From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Johan Hovold Subject: [PATCH 4.9 24/32] USB: serial: ark3116: fix register-accessor error handling Date: Fri, 24 Feb 2017 09:38:08 +0100 Message-Id: <20170224083749.991711049@linuxfoundation.org> In-Reply-To: <20170224083746.364657938@linuxfoundation.org> References: <20170224083746.364657938@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold commit 9fef37d7cf170522fb354d6d0ea6de09b9b16678 upstream. The current implementation failed to detect short transfers, something which could lead to bits of the uninitialised heap transfer buffer leaking to user space. Fixes: 149fc791a452 ("USB: ark3116: Setup some basic infrastructure for new ark3116 driver.") Fixes: f4c1e8d597d1 ("USB: ark3116: Make existing functions 16450-aware and add close and release functions.") Reviewed-by: Greg Kroah-Hartman Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/ark3116.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) --- a/drivers/usb/serial/ark3116.c +++ b/drivers/usb/serial/ark3116.c @@ -99,10 +99,17 @@ static int ark3116_read_reg(struct usb_s usb_rcvctrlpipe(serial->dev, 0), 0xfe, 0xc0, 0, reg, buf, 1, ARK_TIMEOUT); - if (result < 0) + if (result < 1) { + dev_err(&serial->interface->dev, + "failed to read register %u: %d\n", + reg, result); + if (result >= 0) + result = -EIO; + return result; - else - return buf[0]; + } + + return buf[0]; } static inline int calc_divisor(int bps)