: <20180716073511.796555857@linuxfoundation.org> References: <20180716073511.796555857@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold 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(+) --- a/drivers/usb/serial/mos7840.c +++ b/drivers/usb/serial/mos7840.c @@ -482,6 +482,9 @@ static void mos7840_control_callback(str } 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;